Title of Invention	WASHING MACHINE WITH BUBBLE FORMING MEANAS
Abstract	A washing machine is provided which comprises bubble generating means (20) for supplying air bubbles into washing liquid within a washer tub (2, 5), and bubble fining means (6, 2,9) for fining the air bubbles supplied into the washing liquid by the bubble generating means (20). The bubble fining means is, for example, rear vanes (29) provided below a pulsator (6) disposed in the washer tub (2, 5).

Title of Invention

WASHING MACHINE WITH BUBBLE FORMING MEANAS

Abstract

A washing machine is provided which comprises bubble generating means (20) for supplying air bubbles into washing liquid within a washer tub (2, 5), and bubble fining means (6, 2,9) for fining the air bubbles supplied into the washing liquid by the bubble generating means (20). The bubble fining means is, for example, rear vanes (29) provided below a pulsator (6) disposed in the washer tub (2, 5).

Full Text	The present invention relates to a washing machine with bubble forming means and, more particularly, to a -washing machine which has a bubble generator for generating air bubbles in a washer tub during washing and rinsing operations. Description of Related Art Washing machines are conventionally known which utilize not only water currents of washing liquid within a washer tub generated by rotation of a pulsator but also a great amount of air bubbles supplied into the washing liquid for washing and rinsing clothes (see Japanese Unexamined Patent Publication No. 7-47188 (1995), for example). In such a washing machine, when air bubbles come into contact with clothes thereby to crush, ultrasonic waves are generated, and micro-vibration thereof causes dirt to be dislodged from clothes. This offers a higher washing effect than a case where air bubbles are not applied to the clothes. Further, the air bubbles come into gaps between clothes to offer a cushioning effect. Tb.is prevents superfluous friction for suppression of wear of the clothes. In addition, the air bubbles cause the clothes to float in the washing liquid, so that the clothes are less liable to stagnate in the bottom of the washer tub. This prevents the clothes from being damaged by friction which may otherwise be caused between the pulsator and the clothes. However, the washing machines adapted to perform the washing operation by supplying air bubbles has the following drawbacks. 1. If the air bubbles supplied into the washing liguid have a greater size, the air bubbles coming into contact with the clothes do not crush thereby to be accumulated under the clothes. In such an event, the clothes are merely floated up, so that no improvement in the washing effect by the air bubbles is expected. Further, larger air bubbles are hardly distributed throughout the clothes, thereby failing to improve the washing effect. 2. Some washing machines are constructed such that air supplied from an air pump is discharged as air bubbles into a washer/dehydrator tub from bubble outlet holes formed in a pulsator. In this case, a centrifugal force generated by the rotation of the pulsator acts on air bubbles accumulated on the rear side of the pulsator, so that the air bubbles are distributed heavily in a peripheral portion of the pulsator by the centrifugal force. Therefore, the number of air bubbles discharged from bubble outlet holes located in the peripheral portion of the pulsator is greater than the number of air bubbles discharged from bubble outlet holes located in a central portion of the pulsator. This results in a nonuniform air bubble distribution in the washer/dehydrator tub, whereby the air bubbles cannot uniformly be supplied toward clothes. 3. A so-called automatic washing machine includes a washer/dehydrator tub rotatably supported in an outer tub. In such an automatic washing machine, a conventional arrangement for bubble supply to the washer/dehydrator tub includes a bubble outlet located in the lower portion of the outer tub (between an outer bottom portion of the washer/dehydrator tub and an inner bottom portion of the outer tub), and through-holes formed in the bottom of the washer/dehydrator tub and a pulsator. That is, air bubbles from the bubble outlet are supplied into the washer/dehydrator tub through the through-holes . However, some of the air bubbles supplied from the bubble outlet are deflected in unintended directions, failing to pass through the through-holes formed in the washer/dehydrator tub. In such an event, the air bubbles supplied from the bubble outlet flow out of the washer/dehydrator tub along the outer bottom surface thereof (into a space between the washer/dehydrator tub and the outer tub), so that the air bubbles are not supplied into the washer/dehydrator tub. 4. The bubble outlet is located on a side wall of the outer tub at a level lower than the bottom of the washer/dehydrator tub, and connected to an air pump via a feed pipe outside the outer tub. Therefore, when the air pump is off, washing liquid or rinsing water comes into the feed pipe, so that dirt, undissolved detergent and the like dislodged from clothes may be accumulated or deposited within the feed pipe thereby to clog the feed pipe. This is problematic in the generation of air bubbles. 5. The air pump is provided remotely from the outer tub (for example, in a top panel located above the outer tub), and the feed pipe extends from the air pump to the bubble outlet located in the lower portion of the outer tub with opposite ends thereof being respectively connected to an outlet of the air pump and the bubble outlet. Therefore, the feed pipe is liable to be bent due to vibration of the outer tub during the operation of the washing machine. When the feed pipe is bent to the extreme, the feed pipe is flattened so that the air supply from the air pump is reduced or stopped, failing to sufficiently supply air bubbles into the washing liquid. 6. The air pump is provided in the top panel of an outer housing, and the outlet of the air pump is connected to the bubble outlet at the lower portion of the outer tub via the feed pipe. Since the feed pipe extends to the lower portion of the outer tub, the connection of the feed pipe to the lower portion of the outer tub is troublesome after incorporation of the outer tub in the outer housing. Therefore, the production of the washing machine is complicated. SUMMARY OF THE INVENTION It is a first object of the present invention to provide a washing machine which ensures proper supply of air bubbles. It is a second object of the present invention to provide a washing machine which offers improved washing and rinsing effects by utilizing air bubbles. It is a third object of the present invention to provide a washing machine which can easily be produced with an improved air bubble feed line arrangement. It is a fourth object of the present invention to provide a washing machine which is free from disturbance of air bubble supply which may otherwise occur due to vibration of the machine during operation thereof. It is a fifth object of the present invention to provide a washing machine which is free from clogging of. an air bubble feed line. It is a sixth object of the present invention to provide a washing machine which is capable of supplying air bubbles as much as possible into a washer tub through bubble outlet holes formed in a pulsator. Accordingly, there is provided a washing machine with bubble fixing means comprising: bubble generating means for supplying air bubbles into washing liquid within a washer tub; bubble fining means for fining the air bubbles supplied into the washing liquid by the bubble generating means; and a pulsator provided within the washer tub, wherein the air bubbles and water currents generated by the pulsator are utilized in combination for clothes washing and rinsing operations, and wherein the pulsator bubble outlet hole for feeding upward within the washer tub the air bubbles supplied into the washing liquid by the bubble generating means; characterized in that the bubble fining means is a vane provided on an under surface of the pulsator. Since the washing machine includes the bubble fining means for fining the air bubbles supplied into the washing liquid by the bubble generating means, dissolution of a detergent in the washing liquid within the- washer tub is promoted, and clothes washing and rinsing effects are improved by micro-vibration (ultrasonic waves) caused when the fine air bubbles come into contact with clothes to be fined and crushed. The washing machine preferably further comprises a pulsator provided within the washer tub and utilizes, in combination, the air bubbles and water currents generated by the pulsator for clothes washing and rinsing operations. In this case, the bubble fining means is preferably provided in the pulsator. With this arrangement, the air bubbles supplied into the washing liquid by the bubble generating means are fined by the pulsator. Since the pulsator which is rotated during the washing and rinsing operations is utilized for the fining of the air bubbles, there is no need for provision of additional bubble fining means. The bubble fining means may be a rear vane provided on an under surface of the pulsator. With this arrangement, the air bubbles are more effectively fined. In this case, the rear vane may be disposed radially on the under surface of the pulsator. It is further preferred that a plurality of such rear vanes are radially provided. The rear vane preferably has a comb shape or an undulated shape. Thus, the rear vane has a greater effective area to improve the bubble fining effect. The pulsator preferably has a bubble outlet hole for feeding upward the air bubbles supplied into the washing liquid by the bubble generating means within the washer tub. In this case, the pulsator has a plurality of compartments which are provided on the rear side (i.e., under side) thereof and radially separated from each other. The compartments each preferably have the bubble outlet hole formed in the ceiling thereof. With this arrangement, the air bubbles supplied below the pulsator by the bubble generating means such as an air pump are accumulated in the respective compartments separated from each other in the pulsator, so that the air bubbles are prevented from being distributed heavily in a peripheral portion of the pulsator due to a centrifugal force generated by rotation of the pulsator. Therefore, the air bubbles are substantially uniformly discharged from the respective bubble outlet holes of the pulsator, whereby the air bubbles are uniformly distributed throughout the clothes in the washing liquid without heavy distribution of the air bubbles in a particular portion within the washer tub. The washer tub may include a washer/dehydrator tub, and an outer tub enclosing the washer/dehydrator tub and capable of retaining water therein. In this case, it is preferred that the outer tub has a bubble outlet provided on a lower wall portion thereof for introducing the air bubbles supplied by the bubble generating means into the outer tub, and the washer/dehydrator tub has a through-hole formed in a lower wall portion thereof for introducing therein the air bubbles supplied into the washing liquid. In this case, it is preferred that the pulsator is rotatably provided on the bottom of the washer/dehydrator tub, and the washer/dehydrator tub has a portion upwardly recessed in the bottom thereof. Further, it is preferred that the bubble outlet opens adjacent the recessed portion (preferably below the recessed portion), and the through-hole is provided in the recessed portion so that the air bubbles supplied from the bubble outlet can be introduced into the washer/dehydrator tub. With this arrangement, the air bubbles introduced from the bubble outlet are accumulated in the recessed portion and then supplied into the washer/dehydrator tub through the through-hole. This prevents the air bubbles from flowing out of the washer/dehydrator tub not through the through-hole, so that the air bubbles are assuredly supplied into the washer/dehydrator tub. The outer tub may be supported in a vibro-insulating manner by an outer frame, and the bubble generating means may include an air supplying means provided above a main body of the washing machine. An air feed line may further be provided which connects the air supplying means to the bubble outlet. In this case, it is preferred that the air feed line is divided into an upper feed line and a lower feed line, which are connected by a connector provided adjacent a side wall of the outer tub. Thus, the upper feed line of the air feed line can easily be connected to the lower feed line by accessing from an upper opening of the outer frame after the outer tub is incorporated in the outer housing in the production of the washing machine. The outer tub can be incorporated in the outer frame after the lower feed line has been disposed below the outer tub to be connected to a bottom portion of the outer tub. Thus, easier production of the washing machine is ensured because a producer does not have to access the bottom of the outer tub which is less accessible. In this connection, it is preferable that the connector is provided at a higher level than the bottom of the outer tub, and more preferably at a higher level than the bottom of the washer/dehydrator tub. The upper feed line is preferably connected horizontally to the lower feed line by the connector. With this arrangement, even if the outer tub is vibrated, the upper feed line is less susceptible to a force horizontally exerted thereto at the connector in a line withdrawing direction. This prevents a failure in bubble supply and leakage of the washing liquid from the washer/dehydrator tub through the connector, which may otherwise occur due to withdrawal of the upper feed line from the lower feed line. The upper feed line is preferably formed of a flexible material. Thus, the vibration of the outer tub caused during the operation of the washing machine is absorbed by the upper feed line, so that the decrease or cease of air supply from the air supplying means can be prevented which may otherwise occur due to the bending of the air feed line. The lower feed line preferably has an inside diameter greater than the upper feed line. Even if the washing liquid comes into the lower feed line when the air supplying means is off, the lower feed line is less susceptible to clogging with dust, lint, undissolved detergent and the like contained in the washing liquid. The washing machine preferably further includes sealing means provided between the pulsator and the washer tub for preventing the air bubbles supplied into the washing liquid from leaking from other portions than the bubble outlet holes formed in the pulsator. Thus, the air bubbles supplied to the rear side of the pulsator are prevented from leaking into the washer tub from a gap between the pulsator and the washer tub, so that the air bubbles are uniformly discharged from the bubble outlet holes. The sealing means is preferably a non-contact sealing mechanism. For example, it is preferred that the sealing means is comprised of a labyrinth mechanism which includes a groove comprising a plurality of cylindrical walls provided on either one of an outer circumferential portion of the pulsator and a bottom wall portion of the washer tub opposed to the outer circumferential portion of the pulsator, and an annular wall provided on the other in a non-contact engagement with an open portion of the groove with play. The bubble outlet hole provided in the pulsator preferably includes a plurality of bubble outlet holes. In this case, the total open area of bubble outlet holes located in a central portion of the pulsator is preferably smaller than the total open area of bubble outlet holes located in a peripheral portion of the pulsator. Since the speed of water flow progressively increases toward the periphery of the pulsator on the rear side thereof, the supply of air bubbles is correspondingly increases toward the periphery thereof. With the total open area of the bubble outlet holes in the peripheral portion being greater than the total open area of the bubble outlet holes in the central portion, the air bubbles can be supplied as much as possible into the washer tub. Where the outer tub is supported in a vibro-insulating manner by the outer frame and the bubble outlet is connected to the air supplying means through the air feed line, the bubble outlet is preferably provided with a check-valve for preventing the washing liquid from flowing back into the air feed line from the outer tub. Thus, dust, detergent and the like are prevented from coming into the air feed line, thereby preventing the reduction in the supply of the air bubbles which may otherwise occur due to clogging of the air feed line. The bubble fining means is preferably capable of generating fine air bubbles having a diameter of about 0.5mm. If the diameter of the fine air bubbles is too small, the air bubbles pass through fiber gaps of clothes and do not easily crush in contact with the clothes, thereby failing to improve the washing effect. If the diameter of the air bubbles is too large, the air bubbles do not crush in contact with the clothes, but are liable to be accumulated under the clothes thereby to float up the clothes. Therefore, the air bubbles preferably have a diameter of about 0.5mm. With emphasis on the sealing mechanism provided between the pulsator and the washer tub, the present invention is embodied as a washing machine which comprises a washer tub, bubble generating means for supplying air bubbles into washing liquid within the washer tub, a pulsator provided within the washer tub and having a bubble outlet hole for supplying into the washer tub the air bubbles supplied into the washing liquid by the bubble generating means, and sealing means provided between the pulsator and the washer tub for preventing the supplied air bubbles from leaking from other portions than the bubble outlet hole into the washer tub. In this case, the sealing means may, for example, be comprised of a labyrinth mechanism which includes a groove comprising a plurality of cylindrical walls provided on either one of an outer circumferential portion of the pulsator and a bottom wall portion of the washer tub opposed to the outer circumferential portion of the pulsator, and an annular wall provided on the other in a non-contact engagement with an open portion of the groove with play. With emphasis on the effective supply of air bubbles into the washer tub, the present invention is embodied as a washing machine which comprises a washer tub, bubble generating means for supplying air bubbles into washing liquid within the washer tub, and a pulsator provided within the washer tub and having a plurality of bubble outlet holes for supplying into the washer tub the air bubbles supplied into the washing liquid by the bubble generating means, wherein the total open area of bubble outlet holes located in a central portion of the pulsator is smaller than the total open area of bubble outlet holes located in a peripheral portion of the pulsator. With emphasis on the mechanism for the prevention of the air feed line clogging, the present invention is embodied as a washing machine which comprises an outer tub supported within an outer frame in a vibro-insulating manner, a washer/dehydrator tub disposed within the outer frame, air supplying means for supplying air bubbles into washing liquid, a bubble outlet provided on a lower wall portion of the outer tub for supplying the air bubbles into the outer tub, a air feed line connecting the air supplying means to the bubble outlet, and a check-valve provided in the bubble outlet for preventing the washing liquid from flowing back into the air feed line from the outer tub. The foregoing and other objects, features and effects of the present invention will become more apparent from the following description of the preferred embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a side sectional view illustrating the overall construction of a washing machine according to one embodiment of the present invention; Fig. 2 is a partial sectional view of the washing machine; Fig. 3A is a plan view of a pulsator, Fig. 3B is a. sectional view taken along a line A-B in Fig. 3A, and Fig. 3C is a sectional view taken along a line D-F in Fig. 3B; Fig. 4 is a partial sectional view illustrating one exemplary bubble outlet arrangement; Fig. 5 is a partial sectional view illustrating another exemplary bubble outlet arrangement; Fig. 6 is a partial sectional view illustrating a washing machine according to another embodiment of the invention; Fig. 7 is a top view illustrating one exemplary rear vane arrangement; Fig. 8 is a side view illustrating another exemplary rear vane arrangement; and Fig. 9 is a partial sectional view illustrating one exemplary bubble outlet hole arrangement. DESCRIPTION OF THE PREFERRED EMBODIMENTS Fig. 1 is a side sectional view illustrating the overall construction of a washing machine according to a first embodiment of the present invention, and Fig. 2 is a partial sectional view of the washing machine. An outer tub 2 is suspendedly supported by a plurality of suspension rods 3 within an outer housing 1 which constitutes an outer frame of the washing machine. This prevents vibration of the outer tub 2 from being transferred to the outer housing 1. Within the outer tub 2, a washer/dehydrator tub 5 having a multiplicity of perforations 4 formed in a circumferential wall thereof is rotatably supported about a rotation shaft provided on the bottom of the outer tub 2. A pulsator 6 for agitating clothes to be washed is provided on the bottom of the washer/dehydrator tub 5. A torque of a motor 7 provided below the outer tub 2 is transmitted to the washer/dehydrator tub 5 and the pulsator 6 via a motor pulley 8, a V-belt 9, a main pulley 10 and a power switching mechanism 11. The power switching mechanism 11 switches the coupling of a driving shaft in such a manner that the washer/dehydrator tub 5 and the pulsator 6 are rotated in unison during a dehydration operation and, otherwise, only the pulsator 6 is rotated. A water supplying mechanism not shown is provided above the outer housing 1 for supplying water into the washer/dehydrator tub 5. A drainage port 12 is provided in a bottom portion of the outer tub 2, and connected to a drainage hose 15 via a drainage valve 13 and a drainage line 14. The drainage valve 13 is provided with a solenoid not shown. When the solenoid is energized, the drainage valve 13 is opened, and a clutch in the power switching mechanism 11 is operated to couple the washer/dehydrator tub 5 to the pulsator 6. Thus, the power switching mechanism 11 permits only the pulsator 6 to be rotated when the drainage valve 13 is closed, and permits the washer/dehydrator tub 5 and the pulsator 6 to be rotated in unison when the drainage valve 13 is open. An annular balance ring 16 for vibro-insulation is attached to an upper edge of the washer/dehydrator tub 5. A water circulation passage 17 is provided along an inner wall portion of the washer/dehydrator tub 5 as extending vertically from the bottom of the washer/dehydrator tub 5 to just below the balance ring 16. A lint filter 18 for trapping dust such as lint in the washing liquid is detachably attached to an upper opening of the water circulation passage 17. An air pump 20 for bubble generation is incorporated in a top panel 19, and an air outlet 20a of the air pump 20 is connected to one end of a first feed pipe 21. The first feed pipe 21 is wound, with some slack, around one of the suspension rods 3 suspending the outer tub 2 outside the outer tub 2. The other end of the first feed pipe 21 is connected horizontally to a connection pipe 22 provided on a side wall of the outer tub 2. Since the connection of the first feed pipe 21 is provided on the side wall of the outer tub 2, the first feed pipe 21 can be connected to the connection pipe 22 after the outer tub 2 is incorporated in the outer housing 1. Therefore, the productivity of the washing machine is improved. A second feed pipe 23 is connected to a lower end of the connection pipe 22, and extends along a bottom portion of the outer tub 2 to a bubble outlet 24. The second feed pipe 23 is firmly fixed to the outer tub 2 and connected to the bubble outlet 24. Thus, the second feed pipe 23 vibrates along with the outer tub 2 when the outer tub 2 is vibrated, so that the second feed pipe 23 will never be inadvertently bent to close the passage therein. The first feed pipe 21 is an elastic tube such as of a rubber having an inside diameter of about 3.5mm. On the other hand, the second feed pipe 23 is a tube having an inside diameter of about 7.2mm. The first feed pipe 21 having a smaller inside diameter is less liable to be bent than the second feed pipe 23 having a greater inside diameter and, therefore, is advantageous in that the passage inside the pipe 21 is less liable to be flattened to be closed. However, the smaller inside diameter of the first feed pipe 21 presents a drawback that the pipe 21 is susceptible to clogging with dust and the like. Conversely, the second feed pipe 23 having a greater inside diameter is liable to be bent thereby to be closed, but insusceptible to clogging with dust because of its greater inside diameter. That is, an upper portion of the feed line is liable to be vibrated together with the outer tub 2 but is less susceptible to intrusion of the washing liquid. Therefore, the upper portion is constituted by the tube which is less liable to be bent but may be susceptible to clogging with dust. On the other hand, a lower portion of the feed line need not absorb the vibration of the outer tub without the fear of bending due to the vibration of the outer tub but is liable to be clogged with dust. Therefore, the lower portion is constituted by the tube which is insusceptible to clogging with dust but may be liable to be bent. Since the clothes are agitated in the washing liquid within the washer/dehydrator tub 5 with the pulsator 6 being rotated on the bottom of the washer/dehydrator tub 5 during the washing and rinsing operations, the outer tub 2 vibrates vertically and laterally. During the dehydration operation, much greater vibration is generated. When the outer tub 2 is vibrated, a force liable to bend the first feed pipe 21 is exerted thereon, because the lower end of the first feed pipe 21 is connected to the connection pipe 22 fixed to the outer tub 2 and the upper end thereof is connected to the air pump 20 disposed in the top panel 19. However, the first feed pipe 21 which is comprised of the smaller inside diameter tube as described above will never be bent at an acute angle to close the air passage defined therein even if the outer tub 2 is vibrated. Further, the lower end of the first feed pipe 21 is connected horizontally to the connection pipe 22. The horizontal connection between the first feed pipe 21 and the connection pipe 22 is hardly subjected to a force exerted in such a direction as to withdraw the first feed pipe 21 from the connection pipe 22 even if the outer tub 2 is vibrated during the operation of the washing machine. This prevents a failure in air supply and leakage of the washing liquid from the washer/dehydrator tub 5 through the connection pipe 22, which may otherwise occur due to the withdrawal of the first feed pipe 21 from the connection pipe 22. Dust and lint dislodged from the clothes, undissolved detergent and the like may settle on the bottom of the outer tub 2. Where no air is supplied to the feed pipes 21, 23 with the air pump being off (e.g., during the rinsing operation and the dehydration operation), the washing liquid easily comes into the second feed pipe 23 through the bubble outlet 24. If the dust, lint, undissolved detergent and the like in the incoming washing liquid are deposited and accumulated on an interior surface of the second feed pipe 23, the second feed pipe 23 may be clogged therewith, so that the air supply may be reduced or stopped. However, the second feed pipe 23 is comprised of the greater inside diameter tube as described above and therefore, even if the washing liquid comes into the second feed pipe 23, the second feed pipe 23 is less liable to be clogged with the dust, lint and undissolved detergent in the washing liquid. The second feed pipe 23 is comprised of the tube in this embodiment but may, for example, be comprised of a duct which is formed integrally with the bottom portion of the outer tub 2 and has a sectional area large enough to be free from clogging with the dust, lint and the like. According to a modification of the bubble outlet as shown in Fig. 4, the bubble outlet 24 is provided with a check-valve 24a for preventing the washing liquid from flowing back from the outer tub 2 toward the air pump 20 through the feed pipe 23. This arrangement permits the air from the air pump 20 to be supplied into the outer tub 2, but does not permit the washing liquid to flow back into the feed pipe 23. Therefore, the dust, lint, undissolved detergent and the like in the washing liquid are prevented from being deposited within the feed pipe 23. Since the washing liquid is prevented from coming into the feed pipe 23, a freeze problem in winter can be avoided which may otherwise occur due to washing liquid remaining in the feed pipe 23. An upwardly recessed portion 26 having a donut-like shape is formed on the bottom of the washer/dehydrator tub 5 as surrounding a rotation shaft 25 of the washer/dehydrator tub 5. On the bottom of the washer/dehydrator tub 5, the recessed portion 26 is formed with a plurality of through-holes 27 for communication of the washing liquid between the washer/dehydrator tub 5 and the outer tub 2 and for passage of the bubbles of the air from the air pump 20. The through-holes 27 are located above the bubble outlet 24. The bubbles of the air supplied by the air pump 20 through the bubble outlet 24 come into the washer/dehydrator tub 5 through the through-holes 27. Some of the bubbles are once trapped in the recessed portion 26 and then come into the washer/dehydrator tub 5 through the through-holes 27. Figs. 3A to 3C are diagrams illustrating the pulsator 6 in detail, particularly, Fig. 3A is a top plan view of the pulsator 6, Fig. 3B is a sectional view taken along a line A-B in Fig. 3A, and Fig. 3C is a sectional view taken along a line D-F in Fig. 3B. The pulsator 6 includes agitation vanes 28 provided on its upper surface for generating water currents within the washer/dehydrator tub 5, and rear vanes 29 formed radially on its under surface. The rear vanes 29 have the function of pumping up part of the washing liquid present between the washer/dehydrator tub 5 and the outer tub 2. The rear vanes 29 also have the function of fining the air bubbles generated from the bubble outlet 24. The pulsator 6 comprises a generally disk-shaped pulsator body 30 and the plurality of agitation vanes 28 attached to the body 30. The pulsator body 30 is a generally disk-shaped one-piece member formed of a resin material, and includes a boss 31 projecting upward for mounting the pulsator 6 to the rotation shaft. The pulsator body 30 has five agitation vane mounting portions 32 radially formed around the boss 31 at generally equidistant angular intervals on the upper surface thereof, and flat portions 33 between each adjacent pair of agitation vane mounting portions, each of the flat portions 33 being provided with a slightly concaved portion in a generally radially middle portion thereof. The pulsator body 30 further has drainage holes 34 formed in the flat portions 33 thereof for communication between the upper and lower sides of the pulsator body 30, and water ejection holes 35 formed in a peripheral portion thereof. A peripheral rib 36 is provided circumferentially on an under surface of the pulsator body 30 as projecting downward, and the plurality of rear vanes 29 are provided as extending radially (i.e., in pulsator radial directions) from the boss 31 to the peripheral rib 36. The agitation vane mounting portions 32 protrude upward from the flat portions 33 in a generally inverted-U-shape, and the agitation vanes 28 are mounted on top of the agitation vane mounting portions 32. The inside spaces of the agitation vane mounting portions 32 are each divided into three compartments 37a, 37b, 37c, and bubble outlet holes 38 for ejecting air bubbles are formed in ceilings of the respective compartments 37a, 37b, 37c as extending through the agitation vane 28 and the agitation vane mounting portion 38. Next, an explanation will be given to the operation of the washing machine. In the washing or rinsing operation, the pulsator 6 is rotated with the washer/dehydrator tub 5 retaining therein water at a predetermined water level. When the pulsator 6 is rotated, water present between the under surface of the washer/dehydrator tub 5 and the upper surface of the outer tub 2 is pumped up through the through-holes 27 formed in the bottom of the washer/dehydrator tub 5 by the pumping action of the rear vanes 29. The pumped-up water is forced toward the periphery of the pulsator 6, then flows upward through the water circulation passage 17, and discharged into the washer/dehydrator tub 5 from the upper opening of the water circulation passage 17 through the lint filter 18. Upon actuation of the air pump 20, air is supplied into the first feed pipe 21. The supplied air passes through the connection pipe 22 and the second feed pipe 23, and is discharged in a bubble form into the outer tub 2 from the bubble outlet 24 provided in the bottom of the outer tub 2. The discharged air bubbles float up, and are directly sucked up into the through-holes 27 formed in the bottom of the washer/dehydrator tub 5 by the pumping action of the rear vanes 29 of the pulsator 6. Some of the air bubbles are once trapped in the recessed portion 26 formed in the bottom of the washer/dehydrator tub 5 and then sucked into the through-holes 27 to be supplied into the washer/dehydrator tub 5. More specifically, where the air bubbles discharged into the outer tub 2 from the bubble outlet 24 are not directly sucked into the through-holes 27, the air bubbles are once retained in the recessed portion 26 before being sucked into the through-holes 27. Therefore, the air bubbles are prevented from escaping outside the outer tub 2 not through the through-holes 27. Thus, the air bubbles can assuredly be supplied into the washer/dehydrator tub 5. The air bubbles having passed through the through-holes 27 are agitated by the rear vanes 29 provided on the rear surface of the pulsator 6 so as to be fined into fine air bubbles (about 10µm to 2mm in diameter, 0.5mm on average) which offer an improved washing effect. The fine air bubbles are accumulated in the three compartments 37a, 37b, 37c of each of the agitation vane mounting portions 32. Since the plurality of bubble outlet holes 38 extend vertically through the predetermined portions of the compartments 37a, 37b, 37c, the fine air bubbles 38 accumulated in the respective compartments 37a, 37b, 37c are discharged from the bubble outlet holes 38, and float up into the washer/dehydrator tub 5. At this time, the air bubbles fined by the rear vanes 29 are evenly accumulated in the three compartments 37a, 37b, 37c of each of the agitation vane mounting portions 32 and, therefore, fine air bubbles of substantially the same number are discharged from the respective bubble outlet holes 38 formed in the ceilings of the compartments 37a, 37b, 37c. More specifically, the rotation of the pulsator 6 exerts a centrifugal force on the air bubbles accumulated in the pulsator 6. If the inside spaces of the agitation vane mounting portions 32 were not radially divided, the air bubbles would be distributed heavily in the peripheral portion of the pulsator 6. Therefore, the number of air bubbles discharged from the bubble outlet holes located in the peripheral portions of the agitation vane mounting portions 32 would be greater than the number of air bubbles discharged from the bubble outlet holes located in the central portions of the agitation vane mounting portions 32. This is problematic because the air bubbles would non-uniformly be supplied to the clothes. In this embodiment, conversely, the inside spaces of the agitation vane mounting portions 32 are radially divided, so that the air bubbles are evenly accumulated in the separate compartments 37a, 37b, 37c. Therefore, the air bubbles are prevented from being distributed heavily in the peripheral portion of the pulsator 6. In this way, the air bubbles, which are substantially uniformly discharged from the respective bubble outlet holes 38 formed in the pulsator 6, are not distributed heavily to part of the clothes but uniformly throughout the clothes in the washing liquid. Thus, about 50 to 60 million fine air bubbles per minute are discharged from the bubble outlet holes 38 of the pulsator 6, and float up to come into contact with the clothes. When the air bubbles come into contact with the clothes to crush, ultrasonic waves are generated, and micro-vibration thereof causes dirt such as sebum adhering to fibers of the clothes to be easily dislodged from the fibers. Thus, the washing and rinsing effect is improved by utilizing the air bubbles and water currents generated by the pulsator 6, compared with a case where only the water currents are utilized for the washing and rinsing operations. Only one bubble outlet 24 is provided in this embodiment but, as another modification of the bubble outlet, a plurality of bubble outlets may be provided as shown in Fig. 5. The provision of the plurality of bubble outlets 24 ensures further uniform distribution of the air bubbles in the washer/dehydrator tub 5, thereby improving the washing and rinsing effect. There will next be described another embodiment of the present invention. Fig. 6 is a partial sectional view illustrating a lower portion of the outer tub. In the embodiment shown in Fig. 6, a rotation groove 6b, which comprises a plurality of cylindrical walls 6a, is provided on an outer circumferential portion of the pulsator 6 integrally therewith. An annular wall 5a, which is to be kept in a non-contact engagement with the rotary groove 6b with play, projects from a bottom portion of the washer/dehydrator tub 5 opposed to the outer circumferential portion of the pulsator 6 where the rotary groove 6b is provided. The rotary groove 6b and the annular wall 5a constitute a labyrinth seal 40. Because of a slight resistance at the bubble outlet holes 38, some of the air bubbles supplied to the rear side of the pulsator 6 and fined by the rear vanes 29 would otherwise leak from the circumferential portion of the pulsator 6 into the washer/dehydrator tub 5 not through the bubble outlet holes 38, while the other air bubbles would be discharged through the bubble outlet holes 38 into the washer/dehydrator tub 5. In this embodiment, however, the labyrinth seal 40, which keeps a sealing engagement between the circumferential portion of the pulsator 6 and the washer/dehydration tub 5, enables the air bubbles supplied to the rear side of the pulsator 6 to be contained in a space on the rear side of the pulsator 6. This more effectively prevents the air bubbles from leaking through the periphery of the pulsator 6 into the washer/dehydration tub 5. Thus, the air bubbles are supplied into the washer/dehydrator tub 5 only through the bubble outlet holes 38, whereby the bubble supply efficiency can be improved. Next, an explanation will be given to further another embodiment of the present invention. Although the rear vanes 29 for fining air bubbles are of a flat shape in the aforesaid embodiments, the rear vanes may be of an undulated shape as shown in Fig. 7 or of a comb shape as shown in Fig. 8. Fig. 7 is a top view illustrating a modification of the rear vanes, and Fig. 8 is a side view illustrating another modification of the rear vanes. In Figs. 7 and 8, components corresponding to those shown in Fig. 3 are denoted by the same reference characters. As shown in Fig. 7, rear vanes 29a each have an undulated shape as seen from the top of the pulsator 6. With this arrangement, the rear vanes 29a each have a greater surface area thereby to operate more effectively. Therefore, the rear vanes 29a can more efficiently fine the air bubbles supplied to the rear side of the pulsator 6. As shown in Fig. 8, rear vanes 29c each have a generally comb shape with a plurality of slits 29d formed in a lower edge portion thereof as seen laterally of the pulsator. With this arrangement, the rear vanes 29c each have a greater effective surface area, thereby offering an improved bubble fining effect. There will next be explained a modification of the bubble outlet holes. Although the bubble outlet holes 38 are generally uniformly distributed over the pulsator 6 as shown in Fig. 3 in the aforesaid embodiments, the bubble outlet holes may have different open areas and may be arranged at different intervals. When the pulsator 6 is rotated, part of the washing liquid present on the rear side of the pulsator 6 flows toward the periphery of the pulsator 6. The flow speed of the washing liquid and hence the amount of air bubbles progressively increase toward the periphery of the pulsator 6. Therefore, the air bubbles supplied through the through-holes 27 and fined by the rear vanes 29 tend to be distributed heavily in the peripheral portion of the pulsator 6. Where the bubble outlet holes 38 are uniformly provided over the pulsator 6 as in the aforesaid embodiments, the air bubbles are supplied into the washer/dehydrator tub 5 in a greater amount through the bubble outlet holes 38 located in the peripheral portion of the pulsator 6 than through the bubble outlet holes 38 located in the central portion. Therefore, the air bubbles gather in the bubble outlet holes 38 in the peripheral portion of the pulsator 6. This may prevent smooth flow of the air bubbles, failing to efficiently supply the air bubbles. To overcome this problem, a spacing between two radially adjacent bubble outlet holes 38a may progressively be reduced toward the periphery of the pulsator 6 to increase the distribution density of the bubble outlet holes 38a in the peripheral portion of the pulsator. That is, the total open area of the bubble outlet holes 38a present in the peripheral portion is greater than the total open area of the bubble outlet holes present in the central portion. Therefore, even if the air bubbles gather in the bubble outlet holes 38a in the peripheral portion of the pulsator 6 by the rotation of the pulsator 6, the air bubbles smoothly pass through the bubble outlet holes 38a. Thus, efficient supply of the air bubbles can be ensured. While the embodiments of the present invention have thus been described in detail, it should be understood that these embodiments are merely illustrative of the technical principles of the present invention but not limitative of the same. The spirit and scope of the present invention are to be limited only by the appended claims. This application claims the conventional priority benefits on the basis of Japanese Patent Applications No. 10-224484 and No. 11-118522 filed to the Japanese Patent Office on August 7, 1998 and April 26, 1999, respectively, the disclosure thereof being incorporated herein by reference. WE CLAIM : 1 A washing machine with bubble fixing means comprising: bubble generating means (20) for supplying air bubbles into washing liquid within a washer tub (2, 5); bubble fining means (6, 29) for fining the air bubbles supplied into the washing liquid by the bubble generating means (20); and a pulsator (6) provided within the washer tub (2, 5), wherein the air bubbles and water currents generated by the pulsator (6) are utilized in combination for clothes washing and rinsing operations, and wherein the pulsator (6) bubble outlet hole (38) for feeding upward within the washer tub (2, 5) the air bubbles supplied into the washing liquid by the bubble generating means (20); characterized in that the bubble fining means (6, 29) is a vane (29) provided on an under surface of the pulsator (6). 2. A washing machine as claimed in claim 1, wherein said rear vane (29) is disposed radially of the pulsator (6) on the under surface of the pulsator (6). 3. A washing machine as claimed in claim 2, wherein said rear vane (29) is a plurality of rear vanes (29) disposed radially of the pulsator (6). 4. A washing machine as claimed in claim 1, wherein the pulsator (6) has a plurality of compartments (37a, 37b, 37c) .__. provided on a rear side thereof and radially separated from each other, the compartments (37a, 37b, 37c) each having the bubble outlet hole (38) in a ceiling thereof. 5. A washing machine as claimed in any of claims 1 to 4, wherein the washer tub (2, 5) is provided with a washer/dehydrator tub (5) , capable of retaining water therein, an outer tub (2) of said washing tub (2, 5) has a bubble outlet (24) provided on a lower wall portion thereof for introducing the air bubbles supplied from the bubble generating means (20) into said outer tub (2), and the washer/dehydrator tub (5) has a through-hole (27) formed in a lower wall portion thereof for introducing therein the air bubbles supplied into the washing liquid. 6. A washing machine as claimed in claim 5, wherein the pulsator (6) is rotatably provided on the bottom of the washer/dehydrator tub (5), wherein the washer/dehydrator tub (5) has a portion (26) upwardly recessed in the bottom thereof, the bubble outlet (24) opens adjacent the recessed portion (26), wherein the through-hole (27) is provided in the recessed portion (26) so that the air bubbles supplied from the bubble outlet (24) is introducible into the washer/dehydrator tub (5). 7 A washing machine as claimed in claim 5 or 6, wherein the outer tub (2) is supported in a vibro-insulating manner by an outer frame (1), wherein the bubble generating means (20) has an air supplying means provided above a main body of the washing machine, and an air feed line (21, 23) which connects the air supplying means (20) to the bubbles outlet (24), where in the air feed line (21, 23) being divided into an upper feed line (21) and a lower feed line (23) which are connected by a connector (22) provided adjacent a side wall of the outer tub (2). 8 A washing machine as claimed in claim 7, wherein the upper feed line (21) is connected horizontally to the lower feed line (23) by the connector (22). 9. A washing machine as claimed in claim 7 or 8, wherein the upper feed line (21) is formed of a flexible material. 10. A washing machine as claimed in any of claims 7 or 9, wherein the lower feed line (23) has an inside diameter greater than that of the upper feed line (21). 11. A washing machine as claimed in any of claims 1 to 10, wherein the bubble fining means (6, 29) has sealing means (40) provided between the pulsator (6) and the washer tub (2, 5) for preventing the air bubbles supplied into the washing liquid from leaking from other portions than that bubble outlet holes (38) formed in the pulsator (6). 12 A washing machine as claimed in claim 11, wherein the sealing means consist of a labyrinth mechanism (40) which has a groove (6b) having a plurality of cylindrical walls (6a) provided on either one of an outer circumferential portion of the pulsator (6) and a bottom wall portion of the washer tub (2, 5) opposed to the outer circumferential portion of the pulsator (6), and an annular wall (5a) provided on the other in a non-contact engagement with an open portion of the groove (6b) with play. 13. A washing machine as claimed in any of claims 1 to 12, wherein the bubble outlet hole (38) provided in the pulsator (6) has a plurality of bubble outlet holes (38), wherein the total open area of bubble outlet holes (38) located in a central portion of the pulsator (6) is smaller than a total open area of bubble outlet holes (38) located in a peripheral portion of the pulsator (6). 14 A washing machine as claimed in any of claims 5 to 13, wherein the bubble outlet (24) is provided with a check-valve (24a) for preventing the washing liquid from flowing back into the air feed line (21, 23) from the outer tub (2). 15. A washing machine with bubble fixing means substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

Full Text

The present invention relates to a washing machine with bubble forming means and, more particularly, to a -washing machine which has a bubble generator for generating air bubbles in a washer tub during washing and rinsing operations.
Description of Related Art
Washing machines are conventionally known which utilize not only water currents of washing liquid within a washer tub generated by rotation of a pulsator but also a great amount of air bubbles supplied into the washing liquid for washing and rinsing clothes (see Japanese Unexamined Patent Publication No. 7-47188 (1995), for example). In such a washing machine, when air bubbles come into contact with clothes thereby to crush, ultrasonic waves are generated, and micro-vibration thereof causes dirt to be dislodged from clothes. This offers a higher washing effect than a case where air bubbles are not applied to the clothes. Further, the air bubbles come into gaps between clothes to offer a cushioning effect. Tb.is prevents superfluous friction for suppression of wear of the clothes. In addition, the air bubbles cause the clothes to float in the washing liquid, so that the clothes are less
liable to stagnate in the bottom of the washer tub. This prevents the clothes from being damaged by friction which may otherwise be caused between the pulsator and the clothes. However, the washing machines adapted to perform the washing operation by supplying air bubbles has the following drawbacks.
1. If the air bubbles supplied into the washing liguid have
a greater size, the air bubbles coming into contact with the
clothes do not crush thereby to be accumulated under the
clothes. In such an event, the clothes are merely floated up,
so that no improvement in the washing effect by the air
bubbles is expected.
Further, larger air bubbles are hardly distributed throughout the clothes, thereby failing to improve the washing effect.
2. Some washing machines are constructed such that air
supplied from an air pump is discharged as air bubbles into a
washer/dehydrator tub from bubble outlet holes formed in a
pulsator. In this case, a centrifugal force generated by the
rotation of the pulsator acts on air bubbles accumulated on
the rear side of the pulsator, so that the air bubbles are
distributed heavily in a peripheral portion of the pulsator by
the centrifugal force. Therefore, the number of air bubbles
discharged from bubble outlet holes located in the peripheral
portion of the pulsator is greater than the number of air
bubbles discharged from bubble outlet holes located in a central portion of the pulsator. This results in a nonuniform air bubble distribution in the washer/dehydrator tub, whereby the air bubbles cannot uniformly be supplied toward clothes.
3. A so-called automatic washing machine includes a washer/dehydrator tub rotatably supported in an outer tub. In such an automatic washing machine, a conventional arrangement for bubble supply to the washer/dehydrator tub includes a bubble outlet located in the lower portion of the outer tub (between an outer bottom portion of the washer/dehydrator tub and an inner bottom portion of the outer tub), and through-holes formed in the bottom of the washer/dehydrator tub and a pulsator. That is, air bubbles from the bubble outlet are supplied into the washer/dehydrator tub through the through-holes .
However, some of the air bubbles supplied from the bubble outlet are deflected in unintended directions, failing to pass through the through-holes formed in the washer/dehydrator tub.
In such an event, the air bubbles supplied from the bubble outlet flow out of the washer/dehydrator tub along the outer bottom surface thereof (into a space between the washer/dehydrator tub and the outer tub), so that the air bubbles are not supplied into the washer/dehydrator tub. 4. The bubble outlet is located on a side wall of the outer
tub at a level lower than the bottom of the washer/dehydrator tub, and connected to an air pump via a feed pipe outside the outer tub. Therefore, when the air pump is off, washing liquid or rinsing water comes into the feed pipe, so that dirt, undissolved detergent and the like dislodged from clothes may be accumulated or deposited within the feed pipe thereby to clog the feed pipe. This is problematic in the generation of air bubbles.
5. The air pump is provided remotely from the outer tub (for example, in a top panel located above the outer tub), and the feed pipe extends from the air pump to the bubble outlet located in the lower portion of the outer tub with opposite ends thereof being respectively connected to an outlet of the air pump and the bubble outlet. Therefore, the feed pipe is liable to be bent due to vibration of the outer tub during the operation of the washing machine. When the feed pipe is bent to the extreme, the feed pipe is flattened so that the air supply from the air pump is reduced or stopped, failing to sufficiently supply air bubbles into the washing liquid.
6. The air pump is provided in the top panel of an outer housing, and the outlet of the air pump is connected to the bubble outlet at the lower portion of the outer tub via the feed pipe. Since the feed pipe extends to the lower portion of the outer tub, the connection of the feed pipe to the lower portion of the outer tub is troublesome after incorporation of
the outer tub in the outer housing. Therefore, the production of the washing machine is complicated.
SUMMARY OF THE INVENTION
It is a first object of the present invention to provide a washing machine which ensures proper supply of air bubbles.
It is a second object of the present invention to provide a washing machine which offers improved washing and rinsing effects by utilizing air bubbles.
It is a third object of the present invention to provide a washing machine which can easily be produced with an improved air bubble feed line arrangement.
It is a fourth object of the present invention to provide a washing machine which is free from disturbance of air bubble supply which may otherwise occur due to vibration of the machine during operation thereof.
It is a fifth object of the present invention to provide a washing machine which is free from clogging of. an air bubble feed line.
It is a sixth object of the present invention to provide a washing machine which is capable of supplying air bubbles as much as possible into a washer tub through bubble outlet holes formed in a pulsator.
Accordingly, there is provided a washing machine with bubble fixing means comprising:
bubble generating means for supplying air bubbles into washing liquid within a washer tub;
bubble fining means for fining the air bubbles supplied into the washing liquid by the bubble generating means; and
a pulsator provided within the washer tub, wherein the air bubbles and water currents generated by the pulsator are utilized in combination for clothes washing and rinsing operations, and wherein the pulsator bubble outlet hole for feeding upward within the washer tub the air bubbles supplied into the washing liquid by the bubble generating means; characterized in that
the bubble fining means is a vane provided on an under surface of the pulsator.
Since the washing machine includes the bubble fining
means for fining the air bubbles supplied into the washing liquid by the bubble generating means, dissolution of a detergent in the washing liquid within the- washer tub is promoted, and clothes washing and rinsing effects are improved by micro-vibration (ultrasonic waves) caused when the fine air bubbles come into contact with clothes to be fined and crushed.
The washing machine preferably further comprises a pulsator provided within the washer tub and utilizes, in combination, the air bubbles and water currents generated by the pulsator for clothes washing and rinsing operations. In this case, the bubble fining means is preferably provided in the pulsator.
With this arrangement, the air bubbles supplied into the washing liquid by the bubble generating means are fined by the pulsator. Since the pulsator which is rotated during the washing and rinsing operations is utilized for the fining of the air bubbles, there is no need for provision of additional bubble fining means.
The bubble fining means may be a rear vane provided on an under surface of the pulsator. With this arrangement, the air
bubbles are more effectively fined.
In this case, the rear vane may be disposed radially on the under surface of the pulsator. It is further preferred that a plurality of such rear vanes are radially provided.
The rear vane preferably has a comb shape or an undulated shape. Thus, the rear vane has a greater effective area to improve the bubble fining effect.
The pulsator preferably has a bubble outlet hole for feeding upward the air bubbles supplied into the washing liquid by the bubble generating means within the washer tub.
In this case, the pulsator has a plurality of compartments which are provided on the rear side (i.e., under side) thereof and radially separated from each other. The compartments each preferably have the bubble outlet hole formed in the ceiling thereof.
With this arrangement, the air bubbles supplied below the pulsator by the bubble generating means such as an air pump are accumulated in the respective compartments separated from each other in the pulsator, so that the air bubbles are prevented from being distributed heavily in a peripheral portion of the pulsator due to a centrifugal force generated by rotation of the pulsator. Therefore, the air bubbles are substantially uniformly discharged from the respective bubble outlet holes of the pulsator, whereby the air bubbles are uniformly distributed throughout the clothes in the washing
liquid without heavy distribution of the air bubbles in a particular portion within the washer tub.
The washer tub may include a washer/dehydrator tub, and an outer tub enclosing the washer/dehydrator tub and capable of retaining water therein. In this case, it is preferred that the outer tub has a bubble outlet provided on a lower wall portion thereof for introducing the air bubbles supplied by the bubble generating means into the outer tub, and the washer/dehydrator tub has a through-hole formed in a lower wall portion thereof for introducing therein the air bubbles supplied into the washing liquid.
In this case, it is preferred that the pulsator is rotatably provided on the bottom of the washer/dehydrator tub, and the washer/dehydrator tub has a portion upwardly recessed in the bottom thereof. Further, it is preferred that the bubble outlet opens adjacent the recessed portion (preferably below the recessed portion), and the through-hole is provided in the recessed portion so that the air bubbles supplied from the bubble outlet can be introduced into the washer/dehydrator tub.
With this arrangement, the air bubbles introduced from the bubble outlet are accumulated in the recessed portion and then supplied into the washer/dehydrator tub through the through-hole. This prevents the air bubbles from flowing out of the washer/dehydrator tub not through the through-hole, so

that the air bubbles are assuredly supplied into the washer/dehydrator tub.
The outer tub may be supported in a vibro-insulating manner by an outer frame, and the bubble generating means may include an air supplying means provided above a main body of the washing machine. An air feed line may further be provided which connects the air supplying means to the bubble outlet. In this case, it is preferred that the air feed line is divided into an upper feed line and a lower feed line, which are connected by a connector provided adjacent a side wall of the outer tub.
Thus, the upper feed line of the air feed line can easily be connected to the lower feed line by accessing from an upper opening of the outer frame after the outer tub is incorporated in the outer housing in the production of the washing machine. The outer tub can be incorporated in the outer frame after the lower feed line has been disposed below the outer tub to be connected to a bottom portion of the outer tub. Thus, easier production of the washing machine is ensured because a producer does not have to access the bottom of the outer tub which is less accessible. In this connection, it is preferable that the connector is provided at a higher level than the bottom of the outer tub, and more preferably at a higher level than the bottom of the washer/dehydrator tub.
The upper feed line is preferably connected horizontally
to the lower feed line by the connector.
With this arrangement, even if the outer tub is vibrated, the upper feed line is less susceptible to a force horizontally exerted thereto at the connector in a line withdrawing direction. This prevents a failure in bubble supply and leakage of the washing liquid from the washer/dehydrator tub through the connector, which may otherwise occur due to withdrawal of the upper feed line from the lower feed line.
The upper feed line is preferably formed of a flexible material. Thus, the vibration of the outer tub caused during the operation of the washing machine is absorbed by the upper feed line, so that the decrease or cease of air supply from the air supplying means can be prevented which may otherwise occur due to the bending of the air feed line.
The lower feed line preferably has an inside diameter greater than the upper feed line. Even if the washing liquid comes into the lower feed line when the air supplying means is off, the lower feed line is less susceptible to clogging with dust, lint, undissolved detergent and the like contained in the washing liquid.
The washing machine preferably further includes sealing means provided between the pulsator and the washer tub for preventing the air bubbles supplied into the washing liquid from leaking from other portions than the bubble outlet holes
formed in the pulsator.
Thus, the air bubbles supplied to the rear side of the pulsator are prevented from leaking into the washer tub from a gap between the pulsator and the washer tub, so that the air bubbles are uniformly discharged from the bubble outlet holes.
The sealing means is preferably a non-contact sealing mechanism. For example, it is preferred that the sealing means is comprised of a labyrinth mechanism which includes a groove comprising a plurality of cylindrical walls provided on either one of an outer circumferential portion of the pulsator and a bottom wall portion of the washer tub opposed to the outer circumferential portion of the pulsator, and an annular wall provided on the other in a non-contact engagement with an open portion of the groove with play.
The bubble outlet hole provided in the pulsator preferably includes a plurality of bubble outlet holes. In this case, the total open area of bubble outlet holes located in a central portion of the pulsator is preferably smaller than the total open area of bubble outlet holes located in a peripheral portion of the pulsator.
Since the speed of water flow progressively increases toward the periphery of the pulsator on the rear side thereof, the supply of air bubbles is correspondingly increases toward the periphery thereof. With the total open area of the bubble outlet holes in the peripheral portion being greater than the
total open area of the bubble outlet holes in the central portion, the air bubbles can be supplied as much as possible into the washer tub.
Where the outer tub is supported in a vibro-insulating manner by the outer frame and the bubble outlet is connected to the air supplying means through the air feed line, the bubble outlet is preferably provided with a check-valve for preventing the washing liquid from flowing back into the air feed line from the outer tub. Thus, dust, detergent and the like are prevented from coming into the air feed line, thereby preventing the reduction in the supply of the air bubbles which may otherwise occur due to clogging of the air feed line.
The bubble fining means is preferably capable of generating fine air bubbles having a diameter of about 0.5mm.
If the diameter of the fine air bubbles is too small, the air bubbles pass through fiber gaps of clothes and do not easily crush in contact with the clothes, thereby failing to improve the washing effect. If the diameter of the air bubbles is too large, the air bubbles do not crush in contact with the clothes, but are liable to be accumulated under the clothes thereby to float up the clothes. Therefore, the air bubbles preferably have a diameter of about 0.5mm.
With emphasis on the sealing mechanism provided between the pulsator and the washer tub, the present invention is
embodied as a washing machine which comprises a washer tub, bubble generating means for supplying air bubbles into washing liquid within the washer tub, a pulsator provided within the washer tub and having a bubble outlet hole for supplying into the washer tub the air bubbles supplied into the washing liquid by the bubble generating means, and sealing means provided between the pulsator and the washer tub for preventing the supplied air bubbles from leaking from other portions than the bubble outlet hole into the washer tub.
In this case, the sealing means may, for example, be comprised of a labyrinth mechanism which includes a groove comprising a plurality of cylindrical walls provided on either one of an outer circumferential portion of the pulsator and a bottom wall portion of the washer tub opposed to the outer circumferential portion of the pulsator, and an annular wall provided on the other in a non-contact engagement with an open portion of the groove with play.
With emphasis on the effective supply of air bubbles into the washer tub, the present invention is embodied as a washing machine which comprises a washer tub, bubble generating means for supplying air bubbles into washing liquid within the washer tub, and a pulsator provided within the washer tub and having a plurality of bubble outlet holes for supplying into the washer tub the air bubbles supplied into the washing liquid by the bubble generating means, wherein the total open
area of bubble outlet holes located in a central portion of the pulsator is smaller than the total open area of bubble outlet holes located in a peripheral portion of the pulsator.
With emphasis on the mechanism for the prevention of the air feed line clogging, the present invention is embodied as a washing machine which comprises an outer tub supported within an outer frame in a vibro-insulating manner, a washer/dehydrator tub disposed within the outer frame, air supplying means for supplying air bubbles into washing liquid, a bubble outlet provided on a lower wall portion of the outer tub for supplying the air bubbles into the outer tub, a air feed line connecting the air supplying means to the bubble outlet, and a check-valve provided in the bubble outlet for preventing the washing liquid from flowing back into the air feed line from the outer tub.
The foregoing and other objects, features and effects of the present invention will become more apparent from the following description of the preferred embodiments with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a side sectional view illustrating the overall construction of a washing machine according to one embodiment of the present invention;
Fig. 2 is a partial sectional view of the washing

machine;
Fig. 3A is a plan view of a pulsator, Fig. 3B is a. sectional view taken along a line A-B in Fig. 3A, and Fig. 3C is a sectional view taken along a line D-F in Fig. 3B;
Fig. 4 is a partial sectional view illustrating one exemplary bubble outlet arrangement;
Fig. 5 is a partial sectional view illustrating another exemplary bubble outlet arrangement;
Fig. 6 is a partial sectional view illustrating a washing machine according to another embodiment of the invention;
Fig. 7 is a top view illustrating one exemplary rear vane arrangement;
Fig. 8 is a side view illustrating another exemplary rear vane arrangement; and
Fig. 9 is a partial sectional view illustrating one exemplary bubble outlet hole arrangement.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Fig. 1 is a side sectional view illustrating the overall construction of a washing machine according to a first embodiment of the present invention, and Fig. 2 is a partial sectional view of the washing machine. An outer tub 2 is suspendedly supported by a plurality of suspension rods 3 within an outer housing 1 which constitutes an outer frame of the washing machine. This prevents vibration of the outer tub
2 from being transferred to the outer housing 1.
Within the outer tub 2, a washer/dehydrator tub 5 having a multiplicity of perforations 4 formed in a circumferential wall thereof is rotatably supported about a rotation shaft provided on the bottom of the outer tub 2. A pulsator 6 for agitating clothes to be washed is provided on the bottom of the washer/dehydrator tub 5. A torque of a motor 7 provided below the outer tub 2 is transmitted to the washer/dehydrator tub 5 and the pulsator 6 via a motor pulley 8, a V-belt 9, a main pulley 10 and a power switching mechanism 11.
The power switching mechanism 11 switches the coupling of a driving shaft in such a manner that the washer/dehydrator tub 5 and the pulsator 6 are rotated in unison during a dehydration operation and, otherwise, only the pulsator 6 is rotated.
A water supplying mechanism not shown is provided above the outer housing 1 for supplying water into the washer/dehydrator tub 5.
A drainage port 12 is provided in a bottom portion of the outer tub 2, and connected to a drainage hose 15 via a drainage valve 13 and a drainage line 14. The drainage valve 13 is provided with a solenoid not shown. When the solenoid is energized, the drainage valve 13 is opened, and a clutch in the power switching mechanism 11 is operated to couple the washer/dehydrator tub 5 to the pulsator 6. Thus, the power
switching mechanism 11 permits only the pulsator 6 to be rotated when the drainage valve 13 is closed, and permits the washer/dehydrator tub 5 and the pulsator 6 to be rotated in unison when the drainage valve 13 is open.
An annular balance ring 16 for vibro-insulation is attached to an upper edge of the washer/dehydrator tub 5. A water circulation passage 17 is provided along an inner wall portion of the washer/dehydrator tub 5 as extending vertically from the bottom of the washer/dehydrator tub 5 to just below the balance ring 16. A lint filter 18 for trapping dust such as lint in the washing liquid is detachably attached to an upper opening of the water circulation passage 17.
An air pump 20 for bubble generation is incorporated in a top panel 19, and an air outlet 20a of the air pump 20 is connected to one end of a first feed pipe 21. The first feed pipe 21 is wound, with some slack, around one of the suspension rods 3 suspending the outer tub 2 outside the outer tub 2. The other end of the first feed pipe 21 is connected horizontally to a connection pipe 22 provided on a side wall of the outer tub 2.
Since the connection of the first feed pipe 21 is provided on the side wall of the outer tub 2, the first feed pipe 21 can be connected to the connection pipe 22 after the outer tub 2 is incorporated in the outer housing 1. Therefore, the productivity of the washing machine is
improved.
A second feed pipe 23 is connected to a lower end of the connection pipe 22, and extends along a bottom portion of the outer tub 2 to a bubble outlet 24. The second feed pipe 23 is firmly fixed to the outer tub 2 and connected to the bubble outlet 24. Thus, the second feed pipe 23 vibrates along with the outer tub 2 when the outer tub 2 is vibrated, so that the second feed pipe 23 will never be inadvertently bent to close the passage therein.
The first feed pipe 21 is an elastic tube such as of a rubber having an inside diameter of about 3.5mm. On the other hand, the second feed pipe 23 is a tube having an inside diameter of about 7.2mm. The first feed pipe 21 having a smaller inside diameter is less liable to be bent than the second feed pipe 23 having a greater inside diameter and, therefore, is advantageous in that the passage inside the pipe 21 is less liable to be flattened to be closed. However, the smaller inside diameter of the first feed pipe 21 presents a drawback that the pipe 21 is susceptible to clogging with dust and the like. Conversely, the second feed pipe 23 having a greater inside diameter is liable to be bent thereby to be closed, but insusceptible to clogging with dust because of its greater inside diameter.
That is, an upper portion of the feed line is liable to be vibrated together with the outer tub 2 but is less
susceptible to intrusion of the washing liquid. Therefore, the upper portion is constituted by the tube which is less liable to be bent but may be susceptible to clogging with dust. On the other hand, a lower portion of the feed line need not absorb the vibration of the outer tub without the fear of bending due to the vibration of the outer tub but is liable to be clogged with dust. Therefore, the lower portion is constituted by the tube which is insusceptible to clogging with dust but may be liable to be bent.
Since the clothes are agitated in the washing liquid within the washer/dehydrator tub 5 with the pulsator 6 being rotated on the bottom of the washer/dehydrator tub 5 during the washing and rinsing operations, the outer tub 2 vibrates vertically and laterally. During the dehydration operation, much greater vibration is generated. When the outer tub 2 is vibrated, a force liable to bend the first feed pipe 21 is exerted thereon, because the lower end of the first feed pipe 21 is connected to the connection pipe 22 fixed to the outer tub 2 and the upper end thereof is connected to the air pump 20 disposed in the top panel 19.
However, the first feed pipe 21 which is comprised of the smaller inside diameter tube as described above will never be bent at an acute angle to close the air passage defined therein even if the outer tub 2 is vibrated.
Further, the lower end of the first feed pipe 21 is
connected horizontally to the connection pipe 22. The horizontal connection between the first feed pipe 21 and the connection pipe 22 is hardly subjected to a force exerted in such a direction as to withdraw the first feed pipe 21 from the connection pipe 22 even if the outer tub 2 is vibrated during the operation of the washing machine. This prevents a failure in air supply and leakage of the washing liquid from the washer/dehydrator tub 5 through the connection pipe 22, which may otherwise occur due to the withdrawal of the first feed pipe 21 from the connection pipe 22.
Dust and lint dislodged from the clothes, undissolved detergent and the like may settle on the bottom of the outer tub 2. Where no air is supplied to the feed pipes 21, 23 with the air pump being off (e.g., during the rinsing operation and the dehydration operation), the washing liquid easily comes into the second feed pipe 23 through the bubble outlet 24. If the dust, lint, undissolved detergent and the like in the incoming washing liquid are deposited and accumulated on an interior surface of the second feed pipe 23, the second feed pipe 23 may be clogged therewith, so that the air supply may be reduced or stopped.
However, the second feed pipe 23 is comprised of the greater inside diameter tube as described above and therefore, even if the washing liquid comes into the second feed pipe 23, the second feed pipe 23 is less liable to be clogged with the
dust, lint and undissolved detergent in the washing liquid.
The second feed pipe 23 is comprised of the tube in this embodiment but may, for example, be comprised of a duct which is formed integrally with the bottom portion of the outer tub 2 and has a sectional area large enough to be free from clogging with the dust, lint and the like.
According to a modification of the bubble outlet as shown in Fig. 4, the bubble outlet 24 is provided with a check-valve 24a for preventing the washing liquid from flowing back from the outer tub 2 toward the air pump 20 through the feed pipe 23. This arrangement permits the air from the air pump 20 to be supplied into the outer tub 2, but does not permit the washing liquid to flow back into the feed pipe 23. Therefore, the dust, lint, undissolved detergent and the like in the washing liquid are prevented from being deposited within the feed pipe 23.
Since the washing liquid is prevented from coming into the feed pipe 23, a freeze problem in winter can be avoided which may otherwise occur due to washing liquid remaining in the feed pipe 23.
An upwardly recessed portion 26 having a donut-like shape is formed on the bottom of the washer/dehydrator tub 5 as surrounding a rotation shaft 25 of the washer/dehydrator tub 5. On the bottom of the washer/dehydrator tub 5, the recessed portion 26 is formed with a plurality of through-holes 27 for
communication of the washing liquid between the washer/dehydrator tub 5 and the outer tub 2 and for passage of the bubbles of the air from the air pump 20. The through-holes 27 are located above the bubble outlet 24. The bubbles of the air supplied by the air pump 20 through the bubble outlet 24 come into the washer/dehydrator tub 5 through the through-holes 27. Some of the bubbles are once trapped in the recessed portion 26 and then come into the washer/dehydrator tub 5 through the through-holes 27.
Figs. 3A to 3C are diagrams illustrating the pulsator 6 in detail, particularly, Fig. 3A is a top plan view of the pulsator 6, Fig. 3B is a sectional view taken along a line A-B in Fig. 3A, and Fig. 3C is a sectional view taken along a line D-F in Fig. 3B.
The pulsator 6 includes agitation vanes 28 provided on its upper surface for generating water currents within the washer/dehydrator tub 5, and rear vanes 29 formed radially on its under surface. The rear vanes 29 have the function of pumping up part of the washing liquid present between the washer/dehydrator tub 5 and the outer tub 2. The rear vanes 29 also have the function of fining the air bubbles generated from the bubble outlet 24.
The pulsator 6 comprises a generally disk-shaped pulsator body 30 and the plurality of agitation vanes 28 attached to the body 30.
The pulsator body 30 is a generally disk-shaped one-piece member formed of a resin material, and includes a boss 31 projecting upward for mounting the pulsator 6 to the rotation shaft. The pulsator body 30 has five agitation vane mounting portions 32 radially formed around the boss 31 at generally equidistant angular intervals on the upper surface thereof, and flat portions 33 between each adjacent pair of agitation vane mounting portions, each of the flat portions 33 being provided with a slightly concaved portion in a generally radially middle portion thereof. The pulsator body 30 further has drainage holes 34 formed in the flat portions 33 thereof for communication between the upper and lower sides of the pulsator body 30, and water ejection holes 35 formed in a peripheral portion thereof.
A peripheral rib 36 is provided circumferentially on an under surface of the pulsator body 30 as projecting downward, and the plurality of rear vanes 29 are provided as extending radially (i.e., in pulsator radial directions) from the boss
31 to the peripheral rib 36. The agitation vane mounting
portions 32 protrude upward from the flat portions 33 in a
generally inverted-U-shape, and the agitation vanes 28 are
mounted on top of the agitation vane mounting portions 32.
The inside spaces of the agitation vane mounting portions
32 are each divided into three compartments 37a, 37b, 37c, and
bubble outlet holes 38 for ejecting air bubbles are formed in
ceilings of the respective compartments 37a, 37b, 37c as extending through the agitation vane 28 and the agitation vane mounting portion 38.
Next, an explanation will be given to the operation of the washing machine.
In the washing or rinsing operation, the pulsator 6 is rotated with the washer/dehydrator tub 5 retaining therein water at a predetermined water level. When the pulsator 6 is rotated, water present between the under surface of the washer/dehydrator tub 5 and the upper surface of the outer tub 2 is pumped up through the through-holes 27 formed in the bottom of the washer/dehydrator tub 5 by the pumping action of the rear vanes 29. The pumped-up water is forced toward the periphery of the pulsator 6, then flows upward through the water circulation passage 17, and discharged into the washer/dehydrator tub 5 from the upper opening of the water circulation passage 17 through the lint filter 18.
Upon actuation of the air pump 20, air is supplied into the first feed pipe 21. The supplied air passes through the connection pipe 22 and the second feed pipe 23, and is discharged in a bubble form into the outer tub 2 from the bubble outlet 24 provided in the bottom of the outer tub 2. The discharged air bubbles float up, and are directly sucked up into the through-holes 27 formed in the bottom of the washer/dehydrator tub 5 by the pumping action of the rear
vanes 29 of the pulsator 6. Some of the air bubbles are once trapped in the recessed portion 26 formed in the bottom of the washer/dehydrator tub 5 and then sucked into the through-holes 27 to be supplied into the washer/dehydrator tub 5.
More specifically, where the air bubbles discharged into the outer tub 2 from the bubble outlet 24 are not directly sucked into the through-holes 27, the air bubbles are once retained in the recessed portion 26 before being sucked into the through-holes 27. Therefore, the air bubbles are prevented from escaping outside the outer tub 2 not through the through-holes 27. Thus, the air bubbles can assuredly be supplied into the washer/dehydrator tub 5.
The air bubbles having passed through the through-holes 27 are agitated by the rear vanes 29 provided on the rear surface of the pulsator 6 so as to be fined into fine air bubbles (about 10µm to 2mm in diameter, 0.5mm on average) which offer an improved washing effect. The fine air bubbles are accumulated in the three compartments 37a, 37b, 37c of each of the agitation vane mounting portions 32. Since the plurality of bubble outlet holes 38 extend vertically through the predetermined portions of the compartments 37a, 37b, 37c, the fine air bubbles 38 accumulated in the respective compartments 37a, 37b, 37c are discharged from the bubble outlet holes 38, and float up into the washer/dehydrator tub 5.
At this time, the air bubbles fined by the rear vanes 29 are evenly accumulated in the three compartments 37a, 37b, 37c of each of the agitation vane mounting portions 32 and, therefore, fine air bubbles of substantially the same number are discharged from the respective bubble outlet holes 38 formed in the ceilings of the compartments 37a, 37b, 37c.
More specifically, the rotation of the pulsator 6 exerts a centrifugal force on the air bubbles accumulated in the pulsator 6. If the inside spaces of the agitation vane mounting portions 32 were not radially divided, the air bubbles would be distributed heavily in the peripheral portion of the pulsator 6. Therefore, the number of air bubbles discharged from the bubble outlet holes located in the peripheral portions of the agitation vane mounting portions 32 would be greater than the number of air bubbles discharged from the bubble outlet holes located in the central portions of the agitation vane mounting portions 32. This is problematic because the air bubbles would non-uniformly be supplied to the clothes. In this embodiment, conversely, the inside spaces of the agitation vane mounting portions 32 are radially divided, so that the air bubbles are evenly accumulated in the separate compartments 37a, 37b, 37c. Therefore, the air bubbles are prevented from being distributed heavily in the peripheral portion of the pulsator 6.

In this way, the air bubbles, which are substantially uniformly discharged from the respective bubble outlet holes 38 formed in the pulsator 6, are not distributed heavily to part of the clothes but uniformly throughout the clothes in the washing liquid.
Thus, about 50 to 60 million fine air bubbles per minute are discharged from the bubble outlet holes 38 of the pulsator 6, and float up to come into contact with the clothes. When the air bubbles come into contact with the clothes to crush, ultrasonic waves are generated, and micro-vibration thereof causes dirt such as sebum adhering to fibers of the clothes to be easily dislodged from the fibers. Thus, the washing and rinsing effect is improved by utilizing the air bubbles and water currents generated by the pulsator 6, compared with a case where only the water currents are utilized for the washing and rinsing operations.
Only one bubble outlet 24 is provided in this embodiment but, as another modification of the bubble outlet, a plurality of bubble outlets may be provided as shown in Fig. 5. The provision of the plurality of bubble outlets 24 ensures further uniform distribution of the air bubbles in the washer/dehydrator tub 5, thereby improving the washing and rinsing effect.
There will next be described another embodiment of the present invention. Fig. 6 is a partial sectional view
illustrating a lower portion of the outer tub. In the embodiment shown in Fig. 6, a rotation groove 6b, which comprises a plurality of cylindrical walls 6a, is provided on an outer circumferential portion of the pulsator 6 integrally therewith. An annular wall 5a, which is to be kept in a non-contact engagement with the rotary groove 6b with play, projects from a bottom portion of the washer/dehydrator tub 5 opposed to the outer circumferential portion of the pulsator 6 where the rotary groove 6b is provided. The rotary groove 6b and the annular wall 5a constitute a labyrinth seal 40.
Because of a slight resistance at the bubble outlet holes 38, some of the air bubbles supplied to the rear side of the pulsator 6 and fined by the rear vanes 29 would otherwise leak from the circumferential portion of the pulsator 6 into the washer/dehydrator tub 5 not through the bubble outlet holes 38, while the other air bubbles would be discharged through the bubble outlet holes 38 into the washer/dehydrator tub 5.
In this embodiment, however, the labyrinth seal 40, which keeps a sealing engagement between the circumferential portion of the pulsator 6 and the washer/dehydration tub 5, enables the air bubbles supplied to the rear side of the pulsator 6 to be contained in a space on the rear side of the pulsator 6. This more effectively prevents the air bubbles from leaking through the periphery of the pulsator 6 into the washer/dehydration tub 5. Thus, the air bubbles are supplied
into the washer/dehydrator tub 5 only through the bubble outlet holes 38, whereby the bubble supply efficiency can be improved.
Next, an explanation will be given to further another embodiment of the present invention.
Although the rear vanes 29 for fining air bubbles are of a flat shape in the aforesaid embodiments, the rear vanes may be of an undulated shape as shown in Fig. 7 or of a comb shape as shown in Fig. 8.
Fig. 7 is a top view illustrating a modification of the rear vanes, and Fig. 8 is a side view illustrating another modification of the rear vanes. In Figs. 7 and 8, components corresponding to those shown in Fig. 3 are denoted by the same reference characters. As shown in Fig. 7, rear vanes 29a each have an undulated shape as seen from the top of the pulsator 6.
With this arrangement, the rear vanes 29a each have a greater surface area thereby to operate more effectively. Therefore, the rear vanes 29a can more efficiently fine the air bubbles supplied to the rear side of the pulsator 6.
As shown in Fig. 8, rear vanes 29c each have a generally comb shape with a plurality of slits 29d formed in a lower edge portion thereof as seen laterally of the pulsator. With this arrangement, the rear vanes 29c each have a greater effective surface area, thereby offering an improved bubble
fining effect.
There will next be explained a modification of the bubble outlet holes.
Although the bubble outlet holes 38 are generally uniformly distributed over the pulsator 6 as shown in Fig. 3 in the aforesaid embodiments, the bubble outlet holes may have different open areas and may be arranged at different intervals.
When the pulsator 6 is rotated, part of the washing liquid present on the rear side of the pulsator 6 flows toward the periphery of the pulsator 6. The flow speed of the washing liquid and hence the amount of air bubbles progressively increase toward the periphery of the pulsator 6. Therefore, the air bubbles supplied through the through-holes 27 and fined by the rear vanes 29 tend to be distributed heavily in the peripheral portion of the pulsator 6.
Where the bubble outlet holes 38 are uniformly provided over the pulsator 6 as in the aforesaid embodiments, the air bubbles are supplied into the washer/dehydrator tub 5 in a greater amount through the bubble outlet holes 38 located in the peripheral portion of the pulsator 6 than through the bubble outlet holes 38 located in the central portion. Therefore, the air bubbles gather in the bubble outlet holes 38 in the peripheral portion of the pulsator 6. This may prevent smooth flow of the air bubbles, failing to efficiently
supply the air bubbles.
To overcome this problem, a spacing between two radially adjacent bubble outlet holes 38a may progressively be reduced toward the periphery of the pulsator 6 to increase the distribution density of the bubble outlet holes 38a in the peripheral portion of the pulsator. That is, the total open area of the bubble outlet holes 38a present in the peripheral portion is greater than the total open area of the bubble outlet holes present in the central portion. Therefore, even if the air bubbles gather in the bubble outlet holes 38a in the peripheral portion of the pulsator 6 by the rotation of the pulsator 6, the air bubbles smoothly pass through the bubble outlet holes 38a. Thus, efficient supply of the air bubbles can be ensured.
While the embodiments of the present invention have thus been described in detail, it should be understood that these embodiments are merely illustrative of the technical principles of the present invention but not limitative of the same. The spirit and scope of the present invention are to be limited only by the appended claims.
This application claims the conventional priority benefits on the basis of Japanese Patent Applications No. 10-224484 and No. 11-118522 filed to the Japanese Patent Office on August 7, 1998 and April 26, 1999, respectively, the disclosure thereof being incorporated herein by reference.

WE CLAIM :
1 A washing machine with bubble fixing means comprising:
bubble generating means (20) for supplying air bubbles into washing liquid within a washer tub (2, 5);
bubble fining means (6, 29) for fining the air bubbles supplied into the washing liquid by the bubble generating means (20); and
a pulsator (6) provided within the washer tub (2, 5), wherein the air bubbles and water currents generated by the pulsator (6) are utilized in combination for clothes washing and rinsing operations, and wherein the pulsator (6) bubble outlet hole (38) for feeding upward within the washer tub (2, 5) the air bubbles supplied into the washing liquid by the bubble generating means (20); characterized in that
the bubble fining means (6, 29) is a vane (29) provided on an under surface of the pulsator (6).
2. A washing machine as claimed in claim 1, wherein said rear vane (29) is disposed radially of the pulsator (6) on the under surface of the pulsator (6).
3. A washing machine as claimed in claim 2, wherein said rear vane (29) is a plurality of rear vanes (29) disposed radially of the pulsator (6).
4. A washing machine as claimed in claim 1, wherein the pulsator (6) has a
plurality of compartments (37a, 37b, 37c) .__. provided on a rear
side thereof and radially separated from each other, the compartments (37a, 37b, 37c) each having the bubble outlet hole (38) in a ceiling thereof.
5. A washing machine as claimed in any of claims 1 to 4, wherein the
washer tub (2, 5) is provided with a washer/dehydrator tub (5) ,
capable of retaining water therein, an outer tub (2) of said washing tub (2, 5) has a bubble outlet (24) provided on a lower wall portion thereof for introducing the air bubbles supplied from the bubble generating means (20) into said outer tub (2), and the washer/dehydrator tub (5) has a through-hole (27) formed in a lower wall portion thereof for introducing therein the air bubbles supplied into the washing liquid.
6. A washing machine as claimed in claim 5, wherein the pulsator (6) is
rotatably provided on the bottom of the washer/dehydrator tub (5),
wherein the washer/dehydrator tub (5) has a portion (26) upwardly
recessed in the bottom thereof, the bubble outlet (24) opens adjacent the
recessed portion (26), wherein the through-hole (27) is provided in the
recessed portion (26) so that the air bubbles supplied from the bubble
outlet (24) is introducible into the washer/dehydrator tub (5).
7 A washing machine as claimed in claim 5 or 6, wherein the outer tub (2) is supported in a vibro-insulating manner by an outer frame (1), wherein the bubble generating means (20) has an air supplying means provided above a main body of the washing machine, and an air feed line (21, 23) which connects the air supplying means (20) to the bubbles outlet (24), where in the air feed line (21, 23) being divided into an upper feed line (21) and a lower feed line (23) which are connected by a connector (22) provided adjacent a side wall of the outer tub (2).
8 A washing machine as claimed in claim 7, wherein the upper feed line (21) is connected horizontally to the lower feed line (23) by the connector (22).

9. A washing machine as claimed in claim 7 or 8, wherein the upper feed line (21) is formed of a flexible material.
10. A washing machine as claimed in any of claims 7 or 9, wherein the lower feed line (23) has an inside diameter greater than that of the upper feed line (21).
11. A washing machine as claimed in any of claims 1 to 10, wherein the bubble fining means (6, 29) has sealing means (40) provided between the pulsator (6) and the washer tub (2, 5) for preventing the air bubbles supplied into the washing liquid from leaking from other portions than that bubble outlet holes (38) formed in the pulsator (6).
12 A washing machine as claimed in claim 11, wherein the sealing means consist of a labyrinth mechanism (40) which has a groove (6b) having a plurality of cylindrical walls (6a) provided on either one of an outer circumferential portion of the pulsator (6) and a bottom wall portion of the washer tub (2, 5) opposed to the outer circumferential portion of the pulsator (6), and an annular wall (5a) provided on the other in a non-contact engagement with an open portion of the groove (6b) with play.
13. A washing machine as claimed in any of claims 1 to 12, wherein the bubble outlet hole (38) provided in the pulsator (6) has a plurality of bubble outlet holes (38), wherein the total open area of bubble outlet holes (38) located in a central portion of the pulsator (6) is smaller than a total open area of bubble outlet holes (38) located in a peripheral portion of the pulsator (6).
14 A washing machine as claimed in any of claims 5 to 13, wherein the bubble outlet (24) is provided with a check-valve (24a) for preventing the washing liquid from flowing back into the air feed line (21, 23) from the outer tub (2).
15. A washing machine with bubble fixing means substantially as
hereinbefore described with reference to and as illustrated in the accompanying drawings.

Documents:

1024-del-1999-abstract.pdf

1024-DEL-1999-Claims.pdf

1024-del-1999-complete specification (as files).pdf

1024-del-1999-complete specification (granted).pdf

1024-del-1999-correspondence-others.pdf

1024-del-1999-correspondence-po.pdf

1024-DEL-1999-Description (Complete).pdf

1024-del-1999-drawings.pdf

1024-del-1999-form-1.pdf

1024-del-1999-form-19.pdf

1024-DEL-1999-Form-2.pdf

1024-del-1999-form-3.pdf

1024-del-1999-form-5.pdf

1024-del-1999-gpa.pdf

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Patent Number

199820

Indian Patent Application Number

1024/DEL/1999

PG Journal Number

08/2007

Publication Date

23-Feb-2007

Grant Date

08-Dec-2006

Date of Filing

28-Jul-1999

Name of Patentee

SANYO ELECTRIC CO., LTD.

Applicant Address

5-5, KEIHANHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.

Inventors:

#	Inventor's Name	Inventor's Address
1	YORIHISA FUNADA	C/O SANYO ELECTRIC CO., LTD.,5-5, KEIHNHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.
2	TAKAO KURASEKO	C/O SANYO ELECTRIC CO., LTD.,5-5, KEIHNHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.
3	SHIGEKIYO KAWAZOE	C/O SANYO ELECTRIC CO., LTD.,5-5, KEIHNHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.
4	HARUO MAMIYA	C/O SANYO ELECTRIC CO., LTD.,5-5, KEIHNHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.
5	YOSHIKAZU BANBA	C/O SANYO ELECTRIC CO., LTD.,5-5, KEIHNHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.
6	TSUYOSHI MURAO	C/O SANYO ELECTRIC CO., LTD.,5-5, KEIHNHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.
7	YASUSHI ARAKI	C/O SANYO ELECTRIC CO., LTD.,5-5, KEIHNHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.
8	SHIGEKI YOSHIDA	C/O SANYO ELECTRIC CO., LTD.,5-5, KEIHNHONDORI 2-CHOME, MORIGUCHI-SHI, OSAKA 570-8677, JAPAN.

PCT International Classification Number

D06F37/04

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	10-224484	1998-08-07	Japan