Title of Invention

A WASHING MACHINE

Abstract

ABSTRACT A washing machine according to the present invention includes: a tub (11) for holding water; a basket (12) provided rotatably in the tub (11) for holding fabric articles therein and having perforations; a pulsator (14) provided at the bottom of the basket (12) and having a plurality of radial top fins (30) on the top face for agitating water in the basket (12); a plurality of back fins (33) provided at the back face of the pulsator (14); and a plurality of openings (35) provided in the pulsator (14) for ejecting water upward therethrough into the basket (12). Since the openings (35) are formed in the pulsator (14) in the present invention, instead of in the basket in conventional washing machines, the water currents ejected from the openings (35) become stronger. The structure of the washing machine is simplified and the production cost is reduced.

Full Text

The present invention relates to a washing machine. BACKGROUND OF THE INVENTION The washing or rinsing performance of a washing machine is improved by generating vertical currents in the water within the basket, as well as horizontal currents caused by the pulsator. In a conventional washing machine, for example, water ejecting holes are provided at the bottom of the basket around the pulsator, and ejecting paths are formed from the space between the pulsator and the bottom plate of the basket to the water ejecting holes. When the pulsator rotates, back fins of the pulsator thrust water under the pulsator into the ejecting paths, and the water is then ejected through the water ejecting holes into the basket, whereby vertical currents are generated in the basket. Since, in the conventional washing machine, however, water ejecting holes are provided at the bottom of the basket, the structure of the basket is complicated and the production cost of the washing machine is increased. SUMMARY OF THE INVENTION An object of the present invention is, therefore, to provide a novel washing machine that can generate strong vertical currents in the water within the basket with a less complicated structure and without increasing the production cost. Accordingly, the present invention provides a washing machine comprising: a tub for holding water; a basket provided rotatably in the tub for holding fabric articles therein and having perforations; a pulsator provided at a bottom of the basket for agitating water in the basket; a plurality of radial back fins provided at a back face of the pulsator; and a plurality of openings provided in the pulsator for ejecting water upward therethrough into the basket. When the pulsator is rotated in washing or in rinsing, the back fins thrust the water under the pulsator towards the openings. Water is then ejected upward from the openings into the basket with the momentum given by the back fins, which generates strong upward currents in the water in the basket. Since the pulsator is rotating, the upward currents move violently and the fabric articles in the basket are better agitated and have a much greater chance of contacting fresh water or water with soap. The openings may be placed anywhere in the pulsator. But it is recommended that they are placed in plane portions between top tins of the pulsator if the pulsator has a plurality of radial top fins on its top face. Since the space between the pulsator and the bottom plate of the basket is narrower under such plane portions, the water pressure increases there and the momentum of the water ejected from the openings becomes stronger. Another advantage of this configuration is that it is easier to manufacture the pulsator if the openings are placed in the plane portions rather than finned portions. It is also preferable to provide a hole or holes in the bottom of the basket, and to provide the openings at a periphery of the pulsator. More water can be supplied in the space under the pulsator if the hole or holes are provided under the pulsator, and the pressure of water becomes larger at the periphery of the pulsator, which makes the momentum of the water ejected from the openings stronger. In order to obtain stronger water jets in the basket, the water under the pulsator should be effectively gathered towards the openings and turned to the upward jets. For that purpose, it is preferable to provide the openings at a periphery of the pulsator and make them smaller than the distance between neighboring back fins. The back fins guide the water under the pulsator towards the openings. A pair of auxiliary ribs that bridge the lateral ends of an opening to the neighboring back fins are effective in gathering more water to the openings. Another preferable configuration is that: a downward circumferential rib is formed along the circumference of the pulsator; the openings are placed just inside of the circumferential rib; and the height of the circumferential rib is made larger at the openings. It is further preferable to form a scoop extending inwardly from the lower part of the circumferential rib under the opening to draw more water towards the openings. The water pressure becomes larger at the openings and the water jet can be stronger if the water is prevented from escaping from the circumference of the pulsator. This can be realized by forming a circular rib standing upward from the bottom of the basket located just outside of the circumferential rib. The circular rib together with the downward circumferential rib of the pulsator produces a flow resistance to the water under the pulsator and prevents the water from escaping from other than the openings. By elongating the openings circumferentially, attachments to the fabric articles such as buttons are avoided being caught by the openings. It is also preferable to provide a plurality of radial water regulating plates that divide an opening. This ensures balanced water ejection from the whole area of the openmg. The water regulating plates may completely divide the opening or they may leave a part of the opening undivided. Since the openings are formed in the pulsator in the present invention, instead of in the basket in conventional washing machines, strong vertical currents are generated in the water of the basket. This enhances redistribution of fabric articles in the basket, and assures a constant contact between the fabric articles and fresh water or water with soap, which leads to a better washing and rinsing performance. Another advantage is that the structure of the basket is simplified and the production cost of washing machines is reduced. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a vertical cross-sectional view of a washing machine embodying the present invention. Fig. 2A is the top view of the pulsator of the washing machine and Fig. 2B is a cross-sectional view at the line A-B. Fig. 3 is an enlarged vertical cross-sectional view of a bottom part of the washing machine with the pulsator. Fig. 4 is an enlarged vertical cross-sectional view of a bottom part of another washing machine embodying the present invention. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS The first embodiment of the present invention is described with reference to Figs. 1 to 3. As shown in Fig. 1, a tub 11 is provided in a body case 10, and a basket 12 is provided in the tub 11. The tub 11 is hung by four hanging rods (not shown) at the upper part of the body case 10. The basket 12 is sustained by a vertical axle 13 at the bottom center. A pulsator 14 is provided at the top of the vertical axle 13 and at the bottom of the basket 12 for generating a water swirl in the basket 12 for washing fabric articles, and many perforations are formed in the peripheral wall of the basket 12 for extracting water from the fabric articles after washing or rinsing. At the bottom of the axle 13 is provided a clutch mechanism 15 by which two working modes are realized: a washing mode in which the pulsator 14 rotates alone while the basket 12 stays static, and an extracting mode in which the pulsator 14 and the basket 12 rotate together. On the back face of the bottom of the tub 11 is attached a motor 16. A motor pulley 17 on the shaft of the motor 16 and a main pulley 19 on the lower shaft of the clutch mechanism 15 are coupled by a V-belt 18, whereby the basket 12 and the pulsator 14 are driven either alone or together by the motor 16. A drain pipe 20 is connected at the bottom of the tub 11, and a solenoid valve 21 is provided on the drain pipe 20 to control the drain. A water supply hose 22 connected to a faucet is fixed at a top-rear part of the body case 10. A supply valve 23 is provided at the end of the water supply hose 22 to control the water supply. The water is supplied into the basket 12 through a soap box 24 in which soap is prepared before washing. As shown in Figs. 2A and 2B, five top fins 30 stand on the top face of the pulsator 14 almost equiangularly. There are plane portions 31 between the top fins 30, and each of the plane portions 31 slants slightly downward towards the center of the pulsator 14. At the central part, or at the lower part, of the plane portions 31 are formed small holes 32 for completely draining water from the basket 12. On the back face of the pulsator 14 are formed almost equiangularly ten back fins 33, and a circumferential rib 34 is formed downwardly at the circumference of the pulsator 14. A circumferentially elongated opening 35 is formed at an outer end of each plane portion 31 and at just inside of the circumferential rib 34. Five water regulating plates 36 for each opening 35 are fixed on the back face of the pulsator 14. The water regulating plates 36 extend into the opening 35 and divide a part of the opening 35, but does not reach the circumferential rib 34, leaving an undivided portion in the opening 35. A pair of auxiliary ribs 37 are provided to bridge the lateral ends of the opening 35 to the two neighboring back fins 33. The height of the circumferential rib 34 is made larger at the openings 35. The pulsator 14 is placed at the bottom of the basket 12 as shown m Fig. 3. The bottom wall 40 of the basket 12 has holes 41 for passing water between the basket 12 and the tub 11. In the bottom of the basket 12 is formed a depression having a shape corresponding to the back fins 33 of the pulsator 14, and a ckcular rib 42 stands just inside of the rim of the depression and just outside of the circumferential rib 34 of the pulsator 14. The circular rib 42 standing on the bottom of the basket 12 and the circumferential rib 34 extending downward from the pulsator 14 form a narrow corrugated path (shown by the fine arrows in Fig. 3) through which water hardly escapes from under the pulsator 14 to the above pulsator 14. When water is filled in the tub 11 and basket 12 in washing or rinsing and the pulsator 14 is rotated, water is sucked up through the holes 41 by means of the pumping effect of the back fins 33. The water then flows outward under the pulsator 14 as shown by the thick arrows. The water under the plane portions 31 flows between the back fins 33 and is converged by the auxiliary ribs 37 toward the openings 35. Part of the water thus converged flows through the above-cited narrow corrugated path, but most of the water comes up through the openings 35 because the narrow corrugated path present a greater resistance to the flow of water. The water ejected from the openings 35 has a strong momentum and causes strong upward currents in the water of the basket 12. Since the pulsator 14 rotates, water ejected from an opening 35 tends to bias toward one end of the opening 35 if there is no water regulating plates 36. But the water regulating plates 36 assure an even distribution of water ejected from the openings 35. Since the upward currents from the openings 35 move violently as the pulsator 14 rotates, the fabric articles in the basket 12 are pushed and mingled by the currents, which assures contact of every part of the fabric articles to fresh water or water with soap. The strong currents of water in the basket 12 are also effective in assisting the water to penetrate through the fabric articles, which provides better washing and rinsing performances. The shape of the opening 35 is designed circumferentially long, which prevents attachments, such as buttons, from being caught by the openings and detaching from the fabric articles. Even if such attachments as buttons fall off from the fabric articles, the water regulating plates 36 prevent them from falling under the pulsator 14. On the other hand, filaments falling off from the fabric articles flow with the currents through the openmgs 35 because there is left an open passageway between the water regulating plates 36 and the circumferential rib 34. This prevents such filaments from clogging the openings 35, and assures constant delivery of strong vertical currents in the basket 12. Another embodiment of the present invention is shown in Fig. 4, in which a scoop 38 is provided at each of the openings 35. The scoop 38 extends inwardly from the lower part of the circumferential rib 34 under the opening 35, and helps in the accumulation and distribution of more water under the pulsator 14 to the opening 35. This provides stronger currents m the basket 12 and enhances washing and rinsing performances. I WE CLAIM: 1. A washing machine comprising: a tub (11) for holding water; a basket (12) provided rotatably in the tub (11) for holding fabric articles therein and having perforations; a pulsator (14) provided at a bottom of the basket (12) for agitating water in the basket (12); a plurality of radial back fins (33) provided at a back face of the pulsator (14); and a plurality of openings (35) provided in the pulsator (14) for ejecting water upward therethrough into the basket (12). 2. The washing machine as claimed in claim 1, wherein a plurality of radial top fins (30) are provided on a top face of the pulsator (14), and the openings (35) are placed in plane portions (31) of the pulsator (14) between the top fins (30). 3. The washing machine as claimed in claim 2, wherein a hole or holes (41) are provided in the bottom of the basket (12), and the openings (35) are placed at a periphery of the pulsator (14). 4. The washing machine as claimed in claim 2, wherein the openings (35) are placed at a periphery of the pulsator (14) and the openings (35) are smaller than the distance between neighboring back fins (33). 5. The washing machine as claimed in claim 3 or 4, wherein a pair of auxiliary ribs (37) are formed to bridge the lateral ends of each of the openings (35) to the neighboring back fins (33) in order to gather and lead more water to the opening (35). 6. The washing machine as claimed in claim 4, wherein a downward circumferential rib (34) is formed along the circumference of the pulsator (14); the openings (35) are placed just inside of the circumferential rib (34); and the height of the circumferential rib (34) is made larger at the openings (35). 7. The washing machine as claimed in claim 4, wherein a scoop (38) is provided to each of the openings (35), the scoop (38) extending inwardly from the lower part of the circumferential rib (34) under the opening (35). 8. The washing machine as claimed in claim 4, wherein a downward circumferential rib (34) is formed along the circumference of the pulsator (14); the openings (35) are placed just inside of the circumferential rib (34); a circular rib (42) standing upward from the bottom of the basket (12) at just outside of the circumferential rib (34) to produce a flow resistance to the water under the pulsator (14) escaping from other than the openings (35). 9. The washing machine as claimed in claim 4, wherein the openings (35) are circumferentially elongated. 10. The washing machine as claimed in claim 9, wherein a plurality of water regulating plates (36) are provided radially on the back face of the pulsator (14) for each of the openings (35). 11. A washing machine substantially as herein described with reference to the accompanying drawings.

Documents:

0744-mas-1997 abstract-duplicate.pdf

0744-mas-1997 abstract.pdf

0744-mas-1997 claims-duplicate.pdf

0744-mas-1997 claims.pdf

0744-mas-1997 correspondence-others.pdf

0744-mas-1997 correspondence-po.pdf

0744-mas-1997 description (complete) duplicate.pdf

0744-mas-1997 description (complete).pdf

0744-mas-1997 drawings.pdf

0744-mas-1997 form-19.pdf

0744-mas-1997 form-2.pdf

0744-mas-1997 form-26.pdf

0744-mas-1997 form-4.pdf

0744-mas-1997 form-6.pdf

0744-mas-1997 others.pdf

0744-mas-1997 petition.pdf