Title of Invention

BUTTONHOLE STITCHING MACHINE

Abstract

I Claim. A buttonhole stitching machine comprising - Power drive motor with a transmission means provided with belt pulley gear box at one side of the main frame and connected directly to the main shaft of the machine so as to provide stitching action by the stitching means provided at the other end of the machine frame, - a timer and lock means being provided near a driven wheel attached to the said belt pulley so as to lock the movement of the driven wheel upon completion of each buttonhole stitching, - a cutter assembly connected to said timer and lock being provided to cut the buttonhole in the centre of the stitched buttonhole. - said power drive motor with transmission means having gear box assembly to reduce the stitching speed of the machine. - steering means supported on the main shaft of the gear box assembly being provided for steering the movement of the needle, locking means including a grooved wheel attached to a periphery lock being provided near the driven wheel to lock the movement of driven wheel, after completion of one cycle of rotation, a start lever being provided near the bottom of the main frame for starting the machine by unloading the locking mechanism, a pressure foot being provided at the stitching end of the machine to keep the work piece in position, a counter being provided on the side of the driven wheel so as to count the number of stitched buttonhole and lighting means being provided near the needle assembly for facilitating the stitching functions even in the absence of sufficient light. - a cam follower assembly being provided on the output shaft of gear box to provide desired width of the buttonhole - a protruded wheel attached to the pressure plate through a set of linkages at the end of the said output shaft of the gearbox for providing longitudinal stitching of the buttonhole. - a bevel gear mounted on the main shaft transmits rotational movement parallely to another shaft placed at the bottom of main frame through perpendicularly positioned gear-shaft assembly. A set of helical gear and bobbin set attached to the end of the said bottom shaft for operating said cutter assembly to cut thread upon completion of the buttonhole stitching.

Full Text

FORM 2 THE PATENTS ACT 1970 COMPLETE SPECIFICATION (SECTION 10) TITLE fx BUTTONHOLE STITCHING MACHINE 0 Applicant Anil Rashmikant Kamdar, Q h ~L~O' h ' z eLr . ., Khadi Faliya, Near Santoshi Mata Temple, Godhra, Gujarat, INDIA The following specification partially describes the nature of the invention and the manner in which it is to be perforrne4.. 11 0 DEC 2003 L Z O - / o - & O q - - Field of the Invention This invention relates to a buttonhole sewing machine for preparing buttonholes on a work piece of fabric. Description of Prior Art The stitching of a buttonhole is one of the most demanding and difficult sewing tasks to perform with complete success. However a buttonhole apparatus is available in the market and is adapted to be attached with a conventional sewing machine, primarily consisting of a body having a slot for the pressure bar, niddle assembly, bobbin set . A fork arm lever, a presser foot, a special needle setting screw, setting screw on the cover plate, zigzag width adjusting screws, buttonhole width adjusting screw and buttonhole length adjusting screws are provided with the apparatus to facilitate the operation of the sewing machine. To fit the buttonhole apparatus with the sewing machine, the presser foot and the needle clamp screw are removed from the sewing machine. The special needle setting screw is used to set the needle. The cover plate is placed on top of the needle plate in such a way that the needle falls right through the center of the cover plate slot. Further, the hand-wheel is turned to bring the needle to its highest position and the buttonhole apparatus is placed from the rear so that the presser bar fits into the slot for presser bar. If the sewing machine is equipped with a drop feed mechanism, then it must be ensured that the feed dog or drop feed is placed below the needle plate. A buttonhole sewing machine is disclosed in the US patent no.5125349 and comprises a selection switch for the selection as to whether the hole is to cut first or the button hole is to be defined first. In both the cases, stitch width remains the same. Further the machine has a startlstop switch as provided in the ordinary machines. Also a needle position sensor and an offset selection input device are provided to control and easy operation of i the machine. * Another buttonhole machine is disclosed in the US patent no.4458612 and comprises a. right and left parallel side stitching parts, and another stitching part connected to the side stitching part. A switch is provided for detecting front and rear ends of each side stitching 2 . part, and is capable of sewing the buttonhole in divided parts on opposite sides of a longitudinal centerline thereof so that the two sides stitching parts are stitched in the same work feeding direction. The machine also comprises a control circuit generating a feed change signal when the number of stitches being formed in one of the side stitching parts has become equal the total number stitches of the other side stitching part less a predetermined number, and a feed adjusting circuit for reducing a work feeding increment for a time interval between generation of the change signal and a signal from the switch, to avoid a difference in the length between the side stitching parts. US patent no.6223664 B1 teaches regarding another kind of the buttonhole stitching machine comprising a swing mechanism and feed bracket are controlled to form a buttonhole defined by settings, such as zigzag stitch length, zigzag pitch, bar-tack length, bar-tack pitch, and cutter space. The buttonhole can be set on the operation panel and changed to various shapes by changing the above settings. In particular the left and right zigzag stitch widths can be set differently, and the fiont and rear bar- tack length can be also set differently. Thus, the balance of the buttonhole can be finally adjusted. Disadvantages associated with the prior art There are disadvantages associated with the prior art. One of the main disadvantages is that the conventional buttonhole apparatus having more, wear and tear. Another disadvantage is that pressure foot plate is worn out and therefore button holes are not stitched in a perfect manner after the regular use of the machine. The machine is not repairable due to non availability of the spare parts and thus it becomes useless after some time of use. Yet another disadvantage is that the whole assembly including base plate and pressure foot move during the stitching of the buttonhole and thus the maximum load is carried on . by the motor during the stitching operation of the machine. Still another disadvantage is that the conventional machines are heavy and whole machine is to be lifted even for the minor repair. A further disadvantage is that a plurality of belts is required to reduce the speed of the machine for stitching the button holes. Another disadvantage is that a clutch is needed for changing over the gear box so as to reduce or increase the speed of the machine. Yet another disadvantage is that the maintenance of these machines is very costly as the spare parts are not available in the domestic market and are to be imported. Objects and Advantages of the Invention Therefore the main object of the present invention is to propose a novel buttonhole stitching machine which obviates the disadvantages associated with the prior art. Another object is to propose a novel machine which is very simple in construction and is complete in all respect and it is not required to mount the conventional buttonhole apparatus at all. Yet another object is to propose a novel machine which is simple in construction, compact in size , having modular configuration clutch is not required to operate the machine. Still another object is to propose a novel machine, the maintenance thereof is very easy. Also the cost of the machine is very low than the imported machine. A further object of the present invention is to propose a novel machine wherein a plurality of the belts is not required to reduce the speed of the machine for stitching the button hole. Yet another object of the invention is to propose a machine wherein only pressure foot moves during the stitching operation of the machine. Also the needle changes its direction from one side to other in order to complete the stitching of the buttonhole on both the side and thus the load on the machine has been reduced substantially. Statement of the Invention The object of the invention relates to a buttonhole stitching machine comprising : - power drive motor with a transmission means provided with belt pulley gear box at one side of the main frame and connected directly to the main shaft of the machine so as to provide stitching action by the stitching means provided at the other end of the machine fiame, - a timer and lock means being provided near a driven wheel attached to the said belt pulley so as to lock the movement of the driven wheel upon completion of each buttonhole stitching, - a cutter assembly connected to said timer and lock being provided to cut the buttonhole in the centre of the stitched buttonhole. - said power drive motor with transmission means having gear box assembly to reduce the stitching speed of the machine. - steering means supported on the main shaft of the gear box assembly being provided for steering the movement of the needle, locking means including a grooved wheel attached to a periphery lock being provided near the driven wheel to lock the movement of driven wheel, after completion of one cycle of rotation, a start lever being provided near the bottom of the main fiame for starting the machine by unloading the locking mechanism, a pressure foot being provided at the stitching end of the machine to keep the work piece in position, a counter being provided on the side of the driven wheel so as to count the number of stitched buttonhole and lighting means being provided near the needle assembly for facilitating the stitching functions even in the absence of sufficient light. - a cam follower assembly being provided on the output shaft of gear box to provide desired width of the buttonhole - a protruded wheel attached to the pressure plate through a set of linkages at the end of the said output shaft of the gearbox for providing longitudinal stitching of the buttonhole. - a bevel gear mounted on the main shaft transmits rotational movement parallely to another shaft placed at the bottom of main Erame through perpendicularly positioned gear-shaft assembly. A set of helical gear and bobbin set attached to the end of the said bottom shaft for operating said cutter assembly to cut thread upon completion of the buttonhole stitching. According to this invention there is provided a buttonhole stitching machine comprising a power drive assembly provided at one side of the main fiame and connected directly to the driven wheel of the machine so as to provide stitching action by the stitching means provided at the other end of the machine frame, a timer and lock assembly being provided near said driven wheel so as to lock the movement of the driven wheel upon completion of the buttonhole stitching, a cutter assembly connected to said timer and lock assembly being provided to cut the buttonhole in the centre of the stitched buttonhole, a gear assembly being provided on the back side of the said machine such that to reduce the stitching speed of the machine for stitching the buttonhole properly, steering means supported on the main shaft of the gear box assembly being provided for steering the movement of the needle, locking means being provided near the driven wheel such that to lock the movement of driven wheel, a start lever being provided near the bottom of the main fiarne for starting the machine by unloading the locking mechanism, a pressure foot being provided at the stitching end of the machine to keep the work piece in position, a counter being provided on the side of the driven wheel so as to count the number of stitched buttonhole and lighting means being provided near the needle assembly for facilitating the stitching functions even in the absence of sufficient light. Brief Description of Accompanying Drawings In accordance with this invention the buttonhole stitching machine has power drive unit . provided at one side of the main fiame and is connected directly to the driven wheel of the machine without the help of a clutch mechanism. A timer and a timer lock unit are provided towards the driving wheel for starting the machine and actuating the cutter for cutting the threads after stitching the button hole. There is a gear mechanism provided with the machine for changing the pattern of the stitch easily. A start lever is provided near the bottom of the main frame to start the machine for the stitching of the next button hole. A pressure foot is provided at the stitching end of the machine for keeping the clothlwork piece in the position. A lever is provided to lift the pressure foot as and when required by the user. On pressing the start lever, the Timer lock or the clutch lock opens and the machine starts. The clutch mechanism is used to bring the stitch back to the place from where the stitching was left in the case of breakage of thread. The gear mechanism is used for controlling the length of the stitch and also operates the pressure foot. A counter is provided to keep a count of the number of buttonholes that are stitched. A cutting mechanism or a pressure bar is attached to the timer lock system as mentioned herein above for cutting the button hole as and when the stitching of the button hole is complete. The machine is designed in modular configuration to avoid lifting of the machine every time for the repairing purposes. This machine is free fi-om any complicated gear mechanisms for transmission of power from the power drive unit to the machine. The length of the hole can be adjusted easily in this machine compared to conventional buttonhole machines available in the market. This machine can complete three operations automatically namely stitching, cutting and stopping or locking operation effectively. A small lamp is placed near to the needle for easy working in darkness, less light or during night hours. This also helps in easy insertion of the thread in the needle. The gear mechanism is responsible for controlling the length of the stitch and also operates the pressure foot. During the operation of this machine, the cloth is placed under the Pressure foot. The switch is turned on and the starting lever is pressed. The machine completes the buttonhole stitching and cutting simultaneously. Detailed Description of Accompanying Drawings The buttonhole machine according to a preferred embodiment is herein described and illustrated in the accompanying drawings wherein; Fig. 1 - shows the front elevational view of the machine, Fig. 2 - shows the arrangement of the driving unit with the main shaft of the machine, Fig. 3(a&b) - shows front and side view of the machine having timer and locking mechanism, Fig. 4(a&b) - shows the means provided for the unloading of the locking mechanism, Fig. 5 - shows the gear box provided at back side of the machine, Fig. 6 - shows the means used for zigzag motion of the needle, Fig. 7(a&b) - shows the steering means for the needle, Fig. 8 - shows the means provided for moving the job for stitching the buttonhole, Fig. 9 - shows the cutter means for cutting the button hole, Fig. 10 - shows the automatic thread cutting means, and Fig. 11 - shows the means provided for counting the buttonhole Reference to the drawings particularly Fig. 1 the buttonhole stitching machine of the present invention has a prime maver for eg. An electric motor (1) mounted on the frame (3) supported on to the main frame (7) of the sewing table. The prime mover (1) is connected with the main pulley (8) of the machine through a conveyor belt (2). A pressure pedal (4), start pedal (5) and a clutch pedal (6) are mounted on a pivot rod (9) movebly. A spring loaded pressure clamp (12) is provided below the stitching means for holding the job in place for stitching the buttonhole. The stop locking means (17) comprises an actuating rod (16) and a timer pin (1 8) provided for controlling one cycle of the buttonhole machine. A gear box (11) having the gear train disposed therein is provided on the back side of the machine for controlling the motion of the timer plate (15). A four bar cutter linkage (10) is provided to be actuated by the actuating rod (16) and cam (13) fitted on to the pulley cap (14). Pressure pedal (4) is used for lifting the pressure clamp (12) for removing the cloth or inserting the cloth the new cloth after completing the stitching of all the required buttonholes in the cloth. Pressure pedal (4) is also used for lifting the pressure clamp (12) for displacing the cloth for stitching the next buttonhole during the process of the stitching of buttonhole. The start pedal (5) is provided to start the machine by transferring the belt to the pulley provided on the main shaft (21) of the machine (see Fig, 3) and by unloading the locking mechanism (17). The cutter linkage (10) is actuated when the primer plate (15) completes one revolution. Till the timer pin (18) moves on the surface of the timer plate (15), the locking mechanism (17) remains unloaded. The timer plate has been designed in such a way that as soon as the last stitch is complete, the timer pin (1 8) locks the timer plate (15), and thus locking mechanism and the movement of the actuating means (16) along the cam (13) causes the movement of the rocker arm of the cutter linkage (10) leading to the blade cutting action. Main pulley (8) of the motor (1) is connected to the main shaft (21) through the pulleys (19) and (20) provided on one end of the main shaft (21). Pulley (19) is a free pulley and pulley (20) is fixed to the main shaft (21). A pairs of bush (59) and (64) are provided at both the ends of the outer body of the machine such that to support said main shaft (21) rotatebly. The rotary motion of the main shaft (21) is transferred to other means/mechanisms with the help of the bevel gears (60) & (63), worm gear (31) and worm wheel (32) mounted thereon. A crank (65) is provided at the other end of the main . shaft (21) for providing the jumping motion to the needle as well as to the means provided for releasing the thread. The driving motor (1) rotates the free pulley (19) mounted on the main shaft (21) through the round belt (2) and on pressing the start lever (5), the belt is shifted to the driving pulley (20) which drives the main shaft (21) and thus the bevel gear (60), worm (3 1) and bevel gear (63) rotate. The bevel gear (60) transmits the rotary motion from the main shaft (21) to the shuttle mechanism through another bevel gear (61). The worm (31) transmits the rotary motion to the worm wheel (32), which transmits the rotary motion to timer and needle steering mechanisms through the gearbox. The bevel gear (63), transmits the rotary motion to an arm through another bevel gear (62) for providing zigzag movement to the needle. As shown Fig. 3, A timer (1 5) and locking mechanism (1 7) are provided on the same side of the machine where the driving pulleys (20) & (19) are provided. The belt-changing lever (22) is attached to the locking mechanism (17), which is pivoted at the pivot (23) through a link (53) attached to the main body. The force is applied at the point (24) compressing the high stiffness spring (25). The actuating rod (16) is connected to the rod (26) and rests over the spring (28). The spring is attached to the surface of a screw (27) that passes through the nut (29). There is another bolt (30) attached to the frame (17) and the pivot rod (48) is extended to which the link (50) of the unloading mechanism is temporarily attached. The belt (2) is attached to the free pulley (19) when the machine is idling. On pressing the start pedal (5), the clutch wire attached to arm (24) is pulled, thereby causing the whole locking mechanism pivoted about pivot (23) to unload and unlocking the pulley cam (1 3) and timer (10). The restoring force is provided by the spring (25), which compresses when, the mechanism (17) is unloaded. The locking mechanism gets unloadkd thereby shifting the belt fiom free pulley (1 9) to keyed pulley (20) through the movement of belt changing lever (22). This causes motion of the main shaft (21) that drives all other parts of the machine, until the timer (15) completes one rotation and gets locked again. Once the mechanism gets unloaded and belt gets engaged, it remains so till the completion of one revolution of the timer (1 5) since the timer pin (1 8) rests against its surface. When the last stitch is completed, the actuating pin (16) moves along the surface of the cam (13). During this movement, the rod (26) also moves along with it and the spring (28) gets compressed thereby providing the restoring force. Movement of the rod (26) causes the movement of the four bar linkage cutter mechanism (10) and thus causing the blade cutting action. The height of the pin (16) and thus the span of the blade can be adjusted with a screw (27) that controls the length and tension in the spring. Reference is now made to Fig 4 which shows the unloading of locking mechanism (17) that is helpful in troubleshooting faults in the machine while the machine is in running condition. It comprises of two links (51) and link (50) is attached to the locking mechanism (17) in the loaded position. The link (51) is attached to the main body of the machine on one end and to link (50) on the other. It consists of a slot (52) in the middle, which causes the unloading of the machine. When the locking mechanism (17) is to be unloaded and the link (50) is removed from . the nut (49) and the start pedal is pushed. On pressing the start pedal, the clutch arm (24) is pulled and the mechanism moves about the pivot (23) and comes to the position I1 as shown in the figure. Then the bolt (30) gets fitted into the slot (52) in the link (51). The position of the slot is such that, the mechanism remains there as long as the link (51) is not removed from the bolt (30) and the machine keeps on moving irrespective of completing the buttonhole. The figure 5 shows the gearbox (1 1) arrangement for timer (1 5) in the machine. The drive from the motor is supplied to the main shaft (21), which contains a worn (31), which is ' meshed with a worm wheel (32) fitted on shaft (37). The shaft (37) also contains a spur gear (33), which acts as a pinion to spur gear (39, which is fitted on a small shaft (38) parallel to shaft (37). The spur gear (35) transfers its motion to a bevel gear (36) through a collar that moves freely on a fixed shaft (38). Another bevel gear (43) is attached to the shaft (37) that can be meshed with the gear (40) fitted on the shaft (34). Depending upon the number of stitches to be made in the buttonhole, one of the bevel gears (39) or (40) on shaff(34) is meshed with one of the two bevel gears (36) and (43) perpendicular to the shaft (34). The reduction at this level decides the angular speed of the shaft (34) and thus the timer (15). The adjuster lever (41) connected to the shaft before the steering wheel (45), which works through a needle driver (44) that rests on it and moves along the profile in the slot (48). At the end, the shaft contains a needle translator mechanism (46), which causes the movement of the presser foot assembly. The adjuster lever (41) moves on the surface of thin disc (42), which has teeth on its surface and is attached to the shaft (34). Teeth are made in such a way that the clockwise movement of the adjuster (41) produces motion of the disc (42) and thus the shaft (34) in the same direction while the anti-clockwise movement does not produce any motion. This adjuster (41) produces motion of the disc (42) and thus the shaft (34) in the same direction while anticlockwise movement does not produce any motion. This adjuster (41) is used to adjust the position of the needle back to the point where it was stopped in between due to any reason such as thread breakage, needle breakage etc. The steering mechanism guides the needle along the width of the buttonhole. The needle steering (45) is made such that the driver (44) rests on a slot made on it. Two semi-circular slots (48) are made that are offset from the center and joined at ends through a transition path. When the driver moves on the steering, it remains at the same X-coordinate as long as it is in the same semi-circle. On going through the transition slot (48), it moves along the X-axis and then on reaching the next semi-circular slot, it again gets fixed. Thus the shape of the slot guides the driver (44) to cause a corresponding motion in the connecting rod (49) that connects the driver to the needle holder cover. Like the needle steering that causes the displacement of the needle from one side to other side of the buttonhole, the needle translator (46) causes the 11 presser clamp to move with the work piece along with the length and thereby forming the shape of a buttonhole. The needle translator (46) consisting of a crank is connected to the main firame containing the presser footlclamp by a link (47), which causes the translation motion of mainframe along the length of buttonhole. As shown in Fig 6 the zigzag motion mechanism for the needle has a bevel gear (62) . which is driven by bevel gear (63) secured with the main shaft (21). Gear (62) is disposed in and U shaped cavity provided at one end of the arm (66). The arm (66) is designed in a specific/peculiar shape such that to be fitted with the design of the outer body of the machine. A rectangular pin (68) is attached to the arm for providing support thereto. There is an adjuster (67) provided on the sides of rectangular pin (68) for controlling the motion of the arm (66). The arm (66) is connected to the needle holder cover (70) at the lower end thereof through a revolute joint (69). The needle holder cover (70) has a needle holder (71) in which needle (72) is inserted. When the gear (62) is in motion, the arm (66) rocks in its plane according to the place adjusted by the adjuster (67). When the adjuster (67) is in the present orientation, the arm rocks in the Y- direction only since the pin (68) can move in that direction. The revolute joint (69) thus ensures no movement of the needle holder cover (70) in that direction. In this orientation, thus there is no zigzag movement. If the adjuster (67) is in orientation 90 degrees to present, it allows the movement only along X-axis, which causes the maximum zigzag movement of the needle holder (58). Thus we can have a large range for width of zigzag stitch. Reference is now made to Fig, 7, wherein the steering mechanism has been shown. The profile of the slot in steering (45) causes the movement of the driver (44) along the Xaxis. The driver (44) is connected to the link (74) through a revolute joint (73). The link (74) is then connected to the link (75) through another such joint, which goes into the guide (76), which is pivoted at the point (77) to the main body. Between the pivot and the guide is the adjustment knob (67), which extends and is attached to the needle holder cover (70). When the steering wheel (45) rotates, it causes the rocking motion of the driver (44) that is converted into twisting motion of the link (74) through the joint (73). Thus through a similar joint, this twisting motion is converted into rocking motion of the link (75) that has an adjustable length. The link (75) moves inside the guide part of the link (76), which then oscillates about the pivot point (77). The amplitude of oscillation of the link (76) causes the movement of the (66) along with it and thus results in the shifting of the needle holder cover (70). Thus the motion of the driver (44) on the steering wheel (45) is converted into the movement of needle from one side to the other side of the buttonhole through the innovative linkage mechanism. The transmission mechanism for the movement of presser work clamp (86) is shown in Fig 8. The transmission mechanism has been provided for causing the cloth to move along the length of buttonhole. In the Fig. the automatic thread cutter mechanism (92) ' and the mechanism for lifting the presser clamp (86) is also shown for feeding the material for making buttonholes. The needle translator (46) is attached to a frame (79) through a link (47), which is offset from the center of translator. This link is attached to the translator at point (78) and to the frame at point (80). Frame (71) is pivoted about the pivot (93) that is fixed to the sewing machine body. A link (81) and the work clamp (86) through a prismatic joint (89). The presser rod (82) is joined to the presser block (81) and thus has a spring (83) on the top, which is compressed by a nut (84) and stores an initial restoring force that presses the clamp (86). When the needle translatorlcrank (46) rotates, it causes rocking motion for the frame (79) through the link (47). This rocking leads to movement of the link (81) along the prismatic joint (89) thus causing the movement of presser clamp (86) and the automatic thread cutter (92) along the length of the buttonhole. The presence of the prismatic joint (89) ensures that the presser block (81) and the rod (82) remain fixed during this translation. On the other hand, the presser pedal . of the machine is attached to the point (95), which causes the movement of the link (81) about pivot (94) and thus the lifting of presser clamp (86). Lifting of the clamp causes compression in the spring, thereby generating a restoring force that presses the material. The nut (84) above the spring (83) is used to adjust the length of the spring (83) and thus the pressure of gripping the material. The automatic cutter mechanism is fixed to the presser clamp (86) at the bottom of the block where the cutter blade (97) is also present. When the presser clamp (86) moves along the translator, the cutter rod (91) also moves along with it. However the link (90) at the joint (89) remains fixed. Thus, when the block (87) reaches beyond the end of the link (90), it gets locked and is then compressed on Mher movement. So when the complete process is finished, the spring (88) is completely compressed. The sudden movement of the link (90) releases the block (87) and the spring (88) and thus causes the cutter blade (97) to cut the thread. As shown in Fig 9, four-bar linkage cutter means has a main frame (17) having a rod (26) provided therewith and adapted to move in the slot provided in the link (98). Link (98) is pivoted about the point (101) and joined to the link (99) at the joint (102). Link (99) is further connected to the link (100) at the joint (1 03) and is pivoted about the point (104). Link (100) acts as an actuator for the cutter (108). The cutter (108) moves over a cutter bar (105), which is fixed at both the ends to the main body; through a link (107) at the bottom. Blade (109) is present at the end of the cutter (108). The downward motion of the rod (26) causes the upward movement of link (99) that moves the link (100) about the pivot (104) and which pushes the cutter downwards. The cutter thus moves along the cutter rod (105) and compresses the spring (106) that causes it to bounce back when the link (104) returns after its maximum amplitude. Thus cutting of material takes place. The automatic thread cutting mechanisms as shown in Fig 10 is provided on both the sides of the base plate (1 10). The movement of presser clamp (86) causes the movement of the block (96) in the Z-direction. When it moves behind the link (90), it gets stuck in its position and the returning of clamp (86) to initial position causes the compression in the spring and backward movement of the link (91). The backward movement of the link (91) causes the link (1 12) to move and thus the link (1 13) to rotate. This rotation causes the blade (97) to come in the open position. When the link (90) is pulled upwards, the spring is released and link (91) moves back to its original position, thereby causing the blade to close and cut the thread in this process. The cutter below the base plate has one end (1 14) fixed to the main body of the machine. Link (1 15) is joined by a revolute joint to the curved link (1 16), which in turn is joined to the blade (1 17) through a pin (1 18). When link (1 15) is pressed downwards, the curved link causes the forward movement of the blade and thus cutting the thread from below in the process. As shown in Fig 11, the buttonhole counter linkage and the thread loosening means comprises a frame (1 7) connected to a link (120) through a curved link (1 19). Link (120) moves along a prismatic joint (121). Another branch link (122) of the linkage causes the loosening of thread in the thread guide (126). A spring (123) joins the counter lever (124) to the center of link (120). The backwardforward movement of this lever once causes the ' counter to go up by one. The unloading of frame (17) causes the links to move backwards, thereby causing the branch link (122) to withdraw from the thread guide (126). In this process, the counter lever attached to the spring also moves back. After the completion of the buttonhole, when the frame (17) comes back to its initial position, the complete linkage moves forward. This causes the branch link (122) to loosen the thread guide (126) by widening the gap between the two spheres (127) & (128). The spring (123) exerts force on the counter lever (124) and thus causes it to move forward, thereby increasing the buttonhole count by one. 1. A buttonhole stitching machine comprising - Power drive motor with a transmission means provided with belt pulley gear box at one side of the main frame and connected directly to the main shaft of the machine so as to provide stitching action by the stitching means provided at the other end of the machine frame, - a timer and lock means being provided near a driven wheel attached to the said belt pulley so as to lock the movement of the driven wheel upon . completion of each buttonhole stitching, - a cutter assembly connected to said timer and lock being provided to cut the buttonhole in the centre of the stitched buttonhole. - said power drive motor with transmission means having gear box assembly to reduce the stitching speed of the machine. - steering means supported on the main shaft of the gear box assembly being provided for steering the movement of the needle, locking means including a grooved wheel attached to a periphery lock being provided near the driven wheel to lock the movement of driven wheel, after completion of one cycle of rotation, a start lever being provided near the bottom of the main frame for starting the machine by unloading the locking mechanism, a pressure foot being provided at the stitching end of the machine to keep the work piece in position, a counter being provided . on the side of the driven wheel so as to count the number of stitched buttonhole and lighting means being provided near the needle assembly for facilitating the stitching functions even in the absence of sufficient light. - a cam follower assembly being provided on the output shaft of gear box to provide desired width of the buttonhole - a protruded wheel attached to the pressure plate through a set of linkages at the end of the said output shaft of the gearbox for providing longitudinal stitching of the buttonhole. - a bevel gear mounted on the main shaft transmits rotational movement parallely to another shaft placed at the bottom of main frame through perpendicularly positioned gear-shaft assembly. A set of helical gear and bobbin set attached to the end of the said bottom shaft for operating said cutter assembly to cut thread upon completion of the buttonhole stitching. 2. A buttonhole machine as claimed in claim 1 wherein said timer and lock means comprises a cam secured at the main shaft of the driven pulley of the machine, a spring loaded actuating rod supported on a support fiame being provided to lock the movement of said cam, a timer pin supported on the horizontal arm of said support frame being provided to bring the actuating rod in the locking position upon completion of the rotation of the timer wheel, said timer pin is disengaged from the timer wheel upon pressing the start lever to start the machine. 3. A buttonhole machine as claimed in claims 1 and 2 wherein said cutter assembly has a linkage means adapted to be connected with said spring loaded actuating rod to cut the buttonhole by a cutter provided at the other end thereof with the help of the cutter holding means simultaneously with the locking action of the driven wheel. 4. A buttonhole machine as claimed in claim 1 wherein said gear assembly comprises bevel gears secured on the respective parallel shafts being provided at right angle with the main shaft having bevel gear mounted thereon such that to transmit the rotational movement of the driven wheel to the needle and other related means at the desired speed. 5. A buttonhole machine as claimed in claims 1 and 4 wherein said steering means comprises a cam and follower assembly having a slot at the periphery thereof to accommodate a needle driver therein such that to transmit the movement of the needle along the width of the buttonhole for stitching purposes, connecting means are provided to connect the needle driver with the needle holder. 6. A buttonhole machine as claimed in claim 1 wherein said locking means comprises a horizontal link adapted to be secured with the main body of the machine, another link being provided at the other end of the said first link such that to be fitted in locking pin provided on the locking mechanism, slots are provided at the free ends of said first and second links, another link is provided between said links. 7. A buttonhole machine as claimed in claim 2 wherein a slot is provided in said said lock for accommodating the actuating rod therein during the non-stitching position of the machine. 8. A buttonhole machine as claimed in claim 2 wherein said timer wheel has a slot to accommodate the locking pin during the locking condition of the machine. 9. A buttonhole machine as claimed in claim 4 wherein a worm wheel and worn gear mounted on the said main shaft for reducing the speed of the buttonhole stitching machine. 10. A buttonhole machine substantially as herein described and illustrated in the accompanying drawings. Dated this 9th day of December, 2003 a Jaya Bhatnagar Of Anand And Anand, Advocates Attorney for the applicants

Documents:

1261-mum-2003-cancelled pages(20-10-2005).pdf

1261-mum-2003-claims(10-12-2003).pdf

1261-mum-2003-claims(granted)-(20-10-2005).doc

1261-mum-2003-claims(granted)-(20-10-2005).pdf

1261-mum-2003-claims(granted)-(6-6-2007).pdf

1261-mum-2003-correspondence(20-10-2005).pdf

1261-mum-2003-correspondence(ipo)-(23-7-2007).pdf

1261-mum-2003-correspondence(ipo)-(30-04-2007).pdf

1261-mum-2003-description(complete)-(10-12-2003).pdf

1261-mum-2003-description(granted)-(6-6-2007).pdf

1261-mum-2003-drawing(10-12-2003).pdf

1261-mum-2003-drawing(20-10-2005).pdf

1261-mum-2003-drawing(amended)-(20-10-2005).pdf

1261-mum-2003-drawing(granted)-(6-6-2007).pdf

1261-mum-2003-form 1(10-12-2003).pdf

1261-mum-2003-form 19(31-08-2004).pdf

1261-mum-2003-form 2(10-12-2003).pdf

1261-mum-2003-form 2(granted)-(20-10-2005).doc

1261-mum-2003-form 2(granted)-(20-10-2005).pdf

1261-mum-2003-form 2(granted)-(6-6-2007).pdf

1261-mum-2003-form 2(title page)-(10-12-2003).pdf

1261-mum-2003-form 2(title page)-(granted)-(6-6-2007).pdf

1261-mum-2003-form 3(10-12-2003).pdf

1261-mum-2003-power of authority(10-12-2003).pdf

1261-mum-2003-specification(amended)-(20-10-2005).pdf

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