Cloth cutter driving device of differential feeding sewing machine

Abstract

The utility model provides a cloth cutter driving device of a differential feeding sewing machine, and belongs to the technical field of machinery. The problem that installation of a cloth cutter driving device of an existing differential feeding sewing machine occupies the side space of a shell is solved. The cloth cutter driving device of the differential feeding sewing machine comprises a cloth cutter connecting rod, an eccentric wheel, a cutter bar and a cutter bar connector, the eccentric wheel is provided with a mounting hole allowing an upper shaft to penetrate through, the two sides of the eccentric wheel are provided with a first eccentric part and a second eccentric part respectively, and the first eccentric part and the second eccentric part are eccentrically arranged relative to the mounting hole; a sliding rail is fixed in the machine shell, one end of the cutter bar connector is fixed on the cutter bar, the other end of the cutter bar connector is slidably connected with the sliding rail through a sliding block, the cloth cutter connecting rod is sleeved in the middle of the cutter bar connector, and the lower portion of the cutter bar extends below the machine shell to be connected with the cloth cutter assembly and can drive the cloth cutter assembly to move up and down. According to the cloth cutter driving device of the differential feeding sewing machine, the cloth cutter driving device is arranged in the machine shell and below the front end of the machine shell, so that the side space of the machine shell is prevented from being occupied.

Description

Technical Field

[0001] The utility model belongs to the technical field of machinery, and relates to a differential feeding sewing machine, in particular to a cloth cutting knife driving device of the differential feeding sewing machine. Background Art

[0002] A differential feed sewing machine is designed for flat seams and flat edges. It can be used to sew a variety of fabrics, especially multi-layered and thick fabrics. The differential feed system of an existing differential sewing machine consists of an upper shaft, a differential feed shaft, and a swing seat, enabling adjustment of the differential feed speed.

[0003] In actual use, a differential feed sewing machine also has the function of using a cloth cutting knife to simultaneously cut cloth during the sewing process. The existing cloth cutting knife drive device can be installed on the casing as an independent module, or it can be driven by installing components of the drive device on the side of the casing to drive the cloth cutting knife up and down to cut the cloth. For example, Chinese patent [Application No. 202221720868.5; Publication No. CN217499639U] discloses a differential lockstitch sewing machine cutter installation structure, which includes a housing, an upper shaft, a cutter assembly, a connecting rod assembly, and a wrench assembly; the back side of the housing is provided with a notch, the notch extending outward to form a protective cover, and the wrench assembly includes a wrench shaft and a wrench, the wrench shaft is at least partially disposed within the protective cover, and the wrench is disposed at the end of the wrench shaft.

[0004] The above-mentioned differential lockstitch sewing machine cutter mounting structure has a notch on the back of the housing and a protective cover, creating a space for mounting the cutter drive device on the side of the housing, thereby achieving cutter installation. However, this cutter mounting structure adds a protruding portion to the side of the housing, which occupies space on the side of the housing. Summary of the Invention

[0005] The purpose of the utility model is to address the above-mentioned problems in the existing technology and propose a cloth cutting knife driving device for a differential feeding sewing machine. The technical problem solved by the utility model is how to achieve a reasonable layout of the installation of the cloth cutting knife driving device.

[0006] The object of the utility model can be achieved through the following technical solutions: a cloth cutting knife driving device of a differential feeding sewing machine, the differential feeding sewing machine includes a casing, a presser foot, a needle bar and a cloth cutting knife assembly, the upper shaft is installed in the casing, the front end of the upper shaft is installed with an eccentric connecting rod for driving the presser foot, and the cloth cutting knife driving device is characterized in that the cloth cutting knife driving device includes a cloth cutting knife connecting rod and an eccentric wheel, the eccentric wheel has a mounting hole for the upper shaft to pass through, the two sides of the eccentric wheel respectively have an eccentric part 1 for mounting the eccentric connecting rod and an eccentric part 2 for mounting the cloth cutting knife connecting rod, the eccentric part 1 and the eccentric part 2 are eccentrically arranged relative to the mounting hole; the cloth cutting knife driving device also includes a knife rod and a knife rod joint, a slide rail is fixed in the casing, one end of the knife rod joint is fixed on the knife rod, and the other end is slidably connected to the slide rail through a slider, the cloth cutting knife connecting rod is sleeved in the middle of the knife rod joint, the lower part of the knife rod extends to the bottom of the casing and is connected to the cloth cutting knife assembly and can drive the cloth cutting knife assembly to move up and down.

[0007] The cloth-cutting knife drive device of this differential-feed sewing machine utilizes an eccentric wheel having eccentric portions 1 and 2, enabling the upper shaft to rotate and drive the eccentric connecting rod to drive the presser foot, thereby simultaneously driving the cloth-cutting knife connecting rod to swing. A slider connected to the knife bar joint can slide up and down along a slide rail, converting the swinging motion of the cloth-cutting knife connecting rod into up and down motion of the knife bar, thereby driving the cloth-cutting knife assembly to move up and down to cut cloth. Compared to existing structures, the cloth-cutting knife drive device of this differential-feed sewing machine integrates the cloth-cutting knife drive device into the space within and below the casing. This eliminates the need for additional accessories on the side of the casing and does not affect the inspection and adjustment of components within the sewing machine, making the installation layout of the cloth-cutting knife drive device more reasonable.

[0008] In the above-mentioned cloth cutting knife driving device of the differential feeding sewing machine, the cloth cutting knife assembly includes a cloth cutting knife, a knife holder, a guide frame and at least two guide posts. The cloth cutting knife is mounted on the guide frame through the knife holder. The guide frame has guide holes corresponding to the number and positions of the guide posts. The cloth cutting knife assembly also includes a control pin and a guide sleeve. The bottom of the knife rod has a connecting hole, and the guide sleeve has a protrusion that cooperates with the connecting hole. The guide frame has two upper and lower bosses at a position opposite to one end of the control pin, and the other end of the control pin has an operating member that can drive the control pin to extend into and out of the two bosses.

[0009] By arranging a guide frame on the cloth cutting knife assembly, the cloth cutting knife can be moved up and down more stably and is not easily deviated to one side; the operating part can realize the clutch of the cloth cutting knife. When the operating part drives the control pin to move backward and disengage from the two bosses, the control pin will not drive the guide frame to move up and down, thereby keeping the cloth cutting knife stationary; when the cloth cutting knife needs to work, the operating part drives the control pin to move forward to between the two bosses, and the control pin can drive the guide frame to move up and down, thereby making the cloth cutting knife move up and down to cut the cloth.

[0010] Preferably, in the aforementioned cloth cutting knife drive device for a differential feed sewing machine, the guide frame has a sliding portion at the front end, the knife holder is slidably connected to the sliding portion, and the guide sleeve is located on one side of the operating member and has an end cap detachably connected thereto. The position of the cloth cutting knife can be adjusted by changing the position of the knife holder on the sliding portion, and the detachable end cap facilitates installation of the control pin into the guide sleeve and prevents the operating member from being separated from the guide sleeve.

[0011] Preferably, in the aforementioned cloth cutting knife drive device for a differential feed sewing machine, one of the guide posts has a limiting ridge for abutment by the upper end face of the guide frame, and the other guide post is movably connected to the bottom of the housing via a connecting portion having a strip-shaped hole. This structure enables adjustment of the cloth cutting knife position and serves as a limiting position for the cloth cutting knife.

[0012] Preferably, in the aforementioned cloth cutting knife driving device for a differential feed sewing machine, a wrench is provided on an upper portion of the guide frame, the other end of the wrench extending outside the housing, and a spring is provided between the wrench and the housing. The cloth cutting knife can be manually lowered by the wrench extending outside the housing, and is reset by the spring when the wrench is released.

[0013] As another solution, in the aforementioned cloth cutting knife drive device for a differential feed sewing machine, the cloth cutting knife assembly includes a cloth cutting knife, a knife holder, a guide frame, and a guide post. The cloth cutting knife is fixed to the guide frame via the knife holder. The guide frame has a guide hole that mates with the guide post, and the guide frame is fixedly connected to the knife rod. This structure of the cloth cutting knife assembly is simple in structure and occupies less space.

[0014] In the aforementioned cloth-cutting knife drive device for a differential-feed sewing machine, the front end of the upper shaft further comprises a crank for driving the needle bar. The eccentric portion of the eccentric wheel has a first pin hole near the front end of the crank. The crank has a second pin hole directly opposite the first pin hole. Fixed pins are inserted into the first and second pin holes to connect the eccentric wheel and the crank. The eccentric wheel and the crank are connected via the first and second pin holes, enabling coordinated movement of the needle bar and the cloth-cutting knife. In actual production and manufacturing, the relative movement of the cloth-cutting knife and the needle bar can be controlled by varying the first and second pin holes.

[0015] In the above-mentioned cloth cutting knife drive device of the differential feed sewing machine, a differential feed shaft and a swing seat are also installed in the housing. The upper shaft and the differential feed shaft are connected to the swing seat via a connecting rod mechanism. The differential feed shaft is sleeved with a swing sleeve shaft, and a first bevel gear is fixed to the swing sleeve shaft. A drive motor is fixed to the housing, and a second bevel gear is fixed to the output shaft of the drive motor, which cooperates with the first bevel gear. The swing sleeve shaft has a swing mechanism connected to the swing seat and capable of driving the swing seat to swing near the rear end. The cooperation between the first and second bevel gears can effectively transmit the torque of the drive motor to the swing sleeve shaft, thereby better driving the swing sleeve shaft to rotate.

[0016] In the aforementioned cloth cutting knife drive device for a differential feed sewing machine, the swing mechanism includes a rear crank and a swing connecting rod. One end of the rear crank is fixed to a swing sleeve shaft, and the other end is connected to the swing connecting rod. The swing seat has an adjustment portion connected to the swing connecting rod on the side near the rear crank. The swing mechanism, consisting of the rear crank and the swing connecting rod, can be connected to the adjustment portion on the existing swing seat, so that when the swing sleeve shaft swings, the swing seat can also swing accordingly. The adjustment portion is located on the side of the swing seat near the rear crank, so that the rear crank can be directly connected to the adjustment portion via the swing connecting rod, without the need for additional connectors, resulting in a more compact structure.

[0017] In the above-mentioned cloth cutting knife driving device of the differential feeding sewing machine, the connecting rod mechanism includes a tooth lifting connecting rod, a feeding crank, an inner swing plate and an outer swing plate. The swing seat is rotatably connected to the casing through a pin shaft. The swing seat has a receiving groove. There are two pairs of inner swing plates and outer swing plates and both are located in the receiving groove. One end of the tooth lifting connecting rod is eccentrically connected to the upper shaft, and the other end extends into the receiving groove. The two sides of the end of the tooth lifting connecting rod extending into the receiving groove are respectively hinged to the rear ends of the inner swing plate and the outer swing plate; one end of the feeding crank is fixed on the differential feeding shaft, and the other end extends into the receiving groove. The front end of the inner swing plate is respectively hinged to the two sides of the feeding crank, and the front end of the outer swing plate is respectively hinged to the inner side of the swing seat close to the receiving groove.

[0018] During feeding, the upper shaft rotates to drive the tooth-lifting connecting rod to reciprocate, and drives the differential feeding shaft to swing through the outer swing plate, inner swing plate and feeding crank; when the output shaft of the driving motor drives the swing sleeve to swing through the bevel gear 1 and bevel gear 2, the swing sleeve drives the angle of the swing seat to change through the rear crank and the swing connecting rod, and then changes the angle between the inner swing plate and the outer swing plate, and then causes the swing amplitude and direction of the differential feeding shaft to change accordingly, thereby realizing the adjustment of the differential feeding speed and direction through the swing of the swing seat.

[0019] Compared with the existing technology, the advantages of this utility model patent are:

[0020] 1. The cloth cutting knife driving device of the differential feed sewing machine is provided with an eccentric wheel integrating eccentric part 1 and eccentric part 2, so that the upper shaft rotates to drive the eccentric connecting rod to drive the presser foot and at the same time drive the cloth cutting knife connecting rod to swing, and the sliding block on the knife bar joint cooperates with the slide rail to convert the swing of the cloth cutting knife connecting rod into up and down movement, thereby achieving the goal of placing the cloth cutting knife driving device inside the casing and below the front end of the casing to avoid occupying the side space of the casing.

[0021] 2. The cloth cutting knife driving device of this differential feed sewing machine is equipped with a guide frame, which makes the cloth cutting knife more stable and the position adjustment of the cloth cutting knife more convenient.

[0022] 3. The swing seat of the cloth cutting knife driving device of the differential feeding sewing machine is driven by the bevel gears arranged on the driving motor and the swing sleeve shaft, thereby improving the adjustment stability and accuracy of the swing seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural diagram of the cloth cutting knife driving device of the differential feed sewing machine.

[0024] Figure 2 The present invention is a schematic diagram of the internal structure of the casing of the cloth cutting knife drive device of the differential feed sewing machine.

[0025] Figure 3 This is a partial structural diagram of the cloth cutting knife drive device of the differential feed sewing machine.

[0026] Figure 4 The present invention is a cross-sectional schematic diagram of the connection structure between the cutter bar and the guide sleeve in the cloth cutting knife driving device of the differential feed sewing machine.

[0027] Figure 5 The present invention is a schematic diagram of the structure of an eccentric wheel in a cloth cutting knife driving device of a differential feed sewing machine.

[0028] Figure 6 The present invention is a structural diagram of a guide frame in a cloth cutting knife driving device of a differential feed sewing machine.

[0029] Figure 7 This is a schematic diagram of the differential feeding structure in the cloth cutting knife drive device of the differential feeding sewing machine.

[0030] In the figure, 1, housing; 2, presser foot; 3, needle bar; 4, upper shaft; 5, eccentric connecting rod; 6, cloth cutting knife connecting rod; 7, eccentric wheel; 71, mounting hole; 72, eccentric part 1; 73, eccentric part 2; 74, pin hole 1; 8, slide rail; 9, knife bar; 91, connecting hole; 10, knife bar joint; 11, slide block; 12, cloth cutting knife; 13, knife holder; 14, guide frame; 141, guide hole; 142, boss; 143, sliding part; 15, guide column; 16, control pin; 17, guide sleeve; 171, boss; 18, operation Working piece; 19. End cover; 20. Limiting ridge; 21. Connecting part; 211. Strip hole; 22. Wrench; 23. Spring; 24. Crank; 241. Pin hole 2; 25. Pin shaft; 26. Differential feed shaft; 27. Swing seat; 271. Adjustment part; 272. Accommodation groove; 28. Swing sleeve shaft; 29. Bevel gear 1; 30. Driving motor; 301. Output shaft; 31. Bevel gear 2; 32. Rear crank; 33. Swing connecting rod; 34. Lifting connecting rod; 35. Feed crank; 36. Inner swing plate; 37. Outer swing plate. DETAILED DESCRIPTION

[0031] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0032] Example 1:

[0033] The differential feed sewing machine includes a housing 1, a presser foot 2, a needle bar 3, and a cloth cutting knife 12. An upper shaft 4 is mounted within the housing 1, and an eccentric connecting rod 5 is mounted at the front end of the upper shaft 4 for driving the presser foot 2. The cloth cutting knife drive device of this differential feed sewing machine includes a cloth cutting knife connecting rod 6, an eccentric wheel 7, a knife bar 9, and a knife bar joint 10.

[0034] Specifically, if Figure 1 、 Figure 2 and Figure 5 As shown, the eccentric wheel 7 has a mounting hole 71 for the upper shaft 4 to pass through, and the eccentric wheel 7 has an eccentric portion 1 72 for mounting the eccentric connecting rod 5 and an eccentric portion 2 73 for mounting the cloth cutting knife connecting rod 6 on both sides. The eccentric portion 1 72 and the eccentric portion 2 73 are eccentrically arranged relative to the mounting hole 71, so that the upper shaft 4 rotates to drive the eccentric connecting rod 5 to drive the presser foot 2 while also driving the cloth cutting knife connecting rod 6 to swing. The front end of the upper shaft 4 also has a crank 24 for driving the needle bar 3 to move. The eccentric portion 1 72 of the eccentric wheel 7 has a pin hole 1 74 near the front end surface of the crank 24, and the crank 24 has a pin hole 241 that is opposite to the pin hole 1 74. A fixing pin is inserted into the pin hole 1 74 and the pin hole 2 241 to connect the eccentric wheel 7 and the crank 24. The eccentric wheel 7 is connected to the crank 24 through pin hole 1 74 and pin hole 2 241 to realize the coordinated action of the needle bar 3 and the cloth cutting knife 12. In the actual production and manufacturing process, the relative movement of the cloth cutting knife 12 and the needle bar 3 can be controlled by changing the pin hole 1 74 and pin hole 2 241.

[0035] like Figure 1 and Figure 2 As shown, a slide rail 8 is fixed in the housing 1, one end of the knife bar joint 10 is fixed to the knife bar 9, and the other end is slidably connected to the slide rail 8 via a slider 11. The cloth cutting knife connecting rod 6 is mounted in the middle of the knife bar joint 10, and the lower part of the knife bar 9 extends below the housing 1 and is connected to the cloth cutting knife 12 assembly and can drive the cloth cutting knife 12 assembly to move up and down. By providing the knife bar 9, the cloth cutting knife 12 assembly can be placed below the housing 1, effectively utilizing the space below the front end of the housing 1. The slider 11 connected to the knife bar joint 10 can slide up and down along the slide rail 8, converting the swing of the cloth cutting knife connecting rod 6 into the up and down movement of the knife bar 9, thereby driving the cloth cutting knife 12 assembly to move up and down to cut cloth.

[0036] like Figure 2 、 Figure 3 and Figure 6As shown, the cloth cutting knife 12 assembly includes a cloth cutting knife 12, a knife holder 13, a guide frame 14, a guide post 15, a control pin 16 and a guide sleeve 17. The cloth cutting knife 12 is mounted on the guide frame 14 through the knife holder 13. In this embodiment, there are two guide posts 15, and the guide frame 14 has guide holes 141 that correspond to the number and position of the guide posts 15. As a preferred embodiment, one of the guide posts 15 has a limiting ridge 20 for the upper end face of the guide frame 14 to abut, and the other guide post 15 is movably connected to the bottom of the casing 1 through a connecting portion 21 with a strip hole 211. This structure can adjust the position of the cloth cutting knife 12 and limit the position of the cloth cutting knife 12. By arranging the guide frame 14 in the cloth cutting knife 12 assembly, the cloth cutting knife 12 can be more stably moved up and down and is not easily deviated to one side. In the actual production and manufacturing process, the number of guide posts 15 can be more than two.

[0037] like Figure 3 、 Figure 4 and Figure 6 As shown, the bottom of the knife bar 9 has a connecting hole 91, and the guide sleeve 17 has a protrusion 171 that cooperates with the connecting hole 91. The guide frame 14 has two upper and lower bosses 142 at a position opposite to one end of the control pin 16. The other end of the control pin 16 has an operating member 18 that can drive the control pin 16 to extend into and out of the two bosses 142. The operating member 18 of the cloth cutting knife 12 assembly can achieve the clutch of the cloth cutting knife 12: when the control pin 16 is driven by the operating member 18 to move backward and disengage from the two bosses 142, the control pin 16 will not drive the guide frame 14 to move up and down, so that the cloth cutting knife 12 remains stationary; when the cloth cutting knife 12 needs to work, the control pin 16 is driven by the operating member 18 to move forward to between the two bosses 142, and the control pin 16 can drive the guide frame 14 to move up and down, so that the cloth cutting knife 12 moves up and down to cut the cloth.

[0038] like Figure 3 and Figure 4 As shown, as a preferred embodiment, the front end of the guide frame 14 has a sliding portion 143, the knife holder 13 is slidably connected to the sliding portion 143, and the guide sleeve 17 is located on one side of the operating member 18 and is detachably connected to the end cover 19. The position of the cloth cutting knife 12 can be adjusted by changing the position of the knife holder 13 on the sliding portion 143. The detachable end cover 19 facilitates the installation of the control pin 16 into the guide sleeve 17 and prevents the operating member 18 from being separated from the guide sleeve 17. A wrench 22 is provided on the upper part of the guide frame 14, and the other end of the wrench 22 extends out of the casing 1. A spring 23 is provided between the wrench 22 and the casing 1. The cloth cutting knife 12 can be manually lowered by extending the wrench 22 out of the casing 1. After releasing the wrench 22, it is reset under the action of the spring 23.

[0039] like Figure 1 、 Figure 2 and Figure 3As shown, the cloth cutting knife driving device of the differential feeding sewing machine integrates the cloth cutting knife driving device into the casing 1 and the space below the casing 1. There is no need to add additional accessories to the side of the casing 1 and it does not affect the replacement and adjustment of other parts in the casing 1, making the installation layout of the cloth cutting knife driving device more reasonable.

[0040] like Figure 1 、 Figure 2 and Figure 7 As shown, a differential feed shaft 26 and a swing seat 27 are also installed in the housing 1. The upper shaft 4 and the differential feed shaft 26 are connected to the swing seat 27 via a connecting rod mechanism. A swing sleeve 28 is sleeved on the differential feed shaft 26, and a bevel gear 1 29 is fixed to the swing sleeve 28. A drive motor 30 is fixed to the housing 1. A bevel gear 21 that cooperates with the bevel gear 1 29 is fixed to the output shaft 301 of the drive motor 30. The swing sleeve 28 has a swing mechanism near the rear end that is connected to the swing seat 27 and can drive the swing seat 27 to swing. The cooperation between the bevel gear 1 29 and the bevel gear 2 31 can effectively transmit the torque of the drive motor 30 to the swing sleeve 28, thereby better driving the swing sleeve 28 to rotate.

[0041] like Figure 2 and Figure 7 As shown, the swing mechanism includes a rear crank 32 and a swing link 33. One end of the rear crank 32 is fixed to the swing sleeve 28, and the other end is connected to the swing link 33. The side of the swing seat 27 near the rear crank 32 has an adjustment portion 271 connected to the swing link 33. The swing mechanism composed of the rear crank 32 and the swing link 33 can be connected to the adjustment portion 271 on the existing swing seat 27, so that when the swing sleeve 28 swings, the swing seat 27 can also swing accordingly. The adjustment portion 271 is located on the side of the swing seat 27 near the rear crank 32, so that the rear crank 32 can be directly connected to the adjustment portion 271 through the swing link 33, without the need for additional connectors, and the structure is more compact.

[0042] like Figure 2 and Figure 7 As shown, the connecting rod mechanism includes a tooth-lifting connecting rod 34, a feeding crank 35, an inner swing plate 36 and an outer swing plate 37. The swing seat 27 is rotatably connected to the casing 1 through the pin shaft 25. The swing seat 27 has a receiving groove 272. There are two pairs of inner swing plates 36 and outer swing plates 37 and both are located in the receiving groove 272. One end of the tooth-lifting connecting rod 34 is eccentrically connected to the upper shaft 4, and the other end extends into the receiving groove 272. The two sides of the end of the tooth-lifting connecting rod 34 extending into the receiving groove 272 are respectively hinged to the rear ends of the inner swing plate 36 and the outer swing plate 37; one end of the feeding crank 35 is fixed on the differential feeding shaft 26, and the other end extends into the receiving groove 272. The front ends of the inner swing plate 36 are respectively hinged to the two sides of the feeding crank 35, and the front ends of the outer swing plate 37 are respectively hinged to the inner side of the swing seat 27 near the receiving groove 272.

[0043] During feeding, the upper shaft 4 rotates to drive the tooth lifting connecting rod 34 to reciprocate, and drives the differential feeding shaft 26 to swing through the outer swing plate 37, the inner swing plate 36 and the feeding crank 35; when the output shaft 301 of the drive motor 30 drives the swing sleeve 28 to swing through the bevel gear 1 29 and the bevel gear 2 31, the swing sleeve 28 drives the angle of the swing seat 27 to change through the rear crank 32 and the swing connecting rod 33, and then changes the angle between the inner swing plate 36 and the outer swing plate 37, and then causes the swing amplitude and direction of the differential feeding shaft 26 to change accordingly, thereby realizing the adjustment of the differential feeding speed and direction through the swing of the swing seat 27.

[0044] Example 2:

[0045] The technical solution in this embodiment is basically the same as that in the first embodiment, except that, in this embodiment, the cloth cutting knife 12 assembly includes a cloth cutting knife 12, a knife holder 13, a guide frame 14, and a guide post 15. The cloth cutting knife 12 is fixed to the guide frame 14 via the knife holder 13. The guide frame 14 has a guide hole 141 that cooperates with the guide post 15. The guide frame 14 is fixedly connected to the knife rod 9. The cloth cutting knife 12 assembly of this structure is simple in structure and occupies less space.

[0046] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope defined by the appended claims.

Claims

1. A cloth cutting knife driving device for a differential feeding sewing machine, the differential feeding sewing machine comprising a housing (1), a presser foot (2), a needle bar (3) and a cloth cutting knife assembly, an upper shaft (4) being installed in the housing (1), an eccentric connecting rod (5) for driving the presser foot (2) being installed at the front end of the upper shaft (4), characterized in that: The cloth cutting knife driving device comprises a cloth cutting knife connecting rod (6) and an eccentric wheel (7), wherein the eccentric wheel (7) has a mounting hole (71) for the upper shaft (4) to pass through, and the two sides of the eccentric wheel (7) respectively have an eccentric part 1 (72) for mounting the eccentric connecting rod (5) and an eccentric part 2 (73) for mounting the cloth cutting knife connecting rod (6), and the eccentric part 1 (72) and the eccentric part 2 (73) are eccentrically arranged relative to the mounting hole (71); the cloth cutting knife The driving device also includes a knife bar (9) and a knife bar joint (10). A slide rail (8) is fixed in the housing (1). One end of the knife bar joint (10) is fixed on the knife bar (9), and the other end is slidably connected to the slide rail (8) through a slider (11). The cloth cutting knife connecting rod (6) is sleeved on the middle part of the knife bar joint (10). The lower part of the knife bar (9) extends below the housing (1) and is connected to the cloth cutting knife assembly and can drive the cloth cutting knife assembly to move up and down.

2. The cloth cutting knife driving device of the differential feed sewing machine according to claim 1, characterized in that: The cloth cutting knife assembly comprises a cloth cutting knife (12), a knife holder (13), a guide frame (14) and at least two guide posts (15). The cloth cutting knife (12) is mounted on the guide frame (14) through the knife holder (13). The guide frame (14) has guide holes (141) corresponding to the number and position of the guide posts (15). The cloth cutting knife assembly also comprises a control pin (16) and a guide sleeve (17). The bottom of the knife rod (9) has a connecting hole (91). The guide sleeve (17) has a protrusion (171) that cooperates with the connecting hole (91). The guide frame (14) has two upper and lower bosses (142) at a position opposite to one end of the control pin (16). The other end of the control pin (16) has an operating member (18) that can drive the control pin (16) to extend into and out of the two bosses (142).

3. The cloth cutting knife driving device of the differential feed sewing machine according to claim 2, characterized in that: The front end of the guide frame (14) has a sliding portion (143), the tool holder (13) is slidably connected to the sliding portion (143), and the guide sleeve (17) is located on one side of the operating member (18) and is detachably connected to an end cover (19).

4. The cloth cutting knife driving device of the differential feed sewing machine according to claim 2, characterized in that: One of the guide posts (15) has a limiting convex edge (20) for the upper end surface of the guide frame (14) to abut against, and the other guide post (15) is movably connected to the bottom of the housing (1) via a connecting portion (21) having a strip hole (211).

5. The cloth cutting knife driving device of the differential feed sewing machine according to claim 2, characterized in that: The guide frame (14) has a wrench (22) on its upper portion, the other end of the wrench (22) extends out of the casing (1), and a spring (23) is provided between the wrench (22) and the casing (1).

6. The cloth cutting knife driving device of the differential feed sewing machine according to claim 1, characterized in that: The cloth cutting knife assembly comprises a cloth cutting knife (12), a knife holder (13), a guide frame (14) and a guide column (15); the cloth cutting knife (12) is fixed on the guide frame (14) through the knife holder (13); the guide frame (14) has a guide hole (141) that cooperates with the guide column (15); and the guide frame (14) is fixedly connected to the knife rod (9).

7. The cloth cutting knife driving device of a differential feed sewing machine according to any one of claims 1 to 6, characterized in that: The front end of the upper shaft (4) also has a crank (24) for driving the needle rod (3) to move. The eccentric portion (72) of the eccentric wheel (7) has a pin hole (74) near the front end surface of the crank (24). The crank (24) has a pin hole (241) facing the pin hole (74). Fixed pins are inserted into the pin hole (74) and the pin hole (241) to connect the eccentric wheel (7) and the crank (24).

8. The cloth cutting knife driving device of the differential feed sewing machine according to claim 7, characterized in that: A differential feeding shaft (26) and a swing seat (27) are also installed in the housing (1). The upper shaft (4) and the differential feeding shaft (26) are connected to the swing seat (27) through a connecting rod mechanism. A swing sleeve shaft (28) is sleeved on the differential feeding shaft (26). A bevel tooth 1 (29) is fixed on the swing sleeve shaft (28). A driving motor (30) is fixed on the housing (1). A bevel tooth 2 (31) that matches the bevel tooth 1 (29) is fixed on the output shaft (301) of the driving motor (30). The swing sleeve shaft (28) has a swing mechanism connected to the swing seat (27) near the rear end and capable of driving the swing seat (27) to swing.

9. The cloth cutting knife driving device of the differential feed sewing machine according to claim 8, characterized in that: The swing mechanism comprises a rear crank (32) and a swing connecting rod (33); one end of the rear crank (32) is fixed on a swing sleeve (28), and the other end is connected to the swing connecting rod (33); the swing seat (27) has an adjusting portion (271) connected to the swing connecting rod (33) on a side close to the rear crank (32).

10. The cloth cutting knife driving device of the differential feed sewing machine according to claim 9, characterized in that: The connecting rod mechanism includes a tooth lifting connecting rod (34), a feeding crank (35), an inner swing plate (36) and an outer swing plate (37). The swing seat (27) is rotatably connected to the housing (1) through a pin shaft (25). The swing seat (27) has a receiving groove (272). There are two pairs of inner swing plates (36) and outer swing plates (37) and both are located in the receiving groove (272). One end of the tooth lifting connecting rod (34) is eccentrically connected to the upper shaft (4), and the other end extends into the receiving groove (27 2), the two sides of one end of the tooth-lifting connecting rod (34) extending into the receiving groove (272) are respectively hinged to the rear ends of the inner swing plate (36) and the outer swing plate (37); one end of the feeding crank (35) is fixed on the differential feeding shaft (26), and the other end extends into the receiving groove (272), the front end of the inner swing plate (36) is respectively hinged to the two sides of the feeding crank (35), and the front end of the outer swing plate (37) is respectively hinged to the inner side of the swing seat (27) close to the receiving groove (272).

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