A thread-cutting and thread-lifting module for a modular sewing machine and the modular sewing machine.

Abstract

This invention provides a lifting and thread-cutting module for a modular sewing machine and a modular sewing machine. The lifting and thread-cutting module includes a lifting and thread-cutting drive source, a lifting unit, a thread-cutting unit, and a clutch unit. The lifting and thread-cutting drive source is independent of other drive sources in the modular sewing machine and is connected to the lifting unit. The clutch unit is connected between the output end of the lifting and thread-cutting drive source and the thread-cutting unit, or between the lifting unit and the thread-cutting unit. The operating range of the lifting and thread-cutting drive source includes independent lifting and thread-cutting zones. When the lifting and thread-cutting drive source operates in the lifting zone, the clutch unit is in a disengaged state; when the lifting and thread-cutting drive source operates in the thread-cutting zone, the clutch unit is in a engaged state. This application integrates the lifting and thread-cutting functions into a single lifting and thread-cutting module, and switches between the lifting and thread-cutting functions through the clutch unit, ensuring that the lifting and thread-cutting functions do not interfere with each other.

Description

Technical Field

[0001] This invention relates to the field of sewing machines, and in particular to a modular sewing machine and a thread-cutting module for the modular sewing machine. Background Technology

[0002] Currently, all major sewing machine companies have their own design platforms. The feeding mechanism, the feed dog mechanism, the thread cutting mechanism, and the presser foot lifting mechanism are important functional mechanisms of a sewing machine. Once a company's design platform is determined, the development of its products and the next generation of products are all based on iterative updates of this design platform, and it is almost impossible to research and develop another completely new design platform.

[0003] Currently, sewing machines are all integrated machines, meaning they use a single main motor to simultaneously drive the needle insertion, thread take-up, feeding, and thread hooking processes, resulting in a very complex structure. For example, Figure 1 The existing sewing machine shown mainly includes a main motor, a main shaft 100 driven by the main motor, a thread take-up mechanism 200, a feeding mechanism 300, a thread hooking mechanism 400, a thread cutting mechanism 500, and a presser foot lifting mechanism 600. The thread take-up mechanism 200, the feeding mechanism 300, and the thread hooking mechanism 400 are all driven by the main shaft 100. The thread cutting cam in the thread cutting mechanism 500 is driven by the lower shaft in the thread hooking mechanism 400. The thread cutting mechanism 500 has a thread cutting drive source 501 independent of the main motor, and the presser foot lifting mechanism 600 has a presser foot lifting drive source 601 independent of the main motor. In existing sewing machines, when the main motor drives the main shaft 100 to rotate, the main shaft 100 drives the thread take-up mechanism 200, the feeding mechanism 300, and the hooking mechanism 400 to rotate. The thread take-up mechanism 200, the feeding mechanism 300, and the hooking mechanism 400 work together to complete the sewing. When it is necessary to cut the thread, the thread cutting drive source 501 is activated, causing the transmission component in the thread cutting mechanism 500 to engage with the thread cutting cam. The main shaft 100 rotates, causing the lower shaft in the hooking mechanism 400 to rotate, thereby causing the thread cutting mechanism 500 to perform the thread cutting action. When it is necessary to lift the presser foot, the presser foot lifting drive source 601 is activated, causing the presser foot lifting mechanism 600 to perform the presser foot lifting action.

[0004] The main structure of the feeding mechanism 300 is as follows: The feeding mechanism includes a tooth-lifting shaft and a feed shaft, both parallel to the main shaft; a first tooth-lifting unit connected between the main shaft and the tooth-lifting shaft; a second tooth-lifting unit connected between the tooth-lifting shaft and the rear end of the tooth holder; a first feed unit connected between the main shaft and the feed shaft; and a second feed unit connected between the feed shaft and the front end of the tooth holder. The main shaft drives the tooth holder and the feed teeth to reciprocate up and down through the first tooth-lifting unit, the tooth-lifting shaft, and the second tooth-lifting unit, performing the tooth-lifting action. The main shaft drives the tooth holder and the feed teeth to reciprocate back and forth through the first feed unit, the feed shaft, and the second feed unit, performing the feed action.

[0005] The main structure of the hook mechanism 400 is as follows: the hook mechanism includes a lower shaft parallel to the main shaft, a transmission shaft extending vertically, a bevel gear set connected between the main shaft and the upper end of the transmission shaft, a bevel gear set connected between the lower end of the transmission shaft and the right end of the lower shaft, and a rotary hook assembly fixed to the left end of the lower shaft.

[0006] The main structure of the wire cutting mechanism 500 is as follows: the wire cutting mechanism includes a wire cutting shaft parallel to the lower shaft, a wire cutting drive cam fixed on the lower shaft, a wire cutting clutch drive source, a moving blade, a first wire cutting unit connected to the right end of the wire cutting shaft, and a second wire cutting unit connected between the left end of the wire cutting shaft and the moving blade. When not cutting wire, the wire cutting clutch drive source does not operate, causing the first wire cutting unit to separate from the wire cutting drive cam; when cutting wire, the wire cutting clutch drive source operates, causing the first wire cutting unit to engage with the wire cutting drive cam, and subsequently, the rotation of the main shaft drives the moving blade to operate, thereby realizing wire cutting.

[0007] Therefore, as can be seen from the above structural description, the existing sewing machine's feeding mechanism (including front and rear feeding mechanisms, upper and lower lifting teeth mechanisms) and thread cutting mechanism have very complex structures, many parts, and long transmission chains. They require an additional clutch drive source to cooperate in realizing the thread cutting action. The feeding mechanism and thread cutting mechanism have single functions. When cutting the thread, the feed teeth may protrude upward from the needle plate, resulting in an unstable length of the thread left on the fabric after cutting. Summary of the Invention

[0008] In view of the shortcomings of the prior art described above, the technical problem to be solved by the present invention is to provide a lifting and thread-cutting module for a modular sewing machine, which integrates the lifting and thread-cutting functions into a single module that can be used as a whole in a modular sewing machine.

[0009] To achieve the above objectives, the present invention provides a tooth-lifting and thread-cutting module for a modular sewing machine, comprising a tooth-lifting and thread-cutting drive source, a tooth-lifting unit connected to a tooth-lifting connection at one end of the tooth frame, a thread-cutting unit, and a clutch unit. The tooth-lifting and thread-cutting drive source is independent of other drive sources in the modular sewing machine. The output end of the tooth-lifting and thread-cutting drive source is connected to the tooth-lifting unit. The clutch unit is connected between the output end of the tooth-lifting and thread-cutting drive source and the thread-cutting unit, or between the tooth-lifting unit and the thread-cutting unit.

[0010] The operating range of the tooth lifting and wire cutting drive source includes an independent tooth lifting zone and a wire cutting zone; when the tooth lifting and wire cutting drive source operates in the tooth lifting zone, the clutch unit is in a disengaged state; when the tooth lifting and wire cutting drive source operates in the wire cutting zone, the clutch unit is in a engaged state.

[0011] Furthermore, the clutch unit includes a first clutch cam driven to rotate by a thread-cutting drive source, a second clutch cam fixed on the thread-cutting shaft in the thread-cutting unit, and a first clutch ball. The first clutch ball is rotatably mounted on the first clutch cam and can contact the second clutch cam, or the first clutch ball is rotatably mounted on the second clutch cam and can contact the first clutch cam. The thread-cutting shaft is rotatably supported in the modular sewing machine base plate.

[0012] Furthermore, the clutch unit includes a third clutch cam driven to rotate by a thread-cutting drive source, a first clutch lever with a fixed rotation fulcrum, a second clutch ball rotatably mounted on the first clutch lever, a first clutch crank fixed on the thread-cutting shaft in the thread-cutting unit, a third clutch ball rotatably mounted on the first clutch crank, and a fourth clutch cam fixed on the lower shaft in the modular sewing machine. The second clutch ball can abut against the third clutch cam, and the third clutch ball can abut against the fourth clutch cam. The thread-cutting shaft is rotatably and movablely supported in the base plate of the modular sewing machine. The first clutch crank is provided with a pushing protrusion, and the first clutch lever abuts against the pushing protrusion.

[0013] Furthermore, the thread-cutting unit also includes a thread-cutting slider rotatably mounted on the first clutch crank, a thread-cutting crank shaft, a thread-cutting crank, a thread-cutting connecting rod, a moving blade holder, a moving blade fixed on the moving blade holder, and a fixed blade fixed on the base plate of the modular sewing machine. The thread-cutting crank shaft includes a transmission shaft portion parallel to the thread-cutting shaft and rotatably supported in the base plate of the modular sewing machine, and a crank portion integrally provided at one end of the transmission shaft portion. The crank portion has a thread-cutting groove that slides with the thread-cutting slider. The thread-cutting crank is fixed at the other end of the transmission shaft portion. The two ends of the thread-cutting connecting rod are respectively hinged to the thread-cutting crank and the moving blade holder.

[0014] Furthermore, the thread-cutting unit also includes a thread-cutting slider rotatably mounted on the first clutch crank, a thread-cutting crank shaft, a thread-cutting fork crank, a thread-cutting connecting rod, a main blade holder, an active blade fixed on the main blade holder, an auxiliary blade holder, and an auxiliary moving blade and a thread-cutting transmission pin, all fixed on the auxiliary blade holder. The thread-cutting crank shaft includes a transmission shaft portion parallel to the thread-cutting shaft and rotatably supported in the modular sewing machine base plate, and a crank portion integrally provided at one end of the transmission shaft portion. The crank portion has a thread-cutting groove that slides with the thread-cutting slider. The thread-cutting fork crank is fixed at the other end of the transmission shaft portion. The thread-cutting fork crank has a fork arm portion. The thread-cutting transmission pin is located in the fork of the fork arm portion, and the two slide with each other. The two ends of the thread-cutting connecting rod are respectively hinged to the thread-cutting fork crank and the main blade holder.

[0015] Furthermore, the clutch unit includes a second clutch crank driven to rotate by a thread-cutting drive source, a fourth clutch ball rotatably mounted on the second clutch crank, a first clutch connecting rod, and a transmission crank fixed on the thread-cutting shaft in the thread-cutting unit. The first clutch connecting rod has a free-stroke groove extending along its length direction. The fourth clutch ball is located in the free-stroke groove of the first clutch connecting rod, and the two are slidably engaged. The first clutch connecting rod is hinged to the transmission crank. The thread-cutting shaft is rotatably supported in the modular sewing machine base plate.

[0016] Furthermore, the tooth-lifting and thread-cutting drive source is a motor, and the tooth-lifting unit includes a tooth-lifting shaft rotatably supported in the modular sewing machine base plate, a tooth-lifting eccentric crank fixed on the tooth-lifting shaft, a tooth-lifting connecting rod, and a tooth-lifting pin. The tooth-lifting shaft is fixedly connected to the motor shaft of the tooth-lifting and thread-cutting drive source. One end of the tooth-lifting connecting rod is rotatably fitted onto the eccentric part of the tooth-lifting eccentric crank, and the other end of the tooth-lifting connecting rod is hinged to the tooth-lifting connection part of the tooth holder through the tooth-lifting pin.

[0017] Furthermore, the thread cutting unit also includes a thread cutting crank fixed on the thread cutting shaft, a thread cutting connecting rod, a moving blade holder, a moving blade fixed on the moving blade holder, and a fixed blade fixed on the base plate of the modular sewing machine. The two ends of the thread cutting connecting rod are respectively hinged to the thread cutting crank and the moving blade holder.

[0018] Furthermore, the wire cutting unit also includes a wire cutting fork crank fixed on the wire cutting shaft, a wire cutting connecting rod, a main blade holder, an active blade fixed on the main blade holder, an auxiliary blade holder, and an auxiliary moving blade and a wire cutting transmission pin both fixed on the auxiliary blade holder. The wire cutting fork crank has a fork arm portion, and the wire cutting transmission pin is located in the fork of the fork arm portion, with the two slidingly engaged. The two ends of the wire cutting connecting rod are respectively hinged to the wire cutting fork crank and the main blade holder.

[0019] Furthermore, the wire cutting unit also includes a wire cutting crank fixed on the wire cutting shaft, a wire cutting main connecting rod, a main blade holder, an active blade fixed on the main blade holder, a wire cutting auxiliary connecting rod, an auxiliary blade holder, and an auxiliary moving blade fixed on the auxiliary blade holder. The outer periphery of the wire cutting crank is provided with a first wire cutting arm and a second wire cutting arm that are circumferentially staggered. The two ends of the wire cutting main connecting rod are respectively hinged to the first wire cutting arm and the main blade holder, and the two ends of the wire cutting auxiliary connecting rod are respectively hinged to the second wire cutting arm and the auxiliary blade holder.

[0020] Furthermore, the clutch unit includes a fifth clutch cam driven to rotate by a wire-cutting drive source, a second clutch lever with a fixed rotation fulcrum, a fifth clutch ball rotatably mounted on the second clutch lever, and a second clutch link with one end hinged to the second clutch lever, the other end of which is connected to the wire-cutting unit for transmission.

[0021] Furthermore, the thread-cutting drive source is a motor, and the thread-cutting unit includes a thread-cutting shaft rotatably supported in the modular sewing machine base plate, a primary transmission assembly connecting the motor shaft of the thread-cutting drive source and the thread-cutting shaft, and a secondary transmission assembly connecting the thread-cutting shaft and the thread-cutting connection part of the feeder. The primary transmission assembly includes a thread-cutting eccentric wheel fixed on the motor shaft of the thread-cutting drive source, a primary thread-cutting connecting rod, and a primary thread-cutting crank fixed on the thread-cutting shaft. One end of the primary thread-cutting connecting rod is rotatably fitted onto the eccentric part of the thread-cutting eccentric wheel, and the other end of the primary thread-cutting connecting rod is hinged to the primary thread-cutting crank. The secondary transmission assembly includes a secondary thread-cutting crank fixed on the thread-cutting shaft and a secondary thread-cutting connecting rod. Both ends of the secondary thread-cutting connecting rod are respectively hinged to the secondary thread-cutting crank and the thread-cutting connection part of the feeder.

[0022] Furthermore, the wire cutting unit includes a wire cutting fork crank with a fixed rotation fulcrum, a wire cutting connecting rod, a main blade holder, an active blade fixed on the main blade holder, an auxiliary blade holder, an auxiliary moving blade fixed on the auxiliary blade holder, and a wire cutting transmission pin. The wire cutting fork crank has a fork arm portion. The second clutch connecting rod, the fork arm portion of the wire cutting fork crank, and the auxiliary blade holder are coaxially hinged through the wire cutting transmission pin. The wire cutting transmission pin is located in the fork of the fork arm portion, and the two are slidably engaged. The two ends of the wire cutting connecting rod are respectively hinged to the wire cutting fork crank and the main blade holder.

[0023] Furthermore, before the lifting and thread-cutting drive source reaches the end of the thread-cutting zone, the lifting and thread-cutting drive source prevents the feed dog of the modular sewing machine from emerging from the needle plate through the lifting unit.

[0024] The present invention also provides a modular sewing machine, wherein the modular sewing machine is equipped with the thread-cutting module described above.

[0025] As described above, the present invention relates to a thread-cutting module for a modular sewing machine and a modular sewing machine, which has the following features:

[0026] Beneficial effects:

[0027] This application integrates the lifting and thread-cutting functions into a lifting and thread-cutting module, which is driven separately by an independent lifting and thread-cutting drive source. It is suitable for modular sewing machines and effectively improves sewing adaptability. In particular, the lifting and thread-cutting functions of the lifting and thread-cutting module are switched through a clutch unit to ensure that the lifting and thread-cutting functions do not interfere with each other. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of a sewing machine in the prior art.

[0029] Figure 2 This is a structural schematic diagram of Embodiment 1 of the modular sewing machine of this application.

[0030] Figure 3 for Figure 2 Exploded view.

[0031] Figure 4 for Figure 2 A schematic diagram of the structure of the middle tooth unit.

[0032] Figure 5 for Figure 2 Schematic diagram of the clutch unit and the wire shearing unit.

[0033] Figures 6a to 6d for Figure 2 A schematic diagram of the clutch unit in different states during the wire cutting process of the lifting tooth cutting module.

[0034] Figure 7 for Figure 2 Diagram showing the state of the feed tooth when the eccentric crank and the feed connecting rod are collinear.

[0035] Figures 8a to 8c for Figure 2 Schematic diagrams of three embodiments of the operating angle distribution of the lifting tooth shearing drive source.

[0036] Figure 9 This is a structural schematic diagram of Embodiment 2 of the modular sewing machine of this application.

[0037] Figure 10 and Figure 11 for Figure 9 Schematic diagrams of the mid-lift tooth cutting module from different perspectives.

[0038] Figure 12 for Figure 9 A schematic diagram of the third clutch cam.

[0039] Figure 13 for Figure 9 A schematic diagram of the wire shearing unit in a single-moving-blade structure.

[0040] Figure 14 for Figure 9 A schematic diagram of the wire shearing unit with a double-moving blade structure in Embodiment 2.

[0041] Figure 15 for Figure 9 Schematic diagram of the operating angle distribution of the lifting tooth shearing drive source.

[0042] Figure 16 for Figure 9 Output angle of the lifting tooth shearing drive source State diagram of the tooth lifting unit.

[0043] Figure 17 for Figure 9The state diagram of the tooth-lifting unit when the tooth-lifting shearing drive source outputs the angle within the tooth-lifting zone.

[0044] Figure 18 for Figure 9 The state diagram of the tooth lifting unit when the tooth lifting shearing drive source outputs the angle within the shearing zone.

[0045] Figure 19 This is a structural schematic diagram of Embodiment 3 of the modular sewing machine of this application.

[0046] Figure 20 for Figure 19 A schematic diagram of the structure of the mid-lift tooth cutting module.

[0047] Figure 21 for Figure 19 A schematic diagram of the wire shearing unit in a single-moving-blade structure.

[0048] Figure 22 for Figure 19 A schematic diagram of the wire shearing unit with a double-moving blade structure in Embodiment 2.

[0049] Figure 23 for Figure 19 Schematic diagram of the operating angle distribution of the lifting tooth shearing drive source.

[0050] Figure 24 for Figure 19 Output angle of the lifting tooth shearing drive source State diagram of the tooth lifting unit.

[0051] Figure 25 for Figure 19 State diagram of the clutch unit when the output angle of the tooth-lifting zone is within the tooth-lifting zone by the tooth-lifting drive source.

[0052] Figure 26 for Figure 19 The state diagram of the tooth-lifting unit when the tooth-lifting shearing drive source outputs the angle within the tooth-lifting zone.

[0053] Figure 27 for Figure 19 State diagram of the clutch unit when the output angle of the wire cutting zone of the lifting tooth cutting drive source is as follows.

[0054] Figure 28 for Figure 19 The state diagram of the tooth lifting unit when the tooth lifting shearing drive source outputs the angle within the shearing zone.

[0055] Figure 29 This is a structural schematic diagram of Embodiment 4 of the modular sewing machine of this application.

[0056] Figure 30 for Figure 29 A schematic diagram of the structure of the middle tooth unit.

[0057] Figure 31 for Figure 29 Schematic diagram of the clutch unit and the wire shearing unit.

[0058] Figure 32 for Figure 29 A schematic diagram of the clutch cam and the tooth-lifting eccentric wheel.

[0059] Figure 33a and Figure 33b for Figure 29 A schematic diagram of the state of the center lifting thread cutting module during normal sewing.

[0060] Figure 34 for Figure 29 A schematic diagram of the state of the wire-cutting module during wire cutting.

[0061] Figure 35 for Figure 29 Output angle of the lifting tooth shearing drive source State diagram of the primary transmission component in the tooth-lifting unit.

[0062] Figures 36a to 36c for Figure 29 Schematic diagrams of three embodiments of the operating angle distribution of the lifting tooth shearing drive source.

[0063] Figure 37 for Figure 2 , Figure 9 , Figure 19 and Figure 29 A schematic diagram of the feeding module.

[0064] Component designation explanation

[0065] 10 Tooth-lifting and wire-cutting drive source

[0066] 20 dental frame

[0067] 21 Tooth-lifting connection

[0068] 22 Feeding connection section

[0069] 30 tooth lifting units

[0070] 31 Tooth lifting shaft

[0071] 32. Eccentric crank for tooth lifting

[0072] 33. Tooth-lifting linkage

[0073] 34. Tooth-lifting pin

[0074] 35 Eccentric tooth lifting wheel

[0075] 36 First-stage tooth lifting linkage

[0076] 37 First-stage tooth-lifting crank

[0077] 38 Second-stage tooth lifting crank

[0078] 39 Secondary tooth lifting linkage

[0079] 40 Wire Cutting Units

[0080] 41 Thread cutting spool

[0081] 42 Wire cutter slider

[0082] 43 Wire shearing crankshaft

[0083] 431 Wire Cutting Groove

[0084] 44 Wire-cutting crank

[0085] 45 Wire Cutting Rod

[0086] 46. ​​Moving tool holder

[0087] 47. Cutting

[0088] 48 Fixed tool

[0089] 49. Wire cutter fork crank

[0090] 410 Main tool holder

[0091] 411 Active Blade

[0092] 412 Auxiliary Tool Holder

[0093] 413 Auxiliary cutting tool

[0094] 414 Wire Cutting Drive Pin

[0095] 415 Wire Cutting Main Connector

[0096] 416 Wire Cutting Auxiliary Link

[0097] 417 Return Torsion Spring

[0098] 418 Forced Reset Pin

[0099] 419 Return Spring

[0100] 420 Forced Reset Ball

[0101] 421 Forced Reset Cam

[0102] 50 clutch unit

[0103] 51 First clutch cam

[0104] 511 Forced Reset Arm

[0105] 52 Second Clutch Cam

[0106] 53 First clutch ball bearing

[0107] 54 Third Clutch Cam

[0108] 541 Base circle segment

[0109] 542 Variable pitch surface segment

[0110] 55 First clutch lever

[0111] 56 Second clutch ball bearing

[0112] 57 First clutch crank

[0113] 571 push convex part

[0114] 58 Third clutch ball bearing

[0115] 59 Fourth clutch cam

[0116] 510 Second Clutch Crank

[0117] 511 Fourth clutch ball bearing

[0118] 512 First clutch linkage

[0119] 5121 Unloaded travel chute

[0120] 513 Transmission Crank

[0121] 514 Fifth Clutch Cam

[0122] 5141 Forced reset protrusion

[0123] 515 Second Clutch Lever

[0124] 516 Fifth Clutch Ball Bearing

[0125] 517 Second Clutch Linkage

[0126] 60 Feeding Module

[0127] 61 Feeding Driver

[0128] 62 Feed Crank

[0129] 63 Feeding Link

[0130] 64 Feeding shaft

[0131] 65 Dental bracket

[0132] 70. Delivery of cloth teeth

[0133] 80 Hook Module

[0134] 81 Hook Driver

[0135] 82 Lower Shaft

[0136] 90 stop block

[0137] 110 tension spring

[0138] 120 Stop pin

[0139] 130 limit block Detailed Implementation

[0140] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0141] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings of this specification are merely for illustrative purposes to aid those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0142] This invention provides a modular sewing machine, and more particularly, a thread-cutting module for the modular sewing machine. For ease of description, in the following embodiments, the length direction of the modular sewing machine is defined as the left-right direction, the width direction as the front-back direction, and the height direction as the up-down direction; simultaneously, the left direction is the direction towards the head of the modular sewing machine, the right direction is the direction towards the tail of the modular sewing machine, and the front direction is the direction of fabric movement when the modular sewing machine is sewing forward.

[0143] like Figure 2 or Figure 9 or Figure 19 or Figure 29 As shown, the modular sewing machine of the present invention is equipped with a feed dog and thread-cutting module, a feeding module 60, a needle-punch module, a thread take-up module, a thread hooking module 80, a feed dog frame 20, and a feed dog 70 fixedly mounted on the feed dog frame 20. The needle-punch module and the thread take-up module are not shown in the figure; as shown... Figure 19As shown, the hooking module 80 includes a hooking drive source 81, a lower shaft 82 rotatably supported in the modular sewing machine base plate, and a rotary hook assembly fixed to the left end of the lower shaft 82. The hooking drive source 81 is a motor, and the right end of the lower shaft 82 is connected to the motor shaft of the hooking drive source 81 via a coupling. The rear end and front end of the feeder 20 are respectively provided with a lifting feeder connection 21 and a feeding feeder connection 22. The lifting feeder connection 21 at the rear end of the feeder 20 is connected to the output end of the lifting feeder unit 30 in the lifting feeder and thread cutting module, and the feeding feeder connection 22 at the front end of the feeder 20 is connected to the output end of the feeding module 60. The lifting feeder and thread cutting module, the feeding module 60, the needle insertion module, the thread take-up module, and the hooking module 80 are functional modules of the modular sewing machine. The needle insertion module and the thread take-up module can be combined into a needle insertion and thread take-up module, or they can be two independent functional modules. In modular sewing machines, each functional module is driven by an independent drive source, ensuring that these modules operate independently and without interference. This shortens the transmission chain, avoiding vibration and noise issues caused by excessively long transmission chains. Furthermore, it allows for adjustment of the relative motion sequence and patterns of each module. For example, it allows for adjusting the timing of the hooking of the rotary hook in the hooking module 80 relative to the needle in the needle-piercing module, and adjusting the movement trajectory of the feed dog 70. This significantly improves sewing adaptability. Moreover, the modular sewing machine involved in this invention boasts powerful automation and intelligent functions, low cost, a good user experience, and wide applicability, greatly enhancing the overall competitiveness of the product.

[0144] like Figure 2 or Figure 9 or Figure 19 or Figure 29As shown, the thread-cutting module involved in this application includes a thread-cutting drive source 10, a thread-cutting unit 30, a thread-cutting unit 40, and a clutch unit 50. The thread-cutting drive source 10 is independent of other drive sources in the modular sewing machine. The output end of the thread-cutting drive source 10 is connected to the thread-cutting unit 30, and the output end of the thread-cutting unit 30 is connected to the thread-cutting connection part 21 at the rear end of the thread-cutting frame 20. The clutch unit 50 is connected between the output end of the thread-cutting drive source 10 and the thread-cutting unit 40, or between the thread-cutting unit 30 and the thread-cutting unit 40. The thread-cutting drive source 10 is a motor, such as a stepper motor or a servo motor. The operating range of the thread-cutting drive source 10 includes an independent thread-cutting area X1 and a thread-cutting area X2. The end point of the thread-cutting area X1 and the start point of the thread-cutting area X2 may or may not coincide. Specifically, when the modular sewing machine is performing sewing operations, the tooth lifting and thread cutting drive source 10 swings back and forth within a certain angle range in the tooth lifting area X1. This angle range corresponds to the set tooth lifting height of the modular sewing machine. During this process, the tooth lifting unit 30 drives the tooth holder 20 and the feed dog 70 to move up and down reciprocally to perform the tooth lifting action, and the feed module 60 drives the tooth holder 20 and the feed dog 70 to move back and forth reciprocally to perform the feed action. However, the clutch unit 50 is in the disengaged state of the transmission chain, so that the output torque of the tooth lifting and thread cutting drive source 10 is not transmitted to the thread cutting unit 40, and the thread cutting unit 40 does not operate. When the modular sewing machine needs to cut the thread, the lifting tooth thread cutting drive source 10 rotates from the lifting tooth area X1 in the positive direction to the thread cutting area X2. During the process of the lifting tooth thread cutting drive source 10 rotating from the starting point of the thread cutting area X2 to the ending point of the thread cutting area X2, the clutch unit 50 is in the transmission linkage engagement state, so that the output torque of the lifting tooth thread cutting drive source 10 is transmitted to the thread cutting unit 40 through the clutch unit 50, or through the components in the lifting tooth unit 30 and the clutch unit 50, driving the thread cutting unit 40 to perform the thread cutting action, thereby realizing automatic thread cutting.

[0145] Therefore, the feed dog lifting and thread cutting module and the feeding module 60 in this application together constitute the "feeding-feed dog lifting-thread cutting mechanism" of the modular sewing machine. The feed dog lifting and thread cutting module integrates the feed dog lifting function and the thread cutting function of the modular sewing machine. The lifting and thread cutting functions of the feed dog lifting and thread cutting module are switched through the clutch unit 50 to ensure that the lifting and thread cutting functions do not interfere with each other. It is driven by an independent feed dog lifting and thread cutting drive source 10, which is suitable for modular sewing machines and can effectively improve sewing adaptability: the lifting height of the feed dog 70 is changed by changing the swing amplitude of the feed dog lifting and thread cutting drive source 10; the actual stitch length is changed by changing the swing amplitude of the feeding drive source 61 in the feeding module 60; and various changes in the movement trajectory of the feed dog 70 are achieved by controlling the timing coordination between the feeding drive source 61 and the feed dog lifting and thread cutting drive source 10 in the feeding module 60, such as elliptical movement trajectory, equilateral triangle movement trajectory, inverse triangle movement trajectory, and rectangular movement trajectory.

[0146] Furthermore, the lifting unit 30, the thread cutting unit 40, and the clutch unit 50 in the lifting and thread cutting module have multiple preferred structures, thereby giving the lifting and thread cutting module multiple preferred embodiments, and correspondingly giving the modular sewing machine multiple preferred embodiments. The following provides one preferred embodiment of the feeding module 60 and four preferred embodiments of the lifting and thread cutting module.

[0147] Feeding module 60

[0148] like Figure 37 As shown, the feeding module 60 includes a feeding drive source 61 and a feeding unit connected to the feeding connection part 22 at the front end of the toothed frame 20. The tooth lifting and thread cutting drive source 10 and the feeding drive source 61 are two independent drive sources, and the feeding drive source 61 is also a motor. The feeding unit includes a feeding crank 62 driven to rotate by the feeding drive source 61, a feeding connecting rod 63, and a toothed frame seat 65 rotatably supported in the modular sewing machine base plate through a feeding shaft 64. The two ends of the feeding connecting rod 63 are hinged to the feeding crank 62 and the toothed frame seat 65, respectively. The toothed frame seat 65 is hinged to the feeding connection part 22 of the toothed frame 20. When the modular sewing machine is performing sewing operations, the feed drive source 61 swings back and forth within a certain angle range, driving the feed crank 62 and feed connecting rod 63 to drive the feeder seat 65 to swing back and forth, thereby driving the feed connecting part 22 and feed dog 70 of the feeder 20 to move back and forth, driving the feed dog 70 to perform forward and backward feeding actions.

[0149] Example 1 of tooth-lifting and wire-cutting module

[0150] like Figure 3 As shown, the clutch unit 50 includes a first clutch cam 51 driven to rotate by the thread-cutting drive source 10, a second clutch cam 52 fixed on the thread-cutting shaft 41 in the thread-cutting unit 40, and a first clutch ball 53. The thread-cutting shaft 41 is rotatably supported in the modular sewing machine base plate. The first clutch ball 53 is rotatably mounted on the first clutch cam 51 and can contact the second clutch cam 52, or the first clutch ball 53 is rotatably mounted on the second clutch cam 52 and can contact the first clutch cam 51. Figure 3 In the illustrated embodiment, the first clutch ball 53 is rotatably mounted on the first clutch cam 51, and the following embodiments are described using this structure as an example.

[0151] like Figure 8a or Figure 8b or Figure 8c As shown, the starting and ending points of the tooth-lifting zone X1 of the tooth-lifting shearing drive source 10 are respectively angles. and The starting and ending points of the wire-cutting zone X2 of the wire-lifting and wire-cutting drive source 10 are respectively angles. and When the modular sewing machine is sewing, if the toother lifting and thread-cutting drive source 10 oscillates back and forth within a certain angle range in the toother lifting area X1, there is no power transmission between the first clutch ball 53 and the second clutch cam 52. Therefore, there is also no power transmission between the first clutch cam 51 and the thread-cutting shaft 41, the thread-cutting shaft 41 does not rotate, and the thread-cutting unit 40 does not operate. When the modular sewing machine needs to cut the thread, the toother lifting and thread-cutting drive source 10 rotates from the toother lifting area X1 in the positive direction to the thread-cutting area X2. The positive direction is... Figure 8a or Figure 8b or Figure 8c In the counter-clockwise direction, the lifting tooth shearing drive source 10 starts from the beginning of the shearing zone X2. Turn forward to the end of the wire-cutting zone X2. During this process, power is transmitted between the first clutch ball 53 and the second clutch cam 52, and power is also transmitted between the first clutch cam 51 and the wire-cutting shaft 41. The first clutch cam 51 drives the second clutch cam 52 to rotate through the first clutch ball 53, and the wire-cutting shaft 41 rotates synchronously with the second clutch cam 52, driving the wire-cutting unit 40 to perform the wire-cutting action, thus realizing automatic wire cutting. Therefore, the clutch unit 50 can be understood as the wire-cutting transmission part of the lifting-tooth wire-cutting module; the wire-cutting unit 40 can be understood as the wire-cutting execution part of the lifting-tooth wire-cutting module.

[0152] In this embodiment, as Figure 6a and Figure 6b As shown, the outer circumferential surface of the second clutch cam 52 is provided with a variable diameter section. When the tooth-lifting and wire-cutting drive source 10 operates in the tooth-lifting area X1, the first clutch ball 53 and the second clutch cam 52 do not contact each other and are separated, so that there is no power transmission between the first clutch ball 53 and the second clutch cam 52. When the tooth-lifting and wire-cutting drive source 10 operates in the wire-cutting area X2, the first clutch ball 53 and the variable diameter section of the second clutch cam 52 contact each other, so that there is power transmission between the first clutch ball 53 and the second clutch cam 52. The first clutch cam 51 can drive the second clutch cam 52 and the wire-cutting shaft 41 to rotate through the first clutch ball 53. Of course, in other embodiments, an equal-diameter section can be provided on the outer peripheral surface of the second clutch cam 52; when the tooth lifting and shearing drive source 10 operates in the tooth lifting area X1, the first clutch ball 53 contacts the equal-diameter section of the second clutch cam 52, which can also make the first clutch ball 53 and the second clutch cam 52 without power transmission.

[0153] like Figure 2 and Figure 3As shown, the lifting unit 30 has a lifting shaft 31 parallel to the thread-cutting shaft 41. The lifting shaft 31 is rotatably supported in the modular sewing machine base plate. The motor shaft of the lifting and thread-cutting drive source 10 is connected to the right end of the lifting shaft 31 via a coupling, and the lifting and thread-cutting drive source 10 directly drives the lifting shaft 31 to rotate. The first clutch cam 51 is fixed to the motor shaft of the lifting and thread-cutting drive source 10 by screws, so the lifting and thread-cutting drive source 10 directly drives the first clutch cam 51 to rotate; or, the first clutch cam 51 is fixed to the lifting shaft 31 by screws, so the lifting and thread-cutting drive source 10 drives the first clutch cam 51 to rotate via the lifting shaft 31.

[0154] like Figure 4 As shown, the tooth lifting unit 30 also includes a tooth lifting eccentric crank 32, a tooth lifting connecting rod 33, and a tooth lifting pin 34 fixed to the left end of the tooth lifting shaft 31. One end of the tooth lifting connecting rod 33 is rotatably mounted on the eccentric part of the tooth lifting eccentric crank 32 via a bearing, and the other end of the tooth lifting connecting rod 33 is hinged to the tooth lifting connection part 21 of the tooth frame 20 via the tooth lifting pin 34. When the tooth lifting and wire cutting drive source 10 drives the tooth lifting shaft 31 and the tooth lifting eccentric crank 32 to swing back and forth within a certain angle range in the tooth lifting area X1, the tooth lifting connecting rod 33 drives the tooth lifting connection part 21 of the tooth frame 20 to move up and down reciprocally, thereby driving the feed tooth 70 to perform the up and down tooth lifting action.

[0155] Furthermore, when the wire-lifting and wire-cutting drive source 10 operates to the end point of the wire-cutting zone X2... The preceding (including the lifting wire cutting drive source 10 operating to the end point of the wire cutting zone X2) (At that time), the feed dog 70 of the modular sewing machine is prevented from emerging from the needle plate by the feed dog unit 30, that is, the feed dog 70 is lowered below the needle plate, realizing downward feeding during thread cutting. The feed dog 70 does not push the fabric upward, which can shorten the distance between the fabric and the thread cutting engagement point in the thread cutting unit 40, and shorten the length of the thread left on the fabric after cutting, thus stably achieving the effect of short thread cutting. Therefore, the action of the feed dog 70 being lowered from the needle plate by the feed dog unit 30 occurs within the thread cutting zone X2.

[0156] Furthermore, the tooth-lifting and wire-cutting drive source 10 outputs an angle. At that time, the modular sewing machine has a minimum effective tooth lifting height; the tooth lifting and thread cutting drive source 10 outputs an angle. At that time, the modular sewing machine has the maximum effective lifting height; the lifting thread cutting drive source 10 starts from the beginning of the lifting zone X1. Rotate in the positive direction to the end point of the tooth lifting zone X1. During the process, the effective lifting height of the sewing machine gradually increases. Additionally, the lifting and thread-cutting drive source 10 rotates from the lifting zone X1 in the positive direction to the end point of the thread-cutting zone X2. During this process, the tooth-lifting wire-cutting drive source 10 will output an angle. At this time, as Figure 7 As shown, the eccentric crank 32 and the lifting rod 33 are collinear, meaning the center of the lifting shaft 31, the center of the eccentric part of the lifting crank 32, and the center of the lifting pin 34 (i.e., the hinge center of the lifting rod 33 and the lifting connection 21 of the feed dog 20) are collinear. At this point, the feed dog 70 is in its extreme position, protruding upwards from the needle plate to its maximum distance. Specifically, the angle of the lifting thread cutting drive source 10... It must be smaller than the end point of the cut line area X2. To ensure the wire cutting is achieved during the cutting process, the angle of the wire cutting drive source 10 is adjusted accordingly. The following situations are possible: 1. For example Figure 8a As shown, II. Figure 8b As shown, III. Figure 8c As shown, Thus, during the thread cutting process, the height of the feed dog 70 changes as follows: it gradually increases from the current effective height to the corresponding height. The maximum effective tooth lifting height of the angle is gradually increased to the corresponding value. The maximum tooth lift height at the angle, then gradually decreasing to the corresponding... The negative angle of the feed dog height corresponds to the feed dog being 70 degrees below the needle plate.

[0157] The wire cutting unit 40 can adopt a single-moving blade structure or a double-moving blade structure; in this embodiment, the wire cutting unit 40 adopts a double-moving blade structure. Figure 5 As shown, the wire cutting unit 40 also includes a wire cutting crank 44 fixed to the left end of the wire cutting shaft 41, a wire cutting main connecting rod 415, a main blade holder 410, an active blade 411 fixed to the main blade holder 410, a wire cutting auxiliary connecting rod 416, an auxiliary blade holder 412, and an auxiliary moving blade 413 fixed to the auxiliary blade holder 412. The outer periphery of the wire cutting crank 44 is provided with a first wire cutting arm 441 and a second wire cutting arm 442 circumferentially staggered. Both ends of the wire cutting main connecting rod 415 are hinged to the first wire cutting arm 441 and the main blade holder 410 respectively via pins. Both ends of the wire cutting auxiliary connecting rod 416 are hinged to the second wire cutting arm 442 and the auxiliary blade holder 412 respectively via pins. The wire cutting drive source 10 starts from the wire cutting zone X2. Turn forward to the end of the wire-cutting zone X2. During this process, the thread cutting shaft 41 drives the thread cutting crank 44 to rotate. The thread cutting crank 44 drives the main blade holder 410 and the auxiliary blade holder 412 to rotate in opposite directions around the lower shaft 82 in the thread hooking module 80 through the main thread cutting connecting rod 415 and the auxiliary thread cutting connecting rod 416, respectively, so that the active blade 411 and the auxiliary moving blade 413 rotate in opposite directions until the two bite together to cut the sewing thread.

[0158] Preferably, such as Figure 5 As shown, the thread-cutting unit 40 also includes a return torsion spring 417 sleeved around the outer periphery of the thread-cutting shaft 41, and a stop block 90 fixed to the modular sewing machine base plate. The two ends of the return torsion spring 417 are connected to the thread-cutting crank 44 and the modular sewing machine base plate, respectively. After thread cutting is completed, the thread-cutting drive source 10 moves from the end point of the thread-cutting zone X2... Reverse to the starting point of the cut line zone X2. During this process, the spring force of the reset spring 419 drives the wire cutting crank 44 to rotate in the opposite direction. The wire cutting crank 44 drives the main blade holder 410 and the auxiliary blade holder 412 to rotate in the opposite direction around the lower shaft 82 in the hooking module 80 through the main wire cutting connecting rod 415 and the auxiliary wire cutting connecting rod 416, respectively, so that the active blade 411 and the auxiliary moving blade 413 rotate in the opposite direction and reset themselves until the wire cutting crank 44 is restricted to its initial position by the stop block 90.

[0159] Furthermore, such as Figures 6a to 6d As shown, a forced reset arm 511 is provided on the outer periphery of the first clutch cam 51, and a forced reset pin 418 is fixed on the second clutch cam 52; during the wire cutting process, as Figure 6a and Figure 6b As shown, the first clutch ball 53 contacts the variable diameter section of the second clutch cam 52; during the reset process of the wire cutting unit 40 after wire cutting, the lifting wire cutting drive source 10 rotates in the opposite direction, driven by the reset torsion spring 417 on one hand, and forced to rotate the reset arm 511 towards the forced reset pin 418 on the other hand. Figure 6c and Figure 6d As shown, after the forced reset arm 511 abuts against the forced reset pin 418, the first clutch cam 51 drives the second clutch cam 52 to rotate in the opposite direction to perform forced reset, thus avoiding the failure of the active blade 411 and the auxiliary blade 413 to be unable to reset smoothly due to being stuck by lint.

[0160] Example 2 of the tooth-lifting and wire-cutting module

[0161] like Figure 10 and Figure 11As shown, the clutch unit 50 includes a third clutch cam 54 driven to rotate by the thread-cutting drive source 10, a first clutch lever 55 with a fixed rotation fulcrum, a second clutch ball 56 rotatably mounted on one end of the first clutch lever 55, a first clutch crank 57 fixed on the thread-cutting shaft 41 in the thread-cutting unit 40, a third clutch ball 58 rotatably mounted on the first clutch crank 57, and a fourth clutch cam 59 fixed on the lower shaft 82 of the modular sewing machine. The first clutch lever 55 is hinged to the base plate of the modular sewing machine by a pin extending vertically. The thread-cutting shaft 41 is rotatably and movablely supported in the base plate of the modular sewing machine. A protruding pushing protrusion 571 is integrally provided on the outer peripheral surface of the first clutch crank 57, and the other end of the first clutch lever 55 abuts against the pushing protrusion 571.

[0162] like Figure 15 As shown, the starting and ending points of the tooth-lifting zone X1 of the tooth-lifting shearing drive source 10 are respectively angles. and The starting and ending points of the wire-cutting zone X2 of the wire-lifting and wire-cutting drive source 10 are respectively angles. and In this embodiment, That is, the end point of the lifting zone X1 coincides with the starting point of the thread-cutting zone X2. When the modular sewing machine is performing sewing operations, the lifting and thread-cutting drive source 10 oscillates back and forth within a certain angle range in the lifting zone X1. There is no power transmission between the third clutch cam 54 and the second clutch ball 56, so the first clutch lever 55 does not rotate. Therefore, the first clutch lever 55 does not push the first clutch crank 57 and the thread-cutting shaft 41, causing the third clutch ball 58 on the first clutch crank 57 to move away from the fourth clutch cam 59 on the lower shaft 82. Thus, the third clutch ball 58 and the fourth clutch cam 59 do not contact each other and there is no power transmission. Therefore, the lower shaft 82 will not drive the first clutch crank 57 and the thread-cutting shaft 41 to rotate, and the thread-cutting unit 40 will not operate. When the modular sewing machine needs to cut the thread, the lifting and thread-cutting drive source 10 rotates from the lifting zone X1 in the positive direction to the thread-cutting zone X2. The positive direction is... Figure 15 The clockwise direction in the view; from the starting point of the cutting zone X2 at the tooth-lifting shearing drive source 10. Turn forward to the end of the wire-cutting zone X2. During this process, there is a power transmission between the third clutch cam 54 and the second clutch ball 56. The third clutch cam 54 pushes the first clutch lever 55 to rotate through the second clutch ball 56. The first clutch lever 55 pushes the first clutch crank 57 and the wire cutting shaft 41 to move to the left, so that the third clutch ball 58 on the first clutch crank 57 is close to the fourth clutch cam 59. Then the third clutch ball 58 is located on the outer periphery of the fourth clutch cam 59. In this way, the lower shaft 82 rotates, and the fourth clutch cam 59 rotates with the lower shaft 82. The fourth clutch cam 59 pushes the first clutch crank 57 to rotate through the third clutch ball 58. The wire cutting shaft 41 rotates with the first clutch crank 57, thereby driving the wire cutting unit 40 to perform the wire cutting action and realize automatic wire cutting.

[0163] Furthermore, such as Figure 12 As shown, the third clutch cam 54 is an end-face cam, meaning its side end face is a cam surface, which has a base circle section 541 and a variable pitch section 542. When the lifting wire shearing drive source 10 operates in the lifting area X1, the second clutch ball 56 contacts the base circle section 541, resulting in no power transmission between the second clutch ball 56 and the third clutch cam 54, and the third clutch cam 54 does not transmit torque to the first clutch lever 55. When the lifting wire shearing drive source 10 operates in the shearing area X2, the second clutch ball 56 contacts the variable pitch section 542, resulting in power transmission between the second clutch ball 56 and the third clutch cam 54, and the third clutch cam 54 transmits torque to the first clutch lever 55 through the second clutch ball 56. Preferably, as shown... Figure 10 and Figure 11 As shown, the thread-cutting module also includes a tension spring 110 fixed to the right end of the modular sewing machine base plate. The left end of the tension spring 110 is connected to the first clutch lever 55, and the connection point between the tension spring 110 and the first clutch lever 55 is located on the side of the fixed rotation fulcrum of the first clutch lever 55 facing away from the second clutch ball 56. In this way, the force applied by the tension spring 110 to the first clutch lever 55 can make the second clutch ball 56 closely adhere to the cam surface of the third clutch cam 54, ensuring the accuracy of thread cutting and subsequent reset. In addition, in other embodiments, when the thread-cutting drive source 10 operates in the thread-cutting area X1, the second clutch ball 56 and the third clutch cam 54 do not contact each other, so that there is no power transmission between the second clutch ball 56 and the third clutch cam 54.

[0164] Furthermore, such as Figure 11As shown, the fourth clutch cam 59 is a cylindrical cam, meaning its outer circumferential surface has a variable diameter section. When the tooth-lifting and wire-cutting drive source 10 operates within the tooth-lifting area X1, the third clutch ball 58 is away from and does not contact the fourth clutch cam 59, resulting in no power transmission between them. When the tooth-lifting and wire-cutting drive source 10 operates within the wire-cutting area X2, the third clutch ball 58 is located on the outer circumference of the fourth clutch cam 59. As the lower shaft 82 drives the fourth clutch cam 59 to rotate, the third clutch ball 58 can contact the variable diameter section of the fourth clutch cam 59, allowing power transmission between them.

[0165] Furthermore, such as Figure 10 and Figure 11 As shown, the lifting unit 30 has a lifting shaft 31 parallel to the thread-cutting shaft 41 and rotatably supported in the modular sewing machine base plate. The motor shaft of the lifting and thread-cutting drive source 10 is connected to the right end of the lifting shaft 31 via a coupling, and the lifting and thread-cutting drive source 10 directly drives the lifting shaft 31 to rotate. The third clutch cam 54 is fixed to the motor shaft of the lifting and thread-cutting drive source 10 by screws, so the lifting and thread-cutting drive source 10 directly drives the third clutch cam 54 to rotate; or, the third clutch cam 54 is fixed to the lifting shaft 31 by screws, so the lifting and thread-cutting drive source 10 drives the third clutch cam 54 to rotate via the lifting shaft 31.

[0166] like Figure 10 and Figure 11 As shown, the tooth lifting unit 30 also includes a tooth lifting eccentric crank 32, a tooth lifting connecting rod 33, and a tooth lifting pin 34 fixed to the left end of the tooth lifting shaft 31. One end of the tooth lifting connecting rod 33 is rotatably mounted on the eccentric part of the tooth lifting eccentric crank 32 via a bearing, and the other end of the tooth lifting connecting rod 33 is hinged to the tooth lifting connection part 21 of the tooth frame 20 via the tooth lifting pin 34. When the tooth lifting and wire cutting drive source 10 drives the tooth lifting shaft 31 and the tooth lifting eccentric crank 32 to swing back and forth within a certain angle range in the tooth lifting area X1, the tooth lifting connecting rod 33 drives the tooth lifting connection part 21 of the tooth frame 20 to move up and down reciprocally, thereby driving the feed tooth 70 to perform the up and down tooth lifting action.

[0167] Furthermore, in this application, the tooth-lifting wire-cutting drive source 10 outputs an angle. At that time, the modular sewing machine has a minimum effective tooth lifting height. The tooth lifting and thread cutting drive source 10 outputs an angle... and At times, such as Figure 16As shown, the eccentric crank 32 and the lifting rod 33 are collinear, meaning the center of the lifting shaft 31, the center of the eccentric part of the lifting crank 32, and the center of the lifting pin 34 (i.e., the hinge center of the lifting rod 33 and the lifting connection part 21 of the feed dog 20) are collinear. The feed dog 70 is in its extreme position, and the feed dog 70 protrudes upwards from the needle plate to its maximum distance, giving the modular sewing machine its maximum effective lifting height. Specifically, the lifting thread cutting drive source 10 outputs an angle... At this time, the modular sewing machine has a negative feed dog height, which corresponds to the feed dog 70 being below the needle plate. That is, the negative feed dog height at or before this moment. The feed dog lifting and thread cutting drive source 10, through the feed dog lifting unit 30, prevents the feed dog 70 of the modular sewing machine from protruding from the needle plate, causing the feed dog 70 to sink below the needle plate. This achieves downward feeding during thread cutting, preventing the feed dog 70 from pushing the fabric upwards. This shortens the distance between the fabric and the thread cutting engagement point in the thread cutting unit 40, reducing the length of the thread end remaining on the fabric after cutting and stably achieving a short thread cutting effect. Therefore, the feed dog lifting and thread cutting drive source 10 starts from the beginning of the feed dog lifting area X1. Rotate in the positive direction to the end point of the tooth lifting zone X1. During the process, the lifting height of the feed dog 70 gradually increases; when the lifting wire shearing drive source 10 operates within the lifting zone X1, the postures of the lifting eccentric crank 32 and the lifting connecting rod 33 are as follows: Figure 17 As shown. The wire-lifting and wire-cutting drive source 10 starts from the beginning of the wire-cutting zone X2. Rotate in the positive direction to the end of the shearing zone X2. During the process, the lifting height of the feed dog 70 gradually decreases; when the lifting and shearing drive source 10 operates within the shearing zone X2, the postures of the lifting eccentric crank 32 and the lifting connecting rod 33 are as follows: Figure 18 As shown.

[0168] Furthermore, the wire cutting unit 40 can adopt a single-moving blade structure or a double-moving blade structure, thus giving the wire cutting unit 40 the following two embodiments.

[0169] Example 1 of the wire-cutting unit 40 Figure 9 , Figure 10 ,as well as Figure 13As shown, the single-acting-blade thread-cutting unit 40 includes a thread-cutting slider 42 rotatably mounted on a first clutch crank 57, a thread-cutting crank shaft 43, a thread-cutting crank 44, a thread-cutting connecting rod 45, a moving blade holder 46, a moving blade 47 fixed on the moving blade holder 46, and a fixed blade 48 fixed on the base plate of the modular sewing machine. The thread-cutting crank shaft 43 includes a transmission shaft portion parallel to the thread-cutting shaft 41 and rotatably supported in the base plate of the modular sewing machine, and a crank portion integrally provided at the right end of the transmission shaft portion. The crank portion has a thread-cutting groove 431 that slides with the thread-cutting slider 42. The thread-cutting groove 431 is through the left and right sides. The thread-cutting crank 44 is fixed at the left end of the transmission shaft portion. The two ends of the thread-cutting connecting rod 45 are respectively hinged to the thread-cutting crank 44 and the moving blade holder 46.

[0170] Example 2 of the wire-cutting unit 40 Figure 9 , Figure 10 ,as well as Figure 14 As shown, the double-moving-blade thread-cutting unit 40 includes a thread-cutting slider 42 rotatably mounted on a first clutch crank 57, a thread-cutting crank shaft 43, a thread-cutting fork crank 49, a thread-cutting connecting rod 45, a main blade holder 410, an active blade 411 fixed on the main blade holder 410, an auxiliary blade holder 412, and auxiliary moving blades 413 and thread-cutting transmission pins 414, all fixed on the auxiliary blade holder 412. The thread-cutting crank shaft 43 includes components parallel to the thread-cutting shaft 41 and rotatably supported on the modular seam. The base plate of the sewing machine has a drive shaft and a crank portion integrally located at the right end of the drive shaft. The crank portion has a thread cutting groove 431 that slides with the thread cutting slider 42. The thread cutting groove 431 is open from left to right. The thread cutting fork crank 49 is fixed at the left end of the drive shaft. The thread cutting fork crank 49 has a fork arm portion. The thread cutting transmission pin 414 is located in the fork of the fork arm portion, and the two slide with each other. The two ends of the thread cutting connecting rod 45 are respectively hinged to the thread cutting fork crank 49 and the main blade holder 410.

[0171] In the above-described embodiment of the thread-cutting unit 40, the thread-cutting groove 431 at the right end of the thread-cutting crank shaft 43 and the thread-cutting slider 42 form a sliding pair. Preferably, the thread-cutting unit 40 further includes a return torsion spring 417 sleeved on the outer periphery of the left section of the thread-cutting crank shaft 43 and a return spring 419 sleeved on the thread-cutting shaft 41; in the first embodiment of the thread-cutting unit 40, the two ends of the return torsion spring 417 are respectively connected to the thread-cutting crank 44 and the modular sewing machine base plate; in the second embodiment of the thread-cutting unit 40, the two ends of the return torsion spring 417 are respectively connected to the thread-cutting fork crank 49 and the modular sewing machine base plate; the left end of the return spring 419 is fixed, and the right end of the return spring 419 abuts against the first clutch crank 57. After the wire cutting is completed, the reset torsion spring 417 causes the wire cutting crank 44 or the wire cutting fork crank 49 to reverse and reset, the tension spring 110 causes the first clutch lever 55 to reverse and reset, and the reset spring 419 causes the first clutch crank 57 to move to the right and reset, thereby resetting the components in the wire cutting unit 40 and the clutch unit 50.

[0172] Furthermore, such as Figure 11 As shown, a rotatable forced return ball 420 is also installed on the first clutch crank 57, and a forced return cam 421 is integrally provided on one end of the fourth clutch cam 59. After the wire cutting is completed, the wire lifting and cutting drive source 10 starts from the end point of the wire cutting area X2. During the reset process in the opposite direction, the reset is driven by the reset torsion spring 417. If a reset failure occurs, the forced reset ball 420 will contact the cam surface on the outer periphery of the forced reset cam 421, forcibly driving the first clutch crank 57 to rotate in the opposite direction for forced reset. This avoids the failure of the moving blade 47 and the fixed blade 48, or the active blade 411 and the auxiliary moving blade 413, to be unable to reset smoothly due to being stuck by wire. In this embodiment, the first clutch crank 57 has a first crank arm at its right end and a second crank arm and a third crank arm at its left end. The first, second, and third crank arms are staggered in the circumferential direction. The third clutch ball 58 is installed at the outer end of the first crank arm, the wire cutter slider 42 is installed at the outer end of the second crank arm, and the forced reset ball 420 is installed at the outer end of the third crank arm.

[0173] Example 3 of tooth-lifting and wire-cutting module

[0174] like Figure 20 As shown, the clutch unit 50 includes a second clutch crank 510 driven to rotate by the lifting tooth thread-cutting drive source 10, a fourth clutch ball 511 rotatably mounted on the left end face of the outer end of the second clutch crank 510, a first clutch connecting rod 512, and a transmission crank 513 fixed to the right end of the thread-cutting shaft 41 in the thread-cutting unit 40. The thread-cutting shaft 41 is rotatably supported in the modular sewing machine base plate. The upper section of the first clutch connecting rod 512 has a free-stroke groove 5121 extending along the length direction of the first clutch connecting rod 512. The fourth clutch ball 511 is located in the free-stroke groove 5121 of the first clutch connecting rod 512, and the two slide in cooperation. The fourth clutch ball 511 and the free-stroke groove 5121 of the first clutch connecting rod 512 form a sliding pair. The lower end of the first clutch connecting rod 512 is hinged to the transmission crank 513. The lifting tooth thread-cutting drive source 10 is fixed to the modular sewing machine base plate.

[0175] like Figure 23 As shown, the starting and ending points of the tooth-lifting zone X1 of the tooth-lifting shearing drive source 10 are respectively angles. and The starting and ending points of the wire-cutting zone X2 of the wire-lifting and wire-cutting drive source 10 are respectively angles. and In this embodiment, That is, the end point of the lifting zone X1 coincides with the starting point of the thread-cutting zone X2. During sewing operations, the modular sewing machine's lifting and thread-cutting drive source 10 oscillates back and forth within a certain angle range within the lifting zone X1. During this process, such as... Figure 25 As shown, the fourth clutch ball 511 slides back and forth in the idle stroke groove 5121, performing the idle stroke action. Under the action of the fourth clutch ball 511, the first clutch linkage 512 oscillates back and forth around the hinge center between the first clutch linkage 512 and the transmission crank 513, thus not driving the transmission crank 513 to rotate. That is, there is no power transmission between the first clutch linkage 512 and the transmission crank 513, and the transmission crank 513 and the thread cutting shaft 41 do not rotate, and the thread cutting unit 40 does not operate. When the modular sewing machine needs to cut the thread, the lifting tooth thread cutting drive source 10 rotates from the lifting tooth area X1 in the positive direction to the thread cutting area X2. The positive direction is... Figure 23 In the clockwise direction in the view, during this process, such as Figure 27 As shown, the fourth clutch ball 511 slides upward along the idle stroke groove 5121 and abuts against the upper end of the idle stroke groove 5121. Then, the second clutch crank 510 drives the first clutch linkage 512 to move through the fourth clutch ball 511, so that there is power transmission between the first clutch linkage 512 and the transmission crank 513, which in turn drives the transmission crank 513 and the wire cutting shaft 41 to rotate, driving the wire cutting unit 40 to perform the wire cutting action and realize automatic wire cutting.

[0176] like Figure 20 As shown, the lifting unit 30 has a lifting shaft 31 parallel to the thread-cutting shaft 41 and rotatably supported in the modular sewing machine base plate. The motor shaft of the lifting and thread-cutting drive source 10 is connected to the right end of the lifting shaft 31 via a coupling, and the lifting and thread-cutting drive source 10 directly drives the lifting shaft 31 to rotate. The second clutch crank 510 is fixed to the motor shaft of the lifting and thread-cutting drive source 10 by screws, so the lifting and thread-cutting drive source 10 directly drives the second clutch crank 510 to rotate; or, the second clutch crank 510 is fixed to the lifting shaft 31 by screws, so the lifting and thread-cutting drive source 10 drives the second clutch crank 510 to rotate via the lifting shaft 31.

[0177] like Figure 20 As shown, the tooth lifting unit 30 also includes a tooth lifting eccentric crank 32, a tooth lifting connecting rod 33, and a tooth lifting pin 34 fixed to the left end of the tooth lifting shaft 31. One end of the tooth lifting connecting rod 33 is rotatably mounted on the eccentric part of the tooth lifting eccentric crank 32 via a bearing, and the other end of the tooth lifting connecting rod 33 is hinged to the tooth lifting connection part 21 of the tooth frame 20 via the tooth lifting pin 34. When the tooth lifting and wire cutting drive source 10 drives the tooth lifting shaft 31 and the tooth lifting eccentric crank 32 to swing back and forth within a certain angle range in the tooth lifting area X1, the tooth lifting connecting rod 33 drives the tooth lifting connection part 21 of the tooth frame 20 to move up and down reciprocally, thereby driving the feed tooth 70 to perform the up and down tooth lifting action.

[0178] In this embodiment, the tooth-lifting and wire-cutting drive source 10 outputs an angle. At that time, the modular sewing machine has a minimum effective tooth lifting height. The tooth lifting and thread cutting drive source 10 outputs an angle... and At that time, the fourth clutch ball 511 just moves to the end of the upper groove of the idle stroke groove 5121. At this time, if Figure 24 As shown, the eccentric crank 32 and the lifting rod 33 are collinear, meaning the center of the lifting shaft 31, the center of the eccentric part of the lifting crank 32, and the center of the lifting pin 34 (i.e., the hinge center of the lifting rod 33 and the lifting connection part 21 of the feed dog 20) are collinear. The feed dog 70 is in its extreme position, and the feed dog 70 protrudes upwards from the needle plate to its maximum distance, giving the modular sewing machine its maximum effective lifting height. Specifically, the lifting thread cutting drive source 10 outputs an angle... At this time, the modular sewing machine has a negative feed dog height, which corresponds to the feed dog 70 being below the needle plate. That is, the negative feed dog height at or before this moment. The feed dog lifting and thread cutting drive source 10, through the feed dog lifting unit 30, prevents the feed dog 70 of the modular sewing machine from protruding from the needle plate, causing the feed dog 70 to sink below the needle plate. This achieves downward feeding during thread cutting, preventing the feed dog 70 from pushing the fabric upwards. This shortens the distance between the fabric and the thread cutting engagement point in the thread cutting unit 40, reducing the length of the thread end remaining on the fabric after cutting and stably achieving a short thread cutting effect. Therefore, the feed dog lifting and thread cutting drive source 10 starts from the beginning of the feed dog lifting area X1. Rotate in the positive direction to the end point of the tooth lifting zone X1. During the process, the lifting height of the feed dog 70 gradually increases; when the lifting wire shearing drive source 10 operates within the lifting zone X1, the postures of the lifting eccentric crank 32 and the lifting connecting rod 33 are as follows: Figure 26 As shown. The wire-lifting and wire-cutting drive source 10 starts from the beginning of the wire-cutting zone X2. Rotate in the positive direction to the end of the shearing zone X2. During the process, the lifting height of the feed dog 70 gradually decreases; when the lifting and shearing drive source 10 operates within the shearing zone X2, the postures of the lifting eccentric crank 32 and the lifting connecting rod 33 are as follows: Figure 28 As shown.

[0179] Furthermore, the wire cutting unit 40 can adopt a single-moving blade structure or a double-moving blade structure, thus giving the wire cutting unit 40 the following two embodiments.

[0180] Example 1 of the wire-cutting unit 40 Figure 21As shown, the single-moving-blade thread-cutting unit 40 also includes a thread-cutting crank 44 fixed to the left end of the thread-cutting shaft 41, a thread-cutting connecting rod 45, a moving blade holder 46, a moving blade 47 fixed on the moving blade holder 46, a fixed blade 48 fixed on the base plate of the modular sewing machine, and a return torsion spring 417 sleeved around the outer periphery of the thread-cutting shaft 41. The two ends of the thread-cutting connecting rod 45 are hinged to the thread-cutting crank 44 and the moving blade holder 46, respectively. The two ends of the return torsion spring 417 are connected to the thread-cutting crank 44 and the base plate of the modular sewing machine, respectively. The lifting-tooth thread-cutting drive source 10 starts from the starting point of the thread-cutting zone X2. Rotate in the positive direction to the end of the shearing zone X2. During the process, the thread cutting shaft 41 drives the thread cutting crank 44 to rotate, which in turn drives the moving blade holder 46 to rotate around the lower shaft 82 via the thread cutting connecting rod 45, causing the moving blade 47 to rotate towards the fixed blade 48 until the two engage and cut the thread. After the thread cutting is completed, the reset torsion spring 417 causes the thread cutting crank 44 to reverse and reset, thereby resetting all components in the thread cutting unit 40.

[0181] Example 2 of the wire-cutting unit 40 Figure 22 As shown, the double-moving-blade thread-cutting unit 40 also includes a thread-cutting fork crank 49 fixed to the left end of the thread-cutting shaft 41, a thread-cutting connecting rod 45, a main blade holder 410, an active blade 411 fixed to the main blade holder 410, an auxiliary blade holder 412, auxiliary moving blades 413 fixed to the auxiliary blade holder 412, a thread-cutting transmission pin 414, and a return torsion spring 417 sleeved on the outer periphery of the thread-cutting shaft 41. The thread-cutting fork crank 49 has a fork arm portion, and the thread-cutting transmission pin 414 is located in the fork of the fork arm portion, with the two slidingly engaged. The thread-cutting transmission pin 414 and the fork arm portion of the thread-cutting fork crank 49 form a sliding pair. The two ends of the thread-cutting connecting rod 45 are respectively hinged to the thread-cutting fork crank 49 and the main blade holder 410. The two ends of the return torsion spring 417 are respectively connected to the thread-cutting fork crank 49 and the modular sewing machine base plate. The lifting-tooth thread-cutting drive source 10 starts from the starting point of the thread-cutting zone X2. Rotate in the positive direction to the end of the shearing zone X2. During the process, the thread cutting shaft 41 drives the thread cutting fork crank 49 to rotate, which drives the main blade holder 410 and the auxiliary blade holder 412 to rotate in opposite directions along the lower shaft 82, so that the active blade 411 and the auxiliary moving blade 413 rotate in opposite directions until they bite together to cut the thread; after the thread cutting is completed, the reset torsion spring 417 causes the thread cutting fork crank 49 to reverse and reset, thereby resetting the components in the thread cutting unit 40.

[0182] Example 4 of the tooth-lifting and wire-cutting module

[0183] like Figure 29As shown, the clutch unit 50 includes a fifth clutch cam 514 driven to rotate by the thread-cutting drive source 10, a second clutch lever 515 with a fixed rotation fulcrum, a fifth clutch ball 516 rotatably mounted on the rear end of the second clutch lever 515, and a second clutch connecting rod 517. The second clutch lever 515 is hinged to the modular sewing machine base plate by left and right extending pins, and the hinge point between the second clutch lever 515 and the modular sewing machine base plate constitutes the fixed rotation fulcrum of the second clutch lever 515. One end of the second clutch connecting rod 517 is hinged to the front end of the second clutch lever 515, and the other end of the second clutch connecting rod 517 is connected to the thread-cutting unit 40 for transmission.

[0184] like Figure 36a or Figure 36b or Figure 36c As shown, the starting and ending points of the tooth-lifting zone X1 of the tooth-lifting shearing drive source 10 are respectively angles. and The starting and ending points of the wire-cutting zone X2 of the wire-lifting and wire-cutting drive source 10 are respectively angles. and In this embodiment, When the modular sewing machine is performing sewing operations, the tooth-lifting and thread-cutting drive source 10 oscillates back and forth within a certain angle range in the tooth-lifting zone X1. During this process, there is no power transmission between the fifth clutch cam 514 and the fifth clutch ball 516, so the fifth clutch cam 514 will not push the second clutch lever 515 to rotate, and the thread-cutting unit 40 will not operate. When the modular sewing machine needs to cut the thread, the tooth-lifting and thread-cutting drive source 10 rotates from the tooth-lifting zone X1 in the positive direction to the thread-cutting zone X2, which is also the positive direction. Figure 36a or Figure 36b or Figure 36c In the counter-clockwise direction, the lifting tooth shearing drive source 10 starts from the beginning of the shearing zone X2. Turn forward to the end of the wire-cutting zone X2. During this process, there is a power transmission between the fifth clutch cam 514 and the fifth clutch ball 516. The fifth clutch cam 514 pushes the second clutch lever 515 to rotate around its fixed rotation fulcrum through the fifth clutch ball 516, and then drives the wire cutting unit 40 to perform the wire cutting action through the second clutch linkage 517 to achieve automatic wire cutting.

[0185] Preferably, such as Figure 30 As shown, the fifth clutch cam 514 is fixed to the motor shaft of the wire-lifting shear drive source 10 by screws, and the wire-lifting shear drive source 10 directly drives the fifth clutch cam 514 to rotate. Figure 32 As shown, the outer circumferential surface of the fifth clutch cam 514 is provided with a variable diameter section; when the tooth-lifting shearing drive source 10 operates within the tooth-lifting zone X1, as... Figure 33a and Figure 33bAs shown, the fifth clutch ball 516 and the fifth clutch cam 514 do not contact each other and are separated, so there is no power transmission between the fifth clutch ball 516 and the fifth clutch cam 514, and the wire cutting unit 40 does not operate; when the lifting wire cutting drive source 10 operates in the wire cutting area X2, as Figure 34 As shown, the fifth clutch ball 516 contacts the variable-diameter section of the fifth clutch cam 514, enabling power transmission between the fifth clutch ball 516 and the fifth clutch cam 514, thus activating the wire cutting unit 40. Alternatively, in other embodiments, a constant-diameter section can be provided on the outer circumferential surface of the fifth clutch cam 514; when the wire lifting and cutting drive source 10 operates within the lifting area X1, no power transmission between the fifth clutch ball 516 and the fifth clutch cam 514 is achieved through the contact between the constant-diameter section of the fifth clutch ball 516 and the fifth clutch cam 514.

[0186] Furthermore, the preferred structure of the tooth lifting unit 30 is as follows: Figure 30 As shown, the tooth-lifting unit 30 includes a tooth-lifting shaft 31 rotatably supported in the modular sewing machine base plate, a primary transmission assembly connecting the motor shaft of the tooth-lifting thread-cutting drive source 10 and the tooth-lifting shaft 31, and a secondary transmission assembly connecting the tooth-lifting shaft 31 and the tooth-lifting connecting part 21 of the tooth holder 20. Therefore, in this embodiment, the tooth-lifting unit 30 adopts a two-stage transmission structure. More specifically, the primary transmission assembly includes a tooth-lifting eccentric wheel 35 fixed to the motor shaft of the tooth-lifting thread-cutting drive source 10 by screws, a primary tooth-lifting connecting rod 36, and a primary tooth-lifting crank 37 fixed to the right end of the tooth-lifting shaft 31. One end of the primary tooth-lifting connecting rod 36 is rotatably mounted on the eccentric part of the tooth-lifting eccentric wheel 35 through a bearing, and the other end of the primary tooth-lifting connecting rod 36 is hinged to the primary tooth-lifting crank 37. The secondary transmission assembly includes a secondary lifting crank 38 fixed to the left end of the lifting shaft 31 and a secondary lifting connecting rod 39. The two ends of the secondary lifting connecting rod 39 are hinged to the secondary lifting crank 38 and the lifting connection portion 21 of the tooth frame 20, respectively. The primary lifting crank 37 and the secondary lifting crank 38 are offset from each other at a certain relative angle in the circumferential direction of the lifting shaft 31. Preferably, the lifting eccentric wheel 35 is located on the left side of the fifth clutch cam 514. The lifting eccentric wheel 35 and the fifth clutch cam 514 can be two independent cams or combined into an integral cam component. Figure 30 and Figure 32 In the view shown, the tooth-lifting eccentric wheel 35 and the fifth clutch cam 514 are combined into a single integral cam component.

[0187] Furthermore, when the wire-lifting and wire-cutting drive source 10 operates to the end point of the wire-cutting zone X2... The preceding (including the lifting wire cutting drive source 10 operating to the end point of the wire cutting zone X2) (At that time), the lifting tooth cutting drive source 10 prevents the feed dog 70 of the modular sewing machine from emerging from the needle plate through the lifting tooth unit 30. That is, the feed dog 70 sinks to the bottom of the needle plate, realizing the downward feeding during thread cutting. The feed dog 70 will not push the fabric upward, which can shorten the distance between the fabric and the thread cutting engagement point in the thread cutting unit 40, shorten the length of the thread end remaining on the fabric after cutting, and stably achieve the effect of cutting short thread ends.

[0188] Furthermore, such as Figure 36a or Figure 36b or Figure 36c As shown, the output angle of the tooth-lifting and wire-cutting drive source 10 is... At that time, the modular sewing machine has a minimum effective tooth lifting height; the tooth lifting and thread cutting drive source 10 outputs an angle. At that time, the modular sewing machine has the maximum effective lifting height; the lifting thread cutting drive source 10 starts from the beginning of the lifting zone X1. Rotate in the positive direction to the end point of the tooth lifting zone X1. During the process, the effective lifting height of the sewing machine gradually increases. Additionally, the lifting and thread-cutting drive source 10 rotates from the lifting zone X1 in the positive direction to the end point of the thread-cutting zone X2. During this process, the tooth-lifting wire-cutting drive source 10 will output an angle. At this time, as Figure 35 As shown, the eccentric part of the lifting eccentric wheel 35 is collinear with the first-stage lifting connecting rod 36. That is, the center of the motor shaft of the lifting thread cutting drive source 10, the center of the eccentric part of the lifting eccentric wheel 35, and the hinge center of the first-stage lifting connecting rod 36 and the first-stage lifting crank 37 are collinear. At this time, the feed dog 70 is in the extreme position, and the distance it protrudes upward from the needle plate is the maximum. In particular, the angle of the lifting thread cutting drive source 10... It must be smaller than the end point of the cut line area X2. To ensure the wire cutting is achieved during the cutting process, the angle of the wire cutting drive source 10 is adjusted accordingly. The following situations are possible: 1. For example Figure 36a As shown, II. Figure 36b As shown, III. Figure 36c As shown, Thus, during the thread cutting process, the height of the feed dog 70 changes as follows: it gradually increases from the current effective height to the corresponding height. The maximum effective tooth lifting height of the angle is gradually increased to the corresponding value. The maximum tooth lift height at the angle, then gradually decreasing to the corresponding... The negative angle of the feed dog height corresponds to the feed dog being 70 degrees below the needle plate.

[0189] Furthermore, the wire cutting unit 40 can adopt a single-moving blade structure or a double-moving blade structure; in this embodiment, the wire cutting unit 40 adopts a double-moving blade structure. For example... Figure 31 As shown, the double-moving-blade thread-cutting unit 40 includes a thread-cutting fork crank 49 with a fixed rotation fulcrum, a thread-cutting connecting rod 45, a main blade holder 410, an active blade 411 fixed on the main blade holder 410, an auxiliary blade holder 412, an auxiliary moving blade 413 fixed on the auxiliary blade holder 412, and a thread-cutting transmission pin 414. The thread-cutting fork crank 49 is rotatably mounted on the modular sewing machine base plate by a pin. The thread-cutting fork crank 49 has a fork arm. The second clutch connecting rod 517, the fork arm of the thread-cutting fork crank 49, and the auxiliary blade holder 412 are coaxially hinged by the thread-cutting transmission pin 414. The thread-cutting transmission pin 414 is located in the fork of the fork arm, and the two are in sliding engagement. The two ends of the thread-cutting connecting rod 45 are respectively hinged to the thread-cutting fork crank 49 and the main blade holder 410. The lifting-tooth thread-cutting drive source 10 starts from the starting point of the thread-cutting zone X2. Rotate in the positive direction to the end of the shearing zone X2. During the process, the fifth clutch cam 514 drives the second clutch lever 515 to rotate through the fifth clutch ball 516. The second clutch lever 515 drives the thread cutting fork crank 49 and the auxiliary blade holder 412 to rotate through the second clutch connecting rod 517. The thread cutting fork crank 49 drives the main blade holder 410 to rotate through the thread cutting connecting rod 45, so that the main blade holder 410 and the auxiliary blade holder 412 rotate towards each other along the lower shaft 82, so that the active blade 411 and the auxiliary moving blade 413 rotate towards each other until they bite together to cut the thread.

[0190] Furthermore, such as Figure 29 As shown, the thread-cutting module also includes a reset torsion spring 417 sleeved at the fixed rotation fulcrum of the second clutch lever 515, a stop pin 120 fixed on the second clutch lever 515, and a limiting block 130 fixed on the modular sewing machine base plate. The two ends of the reset torsion spring 417 are connected to the second clutch lever 515 and the modular sewing machine base plate, respectively. After thread cutting, the thread-cutting drive source 10 rotates in the opposite direction to reset, and the spring force of the reset torsion spring 417 causes the second clutch lever 515 to reverse and reset until the stop pin 120 abuts against the limiting block 130. The limiting block 130 restricts the second clutch lever 515 to its initial position, thereby resetting the components in the thread-cutting unit 40. Additionally, as... Figure 31 As shown, the second clutch lever 515 is equipped with a forced reset arm 511; as Figure 32As shown, the fifth clutch cam 514 is provided with a forced reset protrusion 5141. When a reset failure occurs after the wire cutting is completed, the tooth lifting eccentric wheel 35 and the fifth clutch cam 514 rotate in the opposite direction with the tooth lifting wire cutting drive source 10, which drives the forced reset protrusion 5141 to rotate in the opposite direction as well. Then, the forced reset protrusion 5141 gradually approaches the forced reset arm 511 on the second clutch lever 515. After the forced reset protrusion 5141 abuts against the forced reset arm 511, it will push the second clutch lever 515 to rotate in the opposite direction to perform forced reset, thus avoiding the failure of the active blade 411 and the auxiliary moving blade 413 to be stuck by the wire and unable to reset smoothly.

[0191] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0192] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A thread-cutting module for a modular sewing machine, characterized in that: The modular sewing machine includes a feeding module (60) connected to a feeding connection (22) at one end of the toother (20) and a feeding tooth (70) fixed on the toother (20). The tooth-lifting and thread-cutting module includes a tooth-lifting and thread-cutting drive source (10), a tooth-lifting unit (30) connected to a tooth-lifting connection (21) at one end of the toother (20), a thread-cutting unit (40), and a clutch unit (50). The tooth-lifting and thread-cutting drive source (10) is independent of other drive sources in the modular sewing machine. The output end of the tooth-lifting and thread-cutting drive source (10) is connected to the tooth-lifting unit (30). The clutch unit (50) is connected between the output end of the tooth-lifting and thread-cutting drive source (10) and the thread-cutting unit (40), or between the tooth-lifting unit (30) and the thread-cutting unit (40). The operating range of the tooth lifting and wire cutting drive source (10) includes an independent tooth lifting area and a wire cutting area; when the tooth lifting and wire cutting drive source (10) operates in the tooth lifting area, the clutch unit (50) is in the disengaged state of the transmission chain; when the tooth lifting and wire cutting drive source (10) operates in the wire cutting area, the clutch unit (50) is in the engaged state of the transmission chain. When the modular sewing machine is performing sewing operations, the lifting tooth and thread cutting drive source (10) swings back and forth within a certain angle range in the lifting tooth area. This angle range corresponds to the set lifting tooth height of the modular sewing machine. During this process, the lifting tooth unit (30) drives the tooth frame (20) and the feed tooth (70) to reciprocate downwards and perform the lifting tooth action. The feeding module (60) drives the tooth frame (20) and the feed tooth (70) to reciprocate back and forth and perform the feeding action. However, the clutch unit (50) is in the state of disengaged transmission chain, so that the output torque of the lifting tooth and thread cutting drive source (10) will not be transmitted to the thread cutting unit (40).

2. The tooth-lifting and wire-cutting module according to claim 1, characterized in that: The clutch unit (50) includes a first clutch cam (51) driven to rotate by a thread-cutting drive source (10), a second clutch cam (52) fixed on the thread-cutting shaft (41) in the thread-cutting unit (40), and a first clutch ball (53). The first clutch ball (53) is rotatably mounted on the first clutch cam (51) and can contact the second clutch cam (52), or the first clutch ball (53) is rotatably mounted on the second clutch cam (52) and can contact the first clutch cam (51). The thread-cutting shaft (41) is rotatably supported in the modular sewing machine base plate.

3. The tooth-lifting and wire-cutting module according to claim 1, characterized in that: The clutch unit (50) includes a third clutch cam (54) driven to rotate by a wire-cutting drive source (10), a first clutch lever (55) having a fixed rotation fulcrum, a second clutch ball (56) rotatably mounted on the first clutch lever (55), a first clutch crank (57) fixed on the wire-cutting shaft (41) in the wire-cutting unit (40), a third clutch ball (58) rotatably mounted on the first clutch crank (57), and a mechanism fixed to the modular seam. The fourth clutch cam (59) on the lower shaft (82) of the sewing machine, the second clutch ball (56) can abut against the third clutch cam (54), the third clutch ball (58) can abut against the fourth clutch cam (59); the thread cutting shaft (41) is rotatably and movablely supported in the modular sewing machine base plate, the first clutch crank (57) is provided with a push protrusion (571), and the first clutch lever (55) abuts against the push protrusion (571).

4. The tooth-lifting and wire-cutting module according to claim 3, characterized in that: The thread cutting unit (40) further includes a thread cutting slider (42) rotatably mounted on a first clutch crank (57), a thread cutting crank shaft (43), a thread cutting crank (44), a thread cutting connecting rod (45), a moving knife holder (46), a moving knife (47) fixed on the moving knife holder (46), and a fixed knife (48) fixed on the base plate of the modular sewing machine. The thread cutting crank shaft (43) includes a transmission shaft part parallel to the thread cutting shaft (41) and rotatably supported in the base plate of the modular sewing machine, and a crank part integrally provided at one end of the transmission shaft part. The crank part has a thread cutting groove (431) that slides with the thread cutting slider (42). The thread cutting crank (44) is fixed at the other end of the transmission shaft part. The two ends of the thread cutting connecting rod (45) are respectively hinged to the thread cutting crank (44) and the moving knife holder (46).

5. The tooth-lifting and wire-cutting module according to claim 3, characterized in that: The wire cutting unit (40) further includes a wire cutting slider (42) rotatably mounted on a first clutch crank (57), a wire cutting crank shaft (43), a wire cutting fork crank (49), a wire cutting connecting rod (45), a main blade holder (410), an active blade (411) fixed on the main blade holder (410), an auxiliary blade holder (412), and auxiliary moving blades (413) and wire cutting transmission pins (414) all fixed on the auxiliary blade holder (412). The wire cutting crank shaft (43) includes a rotatable support parallel to the wire cutting shaft (41). The transmission shaft is supported in the base plate of the modular sewing machine, and the crank is integrally provided at one end of the transmission shaft. The crank has a thread cutting groove (431) that slides with the thread cutting slider (42). The thread cutting fork crank (49) is fixed at the other end of the transmission shaft. The thread cutting fork crank (49) has a fork arm. The thread cutting transmission pin (414) is located in the fork of the fork arm and the two slide with each other. The two ends of the thread cutting connecting rod (45) are respectively hinged to the thread cutting fork crank (49) and the main blade holder (410).

6. The tooth-lifting and wire-cutting module according to claim 1, characterized in that: The clutch unit (50) includes a second clutch crank (510) driven to rotate by a thread-cutting drive source (10), a fourth clutch ball (511) rotatably mounted on the second clutch crank (510), a first clutch connecting rod (512), and a transmission crank (513) fixed on the thread-cutting shaft (41) in the thread-cutting unit (40). The first clutch connecting rod (512) has a free-stroke groove (5121) extending along its length direction. The fourth clutch ball (511) is located in the free-stroke groove (5121) of the first clutch connecting rod (512), and the two are slidably engaged. The first clutch connecting rod (512) is hinged to the transmission crank (513). The thread-cutting shaft (41) is rotatably supported in the modular sewing machine base plate.

7. The tooth-lifting and wire-cutting module according to claim 2, 3, or 6, characterized in that: The tooth-lifting and thread-cutting drive source (10) is a motor. The tooth-lifting unit (30) includes a tooth-lifting shaft (31) rotatably supported in the modular sewing machine base plate, a tooth-lifting eccentric crank (32) fixed on the tooth-lifting shaft (31), a tooth-lifting connecting rod (33), and a tooth-lifting pin (34). The tooth-lifting shaft (31) is fixedly connected to the motor shaft of the tooth-lifting and thread-cutting drive source (10). One end of the tooth-lifting connecting rod (33) is rotatably fitted on the eccentric part of the tooth-lifting eccentric crank (32). The other end of the tooth-lifting connecting rod (33) is hinged to the tooth-lifting connection part (21) of the tooth frame (20) through the tooth-lifting pin (34).

8. The tooth-lifting and wire-cutting module according to claim 2 or 6, characterized in that: The thread cutting unit (40) also includes a thread cutting crank (44) fixed on the thread cutting shaft (41), a thread cutting connecting rod (45), a moving knife holder (46), a moving knife (47) fixed on the moving knife holder (46), and a fixed knife (48) fixed on the bottom plate of the modular sewing machine. The two ends of the thread cutting connecting rod (45) are respectively hinged to the thread cutting crank (44) and the moving knife holder (46).

9. The tooth-lifting and wire-cutting module according to claim 2 or 6, characterized in that: The wire cutting unit (40) also includes a wire cutting fork crank (49) fixed on the wire cutting shaft (41), a wire cutting connecting rod (45), a main blade holder (410), an active blade (411) fixed on the main blade holder (410), an auxiliary blade holder (412), and an auxiliary moving blade (413) and a wire cutting transmission pin (414) both fixed on the auxiliary blade holder (412). The wire cutting fork crank (49) has a fork arm, and the wire cutting transmission pin (414) is located in the fork of the fork arm, and the two are slidably engaged. The two ends of the wire cutting connecting rod (45) are respectively hinged to the wire cutting fork crank (49) and the main blade holder (410).

10. The tooth-lifting and wire-cutting module according to claim 2 or 6, characterized in that: The wire cutting unit also includes a wire cutting crank (44) fixed on the wire cutting shaft (41), a wire cutting main connecting rod (415), a main blade holder (410), an active blade (411) fixed on the main blade holder (410), a wire cutting auxiliary connecting rod (416), an auxiliary blade holder (412), and an auxiliary moving blade (413) fixed on the auxiliary blade holder (412). The outer periphery of the wire cutting crank (44) is provided with a first wire cutting arm (441) and a second wire cutting arm (442) that are circumferentially staggered. The two ends of the wire cutting main connecting rod (415) are respectively hinged to the first wire cutting arm (441) and the main blade holder (410), and the two ends of the wire cutting auxiliary connecting rod (416) are respectively hinged to the second wire cutting arm (442) and the auxiliary blade holder (412).

11. The tooth-lifting and wire-cutting module according to claim 1, characterized in that: The clutch unit (50) includes a fifth clutch cam (514) driven to rotate by a wire-cutting drive source (10), a second clutch lever (515) with a fixed rotation fulcrum, a fifth clutch ball (516) rotatably mounted on the second clutch lever (515), and a second clutch link (517) with one end hinged to the second clutch lever (515), the other end of which is connected to the wire-cutting unit (40) for transmission.

12. The tooth-lifting and wire-cutting module according to claim 11, characterized in that: The lifting and thread-cutting drive source (10) is a motor. The lifting unit (30) includes a lifting shaft (31) rotatably supported in the modular sewing machine base plate, a primary transmission assembly connecting the motor shaft of the lifting and thread-cutting drive source (10) and the lifting shaft (31), and a secondary transmission assembly connecting the lifting shaft (31) and the lifting connecting part (21) of the tooth frame (20). The primary transmission assembly includes a lifting eccentric wheel (35) fixed on the motor shaft of the lifting and thread-cutting drive source (10), a primary lifting connecting rod (36), and a fixed... A primary tooth-lifting crank (37) is fixed on the tooth-lifting shaft (31). One end of the primary tooth-lifting connecting rod (36) is rotatably mounted on the eccentric part of the tooth-lifting eccentric wheel (35). The other end of the primary tooth-lifting connecting rod (36) is hinged to the primary tooth-lifting crank (37). The secondary transmission assembly includes a secondary tooth-lifting crank (38) fixed on the tooth-lifting shaft (31) and a secondary tooth-lifting connecting rod (39). The two ends of the secondary tooth-lifting connecting rod (39) are respectively hinged to the secondary tooth-lifting crank (38) and the tooth-lifting connection part (21) of the tooth frame (20).

13. The tooth-lifting and wire-cutting module according to claim 11, characterized in that: The wire cutting unit (40) includes a wire cutting fork crank (49) with a fixed rotation fulcrum, a wire cutting connecting rod (45), a main blade holder (410), an active blade (411) fixed on the main blade holder (410), an auxiliary blade holder (412), an auxiliary moving blade (413) fixed on the auxiliary blade holder (412), and a wire cutting transmission pin (414). The wire cutting fork crank (49) has a fork arm. The second clutch connecting rod (517), the fork arm of the wire cutting fork crank (49), and the auxiliary blade holder (412) are coaxially hinged through the wire cutting transmission pin (414). The wire cutting transmission pin (414) is located in the fork of the fork arm and the two are slidably engaged. The two ends of the wire cutting connecting rod (45) are respectively hinged to the wire cutting fork crank (49) and the main blade holder (410).

14. The tooth-lifting and wire-cutting module according to claim 1, characterized in that: Before the lifting tooth thread cutting drive source (10) reaches the end of the thread cutting area, the lifting tooth thread cutting drive source (10) prevents the feed dog (70) of the modular sewing machine from emerging from the needle plate through the lifting tooth unit (30).

15. A modular sewing machine, characterized in that: The modular sewing machine is equipped with a thread-cutting module as described in any one of claims 1-14.

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