A sewing machine which feeds and cuts thread by using the same driving source

Abstract

The application provides a sewing machine which uses the same driving source to feed and cut thread, comprising a feeding and thread cutting driving source, a feeding mechanism and a thread cutting mechanism; the feeding mechanism comprises a rack, feeding teeth, a driving crank which is driven to rotate by the feeding and thread cutting driving source and a feeding transmission unit; the thread cutting mechanism comprises a movable cutter, a thread cutting arm which extends from the driving crank, a thread cutting shaft, a thread cutting clutch assembly and a thread cutting transmission assembly which is transmissionally connected between the thread cutting shaft and the cutter, the thread cutting clutch assembly comprises thread cutting balls which are rotatably installed on the thread cutting arm and a thread cutting driving part which is fixed on the thread cutting shaft. The application uses the same feeding and thread cutting driving source to drive the feeding mechanism and the thread cutting mechanism. When cutting thread, the feeding and thread cutting driving source drives the cutter to move through the driving crank, the engaged thread cutting clutch assembly and the thread cutting transmission assembly in sequence, so as to realize thread cutting, and the thread cutting power is not dependent on other driving sources in the sewing machine, thereby simplifying the structure and shortening the transmission chain.

Description

Technical Field

[0001] This invention relates to the field of sewing machine technology, and in particular to a sewing machine that uses the same drive source for feeding and thread cutting. 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] For example, the drive mechanism of a flat sewing machine disclosed in Chinese Utility Model Patent Application No. 201220297729.6 drives the lifting tooth shaft and the feeding shaft through a main shaft (i.e., the upper shaft). The main shaft is driven by a main motor. The lifting tooth shaft drives the tooth holder and the feeding tooth to move up and down reciprocally through a set of lifting tooth components to perform the lifting action. The feeding shaft drives the tooth holder and the feeding tooth to move back and forth reciprocally through a set of feeding components to perform the feeding action. At the same time, the main shaft also drives the lower shaft to rotate through a set of synchronous belt pulley mechanisms. The lower shaft drives the rotary hook mechanism to rotate and perform the thread hooking action. Furthermore, the sewing machine can also be equipped with a thread cutting mechanism. For example, an automatic thread cutting mechanism disclosed in Chinese Invention Patent Application No. 201710215982.X, when thread cutting is required, the thread cutting drive source is activated, causing the thread cutting ball to contact the thread cutting cam fixed on the lower shaft. Then, the rotation of the lower shaft drives the thread cutting component to rotate and perform the automatic thread cutting action. Clearly, the feeding mechanism, lifting mechanism, and thread cutting mechanism of this sewing machine are relatively complex, with many parts, a long transmission chain, and a clutch component in the thread cutting mechanism to achieve the thread cutting action.

[0004] For example, Chinese invention patent application number 201210365288.3 discloses a sewing machine in which the lifting mechanism is driven by the main shaft of the sewing machine, the main shaft is driven by a main motor, the feeding mechanism is driven by a single feeding motor, and the clutch of the thread cutting mechanism is also driven by the same feeding motor. During thread cutting, after the feeding motor drives the transmission components in the thread cutting mechanism, the thread cutting assembly is still driven by the thread cutting cam on the lower shaft to perform the automatic thread cutting action. Clearly, this sewing machine structure is complex, especially given the use of a grooved cam structure, which is difficult to implement. Furthermore, during thread cutting, it still relies on the main motor driving the main shaft to rotate → the main shaft driving the lower shaft to rotate → the lower shaft driving the thread cutting cam to rotate, thus completing the thread cutting action.

[0005] For example, Chinese utility model patent application number 201520782770.6 discloses a thread-cutting and presser foot-lifting device for a sewing machine. A stepper motor drives both the thread-cutting and presser foot-lifting mechanisms through a complex system. However, because the final execution ends (moving and stationary blades) of the thread-cutting mechanism are located at the left end of the base plate, and the final execution end (presser foot) of the presser foot-lifting mechanism is located at the machine head, the span between the stepper motor and the moving blade, and between the stepper motor and the presser foot, is large. This results in a long overall transmission chain for the sewing machine, causing the stepper motor and transmission structure to occupy most of the installation space within the base plate, thus interfering with the arrangement and installation of other transmission structures in the sewing machine.

[0006] For example, Chinese utility model patent application number 202120273965.3 discloses a sewing machine with a positioning feed dog stop position. It uses a stepper motor to drive a swing seat to rotate, placing the swing seat at different position angles, with each angle corresponding to a different stitch length. Simultaneously, the stepper motor drives the thread-cutting fork wheel and other thread-cutting components via a thread-cutting crank wheel to perform the thread-cutting action. However, this sewing machine structure has a large number of parts, a long transmission chain, poor structural stability, and complex transmission mechanisms for stitch length adjustment and thread-cutting drive. Furthermore, it uses a slotted cam structure, which is difficult to implement.

[0007] In summary, existing sewing machines have the following problems: 1. Complex structure, resulting in poor stability and difficulty in implementation; 2. Long transmission chain, causing the transmission structure, including the stepper motor, to occupy most of the machine's installation space, interfering with the layout and installation of other structures; 3. Relatively simple function, the power of the thread cutting mechanism still depends on the main shaft, or in other words, it still depends on the main motor, and the power source configured in the thread cutting mechanism can only realize the switching of the thread cutting clutch. Summary of the Invention

[0008] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a sewing machine that uses the same drive source for feeding and cutting threads, wherein the drive source for feeding and cutting threads can independently drive feeding and cutting threads, so that the power source for cutting threads does not depend on other drive sources in the sewing machine.

[0009] To achieve the above objectives, the present invention provides a sewing machine that uses the same drive source for feeding and thread cutting, including a feeding and thread cutting drive source, a feeding mechanism, and a thread cutting mechanism;

[0010] The feeding mechanism includes a feeder frame, a feeder fixed on the feeder frame, a drive crank driven to rotate by a feed shearing drive source, and a feeding transmission unit. A feeder arm extends from the drive crank, and the feeding transmission unit is connected between the feeder arm and the feeder frame.

[0011] The wire cutting mechanism includes a movable blade, a wire cutting arm driven to rotate by a feeding wire cutting drive source, a wire cutting shaft rotatable about its own axis, a wire cutting clutch assembly, and a wire cutting transmission assembly connected between the wire cutting shaft and the movable blade. The wire cutting clutch assembly includes a wire cutting ball and a wire cutting drive component fixed on the wire cutting shaft. A wire cutting drive arm extends from the wire cutting drive component. The wire cutting ball is rotatably mounted on the wire cutting arm, and the wire cutting drive arm has a wire cutting groove surface; or, the wire cutting ball is rotatably mounted on the wire cutting drive arm, and the wire cutting arm has a wire cutting groove surface.

[0012] During the process of the feed and thread-cutting drive source driving the drive crank to rotate, the angle of the feed arm has an independent feed working area and a thread-cutting working area: when the feed arm operates in the feed working area, the sewing machine has an effective stitch pitch, and the thread-cutting ball is separated from the thread-cutting groove surface; when the feed arm operates in the thread-cutting working area, the thread-cutting ball is in contact with the thread-cutting groove surface.

[0013] Furthermore, the wire cutting mechanism is a single-moving-blade structure, and the wire cutting mechanism also includes a fixed blade. The wire cutting transmission assembly includes a wire cutting crank, a wire cutting connecting rod, and a rotatable moving blade holder, all fixed on the wire cutting shaft. The two ends of the wire cutting connecting rod are respectively hinged to the wire cutting crank and the moving blade holder, and the moving blade is fixed on the moving blade holder.

[0014] Furthermore, the wire-cutting mechanism also includes a reset torsion spring sleeved on the wire-cutting shaft, one end of which is fixed and the other end is connected to the wire-cutting crank.

[0015] Furthermore, the wire cutting mechanism is a single-moving-blade structure, and the wire cutting mechanism also includes a fixed blade. The wire cutting transmission assembly includes a wire cutting connecting arm, a wire cutting connecting rod, and a rotatable moving blade holder extending from the wire cutting drive component. The two ends of the wire cutting connecting rod are respectively hinged to the wire cutting connecting arm and the moving blade holder, and the moving blade is fixed on the moving blade holder.

[0016] Furthermore, the wire cutting mechanism also includes a reset torsion spring sleeved on the wire cutting shaft, one end of which is fixed and the other end is connected to the wire cutting connecting arm.

[0017] Furthermore, a reset arm extends from the wire-cutting drive component. The reset arm is circumferentially offset from the wire-cutting drive arm, and the forced reset surface on the reset arm can contact and engage with the wire-cutting ball.

[0018] Furthermore, the feeding transmission unit includes a feeding connecting rod, a feeding shaft that can rotate around its own axis, a feeding crank fixed to one end of the feeding shaft, and a toothed bracket seat fixed to the other end of the feeding shaft. The two ends of the feeding connecting rod are respectively rotatably connected to the feeding arm and the feeding crank, and the toothed bracket seat is connected to the feeding connection part of the toothed bracket. The effective length of the feeding arm is less than the effective length of the feeding connecting rod.

[0019] Furthermore, the feeding transmission unit includes a feeding link, a feeding shaft that can rotate around its own axis, a tooth holder fixed on the feeding shaft, and a feeding connecting arm fixedly connected to the tooth holder. The two ends of the feeding link are rotatably connected to the feeding arm and the feeding connecting arm, respectively. The tooth holder is connected to the feeding connecting part of the tooth holder. The effective length of the feeding arm is greater than the effective length of the feeding link.

[0020] Furthermore, the sewing machine also includes a tooth-lifting drive source and a tooth-lifting mechanism. The tooth-lifting drive source is the main motor of the sewing machine. The tooth-lifting mechanism includes a main shaft driven to rotate by the main motor, a tooth-lifting shaft parallel to the main shaft, a first tooth-lifting transmission assembly connected between the main shaft and the tooth-lifting shaft, and a second tooth-lifting transmission assembly connected between the tooth-lifting shaft and the tooth-lifting connection part of the tooth holder. The first tooth-lifting transmission assembly includes a tooth-lifting eccentric wheel fixed on the main shaft, a tooth-lifting crank fixed at one end of the tooth-lifting shaft, and a tooth-lifting connecting rod. One end of the tooth-lifting connecting rod is rotatably sleeved on the outer circumference of the tooth-lifting eccentric wheel, and the other end of the tooth-lifting connecting rod is hinged to the tooth-lifting crank. The second tooth-lifting transmission assembly includes a tooth-lifting fork-shaped crank fixed at the other end of the tooth-lifting shaft and a tooth-lifting slider hinged to the tooth-lifting connection part of the tooth holder. The tooth-lifting fork-shaped crank has a tooth-lifting groove that slides with the tooth-lifting slider.

[0021] Furthermore, the sewing machine also includes a tooth-lifting drive source and a tooth-lifting mechanism. The tooth-lifting drive source is the main motor of the sewing machine. The tooth-lifting mechanism includes a main shaft driven to rotate by the main motor, a tooth-lifting shaft parallel to the main shaft, a first tooth-lifting transmission assembly connected between the main shaft and the tooth-lifting shaft, and a second tooth-lifting transmission assembly connected between the tooth-lifting shaft and the tooth-lifting connection part of the tooth holder. The first tooth-lifting transmission assembly includes a driving pulley fixed on the main shaft, a driven pulley fixed at one end of the tooth-lifting shaft, and a transmission belt connected to the outer periphery of the driving pulley and the driven pulley. The second tooth-lifting transmission assembly includes a tooth-lifting eccentric wheel fixed at the other end of the tooth-lifting shaft and a tooth-lifting connecting rod. One end of the tooth-lifting connecting rod is rotatably sleeved on the outer periphery of the tooth-lifting eccentric wheel, and the other end of the tooth-lifting connecting rod is hinged to the tooth-lifting connection part of the tooth holder.

[0022] As described above, the sewing machine of the present invention, which uses the same drive source for feeding and thread cutting, has the following beneficial effects:

[0023] This application uses the same feeding and thread-cutting drive source to drive the feeding mechanism and the thread-cutting mechanism, thereby realizing feeding and thread cutting; and by setting a thread-cutting clutch component in the thread-cutting mechanism, the thread-cutting mechanism does not move during normal sewing feeding, ensuring that feeding and thread cutting do not interfere with each other; and, when cutting the thread, the feeding and thread-cutting drive source drives the moving blade to move through the drive crank, the engaged thread-cutting clutch component and the thread-cutting transmission component in sequence, thereby realizing thread cutting. That is, the power for thread cutting comes from the feeding and thread-cutting drive source, without relying on other drive sources in the sewing machine, thereby simplifying the structure and shortening the transmission chain. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the sewing machine in this application.

[0025] Figure 2 This is a structural diagram of the sewing machine in this application when equipped with a swing-type tooth-lifting mechanism.

[0026] Figure 3 This is a structural diagram of the sewing machine in this application when equipped with a rotary toother.

[0027] Figure 4 This is a schematic diagram of the structure of an embodiment of the independent feeding and wire cutting module in this application.

[0028] Figure 5 for Figure 4 The exploded view shows the integrated mounting base, which is omitted.

[0029] Figure 6 for Figure 4 The left view of the figure omits the integrated mounting base.

[0030] Figure 7 This is a schematic diagram of the distribution of the working area of ​​the feeding arm in Embodiment 1 of the independent feeding and cutting module.

[0031] Figure 8 This is a schematic diagram of the wire cutting clutch assembly in the disengaged state in Embodiment 1 of the independent feeding and wire cutting module.

[0032] Figure 9 This is a schematic diagram of the wire cutting clutch assembly in the engaged state in Embodiment 1 of the independent feeding and wire cutting module.

[0033] Figures 10a to 10d This is a schematic diagram of the four motion trajectories of the feed teeth in Embodiment 1 of the independent feeding and cutting module.

[0034] Figure 11 This is a schematic diagram showing the position of the feeding arm and the feeding connecting rod collinear in Embodiment 1 of the independent feeding and cutting module.

[0035] Figures 12a to 12cThis is a schematic diagram showing three distributions of the wire cutting work area of ​​the feeding arm in Embodiment 1 of the independent feeding and wire cutting module.

[0036] Figure 13 This is a schematic diagram of the structure of Embodiment 2 of the independent feeding and wire cutting module in this application.

[0037] Figure 14 for Figure 13 The left view.

[0038] Figure 15 This is a schematic diagram showing the connection between the module driver and the feeding mechanism in Embodiment 2 of the independent feeding and wire cutting module.

[0039] Figure 16 This is a schematic diagram showing the connection between the module driver and the wire cutting mechanism in Embodiment 2 of the independent feeding and wire cutting module.

[0040] Figure 17 This is a schematic diagram of the distribution of the working area of ​​the feeding arm in Embodiment 2 of the independent feeding and cutting module.

[0041] Figure 18 This is a schematic diagram of the wire cutting clutch assembly in the engaged state in Embodiment 2 of the independent feeding and wire cutting module.

[0042] Figures 19a to 19d This is a schematic diagram of the four motion trajectories of the feed teeth in Embodiment 2 of the independent feeding and cutting module.

[0043] Figure 20 This is a schematic diagram showing the position of the feeding arm and the feeding connecting rod collinear in Embodiment 2 of the independent feeding and wire cutting module.

[0044] Figures 21a to 21c This is a schematic diagram showing three distributions of the wire cutting work area of ​​the feeding arm in Embodiment 2 of the independent feeding and wire cutting module.

[0045] Component designation explanation

[0046] 10 Integrated mounting base

[0047] 101 Install motherboard

[0048] 102 Motor mounting plate

[0049] 103 Feeding Support Section

[0050] 104 Wire Cutting Support

[0051] 20 Module Driver Sources

[0052] 21 Drive motor

[0053] 30 Feeding mechanism

[0054] 31 Dental frame

[0055] 311 Feeding Connection Section

[0056] 312 Tooth-lifting connection

[0057] 32 feed dog

[0058] 33 Drive crank

[0059] 331 Feeding arm

[0060] 332 Wire Cutting Arm

[0061] 34 Feeding Link

[0062] 35 Feeding shaft

[0063] 36 Feed Crank

[0064] 37 Dental bracket

[0065] 371 Feeding Connecting Arm

[0066] 40 Wire cutting mechanism

[0067] 41. Cutting

[0068] 42 Thread cutter spool

[0069] 43 Wire-cutting ball bearing

[0070] 44 Wire cutting drive unit

[0071] 441 Wire Cutting Drive Arm

[0072] 442 Wire Cutting Connector Arm

[0073] 443 Reset Arm

[0074] 45 Fixed tool

[0075] 46 Wire-cutting crank

[0076] 47. Wire-cutting connecting rod

[0077] 48. Moving tool holder

[0078] 49. Return torsion spring

[0079] 50 Tooth Lifting Mechanism

[0080] 51 Spindle

[0081] 52 Tooth-lifting shaft

[0082] 53 Eccentric tooth lifting wheel

[0083] 54. Crank handle for lifting teeth

[0084] 55. Tooth-lifting linkage

[0085] 56. Lifting tooth fork-shaped crank

[0086] 57 Tooth-lifting slider

[0087] 58 Drive pulley

[0088] 59 Driven pulley

[0089] 510 Transmission Belt

[0090] 60 base plate Detailed Implementation

[0091] 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.

[0092] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and objectives of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and 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.

[0093] This application provides a sewing machine that uses the same drive source for feeding and thread trimming. For ease of description, in the following embodiments, the directions are defined as follows: the length direction of the sewing machine is defined as the left-right direction, and the direction towards the head of the sewing machine is the left direction, and the direction towards the tail of the sewing machine is the right direction. The left-right direction is also the axial direction of the main shaft 51 in the sewing machine; the height direction of the sewing machine is defined as the up-down direction, the width direction of the sewing machine is defined as the front-back direction, and the direction of fabric movement when the sewing machine is sewing forward is the front direction.

[0094] like Figure 1 ,as well as Figures 3 to 6 As shown, or as Figure 1 ,as well as Figures 13 to 16As shown, the sewing machine using the same drive source for feeding and thread cutting in this application includes a feeding and thread cutting drive source 20, a feeding mechanism 30, and a thread cutting mechanism 40. The feeding mechanism 30 includes a feed dog 31, a feed dog 32 fixed to the upper surface of the feed dog 31, a drive crank 33 driven to rotate by the feeding and thread cutting drive source 20, and a feeding transmission unit. The front end of the feed dog 31 is a feeding connection part 311, and the rear end of the feed dog 31 is a lifting connection part 312. A feed arm 331 extends from the drive crank 33, and the feeding transmission unit is connected between the feed arm 331 and the feed connection part 311 of the feed dog 31. The wire cutting mechanism 40 includes a movable blade 41, a wire cutting arm 332 driven to rotate by a feeding wire cutting drive source 20, a wire cutting shaft 42 rotatable about its own axis and extending left and right, a wire cutting clutch assembly, and a wire cutting transmission assembly connected between the wire cutting shaft 42 and the movable blade 41. The wire cutting clutch assembly includes a wire cutting ball 43 and a wire cutting drive member 44 fixed to the right end of the wire cutting shaft 42. A wire cutting drive arm 441 extends from the wire cutting drive member 44. The wire cutting ball 43 is rotatably mounted on the wire cutting arm 332, and the wire cutting drive arm 441 is provided with a wire cutting groove surface. Alternatively, the wire cutting ball 43 is rotatably mounted on the wire cutting drive arm 441, and the wire cutting arm 332 is provided with a wire cutting groove surface. In the following embodiment, taking the wire cutting ball 43 being rotatably mounted on the wire cutting arm 332 as an example, the wire cutting drive member 44 extends with a wire cutting drive arm 441.

[0095] Preferably, both the wire-cutting arm 332 and the drive crank 33 are driven to rotate by the wire-cutting drive source 20. In this case, the wire-cutting arm 332 and the drive crank 33 can be separate components, both fixed to the motor shaft of the module drive source 20 by screws; alternatively, the wire-cutting arm 332 can be fixed to the drive crank 33. In the following embodiments, the wire-cutting arm 332 extends integrally from the outer circumference of the drive crank 33.

[0096] During the process of the feed shearing drive source 20 driving the drive crank 33 to rotate, such as Figure 7 or Figure 17 As shown, the feeding arm 331 has an independent feeding working area X1 and a wire cutting working area X2. The two ends of the feeding working area X1 have angles of respectively and The angles at both ends of the wire-cutting work area X2 are respectively and Along the forward rotation direction of the drive motor 21 when the sewing machine cuts the thread, Thus, the angle range of the feeding working area X1 of the feeding arm 331 is... The angle range of the wire cutting working area X2 of the feeding arm 331 is: Furthermore, the feeding arm 331 also has an idle area X3 distributed between the feeding working area X1 and the wire cutting working area X2, and the angle range of the idle area X3 of the feeding arm 331 is as follows:

[0097] During normal sewing, the thread feed and thread trimming drive source 20 drives the drive crank 30 to rotate, and the feed arm 331 rotates together with the drive crank 30. When the thread feed and thread trimming drive source 20 drives the feed arm 331 of the drive crank 33 to operate within the feed working area X1, the feed arm 331 drives the feed dog 31 to move back and forth through the feed transmission unit, and the feed dog 32 moves back and forth synchronously with the feed dog 31 to perform the feeding action. The sewing machine has an effective stitch length, which includes a positive stitch length corresponding to the forward sewing state and a negative stitch length corresponding to the reverse sewing state; while the thread trimming ball 43 is separated from the thread trimming groove surface on the thread trimming drive arm 441, such as Figure 8 As shown, this keeps the wire-cutting clutch assembly in a disengaged state, thus preventing the transmission of force to the wire-cutting drive assembly, and therefore the wire-cutting mechanism 40 does not perform the wire-cutting action.

[0098] When the sewing machine needs to trim the thread, the feeding and trimming drive source 20 drives the feeding arm 331 to rotate clockwise from the current angle in the feeding work area X1 to the starting angle in the trimming work area X2. Then, continue rotating forward to the endpoint angle of the wire cutting work area X2. From the feed arm 331 Turning to During this process, when the feeding arm 331 is operating within the wire cutting working area X2, the wire cutting balls 43 gradually approach the wire cutting groove surface of the wire cutting drive arm 441 until they make contact, such as... Figure 9 or Figure 18 As shown, the wire cutting clutch assembly is in the engaged state and transmits power. Then, the feeding arm 331 contacts and cooperates with the wire cutting groove surface of the wire cutting drive arm 441 through the wire cutting ball 43 to push the wire cutting drive component 44, which in turn drives the wire cutting shaft 42 to rotate. Then, the moving blade 41 is driven to move through the wire cutting transmission assembly, and the wire cutting mechanism 40 performs automatic wire cutting.

[0099] Therefore, this application uses the same feeding and thread-cutting drive source 20 to drive the feeding mechanism and the thread-cutting mechanism, thereby realizing feeding and thread cutting; and by setting a thread-cutting clutch component in the thread-cutting mechanism 40, the thread-cutting mechanism 40 does not move during normal sewing feeding, ensuring that there is no interference between feeding and thread cutting; and when cutting the thread, the feeding and thread-cutting drive source 20 drives the moving blade 41 to move through the drive crank 33, the engaged thread-cutting clutch component and the thread-cutting transmission component in sequence, thereby realizing thread cutting. That is, the power for thread cutting comes from the feeding and thread-cutting drive source 20, and does not depend on other drive sources in the sewing machine, thereby simplifying the structure and shortening the transmission chain.

[0100] Furthermore, such as Figure 1As shown, the sewing machine also includes an integrated mounting base 10. The feed and thread-cutting drive source 20 is independent of the other drive sources in the sewing machine. The feed and thread-cutting drive source 20, the feed mechanism 30, and the thread-cutting mechanism 40 are all mounted on the integrated mounting base 10. Thus, the integrated mounting base 10, the feed and thread-cutting drive source 20, the feed mechanism 30, and the thread-cutting mechanism 40 are integrated into an independent functional module, defined as an independent feed and thread-cutting module. This independent feed and thread-cutting module integrates the feed function and the automatic thread-cutting function. The feed mechanism 30 and the thread-cutting mechanism 40 are modularized independently, making them independent of other functional mechanisms in the sewing machine. Using an independent feed and thread-cutting drive source 20 to drive the feed and thread-cutting independently, the power source for the feed and thread-cutting does not depend on other functional mechanisms in the sewing machine, thereby simplifying the structure of the feed mechanism 30 and the thread-cutting mechanism 40, effectively shortening their respective transmission chains, reducing space occupation, and minimizing interference with the installation and arrangement of other functional mechanisms in the sewing machine. Furthermore, by integrating and removing the mounting base 10 in the sewing machine, the independent feeding and thread cutting module can be installed and removed as a whole in the sewing machine. This allows the independent feeding and thread cutting module to be quickly adapted and installed in various sewing machine models, demonstrating strong compatibility. In other words, this application has developed a novel design platform for sewing machines.

[0101] Preferably, such as Figure 1 As shown, the feeding and thread-cutting drive source 20 is a drive motor 21, and the drive crank 33 is fixed to the motor shaft of the drive motor 21 by screws or other fasteners; the drive motor 21 is preferably a stepper motor. The integrated mounting base 10 has a horizontally arranged mounting main board 101 and a motor mounting plate 102 extending vertically from the right end of the mounting main board 101. The mounting main board 101 is fixed to the bottom of the sewing machine base plate 60 by screws or other fasteners, and the drive motor 21 is fixed to the right end of the motor mounting plate 102 by screws or other fasteners. The motor shaft of the drive motor 21 passes through the motor mounting plate 102.

[0102] The aforementioned independent feeding and wire cutting module, based on different structures of the wire cutting drive assembly and the feeding drive unit, results in multiple different embodiments of the independent feeding and wire cutting module. Two preferred embodiments of the independent feeding and wire cutting module are provided below.

[0103] Independent feeding and wire cutting module, Example 1

[0104] like Figures 3 to 6As shown, the feeding transmission unit includes a feeding link 34, a feeding shaft 35 that can rotate around its own axis and extends axially to the left and right, a feeding crank 36 fixed to the right end of the feeding shaft 35, and a toothed bracket seat 37 fixed to the left end of the feeding shaft 35; the integrated mounting base 10 also includes a feeding support part 103 integrally extended from the mounting main board 101, and the feeding shaft 35 is rotatably supported in the feeding support part 103 of the integrated mounting base 10 through bearings, bushings and other components; the two ends of the feeding link 34 are rotatably connected to the feeding arm 331 and the feeding crank 36 respectively, i.e., hinged, and the toothed bracket seat 37 is connected to the feeding connection part 311 of the toothed bracket 31; the effective length of the feeding arm 331 is less than the effective length of the feeding link 34. In addition, in the left-right direction, the feeding crank 36 is distributed on the right side of the feeding support 103, and the toothed bracket seat 37 is distributed on the left side of the feeding support 103. One end of the feeding connecting rod 34 and the outer end of the feeding arm 331, as well as the other end of the feeding connecting rod 34 and the feeding crank 36, are rotatably connected, i.e., hinged, by pins and bearings extending in the left and right axial directions. The bearings are assembled between the pins and the ends of the feeding connecting rod 34.

[0105] During normal sewing, the motor shaft of drive motor 21 oscillates back and forth within a certain angle range, driving the feed arm 331 of drive crank 33 to oscillate back and forth within a certain angle range in the feed working area X1. This, in turn, drives the feed shaft 35 to oscillate via feed connecting rod 34 and feed crank 36, which in turn drives the feed dog 31 and feed dog 32 to reciprocate back and forth via feed dog holder 37, thus feeding material. By adjusting the oscillation angle range of drive motor 21, the oscillation range of feed arm 331 within the feed working area X1 is adjusted, thereby adjusting the effective stitch length of the sewing machine, achieving feed stitch length adjustment, and thus adjusting the movement trajectory of feed dog 32. For example, the feed dog 32 can have the following characteristics: Figure 10a The elliptical motion trajectory shown, or making the feed tooth 32 have such a shape as indicated. Figure 10b The near-vertical motion trajectory shown, or making the feed tooth 32 have a shape like... Figure 10c The shown far-vertical motion trajectory, or making the feed tooth 32 have such a Figure 10d The rectangular motion trajectory is shown. Thus, the independent feeding and thread cutting module embodiment one has functions such as step adjustment of stitch length, backstitch switching, feeding trajectory switching, and pattern stitching.

[0106] Preferably, such as Figures 3 to 6As shown, the integrated mounting base 10 also includes a wire-cutting support portion 104 integrally extended from the mounting motherboard 101. The wire-cutting shaft 42 is rotatably supported in the wire-cutting support portion 104 of the integrated mounting base 10 via bearings, bushings, and other components. The wire-cutting arm 332 on the drive crank 33 is circumferentially offset from the feeding arm 331. Of course, in other embodiments, the wire-cutting arm 332 and the feeding arm 331 on the drive crank 33 can be circumferentially overlapped, and thus can be the same arm.

[0107] Furthermore, the wire cutting mechanism 40 can be a single-moving blade structure or a double-moving blade structure. In the first embodiment of the independent feeding wire cutting module, as shown... Figure 3 and Figure 4 As shown, the wire cutting mechanism 40 is a single-moving-blade structure. The wire cutting mechanism 40 also includes a fixed blade 45. The wire cutting transmission assembly includes a wire cutting crank 46 fixed on the wire cutting shaft 42, a wire cutting connecting rod 47, and a rotatable moving blade holder 48. The two ends of the wire cutting connecting rod 47 are respectively hinged to the wire cutting crank 46 and the moving blade holder 48. The moving blade 41 is fixed on the moving blade holder 48.

[0108] Preferably, such as Figure 3 and Figure 4 As shown, the wire cutting mechanism 40 also includes a return torsion spring 49 sleeved on the wire cutting shaft 42. The two ends of the return torsion spring 49 are connected to the integrated mounting base 10 and the wire cutting crank 46, respectively. After wire cutting is completed, the drive motor 21 rotates in the reverse direction, driving the feeding arm 331 from the end angle of the wire cutting working area X2. Reversing to the current angle within the feeding work area X1 before wire cutting, the wire cutting crank 46 is driven to reset under the action of the reset torsion spring 49, which in turn drives the wire cutting shaft 42, wire cutting connecting rod 47, moving blade holder 48, and other components to reset respectively; furthermore, when wire cutting is not required, the reset torsion spring 49 also keeps the wire cutting crank 46 in its initial position. More preferably, as Figure 8 and Figure 9 As shown, a reset arm 443 extends from the wire-cutting drive component 44. The reset arm 443 is circumferentially offset from the wire-cutting drive arm 441, and the outer circumferential surface of the reset arm 443 has a forced reset surface. The drive motor 21 drives the feeding arm 331 from the end angle of the wire-cutting working area X2. When the reverse rotation begins, the forced reset surface on the reset arm 443 contacts and engages with the wire cutting ball 43. The wire cutting ball 43 pushes the reset arm 443 to reset, thereby driving the wire cutting drive 44 to reset, which in turn drives all components in the wire cutting mechanism 40 to reset. This avoids the risk that the moving blade 41 will not be able to reset smoothly due to being stuck by the wire, ensuring that the moving blade 41 can get out of the fault position where it is stuck by the wire and ensuring that it can automatically cut the wire smoothly next time.

[0109] Furthermore, in Embodiment 1 of the independent feeding and wire cutting module, as follows: Figure 6As shown, the effective length of the feeding arm 331 is less than the effective length of the feeding connecting rod 34. The effective length of the feeding arm 331 refers to the distance between the center of the motor shaft of the drive motor 21 and the rotation center of the feeding arm 331 and the feeding connecting rod 34. The effective length of the feeding connecting rod 34 refers to the distance between the rotation center of the feeding arm 331 and the feeding connecting rod 34 and the rotation center of the feeding connecting rod 34 and the feeding crank 36. Therefore, the feeding mechanism 30 in the first embodiment of the independent feeding wire cutting module adopts a short crank-long connecting rod structure. The following configuration of the position angle of the feeding arm 331 and the feeding connecting rod 34 aims to minimize the forward and backward movement distance of the feeding tooth 32 during the wire cutting process, thereby achieving the wire cutting effect of short wire ends and improving the customer experience.

[0110] Specifically, such as Figure 11 As shown, circle O1 is drawn with the rotation center C of the feeding arm 331 as the center and the effective length CD of the feeding arm 331 as the radius. Point C is also the center of the motor shaft of the drive motor 21, and point D is the rotation center of the feeding arm 331 and the feeding connecting rod 34. Circle O2 is drawn with the hinge point B of the feeding connecting rod 34 and the feeding crank 36 as the center and the effective length BD of the feeding connecting rod 34 as the radius. Point A is the center of the feeding shaft 35. Circles O1 and O2 are basically coincident within an angle range of ±β on both sides of the collinear position of the feeding arm 331 and the feeding connecting rod 34. Let the angle of the feeding arm 331 when the feeding arm 331 and the feeding connecting rod 34 are collinear be denoted as . Then the feeding arm 331 is in During movement within this range, the feed crank 36 remains essentially stationary, meaning the displacement of the feed tooth 32 in the forward and backward directions is very small, and there is essentially no feeding. That is, when the angle of the feed arm 331 is within... Within this range, the independent feed and thread-cutting module enables the sewing machine to have a small stitch pitch; in this embodiment, when the angle of the feed arm 331 is within... Within this range, the independent feeding and wire-cutting module ensures that the movement of the feeding tooth 32 in the front-to-back direction does not exceed 1 mm. Based on this, the wire-cutting working area X2 of the feeding arm 331 is set at... Within this range, the movement distance of the feed tooth 32 in the front-to-back direction during the wire cutting process is very small; therefore, the wire cutting working area X2 of the feed arm 331 can be set as follows: Thus, the wire-cutting working area X2 of the feeding arm 331 can have the following three embodiments.

[0111] Example 1: Wire cutting work area X2 of feeding arm 331 Figure 12a As shown,

[0112] Example 2: Wire cutting work area X2 of feeding arm 331 Figure 12b As shown,

[0113] Example 3: Wire cutting work area X2 of feeding arm 331 Figure 12c As shown,

[0114] Furthermore, when the feeding arm 331 and the feeding link 34 are collinear, the feeding tooth 32 is located at the front limit position within its reciprocating range, thus the feeding tooth 32 has a minimum limit distance with the front end of the tooth groove of the needle plate. Alternatively, when the feeding arm 331 and the feeding link 34 are collinear, the feeding tooth 32 is located at the rear limit position within its reciprocating range, thus the feeding tooth 32 has a minimum limit distance with the rear end of the tooth groove of the needle plate.

[0115] Independent feeding and wire cutting module, Example 2

[0116] like Figures 13 to 15 As shown, the feeding transmission unit includes a feeding link 34, a feeding shaft 35 that can rotate around its own axis and extends axially to the left and right, a tooth holder seat 37 fixed on the feeding shaft 35, and a feeding connecting arm 371 fixedly connected to the tooth holder seat 37. The feeding shaft 35 is rotatably supported in the integrated mounting base 10. The two ends of the feeding link 34 are rotatably connected to the feeding arm 331 and the feeding connecting arm 371 respectively, i.e., hinged. The tooth holder seat 37 is connected to the feeding connection part 311 of the tooth holder 31. The effective length of the feeding arm 331 is greater than the effective length of the feeding link 34. The feeding connecting arm 371 and the tooth holder seat 37 can be an integral structure, in which case the feeding connecting arm 371 is integrally provided on the outer circumference of the tooth holder seat 37; or, the feeding connecting arm 371 and the tooth holder seat 37 are separate parts, and the two are fixedly connected by screws.

[0117] In the second embodiment of the independent feeding and wire cutting module, the wire cutting arm 332 and the feeding arm 331 on the drive crank 33 are the same arm. The outer end of this common arm, the feeding connecting rod 34, and the wire cutting ball 43 are coaxially connected by a left-right extending pin. The feeding connecting rod 34 is distributed on the left side of the common arm, and the wire cutting ball 43 is distributed on the right side of the common arm. The wire cutting mechanism 40 is a single-moving blade structure. The wire cutting mechanism 40 also includes a fixed blade 45. A wire cutting connecting arm 442 extends from the wire cutting drive member 44. The wire cutting drive arm 441 and the wire cutting connecting arm 442 are circumferentially staggered. The wire cutting transmission assembly includes a wire cutting connecting rod 47 and a rotatable moving blade holder 48. The two ends of the wire cutting connecting rod 47 are hinged to the wire cutting connecting arm 442 and the moving blade holder 48, respectively. The moving blade 41 is fixed on the moving blade holder 48. Of course, in other embodiments, the wire cutting mechanism 40 can also adopt a double-moving blade structure.

[0118] During normal sewing, the motor shaft of drive motor 21 oscillates back and forth within a certain angle range, driving the feed arm 331 of drive crank 33 to oscillate back and forth within a certain angle range in the feed working area X1. In other words, the feed arm 331 operates within the feed working area X1. At this time, the feed shaft 35 is driven to oscillate via feed connecting rod 34, which in turn drives the feed dog 31 and feed dog 32 to reciprocate back and forth via feed dog seat 37, allowing the feed dog 32 to feed normally. Meanwhile, the thread cutting ball 43 separates from the thread cutting groove surface on the thread cutting drive arm 441, thus disengaging the thread cutting clutch assembly and preventing power transmission. Consequently, the thread cutting mechanism 40 does not perform the thread cutting action. Furthermore, when the feed arm 331 of drive crank 33 operates within the feed working area X1, the independent feed and thread cutting module ensures that the sewing machine has an effective stitch length. The effective stitch length includes a positive stitch length corresponding to the forward sewing state and a negative stitch length corresponding to the reverse sewing state. Furthermore, by adjusting the swing angle range of the drive motor 21, the swing range of the feed arm 331 of the drive crank 33 within the feed working area X1 is also adjusted, thereby adjusting the effective stitch length of the sewing machine, achieving adjustment of the feed stitch length, and thus adjusting the movement trajectory of the feed dog 32. For example, the feed dog 32 can be made to have such... Figure 19a The elliptical motion trajectory shown, or making the feed tooth 32 have such a shape as indicated. Figure 19b The near-vertical motion trajectory shown, or making the feed tooth 32 have a shape like... Figure 19c The shown far-vertical motion trajectory, or making the feed tooth 32 have such a Figure 19d The rectangular motion trajectory is shown. Thus, the independent feeding and thread cutting module embodiment one has functions such as step adjustment of stitch length, backstitch switching, feeding trajectory switching, and pattern stitching.

[0119] When wire trimming is required, drive motor 21 drives the feeding arm 331 to rotate clockwise from the current angle in the feeding working area X1 to the starting angle in the wire trimming working area X2. Then, continue rotating forward to the endpoint angle of the wire cutting work area X2. From the feed arm 331 Turning to During this process, the feeding arm 331 operates within the wire cutting working area X2, and the wire cutting ball 43 gradually approaches the wire cutting groove surface of the wire cutting drive arm 441 until it makes contact, as... Figure 18 As shown, the wire cutting clutch assembly is in the engaged state and transmits power. Then, the feeding arm 331 contacts and cooperates with the wire cutting groove surface of the wire cutting drive arm 441 through the wire cutting ball 43 to push the wire cutting drive component 44. Then, the moving blade 41 is driven to move through the wire cutting connecting rod 47 and the moving blade holder 48, and the wire cutting mechanism 40 performs automatic wire cutting.

[0120] Furthermore, the wire cutting mechanism 40 also includes a return torsion spring 49 sleeved on the wire cutting shaft 42, with its two ends connected to the integrated mounting base 10 and the wire cutting connecting arm 442, respectively. After wire cutting is completed, the drive motor 21 rotates in the reverse direction, driving the feeding arm 331 from the end angle of the wire cutting working area X2. Reversing to the current angle within the feeding work area X1 before wire cutting, the wire cutting drive 44 is driven to rotate in the opposite direction and reset under the action of the reset torsion spring 49. This also drives the wire cutting shaft 42, wire cutting connecting rod 47, moving blade holder 48, and other components to reset. Furthermore, when wire cutting is not required, the reset torsion spring 49 also keeps the wire cutting drive 44 in its initial position. More preferably, as... Figure 18 As shown, a reset arm 443 extends from the wire-cutting drive component 44. The reset arm 443 is circumferentially offset from the wire-cutting drive arm 441, and the outer circumferential surface of the reset arm 443 has a forced reset surface. The drive motor 21 drives the feeding arm 331 from the end angle of the wire-cutting working area X2. When the reverse rotation begins, the forced reset surface on the reset arm 443 contacts and engages with the wire cutting ball 43. The wire cutting ball 43 pushes the reset arm 443 to reset, thereby driving the wire cutting drive 44 to reset, which in turn drives all components in the wire cutting mechanism 40 to reset. This avoids the risk that the moving blade 41 will not be able to reset smoothly due to being stuck by the wire, ensuring that the moving blade 41 can get out of the fault position where it is stuck by the wire and ensuring that it can automatically cut the wire smoothly next time.

[0121] Furthermore, in Embodiment 2 of the independent feeding and wire cutting module, as follows: Figure 15 As shown, the effective length of the feeding arm 331 is greater than the effective length of the feeding link 34. The effective length of the feeding arm 331 refers to the distance between the center of the motor shaft of the drive motor 21 and the rotation center of the feeding arm 331 and the feeding link 34. The effective length of the feeding link 34 refers to the distance between the rotation center of the feeding arm 331 and the feeding link 34 and the rotation center of the feeding link 34 and the feeding connecting arm 371. Therefore, the feeding mechanism 30 in Embodiment 2 of the independent feeding and wire cutting module adopts a long crank-short connecting rod structure. The following configuration of the position angle of the feeding arm 331 and the feeding link 34 aims to minimize the forward and backward movement distance of the feeding tooth 32 during the wire cutting process, thereby achieving the wire cutting effect of short wire ends and improving the customer experience.

[0122] Specifically, such as Figure 20As shown, circle O3 is drawn with the rotation center E of the feeding arm 331 as the center and the effective length EF of the feeding arm 331 as the radius. Point E is also the center of the motor shaft of the drive motor 21, and point F is the rotation center of the feeding arm 331 and the feeding connecting rod 34. Circle O4 is drawn with the hinge point G of the feeding connecting rod 34 and the feeding connecting arm 371 as the center and the effective length FG of the feeding connecting rod 34 as the radius. Circles O3 and O4 are basically coincident within a ±β angle range on both sides of the collinear position of the feeding arm 331 and the feeding connecting rod 34. Let the angle of the feeding arm 331 when the feeding arm 331 and the feeding connecting rod 34 are collinear be denoted as . Then the feeding arm 331 is in During movement within this range, the four-bar linkage consisting of the drive crank 33, feed connecting rod 34, tooth holder seat 37, and tooth holder 31 forms an intermittent mechanism, creating a pause period. Specifically, the positional change of the hinge point of the feed connecting arm 371 of the feed connecting rod 34 and tooth holder seat 37 is small, and the positional angle change of the tooth holder seat 37 is small. The tooth holder seat 37 remains essentially stationary, resulting in very small displacement of the feed tooth 32 in the forward and backward direction, essentially no feeding. That is, when the angle of the feed arm 331 is within... Within this range, the independent feed and thread-cutting module enables the sewing machine to have a small stitch pitch; in this embodiment, when the angle of the feed arm 331 is within... Within this range, the independent feeding and wire-cutting module ensures that the movement of the feeding tooth 32 in the front-to-back direction does not exceed 1 mm. Based on this, the wire-cutting working area X2 of the feeding arm 331 is set at... Within this range, the movement distance of the feed tooth 32 in the front-to-back direction during the wire cutting process is very small; therefore, the wire cutting working area X2 of the feed arm 331 can be set as follows: Thus, the wire-cutting working area X2 of the feeding arm 331 can have the following three embodiments.

[0123] Example 1: Wire cutting work area X2 of feeding arm 331 Figure 21a As shown,

[0124] Example 2: Wire cutting work area X2 of feeding arm 331 Figure 21b As shown,

[0125] Example 3: Wire cutting work area X2 of feeding arm 331 Figure 21c As shown,

[0126] Furthermore, when the feeding arm 331 and the feeding link 34 are collinear, the feeding tooth 32 is located at the front limit position within its reciprocating range, thus the feeding tooth 32 has a minimum limit distance with the front end of the tooth groove of the needle plate. Alternatively, when the feeding arm 331 and the feeding link 34 are collinear, the feeding tooth 32 is located at the rear limit position within its reciprocating range, thus the feeding tooth 32 has a minimum limit distance with the rear end of the tooth groove of the needle plate.

[0127] Furthermore, in addition to the aforementioned independent feeding and thread-cutting module, the sewing machine also includes, for example... Figures 1 to 3 As shown, the sewing machine also includes a tooth-lifting drive source, a tooth-lifting mechanism 50, and a fixed base plate 60. The tooth-lifting mechanism 50 is connected between the tooth-lifting drive source and the tooth-lifting connection part 312 at the rear end of the tooth holder 31. By installing and removing the integrated mounting base 10 in the sewing machine, the independent feeding and thread-cutting module can be installed and removed as a whole. This allows the independent feeding and thread-cutting module to be quickly adapted and installed as a separate functional mechanism in various sewing machine models without interfering with other functional mechanisms of the sewing machine, demonstrating strong compatibility. Preferably, the integrated mounting base 10 and the base plate 60 are detachably connected by several screws, facilitating easy installation and removal. Figure 1 As shown, the independent feeding and thread cutting modules are located on the left side of the base plate 60 near the sewing machine head.

[0128] Furthermore, such as Figure 2 or Figure 3 As shown, the tooth-lifting drive source is the main motor of the sewing machine. The tooth-lifting mechanism 50 includes a main shaft 51 driven to rotate by the main motor, a tooth-lifting shaft 52 parallel to the main shaft 51, a first tooth-lifting transmission assembly connected between the main shaft 51 and the tooth-lifting shaft 52, and a second tooth-lifting transmission assembly connected between the tooth-lifting shaft 52 and the tooth-lifting connecting part 312 of the tooth frame 31. Both the main shaft 51 and the tooth-lifting shaft 52 extend axially in the left-right direction.

[0129] When the independent feeding and cutting module is compatible with the oscillating tooth lifting machine, such as Figure 2As shown, the first tooth-lifting transmission assembly includes a tooth-lifting eccentric wheel 53 fixed on the main shaft 51, a tooth-lifting crank 54 fixed on the right end of the tooth-lifting shaft 52, and a tooth-lifting connecting rod 55. The upper end of the tooth-lifting connecting rod 55 is rotatably sleeved on the outer circumference of the tooth-lifting eccentric wheel 53, and the lower end of the tooth-lifting connecting rod 55 is hinged to the tooth-lifting crank 54. The second tooth-lifting transmission assembly includes a tooth-lifting fork-shaped crank 56 fixed on the left end of the tooth-lifting shaft 52, and a tooth-lifting slider 57 hinged to the tooth-lifting connection part 312 of the tooth frame 31. The tooth-lifting fork-shaped crank 56 has a tooth-lifting groove that slides with the tooth-lifting slider 57. The main motor drives the main shaft 51 to rotate, and the main shaft 51 drives the tooth-lifting shaft 52 to swing through the first tooth-lifting transmission assembly. The tooth-lifting shaft 52 drives the tooth-lifting fork-shaped crank 56 to swing up and down through the second tooth-lifting transmission assembly, thereby realizing the up and down reciprocating motion of the tooth frame 31 and the feeding tooth 32, and performing the tooth-lifting action. The up-and-down lifting motion of the feed tooth 32 and the forward-and-backward feeding motion together constitute the feeding trajectory of the feed tooth 32. Of course, in other embodiments, the second lifting transmission assembly can adopt a transmission pair with other structures.

[0130] When the independent feeding and cutting module is compatible with the rotary tooth lifting machine, such as Figure 3 As shown, the first tooth-lifting transmission assembly includes a driving pulley 58 fixed on the main shaft 51, a driven pulley 59 fixed on the right end of the tooth-lifting shaft 52, and a transmission belt 510 connecting the outer periphery of the driving pulley 58 and the driven pulley 59. The speed ratio of the driving pulley 58 to the driven pulley 59 is 1:1. The second tooth-lifting transmission assembly includes a tooth-lifting eccentric wheel 53 fixed on the left end of the tooth-lifting shaft 52 and a tooth-lifting connecting rod 55. One end of the tooth-lifting connecting rod 55 is rotatably sleeved on the outer periphery of the tooth-lifting eccentric wheel 53, and the other end of the tooth-lifting connecting rod 55 is hinged to the tooth-lifting connection part 312 of the tooth holder 31. The main motor drives the main shaft 51 to rotate, and the main shaft 51 drives the tooth-lifting shaft 52 to rotate through the first tooth-lifting transmission assembly. The tooth-lifting shaft 52 drives the tooth holder 31 and the feeding tooth 32 to reciprocate up and down through the second tooth-lifting transmission assembly, thus performing the tooth-lifting action. The up-and-down lifting motion of the feed tooth 32 and the forward-and-backward feeding motion together constitute the feeding trajectory of the feed tooth 32. Of course, in other embodiments, the second lifting transmission assembly can adopt a transmission pair with other structures.

[0131] In summary, the independent feeding and thread-cutting module and sewing machine of the present invention have the following advantages:

[0132] 1. The independent feeding and thread cutting module can be used as an independent unit module to adapt to various types of sewing machine models, with strong compatibility, and has developed a new design platform for sewing machines.

[0133] 2. The independent feeding and thread cutting module integrates the feeding mechanism 30 and the thread cutting mechanism 40 into one, which has a simplified structure, short transmission chain, small installation space, and does not interfere with other functional mechanisms of the sewing machine.

[0134] 3. The same drive motor 21 is used for both feeding and wire cutting, and the two do not interfere with each other.

[0135] 4. By adjusting the output angle of the drive motor 21, functions such as stitch length adjustment, backstitch switching, feed dog 32 trajectory switching, and pattern stitching can be realized. It has comprehensive functions and wide adaptability.

[0136] 5. The thread cutting mechanism 40 can be driven by the drive motor 21 to achieve thread cutting without relying on other drive sources in the sewing machine, thus ensuring the independent modularity of the independent feeding and thread cutting module.

[0137] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0138] 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 sewing machine that uses the same drive source for feeding and thread trimming, characterized in that: It includes a feeding and wire cutting drive source (20), a feeding mechanism (30), and a wire cutting mechanism (40). The feeding mechanism (30) includes a toothed frame (31), a feeding tooth (32) fixed on the toothed frame (31), a drive crank (33) driven to rotate by a feeding wire cutting drive source (20), and a feeding transmission unit. A feeding arm (331) extends from the drive crank (33), and the feeding transmission unit is connected between the feeding arm (331) and the feeding connection part (311) of the toothed frame (31). The wire cutting mechanism (40) includes a movable blade (41), a wire cutting arm (332) driven to rotate by a feeding wire cutting drive source (20), a wire cutting shaft (42) rotatable about its own axis, a wire cutting clutch assembly, and a wire cutting transmission assembly connected between the wire cutting shaft (42) and the movable blade (41). The wire cutting clutch assembly includes a wire cutting ball (43) and a wire cutting drive member (44) fixed on the wire cutting shaft (42). A wire cutting drive arm (441) extends from the wire cutting drive member (44). The wire cutting ball (43) is rotatably mounted on the wire cutting arm (332), and the wire cutting drive arm (441) is provided with a wire cutting groove surface. Alternatively, the wire cutting ball (43) is rotatably mounted on the wire cutting drive arm (441), and the wire cutting arm (332) is provided with a wire cutting groove surface. During the process of the feed and thread-cutting drive source (20) driving the drive crank (33) to rotate, the angle of the feed arm (331) has an independent feed working area and a thread-cutting working area: when the feed arm (331) operates in the feed working area, the sewing machine has an effective stitch pitch, and the thread-cutting ball (43) is separated from the thread-cutting groove surface; when the feed arm (331) operates in the thread-cutting working area, the thread-cutting ball (43) is in contact with the thread-cutting groove surface. When the angle of the feed arm (331) is within the range of φ0±β, the sewing machine has a small stitch pitch, and the thread cutting working area of ​​the feed arm (331) is set within the range of φ0±β.

2. The sewing machine according to claim 1, characterized in that: The wire cutting mechanism (40) is a single-moving blade structure. The wire cutting mechanism (40) also includes a fixed blade (45) that is fixedly set. The wire cutting transmission assembly includes a wire cutting crank (46) fixed on the wire cutting shaft (42), a wire cutting connecting rod (47), and a rotatable moving blade holder (48). The two ends of the wire cutting connecting rod (47) are respectively hinged to the wire cutting crank (46) and the moving blade holder (48). The moving blade (41) is fixed on the moving blade holder (48).

3. The sewing machine according to claim 2, characterized in that: The wire cutting mechanism (40) also includes a reset torsion spring (49) sleeved on the wire cutting shaft (42), one end of which is fixed and the other end is connected to the wire cutting crank (46).

4. The sewing machine according to claim 1, characterized in that: The wire cutting mechanism (40) is a single-moving blade structure. The wire cutting mechanism (40) also includes a fixed blade (45). The wire cutting transmission assembly includes a wire cutting connecting arm (442), a wire cutting connecting rod (47), and a rotatable moving blade holder (48) extending from the wire cutting drive member (44). The two ends of the wire cutting connecting rod (47) are respectively hinged to the wire cutting connecting arm (442) and the moving blade holder (48). The moving blade (41) is fixed on the moving blade holder (48).

5. The sewing machine according to claim 4, characterized in that: The wire cutting mechanism (40) also includes a reset torsion spring (49) sleeved on the wire cutting shaft (42), one end of which is fixed and the other end is connected to the wire cutting connecting arm (442).

6. The sewing machine according to claim 1, characterized in that: When the wire-cutting ball (43) is rotatably mounted on the wire-cutting arm (332), a reset arm (443) extends from the wire-cutting drive (44). The reset arm (443) is circumferentially offset from the wire-cutting drive arm (441), and the forced reset surface on the reset arm (443) can contact and cooperate with the wire-cutting ball (43).

7. The sewing machine according to claim 1, characterized in that: The feeding transmission unit includes a feeding connecting rod (34), a feeding shaft (35) that can rotate around its own axis, a feeding crank (36) fixed to one end of the feeding shaft (35), and a toothed bracket seat (37) fixed to the other end of the feeding shaft (35). The two ends of the feeding connecting rod (34) are rotatably connected to the feeding arm (331) and the feeding crank (36) respectively. The toothed bracket seat (37) is connected to the feeding connection part (311) of the toothed bracket (31). The effective length of the feeding arm (331) is less than the effective length of the feeding connecting rod (34). When the feeding arm (331) and the feeding connecting rod (34) are collinear, the angle of the feeding arm (331) is φ0.

8. The sewing machine according to claim 1, characterized in that: The feeding transmission unit includes a feeding link (34), a feeding shaft (35) that can rotate around its own axis, a tooth holder seat (37) fixed on the feeding shaft (35), and a feeding connecting arm (371) fixedly connected to the tooth holder seat (37). The two ends of the feeding link (34) are rotatably connected to the feeding arm (331) and the feeding connecting arm (371) respectively. The tooth holder seat (37) is connected to the feeding connecting part (311) of the tooth holder (31). The effective length of the feeding arm (331) is greater than the effective length of the feeding link (34).

9. The sewing machine according to claim 1, characterized in that: It also includes a tooth-lifting drive source and a tooth-lifting mechanism (50). The tooth-lifting drive source is the main motor of the sewing machine. The tooth-lifting mechanism (50) includes a main shaft (51) driven to rotate by the main motor, a tooth-lifting shaft (52) parallel to the main shaft (51), a first tooth-lifting transmission assembly connected between the main shaft (51) and the tooth-lifting shaft (52), and a second tooth-lifting transmission assembly connected between the tooth-lifting shaft (52) and the tooth-lifting connecting part (312) of the tooth holder (31). The first tooth-lifting transmission assembly includes a tooth-lifting eccentric wheel (53) fixed on the main shaft (51) and a tooth-lifting shaft (54). (52) A tooth lifting crank (54) at one end and a tooth lifting connecting rod (55), one end of which is rotatably sleeved on the outer periphery of the tooth lifting eccentric wheel (53), and the other end of which is hinged to the tooth lifting crank (54); the second tooth lifting transmission assembly includes a tooth lifting fork-shaped crank (56) fixed at the other end of the tooth lifting shaft (52) and a tooth lifting slider (57) hinged to the tooth lifting connection part (312) of the tooth frame (31), wherein the tooth lifting fork-shaped crank (56) has a tooth lifting groove that slides with the tooth lifting slider (57).

10. The sewing machine according to claim 1, characterized in that: It also includes a tooth-lifting drive source and a tooth-lifting mechanism (50). The tooth-lifting drive source is the main motor of the sewing machine. The tooth-lifting mechanism (50) includes a main shaft (51) driven to rotate by the main motor, a tooth-lifting shaft (52) parallel to the main shaft (51), a first tooth-lifting transmission assembly connected between the main shaft (51) and the tooth-lifting shaft (52), and a second tooth-lifting transmission assembly connected between the tooth-lifting shaft (52) and the tooth-lifting connecting part (312) of the tooth holder (31). The first tooth-lifting transmission assembly includes an active belt fixed on the main shaft (51). The second tooth lifting transmission assembly includes a tooth lifting eccentric wheel (53) fixed at one end of the tooth lifting shaft (52), a driven pulley (59) fixed at one end of the tooth lifting shaft (52), and a transmission belt (510) connected to the outer periphery of the driving pulley (58) and the driven pulley (59); the second tooth lifting transmission assembly includes a tooth lifting eccentric wheel (53) fixed at the other end of the tooth lifting shaft (52) and a tooth lifting connecting rod (55), one end of the tooth lifting connecting rod (55) being rotatably sleeved on the outer periphery of the tooth lifting eccentric wheel (53), and the other end of the tooth lifting connecting rod (55) being hinged to the tooth lifting connection part (312) of the tooth frame (31).

Images