CN117904808A - Sewing machine for feeding and trimming threads by adopting same driving source - Google Patents

Abstract

The application provides a sewing machine for feeding and cutting threads by adopting the same driving source, which comprises a feeding thread cutting driving source, a feeding mechanism and a thread cutting mechanism; the feeding mechanism comprises a tooth frame, feeding teeth, a driving crank and a feeding transmission unit, wherein the driving crank is driven by a feeding wire cutting driving source to rotate; the wire cutting mechanism comprises a movable cutter, a wire cutting arm extending from a driving crank, a wire cutting shaft, a wire cutting clutch assembly and a wire cutting transmission assembly in transmission connection between the wire cutting shaft and the movable cutter, wherein the wire cutting clutch assembly comprises a wire cutting ball rotatably installed on the wire cutting arm and a wire cutting driving piece fixed on the wire cutting shaft. The application adopts the same feeding and thread cutting driving source to drive the feeding mechanism and the thread cutting mechanism, and when the thread is cut, the feeding and thread cutting driving source drives the movable cutter to move through the driving crank, the engaged thread cutting clutch component and the thread cutting transmission component in sequence, thereby realizing thread cutting, and the thread cutting power is independent of other driving sources in the sewing machine, so that the structure is simplified, and the transmission chain is shortened.

Description

Sewing machine for feeding and trimming threads by adopting same driving source

Technical Field

The invention relates to the technical field of sewing machines, in particular to a sewing machine for feeding and trimming threads by adopting the same driving source.

Background

At present, each large sewing machine company has own design platform, and a feeding mechanism, a feed lifting mechanism, a thread trimming mechanism and a presser foot lifting mechanism are important functional mechanisms of the sewing machine, once the design platform of a certain company is determined, the research and development of products and next generation products are iterative update based on the design platform, and the research and development of another brand new design platform can be hardly performed.

Such as: the driving mechanism of the lockstitch sewing machine disclosed in China patent application number 201220297729.6 drives a feed lifting shaft and a feed feeding shaft to rotate through a main shaft (namely an upper shaft), the main shaft is driven to rotate by a main motor, the feed lifting shaft drives a feed lifting assembly to reciprocate up and down through a set of feed lifting assembly to drive a feed lifting assembly and feed feeding teeth to reciprocate back and forth to execute feed lifting action, and meanwhile, the main shaft drives a lower shaft to rotate through a set of synchronous belt pulley mechanism to drive a rotating shuttle mechanism to rotate to execute thread hooking action. Further, the sewing machine may be further provided with a thread cutting mechanism, such as an automatic thread cutting mechanism disclosed in chinese patent application No. 201710215982.X, wherein when thread cutting is required, the thread cutting driving source acts, so that the thread cutting ball contacts with the thread cutting cam fixed on the lower shaft, and then the thread cutting assembly is driven to operate by rotation of the lower shaft to perform automatic thread cutting. Obviously, the structure of the feeding mechanism, the lifting tooth mechanism and the thread cutting mechanism in the sewing machine with the structure is complex, the number of parts is large, the transmission chain is long, and the thread cutting mechanism is provided with the clutch assembly to realize thread cutting action.

And, for example: the invention patent of China with the application number 201210365288.3 discloses a sewing machine, a feed lifting mechanism is driven by a main shaft in the sewing machine, the main shaft is driven by a main motor to rotate, a feeding mechanism is driven by a feeding motor, and the clutch of a thread cutting mechanism is driven by the feeding motor; when cutting the wire, after the transmission part in the feeding motor driving wire cutting mechanism is combined, the wire cutting cam on the lower shaft still drives the wire cutting assembly to operate so as to execute automatic wire cutting action. Obviously, the structure of the sewing machine is complex, particularly, a grooved cam structure is used, the grooved cam structure is difficult to implement, and the grooved cam structure still needs to rely on a main motor to drive a main shaft to rotate, the main shaft to drive a lower shaft to rotate and the lower shaft to drive a thread cutting cam to rotate when a thread is cut, so that the thread cutting action is completed.

For another example: a thread cutting and presser foot lifting device of a sewing machine is disclosed in China patent application number 201520782770.6, and a stepping motor performs thread cutting driving and presser foot lifting driving through a set of complex mechanisms. However, as the final execution end (namely the movable knife and the fixed knife) in the thread cutting mechanism is arranged at the left end of the bottom plate, and the final execution end (namely the presser foot) in the presser foot lifting mechanism is arranged at the machine head, the span between the stepping motor and the movable knife and between the stepping motor and the presser foot is large, so that the whole transmission chain of the sewing machine is longer, the stepping motor and the transmission structure occupy most of the installation space in the bottom plate, and certain interference is caused to the arrangement and the installation of other transmission structures in the sewing machine.

And, for example: the utility model patent of China with the application number 202120273965.3 discloses a sewing machine with a positioning feed dog stop position, which drives a swinging seat to rotate through a stepping motor, so that the swinging seat is positioned at different position angles, and the different position angles of the swinging seat correspond to different needle pitches; meanwhile, the stepping motor drives a thread cutting assembly such as a thread cutting fork wheel to operate through a thread cutting crank wheel, and executes thread cutting action. However, the sewing machine has the advantages of a large number of parts, long transmission chain, poor structural stability, quite complex transmission such as needle pitch adjustment and thread cutting driving, and the like, and simultaneously, the structure also uses a groove-shaped cam structure with great implementation difficulty.

In summary, the existing sewing machine has the following problems: 1. the structure is complex, so that the stability is poor, and the implementation difficulty is high; 2. the transmission chain is long, so that a transmission structure comprising a stepping motor occupies most of the installation space of the machine, and the arrangement and the installation of other structures are interfered; 3. the function is single, the power of the thread cutting mechanism still depends on the main shaft or depends on the main motor, and the power source arranged in the thread cutting mechanism can only realize the switching of thread cutting clutch.

Disclosure of Invention

In view of the above-described drawbacks of the prior art, an object of the present invention is to provide a sewing machine that uses the same driving source for feeding and cutting threads, wherein the driving source for feeding and cutting threads can independently drive feeding and cutting threads, so that the power source for cutting threads is independent of other driving sources in the sewing machine.

In order to achieve the above purpose, the invention provides a sewing machine for feeding and cutting threads by adopting the same driving source, which comprises a feeding thread cutting driving source, a feeding mechanism and a thread cutting mechanism;

the feeding mechanism comprises a tooth frame, feeding teeth fixed on the tooth frame, a driving crank driven to rotate by a feeding wire cutting driving source and a feeding transmission unit, wherein a feeding arm extends out of the driving crank, and the feeding transmission unit is in transmission connection between the feeding arm and a feeding connecting part of the tooth frame;

The wire cutting mechanism comprises a movable knife, a wire cutting arm driven to rotate by a feeding wire cutting driving source, a wire cutting shaft capable of rotating around the axis of the wire cutting arm, a wire cutting clutch assembly and a wire cutting transmission assembly in transmission connection between the wire cutting shaft and the movable knife, wherein the wire cutting clutch assembly comprises a wire cutting ball and a wire cutting driving piece fixed on the wire cutting shaft, and a wire cutting driving arm extends out of the wire cutting driving piece; the thread cutting ball is rotatably arranged on the thread cutting arm, and the thread cutting driving arm is provided with a thread cutting sliding groove surface, or the thread cutting ball is rotatably arranged on the thread cutting driving arm, and the thread cutting arm is provided with a thread cutting sliding groove surface;

In the process that the feeding wire cutting driving source drives the driving crank to rotate, the angle of the feeding arm is provided with a feeding working area and a wire cutting working area which are mutually independent: when the feeding arm runs in the feeding working area, the sewing machine has an effective needle distance, and the thread cutting ball is separated from the thread cutting sliding groove surface; when the feeding arm runs in the thread cutting working area, the thread cutting balls are in contact fit with the thread cutting sliding groove surface.

Further, the thread cutting mechanism is of a single-acting cutter structure, the thread cutting mechanism further comprises a fixed cutter which is fixedly arranged, the thread cutting transmission assembly comprises a thread cutting crank, a thread cutting connecting rod and a rotatable moving cutter frame which are fixed on the thread cutting shaft, two ends of the thread cutting connecting rod are respectively hinged with the thread cutting crank and the moving cutter frame, and the moving cutter is fixed on the moving cutter frame.

Further, the thread cutting mechanism further comprises a reset torsion spring sleeved on the thread cutting shaft, one end of the reset torsion spring is fixed, and the other end of the reset torsion spring is connected with the thread cutting crank.

Further, the thread cutting mechanism is of a single-acting cutter structure, the thread cutting mechanism further comprises a fixed cutter which is fixedly arranged, the thread cutting transmission assembly comprises a thread cutting connecting arm, a thread cutting connecting rod and a rotatable moving cutter frame which extend from the thread cutting driving piece, two ends of the thread cutting connecting rod are hinged with the thread cutting connecting arm and the moving cutter frame respectively, and the moving cutter is fixed on the moving cutter frame.

Further, the thread cutting mechanism further comprises a reset torsion spring sleeved on the thread cutting shaft, one end of the reset torsion spring is fixed, and the other end of the reset torsion spring is connected with the thread cutting connecting arm.

Further, a reset arm is further extended from the wire cutting driving piece, the reset arm and the wire cutting driving arm are distributed in a staggered mode in the circumferential direction, and a forced reset surface on the reset arm can be in contact fit with the wire cutting ball.

Further, the feeding transmission unit comprises a feeding connecting rod, a feeding shaft capable of rotating around the axis of the feeding connecting rod, a feeding crank fixed at one end of the feeding shaft and a dental frame seat fixed at the other end of the feeding shaft, wherein two ends of the feeding connecting rod are respectively connected with the feeding arm and the feeding crank in a rotating way, and the dental frame seat is connected with a feeding connecting part of a dental frame; the effective length of the feeding arm is smaller than that of the feeding connecting rod.

Further, the feeding transmission unit comprises a feeding connecting rod, a feeding shaft capable of rotating around the axis of the feeding connecting rod, a dental frame seat fixed on the feeding shaft and a feeding connecting arm fixedly connected with the dental frame seat, wherein two ends of the feeding connecting rod are respectively connected with the feeding arm and the feeding connecting arm in a rotating way, and the dental frame seat is connected with a feeding connecting part of the dental frame; the effective length of the feeding arm is greater than that of the feeding connecting rod.

Further, the sewing machine also comprises a lifting tooth driving source and a lifting tooth mechanism, wherein the lifting tooth driving source is a main motor of the sewing machine, and the lifting tooth mechanism comprises a main shaft driven by the main motor to rotate, a lifting tooth shaft parallel to the main shaft, a first lifting tooth transmission assembly connected between the main shaft and the lifting tooth shaft, and a second lifting tooth transmission assembly connected between the lifting tooth shaft and a lifting tooth connecting part of the tooth frame; the first lifting tooth transmission assembly comprises a lifting tooth eccentric wheel fixed on the main shaft, a lifting tooth crank fixed at one end of a lifting tooth shaft and a lifting tooth connecting rod, one end of the lifting tooth connecting rod is rotatably sleeved on the periphery of the lifting tooth eccentric wheel, and the other end of the lifting tooth connecting rod is hinged with the lifting tooth crank; the second lifting tooth transmission assembly comprises a lifting tooth fork-shaped crank fixed at the other end of the lifting tooth shaft and a lifting tooth sliding block hinged with the lifting tooth connecting part of the tooth frame, and a lifting tooth sliding groove in sliding fit with the lifting tooth sliding block is formed in the lifting tooth fork-shaped crank.

Further, the sewing machine also comprises a lifting tooth driving source and a lifting tooth mechanism, wherein the lifting tooth driving source is a main motor of the sewing machine, and the lifting tooth mechanism comprises a main shaft driven by the main motor to rotate, a lifting tooth shaft parallel to the main shaft, a first lifting tooth transmission assembly connected between the main shaft and the lifting tooth shaft, and a second lifting tooth transmission assembly connected between the lifting tooth shaft and a lifting tooth connecting part of the tooth frame; the first lifting tooth transmission assembly comprises a driving belt pulley fixed on the main shaft, a driven belt pulley fixed at one end of the lifting tooth shaft, and a transmission belt connected to the peripheries of the driving belt pulley and the driven belt pulley; the second lifting tooth transmission assembly comprises a lifting tooth eccentric wheel and a lifting tooth connecting rod, the lifting tooth eccentric wheel is fixed at the other end of the lifting tooth shaft, one end of the lifting tooth connecting rod is rotatably sleeved on the periphery of the lifting tooth eccentric wheel, and the other end of the lifting tooth connecting rod is hinged with the lifting tooth connecting part of the tooth frame.

As described above, the sewing machine of the present invention, which uses the same driving source to feed and cut thread, has the following advantages:

The application adopts the same feeding and thread cutting driving source to drive the feeding mechanism and the thread cutting mechanism, thereby realizing feeding and thread cutting; the thread cutting clutch assembly is arranged in the thread cutting mechanism, so that the thread cutting mechanism does not act in the normal sewing feeding process, and the feeding and thread cutting are not interfered; and when cutting the thread, the feeding thread cutting driving source drives the movable cutter to move through the driving crank, the engaged thread cutting clutch assembly and the thread cutting transmission assembly in sequence, so that the thread cutting is realized, namely, the thread cutting power is derived from the feeding thread cutting driving source and is independent of other driving sources in the sewing machine, thereby simplifying the structure and shortening the transmission chain.

Drawings

FIG. 1 is a schematic view of a sewing machine according to the present application.

Fig. 2 is a schematic view of a structure of the sewing machine according to the present application when a swing type lifter type is provided.

Fig. 3 is a schematic view of a structure of the sewing machine according to the present application when a rotary type lifter is provided.

Fig. 4 is a schematic structural diagram of a first embodiment of an independent feeding and trimming module according to the present application.

Fig. 5 is an exploded view of fig. 4, omitting the integrated mounting base.

Fig. 6 is a left side view of fig. 4, omitting the integrated mounting base.

Fig. 7 is a schematic distribution diagram of a working area of a feeding arm in the first embodiment of the independent feeding and trimming module.

Fig. 8 is a schematic diagram of a wire cutting clutch assembly in a separated state in a first embodiment of the independent feeding wire cutting module.

Fig. 9 is a schematic view of a wire cutting clutch assembly in an engaged state in a first embodiment of a self-contained feed wire cutting module.

Fig. 10a to 10d are schematic diagrams of four motion trajectories of the feeding teeth in the first embodiment of the independent feeding scissor module.

FIG. 11 is a schematic view of the position of the feeder arm and the feeder link in the first embodiment of the independent feeder scissor module.

Fig. 12a to 12c are three distribution diagrams of the cutting working area of the feeding arm in the first embodiment of the independent feeding cutting module.

Fig. 13 is a schematic structural diagram of a second embodiment of an independent feeding and trimming module according to the present application.

Fig. 14 is a left side view of fig. 13.

Fig. 15 is a schematic diagram of connection between a module driving source and a feeding mechanism in a second embodiment of the independent feeding scissor wire module.

Fig. 16 is a schematic diagram of the connection between the module driving source and the wire cutting mechanism in the second embodiment of the independent feeding wire cutting module.

Fig. 17 is a schematic distribution diagram of a working area of a feeding arm in a second embodiment of the independent feeding and trimming module.

Fig. 18 is a schematic view of a wire cutting clutch assembly in an engaged state in a second embodiment of a self-contained feed wire cutting module.

Fig. 19a to 19d are schematic diagrams of four motion trajectories of the feeding teeth in the second embodiment of the independent feeding scissor module.

FIG. 20 is a schematic view of the position of a feeder arm and feeder link in a second embodiment of an independent feeder scissor module.

Fig. 21a to 21c are three distribution diagrams of the cutting working area of the feeding arm in the second embodiment of the independent feeding cutting module.

Description of element reference numerals

10. Integrated mounting base

101. Mounting main board

102. Motor mounting plate

103. Feeding support part

104. Wire cutting support part

20. Module driving source

21. Driving motor

30. Feeding mechanism

31. Tooth rack

311. Feeding connecting part

312. Lifting tooth connecting part

32. Feeding tooth

33. Driving crank

331. Feeding arm

332. Wire cutting arm

34. Feeding connecting rod

35. Feeding shaft

36. Feeding crank

37. Dental frame base

371. Feeding connecting arm

40. Thread cutting mechanism

41. Movable knife

42. Shearing shaft

43. Thread cutting ball

44. Wire cutting driving piece

441. Wire cutting driving arm

442. Wire cutting connecting arm

443. Reset arm

45. Fixed knife

46. Wire cutting crank

47. Wire cutting connecting rod

48. Movable knife rest

49. Reset torsion spring

50. Tooth lifting mechanism

51. Main shaft

52. Lifting shaft

53. Lifting tooth eccentric wheel

54. Lifting tooth crank

55. Lifting tooth connecting rod

56. Fork-shaped crank for lifting tooth

57. Lifting tooth sliding block

58. Driving belt wheel

59. Driven belt pulley

510. Transmission belt

60. Bottom plate

Detailed Description

Further advantages and effects of the present invention will become apparent to those skilled in the art from the disclosure of the present invention, which is described by the following specific examples.

It should be understood that the structures, proportions, sizes, etc. shown in the drawings are for illustration purposes only and should not be construed as limiting the invention to the extent that it can be practiced, since modifications, changes in the proportions, or adjustments of the sizes, which are otherwise, used in the practice of the invention, are included in the spirit and scope of the invention which is otherwise, without departing from the spirit or scope thereof. Also, the terms such as "upper," "lower," "left," "right," "middle," and "a" and the like are used herein for descriptive purposes only and not for purposes of limitation, and are intended to limit the scope of the invention as defined by the claims and the relative terms thereof as construed as corresponding to the claims.

The application provides a sewing machine which adopts the same driving source to feed and cut threads. For convenience of description, in the following embodiments, the following directions are defined as follows: the longitudinal direction of the sewing machine is defined as the left-right direction, the direction toward the head of the sewing machine is the left direction, and the direction toward the tail of the sewing machine is the right direction, and the left-right direction is 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 moving direction of the sewing material is defined as the front direction when the sewing machine is forward sewing.

As shown in fig. 1 and 3 to 6, or as shown in fig. 1 and 13 to 16, the sewing machine according to the present application, which uses the same driving source for feeding and cutting thread, includes a feeding and thread cutting driving source 20, a feeding mechanism 30, and a thread cutting mechanism 40. The feeding mechanism 30 includes a frame 31, a feeding tooth 32 fixed on an upper end surface of the frame 31, a driving crank 33 driven by the feeding wire cutting driving source 20 to rotate, and a feeding transmission unit, wherein a feeding connecting portion 311 is arranged at a front end of the frame 31, a lifting connecting portion 312 is arranged at a rear end of the frame 31, a feeding arm 331 extends from the driving crank 33, and the feeding transmission unit is connected between the feeding arm 331 and the feeding connecting portion 311 of the frame 31 in a transmission manner. The thread cutting mechanism 40 comprises a movable knife 41, a thread cutting arm 332 driven to rotate by the feeding thread cutting driving source 20, a thread cutting shaft 42 which can rotate around the axis of the thread cutting arm and extend left and right, a thread cutting clutch assembly and a thread cutting transmission assembly which is connected between the thread cutting shaft 42 and the movable knife 41 in a transmission manner, wherein the thread cutting clutch assembly comprises thread cutting balls 43 and a thread cutting driving piece 44 fixed at the right end of the thread cutting shaft 42, and a thread cutting driving arm 441 extends out of the thread cutting driving piece 44; the thread cutting ball 43 is rotatably installed on the thread cutting arm 332 and the thread cutting driving arm 441 is provided with a thread cutting sliding groove surface, or the thread cutting ball 43 is rotatably installed on the thread cutting driving arm 441 and the thread cutting arm 332 is provided with a thread cutting sliding groove surface; in the following embodiment, taking the example that the thread cutting ball 43 is rotatably mounted on the thread cutting arm 332, the thread cutting driving arm 441 extends from the thread cutting driving member 44.

Preferably, both the wire cutting arm 332 and the driving crank 33 are driven to rotate by the feeding wire cutting driving source 20, and both the wire cutting arm 332 and the driving crank 33 may be separate pieces, fixed on a motor shaft of the module driving source 20 by screws, or the wire cutting arm 332 is fixed on the driving crank 33. In the embodiment described below, the wire cutting arm 332 integrally extends from the outer periphery of the drive crank 33.

In the process of the feeding and trimming driving source 20 driving the driving crank 33 to rotate, as shown in fig. 7 or 17, the angle of the feeding arm 331 has a feeding working area X1 and a trimming working area X2 which are independent of each other, and the angles of the two ends of the feeding working area X1 are respectivelyAnd/>The angles of the two ends of the cutting working area X2 are respectively/>And/>In the forward direction of the drive motor 21 when the sewing machine cuts thread,/>Thus, the angle range of the feeding working area X1 of the feeding arm 331 is/>The angle range of the trimming working area X2 of the feeding arm 331 is/>And the angle of the feeding arm 331 also has an idle zone X3 distributed between the feeding working zone X1 and the cutting working zone X2, and the angle range of the idle zone X3 of the feeding arm 331 is/>

When the sewing machine is in normal sewing, the feeding and thread cutting driving source 20 drives the driving crank 30 to rotate, and the feeding arm 331 rotates together with the driving crank 30. When the feeding arm 331 of the driving crank 33 is driven by the feeding thread cutting driving source 20 to run in the feeding working area X1, the feeding arm 331 drives the tooth frame 31 to reciprocate back and forth through the feeding transmission unit, the feeding tooth 32 reciprocates back and forth synchronously with the tooth frame 31, feeding action is performed, the sewing machine has an effective needle pitch, and the effective needle pitch comprises a positive needle pitch corresponding to the forward sewing state of the sewing machine and a negative needle pitch corresponding to the backward sewing state of the sewing machine; the wire cutting ball 43 is separated from the wire cutting sliding groove surface on the wire cutting driving arm 441, as shown in fig. 8, so that the wire cutting clutch assembly is in a separated state, that is, the force is not transmitted to the wire cutting transmission assembly, and the wire cutting mechanism 40 does not execute the wire cutting action.

When the sewing machine needs to cut the thread, the feeding and thread cutting driving source 20 drives the feeding arm 331 to positively rotate from the current angle in the feeding working area X1 to the initial angle of the thread cutting working area X2Then along the forward rotation to the end point angle/>, of the cutting working area X2From/>, at the feed arm 331Forward turn to/>In this process, namely, when the feeding arm 331 runs in the thread cutting working area X2, the thread cutting ball 43 gradually approaches the thread cutting sliding groove surface of the thread cutting driving arm 441 until contacting, as shown in fig. 9 or fig. 18, the thread cutting clutch component is in an engaged state and transmits power, then the feeding arm 331 contacts with the thread cutting sliding groove surface of the thread cutting driving arm 441 through the thread cutting ball 43 to push the thread cutting driving piece 44, namely, drives the thread cutting shaft 42 to rotate, and drives the movable knife 41 to move through the thread cutting transmission component, so that the thread cutting mechanism 40 automatically cuts threads.

Therefore, the application adopts the same feeding and thread cutting driving source 20 to drive the feeding mechanism and the thread cutting mechanism, thereby realizing feeding and thread cutting; the thread cutting clutch assembly is arranged in the thread cutting mechanism 40, so that the thread cutting mechanism 40 does not act in the normal sewing feeding process, and the feeding and thread cutting are ensured not to interfere; and, when cutting the thread, the feeding thread cutting driving source 20 drives the movable knife 41 to move sequentially through the driving crank 33, the engaged thread cutting clutch assembly and the thread cutting transmission assembly, so that the thread cutting is realized, namely, the thread cutting power is derived from the feeding thread cutting driving source 20 and is not dependent on other driving sources in the sewing machine, thereby simplifying the structure and shortening the transmission chain.

Further, as shown in fig. 1, the sewing machine further includes an integrated mounting base 10, and the feeding thread cutting driving source 20, the feeding mechanism 30 and the thread cutting mechanism 40 are mounted on the integrated mounting base 10 independently of the remaining driving sources in the sewing machine. Thus, the integrated mounting base 10, the feeding and thread cutting driving source 20, the feeding mechanism 30 and the thread cutting mechanism 40 are integrated into one independent functional module, the functional module is defined as an independent feeding and thread cutting module, the independent feeding and thread cutting module integrates the feeding function and the automatic thread cutting function, and the feeding mechanism 30 and the thread cutting mechanism 40 are independently modularized and independent of other functional mechanisms in the sewing machine. The independent feeding and thread cutting driving source 20 is adopted to independently drive feeding and thread cutting, and the power sources of feeding and thread cutting are independent of other functional mechanisms in the sewing machine, so that the structures of the feeding mechanism 30 and the thread cutting mechanism 40 are simplified, the respective transmission chains of the feeding mechanism 30 and the thread cutting mechanism 40 are effectively shortened, the occupied space is reduced, and the interference to the installation and arrangement of other functional mechanisms in the sewing machine is avoided as much as possible. And through the installation and the disassembly of the integrated installation base 10 in the sewing machine, the installation and the disassembly of the whole independent feeding thread cutting module in the sewing machine are realized, the rapid adapting installation of the independent feeding thread cutting module in various types of sewing machines is realized, and the compatibility is strong, namely, the novel design platform of the sewing machine is developed.

Preferably, as shown in fig. 1, the feeding and trimming driving source 20 is a driving motor 21, and a driving crank 33 is fixed on a motor shaft of the driving motor 21 through a fastener such as a screw; the drive motor 21 is preferably a stepping motor. The integrated mounting base 10 has a horizontally disposed mounting main board 101 and a motor mounting board 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 fasteners such as screws, the driving motor 21 is fixed to the right end side of the motor mounting board 102 by fasteners such as screws, and the motor shaft of the driving motor 21 is inserted into the motor mounting board 102.

In the independent feeding thread trimming module, the independent feeding thread trimming module is provided with a plurality of different embodiments based on thread trimming transmission assemblies and feeding transmission units with different structures. Two preferred embodiments of the independent feed scissor wire module are provided below.

Independent feeding and thread cutting module embodiment one

As shown in fig. 3 to 6, the feed transmission unit includes a feed link 34, a feed shaft 35 rotatable about its own axis and extending in the left-right axial direction, a feed crank 36 fixed to the right end of the feed shaft 35, and a rack mount 37 fixed to the left end of the feed shaft 35; the integrated mounting base 10 further includes a feed support portion 103 integrally extending from the mounting main plate 101, and the feed shaft 35 is rotatably supported in the feed support portion 103 of the integrated mounting base 10 by means of a bearing, a bushing, or the like; the two ends of the feeding connecting rod 34 are respectively connected with the feeding arm 331 and the feeding crank 36 in a rotating way, namely hinged, and the dental frame seat 37 is connected with the feeding connecting part 311 of the dental frame 31; the effective length of the feed arm 331 is less than the effective length of the feed link 34. In addition, in the left-right direction, the feed crank 36 is disposed on the right side of the feed support portion 103, the rack mount 37 is disposed on the left side of the feed support portion 103, and the rotational connection, i.e., the articulation, is achieved between one end of the feed link 34 and the outer end of the feed arm 331, and between the other end of the feed link 34 and the feed crank 36 by pins and bearings extending in the left-right axial direction, the bearings being fitted between the pins and the ends of the feed link 34.

When the sewing machine is in normal sewing, a motor shaft of the driving motor 21 swings reciprocally in an angle range, the feeding arm 331 of the driving crank 33 is driven to swing reciprocally in an angle range in the feeding working area X1, the feeding shaft 35 is driven to swing through the feeding connecting rod 34 and the feeding crank 36, and then the dental framework 31 and the feeding teeth 32 are driven to reciprocate back and forth through the dental framework seat 37 to feed. By adjusting the swing angle range of the driving motor 21, that is, the swing range of the feeding arm 331 of the driving crank 33 in the feeding working area X1, the effective needle pitch of the sewing machine is further adjusted, and the adjustment of the feeding needle pitch is realized, that is, the movement track of the feeding teeth 32 is adjusted. Such as: the feed tooth 32 may be provided with an elliptical motion profile as shown in fig. 10a, or the feed tooth 32 may be provided with a near vertical motion profile as shown in fig. 10b, or the feed tooth 32 may be provided with a far vertical motion profile as shown in fig. 10c, or the feed tooth 32 may be provided with a rectangular motion profile as shown in fig. 10 d. Thus, the embodiment one of the independent feeding thread cutting module has the functions of step-by-step adjustment of needle pitch, reverse stitching switching, feeding track switching, pattern stitching and the like.

Preferably, as shown in fig. 3 to 6, the integrated mounting base 10 further includes a wire cutting support portion 104 integrally extended from the mounting main plate 101, and the wire cutting shaft 42 is rotatably supported in the wire cutting support portion 104 of the integrated mounting base 10 by means of a bearing, a bushing, or the like; the thread cutting arms 332 on the drive crank 33 are distributed in a staggered manner with the feeding arms 331 in the circumferential direction. Of course, in other embodiments, the wire cutting arm 332 on the driving crank 33 and the feeding arm 331 may be circumferentially coincident, and may be the same arm.

Further, the wire cutting mechanism 40 may be a single-action knife structure or a double-action knife structure. In the first embodiment of the independent feeding thread cutting module, as shown in fig. 3 and 4, the thread cutting mechanism 40 is of a single-acting cutter structure, the thread cutting mechanism 40 further comprises a fixed cutter 45 fixedly arranged, the thread cutting transmission assembly comprises a thread cutting crank 46 fixed on the thread cutting shaft 42, a thread cutting connecting rod 47 and a rotatable movable cutter frame 48, two ends of the thread cutting connecting rod 47 are respectively hinged with the thread cutting crank 46 and the movable cutter frame 48, and the movable cutter 41 is fixed on the movable cutter frame 48.

Preferably, as shown in fig. 3 and 4, the wire cutting mechanism 40 further includes a reset torsion spring 49 sleeved on the wire cutting shaft 42, and both ends of the reset torsion spring 49 are respectively connected with the integrated mounting base 10 and the wire cutting crank 46. After the trimming is finished, the driving motor 21 reversely rotates to drive the feeding arm 331 to move from the end point angle of the trimming working area X2The current angle in the feeding working area X1 before the wire cutting is reversed, and under the action of the reset torsion spring 49, the wire cutting crank 46 is driven to reset, namely the wire cutting shaft 42, the wire cutting connecting rod 47, the movable cutter frame 48 and other parts are driven to reset respectively; also, the return torsion spring 49 also maintains the wire cutting crank 46 in its initial position when wire cutting is not required. More preferably, as shown in fig. 8 and 9, a reset arm 443 extends from the wire cutting driving member 44, the reset arm 443 and the wire cutting driving arm 441 are distributed in a staggered manner in the circumferential direction, and the outer circumferential surface of the reset arm 443 is provided with a section of forced reset surface; the feeding arm 331 is driven by the driving motor 21 from the end point angle/>, of the trimming working area X2When the reversing starts, the forced reset surface on the reset arm 443 is in contact fit with the thread cutting balls 43, the thread cutting balls 43 push the reset arm 443 to reset, so that the thread cutting driving piece 44 is driven to forcibly reset, all parts in the thread cutting mechanism 40 are driven to forcibly reset, the risk that the movable cutter 41 cannot reset smoothly due to the fact that the movable cutter 41 is blocked by thread is avoided, the movable cutter 41 can be prevented from being blocked by the thread, and the next smooth automatic thread cutting is ensured.

Further, in the first embodiment of the independent feeding and trimming module, as shown in fig. 6, the effective length of the feeding arm 331 is smaller than the effective length of the feeding link 34; the effective length of the feed arm 331 is: the distance between the center of the motor shaft of the driving motor 21 and the rotation centers of the feeding arm 331 and the feeding link 34; the effective length of the feed link 34 refers to: the distance between the center of rotation of the feed arm 331 and the feed link 34 and the center of rotation of the feed link 34 and the feed crank 36. Therefore, the feeding mechanism 30 in the first embodiment of the independent feeding and trimming module adopts a structure of a short crank and a long connecting rod. The following configuration is performed on the position angles of the feeding arm 331 and the feeding connecting rod 34, so that the moving distance of the feeding teeth 32 in the front-rear direction in the wire cutting process is as small as possible, the wire cutting effect of the short wire ends is realized, and the experience of customers is improved.

Specifically, as shown in fig. 11, the center of rotation C of the feeding arm 331 is taken as the center of the circle, the effective length CD of the feeding arm 331 is taken as the radius of the circle O1, the point C is the center of the motor shaft of the driving motor 21, and the point D is the center of rotation of the feeding arm 331 and the feeding link 34; the hinge point B of the feeding connecting rod 34 and the feeding crank 36 is used as a center, the effective length BD of the feeding connecting rod 34 is used as a radius to be used as a circle O2, and the point A is used as the center of the feeding shaft 35. Circles O1 and O2 are substantially coincident within ± β angles of the collinear position of the feed arm 331 and feed link 34. The angle of the feeding arm 331 is shown as being when the feeding arm 331 is collinear with the feeding link 34Then the feed arm 331 is at/>During this range of motion, the feed crank 36 remains substantially stationary, i.e., the feed dog 32 is displaced in the fore-aft direction by a small amount and is not fed substantially. Namely: when the angle of the feed arm 331 is at/>When the range is within, the independent feeding thread cutting module enables the sewing machine to have a small needle distance; in this embodiment, when the angle of the feeding arm 331 is at/>Within this range, the independent feed scissors module makes the movement amount of the feed dog 32 in the front-rear direction not more than 1mm. Based on this, the trimming working area X2 of the feeding arm 331 is set at/>Within this range, the distance of movement of the feed dog 32 in the front-rear direction during the thread cutting process is made very small; the trimming working area X2 of the feeding arm 331 may be set as: /(I) Thus, the wire cutting working area X2 of the feeding arm 331 can have the following three embodiments.

Embodiment one of the cutting work area X2 of the feeding arm 331 as shown in figure 12a,

In a second embodiment of the cutting work X2 of the feeding arm 331 as shown in figure 12b,

A third embodiment of the cutting working area X2 of the feeding arm 331 is shown in figure 12c,

Further, when the feed arm 331 is collinear with the feed link 34, the feed dog 32 is located at a front limit position within the range of the back and forth reciprocating movement thereof, and there is a minimum limit distance between the feed dog 32 and the tooth slot front end of the needle plate. Or when the feeding arm 331 is collinear with the feeding link 34, the feeding tooth 32 is located at the rear limit position within the forward and backward reciprocating movement range thereof, and the feeding tooth 32 has the minimum limit distance from the rear end of the tooth slot of the needle plate.

Independent feeding thread cutting module embodiment II

As shown in fig. 13 to 15, the feed transmission unit includes a feed link 34, a feed shaft 35 rotatable about its own axis and extending in the left-right axial direction, a dental frame mount 37 fixed to the feed shaft 35, and a feed connection arm 371 fixedly connected to the dental frame mount 37, the feed shaft 35 being rotatably supported in the integrated mounting base 10, both ends of the feed link 34 being rotatably connected, i.e., hinged, with the feed arm 331 and the feed connection arm 371, respectively, the dental frame mount 37 being connected to the feed connection portion 311 of the dental frame 31; the effective length of the feed arm 331 is greater than the effective length of the feed link 34. The feeding connecting arm 371 and the dental frame seat 37 can be in an integrated structure, and the feeding connecting arm 371 is integrally arranged on the periphery of the dental frame seat 37; or a separate piece is arranged between the feeding connecting arm 371 and the dental frame seat 37, and the feeding connecting arm 371 and the dental frame seat 37 are fixedly connected through screws.

In the second embodiment of the independent feeding and thread cutting module, the thread cutting arm 332 and the feeding arm 331 on the driving crank 33 are the same arm, the outer end of the common arm, the feeding connecting rod 34 and the thread cutting ball 43 are coaxially connected through a pin extending from left to right, the feeding connecting rod 34 is distributed on the left side of the common arm, and the thread cutting ball 43 is distributed on the right side of the common arm. The wire cutting mechanism 40 is of a single-acting knife structure, the wire cutting mechanism 40 further comprises a fixed knife 45 which is fixedly arranged, a wire cutting connecting arm 442 extends out of the wire cutting driving piece 44, a wire cutting driving arm 441 and the wire cutting connecting arm 442 are distributed in a circumferential dislocation mode, the wire cutting driving assembly comprises a wire cutting connecting rod 47 and a rotatable movable knife rest 48, two ends of the wire cutting connecting rod 47 are hinged to the wire cutting connecting arm 442 and the movable knife rest 48 respectively, and the movable knife 41 is fixed on the movable knife rest 48. Of course, in other embodiments, the wire cutting mechanism 40 may also employ a double-acting knife structure.

When the sewing machine is in normal sewing, a motor shaft of the driving motor 21 swings back and forth in an angle range, the feeding arm 331 of the driving crank 33 is driven to swing back and forth in an angle range in the feeding working area X1, namely the feeding arm 331 runs in the feeding working area X1, at the moment, the feeding connecting rod 34 drives the feeding shaft 35 to swing, and then the dental shelf 31 and the feeding teeth 32 are driven to reciprocate back and forth through the dental shelf seat 37, and the feeding teeth 32 feed normally; the thread cutting ball 43 is separated from the thread cutting sliding groove surface of the thread cutting driving arm 441, so that the thread cutting clutch assembly is in a separated state and does not transmit power, and the thread cutting mechanism 40 does not execute thread cutting action. When the feeding arm 331 of the driving crank 33 runs in the feeding working area X1, the independent feeding thread cutting module enables the sewing machine to have an effective stitch length, and the effective stitch length comprises a positive stitch length corresponding to a positive stitch state of the sewing machine and a negative stitch length corresponding to a reverse stitch state of the sewing machine. Further, by adjusting the swing angle range of the driving motor 21, that is, the swing range of the feeding arm 331 of the driving crank 33 in the feeding working area X1, the effective needle pitch of the sewing machine is further adjusted, and the adjustment of the feeding needle pitch is realized, that is, the movement track of the feeding teeth 32 is adjusted. Such as: the feed tooth 32 may be provided with an elliptical motion profile as shown in fig. 19a, or the feed tooth 32 may be provided with a near vertical motion profile as shown in fig. 19b, or the feed tooth 32 may be provided with a far vertical motion profile as shown in fig. 19c, or the feed tooth 32 may be provided with a rectangular motion profile as shown in fig. 19 d. Thus, the embodiment one of the independent feeding thread cutting module has the functions of step-by-step adjustment of needle pitch, reverse stitching switching, feeding track switching, pattern stitching and the like.

When the wire is needed to be cut, the driving motor 21 drives the feeding arm 331 to rotate forward from the current angle in the feeding working area X1 to the initial angle of the wire cutting working area X2Then along the forward rotation to the end point angle/>, of the cutting working area X2From/>, at the feed arm 331Forward turn to/>In this process, the feeding arm 331 runs in the wire cutting working area X2, the wire cutting ball 43 gradually approaches the wire cutting sliding groove surface of the wire cutting driving arm 441 until contacting, as shown in fig. 18, the wire cutting clutch assembly is in an engaged state and transmits power, then the feeding arm 331 contacts the wire cutting sliding groove surface of the wire cutting driving arm 441 through the wire cutting ball 43 to push the wire cutting driving piece 44 in a matched manner, and then the wire cutting connecting rod 47 and the moving knife frame 48 drive the moving knife 41 to move, so that the wire cutting mechanism 40 automatically cuts wires.

Further, the wire cutting mechanism 40 further includes a return torsion spring 49 sleeved on the wire cutting shaft 42, and two ends of the return torsion spring 49 are respectively connected with the integrated mounting base 10 and the wire cutting connection arm 442. After the trimming is finished, the driving motor 21 reversely rotates to drive the feeding arm 331 to move from the end point angle of the trimming working area X2The current angle in the feeding working area X1 before the wire cutting is reversed, and under the action of the reset torsion spring 49, the wire cutting driving piece 44 is driven to reversely rotate and reset, namely the wire cutting shaft 42, the wire cutting connecting rod 47, the movable knife rest 48 and other parts are driven to reset respectively; also, the reset torsion spring 49 maintains the wire cutting drive 44 in its initial position when cutting wire is not required. More preferably, as shown in fig. 18, a reset arm 443 is further extended from the wire cutting driving member 44, the reset arm 443 and the wire cutting driving arm 441 are distributed in a staggered manner in the circumferential direction, and the outer circumferential surface of the reset arm 443 has a section of forced reset surface; the feeding arm 331 is driven by the driving motor 21 from the end point angle/>, of the trimming working area X2When the reversing starts, the forced reset surface on the reset arm 443 is in contact fit with the thread cutting balls 43, the thread cutting balls 43 push the reset arm 443 to reset, so that the thread cutting driving piece 44 is driven to forcibly reset, all parts in the thread cutting mechanism 40 are driven to forcibly reset, the risk that the movable cutter 41 cannot reset smoothly due to the fact that the movable cutter 41 is blocked by thread is avoided, the movable cutter 41 can be prevented from being blocked by the thread, and the next smooth automatic thread cutting is ensured.

Further, in the second embodiment of the independent feeding and trimming module, as shown in fig. 15, the effective length of the feeding arm 331 is greater than the effective length of the feeding link 34; the effective length of the feed arm 331 is: the distance between the center of the motor shaft of the driving motor 21 and the rotation centers of the feeding arm 331 and the feeding link 34; the effective length of the feed link 34 refers to: the distance between the rotational centers of the feed arm 331 and the feed link 34 and the rotational centers of the feed link 34 and the feed link arm 371. Therefore, the feeding mechanism 30 in the second embodiment of the independent feeding and trimming module adopts a long crank-short link structure. The following configuration is performed on the position angles of the feeding arm 331 and the feeding connecting rod 34, so that the moving distance of the feeding teeth 32 in the front-rear direction in the wire cutting process is as small as possible, the wire cutting effect of the short wire ends is realized, and the experience of customers is improved.

Specifically, as shown in fig. 20, the point E is the center of the motor shaft of the driving motor 21, and the point F is the rotation centers of the feeding arm 331 and the feeding link 34, 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 as the circle O3; the circle O4 is made with the hinge point G of the feed link 34 and the feed link arm 371 as the center and the effective length FG of the feed link 34 as the radius. Circle O3 and circle O4 are substantially coincident within ± β angles of the collinear position of feed arm 331 and feed link 34. The angle of the feeding arm 331 is shown as being when the feeding arm 331 is collinear with the feeding link 34The feeding arm 331 is atIn this range of motion, the four-bar mechanism consisting of the drive crank 33, the feed link 34, the rack mount 37 and the rack 31 forms an intermittent mechanism, and a dead time occurs, that is, the position change of the hinge point of the feed link 34 and the feed link arm 371 of the rack mount 37 is small, the position angle change of the rack mount 37 is small, the rack mount 37 is kept substantially stationary, that is, the displacement amount of the feed dog 32 in the front-rear direction is small, and the feed is not substantially performed. Namely: when the angle of the feed arm 331 is at/>When the range is within, the independent feeding thread cutting module enables the sewing machine to have a small needle distance; in this embodiment, when the angle of the feeding arm 331 is at/>Within this range, the independent feed scissors module makes the movement amount of the feed dog 32 in the front-rear direction not more than 1mm. Based on this, the trimming working area X2 of the feeding arm 331 is set at/>Within this range, the distance of movement of the feed dog 32 in the front-rear direction during the thread cutting process is made very small; the trimming working area X2 of the feeding arm 331 may be set as: /(I) Thus, the wire cutting working area X2 of the feeding arm 331 can have the following three embodiments.

Embodiment one of the cutting work area X2 of the feeding arm 331 as shown in figure 21a,/>

In a second embodiment of the cutting work X2 of the feeding arm 331 as shown in figure 21b,

A third embodiment of the cutting working area X2 of the feeding arm 331 is shown in figure 21c,

Further, when the feed arm 331 is collinear with the feed link 34, the feed dog 32 is located at a front limit position within the range of the back and forth reciprocating movement thereof, and there is a minimum limit distance between the feed dog 32 and the tooth slot front end of the needle plate. Or when the feeding arm 331 is collinear with the feeding link 34, the feeding tooth 32 is located at the rear limit position within the forward and backward reciprocating movement range thereof, and the feeding tooth 32 has the minimum limit distance from the rear end of the tooth slot of the needle plate.

Further, in addition to the above-mentioned independent feeding thread cutting module, as shown in fig. 1 to 3, the sewing machine further includes a lifting-tooth driving source, a lifting-tooth mechanism 50 and a bottom plate 60 fixedly arranged, and the lifting-tooth mechanism 50 is in transmission connection between the lifting-tooth driving source and a lifting-tooth connecting portion 312 at the rear end of the frame 31. The installation and the disassembly of the integrated installation base 10 in the sewing machine are realized, so that the installation and the disassembly of the whole independent feeding thread cutting module in the sewing machine are realized, the independent feeding thread cutting module is used as an independent functional mechanism to be quickly and adaptively installed in the sewing machines of various types, interference with other functional mechanisms of the sewing machine is avoided, and the compatibility is strong. Preferably, the integrated mounting base 10 is detachably connected with the bottom plate 60 through a plurality of screws, so that the integrated mounting base is convenient to assemble and disassemble. As shown in fig. 1, the individual feed scissor wire modules are distributed on the left side of the base plate 60 near the sewing machine head.

Further, as shown in fig. 2 or 3, the lifting-tooth driving source is a main motor of the sewing machine, the lifting-tooth mechanism 50 includes a main shaft 51 driven to rotate by the main motor, a lifting-tooth shaft 52 parallel to the main shaft 51, a first lifting-tooth transmission assembly connected between the main shaft 51 and the lifting-tooth shaft 52, and a second lifting-tooth transmission assembly connected between the lifting-tooth shaft 52 and the lifting-tooth connecting portion 312 of the frame 31, and both the main shaft 51 and the lifting-tooth shaft 52 extend axially in the left-right direction.

When the independent feeding thread cutting module is matched with the swinging type thread lifting machine, as shown in fig. 2, the first thread lifting transmission assembly comprises a thread lifting eccentric wheel 53 fixed on a main shaft 51, a thread lifting crank 54 fixed at the right end of a thread lifting shaft 52 and a thread lifting connecting rod 55, the upper end of the thread lifting connecting rod 55 is rotatably sleeved on the periphery of the thread lifting eccentric wheel 53, and the lower end of the thread lifting connecting rod 55 is hinged with the thread lifting crank 54; the second lifting tooth transmission assembly comprises a lifting tooth fork-shaped crank 56 fixed at the left end of the lifting tooth shaft 52 and a lifting tooth sliding block 57 hinged with a lifting tooth connecting part 312 of the tooth frame 31, wherein the lifting tooth fork-shaped crank 56 is provided with a lifting tooth sliding groove in sliding fit with the lifting tooth sliding block 57. The main motor drives the main shaft 51 to rotate, the main shaft 51 drives the lifting tooth shaft 52 to swing through the first lifting tooth transmission assembly, the lifting tooth shaft 52 drives the lifting tooth fork-shaped crank 56 to swing up and down through the second lifting tooth transmission assembly, and accordingly up-and-down reciprocating motion of the tooth frame 31 and the feeding tooth 32 is achieved, and the lifting tooth action is executed. The up-and-down lifting motion and the front-and-back feeding motion of the feeding teeth 32 together form a feeding track of the feeding teeth 32. Of course, in other embodiments, the second lifter transmission assembly may employ other configurations of transmission pairs.

When the independent feeding thread cutting module is matched with the rotary type thread lifting machine, as shown in fig. 3, the first thread lifting transmission assembly comprises a driving belt pulley 58 fixed on the main shaft 51, a driven belt pulley 59 fixed at the right end of the thread lifting shaft 52, and a transmission belt 510 connected to the peripheries of the driving belt pulley 58 and the driven belt pulley 59, wherein the rotation speed ratio of the driving belt pulley 58 to the driven belt pulley 59 is 1:1; the second lifting tooth transmission assembly comprises a lifting tooth eccentric wheel 53 fixed at the left end of the lifting tooth shaft 52 and a lifting tooth connecting rod 55, one end of the lifting tooth connecting rod 55 is rotatably sleeved on the periphery of the lifting tooth eccentric wheel 53, and the other end of the lifting tooth connecting rod 55 is hinged with a lifting tooth connecting part 312 of the tooth frame 31. The main motor drives the main shaft 51 to rotate, the main shaft 51 drives the lifting tooth shaft 52 to rotate through the first lifting tooth transmission assembly, and the lifting tooth shaft 52 drives the tooth frame 31 and the feeding tooth 32 to reciprocate up and down through the second lifting tooth transmission assembly so as to execute the lifting tooth action. The up-and-down lifting motion and the front-and-back feeding motion of the feeding teeth 32 together form a feeding track of the feeding teeth 32. Of course, in other embodiments, the second lifter transmission assembly may employ other configurations of transmission pairs.

In summary, the independent feeding thread trimming module and the sewing machine provided by the invention have the following advantages:

1. The independent feeding thread cutting module can be used as an independent unit module to be matched with various sewing machine models, has strong compatibility, and develops a new design platform of the sewing machine.

2. The independent feeding thread cutting module integrates the feeding mechanism 30 and the thread cutting mechanism 40, has simple structure, short transmission chain and small space for mounting the duty cycle, and does not interfere with other functional mechanisms of the sewing machine.

3. The same driving motor 21 is adopted for feeding and driving the wire cutting, and the feeding and the wire cutting are not interfered with each other.

4. By adjusting the output angle of the driving motor 21, the functions of needle pitch adjustment, backstitch switching, track switching of the feeding teeth 32, pattern sewing and the like can be realized, and the functions are comprehensive and the adaptability is wide.

5. The thread cutting mechanism 40 can be driven by the driving motor 21 to cut threads, and other driving sources in the sewing machine are not needed, so that independent modularization of the independent feeding thread cutting module is ensured.

In summary, the present invention effectively overcomes the disadvantages of the prior art and has high industrial utility value.

The above embodiments are merely illustrative of the principles of the present invention and its effectiveness, and are not intended to limit the invention. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is intended that all equivalent modifications and variations of the invention be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims (10)

1. A sewing machine for feeding and trimming threads by adopting the same driving source is characterized in that: comprises a feeding and thread cutting driving source (20), a feeding mechanism (30) and a thread cutting mechanism (40);

The feeding mechanism (30) comprises a dental framework (31), feeding teeth (32) fixed on the dental framework (31), a driving crank (33) driven by a feeding wire cutting driving source (20) to rotate and a feeding transmission unit, wherein a feeding arm (331) extends out of the driving crank (33), and the feeding transmission unit is in transmission connection between the feeding arm (331) and a feeding connecting part (311) of the dental framework (31);

The wire cutting mechanism (40) comprises a movable moving blade (41), a wire cutting arm (332) driven to rotate by a feeding wire cutting driving source (20), a wire cutting shaft (42) capable of rotating around the axis of the wire cutting arm, a wire cutting clutch assembly and a wire cutting transmission assembly connected between the wire cutting shaft (42) and the moving blade (41) in a transmission manner, wherein the wire cutting clutch assembly comprises a wire cutting ball (43) and a wire cutting driving piece (44) fixed on the wire cutting shaft (42), and a wire cutting driving arm (441) extends out of the wire cutting driving piece (44); the thread cutting ball (43) is rotatably arranged on the thread cutting arm (332) and the thread cutting driving arm (441) is provided with a thread cutting sliding groove surface, or the thread cutting ball (43) is rotatably arranged on the thread cutting driving arm (441) and the thread cutting arm (332) is provided with a thread cutting sliding groove surface;

In the process that the feeding and trimming driving source (20) drives the driving crank (33) to rotate, the angle of the feeding arm (331) is provided with a feeding working area and a trimming working area which are independent of each other: when the feeding arm (331) runs in a feeding working area, the sewing machine has an effective needle pitch, and the thread cutting ball (43) is separated from a thread cutting sliding groove surface; when the feeding arm (331) runs in the thread cutting working area, the thread cutting balls (43) are in contact fit with the thread cutting sliding groove surface.

2. The sewing machine of claim 1, wherein: the wire cutting mechanism (40) is of a single-acting cutter structure, the wire cutting mechanism (40) further comprises a fixed cutter (45) which is fixedly arranged, the wire cutting transmission assembly comprises a wire cutting crank (46) which is fixed on a wire cutting shaft (42), a wire cutting connecting rod (47) and a rotatable movable cutter frame (48), two ends of the wire cutting connecting rod (47) are respectively hinged with the wire cutting crank (46) and the movable cutter frame (48), and the movable cutter (41) is fixed on the movable cutter frame (48).

3. The sewing machine of claim 2, wherein: the thread cutting mechanism (40) further comprises a reset torsion spring (49) sleeved on the thread cutting shaft (42), one end of the reset torsion spring (49) is fixed, and the other end of the reset torsion spring is connected with the thread cutting crank (46).

4. The sewing machine of claim 1, wherein: the wire cutting mechanism (40) is of a single-acting knife structure, the wire cutting mechanism (40) further comprises a fixed knife (45) which is fixedly arranged, the wire cutting transmission assembly comprises a wire cutting connecting arm (442), a wire cutting connecting rod (47) and a rotatable moving knife rest (48) which extend from a wire cutting driving piece (44), two ends of the wire cutting connecting rod (47) are respectively hinged with the wire cutting connecting arm (442) and the moving knife rest (48), and the moving knife (41) is fixed on the moving knife rest (48).

5. The sewing machine of claim 4, wherein: the wire cutting mechanism (40) further comprises a reset torsion spring (49) sleeved on the wire cutting shaft (42), one end of the reset torsion spring (49) is fixed, and the other end of the reset torsion spring is connected with the wire cutting connecting arm (442).

6. The sewing machine of claim 1, wherein: when the thread cutting ball (43) is rotatably arranged on the thread cutting arm (332), a reset arm (443) extends out of the thread cutting driving piece (44), the reset arm (443) and the thread cutting driving arm (441) are distributed in a circumferential dislocation mode, and a forced reset surface on the reset arm (443) can be in contact fit with the thread cutting ball (43).

7. The sewing machine of claim 1, wherein: the feeding transmission unit comprises a feeding connecting rod (34), a feeding shaft (35) capable of rotating around the axis of the feeding connecting rod, a feeding crank (36) fixed at one end of the feeding shaft (35) and a dental frame seat (37) fixed at the other end of the feeding shaft (35), two ends of the feeding connecting rod (34) are respectively connected with a feeding arm (331) and the feeding crank (36) in a rotating way, and the dental frame seat (37) is connected with a feeding connecting part (311) of a dental frame (31); the effective length of the feeding arm (331) is smaller than that of the feeding connecting rod (34).

8. The sewing machine of claim 1, wherein: the feeding transmission unit comprises a feeding connecting rod (34), a feeding shaft (35) capable of rotating around the axis of the feeding connecting rod, a dental frame seat (37) fixed on the feeding shaft (35) and a feeding connecting arm (371) fixedly connected with the dental frame seat (37), wherein two ends of the feeding connecting rod (34) are respectively connected with the feeding arm (331) and the feeding connecting arm (371) in a rotating mode, and the dental frame seat (37) is connected with a feeding connecting part (311) of the dental frame (31); the effective length of the feeding arm (331) is greater than that of the feeding connecting rod (34).

9. The sewing machine of claim 1, wherein: the sewing machine is characterized by further comprising a lifting tooth driving source and a lifting tooth mechanism (50), wherein the lifting tooth driving source is a main motor of the sewing machine, and the lifting tooth mechanism (50) comprises a main shaft (51) driven to rotate by the main motor, a lifting tooth shaft (52) parallel to the main shaft (51), a first lifting tooth transmission assembly connected between the main shaft (51) and the lifting tooth shaft (52) and a second lifting tooth transmission assembly connected between the lifting tooth shaft (52) and a lifting tooth connecting part (312) of the tooth frame (31); the first lifting tooth transmission assembly comprises a lifting tooth eccentric wheel (53) fixed on the main shaft (51), a lifting tooth crank (54) fixed at one end of the lifting tooth shaft (52) and a lifting tooth connecting rod (55), one end of the lifting tooth connecting rod (55) is rotatably sleeved on the periphery of the lifting tooth eccentric wheel (53), and the other end of the lifting tooth connecting rod (55) is hinged with the lifting tooth crank (54); the second lifting tooth transmission assembly comprises a lifting tooth fork crank (56) fixed at the other end of the lifting tooth shaft (52) and a lifting tooth sliding block (57) hinged with a lifting tooth connecting part (312) of the tooth frame (31), and the lifting tooth fork crank (56) is internally provided with a lifting tooth sliding groove in sliding fit with the lifting tooth sliding block (57).

10. The sewing machine of claim 1, wherein: the sewing machine is characterized by further comprising a lifting tooth driving source and a lifting tooth mechanism (50), wherein the lifting tooth driving source is a main motor of the sewing machine, and the lifting tooth mechanism (50) comprises a main shaft (51) driven to rotate by the main motor, a lifting tooth shaft (52) parallel to the main shaft (51), a first lifting tooth transmission assembly connected between the main shaft (51) and the lifting tooth shaft (52) and a second lifting tooth transmission assembly connected between the lifting tooth shaft (52) and a lifting tooth connecting part (312) of the tooth frame (31); the first lifting tooth transmission assembly comprises a driving belt wheel (58) fixed on the main shaft (51), a driven belt wheel (59) fixed at one end of the lifting tooth shaft (52), and a transmission belt (510) connected to the peripheries of the driving belt wheel (58) and the driven belt wheel (59); the second lifting tooth transmission assembly comprises a lifting tooth eccentric wheel (53) fixed at the other end of the lifting tooth shaft (52) and a lifting tooth connecting rod (55), one end of the lifting tooth connecting rod (55) is rotatably sleeved on the periphery of the lifting tooth eccentric wheel (53), and the other end of the lifting tooth connecting rod (55) is hinged to a lifting tooth connecting part (312) of the tooth frame (31).