CN217418981U

CN217418981U - Driving mechanism of sewing machine

Info

Publication number: CN217418981U
Application number: CN202121437375.6U
Authority: CN
Inventors: 郏彬辉; 祝书伟; 郑吉�; 柯祥林
Original assignee: Jack Technology Co Ltd
Current assignee: Jack Technology Co Ltd
Priority date: 2021-06-25
Filing date: 2021-06-25
Publication date: 2022-09-13
Anticipated expiration: 2031-06-25

Abstract

The utility model provides a sewing machine's actuating mechanism belongs to sewing machine technical field. The sewing machine solves the technical problems of high production cost and the like of the sewing machine. The driving mechanism of the sewing machine comprises a double-output-shaft stepping motor, wherein a first thread cutting crank is arranged on an output shaft at one end of the double-output-shaft stepping motor, a second thread cutting crank is connected with a thread cutting assembly, the first thread cutting crank and the second thread cutting crank are matched to drive the first thread cutting assembly to cut threads, a thread loosening connecting rod is hinged to the second thread cutting crank, and the thread loosening connecting rod is connected with the thread loosening assembly to realize a thread loosening function; the output shaft of the other end of the double-output-shaft stepping motor is provided with a cam piece, the pressure lifting pin assembly is connected with a pressure lifting pin crank, the cloth feeding assembly is connected with a tooth adjusting lever, and the cam piece is provided with a first base part connected with the pressure lifting pin crank, a first convex part used for driving the pressure lifting pin assembly to automatically lift the pressure pin, a second base part connected with the tooth adjusting lever and a second convex part capable of driving the cloth feeding assembly to automatically adjust the tooth height. The utility model discloses in only used a driving piece, reduced sewing machine's manufacturing cost.

Description

Driving mechanism of sewing machine

Technical Field

The utility model belongs to the technical field of sewing machine, a sewing machine's actuating mechanism is related to.

Background

The sewing machine is a machine which uses one or more sewing threads to form one or more stitches on a sewing material so as to interweave or sew one or more layers of the sewing material; the sewing machine can sew fabrics such as cotton, hemp, silk, wool, artificial fiber and the like and products such as leather, plastic, paper and the like, and the sewed stitches are neat, beautiful, flat and firm, and have the advantages of high sewing speed, simple and convenient use and the like; most of sewing machines in the current market utilize electromagnets to realize functions of automatically lifting a presser foot, automatically cutting threads, automatically adjusting tooth height, supplying and the like, and one function uses one electromagnet, so that the installation is very troublesome.

Chinese patent (publication number: CN 209722475U; publication date: 2019-12-03) discloses an automatic presser foot lifting and thread loosening mechanism and a sewing machine; lift presser foot lax line cam and set up in the pivot of motor, the one end of keeping away from the pivot of motor on lifting presser foot lax line cam is provided with extension spring seat one, lift presser foot lax line roof and include bifurcation portion one, bifurcation portion two and bifurcation portion three, and lift the middle part of presser foot lax line roof and rotate the connection on the casing through lifting presser foot lax line round pin, bifurcation portion two's outer end is provided with extension spring seat two, be connected through the extension spring between extension spring seat one and the extension spring seat two and make the outer cylinder of extension spring seat two and lift presser foot lax line cam contact and be connected, bifurcation portion one's outer end is located the below of presser bar guide of presser foot subassembly, bifurcation portion three's outer end is located one side that the nail was assisted to the lax line of lax line subassembly.

The automatic presser foot lifting and thread loosening mechanism and the sewing machine disclosed in the above patent documents realize the automatic presser foot lifting and thread loosening functions by using one motor, but the functions of thread trimming, tooth height adjustment and the like cannot be realized by using the motor, so that the production cost of the sewing machine is increased.

Disclosure of Invention

The utility model discloses to the above-mentioned problem that prior art exists, provide a sewing machine's actuating mechanism, the utility model aims to solve the technical problem that: how to reduce the production cost of the sewing machine.

The purpose of the utility model can be realized by the following technical proposal:

a driving mechanism of a sewing machine comprises a bottom plate, a thread cutting assembly, a presser foot lifting assembly, a thread loosening assembly and a cloth feeding assembly, and is characterized in that the driving mechanism comprises a double-output-shaft stepping motor fixed on the lower side of the bottom plate, and a crank assembly capable of enabling the thread cutting assembly to perform automatic thread cutting action and enabling the thread loosening assembly to perform thread loosening action is arranged on an output shaft at one end of the double-output-shaft stepping motor; and a cam component which can enable the presser foot lifting component to carry out presser foot lifting action and can drive the cloth feeding component to adjust the tooth height is arranged on an output shaft at the other end of the double-output-shaft stepping motor.

In the driving mechanism of the sewing machine, the crank assembly comprises a first thread trimming crank fixedly arranged on an output shaft at one end of the double-output-shaft stepping motor; the trimming assembly is connected with a trimming crank II, a trimming pin shaft is arranged on one side of the trimming crank I, a trimming roller is sleeved on the trimming pin shaft, a sliding groove for the trimming roller to be slidably embedded into is formed in the trimming crank II, and one end of the trimming crank II is connected with the trimming assembly; and a thread loosening connecting rod is hinged to the thread shearing crank II and is connected with the thread loosening component.

In the above driving mechanism of the sewing machine, the cam assembly includes a cam member fixedly provided on an output shaft at the other end of the double-output-shaft stepping motor; the pressure foot lifting assembly is connected with a pressure foot lifting crankshaft, one end, far away from the pressure foot lifting assembly, of the pressure foot lifting crankshaft is fixedly provided with a pressure foot lifting crank, the outer side of the cam piece is provided with a first base part and a first convex part which can be connected with the pressure foot lifting crank, and the first convex part can drive the pressure foot lifting crank to swing; a tooth adjusting lever is sleeved on the crank shaft of the lifting and pressing foot, one end of the tooth adjusting lever is connected with the cloth feeding assembly, and a base part II and a convex part II which are connected with the other end of the tooth adjusting lever are arranged on the outer side of the cam piece.

The working principle is as follows: the positive rotation of the double-output-shaft stepping motor in the technical scheme can drive the first trimming crank to swing, when the first trimming crank swings to the position where the trimming pin shaft is embedded into the sliding groove of the second trimming crank, the second trimming crank can be driven to swing, so that the trimming assembly is driven to perform automatic trimming action, the second trimming crank swings to drive the thread loosening connecting rod to swing, so that the thread loosening assembly can finish automatic thread loosening action during trimming, and when automatic trimming is performed, the presser foot lifting crank is connected with the base part I of the cam part, so that the presser foot lifting crank cannot swing, and the normal function of the presser foot cannot be influenced during automatic trimming; a needle plate is arranged on the bottom plate, and teeth of the sewing machine are arranged at the needle plate; in an initial state, one end of the tooth adjusting lever is connected with the second convex part on the cam piece, the height of a fed tooth on the needle plate is the highest position, and when automatic thread trimming is performed, the cam piece rotates to enable the position, in which one end of the tooth adjusting lever is in contact with the cam piece, to move from the second convex part to the second base part, so that the height of the tooth on the needle plate is gradually reduced, and the height of the tooth is gradually reduced during automatic thread trimming to enable a thread end after thread trimming to be shorter; the double-output-shaft stepping motor reversely rotates to drive the cam piece to rotate, one end of the tooth adjusting lever is in contact with the base part from the highest point of the second convex part on the cam piece, and finally, the teeth are just sunk below the needle plate from the highest point to complete the downward supply function; the presser foot lifting crank can just finish the motion of the base part I ready to move to the highest point of the convex part I on the cam part, when the highest point of the convex part I of the cam part I is connected with the presser foot lifting crank, the presser foot lifting crank can swing and drive the presser foot lifting crank shaft to rotate so as to enable the presser foot lifting assembly to finish the automatic presser foot lifting action, and at the moment, one end of the tooth adjusting lever is always in contact with the base part I so as to always keep a downward supply state, so that the downward supply function can be finished firstly when the presser foot is lifted automatically, and then the presser foot is lifted, so that a user can place cloth more conveniently; the height of the automatic pressure foot lifting can be controlled by controlling the size of the reversal angle of the double-output-shaft stepping motor; the double-output-shaft stepping motor can perform an automatic thread trimming function and an automatic thread loosening function when rotating forwards, can independently perform a tooth height adjusting function when rotating backwards, and can also perform an automatic presser foot lifting linkage downward supply function; the functions of automatically lifting the presser foot, automatically trimming, automatically loosening the thread, automatically adjusting the tooth height, supplying the thread downwards and the like can be realized through one stepping motor, so that the automation function of the sewing machine is improved, the production cost of the sewing machine is reduced, and the core competitiveness is improved.

Furthermore, in the driving mechanism of the sewing machine, one end of the first thread cutting crank is fixed at the end of the output shaft at one end of the double-output shaft stepping motor, the thread cutting pin shaft is arranged at the side surface of the other end of the first thread cutting crank, one end of the second thread cutting crank is connected with the thread cutting assembly, the chute is arranged at the other end of the second thread cutting crank, the end of the second thread cutting crank is arranged at the notch at one side of the chute and is provided with an extension part extending outwards, one side of the extension part is connected with the chute wall at one side of the chute, the side of the extension part is provided with an arc surface connected with the outer side of the thread cutting roller, and the thread cutting roller can move into the chute from the arc surface. When the trimming roller is contacted with the arc surface of the trimming crank II, the trimming crank I can not drive the trimming crank II to swing to leave an idle stroke for the other end of the double-output-shaft stepping motor to perform functions of lifting a presser foot or adjusting the height of teeth and the like, and only when the trimming roller is positioned in the sliding groove can the trimming crank I drive the trimming crank II to swing so as to realize the action of automatic trimming.

In foretell sewing machine's actuating mechanism, thread trimmer spool is worn to be equipped with by the bottom plate downside, thread trimmer spool's one end with thread trimmer crank two links firmly, thread trimmer spool's the other end has set firmly thread trimmer drive crank, the thread trimmer subassembly is including rotating to be connected the movable cutter seat of bottom plate downside, fix move the sword that moves sword seat one side and fix the bottom plate downside and with move the stationary knife that the sword cooperation is used for the thread trimmer, move the outside of sword seat with be connected with the thread trimmer connecting rod between the thread trimmer drive crank. The second trimming crank swings to drive the trimming shaft to rotate and the trimming driving crank swings, so that the movable cutter holder rotates and drives the movable cutter to approach the fixed cutter, and automatic trimming is achieved.

In the above driving mechanism of the sewing machine, the thread releasing assembly includes a thread pulling plate, a thread pulling wire, a thread releasing plate, a top pin and a thread clamping device, one end side of the thread pulling plate is rotatably connected with a fixed short pin, the end part of the fixed short pin is fixed on the bottom plate, two ends of the thread releasing connecting rod are respectively hinged with the position of the thread cutting crank two close to the thread cutting shaft and one end of the thread pulling plate far away from the fixed short pin, one end of the thread pulling wire is fixed on the thread pulling plate, the other end of the thread pulling wire is connected with the thread releasing plate, the middle part of the thread releasing plate is hinged on a sewing machine shell, the top pin and the thread clamping device are arranged at one end of the thread pulling wire far away from one side of the thread releasing plate, the top pin is arranged between the thread clamping device and the thread releasing plate, one end of the top pin is connected with the thread releasing plate, and a distance is reserved between the other end of the top pin and the thread clamping device, the line loosening plate with the one end side that the knock pin meets has outside butt portion that extends, on the butt portion with one side that the knock pin meets have with the inclined plane of interval grow gradually between the line loosening plate side, the drive of line loosening connecting rod the line loosening plate pendulum kinetic energy makes the knock pin with the thread trapper meets and makes the automatic line that loosens of thread trapper ability. The first thread trimming crank can drive the thread loosening connecting rod to swing, the thread loosening connecting rod and the thread loosening connecting rod are linked, the thread loosening connecting rod drives the thread loosening plate to swing under the action of the thread pulling plate and the thread pulling wire, and due to the arrangement of the inclined plane on the abutting portion, the thread loosening plate can swing to change the distance between the top pin and the thread clamping device, so that the thread loosening purpose is achieved while trimming.

In the driving mechanism of the sewing machine, the cam member includes a presser foot lifting cam and a tooth adjusting cam, the first base portion and the first protrusion portion are both disposed outside the presser foot lifting cam, the second base portion and the second protrusion portion are both disposed outside the tooth adjusting cam, and the first base portion of the presser foot lifting cam and the second base portion of the tooth adjusting cam are both disposed concentrically with the output shaft of the double-output-shaft stepping motor. The tooth height adjusting mechanism is characterized in that a presser foot lifting cam in the cam piece is used for executing an automatic presser foot lifting function, a tooth adjusting cam is used for executing a function of automatically adjusting the height of teeth, the function of independently adjusting the height of the teeth and the function of automatically lifting and feeding the presser foot under linkage are realized through a double-cam combination design, and the tooth height adjusting mechanism is very convenient.

Alternatively, the pressure raising and adjusting cam and the tooth adjusting cam can be integrated. The first base portion and the first projection portion are located on one side of the integral structure, and the second base portion and the second projection portion are located on the other side of the integral structure.

In the driving mechanism of the sewing machine, the presser foot lifting crankshaft is arranged at the lower side of the bottom plate in a penetrating way, the presser foot lifting crank is fixed at one end of the presser foot lifting crankshaft, a presser foot lifting pin shaft is arranged at one side of the end part of the presser foot lifting crank, and a presser foot lifting roller connected with the outer side of the presser foot lifting cam is sleeved on the presser foot lifting pin shaft; and a tooth adjusting pin shaft is arranged on the side surface of one end of the tooth adjusting lever, which is connected with the tooth adjusting cam, and a tooth adjusting roller connected with the outer side of the tooth adjusting cam is sleeved on the tooth adjusting pin shaft. The arrangement of the pressure lifting roller and the tooth adjusting roller improves the stability of the automatic pressure lifting roller and the automatic tooth height adjusting function in execution.

In the driving mechanism of the sewing machine, the presser foot lifting crank shaft is sleeved with a presser foot lifting shaft sleeve, the presser foot lifting shaft sleeve is fixed on the lower side of the bottom plate, the tooth adjusting lever is positioned between the presser foot lifting crank and the presser foot lifting shaft sleeve, two sides of the tooth adjusting lever are respectively connected with the presser foot lifting crank and the presser foot lifting shaft sleeve, and the presser foot lifting crank shaft is fixedly provided with a check ring connected with one end of the presser foot lifting shaft sleeve, which is far away from the tooth adjusting lever. The retainer ring is arranged to prevent the presser foot lifting crank shaft from shifting, so that the reliability of the function of automatically lifting the presser foot and the function of automatically adjusting the height of teeth is improved.

In the driving mechanism of the sewing machine, the presser foot lifting assembly comprises a pressure lever vertically arranged above the needle plate, a presser foot fixedly arranged at the lower end of the pressure lever, a pressure lever guide block fixedly arranged at the upper end of the pressure lever, a presser foot lifting front lever and a presser foot lifting rear lever which are hinged on the sewing machine shell, and a presser foot lifting pull rod positioned between the presser foot lifting front lever and the presser foot lifting rear lever, wherein a lifting plate is hooked on the pressure lever guide block and connected with the presser foot lifting front lever, two ends of the presser foot lifting pull rod are respectively hinged on the presser foot lifting front lever and the presser foot lifting rear lever, a presser foot lifting long ejector rod is further connected on the presser foot lifting rear lever, and a presser foot lifting transmission crank connected with the presser foot lifting long ejector rod is fixedly arranged at one end of the presser foot lifting crank shaft, which is far away from the presser foot lifting crank. The presser foot lifting cam can drive the presser foot lifting crankshaft and the presser foot lifting transmission crank 26 to swing when driving the presser foot lifting crank to swing, and can drive the pressing rod and the presser foot to move up and down under the action of the presser foot lifting long ejector rod, the presser foot lifting rear lever, the presser foot lifting pull rod, the presser foot lifting front lever, the lifting plate and the pressing rod guide block, thereby realizing the function of automatically lifting the presser foot.

In the driving mechanism of the sewing machine, the cloth feeding assembly comprises a feed lifting rock shaft arranged on the lower side of the bottom plate in a penetrating manner, feed teeth arranged on the needle plate in a penetrating manner, a tooth frame fixedly arranged on the lower side of the feed teeth and a feed lifting fork-shaped crank fixedly arranged on the feed lifting rock shaft, one end of the tooth adjusting lever is hinged with a tooth adjusting connecting rod connected with the feed lifting rock shaft, one end of the tooth frame is embedded in a U-shaped end of the feed lifting fork-shaped crank, a connecting shaft is arranged on the lower side of the bottom plate in a penetrating manner, one end of the connecting shaft is fixedly provided with the tooth adjusting crank, the other end of the connecting shaft is fixedly provided with a tooth adjusting swing seat, one side of the tooth adjusting swing seat, which is far away from the connecting shaft, is rotatably connected with a swing pin fixed on the bottom plate, one end of the tooth adjusting connecting rod, which is far away from the tooth adjusting lever, is hinged with the tooth adjusting crank, and one end of the tooth adjusting swing seat is provided with a mounting groove, the tooth lifting mechanism is characterized in that two side groove walls of the mounting groove are hinged to a swinging plate, a connecting pin and a connecting seat sleeved on the connecting pin are further arranged between the two swinging plates, a tooth lifting crank is further fixedly arranged on the tooth lifting shaft, and the tooth lifting crank is hinged to the connecting seat. The swing energy of the tooth adjusting lever drives the tooth adjusting connecting rod to swing, the tooth lifting shaft is driven to swing under the action of the tooth adjusting crank, the connecting shaft, the tooth adjusting swing seat, the swing plate and the connecting seat, the tooth lifting shaft can drive the tooth lifting fork-shaped crank to swing, and then the tooth rack drives the feeding teeth to move up and down front and back, so that the function of automatically adjusting the height of the teeth on the needle plate is realized.

In the driving mechanism of the sewing machine, a spring pin is fixedly arranged in the middle of one side of the tooth adjusting connecting rod, and a tension spring which can enable the tooth adjusting roller to be attached to the tooth adjusting cam is hooked on the spring pin. The tension spring plays a role in stabilizing the connection relationship between the tooth adjusting roller and the tooth adjusting cam.

Compared with the prior art, the utility model has the advantages of it is following:

1. the utility model discloses well two output shaft step motor has just realized lifting the presser foot automatically, automatic trimming, automatic pine line, transferring the tooth height automatically and supplying the function such as down, has reduced sewing machine's manufacturing cost, has improved the core competitiveness of this product on market.

2. The utility model discloses well trimming crank one, trimming crank two, pine line connecting rod and cam piece's structure provides the advantage for realizing carrying presser foot, automatic trimming, automatic pine line, transferring the tooth height automatically and supplying etc. function down.

Drawings

Fig. 1 is a schematic perspective view of a driving mechanism of the sewing machine.

Fig. 2 is a schematic perspective view of the driving mechanism of the sewing machine.

FIG. 3 is a first schematic structural view of a double-output-shaft stepping motor and a thread cutting assembly in the driving mechanism of the sewing machine.

FIG. 4 is a schematic structural view of a double-output-shaft stepping motor and a thread trimming assembly in the driving mechanism of the sewing machine.

FIG. 5 is a schematic view of the structure of a double-output shaft stepping motor, a presser foot lifting assembly and a thread releasing assembly in the driving mechanism of the sewing machine.

FIG. 6 is a first schematic structural view of a double-output-shaft stepping motor, a presser foot lifting assembly and a cloth feeding assembly in the driving mechanism of the sewing machine.

FIG. 7 is a second schematic structural view of a double-output-shaft stepping motor, a presser foot lifting assembly and a cloth feeding assembly in the driving mechanism of the sewing machine.

In the figure, 1, a bottom plate; 2. a needle plate; 3. a thread trimming assembly; 3a, a movable tool apron; 3b, moving the knife; 3c, fixing a cutter; 4. lifting the presser foot assembly; 41. a pressure lever; 42. a presser foot; 43. a compression bar guide block; 44. lifting a presser foot front lever; 45. lifting a rear lever of the presser foot; 46. lifting a presser foot pull rod; 47. a lifting plate; 48. lifting the long ejector pin of the presser foot; 5. a thread releasing assembly; 51. a wire-drawing board; 52. a pull wire; 53. loosening the thread plate; 53a, an abutting portion; 53a1, ramp; 54. a knock pin; 55. a wire clamping device; 56. fixing a short pin; 6. a cloth feeding assembly; 61. a feed lifting shaft; 62. feeding teeth; 63. a dental articulator; 64. a feed lifting fork shaped crank; 65. a connecting shaft; 66. adjusting the swing seat; 66a, a mounting groove; 67. a swing plate; 68. a connecting seat; 69. a feed lifting crank; 7. A double-output-shaft stepping motor; 8. a first trimming crank; 9. a second trimming crank; 91. a chute; 92. An extension; 92a, a circular arc surface; 10. trimming the pin shaft; 11. a thread releasing connecting rod; 12. a cam member; 121. lifting a presser foot cam; 121a, a first base; 121b, a first convex part; 122. a tooth adjusting cam; 122a, base two; 122b, a second projection; 13. a crank shaft for lifting a presser foot; 14. Lifting a presser foot crank; 15. a tooth adjusting lever; 16. a thread trimming roller; 17. a thread cutting shaft; 18. A trimming drive crank; 19. trimming connecting rods; 20. lifting and pressing the pin shaft; 21. lifting and pressing the roller; 22. adjusting a tooth pin shaft; 23. adjusting the tooth roller; 24. lifting the presser foot shaft sleeve; 25. a retainer ring; 26. A presser foot lifting transmission crank; 27. a tooth adjusting connecting rod; 28. a swing pin; 29. adjusting a tooth crank; 30. a connecting pin; 31. a spring pin; 32. a tension spring.

Detailed Description

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

As shown in fig. 1 to 4, the sewing machine in this embodiment includes a bottom plate 1, a needle plate 2 is disposed on the bottom plate 1, the sewing machine further includes a thread cutting assembly 3, a presser foot lifting assembly 4, a thread loosening assembly 5 and a cloth feeding assembly 6, the driving mechanism includes a double-output shaft stepping motor 7, two ends of the double-output shaft stepping motor 7 are respectively provided with a bracket, upper ends of the two brackets are respectively fixed on a lower side of the bottom plate 1, an output shaft at one end of the double-output shaft stepping motor 7 is fixedly provided with a thread cutting crank 8, and the other end is fixedly provided with a cam member 12, a thread cutting shaft 17 is penetrated through a lower side of the bottom plate 1, the thread cutting shaft 17 is sleeved with a thread cutting shaft sleeve, the thread cutting shaft sleeve is fixed on the bottom plate 1, two ends of the thread cutting shaft 17 are respectively fixedly provided with a thread cutting crank two 9 and a thread cutting driving crank 18, the thread cutting assembly 3 includes a movable knife 3b and a fixed knife 3c which are matched with each other for cutting thread, a lower side of the bottom plate 1 is rotatably connected with a movable knife holder 3a, the movable knife 3b is fixed on one side of the movable knife seat 3a, the outer side of the movable knife seat 3a is connected with the end part of the trimming drive crank 18 through the trimming connecting rod 19, the fixed knife 3c is fixed on the lower side of the bottom plate 1 and extends to the lower part of the needle plate 2 for trimming wires in cooperation with the movable knife 3b, one end of the trimming crank 8 is fixed on one end of the double-output-shaft stepping motor 7, the trimming pin shaft 10 is arranged on the other end side of the trimming crank 8, the trimming roller 16 is sleeved on the trimming pin shaft 10, one end of the trimming crank 9 is fixed on the trimming shaft 17, the sliding groove 91 extending inwards is formed in the middle of the other end of the trimming crank 9, the end of the trimming crank 9 is positioned on one side of the notch of the sliding groove 91 and is provided with an extension part 92 extending outwards, one side of the extension part 92 is connected with the groove wall on one side of the sliding groove 91 and is provided with an arc surface 92a, the outer peripheral surface of the trimming roller 16 is connected with the arc surface 92a of the extension part 92a, and can move into the sliding groove 91 from the arc surface 92a, when the trimming roller 16 is connected with the arc surface 92a of the extension portion 92, the trimming crank 8 cannot drive the trimming shaft 17 to swing, when the trimming roller 16 is located in the sliding groove 91, the trimming crank 8 swings to drive the trimming shaft 17 to rotate, the trimming shaft 17 rotates to drive the trimming drive crank 18 to swing so as to drive the movable tool holder 3a to rotate, so that the movable tool 3b approaches the fixed tool 3c, and the trimming shaft 17 is sleeved with a reset torsion spring.

Further, as shown in fig. 5, a thread releasing connecting rod 11 is hinged on the second thread cutting crank 9, one end of the thread releasing connecting rod 11 is connected with the second thread cutting crank 9, the thread releasing assembly 5 comprises a thread pulling plate 51, one end of the thread pulling plate 51 is hinged with the other end of the thread releasing connecting rod 11, a thread pulling 52 is fixed on the thread pulling plate 51, one end of the thread pulling 52, which is far away from the thread pulling plate 51, is connected with a thread releasing plate 53, the middle part of the thread releasing plate 53 is hinged on a machine shell of the sewing machine, one side of the thread releasing plate 53 is provided with a top pin 54 and a thread clamp 55, the thread pulling 52 is connected with one end of the thread releasing plate 53, the top pin 54 and the thread clamp 55 are positioned at the other end of the thread releasing plate 53, one side of the end of the thread releasing plate 53 is provided with an outward extending abutting part 53a, one end of the top pin 54 is connected with the abutting part 53a, one side of the abutting part 53a is provided with an inclined surface 53a1, the distance between the inclined surface 53a1 and the side of the thread releasing plate 53 is gradually reduced, the other end of the top pin 54 is spaced from the wire clamping device 55, the side face, far away from the wire releasing connecting rod 11, of one end of the wire pulling plate 51 is rotatably connected with a fixed short pin 56, the end portion of the fixed short pin 56 is fixed on the bottom plate 1, and the wire releasing connecting rod 11 can swing to drive the wire releasing plate 53 to swing so that the top pin 54 is in contact with the wire clamping device 55 to enable the wire clamping device 55 to automatically release wires.

Further, as shown in fig. 3 to 7, the cam member 12 includes a pressure raising and pressing pin cam 121 and a tooth adjusting cam 122, the pressure raising and pressing pin cam 121 and the tooth adjusting cam 122 are integrally formed or are two separate parts, a base portion 121a and a convex portion 121b are provided outside the pressure raising and pressing pin cam 121, a base portion two 122a and a convex portion two 122b are provided outside the tooth adjusting cam 122, the base portion one 121a of the pressure raising and pressing pin cam 121 and the base portion two 122a of the tooth adjusting cam 122 are both concentrically arranged with an output shaft of the double-output shaft stepping motor 7, a pressure raising and pressing pin crankshaft 13 is provided through the lower side of the base plate 1, a pressure raising and pressing pin shaft sleeve 24 is sleeved on the pressure raising and pressing pin crankshaft 13, the pressure raising and pressing pin shaft sleeve 24 is fixed on the base plate 1, a pressure raising and pressing pin crank 14 is fixed at one end of the pressure raising and pressing pin crank 13, a pressing pin shaft 20 is provided on the pressure raising and pressing pin shaft 20, a pressure raising and pressing roller 21 connected with the outer side of the pressure raising and pressing pin cam 121 is sleeved on the outer side of the pressure raising and pressing pin shaft, the tooth adjusting lever 15 is sleeved on the lifting and pressing foot crank shaft 13, a tooth adjusting pin shaft 22 is arranged on one end side of the tooth adjusting lever 15, a tooth adjusting roller 23 connected with the outer side of the tooth adjusting cam 122 is sleeved on the tooth adjusting pin shaft 22, a lifting and pressing foot transmission crank 26 is fixedly arranged at the other end of the lifting and pressing foot crank shaft 13, one side of the tooth adjusting lever 15 is connected with the lifting and pressing foot crank 14, the other side of the tooth adjusting lever is connected with one end of a lifting and pressing foot shaft sleeve 24, and a retaining ring 25 located at the other end of the lifting and pressing foot shaft sleeve 24 is fixedly arranged on the lifting and pressing foot crank shaft 13.

Further, as shown in fig. 1, 2 and 5 to 7, the presser foot lifting assembly 4 includes a pressing rod 41, a presser foot 42, a pressing rod guide block 43, a presser foot lifting front lever 44, a presser foot lifting rear lever 45 and a presser foot lifting pull rod 46, the pressing rod 41 is vertically arranged above the needle plate 2, the presser foot 42 is arranged at the lower end of the pressing rod 41, the pressing rod guide block 43 is fixed at the upper end of the pressing rod 41, a lifting plate 47 is hooked on the pressing rod guide block 43, one end of the lifting plate 47 is connected with the front end of the presser foot lifting front lever 44, the middle parts of the presser foot lifting front lever 44 and the presser foot lifting rear lever 45 are both hinged on the sewing machine shell, two ends of the presser foot lifting pull rod 46 are respectively hinged with the rear end of the presser foot lifting front lever 44 and the front end of the presser foot lifting rear lever 45, the rear end of the presser foot lifting rear lever 45 is hinged with a presser foot long ejector rod 48, one end of the presser foot lifting long ejector rod 48 far away from the presser foot lifting rear lever 45 is hinged with the end of the presser foot lifting transmission crank 26, one end of the tooth adjusting lever 15 is hinged with a tooth adjusting connecting rod 27, one end of the tooth adjusting connecting rod 27 far away from the tooth adjusting lever 15 is hinged with a tooth adjusting crank 29, the lower side of the bottom plate 1 is provided with a connecting shaft 65 in a penetrating way, the tooth adjusting crank 29 is fixed at one end of the connecting shaft 65, the other end of the connecting shaft 65 is fixed with a tooth adjusting swing seat 66, one side of the tooth adjusting swing seat 66 far away from the connecting shaft 65 is rotatably connected with a swing pin 28, the end part of the swing pin 28 is fixed at the lower side of the bottom plate 1, the cloth feeding component 6 comprises a tooth lifting shaft 61, a feeding tooth 62, a tooth rack 63 and a feeding shaft, the tooth lifting shaft 61 is fixedly provided with a tooth lifting fork-shaped crank 64, one end of the tooth rack 63 is embedded at a U-shaped end of the tooth lifting fork-shaped crank 64, the other end of the tooth is hinged with the feeding shaft, the feeding tooth 62 is arranged on the needle plate 2 in a penetrating way, the upper side of the tooth rack 63 is fixedly connected with the lower side of the feeding tooth 62, a tooth lifting crank 69 is fixedly provided with a tooth adjusting swing seat 66a, the groove walls on the two sides of the mounting groove 66a are respectively hinged with a swinging plate 67, a connecting pin 30 is arranged between the two swinging plates 67, a connecting seat 68 is sleeved on the connecting pin 30, and one end, far away from the connecting pin 30, of the connecting seat 68 is hinged with the end part of a feed lifting crank 69; the middle part of one side of the tooth adjusting connecting rod 27 is provided with a spring pin 31, a tension spring 32 is hooked on the spring pin 31, and the tooth adjusting roller 23 is always attached to the tooth adjusting cam 122 due to the arrangement of the tension spring 32.

When the automatic thread trimming is carried out, the double-output-shaft stepping motor 7 rotates forwards to drive the first thread trimming crank 8 to rotate so as to drive the second thread trimming crank 9 and the thread trimming shaft 17 to rotate together, so that the thread trimming drive crank 18, the thread trimming connecting rod 19 and the movable cutter seat 3a are linked, finally, the movable cutter 3b and the fixed cutter 3c are meshed with each other to finish the thread trimming action, and the resetting is finished under the combined action of the torsion spring and the double-output-shaft stepping motor 7; the second trimming crank 9 can drive the thread releasing connecting rod 11 to swing while swinging so as to drive the thread pulling plate 51 to rotate, the thread pulling 52 can drive the thread releasing plate 53 to rotate so as to drive the ejector pin 54 to move forwards to jack the thread clamping device 55 to complete automatic thread releasing during trimming, and the two are in linkage design; during automatic trimming, the presser foot lifting cam 121 just executes an idle stroke on the first base part 121a, so that the normal function of the presser foot lifting cannot be influenced during automatic trimming; the tooth adjusting cam 122 is designed as a centrosymmetric cam, the tooth adjusting roller 23 is connected with the highest point position of the second convex part 122b on the tooth adjusting cam 122 in the initial state, at the moment, the upper end of the tooth is positioned just above the needle plate 2 and is positioned at the highest point, and when the automatic trimming action is executed, the position where the tooth adjusting cam 122 is connected with the tooth adjusting roller 23 just goes from the highest point of the second convex part 122b to the position of the second base part 122a, so that the height of the tooth can move downwards from the highest point, and the height of the tooth can gradually become lower during the automatic trimming so that the trimmed thread end is shorter.

When the height of teeth is automatically adjusted, the double-output-shaft stepping motor 7 reversely rotates to drive the tooth adjusting cam 122 and the presser foot lifting cam 121 to rotate together within a fixed angle, the tooth adjusting roller 23 drives the tooth adjusting lever 15 to rotate together with a four-link structure consisting of the tooth adjusting connecting rod 27 and the tooth adjusting crank 29, finally the connecting shaft 65 drives the tooth adjusting swing seat 66 to rotate within a certain range, and the spatial angle value of the tooth adjusting swing seat 66 determines the height value of the teeth on the needle plate 2; the lifting and pressing roller 21 just can execute an idle stroke on the base part first 121a of the lifting and pressing foot cam 121, and the trimming roller 16 also executes an idle stroke on the arc surface 92a on the trimming crank second 9, so that trimming and automatic lifting and pressing foot functions cannot be influenced when the tooth height is automatically adjusted.

When the presser foot is automatically lifted, the double-output-shaft stepping motor 7 reversely rotates to drive the tooth adjusting cam 122 and the presser foot lifting cam 121 to rotate together, so that the tooth adjusting cam 122 drives the tooth adjusting roller 23 to move from the highest point of the second convex part 122b to the second base part 122a to enable the tooth adjusting swing seat 66 to complete angle change, and finally, the teeth just sink below the needle plate 2 from the highest point to complete the lower supply function; at this time, the lifting and pressing roller 21 can just walk on the lifting and pressing foot cam 121 to finish the movement of the first base part 121a to the highest point of the first convex part 121b, when the lifting and pressing foot cam 121 drives the lifting and pressing roller 21 to be in contact with the highest point of the first convex part 121b, the lifting and pressing foot crank shaft 13 is rotated to drive the four-bar mechanism consisting of the lifting and pressing foot long ejector rod 48, the lifting and pressing foot rear bar 45, the lifting and pressing foot pull rod 46 and the lifting and pressing foot front lever 44 to rotate so that the pressing rod 41 drives the pressing foot 42 to be lifted to the highest point to finish the automatic lifting and pressing foot function, at this time, the tooth adjusting roller 23 always rolls on the second base part 122a of the tooth adjusting cam 122 to always keep a downward supply state, therefore, the downward supply function can be finished before the lifting and then the pressing foot 42 can be lifted during the automatic lifting and the height of the automatic lifting and pressing foot can be controlled by controlling the reverse angle of the double-shaft stepping motor 7.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Claims

1. A driving mechanism of a sewing machine comprises a bottom plate (1), a thread cutting assembly (3), a presser foot lifting assembly (4), a thread loosening assembly (5) and a cloth feeding assembly (6), and is characterized by comprising a double-output-shaft stepping motor (7) fixed on the lower side of the bottom plate (1), wherein a crank assembly capable of enabling the thread cutting assembly (3) to perform automatic thread cutting action and enabling the thread loosening assembly (5) to perform thread loosening action is arranged on an output shaft at one end of the double-output-shaft stepping motor (7); a cam component which can enable the pressure foot lifting component (4) to carry out pressure foot lifting action and can drive the cloth feeding component (6) to adjust tooth height is arranged on an output shaft at the other end of the double-output-shaft stepping motor (7).

2. The drive mechanism of the sewing machine according to claim 1, characterized in that the crank assembly comprises a first thread cutting crank (8) fixedly arranged on an output shaft at one end of the double-output-shaft stepping motor (7); the trimming mechanism is characterized in that the trimming component (3) is connected with a trimming crank II (9), a trimming pin shaft (10) is arranged on one side of the trimming crank I (8), a trimming roller (16) is sleeved on the trimming pin shaft (10), a sliding groove (91) for the trimming roller (16) to be slidably embedded into is formed in the trimming crank II (9), and one end of the trimming crank II (9) is connected with the trimming component (3); the second thread trimming crank (9) is further hinged with a thread releasing connecting rod (11), and the thread releasing connecting rod (11) is connected with the thread releasing assembly (5).

3. The driving mechanism of the sewing machine according to claim 2, characterized in that a thread cutting shaft (17) penetrates through the lower side of the bottom plate (1), one end of the thread cutting shaft (17) is fixedly connected with the second thread cutting crank (9), the other end of the thread cutting shaft (17) is fixedly provided with a thread cutting driving crank (18), the thread cutting component (3) comprises a movable cutter holder (3a) rotatably connected to the lower side of the bottom plate (1), a movable cutter (3b) fixed on one side of the movable cutter holder (3a) and a fixed cutter (3c) fixed on the lower side of the bottom plate (1) and matched with the movable cutter (3b) for thread cutting, and a thread cutting connecting rod (19) is connected between the outer side of the movable cutter holder (3a) and the thread cutting driving crank (18).

4. The drive mechanism of the sewing machine according to claim 3, characterized in that the thread releasing assembly (5) comprises a thread pulling plate (51), a thread pulling wire (52), a thread releasing plate (53), a top pin (54) and a thread clamping device (55), a fixed short pin (56) is rotatably connected to one end side of the thread pulling plate (51), the end part of the fixed short pin (56) is fixed on the base plate (1), two ends of a thread releasing connecting rod (11) are respectively hinged with the position of the thread cutting crank II (9) close to the thread cutting shaft (17) and one end of the thread pulling plate (51) far away from the fixed short pin (56), one end of the thread pulling wire (52) is fixed on the thread pulling plate (51), the other end of the thread pulling wire (52) is connected with the thread releasing plate (53), the middle part of the thread releasing plate (53) is hinged on the sewing machine shell, the top pin (54) and the thread clamping device (55) are arranged on the side of the thread releasing plate (53) far away from the thread pulling wire (52) The thread loosening connecting rod (11) drives the thread loosening plate (53) to swing to enable the ejector pin (54) to be connected with the thread clamping device (55) to enable the thread clamping device (55) to automatically loosen threads, the ejector pin (54) is located between the thread clamping device (55) and one end of the thread loosening plate (53) is connected with the thread loosening plate (53), the other end of the ejector pin (54) is spaced from the thread clamping device (55), the side face of one end, connected with the ejector pin (54), of the thread loosening plate (53) is provided with an abutting portion (53a) extending outwards, an inclined face (53a1) with the spacing gradually increased from the side face of the thread loosening plate (53) is arranged on one side, connected with the ejector pin (54), of the thread loosening connecting rod (11).

5. The driving mechanism of sewing machine according to claim 1 or 2 or 3 or 4, characterized in that the cam assembly comprises a cam member (12) fixed on the output shaft at the other end of the double output shaft stepping motor (7); the pressure foot lifting and lifting assembly (4) is connected with a pressure foot lifting and lifting crank shaft (13), a pressure foot lifting crank (14) is fixedly arranged at one end, far away from the pressure foot lifting and lifting assembly (4), of the pressure foot lifting and lifting crank shaft (13), a base part I (121a) and a convex part I (121b) which can be connected with the pressure foot lifting and lifting crank (14) are arranged on the outer side of the cam piece (12), and the convex part I (121b) can drive the pressure foot lifting and lifting crank (14) to swing; the presser foot lifting crank shaft (13) is sleeved with a tooth adjusting lever (15), one end of the tooth adjusting lever (15) is connected with the cloth feeding assembly (6), and the outer side of the cam piece (12) is provided with a second base part (122a) and a second convex part (122b) which are connected with the other end of the tooth adjusting lever (15).

6. The drive mechanism of a sewing machine according to claim 5, characterized in that the cam member (12) includes a presser foot lifting cam (121) and a tooth adjusting cam (122), the first base portion (121a) and the first protrusion portion (121b) are both disposed outside the presser foot lifting cam (121), the second base portion (122a) and the second protrusion portion (122b) are both disposed outside the tooth adjusting cam (122), and the first base portion (121a) of the presser foot lifting cam (121) and the second base portion (122a) of the tooth adjusting cam (122) are both disposed concentrically with the output shaft of the double output shaft stepping motor (7).

7. The driving mechanism of the sewing machine according to claim 6, characterized in that the presser foot lifting crank shaft (13) is arranged at the lower side of the bottom plate (1) in a penetrating way, the presser foot lifting crank (14) is fixed at one end of the presser foot lifting crank shaft (13), a presser foot lifting pin shaft (20) is arranged at one side of the end part of the presser foot lifting crank (14), and a presser foot lifting roller (21) connected with the outer side of the presser foot lifting cam (121) is sleeved on the presser foot lifting pin shaft (20); the tooth adjusting device is characterized in that a tooth adjusting pin shaft (22) is arranged on the side face of one end, connected with the tooth adjusting cam (122), of the tooth adjusting lever (15), and a tooth adjusting roller (23) connected with the outer side of the tooth adjusting cam (122) is sleeved on the tooth adjusting pin shaft (22).

8. The driving mechanism of the sewing machine according to claim 7, characterized in that a presser foot lifting shaft sleeve (24) is sleeved on the presser foot lifting crankshaft (13), the presser foot lifting shaft sleeve (24) is fixed on the lower side of the bottom plate (1), the tooth adjusting lever (15) is positioned between the presser foot lifting crank (14) and the presser foot lifting shaft sleeve (24) and two sides of the tooth adjusting lever are respectively connected with the presser foot lifting crank (14) and the presser foot lifting shaft sleeve (24), and a retainer ring (25) connected with one end of the presser foot lifting shaft sleeve (24) far away from the tooth adjusting lever (15) is fixedly arranged on the presser foot lifting crankshaft (13).

9. The driving mechanism of sewing machine according to claim 8, characterized in that the bottom plate (1) is provided with a needle plate (2), the presser foot lifting assembly (4) comprises a pressing rod (41) vertically arranged above the needle plate (2), a presser foot (42) fixedly arranged at the lower end of the pressing rod (41), a pressing rod guide block (43) fixedly arranged at the upper end of the pressing rod (41), a presser foot lifting front lever (44) and a presser foot lifting rear lever (45) hinged on the sewing machine shell, and a presser foot lifting pull rod (46) positioned between the presser foot lifting front lever (44) and the presser foot lifting rear lever (45), the pressing rod guide block (43) is hooked with a lifting plate (47), the lifting plate (47) is connected with the presser foot lifting front lever (44), two ends of the presser foot lifting pull rod (46) are respectively hinged on the presser foot lifting front lever (44) and the presser foot lifting rear lever (45), the presser foot lifting rear lever (45) is also connected with a presser foot lifting long ejector rod (48), and one end of the presser foot lifting crankshaft (13) far away from the presser foot lifting crank (14) is fixedly provided with a presser foot lifting transmission crank (26) connected with the presser foot lifting long ejector rod (48).

10. The driving mechanism of sewing machine according to claim 8, characterized in that the bottom plate (1) is provided with a needle plate (2), the cloth feeding assembly (6) comprises a feed lifting shaft (61) arranged at the lower side of the bottom plate (1) in a penetrating manner, a feed dog (62) arranged on the needle plate (2) in a penetrating manner, a tooth frame (63) fixedly arranged at the lower side of the feed dog (62) and a feed lifting fork-shaped crank (64) fixedly arranged on the feed lifting shaft (61), one end of the tooth adjusting lever (15) is hinged with a tooth adjusting connecting rod (27) connected with the feed lifting shaft (61), one end of the tooth frame (63) is embedded in the U-shaped end of the feed lifting fork-shaped crank (64), a connecting shaft (65) is arranged at the lower side of the bottom plate (1), one end of the connecting shaft (65) is fixedly provided with a tooth adjusting crank (29), and the other end of the connecting shaft (65) is fixedly provided with a tooth adjusting swing seat (66), one side, far away from the connecting shaft (65), of the tooth adjusting swing seat (66) is rotatably connected with a swing pin (28) fixed on the bottom plate (1), one end, far away from the tooth adjusting lever (15), of the tooth adjusting connecting rod (27) is hinged to the tooth adjusting crank (29), one end of the tooth adjusting swing seat (66) is provided with a mounting groove (66a), two side groove walls of the mounting groove (66a) are hinged to swing plates (67), a connecting pin (30) and a connecting seat (68) sleeved on the connecting pin (30) are further arranged between the two swing plates (67), a tooth lifting crank (69) is further fixedly arranged on the tooth lifting shaft (61), and the tooth lifting crank (69) is hinged to the connecting seat (68).