CN218893822U

CN218893822U - Sewing machine

Info

Publication number: CN218893822U
Application number: CN202222585029.3U
Authority: CN
Inventors: 阮孟定
Original assignee: Zhejiang Duma Sewing Machine Co ltd
Current assignee: Zhejiang Duma Sewing Machine Co ltd
Priority date: 2021-09-28
Filing date: 2022-09-28
Publication date: 2023-04-21
Anticipated expiration: 2032-09-28
Also published as: CN116446116A

Abstract

The utility model belongs to the technical field of sewing, and particularly relates to a sewing machine, which comprises a frame, and a stitch length adjusting mechanism, a thread trimming mechanism and a presser foot lifting mechanism which are arranged on the frame, wherein a motor is arranged at the lower part of the frame, a first output shaft of the motor is used for driving a swinging seat of the stitch length adjusting mechanism, one side of the swinging seat is provided with a first supporting shaft, and one end of the first supporting shaft drives the swinging seat to swing within a set angle; the other end of the first supporting shaft extends towards the position of the motor and is provided with a first stirring piece, and a first chute is formed in the first stirring piece; the first output shaft is provided with a first crank, the first crank is provided with a sliding block, and the sliding block slides in the first sliding groove, so that the whole structure is compact; in addition, the lower region of the frame can be better utilized.

Description

Sewing machine

Technical Field

The utility model relates to the technical field of sewing, in particular to a sewing machine.

Background

The existing sewing machine is a machine for sewing the sewing material by a stitch. The sewing machine comprises a needle bar mechanism, a thread picking mechanism, a feeding mechanism, a thread hooking mechanism, a pressing mechanism, a presser foot lifting mechanism, a stitch length adjusting mechanism, a thread shearing mechanism and the like, and along with the development of automation, the mechanisms are gradually improved and provided with driving parts, wherein the driving parts comprise a motor, an electromagnet, an air cylinder, an oil cylinder and the like. The sewing machine realizes backstitch when the stitch length is regulated to a negative value by the stitch length regulating mechanism.

In the prior art, the motor drives the stitch length adjusting mechanism to realize the adjustment of the stitch length adjusting mechanism through cam rotation, such as a driving device for trimming, lifting a presser foot and adjusting the stitch length of Chinese patent application No. 202011225730.3, the stitch length adjusting cam is a curved edge quadrangle, the stitch length adjusting mechanism is abutted against the peripheral wall of the stitch length adjusting cam, and the stitch length adjusting roller on the swinging ejector rod is abutted against and contacted with different surfaces of the curved edge quadrangle, so that the stitch length of the sewing machine is adjusted under different movements.

A motor drives the thread cutting mechanism, the presser foot lifting mechanism and the stitch length adjusting mechanism simultaneously, and the essence of the thread cutting mechanism is that the motor shaft rotating angle is divided, and three angles corresponding to the thread cutting mechanism, the presser foot lifting mechanism and the stitch length adjusting mechanism are reasonably divided in a 360-degree rotating range. Under the general condition of a motor shaft, the motor shaft is positioned in a needle pitch adjusting area, enters a corresponding thread trimming area or a corresponding presser foot lifting area when thread trimming or presser foot lifting is needed, and returns to the needle pitch adjusting area after execution is finished;

the utility model has the advantages of the prior art that when the curved edge quadrangle rotates, the curved edge quadrangle is easy to collide with the needle pitch adjusting roller to cause damage, and the movement between the curved edge quadrangle and the needle pitch adjusting roller is relatively unstable, the whole structure is relatively complex and not compact enough.

Disclosure of Invention

The utility model aims to provide a sewing machine which has more centralized transmission and lower cost and realizes two or three actions through one motor.

The purpose of the utility model is realized in the following way:

a sewing machine comprises a frame, a thread cutting mechanism, a presser foot lifting mechanism and a stitch length adjusting mechanism, wherein a driving motor is arranged at the lower part of the frame,

the second output shaft of the driving motor extends forwards and drives the wire cutting mechanism,

a first output shaft of the driving motor extends backwards and drives the presser foot lifting mechanism and the stitch length adjusting mechanism,

a first crank is arranged on the first output shaft and drives the needle pitch adjusting mechanism;

a first support shaft is arranged on one side of the swing seat of the needle pitch adjusting mechanism, and drives the swing seat to swing within a set angle; the orientation of first back shaft driving motor's one end is provided with first piece of stirring, has seted up first spout on the first piece of stirring, is provided with the slider in the first spout, first cranked outer end is provided with the slider.

Preferably, a first cam is arranged on the first output shaft, and drives the presser foot lifting mechanism;

the double swing rod is rotatably arranged on the rack and is provided with a first swing arm and a second swing arm; the swing arm end of the first swing arm is hinged with a pressure foot lifting connecting rod, and the swing arm end of the second swing arm is propped against the first cam.

Preferably, the duplex swing rod is arranged below the first stirring piece, and the first stirring piece is positioned between the first swing arm and the second swing arm of the duplex swing rod.

Preferably, a roller is hinged at the swing arm end of the second swing arm of the duplex swing rod, and the roller abuts against the wheel surface of the first cam.

Preferably, a second support shaft is arranged on the other side of the swing seat; the first support shaft and the second support shaft are arranged on the same axis and extend into two side parts of the swing seat respectively;

the first support shaft is also provided with a second stirring piece, and the second stirring piece is provided with a second chute;

the side part of the swing seat, which is close to the first supporting shaft, is provided with a poking pin, and the poking pin is arranged in the second sliding groove.

Preferably, the second output shaft is provided with a second crank, and a second cam is arranged on the second crank and drives the wire cutting mechanism;

and a through hole is formed in the second cam, one end of the second crank is arranged in the through hole, and the working curved surface of the second cam is the inner wall of the through hole.

Preferably, the first cam comprises a rotating end and a protruding end, the rotating end is connected with the first output shaft, and the protruding end is used for poking the second swing arm;

the first cam is provided with a working curved surface and a non-working curved surface, wherein the working curved surface is the peripheral surface of the protruding end, and the non-working curved surface is the peripheral surface of the rotating end.

Preferably, the driving motor is transversely arranged at the lower side of the middle part of the frame.

Preferably, a rotating shaft is arranged on the duplex swing rod in a penetrating way, and the duplex swing rod rotates around the rotating shaft;

the rotating shaft is provided with a reset spring for resetting the presser foot, one end of the reset spring is arranged on the frame, and the other end of the reset spring is arranged on the duplex swing rod.

Preferably, the front end of the frame is provided with a trimming mechanism, and the trimming mechanism comprises

A bearing seat arranged on the sewing machine body;

the trimming motor is arranged on the bearing seat and is used for providing power;

the cutter assembly is arranged on the bearing seat and can vertically lift;

the crank connecting rod assembly is arranged in the bearing seat, one end of the crank connecting rod assembly is a power input end, and the other end of the crank connecting rod assembly is a power output end; the power input end is connected with a motor shaft of the trimming motor, and the power output end is connected with the cutter assembly;

the tool rest guide frame is arranged in the bearing seat and is provided with a vertical chute; the power output end is provided with a guide sliding block, the guide sliding block is positioned in the sliding groove, and the guide sliding block is connected with the guide post of the cutter assembly; the crank connecting rod assembly converts rotation of a motor shaft of the trimming motor into vertical lifting of the cutter assembly.

Preferably, the crank connecting rod assembly comprises a crank shaft sleeve connecting rod and a guide post; the motor shaft is provided with the crank shaft sleeve in a penetrating mode, the swinging end of the crank shaft sleeve is hinged to the upper end of the connecting rod, the lower end of the connecting rod is sleeved on the guide post, one end of the guide post is fixedly connected with the upper end of the cutter component, and the other end of the guide post is connected with the guide sliding block.

Preferably, the cutter assembly is provided with a cutter bar and a cutter rest; the tool rest comprises a fixed bracket and an adjusting bracket; the fixed support is arranged at the lower end of the cutter bar, a groove matched with the fixed support is formed at the top end of the adjusting support, and the adjusting support is assembled on the fixed support through the groove;

the surface of the adjusting bracket is provided with an adjusting groove, and a bolt penetrates through the adjusting groove to screw the fixing bracket and the adjusting bracket into a whole;

the lower part of the adjusting bracket is provided with a cutter.

Preferably, the lower part of the frame is further provided with a knee rest assembly comprising: the sensor is used for acquiring a trigger signal; the sensed piece is used for triggering the sensor; the knee rest executing component is used for driving the sensed piece to move along a set track; a knee rest driving part for driving the knee rest executing part; a connecting frame for being fixed on the adapted sewing machine and directly or indirectly carrying the rest of the components; the knee rest executing component comprises a rotating rod and a mounting sleeve; the rotating lever includes: the device comprises a rotating part, a swinging part and a limiting part; the rotating part, the swinging part and the limiting part are integrally formed; the rotating part is rotatably arranged on the connecting frame; one end of the rotating part extends out of the connecting frame and is connected with the knee rest driving part; a swinging part which is arranged at the other end of the rotating part and bends towards one side; the limiting part is arranged at the swinging end of the swinging part and bends towards the other side; the end part of the limiting part extends into the waist-shaped hole of the connecting frame; the swinging part or the limiting part is provided with the mounting sleeve, and the mounting sleeve is provided with the sensed piece.

According to one embodiment of the utility model, the mounting sleeve is provided with a mounting groove fixing part, a fixing cap part and a side leaning part; the mounting sleeve is arranged at the corner where the swinging part is connected with the limiting part; the fixed cap part is sleeved on the limit part; a side leaning part leaning on the swinging part; the side leaning part is provided with a fixing hole and is fixed on the swinging part through a screw penetrating through the fixing hole; the mounting sleeve is a plastic piece.

Compared with the prior art, the utility model has the following outstanding and beneficial technical effects:

1. according to the utility model, the driving motor drives the first stirring piece to rotate through the first crank through the design of the sliding groove and the sliding block, so that when the gauge needle distance adjusting assembly is driven, the inner wall of the first sliding groove can always limit the movement of the sliding block, so that the sliding block can only reciprocate linearly along the extending direction of the first sliding groove, the first crank can further stabilize when driving the first stirring piece to rotate, the first stirring piece can also stabilize when driving the gauge needle distance adjusting assembly to move, the error rate of the gauge needle distance adjusting assembly is reduced, and the yield of products is improved; in the process of 360 DEG rotation of the first crank, the sliding block always slides in the first sliding groove, so that the trimming area and the presser foot lifting area can be sequentially arranged when the working angle of the motor shaft of the driving motor is divided; when only the presser foot is lifted and the thread is not cut, the motor shaft enters from the presser foot lifting area and does not enter the thread cutting area; when the thread is needed to be cut and the presser foot is lifted, the motor shaft rotates in the opposite direction, enters from the thread cutting area and enters into the presser foot lifting area, the motor shaft can rotate 360 degrees and then returns to the set stitch length position, repeated positive and negative rotation is not needed, the response of the motor is facilitated, and the service life is prolonged.

2. The first supporting shaft and the first output shaft are arranged up and down in a vertical plane and are arranged front and back in a horizontal plane; the first toggle piece is downwards arranged, so that a working area of the first toggle piece forms a sector area which swings at a certain angle; the working area of the first crank is a circular area in the sector area, so that the whole structure is compact; in addition, the lower region of the frame can be better utilized.

3. The double-link swing rod is arranged below the first toggle piece, and the first toggle piece is positioned between the first swing arm and the second swing arm of the double-link swing rod. The fan-shaped area formed by the deflection of the first toggle piece by a certain angle is not interfered with the duplex swing rod, a plurality of parts are compact, the installation space is contracted to a smaller range, and the whole installation space is further saved; meanwhile, the structure of the existing presser foot lifting connecting rod and the like can be applied, and large-scale adjustment is not needed.

4. After the double-linked swing rod is driven by the protruding end of the first cam to incline for a certain angle, the presser foot can be lifted or lowered, and the reset spring can be tensioned. When the non-working surface of the duplex swing rod, namely the rotating end is contacted with the roller, the reset spring drives the self-reset, and simultaneously drives the duplex swing rod to reset, finally, the reset of the presser foot is realized, and the reset structure is simple and effective.

5. The trimming mechanism is provided with the independent trimming motor, motor driving of the sewing machine is not needed any more, and the trimming mechanism can still execute trimming action when the angle of cloth is rotated.

6. The knee rest component is provided with the rotating rod and the mounting sleeve, the sensed piece is arranged on the mounting sleeve, and the rotating rod is integrally formed, so that signal interference to the sensor is avoided, the structure of the rotating rod is simplified, the strength of the rotating rod is improved, the loosening condition is avoided, and the service life of the component is prolonged; further, because the structure is simplified, the installation difficulty of the assembly is reduced, the installation precision is improved, and the processing cost is reduced.

Drawings

Fig. 1 is a schematic view of the whole structure of a sewing machine.

Fig. 2 is a schematic structural view of a thread cutting, presser foot lifting and stitch length adjusting mechanism.

Fig. 3 is a schematic view of a part of the structure of the presser foot lifting and needle pitch adjusting mechanism.

Fig. 4 is a schematic diagram of a connection structure between the second cam and the second crank.

Fig. 5 is a schematic view illustrating the rotation angle division of the driving motor.

Fig. 6 is a schematic view of the structure of the knee rest assembly.

Fig. 7 is a schematic view of an exploded view of the knee bolster assembly.

Fig. 8 is a schematic view of the structure of the knee rest assembly.

Fig. 9 is a schematic view of the structure of the knee rest assembly.

Figure 10 is a schematic cross-sectional view of a knee bolster assembly.

FIG. 11 is a schematic view of the mounting sleeve of the knee bolster assembly.

FIG. 12 is a schematic view of the mounting sleeve of the knee bolster assembly.

Fig. 13 is one of the structural views of the trimming mechanism.

FIG. 14 is a second block diagram of the trimming mechanism.

Fig. 15 is an exploded view of the trimming mechanism.

Fig. 16 is a structural view of the trimming mechanism after the trimming mechanism is assembled with the sewing machine body.

Fig. 17 is an enlarged view of a in fig. 16.

Fig. 18 is a sectional view of the trimming mechanism after the trimming mechanism is assembled with the sewing machine body.

Reference numerals: 1. a frame; 2. a thread cutting mechanism; 3. a presser foot lifting mechanism; 4. a needle pitch adjusting mechanism; 5. a driving motor; 6. a second output shaft; 7. a first output shaft; 8. a first crank; 9. a swinging seat; 10. a first support shaft; 11. the first toggle piece; 12. a first chute; 13. a slide block; 14. a first cam; 15. a duplex swing rod; 16. a first swing arm; 17. a second swing arm; 18. a roller; 19. a second support shaft; 20. the second toggle piece; 21. a second chute; 22. a toggle pin; 23. a second crank; 24. a second cam; 25. a through hole; 26. a rotating end; 27. a protruding end; 28. a rotating shaft; 29. a return spring; 30. a rolling wheel; 31. cutting the spool; 32. a wire cutting crank;

a1, a needle pitch adjusting area; a2, a line cutting area; a3, lifting a presser foot area;

a100, driving a knee rest executing component; a200, a knee rest driving part; a10, a knee rest disc; a20, connecting rods; a30, rotating the block; a40, rotating the rod; a50, connecting frames; a60, a housing; a70, a sensor; a80, a sensed piece; a90, installing a sleeve; a41, a rotating part; a42, a swinging part; a43, a limiting part; a44, a clamp spring groove; a51, mounting holes; a52, waist-shaped holes; a53, side plates; a54, a bottom plate; a91, a mounting groove part; a92, fixing the cap part; a93, a side leaning part; a94, fixing holes; a110, clamping springs; a120, limiting sleeve; a130, torsion springs; a140, shaft sleeve; a150, rubber sleeve;

b1, a bearing seat; b11, a tool rest guide frame; b12, a chute; b13, guiding the sliding block; b14, a cover cap; b15, a sleeve; b16, assembling holes; b2, a cutter assembly; b20, a cutter bar; b21, a guide post; b22, a knife rest; b221, fixing bracket; b222, adjusting the bracket; b23, grooves; b24, an adjusting groove; b25, a cutter; b26, a U-shaped groove; b27, adjusting bolts; b28, a gasket; b29, adjusting the threaded hole; b3, a trimming motor; b31, a motor shaft; b32, a crank connecting rod assembly; b33, a crank sleeve; b34, a connecting rod; b4, a sewing machine shell; b41, a thread needling mechanism; b42, a puncture needle; b43, needle bar; b44, a presser foot lifting mechanism; b45, presser foot; b46, lifting a presser foot bar; b47, needle plate; b48, tungsten steel sheets; b100, an upper shaft motor of the sewing machine.

Detailed Description

The following describes the embodiments of the present utility model in further detail with reference to the accompanying drawings.

As shown in FIG. 1, a sewing machine includes a thread cutting mechanism, a presser foot lifting mechanism, and a stitch length adjusting mechanism. As shown in fig. 2, the thread cutting, presser foot lifting and stitch length adjusting mechanism comprises a frame 1, wherein a thread cutting mechanism 2, a presser foot lifting mechanism 3 and a stitch length adjusting mechanism 4 are arranged on the frame 1; the lower part of the frame 1 is also provided with a driving motor 5. Wherein, the second output shaft 6 of the driving motor 5 extends forward and drives the thread cutting mechanism 2, and the first output shaft 7 of the driving motor 5 extends backward and drives the presser foot lifting mechanism 3 and the stitch length adjusting mechanism 4. Thereby realizing synchronous driving of the thread cutting mechanism 2, the presser foot lifting mechanism 3 and the needle pitch adjusting mechanism 4 through the driving motor 5 and the two output shafts.

Specifically, referring to fig. 2 and fig. 3, the first output shaft 7 is provided with a first crank 8, and the first crank 8 drives the gauge needle adjusting mechanism 4 to move. A first support shaft 10 is arranged on one side of the swing seat 9 of the needle pitch adjusting mechanism 4, and the first support shaft 10 drives the swing seat 9 to swing within a set angle; one end of the first support shaft 10 facing the driving motor is provided with a first stirring piece 11, a first sliding groove 12 is formed in the first stirring piece 11, a sliding block 13 is arranged in the first sliding groove 12, and the outer end of the first crank 8 is provided with the sliding block 13.

Therefore, the driving motor drives the first stirring piece 11 to rotate through the first crank 8 through the design of the sliding groove and the sliding block 13, and when the gauge needle distance adjusting assembly is driven, the inner wall of the first sliding groove 12 can always limit the movement of the sliding block 13, so that the sliding block 13 can only reciprocate in the extending direction of the first sliding groove 12, and further the first crank 8 can be more stable when driving the first stirring piece 11 to rotate, the first stirring piece 11 can also be more stable when driving the gauge needle distance adjusting assembly to move, the error rate of the gauge needle distance adjusting assembly is finally reduced, and the yield of products is improved.

Referring to fig. 2 and 3, a first cam 14 is mounted on the first output shaft 7, and the first cam 14 drives the presser foot lifting mechanism 3. Specifically, a duplex swing rod 15 is rotatably installed on the frame 1, the duplex swing rod 15 is provided with a first swing arm 16 and a second swing arm 17, the swing arm end of the first swing arm 16 is hinged with a presser foot lifting connecting rod, and the swing arm end of the second swing arm 17 is abutted against the first cam 14. The first cam 14 is driven to rotate by the driving motor 5, then the first cam 14 drives the second swing arm 17 to move, the second swing arm 17 drives the first swing arm 16 to move by the main body of the middle part of the duplex swing rod 15, and finally, the first swing arm 16 drives the presser foot lifting mechanism 3 to move.

Referring to fig. 1, fig. 2 and fig. 3, the dual swing rod 15 is disposed below the first toggle member 11, and the first toggle member 11 is located between the first swing arm 16 and the second swing arm 17 of the dual swing rod 15. Therefore, under the condition that the parts are not interfered with each other, the parts are as compact as possible, the installation space is contracted to a smaller range as much as possible, and the whole installation space is further saved.

Referring to fig. 1 and 3, a rotation shaft 28 is disposed on the dual swing link 15, and the dual swing link 15 rotates around the rotation shaft 28. The rotating shaft 28 is provided with a reset spring 29 for resetting the presser foot, one end of the reset spring 29 is arranged on the frame 1, and the other end of the reset spring 29 is arranged on the duplex swing rod 15, so that when the duplex swing rod 15 is driven by the protruding end 27 of the first cam 14 to incline for a certain angle, the presser foot can be lifted or lowered, and the reset spring 29 can be tensioned. When the non-working surface of the duplex swing rod 15, namely the rotating end 26 is contacted with the roller 18, the reset spring 29 drives the self-reset, and simultaneously drives the duplex swing rod 15 to reset, finally, the reset of the presser foot is realized, and the reset structure is simple and effective.

As shown in fig. 3, a roller 18 is hinged to the swing arm end of the second swing arm 17 of the duplex swing arm 15, and the roller 18 abuts against the tread of the first cam 14. Therefore, a part of friction force between the second swing arm 17 and the first cam 14 is normally formed into acting force for rotating the roller 18 through the roller 18, so that movement between the second swing arm 17 and the second cam 24 is smoother, friction force when the second swing arm 17 and the second cam 24 touch together is reduced, and damage caused by scraping of the second swing arm and the first cam is reduced.

With reference to fig. 2 and fig. 3, the first cam 14 includes a rotating end 26 and a protruding end 27, where the rotating end 26 is connected with the first output shaft 7, so as to drive the first cam 14 by the driving motor 5, and the protruding end 27 protrudes outwards to toggle the second swing arm 17, so as to realize movement of the presser foot lifting mechanism 3. The first cam 14 has a working curved surface, i.e., the circumferential surface of the protruding end 27, and a non-working curved surface, i.e., the circumferential surface of the rotating end 26. The diameter of the rotating end 26 is not identical to that of the protruding end 27, so that the double pendulum bar 15 remains fixed against swinging when the first cam 14 rotates and the non-working curved surface of the first cam 14 contacts the roller 18. When the working curved surface is contacted with the roller 18, the convex end 27 pushes the roller 18, so as to drive the duplex swing rod 15 to swing and drive the presser foot lifting mechanism 3 to move.

As shown in fig. 3, a second supporting shaft 19 is disposed on the other side of the swinging seat 9, and the first supporting shaft 10 and the second supporting shaft 19 are disposed on the same axis and extend into two side portions of the swinging seat 9 respectively, so that two ends of the swinging seat 9 are stabilized by the first supporting shaft 10 and the second supporting shaft 19. The first support shaft 10 is also provided with a second stirring piece 20, and the second stirring piece 20 is provided with a second chute 21; a toggle pin 22 is arranged on the side part of the swinging seat 9 adjacent to the first supporting shaft 10, and the toggle pin 22 is arranged in the second sliding groove 21. And the second stirring piece 20 can be more stable when stirring the needle distance adjusting mechanism 4 component through stable sliding of the stirring pin 22 in the second chute 21. The first support shaft 10 can also drive the swinging seat 9 through the toggle pin 22 while supporting the swinging seat 9.

Referring to fig. 2 and 4, the second output shaft 6 is provided with a second crank 23, the second crank 23 is provided with a second cam 24, and the second cam 24 drives a wire cutting shaft 31 and a wire cutting crank 32 of the wire cutting mechanism 2.

The second cam 24 is provided with a through hole 25, one end of the second crank 23 is disposed in the through hole 25, and the working curved surface of the second cam 24 is the inner wall of the through hole 25. In this embodiment, the part of the second crank 23 disposed in the through hole 25 is a rolling wheel 30, after the second crank 23 rotates, the second crank rolls on the working curved surface of the second cam 24 through the rolling wheel 30, so as to drive the second cam 24 to rotate, and then the second cam 24 drives the thread trimming mechanism 2. Therefore, the movement of the rolling wheel 30 is limited by the inner wall of the through hole 25, so that the rolling wheel 30 drives the second cam 24 on the inner side of the second cam 24, the rolling wheel 30 is prevented from being separated from the second cam 24, and the movement between the second cam 24 and the second crank 23 is more stable.

As shown in fig. 1, the driving motor 5 is preferably disposed transversely on the lower side of the middle of the frame 1 in this embodiment, so that the components on two sides of the driving motor 5 can have almost equal installation spaces, so that the components of the thread cutting mechanism 2, the presser foot lifting mechanism 3, the stitch length adjusting mechanism 4 and the like can be more reasonably utilized in the installation space in the frame 1.

The lower part of the frame of the utility model is also provided with a knee rest component, which comprises: a sensor a70 for acquiring a trigger signal; a sensed member a80 for triggering the sensor a70; the knee rest executing component a100 is used for driving the sensed piece a80 to move along a set track; a knee rest driving part a200 for driving the knee rest executing part a100; a connecting frame a50 for being fixed on the adapted sewing machine and directly or indirectly carrying the rest of the components; the knee rest executing part a100 comprises a rotating rod a40 and a mounting sleeve a90; the rotating lever a40 includes: a rotating part a41, a swinging part a42 and a limiting part a43; the rotating part a41, the swinging part a42 and the limiting part a43 are integrally formed; a rotating part a41 rotatably installed on the connection frame a 50; one end of the rotation part a41 extends out of the connection frame a50 and is connected with the knee rest driving part a200 (refer to fig. 6); a swinging part a42 which is provided at the other end of the rotating part a41 and is bent to one side; a limit part a43 arranged at the swinging end of the swinging part a42 and bent towards the other side; the end part of the limiting part a43 stretches into the waist-shaped hole a52 of the connecting frame a 50; the swinging part a42 or the limiting part a43 is provided with the mounting sleeve a90, and the mounting sleeve a90 is provided with the sensed member a80.

The rotating rod a40 is integrally formed, so that signal interference to the sensor is avoided, the structure of the rotating rod is simplified, the strength of the rotating rod is improved, the loosening in the rotating process is avoided, and the service life of the assembly is prolonged; further, because the structure is simplified, the installation difficulty of the assembly is reduced, the installation precision is improved, and the processing cost is reduced.

According to an embodiment of the present utility model, referring to fig. 8, 10 and 11 and 12, the mounting sleeve a90 is provided with a mounting groove fixing portion a91, a fixing cap portion a92 and a side rest portion a93; referring to fig. 8 and 10, the mounting sleeve is disposed at a corner where the swing portion a42 and the limit portion a43 are connected; the fixed cap a92 is sleeved on the limit part a43; the fixing cap portion a92 covers the upper side, the front side and the rear side of the stopper portion a 43. That is, the structure of the fixing cap portion a92 restricts four degrees of freedom between the mounting sleeve a90 and the rotating lever a40, that is, three degrees of freedom of rotation and one degree of freedom of movement between the mounting sleeve a90 and the rotating lever in three directions in right-angle three coordinate axes.

Further, the side rest portion a93 is abutted against the swing portion a42; the side rest part a93 is provided with a fixing hole a94, and is fixed to the swing part a42 by a screw passing through the fixing hole a 94; the mounting sleeve a90 is a plastic piece. As shown in fig. 8, the mounting sleeve a90 can be fixed on the swinging portion a42 by only one screw, that is, the side leaning portion a93 and the fixing hole a94 are matched with the structure of the fixing cap portion a92, so that the position between the mounting sleeve a90 and the rotating rod a40 is completely fixed, and the mounting sleeve a90 and the rotating rod a40 are convenient to install and stable to connect.

Further, the knee rest assembly is used for triggering a pressing signal or a lifting signal of the presser foot lifting mechanism, and referring to fig. 6, the knee rest driving part a200 comprises a knee rest disc a10, a connecting rod a20 and a rotating block a30; the knee rest disc a10 is of a plate-shaped structure; one end of a connecting rod a20 is connected with a knee leaning disc a 10; the rotating block a30 is connected with the other end of the connecting rod a 20; the rotating rod a40 is connected with the rotating block a30 and is arranged vertically to the connecting rod a 20; the rotation of the knee leaning plate a10 can sequentially rotate the connecting rod a20, the rotating block a30 and the rotating rod a40, and drive the sensed piece a80 to trigger the sensing signal of the sensor a 70.

Further, referring to fig. 7, 8 and 10, a rubber sleeve a150 is disposed between the stopper a43 and the waist-shaped hole a52, and the stopper a43 passes through the rubber sleeve a150 to contact with the waist-shaped hole a 52. The rotating rod a40 is in flexible contact with the waist-shaped hole a52 of the connecting frame a50 when the limiting part a43 swings in the rotating process, so that the impact force and impact vibration are reduced, the motion track of the sensed piece a80 is more stable, and the signal precision of the sensor a70 is improved; and the connecting part in the assembly is not easy to loosen, and the service life of the whole assembly is prolonged.

Further, referring to fig. 7 and 10, a circlip groove a44 is formed in the rotating portion a41 near the swinging portion a42; a clamp spring a110 is assembled at the clamp spring groove a44; the connecting frame a50 is provided with a U-shaped bend, the U-shaped bend comprises two side plates a53 and a bottom plate a54, and the mounting hole a51 is formed in the two side plates a 53; the rotating part a41 is also provided with a limit sleeve a120, and the two side plates a53 are arranged between the clamp spring a110 and the limit sleeve a 120.

Specifically, referring to fig. 10, the rotary part a41 further includes a boss a140, and the rotary part a41 is rotatably coupled to the mounting hole a51 through the boss a 140. The shaft sleeve a140 passes through the mounting holes a51 on the two side plates a53 and is positioned between the clamp spring a110 and the limiting sleeve a120, so that the rotating rod a40 is prevented from axially bouncing along the rotating part a41, and the stability of the power rotating process is improved.

Further, referring to fig. 7 and 8, the device further includes a torsion spring a130 disposed between the two side plates a53, one end of the torsion spring a130 abuts against the limiting portion a43, and the other end of the torsion spring a130 abuts against the bottom plate a54; the rotation portion a41 passes through the torsion spring a130. One end of the torsion spring a130 specifically refers to a moment arm where the torsion spring a130 abuts against the limiting portion a43 in fig. 9; the other end of the torsion spring a130 is specifically referred to as another arm of force of the torsion spring a130 against the bottom plate a54 in fig. 7 or 8.

The torsion spring is designed to allow the rotation lever a40 to automatically return after the power of the knee rest driving part a200 is removed.

Further, referring to fig. 10, the sensor a70 and the sensing target a80 are provided in the housing a 60.

According to an embodiment of the present utility model, the sensor a70 is a hall sensor, and is disposed on a circuit board; the sensed piece a80 is a magnet; the mounting sleeve a90 is made of low magnetic conduction material; the rotating rod a40 is an iron rod-shaped body. The utility model is not limited thereto.

As shown in fig. 13 to 15, the trimming mechanism of the sewing machine comprises

A carrying seat b1 arranged on the sewing machine body;

the trimming motor b3 is arranged on the bearing seat b1 and is used for providing power;

the cutter assembly b2 is arranged on the bearing seat b1 and can vertically lift;

the crank connecting rod assembly b32 is arranged in the bearing seat b1, one end of the crank connecting rod assembly b is a power input end b35, and the other end of the crank connecting rod assembly b is a power output end b36; the power input end b35 is connected with a motor shaft b31 of the trimming motor b3, and the power output end b36 is connected with the cutter assembly b 2;

the tool rest guide frame b11 is arranged in the bearing seat b1 and is provided with a vertical chute b12; the power output end b36 is provided with a guide slide block b13, the guide slide block b13 is positioned in the chute b12, and the guide slide block b13 is connected with a guide post b21 of the cutter assembly b 2; the crank link assembly b32 converts the rotation of the motor shaft b31 into the vertical elevation of the cutter assembly b 2.

The cutter assembly b2 is driven by a trimming motor b3, and when the trimming motor b3 is started, the power input end b35 transmits energy to the cutter assembly b2 connected with the power output end b36 through the crank-link assembly b 32.

Since the tool rest guide frame b11 is vertically fixed on the bearing seat b1, the horizontal displacement of the guide slide block b13 is limited by the slide way b12, so that the guide slide block b13 can only reciprocate along the up-down direction. Because the guide slide block b13 is connected with the guide post b12, when the guide post b21 is driven by the power output end b36 to move, the guide slide block b13 simultaneously limits the displacement of the guide post b12 in the horizontal direction, so that the rotation of the motor shaft b31 is changed into the vertical lifting of the cutter assembly b2, the shaking of the cutter assembly b2 is reduced, and the accuracy of the cutter b25 is improved.

As shown in fig. 13-15, crank link assembly b32 includes crank boss b33, link b34, and guide post b21; a crank shaft sleeve b33 is arranged on the motor shaft b31 in a penetrating way, the swing end of the crank shaft sleeve b33 is hinged with the upper end of a connecting rod b34, the lower end of the connecting rod b34 is sleeved on a guide post b21, one end of the guide post b21 is fixedly connected with the upper end of the cutter assembly b2, and the other end of the guide post b21 is connected with a guide sliding block b 13.

When the trimming motor b3 is started, the crank shaft sleeve b33 fixed on the motor shaft b31 through the bolt also rotates along with the motor shaft b31, and drives the guide post b21 to move through the connecting rod b34, and one end of the guide post b21 is connected with the guide slide block b13 positioned in the tool rest guide frame b11, so that the guide post b21 can only move along the direction of the tool rest guide frame b 11.

The other end of the guide post b21 is connected with the cutter bar b20 of the cutter assembly b2, so that when the guide post b21 is driven by the trimming motor b3 and starts to move, the cutter bar b20 is driven to move along the direction of the cutter bar guide frame b11, and the power generated by the trimming motor b3 is transmitted to the cutter assembly b 2.

As shown in fig. 13-15, the cutter assembly b2 is provided with a cutter bar b20 and a cutter holder b22; the tool holder b22 comprises a fixed bracket b221 and an adjusting bracket b222; the fixed bracket b221 is arranged at the lower end of the cutter bar b20, a groove b23 matched with the fixed bracket b221 is formed at the top end of the adjusting bracket b222, and the adjusting bracket b222 is assembled on the fixed bracket b221 through the groove b 23;

the knife rest b22 is used for connecting the knife bar b20 and the cutter b25, one end of the fixed support b221 is connected to the bottom end of the knife bar b20, a groove b23 matched with the fixed support b221 is formed in the top end of the adjusting support b222, and the adjusting support b222 is assembled on the other end of the fixed support b221 through the groove b 23.

The surface of the adjusting bracket b222 is provided with an adjusting groove b24, and a bolt passes through the adjusting groove b24 to screw the fixed bracket b221 and the adjusting bracket b222 into a whole; the lower part of the adjusting bracket b222 is provided with a cutter b25.

In operation, the function of moving the adjusting bracket b222 can be achieved by changing the position of the bolt passing through the adjusting groove b24, and thus the position of the cutter b25 in the left-right direction can be adjusted.

As shown in fig. 15-18, a U-shaped groove b26 is formed at the top end of a cutter b25, a plurality of adjusting threaded holes b29 are formed in an adjusting bracket b222, an adjusting bolt b27 penetrates through the U-shaped groove b26 to be assembled into the adjusting threaded holes b29, and a gasket b28 is arranged between the adjusting bolt b27 and the U-shaped groove b 26;

the screw connection among the cutter b25, the gasket b28 and the adjusting bracket b22 is realized through the adjusting bolt b27, and the cutter b25 is fixed on the adjusting bracket b22, so that the cutter b25 can move along with the cutter assembly b 2.

After the adjusting bolt b27 is fastened, the washer b28 is used for pressing the U-shaped groove b26 formed at the top end of the cutter b25, so that the cutter b25 is fixed. The adjusting bolt b27 can be installed to the adjusting threaded holes b29 with different heights to realize the function of adjusting the height of the cutter b25, and in the process of adjusting the cutter b25, the cutter b25 can be positioned more accurately because the upper end of the cutter assembly b2 is limited by the cutter rest guide frame and displacement in the front-back direction cannot occur easily. The gasket b28 is provided with a plurality of holes, and the U-shaped groove b26 can be matched with the gasket to facilitate the installation of the adjusting bolt b 27.

When the cutter b25 is installed on different types of sewing machines, the height of the cutter b25 needs to be adjusted, and the cutter b25 can be fixed on the adjusting bracket b222 by connecting the adjusting bolt b27 to the adjusting threaded hole b29 with different heights and changing the position of the gasket b 28.

As shown in fig. 13 and 14, the width of the fixing bracket b221 is smaller than the distance between the needle bar b43 and the presser foot lifting bar b46, so that the fixing bracket b221 protrudes from between the needle bar b43 and the presser foot lifting bar b 46.

In order to reduce the cost required by upgrading the sewing machine on the market, the utility model has a single structure, and can realize the upgrading and reconstruction of the sewing machine by being arranged on the existing sewing machine shell b4 without specially manufacturing a novel sewing machine to put into production. The width of the fixing bracket b221 should be smaller than the distance between the needle bar b43 and the presser foot lifting bar b46, so that the installation is convenient and the normal operation of the sewing machine is not affected.

Because the independent trimming motor b3 is adopted, the trimming mechanism is in transmission separation with other mechanisms, and mutual interference is reduced. The controller can be utilized to synchronously send signals to the trimming motor b3 of the trimming mechanism and the driving motor of the sewing machine, so that the synchronization of the presser foot lifting action, the thread needling action and the trimming action is realized, and the accuracy and the stability of the sewing machine in working are improved.

As shown in fig. 17 and 18, the cutter b25 is abutted against the tungsten steel sheet b48 inside the needle plate 47, the substantial effect of the tungsten steel sheet b48 at this point is to fix the cutter, and correspondingly, the tungsten steel sheet b48 is replaced by the rest of wear-resistant hard metal material, which is also an equivalent replacement. The tungsten steel sheet b48 made of tungsten steel has good wear resistance due to the high hardness and strength of the tungsten steel, corrosion resistance, rust resistance and the like, so that the abrasion of the needle plate b47 caused by frequent up-and-down movement of the cutter b25 is reduced, the positioning effect on the cutter b25 can be realized, and the appearance of a finished product is improved.

As shown in fig. 16 and 18, the carrier b1 is an end cover of the sewing machine;

the bearing seat b1 is arranged on the sewing machine shell b 4.

The bearing seat b1 can be connected to the sewing machine shell b4 in an end cover mode, so that the cost of upgrading and reforming the existing sewing machine can be reduced, meanwhile, the assembly of the trimming mechanism of the sewing machine is completed without affecting the overall attractive appearance of the sewing machine, and excessive space is not required to be occupied.

The cutter bar b20 is sleeved with a sleeve b15, and the cutter bar b20 passes through the sleeve b15 and penetrates out of the assembly hole b 16.

Through sleeve b15, can further reduce the rocking of cutter arbor b20, reduce cutter unit b 2's displacement, improve cutter unit b 2's degree of accuracy, sleeve b15 can protect cutter arbor b20 not bump with mounting hole b16 simultaneously, reduces cutter arbor b20 because of the loss that rubs and takes place.

The trimming motor b3 is transversely arranged, and the motor shaft b31 is parallel to the main shaft of the sewing machine.

The motor shaft b31 of the trimming motor b3 is parallel to the main shaft of the sewing machine, so that the reciprocating stroke among the cutter action, the needling action and the presser foot lifting action is equivalent, the frequency between the trimming motor b3 and the sewing machine motor is synchronized through the controller, and the phenomenon that the sewing machine cannot work normally due to different frequencies between the cutter action and other actions is avoided.

As shown in fig. 16 and 18, a housing b14 is arranged on the bearing seat b1, and the housing b14 is used for protecting the trimming motor b3; the housing b14, the bearing seat b1 and the sewing machine shell b4 are connected through bolts.

The trimming motor b3 is arranged in the housing b14, the housing is arranged behind the bearing seat b1 to facilitate the installation of the trimming motor b3, the trimming motor b3 can be protected, the power is transmitted to the cutter assembly b2 through the crank connecting rod assembly b32 in the bearing seat b1 to drive the cutter assembly b2 to move, and the housing b14, the bearing seat b1 and the sewing machine shell b4 are connected through bolts, so that the mounting is facilitated, and the fixing can be well provided.

As shown in fig. 13, the holder guide b11 is a separate component from the carrier b 1; accordingly, those skilled in the art will recognize that the present application does not exclude that the tool holder guide b11 and the carrier b1 are integrally formed, and that the tool holder guide b11 is formed at a corresponding portion of the carrier b 1.

The foregoing has shown and described the basic principles and main features of the present utility model and the advantages of the present utility model. It will be understood by those skilled in the art that the present utility model is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present utility model, and various changes and modifications may be made without departing from the spirit and scope of the utility model, which is defined in the appended claims. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims

1. The sewing machine comprises a frame, and a stitch length adjusting mechanism, a thread trimming mechanism and a presser foot lifting mechanism which are arranged on the frame, and is characterized in that a driving motor (5) is arranged at the lower part of the frame, a first output shaft (7) of the driving motor is used for driving a swinging seat (9) of the stitch length adjusting mechanism (4),

one side of the swinging seat (9) is provided with a first supporting shaft (10), and one end of the first supporting shaft (10) drives the swinging seat (9) to swing in a set angle; the other end of the first supporting shaft (10) extends towards the position of the driving motor and is provided with a first stirring piece (11), and a first sliding groove (12) is formed in the first stirring piece (11); the first output shaft (7) is provided with a first crank (8), the first crank (8) is provided with a sliding block (13), and the sliding block (13) slides in the first sliding groove (12).

2. A sewing machine according to claim 1, characterized in that the first support shaft (10) and the first output shaft (7) are arranged up and down in a vertical plane and in a front-to-back arrangement in a horizontal plane; the sliding block (13) is rotatably arranged at the swinging end of the first crank (8).

3. A sewing machine according to claim 1, characterized in that the other side of the oscillating seat (9) is provided with a second support shaft (19); the first support shaft (10) and the second support shaft (19) are arranged on the same axis and extend into two side parts of the swing seat (9) respectively;

the first support shaft (10) is also provided with a second stirring piece (20), and the second stirring piece (20) is provided with a second chute (21);

the side part of the swinging seat (9) close to the first supporting shaft (10) is provided with a poking pin (22), and the poking pin (22) is arranged in the second sliding groove (21).

4. A sewing machine as defined in any of claims 1-3, wherein the presser foot lifting mechanism comprises:

a first cam (14) mounted on the first output shaft (7);

the duplex swing rod (15) is rotatably arranged on the frame (1); the duplex swing rod (15) is provided with a first swing arm (16) and a second swing arm (17); the swing arm end of the first swing arm (16) is hinged with a presser foot lifting connecting rod, and the swing arm end of the second swing arm (17) is propped against the first cam (14).

5. A sewing machine according to claim 4, characterized in that the double pendulum bar (15) is arranged below the first toggle member (11), and the first toggle member (11) is located between the first swing arm (16) and the second swing arm (17) of the double pendulum bar (15);

a rotating shaft (28) is arranged on the duplex swing rod (15) in a penetrating way, and the duplex swing rod (15) rotates around the rotating shaft (28);

the rotating shaft (28) is provided with a reset spring (29) for resetting the presser foot, one end of the reset spring (29) is arranged on the frame (1), and the other end of the reset spring is arranged on the duplex swing rod (15).

6. A sewing machine according to claim 4, characterized in that the first cam (14) comprises a rotating end (26) and a projecting end (27), the rotating end (26) of which is connected to the first output shaft (7), the projecting end (27) being adapted to toggle the second swing arm (17);

the first cam (14) has a working curved surface, which is the peripheral surface of the protruding end (27), and a non-working curved surface, which is the peripheral surface of the rotating end (26).

7. A sewing machine according to any of claims 1-3, characterized in that the second output shaft (6) of the drive motor (5) extends forward and drives the thread cutting mechanism (2),

a first output shaft (7) of the driving motor (5) extends backwards and drives the presser foot lifting mechanism (3) and the needle pitch adjusting mechanism (4);

the thread cutting mechanism comprises:

a second cam (24) for driving the thread cutting shaft (31) and the thread cutting crank (32);

the second cam (24) is provided with a through hole (25); one end of the second crank (23) is arranged in the through hole (25), and the working curved surface of the second cam (24) is the inner wall of the through hole (25);

a second crank (23) mounted on a second output shaft (6) of the drive motor; the second crank (23) is used for driving the second cam (24).

8. A sewing machine as defined in claim 1, wherein the lower portion of the frame is provided with a knee rest assembly comprising:

a sensor (a 70) for acquiring a trigger signal;

a sensed member (a 80) for triggering the sensor (a 70);

a knee rest executing component (a 100) for driving the sensed piece (a 80) to move along a set track;

a knee rest driving part (a 200) for driving the knee rest executing part (a 100);

a connecting frame (a 50) for being fixed on an adapted sewing machine and directly or indirectly carrying the rest of the components;

the knee rest executing component (a 100) comprises a rotating rod (a 40) and a mounting sleeve (a 90);

the rotating lever (a 40) includes: a rotation part (a 41), a swinging part (a 42) and a limit part (a 43); the rotating part (a 41), the swinging part (a 42) and the limiting part (a 43) are integrally formed;

a rotating part (a 41) rotatably mounted on the connecting frame (a 50); one end of the rotating part (a 41) extends out of the connecting frame (a 50) and is connected with the knee rest driving part (a 200);

a swinging part (a 42) which is arranged at the other end of the rotating part (a 41) and is bent to one side;

a limit part (a 43) which is arranged at the swinging end of the swinging part (a 42) and is bent towards the other side; the end part of the limiting part (a 43) extends into a waist-shaped hole (a 52) of the connecting frame (a 50);

the swinging part (a 42) or the limiting part (a 43) is provided with the mounting sleeve (a 90), and the mounting sleeve (a 90) is provided with the sensed piece (a 80);

the mounting sleeve (a 90) is provided with a mounting groove fixing part (a 91), a fixing cap part (a 92) and a side leaning part (a 93);

the mounting sleeve is arranged at a corner where the swinging part (a 42) and the limiting part (a 43) are connected;

a fixed cap part (a 92) sleeved on the limit part (a 43);

a side rest part (a 93) which is abutted against the swing part (a 42);

the side leaning part (a 93) is provided with a fixing hole (a 94), and the side leaning part is fixed on the swinging part (a 42) through the fixing hole (a 94) by a screw;

the mounting sleeve (a 90) is a plastic piece.

9. A sewing machine according to claim 1, characterized in that the end cap of the frame front forms a carrier (b 1); the bearing seat (b 1) is provided with a trimming motor (b 3), a cutter assembly (b 2), a crank connecting rod assembly (b 32) and a cutter rest guide frame (b 11);

the cutter assembly (b 2) is arranged on the bearing seat (b 1) and can vertically lift; the crank connecting rod assembly (b 32) is arranged in the bearing seat (b 1), one end of the crank connecting rod assembly is a power input end (b 35), and the other end of the crank connecting rod assembly is a power output end (b 36); the power input end (b 35) is connected with a motor shaft (b 31) of the trimming motor (b 3), and the power output end (b 36) is connected with the cutter assembly (b 2); the tool rest guide frame (b 11) is arranged in the bearing seat (b 1) and is provided with a vertical chute (b 12); the power output end (b 36) is provided with a guide sliding block (b 13), the guide sliding block (b 13) is positioned in the sliding groove (b 12), and the guide sliding block (b 13) is connected with a guide pillar (b 21) of the cutter assembly (b 2); the crank-link assembly (b 32) converts the rotation of the motor shaft (b 31) into the vertical elevation of the cutter assembly (b 2).

10. A sewing machine according to claim 9, characterized in that the crank-link assembly (b 32) comprises a crank sleeve (b 33), a link (b 34) and the guide post (b 21); the motor shaft (b 31) is provided with the crank shaft sleeve (b 33) in a penetrating way, the swing end of the crank shaft sleeve (b 33) is hinged with the upper end of the connecting rod (b 34), the lower end of the connecting rod (b 34) is sleeved on the guide post (b 21), one end of the guide post (b 21) is fixedly connected with the upper end of the cutter assembly (b 2), and the other end of the guide post (b 21) is connected with the guide slide block (b 13);

the cutter assembly (b 2) is provided with a cutter bar (b 20) and a cutter rest (b 22); the tool rest (b 22) comprises a fixed bracket (b 221) and an adjusting bracket (b 222); the fixed support (b 221) is arranged at the lower end of the cutter bar (b 20), a groove (b 23) matched with the fixed support (b 221) is formed at the top end of the adjusting support (b 222), and the adjusting support (b 222) is assembled on the fixed support (b 221) through the groove (b 23);

an adjusting groove (b 24) is formed in the surface of the adjusting bracket (b 222), and a bolt penetrates through the adjusting groove (b 24) to enable the fixing bracket (b 221) and the adjusting bracket (b 222) to be connected into a whole in a threaded mode;

the lower part of the adjusting bracket (b 222) is provided with a cutter (b 25).