Presser foot and thread trimming device and sewing machine

Abstract

The present application belongs to sewing equipment technical field, and particularly to a lifting presser foot and thread trimming device and sewing machine. The lifting presser foot and thread trimming device is that a thread trimming lifting presser foot crank is arranged on the output shaft of the driving motor, one end of the thread trimming lifting presser foot crank is fixedly connected with the output shaft, and the other end is arranged in suspension, the thread trimming lifting presser foot crank is drivingly connected with the lifting presser foot transmission mechanism and the lifting presser foot mechanism through the lifting presser foot transmission mechanism, and the thread trimming lifting presser foot crank is drivingly connected with the thread trimming mechanism through the thread trimming transmission mechanism; when the output shaft of the driving motor rotates clockwise, the thread trimming lifting presser foot crank drives the lifting presser foot transmission mechanism to act, and finally drives the lifting presser foot mechanism to act, and the thread trimming mechanism does not act; when the output shaft of the driving motor rotates counterclockwise, the thread trimming lifting presser foot crank drives the thread trimming transmission mechanism to act, and finally drives the thread trimming mechanism to act, and the lifting presser foot mechanism does not act; the present application drives the lifting presser foot and the thread trimming by the driving motor respectively, simplifies the structure, reduces the cost, and has high transmission efficiency and good stability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of sewing equipment, in particular to a presser foot lifting and thread trimming device and sewing machine. BACKGROUND

[0002] The sewing machine is a machine that uses one or more sewing threads to form one or more stitches on the sewing material, so as to interweave or sew together one or more layers of the sewing material. At present, most of the sewing machines are provided with an automatic presser foot lifting device. By controlling the lifting and falling of the presser foot, the sewing thread is arranged on the sewing material to realize sewing.

[0003] The sewing machine comprises a presser foot lifting mechanism and a thread trimming mechanism. The existing presser foot lifting mechanism and thread trimming mechanism are driven by independent power elements, resulting in high cost and complex structure. SUMMARY

[0004] The purpose of the present application is to provide a presser foot lifting and thread trimming device and sewing machine with simplified structure and reduced cost.

[0005] The present application is implemented as follows:

[0006] One purpose of the present application is to provide a presser foot lifting and thread trimming device, comprising a presser foot lifting mechanism, a thread trimming mechanism and a driving motor. A thread trimming and presser foot crank is arranged on the output shaft of the driving motor. One end of the thread trimming and presser foot crank is fixedly connected with the output shaft, and the other end is suspended. The thread trimming and presser foot crank is drivingly connected with the presser foot lifting mechanism through a presser foot lifting transmission mechanism, and is drivingly connected with the thread trimming mechanism through a thread trimming transmission mechanism. When the output shaft of the driving motor rotates clockwise, the thread trimming and presser foot crank drives the presser foot lifting transmission mechanism to act, and finally drives the presser foot lifting mechanism to act. The thread trimming mechanism does not act. When the output shaft of the driving motor rotates counterclockwise, the thread trimming and presser foot crank drives the thread trimming transmission mechanism to act, and finally drives the thread trimming mechanism to act. The presser foot lifting mechanism does not act.

[0007] In the above-mentioned presser foot lifting mechanism, the presser foot lifting transmission mechanism comprises a presser foot shaft, a first presser foot crank and a second presser foot crank. One end of the first presser foot crank is fixedly connected with the presser foot shaft, and the other end is suspended. One end of the second presser foot crank is fixedly connected with the presser foot shaft, and the other end is connected with the presser foot mechanism. When the output shaft rotates clockwise, the thread trimming and presser foot crank rotates towards the first presser foot crank and is driven to abut on the first presser foot crank shaft to drive the presser foot shaft and the second presser foot crank to swing counterclockwise to lift the presser foot. When the output shaft rotates counterclockwise, the thread trimming and presser foot crank rotates away from the first presser foot crank, and is not connected with the first presser foot crank.

[0008] In the presser foot lifting mechanism, the first roller or the first shaft sleeve is arranged on one side of the thread trimming lifting crank close to the first presser foot lifting crank, is arranged on the first presser foot lifting crank through the shaft position screw, and can abut against the first presser foot lifting crank.

[0009] In the presser foot lifting mechanism, the presser foot lifting mechanism comprises a presser foot lifting rod, the upper end of the presser foot lifting rod is hingedly connected with a first connecting end of a presser foot rear lever, the lower end of the presser foot lifting rod is connected with a second presser foot lifting crank, the presser foot rear lever is rotationally connected with a machine shell through a second connecting end, a third connecting end of the presser foot rear lever is connected with a first connecting end of a presser foot front lever through a presser foot pulling rod, the presser foot front lever is rotationally connected with the machine shell through a second connecting end, a third connecting end of the presser foot front lever is connected with a presser foot lifting plate and a presser bar guide frame, and the presser bar guide frame is connected with a presser bar.

[0010] In the presser foot lifting mechanism, the second presser foot lifting crank is provided with an open slot, and the lower end of the presser foot lifting rod is arranged in the open slot and is rotationally connected with the second presser foot lifting crank through a pin shaft.

[0011] In the presser foot lifting mechanism, the thread trimming transmission mechanism comprises a thread trimming connecting rod, a thread trimming driving shaft, a first thread trimming crank and a thread trimming driving crank connected with a thread trimming mechanism, one end of the first thread trimming crank is fixedly connected with the thread trimming driving shaft, and the other end is arranged in a suspended manner, one end of the thread trimming connecting rod is hingedly connected with the suspended end of the thread trimming lifting crank, and the other end is hingedly connected with the suspended end of the first thread trimming crank, the thread trimming driving shaft is further provided with a second thread trimming crank, one end of the second thread trimming crank is fixedly connected with the thread trimming driving shaft, and the other end is arranged in a suspended manner, when the thread trimming driving shaft rotates clockwise, the second thread trimming crank drives the thread trimming driving crank to rotate, and finally drives the thread trimming mechanism to act, when the thread trimming driving shaft rotates counterclockwise, the second thread trimming crank rotates away from the thread trimming driving crank, and is not connected with the thread trimming driving crank.

[0012] In the presser foot lifting mechanism, the second thread trimming crank is provided with a second roller or a second shaft sleeve, the second roller or the second shaft sleeve is connected with the second thread trimming crank through a pin shaft, and can abut against the thread trimming driving crank.

[0013] In the presser foot lifting mechanism, the thread trimming mechanism comprises a thread trimming shaft, the thread trimming shaft is provided with a cutter driving crank at one end, one end of the cutter driving crank is fixedly connected with the thread trimming shaft, and the other end is hingedly connected with one end of a long connecting rod, the other end of the long connecting rod is connected with a movable cutter holder, the movable cutter holder is provided with a movable cutter, a fixed cutter for trimming thread is arranged on the machine shell on the side of the movable cutter, and the cutter driving crank is arranged on the thread trimming shaft.

[0014] In the presser foot lifting mechanism, the driving motor is a step motor.

[0015] Another object of the present application is to provide a sewing machine comprising the presser foot lifting mechanism and the thread cutting mechanism.

[0016] The present application has the following advantages over the prior art:

[0017] 1. The driving motor drives the presser foot lifting mechanism and the thread cutting mechanism respectively, which simplifies the structure, reduces the cost, and has high transmission efficiency and good stability.

[0018] 2. The present application can control the height of the presser foot by controlling the rotation angle of the output shaft of the driving motor, and can be applied to sewing occasions with different thicknesses of powder.

[0019] 3. The thread cutting presser foot crank is in contact with the first presser foot crank and the second thread cutting crank, which greatly reduces the assembly difficulty between the parts. DETAILED DESCRIPTION:

[0020] Figure 1 is one of the schematic diagrams of the present application;

[0021] Figure 2 is the second schematic diagram of the present application.

[0022] In the figure: 1, driving motor; 2, output shaft; 3, thread cutting presser foot crank; 4, presser foot shaft; 5, first presser foot crank; 6, second presser foot crank; 7, first shaft sleeve; 8, presser foot top rod; 9, presser foot rear lever; 10, presser foot pull rod; 11, presser foot front lever; 12, presser foot lifting plate; 13, presser rod guide; 14, presser rod; 15, presser foot; 16, open slot; 17, pin shaft; 18, thread cutting connecting rod; 19, thread cutting driving shaft; 20, first thread cutting crank; 21, thread cutting driving crank; 22, second thread cutting crank; 23, second shaft sleeve; 24, thread cutting shaft; 25, cutter driving crank; 26, long connecting rod; 27, movable knife holder; 28, moving knife; 29, fixed knife. DETAILED DESCRIPTION:

[0023] The present application will be further described below with specific embodiments, referring to Figure 1 -2:

[0024] One objective of this invention is to provide a pressing foot lifting and wire cutting device, which includes a pressing foot lifting mechanism, a wire cutting mechanism, and a drive motor 1. A wire-cutting pressing foot lifting crank 3 is mounted on the output shaft 2 of the drive motor 1. One end of the wire-cutting pressing foot lifting crank 3 is fixedly connected to the output shaft 2, while the other end is suspended. The wire-cutting pressing foot lifting crank 3 is connected to the pressing foot lifting mechanism via a pressing foot lifting transmission mechanism, and is also connected to the wire cutting mechanism via a wire cutting transmission mechanism. When the output shaft 2 of the drive motor 1 rotates clockwise, the wire-cutting pressing foot lifting crank 3 rotates with the output shaft 2, driving the pressing foot lifting transmission mechanism to actuate and ultimately causing the pressing foot lifting mechanism to lift the pressing foot. At this time, the wire cutting mechanism does not operate. When the output shaft 2 of the drive motor 1 rotates counterclockwise, the wire-cutting pressing foot lifting crank 3 rotates with the output shaft 2, driving the wire cutting transmission mechanism to actuate and ultimately causing the wire cutting mechanism to actuate and cut the wire. At this time, the pressing foot lifting mechanism does not operate.

[0025] This invention utilizes a drive motor 1 to independently drive the lifting of the pressure foot and the wire cutting action, without interference, effectively saving overall volume, optimizing the structure, reducing costs, and providing high transmission efficiency and good stability. In this invention, the drive motor 1 is preferably a stepper motor. Of course, a servo motor or other suitable motor can also be used.

[0026] Specifically, the lifting foot transmission mechanism of the present invention includes a lifting foot shaft 4, a first lifting foot crank 5, and a second lifting foot crank 6. One end of the first lifting foot crank 5 is fixedly connected to the lifting foot shaft 4, and the other end is suspended. One end of the second lifting foot crank 6 is fixedly connected to the lifting foot shaft 4, and the other end is connected to the foot mechanism. When the output shaft 2 rotates clockwise, it drives the wire-cutting lifting foot crank 3 to rotate toward the first lifting foot crank 5 and abut against the first lifting foot crank 5, driving the lifting foot shaft 4 and the second lifting foot crank 6 to swing counterclockwise to lift the foot. When the output shaft 2 rotates counterclockwise, the wire-cutting lifting foot crank 3 rotates away from the first lifting foot crank 5 and is not connected to the first lifting foot crank 5, and the lifting foot shaft 4 will not rotate.

[0027] like Figure 2 As shown, a first roller or first bushing 7 is provided on the side of the wire-cutting lifting foot crank 3 near the first lifting foot crank 5. The first roller or first bushing 7 is mounted on the first lifting foot crank 5 by a shaft screw, and the first roller or first bushing 7 can abut against the first lifting foot crank 5. The first roller or first bushing 7 can roll in contact with the corresponding surface of the first lifting foot crank 5. The friction between the first roller or first bushing 7 and the first lifting foot crank 5 is small, and no jamming will occur when they abut.

[0028] Specifically, the presser-lifting mechanism comprises a presser-lifting rod 8, the upper end of which is hingedly connected to the first connecting end of a presser-lifting rear lever 9, and the lower end of which is connected to the second presser-lifting crank 6, the presser-lifting rear lever 9 is rotationally connected to the machine shell through the second connecting end, the third connecting end of the presser-lifting rear lever 9 is connected to the first connecting end of a presser-lifting front lever 11 through a presser-lifting pull rod 10, the presser-lifting front lever 11 is rotationally connected to the machine shell through the second connecting end, the third connecting end of the presser-lifting front lever 11 is connected to a presser-lifting guide 13 through a presser-lifting lifting plate 12, and the presser-lifting guide 13 is connected to a presser bar 14. The lower end of the presser bar 14 is provided with a presser foot 15.

[0029] As shown in Figure 1 and Figure 2 , the other end of the second presser-lifting crank 6 is connected to the specific structure of the presser-lifting mechanism: the second presser-lifting crank 6 is provided with an open slot 16, and the lower end of the presser-lifting rod 8 is arranged in the open slot 16 and rotationally connected to the second presser-lifting crank 6 through a pin shaft 17.

[0030] When the presser foot is lifted, the second presser-lifting crank 6 lifts the presser-lifting rod 8.

[0031] The present application can control the height of the presser foot by controlling the rotation angle of the output shaft 2 of the driving motor 1, so as to be suitable for sewing occasions of different thickness of fabrics.

[0032] As shown in Figure 1 and Figure 2 , the thread-cutting transmission mechanism comprises a thread-cutting connecting rod 18, a thread-cutting driving shaft 19, a first thread-cutting crank 20, and a thread-cutting driving crank 21 connected to the thread-cutting mechanism, one end of the first thread-cutting crank 20 is fixedly connected to the thread-cutting driving shaft 19, and the other end is provided as a free end, one end of the thread-cutting connecting rod 18 is hingedly connected to the free end of the thread-cutting presser-lifting crank 3, and the other end is hingedly connected to the free end of the first thread-cutting crank 20, a second thread-cutting crank 22 is also arranged on the thread-cutting driving shaft 19, one end of the second thread-cutting crank 22 is fixedly connected to the thread-cutting driving shaft 19, and the other end is provided as a free end, when the thread-cutting driving shaft 19 rotates clockwise, the second thread-cutting crank 22 drives the thread-cutting driving crank 21 to rotate, and finally drives the thread-cutting mechanism to act, when the thread-cutting driving shaft 19 rotates counterclockwise, the second thread-cutting crank 22 rotates away from the thread-cutting driving crank 21, and is not connected to the thread-cutting driving crank 21.

[0033] In order to prevent jamming, a second roller or a second shaft sleeve 23 is arranged on the second thread-cutting crank 22, the second roller or the second shaft sleeve 23 is connected to the second thread-cutting crank 22 through a pin shaft, and the second roller or the second shaft sleeve 23 can abut against the thread-cutting driving crank 21.

[0034] When the thread is cut, the second roller or the second sleeve 23 is driven against the thread cutting driving crank 21

[0035] Specifically, the thread cutting mechanism comprises a thread cutting shaft 24 which is arranged in parallel with the thread cutting driving shaft 19. A cutter driving crank 25 is arranged at one end of the thread cutting shaft 24, one end of the cutter driving crank 25 is fixedly connected with the thread cutting shaft 24, and the other end is hingedly connected with one end of a long connecting rod 26, the other end of the long connecting rod 26 is connected with a movable cutter holder 27, a movable cutter 28 is arranged on the movable cutter holder 27, a fixed cutter 29 which cooperates with the movable cutter 28 to cut the thread is arranged on the side of the machine housing of the movable cutter 28, and the thread cutting driving crank 21 is arranged on the thread cutting shaft 24.

[0036] Another object of the present application is to provide a sewing machine comprising the above-mentioned presser foot lifting device and thread cutting device.

[0037] The above-mentioned embodiment is only one of the preferred embodiments of the present application, and does not limit the scope of the present application, therefore: any equivalent changes made in shape, structure and principle according to the present application should be covered within the protection scope of the present application.

Claims

1. A presser foot and thread trimming device comprising a presser foot mechanism, a thread trimming mechanism, a drive motor (1), characterized in that: The output shaft (2) of the driving motor (1) is provided with a thread cutting and presser foot lifting crank (3), one end of which is fixedly connected with the output shaft (2) and the other end of which is suspended, the thread cutting and presser foot lifting crank (3) is in transmission connection with a presser foot lifting mechanism through a presser foot lifting transmission mechanism and in transmission connection with a thread cutting mechanism through a thread cutting transmission mechanism; when the output shaft (2) of the driving motor (1) rotates clockwise, the thread cutting and presser foot lifting crank (3) drives the presser foot lifting transmission mechanism to act and finally drives the presser foot mechanism to act, and the thread cutting mechanism does not act; when the output shaft (2) of the driving motor (1) rotates counterclockwise, the thread cutting and presser foot lifting crank (3) drives the thread cutting transmission mechanism to act and finally drives the thread cutting mechanism to act, and the presser foot mechanism does not act.

2. A presser foot and thread trimming device according to claim 1, wherein: The thread cutting transmission mechanism comprises a thread cutting connecting rod (18), a thread cutting driving shaft (19), a first thread cutting crank (20), a thread cutting driving crank (21) connected with the thread cutting mechanism, one end of the first thread cutting crank (20) is fixedly connected with the thread cutting driving shaft (19) and the other end of the first thread cutting crank (20) is suspended, one end of the thread cutting connecting rod (18) is hingedly connected with the suspended end of the thread cutting and presser foot lifting crank (3) and the other end of the thread cutting connecting rod (18) is hingedly connected with the suspended end of the first thread cutting crank (20), a second thread cutting crank (22) is further arranged on the thread cutting driving shaft (19), one end of the second thread cutting crank (22) is fixedly connected with the thread cutting driving shaft (19) and the other end of the second thread cutting crank (22) is suspended, when the thread cutting driving shaft (19) rotates clockwise, the second thread cutting crank (22) drives the thread cutting driving crank (21) to rotate and finally drives the thread cutting mechanism to act, when the thread cutting driving shaft (19) rotates counterclockwise, the second thread cutting crank (22) rotates away from the thread cutting driving crank (21) and is not connected with the thread cutting driving crank (21), a second roller or a second shaft sleeve (23) is arranged on the second thread cutting crank (22), the second roller or the second shaft sleeve (23) is connected with the second thread cutting crank (22) through a pin shaft and can abut against the thread cutting driving crank (21). The presser foot lifting transmission mechanism comprises a presser foot shaft (4), a first presser foot crank (5) and a second presser foot crank (6), one end of the first presser foot crank (5) is fixedly connected with the presser foot shaft (4) and the other end of the first presser foot crank (5) is suspended, one end of the second presser foot crank (6) is fixedly connected with the presser foot shaft (4) and the other end of the second presser foot crank (6) is connected with a presser foot mechanism, when the output shaft (2) rotates clockwise, the thread cutting and presser foot lifting crank (3) rotates towards the first presser foot crank (5) and abuts against the first presser foot crank (5) to drive the presser foot shaft (4) and the second presser foot crank (6) to swing counterclockwise to lift the presser foot, when the output shaft (2) rotates counterclockwise, the thread cutting and presser foot lifting crank (3) rotates away from the first presser foot crank (5) and is not connected with the first presser foot crank (5).

3. A presser foot and thread trimming device according to claim 2, wherein: The first roller or first shaft sleeve (7) is arranged on the side of the thread trimming and presser foot lifting crank (3) close to the first presser foot lifting crank (5), and is arranged on the first presser foot lifting crank (5) through an axial screw, and can abut against the first presser foot lifting crank (5).

4. A presser foot and thread trimming device according to claim 2 or 3, characterised in that: The presser foot lifting mechanism comprises a presser foot lifting rod (8), the upper end of the presser foot lifting rod (8) is hingedly connected with a first connecting end of a presser foot lifting rear lever (9), the lower end of the presser foot lifting rod (8) is connected with a second presser foot lifting crank (6), the presser foot lifting rear lever (9) is rotatably connected with the machine shell through a second connecting end, a third connecting end of the presser foot lifting rear lever (9) is connected with a first connecting end of a presser foot lifting front lever (11) through a presser foot lifting rod (10), the presser foot lifting front lever (11) is rotatably connected with the machine shell through a second connecting end, a third connecting end of the presser foot lifting front lever (11) is connected with a presser foot lifting rod guide (13) through a presser foot lifting plate (12), and the presser foot lifting rod guide (13) is connected with a presser foot lifting rod (14).

5. A presser foot and thread trimming device according to claim 4, wherein: The second presser foot lifting crank (6) is provided with an open slot (16), the lower end of the presser foot lifting rod (8) is arranged in the open slot (16) and is rotatably connected with the second presser foot lifting crank (6) through a pin shaft (17).

6. The presser foot and thread trimming device according to claim 1, wherein: The thread trimming mechanism comprises a thread trimming shaft (24), the thread trimming shaft (24) is provided with a cutter driving crank (25) at one end, one end of the cutter driving crank (25) is fixedly connected with the thread trimming shaft (24), the other end of the cutter driving crank (25) is hingedly connected with one end of a long connecting rod (26), the other end of the long connecting rod (26) is connected with a movable cutter holder (27), the movable cutter holder (27) is provided with a moving cutter (28), a fixed cutter (29) for cooperating with the moving cutter (28) to trim the thread is arranged on the machine shell at one side of the moving cutter (28), and the thread trimming driving crank (21) is arranged on the thread trimming shaft (24).

7. The presser foot and thread trimming device according to claim 1, wherein: The driving motor (1) is a step motor.

8. A sewing machine characterized by: The presser foot lifting and thread trimming device comprises the presser foot lifting and thread trimming device according to any one of claims 1-7. The presser foot lifting and thread trimming device comprises the presser foot lifting and thread trimming device according to any one of claims 1-7.

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