Thread clamping and cutting device and sewing machine

Abstract

The application discloses a thread clamping and cutting device and a sewing machine, which comprises a mounting seat, a sliding plate, a thread clamping plate, a thread cutting plate, a transmission plate and a driving rod. The mounting seat is fixed to the sewing machine and located below a needle plate. The sliding plate is movably connected to the mounting seat. The thread clamping plate is installed on the sliding plate. The thread cutting plate is installed on the sliding plate. The transmission plate is connected with the thread clamping plate and the thread cutting plate. The driving rod is connected with the transmission plate. The driving rod drives the transmission plate to move. In the process that the driving rod moves from the first end to the second end of the stroke, the thread clamping plate, the thread cutting plate and the sliding plate are sequentially driven to move to realize the actions of clamping the sewing thread, cutting the sewing thread and moving the sliding plate from the initial position to the avoiding position in the moving direction of the driving rod. By sequentially clamping and cutting the sewing thread, the stability of the sewing hooking thread can be ensured, so that the occurrence of the bird nest is reduced. After the thread is cut, the sliding plate moves to the avoiding position to avoid the interference caused by the moving cutter below the needle plate.

Description

TECHNICAL FIELD

[0001] The present application relates to the sewing machine technical field, and particularly relates to a thread clamping and cutting device, and further relates to a sewing machine comprising the thread clamping and cutting device. BACKGROUND

[0002] In the sewing machine industry, measures for reducing the occurrence of bird nests are usually to grasp the thread in the starting stage and release the thread after sewing several stitches to ensure the stability of the starting thread hooking, thereby reducing the occurrence of bird nests.

[0003] The existing thread clamping device does not have a thread cutting function after clamping the thread, which can cause the residual thread after grasping the thread to be too long and affect the appearance of the stitches, and the thread is always grasped during sewing, and the thread needs to be retracted to the thread taking position when the thread is released.

[0004] Therefore, how to provide a thread clamping and cutting device to reduce the occurrence of bird nests while ensuring the sewing quality is a technical problem that needs to be solved by those skilled in the art. SUMMARY

[0005] An object of the present application is to provide a thread clamping and cutting device that can grasp the thread in the starting stage and cut the thread after sewing several stitches to ensure the stability of the starting thread hooking, thereby reducing the occurrence of bird nests, and another object is to provide a sewing machine comprising the thread clamping and cutting device.

[0006] To solve the above technical problems, the present application provides the following technical solutions:

[0007] A thread clamping and cutting device, comprising:

[0008] A mounting seat fixed to a sewing machine and located below a needle plate;

[0009] A sliding plate movably connected to the mounting seat;

[0010] A thread grasping plate installed on the sliding plate for clamping sewing thread;

[0011] A thread cutting plate installed on the sliding plate for cutting sewing thread;

[0012] A transmission plate connected with the thread grasping plate and the thread cutting plate;

[0013] A drive rod connected with the transmission plate for driving the transmission plate to move, wherein the drive rod drives the thread grasping plate, the thread cutting plate and the sliding plate to move in sequence in the process of moving from the first end to the second end of the stroke to realize the actions of clamping sewing thread, cutting sewing thread and moving the sliding plate from the initial position to the avoiding position in the movement direction of the drive rod, respectively.

[0014] Preferably, the driving rod drives the thread-cutting plate, the thread-grabbing plate and the sliding plate in sequence to reset the thread-cutting plate, loosen the cut sewing thread and return the sliding plate from the avoiding position to the initial position respectively during the movement of the driving rod from the second end to the first end of the stroke.

[0015] Preferably, the movement stroke of the transmission plate relative to the sliding plate comprises a front thread-clamping stroke and a rear thread-cutting stroke, the front thread-clamping stroke of the transmission plate only drives the thread-grabbing plate to move to the thread-grabbing position, and the rear thread-cutting stroke of the transmission plate only drives the thread-cutting plate to move to the thread-cutting position.

[0016] Preferably, the sewing machine further comprises:

[0017] a thread-cutting connecting plate movably connected to the sliding plate, the thread-cutting connecting plate being provided with a transmission groove and an avoiding groove;

[0018] the thread-grabbing plate being rotatably connected to the sliding plate, one end of the thread-grabbing plate being provided with a needle-passing hole and the other end being provided with a sliding pin;

[0019] the thread-cutting plate being rotatably connected to the sliding plate, one end of the thread-cutting plate being provided with a transmission pin connected to the transmission groove;

[0020] the transmission plate being provided with a sliding groove slidably connected to the sliding pin, the transmission plate being hinged to the driving rod, the transmission plate being provided with a first guide pin and a second guide pin on both sides of the hinging position of the transmission plate and the driving rod, the first guide pin being slidably connected to the avoiding groove;

[0021] the sliding plate being provided with a first guide groove slidably connected to the first guide pin and a second guide groove slidably connected to the second guide pin;

[0022] during the front thread-clamping stroke of the transmission plate, the thread-grabbing plate is driven to rotate relative to the sliding plate to clamp the sewing thread passing through the needle-passing hole between the thread-grabbing plate and the sliding plate;

[0023] during the rear thread-cutting stroke of the transmission plate, the thread-cutting connecting plate is first driven to move relative to the sliding plate, and then the thread-cutting plate is driven to rotate relative to the sliding plate through the transmission groove to cut the sewing thread clamped on the thread-grabbing plate;

[0024] the driving rod is used to drive the sliding plate to move from the initial position to the movement direction of the driving rod through the first guide pin and the second guide pin after the thread-cutting is completed.

[0025] Preferably, a locking member is further included for locking the position of the sliding plate relative to the base when the sliding plate is in the initial position or in the avoiding position.

[0026] Preferably, the locking member includes an elastic limiting member for being clamped with the mounting seat when the sliding plate is in the initial position or in the avoiding position.

[0027] Preferably, the elastic limiting member is fixed on the mounting seat, a front limiting portion is arranged at the front end of the elastic limiting member, a rear limiting portion is arranged at the rear end of the elastic limiting member, a limiting hole is arranged on the sliding plate, the limiting hole is clamped with the front limiting portion when the sliding plate is in the initial position, and the limiting hole is clamped with the rear limiting portion when the sliding plate is in the avoiding position.

[0028] Or the elastic limiting member is fixed on the mounting seat, a limiting portion is arranged on the elastic limiting member, a front limiting hole and a rear limiting hole are arranged on the sliding plate, the rear limiting hole is clamped with the limiting portion when the sliding plate is in the initial position, and the front limiting hole is clamped with the limiting portion when the sliding plate is in the avoiding position.

[0029] Or the elastic limiting member is fixed on the sliding plate, a front limiting portion is arranged at the front end of the elastic limiting member, a rear limiting portion is arranged at the rear end of the elastic limiting member, a limiting hole is arranged on the mounting seat, the limiting hole is clamped with the rear limiting portion when the sliding plate is in the initial position, and the limiting hole is clamped with the front limiting portion when the sliding plate is in the avoiding position.

[0030] Or the elastic limiting member is fixed on the sliding plate, a limiting portion is arranged on the elastic limiting member, a front limiting hole and a rear limiting hole are arranged on the mounting seat, the front limiting hole is clamped with the limiting portion when the sliding plate is in the initial position, and the rear limiting hole is clamped with the limiting portion when the sliding plate is in the avoiding position.

[0031] Preferably, the locking member includes a pin and a telescopic driving portion, a front clamping hole and a rear clamping hole are arranged on the sliding plate, the telescopic driving portion drives the pin to be clamped into the rear clamping hole when the sliding plate is in the initial position, and the telescopic driving portion drives the pin to be clamped into the front clamping hole when the sliding plate is in the avoiding position.

[0032] Preferably, a positioning pin is arranged on the sliding plate, the positioning pin is used for limiting the rotation angle of the line catching plate.

[0033] Preferably, a rotation limiting pin is further arranged on the sliding plate, and when the driving rod drives the transmission plate to contact the rotation limiting pin, the transmission plate rotates around the second guide pin under the limiting action of the rotation limiting pin as the driving rod continues to drive the transmission plate.

[0034] Preferably, the thread cutting plate is arranged above the thread clamping plate to cut the sewing thread above the thread clamping plate, or is arranged below the sliding plate to cut the sewing thread below the sliding plate.

[0035] Preferably, the thread clamping plate and the thread cutting plate are slidingly connected to the sliding plate, and the driving rod is used to drive the transmission plate to move and in turn drive the thread clamping plate to clamp the sewing thread and the thread cutting plate to cut the sewing thread.

[0036] A sewing machine comprising the thread clamping and cutting device.

[0037] Compared with the prior art, the technical scheme has the following advantages:

[0038] The thread clamping and cutting device and the sewing machine provided by the present application comprise a mounting seat, a sliding plate, a thread clamping plate, a thread cutting plate, a transmission plate and a driving rod. The mounting seat is fixed to the sewing machine and arranged below a needle plate. The sliding plate is movably connected to the mounting seat. The thread clamping plate is arranged on the sliding plate. The thread cutting plate is arranged on the sliding plate. The transmission plate is connected to the thread clamping plate and the thread cutting plate. The driving rod is connected to the transmission plate and used to drive the transmission plate to move. The driving rod drives the thread clamping plate, the thread cutting plate and the sliding plate to move in sequence in the process of moving from a first end to a second end of a stroke to respectively realize the actions of clamping the sewing thread, cutting the sewing thread and moving the sliding plate from an initial position to an avoiding position in the movement direction of the driving rod. When it is necessary to clamp the thread, the driving rod first drives the thread clamping plate to clamp the sewing thread. After the sewing machine sews several stitches, the driving rod drives the thread cutting plate to cut the sewing thread to ensure the stability of the hooking thread, thereby reducing the occurrence of bird nests. After the thread is cut, the driving rod drives the sliding plate to move from the initial position to the avoiding position to avoid the interference caused by the moving knife below the needle plate. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical scheme in the present application or the prior art, the accompanying drawings required to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are some embodiments of the present application, and other accompanying drawings can be obtained by those skilled in the art without any creative effort.

[0040] Figure 1 It is a structural schematic view of the thread clamping and cutting device.

[0041] Figure 2 The exploded view of the face thread clamping and cutting device;

[0042] Figure 3 The structural schematic view of the face thread clamping and cutting device in the thread grabbing state;

[0043] Figure 4 The structural schematic view of the face thread clamping and cutting device in the thread cutting state;

[0044] Figure 5 The structural schematic view of the sliding plate of the face thread clamping and cutting device in the avoiding position;

[0045] Figure 6 The exploded view of the partial structure of the face thread clamping and cutting device;

[0046] Figure 7 The structural schematic view of the thread grabbing plate;

[0047] Figure 8 The structural schematic view of the face thread clamping and cutting device applied to the sewing machine.

[0048] The reference signs are as follows:

[0049] 1 is the mounting seat;

[0050] 2 is the sliding plate, 21 is the limiting hole, 22 is the positioning pin, 23 is the first guide groove, 24 is the rotating limiting pin, 25 is the abutting surface, and 26 is the second guide groove;

[0051] 3 is the thread grabbing plate, 31 is the needle passing hole, 32 is the sliding pin, 33 is the blade edge, and 34 is the thread clamping surface;

[0052] 4 is the thread cutting plate, and 41 is the transmission pin;

[0053] 5 is the transmission plate, 51 is the sliding groove, 52 is the first guide pin, and 53 is the second guide pin;

[0054] 6 is the driving rod;

[0055] 7 is the elastic limiting part, 71 is the front limiting part, and 72 is the rear limiting part;

[0056] 8 is the thread cutting connecting plate, 81 is the transmission groove, and 82 is the avoiding groove;

[0057] 9 is the pressing plate, 10 is the blowing pipe, 11 is the limiting block, 12 is the machine rod, and 13 is the needle plate. DETAILED DESCRIPTION

[0058] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below with reference to the drawings.

[0059] In the following description, specific details are set forth in order to provide a thorough understanding of the application. However, the application can be practiced without the specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to obscure the application.

[0060] Please refer to Figures 1-8 , Figure 1 Figure 1 is a schematic view of the face thread clamping and cutting device; Figure 2 Figure 2 is an exploded view of the face thread clamping and cutting device; Figure 3 Figure 3 is a schematic view of the face thread clamping and cutting device in a thread clamping state; Figure 4 Figure 4 is a schematic view of the face thread clamping and cutting device in a thread cutting state; Figure 5 Figure 5 is a schematic view of the face thread clamping and cutting device in a sliding plate avoiding position; Figure 6 Figure 6 is an exploded view of part of the structure of the face thread clamping and cutting device; Figure 7 Figure 7 is a schematic view of the thread clamping plate; Figure 8 Figure 8 is a schematic view of the face thread clamping and cutting device applied to a sewing machine.

[0061] One specific embodiment of the present application provides a face thread clamping and cutting device, comprising a mounting seat 1, a sliding plate 2, a thread clamping plate 3, a thread cutting plate 4, a transmission plate 5 and a driving rod 6. The mounting seat 1 is fixed to a sewing machine and located below a needle plate 13. The sliding plate 2 is movably connected to the mounting seat 1. The thread clamping plate 3 and the thread cutting plate 4 are installed on the sliding plate 2, wherein the thread clamping plate 3 is used to clamp sewing face thread, and the thread cutting plate 4 is used to cut sewing face thread. The transmission plate 5 is connected to the thread clamping plate 3 and the thread cutting plate 4 respectively. The driving rod 6 is connected to the transmission plate 5. The driving rod 6 is used to drive the transmission plate 5 to move. In the process of the driving rod 6 moving from the first end to the second end of the stroke, the thread clamping plate 3, the thread cutting plate 4 and the sliding plate 2 are sequentially driven to move to respectively realize the actions of clamping sewing face thread, cutting sewing face thread and moving the sliding plate 2 from the initial position to the avoiding position in the movement direction of the driving rod 6. When it is needed to clamp sewing face thread, the driving rod 6 drives the transmission plate 5 to move, first driving the thread clamping plate 3 to perform thread clamping operation on the sewing face thread. After the sewing machine sews several stitches, the driving rod 6 drives the thread cutting plate 4 to perform thread cutting operation on the sewing face thread to ensure the stability of the starting stitch hooking thread, thereby reducing the occurrence of bird nests. After the thread cutting is completed, the driving rod 6 drives the sliding plate 2 to move relative to the mounting seat 1 to avoid interference caused by the moving knife below the needle plate 13.

[0062] In some embodiments, the driving rod 6 drives the thread clamping plate 3, the thread clamping plate 4 and the sliding plate 2 in sequence during the movement of the driving rod 6 from the second end to the first end of the stroke, so as to realize the reset of the thread clamping plate 4, the release of the cut sewing thread and the return of the sliding plate 2 from the avoiding position to the initial position. In addition to the thread clamping operation of the thread clamping plate 3, the thread cutting operation of the thread clamping plate 4 and the avoiding operation of the sliding plate 2, the driving rod 6 can also realize the reset of the thread clamping plate 3, the thread clamping plate 4 and the sliding plate 2, so as to facilitate the next thread clamping and thread cutting operation.

[0063] In some embodiments, the movement stroke of the transmission plate 5 relative to the sliding plate 2 includes a front thread clamping stroke and a rear thread cutting stroke. The front thread clamping stroke of the transmission plate 5 only drives the thread clamping plate 3 to move to the thread clamping position, and the rear thread cutting stroke of the transmission plate 5 only drives the thread clamping plate 4 to move to the thread cutting position. That is, the thread clamping plate 3 and the thread clamping plate 4 have a sequence of actions, which can avoid cutting the sewing thread while clamping the thread.

[0064] In some embodiments, the thread clamping and cutting device further comprises a thread clamping plate 8 movably connected to the sliding plate 2, the thread clamping plate 8 being provided with a transmission groove 81 and an avoiding groove 82, the thread clamping plate 3 being rotatably connected to the sliding plate 2, one end of the thread clamping plate 3 being provided with a needle passing hole 31 for the needle 12 of the sewing machine to pass through, and the other end being provided with a sliding pin 32, the thread clamping plate 4 being rotatably connected to the sliding plate 2, one end of the thread clamping plate 4 being provided with a transmission pin 41 connected to the transmission groove 81, the thread clamping plate 3 and the thread clamping plate 4 being preferably hinged to the sliding plate 2 by the same rotating shaft, the thread clamping plate 3 being preferably in a V-shaped structure, the needle passing hole 31 being located at one end of the V-shaped structure, the sliding pin 32 being located at the other end of the V-shaped structure, the middle part of the V-shaped structure being hinged to the sliding plate 2 by the rotating shaft, the transmission plate 5 being provided with a sliding groove 51 slidably connected with the sliding pin 32, the transmission plate 5 being hinged with the driving rod 6, the transmission plate 5 being provided with a first guide pin 52 and a second guide pin 53 on both sides of the hinging position of the driving rod 6 and the transmission plate 5, the first guide pin 52 being slidably connected in the avoiding groove 82; the sliding plate 2 is provided with a first guide groove 23 slidably connected with the first guide pin 52 and a second guide groove 26 slidably connected with the second guide pin 53, the guide grooves being divided into front and rear sections, the sliding plate 2 is further provided with a positioning pin 22 and a rotating limiting pin 24, in the front thread clamping stroke of the transmission plate 5, the thread clamping plate 3 is driven to rotate relative to the sliding plate 2, and the sewing thread passing through the needle passing hole 31 is clamped between the thread clamping plate 3 and the sliding plate 2; in the rear thread cutting stroke of the transmission plate 5, the thread clamping plate 8 is first driven to move relative to the sliding plate 2, and then the thread clamping plate 4 is driven to rotate relative to the sliding plate 2 through the transmission groove 81 to cut the sewing thread clamped on the thread clamping plate 3; the driving rod is used to drive the sliding plate 2 to move from the initial position to the movement direction of the driving rod 6 after the thread cutting is completed, in addition, the sliding plate 2 is further provided with a pressing plate 9, and the driving rod 6 and the thread clamping plate 8 can be prevented from being raised by the pressing plate 9.

[0065] In the initial state, such as Figure 1 As shown, the front side of the clearance groove 82 abuts against or is close to the first guide pin 52, and the rear section of the wire-cutting connecting plate 8 covers the rear section of the first guide groove 23, so that the first guide pin 52 does not contact the wire-cutting connecting plate 8 at the front section of the first guide groove 23. At the same time, during the process of the drive rod 6 returning to the initial state, the wire-cutting plate 4 can be reset by pushing the front side wall of the clearance notch 82 through the first guide pin 52. In the initial state, the wire-cutting part of the wire-cutting plate 4 is located on the side close to the positioning pin 22. After the drive rod 6 drives the transmission plate 5 to move the front section of the wire clamping stroke, it can drive the wire-gripping plate 3 to rotate relative to the rotating shaft. Figure 3 As shown, the end of the wire gripping plate 3 with the needle hole 31 moves toward the positioning pin 22. At this time, the friction force of the wire gripping plate 3 on the wire cutting plate 4 tends to make the wire cutting plate 4 move toward the positioning pin 22. The wire cutting plate 4 is blocked by the positioning pin 22 and does not move, thereby limiting the rotation angle of the wire gripping plate 3. After the wire gripping plate 3 rotates, the wire passing through the needle hole 31 is clamped between the wire gripping plate 3 and the sliding plate 2.

[0066] After the sewing machine has sewn a few stitches, such as three or four stitches, the drive rod 6 moves the transmission plate 5 to the rear end for the thread cutting stroke. Figure 4 As shown, since the wire gripping plate 3 rotates to abut against the positioning pin 22, the position of the sliding pin 32 remains fixed and becomes a rotation support point. During the process of the drive rod 6 driving the transmission plate 5 to move, when the side wall of the transmission plate 5 near the position of the second guide pin 53 contacts the rotation limit pin 24, as the drive rod 6 continues to drive the transmission plate 5, the transmission plate 5 rotates around the second guide pin 53 under the restriction of the rotation limit pin 24. During this period, the sliding pin 32 moves in the sliding groove 51. At the same time, the first transmission pin 41 drives the wire cutting connecting plate 8 to move relative to the sliding plate 2 through the clearance groove 82. And through the transmission groove 81 and the transmission pin 41, the wire cutting plate 4 is driven to rotate relative to the rotating shaft to cut the surface wire clamped on the wire gripping plate 3. At this time, due to the force of the side wall of the sliding groove 51 on the sliding pin 32, the wire gripping plate 3 always remains in the wire gripping position.

[0067] After the thread is cut, as follows Figure 5 As shown, the drive rod 6 drives the sliding plate 2 to move from the first end to the second end relative to the mounting base 1 to the retracted position via the first guide pin 52 and the second guide pin 53, so that the moving knife located below the needle plate 13 will not collide with the device when cutting the thread after sewing is completed.

[0068] In some embodiments of this application, a locking member is also included. When the sliding plate 2 is in the initial position or when the sliding plate 2 is in the avoidance position, the locking member can lock the position of the sliding plate 2 relative to the mounting base 1 to improve the stability of the wire gripping and cutting operations and the avoidance position.

[0069] In some embodiments of the present application, the locking member comprises an elastic limiting member 7, which is used to be clamped with the mounting base 1 when the sliding plate 2 is in the initial position or the retracted position, so as to ensure the stability during the cutting of the thread and after the retraction of the sliding plate 2.

[0070] In some embodiments, the elastic limiting member 7 is fixed on the mounting base 1, the front end of the elastic limiting member 7 is provided with a front limiting portion 71, the rear end is provided with a rear limiting portion 72, the sliding plate 2 is provided with a limiting hole 21, the limiting hole 21 is clamped with the front limiting portion 71 when the sliding plate 2 is in the initial position, the sliding plate 2 is in the initial position, the transmission plate 5 has moved and rotated, and the force transmitted to the elastic limiting member 7 through the sliding plate 2 is not enough to deform the elastic limiting member 7; as the driving rod 6 continues to drive the rearward movement of the transmission plate 5, the pulling force of the driving rod 6 will cause the front limiting portion 71 to deform and come out of the limiting hole 21, the sliding plate 2 moves rearward with the driving rod 6, and the limiting hole 21 is clamped with the rear limiting portion 72 when the sliding plate 2 is in the retracted position.

[0071] Or the elastic limiting member 7 is fixed on the mounting base 1, the elastic limiting member 7 is provided with a limiting portion, the sliding plate 2 is provided with a front limiting hole 21 and a rear limiting hole 21, the rear limiting hole 21 is clamped with the limiting portion when the sliding plate 2 is in the initial position, and the front limiting hole 21 is clamped with the limiting portion when the sliding plate 2 is in the retracted position;

[0072] Or the elastic limiting member 7 is fixed on the sliding plate 2, the front end of the elastic limiting member 7 is provided with a front limiting portion 71, the rear end is provided with a rear limiting portion 72, the mounting base 1 is provided with a limiting hole 21, the limiting hole 21 is clamped with the rear limiting portion 72 when the sliding plate 2 is in the initial position, and the limiting hole 21 is clamped with the front limiting portion 71 when the sliding plate 2 is in the retracted position;

[0073] Or the elastic limiting member 7 is fixed on the sliding plate 2, the elastic limiting member 7 is provided with a limiting portion, the mounting base 1 is provided with a front limiting hole 21 and a rear limiting hole 21, the front limiting hole 21 is clamped with the limiting portion when the sliding plate 2 is in the initial position, and the rear limiting hole 21 is clamped with the limiting portion when the sliding plate 2 is in the retracted position.

[0074] In some embodiments of the present application, the locking member comprises a pin and a telescopic driving portion, the telescopic driving portion is preferably an electromagnet or other driving portion that can control the movement of the pin, the sliding plate 2 is provided with a front clamping hole and a rear clamping hole, the telescopic driving portion drives the pin to be clamped into the rear clamping hole when the sliding plate 2 is in the initial position, so as to limit the initial position of the sliding plate 2 relative to the mounting base 1; the telescopic driving portion drives the pin to be clamped into the front clamping hole when the sliding plate 2 is in the avoiding position, so as to limit the avoiding position of the sliding plate 2 relative to the mounting base 1.

[0075] In addition to the elastic limiting piece 7, the catch pin and the telescopic driving part, the sliding plate 2 can be limited in other ways, which can be selected according to actual conditions.

[0076] In some embodiments, as shown in Figure 6 and Figure 7 the upper surface of the thread passing hole of the thread catching plate 3 is provided with a blade 33 for cooperating with the thread cutting plate 4 to cut the thread, and the lower surface of the needle passing hole 31 of the thread catching plate 3 is provided with a thread clamping surface 34 for clamping the thread, and the sliding plate 2 is provided with an abutting surface 25 for cooperating with the thread clamping surface 34 to clamp the thread. When the thread is clamped, the thread cutting plate 4 does not contact the blade 33, so as to avoid cutting the thread when the thread is clamped.

[0077] In some embodiments, as shown in Figures 1-5 the thread cutting plate 4 is located above the thread catching plate 3 to cut the sewing thread above the thread catching plate 3. Alternatively, the thread cutting plate 4 is located below the sliding plate 2 to cut the sewing thread from below the sliding plate 2.

[0078] In some embodiments, the mounting seat 1 is provided with a limiting block 11 for limiting the stroke of the sliding plate 2, as shown in Figure 2 the rear end of the sliding plate 2 is slidingly connected between the two limiting blocks 11 arranged in front and back of the mounting seat 1, and the middle part of the mounting seat 1 is provided with an opening slot opening backward, and the driving rod 6 can move forward and backward in the opening slot.

[0079] In some embodiments, the thread catching plate 3 and the thread cutting plate 4 are slidingly connected to the sliding plate 2, and the driving rod 6 is used to drive the transmission plate 5 to move, and in turn drive the thread catching plate 3 to clamp the sewing thread and the thread cutting plate 4 to cut the sewing thread. For example, the driving rod 6 first drives the transmission plate 5 to move a distance, during which the thread catching plate 3 is synchronously moved to clamp the sewing thread on the mounting seat 1, and then the driving rod 6 continues to move a distance to drive the thread cutting plate 4 to move to cut the sewing thread clamped by the thread catching plate 3.

[0080] One embodiment of the present application also provides a sewing machine comprising the thread clamping and cutting device provided by any of the above embodiments. The driving rod 6 is driven by a driving motor or other driving member, and the driving member is electrically connected with the controller of the sewing machine. The thread clamping and cutting device is located at the thread loosening position, and the thread head is located near the connection between the base and the shuttle bed of the sewing machine. The sewing machine is provided with a suction pipe 10 opening towards the thread loosening position, which is connected with a negative pressure source for sucking the thread head. The negative pressure pipe is provided with an electromagnetic valve electrically connected with the controller.

[0081] In summary, the face thread clamping and cutting device provided by the application completes the actions of thread catching, thread cutting, sliding plate 2 sliding and avoiding, thread catching plate 3 resetting and sending thread head, thread cutting plate 4 resetting, and sliding plate 2 resetting in one reciprocating cycle through the cooperation between sliding plate 2, thread catching plate 3, thread cutting plate 4, transmission plate 5, thread cutting connecting plate 8, and elastic limiting part 7; the face thread clamping and cutting device has the characteristics that the needle hole passing hole 31 of the thread catching plate 3 in the initial state can extend to below the needle plate hole, and the thread loosening position is far away from below the needle plate hole, so that the thread catching position and the thread loosening position are separated, the position of the thread loosening head can be adjusted to a position with relatively large space through adjustment of the total stroke, and since the thread catching structure extends relative to the mounting base 1, the face thread clamping and cutting device is more suitable for a sewing machine with relatively small space below the needle plate 13; in each positioning state in the initial state, the thread catching state, the thread cutting state, and the thread loosening head state, the driving rod 6 is not subjected to additional force and does not increase the load of the driving part; the needle hole passing hole 31 arranged on the thread catching plate 3 enables the face thread on the needle 12 to always remain in the needle hole passing hole 31 during the thread catching process, so that the face thread can be stably caught; the thread cutting position is close to the needle plate hole, so that the thread head remaining on the fabric after cutting is relatively short and is easily wrapped by subsequent stitches, and even if the thread head cannot be wrapped, the beauty of the stitches is not affected.

[0082] It should be noted that the relational terms herein such as first and second and the like are used solely to distinguish one from another entity or action without necessarily requiring or implying that there is any such relationship or order between such entities or actions.

[0083] The above description of disclosed embodiments allows a person skilled in the art to implement or use the application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A thread clamping and cutting device, characterized in that, include: Mounting base, fixed on the sewing machine and located below the needle plate; A sliding plate is movably connected to the mounting base; A thread gripper, mounted on the sliding plate, is used to hold the sewing thread. A thread cutter, installed on the sliding plate, is used to cut the sewing thread; The transmission plate is connected to the wire gripping plate and the wire cutting plate respectively; A drive rod, connected to the transmission plate, is used to drive the transmission plate to move. During the movement of the drive rod from the first end to the second end of its stroke, it sequentially drives the thread gripping plate, the thread cutting plate, and the sliding plate to move, respectively, to achieve the actions of clamping the sewing thread, cutting the sewing thread, and the sliding plate moving from the initial position to the direction of the drive rod to the avoidance position. The movement stroke of the transmission plate relative to the sliding plate includes a front wire clamping stroke and a rear wire cutting stroke. The front wire clamping stroke of the transmission plate only drives the wire gripping plate to the wire gripping position, and the rear wire cutting stroke of the transmission plate only drives the wire cutting plate to the wire cutting position. The thread clamping and cutting device also includes: A wire-cutting connecting plate is movably connected to the sliding plate, and the wire-cutting connecting plate is provided with a transmission groove and a clearance groove; The wire gripping plate is rotatably connected to the sliding plate. One end of the wire gripping plate is provided with a needle hole, and the other end is provided with a sliding pin. The wire-cutting plate is rotatably connected to the sliding plate, and one end of the wire-cutting plate is provided with a transmission pin connected to the transmission groove; The transmission plate is provided with a sliding groove that is slidably connected to the sliding pin. The transmission plate is hinged to the drive rod. The transmission plate is provided with a first guide pin and a second guide pin on both sides of the hinge point between the drive rod and the transmission plate. The first guide pin is slidably connected in the clearance groove. The sliding plate is provided with a first guide groove that is slidably connected to the first guide pin and a second guide groove that is slidably connected to the second guide pin; During the front section of the wire clamping stroke of the transmission plate, the wire gripping plate is driven to rotate relative to the sliding plate, thereby clamping the thread passing through the needle hole between the wire gripping plate and the sliding plate. During the rear thread-cutting stroke of the transmission plate, the thread-cutting connecting plate is first moved relative to the sliding plate, and then the thread-cutting plate is rotated relative to the sliding plate through the transmission groove to cut the sewing thread clamped on the thread-grabbing plate. The drive rod is used to drive the sliding plate from its initial position toward the direction of the drive rod movement via the first guide pin and the second guide pin after the wire is cut.

2. The thread clamping and cutting device according to claim 1, characterized in that, As the drive rod moves from the second end of its stroke to the first end, it sequentially drives the thread cutter, the thread gripper, and the sliding plate to move, thereby respectively achieving the actions of resetting the thread cutter, releasing the cut sewing thread, and the sliding plate returning from the avoidance position to the initial position.

3. The thread clamping and cutting device according to claim 1 or 2, characterized in that, It also includes a locking element for locking the position of the sliding plate relative to the base when the sliding plate is in the initial position or when the sliding plate is in the avoidance position.

4. The thread clamping and cutting device according to claim 3, characterized in that, The locking element includes an elastic limiting element, which is used to engage with the mounting base when the sliding plate is in the initial position or the avoidance position.

5. The thread clamping and cutting device according to claim 4, characterized in that, The elastic limiting member is fixed on the mounting base. The front end of the elastic limiting member is provided with a front limiting part and the rear end is provided with a rear limiting part. The sliding plate is provided with a limiting hole. When the sliding plate is in the initial position, the limiting hole is engaged with the front limiting part. When the sliding plate is in the retracted position, the limiting hole is engaged with the rear limiting part. Alternatively, the elastic limiting member is fixed on the mounting base, the elastic limiting member is provided with a limiting part, the sliding plate is provided with a front limiting hole and a rear limiting hole, when the sliding plate is in the initial position, the rear limiting hole is engaged with the limiting part, and when the sliding plate is in the retracted position, the front limiting hole is engaged with the limiting part. Alternatively, the elastic limiting member can be fixed on the sliding plate. The front end of the elastic limiting member is provided with a front limiting part, and the rear end is provided with a rear limiting part. The mounting base is provided with a limiting hole. When the sliding plate is in the initial position, the limiting hole is engaged with the rear limiting part. When the sliding plate is in the retracted position, the limiting hole is engaged with the front limiting part. Alternatively, the elastic limiting member can be fixed to the sliding plate. The elastic limiting member has a limiting part, and the mounting base has a front limiting hole and a rear limiting hole. When the sliding plate is in the initial position, the front limiting hole engages with the limiting part. When the sliding plate is in the retracted position, the rear limiting hole engages with the limiting part.

6. The thread clamping and cutting device according to claim 3, characterized in that, The locking component includes a locking pin and a telescopic drive unit. The sliding plate is provided with a front locking hole and a rear locking hole. When the sliding plate is in the initial position, the telescopic drive unit drives the locking pin to engage with the rear locking hole. When the sliding plate is in the clearance position, the telescopic drive unit drives the locking pin to engage with the front locking hole.

7. The thread clamping and cutting device according to claim 1, characterized in that, The sliding plate is provided with a positioning pin, which is used to limit the rotation angle of the wire gripping plate.

8. The thread clamping and cutting device according to claim 1, characterized in that, The sliding plate is also provided with a rotation limit pin. When the driving rod drives the transmission plate to contact the rotation limit pin, as the driving rod continues to drive the transmission plate, the transmission plate rotates around the second guide pin under the restriction of the rotation limit pin.

9. The thread clamping and cutting device according to claim 1, characterized in that, The thread-cutting plate is located above the thread-grabbing plate to cut the sewing thread above the thread-grabbing plate; or it is located below the sliding plate to cut the sewing thread below the sliding plate.

10. The thread clamping and cutting device according to claim 1, characterized in that, The thread gripping plate and the thread cutting plate are slidably connected to the sliding plate. The driving rod is used to drive the transmission plate to move, and in turn, drive the thread gripping plate to clamp the sewing thread and the thread cutting plate to cut the sewing thread.

11. A sewing machine, characterized in that, Includes the thread clamping and cutting device according to any one of claims 1 to 10.

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