Thread shifting mechanism of sewing machine

Abstract

The utility model provides a thread shifting mechanism of a sewing machine, and belongs to the technical field of sewing machines. The problem that an existing wire shifting mechanism is insufficient in working reliability is solved. According to the thread shifting mechanism of the sewing machine, the sewing machine comprises a base and a rotating shuttle arranged in the base, the thread shifting mechanism comprises a thread shifting rod and a strip-plate-shaped thread shifting base located on the side portion of the rotating shuttle, the thread shifting rod is arranged on the thread shifting base, and the end portion of the thread shifting rod can stretch into the upper portion of the rotating shuttle to do circumferential circulating motion. The end, away from the rotating shuttle, of the thread shifting base is rotationally arranged on the base, a driving piece is further arranged on the base, and the driving piece can drive the other end of the thread shifting base to horizontally swing forwards so that the end of the thread shifting rod can be away from the rotating shuttle. The thread shifting rod can be effectively prevented from colliding with the thread trimming movable cutter, so that the reliability of sewing work is remarkably improved.

Description

A thread-picking mechanism for a sewing machine Technical Field

[0001] This utility model belongs to the field of sewing machine technology and relates to a thread-picking mechanism for a sewing machine. Background Technology

[0002] A sewing machine is a device that uses one or more threads to create stitches on fabric, allowing two or more layers of fabric to be sewn together. When traditional sewing machines sew patterns, the fabric moves horizontally in different directions with the feed mechanism, resulting in some stitches being forward stitches (301 stitch) and others being reverse stitches (319 stitch). Since forward stitches generally ensure aesthetics and consistency, they are used exclusively for sewing high-end garments and leather goods where high quality is required. Therefore, to maintain the product's appearance, reverse stitches must be avoided.

[0003] To address this technical problem, existing technologies utilize a thread-shifting lever to move the bottom thread between the rotary hook and the needle plate, switching stitches to prevent reverse stitches during sewing. For example, a sewing machine and sewing method disclosed in patent literature (application number: 202510475452.3) includes a base, a needle plate, a bottom shuttle, a transmission rod, and a thread-shifting lever. The transmission rod is located on the side of the bottom shuttle and movably connected to the base. One end of the transmission rod near the bottom shuttle is fixedly connected to one end of the thread-shifting lever, and the other end of the transmission rod is connected to a thread-shifting drive component. Driven by the thread-shifting drive component, the transmission rod can reciprocate axially and oscillate, causing the other end of the thread-shifting lever to perform a circumferential cyclic motion and be positioned between the needle drop hole and the bottom shuttle. While this sewing machine can prevent reverse stitches during sewing, it still has the following shortcomings: During its movement, the other end of the thread-picking lever always passes between the needle hole and the bobbin. When thread cutting is required, such as cutting the starting thread, the end thread, or the bobbin thread, the thread-cutting blade needs to move between the needle hole and the bobbin to perform the cutting operation. To avoid collision and interference between the thread-cutting blade and the thread-picking lever, the motor needs to be controlled to rotate to a specific angle and then stop, so that the thread-picking lever moves to a position where it will not interfere with the thread-cutting blade. However, because the needle continuously performs a high-speed needle-down motion, the thread-cutting blade needs to move quickly under the needle to cut the thread. Therefore, the time available for the motor to adjust the position of the thread-picking lever is limited. The motor must receive the control signal within a very short time and quickly adjust the rotation angle to a specific position to achieve rapid positioning of the thread-picking lever; otherwise, interference with the thread-cutting blade cannot be avoided. Obviously, in this design, the motor needs to both drive the thread-picking lever to perform the thread-picking action and precisely control the thread-picking lever to a specific position during thread cutting. Therefore, it requires a complex control algorithm, which is difficult to implement. The motor may have mechanical errors, parameter drift in the control system, or external interference, which may cause the actual rotation angle to deviate from the target angle. As a result, the thread-picking lever may not be in the safe zone and may collide with the thread-cutting blade. Therefore, the thread-picking mechanism of this sewing machine has the defect of insufficient reliability. Summary of the Invention

[0004] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a thread-picking mechanism for sewing machines. This invention solves the problem of insufficient reliability in existing thread-picking mechanisms.

[0005] The objective of this utility model can be achieved through the following technical solution: a thread-picking mechanism for a sewing machine, the sewing machine including a base and a rotary hook disposed within the base, the thread-picking mechanism including a thread-picking rod and a strip-shaped thread-picking seat located on the side of the rotary hook, the thread-picking rod being disposed on the thread-picking seat and the end of the thread-picking rod being able to extend into the top of the rotary hook to perform circumferential cyclic movement, characterized in that the end of the thread-picking seat away from the rotary hook is rotatably disposed on the base, the base also being provided with a driving member, the driving member being able to drive the other end of the thread-picking seat to swing forward horizontally so that the end of the thread-picking rod moves away from the rotary hook.

[0006] In this thread-picking mechanism, the thread-picking seat is rotatably mounted on the base, rather than being fixedly connected in the traditional way. This allows the sewing machine to easily rotate the thread-picking seat forward by a specific angle using a drive mechanism. This moves the thread-picking lever, mounted on the seat, forward into a more open space in front of the rotary hook, avoiding the movement path of the thread-cutting blades on the outer edge of the hook, thus preventing interference between the blades and the lever. Furthermore, the needle plate is located above the rotary hook, and the space between the hook and the needle plate is very small. The other end of the thread-picking seat swings forward horizontally, causing the end of the thread-picking lever to also move forward horizontally away from the rotary hook, ensuring that it does not collide with the hook or needle plate during its movement. Compared to existing designs, this thread-picking mechanism, during thread cutting, only requires a simple rotation control of the originally stationary thread-picking seat by a drive mechanism to ensure that the thread-picking lever stably and accurately reaches the predetermined avoidance position. During this process, the motor driving the thread-picking lever can keep running continuously, thus reducing the need for frequent motor starts and stops and complex angle control, greatly reducing the difficulty of control, and effectively preventing the thread-picking lever from colliding with the thread-cutting blade, thereby significantly improving the reliability of sewing work.

[0007] When the sewing machine is working, when it is sewing in reverse, the end of the thread lever extends above the rotary hook and makes a circumferential circular motion. This pushes the bobbin thread between the rotary hook and the needle plate, causing part of the bobbin thread to cross the axis of the needle. After the needle moves downward, it brings the top thread under the needle plate and then detaches from the bobbin thread. This ensures that during the tightening process as the needle moves upward, the bobbin thread and the top thread on the fabric are on the same side of the top thread on the needle, thus avoiding the generation of reverse stitches.

[0008] In the aforementioned thread-picking mechanism of the sewing machine, the mechanism further includes a vertically arranged drive shaft. The end of the thread-picking seat away from the rotary hook has a mounting hole. A bearing with an outer ring tightly fitted into the mounting hole is installed within the mounting hole. A bushing is fixedly fitted onto the drive shaft. The bushing has a convex cross-section, with a supporting step formed on its outer peripheral wall. The inner ring of the bearing is tightly fitted into the outer peripheral wall of the bushing, and the lower end face of the bearing's inner ring abuts against the supporting step. In this structure, the thread-picking seat is rotatably mounted via the bearing, bushing, and drive shaft. The outer ring of the bearing is tightly fitted into the mounting hole of the thread-picking seat, and the inner ring is tightly fitted into the outer peripheral wall of the bushing, forming a stable rotating connection. This reduces radial and axial wobble of the thread-picking seat during rotation, ensuring the accuracy of the thread-picking lever's movement trajectory. Furthermore, the bushing has a "convex" shaped longitudinal section, and the supporting steps on its outer peripheral wall abut against the lower end face of the bearing inner ring, providing stable axial positioning for the bearing and limiting the movement of the wire guide seat along the transmission shaft. This ensures that the wire guide seat can maintain a stable position under rotation and stress, making the wire guide mechanism stable and reliable in operation.

[0009] In the thread-picking mechanism of the sewing machine described above, the driving component is a cylinder fixedly connected to the base and located behind the thread-picking seat. The piston rod of the cylinder is horizontally positioned and its end is hinged to the thread-picking seat. When thread cutting is required, the sewing machine control system controls the cylinder to extend, causing the piston rod to swing forward at a specific angle. This cylinder-driven mechanism allows the thread-picking seat to rotate quickly and precisely, ensuring the thread-picking lever reliably avoids the thread-cutting blade, meeting the high-speed thread-cutting rhythm of the sewing machine, and preventing interference between the thread-cutting blade and the thread-picking lever due to driving delays.

[0010] In the thread-picking mechanism of the sewing machine described above, the driving component includes a cam horizontally positioned behind the thread-picking seat and a motor for driving the cam to rotate. A tension spring is provided between the thread-picking seat and the base, and under the action of the tension spring, the rear side of the thread-picking seat always abuts against the outer circumferential surface of the cam. During normal sewing, the motor remains in standby mode. When thread cutting is required, the sewing machine control system controls the motor to rotate by a preset angle, causing the cam to rotate by the corresponding angle. The tip of the cam pushes the thread-picking seat forward. Because this method only requires the motor, which is originally in standby mode, to rotate by a specific angle, it can also make the thread-picking seat rotate quickly and accurately, allowing the thread-picking lever to reliably avoid the thread-cutting blade.

[0011] In the thread-picking mechanism of the sewing machine described above, a guide seat capable of horizontal rotation is provided on the upper side of the thread-picking base. The thread-picking lever is slidably connected to the guide seat (14) along the axial direction. The thread-picking mechanism also includes a second motor fixedly connected to the base. The lower end of the transmission shaft is coaxially fixedly connected to the rotating shaft of the second motor. A thread-picking wheel is fixedly connected to the upper end of the transmission shaft. The end of the thread-picking lever away from the rotary hook is hinged to the eccentric position of the thread-picking wheel. When the thread-picking wheel rotates, it can drive the thread-picking lever to move back and forth axially and swing at the same time, so that the end of the thread-picking lever can perform circumferential circular motion. By setting a second motor separately to drive the thread-picking lever to perform the thread-picking action, the second motor can continue to run when the sewing machine needs to cut the thread, reducing mechanical wear caused by frequent start-stop and extending the service life of the second motor.

[0012] In the thread-picking mechanism of the sewing machine described above, the sewing machine further includes a main shaft housed within the base. The upper surface of the thread-picking seat is provided with a horizontally rotatable guide seat. The thread-picking lever is slidably connected to the guide seat along the axial direction. The thread-picking mechanism also includes a drive shaft parallel to the main shaft. The main shaft can drive the drive shaft to rotate synchronously. The front end of the drive shaft is connected to the lower end of the transmission shaft via a bevel gear pair. A thread-picking wheel is fixedly connected to the upper end of the transmission shaft. The end of the thread-picking lever away from the rotary hook is hinged to the eccentric position of the thread-picking wheel. The upper surface of the thread-picking seat is provided with a horizontally rotatable guide seat, and the thread-picking lever is slidably connected to the guide seat along the axial direction. The main shaft is the most important power shaft of the sewing machine, responsible for transmitting power to other moving parts of the sewing machine, such as the needle bar and bobbin, thereby completing the sewing work. The main shaft drives the drive shaft to rotate synchronously, which in turn drives the transmission shaft to rotate via the bevel gear pair, ultimately driving the thread-picking lever to perform the thread-picking action. In this thread-picking mechanism, the thread-picking lever can continuously move during the thread-cutting process of the sewing machine. This allows the thread-cutting mechanism to directly use the main shaft of the sewing machine to drive the thread-picking lever, avoiding the increased cost caused by setting up an additional motor to drive the thread-picking lever.

[0013] In the thread-picking mechanism of the sewing machine described above, the base has a vertically arranged mounting wall located behind the thread-picking seat. The first cylinder is located behind the mounting wall, and its piston rod passes through the mounting wall and is hinged to the thread-picking seat. This structure places the first cylinder behind the mounting wall, preventing it from occupying the working space of the thread-picking seat and avoiding spatial interference between the first cylinder and components such as the thread-picking lever and the thread-cutting blade, resulting in a more rational spatial design.

[0014] In the thread-picking mechanism of the sewing machine described above, the front end of the main shaft and the drive shaft are connected by a belt drive. This structure allows the main shaft to drive the drive shaft to rotate synchronously, and the belt drive has the advantages of low cost and easy maintenance.

[0015] The objective of this utility model can also be achieved through the following technical solutions: a thread-picking mechanism for a sewing machine, the sewing machine including a base and a rotary hook disposed within the base, the thread-picking mechanism including a thread-picking rod and a strip-shaped thread-picking seat located on the side of the rotary hook, the thread-picking rod being disposed on the thread-picking seat and the end of the thread-picking rod being able to extend into the upper part of the rotary hook to perform circumferential cyclic movement, characterized in that the thread-picking seat is slidably disposed on the base in a horizontal direction, the base also being provided with a driving member, the driving member being able to drive the thread-picking seat to translate so that the end of the thread-picking rod moves away from the rotary hook.

[0016] In this thread-picking mechanism, the thread-picking seat slides horizontally on the base instead of being fixedly connected as in traditional designs. This allows the thread-picking seat to be moved horizontally a specific distance by a drive mechanism when the sewing machine needs to cut the thread. This causes the thread-picking lever on the seat to move away from the rotary hook, avoiding the movement path of the thread-cutting blades around the hook, thus preventing interference between the blades. Furthermore, the space between the rotary hook and the needle plate is very small, and the translation of the thread-picking seat causes the end of the thread-picking lever to move forward horizontally away from the rotary hook, ensuring that it does not collide with the hook or needle plate during its movement. Compared to existing designs, this thread-picking mechanism only requires simple translation control of the originally stationary thread-picking seat by a drive mechanism during thread cutting to ensure that the thread-picking lever stably and accurately reaches the predetermined avoidance position. During this process, the motor driving the thread-picking lever can keep running continuously, thus reducing the need for frequent motor starts and stops and complex angle control, greatly reducing the difficulty of control, and effectively preventing the thread-picking lever from colliding with the thread-cutting blade, thereby significantly improving the reliability of sewing work.

[0017] In the thread-picking mechanism of the sewing machine described above, the base has a horizontally arranged slide rail in the front-to-back direction. The thread-picking seat is slidably connected to the slide rail. The driving component is a second cylinder fixedly connected to the base and located behind the thread-picking seat. The piston rod of the second cylinder is horizontally arranged in the front-to-back direction and its end is fixedly connected to the thread-picking seat. The thread-picking seat is fixedly connected to the slide rail on the base to ensure the stability of the thread-picking seat's front-to-back translation. When thread cutting is required, the sewing machine control system only needs to control the second cylinder to extend its piston rod, which will drive the thread-picking seat to move forward a specific stroke. The cylinder-driven method allows the thread-picking seat to rotate quickly and accurately, ensuring that the thread-picking lever reliably avoids the thread-cutting blade, meeting the high-speed thread-cutting rhythm of the sewing machine, and avoiding interference between the thread-cutting blade and the thread-picking lever due to drive delay.

[0018] Compared with existing technologies, the thread-picking mechanism of this sewing machine has the following advantages: During the thread-cutting process, this thread-picking mechanism only requires simple rotation or translation control of the originally stationary thread-picking seat by the drive component to ensure that the thread-picking lever stably and accurately reaches the predetermined avoidance position. During this process, the motor driving the thread-picking lever can continue to run, ensuring continuous movement of the thread-picking lever. This reduces frequent motor starts and stops and complex angle control steps, greatly reducing control difficulty and effectively preventing collisions between the thread-picking lever and the thread-cutting blade, thus significantly improving the reliability of the sewing operation. Attached Figure Description

[0019] Figure 1 is a partial structural schematic diagram of Embodiment 1 of this sewing machine.

[0020] Figure 2 is a three-dimensional structural schematic diagram of the first embodiment of the wire-pulling mechanism.

[0021] Figure 3 is a cross-sectional view of the wire-picking mechanism along the axis of the wire-picking rod.

[0022] Figure 4 is a diagram of the method at point A in Figure 3.

[0023] Figure 5 is an exploded view of the wire drawer, bearing, and bushing.

[0024] Figure 6 is a top view of Embodiment 1 of this wire-picking mechanism.

[0025] Figure 7 is a structural schematic diagram of Embodiment 2 of this wire-pulling mechanism.

[0026] Figure 8 is a structural schematic diagram of Embodiment 3 of this wire-picking mechanism.

[0027] Figure 9 is a structural schematic diagram of Embodiment 4 of this wire-picking mechanism.

[0028] In the diagram, 1. Base; 1a. Mounting wall; 1b. Slide rail; 2. Rotary hook; 3. Thread pick lever; 4. Thread pick seat; 41. Mounting hole; 5. Cylinder 1; 6. Drive shaft; 7. Bearing; 8. Bushing; 81. Support step; 9. Cam; 10. Motor 1; 11. Tension spring; 12. Motor 2; 13. Thread pick wheel; 14. Guide seat; 15. Main shaft; 16. Drive shaft; 17. Bevel gear pair; 18. Belt; 19. Cylinder 2; 20. Thread cutting blade; 21. Needle plate. Detailed Implementation

[0029] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0030] Example 1

[0031] As shown in Figures 1 and 2, the sewing machine includes a base 1 and a rotary hook 2 located below the needle plate 21 within the base 1. The thread-picking mechanism includes a thread-picking lever 3 and a strip-shaped thread-picking seat 4 located on the side of the rotary hook 2. The thread-picking lever 3 is mounted on the thread-picking seat 4, and the end of the thread-picking lever 3 can extend into the top of the rotary hook 2 to perform circumferential cyclic movement. The end of the thread-picking seat 4 away from the rotary hook 2 is rotatably mounted on the base 1. The base 1 is also provided with a driving component, which can drive the free end of the thread-picking seat 4 to swing forward horizontally, causing the end of the thread-picking lever 3 to move away from the rotary hook 2.

[0032] Specifically, as shown in Figure 2, the driving component is a cylinder 5 fixedly connected to the base 1 and located behind the thread guide 4. The piston rod of the cylinder 5 is horizontally positioned, and its end is hinged to the thread guide 4. When thread cutting is required, the sewing machine control system controls the cylinder 5 to extend, causing the piston rod of the cylinder 5 to swing forward at a specific angle. This causes the thread guide lever 3, which is mounted on the thread guide 4, to move forward into a more open space in front of the rotary hook 2, avoiding the movement path of the thread-cutting blade 20 on the periphery of the rotary hook 2, thus preventing interference between the thread-cutting blade 20 and the thread guide lever 3.

[0033] As shown in Figures 1 and 2, this sewing machine also includes a main shaft 15 housed within the base 1. The thread-picking mechanism also includes a drive shaft 16 parallel to the main shaft 15. The front ends of the main shaft 15 and the drive shaft 16 are connected via a belt 18, enabling the main shaft 15 to drive the drive shaft 16 to rotate synchronously. The front end of the drive shaft 16 is connected to the lower end of the transmission shaft 6 via a bevel gear pair 17. A thread-picking wheel 13 is fixedly connected to the upper end of the transmission shaft 6. The end of the thread-picking lever 3 away from the rotary hook 2 is hinged to the eccentric position of the thread-picking wheel 13. A horizontally rotatable guide seat 14 is provided on the upper side of the thread-picking base 4, and the thread-picking lever 3 is slidably connected to the guide seat 14 along its axial direction. In this thread-picking mechanism, the thread-picking lever 3 can continuously move during the thread-cutting process of the sewing machine. This allows the thread-cutting mechanism to directly utilize the main shaft 15 of the sewing machine to drive the thread-picking lever 3, avoiding the increased cost associated with additionally setting up a motor to drive the thread-picking lever 3.

[0034] As shown in Figures 3 to 5, the wire-picking mechanism also includes a vertically arranged drive shaft 6. One end of the wire-picking base 4 has a mounting hole 41. A bearing 7 with an outer ring tightly fitted into the mounting hole 41 is installed inside the mounting hole 41. A bushing 8 is fixedly sleeved on the drive shaft 6. The longitudinal section of the bushing 8 is convex, and a supporting step 81 is formed on its outer peripheral wall. The inner ring of the bearing 7 is tightly fitted into the outer peripheral wall of the bushing 8, and the lower end face of the inner ring of the bearing 7 abuts against the supporting step 81. In this structure, the wire-picking base 4 is rotatably mounted through the cooperation of the bearing 7, the bushing 8, and the drive shaft 6.

[0035] As shown in Figures 2 and 6, the base 1 has a vertically arranged mounting wall 1a located behind the cable tray 4, and the cylinder 5 is located behind the mounting wall 1a and the piston rod of the cylinder 5 passes through the mounting wall 1a and is hinged to the cable tray 4.

[0036] Example 2

[0037] This embodiment is basically the same in structure and principle as Embodiment 1, except that, as shown in Figure 7, the driving component includes a cam 9 horizontally positioned behind the thread guide 4 and a motor 10 for rotating the cam 9. A tension spring 11 is provided between the thread guide 4 and the base 1. Under the action of the tension spring 11, the rear side of the thread guide 4 always abuts against the outer circumferential surface of the cam 9. During normal sewing, the motor 10 remains in standby mode. When thread cutting is required, the sewing machine control system controls the motor 10 to rotate at a preset angle, causing the cam 9 to rotate at the corresponding angle. The tip of the cam 9 pushes the thread guide 4 forward. Because this method only requires the motor 10, which is originally in standby mode, to rotate at a specific angle, the thread guide 4 can also rotate quickly and accurately, allowing the thread guide lever 3 to reliably avoid the thread cutting blade 20.

[0038] Example 3

[0039] This embodiment is basically the same in structure and principle as Embodiment 1, except that the driving method of the thread-picking lever 3 is different. Specifically, as shown in Figure 8, the thread-picking mechanism also includes a second motor 12 fixedly connected to the base 1. The lower end of the transmission shaft 6 is coaxially fixedly connected to the rotating shaft of the second motor 12, and the upper end of the transmission shaft 6 is fixedly connected to a thread-picking wheel 13. The end of the thread-picking lever 3 away from the rotary hook 2 is hinged to the eccentric position of the thread-picking wheel 13. A guide seat 14 that can rotate horizontally is provided on the upper side of the thread-picking base 4, and the thread-picking lever 3 is slidably connected to the guide seat 14 along the axial direction. When the thread-picking wheel 13 rotates, it can drive the thread-picking lever 3 to move back and forth axially and swing at the same time, so that the end of the thread-picking lever 3 performs circumferential circular motion. By setting the second motor 12 separately to drive the thread-picking lever 3 to perform the thread-picking action, the second motor 12 can continue to run when the sewing machine needs to cut the thread, reducing mechanical wear caused by frequent start and stop and extending the service life of the second motor 12.

[0040] Example 4

[0041] This embodiment is basically the same as the third embodiment in terms of structure and principle. The difference is as follows: As shown in Figure 9, in the thread-picking mechanism of this sewing machine, the sewing machine includes a base 1 and a rotary hook 2 disposed in the base 1. The thread-picking mechanism includes a thread-picking rod 3 and a strip-shaped thread-picking seat 4 located on the side of the rotary hook 2. The thread-picking rod 3 is disposed on the thread-picking seat 4 and the end of the thread-picking rod 3 can extend into the top of the rotary hook 2 to make circumferential cyclic movement. The thread-picking seat 4 is slidably disposed on the base 1 in the horizontal direction. The base 1 is also provided with a driving component. The driving component can drive the thread-picking seat 4 to translate so that the end of the thread-picking rod 3 moves away from the rotary hook 2.

[0042] Specifically, the base 1 has a horizontally arranged slide rail 1b along the front-to-back direction. The thread-picking seat 4 is slidably connected to the slide rail 1b. The driving component is a cylinder 19 fixedly connected to the base 1 and located behind the thread-picking seat 4. The piston rod of the cylinder 19 is horizontally arranged along the front-to-back direction, and the end of the piston rod is fixedly connected to the thread-picking seat 4. When thread cutting is required, the sewing machine control system controls the cylinder 19 to extend, which drives the thread-picking seat 4 to move forward by a specific stroke. This causes the thread-picking lever 3 on the thread-picking seat 4 to move away from the rotary hook 2, avoiding the movement path of the thread-cutting blade 20 around the rotary hook 2, thereby preventing interference between the thread-cutting blade 20 and the thread-picking lever 3.

[0043] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

[0044] Although this document frequently uses terms such as 1. base; 1a. mounting wall; 1b. slide rail; 2. rotary hook; 3. thread-picking lever; 4. thread-picking seat; 41. mounting hole; 5. cylinder one; 6. drive shaft; 7. bearing; 8. bushing; 81. support step; 9. cam; 10. motor one; 11. tension spring; 12. motor two; 13. thread-picking wheel; 14. guide seat; 15. main shaft; 16. drive shaft; 17. bevel gear pair; 18. belt; 19. cylinder two; 20. thread-cutting blade; 21. needle plate, etc., the possibility of using other terms is not excluded. The use of these terms is merely for the convenience of describing and explaining the essence of this utility model; interpreting them as any additional limitation would contradict the spirit of this utility model.

Claims

1. A thread-picking mechanism for a sewing machine, the sewing machine comprising a base (1) and a rotary hook (2) disposed within the base (1), the thread-picking mechanism comprising a thread-picking lever (3) and a strip-shaped thread-picking seat (4) located on the side of the rotary hook (2), the thread-picking lever (3) being disposed on the thread-picking seat (4) and the end of the thread-picking lever (3) being able to extend above the rotary hook (2) to perform circumferential cyclic movement, characterized in that, The end of the wire guide (4) away from the rotary hook (2) is rotatably mounted on the base (1). The base (1) is also provided with a driving member, which can drive the other end of the wire guide (4) to swing forward horizontally so that the end of the wire guide (3) moves away from the rotary hook (2).

2. The thread-picking mechanism of the sewing machine according to claim 1, characterized in that, The wire-picking mechanism also includes a vertically arranged drive shaft (6). The end of the wire-picking seat (4) away from the rotary hook (2) has a mounting hole (41). The mounting hole (41) is provided with a bearing (7) whose outer ring is tightly fitted with the mounting hole (41). A bushing (8) is fixedly sleeved on the drive shaft (6). The longitudinal section of the bushing (8) is convex, and a support step (81) is formed on its outer peripheral wall. The inner ring of the bearing (7) is tightly fitted with the outer peripheral wall of the bushing (8), and the lower end face of the inner ring of the bearing (7) abuts against the support step (81).

3. The thread-pushing mechanism of a sewing machine according to claim 1 or 2, characterized in that, The driving component is a cylinder (5) fixedly connected to the base (1) and located behind the wire-picking seat (4). The piston rod of the cylinder (5) is horizontally arranged and its end is hinged to the wire-picking seat (4).

4. The thread-picking mechanism of the sewing machine according to claim 1 or 2, characterized in that, The driving component includes a cam (9) located on the rear side of the wire guide (4) and horizontally arranged, and a motor (10) for driving the cam (9) to rotate. A tension spring (11) is provided between the wire guide (4) and the base (1). Under the action of the tension spring (11), the rear side of the wire guide (4) always abuts against the outer peripheral surface of the cam (9).

5. The thread shifting mechanism of a sewing machine according to claim 2, wherein The upper side of the thread-picking seat (4) is provided with a guide seat (14) that can rotate horizontally. The thread-picking rod (3) is slidably connected to the guide seat (14) along the axial direction. The thread-picking mechanism also includes a second motor (12) fixedly connected to the base (1). The lower end of the transmission shaft (6) is coaxially fixedly connected to the rotating shaft of the second motor (12). The upper end of the transmission shaft (6) is fixedly connected to a thread-picking wheel (13). The end of the thread-picking rod (3) away from the rotary hook (2) is hinged to the eccentric position of the thread-picking wheel (13).

6. The thread guiding mechanism of a sewing machine according to claim 2, wherein This sewing machine also includes a main shaft (15) set in the base (1), and a guide seat (14) that can rotate horizontally is provided on the upper side of the thread guide seat (4). The thread guide rod (3) is slidably connected to the guide seat (14) along the axial direction. This thread guide mechanism also includes a drive shaft (16) parallel to the main shaft (15). The main shaft (15) can drive the drive shaft (16) to rotate synchronously. The front end of the drive shaft (16) is connected to the lower end of the transmission shaft (6) through a bevel gear pair (17). The upper end of the transmission shaft (6) is fixedly connected to a thread guide wheel (13). The end of the thread guide rod (3) away from the rotary hook (2) is hinged to the eccentric position of the thread guide wheel (13).

7. The thread guiding mechanism of a sewing machine according to claim 3, wherein The base (1) has a vertically arranged mounting wall (1a) located behind the dial seat (4), and the cylinder (5) is located behind the mounting wall (1a) and the piston rod of the cylinder (5) passes through the mounting wall (1a) and is hinged to the dial seat (4).

8. The thread shifting mechanism of a sewing machine according to claim 6, wherein The main shaft (15) and the front end of the drive shaft (16) are connected by a belt (18).

9. A thread-picking mechanism for a sewing machine, the sewing machine comprising a base (1) and a rotary hook (2) disposed within the base (1), the thread-picking mechanism comprising a thread-picking lever (3) and a strip-shaped thread-picking seat (4) located on the side of the rotary hook (2), the thread-picking lever (3) being disposed on the thread-picking seat (4) and the end of the thread-picking lever (3) being able to extend above the rotary hook (2) to perform circumferential cyclic movement, characterized in that, The dial seat (4) is slidably mounted on the base (1) in the horizontal direction. The base (1) is also provided with a driving member. The driving member can drive the dial seat (4) to move so that the end of the dial rod (3) moves away from the rotary hook (2).

10. The thread shifting mechanism of a sewing machine according to claim 9, wherein The base (1) has a slide rail (1b) arranged horizontally in the front-back direction. The wire-picking seat (4) is slidably connected to the slide rail (1b). The driving component is a cylinder two (19) fixedly connected to the base (1) and located behind the wire-picking seat (4). The piston rod of the cylinder two (19) is arranged horizontally in the front-back direction and its end is fixedly connected to the wire-picking seat (4).

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