Automatic needle bar separating device and sewing machine

Abstract

This invention provides an automatic needle bar separation device and a sewing machine, belonging to the technical field of sewing equipment. The needle bar includes a left needle bar and a right needle bar. The automatic needle bar separation device includes a sliding shaft with two ends, each end connected to a reset component and a separation component. The separation component includes a mounting base with a sliding block slidably connected to it. The separation component also includes a drive source, and a rotating block is disposed on the mounting base. During the movement of the sliding block driven by the drive source, the rotating block rotates, causing the left needle bar to separate and reset, or causing the right needle bar to separate and reset. This automatic needle bar separation allows the sewing machine to maintain a single-needle sewing state for an extended period, and the electromagnet in the drive source will not overheat and fail.

Description

Technical Field

[0001] This invention belongs to the field of sewing equipment technology, and relates to an automatic needle bar separation device and a sewing machine. Background Technology

[0002] In traditional mechanical needle bar separation structures, needle bar separation and repositioning are generally performed manually to enable corner sewing. The drawbacks are that operators need to control the number of stitches per needle during corner sewing, which can easily lead to excess or insufficient stitches, affecting the appearance of the stitches. Furthermore, manual repositioning reduces sewing efficiency. In some cases, performing the separation action at high speeds can even damage the needle bar clamp assembly.

[0003] In existing technologies, there are also methods that use cylinders as the driving source for left and right separation, buttons as input signals, and electronic control to completely eliminate the problems of the traditional needle bar separation mechanical structure. However, due to the high price of pneumatic components and the fact that the application scenarios must rely on air sources, the pneumatic needle bar separation structure has never been able to be used on a large scale in the market.

[0004] Patent documents CN201310228600.9 and CN201621358269.8 also disclose structures that use electromagnets as a driving source to separate the left and right needle rods. Both patent documents use electromagnets as the driving source, but one uses two electromagnets while the other uses a single bidirectional electromagnet. The principle is the same: when one electromagnet is engaged, the slider moves to its left or right extreme position. The drawback of these electromagnet structures is that the left and right movement of the slider depends entirely on the electromagnet being energized and engaged. Once the electromagnet is de-energized, the slider returns to the center position under the force of the spring, and the needle rods automatically reset to the double needle position.

[0005] In some garment sewing processes, it is necessary to sew a section of stitch with double needles, sew a section of stitch with a single needle, or have the user sew with a single needle for a long time using a double-needle machine. Therefore, in order to maintain single-needle sewing for a long time, the electromagnet must remain in an engaged state for a long time. However, due to the characteristic that electromagnets are prone to overheating and failure when engaged for a long time, electromagnets generally cannot maintain an engagement time of more than 1 minute. Therefore, the above two structures are difficult to maintain a single-needle sewing state for a long time. Summary of the Invention

[0006] In view of the above-mentioned problems existing in the prior art, the present invention provides an automatic needle bar separation device. The technical problem to be solved by the present invention is: how to maintain a single-needle sewing state for a long time.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] An automatic needle bar separation device is disclosed, comprising a left needle bar and a right needle bar. The automatic needle bar separation device includes a sliding shaft with two ends, each end of which is connected to a reset component and a separation component. The separation component includes a mounting base fixed to a machine housing, and a sliding block slidably connected to the mounting base. The separation component further includes a drive source for driving the sliding block to move left and right. A rotatable rotating block is provided on the mounting base. During the movement of the sliding block driven by the drive source, the rotating block rotates, causing the left needle bar to separate and reset, or causing the right needle bar to separate and reset.

[0009] In the aforementioned automatic needle bar separation device, notches are respectively provided on the left and right sides of the rotating block. A lower guide rail and a lower pin are provided in the sliding block. A lower clearance groove is provided on the lower guide rail. When the lower pin and the lower clearance groove are located on the left side of the rotating block, the rotating block is above the lower guide rail; when the lower pin contacts the left side of the rotating block, the lower clearance groove is below the rotating block. The lower pin can push the rotating block to rotate clockwise and engage with the lower pin on the rotating block. In the notch on the left; when the right side wall of the lower clearance groove pushes the rotating block to rotate clockwise, the right side wall of the lower clearance groove engages in the notch on the right side of the rotating block; when the sliding block moves in the opposite direction and the lower part of the rotating block is located in the lower clearance groove, the lower pin and the left side wall of the lower clearance groove can abut against the upper and lower parts of the rotating block respectively; when the right side wall of the lower clearance groove pushes the rotating block to rotate, the lower pin and the lower clearance groove are located on the left side of the rotating block, and the rotating block is located above the lower guide rail.

[0010] In the aforementioned automatic needle bar separation device, the sliding block is further provided with an upper guide rail and an upper pin. The upper guide rail is provided with an upper clearance groove. The upper guide rail and the lower guide rail are arranged opposite to each other. There are two rotating blocks located between the upper guide rail and the lower guide rail.

[0011] The working principle of this automatic needle bar separation device will be explained using the separation and reset of the right needle bar (the separation and reset of the left needle bar is similar) as an example:

[0012] Initial state 1: The sliding block is in the middle position, and the two needles on the needle bar are in the reset state, i.e., the double needle state. At this time, the lower pin and the lower clearance groove are located on the left side of the rotating block, and the rotating block is located above the lower guide rail.

[0013] Right Limit State: The drive source drives the sliding block to move to the rightmost position (the stroke B of the component in the drive source is greater than or equal to the maximum stroke A of the sliding block to the right). During the movement of the sliding block to the right, the lower clearance groove on the lower guide rail gradually moves to the bottom of the rotating block, making room for the rotation of the rotating block. At the same time, the lower pin on the sliding block also moves. When the lower pin contacts the notch on the left side of the rotating block, the lower clearance groove is located below the rotating block. Then the lower pin will push the rotating block to rotate clockwise until both surfaces of the notch on the left side of the rotating block are in contact with the lower pin. In this way, the sliding block will no longer move to the right. At this time, part of the rotating block falls into the lower clearance groove of the lower guide rail. At this time, under the action of the drive source, the component in the reset assembly will move to the right by a distance C. The needle bar fixing assembly is in the right limit position, and the right needle bar moves to the right to achieve separation.

[0014] Right Separation State: The spring drives the sliding block to move a distance D to the left. During the movement of the sliding block, the right side wall of the lower relief groove on the lower guide rail first contacts the surface of the notch on the right side of the rotating block. Then, the right side wall of the lower relief groove pushes the rotating block to continue rotating clockwise. As the rotating block rotates, part of the other side of the notch on the right side of the rotating block also contacts the lower guide rail. Due to the limitation of this part, the rotating block can no longer rotate, and the sliding block can no longer move to the left. However, it is still driven by the driving force of the driving source and is still in a state close to the right limit, in the separation state at the right needle bar. (This is because AD≥C, so even if the sliding block moves a small distance to the left, the final stroke of the sliding block is still greater than the stroke required for the needle bar to separate.)

[0015] This automatic needle bar separation device uses the aforementioned rotating block and lower relief groove on the lower guide rail, which enables the sewing machine to maintain a single-needle sewing state for a long time. Even with long-term single-needle sewing, the electromagnet in the drive source will not overheat or fail, thus solving the technical defects of the existing technology.

[0016] Right reset state: When switching from a single needle back to a dual needle, the drive source drives the sliding block to move to the right. During the movement of the sliding block to the right, the lower clearance groove on the lower guide rail reaches below the rotating block, making room for the rotation of the rotating block. The lower pin on the sliding block contacts the side of the rotating block, and the lower pin slowly pushes the rotating block to rotate clockwise. A part of the rotating block enters the lower clearance groove of the lower guide rail until the side of the rotating block contacts both the lower pin and the right side wall of the clearance groove on the lower guide rail. After there are two contact points, the rotating block and the sliding block can no longer move. At this time, the reset component does not move and is still in the right limit position, and the right needle bar separates.

[0017] Initial State 2: Driven by the spring, the sliding block moves to the left. As the rotating block falls into the lower relief groove of the lower guide rail, during the leftward movement, when the side of the rotating block contacts the side wall of the lower relief groove of the lower guide rail, the right side wall of the lower relief groove pushes the rotating block to continue rotating clockwise until all components of the drive source are reset, the sliding block stops moving, and the entire mechanical structure returns to its initial state. In fact, the rotating block has rotated 180°. During this process, the reset component returns to the middle position, the sliding block also returns to the middle position, the right needle bar resets, and the needle bar switches from single needle state back to double needle state.

[0018] In the aforementioned automatic needle bar separation device, the reset component further includes a switch, which is equipped with a left separation button, a right separation button, and a reset button.

[0019] The switch has three buttons: a left separation button, a right separation button, and a reset button. Using these three buttons in conjunction with the electronic control allows for needle bar separation. The difference between the automatic reset mode and the manual separation mode is that there is an automatic part in the middle where the electronic control completes the corner sewing action. In the manual separation mode, this part of the operation is performed by the user. When the user no longer needs single-needle separation, they can press the reset button to switch back to double-needle separation.

[0020] This automatic needle bar separation device can be controlled by a button to automatically separate the left and right needle bars without manual reset. It provides accurate needle count at corners and produces aesthetically pleasing stitches. It is also independent of air supply, has a simple structure, low cost, and is applicable to all usage scenarios on the market.

[0021] In the aforementioned automatic needle bar separation device, the notch on the left side and the notch on the right side of the rotating block have the same shape and are symmetrically arranged. When the rotating block rotates 180°, the positions of the notch on the left side and the notch on the right side of the rotating block are interchanged, and the notch is V-shaped or U-shaped.

[0022] The notches are identical in shape and located on both sides of the rotating block. The entire rotating block has a symmetrical structure. This structure ensures that the rotating block rotates 180° after each separation and reset action of the needle bar, preparing for the next separation, and that the stroke of the rotating block does not change.

[0023] In the aforementioned automatic needle bar separation device, the lower relief groove includes a bottom wall and a side wall, and the angle between the side wall and the bottom wall is a right angle, an acute angle, or an obtuse angle.

[0024] In the aforementioned automatic needle bar separation device, when the rotating block is located above the lower guide rail, there is a gap between the bottom of the rotating block and the top of the lower guide rail.

[0025] A certain gap is left between the bottom of the rotating block and the top of the lower guide rail. This structure ensures that the rotating block does not rotate before the lower pin contacts the rotating block.

[0026] In the aforementioned automatic needle bar separation device, a groove is provided on the mounting base, a sliding block is slidably connected in the groove, a rotating block is located in the groove, and a cover plate is installed on the mounting base. The cover plate is located at the opening of the groove and extends towards the middle of the groove.

[0027] The groove guides and limits the sliding block, improving its stability during movement. The cover plate blocks the rotating block, preventing it from falling off the mounting base.

[0028] In the aforementioned automatic needle bar separation device, the reset assembly includes a sliding shaft frame, a support plate mounted on the sliding shaft frame, and a slider mounted on the support plate. The sliding shaft frame includes a main body, which has a bent portion. The sliding shaft passes through the bent portion and is provided with two springs and two retaining rings. The springs are located on the left and right sides of the bent portion, respectively. The inner end of each spring abuts against the bent portion, and the outer end of each spring abuts against a retaining ring.

[0029] The right needle bar is mounted on the slider. The drive source drives the sliding shaft to move to the right. The sliding shaft drives the sliding shaft bracket and the support plate to move to the right. The slider on the support plate moves to the right, thus separating the right needle bar.

[0030] The snap ring and the spring form a stroke buffer structure. The spring is mounted on the sliding shaft. When the sliding shaft moves to the left or right, the spring on the right side or the spring on the left side of the bent part is compressed. Under the action of the spring force, the sliding shaft can drive the sliding shaft bracket to move to the left or right.

[0031] Initially, the stroke A of the sliding block is much larger than the stroke C required for the slide shaft to separate. If a rigid connection is used, the extra stroke will cause severe deformation of the component (support plate) connected to the slide shaft. However, by using the above-mentioned stroke buffer structure to make a soft connection between the sliding shaft and the slide shaft, the above problem can be well avoided.

[0032] In the aforementioned automatic needle bar separation device, two strip-shaped grooves are provided on the main body of the sliding shaft frame, and a shaft screw is respectively installed on each of the strip-shaped grooves, and the shaft screw is fixed to the machine housing.

[0033] The sliding bracket is fixed to the housing by a pivot screw, allowing it to slide left and right. The bracket has two slots, which, in conjunction with the pivot screw, restrict the sliding shaft's movement to left and right. By controlling the length of these slots, the travel distance of the sliding shaft matches the travel distance of the slider. Therefore, even if the sliding shaft's travel distance is too large, the slots will limit the bracket's movement, ensuring it doesn't exceed the slider's required travel distance. Furthermore, because it's not a rigid connection, the sliding shaft can continue to move even after the bracket is stopped, thus buffering this travel distance.

[0034] In the aforementioned automatic needle bar separation device, the support plate has a second bending portion, and a second strip groove is provided on the second bending portion. A screw passes through the second strip groove, and the screw fixes the bending portion to the slide frame.

[0035] The support plate is fixed to the slide rail with screws. The support plate has a second slot, which is used to adjust the initial position of the slider. Since each machine's processing and assembly will inevitably differ, the left and right positions of the slider and slide rail may vary each time. It's possible that the slider reaches the separation position, but the slide rail cannot. Therefore, the second slot allows adjustment of the slider's initial position, enabling the automatic needle bar separation device to achieve its separation function even with assembly errors, greatly improving its adaptability.

[0036] In the aforementioned automatic needle bar separation device, a mounting frame is installed on the mounting base, the driving source includes an iron core, a connecting frame is fixed on the iron core, a sliding block is fixed on the connecting frame, one end of the sliding shaft is installed on the connecting frame, and the other end of the sliding shaft is installed on the sliding shaft bracket. The sliding shaft bracket is movably connected to the housing. A left separation electromagnet and a right separation electromagnet are respectively installed on both sides of the iron core. The left and right separation electromagnets are mounted on the mounting frame. Two springs are sleeved on the iron core, one spring located between the left separation electromagnet and the connecting frame, and the other spring located between the right separation electromagnet and the connecting frame.

[0037] When the left separation electromagnet is attracted for the first time, the connecting frame moves the sliding block to the right. When the left separation electromagnet is released for the first time, the sliding block moves to the left under the action of the spring force because the second spring on the right side of the iron core is in a compressed state. When the left separation electromagnet is attracted for the second time, the sliding block moves to the right. When the left separation electromagnet is released for the second time, the sliding block slowly moves to the left under the action of the spring force because the second spring on the right side of the iron core is in a compressed state.

[0038] As another embodiment, the left and right separation electromagnets in the drive source can also be replaced by bidirectional electromagnets.

[0039] The present invention also provides a sewing machine, which includes any of the above-described automatic needle bar separation devices.

[0040] Compared with the prior art, the advantages of the present invention are as follows:

[0041] 1. This automatic needle bar separation device adopts a mechanical structure of rotating block and clearance groove on guide rail, which enables the sewing machine to maintain a single-needle sewing state for a long time. Even if single-needle sewing is carried out for a long time, the electromagnet in the drive source will not overheat and fail, thus solving the technical defects of the existing technology.

[0042] 2. This automatic needle bar separation device can be controlled by a button to automatically separate the left and right needle bars without manual reset. It has accurate needle count at corners and produces beautiful stitches. It does not rely on an air source, has a simple structure, low cost, and can be applied to all application scenarios on the market. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the automatic needle bar separation device installed on the machine housing;

[0044] Figure 2 This is an exploded view of the automatic needle bar separation device;

[0045] Figure 3 This is a schematic diagram of the rotating block in different states;

[0046] Figure 4 This is a structural diagram of the mounting base;

[0047] Figure 5 This is a schematic diagram of the sliding block structure;

[0048] Figure 6 This is a schematic diagram showing the connection between the sliding shaft and the sliding shaft bracket.

[0049] In the diagram: 1. Sliding shaft, 2. Reset assembly, 3. Separation assembly, 4. Mounting base, 5. Sliding block, 6. Drive source, 7. Rotating block, 8. Notch, 9. Pin screw, 10. Lower guide rail, 11. Lower pin, 12. Lower clearance groove, 13. Switch, 14. Slide groove, 15. Cover plate, 16. Sliding shaft bracket, 17. Support plate, 18. Slider, 19. Main body, 20. Bending part one, 21. Spring one, 22. Snap ring, 23. Strip groove one, 24. Shaft screw, 25. Bending part two, 26. Strip groove two, 27. Screw, 28. Mounting bracket, 29. Iron core, 30. Connecting bracket, 31. Left separation electromagnet, 32. Right separation electromagnet, 33. Spring two, 34. Right needle rod, 35. Left needle rod, 36. Housing, 37. Upper guide rail, 38. Upper pin, 39. Upper clearance groove. Detailed Implementation

[0050] The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0051] like Figure 1-5 As shown, the needle bar includes a left needle bar 35 and a right needle bar 34. The automatic needle bar separation device includes a sliding shaft 1 with two ends, each end of which is connected to a reset component 2 and a separation component 3. The separation component 3 includes a mounting base 4, which is fixed on the housing 36. A sliding block 5 is slidably connected to the mounting base 4. The separation component 3 also includes a drive source 6 that drives the sliding block 5 to move left and right. A rotatable rotating block 7 is provided on the mounting base 4. During the process of the drive source 6 driving the sliding block 5 to move, the rotating block 7 rotates, causing the left needle bar 35 to separate and reset, or causing the right needle bar 34 to separate and reset.

[0052] Specifically, notches 8 are provided on the left and right sides of the rotating block 7, and a lower guide rail 10 and a lower pin 11 are provided in the sliding block 5. A lower clearance groove 12 is provided on the lower guide rail 10. When the lower pin 11 and the lower clearance groove 12 are located on the left side of the rotating block 7, the rotating block 7 is located above the lower guide rail 10; when the lower pin 11 contacts the left side of the rotating block 7, the lower clearance groove 12 is located below the rotating block 7. The lower pin 11 can push the rotating block 7 to rotate clockwise and make the lower pin 11 engage with the notch on the left side of the rotating block 7. In step 8; when the right side wall of the lower clearance groove 12 pushes the rotating block 7 to rotate clockwise, the right side wall of the lower clearance groove 1 engages in the notch 8 on the right side of the rotating block 7; when the sliding block 5 moves in the opposite direction and the lower part of the rotating block 7 is located in the lower clearance groove 12, the left side wall of the lower pin 11 and the lower clearance groove 12 can abut against the upper and lower parts of the rotating block 7 respectively; when the right side wall of the lower clearance groove 12 pushes the rotating block 7 to rotate, the lower pin 11 and the lower clearance groove 12 are located on the left side of the rotating block 7, and the rotating block 7 is located above the lower guide rail 10.

[0053] like Figure 2 and 3 As shown, in this embodiment, the sliding block 5 is also provided with an upper guide rail 37 and an upper pin 38. An upper clearance groove 39 is provided on the upper guide rail 37. The upper guide rail 37 and the lower guide rail 10 are arranged opposite to each other. There are two rotating blocks 7 located between the upper guide rail 37 and the lower guide rail 10.

[0054] like Figure 2 As shown, in this embodiment, the reset component 2 also includes a switch 13, which is provided with a left separation button, a right separation button and a reset button.

[0055] Switch 13 has three buttons: a left separation button, a right separation button, and a reset button. Using these three buttons in conjunction with the electronic control enables the needle bar separation function. The difference between the automatic reset mode and the manual separation mode is that there is a section in the middle where the electronic control automatically completes the corner sewing action. In the manual separation mode, this operation is performed by the user. When the user no longer needs single-needle separation, they can press the reset button to switch back to double-needle separation.

[0056] This automatic needle bar separation device can be controlled by a button to automatically separate the left and right needle bars without manual reset. It provides accurate needle count at corners and produces aesthetically pleasing stitches. It is also independent of air supply, has a simple structure, low cost, and is applicable to all usage scenarios on the market.

[0057] like Figure 4 As shown, in this embodiment, the notch 8 on the left side of the rotating block 7 and the notch 8 on the right side of the rotating block 7 have the same shape and are symmetrically arranged. When the rotating block 7 rotates 180°, the positions of the notch 8 on the left side of the rotating block 7 and the notch 8 on the right side of the rotating block 7 are interchanged, and the notch 8 is V-shaped or U-shaped.

[0058] The notches 8 are identical in shape and located on both sides of the rotating block 7. The entire rotating block 7 has a symmetrical structure. This structure allows the rotating block 7 to rotate 180° after each separation and reset action of the needle bar, preparing for the next separation, and ensuring that the stroke of the rotating block 7 does not change.

[0059] like Figure 5 As shown, in this embodiment, the lower clearance groove 12 includes a bottom wall and a side wall, and the angle between the side wall and the bottom wall is a right angle, an acute angle, or an obtuse angle.

[0060] Preferably, when the rotating block 7 is located above the lower guide rail 10, there is a gap between the bottom of the rotating block 7 and the top of the lower guide rail 10.

[0061] A certain gap is left between the bottom of the rotating block 7 and the top of the lower guide rail 10. This structure ensures that the rotating block 7 does not rotate before the lower pin 11 contacts the rotating block 7.

[0062] like Figure 2 and 4 As shown, in this embodiment, the mounting base 4 is provided with a sliding groove 14, the sliding block 5 is slidably connected in the sliding groove 14, the rotating block 7 is located in the sliding groove 14, and the mounting base 4 is provided with a cover plate 15, which is located at the opening of the sliding groove 14 and extends toward the middle of the sliding groove 14.

[0063] The slide groove 14 guides and limits the sliding block 5, which can improve the stability of the sliding block 5 when it moves. The cover plate 15 blocks the rotating block 7 and prevents the sliding block 5 from falling off the mounting base 4.

[0064] like Figure 2 As shown, in this embodiment, the reset assembly 2 includes a sliding shaft frame 16, a support plate 17 is mounted on the sliding shaft frame 16, and a slider 18 is mounted on the support plate 17. The sliding shaft frame 16 includes a main body 19, which has a bent portion 20. The sliding shaft 1 passes through the bent portion 20. The sliding shaft 1 is provided with two springs 21 and two retaining rings 22. The springs 21 are located on the left and right sides of the bent portion 20, respectively. The inner end of each spring 21 abuts against the bent portion 20, and the outer end of each spring 21 abuts against a retaining ring 22.

[0065] The right needle rod 34 is mounted on the slider 18. The drive source 6 drives the sliding shaft 1 to move to the right. The sliding shaft 1 drives the sliding shaft frame 16 and the support plate 17 to move to the right. The slider 18 on the support plate 17 moves to the right, thereby separating the right needle rod 34.

[0066] The snap ring 22 and the spring 21 form a stroke buffer structure. The spring 21 is sleeved on the sliding shaft 1. When the sliding shaft 1 moves to the left or right, the spring 21 on the right side or the spring 21 on the left side of the bent part 20 is compressed. Under the action of the spring force of the spring 21, the sliding shaft 1 can drive the sliding shaft bracket 16 to move to the left or right.

[0067] Initially, the stroke A of the sliding block 5 is much larger than the stroke C required for the slide shaft 16 to separate. If a rigid connection is used, the extra stroke will cause severe deformation of the component (support plate 17) connected to the slide shaft 16. However, by using the above-mentioned stroke buffer structure to make a soft connection between the sliding shaft 1 and the slide shaft 16, the above problem can be well avoided.

[0068] like Figure 6 As shown, in this embodiment, the main body 19 of the sliding shaft bracket 16 has two strip-shaped grooves 23, and each strip-shaped groove 23 is provided with a shaft screw 24, which is fixed to the housing 36.

[0069] The slide bracket 16 is fixed to the housing 36 by the shaft screw 24, allowing it to slide left and right. The slide bracket 16 has two slots 23, which, in conjunction with the shaft screw 24, restrict the sliding shaft 1 to left and right movement. By controlling the length of the slots 23, the travel distance of the sliding shaft 1 is made the same as that of the slider 18. Therefore, even if the travel distance of the sliding shaft 1 is too large, the limiting effect of the slots 23 ensures that the travel distance of the slide bracket 16 will not exceed the required travel distance of the slider 18. Furthermore, because it is not a rigid connection, even after the slide bracket 16 is fixed, the sliding shaft 1 can still continue to move, thus buffering this travel distance.

[0070] like Figure 2 and 6As shown, in this embodiment, the support plate 17 has a second bending portion 25, and a second strip groove 26 is provided on the second bending portion 25. A screw 27 is inserted in the second strip groove 26, and the screw 27 fixes the bending portion to the slide frame 16.

[0071] The support plate 17 is fixed to the slide rail 16 by screws 27. The support plate 17 has a slot 26, which is used to adjust the initial position of the slider 18. Since each machine's processing and assembly will inevitably differ, the left and right positions of the slider 18 and slide rail 16 may vary each time. It's possible that the slider 18 reaches the separation position, but the slide rail 16 cannot. Therefore, the slot 26 allows adjustment of the initial position of the slider 18, enabling the automatic needle bar separation device to achieve the separation function even with assembly errors, thus greatly improving adaptability.

[0072] like Figure 2 As shown, in this embodiment, a mounting bracket 28 is installed on the mounting base 4, the drive source 6 includes an iron core 29, a connecting bracket 30 is fixed on the iron core 29, the two can be fixed together by pins and screws 9, a sliding block 5 is fixed on the connecting bracket 30, one end of the sliding shaft 1 is installed on the connecting bracket 30, the other end of the sliding shaft 1 is installed on the sliding shaft bracket 16, the sliding shaft bracket 16 is movably connected to the housing 36, a left separation electromagnet 31 and a right separation electromagnet 32 ​​are respectively installed on both sides of the iron core 29, the left separation electromagnet 31 and the right separation electromagnet 32 ​​are installed on the mounting bracket 28, and two springs 33 are sleeved on the iron core 29, one spring 33 is located between the left separation electromagnet 31 and the connecting bracket 30, and the other spring 33 is located between the right separation electromagnet 32 ​​and the connecting bracket 30.

[0073] When the left separation electromagnet 31 is attracted for the first time, the connecting frame 30 drives the sliding block 5 to move to the right. When the left separation electromagnet 31 is released for the first time, since the second spring 33 on the right side of the iron core 29 is in a compressed state, the sliding block 5 will move to the left under the action of the spring force. When the left separation electromagnet 31 is attracted for the second time, the sliding block 5 moves to the right. When the left separation electromagnet 31 is released for the second time, since the second spring 33 on the right side of the iron core 29 is in a compressed state, the sliding block 5 will slowly move to the left under the action of the spring force.

[0074] As another embodiment, the left separation electromagnet 31 and the right separation electromagnet 32 ​​in the drive source 6 can also be replaced by bidirectional electromagnets.

[0075] like Figure 3 As shown, the working principle of this automatic needle bar separation device is explained using the separation and reset of the right needle bar 34 (the separation and reset of the left needle bar 35 is similar) as an example:

[0076] Initial state 1: Sliding block 5 is in the middle position, and the two needles on the needle bar are in the reset state, i.e., double needle state. At this time, the lower pin 11 and the lower clearance groove 12 are located on the left side of the rotating block 7, and the rotating block 7 is located above the lower guide rail 10. At this time, both the two springs 33 on the iron core 29 and the two springs 21 on the sliding shaft 1 are in a state of force balance.

[0077] Right limit state: The left separation electromagnet 31 engages for the first time, and the left separation electromagnet 31 (drive source 6) drives the sliding block 5 to move to the rightmost position. The stroke B of the component in drive source 6 (left separation electromagnet 31) is greater than or equal to the maximum stroke A of the sliding block 5 moving to the right. During the movement of the sliding block 5 to the right, the lower clearance groove 12 on the lower guide rail 10 gradually moves to the bottom of the rotating block 7, making room for the rotation of the rotating block 7. At the same time, the lower pin 11 on the sliding block 5 also moves. When the lower pin 11 contacts the notch 8 on the left side of the rotating block 7, the lower clearance groove 12 is located at the bottom of the rotating block 7. Below, the lower pin 11 will then push the rotating block 7 to rotate clockwise until both surfaces of the notch 8 on the left side of the rotating block 7 are in contact with the lower pin 11. In this way, the sliding block 5 will no longer move to the right. At this time, part of the rotating block 7 will fall into the lower relief groove 12 of the lower guide rail 10. At this time, the second spring 33 on the right side of the iron core 29 is in a compressed state, and the first spring 21 on the left side of the sliding shaft 1 is in a compressed state. Under the action of the spring force on the left side of the sliding shaft 1 (under the action of the drive source 6), the sliding shaft bracket 16 will move to the right by a distance C. The slider 18 is at the right limit position, and the right needle bar is separated.

[0078] Right separation state: When the left separation electromagnet 31 is released for the first time, since the spring 33 on the right side of the iron core 29 is in a compressed state, the sliding block 5 will move a distance D to the left under the action of the spring force. During the movement of the sliding block 5, the right side wall of the lower relief groove 12 on the lower guide rail 10 first contacts the surface of the notch 8 on the right side of the rotating block 7. Then the right side wall of the lower relief groove 12 pushes the rotating block 7 to continue to rotate clockwise. As the rotating block 7 rotates, the other part of the notch 8 on the right side of the rotating block 7 also contacts the lower guide rail 10. Due to the limitation of this part, the rotating block 7 cannot continue to rotate, and the sliding block 5 cannot continue to move to the left. However, it is still subject to the spring force to the left, so the sliding block 5 remains in a stopped state. At this time, the spring on the right side of the iron core 29 is still in a compressed state, the spring 21 on the left side of the sliding shaft 1 is in a compressed state, the sliding shaft bracket 16 does not move at this time and is still in the right limit position, and the right needle bar is separated. This is because AD≥C, meaning that even if the slider 5 moves a small distance to the left, the final stroke of the slider 5 is still greater than the stroke required for needle bar separation. In other words, the spring force generated on the left side of the slide bracket 16 is always greater than the spring force generated on the right side, thus keeping the slide bracket 16 stationary and achieving needle bar separation.

[0079] This automatic needle bar separation device uses the aforementioned rotating block 7 and the upper and lower clearance grooves 12 of the lower guide rail 10, which enables the sewing machine to maintain a single-needle sewing state for a long time. Even with long-term single-needle sewing, the electromagnet in the drive source 6 will not overheat or fail, thus solving the technical defects of the existing technology.

[0080] Right reset state: When it is necessary to switch from single needle back to double needle, the left separation electromagnet 31 is attracted for the second time, and the drive source 6 drives the sliding block 5 to move to the right. During the movement of the sliding block 5 to the right, the lower clearance groove 12 on the lower guide rail 10 is below the rotating block 7, which makes room for the rotation of the rotating block 7. The lower pin 11 on the sliding block 5 contacts the side of the rotating block 7, and the lower pin 11 slowly pushes the rotating block 7 to rotate clockwise. A part of the rotating block 7 enters the lower clearance groove 12 of the lower guide rail 10 until the side of the rotating block 7 contacts both the lower pin 11 and the right side wall of the clearance groove on the lower guide rail 10. After there are two contact points, the rotating block 7 and the sliding block 5 can no longer move. At this time, the spring on the right side of the iron core 29 is still in a compressed state, and the component of the reset assembly 2 (sliding shaft bracket 16) does not move and is still in the right limit position, and the right needle bar is separated.

[0081] Initial State 2: Driven by the drive source 6 (i.e., the left separation electromagnet 31 is released for the second time, and the spring on the right side of the iron core 29 is in a compressed state, under the action of the spring force), the sliding block 5 moves to the left. As the rotating block 7 falls into the lower relief groove 12 of the lower guide rail 10, during the leftward movement, when the side of the rotating block 7 contacts the side wall of the lower relief groove 12 of the lower guide rail 10, the right side wall of the lower relief groove 12 pushes the rotating block 7 to continue rotating clockwise until the spring forces on both sides of the iron core 29 are balanced (the components of the drive source 6 are reset), the movement of the sliding block 5 stops, and the entire mechanical structure returns to the initial state. In fact, the rotating block 7 has rotated 180°. This is why the rotating block 7 needs to be symmetrical. As the sliding block 5 moves to the left, the sliding shaft 1 also slowly moves to the left. The spring force generated by the left spring 21 of the sliding shaft bracket 16 gradually becomes less than the spring force generated by the right spring 21. Under the action of the right spring force, the sliding shaft bracket 16 returns to the middle position during this process, the slider 18 also returns to the middle position, the right needle bar resets, and the needle bar switches from the single needle state back to the double needle state.

[0082] The present invention also provides a sewing machine that includes any of the above-described automatic needle bar separation devices.

[0083] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention 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 the invention or exceeding the scope defined by the appended claims.

Claims

1. A needle bar automatic separation device, the needle bar comprising a left needle bar (35) and a right needle bar (34), the needle bar automatic separation device comprising a sliding shaft (1), the sliding shaft (1) having two ends and a reset assembly (2) and a separation assembly (3) being connected to each end respectively, characterized in that, The reset assembly (2) includes a sliding bracket (16), on which a slider (18) is mounted. The right needle rod (34) is mounted on the slider (18). The drive source (6) drives the sliding shaft (1) to move to the right. The sliding shaft (1) drives the sliding bracket (16) to move to the right and the slider (18) to move to the right, thereby separating the right needle rod (34). The separation assembly (3) includes a mounting base (4), which is fixed on the housing (36). A sliding block (5) is slidably connected to the mounting base (4). The separation assembly (3) also includes a mechanism to drive the sliding block (5) to move left and right. A driving source (6) is provided on the mounting base (4), and a rotatable rotating block (7) is provided on the mounting base (4). During the process of the driving source (6) driving the sliding block (5) to move, the rotating block (7) rotates, causing the right needle rod (34) to separate and reset. The left and right sides of the rotating block (7) are respectively provided with notches (8). The sliding block (5) is provided with a lower guide rail (10) and a lower pin (11). The lower guide rail (10) is provided with a lower clearance groove (12). When the lower pin (11) and the lower clearance groove (12) are located on the left side of the rotating block (7), the rotating block (7) is located on the lower guide rail (6). Above 10); when the lower pin (11) contacts the left side of the rotating block (7), the lower clearance groove (12) is located below the rotating block (7), and the lower pin (11) can push the rotating block (7) to rotate clockwise and make the lower pin (11) engage in the notch (8) on the left side of the rotating block (7); after the right side wall of the lower clearance groove (12) pushes the rotating block (7) to rotate clockwise, the right side wall of the lower clearance groove (12) engages in the notch (8) on the right side of the rotating block (7), the rotating block (7) cannot continue to rotate, and the sliding block (5) cannot continue to move to the left, and the sliding block (5) remains. In the stopped state, the sliding bracket (16) does not move and remains in the right limit position, and the right needle rod (34) is separated. When the sliding block (5) moves in the opposite direction and the lower part of the rotating block (7) is located in the lower relief groove (12), the left side wall of the lower pin (11) and the lower relief groove (12) abut against the upper and lower parts of the rotating block (7) respectively. When the right side wall of the lower relief groove (12) pushes the rotating block (7) to rotate, the lower pin (11) and the lower relief groove (12) are located on the left side of the rotating block (7), and the rotating block (7) is located above the lower guide rail (10), thus realizing the reset of the right needle rod (34).

2. A needle bar automatic disconnect device according to claim 1, characterized in that The sliding block (5) is also provided with an upper guide rail (37) and an upper pin (38). An upper clearance groove (39) is provided on the upper guide rail (37). The upper guide rail (37) and the lower guide rail (10) are arranged opposite to each other. There are two rotating blocks (7) located between the upper guide rail (37) and the lower guide rail (10).

3. The automatic needle bar separation device according to claim 1, characterized in that, The reset component (2) also includes a switch (13), which is provided with a left separation button, a right separation button and a reset button.

4. The automatic needle bar separation device according to claim 1, characterized in that, The notch (8) on the left side of the rotating block (7) and the notch (8) on the right side of the rotating block (7) have the same shape and are symmetrically arranged. When the rotating block (7) rotates 180°, the positions of the notch (8) on the left side of the rotating block (7) and the notch (8) on the right side of the rotating block (7) are interchanged, and the notch (8) is V-shaped or U-shaped.

5. The automatic needle bar separation device according to claim 1, characterized in that, The lower clearance groove (12) includes a bottom wall and a side wall, and the angle between the side wall and the bottom wall is a right angle, an acute angle or an obtuse angle.

6. The automatic needle bar separation device according to claim 1, characterized in that, When the rotating block (7) is above the lower guide rail (10), there is a gap between the bottom of the rotating block (7) and the top of the lower guide rail (10).

7. An automatic needle bar separation device according to any one of claims 1-6, characterized in that, The mounting base (4) has a sliding groove (14), the sliding block (5) is slidably connected in the sliding groove (14), the rotating block (7) is located in the sliding groove (14), and a cover plate (15) is installed on the mounting base (4). The cover plate (15) is located at the opening of the sliding groove (14) and extends towards the middle of the sliding groove (14).

8. The automatic needle bar separation device according to claim 1, characterized in that, The reset assembly (2) includes a slide frame (16), on which a support plate (17) is mounted, and on which a slider (18) is mounted. The slide frame (16) includes a main body (19), which has a bent portion (20). The sliding shaft (1) passes through the bent portion (20). The sliding shaft (1) is provided with two springs (21) and two retaining rings (22). The springs (21) are located on the left and right sides of the bent portion (20), respectively. The inner end of each spring (21) abuts against the bent portion (20), and the outer end of each spring (21) abuts against a retaining ring (22).

9. The automatic needle bar separation device according to claim 8, characterized in that, The main body (19) of the sliding shaft bracket (16) has two strip grooves (23), and each strip groove (23) is provided with a shaft screw (24), which is fixed to the housing (36).

10. The automatic needle bar separation device according to claim 8, characterized in that, The support plate (17) has a second bending part (25), and a second strip groove (26) is provided on the second bending part (25). A screw (27) is provided in the second strip groove (26), and the screw (27) fixes the bending part on the slide frame (16).

11. The automatic needle bar separation device according to claim 1, characterized in that, The mounting base (4) is equipped with a mounting bracket (28). The drive source (6) includes an iron core (29). A connecting bracket (30) is fixed on the iron core (29). The sliding block (5) is fixed on the connecting bracket (30). One end of the sliding shaft (1) is mounted on the connecting bracket (30). The other end of the sliding shaft (1) is mounted on the sliding shaft bracket (16). The sliding shaft bracket (16) is movably connected to the housing (36). A left separation electromagnet (31) and a right separation electromagnet (32) are respectively mounted on both sides of the iron core (29). The left separation electromagnet (31) and the right separation electromagnet (32) are mounted on the mounting bracket (28). Two springs (33) are sleeved on the iron core (29). One spring (33) is located between the left separation electromagnet (31) and the connecting bracket (30). The other spring (33) is located between the right separation electromagnet (32) and the connecting bracket (30).

12. A sewing machine, characterized in that, The sewing machine includes an automatic needle bar separation device as described in any one of claims 1-11.

Images