Sewing starting and post-sewing thread trimming mechanism and sewing machine

Abstract

The sewing starting and post-sewing thread trimming mechanism is provided with a sewing starting and thread trimming driver and a machine needle, the sewing starting and thread trimming driver is fixedly installed on a base of the sewing machine, and a sewing starting movable cutter is provided with a needle falling position and a movable cutter edge; when a sewing thread end needs to be trimmed, under the control of a control system, after a machine needle running in a needle falling position is separated from the needle falling position and is higher than a sewing movable cutter, the sewing movable cutter moves, so that the sewing thread end is transferred to the cutting edge of the movable cutter from the position abutting against the needle falling position, and the sewing movable cutter continues to move to be in contact with the sewing fixed cutter; when a bird nest is generated, the fixed sewing cutter is in contact with the cutting edge of the movable cutter to cut off the sewing thread end, the sewing thread cutting action of the sewing thread cutting mechanism is completed, the sewing thread end can be easily cut as short as possible due to the fact that the needle raising position and the thread cutting position of the machine needle are set to be short, and the effect of well preventing the bird nest from being generated is achieved.

Description

Technical Field

[0001] This utility model relates to the field of sewing machine technology, specifically proposing a sewing start and sewing thread trimming mechanism and a sewing machine. Background Technology

[0002] Sewing machines are equipped with a thread-cutting mechanism. To ensure that the next stitch can start normally, the top thread that forms the starting thread end is usually left a little longer at the end of the previous stitch. Therefore, the first few stitches during sewing will form bad stitches, forming bird's nests. The formation of bird's nests will seriously affect the quality of the sewn products.

[0003] Currently, many technical solutions for preventing bird nests have emerged, most of which use a combination of moving and fixed blades to cut the seam. Since the moving blades have a certain area, the moving and fixed blades, when moved relative to each other, result in a relatively long seam allowance, which makes the bird nest prevention effect generally limited. Utility Model Content

[0004] This application addresses the problem of ineffective bird nest prevention in existing sewing machine thread-cutting mechanisms by proposing a new thread-cutting mechanism. This mechanism comprises a thread-cutting actuator, a thread-cutting fixed blade, and a control system. Its key feature is the addition of a thread-cutting driver and a needle. The thread-cutting driver is fixedly mounted on a base of the sewing machine. The thread-cutting actuator has a needle drop position and a moving blade edge. When thread cutting is required, under the control of the control system, the needle, which is moving within the needle drop position, disengages from the needle drop position and rises above the thread-cutting actuator. The thread-cutting actuator then moves, transferring the thread from its position against the needle drop position to the moving blade edge. The thread-cutting actuator continues to move and contacts the thread-cutting fixed blade, which then cuts the thread, completing the thread-cutting action of the mechanism.

[0005] Furthermore, the moving blade edge is located to the side and rear of the needle drop position.

[0006] Furthermore, the needle insertion point and the moving blade edge overlap, forming the same hole.

[0007] Furthermore, the starting sewing knife and the starting sewing fixed knife are arranged opposite to each other.

[0008] Furthermore, the aforementioned sewing thread cutting driver has an output shaft, on which a sewing thread cutting crank one is fixed. The other end of the sewing thread cutting crank one is provided with a sewing transmission component, which is located inside the fork of the sewing fork-shaped crank. The sewing fork-shaped crank fixes the sewing connecting shaft, and the other end of the sewing connecting shaft fixes the sewing thread cutting crank two. The other end of the sewing thread cutting crank two is hinged to a sewing connecting rod, and the other end of the sewing connecting rod is hinged to a sewing moving knife seat. The sewing moving knife seat is connected to a sewing moving knife fixing part, and a sewing moving knife is fixed on the sewing moving knife fixing part.

[0009] Furthermore, the sewing starter knife holder is sleeved on the lower shaft of the sewing machine, and the sewing starter knife holder and the lower shaft are in clearance fit.

[0010] It also advocates protecting a post-sewing thread-cutting mechanism, which has a post-sewing moving blade, a post-sewing fixed blade, and a thread-cutting driver. The feature is that it also has a post-sewing thread-cutting driver, which is fixed on a base. The post-sewing moving blade has a thread-cutting edge. The post-sewing moving blade and the post-sewing fixed blade are arranged opposite to each other. Under the control of the control system, the post-sewing moving blade moves towards the post-sewing fixed blade, and the post-sewing thread end is cut between the post-sewing moving blade and the thread-cutting edge, thereby realizing automatic post-sewing thread cutting.

[0011] Furthermore, the post-sewing thread cutting driver has an output shaft, on which a post-sewing thread cutting crank one is fixed. The other end of the post-sewing thread cutting crank one is provided with a post-sewing transmission component, which is located in the fork two of the post-sewing fork crank. The post-sewing fork crank is fixedly connected to the post-sewing connecting shaft. The other end of the post-sewing connecting shaft is fixed with a post-sewing thread cutting crank two. The other end of the post-sewing thread cutting crank two is hinged to a post-sewing connecting rod. The other end of the post-sewing connecting rod is hinged to a post-sewing moving knife seat. The post-sewing moving knife seat is connected to a post-sewing moving knife fixing part, and a post-sewing moving knife is fixed on the post-sewing moving knife fixing part.

[0012] Furthermore, the post-sewing moving knife holder is sleeved on the lower shaft, and the post-sewing moving knife holder and the lower shaft are in clearance fit.

[0013] A sewing machine includes the above-mentioned thread-cutting mechanism for starting a sewing or thread-cutting after sewing, characterized in that the thread-cutting mechanism for starting a sewing or thread-cutting after sewing is fixedly installed on the sewing machine and used for sewing.

[0014] When the thread-cutting mechanism of this application cuts the thread end, under the control of the control system, the needle running in the needle drop position disengages from the needle drop position and rises above the thread-cutting moving blade. The thread-cutting moving blade then moves, causing the thread end to move from the position abutting against the needle drop position to the blade edge of the moving blade. The thread-cutting moving blade continues to move and contacts the thread-cutting fixed blade. The thread-cutting fixed blade contacts the blade edge of the moving blade and cuts the thread end, completing the thread-cutting action of the thread-cutting mechanism. Because the needle drop position and the thread-cutting position of this application are set relatively short, the thread end can be easily cut as short as possible, effectively preventing bird's nest formation. Attached Figure Description

[0015] Figure 1 This is a schematic diagram showing the location of the thread-cutting mechanism on the sewing machine in this application;

[0016] Figure 2 This is an external schematic diagram of a sewing initiation and sewing post-sewing thread cutting mechanism according to this application;

[0017] Figure 3 This is a structural diagram of a sewing initiation and sewing post-sewing thread cutting mechanism according to this application;

[0018] Figure 4 This is a structural diagram of the starting moving blade of a sewing thread cutting mechanism according to this application;

[0019] Figure 5 This is a structural diagram of the starting blade of a second embodiment of a sewing thread cutting mechanism of this application;

[0020] Figure 6 This is a structural diagram of a post-sewing thread-cutting mechanism according to this application;

[0021] Figure 7 yes Figure 6 Enlarged view of point A in the middle.

[0022] The numerical designations of the component names in the above attached diagram are as follows:

[0023] Base 11, needle 12, lower shaft 13;

[0024] 2. Sewing start and thread cutting mechanism; 21. Sewing start and thread cutting driver; 22. Sewing start and thread cutting crank one; 23. Sewing start transmission component; 24. Sewing start fork crank; 241. Fork opening one; 25. Sewing start connecting shaft; 26. Sewing start and thread cutting crank two; 27. Sewing start connecting rod; 28. Sewing start moving knife seat; 29. ​​Sewing start moving knife fixing part.

[0025] 30 for starting the stitch, 31 for the needle dropping position, and 32 for the cutting edge of the moving blade;

[0026] 40mm for starting seam;

[0027] 5. Post-sewing thread cutting mechanism; 51. Post-sewing thread cutting driver; 52. Post-sewing thread cutting crank one; 53. Post-sewing transmission component; 54. Post-sewing fork crank; 541. Fork two; 55. Post-sewing connecting shaft; 56. Post-sewing thread cutting crank two; 57. Post-sewing connecting rod; 58. Post-sewing moving knife seat; 59. Post-sewing moving knife fixing part.

[0028] 60mm for post-sewing cutting, 61mm for thread cutting;

[0029] 70mm fixative after sewing. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1-7 The preferred embodiments of this application are described in detail so that the advantages and features of this application can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the scope of protection of this application. These embodiments are only used to illustrate the present invention and are not intended to limit the present invention.

[0031] The thread-cutting mechanisms of this application are both thread-cutting mechanisms of a sewing machine. Before being installed on the sewing machine, the aforementioned thread-cutting mechanism 2 or thread-cutting mechanism 5 is used to fix the sewing machine and to be used for sewing.

[0032] Example 1

[0033] like Figures 1 to 5 As shown, this application provides a thread-cutting mechanism 2 for preventing bird nest formation. The thread-cutting mechanism 2 is installed and fixed on the base 11 of the sewing machine and is used to cut the thread end, which can effectively prevent the formation of bird nests and improve the sewing quality.

[0034] The sewing start and thread cutting mechanism 2 of this application includes a sewing start and thread cutting driver 21, a sewing start and thread cutting crank 1 22, a sewing start transmission component 23, a sewing start fork-shaped crank 24, a sewing start connecting shaft 25, a sewing start and thread cutting crank 26, a sewing start connecting rod 27, a sewing start moving knife seat 28, a sewing start moving knife fixing part 29, a sewing start moving knife 30, a sewing start fixed knife 40, a needle 12, and a control system, among other components.

[0035] The aforementioned thread-cutting driver 21 is fixed to the base 11. The thread-cutting driver 21 has an output shaft, on which a thread-cutting crank 22 is fixed. A thread-cutting transmission component 23 is located at the other end of the thread-cutting crank 22, within the fork 241 of the thread-cutting fork crank 24. The thread-cutting fork crank 24 fixes a thread-cutting connecting shaft 25. A thread-cutting crank 26 is fixed at the other end of the thread-cutting connecting shaft 25. A thread-cutting connecting rod 27 is hinged to the other end of the thread-cutting crank 26. A thread-cutting moving knife holder 28 is hinged to the other end of the thread-cutting connecting rod 27. The thread-cutting moving knife holder 28 is connected to a thread-cutting moving knife fixing part 29, and a thread-cutting moving knife 30 is fixed to the thread-cutting moving knife fixing part 29. The thread-cutting moving knife holder 28 is fitted onto the lower shaft 13 of the sewing machine, with a clearance fit between the thread-cutting moving knife holder 28 and the lower shaft 13.

[0036] The aforementioned starting sewing knife 30 and starting sewing fixed knife 40 are arranged opposite to each other. The starting sewing knife 30 is provided with a needle drop position 31 and a moving knife edge 32. The needle drop position 31 is used for the temporary running point of the sewing of the needle 12. The moving knife edge 32 and the starting sewing fixed knife 40 are matched to cut the starting sewing thread. The moving knife edge 32 is located to the side and rear of the needle drop position 31. Here, the distance between the needle drop position 31 and the moving knife edge 32 can be set to be short or long. Driven by the thread-cutting driver 21, the thread-cutting blade 30 moves, transferring the thread end from its position against the needle drop position 31 to the blade edge 32. The thread-cutting blade 30 continues to move until it contacts the thread-cutting fixed blade 40, which then easily cuts the thread end upon contact with the blade edge 32. Because the needle drop position and thread-cutting position of the needle 12 are relatively short, the thread-cutting action of the thread-cutting mechanism 2 is completed, preventing excess thread ends from forming a messy, bird's nest-like pattern during thread cutting. This achieves anti-bird's nest stitching and effectively prevents the formation of bird's nests. The blade edge 32 is located to the side and rear of the needle drop position 31.

[0037] Under the control of the control system, the thread-cutting mechanism 2 of this application performs thread-cutting at the start of each stitch, thus effectively preventing the formation of bird nests. Of course, when thread-cutting is required, the needle 12 running in the needle drop position 31 must be disengaged from the needle drop position 31 and higher than the thread-cutting blade 30 before the thread-cutting mechanism 2 can perform the thread-cutting action. The needle drop position 31 of the thread-cutting blade 30 is no longer the temporary sewing location of the needle 12. Driven by the thread-cutting driver 21, the thread-cutting blade 30 moves to a location that does not interfere with the operation of the needle 12, and the sewing machine can continue sewing.

[0038] Example 2

[0039] Combination Figure 5 This embodiment is basically the same as the first embodiment, except that the needle drop position 31 and the moving blade edge 32 provided on the starting sewing knife 30 are overlapped in this embodiment and are the same hole position, and the technical effect is the same as the previous first embodiment.

[0040] Example 3

[0041] like Figures 1 to 3 and Figure 6 Figure 7 As shown, this application discloses a post-sewing thread cutting mechanism 5, which is installed and fixed on the base 11 of a sewing machine and is used to cut the sewing thread ends to achieve the purpose of automatically cutting the sewing thread ends.

[0042] The post-sewing thread cutting mechanism 5 of this application includes components such as a post-sewing thread cutting driver 51, a post-sewing thread cutting crank 52, a post-sewing transmission component 53, a post-sewing fork crank 54, a fork 541, a post-sewing connecting shaft 55, a post-sewing thread cutting crank 56, a post-sewing connecting rod 57, a post-sewing moving knife seat 58, a post-sewing moving knife fixing part 59, a post-sewing moving knife 60, and a post-sewing fixed knife 70.

[0043] The aforementioned post-sewing thread trimming driver 51 is fixed to the base 11. The post-sewing thread trimming driver 51 has an output shaft, on which a post-sewing thread trimming crank 52 is fixed. A post-sewing transmission component 53 is located at the other end of the post-sewing fork crank 54, within a fork 541. The post-sewing fork crank 54 is fixedly connected to a post-sewing connecting shaft 55. A post-sewing thread trimming crank 56 is fixed at the other end of the post-sewing connecting shaft 55. A post-sewing connecting rod 57 is hinged to the other end of the post-sewing connecting rod 57. A post-sewing moving knife holder 58 is hinged to the other end of the post-sewing moving knife holder 58, which is connected to a post-sewing moving knife fixing part 59. A post-sewing moving knife 60 is fixed to the post-sewing moving knife fixing part 59. The post-sewing moving knife holder 58 is sleeved on the lower shaft 13, with a clearance fit between the post-sewing moving knife holder 58 and the lower shaft 13.

[0044] The aforementioned post-sewing moving blade 60 has a thread-cutting edge 61, and the post-sewing moving blade 60 is positioned opposite to the post-sewing fixed blade 70. When sewing is finished, after the needle 12 protrudes above the needle plate, under the control of the control system, the post-sewing moving blade 60 moves towards the post-sewing fixed blade 70, and the thread end is cut between the post-sewing moving blade 60 and the thread-cutting edge 61, realizing automatic post-sewing thread cutting. This results in shorter residual thread ends on the sewing fabric after sewing, significantly improving the standardization of sewing processes and greatly reducing labor intensity.

[0045] The above description is only one of the preferred embodiments of this application and is not intended to limit the present invention, nor does it limit the scope of patent implementation of this application. Any equivalent structural or procedural transformations made using the shape, structure, and principle described in the specification and drawings of this application, or any direct or indirect application in other related technical fields; any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention are all included within the scope of patent protection of this application.

Claims

1. A sewing thread cutting mechanism, comprising a sewing moving blade (30), a sewing stationary blade (40), and a control system, characterized in that, It also has a thread-cutting driver (21) and a needle (12). The thread-cutting driver (21) is fixedly installed on the base (11) of the sewing machine. The thread-cutting knife (30) is provided with a needle drop position (31) and a moving blade edge (32). When the thread-cutting action is to be performed, under the control of the control system, the needle (12) running in the needle drop position (31) leaves the needle drop position (31) and is higher than the thread-cutting knife (30). The thread-cutting knife (30) moves, so that the thread-cutting head moves from the position against the needle drop position (31) to the moving blade edge (32). The thread-cutting knife (30) continues to move and contacts the thread-cutting fixed knife (40). The thread-cutting fixed knife (40) contacts the moving blade edge (32) and cuts the thread-cutting head, thus completing the thread-cutting action.

2. The seam-starting and thread-cutting mechanism according to claim 1, characterized in that, The moving blade edge (32) is located to the side and rear of the needle drop position (31).

3. The sewing and thread-cutting mechanism according to claim 1, characterized in that, The needle drop position (31) and the moving blade edge (32) overlap and are the same hole position.

4. The sewing and thread-cutting mechanism according to claim 1, characterized in that, The starting sewing knife (30) and the starting sewing fixed knife (40) are arranged opposite to each other.

5. The seam-starting and thread-cutting mechanism according to claim 1, characterized in that, The aforementioned thread-cutting driver (21) has an output shaft, on which a thread-cutting crank (22) is fixed. At the other end of the thread-cutting crank (22) is a thread-cutting transmission component (23). The thread-cutting transmission component (23) is located in the fork (241) of the thread-cutting fork crank (24). The thread-cutting fork crank (24) fixes the thread-cutting connecting shaft (25). At the other end of the thread-cutting connecting shaft (25), a thread-cutting crank (26) is fixed. At the other end of the thread-cutting crank (26), a thread-cutting connecting rod (27) is hinged. At the other end of the thread-cutting connecting rod (27), a thread-cutting moving knife seat (28) is hinged. The thread-cutting moving knife seat (28) is connected to the thread-cutting moving knife fixing part (29). A thread-cutting moving knife (30) is fixed on the thread-cutting moving knife fixing part (29).

6. The seam-starting and thread-cutting mechanism according to claim 5, characterized in that, The sewing starter knife holder (28) is fitted onto the lower shaft (13) of the sewing machine, and the sewing starter knife holder (28) and the lower shaft (13) are in clearance fit.

7. A post-sewing thread-cutting mechanism, comprising a post-sewing moving blade (60), a post-sewing fixed blade (70), and a thread-cutting driver (51), characterized in that, It also has a post-sewing thread cutting driver (51), which is fixed on the base (11). The post-sewing moving knife (60) has a thread cutting edge (61). The post-sewing moving knife (60) and the post-sewing fixed knife (70) are arranged opposite to each other. Under the control of the control system, the post-sewing moving knife (60) moves towards the post-sewing fixed knife (70), and the post-sewing thread end is cut between the post-sewing moving knife (60) and the thread cutting edge (61), thereby realizing automatic post-sewing thread cutting.

8. A thread-cutting mechanism after sewing according to claim 7, characterized in that, The post-sewing thread cutting driver (51) has an output shaft, on which a post-sewing thread cutting crank (52) is fixed. At the other end of the post-sewing thread cutting crank (52) is a post-sewing transmission component (53). The post-sewing transmission component (53) is located in the fork (541) of the post-sewing fork crank (54). The post-sewing fork crank (54) is fixedly connected to the post-sewing connecting shaft (55). At the other end of the post-sewing connecting shaft (55), a post-sewing thread cutting crank (56) is fixed. At the other end of the post-sewing thread cutting crank (56), a post-sewing connecting rod (57) is hinged. At the other end of the post-sewing connecting rod (57), a post-sewing moving knife seat (58) is hinged. The post-sewing moving knife seat (58) is connected to the post-sewing moving knife fixing part (59). A post-sewing moving knife (60) is fixed on the post-sewing moving knife fixing part (59).

9. A thread-cutting mechanism after sewing according to claim 8, characterized in that, The post-sewing moving knife holder (58) is sleeved on the lower shaft (13), and the post-sewing moving knife holder (58) and the lower shaft (13) are in clearance fit.

10. A sewing machine comprising the thread-cutting mechanism or the thread-cutting mechanism according to any one of claims 1 to 9, characterized in that, The aforementioned thread-cutting mechanism or thread-cutting mechanism is used to be fixedly installed on the sewing machine and used for sewing.

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