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CN-118087170-B - Double-cutter thread cutting mechanism of sewing machine and sewing machine

CN118087170BCN 118087170 BCN118087170 BCN 118087170BCN-118087170-B

Abstract

The invention relates to a double-cutter thread cutting mechanism of a sewing machine, the double-cutter thread cutting mechanism comprises a first cutter frame, a first thread cutting cutter, a second cutter frame, a second thread cutting cutter and a thread cutting driving mechanism, the sewing machine further comprises a bottom thread catching member, the bottom thread catching member comprises a mounting section and an arc catching piece, one end of the arc catching piece, which is connected with the mounting section, is a side B end, the other end of the arc catching piece, which is towards the second thread cutting cutter, is a side B end, a first catching part is arranged on the first thread cutting cutter, a second catching part is arranged on the outer cambered surface of the arc catching piece, the first catching part is abutted against the second catching part in the initial position, a driving pressing block is fixed on the first cutter frame or the first thread cutting cutter, the second thread cutting cutter and the first thread cutting cutter are rotated to be abutted, the driving pressing block presses the arc catching piece to bend or deflect to be separated from the first thread cutting cutter, a thread cutting hook stretches between the first catching part and the second catching part, and the arc catching piece resets when the driving pressing block is not pressed by the driving pressing block.

Inventors

  • TAN XINMIN
  • LI BAOQING
  • ZHANG PENG
  • GUAN JIANPING
  • HONG ZHIMIN

Assignees

  • 杰克科技股份有限公司

Dates

Publication Date
20260505
Application Date
20221118

Claims (14)

  1. 1. The utility model provides a sewing machine's double knives thread cutting mechanism for set up in sewing machine's rotating shuttle subassembly (6) department and cut the line, double knives thread cutting mechanism includes first knife rest (4), fixes first thread cutting sword (2) on first knife rest (4), second knife rest (5), fixes second thread cutting sword (3) on second knife rest (5), and cuts line actuating mechanism, first thread cutting sword (2) and second thread cutting sword (3) are located rotating shuttle subassembly (6) periphery side department, cut line actuating mechanism drive first knife rest (4) and second knife rest (5) rotation for first thread cutting sword (2) and second thread cutting sword (3) rotate around rotating shuttle subassembly (6) axis to be close to or separate mutually, be equipped with on second thread cutting sword (3) and be used for driving the wire cutting hook (302) of bottom line towards first thread cutting sword (2) motion, its characterized in that: the double-cutter thread cutting mechanism further comprises a bottom thread capturing piece (1), the bottom thread capturing piece (1) comprises a mounting section (102) which is fixedly mounted and an arc capturing piece (101) which is connected with the mounting section (102), the arc capturing piece (101) is arranged along the peripheral side of the rotating shuttle assembly (6) and is positioned in the minimum rotation range of the first thread cutting cutter (2), and one end, which is connected with the mounting section (102), of the arc capturing piece (101) is a side B end (104), the other end facing the second thread cutter (3) is an A side end (105), a first catching part (201) is arranged on the side surface of the first thread cutter (2) facing the rotating shuttle assembly (6), a second catching part (103) is arranged on the outer cambered surface of the arc catching piece (101), the first catching part (201) is abutted against the second catching part (103) when the first thread cutter (2) does not cut threads, a driving press block (402) is further fixed on the first cutter rest (4) or the first thread cutter (2), the driving press block (402) is positioned on the outer cambered surface side of the arc catching piece (101), when the thread cutter (2) and the first thread cutter (2) are both rotated to be abutted, the driving press block (402) moves on the outer cambered surface of the arc catching piece (101) and presses the arc catching piece (101) to bend or deflect to be separated from the first thread cutter (2), a thread hook (302) stretches into the position between the first catching part (103) and the second thread cutter (101) and is capable of pressing the second thread cutter (101) after the first thread cutter (101) is reset, and the first thread cutter (101) can be pressed and the thread cutter (2) is not caught after the first thread cutter (101) is reset, the first catching part (201) is contacted with the second catching part (103) again to catch the bottom thread head.
  2. 2. The double-blade thread cutting mechanism as set forth in claim 1, wherein the distance between the B-side end (104) of the arc-shaped catching piece (101) and the rotating shuttle assembly (6) is smaller than the distance between the A-side end (105) and the rotating shuttle assembly (6).
  3. 3. The double-blade thread cutting mechanism of claim 1, wherein the arc-shaped capturing piece (101) is provided with a protruding portion (107), and the driving pressing block (402) can move to the protruding portion (107) on the arc-shaped capturing piece (101) when cutting threads.
  4. 4. The double-blade wire cutting mechanism as set forth in claim 1, wherein the driving press block (402) has a smooth working surface for contacting with the outer arc surface of the arc-shaped catching piece (101).
  5. 5. The double-blade thread cutting mechanism according to claim 1, wherein the mounting section (102) of the bobbin thread catching member (1) is fixedly connected with the arc catching piece (101), and the arc catching piece (101) itself can be bent and deformed.
  6. 6. The double-blade thread cutting mechanism as set forth in claim 1, wherein the mounting section (102) of the bobbin thread catching member (1) is rotatably connected with the arc catching piece (101), and an elastic reset structure is provided between the arc catching piece (101) and the mounting section (102), and the elastic reset structure is in an elastic energy storage state and provides an elastic force for resetting the arc catching piece (101) when the arc catching piece (101) deflects towards the rotating shuttle assembly (6).
  7. 7. The double-blade thread cutting mechanism as set forth in claim 1, wherein the A-side end (105) of the arc-shaped catching piece (101) is chamfered to form an anti-collision notch (106).
  8. 8. The double-blade thread cutting mechanism according to claim 1, wherein the second thread cutting blade (3) is in an arc shape and is coaxial with the rotating shuttle assembly (6).
  9. 9. The double-blade thread cutting mechanism according to claim 1, wherein a first blade edge is arranged on one side, facing the second thread cutting blade (3), of the first thread cutting blade (2), a bulge (301) is arranged on the second thread cutting blade (3), a through hole is formed in the bulge (301), the bulge (301) forms a second blade edge at the edge of the through hole, and when thread cutting is performed, the first thread cutting blade (2) and the second thread cutting blade (3) are close to the first blade edge and the second blade edge to be meshed.
  10. 10. The double-blade thread cutting mechanism according to claim 1, further comprising an adjusting screw, wherein the mounting section (102) of the bobbin thread capturing piece (1) is of a flat plate structure, an tightness adjusting hole is formed in one side, close to the arc capturing piece (101), of the mounting section (102), a component for fixedly mounting the bobbin thread capturing piece (1) in the sewing machine is a capturing piece mounting base, the adjusting screw penetrates through the tightness adjusting hole and is screwed into the capturing piece mounting base, an adjusting gap is formed between the tightness adjusting hole and the capturing piece mounting base, and when the adjusting screw is screwed or unscrewed, the mounting section (102) can deform and change the contact pressure between the second capturing portion (103) and the first capturing portion (201).
  11. 11. The double-blade thread cutting mechanism according to claim 1, wherein the thread cutting hook (302) of the second thread cutting blade (3) is composed of a thread hooking oblique edge (305) and a thread hooking flange (306), the thread hooking oblique edge (305) obliquely extends rightward from the left side of the second thread cutting blade (3), the thread hooking flange (306) is arranged on the right side of the thread hooking oblique edge (305), the thread hooking flange (306) is obliquely arranged leftward and rightward, one end close to the bottom thread capturing piece (1) is located on the left side, one end far away from the bottom thread capturing piece (1) is located on the right side, and one end of the thread hooking flange (306) close to the bottom thread capturing piece (1) is located on the right side of the second capturing portion (103).
  12. 12. The double-blade thread cutting mechanism of claim 11, wherein the inclination angle of the thread hooking flange relative to the front-rear direction is 2-4 degrees.
  13. 13. The double-blade thread cutting mechanism as set forth in claim 12, wherein the hook flange is inclined at an angle of 3 ° with respect to the front-rear direction.
  14. 14. A sewing machine comprising a rotating shuttle mechanism, and further comprising a double-knife thread cutting mechanism as claimed in any one of claims 1 to 13, wherein the double-knife thread cutting mechanism is arranged at a rotating shuttle assembly (6) in the rotating shuttle mechanism to cut threads.

Description

Double-cutter thread cutting mechanism of sewing machine and sewing machine Technical Field The invention relates to the field of sewing equipment, in particular to a double-cutter thread cutting mechanism of a sewing machine and the sewing machine. Background After trimming, capturing the thread end of the bottom thread, and greatly improving the success rate of the sewing machine for starting the sewing belt bottom thread. However, for many years, a lockstitch sewing machine adopting a circular knife thread cutting mechanism has no effective way to achieve the capturing of the bottom thread in a forbidden zone of the bottom thread capturing. The flat seam circular knife thread cutting mechanism is also divided into a single knife thread cutting mechanism and a double knife thread cutting mechanism. The single-blade thread cutting mechanism is characterized in that a fixed blade arranged at the rear side of the needle is a fixed thread cutting blade, and a movable blade is a movable thread cutting blade. When cutting the thread, the movable knife rotates towards the fixed knife, and the thread cutting is completed at the side of the needle close to the operator (also called the front side of the sewing machine). The problem is that the sharp stationary knife cutting edge is slightly close to the movable area of the needle and the suture, so that the breakage rate of the sewing machine in the sewing process is increased, and the stationary knife cannot be arranged below the needle to achieve the purpose of shorter thread end on cloth after thread cutting. The double-cutter thread cutting mechanism adopts a pair of thread cutting cutters which move in two directions, so that the thread can be cut under the needle, and the thread cutting cutters can be far away from the movable area of the needle and the suture after the thread cutting is completed. The method has the advantage that the residual thread ends on the fabric after thread cutting are shorter than the thread ends of the single-blade thread cutting mechanism, and the method meets the production and quality requirements of high-grade clothing, so that the method is approved by the market. Therefore, the double-cutter thread cutting mechanism capable of capturing the bottom thread is provided, and the problem to be solved by the existing sewing machine is urgent. Disclosure of Invention In view of the above-mentioned drawbacks of the prior art, the present invention is to provide a double-knife thread cutting mechanism of a sewing machine, and a sewing machine, which can stabilize the position of a bottom thread end after thread cutting, ensure that the next seam can be smoothly lifted, solve the problem of difficult seam lifting of the existing double-knife thread cutting mechanism, and have extremely simple structure, and only need to modify the existing double-knife thread cutting mechanism. In order to achieve the above-mentioned purpose, the present invention provides a double-knife thread cutting mechanism of a sewing machine, which is used for cutting threads at a rotating shuttle assembly of the sewing machine, the double-knife thread cutting mechanism comprises a first knife rest, a first thread cutting knife fixed on the first knife rest, a second thread cutting knife fixed on the second knife rest, and a thread cutting driving mechanism, wherein the first thread cutting knife and the second thread cutting knife are positioned at the peripheral side of the rotating shuttle assembly, the thread cutting driving mechanism drives the first knife rest and the second thread cutting knife to rotate, so that the first thread cutting knife and the second thread cutting knife rotate to be close to or separate from each other around the axis of the rotating shuttle assembly, the second thread cutting knife is provided with a thread cutting hook for driving a bottom thread to move towards the first thread cutting knife, the bottom thread capturing member comprises a fixedly mounted mounting section, and an arc capturing blade connected with the mounting section, the arc capturing blade is arranged along the peripheral side of the rotating shuttle assembly and positioned at the first cambered side, the capturing section is provided with a first cambered capturing section, and the first cambered capturing section is arranged at the second cambered capturing section is arranged at the first cambered side, and the capturing section is provided with a first cambered capturing section, and the first cambered capturing section is arranged at the first cambered capturing section is towards the capturing section B; the first knife rest or the first thread cutting knife is also fixed with a driving pressing block, the driving pressing block is positioned at the outer cambered surface side of the arc-shaped capturing piece, when the thread is cut, the second thread cutting knife and the first thread cutting knife are rotated to be close to each other, the driving