Sewing machine and thread trimming mechanism and double action knife assembly

Abstract

The utility model belongs to sewing machine technical field especially relates to a sewing machine and cut thread mechanism and double moving knife subassembly, including first moving knife subassembly and second moving knife subassembly, first moving knife subassembly is used for hooking sewing thread, second moving knife subassembly cooperates first moving knife subassembly and cuts off sewing thread, second moving knife sets up in first moving knife's top, and the front end of second moving knife is in abutment on the upper surface of first moving knife, and the front end part of second moving knife is provided with second cutting edge, when second moving knife slides on the surface of first moving knife to the set position, second cutting edge cooperates first cutting edge and cuts off sewing thread, in the case where one moving knife retreats and hooks thread, the other moving knife advances and cooperates and cuts thread, and two moving knives complete cutting thread together, and the position of cutting thread is more close to needle, realizes shorter thread end effect.

Description

Technical Field

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

[0002] A sewing machine mainly consists of a base (i.e., the machine casing and base plate), a needle bar mechanism, a feeding mechanism, a thread hooking mechanism, a presser foot mechanism, a thread cutting mechanism, and accessories. Through the reasonable coordination of the movements of each mechanism, it works in a cycle to sew the fabric together.

[0003] During the initial and final stages of sewing, long thread ends remain on the fabric surface. These starting thread ends form bird's nest-like patterns on the sewn garment, affecting its overall quality. To ensure garment quality, these thread ends must be trimmed manually, increasing labor intensity and impacting production efficiency.

[0004] To improve sewing efficiency, sewing equipment typically employs automatic thread-cutting mechanisms. These mechanisms not only ensure smooth sewing but also reduce loose threads in garments, improving the efficiency of subsequent finishing. CN202322683791.X discloses a single-action anti-bird's nest thread-cutting mechanism and sewing machine. This technical solution can cut excessively long portions of the sewing thread during the initial sewing stage and can also cut the thread after the sewing process is completed.

[0005] In practical applications, the existing technical solution still doesn't achieve ideal thread lengths on the fabric surface. For ordinary clothing, the thread length is generally sufficient to eliminate the need for secondary manual trimming. However, for some high-end garments, the thread length remaining on the fabric is still quite noticeable, requiring manual trimming. Therefore, the applicant is further developing and seeking a new technical solution to achieve even shorter thread trimming results. Utility Model Content

[0006] The purpose of this invention is to provide a sewing machine, thread cutting device, and double-blade assembly that can achieve shorter thread ends when cutting threads.

[0007] The purpose of this utility model is achieved as follows:

[0008] The double-moving-blade assembly of the sewing machine thread-cutting mechanism includes a first moving-blade assembly and a second moving-blade assembly; the first moving-blade assembly is used to hook the sewing thread, and the second moving-blade assembly cooperates with the first moving-blade assembly to cut the sewing thread;

[0009] The first moving blade assembly includes a first moving blade holder and a first moving blade; a first ring portion is provided in the middle of the first moving blade holder, and the first ring portion is rotatably mounted on the outside of the rotary shuttle mechanism; a first driving portion is provided on one side of the first ring portion, and the first moving blade is provided on the other side; a first cutting edge is provided at the tip of the first moving blade.

[0010] The second moving blade assembly includes a second moving blade holder and a second moving blade; a second ring portion is provided in the middle of the second moving blade holder, and the second ring portion is used to rotatably mount on the outside of the rotary hook mechanism; a second drive portion is provided on one side of the second ring portion, and the second moving blade is provided on the other side;

[0011] The second moving blade is positioned above the first moving blade, with its front end resting against the upper surface of the first moving blade. The front end of the second moving blade is provided with a second cutting edge. When the second moving blade slides to a set position on the surface of the first moving blade, the second cutting edge cooperates with the first cutting edge to cut the sewing thread.

[0012] Preferably, the first moving blade has a front hole groove and a hook groove, which are arranged along the rotation direction of the first moving blade; the front hole groove is located at the tip of the first moving blade, and the first cutting edge is provided at the front edge of the front hole groove; the hook groove is located in the middle of the first moving blade, and the hook groove has an opening for hooking the thread; a receiving groove for accommodating sewing thread is provided between the front hole groove and the hook groove.

[0013] Preferably, the first ring portion and the second ring portion are arranged side by side, or the first ring portion and the second ring portion are fitted together inside and outside of each other;

[0014] The first and second annular portions are arranged on the same axis.

[0015] Preferably, the first driving unit and the second driving unit are located on the same side;

[0016] The front hole slot and / or hook slot allow the sewing machine needle to pass through.

[0017] The thread-cutting mechanism of the sewing machine includes the aforementioned double-moving blade assembly; it also includes:

[0018] A first transmission assembly is used to drive a first drive unit of the first ring portion;

[0019] The second transmission assembly is used to drive the second drive unit of the second ring portion;

[0020] At least one drive component is used to drive the first transmission component and / or the second transmission component.

[0021] Preferably, the drive component is provided as one unit, which is a motor, and the motor shaft of the motor drives the first transmission component and the second transmission component;

[0022] The first transmission assembly includes a first crank and a first connecting rod; one end of the first crank is driven by the motor, the other end of the first crank is hinged to one end of the first connecting rod, and the other end of the first connecting rod is hinged to the first drive part of the first moving tool holder;

[0023] The second transmission assembly includes a drive cam, a second drive crank, and a second connecting rod; one end of the second connecting rod is hinged to the second drive part of the second moving tool holder, and the other end of the second connecting rod is hinged to one end of the second drive crank, which is rotatably mounted on the frame; the other end of the second drive crank is provided with a movable or deformable abutment; the drive cam is driven by the motor, and one side of the drive cam abuts against the abutment; when the drive cam applies force to the abutment from a first predetermined direction, the abutment moves or deforms and counteracts the transmission of the drive cam; when the drive cam applies force to the abutment from a second predetermined direction, the abutment is linked to the second drive crank.

[0024] Preferably, the lower part of the second drive crank is provided with a guide groove, and the abutment part includes a movable rod disposed in the guide groove. An elastic component is disposed in the guide groove, and the elastic component is used for resetting the movable rod. When the drive cam rotates from the first set direction and presses the movable rod, the movable rod retracts into the guide groove. When the drive cam rotates from the second set direction and presses the movable rod, the movable rod drives the second drive crank to rotate.

[0025] Preferably, when the drive cam rotates in the first predetermined direction, the drive cam abuts against the end of the moving rod; when the drive cam rotates in the second predetermined direction, the drive cam abuts against the side of the moving rod.

[0026] A sewing machine including the aforementioned thread-cutting mechanism.

[0027] The outstanding and beneficial technical effects of this utility model compared to the prior art are:

[0028] This patented technology uses two moving blades to cut the thread. While one blade moves backward and hooks the thread, the other blade moves forward and cuts the thread. The thread cutting, completed by the two blades together, is closer to the needle, resulting in a shorter thread end.

[0029] Both moving blades of this patent are mounted on the rotary hook sleeve and are set on the same axis; their transmission accuracy is high and it is also conducive to the operation of the background program.

[0030] This patent allows for the separate control of two moving blades by a single power source, achieving further optimization in terms of structure and cost. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the assembly state of the first moving blade assembly and the second moving blade assembly of this utility model.

[0032] Figure 2 This is a schematic diagram showing the disassembled state of the first moving blade assembly and the second moving blade assembly of this utility model.

[0033] Figure 3 This is a schematic diagram of the installation of the first moving blade assembly and the second moving blade assembly of this utility model.

[0034] Figure 4 This is a schematic diagram showing the cooperation between the first moving blade and the second moving blade of this utility model.

[0035] Figure 5 This is one of the transmission diagrams of the wire-cutting mechanism of this utility model.

[0036] Figure 6 This is the second transmission schematic diagram of the wire-cutting mechanism of this utility model.

[0037] Figure 7 This is a schematic diagram of the second drive crank of this utility model.

[0038] Figure 8 This is a schematic diagram of the wire-cutting mechanism of this utility model mounted on the frame.

[0039] Figure 9 yes Figure 7 Enlarged view of point A.

[0040] Figure 10 This is a schematic diagram of the working angle of the drive component of this utility model.

[0041] Figure 11 This is a schematic diagram of the first and second moving blades working together in another embodiment.

[0042] Figure 12 This is one of the transmission schematic diagrams of another embodiment.

[0043] Figure 13 This is another schematic diagram of the transmission in another embodiment. Detailed Implementation

[0044] The present invention will be further described below with reference to specific embodiments:

[0045] Example 1, as Figure 1-10As shown, the double-moving-blade assembly of the sewing machine thread-cutting mechanism includes a first moving-blade assembly 10 and a second moving-blade assembly 20; both the first moving-blade assembly 10 and the second moving-blade assembly 20 are rotatably mounted on the outside of the adapted rotary hook mechanism; the first moving-blade assembly is used to hook the sewing thread, and the second moving-blade assembly cooperates with the first moving-blade assembly to cut the sewing thread;

[0046] The first moving blade assembly 10 includes a first moving blade holder 11 and a first moving blade 12; a first annular portion 111 is provided in the middle of the first moving blade holder, and the first annular portion 111 is rotatably mounted on the outside of the rotary shuttle mechanism 30; a first driving portion 112 is provided on one side of the first annular portion 111, and a first moving blade mounting portion 113 is provided on the other side, the first moving blade mounting portion 113 is a component that extends along the axial direction of the first annular portion 111, and the first moving blade 12 is mounted on the first moving blade mounting portion 113; a first cutting edge 121 is provided at the tip of the first moving blade;

[0047] The second moving blade assembly 20 includes a second moving blade holder 21 and a second moving blade 22; a second ring portion 211 is provided in the middle of the second moving blade holder 21, which is used to rotatably mount on the outside of the rotary hook mechanism; a second drive portion 212 is provided on one side of the second ring portion, and a second moving blade mounting portion 213 is provided on the other side, which is a component that extends along the axial direction of the second ring portion 211, and the second moving blade 22 is mounted on the second moving blade mounting portion 213;

[0048] The second moving blade 22 is positioned above the first moving blade 12, with its front end resting against the upper surface of the first moving blade 12. The front end of the second moving blade has a second cutting edge 221. When the second moving blade 22 slides to a set position on the surface of the first moving blade 12, the second cutting edge 221 cooperates with the first cutting edge 121 to cut the sewing thread. Specifically, both the first ring portion 111 and the second ring portion 211 are fitted onto the front end of the rotary shuttle sleeve 301 of the rotary shuttle mechanism 30. A ring portion 302 is provided at the front end of the rotary shuttle sleeve 301, and the first ring portion 111 and the second ring portion 211 are fitted adjacently onto the ring portion 302.

[0049] The first moving blade 12 and the second moving blade 22 are both located on the same side of the needle position to enable the first moving blade to retract and the second moving blade to advance, thereby cutting the thread. During the thread cutting process, the first moving blade 12 first rotates in a first direction to a set position, and then rotates in a second direction, driving the sewing thread. While the first moving blade rotates in the second direction, the second moving blade 22 rotates in the first direction. The second moving blade 22 slides on the surface of the first moving blade 12, and the second cutting edge 221 cooperates with the first cutting edge 121 to cut the sewing thread. The first direction of rotation is counterclockwise, and the second direction of rotation is clockwise; or, the first direction of rotation is clockwise, and the second direction of rotation is counterclockwise. Preferably, the first moving blade 12 is provided with a front hole groove 122 and a hook groove 123, which are arranged along the rotation direction of the first moving blade 12; the front hole groove 122 is located at the tip of the first moving blade 12, and the first cutting edge 121 is provided at the front edge of the front hole groove 122; the hook groove 123 is located in the middle of the first moving blade, and the hook groove 123 is provided with an opening 1231 for hooking the thread; a receiving groove 124 for receiving sewing thread is provided between the front hole groove and the hook groove.

[0050] Preferably, the first ring portion 111 and the second ring portion 211 are arranged side by side, or the first ring portion 111 and the second ring portion 211 are fitted together inside and outside.

[0051] The first annular portion 111 and the second annular portion 211 are arranged on the same axis. This ensures a tight fit between the first moving cutter and the second moving cutter.

[0052] Preferably, the first drive unit 112 and the second drive unit 212 are both located on the same side; the first moving blade 12 and the second moving blade 22 are both located on the same side. When both moving blades are located on the same side, a coordinated thread-cutting operation can be achieved, with one blade moving forward and the other moving backward. If the two moving blades are located on different sides, only the thread-cutting action at the end of the sewing stage can be achieved, and the thread-cutting action at the beginning of the sewing stage cannot be achieved. When the two moving blades are located on different sides, the two blades move forward or backward synchronously. Even if a front slot 122 is provided on one of the blades, the other moving blade will move to the position of the needle before the front slot 122 moves to the position of the needle, making it impossible to cut the thread.

[0053] The front slot 122 and / or the hook slot 123 allow the sewing machine needle 90 to pass through. This design corresponds to the down position of the needle 90, and is applicable to both positions.

[0054] The thread-cutting mechanism of the sewing machine includes the aforementioned double-moving blade assembly; it also includes:

[0055] The first transmission assembly 40 is used to drive the first drive unit 112 of the first ring portion;

[0056] The second transmission assembly 50 is used to drive the second drive unit 212 of the second ring portion;

[0057] At least one drive component 60 is provided to drive the first transmission component 40 and / or the second transmission component 50. When there is only one drive component 60, the cost is lower and the electrical control is simpler. It is preferable that the first transmission component 40 and the second transmission component 50 are located on two different sides of the drive component, which allows for easier configuration of the transmission structure, enabling one component to swing upwards for tool feed and the other to swing downwards for tool retraction.

[0058] Preferably, the driving component is a motor 101, and the motor shaft drives the first transmission component 40 and the second transmission component 50. The motor can be configured as a dual-shaft motor, and the other end of its motor shaft is used to drive another set of mechanisms 102, such as a presser foot lifting mechanism or a needle pitch adjustment mechanism. The technical solution for how the two sets of mechanisms share a motor is already relatively mature, and will not be described in detail in this application.

[0059] The first transmission assembly includes a first crank 41 and a first connecting rod 42; one end of the first crank 41 is fixedly mounted on a tangential crank shaft 103, which is driven by the motor shaft; the other end of the first crank is hinged to one end of the first connecting rod 42, and the other end of the first connecting rod is hinged to the first drive part 112 of the first moving tool holder; a first spring 48 is mounted on the first crank 41, which gives the first transmission assembly a tendency to maintain its reset position.

[0060] The second transmission assembly 50 includes an intermittent motion mechanism 59; during the rotation of the first moving blade 12 in the first direction, the intermittent motion mechanism 59 isolates the power transmission between the drive assembly and the second moving blade assembly 20; during the rotation of the first moving blade 12 in the second direction, the intermittent motion mechanism 59 transmits the power of the drive assembly to the second moving blade assembly 20. Specifically, the second transmission assembly includes a drive cam 51, a second drive crank 52, and a second connecting rod 53; the second drive crank 52 is rotatably mounted on the frame via a hinge point 521; one end of the second connecting rod 52 is hinged to the second drive part 212 of the second moving blade holder, and the other end of the second connecting rod 53 is hinged to one end of the second drive crank 52, with the second drive crank rotatably mounted on the frame;

[0061] An intermittent motion mechanism 59 is provided between the second drive crank 52 and the drive cam 51. The intermittent motion mechanism 59 includes a movable or deformable abutment 54 disposed at the other end of the second drive crank 52. The drive cam 51 is fixedly mounted on the tangential crankshaft 103, and the drive cam 51 and the first crank 41 move synchronously. One side of the drive cam 51 abuts against the abutment 54. When the drive cam applies force to the abutment 54 from a first set direction (the first set direction of the drive cam is counterclockwise rotation, corresponding to the process of the first moving blade 12 rotating in the first direction), the abutment moves or deforms and counteracts the transmission of the drive cam 51. When the drive cam applies force to the abutment from a second set direction (the second set direction of the drive cam is clockwise rotation, corresponding to the process of the first moving blade 12 rotating in the second direction), the abutment 54 is linked to the second drive crank 52. Without the intermittent motion mechanism 59, when the first moving blade assembly moves in the first direction, the second moving blade assembly will also move in the first direction. The second moving blade assembly will interfere with the first moving blade assembly's action of hooking the sewing thread, resulting in thread cutting failure.

[0062] Preferably, the lower part of the second drive crank 52 is provided with a guide groove 522, and the abutment part 54 includes a movable rod 545 disposed in the guide groove 522. An elastic member 541 is disposed in the guide groove 522, and the elastic member 541 is used for the reset of the movable rod 545. When the drive cam 51 rotates from the first set direction and presses the movable rod, the drive cam abuts against the end 544 of the movable rod, and the movable rod 545 retracts into the guide groove 522 and isolates the power transmission. When the drive cam rotates from the second set direction and presses the movable rod 545, the drive cam abuts against the side 543 of the movable rod, and the movable rod drives the second drive crank 52 to rotate. An adjusting nut 542 is installed at the rear end of the movable rod 545, and the elastic force of the elastic member 541 can be controlled by rotating the adjusting nut 542. A second shock-absorbing pad 523 is provided on one side of the second drive crank 52, and the second shock-absorbing pad 523 abuts against the bracket 524, which is fixed to the frame 100. A second spring 58 is installed on the second drive crank 52, allowing the second drive crank 52 to quickly return to its original position after the moving rod 545 disengages from the surface of the drive cam 51. The elastic force of the second spring 58 is weak and does not hinder the retraction of the moving rod 545.

[0063] A sewing machine including the aforementioned thread-cutting mechanism.

[0064] The coordination between the first and second moving blades in this embodiment is as follows: Figure 4As shown; in this embodiment, the front hole groove 122 of the first moving blade 12 is used as the needle insertion position to perform the thread cutting action in the starting stage of sewing; the hook groove 123 of the first moving blade 12 is used to perform the thread cutting action in the ending stage of sewing.

[0065] The thread-cutting mechanism's thread-cutting method during the initial sewing stage, such as... Figure 9 As shown:

[0066] (1) Position a0 is the initial position of the driving component;

[0067] (2) The drive assembly rotates clockwise from position a0 to position a1, the first moving blade 12 moves forward, and the second moving blade 22 remains stationary; the corresponding transmission process is as follows: the drive assembly drives the first crank 41, the first connecting rod 42, and the first moving blade assembly 10, and the first moving blade 12 moves towards the needle; during this process, the front slot 122 of the first moving blade 12 has passed the needle position; the drive assembly simultaneously drives the drive cam 51, the wheel surface of the drive cam 51 abuts against the end 544 of the moving rod and compresses the moving rod; at position a1, the drive cam has rotated past the change node, and the wheel surface of the drive cam abuts against the side 543 of the moving rod; such as Figure 5 and 6 As shown, before the change node, the drive cam cannot drive the second crank 52 by rotating counterclockwise or clockwise, but after the change node, the drive cam can drive the second crank 52 by rotating counterclockwise.

[0068] (3) The drive assembly rotates counterclockwise from position a1 to position a2, and the first moving blade 12 retracts to the front slot 122, which is below the needle. The controller then controls the needle to pass through the front slot 122 downwards, then exit the front slot 122 upwards and be raised to a suitable position (this suitable position must ensure that the movement of the first moving blade 12 is not disturbed, generally the needle is raised above the needle plate). At this time, the surface line on the needle will remain in the front slot 122.

[0069] (4) The drive assembly rotates counterclockwise from position a2 to position a3. At this time, the first moving blade 12 and the second moving blade 22 move towards each other. The front slot 122 of the first moving blade 12 drives the end of the face thread toward the direction of the second moving blade. The second cutting edge 221 of the second moving blade 22 slides toward the front slot 122. At position a3, the second cutting edge 221 cooperates with the first cutting edge 121 to cut the face thread. The corresponding transmission process is as follows: the tangent crank shaft 103 rotates counterclockwise, and the first crank 41 drives the first moving blade to move backward. The wheel surface of the drive cam abuts against the side 543 of the moving rod, driving the second moving blade to move forward.

[0070] (5) The drive assembly rotates counterclockwise from position a3 to position a4, and the first moving blade 12 and the second moving blade 22 continue to move towards each other; at position a4, after the outermost wheel surface of the drive cam passes the side 543 of the moving rod, the second moving blade 22 moves to the limit position and is reset under the action of the spring.

[0071] (6) The drive component rotates counterclockwise from position a4 to position a0, and the first moving blade 12 also completes its reset.

[0072] The thread cutting mechanism uses a twisted combination of top and bottom threads in the final sewing stage; the transmission process in the final sewing stage is the same as that in the starting sewing stage, so it will not be elaborated further.

[0073] The thread-cutting mechanism's thread-cutting method at the end of the sewing stage, such as... Figure 9 As shown:

[0074] (1) Position a0 is the initial position of the driving component;

[0075] (2) The drive assembly rotates clockwise from position a0 to position a1, the first moving blade 12 moves forward, and the second moving blade 22 remains stationary; the hook groove 123 of the first moving blade 12 is used to hold the sewing thread.

[0076] (3) The drive assembly rotates counterclockwise from position a1 to position a3. At this time, the first moving blade 12 and the second moving blade 22 move towards each other. The hook groove 123 of the first moving blade 12 drives the sewing thread towards the direction of the second moving blade. The sewing thread will automatically be inserted into the receiving groove and then pressed on the first cutting edge 121 of the front hole groove 122. The second cutting edge 221 of the second moving blade 22 slides towards the front hole groove 122. At position a3, the second cutting edge 221 cooperates with the first cutting edge 121 to cut the sewing thread.

[0077] (4) The drive assembly rotates counterclockwise from position a3 to position a4, and the first moving blade 12 and the second moving blade 22 continue to move towards each other; at position a4, the second moving blade is reset under the action of the spring;

[0078] (5) The drive component rotates counterclockwise from position a4 to position a0, and the first moving blade 12 also completes its reset.

[0079] The main difference between the finishing sewing stage and the starting sewing stage lies in the initial process of hooking the sewing thread with the first cut.

[0080] Example 2, as a new variation, such as Figure 11As shown, the shape of the new first moving blade 80 has been changed. The original front groove 122 and hook groove 123 have been merged into a new combined groove 801. A second cutting edge 802 is provided on the front side of the combined groove 801, and a second hook groove 803 is provided on the rear side of the combined groove. The steps of this new first moving blade 80 are the same in the starting and ending sewing stages; Figure 9 At position a1, the combined groove 801 of the new first moving blade 80 allows the needle to enter and complete the hooking of the top thread during the starting stage of sewing. The second hooking groove 803 of the combined groove 801 can complete the hooking of the sewing thread at the end of the sewing stage. The thread is cut directly from position a1 to position a3, and the subsequent steps remain unchanged.

[0081] Example 3 is basically the same as Example 1, except that the transmission structure is different. Specifically, the first transmission component and the second transmission component have different structures.

[0082] The first transmission assembly 40 includes a third crank 61, a slider 66, a sliding groove 62, a first transmission shaft 63, a fourth crank 64, and a third connecting rod 65. The third crank 61 is fixed to the motor shaft, and the slider 66 is hinged to the swing end of the third crank 61. The slider 66 is disposed in the sliding groove 621 of the sliding groove 62, which is fixed to the first transmission shaft 63. The swing of the third crank 61 drives the first transmission shaft 63 to swing. The fourth crank 64 is fixed to the other end of the first transmission shaft 63, and drives the first moving blade assembly 10 through the third connecting rod 65. The cooperation between the slider 66 and the sliding groove 62 allows the third crank to rotate 360° without obstruction. That is, the motor can rotate 360°. During one revolution of the motor, the first moving blade moves forward and backward. The angle region corresponding to the backward movement of the first moving blade is then allocated to the second transmission assembly, and the second moving blade moves forward within this angle region, thus completing the wire cutting action.

[0083] The second transmission assembly 50 includes a second drive cam 71, a fifth crank 72, a second transmission shaft 73, a sixth crank 74, and a fourth connecting rod 75. The second drive cam and the fifth crank constitute the intermittent motion mechanism 59. The second drive cam is provided with a working surface 711 and a non-working surface 712. The working surface transmits power to the fifth crank 72, while the non-working surface isolates the power transmission between the second drive cam and the fifth crank. A roller 721 is mounted on the swing end of the fifth crank 72. The fifth crank is fixed on the second transmission shaft 73, which directly or indirectly transmits power to the second moving tool assembly. This design ensures that when the first transmission assembly is working, the second transmission assembly is not actually working within a certain angular range, achieving the technical objective of keeping the second moving tool stationary while the first moving tool advances.

[0084] The first drive shaft 63 is a hollow bushing, and the second drive shaft 73 is a core rod; the second drive shaft 73 passes through the first drive shaft 63, and the two are concentrically arranged. This design simplifies the transmission structure and improves transmission precision.

[0085] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of this invention, should still fall within the scope of the disclosed technical content. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention.

[0086] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.

[0087] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

Claims

1. A double-moving blade assembly for the thread-cutting mechanism of a sewing machine, characterized in that, It includes a first moving blade assembly (10) and a second moving blade assembly (20); both the first moving blade assembly (10) and the second moving blade assembly (20) are rotatably mounted on the outside of the adapted rotary hook mechanism; the first moving blade assembly is used to hook the sewing thread, and the second moving blade assembly cooperates with the first moving blade assembly to cut the sewing thread; The first moving blade assembly (10) includes a first moving blade holder (11) and a first moving blade (12); the tip of the first moving blade is provided with a first cutting edge (121). The second moving blade assembly (20) includes a second moving blade holder (21) and a second moving blade (22); The second moving blade (22) is positioned above the first moving blade (12), with the front end of the second moving blade (22) abutting against the upper surface of the first moving blade (12), and the front end of the second moving blade is provided with a second cutting edge (221). The first moving blade (12) and the second moving blade (22) are both located on the same side of the needle position.

2. The double-moving blade assembly of the sewing machine thread-cutting mechanism according to claim 1, characterized in that, During the thread cutting process, the first moving blade (12) first rotates in the first direction to a set position, and then rotates in the second direction and drives the sewing thread; when the first moving blade rotates in the second direction, the second moving blade (22) rotates in the first direction, and the second moving blade (22) slides on the surface of the first moving blade (12), and the second cutting edge (221) cooperates with the first cutting edge (121) to cut the sewing thread; the first direction rotation is counterclockwise rotation, and the second direction rotation is clockwise rotation; or, the first direction rotation is clockwise rotation, and the second direction rotation is counterclockwise rotation; The first moving blade holder has a first ring part (111) in the middle, which is used to rotate and be fitted on the outside of the rotary hook mechanism (30); the first ring part (111) is provided with a first drive part (112) and the first moving blade (12). The second moving tool holder (21) is provided with a second ring part (211) in the middle, which is used to rotate and be fitted on the outside of the rotary hook mechanism; the second ring part is provided with a second drive part (212) and a second moving tool (22). The first moving blade (12) has a front hole groove (122) and a hook groove (123) arranged along the rotation direction of the first moving blade (12); the front hole groove (122) is located at the tip of the first moving blade (12), and the first cutting edge (121) is located at the front edge of the front hole groove (122); the hook groove (123) is located in the middle of the first moving blade, and the hook groove (123) has an opening (1231) for hooking the thread; a receiving groove (124) for receiving sewing thread is provided between the front hole groove and the hook groove. The front hole groove (122) and / or hook groove (123) allow the sewing machine needle to pass through.

3. The double-moving blade assembly of the sewing machine thread-cutting mechanism according to claim 2, characterized in that: The first ring portion (111) and the second ring portion (211) are arranged side by side, or the first ring portion (111) and the second ring portion (211) are fitted together inside and outside; The first ring portion (111) and the second ring portion (211) are arranged on the same axis.

4. The thread-cutting mechanism of a sewing machine, characterized in that: Includes the dual-moving blade assembly as described in any one of claims 1-3; further includes: The first transmission assembly (40) is used to drive the first moving blade assembly (10). The second transmission assembly (50) is used to drive the second moving blade assembly (20); A drive assembly for driving the first transmission assembly (40) and the second transmission assembly (50). The second transmission assembly (50) includes an intermittent motion mechanism (59); during the rotation of the first moving blade (12) in the first direction, the intermittent motion mechanism (59) isolates the power transmission between the drive assembly and the second moving blade assembly (20); during the rotation of the first moving blade (12) in the second direction, the intermittent motion mechanism (59) transmits the power of the drive assembly to the second moving blade assembly (20).

5. The thread-cutting mechanism of the sewing machine according to claim 4, characterized in that: The first transmission assembly includes a first crank (41) and a first connecting rod (42); one end of the first crank (41) is driven by the drive assembly, the other end of the first crank is hinged to one end of the first connecting rod (42), and the other end of the first connecting rod is hinged to the first drive part (112) of the first moving tool holder. The second transmission assembly includes a drive cam (51), a second drive crank (52), and a second connecting rod (53); one end of the second connecting rod (53) is hinged to the second drive part (212) of the second moving tool holder, and the other end of the second connecting rod (53) is hinged to one end of the second drive crank (52), and the second drive crank is rotatably mounted on the frame; the drive cam (51) is driven by the drive assembly; An intermittent motion mechanism (59) is provided between the second drive crank (52) and the drive cam (51); the intermittent motion mechanism (59) includes a movable or deformable abutment (54); the abutment (54) is provided at one end of the second drive crank (52), and one side of the drive cam (51) abuts against the abutment (54); during the first moving blade (12) rotating in the first direction, the abutment moves or deforms and counteracts the transmission of the drive cam (51); during the first moving blade (12) rotating in the second direction, the abutment (54) transmits power to the second drive crank (52).

6. The thread-cutting mechanism of the sewing machine according to claim 5, characterized in that: The lower part of the second drive crank (52) is provided with a guide groove (522). The abutment part (54) includes a moving rod (545) disposed in the guide groove (522). An elastic member (541) is disposed in the guide groove (522). The elastic member (541) is used for the reset of the moving rod (545). When the drive cam (51) applies force to the end (544) of the moving rod, the moving rod (545) retracts into the guide groove (522) and isolates the power transmission. When the drive cam abuts against the side (543) of the moving rod, the drive cam drives the second drive crank (52) through the moving rod.

7. The thread-cutting mechanism of the sewing machine according to claim 4, characterized in that: The first transmission assembly (40) includes a third crank (61), a slider (66), a sliding groove (62), and a first transmission shaft (63); the third crank (61) is fixed on the motor shaft, and the slider (66) is hinged to the swing end of the third crank (61). The slider (66) is disposed in the sliding groove (621) of the sliding groove (62), and the sliding groove (62) is fixed on the first transmission shaft (63); the swing of the third crank (61) drives the first transmission shaft (63) to swing; the other end of the first transmission shaft (63) directly or indirectly drives the first moving blade assembly (10).

8. The thread-cutting mechanism of the sewing machine according to claim 7, characterized in that: The The second transmission assembly (50) includes a second drive cam (71), a fifth crank (72), and a second transmission shaft (73); the second drive cam and the fifth crank constitute the intermittent motion mechanism (59); the second drive cam is provided with a working surface (711) and a non-working surface (712), the working surface transmits power to the fifth crank (72), and the non-working surface isolates the power transmission between the second drive cam and the fifth crank; the fifth crank is fixed on the second transmission shaft (73), and the second transmission shaft transmits power directly or indirectly to the second moving tool assembly.

9. The thread-cutting mechanism of the sewing machine according to claim 8, characterized in that: The first drive shaft (63) is a hollow bushing, and the second drive shaft (73) is a core rod; the second drive shaft (73) passes through the first drive shaft (63), and the two are concentrically arranged.

10. A sewing machine, characterized in that, Includes the wire-cutting mechanism as described in any one of claims 4-9.

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