Straight knife type thread trimming mechanism and template machine

Abstract

The invention belongs to the technical field of sewing machines, and particularly relates to a straight knife type thread trimming mechanism and a template machine. The straight knife type thread trimming mechanism comprises a machine shell, a first movable knife mechanism and a second movable knife mechanism; the first movable cutter is rotatably arranged on the machine shell by taking the rotating shuttle shaft as the center; the first trimming motor is fixed to the machine shell and used for driving the first movable cutter. The first movable cutter is used for driving the sewing thread to the second movable cutter mechanism; the second movable cutter mechanism is used for being matched with the first movable cutter mechanism to cut off the sewing thread and comprises a second thread cutting motor, a second movable cutter and a guide assembly; the second trimming motor drives the guide assembly to move in the set direction through the crank assembly. The second moving cutter is installed on the guide assembly and has a first position and a second position in the set direction. The first position is closer to the first moving cutter than the second position; when in the first position, the cutting edge of the second movable cutter is matched with the cutting edge of the first movable cutter to execute thread trimming action; at the second position, the cutting edge is separated from the first movable cutter, so that the thread trimming action is efficient and reliable, and maintenance is convenient.

Description

Technical Field

[0001] The invention belongs to the technical field of sewing machines, in particular to a straight knife type thread trimming mechanism and a template machine. Background Art

[0002] A sewing machine is a machine that uses sewing thread to form one or more stitches on the material to be sewn, so that one or more layers of material are interwoven or sewn together. It is usually composed of a base (i.e., a casing and a bottom plate), a needle bar mechanism, a feeding mechanism, a thread hook mechanism, a presser foot mechanism, a thread trimming mechanism and accessories, and each mechanism works in a cycle.

[0003] For example, Chinese patent CN201810877711.5 discloses a lower section mechanism of a template machine, which includes a fixed frame and a rotating motor, a lower head is fixed on the output shaft of the rotating motor, a rotary hook shaft is provided on the lower head, and a rotary hook motor for driving the rotary hook shaft to rotate is fixed on the lower head. A driving member for driving the thread cutting is provided on the lower head, and the driving member drives the connecting rod mechanism and the matching cutter to cut the sewing thread. This structure is a more common thread cutting structure of a template machine, which will leave longer thread ends on the surface of the fabric; in the next sewing process, bird's nest-shaped thread ends will also be formed on the sewn clothes, affecting the quality of the entire clothes.

[0004] In order to further optimize the cutting of thread ends, such as Chinese patent CN202210095960.5, the patent discloses a three-dimensional sewing template machine that can automatically cut the thread ends, and the thread ends of the sewing thread are cut by the configured automatic thread cutting device. The automatic thread cutting device of this technical solution needs to be equipped with two rotating shearing parts, which are opened or closed around the hinge point and perform the thread cutting action. Its structure is similar to scissors; the overall structure of the device is relatively complex, and the production and maintenance costs are relatively high. Summary of the invention

[0005] The purpose of the present invention is to provide a straight knife type thread trimming mechanism and a template machine, which can effectively shorten the threads in the sewing process, have a simple structure, and have low production and maintenance costs.

[0006] The purpose of this technical solution is achieved in this way:

[0007] A straight knife type thread cutting mechanism, comprising a housing,

[0008] The first movable knife mechanism comprises a first thread trimming motor and a first movable knife; the first movable knife is rotatably arranged in the housing with a rotary hook shaft as the center; the first thread trimming motor is fixed on the housing and used to drive the first movable knife; the first movable knife is used to bring the sewing thread to the second movable knife mechanism;

[0009] A second movable knife mechanism, which is used to cooperate with the first movable knife mechanism to cut the sewing thread;

[0010] The second movable knife mechanism comprises a second thread cutting motor, a second movable knife and a guide assembly;

[0011] The second thread trimming motor drives the guide assembly to move along a set direction via a crank assembly;

[0012] The second movable knife is installed on the guide assembly and has a first position and a second position in the set direction; the first position is closer to the first movable knife than the second position; when the second movable knife is in the first position, the cutting edge of the second movable knife cooperates with the cutting edge of the first movable knife to perform the thread cutting action; when the second movable knife is in the second position, the cutting edge of the second movable knife is separated from the first movable knife.

[0013] Through the above technical solution, when a straight knife thread trimming mechanism is used normally, the first thread trimming motor drives the first movable knife to rotate around the rotary shuttle shaft to guide the sewing thread to the direction of the second movable knife mechanism; at this time, the second thread trimming motor drives the guide assembly to move in the set direction through the crank assembly, so that the second movable knife installed thereon can switch back and forth between the second position and the first position. When thread trimming is required in the sewing start stage and the end stage, when the second movable knife moves from the second position to the first position, it slides along the surface of the first movable knife and the cutting edge intersects with the cutting edge position of the first movable knife, and the two form a shearing cooperation to achieve precise cutting of the sewing thread; after the thread trimming is completed, the second movable knife retreats to the second position with the guide assembly, and the cutting edge completely leaves the working range of the first movable knife to avoid interfering with the normal routing of the sewing machine. This structure simplifies the complex movement of the traditional thread trimming mechanism through the independent drive of dual motors and the linear control of the guide assembly, making the thread trimming action efficient, reliable and convenient to maintain.

[0014] Preferably, the first movable knife is provided with a thread hole groove, a thread hook groove 1 and a thread hook groove 2 respectively located on opposite sides of the width of the first movable knife. The thread hole groove is used for the needle to pass through and hook the sewing thread in the sewing start stage. The thread hook groove 1 and the thread hook groove 2 are used together to hook the sewing thread in the finishing stage, so that the sewing thread is at the cutting edge position of the first movable knife.

[0015] Through the above technical scheme, in the sewing start stage, the first movable knife rotates until the thread hole slot is aligned with the position of the needle, the needle first passes through the thread hole slot downward, then leaves the thread hole slot upward and is lifted to a suitable position above the casing, completing the first needle lowering action of the needle; the thread take-up rod of the sewing machine takes up the thread upward and drives the surface thread on the needle to retreat; the sewing thread on the needle remains in the thread hole slot, and the first movable knife brings the sewing thread to the second movable knife mechanism and cooperates with it to cut the thread end when sewing starts.

[0016] When sewing is completed, in the finishing stage, the first movable knife rotates in the first direction to pass through the thread loop, and retreats in the second direction so that the thread hooking grooves 1 and 2 on both sides hook the line segment of the sewing thread and pull it to the second movable knife mechanism and cooperate with it to cut the thread end at the end.

[0017] Preferably, the guide assembly comprises a slide groove and a slider;

[0018] The slide groove is arranged on the housing;

[0019] The slider is installed in the slide groove, and a clamping groove is provided in the middle of the slider;

[0020] The second movable knife is mounted on the slider;

[0021] The crank assembly is rotatably mounted on the casing, one end of the crank assembly is arranged in the slot and drives the slider, and the other end of the crank assembly is connected to the second thread trimming motor.

[0022] Through the above technical scheme, the cooperation between the slide groove and the slider in the guide assembly is fixed to the casing through the slide groove to provide a linear guide constraint, the slider is embedded in the slide groove and slides back and forth along its length direction, and the slot in the middle of the slider forms a hinged cooperation with the movable end of one end of the crank assembly, so that the rotational motion of the crank assembly is converted into the linear motion of the slider; in the operation process, the second wire cutting motor drives the crank assembly so that its end slides in the slot and pushes the slider to move along the slide groove, thereby driving the second moving knife fixed to the slider to perform a linear shearing action; this structure reduces the risk of motion deviation through high-precision guiding of the slide groove and the slider, and the hinged design of the crank and the slot realizes the smoothness of power transmission. At the same time, the modular layout further optimizes assembly efficiency and maintenance convenience.

[0023] Preferably, the crank assembly comprises a rotating block, a connecting rod and a crank rod connected to the driving shaft of the second thread trimmer motor;

[0024] The two ends of the linkage rod are respectively hinged on the rotating block and the crank rod, the crank rod is hinged to the housing, and the crank rod has a movable block, and the movable block is embedded in the slot;

[0025] When the second thread trimming motor drives the rotating block to rotate, the linkage rod is driven to swing to rotate the crank rod, so that the movable block drives the slider to move along the slide groove in the slot.

[0026] Through the above technical scheme, the second thread cutting motor drives the rotating block through the rotation of the driving shaft, and the two ends of the connecting rod are respectively hinged with the rotating block and the crank rod to form a connecting rod mechanism with two degrees of freedom, and the crank rod forms a fixed-axis rotation through the hinge point of the casing, and the circular motion of the rotating block is converted into a fixed-axis swing of the crank rod, and its end is embedded in the slider slot by the movable block to form a sliding combination, which slides along the slot track to promote the precise linear movement of the slider in the slide slot, thereby completing the shearing action of driving the second moving knife. Through the composite transmission of multi-stage articulation and sliding pair, the inertial impact when the motor directly drives the slider is reduced, and the leverage effect of the multi-rod setting amplifies the driving torque, improves the response speed of the shearing action, and makes the shearing action more stable.

[0027] Preferably, a wire clamp is provided on one side of the guide assembly and fixed on the housing; when the first movable knife rotates to a set position toward the second movable knife, the wire clamp passes through the threading hole on the first movable knife and presses against the lower side of the first movable knife.

[0028] Through the above technical solution, in the sewing start stage, when the first movable knife drives the sewing thread close to the second movable knife, the thread clamp presses the sewing thread end passing through the thread hole groove and presses it against the lower side wall of the first movable knife to position it, thereby avoiding shearing deviation caused by wire sliding, improving the smoothness of thread cutting, reducing tool wear caused by sewing thread vibration, and optimizing the reliability of the shearing action.

[0029] Preferably, a suction device is further provided on one side of the guide assembly; and a suction port of the suction device faces the first movable knife.

[0030] Through the above technical solution, the suction port of the suction device is facing the shearing area of ​​the first movable knife. When the first movable knife and the second movable knife complete wire shearing, the suction device is immediately started, and the cut thread ends are sucked into the internal channel of the suction port through the gap between the movable knives through the negative pressure airflow, and are directly discharged or collected to quickly remove the residual thread ends, thereby avoiding the accumulation of thread ends on the surface of the movable knife or in the slide groove to cause jamming or blockage, reducing the frequency of manual cleaning, and improving the self-cleaning ability and long-term operation reliability of the equipment.

[0031] Preferably, the first thread trimming motor drives the first movable knife to move circumferentially around the rotary hook shaft through a transmission structure, and the transmission structure includes a transmission component 1, a main shaft rotatably arranged on the housing, and a transmission component 2;

[0032] Wherein, the transmission assembly 1 includes a transmission rod 1 connected to the driving shaft of the first thread trimmer motor and a transmission rod 2 arranged on the main shaft, a guide groove is provided on the end face of the transmission rod 2 close to the transmission rod 1, and a guide block is provided corresponding to the rotation of the transmission rod 1, and the guide block is embedded in the guide groove to make the transmission rod 2 and the transmission rod 1 movably cooperate;

[0033] The transmission component 2 includes a first crank, a second crank and a swinging ring. The first crank is connected to one end of the main shaft away from the transmission rod 2. Both ends of the second crank are respectively hinged on the first crank and the first ring. The first movable knife is installed on the swinging ring, and the swinging ring is rotatably mounted on the rotary hook shaft.

[0034] Through the above technical scheme, the first thread trimming motor drives the output shaft to rotate, and the output shaft drives the transmission rod 1 fixed thereon to rotate. When the transmission rod 1 rotates with the motor drive shaft, the end guide block thereof slides along the guide groove on the end face of the second transmission rod, and converts the rotational motion into the activity of the second transmission rod. The second transmission rod drives the main shaft to rotate synchronously, so that when the first crank at the other end of the main shaft rotates, the swinging ring is driven to rotate circumferentially around the rotary shuttle shaft through the activity of the second crank, thereby driving the first moving knife fixed on the swinging ring to perform the hooking and pulling actions of the sewing thread, thereby realizing the high-stability trajectory control of the first moving knife as a whole, and optimizing the shearing synchronization and the durability of the mechanism.

[0035] Preferably, a cutter mounting seat is installed on the casing, and the slide groove is arranged in the length direction of the cutter mounting seat; a left baffle plate and a right baffle plate are respectively arranged on the left and right sides of the length direction of the cutter mounting seat, and the left baffle plate and the right baffle plate constrain the slider in the slide groove.

[0036] Through the above technical solution, the left baffle plate and the right baffle plate are respectively installed on both sides of the slide slot to form a double-sided limiting structure, which limits the slider from detaching from the slide slot opening and keeps it moving stably along the length direction of the slide slot.

[0037] A template machine, comprising the above-mentioned straight knife type thread cutting mechanism;

[0038] A rotating connection portion is provided at the bottom of the housing, and the rotating connection portion is used to connect the rotating device;

[0039] A longitudinal rotary hook shaft is arranged on the rear side of the middle part of the casing.

[0040] A first thread trimming motor is disposed laterally on the lower side of the left portion of the housing, and the first thread trimming motor is located on the left side of the rotary hook shaft;

[0041] A second thread trimming motor is vertically arranged on the rear side of the right part of the housing, and the second thread trimming motor is located on the right side of the rotary hook shaft.

[0042] Through the above technical scheme, the bottom of the casing of the straight knife thread trimming mechanism in the template machine is connected to the external rotating device through a rotating connection part, the rotary hook shaft longitudinally arranged on the rear side of the middle part of the casing provides a support axis for the circumferential swing of the first movable knife, the first thread trimming motor is horizontally arranged on the lower left side of the casing, and drives the first movable knife to rotate around the rotary hook shaft through the transmission assembly, and the second thread trimming motor is vertically installed on the rear side of the right part of the casing, and drives the second movable knife to move in a straight line along the slide groove through the crank assembly; the interference of the power transmission path is reduced, the overall rigidity of the casing is enhanced, the rotating connection part absorbs the vibration interference of the external rotating device, and combined with the axial bearing of the rotary hook shaft on the shear force, the synchronization accuracy and mechanism stability during high-speed shearing of the double movable knives are significantly improved.

[0043] Compared with the prior art, the technical solution has the following outstanding and beneficial technical effects:

[0044] 1. This technical solution achieves the shortening of the sewing thread through the cooperation of the first movable knife mechanism and the second movable knife mechanism, and the shortening effect is good; the second movable knife mechanism adopts the form of a straight knife, and the second movable knife moves along a straight line and approaches the first movable knife to shorten the sewing thread at a set position; the effect of shortening the sewing thread ends is very good, which effectively improves the quality of clothing.

[0045] 2. The second movable knife mechanism of the present technical solution adopts the form of a straight knife, and the overall structure of the second thread trimming motor transmitting power to the second movable knife is completely independent, has less dependence on the existing sewing machine structure, and is not easy to cause mechanical conflict or control conflict. The second thread trimming motor can control the movement of the second movable knife more accurately, and better realize the shortening of the sewing thread.

[0046] 3. This technical solution is designed on the basis of the template machine, but it can also be applied to lockstitch machines or other special sewing machines, and has the characteristics of wide adaptability.

[0047] 4. When this technical solution is applied to the template machine, a first thread trimming motor is horizontally arranged on the lower side of the left part of the casing, and a second thread trimming motor is vertically arranged on the rear side of the right part of the casing. The two motors are respectively located on both sides of the rotation center, which can balance the overall center of gravity to a certain extent, reduce working noise and increase service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 Schematic diagram of the overall structure of this embodiment;

[0049] Figure 2 For this embodiment Figure 1 Schematic diagram from another perspective;

[0050] Figure 3 It is a schematic diagram of the overall structure of the straight knife type thread cutting mechanism of the embodiment;

[0051] Figure 4It is a partial exploded schematic diagram of the first moving knife mechanism in the straight knife type thread trimming mechanism of the embodiment;

[0052] Figure 5 Schematic diagram of the overall structure of the second movable knife mechanism in the straight knife type thread trimming mechanism of the embodiment;

[0053] Figure 6 It is a partial explosion diagram of a guide assembly in a straight-knife type wire trimming mechanism of an embodiment;

[0054] Figure 7 This is a schematic diagram of the thread hooking operation of the thread hole slot in the seam starting stage in this embodiment;

[0055] Figure 8 It is a schematic diagram of the wire hooking operation of the wire hooking trough 1 and the wire hooking trough 2 in the finishing stage of this embodiment.

[0056] Reference numerals: 1, housing; 2, first moving knife mechanism; 21, first thread trimming motor; 22, first moving knife; 3, second moving knife mechanism; 31, second thread trimming motor; 32, second moving knife; 33, guide assembly; 331, slide groove; 332, slider; 4, crank assembly; 41, rotating block; 42, connecting rod; 43, crank rod; 5, slot; 6, movable block; 7, clamping piece; 8, air suction device; 9, Wire hole slot; 10, wire hook slot one; 11, wire hook slot two; 12, transmission component one; 121, transmission rod one; 122, transmission rod two; 13, main shaft; 14, transmission component two; 141, first crank; 142, second crank; 143, swing ring; 15, guide slot; 16, guide block; 17, cutter mounting seat; 18, left baffle; 19, right baffle; 20, rotating connection part; 23, rotary hook shaft. DETAILED DESCRIPTION

[0057] The specific implementation of the technical solution is further described in detail below with reference to the accompanying drawings.

[0058] Example:

[0059] See also Figure 1 and Figure 3 A straight knife thread trimming mechanism comprises a casing 1, a first movable knife mechanism 2 and a second movable knife mechanism 3 installed on the casing 1, wherein the first movable knife mechanism 2 comprises a first thread trimming motor 21 and a first movable knife 22, the first movable knife 22 is rotatably arranged on the casing 1 with a rotary hook shaft 23 as the center, the first thread trimming motor 21 is laterally fixed to the lower side of the left part of the casing 1, and is used to drive the first movable knife 22 to move; the second movable knife mechanism 3 comprises a second movable knife 32 and a second thread trimming motor 31, the second thread trimming motor 31 is vertically fixed to the rear side of the right part of the casing 1, and is used to drive the second movable knife 32 to move.

[0060] See also Figure 4The first thread trimming motor 21 drives the first movable knife 22 to rotate circumferentially around the rotary hook shaft 23 through a transmission structure. The transmission structure includes a transmission component 12, a main shaft 13 and a transmission component 2 14, wherein the transmission component 12 includes a transmission rod 121 and a transmission rod 2 122. The transmission rod 121 is clamped on the driving shaft of the first thread trimming motor 21 through a bolt adjustment expansion joint structure. The transmission rod 121 and the transmission rod 2 122 are movably matched. The specific matching method is that the transmission rod 1 121 is connected to a guide block by rotating the side of the transmission rod 121 close to the transmission rod 2 122. 16, which is in the shape of a cube, a guide groove 15 is opened on the corresponding side of the transmission rod 122, and its groove width and size are adapted to the guide block 16, the guide block 16 is embedded in the guide groove 15 and moves along its groove, and the end of the transmission rod 122 away from the transmission rod 1 121 is clamped on one end of the main shaft 13 through the structure of the bolt adjustment expansion joint, and the main shaft 13 is installed at a preset position on the casing 1 by a bearing sleeve, and is rotatably arranged relative to the casing 1, so that the transmission rod 122 can drive the main shaft 13 to rotate synchronously, and then the motor power is smoothly transmitted to the main shaft 13.

[0061] The transmission component 14 includes a first crank 141, a second crank 142 and a swinging ring 143. One end of the first crank 141 is connected to the other end of the main shaft 13 away from the transmission rod 122 by a key connection or an integral molding method. The second crank 142 is arc-shaped, one end of which is hinged to the end of the first crank 141 away from the main shaft 13, and the other end is hinged to the swinging ring 143. The swinging ring 143 is rotatably sleeved on the rotary shuttle shaft 23, and the first movable knife 22 is installed on the swinging ring 143. The rotation of the main shaft 13 is converted into the circumferential motion of the swinging ring 143, ensuring that the first movable knife 22 rotates accurately around the rotary shuttle shaft 23.

[0062] See also Figure 5 The second movable knife mechanism 3 also includes a guide assembly 33. The second thread trimming motor 31 drives the guide assembly 33 to move along the set direction through the crank assembly 4, wherein the crank assembly 4 includes a rotating block 41, a connecting rod 42 and a crank rod 43. The rotating block 41 is fixed to the driving shaft of the second thread trimming motor 31 through the structure of a bolt-adjusting expansion joint, and one end thereof is hinged to the connecting rod 42, and the other end of the connecting rod 42 away from the rotating block 41 is hinged to the crank rod 43. The crank rod 43 is V-shaped, and its middle part is hinged on the casing 1.

[0063] See also Figure 6The guide assembly 33 includes a slide groove 331 and a slider 332. The slide groove 331 is arranged on the casing 1. Specifically, a cutter mounting seat 17 is installed on the casing 1. The slide groove 331 is arranged on the upper end surface of the cutter mounting seat 17 along the length direction. The slider 332 is adapted to the slide groove 331. The slider 332 is embedded in the slide groove 331 and moves along its length direction. The second movable knife 32 is installed on the slider 332; the cutter mounting seat 17 is installed with a left baffle 18 and a right baffle 19. The two baffles are respectively fixed to the left and right sides of the cutter mounting seat 17 along the length direction by bolts, and extend relatively to the inside to the opening of the slide groove 331, forming a shielding effect, so that the left baffle 18 and the right baffle 19 can cooperate to constrain the slider 332 in the slide groove 331.

[0064] A slot 5 is provided in the middle of the slider 332, and the slot 5 is opened on the upper end surface of the slider 332. The crank rod 43 has a movable block 6 adapted to the slot 5, which is located at the other end of the crank rod 43 away from the hinged position with the connecting rod 42. The movable block 6 is embedded in the slot 5. When the second thread cutting motor 31 is started, its driving shaft drives the rotating block 41 to rotate, and the rotating block 41 drives the crank rod 43 to rotate axially through the connecting rod 42. The movable block 6 slides in the slot 5 and pushes the slider 332 to move in a straight line along the slide slot 331 of the cutter mounting seat 17. The second movable knife 32 has a first position and a second position in the set direction, thereby realizing the reciprocating switching of the second movable knife 32 between the first position and the second position.

[0065] See also Figure 3 , Figure 7 and Figure 8 A thread clamping piece 7 is provided on one side of the guide assembly 33, and the thread clamping piece 7 is fixed on the casing 1. When the first movable knife 22 rotates to the side of the second movable knife 32 to a set position, the thread clamping piece 7 passes through the thread hole on the first movable knife 22 and can press against the lower side of the first movable knife 22 to press the sewing thread; a suction device 8 is also provided on one side of the guide assembly 33, and the suction port of the suction device 8 can face the first movable knife 22.

[0066] The first movable knife 22 is provided with a thread hole groove 9, a thread hook groove 10 and a thread hook groove 2 11. The thread hole groove 9 and the thread hook groove 10 are arranged along the rotation direction of the first movable knife 22. The thread hole groove 9 is located at one end of the first movable knife 22 close to the cutting edge. The thread hole groove 9 is used for the needle to pass through and to hook the sewing thread at the start of sewing. The thread hook groove 10 and the thread hook groove 2 11 are respectively located on the opposite sides of the middle part of the first movable knife 22 in a one-to-one correspondence, and both have openings facing outwards. The openings on both sides are used to hook the sewing threads on both sides into the corresponding thread hook grooves at the end of sewing to achieve thread hooking.

[0067] In the sewing start stage, the first thread cutting motor 21 drives the first movable knife 22 to rotate around the shuttle shaft 23 so that its thread hole slot 9 is aligned with the bottom of the needle. After the needle passes through the thread hole slot 9 to complete the sewing of the first stitch, the thread take-up rod pulls back the surface thread, and the sewing thread is retained in the thread hole slot 9. The first movable knife 22 continues to rotate to guide the sewing thread to the direction of the second movable knife 32. The thread clamping piece 7 presses the sewing thread end, and the needle performs the second stitch. The surface thread on the needle is locked with the bottom thread in the shuttle shaft 23, tightening the section of surface thread to prevent the second needle from lifting and bringing it out of the thread hole slot 9, ensuring that the subsequent cut thread is not easy to loosen until the second needle thread locking is completed.

[0068] The second thread cutting motor 31 drives the second movable knife 32 to move through the crank assembly 4 and the guide assembly 33, and drives the second movable knife 32 to move in a straight line from the second position (away from the first movable knife 22) to the first position (close to the first movable knife 22), so that the cutting edge of the second movable knife 32 slides along the surface of the first movable knife 22 and intersects with the cutting edge of the first movable knife 22, thereby forming a shearing force, and accurately cutting the starting thread end. After the thread cutting is completed, the second movable knife 32 returns to the second position and leaves the working area to avoid interfering with subsequent sewing. The suction device 8 sucks away the thread end through the suction port, and the needle continues to sew until the sewing operation is completed.

[0069] In the finishing stage, the first movable knife 22 rotates in the first direction, passes through the thread loop and then retreats in the opposite direction. The openings of the two thread hooking grooves on the opposite sides respectively face and hook the sewing threads on both sides, and the threads are pulled to the second movable knife 32. Part of the sewing thread segment bypasses the bottom of the first movable knife 22, and the second movable knife 32 moves from the second position to the first position again to complete the secondary shearing, finishing the thread ends and ending the thread trimming.

[0070] The specific working process of this program is as follows:

[0071] The present technical solution guides the sewing thread to the direction of the second movable knife mechanism 3 by driving the first movable knife 22 to rotate around the rotary hook shaft 23 after the first thread trimming motor 21; at this time, the second thread trimming motor 31 drives the guide assembly 33 to move in the set direction through the crank assembly 4, so that the second movable knife 32 installed thereon can switch back and forth between the second position and the first position. When thread trimming is required in the sewing starting stage and the ending stage, when the second movable knife 32 moves from the second position to the first position, it slides along the surface of the first movable knife 22 and the cutting edge intersects with the cutting edge position of the first movable knife 22, and the two form a shearing cooperation to achieve accurate cutting of the sewing thread; after the thread trimming is completed, the second movable knife 32 retreats to the second position with the guide assembly 33, and the cutting edge completely leaves the working range of the first movable knife 22 to avoid interfering with the normal routing of the sewing machine. The structure simplifies the complex movement of the traditional thread trimming mechanism through the independent drive of the dual motors and the linear control of the guide assembly 33, so that the thread trimming action is efficient, reliable and convenient to maintain.

[0072] A template machine includes a template machine body, a casing 1 having a rotary hook shaft 23 and a rotating connection part 20 at the bottom, which is used to be installed to the template machine body and connect to the rotating device, the rotary hook shaft 23 is longitudinally arranged at the rear side of the middle part of the casing 1, the first thread cutting motor 21 is located on the left side of the rotary hook shaft 23, and the second thread cutting motor 31 is located on the right side of the rotary hook shaft 23.

[0073] The above shows and describes the basic principle and main features of the technical solution and the advantages of the technical solution. The technicians in this industry should understand that the technical solution is not limited by the above embodiments. The above embodiments and the description are only to illustrate the principle of the technical solution. Without departing from the spirit and scope of the technical solution, the technical solution will have various changes and improvements, which fall within the scope of the technical solution to be protected. The scope of protection claimed by the technical solution is defined by the attached claims and their equivalents.

Claims

1. A straight knife type thread cutting mechanism, comprising: Housing (1), The first movable knife mechanism (2) comprises a first thread trimming motor (21) and a first movable knife (22); the first movable knife (22) is rotatably arranged in the housing (1) with a rotary hook shaft as the center; the first thread trimming motor (21) is fixed on the housing (1) and is used to drive the first movable knife (22); The first movable knife (22) is used to bring the sewing thread to the second movable knife mechanism; a second movable knife mechanism (3), which is used to cooperate with the first movable knife mechanism (2) to cut the sewing thread; It is characterized in that The second movable knife mechanism (3) comprises a second thread cutting motor (31), a second movable knife (32) and a guide assembly (33); The second thread trimming motor (31) drives the guide assembly (33) to move along a set direction via a crank assembly (4); The second movable knife (32) is mounted on the guide assembly (33) and has a first position and a second position in the set direction; the first position is closer to the first movable knife (22) than the second position; when the second movable knife (32) is in the first position, the cutting edge of the second movable knife (32) cooperates with the cutting edge of the first movable knife (22) to perform a thread cutting action; when the second movable knife (32) is in the second position, the cutting edge of the second movable knife (32) is separated from the first movable knife (22).

2. A straight knife type thread cutting mechanism according to claim 1, characterized in that: The first movable knife (22) is provided with a thread hole groove (9), a thread hooking groove 1 (10) and a thread hooking groove 2 (11) respectively located on opposite sides of the first movable knife (22) along the width, the thread hole groove (9) is used for allowing the needle to pass through and hook the sewing thread in the sewing start stage, and the thread hooking groove 1 (10) cooperates with the thread hooking groove 2 (11) to hook the sewing thread in the finishing stage, so that the sewing thread is at the cutting edge of the first movable knife (22).

3. A straight knife type thread cutting mechanism according to claim 1, characterized in that: The guide assembly (33) comprises a slide groove (331) and a slide block (332); The slide groove (331) is arranged on the housing (1); The slider (332) is installed in the slide groove (331), and a clamping groove (5) is provided in the middle of the slider (332); The second movable knife (32) is mounted on the slider (332); The crank assembly (4) is rotatably mounted on the housing (1); one end of the crank assembly (4) is disposed in the slot (5) and drives the slider (332); the other end of the crank assembly (4) is connected to the second thread trimming motor (31).

4. A straight knife type thread cutting mechanism according to claim 3, characterized in that: The crank assembly (4) comprises a rotating block (41), a connecting rod (42) and a crank rod (43) connected to the driving shaft of the second thread trimmer motor (31); The two ends of the linkage rod (42) are respectively hinged on the rotating block (41) and the crank rod (43); the crank rod (43) is hinged on the housing (1); the crank rod (43) has a movable block (6); and the movable block (6) is embedded in the slot (5); When the second thread trimmer motor (31) drives the rotating block (41) to rotate, the linkage rod (42) is driven to swing to rotate the crank rod (43), so that the movable block (6) drives the slider (332) to move along the slide groove (331) in the slot (5).

5. A straight knife type thread cutting mechanism according to claim 2, characterized in that: A wire clamping piece (7) is provided on one side of the guide assembly (33), and the wire clamping piece (7) is fixed on the housing (1); when the first movable knife (22) rotates toward the second movable knife (32) to a set position, the wire clamping piece (7) passes through a threading hole on the first movable knife (22) and abuts against the lower side of the first movable knife (22).

6. A straight knife type thread cutting mechanism according to claim 2, characterized in that: A suction device (8) is also provided on one side of the guide assembly (33); the suction port (9) of the suction device (8) faces the first movable knife (22).

7. A straight knife type thread cutting mechanism according to claim 1, characterized in that: The first thread trimming motor (21) drives the first movable knife (22) to move circumferentially around the rotary hook shaft through a transmission structure, wherein the transmission structure comprises a transmission component 1 (12), a main shaft (13) rotatably arranged on the housing (1), and a transmission component 2 (14); The transmission assembly 1 (12) comprises a transmission rod 1 (121) connected to the driving shaft of the first thread trimming motor (21) and a transmission rod 2 (122) arranged on the main shaft (13); a guide groove (15) is provided on the end surface of one side of the transmission rod 2 (122) close to the transmission rod 1 (121); a guide block (16) is provided corresponding to the rotation of the transmission rod 1 (121); the guide block (16) is embedded in the guide groove (15) to enable the transmission rod 2 (122) to flexibly cooperate with the transmission rod 1 (121); The transmission assembly 2 (14) comprises a first crank (141), a second crank (142) and a swinging ring (143); the first crank (141) is connected to one end of the main shaft (13) away from the transmission rod 2 (122); the two ends of the second crank (142) are respectively hinged on the first crank (141) and the first ring; the first movable knife (22) is mounted on the swinging ring (143); and the swinging ring (143) is rotatably sleeved on the rotary hook shaft.

8. A straight knife type thread cutting mechanism according to claim 2, characterized in that: A cutter mounting seat (17) is mounted on the housing (1), and the slide groove (331) is arranged in the length direction of the cutter mounting seat (17); a left baffle plate (18) and a right baffle plate (19) are respectively arranged on the left and right sides of the length direction of the cutter mounting seat (17), and the left baffle plate (18) and the right baffle plate (19) constrain the slider (332) in the slide groove (331).

9. A template machine, characterized in that: A straight knife thread cutting mechanism comprising any one of claims 1 to 8; A rotating connection portion (20) is provided at the bottom of the housing (1), and the rotating connection portion (20) is used to connect to a rotating device; A longitudinal rotary hook shaft (23) is arranged at the rear side of the middle part of the housing (1). A first thread trimming motor (21) is disposed laterally on the lower side of the left portion of the housing (1), and the first thread trimming motor (21) is located on the left side of the rotary hook shaft (23); A second thread trimming motor (31) is vertically arranged on the rear side of the right part of the housing (1), and the second thread trimming motor (31) is located on the right side of the rotary hook shaft (23).

Images