A thread clamping drive mechanism and an embroidery machine

Abstract

This invention discloses a thread clamping drive mechanism, including a driver, a drive rod, and a transmission arm. The driver is mounted on the head housing of an embroidery machine. The drive rod is telescopically movable under the drive. The transmission arm has a rotating connection portion and is rotatably connected to the head housing of the embroidery machine. The first end of the transmission arm is driven by the drive rod. The second end of the transmission arm is used to drive the top rod of the thread clamping mechanism. The head housing has a vertically extending needle bar drive shaft, which is located between the first and second ends of the transmission arm. This invention also discloses an embroidery machine with this thread clamping drive mechanism. The advantages of this invention are that it can improve the smoothness of the drive operation, reduce the wear of the embroidery thread, and has a simple structure and low cost.

Description

Technical Field

[0001] This invention relates to a thread clamping drive mechanism and an embroidery machine, and is applied in the technical field of embroidery machines. Background Technology

[0002] In existing embroidery machine needle bar holders, the needle bar is equipped with a thread clamping mechanism. When the needle bar is embroidering, the thread clamping mechanism allows the embroidery thread to pass through. When the needle bar stops embroidering, the thread clamping mechanism clamps and fixes the embroidery thread, preventing it from continuing to feed the embroidery thread downward.

[0003] For example, prior art publication number CN205907487U discloses an embroidery machine housing with a built-in thread clamping driver. The thread clamping driver has a linearly driven thread clamping driver installed in the mounting hole. The thread clamping driver includes a push rod driven by an electromagnet. The electromagnet is installed on an electromagnet base. The electromagnet base has a guide groove for guiding the push rod. The push rod and the electromagnet are connected by a mounting block. The mounting block has a guide pin, which is engaged with the guide groove on the electromagnet base.

[0004] For example, prior art publication number CN207130460U discloses a thread clamping device for an embroidery machine. The drive rod pushing mechanism includes an electromagnet mounting base set on the machine head, an electromagnet is provided on the electromagnet mounting base, and a drive rod push plate is connected to the iron core of the electromagnet.

[0005] Both of the above-mentioned prior art disclose a thread clamping drive mechanism for driving the thread clamping mechanism. Due to the limited installation space of the embroidery machine head, to avoid mechanical interference, the pushing end of the transmission arm (top rod, drive rod push plate) of these two drive mechanisms is not on the central axis of the drive rod (the iron core of the electromagnet). Therefore, when these two drive mechanisms are in operation, the transmission arm will be subjected to a reaction force that acts on the drive rod. The direction of this reaction force is at a certain angle to the axial direction of the drive rod, resulting in a radial component force on the drive rod. This radial component force increases the frictional resistance on the drive rod, thus affecting the smoothness of the drive rod's extension and retraction, and may even cause the drive rod to jam. Furthermore, this radial component force also causes the drive rod to gradually wear down, making it more prone to breakage.

[0006] The existing technology has technical problems not only in the thread clamping drive mechanism, but also in the thread clamping mechanism itself.

[0007] For example, prior art publication CN209602790U discloses a thread clamping device for an embroidery machine, including a thread clamping seat and a pressure strip, each having a length structure. The cross-section of the thread clamping seat is U-shaped. The pressure strip is set in the U-shaped groove of the thread clamping seat and is set close to the rear wall of the U-shaped groove. A row of movable push rods moves through the thread clamping seat and the pressure strip. The row of movable push rods is arranged along the length direction of the thread clamping seat. A movable pressure block is sleeved on a section of the movable push rod located in the U-shaped groove. A telescopic spring is sleeved on the movable push rod exposed outside the thread clamping seat. The front end of the telescopic spring abuts against the thread clamping seat, and the rear end abuts against the push rod boss on the movable push rod. A row of thread-passing holes is opened on the top of the thread clamping seat, and a thread-passing ceramic sleeve is sleeved in the thread-passing holes.

[0008] When using it, the embroidery thread needs to be passed through the thread guide sleeve into the thread clamping seat, so that the embroidery thread passes through the thread clamping seat between the pressing strip and the moving pressing block. Since it is impossible to observe the situation inside the thread clamping seat, and the embroidery thread is prone to curling if it touches the pressing strip or the moving pressing block inside the thread clamping seat, the operation is not very convenient. In addition, the overall structure of this thread clamping device is relatively complex, with many components, making inspection and maintenance more troublesome and the cost relatively high.

[0009] For example, prior art publication number CN214422885U discloses a face wire clamping structure, including a clamping seat, a pressure plate, a push rod and a spring. The pressure plate is disposed on the clamping seat, the push rod is arranged in the front-back direction and its front end is connected to the pressure plate, and the spring is sleeved on the outside of the push rod.

[0010] Refer to the appendix of this invention patent Figure 6 The top of the pressure plate in this thread-holding structure is horizontally bent and has a groove to allow the embroidery thread to pass through. Due to the sheet-like structure of the pressure plate, the edges of the groove are relatively sharp, which can easily cut or even cut the embroidery thread, resulting in poor embroidery quality and interruption of the embroidery process. In addition, the vibration generated during the operation of the embroidery machine causes the top rod to rotate around its axis. Since the positioning effect of the pressure plate is poor, it is easy for it to rotate with the top rod, thus affecting the feeding state of the embroidery thread. Summary of the Invention

[0011] The technical problem to be solved by the present invention is to provide a thread clamping drive mechanism and an embroidery machine, which can improve the smoothness of drive operation, reduce the wear of embroidery thread, and has a simple structure and low cost.

[0012] The present invention is achieved through the following technical solution.

[0013] A thread clamping drive mechanism includes a driver, a drive rod, and a transmission arm; the driver is mounted on the head housing of an embroidery machine; the drive rod is telescopically movable under the drive; the transmission arm has a rotatable connecting part and is rotatably connected to the head housing of the embroidery machine; the first end of the transmission arm is driven by the drive rod; the second end of the transmission arm is used to drive the top rod of the thread clamping mechanism.

[0014] As a further improvement of the present invention, the head housing is provided with a vertically extending needle bar drive shaft, which is located between the first end and the second end of the transmission arm.

[0015] As a further improvement of the present invention, the rotating connection portion and the first end of the transmission arm are located on the same side of the needle bar drive shaft.

[0016] As a further improvement of the present invention, the portion between the rotating connection of the transmission arm and the second end is formed with a curved section to avoid the needle bar drive shaft.

[0017] As a further improvement of the present invention, the transmission arm is provided with a sliding groove extending along the arm body near the first end, and the drive rod is provided with a shaft that passes through the sliding groove and can slide along the sliding groove; the sliding groove is used to drive the drive rod and prevent the drive rod from rotating about its axis.

[0018] As a further improvement of the present invention, the sliding groove forms an opening at the first end, and the shaft is fixedly connected to the drive rod; or, the sliding groove is a closed groove, and the shaft is detachably connected to the drive rod; or, the sliding groove forms an opening at the first end, and the shaft is detachably connected to the drive rod.

[0019] As a further improvement of the present invention, the driver is configured as an electromagnetic driver.

[0020] An embroidery machine includes a machine head housing, a needle bar frame disposed on the front of the machine head housing, a thread clamping drive mechanism, and a thread clamping mechanism; the needle bar frame is provided with a vertically extending needle bar; the thread clamping mechanism includes a thread clamping plate, a top rod, a thread guide structure, and a thread clamping piece; the thread clamping plate is disposed on the front of the needle bar frame; the thread guide structure is disposed on the front of the thread clamping plate and has a thread guide groove that allows embroidery thread to pass through; the top rod passes through the needle bar frame and the thread clamping plate, the front end of the top rod is provided with the thread clamping piece, and the rear end is driven by the second end of the transmission arm; the top rod can move axially, so that the thread clamping piece and the thread clamping plate clamp or release the embroidery thread.

[0021] As a further improvement of the present invention, the upper part of the needle bar frame is provided with a thread take-up lever for guiding the embroidery thread; the thread take-up lever and the top lever are located on the same side of the needle bar.

[0022] As a further improvement of the present invention, the second end of the transmission arm is used to push the top rod to move forward along the axial direction so that the top thread clamping piece and the top thread clamping plate release the embroidery thread; the top rod is provided with an elastic reset structure for driving the top rod to reset so that the top thread clamping piece and the top thread clamping plate clamp the embroidery thread.

[0023] As a further improvement of the present invention, the face thread clamping piece is provided with a limiting groove through which the thread passing structure passes, for preventing the face thread clamping piece from rotating around the top rod.

[0024] As a further improvement of the present invention, the wire-passing structure includes a first arm and a second arm spaced apart from each other, with the wire-passing groove formed between them; within the normal working stroke range of the push rod moving along its axial direction, the first arm always remains in the state of passing through the limiting groove.

[0025] As a further improvement of the present invention, the top rod moves forward axially, and the face thread clamping piece and the second support arm separate, forming a gap between them, so that the embroidery thread can fall from outside the thread guide structure into the thread guide groove; or, the top rod moves forward axially, and the second support arm does not disengage from the space defined by the limiting groove, and the second support arm and the four groove walls of the limiting groove can form a gap, so that the embroidery thread can be inserted into the thread guide groove from outside the thread guide structure along the end of the second support arm.

[0026] As a further improvement of the present invention, the side of the second arm away from the cable groove is formed with a slope surface that gradually converges towards the end of the second arm.

[0027] As a further improvement of the present invention, the wire-passing structure is configured as a component made of ceramic or hardened steel.

[0028] The beneficial effects of this invention are:

[0029] 1. By setting up a transmission arm, the present invention can greatly reduce the radial force on the drive rod by utilizing the lever principle, thereby improving the smoothness of the drive rod's operation and avoiding situations such as excessive frictional resistance, jamming, or breakage.

[0030] 2. By arranging the positions of the first end, the second end, and the rotating connection part, the present invention can shorten the stroke of the drive rod, thereby reducing the overall length of the driver and facilitating installation in confined spaces; it can also reduce the rotation amplitude of the transmission arm, thereby minimizing the change in the direction of the force acting on the drive rod and improving the smoothness of the drive operation.

[0031] 3. The present invention, by setting a shaft on the drive rod and passing through the sliding groove of the transmission arm, can play a limiting role to prevent the drive rod from rotating around its axis, thereby reducing friction and further improving stability.

[0032] 4. The arrangement of the top rod, needle rod, and thread take-up rod in this invention can prevent the embroidery thread from jumping off due to the mechanical vibration of the embroidery machine when it is clamped.

[0033] 5. The present invention uses a top rod to drive the thread clamping piece and the thread clamping plate to clamp or release the embroidery thread. The overall structure is simpler and less expensive than the prior art.

[0034] 6. The thread structure of the present invention is less likely to damage the embroidery thread, and the structure of the first and second arms facilitates the embroidery thread to fall into the thread guide groove, making operation more convenient. Attached Figure Description

[0035] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings to aid in understanding the objectives and advantages of the present invention, wherein:

[0036] Figure 1 This is a schematic diagram of the embroidery machine.

[0037] Figure 2 This is a schematic diagram showing the separation of the head housing and the needle bar frame;

[0038] Figure 3 A schematic diagram of the head housing and the face wire clamping drive mechanism;

[0039] Figure 4 This is a schematic diagram of the surface wire clamping drive mechanism.

[0040] Figure 5 A schematic diagram of the first embodiment for the transmission connection between the transmission arm and the drive rod;

[0041] Figure 6 A schematic diagram of a second embodiment for the transmission connection between the transmission arm and the drive rod;

[0042] Figure 7 A schematic diagram of a third embodiment for the transmission connection between the transmission arm and the drive rod;

[0043] Figure 8 This is a front view of the needle bar holder;

[0044] Figure 9 This is a schematic diagram of the surface wire clamping mechanism;

[0045] Figure 10 This is a top view schematic diagram of the face wire clamping mechanism;

[0046] Figure 11 This is a schematic diagram of the through-line structure. Detailed Implementation

[0047] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0048] The directional terms such as up, down, left, right, front, back, front, back, top, and bottom mentioned or possibly used in this specification are defined relative to the construction shown in the accompanying drawings. The terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively. These are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive.

[0049] Reference Figure 1 , Figure 2 An embroidery machine includes a head housing 3, a needle bar holder 4, a thread clamping drive mechanism 1, and a thread clamping mechanism 2. The needle bar holder 4 is located on the front of the head housing 3, and a vertically extending needle bar 41 is mounted on the needle bar holder 4. An embroidery needle is mounted at the bottom end of the needle bar 41 for embroidery. In one embodiment, the embroidery machine performs multi-color embroidery; therefore, the needle bar holder 4 is equipped with multiple needle bars 41 arranged side-by-side, and a left-right extending slide rail 31 is provided on the front of the head housing 3. The needle bar holder 4 is slidably mounted on the slide rail 31, allowing the needle bar 41 to be replaced by lateral movement. In another embodiment, the embroidery machine performs single-color embroidery; therefore, the needle bar holder 4 is equipped with only one needle bar 41, and the needle bar holder 4 is fixedly or detachably connected to the head housing 3.

[0050] The head housing 3 is equipped with a vertically extending needle bar drive shaft 32. A needle bar connecting structure 33 is provided on the needle bar drive shaft 32. The needle bar connecting structure 33 is connected to the needle bar 41 on the needle bar frame 4, thereby driving the needle bar 41 to move up and down to perform embroidery.

[0051] The thread clamping mechanism 2 is provided on the needle bar holder 4 at the lower middle part corresponding to the needle bar 41, and the thread clamping drive mechanism 1 is provided on the machine head housing 3. The thread clamping drive mechanism 1 is used to drive the thread clamping mechanism 2 to move, so that the thread clamping mechanism 2 can clamp or release the embroidery thread. When the needle bar 41 is embroidering, the thread clamping mechanism 2 releases the embroidery thread, so that the embroidery thread can be fed to the embroidery needle from top to bottom for embroidery; when the needle bar 41 stops, the thread clamping mechanism 2 clamps the embroidery thread, thereby preventing the embroidery thread from being fed downward or jumping.

[0052] Reference Figure 3 , Figure 4The face thread clamping drive mechanism 1 includes a driver 11, a drive rod 12, and a transmission arm 13. The driver 11 is mounted on the head housing 3, and the drive rod 12 is mounted on the driver 11 and can extend and retract under the drive 11. The transmission arm 13 has a rotating connection part 133, which is rotatably connected to the head housing 3. The two ends of the rotating arm are respectively referred to as the first end 131 and the second end 132. The first end 131 is driven by the drive rod 12, and the second end 132 is used to drive the top rod 22 of the face thread clamping mechanism 2, which is described below. More specifically, the head housing 3 is a hollow shell with a bottom plate 3-1, two side plates 3-2, and a top frame structure. The bottom plate 3-1 and the two side plates 3-2 are generally flat, and the bottom plate 3-2 is inclined upward from front to back. The base plate 3-1 has a vertical shaft fixed near the front end. The rotating connection part 133 of the transmission arm 13 is sleeved on the shaft and can rotate around the shaft in the horizontal plane.

[0053] In existing technology, the transmission arm (electromagnet push rod or drive rod push plate) is directly fixed to the drive rod (iron core) of the driver (electromagnet). Since the transmission arm is inclined to the drive rod, the part of the transmission arm that acts on the push rod is not on the axis of the iron core. When pushing the push rod forward, the reaction force on the iron core or the radial component force along the iron core will generate frictional resistance when the drive rod is driven to move axially by the driver. This will affect the axial travel of the drive rod, increase the wear of the drive rod, make it more prone to bending and deformation, and may even cause the drive rod to get stuck and be unable to drive the push rod.

[0054] Therefore, to address this technical problem, the transmission arm 13 of this application utilizes the lever principle. During driving, the reaction force generated by the push rod 22 is transmitted to the first end 131 and applies a force to the drive rod 12. The direction of this force is perpendicular to the line connecting the first end 131 to the rotating connection 133, and the direction changes with the rotation of the transmission arm 13. However, the required stroke distance of the push rod 22 is relatively short, resulting in a small rotation amplitude of the transmission arm 13. Therefore, the angle between the direction of the force applied by the first end 131 to the drive rod 12 and the axial direction of the drive rod 12 is very small. That is, the radial component of the force generated by the first end 131 of the transmission arm 13 to the drive rod 12 is very small compared to the prior art, thus not affecting the axial movement of the drive rod 12. This avoids damage and jamming caused by excessive friction.

[0055] Since the needle bar connecting structure 33 on the needle bar drive shaft 32 needs to be able to connect or separate from the needle bar 41, a drive mechanism is also required inside the machine head housing 3 to drive the needle bar connecting structure 33 to connect or separate from the needle bar 41. A main shaft (not shown in the figure) is transversely arranged through the middle of the machine head housing 3. Therefore, the machine head housing 3 only has space on the left and right sides of the needle bar drive shaft 32 to install this drive mechanism. Figure 3 For example, the drive mechanism is located on the left side of the needle bar drive shaft 32 and is fixed to the side plate on the left side of the head housing 3. Therefore, there is only space on the right side of the needle bar drive shaft 32 to install the thread clamping drive mechanism 1. Of course, the two installation positions can be interchanged. The transmission arm 13 needs to have a certain length. If the length of the transmission arm 13 is too short, the space on one side of the needle bar drive shaft 32 is also extremely limited. Placing the first end 131, the second end 132, and the rotating connection part 133 of the transmission arm 13 all in the space on one side of the needle bar drive shaft 32 not only easily causes mechanical interference problems, but also makes assembly more troublesome.

[0056] Therefore, the needle bar drive shaft 32 is located between the first end 131 and the second end 132, that is, the first end 131 and the second end 132 are located on the left and right sides of the needle bar drive shaft 32, respectively.

[0057] First, it avoids placing the first end 131 and the second end 132 of the transmission arm 13 in the same narrow space, thereby eliminating the risk of mechanical interference.

[0058] Secondly, let F1 be the force acting on the first end 131, L1 be the lever arm between the first end 131 and the rotating connection 133, F2 be the force acting on the second end 132, and L2 be the lever arm between the second end 132 and the rotating connection 133. If the top rod 22 is to clamp or release the embroidery thread, there are minimum thresholds for the force acting on it and the axial movement distance. Correspondingly, the basic length of the transmission arm 13 is satisfied, so the sizes of L1 and L2 are also appropriately enlarged. When the axial movement distance of the top rod is not less than the minimum threshold, the rotation amplitude of the transmission arm 13 can be appropriately reduced, so that the direction of the force applied by the first end 131 to the drive rod 12 changes less, which can further improve the stability of the extension and retraction of the drive rod 12.

[0059] Furthermore, the rotating connection portion 133 and the first end portion 131 of the transmission arm 13 are located on the same side of the needle bar drive shaft 32, so as to... Figure 3For example, the rotating connection 133 is located on the right side of the needle bar drive shaft 32. After the length of the transmission arm 13 is determined, the size of L1 can be appropriately reduced, and the size of L2 can be appropriately increased. According to F1*L1=F2*L2, under the condition that F2 needs to meet the minimum threshold, increasing L2 and decreasing L1 will increase F1, which correspondingly increases the power strength requirement of the driver 11, which is acceptable for this application. The arc distance formed by the rotation of the first end 131 and the second end 132 around the rotating connection 133 is proportional to the size of L1 and L2. Therefore, correspondingly, the extension and retraction stroke of the drive rod 12 is also appropriately shortened, thereby shortening the overall length of the driver 11, which is very advantageous for optimizing the arrangement of the driver 11 in a narrow space.

[0060] The portion of the transmission arm 13 between the rotating connection 133 and the second end 132 has a curved section 13A that avoids the needle bar drive shaft 32. On the one hand, providing the curved section 13A can prevent mechanical interference between the transmission arm 13 and the needle bar drive shaft 32 when rotating; on the other hand, it can make the overall extension of the transmission arm 13 as far as possible along the left-right direction, so that the portion between the rotating connection 133 and the first end 131 is substantially perpendicular to the drive rod 12.

[0061] The driver 11 is an electromagnetic driver, and when the driver 11 is energized, it drives the drive rod 12 by magnetic force.

[0062] The lower part of the head housing 3 is provided with a mounting housing 3-3 for mounting the driver 11. Spatially, part of the driver is located inside the head housing 3, and another part is located outside the head housing 3. This not only effectively utilizes the space inside the head housing 3, but also avoids the mounting housing 3-3 occupying too much space outside the head housing 3, thus preventing the risk of mechanical interference. More specifically, the mounting housing 3-3 is recessed inward in the bottom plate of the head housing 3, so that part of the mounting housing 3-3 is inside the head housing 3, and another part is outside the head housing 3. The driver 11 is disposed inside the mounting housing 3-3. The front end face of the mounting housing 3-3 has an opening, allowing the drive rod 12 to extend out of the opening and drively connect with the first end 131 of the transmission arm 13. The mounting housing 3-3 can increase the assembly space of the driver 11, and only part of it is located outside the head housing 3, avoiding mechanical interference. Of course, the mounting housing 3-3 is detachable, either as a whole or partially, to facilitate the installation, maintenance, or replacement of the driver 11.

[0063] To ensure smooth extension and retraction of the drive rod 12 and minimize frictional resistance, the drive rod 12 is designed as a round rod, and no guide structure is provided between the drive rod 12 and the driver 11. Therefore, the drive rod 12 may rotate around its axis during extension and retraction. To avoid this, the rotation of the drive rod 12 around its axis needs to be restricted while it is being connected to the first end 131 of the transmission arm 13. Furthermore, due to the limited space, the disassembly of the drive rod 12 and the transmission arm 13 should be as convenient as possible.

[0064] Reference Figure 5 In the first embodiment, the transmission arm 13 has a sliding groove 13-j extending along the arm body near its first end 131, and the sliding groove 13-j has an opening at the first end 131, thus making the first end 131 of the transmission arm 13 present a double-forked structure. The drive rod 12 has a slotted structure 12-k formed at its end along its extension direction, and the transmission arm 13 is inserted into the slotted structure 12-k of the drive rod 12. The drive rod 12 is provided with a shaft 121, which can be a pin and passes through the sliding groove 13-j on the transmission arm 13, thereby realizing a transmission connection. Since the shaft 121 is inserted into the sliding groove 13-j, it also restricts the drive rod 12 to prevent it from rotating around the axis. The shaft 121 can be fixed to the drive rod 12, and during assembly and disassembly, the double-forked structure of the first end 131 of the transmission arm 13 can be inserted into or pulled out of the drive rod 12.

[0065] Reference Figure 6 In the second embodiment, the transmission arm 13 has a sliding groove 13-j extending along the arm body near the first end 131, and this sliding groove 13-j is a closed groove. The drive rod 12 has a slotted structure 12-k formed from its end along its extending direction. The transmission arm 13 is inserted into the slotted structure 12-k of the drive rod 12. The drive rod 12 is provided with a shaft 121, which can be a pin and passes through the sliding groove 13-j on the transmission arm 13, thereby realizing the transmission connection. The shaft 121 is detachably connected to the drive rod 12. During assembly and disassembly, the shaft 121 is removed to separate the transmission arm 13 and the drive rod 12.

[0066] Reference Figure 7In the third embodiment, the transmission arm 13 has a sliding groove 13-j extending along the arm body near the first end 131, and this sliding groove 13-j is a closed groove. The transmission arm 13 and the drive rod 12 are arranged intersectingly. The drive rod 12 is provided with a shaft 121, which can be a pin and passes through the sliding groove 13-j on the transmission arm 13 to achieve a transmission connection. The shaft 121 is detachably connected to the drive rod 12. During assembly and disassembly, the shaft 121 can be removed to separate the transmission arm 13 and the drive rod 12.

[0067] These three implementations all share the common feature of using a shaft 121 passing through a sliding groove 13-j to restrict the drive rod 12. The difference lies in the method of disassembling the drive rod 12 and the transmission arm 13. Alternatively, the sliding groove 13-j can be made open at its first end 131, allowing the transmission arm 13 to be inserted and removed from the drive rod 12. Or, the sliding groove 13-j can be made closed, allowing the shaft 121 to be detachably connected to the drive rod 12. Of course, both of these detachable structures can coexist.

[0068] Reference Figures 9-11 The thread clamping mechanism 2 includes a thread clamping plate 21, a top rod 22, a thread clamping piece 23, and a thread guiding structure 24. The thread clamping plate 21 is disposed on the front side of the needle bar frame 4. The top rod 22 is horizontally disposed and passes through the needle bar frame 4 and the thread clamping plate 21. The front end of the top rod 22 is fixedly connected to the thread clamping piece 23. The top rod 22 can reciprocate along its axial direction, thereby allowing the thread clamping piece 23 to conform to or move away from the front side of the thread clamping plate 21. The thread guiding structure 24 is disposed on the front side of the thread clamping plate 21 and has a thread groove 24a that allows the embroidery thread to pass vertically, thereby limiting the position of the embroidery thread and preventing the thread from shaking during embroidery. When the embroidery machine is embroidering, the top rod 22 moves forward, and the thread clamping piece 23 and the thread clamping plate 21 separate to release the embroidery thread so that it can be conveyed downward; when the embroidery machine stops embroidering or the current needle bar stops, the top rod 22 moves backward, and the thread clamping piece 23 adheres to the thread clamping plate 21 to hold the embroidery thread.

[0069] The thread clamping mechanism also includes an elastic reset structure 25, which drives the top rod 22 to reset so that the thread clamping piece 23 and the thread clamping plate 21 clamp the embroidery thread. More specifically, the elastic reset mechanism uses a reset spring, and a stop structure 21 is provided on the top rod 22. The reset spring is sleeved on the part of the top rod 22 located between the stop structure 21 and the thread clamping plate 21, so that the two ends of the reset spring are supported on the stop structure 21 and the thread clamping plate 21 respectively.

[0070] During embroidery, the push rod 22 is pushed forward by the second end 132 to release the embroidery thread. At this time, the return spring is in a compressed state. When the needle stops, the push rod 22 is not subject to the force of the second end 132 and is reset under the elastic force of the return spring to hold the embroidery thread.

[0071] Reference Figure 8 and combined Figure 10 The needle bar holder 4 has a thread take-up lever 42 on its upper part for guiding the embroidery thread; the thread take-up lever 42 and the top lever 22 are located on the same side of the needle bar 41. Since the thread take-up lever 42 can only be set on one side of the needle bar 41, the part of the embroidery thread from the thread take-up lever 41 to the top thread clamping mechanism 2 is not vertical, but slightly inclined. When the embroidery thread is clamped, the mechanical vibration of the embroidery machine can easily cause the embroidery thread to gradually jump off in the inclined direction. By setting the top lever 22 and the thread take-up lever 42 on the same side of the needle bar, the part where the top lever 22 and the top thread clamping plate 23 are connected is in the direction of the embroidery thread jumping off. Since the part where the top thread clamping plate 23 and the top lever 22 are connected is the part where the top thread clamping plate 23 and the top thread clamping plate 21 are clamped most tightly, the jumping off of the embroidery thread can be avoided.

[0072] The thread clamping piece 23 is provided with a through-hole limiting groove 23-1, through which the thread guiding structure 24 passes. When the top rod 22 moves along its axial direction, the thread guiding structure 24 and the limiting groove 23-1 will slide relative to each other, so that the thread clamping piece 23 is always in a restricted state, preventing the thread clamping piece 23 from rotating around the top rod 22, and ensuring that the embroidery thread is not disturbed during the embroidery process.

[0073] The wire guiding structure 24 includes a first arm 241 and a second arm 242 spaced apart from each other, forming the wire guiding groove 24a between the first arm 241 and the second arm 242. Both the first arm 241 and the second arm 242 pass through the limiting groove 23-1. The first arm 241 is longer than the second arm 242, and within the normal working stroke range of the push rod 22 moving along its axial direction, the first arm 241 always remains in the state of passing through the limiting groove 23-1. The function of the first arm 241 is to keep the wire guiding structure 24 always within the limiting range of the limiting groove 23-1, preventing the wire guiding structure 24 from detaching from the surface wire clamping piece 23.

[0074] In existing technologies, embroidery threads pass through the thread clamping structure from top to bottom, such as CN209602790U, where the thread passes through the thread guide sleeve and into the thread clamping seat. This threading method is relatively cumbersome to operate, and it further increases the difficulty of operation when the embroidery thread material is relatively soft. To solve this technical problem, in this application, the length of the second arm 242 is shorter than that of the first arm 241, and when the top rod 22 moves forward along the axial direction, the thread clamping piece 23 separates from the end of the second arm 242, forming a gap between them. This allows the embroidery thread to fall from outside the thread guide structure 24 into the thread guide groove 24a. That is, in this embodiment, the difficulty of operation can be reduced. Afterwards, when the top rod 22 is in its working state, the thread guide groove 24a is always in a closed state due to the blocking effect of the thread clamping piece 23, and the embroidery thread is restricted within the thread guide groove 24a.

[0075] Alternatively, the top rod 22 moves forward axially, and the second arm 4 does not disengage from the space defined by the limiting groove 23-1. That is, from a top view, the second arm 4 is not separated from the thread clamping piece 23, and gaps can be formed between the second arm 242 and the four groove walls of the limiting groove 23-1. There are several scenarios: First, the second arm 242 does not contact the groove wall of the limiting groove 23-1. Since the embroidery thread is a flexible material, it adheres to the second arm 242. Due to the gap, the embroidery thread can be inserted into the thread guide groove 24a from outside the thread guide structure 24 along the end of the second arm 242. Second, there is a gap between the second arm 242 and one of the upper and lower groove walls of the limiting groove 23-1, while the thread clamping piece 23 and the top rod 22 are not completely fixed. A certain degree of relative movement can occur between them, thus creating a gap between the second arm 242 and the other groove wall when the embroidery thread is inserted, allowing the embroidery thread to be inserted into the thread guide groove 24a.

[0076] To make it easier for the embroidery thread to fall from the thread guide structure 24 into the thread guide groove 24a, a slope surface 2421 that gradually converges toward the end of the second arm 242 is formed on the side of the second arm 242 away from the thread guide groove 24a, and the end of the second arm 242 is presented as a hook shape that bends toward the thread guide groove 24a.

[0077] The front of the face thread clamping plate 21 is provided with an inwardly recessed positioning groove 21-1. Since multiple top rods 22 and face thread clamping pieces 23 share a face thread clamping plate 21, the positioning groove 21-1 extends along the direction of the face thread clamping plate 21 and has a straight groove structure. The function of the positioning groove 21-1 is to position the thread passing structure 24. The roots of the first support arm 241 and the second support arm 242 are embedded in the positioning groove 21-1 and fixed on the face thread clamping plate 21.

[0078] The thread guide structure 24 also includes a handle 243, which connects to the roots of the first support arm 241 and the second support arm 242, giving the thread guide structure 24 a U-shaped structure. The handle 243 is embedded in the positioning groove 21-1 and fixed to the front of the thread clamping plate 21. More specifically, the handle 243 has a plug structure that passes through the thread clamping plate 21 to fix the thread guide structure 24 to the thread clamping plate 21. There are many ways to fix the thread guide structure 24 to the thread clamping plate 21; adhesive can also be used to attach the handle 243 and the roots of the first support arm 241 and the second support arm 242 to the positioning groove 21-1.

[0079] The lead-through structure 24 is made of ceramic or hardened steel, which gives it a smooth and wear-resistant property, extending its service life and reducing replacement costs.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An embroidery machine, characterized in that, The embroidery machine includes a head housing, a needle bar holder mounted on the front of the head housing, a thread clamping drive mechanism, and a thread clamping mechanism. The needle bar holder has vertically extending needle bars. The thread clamping drive mechanism includes a driver, a drive rod, and a transmission arm. The driver is mounted on the head housing of the embroidery machine. The drive rod is telescopically movable under the drive. The transmission arm has a rotating connection and is rotatably connected to the head housing of the embroidery machine. The first end of the transmission arm is driven by the drive rod. The second end of the transmission arm is used to drive the top rod of the thread clamping mechanism. The thread clamping mechanism includes a thread clamping plate, a top rod, a thread guide structure, and a thread clamping piece. The thread clamping plate is disposed on the front side of the needle bar frame. The thread guide structure is disposed on the front side of the thread clamping plate and has a thread guide groove that allows the embroidery thread to pass through. The top rod passes through the needle bar frame and the thread clamping plate. The front end of the top rod is provided with the thread clamping piece, and the rear end is driven by the second end of the transmission arm. The top rod can move axially, so that the thread clamping piece and the thread clamping plate clamp or release the embroidery thread. The thread clamping piece has a limiting groove through which the thread guiding structure passes, preventing the thread clamping piece from rotating around the top rod; the thread guiding structure includes a first arm and a second arm spaced apart from each other, forming the thread guiding groove between them; within the normal working stroke range of the top rod moving axially, the first arm always remains in the state of passing through the limiting groove; the top rod moves forward axially, and the thread clamping piece and the second arm separate, forming a gap between them, so that the embroidery thread falls from outside the thread guiding structure into the thread guiding groove; or, the top rod moves forward axially, and the second arm does not disengage from the space defined by the limiting groove, and the second arm and the four groove walls of the limiting groove form gaps, so that the embroidery thread is hooked into the thread guiding groove from outside the thread guiding structure along the end of the second arm; the upper part of the needle bar is provided with a thread take-up rod for guiding the embroidery thread; the thread take-up rod and the top rod are located on the same side of the needle bar; the side of the second arm away from the thread guiding groove forms a slope surface that gradually converges towards the end of the second arm.

2. The embroidery machine according to claim 1, characterized in that, The second end of the transmission arm is used to push the top rod to move forward along the axial direction so that the top thread clamping piece and the top thread clamping plate release the embroidery thread; the top rod is provided with an elastic reset structure for driving the top rod to reset so that the top thread clamping piece and the top thread clamping plate clamp the embroidery thread.

3. The embroidery machine according to claim 1, characterized in that, The wire-passing structure is configured as a component made of ceramic or hardened steel.

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