Thread adjusting device of sewing machine and sewing method applying thread adjusting device

Abstract

The invention discloses a thread adjusting device of a sewing machine and a sewing method applying the thread adjusting device, and aims to provide the thread adjusting device which can adjust thread tension in time according to needs in the working process of the sewing machine; according to the thread adjusting device and the sewing method using the thread adjusting device, the thread ends can be cut, the cut thread ends can be pulled out from the bottom of sewing materials after sewing is completed, and the thread pulling amount can be adjusted. A thread adjusting device of a sewing machine comprises a support; the thread picking plate is rotationally arranged on the bracket through a supporting shaft; the thread adjusting and passing channel comprises two threading holes formed in the support and an adjusting hole formed in the thread picking plate, and the thread picking plate is located between the two threading holes; the take-up plate driving mechanism comprises a driving motor for driving the take-up plate to rotate; a sewing thread of the sewing machine sequentially passes through one threading hole, the adjusting hole and the other threading hole; the thread take-up plate driving mechanism drives the thread take-up plate to rotate so as to adjust the friction resistance of a sewing thread passing through the thread adjusting and passing channel in the working process of the sewing machine.

Description

Technical Field

[0001] This invention relates to the field of sewing technology, and more specifically to a thread adjusting device for a sewing machine and a sewing method using the thread adjusting device. Background Technology

[0002] In the application scenarios of sewing machines, the stitching stability in different directional ranges is affected by the change in the feed direction of the fabric during the stitching process of the needle and looper. It is necessary to solve the problem of adjusting the thread tension in different sections in this scenario.

[0003] When sewing machines encounter different working scenarios and sewing conditions of varying thicknesses, it is necessary to adjust the thread tension during the sewing process accordingly, increasing or decreasing the thread tension when sewing thick or thin materials. This will allow the looper to be tightened perfectly for both thick and thin materials, resulting in more perfect and even sewing stitches.

[0004] In addition, in some usage scenarios, after sewing is completed, it is necessary to quickly pull the thread back so that the cut thread ends can be pulled out from the bottom of the fabric. At this time, a wide range of thread supply variation is required, and the amount of thread pulled can be adjusted so that after pulling the thread, the thread ends can be smoothly pulled out from the bottom of the fabric, and the length of the thread ends remaining on the needle can be controlled to facilitate the next normal sewing.

[0005] In existing sewing machines, although the thread tension can be adjusted by the thread tensioner, the thread tension cannot be adjusted in a timely manner during the sewing process, making it difficult to adapt to different working scenarios. It also cannot quickly pull the thread back after sewing to remove the cut thread from the bottom of the fabric, and control the length of the thread remaining on the needle for the next normal sewing.

[0006] For example, Chinese Patent Publication No. CN107034596A, an invention entitled "A Dual Tension Thread Gripper", includes a thread gripper with four sets of grippers: a first coarse adjustment thread gripper, a second coarse adjustment thread gripper, a first fine adjustment thread gripper, and a second fine adjustment thread gripper. It allows the thread tension to be adjusted by combining coarse and fine adjustments. However, it also has the problem that the thread tension cannot be adjusted in a timely manner during the sewing process of the sewing machine, making it difficult to adapt to different working scenarios. Summary of the Invention

[0007] The purpose of this invention is to provide a sewing machine thread adjustment device and a sewing method using the same device. The thread adjustment device can not only adjust the thread tension as needed during the sewing machine operation, but also pull the cut thread end from the bottom of the fabric after sewing is completed. The amount of thread pulled can be adjusted so that the thread end can be smoothly pulled out from the bottom of the fabric after pulling the thread, and the length of the thread end remaining on the needle can be controlled to facilitate the next normal sewing.

[0008] The technical solution of this invention is: A thread adjusting device for a sewing machine, comprising: support; The cable tray is rotatably mounted on the bracket via a support shaft; The cable guide includes two threading holes on the bracket and an adjustment hole on the cable take-up plate, with the cable take-up plate located between the two threading holes; The thread-picking board drive mechanism includes a drive motor that drives the thread-picking board to rotate; The sewing machine thread passes sequentially through one thread hole, an adjustment hole, and another thread hole. A thread take-up plate drive mechanism rotates the thread take-up plate to adjust the frictional resistance of the thread passing through the thread guide during sewing machine operation. The specific operation of the thread adjusting device in this sewing machine is as follows: the drive motor of the thread take-up plate drive mechanism drives the thread take-up plate to rotate, and the rotation angle of the thread take-up plate can be controlled by the rotation angle of the drive motor to adjust the amount of thread supplied and the magnitude of frictional resistance passing through the thread guide, thereby achieving the requirement of adjusting the thread tension. Thus, on the one hand, during the sewing machine's operation, the rotation angle of the take-up plate can be adjusted and controlled by the drive motor to regulate the frictional resistance of the thread passing through the thread guide, thereby adjusting the thread tension as needed to adapt to different application and work scenarios during the sewing machine's operation and improve the quality of the sewing stitches. On the other hand, after sewing is completed, the rotation angle of the take-up plate can be adjusted and controlled by the drive motor to pull the cut thread end from the bottom of the fabric, and the amount of thread pulled can be adjusted to ensure that the thread end can be smoothly pulled out from the bottom of the fabric after pulling the thread, and the length of the thread end remaining on the needle can be controlled to facilitate the next normal sewing.

[0009] Preferably, the mechanism also includes a swing arm pressing mechanism, which comprises: The swing arm has one end rotatably mounted on a support shaft; The pressure roller is rotatably located at the other end of the swing arm, and the pressure roller is located inside the adjustment hole; A stopper is provided on the line take-up plate; The first elastic element, the swing arm abuts against the stop under the action of the first elastic element, at this time there is a gap between the pressure roller and the sewing thread passing through the adjustment hole; The limiting component is located on the bracket or between the bracket and the swing arm; In the process of the thread take-up plate drive mechanism driving the thread take-up plate to rotate, thereby increasing the frictional resistance of the thread passing through the thread guide, when the rotation angle of the thread take-up plate reaches the set angle, the limiting component will restrict the rotation of the swing arm, causing the pressure roller to gradually approach the thread and press the thread tightly between the pressure roller and the inner wall of the adjusting hole. While using the rotating thread take-up plate to adjust the frictional resistance of the thread passing through the thread guide to regulate thread tension, as the rotation angle of the thread take-up plate increases, the curvature of the thread passing through the thread guide intensifies (the thread forms a V-shape), increasing the frictional resistance. Thus, during sewing, the thread is prone to breakage at the edge of the thread hole or the edge of the adjusting hole. To solve this problem, this solution incorporates a swing arm thread pressing mechanism, which can achieve a larger amount of thread tension adjustment while effectively controlling and reducing the rotation angle of the thread take-up plate. Specifically… When the rotation angle of the thread take-up plate is less than the set angle, during the process of the thread take-up plate drive mechanism driving the thread take-up plate to rotate, the swing arm abuts against the stop under the action of the first elastic element. The swing arm and the thread take-up plate rotate synchronously, and there is a gap between the pressure roller and the sewing thread passing through the adjustment hole. That is, when the rotation angle of the thread take-up plate is less than the set angle, the swing arm thread pressing mechanism does not work. Only by rotating the thread take-up plate can the frictional resistance of the sewing thread passing through the thread adjustment channel be adjusted to adjust the thread tension.

[0010] When the thread take-up plate rotates to the set angle, the limiting component restricts the rotation of the swing arm. Subsequently, as the rotation angle of the thread take-up plate increases, the pressure roller on the swing arm gradually approaches the thread and presses the thread between the pressure roller and the inner wall of the adjustment hole. By pressing the thread against the inner wall of the adjustment hole with the pressure roller, the thread tension is quickly increased, thereby rapidly increasing the thread tension. Therefore, when the rotation angle of the thread take-up plate reaches the set angle and the rotation angle of the thread take-up plate is increased, the adjustment amount of the thread tension can be quickly increased. This achieves a large adjustment amount of thread tension while effectively controlling the reduction of the rotation angle of the thread take-up plate, thereby effectively avoiding the problem of the thread breaking at the edge of the thread hole or the edge of the adjustment hole due to excessive rotation angle of the thread take-up plate, which would cause the thread to bend too violently after passing through the thread adjustment channel.

[0011] Preferably, the limiting member is fixedly mounted on the bracket, and the limiting member is located on the same side as the stop member on the swing arm. In this way, when the swing arm rests against the limiting member and the pressure roller presses the thread against the inner wall of the adjusting hole, the thread take-up plate will stop rotating. This avoids the thread take-up plate rotating too much, which would cause the thread to bend too drastically after passing through the thread adjustment channel, resulting in the thread breaking at the edge of the thread hole or the edge of the adjusting hole.

[0012] Preferably, the limiting element is an elastic element connected between the bracket and the swing arm. The elastic element is a tension spring or rubber band, which provides elastic force to cause the swing arm to drive the pressure roller closer to the thread passing through the adjustment hole. Thus, when the thread take-up plate rotates to the set angle, the elastic element will overcome the force of the first elastic element and limit the rotation of the swing arm; causing the pressure roller on the swing arm to gradually approach the thread and press the thread between the pressure roller and the inner wall of the adjustment hole; after the pressure roller presses the thread against the inner wall of the adjustment hole, the drive motor can continue to drive the thread take-up plate to rotate a certain angle, thereby gradually increasing the pressing force of the pressure roller on the thread.

[0013] Preferably, the thread-picking plate drive mechanism also includes: A sliding member is slidably mounted on the bracket. The sliding member is provided with a drive pin. The wire take-up plate has a strip-shaped hole extending radially along the support shaft, and the drive pin extends into the strip-shaped hole. The rack and gear mesh with each other, with the rack fixed on the sliding component. The drive motor drives the gear to rotate. In actual operation, the drive motor drives the gear to rotate, which in turn drives the rack, sliding component, and drive pin to translate. The drive pin slides within the slotted hole and drives the take-up plate to rotate around the support shaft, thereby adjusting the rotation angle of the take-up plate.

[0014] Preferably, the take-up plate has a strip plate extending radially along the support shaft, the strip plate has holes, the gear is located below the rack, and the drive motor is located below the support shaft. This facilitates the arrangement of the drive motor, gear, and rack.

[0015] Preferably, the adjustment hole is arc-shaped and extends circumferentially around the support shaft.

[0016] Preferably, a thread tensioner is also included. The thread tensioner comprises two pressure plates and a threaded adjustment knob. The adjustment knob adjusts the clamping force between the two pressure plates. The sewing thread first passes between the two pressure plates and then through the thread guide. Thus, before the sewing machine starts operating, the clamping force between the two pressure plates can be adjusted using the adjustment knob of the thread tensioner to initially adjust the thread tension. During sewing machine operation, the thread tension is fine-tuned by controlling the rotation angle of the take-up plate via the drive motor, thereby improving the accuracy of thread tension control.

[0017] Preferably, the bracket includes a mounting base and a wire guide plate, with the wire guide plate located between the mounting base and the wire guide plate. One of the two wire-passing holes is located on the mounting base, and the other is located on the wire guide plate. The support shaft is located on the mounting base. This facilitates actual processing and manufacturing.

[0018] A sewing method, employing a thread adjusting device of a sewing machine, includes the following steps: Divide the sewing stitches into several sewing sections and set the thread tension for each sewing section. During the sewing process, the thread take-up plate of the thread adjusting device is driven by a set angle to rotate the thread take-up plate, adjusting the thread tension of each sewing section to the set value. In this way, the thread tension can be adjusted as needed during sewing to adapt to different application and work scenarios, thereby improving the quality of the sewing stitches.

[0019] The beneficial effects of this invention are as follows: On the one hand, during the operation of the sewing machine, the rotation angle of the take-up plate can be adjusted and controlled by the drive motor to adjust the frictional resistance of the thread passing through the thread guide, thereby adjusting the thread tension as needed to adapt to different application and work scenarios during the sewing machine operation and improve the quality of the sewing stitches; on the other hand, after sewing is completed, the rotation angle of the take-up plate can be adjusted and controlled by the drive motor to pull the cut thread end from the bottom of the fabric, and the amount of thread pulled can be adjusted so that after pulling the thread, the thread end can be smoothly pulled out from the bottom of the fabric, and the length of the thread end remaining on the needle can be controlled, which facilitates the next normal sewing. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a thread adjusting device for a sewing machine under a certain state, according to the present invention.

[0021] Figure 2 This is a schematic diagram of another state of the thread adjusting device of a sewing machine according to the present invention.

[0022] Figure 3 This is a schematic diagram of a swing arm pressing mechanism in a specific embodiment three of the present invention.

[0023] Figure 4 This is a schematic diagram of a swing arm pressing mechanism in a specific embodiment of the present invention.

[0024] In the picture: Bracket 1, mounting base 1.1, cable guide plate 1.2; Wire guide plate 2, strip hole 2.1; Adjustment hole 3, wire guide 3.1, adjustment hole 3.2; 4 stitches; Support shaft 5; The thread-picking plate drive mechanism 6, drive motor 6.1, sliding component 6.2, drive pin 6.3, gear 6.4, rack 6.5; Wire clamp 7; The swing arm pressing mechanism consists of a swing arm (8.1), a pressing roller (8.2), a stop (8.3), a limiting rod (8.4), and an elastic element (8.5). Detailed Implementation

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments: Specific Implementation Example 1, such as Figure 1 As shown, a thread guide device for a sewing machine includes a bracket 1, a thread take-up plate 2, a thread guide 3, and a thread take-up plate drive mechanism 6. The bracket 1 is fixedly installed; for example, the bracket 1 is fixedly installed on the frame of the sewing machine, or the bracket 1 is a part of the frame of the sewing machine. In this embodiment, the bracket 1 is manufactured separately and fixedly connected to the frame of the sewing machine.

[0026] The thread-lifting plate 2 is rotatably mounted on the bracket 1 via the support shaft 5.

[0027] The thread-picking board driving mechanism 6 includes a drive motor 6.1, which drives the thread-picking board 2 to rotate. In this embodiment, as shown... Figure 1 As shown, the thread take-up plate 2 includes an initial state. The initial state of the thread take-up plate 2 refers to the state in which the thread take-up plate drive mechanism 6 drives the thread take-up plate 2 to rotate, so that the thread take-up plate 2 is in the initial state. At this time, the sewing thread 4 that has passed through the thread guide 3 extends in a straight line. Figure 1 The thread-drawing board 2 is in its initial state.

[0028] The thread guide 3 includes two thread holes 3.1 on the support 1 and an adjustment hole 3.2 on the take-up plate 2. The take-up plate 2 is located between the two thread holes 3.1. The sewing thread 4 of the sewing machine passes through one of the thread holes 3.1, the adjustment hole 3.2, and the other thread hole 3.1 in sequence. The take-up plate drive mechanism 6 drives the take-up plate 2 to rotate, thereby adjusting the frictional resistance of the sewing thread 4 passing through the thread guide 3 during the operation of the sewing machine.

[0029] The specific operation of the thread adjusting device of a sewing machine in this embodiment is as follows: Figure 1 , Figure 2 As shown, the thread take-up plate 2 is driven to rotate by the drive motor 6.1 of the thread take-up plate drive mechanism 6. The rotation angle of the thread take-up plate 2 can be controlled by the rotation angle of the drive motor 6.1, thereby adjusting the amount of thread 4 supplied and the magnitude of frictional resistance after passing through the thread guide 3, thus achieving the requirement of adjusting the thread tension. In this way, on the one hand, during the sewing machine's operation, the rotation angle of the thread take-up plate 2 can be adjusted and controlled by the drive motor 6.1 to adjust the magnitude of frictional resistance of the thread 4 after passing through the thread guide 3, thereby achieving timely adjustment of thread tension as needed to adapt to different application scenarios and work conditions during the sewing machine's operation, improving the quality of the sewing stitches; on the other hand, after sewing is completed, the rotation angle of the thread take-up plate 2 can be adjusted and controlled by the drive motor 6.1 to pull the cut thread end from the bottom of the fabric. The amount of thread pulled is adjustable, ensuring that after pulling the thread 4, the thread end can be smoothly pulled out from the bottom of the fabric, and the length of the thread end remaining on the needle can be controlled, facilitating the next normal sewing.

[0030] Specific embodiment two, such as Figure 1 As shown, a thread guide device for a sewing machine includes a bracket 1, a thread take-up plate 2, a thread guide 3, and a thread take-up plate drive mechanism 6. The bracket 1 is fixedly installed; for example, the bracket 1 is fixedly installed on the frame of the sewing machine, or the bracket 1 is a part of the frame of the sewing machine. In this embodiment, the bracket 1 is manufactured separately and fixedly connected to the frame of the sewing machine.

[0031] The thread-lifting plate 2 is rotatably mounted on the bracket 1 via the support shaft 5.

[0032] The thread-picking board drive mechanism 6 includes a drive motor 6.1, which drives the thread-picking board 2 to rotate.

[0033] In one embodiment, such as Figure 1 As shown, the thread-taking plate drive mechanism 6 also includes a sliding member 6.2 and a meshing rack 6.5 and gear 6.4. The sliding member 6.2 is slidably mounted on the bracket 1. The sliding direction of the sliding member 6.2 is perpendicular to the support shaft 5. A drive pin 6.3 is provided on the sliding member 6.2, and the drive pin 6.3 is parallel to the support shaft 5. The thread-taking plate 2 has a strip-shaped hole 2.1 extending radially along the support shaft 5. The drive pin 6.3 extends into the strip-shaped hole 2.1. The rack 6.5 is parallel to the sliding direction of the sliding member 6.2. The rack 6.5 is fixed on the sliding member 6.2. The drive motor 6.1 drives the gear 6.4 to rotate. In actual operation, the drive motor 6.1 drives the gear 6.4 to rotate, and the drive gear 6.4 drives the rack 6.5, the sliding member 6.2, and the drive pin 6.3 to translate. The drive pin 6.3 slides in the strip-shaped hole and drives the thread-taking plate 2 to rotate around the support shaft 5, thereby adjusting the rotation angle of the thread-taking plate 2.

[0034] Furthermore, the lead plate 2 is provided with a strip plate extending radially along the support shaft 5, and strip holes are provided on the strip plate. The gear 6.4 is located below the rack 6.5, and the drive motor 6.1 is located below the support shaft 5. This facilitates the arrangement of the drive motor 6.1, the gear 6.4, and the rack 6.5.

[0035] In another embodiment, the thread-taking plate drive mechanism 6 further includes a gear transmission mechanism or a synchronous belt transmission mechanism, with the thread-taking plate 2 fixedly connected to the support shaft 5. The drive motor 6.1 is connected to the support shaft 5 via the aforementioned gear transmission mechanism or synchronous belt transmission mechanism (not shown in the figure). In actual operation, the drive motor 6.1 drives the thread-taking plate 2 to rotate around the support shaft 5 via the gear transmission mechanism or synchronous belt transmission mechanism, thereby adjusting the rotation angle of the thread-taking plate 2.

[0036] The thread guide 3 includes two thread holes 3.1 on the support 1 and an adjustment hole 3.2 on the thread take-up plate 2. In this embodiment, the adjustment hole 3.2 is arc-shaped and extends circumferentially around the support shaft 5. Of course, the adjustment hole 3.2 can also be a round hole, a square hole, or other irregularly shaped hole. The thread take-up plate 2 is located between the two thread holes 3.1. The sewing thread 4 of the sewing machine passes through one of the thread holes 3.1, the adjustment hole 3.2, and the other thread hole 3.1 in sequence. The thread take-up plate drive mechanism 6 drives the thread take-up plate 2 to rotate to adjust the frictional resistance of the sewing thread 4 passing through the thread guide 3 during the operation of the sewing machine.

[0037] In this embodiment, as Figure 1 As shown, the thread take-up plate 2 includes an initial state. The initial state of the thread take-up plate 2 refers to the state in which the thread take-up plate drive mechanism 6 drives the thread take-up plate 2 to rotate, so that the thread take-up plate 2 is in the initial state. At this time, the sewing thread 4 that has passed through the thread guide 3 extends in a straight line. Figure 1 The thread-drawing board 2 is in its initial state.

[0038] The specific operation of the thread adjusting device of a sewing machine in this embodiment is as follows: Figure 1 , Figure 2 As shown, the thread take-up plate 2 is driven to rotate by the drive motor 6.1 of the thread take-up plate drive mechanism 6. The rotation angle of the thread take-up plate 2 can be controlled by the rotation angle of the drive motor 6.1, thereby adjusting the amount of thread 4 supplied and the magnitude of frictional resistance after passing through the thread guide 3, thus achieving the requirement of adjusting the thread tension. In this way, on the one hand, during the sewing machine's operation, the rotation angle of the thread take-up plate 2 can be adjusted and controlled by the drive motor 6.1 to adjust the magnitude of frictional resistance of the thread 4 after passing through the thread guide 3, thereby achieving timely adjustment of thread tension as needed to adapt to different application scenarios and work conditions during the sewing machine's operation, improving the quality of the sewing stitches; on the other hand, after sewing is completed, the rotation angle of the thread take-up plate 2 can be adjusted and controlled by the drive motor 6.1 to pull the cut thread end from the bottom of the fabric. The amount of thread pulled is adjustable, ensuring that after pulling the thread 4, the thread end can be smoothly pulled out from the bottom of the fabric, and the length of the thread end remaining on the needle can be controlled, facilitating the next normal sewing.

[0039] Furthermore, such as Figure 1As shown, a thread tensioning device for a sewing machine also includes a thread clamp 7. The thread clamp 7 is fixed on a bracket 1 or the frame of the sewing machine. The thread clamp 7 includes two pressure plates and a threaded adjustment knob. The adjustment knob adjusts the clamping force between the two pressure plates. The sewing thread 4 of the sewing machine first passes between the two pressure plates and then passes through the thread guide 3. The specific installation method and structure of the thread clamp are existing technologies, and this structure is not the inventive point of this application. Therefore, this application will not elaborate on the specific installation method and structure of the thread clamp and other conventional technical means. Thus, before the sewing machine starts working, the clamping force between the two pressure plates can be adjusted by adjusting the adjustment knob of the thread clamp to initially adjust the thread tension of the sewing thread 4; during the operation of the sewing machine, the rotation angle of the take-up plate 2 is controlled by the drive motor 6.1 to fine-tune the thread tension, thereby improving the control accuracy of the thread tension.

[0040] Furthermore, such as Figure 1 As shown, the bracket 1 includes a mounting base 1.1 and a wire guide plate 1.2. A wire guide plate 2 is located between the mounting base 1.1 and the wire guide plate 1.2. One of the two wire holes 3.1 is located on the mounting base 1.1, and the other wire hole 3.1 is located on the wire guide plate 1.2. A support shaft 5 is mounted on the mounting base 1.1. This design facilitates actual manufacturing.

[0041] Furthermore, the swing arm thread pressing mechanism 8 in this embodiment also includes a front limit member and a rear limit member, which are fixed to the bracket 1 or the frame of the sewing machine. The thread take-up plate 2 is located between the front limit member and the rear limit member to limit the rotation angle of the thread take-up plate 2. When the thread take-up plate 2 abuts against the front limit member, the thread take-up plate 2 is in its initial state.

[0042] In this specific embodiment, the remaining structure is the same as in specific embodiment one or specific embodiment two, except that... like Figure 3 As shown, a thread adjusting device for a sewing machine further includes a swing arm thread pressing mechanism 8. The swing arm thread pressing mechanism 8 includes a swing arm 8.1, a pressure roller 8.2, a stop 8.3, a first elastic element, and a limiting element. In this embodiment, the adjusting hole 3.2 is arc-shaped and extends circumferentially around the support shaft 5, or the adjusting hole 3.2 is an oval hole, or the adjusting hole 3.2 is a round hole.

[0043] One end of the swing arm 8.1 is rotatably mounted on the support shaft 5. The swing arm 8.1 extends radially along the support shaft 5.

[0044] The pressure roller 8.2 is rotatably mounted at the other end of the swing arm 8.1, and is located inside the adjustment hole 3.2. The sewing thread 4 passing through the adjustment hole 3.2 is located on one side of the pressure roller 8.2.

[0045] The stop 8.3 is provided on the thread take-up plate 2. In this embodiment, the stop 8.3 is composed of a stop rod or a stop block. The stop 8.3 is located on one side of the swing arm 8.1, and the sewing thread 4 passing through the adjustment hole 3.2 is located on the other side of the swing arm 8.1.

[0046] The swing arm 8.1 rests against the stop 8.3 under the action of the first elastic element. At this time, there is a gap between the pressure roller 8.2 and the seam 4 passing through the adjustment hole 3.2. In this embodiment, the first elastic element is a torsion spring, which is sleeved on the support shaft 5. One end of the torsion spring rests against the swing arm 8.1, and the other end of the torsion spring rests against the bracket 1.

[0047] A limiting member is disposed on the bracket 1 or between the bracket 1 and the swing arm 8.1. The limiting member is used to limit the rotation angle of the swing arm 8.1. In this embodiment, the limiting member is fixedly disposed on the bracket 1, and the limiting member is located on the same side of the stop 8.3 as the swing arm 8.1. The limiting member is a limiting rod 8.4 or a limiting block, etc.

[0048] During the process of the thread take-up plate drive mechanism 6 driving the thread take-up plate 2 to rotate in order to increase the frictional resistance of the sewing thread 4 passing through the thread adjustment channel 3, when the rotation angle of the thread take-up plate 2 reaches the set angle, the limiting member will restrict the rotation of the swing arm 8.1, so that the pressure roller 8.2 gradually approaches the sewing thread 4 and presses the sewing thread 4 between the pressure roller 8.2 and the inner wall of the adjustment hole 3.2.

[0049] In this embodiment, during the process of the thread take-up plate driving mechanism 6 driving the thread take-up plate 2 to rotate from the initial state, when the rotation angle of the thread take-up plate 2 is less than the set angle, during the process of the thread take-up plate driving mechanism 6 driving the thread take-up plate 2 to rotate, the swing arm 8.1 abuts against the stop 8.3 under the action of the first elastic element, the swing arm 8.1 rotates synchronously with the thread take-up plate 2, and there is a gap between the pressure roller 8.2 and the sewing thread 4 passing through the adjustment hole 3.2; that is, when the rotation angle of the thread take-up plate 2 is less than the set angle, the swing arm pressure mechanism 8 does not work, and only by the rotation of the thread take-up plate 2 can the frictional resistance of the sewing thread 4 passing through the thread adjustment channel 3 be adjusted to adjust the thread tension.

[0050] When the thread take-up plate 2 rotates to the set angle, the swing arm 8.1 abuts against the limiting member, which restricts the rotation of the swing arm 8.1. Subsequently, as the rotation angle of the thread take-up plate 2 increases, the pressure roller 8.2 on the swing arm 8.1 will gradually approach the thread 4 until the pressure roller 8.2 presses the thread 4 against the inner wall of the adjusting hole 3.2. At this time, the thread take-up plate 2 is restricted from rotating. During this process, the pressure roller 8.2 presses the thread 4 against the inner wall of the adjusting hole 3.2 to quickly increase the pressing force of the thread 4, thereby quickly increasing the thread tension.

[0051] This invention employs a rotating thread take-up plate 2 to adjust the frictional resistance of the thread 4 passing through the thread guide 3, thereby regulating thread tension. However, as the rotation angle of the thread take-up plate 2 increases, the curvature of the thread 4 passing through the thread guide 3 intensifies (the thread 4 forms a V-shape), increasing frictional resistance. Consequently, during sewing, the thread 4 is prone to breakage at the edge of the thread hole 3.1 or the edge of the adjustment hole 3.2. To address this issue, this solution incorporates a swing arm thread pressing mechanism 8, which can achieve a larger amount of thread tension adjustment while effectively controlling and reducing the rotation angle of the thread take-up plate 2. Specifically… During the process of the thread take-up plate drive mechanism 6 driving the thread take-up plate 2 to rotate from the initial state, when the rotation angle of the thread take-up plate 2 is less than the set angle, the swing arm 8.1 abuts against the stop 8.3 under the action of the first elastic element. The swing arm 8.1 rotates synchronously with the thread take-up plate 2, and there is a gap between the pressure roller 8.2 and the sewing thread 4 passing through the adjustment hole 3.2. That is, when the rotation angle of the thread take-up plate 2 is less than the set angle, the swing arm pressure mechanism 8 does not work. Only by rotating the thread take-up plate 2 can the frictional resistance of the sewing thread 4 passing through the thread adjustment channel 3 be adjusted to adjust the thread tension.

[0052] When the thread take-up plate 2 rotates to the set angle, the swing arm 8.1 rests against the limiting member, which restricts the rotation of the swing arm 8.1. Subsequently, as the rotation angle of the thread take-up plate 2 increases, the pressure roller 8.2 on the swing arm 8.1 gradually approaches the thread 4 until the pressure roller 8.2 presses the thread 4 tightly against the inner wall of the adjusting hole 3.2. At this point, the thread take-up plate 2 is restricted from rotating. During this process, the pressure roller 8.2 presses the thread 4 tightly against the inner wall of the adjusting hole 3.2, rapidly increasing the tension of the thread 4 and thus rapidly increasing the thread tension. Therefore, when the rotation angle of the thread take-up plate 2 reaches the set angle and the rotation angle is increased, the adjustment amount of the thread tension can be rapidly increased. This achieves a larger adjustment amount of thread tension while effectively controlling the reduction of the rotation angle of the thread take-up plate 2, thereby effectively preventing the rotation angle of the thread take-up plate 2 from being too large, which could cause the thread 4 to bend too drastically after passing through the thread guide 3, resulting in the thread 4 breaking at the edge of the thread hole 3.1 or the edge of the adjusting hole 3.2.

[0053] In this specific embodiment four, the remaining structure is the same as in specific embodiment three, except that... like Figure 4 As shown, in this embodiment, the limiting element is an elastic element 8.5. The elastic element 8.5 is connected between the bracket 1 and the swing arm 8.1. The elastic element 8.5 and the stop 8.3 are located on opposite sides of the swing arm 8.1. The elastic element 8.5 is a tension spring or a rubber band. The elastic element 8.5 provides elastic force to cause the swing arm 8.1 to drive the pressure roller 8.2 close to the seam 4 passing through the adjustment hole 3.2.

[0054] When the thread-picking plate 2 is in the initial state, the first elastic element overcomes the force of the elastic element, causing the swing arm 8.1 to press against the stop 8.3 under the action of the first elastic element.

[0055] When the thread take-up plate 2 rotates to the set angle, the elastic element will overcome the force of the first elastic element and restrict the rotation of the swing arm 8.1; causing the pressure roller 8.2 on the swing arm 8.1 to gradually approach the thread 4 and press the thread 4 between the pressure roller 8.2 and the inner wall of the adjusting hole 3.2. After the pressure roller 8.2 presses the thread 4 against the inner wall of the adjusting hole 3.2, the drive motor 6.1 can continue to drive the thread take-up plate 2 to rotate at a certain angle, thereby gradually increasing the pressing force of the pressure roller 8.2 on the thread 4.

[0056] The specific operation of the swing arm pressing mechanism 8 in this embodiment is as follows: Similar to Embodiment 3, when the rotation angle of the thread take-up plate 2 is less than the set angle, during the process of the thread take-up plate drive mechanism 6 driving the thread take-up plate 2 to rotate, the swing arm 8.1 abuts against the stop 8.3 under the action of the first elastic element. The swing arm 8.1 rotates synchronously with the thread take-up plate 2, and there is a gap between the pressure roller 8.2 and the sewing thread 4 passing through the adjustment hole 3.2. That is, when the rotation angle of the thread take-up plate 2 is less than the set angle, the swing arm pressure mechanism 8 does not work. Only by rotating the thread take-up plate 2 can the frictional resistance of the sewing thread 4 passing through the thread adjustment channel 3 be adjusted to adjust the thread tension.

[0057] When the thread take-up plate 2 rotates to the set angle, the elastic element will overcome the force of the first elastic element and restrict the rotation of the swing arm 8.1. Subsequently, as the rotation angle of the thread take-up plate 2 increases, the pressure roller 8.2 on the swing arm 8.1 will gradually approach the thread 4 and press the thread 4 between the pressure roller 8.2 and the inner wall of the adjustment hole 3.2. After the pressure roller 8.2 presses the thread 4 against the inner wall of the adjustment hole 3.2, the drive motor 6.1 can continue to drive the thread take-up plate 2 to rotate at a certain angle, gradually increasing the pressure force exerted by the pressure roller 8.2 on the thread 4. This effectively controls and reduces the rotation angle of the thread take-up plate 2 while achieving a larger amount of thread tension adjustment, thus effectively preventing the thread take-up plate 2 from rotating too much, causing the thread 4 to bend too drastically after passing through the thread guide 3, resulting in the thread 4 breaking at the edge of the thread hole 3.1 or the edge of the adjustment hole 3.2.

[0058] Furthermore, the swing arm thread pressing mechanism 8 in this embodiment also includes a front limit member and a rear limit member, which are fixed to the bracket 1 or the frame of the sewing machine. The thread take-up plate 2 is located between the front limit member and the rear limit member to limit the rotation angle of the thread take-up plate 2. When the thread take-up plate 2 abuts against the front limit member, the thread take-up plate 2 is in its initial state.

[0059] Specific embodiment five: A sewing method using a thread adjusting device of a sewing machine, including the following steps. Divide the stitches into several sewing sections and set the thread tension of the thread 4 corresponding to each sewing section. For example, divide the stitches into four sewing sections A, B, C, and D, and set the thread tension of the thread 4 corresponding to each of the four sewing sections A, B, C, and D according to actual needs.

[0060] During the sewing process, the thread take-up plate of the thread adjusting device is driven by a set angle to rotate the thread take-up plate, adjusting the thread tension of each sewing section to the set value. In this way, the thread tension can be adjusted as needed during sewing to adapt to different application and work scenarios, thereby improving the quality of the sewing stitches.

[0061] In this embodiment, the sewing machine's control system has a human-machine interface (HMI) with several input interfaces for thread tension parameters. The HMI contains default thread tension parameters or previously stored parameters. Once the system enters the HMI, the user can set the various thread tension parameters as needed. The sewing machine's control system uses an internal algorithm to convert changes in the corresponding thread tension parameters into changes in the rotation angle of the drive motor, thereby controlling the rotation angle of the take-up plate to adjust the thread tension as required by the thread guide.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, alterations, and equivalent transformations made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A thread adjusting device for a sewing machine, characterized in that, include: support; The cable tray is rotatably mounted on the bracket via a support shaft; The cable guide includes two threading holes on the bracket and an adjustment hole on the cable take-up plate, with the cable take-up plate located between the two threading holes; The thread-picking board drive mechanism includes a drive motor that drives the thread-picking board to rotate; The sewing machine thread passes through one thread hole, an adjustment hole, and another thread hole in sequence; the take-up plate drive mechanism drives the take-up plate to rotate, so as to adjust the frictional resistance of the sewing thread as it passes through the thread adjustment path during the operation of the sewing machine.

2. The thread adjusting device for a sewing machine according to claim 1, characterized in that, It also includes a swing arm wire pressing mechanism, which comprises: The swing arm has one end rotatably mounted on a support shaft; The pressure roller is rotatably located at the other end of the swing arm, and the pressure roller is located inside the adjustment hole; A stopper is provided on the line take-up plate; The first elastic element, the swing arm abuts against the stop under the action of the first elastic element, at this time there is a gap between the pressure roller and the sewing thread passing through the adjustment hole; The limiting component is located on the bracket or between the bracket and the swing arm; During the process of the thread take-up plate drive mechanism driving the thread take-up plate to rotate in order to increase the frictional resistance of the sewing thread passing through the thread adjustment channel, when the rotation angle of the thread take-up plate reaches the set angle, the limiting component will restrict the rotation of the swing arm, so that the pressure roller gradually approaches the sewing thread and presses the sewing thread between the pressure roller and the inner wall of the adjustment hole.

3. The thread adjusting device for a sewing machine according to claim 2, characterized in that, The limiting component is fixedly mounted on the bracket, and the limiting component is located on the same side of the stop component as the swing arm.

4. The thread adjusting device for a sewing machine according to claim 2, characterized in that, The limiting element is an elastic element connected between the bracket and the swing arm. The elastic element is a tension spring or a rubber band. The elastic element provides elastic force to make the swing arm drive the pressure roller to approach the seam passing through the adjustment hole.

5. A thread adjusting device for a sewing machine according to claim 1, 2, 3, or 4, characterized in that, The thread-picking plate driving mechanism also includes: A sliding member is slidably mounted on the bracket. The sliding member is provided with a drive pin. The wire take-up plate has a strip-shaped hole extending radially along the support shaft, and the drive pin extends into the strip-shaped hole. The rack and gear mesh with each other, with the rack fixed on a sliding component, and the drive motor drives the gear to rotate.

6. The thread adjusting device for a sewing machine according to claim 5, characterized in that, The take-up plate is provided with a strip plate extending radially along the support shaft, the strip hole is provided on the strip plate, the gear is located below the rack, and the drive motor is located below the support shaft.

7. A thread adjusting device for a sewing machine according to claim 1, 2, 3, or 4, characterized in that, The adjustment hole is arc-shaped and extends circumferentially around the support shaft.

8. A thread adjusting device for a sewing machine according to claim 1, 2, 3, or 4, characterized in that, It also includes a thread clamp, which consists of two pressure plates and a threaded adjustment knob. The adjustment knob adjusts the clamping force between the two pressure plates. The sewing thread first passes between the two pressure plates and then passes through the thread guide.

9. A thread adjusting device for a sewing machine according to claim 1, 2, 3, or 4, characterized in that, The bracket includes a mounting base and a wire guide plate. The wire guide plate is located between the mounting base and the wire guide plate. One of the two wire holes is located on the mounting base, and the other wire hole is located on the wire guide plate. The support shaft is located on the mounting base.

10. A sewing method, employing the thread adjusting device of a sewing machine according to any one of claims 1-9, characterized in that, Includes the following steps, Divide the sewing stitches into several sewing sections and set the thread tension for each sewing section. During the sewing process, the thread take-up plate of the thread adjustment device is driven to rotate at a set angle by the thread take-up plate drive mechanism, so as to adjust the thread tension of each sewing section to the set value.

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