A multi-section motor thread trimming control method for a sewing machine

Abstract

The application discloses a sewing machine multi-section motor thread trimming control method and belongs to the technical field of sewing equipment. The method solves the problems of unstable thread trimming and different lengths of thread stubs. The control method comprises the following steps: S1, after starting thread trimming, waiting for the main shaft to rotate to reach the cutting angle alpha, starting the work of the thread trimming stepping motor and starting thread separation at the thread separation rotating speed V1 until completing thread separation; S2, after completing thread separation, reducing the rotating speed of the thread trimming stepping motor from the thread separation rotating speed V1 to the thread protection rotating speed V2, starting the moving knife of the thread trimming mechanism to clamp the bobbin thread and the top thread on the thread groove and completing thread protection; S3, when the main shaft continues to rotate to reach the angle beta, switching the rotating speed of the thread trimming stepping motor to the thread breaking rotating speed V3 and starting the moving knife to approach the fixed knife and engage with the fixed knife to realize thread trimming and complete thread trimming. The method has the advantage of good thread trimming stability.

Description

Technical Field

[0001] This invention relates to the field of sewing equipment technology, and in particular to a method for controlling the thread cutting of a multi-segment motor in a sewing machine. Background Technology

[0002] Sewing machines and template machines are both sewing equipment commonly used in the textile industry, primarily for processing clothing, footwear, and other products. Sewing machines connect and secure materials by stitching thread onto the fabric; template machines, on the other hand, sew materials using the shape and position of a template. Existing sewing machines and template machines typically employ simple single-motor, single-stage control or mechanical thread-cutting mechanisms. While this control method is simple, it cannot achieve stable thread cutting or precise control of the thread end, easily leading to problems such as incomplete thread cutting or inconsistent thread lengths.

[0003] To address the aforementioned issues, a Chinese patent, CN115897086A, entitled "A Sewing Machine Thread Trimming Control Method," has been published. This method includes the following steps: S1. An electronic control module, a main shaft, an encoder for detecting the main shaft angle, and a thread trimming mechanism are installed in the sewing machine. The encoder is communicatively connected to the electronic control module, and the main shaft angle has an encoder edge zero position uniquely determined by the encoder output signal. The thread trimming mechanism includes a thread trimming motor (10), a thread trimming transmission mechanism, a moving blade (20), and a fixed blade (30). The thread trimming motor (10) is connected to the moving blade (20) via the thread trimming transmission mechanism, driving the moving blade (20) to reciprocate towards or away from the fixed blade (30). The thread trimming transmission mechanism includes an avoidance unit, and the thread trimming motor (10) is communicatively connected to the electronic control module. S2. Determining the needle stop angle and the thread splitting start angle of the main shaft: the main shaft's... The needle stop angle = encoder edge zero position + first preset angle, the spindle splitting start angle = encoder edge zero position + second preset angle, the first preset angle and the second preset angle are both pre-stored in the electronic control module; S3, when sewing ends, the electronic control module receives the thread cutting signal and performs the following control: the spindle rotates for the last revolution, when the spindle rotates from the needle stop angle of the last revolution through a third preset angle, the electronic control module controls the motor shaft of the thread cutting motor (10) to rotate along the first direction, the avoidance unit of the thread cutting mechanism makes no power transmission between the thread cutting transmission mechanism and the moving knife (20), and at the same time the sewing machine performs the thread loosening action; the spindle continues to rotate for the last revolution, when the spindle rotates to the splitting start angle, the avoidance unit of the thread cutting mechanism makes power transmission between the thread cutting transmission mechanism and the moving knife (20), as the motor shaft of the thread cutting motor (10) continues to rotate along the first direction, the thread cutting mechanism performs the splitting action and the thread cutting action in sequence.

[0004] The above solution effectively addresses the problem of instability in wire cutting. However, designing different control methods to solve the problems of unstable wire cutting and inconsistent wire lengths is a direction that those skilled in the art should strive for. Summary of the Invention

[0005] This application provides a multi-segment motor thread cutting control method for sewing machines, which solves the technical problems of unstable thread cutting and inconsistent thread length in the prior art, and achieves the beneficial effects of good thread cutting stability and precise control of thread length.

[0006] This application provides a method for controlling the thread cutting of a multi-segment motor in a sewing machine, characterized by the following steps:

[0007] S1, Line Control Phase

[0008] After starting the thread cutting, wait for the spindle to rotate to the cutting angle α. Then, the thread cutting stepper motor starts working and begins to move the bottom and top threads towards the fixed blade at the thread cutting speed V1 to separate the threads until the separation is completed.

[0009] Wherein, the cutting angle α is the deflection angle of the main shaft when the moving blade of the wire cutting mechanism starts to move the bottom line and the top line towards the fixed blade to separate the lines;

[0010] S2, Line Protection Control Stage

[0011] After the wire separation is completed, the speed of the wire cutting stepper motor is reduced from the wire separation speed V1 to the wire protection speed V2. The moving blade of the wire cutting mechanism begins to move the bottom and top wires closer to the fixed blade after the above-mentioned wire separation until the bottom and top wires are stuck into the wire groove, thus completing the wire protection.

[0012] S3, Thread Trimming Control Stage

[0013] When the spindle continues to rotate to angle β, the speed of the wire cutting stepper motor switches to the wire breaking speed V3 and begins to drive the moving blade to approach the fixed blade and engage with the fixed blade to cut the wire, thus completing the wire cutting.

[0014] Wherein, angle β is the deflection angle of the main shaft when the moving blade of the wire cutting mechanism begins to move towards the fixed blade direction with the bottom and top lines after the wire is protected;

[0015] S4. When the spindle continues to rotate to angle γ, the spindle motor stops running, and the wire cutting stepper motor resets, thus completing the multi-segment motor wire cutting operation.

[0016] Among them, angle γ is the starting and stopping angle of the main spindle motor.

[0017] In the above-mentioned multi-segment motor thread cutting control method for a sewing machine, the method is characterized in that: in step S2, when the thread separation is completed, before the moving blade starts to move the bottom thread and top thread towards the fixed blade after the separation, the thread loosening electromagnet is controlled to loosen the thread; in step S3, before the moving blade is driven to approach the fixed blade and engage with the fixed blade to cut the thread, the thread loosening electromagnet is controlled to close and clamp, while the thread sweeping electromagnet is activated to sweep the thread.

[0018] In the above-mentioned multi-segment motor thread cutting control method for a sewing machine, the thread splitting action in step S1 is completed when or before the rotary hook finishes winding the thread to the lowest position.

[0019] In the above-mentioned multi-segment motor thread cutting control method for a sewing machine, the characteristic is that: in step S3, when the main shaft rotates to angle β, the main shaft thread take-up lever reaches its highest position.

[0020] In the above-mentioned multi-segment motor thread cutting control method for a sewing machine, the thread cutting speed V1 is characterized by being 250 rpm to 350 rpm. Preferably, it is 300 rpm.

[0021] In the above-mentioned multi-segment motor thread-cutting control method for a sewing machine, the characteristic feature is that the thread-hooking speed V2 is 80 rpm to 150 rpm. Preferably, it is 100 rpm.

[0022] In the above-mentioned multi-segment motor thread-cutting control method for a sewing machine, the thread-cutting speed V3 is characterized by being 40 rpm to 60 rpm, and the thread-cutting stepper motor resetting during reset operates at a reset speed of 150 rpm to 250 rpm. Preferably, the thread-cutting speed V3 is 50 rpm, and the reset speed is 200 rpm.

[0023] In the above-described method for controlling the thread cutting of a multi-segment motor in a sewing machine, the cutting angle α is characterized by being 290° to 310°. Preferably, it is 304°.

[0024] In the above-described method for controlling the thread cutting of a multi-segment motor in a sewing machine, the characteristic feature is that the angle β is 65° to 75°. Preferably, it is 70°.

[0025] In the above-described method for controlling the thread cutting of a multi-segment motor in a sewing machine, the characteristic feature is that the angle γ is 48° to 58°. Preferably, it is 53°.

[0026] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0027] By employing a multi-segment motor control method, specifically by adjusting the timing of the wire-cutting stepper motor in segments according to the different angle positions of the spindle, the stepper motor controls the moving blade to precisely control the wire separation, wire protection, and wire cutting operations according to the mechanical running trajectory. Therefore, this effectively solves the technical problem of poor wire cutting stability in existing technologies, which leads to the inability to cut the wire. As a result, it achieves the beneficial effects of good wire cutting stability and precise control over the length of the cut wire ends. Attached Figure Description

[0028] Figure 1 This is a flowchart of the multi-segment motor thread-cutting control method for this sewing machine.

[0029] Figure 2 This is a flowchart illustrating the working principle of the multi-segment motor thread-cutting control method for this sewing machine. Detailed Implementation

[0030] This application provides a multi-segment motor thread cutting control method for sewing machines, which solves the technical problems of unstable thread cutting and inconsistent thread lengths in the prior art.

[0031] The technical solution in this application embodiment aims to solve the problems of unstable wire cutting and inconsistent wire end lengths. The overall approach is as follows:

[0032] like Figure 1 As shown, this can be achieved through the following steps:

[0033] S1, Line Control Phase

[0034] After starting the thread cutting, wait for the spindle to rotate to the cutting angle α. Then, the thread cutting stepper motor starts working and begins to move the bottom and top threads towards the fixed blade at the thread cutting speed V1 to separate the threads until the separation is completed.

[0035] Wherein, the cutting angle α is the deflection angle of the main shaft when the moving blade of the wire cutting mechanism starts to move the bottom line and the top line towards the fixed blade to separate the lines;

[0036] S2, Line Protection Control Stage

[0037] After the wire separation is completed, the speed of the wire cutting stepper motor is reduced from the wire separation speed V1 to the wire protection speed V2. The moving blade of the wire cutting mechanism begins to move the bottom and top wires closer to the fixed blade after the above-mentioned wire separation until the bottom and top wires are stuck into the wire groove, thus completing the wire protection.

[0038] S3, Thread Trimming Control Stage

[0039] When the spindle continues to rotate to angle β, the speed of the wire cutting stepper motor switches to the wire breaking speed V3 and begins to drive the moving blade to approach the fixed blade and engage with the fixed blade to cut the wire, thus completing the wire cutting.

[0040] Wherein, angle β is the deflection angle of the main shaft when the moving blade of the wire cutting mechanism begins to move towards the fixed blade direction with the bottom and top lines after the wire is protected;

[0041] S4. When the spindle continues to rotate to angle γ, the spindle motor stops running, and the wire cutting stepper motor resets, thus completing the multi-segment motor wire cutting operation.

[0042] Among them, angle γ is the starting and stopping angle of the main spindle motor.

[0043] By adjusting the timing of the wire-cutting stepper motor in segments according to the different angle positions of the spindle, the stepper motor controls the moving blade to precisely control the wire separating, protecting, and cutting operations according to the mechanical running trajectory. This multi-segment motor control method effectively solves the technical problem of poor wire cutting stability in existing technologies, which leads to the inability to cut the wire.

[0044] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0045] Example 1

[0046] A method for controlling the thread cutting of a multi-segment motor in a sewing machine is provided, comprising the following steps:

[0047] S1, Line Control Phase

[0048] After starting the thread cutting, wait for the main shaft to rotate to the cutting angle α. The thread cutting stepper motor starts working and starts to move the bottom thread and top thread towards the fixed blade at the thread splitting speed V1 to split the thread until the splitting is completed. The splitting action is completed when or before the rotary hook finishes winding the thread to the lowest position, so as to ensure that the thread splitting action is completed under tension.

[0049] Wherein, the cutting angle α is the deflection angle of the main shaft when the moving blade of the wire cutting mechanism begins to move the bottom and top lines towards the fixed blade to separate the lines. The cutting angle α is 290°~310°, and in this embodiment, the cutting angle α is 304°. The cutting angle α is a preset angle, derived from the mechanical structure, and is the angle at the moment when the bottom and top lines separate. The preset line separating speed V1 is 250 rpm~350 rpm, and in this embodiment, the line separating speed V1 is specifically 300 rpm. Whether the line separating is complete can be determined by the position of the wire cutting stepper motor, or by the number of steps, preset, or by the stroke, etc.

[0050] S2, Line Protection Control Stage

[0051] After the wire separation is completed, the speed of the wire cutting stepper motor is reduced from the wire separation speed V1 to the wire protection speed V2. At the same time, the wire loosening electromagnet is controlled to loosen the wire. The moving blade of the wire cutting mechanism begins to move the bottom and top wires closer to the fixed blade after the above-mentioned wire separation until the bottom and top wires are stuck into the wire groove, thus completing the wire protection.

[0052] The hooking speed V2 is 80 rpm to 150 rpm, and in this embodiment, the hooking speed V2 is 100 rpm.

[0053] S3, Thread Trimming Control Stage

[0054] When the spindle continues to rotate to angle β, the control solenoid for loosening the wire closes and clamps the wire, while the sweeping solenoid opens to sweep the wire. At this time, the spindle take-up lever reaches the highest position, the speed of the wire cutting stepper motor switches to the wire breaking speed V3 and starts to drive the moving blade to approach the fixed blade and engage with the fixed blade to cut the wire, thus completing the wire cutting.

[0055] Wherein, angle β is the deflection angle of the main shaft when the moving blade of the wire cutting mechanism continues to approach the fixed blade direction with the bottom and top lines after the wire is protected; angle β is 65° to 75°, and in this embodiment, angle β is 70°.

[0056] S4. When the spindle continues to rotate to angle γ, the spindle motor stops running, and the wire cutting stepper motor resets, thus completing the multi-segment motor wire cutting operation.

[0057] Among them, angle γ is the running and stopping angle of the main spindle motor, and angle γ is 48° to 58°. In this embodiment, angle γ is 53°.

[0058] like Figure 2 As shown, the specific control process of this multi-segment motor thread-cutting control method for sewing machines is as follows:

[0059] After the wire cutting begins, the spindle's cutting angle α is checked to see if it reaches 304°. If it does, the wire cutting stepper motor starts working, and the wire separating control stage begins. The first segment of the wire cutting stepper motor starts separating the wire, with a separating speed V1 of 300 rpm. Then, the stepper motor waits for the wire cutting stepper motor to complete its stroke (i.e., the wire separating action is complete). After the wire separating action is completed, the wire guarding control stage begins. At this time, the wire hooking speed V2 is 100 rpm, meaning the second segment of the wire cutting stepper motor starts guarding the wire. Simultaneously, the wire loosening solenoid is controlled to loosen the wire. When the spindle rotates to the angle β = 70°, the wire cutting stepper motor speed switches to the wire breaking speed V3, initiating the wire breaking control stage. The third segment of the wire cutting stepper motor starts breaking the wire. At this time, the wire loosening solenoid is controlled to close and clamp, while the wire sweeping solenoid is activated to sweep the wire. When the spindle rotates to the angle γ = 53°, it stops, the spindle motor stops running, and the wire cutting stepper motor resets, completing the wire cutting.

[0060] Employing multi-segment motor control technology, the system controls the wires in segments based on the spindle's angle position, ensuring the shears accurately separate the bottom and top threads. Specifically, in the first step, when the spindle deflection angle reaches 304°, the wire-cutting stepper motor operates at a high speed of 300 rpm to quickly initiate the wire-cutting control. During this stage, the motor speed is kept as fast and stable as possible to ensure the moving blades can separate the bottom and top threads, completing the wire-cutting action when the rotary hook reaches its lowest position. In the second step, the wire-cutting stepper motor switches to a slower speed of 100 rpm, moving to the second segment and stopping at the pre-cutting position. At this point, the moving blades have already engaged the thread in the thread groove. The slower speed aids in thread-hooking control and improves cutting stability. Third, the spindle continues to run until angle β = 70°. At this point, the spindle take-up lever reaches its highest position (ensuring the longest possible thread length). Then, the thread-cutting stepper motor is switched to the thread-breaking speed V3 and begins to drive the moving blade to approach and engage with the stationary blade to cut the thread. The thread cutting is then completed. At this point, the thread-releasing electromagnet is deactivated, the thread-sweeping control is activated, the spindle returns to its 53° position, and the thread-cutting stepper motor resets, completing stable thread-cutting control. Real-time monitoring and adjustment are employed to monitor and adjust the thread-cutting, splitting, winding, and take-up processes, further improving cutting accuracy and effectiveness.

[0061] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages:

[0062] 1. Precise Control: This invention employs a multi-segment motor control method. The cutting stepper motor is programmed to control the shearing action, and coordinated with a wire-releasing electromagnet and a wire-sweeping electromagnet. The operation is segmented according to the spindle's angle position, controlling the cutting stepper motor to operate at the optimal speed in each segment, achieving precise control of the cutting stepper motor's operation. Compared to the single-motor control method in existing technologies, this invention offers more refined control, effectively avoiding inaccurate cutting caused by unstable or improperly controlled cutting stepper motor speeds, thus improving the cutting rate and the stability of the cut wire length.

[0063] 2. Real-time monitoring and adjustment: This invention controls the wire-cutting stepper motor to operate in segments according to the angular position of the spindle, enabling real-time monitoring and adjustment of the wire-cutting process. Compared to existing technologies, this invention offers more flexible control, allowing for real-time adjustments based on actual conditions during the wire-cutting process, further improving cutting accuracy and effectiveness.

[0064] 3. Improve production efficiency: This segmented control operation mode can effectively improve the stability of wire cutting, thereby increasing production efficiency, shortening the production cycle, and reducing production costs;

[0065] 4. Good stability: Compared with the existing technology, the control method of the present invention is more stable and improves the quality of wire cutting.

[0066] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0067] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for controlling the thread cutting of a multi-segment motor in a sewing machine, characterized in that, Includes the following steps: S1, Line Control Phase After starting the thread cutting, wait for the spindle to rotate to the cutting angle α. Then, the thread cutting stepper motor starts working and begins to move the bottom and top threads towards the fixed blade at the thread cutting speed V1 to separate the threads until the separation is completed. Wherein, the cutting angle α is the deflection angle of the main shaft when the moving blade of the wire cutting mechanism starts to move the bottom line and the top line towards the fixed blade to separate the lines; S2, Line Protection Control Stage After the wire separation is completed, the speed of the wire cutting stepper motor is reduced from the wire separation speed V1 to the wire protection speed V2. The moving blade of the wire cutting mechanism begins to move the bottom and top wires closer to the fixed blade after the above-mentioned wire separation until the bottom and top wires are stuck into the wire groove, thus completing the wire protection. S3, Thread Trimming Control Stage When the spindle continues to rotate to angle β, the speed of the wire cutting stepper motor switches to the wire breaking speed V3 and begins to drive the moving blade to approach the fixed blade and engage with the fixed blade to cut the wire, thus completing the wire cutting. Wherein, angle β is the deflection angle of the main shaft when the moving blade of the wire cutting mechanism begins to move towards the fixed blade direction with the bottom and top lines after the wire is protected; S4. When the spindle continues to rotate to angle γ, the spindle motor stops running, and the wire cutting stepper motor resets, thus completing the multi-segment motor wire cutting operation. Among them, angle γ is the running and stopping angle of the main spindle motor.

2. The method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 1, characterized in that, In step S2, when the line separation is completed, before the moving blade starts to move the bottom and top lines closer to the fixed blade after the line separation, the wire release electromagnet is controlled to release the lines. In step S3, before the moving blade moves closer to the fixed blade and engages with the fixed blade to cut the lines, the wire release electromagnet is controlled to close and clamp the lines, while the wire sweeping electromagnet is activated to sweep the lines.

3. The method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 2, characterized in that, The splitting action in step S1 is completed when or before the rotary hook finishes winding to the lowest position.

4. The method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 3, characterized in that, In step S2, when the spindle rotates to angle β, the spindle take-up lever reaches its highest position.

5. A method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 1, 2, 3, or 4, characterized in that, The speed of the dividing line V1 is 250 rpm to 350 rpm.

6. The method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 5, characterized in that, The guard rotation speed V2 is 80 rpm to 150 rpm.

7. The method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 6, characterized in that, The wire-breaking speed V3 is 40 rpm to 60 rpm, and the wire-cutting stepper motor resets at a reset speed of 150 rpm to 250 rpm.

8. A method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 1, 2, 3, or 4, characterized in that, The cutting angle α is 290° to 310°.

9. A method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 8, characterized in that, The angle β is 65° to 75°.

10. A method for controlling the thread cutting of a multi-segment motor in a sewing machine as described in claim 9, characterized in that, The angle γ is 48° to 58°.

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