A method, system, device and storage medium for controlling the speed of a sewing machine

Abstract

The present application discloses a method for controlling the speed of a sewing machine, which is applied to the field of sewing technology, comprising: when the rotary hook of the sewing machine is at the thread hooking point, controlling the speed of the sewing machine main shaft to a minimum first speed; when the rotary hook moves from the thread hooking point to the position of the maximum thread demand point, controlling the speed of the sewing machine main shaft according to a preset rule; when the rotary hook is at the position of the maximum thread demand point, increasing the speed of the sewing machine main shaft until the thread take-up lever of the sewing machine reaches the highest point, controlling the speed of the sewing machine main shaft to reach a maximum second speed; when the position of the thread take-up lever begins to drop from the highest point, reducing the speed of the sewing machine main shaft until the first speed is reached when the rotary hook is at the thread hooking point. The application of the solution of the present application ensures the average speed of the sewing machine main shaft and reduces the probability of thread throw and thread breakage. The present application also provides a speed control system, device and storage medium for a sewing machine, which have corresponding effects.

Description

Technical Field

[0001] The present invention relates to the field of sewing technology, and in particular to a speed control method, system, device and storage medium for a sewing machine. Background Art

[0002] Sewing machines can sometimes experience thread drop and thread breakage during sewing. This is especially true for large-hook template machines, which typically operate at relatively low speeds, typically between 2200 and 2500 RPM (Revolutions Per Minute). When speeds exceed 2800 RPM, the likelihood of thread drop and thread breakage increases, resulting in suboptimal sewing performance.

[0003] In summary, how to effectively improve sewing performance and reduce the probability of thread throw and thread breakage is a technical problem that those skilled in the art urgently need to solve. Summary of the Invention

[0004] The object of the present invention is to provide a sewing machine speed control method, system, device and storage medium to effectively improve sewing performance and reduce the probability of thread drop and thread breakage.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A method for controlling the rotational speed of a sewing machine, comprising:

[0007] When the rotary hook of the sewing machine is at the thread hooking point, the speed of the main shaft of the sewing machine is controlled to be a preset first speed;

[0008] During the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, the speed of the sewing machine main shaft is controlled according to a preset rule;

[0009] When the rotary hook is at the position of the maximum thread demand point, the speed of the sewing machine main shaft is increased until the thread take-up lever of the sewing machine reaches the highest point, and the speed of the sewing machine main shaft is controlled to reach a preset second speed;

[0010] When the thread take-up lever begins to descend from its highest point, the speed of the sewing machine main shaft is reduced until the rotary hook is at the thread hooking point, and the speed of the sewing machine main shaft is controlled to reach the first speed;

[0011] The first rotational speed is the minimum rotational speed during one rotation of the sewing machine main shaft, and the second rotational speed is the maximum rotational speed during one rotation of the sewing machine main shaft.

[0012] Preferably, in the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, the speed of the sewing machine main shaft is controlled according to a preset rule, including:

[0013] During the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, controlling the rotation speed of the sewing machine main shaft to increase from the first rotation speed to a preset third rotation speed;

[0014] Among them, the third speed is greater than the first speed, and the third speed is less than the second speed, and the third speed satisfies: V3<(V1+V2) / 2, V1, V2 and V3 respectively represent the value of the first speed, the value of the second speed and the value of the third speed.

[0015] Preferably, controlling the speed of the sewing machine main shaft to increase from the first speed to a preset third speed includes:

[0016] According to a fixed first acceleration or a variable acceleration control method, the rotational speed of the sewing machine main shaft is controlled to increase from the first rotational speed to a preset third rotational speed.

[0017] Preferably, when the rotary hook is at the position of the maximum thread demand point, the speed of the sewing machine main shaft is increased until the thread take-up lever of the sewing machine reaches the highest point, and the speed of the sewing machine main shaft is controlled to reach a preset second speed, including:

[0018] In the process from when the rotary hook is at the maximum thread demand point to when the thread take-up lever of the sewing machine reaches the highest point, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to the fixed second acceleration.

[0019] Preferably, when the rotary hook is at the position of the maximum thread demand point, the speed of the sewing machine main shaft is increased until the thread take-up lever of the sewing machine reaches the highest point, and the speed of the sewing machine main shaft is controlled to reach a preset second speed, including:

[0020] In the process from when the rotary hook is at the maximum thread demand point to when the thread take-up rod of the sewing machine reaches the highest point, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is reduced in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is gradually reduced.

[0021] Preferably, when the position of the thread take-up lever begins to descend from the highest point, the speed of the sewing machine main shaft is reduced until the rotary hook is at the thread hooking point, and the speed of the sewing machine main shaft is controlled to reach the first speed, comprising:

[0022] During the process of the thread take-up lever descending from the highest point until the rotary hook is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the fixed third acceleration.

[0023] Preferably, when the position of the thread take-up lever begins to descend from the highest point, the speed of the sewing machine main shaft is reduced until the rotary hook is at the thread hooking point, and the speed of the sewing machine main shaft is controlled to reach the first speed, comprising:

[0024] In the process of the thread take-up lever descending from the highest point until the rotary hook is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first increased in stages and then decreased in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first gradually increased and then gradually decreased.

[0025] A speed control system for a sewing machine, comprising:

[0026] A low-speed control module is used to control the speed of the sewing machine main shaft to a preset first speed when the rotary hook of the sewing machine is at the thread hooking point;

[0027] a speed increasing module, configured to control the speed of the sewing machine main shaft according to a preset rule when the rotary hook moves from the position of the thread hooking point to the position of the maximum thread demand point, and to increase the speed of the sewing machine main shaft when the rotary hook is at the position of the maximum thread demand point until the speed of the sewing machine main shaft reaches a preset second speed when the thread take-up lever of the sewing machine reaches the highest point;

[0028] a speed reducing module, configured to reduce the speed of the sewing machine main shaft when the thread take-up lever begins to descend from its highest point, until the speed of the sewing machine main shaft reaches the first speed when the rotary hook is at the thread hooking point;

[0029] The first rotational speed is the minimum rotational speed during one rotation of the sewing machine main shaft, and the second rotational speed is the maximum rotational speed during one rotation of the sewing machine main shaft.

[0030] A speed control device for a sewing machine, comprising:

[0031] memory for storing computer programs;

[0032] A processor is used to execute the computer program to implement the steps of the sewing machine speed control method as described in any one of the above.

[0033] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the speed control method for a sewing machine as described in any one of the above are implemented.

[0034] By applying the technical solution provided by the embodiment of the present invention, when the rotary hook of the sewing machine is at the thread hooking point, the speed of the sewing machine main shaft is controlled to a preset first speed. The first speed is the minimum speed during one rotation of the sewing machine main shaft. In other words, the main shaft speed is the lowest when the rotary hook is hooking the thread. In this way, the hook tip of the rotary hook is less likely to cut the suture thread, thereby reducing the probability of thread breakage. After the rotary hook is at the point where the thread is most needed, as the rotary hook moves, the suture thread will be separated from the lower shuttle bed and the guide wire sheet of the rotary hook due to the action of external forces, that is, the suture thread is in a suspended position. Therefore, the thread loop is easily disturbed and twisted or knotted, forming a throw point. In this regard, in the solution of the present application, when the rotary hook is at the point where the thread is most needed, the speed of the sewing machine main shaft is increased, causing the thread take-up rod to accelerate and rise to rewind the thread, thereby reducing the thread supply, which is conducive to preventing the thread loop from getting tangled and knotted in the air, thereby reducing the probability of throw points. After the rotary hook reaches the maximum thread demand point, the spindle speed continuously increases until, when the thread take-up lever of the sewing machine reaches its highest point, the spindle speed reaches a preset second speed, thereby increasing the average spindle speed during one rotation of the sewing machine spindle. As the thread take-up lever descends from its highest point, the spindle speed can be reduced until, when the rotary hook reaches the thread hook point, the spindle speed is controlled to reach the first speed.

[0035] In summary, the solution of the present application reduces the probability of thread throw and thread breakage while ensuring a high average speed during one rotation of the sewing machine main shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0037] Figure 1 1 is a flow chart of an implementation method of a sewing machine speed control method of the present invention;

[0038] Figure 2a Schematic diagram of the change process of the main shaft speed of a sewing machine in a specific embodiment of the present invention;

[0039] Figure 2b Schematic diagram of the change process of the main shaft speed of a sewing machine in another specific embodiment of the present invention;

[0040] Figure 3 The figure is a schematic structural diagram of a sewing machine in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0041] The core of the present invention is to provide a speed control method for a sewing machine, which reduces the probability of thread throw and thread breakage while ensuring a high average speed during one rotation of the sewing machine main shaft.

[0042] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0043] Please refer to Figure 1 , Figure 1 The flowchart of the speed control method of a sewing machine in the present invention is as follows. The speed control method of the sewing machine may include the following steps:

[0044] Step S101: When the rotary hook of the sewing machine is at the thread hooking point, the rotation speed of the main shaft of the sewing machine is controlled to be a preset first rotation speed.

[0045] In order to improve the sewing stability of the rotary hook, the solution of the present application controls the speed of the sewing machine main shaft to be the slowest when the rotary hook of the sewing machine is at the thread hooking point, that is, the speed of the sewing machine main shaft is controlled to a preset first speed, which is the minimum speed during the process of the sewing machine main shaft rotating one circle. In this way, the hook tip of the rotary hook is not likely to cut the thread when hooking the thread.

[0046] When determining whether the rotary hook of a sewing machine is at the thread hooking point, or when determining whether the rotary hook is at the maximum thread demand point, or when the thread take-up lever reaches its highest point, as described later, the position can usually be determined by the phase of the main shaft. Of course, in other specific situations, other position determination methods can be set as needed, as long as accurate position determination is achieved, and the implementation of the present invention is not affected.

[0047] The specific value of the first speed can be set and adjusted according to actual needs. For example, in the specific implementation of Table 1, the first speed is set to 2500 RPM.

[0048] Table 1: Parameter table of sewing machine spindle variable speed

[0049]

[0050]

[0051] Step S102: When the rotary hook moves from the position at the thread hooking point to the position at the maximum thread demand point, the rotation speed of the sewing machine main shaft is controlled according to a preset rule.

[0052] When the thread is hooked, as the hook continues to rotate, it will reach the point where the maximum thread is needed. When controlling the speed of the sewing machine spindle according to a preset rule, the specific rule can be set according to actual needs, but it is understood that the first speed when the hook is at the thread hook point is the minimum speed during one rotation of the sewing machine spindle, and the hook will not decelerate during the process of moving from the position at the thread hook point to the position where the maximum thread is needed.

[0053] For example, in a specific scenario, to ensure sewing stability, the spindle speed of the sewing machine can be maintained at a first speed during the process of the rotary hook moving from the thread hook point to the point where the maximum thread is needed. That is, during the process of the rotary hook moving from the thread hook point to the point where the maximum thread is needed, the spindle speed of the sewing machine can be controlled to remain at the first speed.

[0054] In a specific embodiment of the present invention, step S102 may specifically include:

[0055] During the process of the rotary hook moving from the position at the thread hooking point to the position at the maximum thread demand point, the speed of the sewing machine main shaft is controlled to increase from the first speed to the preset third speed;

[0056] The third speed is greater than the first speed and less than the second speed. The third speed satisfies: V3<(V1+V2) / 2, V1, V2 and V3 represent the value of the first speed, the value of the second speed and the value of the third speed respectively.

[0057] This embodiment takes into account that, during the process of the rotary hook moving from the thread hooking point to the position of the maximum thread demand point, an excessively fast spindle speed can easily reduce sewing stability. However, the speed can be appropriately increased. This helps to increase the average speed of the sewing machine spindle during one rotation without compromising sewing stability. Furthermore, since the spindle speed of the sewing machine needs to be increased when the rotary hook is at the position of the maximum thread demand point, in this embodiment, increasing the spindle speed from the first speed to a preset third speed also helps to quickly increase the spindle speed after the rotary hook reaches the position of the maximum thread demand point.

[0058] The specific value of the third speed can be set and adjusted according to actual needs. As can be seen from the description above, it should be slightly higher than the first speed. Therefore, in this embodiment, V3 < (V1 + V2) / 2. This allows the shuttle to slowly accelerate as it moves from the thread hook position to the point of maximum thread demand. During this process, the thread take-up lever moves downward, supplying the shuttle with thread, and the thread follows the shuttle's rotation until the shuttle reaches the point of maximum thread demand. In the embodiment shown in Table 1, the third speed is set to 2700 RPM.

[0059] Furthermore, in the process of controlling the speed of the sewing machine main shaft to increase from the first speed to the preset third speed, uniform acceleration or variable acceleration can be selected, that is, the speed of the sewing machine main shaft can be controlled to increase from the first speed to the preset third speed according to a fixed first acceleration or a variable acceleration control mode. In a specific embodiment, considering that the process of the rotary hook moving from the position at the thread hooking point to the position of the maximum thread demand point is relatively short and is a slow acceleration, that is, the spindle speed does not increase much, the uniform acceleration scheme is selected for its ease of implementation. That is, in a specific embodiment of the present invention, controlling the speed of the sewing machine main shaft to increase from the first speed to the preset third speed can specifically include: controlling the speed of the sewing machine main shaft to increase from the first speed to the preset third speed according to a fixed first acceleration, so that the scheme is easy to implement. When a uniform acceleration scheme is adopted, program design is also more convenient.

[0060] Of course, in some cases, the speed of the sewing machine spindle can be controlled to increase from the first speed to a preset third speed according to a variable acceleration control method. The specific variable acceleration method can be set and adjusted according to actual needs. In actual applications, considering that when the rotary hook is at the maximum thread demand point, a more appropriate method is to quickly increase the speed of the sewing machine spindle, therefore, in the process of controlling the speed of the sewing machine spindle to increase from the first speed to the preset third speed, the variable acceleration control can be performed according to the rule of increasing the absolute value of the speed change rate of the sewing machine spindle in a stepwise manner, or according to the rule of gradually increasing the absolute value of the speed change rate of the sewing machine spindle. That is, in the process of controlling the speed of the sewing machine spindle to increase from the first speed to the preset third speed, the acceleration increases gradually or in steps.

[0061] Step S103: When the rotary hook is at the maximum thread demand point, the speed of the sewing machine main shaft is increased until the thread take-up lever of the sewing machine reaches the highest point, and the speed of the sewing machine main shaft is controlled to reach a preset second speed.

[0062] When the rotary hook is at the point where the thread needs to be pulled to the maximum, as the rotary hook continues to move, the suture thread will be separated from the shuttle bed and the guide wire sheet under the rotary hook due to external forces, that is, the suture thread will be in a suspended position, so the thread loop is easily disturbed and twisted or knotted, forming a loose thread. In response to this, in the solution of the present application, when the rotary hook is at the point where the thread needs to be pulled to the maximum, the speed of the sewing machine main shaft will be increased, and the speed of the sewing machine main shaft will usually be increased rapidly in the following text, so that the thread take-up lever begins to accelerate and recover the thread, reducing the thread supply, so that the thread loop will not be entangled or knotted in the air, thereby avoiding the formation of a loose thread. For example, in the embodiment of Table 1, when the rotary hook is at the point where the thread needs to be pulled to the maximum, the speed is the third speed of 2700 RPM. The present application will increase the speed of the main shaft. As the rotary hook continues to move, when the suture thread is unthreaded, the speed of the main shaft has reached 2994.1 RPM, which means that the thread take-up speed of the thread take-up lever is increased, the thread supply is reduced, and the formation of a loose thread is avoided.

[0063] Step S104: When the thread take-up lever starts to drop from the highest point, the speed of the sewing machine main shaft is reduced until the rotary hook is at the thread hooking point, and the speed of the sewing machine main shaft is controlled to reach the first speed.

[0064] When the rotary hook is at the point of maximum thread demand, the sewing machine spindle speed is increased. Then, when the thread take-up lever reaches its highest point, the spindle speed reaches its maximum speed, i.e., the preset second speed. The second speed is the maximum speed during one rotation of the sewing machine spindle. The specific value of the second speed can be set according to actual needs. In Table 1, it is set to 3700 RPM.

[0065] After the thread take-up lever reaches its highest point, it begins to descend from its highest point, and the present application begins to reduce the spindle speed of the sewing machine. In the embodiment of Table 1, when the needle tip is piercing the material, the spindle speed is reduced to 3600 RPM. When the needle bar is at its lowest position, the spindle speed is reduced to 2733.3 RPM. When the rotary hook is at the thread hooking point, the spindle speed of the sewing machine reaches the lowest first speed of 2500 RPM, and the next rotation cycle begins.

[0066] It can be seen that when the rotary hook is at the position of the maximum thread demand point, the speed of the sewing machine main shaft is increased until the maximum second speed is reached when the sewing machine thread take-up rod reaches the highest point, which is conducive to making the average speed of the sewing machine main shaft higher during one rotation.

[0067] In addition, it should be noted that the process of the shuttle moving from the position of the thread hooking point to the position of the maximum thread demand point accounts for a low proportion in one rotation cycle. Therefore, the low speed of this process has little effect on the average speed of the sewing machine main shaft during one rotation.

[0068] In the present application, when the rotary hook is at the point where the thread is most needed, the speed of the sewing machine main shaft needs to be increased until the thread take-up lever of the sewing machine reaches its highest point, at which point the speed of the sewing machine main shaft is controlled to reach the second maximum speed. This acceleration process can be uniform acceleration or variable acceleration. In a specific embodiment of the present invention, considering that uniform acceleration is easy to implement and related programs are easy to design, step S103 can specifically include: from the point where the rotary hook is at the point where the thread is most needed to the point where the thread take-up lever of the sewing machine reaches its highest point, controlling the speed of the sewing machine main shaft to increase from the third speed to the second speed according to a fixed second acceleration.

[0069] See Figure 2a From the time when the rotary hook is at the point where the maximum thread demand is reached to the time when the thread take-up rod of the sewing machine reaches the highest point, a uniform acceleration implementation method is adopted.

[0070] Furthermore, in a specific embodiment of the present invention, step S103 may specifically include:

[0071] In the process from when the rotary hook is at the maximum thread demand point to when the thread take-up rod of the sewing machine reaches the highest point, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is reduced in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is gradually reduced.

[0072] See Figure 2b This embodiment adopts a variable acceleration embodiment, and this embodiment takes into account that the cause of the formation of the throw point is that the suture is twisted or knotted due to interference when it is in a suspended position. In this regard, the measure of the present application is to increase the speed of the sewing machine main shaft when the rotary hook is at the position of the maximum thread demand point, so that the thread take-up lever begins to accelerate and recover the thread, reducing the thread supply. Therefore, when the rotary hook is at the position of the maximum thread demand point, the faster the speed is increased, the more conducive it is to avoid the formation of the throw point. Therefore, this embodiment controls the speed of the sewing machine main shaft from the third speed to the second speed according to the rule of stepwise reduction of the absolute value of the speed change rate of the sewing machine main shaft, or according to the rule of gradually reducing the absolute value of the speed change rate of the sewing machine main shaft.

[0073] That is to say, in this embodiment, when the rotary hook is at the position of the maximum thread demand point, the rate of change of the rotational speed is the largest, so that the rotational speed can be quickly increased, and then the rate of change of the rotational speed is gradually reduced or reduced in stages until the spindle speed is increased to the second speed when the thread take-up lever of the sewing machine reaches the highest point.

[0074] Moreover, since the rotation speed of the main shaft is quickly increased after the rotary hook is at the position of the maximum thread demand point, it is also beneficial to increase the average rotation speed of the sewing machine main shaft during one rotation.

[0075] In addition, it should be noted that in the process from the time when the hook is at the maximum thread demand point to the time when the thread take-up rod of the sewing machine reaches the highest point, since the speed increases, the speed change rate of the sewing machine main shaft is a positive number, that is, the numerical value of the speed change rate of the sewing machine main shaft is equal to the absolute value of the speed change rate of the sewing machine main shaft.

[0076] exist Figure 2b In an embodiment, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft gradually decreases.

[0077] In a specific embodiment of the present invention, when the thread take-up lever descends from its highest point until the rotary hook is at the thread hooking point, the application requires reducing the speed of the sewing machine main shaft from the second maximum speed to the first minimum speed. This speed reduction process can be a uniform deceleration or a variable deceleration.

[0078] In a specific embodiment of the present invention, step S104 may specifically include: in the process of the thread take-up lever descending from the highest point until the shuttle is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to a fixed third acceleration.

[0079] This implementation method adopts a uniform deceleration method, that is, the speed of the sewing machine main shaft is reduced from the second speed to the first speed according to a fixed third acceleration, which is easy to implement and the related program is easy to design. Figure 2a In this acceleration process, the method of uniform deceleration is adopted.

[0080] In a specific embodiment of the present invention, step S104 may specifically include:

[0081] In the process of the thread take-up lever descending from the highest point until the rotary hook is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first increased in stages and then decreased in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first gradually increased and then gradually decreased.

[0082] In this embodiment, considering that the position of the thread take-up lever just begins to drop from the highest point, the main shaft can be kept at a higher speed, which is beneficial to improving the average speed of the sewing machine main shaft during one rotation. When the rotary shuttle is almost at the thread hooking point, if the main shaft speed changes too much, it will easily lead to an increase in the degree of thread shaking, which is not conducive to ensuring the stability of sewing. Therefore, when the rotary shuttle is almost at the thread hooking point, the main shaft speed should be close to the first speed, that is, the deceleration of the speed at this time should be lower.

[0083] In this regard, in this embodiment, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first increased in stages and then decreased in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first gradually increased and then gradually decreased.

[0084] That is, at the beginning of deceleration, the speed deceleration is set to a small value, so that the average speed of the sewing machine spindle during one rotation is high. Subsequently, the spindle speed is quickly reduced by increasing the deceleration. Finally, when the rotary hook is about to reach the thread hooking point, the deceleration is small, so that the spindle speed gradually reaches the minimum first speed.

[0085] exist Figure 2b In this deceleration process, the absolute value of the speed change rate of the sewing machine main shaft first gradually increases and then gradually decreases.

[0086] In addition, the solution of the present application can be applied to sewing machines with large rotary hooks or small rotary hooks, and the specific structure of the sewing machine can also be set and selected according to actual conditions without affecting the implementation of the present invention. Figure 3 Schematic diagram of the mechanism of a sewing machine in a specific embodiment, showing a rotary hook 10, a needle bar 20, a main shaft 30 and a thread take-up lever 40. Figure 3 The scale markings shown are for auxiliary measurement purposes and are not required in actual use. In one specific scenario, the spindle 30 can be set to rotate clockwise, with one rotation consisting of 360°. For example, when the needle bar 20 is at its lowest point, the phase angle of the spindle 30 is set to 172.8°. The thread take-up lever 40 is mounted on the spindle 30 and rotates once through 360°. The hook shaft is linked to the spindle 30, rotating at twice the speed of the spindle 30 and in the opposite direction.

[0087] By applying the technical solution provided by the embodiment of the present invention, when the rotary hook of the sewing machine is at the thread hooking point, the speed of the sewing machine main shaft is controlled to a preset first speed. The first speed is the minimum speed during one rotation of the sewing machine main shaft. In other words, the main shaft speed is the lowest when the rotary hook is hooking the thread. In this way, the hook tip of the rotary hook is less likely to cut the suture thread, thereby reducing the probability of thread breakage. After the rotary hook is at the point where the thread is most needed, as the rotary hook moves, the suture thread will be separated from the lower shuttle bed and the guide wire sheet of the rotary hook due to the action of external forces, that is, the suture thread is in a suspended position. Therefore, the thread loop is easily disturbed and twisted or knotted, forming a throw point. In this regard, in the solution of the present application, when the rotary hook is at the point where the thread is most needed, the speed of the sewing machine main shaft is increased, causing the thread take-up rod to accelerate and rise to rewind the thread, thereby reducing the thread supply, which is conducive to preventing the thread loop from getting tangled and knotted in the air, thereby reducing the probability of throw points. After the rotary hook reaches the maximum thread demand point, the spindle speed continuously increases until, when the thread take-up lever of the sewing machine reaches its highest point, the spindle speed reaches a preset second speed, thereby increasing the average spindle speed during one rotation of the sewing machine spindle. As the thread take-up lever descends from its highest point, the spindle speed can be reduced until, when the rotary hook reaches the thread hook point, the spindle speed is controlled to reach the first speed.

[0088] In summary, the solution of the present application reduces the probability of thread throw and thread breakage while ensuring a high average speed during one rotation of the sewing machine main shaft.

[0089] Corresponding to the above method embodiment, an embodiment of the present invention further provides a speed control system for a sewing machine, which can be referred to in correspondence with the above.

[0090] The speed control system of the sewing machine may include:

[0091] A low-speed control module is used to control the speed of the sewing machine main shaft to a preset first speed when the rotary hook of the sewing machine is at the thread hooking point;

[0092] The speed increasing module is used to control the speed of the sewing machine main shaft according to a preset rule when the rotary hook moves from the position of the thread hooking point to the position of the maximum thread demand point. When the rotary hook is at the position of the maximum thread demand point, the speed of the sewing machine main shaft is increased until the speed of the sewing machine main shaft reaches a preset second speed when the thread take-up lever of the sewing machine reaches the highest point.

[0093] a speed reducing module, configured to reduce the speed of the sewing machine main shaft when the thread take-up lever begins to descend from its highest point, until the speed of the sewing machine main shaft reaches a first speed when the rotary hook is at the thread hooking point;

[0094] The first speed is the minimum speed during one rotation of the sewing machine main shaft, and the second speed is the maximum speed during one rotation of the sewing machine main shaft.

[0095] In a specific embodiment of the present invention, the speed increasing module controls the speed of the sewing machine spindle according to a preset rule during the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, specifically for:

[0096] During the process of the rotary hook moving from the position at the thread hooking point to the position at the maximum thread demand point, the speed of the sewing machine main shaft is controlled to increase from the first speed to the preset third speed;

[0097] Among them, the third speed is greater than the first speed, and the third speed is less than the second speed, and the third speed satisfies: V3<(V1+V2) / 2, V1, V2 and V3 respectively represent the values ​​of the first speed, the second speed and the third speed.

[0098] In a specific embodiment of the present invention, the speed increasing module controls the speed of the sewing machine main shaft to increase from the first speed to a preset third speed, specifically for:

[0099] According to the fixed first acceleration, the rotation speed of the sewing machine main shaft is controlled to increase from the first rotation speed to a preset third rotation speed.

[0100] In a specific embodiment of the present invention, the speed increasing module controls the speed of the sewing machine main shaft to increase from the first speed to a preset third speed, specifically for:

[0101] According to the variable acceleration control method, the rotational speed of the sewing machine main shaft is controlled to increase from the first rotational speed to the preset third rotational speed.

[0102] In a specific embodiment of the present invention, the speed increasing module increases the speed of the sewing machine main shaft when the rotary hook is at the position of the maximum thread demand point until the thread take-up lever of the sewing machine reaches the highest point, thereby controlling the speed of the sewing machine main shaft to reach a preset second speed, specifically for:

[0103] In the process from when the rotary hook is at the maximum thread demand point to when the thread take-up rod of the sewing machine reaches the highest point, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to the fixed second acceleration.

[0104] In a specific embodiment of the present invention, the speed increasing module increases the speed of the sewing machine main shaft when the rotary hook is at the position of the maximum thread demand point until the thread take-up lever of the sewing machine reaches the highest point, thereby controlling the speed of the sewing machine main shaft to reach a preset second speed, specifically for:

[0105] In the process from when the rotary hook is at the maximum thread demand point to when the thread take-up rod of the sewing machine reaches the highest point, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is reduced in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is gradually reduced.

[0106] In a specific embodiment of the present invention, the speed reduction module is specifically used to:

[0107] During the process of the thread take-up lever descending from the highest point until the rotary hook is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the fixed third acceleration.

[0108] In a specific embodiment of the present invention, the speed reduction module is specifically used to:

[0109] In the process of the thread take-up lever descending from the highest point until the rotary hook is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first increased in stages and then decreased in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first gradually increased and then gradually decreased.

[0110] Corresponding to the above method and system embodiments, embodiments of the present invention further provide a speed control device for a sewing machine and a computer-readable storage medium, which may be referenced in conjunction with the above. The speed control device for a sewing machine may include:

[0111] memory for storing computer programs;

[0112] A processor is used to execute a computer program to implement the steps of the speed control method for a sewing machine in any of the above embodiments.

[0113] The computer-readable storage medium stores a computer program, and when the computer program is executed by the processor, the computer program implements the steps of the sewing machine speed control method in any of the above embodiments. The computer-readable storage medium herein includes random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, register, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0114] It should also be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0115] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0116] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only intended to help understand the technical solutions and core concepts of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications also fall within the scope of protection of the present invention.

Claims

1. A method for controlling the rotation speed of a sewing machine, characterized in that: include: When the rotary hook of the sewing machine is at the thread hooking point, the speed of the main shaft of the sewing machine is controlled to be a preset first speed; During the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, the speed of the sewing machine main shaft is controlled according to a preset rule; When the rotary hook is at the position of the maximum thread demand point, the speed of the sewing machine main shaft is increased until the thread take-up lever of the sewing machine reaches the highest point, and the speed of the sewing machine main shaft is controlled to reach a preset second speed; When the thread take-up lever begins to descend from its highest point, the speed of the sewing machine main shaft is reduced until the rotary hook is at the thread hooking point, and the speed of the sewing machine main shaft is controlled to reach the first speed; The first speed is the minimum speed during one rotation of the sewing machine main shaft, and the second speed is the maximum speed during one rotation of the sewing machine main shaft. During the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, the speed of the sewing machine main shaft is controlled according to a preset rule, including: During the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, controlling the rotation speed of the sewing machine main shaft to increase from the first rotation speed to a preset third rotation speed; The third speed is greater than the first speed and less than the second speed, and the third speed satisfies the following conditions: V3 < (V1 + V2) / 2, where V1, V2, and V3 represent the values ​​of the first speed, the second speed, and the third speed, respectively. When the rotary hook is at the maximum thread demand point, the rotation speed of the sewing machine main shaft is increased until the thread take-up lever of the sewing machine reaches the highest point, and the rotation speed of the sewing machine main shaft is controlled to reach a preset second rotation speed, including: During the period from when the rotary hook is at the maximum thread demand point to when the thread take-up lever of the sewing machine reaches the highest point, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to a rule that the absolute value of the speed change rate of the sewing machine main shaft is reduced in stages, or according to a rule that the absolute value of the speed change rate of the sewing machine main shaft is gradually reduced; When the thread take-up lever begins to descend from its highest point, the speed of the sewing machine main shaft is reduced until the rotary hook is at the thread hooking point, and the speed of the sewing machine main shaft is controlled to reach the first speed, comprising: In the process of the thread take-up lever descending from the highest point until the rotary hook is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first increased in stages and then decreased in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first gradually increased and then gradually decreased.

2. The method for controlling the rotation speed of a sewing machine according to claim 1, wherein: Controlling the rotation speed of the sewing machine main shaft to increase from the first rotation speed to a preset third rotation speed includes: According to a fixed first acceleration or a variable acceleration control method, the rotational speed of the sewing machine main shaft is controlled to increase from the first rotational speed to a preset third rotational speed.

3. The method for controlling the rotation speed of a sewing machine according to claim 1, wherein: When the rotary hook is at the maximum thread demand point, the rotation speed of the sewing machine main shaft is increased until the thread take-up lever of the sewing machine reaches the highest point, and the rotation speed of the sewing machine main shaft is controlled to reach a preset second rotation speed, including: In the process from when the rotary hook is at the maximum thread demand point to when the thread take-up lever of the sewing machine reaches the highest point, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to the fixed second acceleration.

4. The method for controlling the rotation speed of a sewing machine according to any one of claims 1 to 3, wherein: When the thread take-up lever begins to descend from its highest point, the speed of the sewing machine main shaft is reduced until the rotary hook is at the thread hooking point, and the speed of the sewing machine main shaft is controlled to reach the first speed, comprising: During the process of the thread take-up lever descending from the highest point until the rotary hook is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the fixed third acceleration.

5. A speed control system for a sewing machine, characterized in that: include: A low-speed control module is used to control the speed of the sewing machine main shaft to a preset first speed when the rotary hook of the sewing machine is at the thread hooking point; a speed increasing module, configured to control the speed of the sewing machine main shaft according to a preset rule when the rotary hook moves from the position of the thread hooking point to the position of the maximum thread demand point, and to increase the speed of the sewing machine main shaft when the rotary hook is at the position of the maximum thread demand point until the speed of the sewing machine main shaft reaches a preset second speed when the thread take-up lever of the sewing machine reaches the highest point; a speed reducing module, configured to reduce the speed of the sewing machine main shaft when the thread take-up lever begins to descend from its highest point, until the speed of the sewing machine main shaft reaches the first speed when the rotary hook is at the thread hooking point; The first speed is the minimum speed during one rotation of the sewing machine main shaft, and the second speed is the maximum speed during one rotation of the sewing machine main shaft. During the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, the speed of the sewing machine main shaft is controlled according to a preset rule, including: During the process of the rotary hook moving from the position of the thread hooking point to the position of the maximum thread demand point, controlling the rotation speed of the sewing machine main shaft to increase from the first rotation speed to a preset third rotation speed; The third speed is greater than the first speed and less than the second speed, and the third speed satisfies the following conditions: V3 < (V1 + V2) / 2, where V1, V2, and V3 represent the values ​​of the first speed, the second speed, and the third speed, respectively. When the rotary hook is at the maximum thread demand point, the rotation speed of the sewing machine main shaft is increased until the thread take-up lever of the sewing machine reaches the highest point, and the rotation speed of the sewing machine main shaft is controlled to reach a preset second rotation speed, including: During the period from when the rotary hook is at the maximum thread demand point to when the thread take-up lever of the sewing machine reaches the highest point, the speed of the sewing machine main shaft is controlled to increase from the third speed to the second speed according to a rule that the absolute value of the speed change rate of the sewing machine main shaft is reduced in stages, or according to a rule that the absolute value of the speed change rate of the sewing machine main shaft is gradually reduced; When the thread take-up lever begins to descend from its highest point, the speed of the sewing machine main shaft is reduced until the rotary hook is at the thread hooking point, and the speed of the sewing machine main shaft is controlled to reach the first speed, comprising: In the process of the thread take-up lever descending from the highest point until the rotary hook is at the thread hooking point, the speed of the sewing machine main shaft is controlled to decrease from the second speed to the first speed according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first increased in stages and then decreased in stages, or according to the rule that the absolute value of the speed change rate of the sewing machine main shaft is first gradually increased and then gradually decreased.

6. A speed control device for a sewing machine, characterized in that: include: Memory for storing computer programs; A processor is used to execute the computer program to implement the steps of the sewing machine speed control method according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for controlling the rotational speed of a sewing machine according to any one of claims 1 to 4 are implemented.

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