A method and system for online monitoring of instantaneous pressure of a button machine

Abstract

The application provides a kind of instantaneous pressure online monitoring method and system of buckle machine, the method comprises: current acquisition and signal processing module real-time acquisition motor three-phase current;According to three-phase current, current vector control algorithm, real-time calculation motor output torque.Calculation motor output torque according to current acquisition and signal processing module, motor output pressure is applied to the end of button vertically by tool after motor output torque.Caution analysis and output module, in pre-stored or learn different button model corresponding pressure threshold range;Caution analysis and output module real-time acquisition motor output pressure;Caution analysis and output module, in the process of buttoning, whether the motor output pressure received in real time exceeds pressure threshold range;When real-time buttoning pressure exceeds the upper limit of pressure threshold range or lower than the lower limit of pressure threshold range, caution analysis and output module trigger alarm signal.

Description

Technical Field

[0001] This invention relates to the field of online monitoring methods for instantaneous mechanical pressure, and more particularly to a method and system for online monitoring of instantaneous pressure in a button machine. Background Technology

[0002] Button sewing machines are key pieces of equipment in garment production, used to quickly and securely sew buttons onto clothing. In existing technology, the die pressure of a button sewing machine is typically preset by a mechanical spring or pneumatic device and remains constant over a relatively long work cycle. This fixed pressure mode has the following significant drawbacks:

[0003] Poor adaptability: It cannot automatically adapt to buttons of different thicknesses, materials (such as metal, resin, shell), and shapes (such as two-hole, four-hole, and footed buttons). Insufficient pressure may cause buttons to loosen; excessive pressure may crush brittle buttons (such as resin buttons), or cause needle misalignment, breakage, or even damage to the die on high-hardness buttons. Unstable quality: With changes in processing batches, fabric thickness, or slight machine wear, the preset pressure may no longer be optimal, leading to loose buttons and a decrease in product qualification rate. Lack of process monitoring: Operators cannot perceive the actual pressure during the button-sewing process in real time, and can only passively discover defects after they occur, resulting in material waste and production interruptions. Adjustment relies on experience: Pressure adjustment depends entirely on the operator's experience, which has a high learning cost for novices and makes it difficult to ensure consistency.

[0004] Therefore, developing an online instantaneous pressure monitoring method and system for button machines, capable of real-time monitoring of the instantaneous pressure acting on buttons and adaptive adjustment or early warning based on the results, to improve button quality, equipment reliability and production efficiency, has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] To address the aforementioned technical deficiencies, this invention collects the three-phase current of the servo motor during operation, combines it with a vector control algorithm, calculates the output pressure acting on the button during the button-attaching process in real time, and monitors it by comparing the output pressure with the pressure threshold range. This enables adaptive adjustment of the button-attaching pressure based on different buttons and provides online early warning.

[0006] This invention provides a method for online monitoring of instantaneous pressure in a button-making machine, comprising:

[0007] The current acquisition and signal processing module acquires the three-phase current of the motor in real time; and calculates the motor output torque in real time based on the three-phase current and current vector control algorithm.

[0008] The current acquisition and signal processing module calculates the motor output torque based on the motor output torque and then applies the motor output pressure perpendicularly to the button end through the mold.

[0009] The early warning analysis and output module pre-stores or learns the pressure threshold range corresponding to different button models; the early warning analysis and output module acquires the motor output pressure in real time;

[0010] The early warning analysis and output module determines in real time whether the received motor output pressure exceeds the pressure threshold range during the fastening process.

[0011] When the real-time snapping pressure is determined to exceed the upper limit of the pressure threshold range or fall below the lower limit of the pressure threshold range, the early warning analysis and output module triggers an alarm signal.

[0012] Optionally, the current acquisition and signal processing module calculates the motor output torque in real time based on the three-phase current and current vector control algorithm, specifically including:

[0013] Using the aforementioned current vector control algorithm, the three-phase current is transformed into a rotating coordinate system through coordinate transformation, and the three-phase current is decomposed into excitation current and torque current I used to generate output torque. q ;

[0014] Based on equation (1) and the torque current I q The output torque of the motor is calculated as follows:

[0015] T 电机 = K t *I q Equation (1);

[0016] Among them, K t This is the torque coefficient.

[0017] Optionally, the current acquisition and signal processing module, based on the motor output torque, calculates the motor output torque and then applies the motor output pressure perpendicularly to the button end through the mold, specifically including:

[0018] Using equation (2), and based on the calibration coefficient η of the button machine transmission mechanism and the output torque T of the motor... 电机 Calculate the actual torque acting on the button end:

[0019] T=T 电机 η; Equation (2);

[0020] The motor output pressure is calculated in real time based on the actual torque T acting on the button end, which is obtained in real time.

[0021] Optionally, the step of calculating the motor output pressure in real time based on the actual torque acting on the button end, which is obtained in real time, specifically includes:

[0022] Based on the real-time acquired actual torque T acting on the button end, the motor output pressure is calculated in real time using a centering crank-slider mechanism:

[0023] Equation (3);

[0024] Where a represents the motor rotation angle; r represents the rotation radius of the motor; and λ represents the link ratio.

[0025] Optionally, the current acquisition and signal processing module extracts the effective motor output torque from the motor output torque in real time and calculates the actual motor output pressure acting perpendicularly on the button end; the effective motor output torque represents the range of motor output torque after excluding the motor rotational inertia.

[0026] Optionally, the effective motor output torque is the range of motor output torque calculated based on the range of ±45° from the bottom dead center of the motor rotation trajectory in the centering crank-slider mechanism.

[0027] Optionally, the method further includes:

[0028] Before the button-attaching machine starts working, the human-machine interface module sets the pressure threshold range corresponding to the button to be produced and transmits it to the early warning analysis and output module.

[0029] During the fastening process, the early warning analysis and output module determines in real time whether the received motor output pressure exceeds the set pressure threshold range.

[0030] The present invention also provides an online instantaneous pressure monitoring system for a button machine, used to implement the online instantaneous pressure monitoring method for a button machine as described in any of the preceding claims, the system comprising:

[0031] The current acquisition and signal processing module is used to acquire the three-phase current of the motor in real time, and calculate the motor output torque in real time based on the three-phase current and the current vector control algorithm; and is used to: calculate the motor output torque based on the motor output torque and then apply the motor output pressure perpendicularly to the button end through the mold.

[0032] The early warning analysis and output module pre-stores or learns the pressure threshold range corresponding to different button models; the early warning analysis and output module is used to acquire the motor output pressure in real time; and is used to: determine in real time whether the received motor output pressure exceeds the pressure threshold range during the button sewing process; when the real-time button sewing pressure exceeds the safe upper limit of the pressure threshold range or falls below the lower limit of the pressure threshold range, the early warning analysis and output module triggers an alarm signal.

[0033] Optionally, the current acquisition and signal processing module is used to extract the effective motor output torque from the motor output torque in real time and calculate the actual motor output pressure acting perpendicularly on the button end; the effective motor output torque represents the range of motor output torque after excluding the motor rotational inertia.

[0034] Optionally, the instantaneous pressure online monitoring system for the button machine further includes:

[0035] The human-machine interface module is used to set the pressure threshold range corresponding to the button to be produced before the button attaching machine starts working, and transmit it to the early warning analysis and output module.

[0036] The early warning analysis and output module is used to determine in real time whether the received motor output pressure exceeds the set pressure threshold range during the fastening process.

[0037] Compared with existing technologies, the above technical solution has the following advantages:

[0038] 1. This invention is the first to propose a pressure monitoring scheme for buttons applied by a mold driven by a servo motor. By collecting the three-phase current of the servo motor and combining it with a vector control algorithm, the output pressure acting on the button during the button-attaching process is calculated in real time and compared with the pressure threshold range. This enables adaptive adjustment of the button-attaching pressure according to different buttons and online early warning.

[0039] 2. The corresponding motor output torque range within ±45° of the bottom dead center of the crank-slider mechanism is collected for output pressure calculation. This avoids interference from the motor's rotational inertia on torque calculation, thus more accurately determining the motor output pressure range and improving the reliability of motor output pressure analysis.

[0040] 3. This invention is an automated online instantaneous pressure monitoring method and system for button sewing machines, which reduces reliance on operator experience, shortens machine setup time, and improves the intelligence level and production efficiency of button sewing machines. Attached Figure Description

[0041] Figure 1 This is a flowchart illustrating an online instantaneous pressure monitoring method for a button machine according to an embodiment of the present invention;

[0042] Figure 2 This is a structural diagram of a button-making machine according to an embodiment of the present invention;

[0043] Figure 3 It is a curve showing the change of torque with motor position according to an embodiment of the present invention;

[0044] Figure 4It is a curve showing the actual motor torque acting on the button end as a function of motor position, according to an embodiment of the present invention.

[0045] Figure 5 This is a schematic diagram of a model in which the rotational motion of a motor, conforming to an embodiment of the present invention, is converted into linear motion through a crank-slider mechanism. Figure 1 ;

[0046] Figure 6 This is a schematic diagram of a model in which the rotational motion of a motor, conforming to an embodiment of the present invention, is converted into linear motion through a crank-slider mechanism. Figure 2 ;

[0047] Figure label:

[0048] 1-Upper clamp mold;

[0049] 2-Lower clamping mold;

[0050] 3-Left vibrating disc;

[0051] 4-Right vibrating disc;

[0052] 5- Fabric placement area;

[0053] 7- Touchscreen;

[0054] 8-Foot pedal. Detailed Implementation

[0055] The advantages of the present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments.

[0056] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0057] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0058] In the description of this invention, it should be understood that the terms "inner" and "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0059] In the description of this invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0060] In the following description, suffixes such as "module," "part," or "unit" used to denote elements are used only for the convenience of the description of the invention and have no specific meaning in themselves. Therefore, "module" and "part" can be used interchangeably.

[0061] Figure 1 A method for online instantaneous pressure monitoring of a button machine according to an embodiment of the present invention is shown. (See also...) Figure 1 The instantaneous pressure online monitoring method for the button machine includes: steps S1 to S4:

[0062] S1: The current acquisition and signal processing module acquires the three-phase current of the motor in real time; and calculates the motor output torque in real time based on the three-phase current and the current vector control algorithm.

[0063] S2: The current acquisition and signal processing module calculates the motor output torque based on the motor output torque and then applies the motor output pressure perpendicularly to the button end through the mold.

[0064] S3: Early warning analysis and output module, which pre-stores or learns the pressure threshold range corresponding to different button models; the early warning analysis and output module obtains the output pressure of the motor when the mold acts vertically on the button end in real time.

[0065] S4: The early warning analysis and output module determines in real time whether the received motor output pressure exceeds the pressure threshold range during the fastening process; when the real-time fastening pressure exceeds the safe upper limit of the pressure threshold range or is lower than the lower limit of the pressure threshold range, the early warning analysis and output module triggers an alarm signal.

[0066] Against the backdrop of the significant challenges in monitoring instantaneous pressure changes during research and development, this invention proposes for the first time a mold-based button pressure monitoring solution suitable for servo motor drives. By collecting the three-phase current of the servo motor during operation and combining it with a vector control algorithm, this invention can calculate the output pressure acting on the button end in real time during the button-attaching process, achieving precise monitoring of instantaneous pressure changes. The early warning analysis and output module collects the output pressure and, based on a preset correspondence between button models and pressure thresholds, performs pressure monitoring and early warning. This enables adaptive pressure monitoring and early warning for buttons of different materials and structures, avoiding button breakage or needle breakage due to excessive pressure, and weak sewing due to insufficient pressure. The system can sense the actual pressure during the button-attaching process in real time, promptly detecting changes in button quality and avoiding material waste; it achieves automated button-attaching monitoring.

[0067] In a further optional embodiment of the present invention, the instantaneous pressure online monitoring method for the button-making machine further includes: Step S0: Before the button-making machine starts working, the human-machine interface module sets the pressure threshold range corresponding to the button to be produced and transmits it to the early warning analysis and output module. During the button-making process, the early warning analysis and output module determines in real time whether the received motor output pressure exceeds the set pressure threshold range corresponding to the button to be produced. When the real-time pressure exceeds the safety upper limit, the display screen of the human-machine interface module indicates that the pressure is too high, posing a risk of damage to the button or needle breakage; or when it is below the effective lower limit, the display screen indicates that the pressure is too low, posing a risk of loose stitching. The early warning analysis and output module then triggers an early warning signal. In this embodiment, by pre-setting the button-making pressure threshold range on the human-machine interface, the early warning analysis and output module performs pressure monitoring and early warning based on a preset correspondence between button models and pressure threshold ranges, achieving adaptive pressure monitoring for buttons of different materials and structures.

[0068] In a further preferred embodiment, the pre-stored correspondence table of different "button models - pressure threshold ranges" in the early warning analysis and output module is adjusted and updated according to actual needs to adapt to changes in processing batches, fabric thickness, or slight machine wear, thereby improving the reliability of pressure monitoring and early warning.

[0069] Optionally, in step S1, the step of the current acquisition and signal processing module calculating the motor output torque in real time based on the three-phase current and current vector control algorithm specifically includes steps S11~S12:

[0070] S11: Using a current vector control algorithm, the three-phase current is transformed into a rotating coordinate system through coordinate transformation, and the three-phase current is decomposed into excitation current and torque current I used to generate output torque. q .

[0071] S12: Based on equation (1) and the torque current I q The output torque of the motor is calculated as: T 电机 = K t *I q Equation (1); where K t This is the torque coefficient. Figure 3 This is a graph showing the change in torque as a function of the motor's rotational position, according to an embodiment of the present invention. The torque changes with the motor's rotational position during the process of starting the snap fastener, pressing the fastener, and finishing the snap fastener operation, as shown below. Figure 3 As shown, the horizontal axis represents the motor position, which is the current rotation angle of the motor, with one mechanical angle being 360 degrees; the vertical axis represents the motor position.

[0072] In practice, the torque of the motor during idling is not zero, and at this time, the torque does not act on the button. Therefore, to more accurately monitor the pressure acting on the button, the torque signal can be processed in conjunction with the actual position of the mold. Only the torque when the mold reaches the button-attaching position can actually act on the button. The distance between the mold reaching the button-attaching position and the position where the button leaves is not a single point, but a range. The size of this range is related to the pressure; the greater the pressure, the larger the range, and vice versa. In a further optional embodiment, the button position can be monitored by setting a position monitoring sensor or other solutions. This invention does not limit this; any solution that can achieve mold position monitoring is within the protection scope of this invention.

[0073] In a preferred embodiment, the motor output torque obtained in step S1 is compensated and corrected. Specifically, compensation is needed for motor temperature rise (current detection error caused by resistance change), iron loss, mechanical friction and other losses. The current value is dynamically corrected through an algorithm to improve torque accuracy.

[0074] Furthermore, since the torque output of the servo motor, calculated from the torque of the mechanical transmission chain, needs to be transmitted to the mold through transmission components such as a gearbox, coupling, and main shaft, and ultimately acts on the button, the transmission efficiency needs to be determined in advance through calibration (measured at the chuck end using a standard torque sensor and compared with the motor torque for calibration). Therefore, in a further preferred embodiment of the present invention, step S2: the step of the current acquisition and signal processing module calculating the motor output torque based on the motor output torque and then applying the motor output pressure perpendicularly to the button end through the mold includes steps S21 to S22:

[0075] S21: Using formula (2), and based on the calibration coefficient η of the button machine transmission mechanism and the output torque T of the motor. 电机 Calculate the actual torque acting on the button end: T = T 电机η; Equation (2). The obtained curve graph of the actual acting torque on the button end varying with the motor position, for the specific curve, refer to Figure 4 . Among them, the abscissa P is the angle of current motor rotation, and one mechanical angle cycle is 360 degrees; the ordinate is: the motor torque T acting on the button end. The upper and lower "convex" - shaped structures in the figure represent the upper button and the lower button, and the structure between the upper button and the lower button is the schematic diagram of the fabric structure.

[0076] S22: According to the actually obtained acting torque on the button end in real - time, calculate the motor output pressure in real - time.

[0077] Through compensating and calibrating the motor temperature rise, mechanical friction and transmission efficiency, the present invention improves the accuracy of the torque calculation of the mold end acting on the button, so that the finally calculated pressure data can truly reflect the force state of the button.

[0078] Figures 5-6 It is a model schematic diagram of the rotational motion of the motor in accordance with an embodiment of the present invention being converted into linear motion through a centric crank - slider mechanism Figure 1 schematic Figure 2 ; schematic diagrams representing different rotational positions of the motor. In the figure, A represents the top dead center, point B represents the bottom dead center, r represents the radius of rotation, and l represents the linear distance between the rotating end and the centric crank - slider mechanism.

[0079] Refer to Figures 5-6 , optionally, in step S2: The step of calculating the motor output pressure in real - time according to the actually obtained acting torque on the button end in real - time specifically includes: According to the actually obtained acting torque T on the button end in real - time, using the centric crank - slider mechanism and Equation (3), calculate the motor output pressure T in real - time:

[0080] ; Equation (y); where, a represents the motor rotation angle (the top dead center is 0 degrees); λ represents the connecting - rod ratio; r represents the radius of rotation.

[0081] In order to avoid the influence of acceleration and deceleration inertia, in a further preferred solution of the present invention, step S2 specifically includes: The current acquisition and signal - processing module extracts the effective motor output torque in the motor output torque in real - time, and calculates the actual motor output pressure of the motor acting vertically on the button end; the effective motor output torque represents the range of the motor output torque after excluding the motor rotation inertia.

[0082] Determined through multiple repeated experiments, in a further preferred solution, the effective motor output torque is: the range of the motor output torque within ± 45° at the bottom dead center of the motor rotation trajectory in the centric crank - slider mechanism (when the motor rotates to such as Figure 5 、 Figure 6The maximum output torque is reached at the lowest dead center B (bottom dead center) of the circular rotation trajectory.

[0083] This solution avoids interference from motor rotational inertia in pressure calculations, improving the reliability of pressure analysis and thus more accurately determining the motor's output pressure range. An alarm is triggered when the motor's output pressure exceeds the pressure threshold set for a specific button model, prompting a worker to adjust the machine and prevent batch defects.

[0084] The following is a brief description of the steps of an online monitoring method for instantaneous pressure of a snap fastener in a specific example: 1. Initialization: After the device is powered on, the control module reads the operating parameters from the storage unit and enters standby mode; 2. Parameter configuration: The operator selects the current operating condition (such as "torque upper limit, speed, etc.") via the touch screen; 3. Pressure detection: When the snap fastener is working, the pressure signal is collected in real time during the punch pressing process. After being processed by the signal conditioning unit, it is transmitted to the microcontroller, which analyzes it and converts it into a digital signal; 4. Anomaly judgment: The microcontroller compares the sampled pressure value with the pressure threshold range and calculates the pressure change rate (unit: N / ms); 5. If the pressure value is within the pressure threshold range and the change rate is normal, the device continues to work; If the pressure value exceeds the pressure threshold range (such as a sudden increase in pressure due to a stuck snap fastener), it is judged as abnormal; Warning and protection: When an abnormality occurs, the screen displays the fault content and the device stops, waiting for detection.

[0085] This invention also provides an online instantaneous pressure monitoring system for a button machine, used to implement the online instantaneous pressure monitoring method for the button machine as described in any of the preceding claims. The system includes: a current acquisition and signal processing module, used to acquire the three-phase current of the motor in real time, and calculate the motor output torque in real time based on the three-phase current and a current vector control algorithm; and used to: calculate the motor output torque based on the motor output torque and then apply it perpendicularly to the button end through a mold to generate the motor output pressure. An early warning analysis and output module, internally storing or learning pressure threshold ranges corresponding to different button models; the early warning analysis and output module is used to acquire the motor output pressure in real time; and used to: determine in real time whether the received motor output pressure exceeds the pressure threshold range during the button-attaching process; when the real-time button-attaching pressure exceeds the safe upper limit of the pressure threshold range or falls below the lower limit of the pressure threshold range, the early warning analysis and output module triggers an alarm signal.

[0086] The instantaneous online pressure monitoring system for button machines provided by this invention can achieve adaptive pressure monitoring and early warning for buttons of different materials and structures, avoiding problems such as button breakage or needle breakage due to excessive pressure, and poor sewing due to insufficient pressure.

[0087] The current acquisition and signal processing module specifically includes: a high-precision current sensor (phase line acquisition) integrated inside the driver, which can acquire the three-phase current of the motor in real time; the three-phase current is decomposed into excitation current (d-axis) and torque current (q-axis) through the "vector control" algorithm, wherein the q-axis current directly determines the output torque.

[0088] The current acquisition and signal processing module is used to calculate the motor output torque in real time based on the three-phase current and the current vector control algorithm. After calculating the motor output torque, the module applies the calculated motor output torque to the button end via a mold. Specifically, it uses the current vector control algorithm to transform the three-phase current into a rotating coordinate system through coordinate transformation, and decomposes the three-phase current into excitation current and torque current I used to generate the output torque. q ; and for use according to equation (1) and the torque current I q The output torque of the motor is calculated as follows: Tmotor = Kt * Imotor q Equation (1); where K t The torque coefficient is used. The output torque of the motor also needs to be compensated and corrected. Specifically, compensation is needed for motor temperature rise (resistance change leading to current detection error), iron loss, mechanical friction, and other losses. The current value is dynamically corrected through an algorithm to improve torque accuracy. Furthermore, the transmission efficiency needs to be determined in advance through calibration (measured at the chuck end using a standard torque sensor and compared with the motor torque for calibration). Using equation (2), and based on the calibration coefficient η of the button machine transmission mechanism and the output torque T of the motor... 电机 Calculate the actual torque acting on the button end: T = T 电机 η; Equation (2) Torque conversion of mechanical transmission chain The torque output of the servo motor needs to be transmitted to the mold through transmission components such as gearbox, coupling, and main shaft, and finally acted on the motor torque after the button. Based on the real-time obtained motor output torque, the motor output pressure is calculated in real time using the centering crank slider mechanism and Equation (3): Equation (3); where T represents the motor output torque; a represents the motor rotation angle (top dead center is 0 degrees); λ represents the connecting rod ratio; and r represents the rotation radius.

[0089] Optionally, the current acquisition and signal processing module further extracts the effective motor output torque from the motor output torque in real time and calculates the actual motor output pressure acting perpendicularly on the button end; the effective motor output torque represents the range of motor output torque after excluding motor rotational inertia. This avoids interference from motor rotational inertia on pressure calculation and improves the reliability of pressure analysis. This was determined through repeated experiments.

[0090] The effective motor output torque is the range of motor output torque within ±45° of the lower dead center of the motor rotation trajectory in the centering crank-slider mechanism.

[0091] Optionally, the instantaneous online pressure monitoring system for the button-making machine further includes: a human-machine interface module, used to set the pressure threshold range corresponding to the button to be produced before the button-making machine starts working, and transmit it to the early warning analysis and output module. The early warning analysis and output module is used to determine in real time whether the received motor output pressure exceeds the set pressure threshold range corresponding to the button to be produced during the button-making process. The pressure threshold (upper and lower limits) is set for the button to be produced through the human-machine interface module. During button-making, the pressure module continuously collects pressure signals, processes them, and transmits them to the early warning analysis and output module. The early warning analysis and output module extracts key features (such as peak pressure and stability during the pressure holding phase) based on the real-time pressure-motor position curve and compares them with the user-set thresholds. Once an anomaly is detected, an early warning is immediately triggered.

[0092] In a further embodiment, the early warning analysis and output module includes a parameter storage unit for pre-storing or learning different correspondence tables of "button type - pressure threshold range". With changes in processing batches, fabric thickness, or slight machine wear, the preset pressure threshold range may no longer be optimal, leading to loose buttons and a decrease in product qualification rate. The correspondence table of "button type - pressure threshold range" can be adjusted and updated according to actual needs to adapt to changes in processing batches, fabric thickness, or slight machine wear, thereby improving the reliability of pressure monitoring and early warning.

[0093] In addition to the above, the human-machine interface module also includes functions such as parameter setting, status display, pressure display, and alerts. The module also includes a touchscreen, which is used to select button models, view real-time pressure curves, and set pressure thresholds. When an alert is triggered, the device will stop, the screen will display the real-time pressure value, and an alarm will be generated.

[0094] Figure 2 This is a structural diagram of a button-making machine according to a specific example of the present invention. In this specific example, in addition to the above configuration, the button-making machine also includes, but is not limited to: a servo motor, an upper button mold 1 and a lower button mold 2 driven by the servo motor, a fabric placement area 5 between the upper button mold 1 and the lower button mold 2, a left vibrating plate 3, a right vibrating plate 4, a foot pedal 8, and a touch screen 7. The upper button mold 1 and the lower button mold 2 are both servo-driven. The position of the lower button mold 2 can be finely adjusted according to the force applied to ensure that the button-sewing pressure is within the required range.

[0095] In summary, this invention provides a method and system for online instantaneous pressure monitoring of a button sewing machine, and for the first time proposes a button pressure monitoring scheme suitable for servo motor drives. By collecting the servo motor's operating current and combining it with a vector control algorithm, the pressure acting on the button during the sewing process is calculated in real time, enabling adaptive adjustment of the sewing pressure based on different buttons and online early warning. Furthermore, by collecting the motor output torque range corresponding to ±45° at the bottom dead center of the crank-slider mechanism, the interference of motor rotational inertia on the actual torque is avoided, thus more accurately determining the motor output pressure range and improving the reliability of pressure analysis. In addition, this invention provides an automated online instantaneous pressure monitoring system for button sewing machines, reducing reliance on operator experience, shortening machine setup time, and improving the intelligence level and production efficiency of the button sewing machine.

[0096] It should be noted that the embodiments of the present invention have better implementability and are not intended to limit the present invention in any way. Any person skilled in the art may use the above-disclosed technical content to change or modify it into equivalent effective embodiments. However, any modifications or equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for online monitoring of instantaneous pressure in a button-making machine, characterized in that, include: The current acquisition and signal processing module acquires the three-phase current of the motor in real time; and calculates the motor output torque in real time based on the three-phase current and current vector control algorithm. The current acquisition and signal processing module calculates the motor output torque based on the motor output torque and then applies the motor output pressure perpendicularly to the button end through the mold. The early warning analysis and output module pre-stores or learns the pressure threshold range corresponding to different button models; the early warning analysis and output module acquires the motor output pressure in real time; The early warning analysis and output module determines in real time whether the received motor output pressure exceeds the pressure threshold range during the fastening process. When the real-time snapping pressure is determined to exceed the upper limit of the pressure threshold range or fall below the lower limit of the pressure threshold range, the early warning analysis and output module triggers an alarm signal.

2. The instantaneous pressure online monitoring method for a button machine as described in claim 1, characterized in that, The current acquisition and signal processing module calculates the motor output torque in real time based on the three-phase current and current vector control algorithm, specifically including the following steps: Using the aforementioned current vector control algorithm, the three-phase current is transformed into a rotating coordinate system through coordinate transformation, and the three-phase current is decomposed into excitation current and torque current I used to generate output torque. q ; Based on equation (1) and the torque current I q The output torque of the motor is calculated as follows: T 电机 = K t *I q Equation (1); Among them, K t This is the torque coefficient.

3. The instantaneous pressure online monitoring method for a button machine as described in claim 2, characterized in that, The current acquisition and signal processing module calculates the motor output torque based on the aforementioned motor output torque, and then applies the motor output pressure perpendicularly to the button end through the mold. Specifically, this includes: Using equation (2), and based on the calibration coefficient η of the button machine transmission mechanism and the output torque T of the motor... 电机 Calculate the actual torque acting on the button end: T=T 电机 η; Equation (2); The motor output pressure is calculated in real time based on the actual torque T acting on the button end, which is obtained in real time.

4. The instantaneous pressure online monitoring method for a button machine as described in claim 3, characterized in that, The step of calculating the motor output pressure in real time based on the actual torque acting on the button end, which is obtained in real time, specifically includes: Based on the real-time acquired actual torque T acting on the button end, the motor output pressure is calculated in real time using a centering crank-slider mechanism: Equation (3); Where a represents the motor rotation angle; r represents the rotation radius of the motor; and λ represents the link ratio.

5. The instantaneous pressure online monitoring method for a button machine as described in claim 4, characterized in that, The current acquisition and signal processing module extracts the effective motor output torque from the motor output torque in real time and calculates the actual motor output pressure acting perpendicularly on the button end; the effective motor output torque represents the range of motor output torque after excluding the motor rotational inertia.

6. The instantaneous pressure online monitoring method for a button machine as described in claim 5, characterized in that, The effective motor output torque is the range of motor output torque calculated based on the lower dead center of the motor rotation trajectory within ±45° in the centering crank-slider mechanism.

7. The instantaneous pressure online monitoring method for a button machine as described in claim 1, characterized in that, The method further includes: Before the button-attaching machine starts working, the human-machine interface module sets the pressure threshold range corresponding to the button to be produced and transmits it to the early warning analysis and output module. During the fastening process, the early warning analysis and output module determines in real time whether the received motor output pressure exceeds the set pressure threshold range.

8. A real-time pressure online monitoring system for a button machine, characterized in that, For implementing the instantaneous pressure online monitoring method for a button machine as described in any one of claims 1-7, the system comprises: The current acquisition and signal processing module is used to acquire the three-phase current of the motor in real time, and calculate the motor output torque in real time based on the three-phase current and the current vector control algorithm; and is used to: calculate the motor output torque based on the motor output torque and then apply the motor output pressure perpendicularly to the button end through the mold. The early warning analysis and output module pre-stores or learns the pressure threshold range corresponding to different button models; the early warning analysis and output module is used to acquire the motor output pressure in real time; and is used to: determine in real time whether the received motor output pressure exceeds the pressure threshold range during the button sewing process; when the real-time button sewing pressure exceeds the safe upper limit of the pressure threshold range or falls below the lower limit of the pressure threshold range, the early warning analysis and output module triggers an alarm signal.

9. The instantaneous pressure online monitoring system for a button machine as described in claim 8, characterized in that, The current acquisition and signal processing module is used to extract the effective motor output torque from the motor output torque in real time and calculate the actual motor output pressure acting perpendicularly on the button end; the effective motor output torque represents the range of motor output torque after excluding the motor rotational inertia.

10. The instantaneous pressure online monitoring system for a button machine as described in claim 9, characterized in that, Also includes: The human-machine interface module is used to set the pressure threshold range corresponding to the button to be produced before the button attaching machine starts working, and transmit it to the early warning analysis and output module. The early warning analysis and output module is used to determine in real time whether the received motor output pressure exceeds the set pressure threshold range during the fastening process.

Images