Photoelectric weft yarn breakage detection method and system of high-speed warp knitting machine

Abstract

The invention relates to the technical field of glass fiber production, in particular to a photoelectric type broken weft yarn detection method and system of a high-speed warp knitting machine. The method comprises the steps that a photoelectric switch is installed below a porcelain eye through which each weft yarn is drawn out of a yarn barrel and passes, and the detection face of the photoelectric switch is arranged opposite to the axis of the porcelain eye; when the yarn rotates around the axis of the porcelain eye, the photoelectric switch can generate a shading pulse signal; the shading pulse signals are collected and counted in real time; setting a detection period according to yarn operation characteristics, and when a preset number of shading pulse signals are not collected in the detection period, judging that the channel is in a broken yarn state; when the yarn breaking state is judged, yarn breaking information is sent to a main control system of the warp knitting machine, and the main control system gives an alarm and executes shutdown or processing. Compared with a traditional detection mode which only depends on the static shading state of the yarn, the photoelectric broken yarn detection method based on the dynamic motion characteristics of the yarn is introduced, and the accuracy and reliability of broken yarn recognition are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of glass fiber production, and particularly relates to a photoelectric weft yarn breakage detection method and system of a high-speed warp knitting machine. BACKGROUND

[0002] Glass fiber yarn has the characteristics of high hardness, large brittleness, rough surface, easy static electricity and burr, etc., which makes the yarn breakage problem more prominent in the high-speed warp knitting process compared with ordinary textile yarn. Once the yarn breakage is not handled in time, it will cause the warp beam to stop, the fabric to have defects, and even the whole cloth to be scrapped, causing significant material and time loss. Therefore, a reliable and efficient yarn breakage detection device is the core to ensure the production efficiency and product quality of glass fiber warp knitting.

[0003] In the prior art, a photoelectric sensor is usually used to detect whether the glass fiber yarn is blocked to determine whether there is yarn breakage. However, the glass fiber yarn breakage may occur in the warp knitting machine or other places, and the broken yarn stays in the original place, so that in the actual yarn breakage case, the photoelectric sensor can still detect the blocking state of the glass fiber yarn, and cannot timely detect the yarn breakage and alarm.

[0004] The information disclosed in this BACKGROUND section is only for the purpose of enhancing the understanding of the background of the present application and should not be taken as admitting that such information forms a prior art base for the present application. SUMMARY

[0005] The present application provides a photoelectric weft yarn breakage detection method and system of a high-speed warp knitting machine, thereby effectively solving the problems in the background art.

[0006] In order to achieve the above purpose, the technical solution adopted by the present application is as follows: a photoelectric weft yarn breakage detection method of a high-speed warp knitting machine, comprising the following steps: A photoelectric switch is installed below the porcelain eye through which each weft yarn is drawn out and passes, and the detection surface of the photoelectric switch is arranged opposite to the porcelain eye axis, so that when the yarn rotates around the porcelain eye axis, the photoelectric switch can generate a light blocking pulse signal; The light blocking pulse signal is collected and counted in real time; According to the yarn running characteristics, a detection period is set, and when a predetermined number of light blocking pulse signals are not collected within the detection period, it is judged that the channel is in a yarn breakage state; When it is judged that the yarn is broken, the yarn breakage information is sent to the warp knitting machine main control system, and the main control system issues an alarm and executes a stop or processing.

[0007] Further, the yarn generates two light blocking pulse signals corresponding to one rotation when the yarn rotates around the eye axis, and the two light blocking pulse signals are the basic unit for determining whether the yarn is moving.

[0008] Further, the detection period and the sampling frequency for collecting the light blocking pulse signals in real time are determined according to the diameter of the yarn tube, the weft laying speed, the weft laying angle, and the weft laying width.

[0009] Further, the detection period is calculated as follows: Calculate the maximum light blocking pulse period: Set n1 times of weft laying per minute, a weft laying angle of 90°, a weft laying width of a1, a weft laying door width A, and a maximum diameter D of the weft yarn tube. max ; The yarn length for each weft laying is mm: L1=(A+a1)*2; The yarn circle number for each weft laying at the maximum tube diameter is: Q1= L1 / (πD max )=2(A+a1) / (πD max ); The minimum light pulse frequency is: f1=2*Q1*n1 / 60=(A*n1+a1*n1) / (15πD max ); The maximum light pulse period is s: T1=1 / f1=15πD max / n1(A*n1+a1*n1); Set the detection period to be greater than T1 and less than 2T1.

[0010] Further, the sampling frequency is calculated as follows: Calculate the highest light blocking pulse frequency: Set n2 times of weft laying per minute, a weft laying angle of 45°, a weft laying width of a2, a weft laying door width A, and a minimum diameter D of the weft yarn tube. min ; The yarn length for each weft laying is mm: L2=(A* +a2)*2; The yarn circle number for each weft laying at the minimum tube diameter is: Q2= L2 / (πD min )=2( A+a2) / (πD min ); The highest light pulse frequency is: f2=2*Q2*n2 / 60=( A*n2+a2*n2) / (15πD min ); Minimum light pulse period, unit: s: T2=1 / f2=15πD min / ( A*n2+a2*n2); Set the sampling frequency greater than 10f2.

[0011] The application also includes an optical yarn breakage detection system for a high-speed warp knitting machine, which uses the method described above, and the system comprises: A plurality of photoelectric switches installed below each weft eye, a data acquisition device for receiving and collecting the photoelectric switch signals, and a master PLC in communication with the data acquisition device and controlling the operation of the warp knitting machine; The data acquisition device is used for real-time counting and analyzing the photoelectric switch pulse signals, and sends a yarn breakage alarm signal to the PLC when a predetermined number of pulses are not detected within a predetermined detection period; The PLC executes an alarm and stops the warp knitting machine or performs other predetermined processing after receiving the yarn breakage alarm signal.

[0012] Further, the system also includes a monitoring screen for monitoring and parameter setting, which displays the real-time state of each channel, the yarn breakage position and allows the operator to adjust the detection period, threshold and photoelectric switch related parameters.

[0013] Further, the master PLC sets the working mode of the data acquisition device and reads the yarn state of each channel in the data acquisition device in real time through the RS485 communication interface using the MODBUS-RTU protocol. Each data acquisition device is provided on a yarn rack tray, and each photoelectric switch is provided on each yarn in the yarn rack tray, each data acquisition device supports at least 16 photoelectric switch input channels, and a plurality of data acquisition devices are cascaded through an RS485 bus.

[0014] The application also includes a computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor executes the computer program to implement the method described above.

[0015] The application also includes a storage medium having a computer program stored thereon, wherein the computer program is executed by a processor to implement the method described above.

[0016] The beneficial effects of this invention are as follows: By introducing a photoelectric yarn breakage detection method based on the dynamic motion characteristics of yarn, compared with the traditional detection method that only relies on the static light-blocking state of the yarn, the accuracy and reliability of yarn breakage identification are significantly improved. Specifically, this embodiment utilizes the glass fiber weft yarn, due to its yarn storage method, which is pulled out from the inner diameter when it is pulled out of the yarn bobbin. During the warp knitting process, the rotational motion around the ceramic eye axis causes the photoelectric switch to periodically generate light-blocking pulse signals. By collecting and judging the number of light-blocking pulse signals within a set detection period in real time, it can truly reflect whether the yarn is in a continuous motion state. Even if the yarn breakage occurs downstream of the ceramic eye, and the broken yarn fragment remains in the original detection area and continues to block the light path, because it no longer generates regular rotational motion, the photoelectric switch cannot collect the light-blocking pulse signals that meet the preset number requirements, and the yarn breakage state can still be accurately determined, avoiding the missed detection problem that is common in the prior art. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of the method of the present invention; Figure 2 A schematic diagram showing the location of the photoelectric switch; Figure 3 This is a schematic diagram of the system structure of the present invention; Figure 4 This is a schematic diagram of the structure of the computer device of the present invention. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0020] like Figure 1 As shown: A photoelectric weft yarn breakage detection method for a high-speed warp knitting machine, comprising the following steps: A photoelectric switch is installed below the ceramic eye through which each weft yarn is drawn from the yarn bobbin. The detection surface of the photoelectric switch is arranged opposite to the axis of the ceramic eye. Figure 2 As shown, when the yarn rotates around the axis of the ceramic eye, the photoelectric switch can generate a light-blocking pulse signal. Real-time acquisition and counting of shading pulse signals; The detection cycle is set according to the yarn running characteristics. When the predetermined number of light-blocking pulse signals are not collected within the detection cycle, the channel is judged to be in a yarn breakage state. When a yarn breakage is detected, the yarn breakage information is sent to the warp knitting machine's main control system, which then issues an alarm and executes a shutdown or other processing.

[0021] By introducing a photoelectric yarn breakage detection method based on the dynamic motion characteristics of yarn, this method significantly improves the accuracy and reliability of yarn breakage identification compared to traditional detection methods that rely solely on the static light-blocking state of the yarn. Specifically, this embodiment utilizes the glass fiber weft yarn, which, due to its storage method, is pulled out from the inner diameter of the yarn bobbin. During warp knitting, its rotational motion around the ceramic eye axis causes the photoelectric switch to periodically generate light-blocking pulse signals. By real-time acquisition and judgment of the number of light-blocking pulse signals within a set detection period, it can accurately reflect whether the yarn is in a continuous motion state. Even if the yarn breakage occurs downstream of the ceramic eye, and the broken yarn fragment remains in the original detection area, continuously blocking the light path, the photoelectric switch cannot acquire the preset number of light-blocking pulse signals because it no longer generates regular rotational motion. This still accurately determines the yarn breakage state, avoiding the missed detection problem commonly found in existing technologies.

[0022] The detection method in this embodiment is highly compatible with the operating characteristics of high-speed warp knitting machines. The detection logic is unaffected by minor fluctuations in yarn color and diameter, or environmental dust, making it suitable for complex operating conditions involving high-speed operation and frequent yarn breaks in glass fiber yarns. This facilitates stable and continuous online monitoring. By promptly sending yarn breakage information to the warp knitting machine's main control system, alarms can be triggered and shutdowns or corresponding actions can be taken at the initial stage of a yarn breakage, effectively reducing the spread of fabric defects and lowering the risk of scrapping entire rolls of fabric. This significantly improves the yield and production efficiency of glass fiber warp knitting production. Furthermore, this solution has a simple structure, low modification costs, and is easy to promote and apply on existing warp knitting equipment, demonstrating good engineering practicality and industrial value.

[0023] In this embodiment, when the yarn rotates around the axis of the ceramic eye, two light-blocking pulse signals are generated for each rotation. The two light-blocking pulse signals are the basic unit for determining whether the yarn is moving.

[0024] By using the two light-blocking pulse signals generated after each complete rotation of the yarn around the ceramic eye axis as the basic unit for determining whether the yarn is in motion, the yarn breakage detection logic becomes clearer, more stable, and easier to implement. On one hand, compared to methods relying solely on a single light-blocking signal, using "two light-blocking pulses" as a complete judgment unit effectively filters out occasional light-blocking signals caused by jitter, momentary oscillations, or environmental interference, significantly reducing the probability of false judgments and false alarms, thereby improving the reliability of the detection results. On the other hand, this basic unit corresponds one-to-one with the actual rotational motion of the yarn, and the pulse signal has a clear physical meaning. This facilitates the calibration and matching of the detection cycle and pulse threshold according to the warp knitting machine's operating speed and the yarn's working condition, making the detection algorithm more engineering-controllable and adaptable.

[0025] The detection cycle and the sampling frequency for real-time acquisition of the shading pulse signal are determined based on the yarn bobbin diameter, weft laying speed, weft laying angle, and weft laying width.

[0026] By comprehensively considering the impact of the above parameters on yarn running speed and rotation frequency, the detection cycle can be matched with the characteristics of the shading pulses generated under normal yarn movement, avoiding misjudgments caused by an excessively short detection cycle or delayed yarn breakage response due to an excessively long detection cycle. Simultaneously, the sampling frequency is coordinated with the actual generation frequency of the shading pulses during yarn rotation, ensuring complete and accurate capture of the shading pulse signal and preventing pulse loss due to insufficient sampling. Therefore, yarn breakage detection maintains stable detection accuracy and response speed under different yarn bobbin specifications and weft laying conditions, further improving the system's adaptability to changing working conditions and overall detection reliability.

[0027] In this embodiment, the detection cycle is calculated as follows: Calculate the maximum shading pulse period: The weft layup is set to n1 times per minute, with a layup angle of 90°, a layup width of a1, a layup width of A, and a maximum diameter of the weft yarn bobbin D. max ; The length of yarn used for each weft layup, in mm: L1 = (A + a1) * 2; Number of weft loops per weft layup at maximum bobbin diameter: Q1 = L1 / (πD) max ) = 2(A + a1) / (πD) max ); Minimum optical pulse frequency: f1=2*Q1*n1 / 60=(A*n1+a1*n1) / (15πD max ); Maximum optical pulse period, in seconds: T1=1 / f1=15πDmax / n1(A*n1+a1*n1) Set the detection period to be greater than T1 and less than 2T1.

[0028] Based on the above calculations, this embodiment sets the yarn breakage detection cycle to a time interval greater than T1 and less than 2T1. This ensures that at least a complete basic unit of the shading pulse can be collected under normal operating conditions. Simultaneously, when yarn breaks, the shading pulse disappears, or its quantity significantly decreases, the yarn breakage determination can be completed within a reasonable timeframe, thus balancing detection accuracy and response speed. This method is suitable for stable yarn breakage detection under high-speed warp knitting conditions.

[0029] As a preferred embodiment of the above, the sampling frequency is calculated as follows: Calculate the highest shading pulse frequency: The weft layup rate is set to n² times per minute, the layup angle is 45°, the layup width is a², the layup width is A, and the minimum diameter of the weft yarn bobbin is D. min ; The length of yarn used for each weft layup, in mm: L2 = (A*) +a2)*2; Number of weft loops per weft layup at minimum bobbin diameter: Q2 = L2 / (πD) min ) = 2 ( A+a2) / (πD min ); Highest optical pulse frequency: f2=2*Q2*n2 / 60=( (A*n2+a2*n2) / (15πD) min ); Minimum optical pulse period, in seconds: T2=1 / f2=15πD min / ( A*n2+a2*n2); Set the sampling frequency to be greater than 10f2.

[0030] In this embodiment, the sampling frequency of the shading pulse signal is set to be greater than 10f2. This setting ensures a sufficient number of sampling points within each minimum shading pulse cycle, preventing missed pulse detection or waveform distortion due to insufficient sampling frequency. This improves the accuracy and stability of shading pulse counting, further guaranteeing the reliability of yarn breakage detection under high-speed warp knitting and complex operating conditions.

[0031] Based on the production site conditions, it was calculated that the minimum frequency of the light pulses that the photoelectric sensor needs to detect is 0.63Hz (period 1.59 seconds), and the maximum frequency is 12.4Hz (period 0.08 seconds).

[0032] Considering the variation in yarn (sheet) width (thickness), which leads to a change in optical pulse width (duty cycle), and through experimental verification, the basic technical parameters of the photoelectric switch are determined as follows: 1. Power supply voltage: DC24V; 2. Operating current: <20mA; 3. Response speed: <2ms, i.e., sampling frequency greater than 500Hz; To ensure timely and reliable identification of yarn breakage status at both the highest and lowest operating speeds (within a single weft laying period), the identification cycle is tentatively set at 2 seconds.

[0033] like Figure 3 As shown, this embodiment also includes a photoelectric weft yarn breakage detection system for a high-speed warp knitting machine, using the method described above. The system includes: Several photoelectric switches installed below each weft yarn eyelet, a data acquisition device for receiving and collecting photoelectric switch signals, and a main control PLC that communicates with the data acquisition device and controls the operation of the warp knitting machine; The data acquisition device is used to count and analyze the photoelectric switch pulse signals in real time. When a predetermined number of pulses are not detected within a predetermined detection cycle, a yarn breakage alarm signal is sent to the PLC. After receiving the yarn breakage alarm signal, the PLC will execute the alarm and stop the warp knitting machine or perform other predetermined actions.

[0034] This system is based on the aforementioned photoelectric weft yarn breakage detection method and is used to monitor the real-time operating status of each weft yarn during high-speed warp knitting. The system includes several photoelectric switches, a data acquisition device, and a main control PLC. The photoelectric switches are respectively installed below the corresponding eyelet of each weft yarn, generating a light-blocking pulse signal when the weft yarn rotates around the eyelet axis. The data acquisition device is electrically connected to each photoelectric switch and is used to receive, acquire, count, and analyze the light-blocking pulse signals in real time. The main control PLC is communicatively connected to the data acquisition device and is used to receive yarn breakage alarm signals and control the operating status of the warp knitting machine.

[0035] During system operation, the data acquisition device statistically analyzes the light-blocking pulse signals output by the photoelectric switches of each channel according to a preset detection cycle and pulse threshold. When no predetermined number of light-blocking pulse signals are detected within the detection cycle, it is determined that the corresponding weft yarn is in a yarn breakage state, and a yarn breakage alarm signal is sent to the main control PLC. Upon receiving the yarn breakage alarm signal, the main control PLC immediately executes the alarm prompt and performs shutdown or other corresponding processing operations on the warp knitting machine according to the preset control strategy.

[0036] The system also includes a monitoring screen for monitoring and parameter setting. The monitoring screen displays the real-time status of each channel, the location of yarn breakage, and allows operators to adjust the detection cycle, threshold, and photoelectric switch parameters.

[0037] The monitoring screen communicates with the data acquisition device and / or the main control PLC to visually monitor the system's operating status and set and adjust detection parameters. Through the monitoring screen, the operating status of each weft yarn detection channel, the status of the shading pulse signal, and yarn breakage alarm information can be displayed in real time. When a yarn breakage occurs, the specific location of the breakage is clearly indicated, facilitating quick fault location and handling by operators. Furthermore, the monitoring screen provides parameter setting functions, allowing operators to flexibly adjust and optimize the detection cycle, shading pulse judgment threshold, and related parameters of the photoelectric switch according to different yarn specifications, warp knitting speeds, and production conditions. These settings enable the yarn breakage detection system to maintain good detection accuracy and response speed under different operating conditions, further improving the system's adaptability and maintainability, while reducing the intensity of manual inspections and enhancing the automation level and operational reliability of the high-speed warp knitting production process.

[0038] As a preferred embodiment of the above, the main control PLC uses the RS485 communication interface and the MODBUS-RTU protocol to set the working mode of the data acquisition device and read the yarn status of each channel in the data acquisition device in real time. Each yarn rack tray is equipped with a data acquisition device. There are n data acquisition devices for yarn breakage, where n ranges from [8, 24]. Each yarn in the yarn rack tray is equipped with a photoelectric switch. Each yarn breakage data acquisition device is connected to m photoelectric switches, where m ranges from [10, 20]. Each data acquisition device supports at least 16 photoelectric switch input channels. Multiple data acquisition devices are cascaded via an RS485 bus.

[0039] In terms of system architecture, each yarn tray is equipped with an independent data acquisition device, and each weft yarn within the tray is associated with a photoelectric switch for individual detection of its operating status. Each data acquisition device supports at least 16 photoelectric switch input channels, enabling parallel detection of multiple weft yarns within the same yarn tray. Multiple data acquisition devices are cascaded via an RS485 bus and uniformly connected to the main control PLC, achieving modular expansion of the system.

[0040] Through the aforementioned communication and structural design, not only is the amount of on-site wiring reduced and the system's anti-interference capability improved, but the number of detection channels can also be flexibly expanded according to the scale of the warp knitting machine, making it suitable for the application needs of large-width, high-count, high-speed warp knitting machines. Simultaneously, the main control PLC can acquire the operating status and yarn breakage information of each yarn in real time and accurately, facilitating rapid response to yarn breakage anomalies and further improving the overall system stability and engineering practicality.

[0041] Please see Figure 4 The diagram shows a structural schematic of a computer device provided in an embodiment of this application. An embodiment of this application provides a computer device 400, including a processor 410 and a memory 420. The memory 420 stores a computer program executable by the processor 410. When the computer program is executed by the processor 410, it performs the method described above.

[0042] This application embodiment also provides a storage medium 430, on which a computer program is stored, and the computer program is executed by a processor 410 to perform the above method.

[0043] The storage medium 430 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), Programmable Red-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0044] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. "A plurality of" means two or more, unless otherwise explicitly specified.

[0045] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0046] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0047] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain.

[0048] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0049] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0050] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0051] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A photoelectric weft yarn breakage detection method for a high-speed warp knitting machine, characterized in that, Includes the following steps: A photoelectric switch is installed below the ceramic eye through which each weft yarn is drawn from the yarn bobbin. The detection surface of the photoelectric switch is arranged opposite to the axis of the ceramic eye, so that when the yarn rotates around the axis of the ceramic eye, the photoelectric switch can generate a light-blocking pulse signal. The light-blocking pulse signal is acquired and counted in real time; The detection cycle is set according to the yarn running characteristics. When the predetermined number of light-blocking pulse signals are not collected within the detection cycle, the channel is determined to be in a yarn breakage state. When a yarn breakage is detected, the yarn breakage information is sent to the warp knitting machine's main control system, which then issues an alarm and executes a shutdown or other processing.

2. The photoelectric weft yarn breakage detection method for a high-speed warp knitting machine according to claim 1, characterized in that, When the yarn rotates around the axis of the ceramic eye, two light-blocking pulse signals are generated for each rotation. These two light-blocking pulse signals are the basic unit for determining whether the yarn is in motion.

3. The photoelectric weft yarn breakage detection method for a high-speed warp knitting machine according to claim 1 or 2, characterized in that, The detection cycle and the sampling frequency for real-time acquisition of the shading pulse signal are determined based on the yarn bobbin diameter, weft laying speed, weft laying angle, and weft laying width.

4. The photoelectric weft yarn breakage detection method for a high-speed warp knitting machine according to claim 3, characterized in that, The detection cycle is calculated as follows: Calculate the maximum shading pulse period: The weft layup is set to n1 times per minute, with a layup angle of 90°, a layup width of a1, a layup width of A, and a maximum diameter of the weft yarn bobbin D. max ; The length of yarn used for each weft layup, in mm: L1 = (A + a1) * 2; Number of weft loops per weft layup at maximum bobbin diameter: Q1= L1 / (πD max )=2(A+a1) / (πD max ); Minimum optical pulse frequency: f1=2*Q1*n1 / 60=(A*n1+a1*n1) / (15πD max ); Maximum optical pulse period, in seconds: T1=1 / f1=15πD max / n1(A*n1+a1*n1); The detection period is set to be greater than T1 and less than 2T1.

5. The photoelectric weft yarn breakage detection method for a high-speed warp knitting machine according to claim 3, characterized in that, The sampling frequency is calculated as follows: Calculate the highest shading pulse frequency: The weft layup rate is set to n² times per minute, the layup angle is 45°, the layup width is a², the layup width is A, and the minimum diameter of the weft yarn bobbin is D. min ; The length of yarn used for each weft layup, in mm: L2=(A* +a2)*2; Number of weft loops per weft layup at minimum bobbin diameter: Q2 = L2 / (πD min )=2( A+a2) / (πD min (); Highest optical pulse frequency: f2 = 2 * Q2 * n2 / 60 = ( A*n2+a2*n2) / (15πD min (); Minimum optical pulse period, in seconds: T2=1 / f2=15πD min / ( A*n2+a2*n2) ; The sampling frequency is set to be greater than 10f2.

6. A photoelectric weft yarn breakage detection system for a high-speed warp knitting machine, characterized in that, Using the method as described in any one of claims 1 to 5, the system comprises: Several photoelectric switches installed below each weft yarn eyelet, a data acquisition device for receiving and acquiring the signals from the photoelectric switches, and a main control PLC that communicates with the data acquisition device and controls the operation of the warp knitting machine; The data acquisition device is used to count and analyze the photoelectric switch pulse signals in real time. When a predetermined number of pulses are not detected within a predetermined detection cycle, a yarn breakage alarm signal is sent to the PLC. After receiving the yarn breakage alarm signal, the PLC will trigger an alarm and stop the warp knitting machine or perform other predetermined actions.

7. The photoelectric weft yarn breakage detection system for a high-speed warp knitting machine according to claim 6, characterized in that, The system also includes a monitoring screen for monitoring and parameter setting. The monitoring screen displays the real-time status of each channel, the location of yarn breakage, and allows operators to adjust the detection cycle, threshold, and photoelectric switch related parameters.

8. The photoelectric weft yarn breakage detection system for a high-speed warp knitting machine according to claim 6, characterized in that, The main control PLC uses the RS485 communication interface and the MODBUS-RTU protocol to set the working mode of the data acquisition device and read the yarn status of each channel in the data acquisition device in real time. Each yarn tray is equipped with one of the aforementioned data acquisition devices, and each yarn in the yarn tray is equipped with one of the aforementioned photoelectric switches. Each data acquisition device supports at least 16 photoelectric switch input channels, and multiple data acquisition devices are cascaded via an RS485 bus.

9. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method as described in any one of claims 1-5.

10. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method as described in any one of claims 1-5.

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