A broken thread detection system and method for a webbing machine for producing ton bag straps

Abstract

The application provides a broken line detection system and method for a ribbon machine for ton bag sling production, and belongs to the technical field of automatic detection of textile machinery. The system comprises an overall pneumatic pressure difference detection unit, a partitioned electrostatic induction positioning unit, a control unit, a self-adaptive configuration unit and an external actuating mechanism. Meanwhile, the application also discloses a broken line detection method for the system. The application specifically provides a broken line detection system and method for a ribbon machine for ton bag sling production, which detects the broken line of the sling ribbon by cooperation of pneumatic pressure difference and electrostatic induction.

Description

Technical Field

[0001] This invention belongs to the field of automated testing technology for textile machinery, specifically referring to a broken thread detection system and method for a webbing machine used in the production of ton bag straps. Background Technology

[0002] As a key load-bearing component of FIBCs (Flexible Intermediate Bulk Containers), the lifting straps of FIBCs are woven from multiple warp yarns on a weaving machine. The number of warp yarns varies from 80 to 300 depending on the strap specifications. During the weaving process, warp yarn breakage is a frequent failure, seriously affecting production efficiency and product quality.

[0003] Existing yarn breakage detection solutions have significant limitations: mechanical overlap detection relies on the contact between a metal probe and the yarn, which easily wears down the yarn, causes mechanical parts to jam, and cannot accurately locate the breakage; photoelectric sensor detection requires sensors that match the number of warp yarns, resulting in high hardware costs, complex wiring, and lenses that are easily contaminated by dust, making maintenance cumbersome. When detecting PP / PE plastic flat yarn warp yarns, the detection accuracy is further reduced by the reflection and static electricity of the plastic flat yarns; machine vision detection equipment requires large investments, has complex algorithms, and its optical components are easily affected by dust. It is also difficult to quickly adapt to different widths and warp densities, limiting its application in flexible production. Summary of the Invention

[0004] In view of the above situation and to overcome the defects of the prior art, the purpose of the present invention is to provide a thread breakage detection system and method for weaving machines used in the production of ton bag straps, so as to at least partially solve the problems mentioned in the background art.

[0005] The technical solution adopted by this invention is as follows: This invention proposes a thread breakage detection system for a webbing machine used in the production of ton bag straps, comprising: The overall pneumatic pressure difference detection unit is a pneumatic detection unit that detects the overall resistance of warp yarns based on the principle of pneumatic pressure difference. It is used to continuously and in real time monitor the status of full-width warp yarns, and also has an online cleaning function for the surface of warp yarns, making it suitable for dusty environments in textile workshops. The zone electrostatic induction positioning unit is an electrostatic induction positioning unit that detects the electrostatic signal of the warp yarn in each zone based on the principle of electrostatic induction. It is used to accurately locate the specific area where the breakage occurred after the overall pneumatic pressure difference detection unit triggers the breakage signal. It is adapted to the inherent characteristics of static electricity generated by friction when PP / PE plastic flat yarn is fed, and no additional static electricity generation device is required. The control unit is electrically connected to the overall pneumatic differential pressure detection unit and the partition electrostatic induction positioning unit, and is used to receive signals, control the start and stop of the partition electrostatic induction positioning unit, and output alarm and shutdown signals. An adaptive configuration unit, electrically connected to and integrated within the control unit, is used to enable the system to adapt to the production needs of webbing with different warp yarn counts and simplify the operation process. An external actuator, electrically connected to the control unit, is used to perform corresponding actions in response to commands output by the control unit, thereby improving fault handling efficiency.

[0006] Furthermore, the overall pneumatic differential pressure detection unit is installed at the warp guide frame behind the weaving machine, and includes an air source module, an air jet head, a pressure tap, and a differential pressure sensor. The air source module is connected to the air jet head to provide continuous airflow to the air jet head. The air jet head and the pressure tap are arranged opposite each other on both sides of the warp array along the width direction of the weaving, and the air jet head sprays airflow along the width direction of the weaving to pass laterally through the warp array. The differential pressure sensor is connected to the pressure tap through a hose to detect the air pressure value at the pressure tap, which reflects the overall resistance of the warp yarns across the entire width to the airflow.

[0007] Furthermore, the air source module includes an air compressor, a filter, and a pressure regulating valve. The air outlet of the air compressor is sealed to the air inlet of the filter through a pressure-resistant air pipe. The air outlet of the filter is connected to the air inlet of the pressure regulating valve. The air outlet of the pressure regulating valve is connected to the air inlet of the jet head.

[0008] Furthermore, the jet head is a long, flat nozzle with its jet direction directly opposite the warp yarns of the width array, and the pressure tap has its opening direction vertically downward and is equipped with a dust cap.

[0009] Furthermore, the partitioned electrostatic induction positioning unit includes multiple metal induction electrodes, a high-impedance amplifier, and a signal conditioning circuit. The multiple metal induction electrodes are arranged at equal intervals along the width of the webbing on an insulating mounting bracket. The mounting bracket is equipped with a scale and a lockable slider. Each electrode is detachably mounted on a slider, and the number of metal induction electrodes depends on the width of the webbing. The high-impedance amplifier is connected to each metal induction electrode and is used to amplify the electrostatic signal generated by the friction of the warp yarns with high fidelity. The signal conditioning circuit includes a bandpass filter and an RMS conversion module, used to filter out power frequency interference and mechanical vibration noise, and to convert the sensed electrostatic AC signal into a DC voltage characteristic value representing its intensity for comparison and judgment by the control unit.

[0010] Furthermore, the length of the metal sensing electrode is matched with the width of the warp yarns covered by the electrode.

[0011] Furthermore, the insulating mounting bracket has a dovetail groove along its width direction, and the slider slides into the dovetail groove. A continuous grounding busbar is embedded inside the dovetail groove along its width direction, and the grounding busbar is electrically connected to the system common ground. The lower end of the metal induction electrode has an insulating base, which is detachably connected to the slider. Two metal shielding plates are provided on both sides of the insulating base. The metal shielding plates and the metal induction electrode are isolated by the solid wall of the insulating base to achieve electrical isolation. The bottom of the metal shielding plate has an elastic grounding contact. When the slider moves the metal induction electrode to be installed on the insulating mounting bracket, the elastic grounding contact is pressed against the grounding busbar to form an electrical connection.

[0012] Furthermore, the control unit is configured as follows: Under normal conditions, only the overall pneumatic differential pressure detection unit is operational, while the zone electrostatic induction positioning unit is in a power-off standby state. When the differential pressure sensor detects that the air pressure value P is lower than the set threshold T1, the control unit determines that a break has occurred, immediately generates a first-level alarm signal, and activates the zone electrostatic induction positioning unit to achieve rapid positioning and avoid the continuous breakage of multiple warp yarns. After the partitioned electrostatic induction positioning unit is powered on, it collects the electrostatic signals V of each electrode. current(i) Compare it with its corresponding electrostatic baseline threshold T 2(i) Compare the signals and determine the bandwidth range where the line break occurs based on changes in signal strength. The control unit outputs information about the broken area and issues a stop signal to prevent the broken yarn from continuing to get tangled, causing equipment damage or product quality defects.

[0013] Furthermore, the adaptive configuration unit is integrated with the control unit, and the adaptive configuration unit includes: The baseline learning module is used to automatically acquire differential pressure sensor readings during system startup or manual calibration, and calculate the average value as the dynamic baseline P. baseline The disconnection threshold T1 is set to the dynamic baseline P. baseline Multiply by a preset scaling factor; The electrode configuration module is used to automatically calculate and prompt the electrode installation position and quantity based on the input total number of warp yarns and positioning accuracy, and to store electrode grouping information; The electrostatic threshold learning module is used to automatically learn the signal amplitude of each electrode under normal weaving conditions and establish an electrostatic baseline V. baseline（i） And set the disconnection threshold T for each area. 2(i) Set as electrostatic baseline V baseline（i） Multiply by a preset scaling factor; The one-click calibration module is used to trigger the automatic configuration of all parameters and threshold calculation with a single click, simplifying the operation process.

[0014] Furthermore, the external actuator includes, but is not limited to, one or more of the following: Audible and visual alarm: Used to issue an audible and visual alarm signal when the control unit determines that a wire breakage has occurred. It is installed above the control panel of the ribbon weaving machine or in a prominent position in the workshop to remind the operator to deal with it in time. Weaving machine stop controller: Used to receive stop commands from the control unit, control the main motor or clutch of the weaving machine to achieve rapid stop and prevent broken yarn from continuing to get tangled, causing equipment damage or product quality defects; Human-machine interface (display screen): Installed on the control panel of the ribbon weaving machine, it is used to display the differential pressure sensor reading, the electrostatic signal value of each electrode, the time of the breakage and the specific interval number in real time, so that the operator can quickly locate the fault and repair it; it also integrates a one-key calibration button and a manual reset button, which allow the operator to trigger the initialization learning process and clear the alarm status.

[0015] Through the above settings, the external actuator and control unit work together to achieve real-time response and visualization of the wire breakage detection results, further improving the level of production automation and fault handling efficiency.

[0016] The present invention also provides a method for detecting thread breakage on a webbing machine for producing FIBC (Flexible Intermediate Bulk Container) straps, which is implemented using the above-mentioned system and includes an initialization and adaptive learning stage and a real-time monitoring and thread breakage handling stage.

[0017] Furthermore, the initialization and adaptive learning phase includes: (1) Differential pressure baseline learning: The control unit controls the pneumatic unit to work, collects the air pressure values ​​of the differential pressure sensor in multiple cycles under normal weaving conditions, and calculates the average value as the dynamic baseline P. baseline And set the disconnection detection threshold T1 to P baseline Multiply by a preset scaling factor; (2) Electrostatic baseline learning: The control unit briefly activates the electrostatic induction unit to collect the characteristic values ​​of each electrode signal and record them as the electrostatic signal baseline V of each area. baseline（i） And set the disconnection threshold T for each area. 2(i) Set to V baseline（i） Multiply by a preset scaling factor.

[0018] (3) Parameter storage: Store T1, T 2(i) Electrode partitioning configuration information is stored in non-volatile memory; (4) One-click calibration: The above initialization learning process is encapsulated and triggered by an external physical button or touch screen button. The system automatically executes the entire learning process without the need for manual intervention in parameter settings.

[0019] Furthermore, the real-time monitoring and disconnection handling stage specifically includes the following steps: a) At the warp guide frame behind the weaving machine, a uniform transverse airflow is sprayed from one side of the warp array to the other side along the width direction through an air jet head; b) On the other side of the warp array, the air pressure value P corresponding to the overall resistance of the full-width warp to the airflow is detected in real time through the pressure tap. Under normal conditions, only the pneumatic unit works, and the control unit continuously compares the air pressure value P with the threshold T1. c) When the detected air pressure value P is lower than the preset disconnection judgment threshold T1, a disconnection is determined to have occurred, and a first-level alarm signal is immediately generated. d) In response to the disconnection detection, the control unit immediately supplies power to the electrostatic induction positioning unit, activates the zoned electrostatic induction positioning unit, and collects the electrostatic induction signals V from multiple electrodes arranged along the width direction. current(i) ; e) Convert the electrostatic induction signal V of each electrode current(i) and their respective electrostatic baseline thresholds T 2(i) The signal strength is compared to determine the amplitude range where the line break occurs; the location logic is as follows: if only one electrode's signal V... current(i) Below T 2(i) If the signal of multiple adjacent electrodes is lower than T, then the interval corresponding to that electrode is directly located; 2(i) If so, it can be determined that the break occurred at the boundary between the two zones, or that multiple warp yarns are broken; f) Output the results containing information about the broken thread area and control the weaving machine to stop; g) The control unit simultaneously drives the audible and visual alarm to emit audible and visual alarm signals and displays the disconnection area information on the human-machine interface; h) After the operator completes the disconnection repair, input a reset signal through the human-machine interface or external reset button. The control unit responds to the reset signal, shuts off the power of the electrostatic induction unit, clears the alarm status, and the system returns to step a) to continue normal monitoring.

[0020] The technical solution provided by this invention has the following beneficial effects: (1) By combining pneumatic differential pressure full-width detection with electrostatic induction positioning to accurately lock the broken area, the comprehensiveness of the broken area detection is guaranteed and the broken area is quickly located. Furthermore, both detection methods are non-contact signal acquisition methods, which do not require direct contact with the warp yarn, effectively avoiding the wear of the yarn caused by existing mechanical contact detection.

[0021] (2) The overall pneumatic differential pressure detection unit realizes the dual-use design of detection and cleaning in one air, breaking the conventional mode of separating detection and cleaning functions. The airflow generated by this unit is not only used to pass through the warp array laterally and judge whether a break has occurred by the change of air pressure, but also to blow the warp surface in real time to remove attached dust, lint and other impurities.

[0022] (3) The design of the zoned electrostatic induction positioning unit fully matches the production characteristics of the plastic webbing of the ton bag. It accurately utilizes the inherent characteristics of static electricity generated by the friction between the plastic warp yarn and the air and the yarn guide during the warp feeding process, without the need to add an additional static electricity generating device, thus achieving accurate positioning of the broken area. Attached Figure Description

[0023] Figure 1 This is a structural block diagram of a thread breakage detection system and method for a webbing machine used in the production of ton bag straps, as proposed in an embodiment of the present invention. Figure 2 This is a flowchart illustrating a thread breakage detection system and method for a webbing machine used in the production of ton bag straps, as proposed in an embodiment of the present invention. Figure 3 This is a schematic diagram of the installation position of a thread breakage detection system and method for a webbing machine used in the production of ton bag straps, as proposed in an embodiment of the present invention. Figure 4 This is a schematic diagram of the metal induction electrode, insulating base, and installation position in a top view of a webbing machine breakage detection system and method for producing ton bag straps, as proposed in an embodiment of the present invention.

[0024] 1. Overall pneumatic differential pressure detection unit; 2. Zoned electrostatic induction positioning unit; 3. Control unit; 4. Adaptive configuration unit; 5. External actuator; 6. Weaving machine; 7. Warp yarn; 101. Air source module; 102. Air jet head; 103. Pressure tap; 104. Differential pressure sensor; 201. Metal induction electrode; 202. Insulated mounting bracket; 203. Slider; 204. Dovetail groove; 205. Insulated base; 206. Metal shielding sheet.

[0025] The accompanying drawings are provided to further understand the embodiments and form part of the specification. They are used together with the embodiments for explanation and do not constitute a limitation on the embodiments. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection.

[0027] In the description of the embodiments, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the embodiments 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. Therefore, they should not be construed as limitations on the embodiments.

[0028] Example 1 See Figure 1 , Figure 3 and Figure 4 The present invention provides a thread breakage detection system for a webbing machine used in the production of ton bag straps, comprising an overall pneumatic pressure difference detection unit 1, a zoned electrostatic induction positioning unit 2, a control unit 3, an adaptive configuration unit 4, and an external actuator 5.

[0029] 1. Overall pneumatic pressure difference detection unit: A pneumatic detection unit that detects the overall resistance of the warp yarn based on the principle of pneumatic pressure difference.

[0030] The overall pneumatic differential pressure detection unit 1 is installed at the warp yarn 7 guide frame behind the weaving machine 6. It is used for continuous and real-time status monitoring of the full-width warp yarn 7, and also has an online cleaning function for the surface of the warp yarn 7. The unit includes an air source module 101, an air jet head 102, a pressure tap 103, and a differential pressure sensor 104.

[0031] The air source module 101 includes an air compressor, a filter, and a pressure regulating valve. Specifically, the air compressor's outlet is sealed to the filter's inlet via a pressure-resistant air pipe. The filter's outlet is connected to the pressure regulating valve's inlet, and the pressure regulating valve's outlet is connected to the jet head 102's inlet. During operation, the air compressor generates compressed air. This compressed air enters the filter, where it removes oil mist, moisture, and fine dust particles to prevent contamination of the subsequent pressure tap 103 or differential pressure sensor 104. The cleaned compressed air then enters the pressure regulating valve, which adjusts its pressure to a preset value and maintains a constant output pressure even when the air source fluctuates or the flow rate changes. Finally, a constant-pressure, clean, continuous airflow is ejected from the jet head 102.

[0032] The jet nozzle 102 and the pressure tap 103 are positioned opposite each other on both sides of the warp yarn array 7 along the width of the webbing. The jet nozzle 102 is a long, flat nozzle that jets airflow along the width of the webbing to pass laterally through the warp yarn array 7. The pressure tap 103 is a copper tube with an inner diameter of 3 mm, located on the right side of the warp yarn array 7, opposite the jet nozzle 102. The opening of the pressure tap 103 is designed to face vertically downwards, and a dust cover is installed above it. The center trajectory line of the airflow from the jet nozzle 102 is located approximately 5 mm directly below the opening. This arrangement ensures that the lateral airflow passes horizontally directly below the opening of the pressure tap 103, rather than being blown directly into the pressure tap 103. The airflow blown out by the jet head 102 carries the flying fluff and sweeps horizontally below the pressure tap 103. Since the airflow direction is perpendicular to the opening direction of the pressure tap 103, and the flying fluff tends to sink downwards under the action of gravity, the flying fluff is difficult to enter the interior of the pressure tap 103 upwards, thus achieving self-cleaning and ensuring the stability of long-term operation.

[0033] The airflow ejected from the jet nozzle 102 can, on the one hand, clean the lint, dust and other impurities attached to the surface of the warp yarn 7 in real time, reducing problems such as electrostatic detection interference or increased yarn running resistance caused by dust accumulation; on the other hand, the airflow, together with the pressure tap 103, forms a pneumatic detection circuit.

[0034] The differential pressure sensor 104 is connected to the pressure tap 103 via a hose and is used to detect the air pressure value at the pressure tap 103.

[0035] Pneumatic differential pressure detection principle: When the stable airflow generated by the jet head 102 passes laterally through the dense array of warp yarns 7, it is hindered by the combined resistance of multiple warp yarns 7, forming a stable back pressure (i.e., higher static pressure) at the pressure tap 103. When any warp yarn 7 breaks, an additional airflow channel is formed at that point, reducing the overall resistance of the airflow through the entire yarn array. According to fluid dynamics principles, this will cause a significant drop in the static pressure value at the pressure tap 103. The differential pressure sensor 104 continuously monitors this static pressure value and determines whether a yarn breakage has occurred by comparing it with a set threshold.

[0036] Those skilled in the art will understand that the downward-facing opening of the pressure tap 103 and the airflow passing beneath it do not affect its accurate measurement of air pressure. This is because the differential pressure sensor 104 detects the static pressure at that location. According to the principle of wall static pressure transmission in fluid mechanics, when the lateral airflow passes directly below the pressure tap 103, although the airflow itself does not enter the pressure tap 103, a small stagnation zone is formed at the opening of the pressure tap 103. The static pressure in this zone can effectively enter the internal cavity of the pressure tap 103 through the opening and be transmitted to the differential pressure sensor 104 along the hose.

[0037] When the warp yarns 7 are intact, the airflow encounters significant resistance as it passes through the dense yarn array, resulting in a stable back pressure at the pressure tap 103. When any warp yarn 7 breaks, an additional airflow channel is created at the break point, reducing the overall resistance of the airflow through the entire yarn array, and the back pressure decreases significantly. The differential pressure sensor 104 monitors this static pressure value in real time and transmits the data to the control unit 3.

[0038] Through the above configuration, the overall pneumatic differential pressure detection unit 1 integrates online cleaning of the warp yarn 7 surface and real-time breakage detection of the full-width warp yarn 7, providing dual-purpose airflow, simplifying the system structure and improving detection reliability. Compared to existing devices with single detection functions, this unit does not require additional cleaning components, simplifying the system structure and reducing the interference of dust on detection accuracy.

[0039] II. Zoned Electrostatic Induction Positioning Unit 2: An electrostatic induction positioning unit that detects the electrostatic signals of the warp yarns in each zone based on the principle of electrostatic induction.

[0040] The zoned electrostatic induction positioning unit 2 is installed in front of or behind the warp yarn array 7 to accurately locate the breakage point after a breakage occurs. This unit includes multiple metal induction electrodes 201, a high-impedance amplifier, and signal conditioning circuitry.

[0041] Multiple metal sensing electrodes 201 are arranged at equal intervals along the width of the webbing on an insulating mounting bracket 202. The insulating mounting bracket 202 is made of aluminum alloy profile and extends along the width of the webbing. A high-impedance amplifier is connected to each metal sensing electrode 201 to amplify the weak electrostatic signal generated by the friction of the warp yarn 7 with high fidelity.

[0042] The signal conditioning circuit includes a bandpass filter and an RMS conversion module. The bandpass filter is used to filter out 50Hz power frequency interference and low-frequency mechanical vibration noise; the RMS conversion module converts the induced electrostatic AC signal into a DC voltage characteristic value that characterizes its intensity, which is then compared and judged by the control unit 3.

[0043] Specifically, the number of metal sensing electrodes 201 installed depends on the width of the webbing. Based on the total number of warp yarns 7 N currently produced (the total number of yarns determines the width of the webbing) and the preset positioning accuracy (e.g., each electrode covers M warp yarns 7), the required number of electrodes K (K≈N / M) can be calculated. The K electrodes are then adjusted and fixed on the bracket at equal intervals to ensure that the width interval corresponding to each electrode covers approximately the same number of warp yarns 7. When N is not divisible by M, the remaining warp yarns 7 are evenly distributed to the coverage intervals of the adjacent electrodes at both ends to ensure that there are no positioning blind spots for the warp yarns 7 across the entire width. If the number of remaining warp yarns 7 is ≤M / 2, they can be incorporated into one adjacent interval. If they are >M / 2, an additional electrode is added to cover the area, thus completing the closed loop of the calculation logic. This design allows the system hardware to flexibly adapt to products with different widths and warp yarn densities. Zoned monitoring can be achieved through physical adjustments without the need for complex circuit reconstruction.

[0044] The length of the metal sensing electrode 201 is matched to the width of the warp yarn 7 it covers: specifically, the length L of each electrode is... i Set to the corresponding warp 7 coverage width W i They are basically equal, that is, L i =W i ±δ, where δ is the allowable installation tolerance (e.g., ≤5mm). The principle behind this setting is that the electrostatic induction signal strength is positively correlated with the effective area of ​​the electrode facing the warp 7. When the electrode length is consistent with the coverage width, the electrode can uniformly sense the electrostatic signal of all warp 7 within its corresponding interval, avoiding signal attenuation or crosstalk between adjacent intervals due to edge effects.

[0045] To achieve electrode length adaptation under different warp yarn counts (N) and different coverage accuracy (M), this system is equipped with multiple sets of replaceable electrodes of different lengths. The appropriate electrode length is selected for installation based on the calculated coverage width.

[0046] As a specific embodiment, when production requires 150 warp yarns 7, with a spacing of 5mm between individual warp yarns 7, and each electrode is set to cover 15 warp yarns 7, the coverage width corresponding to a single metal induction electrode 201 is 75mm. The operator configures it according to the following steps: Based on a coverage width of 75mm, select a 70mm long metal induction electrode 201; calculate the required number of electrodes: K = 150 ÷ ​​15 = 10; install the 10 metal induction electrodes 201 onto the dovetail grooves 204 of the insulating mounting bracket 202 via their respective sliders 203; adjust the position of each slider 203 according to the scale to make the center distance between each metal induction electrode 201 75mm; tighten the set screws on each slider 203 to lock them. After installation, each metal induction electrode 201 faces approximately 15 warp yarns 7 (75mm wide), and the metal shielding plates 206 on both sides are located between adjacent electrodes and connected to the grounding busbar through elastic grounding contacts to form a complete electrostatic shielding barrier.

[0047] In this embodiment, a dovetail groove 204 is formed on the upper surface of the insulating mounting bracket 202 along the length direction, and a scale is provided on one side of the insulating mounting bracket 202 to indicate the installation position of each metal induction electrode 201; a continuous grounding bus is embedded in the inside of the dovetail groove 204 along the length direction, and one end of the grounding bus is connected to the common ground (GND) of the system through a conductor to ensure that the entire bus is at ground potential.

[0048] The metal sensing electrode 201 is made of copper, and an insulating base 205 is provided at its lower end. The insulating base 205 has a U-shaped structure and is injection molded from ABS engineering plastic. The metal sensing electrode 201 is fixed to the upper surface of the insulating base 205, and its upper surface is flush with the upper surface of the insulating base 205. The bottom of the insulating base 205 is detachably connected to the slider 203 by screws. The slider 203 is made of POM plastic, and its bottom is provided with a dovetail guide rail, which slides in cooperation with the dovetail groove 204 on the insulating mounting bracket 202. The slider 203 is provided with a set screw, which, when tightened, can lock the slider 203 and the metal sensing electrode 201 connected to it at any position on the insulating mounting bracket 202.

[0049] Each side of the insulating base 205 is provided with a metal shielding plate 206, which is made of 304 stainless steel. The metal shielding plate 206 is fixedly installed on both sides of the insulating base 205. The metal induction electrode 201 and the metal shielding plate 206 are isolated by the solid wall of the insulating base 205 to ensure electrical isolation between them and prevent the electrode signal from being short-circuited to ground by the shielding plate. The bottom of the metal shielding plate 206 is provided with a flexible grounding contact. The flexible grounding contact is made of beryllium copper spring sheet, welded and fixed to the bottom of the metal shielding plate 206, and extends out of the lower surface of the insulating base 205. When the slider 203 drives the metal induction electrode 201 to be installed on the insulating mounting bracket 202, the flexible grounding contact is compressed, forming a reliable crimped electrical contact with the grounding busbar in the dovetail groove 204.

[0050] The above electrical structure design can effectively shield electromagnetic interference in the workshop, prevent electrostatic induction signals from being distorted by external noise, ensure the anti-interference capability and signal acquisition accuracy of electrostatic induction positioning, and further adapt to the complex industrial environment of ton bag production.

[0051] Electrostatic induction positioning principle: During movement, the PP / PE plastic flat warp yarn 7 generates static electricity through friction with the air and the yarn guide. Because PP / PE is a highly insulating material, charge is difficult to conduct, and the static signal easily accumulates and remains stably on the yarn surface. When the warp yarn 7 is intact, the corresponding metal induction electrode 201 senses the electrostatic potential of the warp yarn 7 in that area through capacitive coupling, outputting a relatively high voltage signal. When a break occurs in a certain area, the warp yarn 7 in that area disappears, the static signal source is removed, and the induction signal of the corresponding electrode drops sharply. By comparing the signal strengths of each electrode, the specific area where the break occurred can be determined.

[0052] Signal characteristics: The electrostatic signal amplitude is stable in the normal warp yarn area 7; the signal amplitude drops sharply in the broken yarn area; the signal in adjacent areas remains basically unchanged. Combining the electrostatic characteristics of PP / PE plastic flat yarn, this electrostatic induction positioning solution requires no additional device to accurately capture a single broken yarn, demonstrating significantly better adaptability and practicality than existing detection solutions.

[0053] Actual measurements show that in a typical workshop environment with a relative humidity of 40%-60%, when the plastic flat yarn warp 7 of the webbing is running at a speed of 50m / min, a stable AC electrostatic signal of 1.5V±0.3V (peak value) can be generated on the copper induction electrode 10mm away from it, with a signal-to-noise ratio greater than 20dB, which fully meets the testing requirements.

[0054] Existing mechanical positioning components are prone to wear on the warp yarns 7, affecting the quality of the sling; while this solution uses electrostatic induction positioning, which does not require contact with the warp yarns 7, thus not damaging the yarns and achieving high-precision zone positioning.

[0055] III. Control Unit 3 The control unit 3, based on a microcontroller, is electrically connected to both the overall pneumatic differential pressure detection unit 1 and the zoned electrostatic induction positioning unit 2. Its configuration is as follows: Under normal conditions, only the overall pneumatic differential pressure detection unit 1 is in operation, while the zone electrostatic induction positioning unit 2 is in a power-off standby state to achieve low power consumption operation. When the differential pressure sensor 104 detects that the air pressure value P is lower than the set threshold T1, the control unit 3 determines that a disconnection has occurred, immediately generates a first-level alarm signal, and supplies power to the electrostatic induction positioning unit to wake it up from the standby state. After the partitioned electrostatic induction positioning unit 2 is powered on, the control unit 3 collects the DC voltage value V of each electrode after conditioning. current(i) and compare it with the pre-stored threshold T for each interval.2(i) Compare the signals and determine the bandwidth range where the line break occurs based on changes in signal strength. Control unit 3 outputs information about the disconnected area and issues a stop signal.

[0056] IV. Adaptive Configuration Unit 4 The adaptive configuration unit 4 is electrically connected to the control unit 3 to enable the system to adapt to the production requirements of webbing with different warp counts of 7 threads; the adaptive configuration unit 4 includes: The baseline learning module is used to automatically acquire readings from the differential pressure sensor 104 during system startup or manual calibration, and calculate the average value as the dynamic baseline P. baseline The disconnection threshold T1 is set to the dynamic baseline P. baseline Multiply by a preset proportional coefficient; the preset proportional coefficient is 70%-85%. The basis for setting this proportional coefficient is to ensure that air pressure fluctuations (such as those caused by slight fluctuations in ambient temperature or air source) under normal weaving conditions will not trigger the alarm falsely, while ensuring that the air pressure drop caused by the breakage of any warp yarn 7 (usually 15%-30% of the baseline) can be reliably identified; if the value is too low (such as below 70%), it may lead to missed detection of broken yarns, and if the value is too high (such as above 85%), it may lead to false alarms due to normal fluctuations. Experimental verification shows that the range of 70%-85% can balance detection sensitivity and anti-interference ability.

[0057] The electrode configuration module is used to automatically calculate and prompt the electrode installation position and quantity based on the input total number of warp yarns and positioning accuracy, and to store electrode grouping information; The electrostatic threshold learning module is used to automatically learn the signal amplitude of each electrode under normal weaving conditions and establish an electrostatic baseline V. baseline（i） And set the disconnection threshold T for each area. 2(i) Set as electrostatic baseline V baseline（i） Multiply by a preset scaling factor, which is 40%-60%. The scaling factor is set based on the following: During normal weaving, the amplitude of the electrostatic signal generated by the friction of the warp yarn 7 is relatively stable; when a break occurs, the warp yarn 7 in that area disappears, the electrostatic signal source is removed, and the signal amplitude usually drops sharply to below 30% of the baseline; setting the threshold in the range of 40%-60% can ensure that the signal drop after a break is reliably identified, and can also avoid misjudgment caused by normal signal fluctuations due to changes in environmental humidity, batch differences in yarn material, etc. The one-click calibration module is used to trigger the automatic configuration of all parameters and threshold calculation with a single click, simplifying the operation process.

[0058] V. External Implementing Agencies 5 External actuator 5 is electrically connected to control unit 3, specifically including an audible and visual alarm, a stop controller for ribbon weaving machine 6, and a human-machine interface. The audible and visual alarm is installed above the control panel of ribbon weaving machine 6 or in a prominent location in the workshop, employing an integrated design of an LED rotating warning light (red) and a buzzer (≥85dB). When control unit 3 determines that a disconnection has occurred and generates a level one alarm signal, the audible and visual alarm immediately activates, emitting a flashing red light and intermittent buzzing sound to alert the operator to handle the situation promptly. The alarm signal automatically deactivates after the disconnection is repaired and the system is reset.

[0059] The weaving machine 6 stop controller is connected in series with the main motor control circuit or clutch control circuit of the weaving machine 6. When the control unit 3 outputs a stop command, the weaving machine 6 stop controller immediately cuts off the main motor power or triggers the clutch to disengage, so that the weaving machine 6 stops running within a set time, effectively preventing the broken warp yarn 7 from continuing to get caught in the weaving loop, causing equipment damage or producing defective weaving tape.

[0060] The human-machine interface uses a 7-inch industrial touchscreen (model such as TPC7062Ti), which is installed on the control panel of the ribbon weaving machine. This interface displays the following information in real time: Current differential pressure sensor 104 reading P and threshold T1; Electrostatic signal value V of each electrode current(i) and the corresponding threshold T2(i); The timestamp of the moment the connection was lost; The specific interval number (width direction) where the broken thread is located is highlighted graphically on the simulated warp 7-width diagram.

[0061] In addition, the human-machine interface also integrates a one-click calibration button, which allows operators to touch to trigger the initialization learning process; it also has a manual reset button, which is used to manually clear the alarm status and turn off the power of the electrostatic induction unit after the disconnection is repaired.

[0062] With the external actuator 5 mentioned above, this system achieves real-time response, visualization, and automated control of the wire breakage detection results, significantly improving fault handling efficiency and the intelligence level of the production line.

[0063] Example 2 See Figure 2 This embodiment provides a method for detecting disconnection using the above system, including an initialization and adaptive learning phase and a real-time monitoring and disconnection handling phase.

[0064] I. Initialization and Adaptive Learning Phase After the equipment is powered on for the first time or after changing the product specifications, the operator presses the one-key calibration button, and the system automatically executes the following process: First, the control unit 3 activates the pneumatic unit. The baseline learning module continuously collects the air pressure values of the differential pressure sensor 104 for 30 - 50 cycles under normal weaving conditions, and calculates its average value as the dynamic baseline P. baseline According to the amplitude of the air pressure drop caused by thread breakage (experimentally determined to be about 15% - 30%), the system automatically sets the thread breakage determination threshold T1 to 80% of P. baseline This setting not only avoids false alarms caused by minor fluctuations in the air source but also ensures that single - thread breakage can be reliably detected.

[0065] Secondly, the control unit 3 briefly activates the electrostatic induction positioning unit. The electrostatic threshold learning module collects the signals of each metal induction electrode 201 during the normal operation of the warp yarn 7. After being processed by a high - impedance amplifier and a signal conditioning circuit, the electrostatic signal baseline V of each area is recorded. baseline（i） According to the characteristic that the signal amplitude drops below 30% of the baseline during thread breakage, the system automatically sets the thread breakage determination threshold T of each area 2(i) to 50% of V. baseline（i） This setting ensures that the signal drop during thread breakage can be accurately identified while allowing normal fluctuations caused by environmental humidity and yarn material differences.

[0066] Finally, the control unit 3 stores T1, T 2(i) and the electrode partition configuration information into the non - volatile memory to complete the adaptive learning.

[0067] The above initialization learning process is encapsulated and triggered by an external one - key calibration button. The system automatically executes the entire learning process without manual intervention in parameter settings, achieving rapid adaptation to different production specifications, and the adaptation switching time ≤ 10 minutes.

[0068] II. Real - time monitoring and thread breakage handling stage After the learning is completed, the system enters the real - time monitoring mode: At the warp yarn 7 guiding frame behind the webbing machine 6, a transverse uniform air flow is sprayed from one side to the other side along the width direction of the warp yarn 7 array through the air jet head 102. On the other side of the warp yarn 7 array, the air pressure value P corresponding to the overall resistance of the full - width warp yarn 7 to the air flow is detected in real - time through the pressure - taking port 103. Normal state monitoring: Only the pneumatic unit works, and the control unit 3 continuously compares the real - time air pressure value P with the threshold T1.

[0069] Level - 1 alarm (overall thread breakage judgment): When P < T1, the control unit 3 determines that a thread breakage has occurred and immediately generates a level - 1 alarm signal.

[0070] Level - 2 positioning: The control unit 3 supplies power to the electrostatic induction positioning unit, wakes up the unit, and collects the current signal values V of each electrode. current(i) .

[0071] Interval positioning: V current(i) Comparing with the corresponding T2(i), if the signal of only one electrode is below the threshold, the amplitude range corresponding to that electrode is directly located; if the signals of multiple adjacent electrodes are all below the threshold, it is determined that the breakage occurred at the boundary between the two zones (i.e., one warp yarn 7 breaks, but its influence covers the sensing area of ​​the adjacent electrodes), or multiple warp yarns 7 break simultaneously. This optimized positioning logic further improves the accuracy and practicality of positioning.

[0072] Output and Execution: Control unit 3 outputs the specific disconnection section number and issues a stop command. Operators can quickly locate the disconnection position and handle it based on the section information.

[0073] Reset: After troubleshooting, the operator can manually reset the system using the reset button on the control panel. The system will automatically turn off the power to the electrostatic induction unit, restore the low-power normal monitoring mode where only the pneumatic unit operates, and return to step 1 to continue execution.

[0074] In this example, the control unit 3 uses an STM32F407 series microcontroller, and the non-volatile memory is an EEPROM (model AT24C64); the one-key calibration button is a waterproof tactile button (model TC-01), which is installed on the operation panel of the ribbon machine 6. After being triggered, it sends a calibration signal to the microcontroller through the GPIO port.

[0075] This solution creatively designs a two-stage collaborative "pneumatic-electrostatic" yarn breakage detection mechanism, taking into account the dusty environment of ton bag production. The pneumatic unit, normally open as the first stage, utilizes its natural resistance to dust interference (airflow itself has a cleaning effect) for highly reliable and low-cost global monitoring. The electrostatic unit, as the second stage, activates only momentarily after an alarm, leveraging its extreme sensitivity to single yarn loss for rapid zone-based localization. This collaboration solves the technical challenge of using hundreds of electrostatic sensors to achieve high positioning accuracy, resulting in an extremely complex system, high cost, and poor long-term operational stability. It also avoids the yarn wear problem caused by mechanical detection for the sake of reliability. The timing coordination and functional complementarity of the two components under the control logic generate synergistic gains.

[0076] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0077] The embodiments have been described above, and such description is not restrictive. The figures shown are only one embodiment, and the actual structure is not limited to this. In short, if a person skilled in the art is inspired by this description and designs a similar structure and embodiment without departing from the inventive spirit, such design should fall within the scope of protection.

Claims

1. A thread breakage detection system for a webbing machine used in the production of ton bag straps, characterized in that, include: The overall pneumatic differential pressure detection unit (1) is used for non-contact status monitoring of the full-width warp yarn (7); The zone electrostatic induction positioning unit (2) responds to the disconnection signal of the overall pneumatic pressure difference detection unit (1) and locates the location where the disconnection occurs; The control unit (3) is electrically connected to the overall pneumatic differential pressure detection unit (1) and the partition electrostatic induction positioning unit (2) to receive signals, control the start and stop of the partition electrostatic induction positioning unit (2), and output alarm and shutdown signals. An adaptive configuration unit (4) is electrically connected to and integrated into the control unit (3) to enable the system to adapt to different warp yarn (7) counts in the webbing; An external actuator (5) is electrically connected to the control unit (3) and is used to perform corresponding actions in response to the instructions output by the control unit (3).

2. The thread breakage detection system for a weaving machine used in the production of ton bag straps according to claim 1, characterized in that, The overall pneumatic pressure difference detection unit (1) is a pneumatic detection unit that detects the overall resistance of the warp yarn based on the principle of pneumatic pressure difference. The overall pneumatic pressure difference detection unit (1) includes: A jet nozzle (102) is used to inject the airflow into the warp array along the width of the webbing; The pressure tap (103) is disposed on the other side of the warp array opposite to the jet head (102) and is used to sense the back pressure after the airflow passes through the warp array; A differential pressure sensor (104) is connected to the pressure tap (103) and is used to detect the back pressure value and output it as the first detection signal.

3. The thread breakage detection system for a weaving machine used in the production of ton bag straps according to claim 2, characterized in that, The opening of the pressure tap (103) is vertically downward, and the airflow ejected by the jet head (102) passes horizontally below its opening.

4. The thread breakage detection system for a weaving machine used in the production of ton bag straps according to claim 1, characterized in that, The partition electrostatic induction positioning unit (2) is an electrostatic induction positioning unit that detects the electrostatic signal of the warp yarn in each partition based on the principle of electrostatic induction. The partitioned electrostatic induction positioning unit (2) includes: Multiple metal sensing electrodes (201) are arranged at equal intervals along the width of the webbing to sense the electrostatic signals generated by the friction of the warp yarns in the corresponding sections. A high-impedance amplifier is connected to each metal sensing electrode (201) to amplify the electrostatic signal generated by the friction of the warp yarn (7) with high fidelity. The signal conditioning circuit, connected to each metal sensing electrode, includes a bandpass filter and an RMS conversion module, used to filter out power frequency interference and mechanical vibration noise, and convert the sensed electrostatic AC signal into a DC voltage characteristic value that characterizes its intensity, as the second detection signal output.

5. The thread breakage detection system for a weaving machine used in the production of ton bag straps according to claim 1, characterized in that, The control unit (3) is configured as follows: Under normal conditions, only the overall pneumatic differential pressure detection unit (1) is in operation, while the zone electrostatic induction positioning unit (2) is in a power-off standby state. When the differential pressure sensor (104) detects that the air pressure value P is lower than the set threshold T1, the control unit (3) determines that a disconnection has occurred, immediately generates a first-level alarm signal, and starts the partition electrostatic induction positioning unit (2). The partitioned electrostatic induction positioning unit (2) collects electrostatic signals V from each electrode after power-on. current(i) Compare it with its corresponding electrostatic baseline threshold T 2(i) Compare the signals and determine the bandwidth range where the line break occurs based on changes in signal strength. The control unit (3) outputs information about the disconnected area and issues a stop signal.

6. The thread breakage detection system for a weaving machine used in the production of ton bag straps according to claim 1, characterized in that, The adaptive configuration unit (4) includes: The baseline learning module is used to automatically acquire the readings of the differential pressure sensor (104) during system startup or manual calibration, and calculate the average value as the dynamic baseline P. baseline The disconnection threshold T1 is set to the dynamic baseline P. baseline Multiply by a preset scaling factor; The electrode configuration module is used to automatically calculate and prompt the electrode installation position and quantity based on the input total number of warp yarns (7) and positioning accuracy, and to store electrode grouping information; The electrostatic threshold learning module is used to automatically learn the signal amplitude of each electrode under normal weaving conditions and establish an electrostatic baseline V. baseline（i） And set the disconnection threshold T for each area. 2(i) Set as electrostatic baseline V baseline（i） Multiply by a preset scaling factor; The one-click calibration module is used to trigger the automatic configuration of all parameters and threshold calculation with a single click, simplifying the operation process.

7. A method for detecting thread breakage on a weaving machine used in the production of ton bag straps, characterized in that, It includes the initialization and adaptive learning phase and the real-time monitoring and disconnection handling phase.

8. The method for detecting thread breakage on a weaving machine used in the production of ton bag straps according to claim 7, characterized in that, The initialization and adaptive learning phase includes: a) Differential Pressure Baseline Learning: The pneumatic unit collects the air pressure values ​​of the differential pressure sensor (104) under normal weaving conditions for multiple cycles, and calculates the average value as the dynamic baseline P. baseline And set the disconnection detection threshold T1 to P baseline Multiply by a preset scaling factor; b) Electrostatic Baseline Learning: Briefly activate the electrostatic induction unit to collect the characteristic values ​​of each electrode signal, and record them as the electrostatic signal baseline V for each region. baseline（i） And set the disconnection threshold T for each area. 2(i) Set to V baseline（i） Multiply by a preset scaling factor; c) Parameter storage: Store T1, T 2(i) The electrode partition configuration information is stored in non-volatile memory.

9. The method for detecting thread breakage on a weaving machine used in the production of ton bag straps according to claim 7, characterized in that, The real-time monitoring and disconnection handling phase specifically includes the following steps: a) At the warp yarn (7) guide frame behind the weaving machine (6), a uniform transverse airflow is sprayed from one side of the warp yarn (7) array to the other side along the width direction through the jet nozzle (102); b) The air pressure value P corresponding to the overall resistance of the full width warp yarn (7) to the airflow is detected in real time through the pressure tap (103). Under normal conditions, only the pneumatic unit works, and the control unit (3) continuously compares the air pressure value P with the threshold T1. c) When the detected air pressure value P is lower than the preset disconnection judgment threshold T1, a disconnection is determined to have occurred; d) In response to the wire breakage determination, the control unit (3) immediately supplies power to the electrostatic induction positioning unit, starts the partition electrostatic induction positioning unit (2), and collects the electrostatic induction signal V of multiple electrodes arranged along the width direction. current(i) ; e) Convert the electrostatic induction signal V of each electrode current(i) and their respective electrostatic baseline thresholds T 2(i) Compare the signals and determine the amplitude range where the line break occurs based on changes in signal strength. f) Output the result containing information about the broken area, and control the weaving machine (6) to stop, trigger the audible and visual alarm, and display the broken area information on the human-machine interface.

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