Weaving machine non-stop weft yarn knot processing method and weaving machine
By installing a weft knot detection module and a piezoelectric sensor on the loom, weft knots are detected and processed. After detecting a knot, the loom delays weaving and switches the color selection index. The knot is carried away by the selvage warp yarn, which solves the problem of loom downtime caused by the failure to replace weft knots in time, and improves production efficiency and product quality.
Patent Information
- Application Number
- CN202511275747.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-08
- Publication Date
- 2025-11-11
AI Technical Summary
In loom production, uneven weft yarn consumption leads to the failure to replace weft yarn knots in a timely manner, causing the loom to stop and wait, which affects production efficiency. Existing technology makes it difficult to effectively handle weft yarn knots without stopping the machine to prevent them from being woven into the fabric.
The weft knot detection module uses a piezoelectric sensor to detect knots. The main control module controls the loom to delay weaving and switch color selection fingers. The selvage warp yarns carry away the knots, preventing them from entering the fabric. The loom stops only after all color selection fingers are exhausted.
It enables automatic handling of weft yarn knots on the loom without stopping the machine, reducing manual intervention, improving production efficiency, lowering the real-time requirements for workers, and reducing the production of defective products.
Smart Images
Figure CN120925152A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of textile-related technologies, specifically to a method for handling weft yarn knots on a loom without stopping the machine, and the loom itself. Background Technology
[0002] With technological advancements and industry development, the average skill level of textile industry employees has risen, significantly improving the stability of looms in daily production, reducing failure rates across the board, and substantially increasing the operating efficiency of the looms themselves. The focus of improving the daily production efficiency of looms has gradually shifted from addressing the inherent defects of the looms themselves to improving materials and processes.
[0003] Within existing factories, the workforce structure has undergone significant changes. Advances in looms have reduced the need for frontline workers. Previously, multiple workers were required for one loom; now, one worker is responsible for multiple looms. On the other hand, the two main raw materials used in daily production—warp and weft—have different consumption rates. Warp yarn is supplied by warp discs, with mainstream disc diameters ranging from 600 to 1250 mm, and warp lengths reaching several kilometers, almost matching the finished product length in some products, with a shrinkage rate of 6%-20%. Weft yarn, however, is supplied by weft bobbins, ranging in length from tens to several kilometers. In high-density fabrics, weft yarn consumption is substantial; a few meters of finished fabric may require the equivalent of one weft bobbin. This necessitates waiting for workers to replace the weft bobbins. Currently, with one worker responsible for multiple looms in the production workshop, delays in weft yarn replacement occur, leaving the looms idle and reducing production efficiency.
[0004] In daily industrial production, several solutions already exist to address this problem. One solution involves using two or more color-selecting fingers to cyclically switch between different raw materials. When the weft yarn corresponding to one color-selecting finger runs out, it switches to a color-selecting finger with unused raw materials. The current color-selecting finger awaits the addition of new weft yarn. After the addition, it can be reused on the machine. However, if the machine is not stopped, the weft knots at the junction of the old and new raw materials will be directly woven into the fabric, resulting in defective products. This method can consume multiple weft yarn bobbins in one weaving cycle, but to prevent weft knots from entering the fabric, manual intervention is unavoidable. Another approach involves connecting multiple weft yarn bobbins end-to-end, but this cannot effectively handle knots; they are assumed to be woven into the fabric and then removed by subsequent processes, which is time-consuming and labor-intensive. Against this backdrop, this solution provides a method that eliminates the need to stop the machine and avoids concerns about weft knots being woven into the fabric. Summary of the Invention
[0005] The purpose of this invention is to provide a method for handling weft yarn knots on a loom without stopping the machine, and a loom in general. Compared with existing loom handling solutions, this method can avoid frequent manual machine stop operations and eliminate concerns about defective products caused by yarn knots being woven in.
[0006] The present invention is achieved through the following technical solution.
[0007] The present invention provides a method for handling weft yarn knots on a loom without stopping the machine, comprising the following steps:
[0008] S1: Use the weft knot detection module to detect weft knots;
[0009] S2: When the weft yarn knot detection module is triggered by a weft yarn knot, it sends a signal to the main control module;
[0010] S3: The main control module controls the loom to continue weaving the set delay weft number based on the preset or calculated delay weft number;
[0011] S4: Entering the reset state. Reset state: The loom stops using the current channel and switches to using other color selection keys in the same group, waiting for the weft yarn knot to be taken away by the selvage warp yarn. When the fabric length exceeds the set stop weaving length, the reset state is exited.
[0012] S5: The loom resumes the use of the current channel and begins the next knot processing procedure.
[0013] Optionally, in step S2, the weft yarn knot detection module has two triggering modes;
[0014] The first type: The weft yarn knot detection module is triggered when the weft yarn knot passes through it;
[0015] The second type: The weft yarn knot detection module is triggered when the weft yarn knot leaves the weft yarn knot detection module.
[0016] Furthermore, the weft knot detection module has a trigger threshold. When the detected value is greater than the trigger threshold, the weft knot detection module is triggered and sends a signal to the main control module.
[0017] Furthermore, the weft knot detection module includes a piezoelectric sensor;
[0018] In the first triggering mode, the weft yarn is kept inside the piezoelectric sensor during the weft insertion process. The piezoelectric sensor continuously detects the pressure when the weft yarn passes by. The pressure change caused by the passing of the knot will be clearly distinguished from the smooth part. When the electrical signal exceeds the threshold, it is equivalent to detecting the weft yarn knot. At this time, a signal is given to the loom main control module.
[0019] In the second triggering mode: the weft yarn knot is placed inside the piezoelectric sensor. At this time, the piezoelectric sensor continuously gives the same signal. When the weft yarn of the current yarn bobbin is used up, the knot will be pulled out. There is no more weft yarn in the piezoelectric sensor, and the piezoelectric sensor signal is canceled (the detection threshold here is learned or set in advance). At this time, a signal is given to the loom main control module.
[0020] Furthermore, in step S3, the delayed weft number is the number of wefts woven after the knot signal is triggered. The formula for calculating the delayed weft number is: Delayed weft number = (Knot movement value - Safety distance) / Weft yarn length, where: Knot movement value: the length from the weft yarn knot detection sensor to the weft yarn scissors; Weft yarn length: the length of a single weft yarn woven.
[0021] Furthermore, in step S3, after the loom continues to weave the set delayed weft number, the following steps are also included: S31: The main control module determines whether the loom is in automatic knot removal state. If it is in automatic knot removal state, step S4 is executed; otherwise, the loom stops and waits for manual operation.
[0022] The automatic knot removal function can be toggled on / off by setting a corresponding switch.
[0023] Furthermore, in step S4, the stop weaving length is the amount of weaving stopped in the current channel. The formula for calculating the stop weaving length is: Stop weaving length = safety distance + knot movement value - current remaining weft introduction amount - weft yarn length * delay weft number.
[0024] Optionally, the safety distance ranges from 0 to 8000 mm, and preferably the safety distance is above 200 mm, i.e., 200 to 8000 mm.
[0025] A loom includes a weft knot detection module and at least two weft yarn bobbins, the loom being used to perform the above-described weft knot handling method without stopping the loom.
[0026] When the weft knot detection module adopts the first trigger mode, it can connect more than two weft yarn bobbins. When the weft knot detection module adopts the second trigger mode, it generally connects two weft yarn bobbins at the same time.
[0027] Furthermore, the weft yarn knot detection module includes a piezoelectric sensor.
[0028] The beneficial effects of the present invention are as follows: In this solution, by setting a weft yarn knot detection module for detecting knots, the loom stops using this channel after a knot is detected and switches to using other color selection fingers in the same group. By entering the reset state, the weft yarn knot is carried away by the twisted warp yarn, preventing the knot from being embedded in the fabric surface, thus eliminating the need for subsequent processing.
[0029] The loom will only stop after all the weft yarns on the color selection fingers are exhausted. As long as the workers replenish the weft yarns before all the weft yarns are used up, the loom can be kept running for a long time without stopping. This reduces the real-time requirements for workers in daily production and comprehensively improves the production efficiency of the workshop. Attached Figure Description
[0030] To more clearly illustrate the technical solutions in the embodiments of the 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 of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0031] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0032] Figure 1 A schematic diagram of the composition of the weft yarn supply module in a loom;
[0033] Figure 2 This is a schematic diagram of the weft yarn supply process in Example 1;
[0034] Figure 3 This is a schematic diagram of the weft yarn supply process in Example 2;
[0035] Figure 4 Flowchart for handling weft yarn knots on a loom without stopping the machine;
[0036] Figure 5 This is a schematic diagram of the weft yarn bobbin and weft yarn knot detection module in Example 2;
[0037] In the diagram: 1. Weft yarn spool 1; 2. Weft yarn spool 2; 3. Weft yarn spool 3; 4. Weft yarn knot detection module; 5. Weft yarn storage device; 6. Weft yarn detector; 7. Color selector; 8. Weft yarn scissors; 9. Detailed Implementation
[0038] The following is combined Figures 1-5 The present invention will be described in detail below.
[0039] A type of loom, such as Figure 1 Compared to existing loom handling solutions, this solution eliminates the need for manual machine shutdown and removes concerns about defective products caused by yarn knots being woven into the loom. The solution modifies the weft yarn supply module of the existing loom system, which consists of: a weft yarn knot detection module 5, a weft feeder 6, a weft yarn detector 7, a color selector 8, and a weft yarn scissors 9.
[0040] In this embodiment, the weft knot detection module 5 uses a weft knot detection sensor to detect weft knots. Internally, a piezoelectric sensor detects the weft yarn, and a processing unit processes the sensor signal differently in different operating modes. Finally, it converts the signal into an I / O signal according to the corresponding logic and sends it to the loom main control. The weft feeder 6 provides stable weft tension during the weft insertion process, ensuring stable weft insertion. When a weft yarn is missing, it sends a signal to the loom main control. The weft yarn detector 7 detects whether the weft yarn is broken during weft insertion. An analog signal is sent to the loom main control during weft insertion, and the signal stops when a break occurs. The color selector 8 consists of multiple color selection fingers, each corresponding to a yarn supply system. During the weft insertion process, the loom main control module controls which yarn supply system is used. The weft yarn scissors 9 cuts the weft yarn after weft insertion, separating the finished product from the yarn supply system.
[0041] The weft knot detection sensor has two modes: The first mode detects weft knots. This mode requires specific yarn properties; the weft yarn must remain inside the sensor during the weft insertion process. The piezoelectric sensor continuously detects the pressure as the weft yarn passes through. The pressure change caused by a knot is clearly distinguishable from a smooth section. After a pre-learning process, the sensor automatically sets the corresponding detection threshold. When the electrical signal exceeds the threshold, a weft knot is detected, and the processing unit sends a signal to the loom's main control module. The second mode detects the presence or absence of weft yarn. This mode is not limited by the thickness of the weft yarn and can be adapted to all types of weft yarn on the market. The weft knot is placed inside the sensor, and the piezoelectric sensor continuously sends the same signal to the processing unit. When the weft yarn in the current bobbin is used up, the knot is pulled out, and there is no more weft yarn inside the sensor. The piezoelectric sensor signal is then canceled. The detection threshold here is pre-learned or set, and the processing unit sends a signal to the loom's main control module.
[0042] Example 1:
[0043] In this embodiment, the loom uses the first of the two modes of the weft yarn knot detection sensor described above.
[0044] like Figure 2 The weft knot detection sensor is installed between weft bobbin 2 and weft feeder 6. During the weaving process, the yarn continuously passes through the weft knot detection sensor. Multiple weft bobbins are connected end-to-end, then pass through the weft knot detection sensor into the weft feeder, and then through the weft detector to the color selection index. The weft knot detection sensor can distinguish whether a knot has passed through, and sends a signal when a knot passes.
[0045] This solution can use multiple weft yarn cylinders. Its principle relies on piezoelectric sensors on the sensor to detect the signal quantity during yarn passage. When a knot occurs, the signal quantity will be significantly greater than at locations without knots, thus identifying the knot and transmitting a signal to the loom's main control module, which then completes the process of pulling the knot away.
[0046] This solution is preferably suitable for weaving yarns of moderate thickness. For both roving and fine yarns, the second mode in Example 2 is preferred.
[0047] Loom non-stop weft yarn knot handling process:
[0048] like Figure 4 Turn on the "knot detection" function in the loom system to put the loom into the knot detection state. It is preferable to set a switch to switch this state, such as setting a main knot detection switch, and use this switch to switch between knot detection and no detection.
[0049] When the main control module receives a weft knot signal, it compares it with the preset "knot detection filter" value. If the value is greater than the filter value, the signal is valid, and the loom angle at the trigger time is recorded. Among them: knot signal detection filter: the signal is only triggered if the duration exceeds the set value.
[0050] The loom angle at the trigger moment is used to determine whether it is within the weft insertion angle range. If it is, the "current remaining weft insertion amount" needs to be calculated. Loom weft insertion has an angle range: from the initial weft insertion angle to the weft release angle. If the sensor signal triggers within the weft insertion range, the remaining insertion amount needs to be calculated using the following formula:
[0051] Current remaining weft insertion amount = ((trigger angle - start weft insertion angle) / weft insertion interval angle range) * weft yarn length;
[0052] The angle range of weft insertion interval = weft release angle - starting weft insertion angle;
[0053] Generally, the initial weft insertion angle is 70 degrees, the weft release angle is 290 degrees, and the weft insertion interval angle range is 220 degrees. The weft insertion angle range is 70~290 degrees (within this range, the weft yarn is constantly moving, driven by the weft insertion mechanism).
[0054] The formulas for calculating the "delayed weft" and "stop weft" are as follows:
[0055] Delayed weft number = (knot movement value - safety distance) / weft yarn length;
[0056] Stop weaving length = safety distance + knot movement value - current remaining weft introduction amount - weft yarn length * delay weft number;
[0057] Wherein: Knot movement value: the length from the weft knot detection sensor to the weft scissors;
[0058] Weft yarn length: The length of a single weft yarn in weaving;
[0059] The safe distance ranges from 200 to 8000 mm;
[0060] Continue weaving with the delayed weft setting;
[0061] After the delayed weft weaving is completed, determine whether the loom is in automatic knot removal mode. If it is in the off state, the loom will stop directly and wait for manual operation; if it is in the on state, it will enter the reset state. In the reset state, the channel where the knot is located will not participate in normal weaving.
[0062] The automatic knot removal mode can be switched on / off by setting a corresponding switch. When the automatic knot removal switch is on, the loom is in the automatic knot removal mode. The purpose of setting this switch is that the automatic knot removal function is not suitable for all products. Rapier looms are a type of loom with very wide adaptability. The automatic knot removal function is suitable for products with a single weft yarn type.
[0063] Reset State: The loom stops using the current channel and switches to using other color selection fingers in the same group, waiting for the weft yarn knot to be carried away by the selvage warp yarn (if the color selection finger stops, it will be pulled away along with the selvage yarn. It's like pulling away the same distance as the number of meters of fabric woven. When the next color selection finger stops, the weft yarn scissors cut at the start of the weft insertion, at which point the knot is disconnected from the woven fabric, and then the scissor pulls the yarn over). When the recorded fabric length exceeds the "stop weaving length", the reset state is exited.
[0064] The loom resumes use of the current channel and begins the next knot processing procedure.
[0065] In practical daily use, each color selection finger corresponds to a weft yarn knot detection sensor. Multiple color selection fingers can be configured into the same group within the loom system to serve as substitutes for each other. The loom will only stop when all the weft yarns on all color selection fingers are exhausted. When one or more color selection fingers show a yarn shortage warning, it will be displayed on the screen and the loom indicator lights. Workers only need to replenish the weft yarns before all the bobbins are used up, allowing the loom to operate for extended periods without interruption. This reduces the real-time requirements for workers in daily production; only periodic inspections are needed, comprehensively improving workshop production efficiency.
[0066] Example 2:
[0067] In this embodiment, the loom uses the second of the two modes of the weft yarn knot detection sensor described above.
[0068] like Figure 3 , Figure 5 The weft yarn knot detection sensor is installed between weft yarn tube 1 2 and weft yarn tube 2 3. Weft yarn tube 1 2 and weft yarn tube 2 3 are connected end to end. The weft yarn knot generated by the connection is placed in the weft yarn knot detection sensor. During the weaving process, the weft yarn knot remains stationary in the weft yarn knot detection sensor 1. The yarn supply of weft yarn tube 1 2 reaches the color selection index through the weft storage device and the weft yarn detector.
[0069] In the second mode, when the weft yarn spool 2 is exhausted, the knot will be pulled out from the weft yarn knot sensor, at which point the weft yarn knot sensor will send a signal.
[0070] This solution is applied to the production of yarns such as slub yarn where knots are not easily distinguishable. Compared to Example 1, this example generally connects a maximum of two weft yarn bobbins at the same time.
[0071] Loom non-stop weft yarn knot handling process:
[0072] like Figure 4 The process from the start to the exit from the reset state is the same as the scheme in Example 1.
[0073] The difference lies in the operation when exiting the reset state and entering the next test. In this solution, after exiting the reset state, it will enter a waiting state. After manually placing a new weft yarn bobbin and connecting it with the previous weft yarn bobbin, the weft yarn knot is placed in the weft yarn knot detection sensor. At this time, the weft yarn knot detection sensor has no signal output for a long time, indicating that the new weft yarn bobbin has been placed, and thus enters the normal working test.
[0074] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand and implement the present invention. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.
Claims
1. A method for handling weft yarn knots on a loom without stopping the machine, characterized in that: Includes the following steps: S1: Use the weft knot detection module to detect weft knots; S2: When the weft yarn knot detection module is triggered by a weft yarn knot, it sends a signal to the main control module; S3: The loom continues to weave the set delay weft number; S4: Entering the reset state. Reset state: The loom stops using the current channel and switches to using other color selection keys in the same group, waiting for the weft yarn knot to be taken away by the selvage warp yarn. When the fabric length exceeds the set stop weaving length, the reset state is exited. S5: The loom resumes the use of the current channel and begins the next knot processing procedure.
2. The method for handling weft yarn knots on a loom without stopping the machine according to claim 1, characterized in that: In step S2, the weft knot detection module is triggered when the weft knot passes through it.
3. The method for handling weft yarn knots on a loom without stopping the machine according to claim 1, characterized in that: In step S2, the weft knot detection module is triggered when the weft knot leaves the weft knot detection module.
4. The method for handling weft yarn knots on a loom without stopping the machine, according to any one of claims 1-3, is characterized in that: The weft knot detection module has a trigger threshold. When the detected value is greater than the trigger threshold, the weft knot detection module is triggered and sends a signal to the main control module.
5. The method for handling weft yarn knots on a loom without stopping the machine, according to any one of claims 1-3, is characterized in that: In step S3, the formula for calculating the delay weft is: Delay weft = (knot movement value - safety distance) / weft yarn length, where: knot movement value: the length from the weft yarn knot detection sensor to the weft yarn scissors; weft yarn length: the length of a single weft yarn in weaving.
6. The method for handling weft yarn knots on a loom without stopping, as described in claim 5, is characterized in that: In step S3, after the loom continues weaving the set delay weft number, it also... The process includes the following steps: S31: The main control module determines whether the loom is in automatic knot removal mode. If it is in automatic knot removal mode, step S4 is executed; otherwise, the loom stops.
7. The method for handling weft yarn knots on a loom without stopping, as described in claim 5, is characterized in that: In step S4, the formula for calculating the stop length is: Stop length = Safety distance + Knot movement value - Current remaining weft introduction amount - Weft yarn length * Delayed weft number.
8. The method for handling weft yarn knots on a loom without stopping, as described in claim 7, is characterized in that: The safe distance ranges from 0 to 8000 mm.
9. A loom, characterized in that: The loom includes a weft yarn knot detection module and at least two weft yarn bobbins, and the loom is used to perform the weft yarn knot handling method without stopping the loom as described in any one of claims 1-8.
10. The loom according to claim 9, characterized in that: The weft yarn knot detection module includes a piezoelectric sensor.