Zipper sewing machine thread break controller

Abstract

A kind of zip sewing machine broken thread controller, including the installation plate for the passage of sewing thread, the installation plate outside is equipped with several thread inlet holes, several thread outlet holes and the thread tensioner between thread inlet hole and thread outlet hole, installation plate is equipped with broken thread detection device, broken thread detection device includes by sewing thread driven rotation and is located at the outside of installation plate thread wheel, the turntable of coaxial with thread wheel setting in the inside of installation plate, magnet along with turntable rotation, Hall sensor spaced from magnet induction, control board by Hall sensor signal transmission control zip sewing machine start-stop.By sewing thread driven thread wheel rotation, thread wheel drives fixed shaft, by fixed shaft driven turntable and magnet, in turn by the movement tension of sewing thread to drive turntable and magnet rotation, by Hall sensor to sense the strength variation of magnetic field to output the pulse high-low level with certain characteristics to determine whether broken thread, this detection mode has high sensitivity, long service life and will not produce noise.

Description

Technical Field

[0001] This invention relates to the field of sewing machines, and more particularly to a thread breakage controller for a zipper sewing machine. Background Technology

[0002] With the widespread adoption of automation in industrial sewing machines, sewing machines create one or more stitches on the fabric, weaving together one or more layers of stitches. During automated sewing, the thread may break or run out of thread due to various factors. The sewing machine must automatically alarm or provide a thread breakage signal to stop the machine and prevent empty needle sewing or damage to the fabric. Nylon zippers, on the other hand, operate automatically without human intervention during the sewing of the chain and fabric tape. This requires the sewing machine to automatically detect abnormal conditions of the fabric tape, chain, and thread, automatically stop the machine, and generate an alarm signal.

[0003] Currently, some sewing machines (such as coverstitch machines) are equipped with thread breakage detection devices. The thread breakage detection devices used in coverstitch machines are mechanical contact switches, similar to mechanical switches. Because coverstitch machines operate at high speeds, the switching frequency of these mechanical contact switches is high, generating invisible electric arcs at the contact points. Over time, oxidation occurs at the contact points, increasing contact resistance and affecting the lifespan of the mechanical contact switch. Furthermore, to ensure the reliability of the mechanical contact switch, the spring used in it must be pre-stressed with a certain strength when in contact with the opposite electrode. Therefore, this type of mechanical contact switch often fails when the thread tension is low. In addition, mechanical contact switches are susceptible to interference from lint and oil, leading to poor contact and malfunction. They also generate noise during use. Currently, production equipment uses mechanical contact thread breakage stop switches, which generate a stop signal by falling under their own weight and activating the circuit after a thread breaks. However, these switches have several drawbacks: 1. Mechanical contacts are prone to dirt and oxidation, resulting in poor contact; 2. After the thread breaks, it gets stuck in the product, causing tension to persist and the thread to break continuously; 3. There is a signal delay, and the machine cannot stop immediately after a thread breakage. These three problems lead to a large number of defective products. Summary of the Invention

[0004] This invention aims to solve the problems existing in the prior art by providing a thread breakage controller for a zipper sewing machine. It uses a Hall sensor to detect whether the sewing machine has broken threads. This method does not require physical contact with the Hall sensor, has a long service life, does not generate noise, and has high sensitivity to quickly detect thread breaks. A baffle is also provided on the thread wheel to prevent broken threads from detaching from the thread wheel.

[0005] The technical solution adopted by this invention to solve its technical problem is as follows: This zipper sewing machine thread breakage controller includes a mounting plate for the sewing thread to pass through. The outer side of the mounting plate has several thread inlet holes, several thread outlet holes, and a thread tensioner located between the thread inlet holes and the thread outlet holes. A thread breakage detection device is mounted on the mounting plate. The thread breakage detection device includes a thread wheel driven by the sewing thread and located on the outer side of the mounting plate; a turntable coaxially arranged on the inner side of the mounting plate with the thread wheel; a magnet rotating with the turntable; Hall sensors spaced apart from the magnet; and a control board that sends signals from the Hall sensors to control the start and stop of the zipper sewing machine. The Hall sensors, in conjunction with the magnet, provide high sensitivity, enabling timely stopping of the sewing machine and minimizing losses.

[0006] To further refine the design, the thread tensioner is positioned close to the suture inlet. The suture enters through the inlet and is tensioned by the tensioner. The thread wheel is offset from the tensioner, allowing the tensioned suture to adhere to the outer circumference of the wheel and form a defined area around it. This offsetting arrangement ensures that the tensioned suture adheres to the surface of the thread wheel and rotates it.

[0007] Further improvements include coaxial mounting of the reel and turntable on the inner and outer sides of the mounting plate via a fastener. The fastener is fixed to the mounting plate, and a bearing and a through-bearing fixed shaft are installed in the middle of the fastener. The reel is mounted at one end of the fixed shaft, and the turntable is mounted at the other end. The fastener ensures that the reel, fixed shaft, and turntable are stably mounted on the mounting plate.

[0008] Further improvements include the addition of a pair of bearings, spaced apart and coaxially arranged, with the fixed shaft mounted within the pair of bearings. This pair of bearings enhances the stability of the fixed shaft within the fixture, preventing tilting or displacement during operation.

[0009] Further improvements include an upward-extending baffle on one side of the fixing component that blocks the thread pulley. The baffle is spaced apart from the outer circumference of the thread pulley and prevents the suture thread from detaching from it. This baffle on the fixing component side prevents the suture thread from breaking and detaching from the thread pulley when under tension, as subsequent re-threading would be cumbersome and time-consuming.

[0010] Further improvements include mounting slots on the turntable for placing magnets. Several mounting slots are arranged at intervals around the turntable. These slots allow the magnets to be stably mounted on the turntable.

[0011] Further improvements include placing the magnet on the inner surface of the turntable, while the outer surface of the turntable is flat, with the magnet and Hall sensor positioned at close intervals. This spacing between the magnet and Hall sensor prevents them from exhibiting patterns that could degrade performance.

[0012] Further improvements include a control switch on the control panel to control the sewing machine's operating mode. The operating mode is switched by processing signals on the control panel. Having two operating modes improves the sewing machine's usability while reducing costs.

[0013] Further improvements include S1 multi-channel signal acquisition: As multiple turntables rotate with their corresponding reels, the magnets on each turntable continuously transmit electromagnetic signals to the Hall sensor. When the Hall sensor detects a change in the magnetic field, it outputs a low level. If the magnet on a turntable stops transmitting electromagnetic signals to the Hall sensor, and the Hall sensor does not detect a change in the magnetic field, it outputs a high level. S2 Electromagnetic Signal Detection: The Hall effect detection circuit detects electromagnetic signals from multiple channels respectively. The detection of whether the electromagnetic signal is low or high level determines whether it is a normal state or a disconnection state. S3 processes the signal through filtering, and the signal is input to the microcontroller system. The microcontroller system outputs working status indicator lights, running status control outputs, and warning light control outputs.

[0014] Further improvements include a microcontroller system connected to a power supply unit, which is an AC power supply. The AC power supply is connected to a rectifier and filter, which in turn is connected to a voltage regulator, an EMC anti-interference circuit, and an anti-static interference circuit.

[0015] The beneficial effects of this invention are as follows: This invention uses a suture thread to drive a rotating thread wheel, which in turn drives a fixed shaft and a turntable and magnet driven by the fixed shaft. The tension of the suture thread further drives the rotation of the turntable and magnet. A Hall sensor detects changes in the strength of the magnetic field and outputs a pulsed high / low level signal to determine if the thread is broken. This detection method is highly sensitive, has a long service life, and produces no noise. The suture thread drives a guide wheel, which in turn drives a plastic wheel with four neodymium iron boron magnets to rotate synchronously. The PCB board receives the detection signal, which is processed and judged by a microcontroller. If the guide wheel does not rotate or rotates too slowly, a stop signal and an external 24V abnormal alarm signal are issued. The system stops immediately within 50 milliseconds, and the alarm light illuminates, allowing staff to promptly see and handle the abnormal signal. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a side view of the wire breakage detection device; Figure 3 This is a structural diagram of the reel, bearing, turntable, and fixed shaft.

[0017] Figure 4 A structural diagram of the reel, turntable, fixed shaft, and fixing components; Figure 5This is a schematic diagram of the control board. Figure 6 This is a schematic diagram of the thread reel structure; Figure 7 This is the schematic diagram of the control board under DC power conditions. Figure 8 This is the schematic diagram of the control board under AC power conditions.

[0018] Explanation of reference numerals in the attached drawings: 1. Mounting plate; 2. Inlet hole; 3. Outlet hole; 4. Wire tensioner; 5. Wire breakage detection device; 6. Wire reel; 7. Turntable; 8. Magnet; 9. Hall sensor; 10. Control board; 11. Fixing component; 12. Bearing; 13. Fixing shaft; 14. Baffle; 15. Mounting groove; 16. Control switch. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Those skilled in the art will be able to implement the present invention based on these descriptions. Furthermore, the embodiments of the present invention described below are generally only some, not all, of the embodiments of the present invention. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0020] See attached document Figure 1 This embodiment provides a zipper sewing machine thread breakage controller, including a mounting plate 1 for the sewing thread to pass through. The outer side of the mounting plate 1 is provided with a plurality of thread inlet holes 2, a plurality of thread outlet holes 3, and a thread tensioner 4 located between the thread inlet holes 2 and the thread outlet holes 3. The key feature is that a thread breakage detection device 5 is installed on the mounting plate 1. The thread breakage detection device 5 includes a thread wheel 6 driven to rotate by the sewing thread and located on the outer side of the mounting plate 1, a turntable 7 coaxially arranged on the inner side of the mounting plate 1 with the thread wheel 6, a magnet 8 rotating with the turntable 7, a Hall sensor 9 spaced apart from the magnet 8, and a control board 10 that sends signals from the Hall sensor 9 and controls the start and stop of the zipper sewing machine. The thread tensioner 4 is located near the thread inlet hole 2. The suture enters through the thread inlet hole 2 and is tensioned by the thread tensioner 4. The thread reel 6 is offset from the thread tensioner 4, and the tensioned suture adheres to the outer circumference of the thread reel 6 and surrounds a certain area around it. Each thread tensioner 4 has a corresponding matching thread inlet hole 2. The advantage of this is that the suture is first passed through the thread inlet hole 2 and then wound around the thread tensioner 4 that matches the thread inlet hole 2. This prevents the suture that should be wound on the first thread tensioner 4 from being wound on the second thread tensioner 4, and vice versa. This would cause the sutures above the thread tensioner 4 to become entangled, resulting in the suture getting stuck above the thread tensioner 4 and causing the suture to break. Because the suture will be under tension under the action of the thread tensioner 4, making the suture taut, in order to ensure that the taut suture is in close contact with the surface of the thread wheel 6, the thread wheel 6 and the thread tensioner 4 are offset. For details, please refer to the appendix. Figure 1 As shown, in this embodiment, the thread outlet 3 is located on the left side of the mounting plate 1, and the thread wheel 6 is located on the side of the thread tensioner 4 away from the thread outlet 3, that is, the thread wheel 6 is located on the right side relative to the thread tensioner 4. In use, the suture is pulled out from the thread tensioner 4, passes around the right side of the thread wheel 6, and then pulled toward the thread outlet 3. Since the suture is under tension and is in a taut state, the suture is kept close to the outer end face of the thread wheel 6 in the misaligned installation state, so that the suture is in close contact with the outer end face of the thread wheel 6. Under the action of friction, the movement of the suture drives the rotation of the thread wheel 6. The rotation of the thread wheel 6 drives the fixed shaft 13, the turntable 7, and the magnet 8 installed on the turntable 7 to rotate in sequence. The rotating magnet generates an intermittent active magnetic field. The Hall sensor 9 senses the intermittent active magnetic field to determine whether the turntable 7 is rotating, and thus can determine whether the thread wheel 6 is rotating and whether the suture has broken and stopped moving.

[0021] Specifically, the spool 6 and the turntable 7 are coaxially mounted on the inner and outer sides of the mounting plate 1 via a fixing member 11. The fixing member 11 is fixed to the mounting plate 1. A bearing 12 and a fixing shaft 13 passing through the bearing 12 are installed in the middle of the fixing member 11. The spool 6 is installed at one end of the fixing shaft 13, and the turntable 7 is installed at the other end of the fixing shaft 13. The fixing member 11 has a through hole in its center. The spool 6 is located on the outer side of the mounting plate 1, and the turntable 7 is located on the inner side of the mounting plate 1, so that the spool 6 and the turntable 7 are respectively fixedly installed at both ends of the fixing shaft 13. The fixing member 11 is fixedly installed on the outer surface of the mounting plate 1 by screws. The bearing 12 is installed in the central through hole of the fixing member 11, and the fixing shaft 13 passes through the bearing 12. Further, refer to the appendix. Figure 3As shown, in this embodiment, there is a pair of bearings 12, which are spaced apart and coaxially arranged. A fixed shaft 13 is installed within the pair of bearings 12. To ensure the bearings 12 can be stably installed in the through-hole at the center of the fixing member 11, the bearings 12 and the fixing member 11 are interference-fitted. Specifically, the diameter of the hole at the center of the fixing member 11 is slightly smaller than the outer diameter of the bearing 12. Because the fixing member 11 is made of plastic and has a certain degree of flexibility, a certain amount of external force is required when installing the bearings 12 to drive them into the through-hole at the center of the fixing member 11. Simultaneously, the fixing member 11... The central through hole will undergo a certain deformation, allowing the fixing member 11 to tightly wrap the bearing 12 installed inside the fixing member 11. At the same time, there are two bearings 12, which are inserted from both ends of the central through hole of the fixing member 11. In order to prevent the bearing 12 at one end from being placed too deep during installation, which would prevent the other bearing 12 from being fully installed inside the fixing member 11, an inwardly protruding partition wall is provided on the inner wall of the fixing member 11. Using two bearings 12 can increase the contact area with the fixed shaft 13, thereby improving the stability of the fixed shaft 13 installed in the fixing member 11.

[0022] Since the spool 6 rotates due to the movement of the sewing thread, the thread contacts one side of the spool 6 rather than being wound around it. Typically, the thread breaks at the point where the sewing machine stitches the thread. Because the thread is under tension during stitching, when it breaks at the sewing point, it springs away from the spool 6 under this tension, detaching from it. Subsequent adjustments require the thread to be repositioned onto the spool 6, which is cumbersome. (See attached diagram.) Figure 4 As shown, in this embodiment, a baffle 14 extending upward and blocking one side of the thread wheel 6 is provided on one side of the fixing member 11. The baffle 14 is spaced apart from the outer periphery of the thread wheel 6 and prevents the suture from coming off the thread wheel 6. Specifically, the baffle 14 is spaced apart from the outer periphery of the thread wheel 6 and the top of the baffle 14 is higher than the outer surface of the thread wheel 6. Thus, when the suture breaks, the baffle 14 limits the suture on the thread wheel 6 and prevents the suture from popping off the thread wheel 6. The gap between the baffle 14 and the thread wheel 6 can be smaller than the diameter of the suture, so as to ensure that the suture will not come off the gap between the thread wheel 6 and the baffle 14.

[0023] See attached document Figure 6 As shown, in order to ensure that the magnet 8 can be stably installed on the turntable 7, the turntable 7 is provided with a mounting groove 15 for placing the magnet 8. There are several mounting grooves 15 arranged around the turntable 7 at intervals. More preferably, in this embodiment, there are four magnets 8 and mounting grooves 15, and the interval angle between two adjacent mounting grooves 15 is 90 degrees. Four magnets 8 are sufficient to meet the detection performance of the wire breakage detection device 5.

[0024] See attached document Figure 5 As shown, in order to improve the service life of the wire breakage detection device 5, the magnet 8 is set on the inner surface of the turntable 7, the outer surface of the turntable 7 is flat, and the magnet 8 and the Hall sensor 9 are set at close intervals. Specifically, the outer surface of the turntable 7 and the Hall sensor 9 are set at close intervals, while the magnet 8 is set inside the turntable 7 and its height does not exceed the inner surface of the turntable 7. This arrangement not only enables the Hall sensor 9 to sensitively sense changes in the magnetic field, but also prevents frictional contact between the Hall sensor 9 and the magnet 8. Long-term frictional contact will cause severe wear of the Hall sensor 9, thereby causing the Hall sensor 9 to malfunction and become unable to detect wire breakage.

[0025] Reference Appendix Figure 7 , 8 The disconnection controller in this embodiment also includes a microcontroller mounted on the control board 10, a warning light and a work light mounted on the control board 10, and a DC power supply for powering the control board 10. The Hall sensor is electrically connected to the signal input terminal of the microcontroller. In this embodiment, the Hall sensor 9 is mounted on the control board 10. The control board 10 can also be powered by AC power. The AC power supply is connected to a rectifier and filter, which is connected to a voltage regulator, an EMC anti-interference circuit, and an anti-static interference circuit, allowing the sewing machine to work under different conditions. The specific working principle is as follows: S1 Multi-channel Signal Acquisition: When multiple turntables rotate with their corresponding reels, the magnets on the turntables continuously send electromagnetic signals to the Hall sensor. When the Hall sensor senses a change in the magnetic field, it outputs a low level. If the magnet on a turntable stops sending electromagnetic signals to the Hall sensor, the Hall sensor does not sense a change in the magnetic field and outputs a high level. S2 Electromagnetic Signal Detection: The Hall effect detection circuit detects electromagnetic signals from multiple channels respectively. The detection of whether the electromagnetic signal is low or high level determines whether it is a normal state or a disconnection state. S3 processes the signal through filtering, and the signal is input to the microcontroller system. The microcontroller system outputs working status indicator lights, running status control outputs, and warning light control outputs.

[0026] When in use, the work light is on normally. The turntable 7 and magnet 8 are rotated by the thread wheel 6. The changing magnetic field is detected by the Hall sensor 9, which is spaced apart from the magnet 8. When the suture breaks, the Hall sensor 9 transmits the detection signal to the microcontroller. After processing by the microcontroller, the signal is transmitted to the sewing machine, thereby controlling the sewing machine to stop and the warning light to turn on while the work light turns off.

[0027] See attached document Figure 5To improve the practicality of the sewing machine, the control board 10 is equipped with a control switch 16 for controlling the working mode of the sewing machine. Currently, the mainstream sewing stitches on the market are four-thread and six-thread. The control switch 16 is connected to the input terminal of the microcontroller. Through the control switch 16, the microcontroller can receive or output signals from four Hall sensors 9 or six Hall sensors 9, thereby switching the working mode of the sewing machine to four-thread mode or six-thread mode.

[0028] Certain terms are used in the specification and claims of this invention to refer to specific products. Those skilled in the art will understand that manufacturers may use different names to refer to the same components. This document is not intended to distinguish between components that have the same function but different names. In the following specification and claims, words such as “comprising,” “having,” and “including” are open-ended terms and should therefore be interpreted as “containing but not limited to…”.

[0029] The above are preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A zipper sewing machine thread breakage controller, comprising a mounting plate (1) for the thread to pass through, wherein the outer side of the mounting plate (1) is provided with a thread inlet (2), a thread outlet (3), and a thread tensioner (4) located between the thread inlet (2) and the thread outlet (3), characterized in that: The mounting plate (1) is equipped with a thread breakage detection device (5). The thread breakage detection device (5) includes a thread wheel (6) driven by the suture thread and located on the outside of the mounting plate (1), a turntable (7) coaxially arranged on the inside of the mounting plate (1) with the thread wheel (6), a magnet (8) mounted on the turntable and rotating with the turntable (7), a Hall sensor (9) spaced apart from the magnet (8), and a control board (10) that sends signals from the Hall sensor (9) and controls the start and stop of the zipper sewing machine. The spool (6) and the turntable (7) are coaxially fixed on the inner and outer sides of the mounting plate (1) by a fixing member (11). The fixing member (11) is fixed on the mounting plate (1). A bearing (12) and a fixed shaft (13) passing through the bearing (12) are installed in the middle of the fixing member (11). The spool (6) is installed at one end of the fixed shaft (13), and the turntable (7) is installed at the other end of the fixed shaft (13). The thread tensioner (4) is close to the thread inlet (2). The suture enters from the thread inlet (2) and is tensioned by the thread tensioner (4). The thread wheel (6) is offset from the thread tensioner (4). The tensioned suture adheres to the outer periphery of the thread wheel (6) and surrounds a certain area around the outer periphery. The fixing member (11) has a baffle (14) extending upward and blocking one side of the thread wheel (6). The baffle (14) is spaced apart from the outer periphery of the thread wheel (6) and prevents the suture from detaching from the thread wheel (6).

2. The zipper sewing machine thread breakage controller according to claim 1, characterized in that: There is a pair of bearings (12), the pair of bearings (12) are spaced apart and coaxially arranged, and the fixed shaft (13) is installed in the pair of bearings (12).

3. A zipper sewing machine thread breakage controller according to claim 1, characterized in that: The turntable (7) is provided with mounting slots (15) for placing magnets (8), and there are several mounting slots (15) arranged around the turntable (7) at intervals.

4. A zipper sewing machine thread breakage controller according to claim 1, characterized in that: The magnet (8) is disposed on the inner surface of the turntable (7), the outer surface of the turntable (7) is a planar structure, and the magnet (8) and the Hall sensor (9) are disposed at close intervals.

5. A zipper sewing machine thread breakage controller according to claim 1, characterized in that: The control board (10) is equipped with a control switch (16) for controlling the working mode of the suture machine. The working mode of the suture machine is switched by controlling the processing signal on the control board (10).

6. The control method for a zipper sewing machine thread breakage controller according to claim 1: characterized in that: The steps are as follows: S1 Multi-channel signal acquisition: When multiple turntables (7) rotate with their corresponding reels (6), the magnets (8) on the multiple turntables (7) continuously transmit electromagnetic signals to the Hall sensor (9). When the Hall sensor (9) senses a change in the magnetic field, it outputs a low level. If the magnet (8) on a certain turntable (7) stops transmitting electromagnetic signals to the Hall sensor (9), the Hall sensor (9) does not sense a change in the magnetic field and outputs a high level. S2 Electromagnetic Signal Detection: The Hall effect detection circuit detects electromagnetic signals from multiple channels respectively. The detection of whether the electromagnetic signal is low or high level determines whether it is a normal state or a disconnection state. S3 processes the signal through filtering, and the signal is input to the microcontroller system. The microcontroller system outputs working status indicator lights, running status control outputs, and warning light control outputs.

7. The control method for a zipper sewing machine thread breakage controller according to claim 6: characterized in that: The microcontroller system is connected to a power supply section, which is an AC power supply. The AC power supply is connected to a rectifier and filter, which is connected to a voltage regulator, an EMC anti-interference circuit, and an anti-static interference circuit.

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