A yarn sticking alarm device for robot laser welding
Patent Information
- Application Number
- CN202522545203.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-01
- Publication Date
- 2026-10-23
- Estimated Expiration
- 2035-12-01
AI Technical Summary
[0003]现有机器人激光填丝焊接技术中，粘丝问题是影响焊接质量、设备安全性及作业连续性的关键技术痛点，现有技术尚未形成有效的解决方案，具体缺陷如下：一、现有防粘丝控制多采用延长焊接终点激光出光时间的单一方式，通过持续加热焊丝末端以避免粘连
[0013]1、本实用新型通过第一光电隔离电路、第二光电隔离电路组成的双光电隔离电路与继电器结合的设计，在焊接结束退丝阶段，通过导丝杆、焊丝、工件和地的闭合回路检测粘连信号，解决了现有技术无法有效识别粘丝情况的痛点。在粘丝发生时，机器人控制器可快速触发示教器报警并暂停送丝机退丝操作或机器人运行，避免强行拖拽导致的设备损坏、工件报废，消除操作人员安全隐患。
Smart Images
Figure CN224879662U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of laser welding technology and relates to a wire sticking alarm device for robotic laser welding. Background Technology
[0002] Laser welding is a welding technology that uses a high-energy-density laser beam as a heat source. It boasts significant advantages such as high welding speed, small heat-affected zone, deep penetration, and minimal workpiece deformation. Its applications are flexible and diverse, encompassing handheld laser welding, dedicated laser welding machines, and robotic laser welding, and are widely applicable to precision manufacturing, sheet metal processing, the automotive industry, aerospace, and many other fields. For scenarios with large weld gaps or high welding performance requirements, a wire feeder is necessary. This feeder delivers welding wire to the laser welding torch, which melts and fills the weld gap, significantly improving weld quality and joint reliability.
[0003] In existing robotic laser wire feeding welding technology, wire sticking is a key technical challenge affecting welding quality, equipment safety, and operational continuity. Current technologies lack effective solutions, with the following specific shortcomings: 1. Existing anti-sticking control methods primarily rely on extending the laser emission time at the welding endpoint to continuously heat the wire tip and prevent sticking. However, this approach easily leads to excessive melting and balling of the wire tip, and even dry burning of the base material, directly causing weld tail defects. Furthermore, when the laser emission power and wire feed speed parameters are mismatched, the anti-sticking effect is significantly reduced, failing to meet the demands of complex welding conditions. 2. Existing technologies lack a dedicated wire sticking detection module and alarm function. When wire sticking occurs during welding, the robot cannot promptly identify the fault and continues operating according to the preset program. This problem easily leads to the risk of forcibly pulling the workpiece, potentially damaging the welding equipment, scrapping the workpiece, and posing safety hazards to on-site operators, severely impacting operational safety and production efficiency. Summary of the Invention
[0004] The purpose of this invention is to address the aforementioned problems in the existing technology by proposing a wire-sticking alarm device for robotic laser welding. The technical problem it aims to solve is: how to improve the safety of robotic welding operations.
[0005] The objective of this utility model can be achieved through the following technical solution: A wire-sticking alarm device for robotic laser welding includes a robot I / O board and a robot controller. The wire-sticking alarm device also includes a relay K1. The robot I / O board is provided with a first opto-isolation circuit, a second opto-isolation circuit, and an MCU for outputting a low-level signal at the end of the welding operation. The MCU is connected to the input terminal of the second opto-isolation circuit. The output terminal of the second opto-isolation circuit is connected in series with the coil of the relay K1 to ground. The input terminal of the first opto-isolation circuit is connected to a switch contact of the relay K1. The other switch contact of the relay K1 is connected to a detection feedback line for connecting to the wire guide rod to obtain a signal indicating wire sticking to the workpiece. The output terminal of the first opto-isolation circuit is connected to the MCU. The MCU is used to confirm whether the wire sticks to the workpiece based on the level signal output by the first opto-isolation circuit. The MCU is connected to the robot controller through the robot I / O board. The robot controller is also connected to a teach pendant for alarming when the wire sticks to the workpiece.
[0006] In this wire-sticking alarm device for robotic laser welding, the MCU and robot controller communicate in real time via the robot's I / O board. At the end of the welding operation, the robot controller first shuts off the "wire feed" signal, and the wire feeder immediately stops feeding wire. Subsequently, the controller sends a wire-sticking detection signal while initiating the retraction action. Upon receiving this signal, the MCU outputs a low-level signal to the second opto-isolation circuit, causing it to conduct and drive relay K1 to engage. After relay K1 is activated, the robot controller sends a "wire retraction" signal, and the wire feeder begins the retraction action. If the welding wire sticks to the workpiece at this time, a closed loop is formed between the welding wire, the wire guide rod, the workpiece, and ground. The detection feedback line becomes low-level, and the input of the first opto-isolation circuit receives this low-level signal and becomes active. After detecting the low-level signal output by the first opto-isolation circuit, the MCU transmits it to the robot controller. The robot controller determines that the robot end has contacted the workpiece based on the duration of the signal, thus confirming that the welding wire is stuck together. At this time, the robot controller controls the wire feeder to stop running and controls the teach pendant to sound an alarm, promptly reminding the operator to handle the situation and avoid potential risks caused by the robot forcibly dragging the workpiece due to the stuck wire, thereby improving the safety of equipment operation.
[0007] In the aforementioned wire adhesion alarm device for robotic laser welding, the first opto-isolation circuit includes an optocoupler U1, resistors R1, R2, and R3, a voltage VCC, and a power supply voltage. One input terminal of the optocoupler U1 is connected to one end of resistor R2, and the other end of resistor R2 is connected to the power supply voltage. The other input terminal of the optocoupler U1 is connected to one end of resistor R3, and the other end of resistor R3 is connected to the switch contact of relay K1. One output terminal of the optocoupler U1 is connected to the voltage VCC through resistor R1, and another output terminal of the optocoupler U1 is also connected to the MCU. The other output terminal of the optocoupler U1 is grounded. The optocoupler U1 includes an input terminal of a bidirectional diode and an output terminal of a phototransistor. When the welding wire adheres to the workpiece, the welding wire, the wire guide rod, the workpiece, and ground form a closed loop. The bidirectional diode of the optocoupler U1 conducts, thereby turning on the phototransistor. The collector of the phototransistor is connected to the MCU, and the MCU receives a low-level signal, thus confirming that the welding wire adheres to the workpiece.
[0008] In the above-mentioned wire sticking alarm device for robotic laser welding, the second opto-isolation circuit includes an optocoupler U2 and a resistor R4. One input terminal of the optocoupler U2 is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the MCU. The other input terminal of the optocoupler U2 is connected to the voltage VCC. One output terminal of the optocoupler U2 is connected to the power supply voltage, and the other output terminal of the optocoupler U2 is connected to the coil of the relay K1. Optocoupler U2 includes an input side of a diode and an output side of a transistor. The cathode of the diode on the input side is connected to the MCU through resistor R4. When the MCU outputs a low-level signal to optocoupler U2, the diode on the input side conducts, causing the transistor on the output side to conduct. This forms a circuit between the power supply voltage, the transistor on the output side, the coil of relay K1, and ground. After the coil of relay K1 is energized, the switch contacts of relay K1 close. When the welding wire adheres to the workpiece, the power supply voltage, the bidirectional diode of optocoupler U1, the detection feedback line, the wire guide rod, the welding wire, the workpiece, and ground form a closed circuit. The MCU will detect the low-level signal output by the first opto-isolation circuit and send it to the robot controller. The robot controller thus obtains that the welding wire and the workpiece are adhered.
[0009] In the aforementioned wire-sticking alarm device for robotic laser welding, the second opto-isolation circuit further includes a diode D1. The anode of diode D1 is connected to the coil of relay K1, and the cathode of diode D1 is connected to the power supply voltage. The parallel connection of diode D1 on the phototransistor side of optocoupler U2 provides a discharge path for the reverse electromotive force generated during power-off, preventing the phototransistor and other semiconductor components from being damaged during power-off, thus ensuring stable circuit operation.
[0010] In the aforementioned wire-sticking alarm device for robotic laser welding, the robot's I / O board is further equipped with an output port and an input port. The input port is connected to the resistor R3 and the switch contact of the relay K1, respectively, and the output port is connected to the positive terminal of the diode D1 and the coil of the relay K1, respectively. The inclusion of the input and output ports facilitates connection to other devices such as the relay K1.
[0011] In the aforementioned wire-sticking alarm device for robotic laser welding, an indicator light is connected in parallel across the coil of relay K1 to detect whether relay K1 is faulty. When the indicator light is off, it may indicate that the coil is not powered (e.g., lack of control signal, open circuit) or that the coil itself is burnt out (open circuit), resulting in no current flow. By setting the indicator light, the fault point can be quickly located, ensuring the reliability of this wire-sticking alarm device.
[0012] Compared with existing technologies, the wire sticking alarm device for robotic laser welding has the following advantages:
[0013] 1. This utility model utilizes a dual opto-isolation circuit (comprising a first opto-isolation circuit and a second opto-isolation circuit) combined with a relay design. During the wire retraction stage after welding, it detects adhesion signals through a closed loop connecting the wire guide rod, welding wire, workpiece, and ground, thus solving the problem of existing technologies' inability to effectively identify wire adhesion. When wire adhesion occurs, the robot controller can quickly trigger a teach pendant alarm and pause the wire retraction operation of the wire feeder or the robot's operation, preventing equipment damage and workpiece scrapping caused by forced dragging and eliminating safety hazards for operators.
[0014] 2. This utility model, through the design of dual opto-isolation circuits and diode D1, can block electromagnetic interference, protect semiconductor components, ensure stable operation of detection and control circuits, and reduce the probability of failure. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the circuit structure of this utility model.
[0016] In the diagram, 1. Robot I / O board; 10. MCU; 11. Output port; 12. Input port; 13. First opto-isolation circuit; 13a. Power supply voltage; 14. Second opto-isolation circuit; 2. Robot controller; 3. Teach pendant; 4. Wire feeder; 5. Wire feeder driver; 6. Detection feedback line; 7. Wire guide rod; 8. Power cord; 9. Workpiece. Detailed Implementation
[0017] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be further described in detail below with reference to the accompanying drawings. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.
[0018] like Figure 1 As shown, the wire sticking alarm device for robotic laser welding includes a robot I / O board 1, a teach pendant 3, a robot controller 2, and a relay K1. The robot controller 2 is connected to the teach pendant 3. The robot I / O board 1 is equipped with a first opto-isolation circuit 13, a second opto-isolation circuit 14, and an MCU 10 for outputting a low-level signal when the welding operation ends. The first opto-isolation circuit 13 includes an optocoupler U1, resistors R1, R2, and R3, a voltage VCC, and a power supply voltage 13a. One input terminal of the optocoupler U1, pin 3, is connected to one end of resistor R2, and the other end of resistor R2 is connected to the power supply voltage 13a. The other input terminal of the optocoupler U1, pin 4, is connected to one end of resistor R3, and the other end of resistor R3 is connected to the switch contact of the relay K1. One output terminal of the optocoupler U1, pin 1, is connected to the voltage VCC through resistor R1. One output terminal of the optocoupler U1, pin 1, is also connected to the MCU 10. The other output terminal of the optocoupler U1, pin 2, is grounded. The second opto-isolation circuit 14 includes an optocoupler U2, a resistor R4, and a diode D1. One input terminal of the optocoupler U2, pin 4, is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the MCU10. The other input terminal of the optocoupler U2, pin 3, is connected to the voltage VCC. One output terminal of the optocoupler U2, pin 1, is connected to the power supply voltage 13a and the negative terminal of the diode D1, respectively. The other output terminal of the optocoupler U2, pin 2, is connected to the coil of the relay K1 and the positive terminal of the diode D1, respectively.
[0019] The robot IO board 1 is also equipped with an output port 11 and an input port 12. The input port 12 is connected to the switch contacts of the resistor R3 and the relay K1, respectively. The output port 11 is connected to the positive terminal of the diode D1 and the coil of the relay K1, respectively.
[0020] An indicator light is connected in parallel across the coil of relay K1 to detect whether relay K1 is faulty.
[0021] When using industrial robots for welding operations, the equipment used includes a control cabinet, a laser, a wire feeder 4, and a welding robot. The robot I / O board 1, robot controller 2, relay K1, and wire feeder driver 5 in this wire-sticking alarm device for robotic laser welding are all housed within the control cabinet. The wire feeder driver 5 is connected to the robot I / O board 1 and also has a power cord 8 for connecting to an external power supply. During operation, the control cabinet is connected to the welding robot, laser, and wire feeder 4. The wire feeder 4 is connected to the wire feeder driver 5 and the wire guide rod 7. The robot controller 2 controls the wire feeder 4 to feed the welding wire, controls the laser to emit laser light to melt the welding wire, and controls the welding robot's end effector to perform the welding operation. When welding is finished, the robot controller 2 first shuts off the "wire feed" signal, causing the wire feeder driver 5 to stop working, thus immediately stopping the wire feeder 4. Then, it immediately activates the "wire retraction" signal, and the wire feeder 4 begins to retract the welding wire. During the wire retraction process, at the end of welding, or when the preset wire adhesion detection delay time is reached, the wire adhesion alarm device for robotic laser welding starts working. MCU10 and robot controller 2 communicate in real time through robot I / O board 1. Robot controller 2 sends a wire adhesion detection signal to MCU10. After receiving the signal, MCU10 sends a low-level signal to pin 4 of optocoupler U2, turning on the diode input side of optocoupler U2, thus turning on the transistor output side of optocoupler U2. This forms a circuit between the power supply voltage 13a, the transistor on the output side, the coil of relay K1, and ground. When the coil of relay K1 is energized, the indicator light illuminates, indicating normal circuit operation. If the switch contacts of relay K1 close at this time, and MCU10 detects a high-level signal, it indicates that the welding wire has successfully separated from the workpiece 9 and will not trigger an alarm. An alarm is triggered, but the robot continues to operate normally. If the welding wire adheres to the workpiece 9, a closed loop is formed by the power supply voltage 13a, the bidirectional diode of the optocoupler U1, the detection feedback line 6, the wire guide rod 7, the welding wire, the workpiece 9, and ground. The detection feedback line 6 will be at a low level, and pin 4 of the optocoupler U1 will be at a low level. The input side of the bidirectional diode of the optocoupler U1 will be turned on, thereby turning on the output side of the transistor of the optocoupler U1. The MCU10 will detect the low-level signal and send it to the robot controller 2. The robot controller 2 will then confirm that the robot end has contacted the workpiece 9, indicating that the welding wire is adhered to the workpiece 9. The robot controller 2 will trigger a wire adhesion alarm signal, control the wire feeder 4 to stop running, and control the teach pendant 3 to issue an alarm, promptly reminding the operator to handle the situation and avoid potential risks caused by the robot forcibly dragging the workpiece 9 due to the wire adhesion, thus improving the safety of equipment operation.
[0022] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.
Claims
1. A wire-sticking alarm device for robotic laser welding, comprising a robot I / O board (1) and a robot controller (2), characterized in that, The sticky wire alarm device also includes a relay K1. The robot IO board (1) is provided with a first opto-isolation circuit (13), a second opto-isolation circuit (14), and an MCU (10) for outputting a low-level signal at the end of the welding operation. The MCU (10) is connected to the input terminal of the second opto-isolation circuit (14). The coil of the relay K1 is connected in series between the output terminal of the second opto-isolation circuit (14) and ground. The input terminal of the first opto-isolation circuit (13) is connected to one switch contact of the relay K1. The other switch contact of the relay K1 is connected to the first switch contact of the first opto-isolation circuit (13). A detection feedback line (6) is connected to the wire guide rod (7) to obtain the signal of the welding wire sticking to the workpiece (9). The output of the first opto-isolation circuit (13) is connected to the MCU (10). The MCU (10) is used to confirm whether the welding wire sticks to the workpiece (9) according to the level signal output by the first opto-isolation circuit (13). The MCU (10) is connected to the robot controller (2) through the robot IO board (1). The robot controller (2) is also connected to a teach pendant (3) for alarming when the welding wire sticks to the workpiece (9).
2. The wire sticking alarm device for robotic laser welding according to claim 1, characterized in that, The first opto-isolation circuit (13) includes an optocoupler U1, resistors R1, R2, and R3, voltage VCC, and a power supply voltage (13a). One input terminal of the optocoupler U1 is connected to one end of resistor R2, and the other end of resistor R2 is connected to the power supply voltage (13a). The other input terminal of the optocoupler U1 is connected to one end of resistor R3, and the other end of resistor R3 is connected to the contact of relay K1. One output terminal of the optocoupler U1 is connected to voltage VCC through resistor R1. One output terminal of the optocoupler U1 is also connected to MCU (10), and the other output terminal of the optocoupler U1 is grounded.
3. The wire sticking alarm device for robotic laser welding according to claim 2, characterized in that, The second opto-isolation circuit (14) includes an optocoupler U2 and a resistor R4. One input terminal of the optocoupler U2 is connected to one end of the resistor R4, and the other end of the resistor R4 is connected to the MCU (10). The other input terminal of the optocoupler U2 is connected to the voltage VCC. One output terminal of the optocoupler U2 is connected to the power supply voltage (13a), and the other output terminal of the optocoupler U2 is connected to the coil of the relay K1.
4. The wire sticking alarm device for robotic laser welding according to claim 3, characterized in that, The second opto-isolation circuit (14) further includes a diode D1, the positive terminal of which is connected to the coil of the relay K1, and the negative terminal of which is connected to the power supply voltage (13a).
5. The wire sticking alarm device for robotic laser welding according to claim 4, characterized in that, The robot IO board (1) is also provided with an output port (11) and an input port (12). The input port (12) is connected to the switch contacts of the resistor R3 and the relay K1, respectively. The output port (11) is connected to the positive terminal of the diode D1 and the coil of the relay K1, respectively.
6. The wire sticking alarm device for robotic laser welding according to any one of claims 1 to 5, characterized in that, An indicator light for detecting whether relay K1 is faulty is connected in parallel across the two ends of the coil of relay K1.