Welding wire feeding device and method

Abstract

The invention provides a welding wire feeding device and method, and belongs to the technical field of welding equipment. The wire pushing motor is connected with the wire pushing wheel, and the wire pushing motor is set to apply constant torque to the wire pushing wheel during operation; the wire pushing mechanism, the buffer and the wire drawing mechanism are sequentially arranged in the wire feeding direction. The sensor is installed in the buffer, the switch control element is electrically connected with the wire pushing motor, and the sensor is electrically connected with the switch control element. The device has the beneficial effects that a wire feeding hose is omitted, so that the wire feeding resistance is greatly reduced, the wire feeding stability is improved in a constant-torque wire feeding mode, the length of a welding wire is judged by detecting the position of the welding wire through a sensor, and a control signal is sent to a switch control element; the switch control element controls the wire pushing motor to start and stop at a high speed according to a control signal of the sensor, so that the pulse type wire pushing and drawing effect is achieved, and the difficulty of double-motor synchronous control is greatly reduced through the high-speed dynamic response mode of the wire pushing motor.

Description

Technical Field

[0001] The invention belongs to the technical field of welding equipment and relates to a welding wire feeding device and method. Background Art

[0002] MIG Metal Inert Gas Welding (MIG Metal Inert Gas Welding) is an inert gas (Ar or He) shielded arc welding method using solid wire, which is widely used in aluminum alloy welding. During welding operations, a high-speed servo motor is required to pull the welding wire at high speed, thereby feeding the welding wire to the conductive nozzle of the welding gun. During the wire feeding process, the welding wire needs to be fed and drawn at high speed. The stability and accuracy of the welding wire during wire feeding are important factors that determine the quality of the welding process. Among them, unstable wire feeding will directly lead to unstable welding arc, resulting in uneven weld formation, incomplete welding and other welding defects; low wire feeding accuracy will lead to a large number of short circuits in welding, and increase spatter during welding, which is prone to burning of the conductive nozzle.

[0003] During aluminum alloy welding, due to the low strength and smooth surface of aluminum welding wire, excessive pressure on the wire feed roll of the wire drawing motor can easily cause the wire to deform. Too little pressure results in insufficient friction, making it impossible to overcome the resistance within the wire feed hose. Therefore, aluminum wire feeding requires low resistance and stable wire drawing motion. However, in actual applications, the wire feed hose is long and often bent at varying degrees. Especially during high-speed drawing, the contact area between the wire and the wire feed hose increases, resulting in a significant increase in resistance. The friction between the wire feed roll and the wire is insufficient, making it difficult to control the motor to ensure wire feeding stability.

[0004] Based on the above reasons, the following two methods are commonly used for wire feeding:

[0005] Method 1: Add a wire pushing motor between the wire feeding hose and the barreled welding wire, so that the wire pushing motor and the wire drawing motor are located at both ends of the wire feeding hose respectively. The wire pushing motor pushes the welding wire into the wire feeding hose, and the wire drawing motor draws the welding wire out of the wire feeding hose. Although this method can solve the problem of excessive resistance of the welding wire during high-speed wire pushing and drawing, the bending condition of the wire feeding hose changes continuously in actual use, resulting in irregular changes in the friction force of the welding wire, unstable wire feeding, and difficulty in drawing wire.

[0006] Method 2: Add a buffer in the middle of the wire feeding hose, and add a wire pushing motor between the wire feeding hose and the barreled welding wire. The buffer can store a certain amount of welding wire. The wire pushing motor pushes the welding wire into the buffer, and the wire drawing motor draws the welding wire out of the buffer. This method adopts a constant torque design. The buffer needs to constrain the welding wire through the wire feeding hose. The sensor detects the position of the wire feeding hose to control the speed of the wire pushing motor so that the wire pushing speed is the same as the wire drawing speed, thereby ensuring the same degree of bending of the welding wire. This means that the wire pushing motor and the wire drawing motor need to maintain absolute synchronization, which places high demands on hardware such as motors, controllers, and speed sensors, requires a large investment, and is difficult to control in practice. It often fails to achieve the ideal control effect. Moreover, in this solution, the welding wire will be subjected to greater friction in the wire feeding hose, which cannot meet the requirements of low-resistance wire feeding.

[0007] The current wire feeding device has limitations in practical applications, and it is difficult to simultaneously meet the comprehensive requirements of low wire feeding resistance, constant torque output, and low synchronization requirements for the wire pushing motor and the wire drawing motor. Summary of the Invention

[0008] The purpose of the present invention is to address the above-mentioned problems existing in the prior art and to propose a welding wire feeding device and method.

[0009] The object of the present invention can be achieved by the following technical solutions: A welding wire feeding device comprising:

[0010] A spinning mechanism, comprising a spinning motor and a spinning wheel, wherein the spinning motor is connected to the spinning wheel;

[0011] A wire pushing mechanism, the wire pushing mechanism comprising a wire pushing motor and a wire pushing wheel, the wire pushing motor being connected to the wire pushing wheel, and the wire pushing motor being configured to apply a constant torque to the wire pushing wheel during operation;

[0012] The buffer, the wire pushing mechanism, the buffer and the wire drawing mechanism are sequentially arranged along the wire feeding direction;

[0013] A control mechanism, the control mechanism comprising a sensor and a switch control element, the sensor being installed in the buffer, the switch control element being electrically connected to the wire pushing motor, and the sensor being electrically connected to the switch control element;

[0014] The sensor is configured to detect the length of the welding wire in the buffer, and to control the wire pushing motor to run or stop through the switch control element according to the length of the welding wire.

[0015] Preferably, the wire pushing mechanism further includes an electromagnetic coupler, and the wire pushing motor is connected to the wire pushing wheel via the electromagnetic coupler.

[0016] Preferably, the electromagnetic coupler includes an input rotor, an output rotor and a gap adjustment element. The input rotor and the output rotor are arranged correspondingly and a gap is reserved between the two. Part of the gap adjustment element is inserted into the gap. The insertion depth of the gap adjustment element determines the size of the gap and thus determines the size of the torque transmitted by the electromagnetic coupler.

[0017] Preferably, the switch control element is configured as an IGBT module.

[0018] Preferably, a buffer cavity is provided inside the buffer, the sensor is provided in the buffer cavity, the inlet and outlet of the buffer cavity are not collinear so that the welding wire passing through the buffer cavity is bent, the length of the welding wire in the buffer cavity determines the position of the welding wire, and the sensor is configured to detect the length of the welding wire according to the position of the welding wire in the buffer cavity.

[0019] Preferably, the buffer cavity is configured as a crescent-shaped structure, the inner edge of the buffer cavity is configured as a lower limit boundary of the welding wire, the outer edge of the buffer cavity is configured as an upper limit boundary of the welding wire, the arc length of the upper limit boundary of the welding wire is greater than the arc length of the lower limit boundary of the welding wire, and a start-stop critical position is defined in the buffer cavity, the area between the upper limit boundary of the welding wire and the start-stop critical position is a stop area, and the area between the lower limit boundary of the welding wire and the start-stop critical position is an operating area;

[0020] When the length of the welding wire in the buffer chamber is greater than a threshold value, the welding wire is in the stop area; when the length of the welding wire in the buffer chamber is less than a threshold value, the welding wire is in the operating area; the sensor is configured to output a corresponding signal to the switch control element according to whether the welding wire is in the stop area or the operating area, and the switch control element controls the wire pushing motor to stop or run according to the corresponding signal.

[0021] Preferably, the buffer includes a base and a slot cover, the base is provided with a buffer slot, and the slot cover seals the opening of the buffer slot to form the buffer cavity.

[0022] Preferably, the sensor is configured as a capacitive proximity switch, the sensing area of ​​the capacitive proximity switch is located in the shutdown area or the operating area, and the slot cover and the base are both configured as insulating parts.

[0023] Preferably, the buffer is provided with an inlet connector and an outlet connector, and the inlet connector and the outlet connector are respectively located at the inlet and outlet of the buffer chamber, the inlet connector and the wire pushing mechanism are connected through a first wire feeding tube, and the outlet connector and the wire drawing mechanism are connected through a second wire feeding tube.

[0024] A method for feeding welding wire, using the welding wire feeding device to feed the welding wire to a welding machine, comprises the following steps:

[0025] S1: First, let the welding wire pass through the wire pushing mechanism, buffer and wire drawing mechanism in sequence. The wire drawing mechanism sends the welding wire to the conductive nozzle of the welding gun head;

[0026] S2: Start the wire feeding device, and the wire pushing motor and wire drawing motor are running. The wire pushing motor pushes the welding wire into the buffer chamber of the buffer with a constant torque through the wire pushing wheel. A certain amount of welding wire is stored in the buffer chamber. The wire drawing motor draws the welding wire out of the buffer chamber through the wire drawing wheel and continuously feeds it to the contact nozzle.

[0027] S3: The sensor senses the length of the welding wire in the buffer chamber through the position of the welding wire in the buffer chamber, and the sensor controls the wire pushing motor to feed the wire in a pulsed manner through the switch control element; wherein, when the length of the welding wire in the buffer chamber is greater than the threshold value, the welding wire in the buffer chamber deviates to the shutdown area, and the sensor detects the capacitance change and immediately controls the wire pushing motor to stop through the switch control element, thereby stopping feeding the welding wire into the buffer chamber; when the length of the welding wire in the buffer chamber is less than the threshold value, the welding wire in the buffer chamber deviates to the running area, and the sensor detects the capacitance change and immediately controls the wire pushing motor to run through the switch control element, thereby feeding the welding wire into the buffer chamber.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The wire feeding hose is eliminated, thereby greatly reducing the wire feeding resistance. The wire feeding stability is improved by constant torque wire feeding. The sensor is used to detect the wire position to determine the wire length and send a control signal to the switch control element. The switch control element controls the high-speed start and stop of the wire pushing motor according to the control signal of the sensor, thereby achieving a pulsed wire pushing and pulling effect. In addition, the difficulty of dual-motor synchronous control is greatly reduced by the high-speed dynamic response of the wire pushing motor.

[0030] 2. Pulse wire pushing is a continuous cycle of pushing and stopping. The interval between two adjacent wire pushing is extremely short. The switch control element controls the timing of starting and stopping the wire pushing motor according to the signal from the sensor. This method mainly relies on the precise detection of the sensor and the high-speed start and stop control of the motor by the switch control element. The wire pushing motor does not need to be strictly synchronized with the wire drawing motor. The wire pushing motor responds to the wire drawing speed of the wire drawing motor through high-speed start and stop in a high-speed dynamic pulse wire pushing manner.

[0031] 3. This device completely eliminates the need for a wire feed hose. Instead, the wire pusher pushes the wire directly into the buffer, where it is then drawn out by the wire drawer and fed to the contact tip of the welding gun. This eliminates frictional resistance between the wire and the hose, achieving low-resistance wire feeding. Even at a high-speed wire feed of 14 m / min, the resistance is less than 3 N, enabling this device to meet the high-speed, low-resistance wire feeding requirements of the MIG welding process.

[0032] 4. The wire-pushing motor uses a constant torque mode. Regardless of the resistance encountered during wire feeding (as long as it's within the motor's capabilities), the torque output by the wire-pushing motor remains constant. This ensures that the wire can be pushed out stably, without a sudden drop in thrust due to slight resistance. This meets the stability and precision requirements of high-speed wire feeding and ensures optimal MIG welding results. Furthermore, the wire-pushing motor maintains a stable buffer length by starting and stopping at high speed. Even if there's a speed difference between the wire-pushing motor and the wire-drawing motor, the high-speed starting and stopping of the wire-pushing motor can keep the wire-pushing and wire-drawing speeds consistent.

[0033] 5. The capacitive proximity switch does not require contact with the welding wire during detection, meaning there is no friction between the wire and the capacitive proximity switch, which is crucial for high-speed, low-resistance wire feeding. Furthermore, the base and slot cover can be made of wear-resistant, smooth materials, ensuring minimal friction even when the wire and buffer come into contact. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic structural diagram of the wire feeding device of the present invention.

[0035] Figure 2 Schematic diagram of the structure of the buffer of the present invention.

[0036] Figure 3 This is a structural exploded view of the buffer of the present invention.

[0037] Figure 4 Schematic diagram of the buffer of the present invention.

[0038] Figure 5 Schematic diagram of the electromagnetic coupler and IGBT module of the present invention.

[0039] Figure 6 This is a schematic diagram of the control principle of the high-speed pulse start and stop of the wire pushing motor of the present invention.

[0040] In the figure, 100, wire drawing motor; 110, wire drawing wheel; 200, wire pushing motor; 210, wire pushing wheel; 300, buffer; 310, buffer chamber; 311, upper limit boundary of welding wire; 312, lower limit boundary of welding wire; 313, start-stop critical position; 314, shutdown area; 315, operating area; 320, base; 321, buffer tank; 330, tank cover; 340, inlet connector; 350, outlet connector; 360, first wire feed guide tube; 370, second wire feed guide tube; 400, capacitive proximity switch; 500, IGBT module; 600, electromagnetic coupler; 700, conductive nozzle. DETAILED DESCRIPTION

[0041] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0042] like Figures 1 to 6 As shown, a welding wire feeding device includes:

[0043] The wire drawing mechanism includes a wire drawing motor 100 and a wire drawing wheel 110, and the wire drawing motor 100 is connected to the wire drawing wheel 110;

[0044] The wire pushing mechanism includes a wire pushing motor 200 and a wire pushing wheel 210. The wire pushing motor 200 is connected to the wire pushing wheel 210. The wire pushing motor 200 is configured to apply a constant torque to the wire pushing wheel 210 during operation.

[0045] The buffer 300, the wire pushing mechanism, the buffer 300 and the wire drawing mechanism are sequentially arranged along the wire feeding direction;

[0046] The control mechanism includes a sensor and a switch control element. The sensor is installed in the buffer 300. The switch control element is electrically connected to the wire pushing motor 200. The sensor is electrically connected to the switch control element.

[0047] The sensor is configured to detect the length of the welding wire in the buffer 300 and control the wire pushing motor 200 to run or stop according to the length of the welding wire through the switch control element.

[0048] This device adopts a pulsed constant torque wire pushing method combined with active pulling to convey welding wire to the conductive nozzle 700 of the welding machine, wherein a buffer 300 for buffering and storing welding wire is arranged between the wire drawing mechanism and the wire pushing mechanism. The sensor in the buffer 300 can feedback the length of the welding wire to the switch control element. The switch control element operates or stops the wire pushing motor 200 according to the length of the welding wire. Therefore, in actual operation, the wire pushing motor 200 is in a high-speed start-stop state. When the length of the welding wire in the buffer 300 is too long, the wire pushing motor 200 stops. When the length of the welding wire in the buffer 300 is too short, the wire pushing motor 200 operates.

[0049] The basic principle of high-speed wire feeding of this device is: the wire pushing motor 200 applies a constant torque to the wire pushing wheel 210, thereby pushing the welding wire into the buffer 300. A certain length of welding wire is stored in the buffer 300. The wire drawing wheel 110 driven by the wire drawing motor 100 actively draws the welding wire out of the buffer 300 at a uniform speed and supplies it to the welding gun for welding.

[0050] Based on the above basic principle of wire feeding, the speed of the wire pushing motor 200 needs to be strictly consistent with the speed of the wire drawing motor 100. If the speeds of the two motors are inconsistent, the stability and accuracy of wire feeding will be seriously affected, and it will easily cause the welding wire to bend, entangle, break or difficulty in drawing. In order to solve the problem of difficult synchronous control of dual motors, the length of the welding wire in the buffer 300 is detected in real time in this device. Once the welding wire length exceeds the threshold, the switch control element controls the wire pushing motor 200 to stop, so that the wire drawing motor 100 can promptly draw out the welding wire in the buffer 300. When the welding wire length in the buffer 300 is lower than the threshold, the switch control element controls the wire pushing motor 200 to run, and the welding wire is continuously pushed into the buffer 300. Since the switch control element controls the start and stop of the wire pushing motor 200 in a very short time according to the signal of the sensor, the length of the welding wire in the buffer 300 is always kept near the threshold. During the whole process, the wire pushing motor 200 is continuously started and stopped at high speed to achieve the effect of pulsed wire pushing.

[0051] In simple terms, pulsed wire pushing is a continuous cycle of pushing and stopping, with the interval between two adjacent wire pushings being extremely short. The switch control element controls the timing of starting and stopping the wire pushing motor 200 according to the signal from the sensor. This method mainly relies on the precise detection of the sensor and the high-speed start and stop control of the motor by the switch control element. The wire pushing motor 200 does not need to be strictly synchronized with the wire drawing motor 100. The wire pushing motor 200 responds to the wire drawing speed of the wire drawing motor 100 by high-speed start and stop in a high-speed dynamic pulse wire pushing manner.

[0052] The switch control element is preferably an IGBT module 500, which can provide a pulse power supply to control the high-speed start and stop of the wire pushing motor 200. In actual application, the start and stop time of the wire pushing motor 200 controlled by the IGBT module 500 is within 10 milliseconds. The sensor can determine whether the length of the welding wire exceeds the threshold by detecting the position of the welding wire. Its detection signal response characteristics are high, and the response time is less than 50 milliseconds. It can adapt to the high-speed wire feeding environment, and the sensor is very sensitive. It can detect the tiny position of the welding wire in the buffer 300, so that the switch control element can control the buffer length of the welding wire under high-speed wire feeding, thereby achieving the purpose of high-speed push-pull wire feeding by dual motors. It should be pointed out that since the device is directly driven entirely by hardware circuits, it has high reliability and fast response characteristics, a simple structure, and does not need to rely on complex dual-motor control algorithms.

[0053] This device completely eliminates the need for a wire feed hose. Instead, the wire pusher pushes the wire directly into the buffer 300, where it is then withdrawn by the wire extraction mechanism and fed to the welding gun's contact tip 700. This eliminates frictional resistance between the wire and the hose, achieving low-resistance wire feeding. Even at a high-speed wire feed rate of 14 m / min, the resistance is reduced to less than 3 N, enabling this device to meet the high-speed, low-resistance wire feeding requirements of the MIG welding process.

[0054] Moreover, the wire pushing motor 200 of the present device adopts a constant torque mode. No matter what kind of resistance the welding wire encounters during the pushing process (as long as it is within the motor's capacity), the torque output by the wire pushing motor 200 always remains constant. This ensures that the welding wire can be pushed out stably, and the thrust will not drop suddenly due to slight resistance, thereby meeting the stability and precision requirements of high-speed wire feeding and ensuring the welding effect of MIG welding. In addition, the wire pushing motor 200 ensures the stability of the buffer length of the welding wire by high-speed start and stop. Even if there is a speed difference between the wire pushing motor 200 and the wire drawing motor 100, the wire pushing speed can be kept consistent with the wire drawing speed by the high-speed start and stop of the wire pushing motor 200.

[0055] like Figure 1 、 Figure 5 As shown, on the basis of the above embodiment, the wire pushing mechanism further includes an electromagnetic coupler 600 , and the wire pushing motor 200 is connected to the wire pushing wheel 210 via the electromagnetic coupler 600 .

[0056] The electromagnetic coupler 600 is an element that transmits torque based on a magnetic field (electromagnetic force) or eddy current effect. It is itself a physical constant torque transmission element that can transmit the torque of the wire pushing motor 200 to the wire pushing wheel 210 in a non-contact manner. The electromagnetic coupler 600 has the characteristic of constant torque output. As long as the output torque of the electromagnetic coupler 600 is set, the torque output by the electromagnetic coupler 600 is a constant value.

[0057] Based on the above embodiment, the electromagnetic coupler 600 includes an input rotor, an output rotor and a gap adjustment element. The input rotor and the output rotor are arranged correspondingly and a gap is reserved between the two. Part of the gap adjustment element is inserted into the gap. The insertion depth of the gap adjustment element determines the size of the gap and thus determines the size of the torque transmitted by the electromagnetic coupler 600.

[0058] Electromagnetic coupler 600 is an existing torque transmission element. Essentially all electromagnetic couplers 600 have the function of adjusting output torque. Once the output torque is set, the output rotor of electromagnetic coupler 600 can only output the set torque. The gap adjustment element can be configured as a ramp block that can be inserted between the input and output rotors to adjust the gap between them. The set torque of electromagnetic coupler 600 is determined by the size of this gap, and the torque can be varied by adjusting the gap.

[0059] like Figures 1 to 6 As shown, on the basis of the above embodiment, a buffer cavity 310 is provided inside the buffer 300, and a sensor is provided in the buffer cavity 310. The inlet and outlet of the buffer cavity 310 are not collinear, so that the welding wire passing through the buffer cavity 310 is bent. The length of the welding wire in the buffer cavity 310 determines the position of the welding wire, and the sensor is configured to detect the length of the welding wire according to the position of the welding wire in the buffer cavity 310.

[0060] On the basis of the above embodiment, the buffer chamber 310 is set to a crescent-shaped structure, the inner edge of the buffer chamber 310 is set to the lower limit boundary 312 of the welding wire, and the outer edge of the buffer chamber 310 is set to the upper limit boundary 311 of the welding wire. The arc length of the upper limit boundary 311 of the welding wire is greater than the arc length of the lower limit boundary 312 of the welding wire. There is a start-stop critical position 313 in the buffer chamber 310, the area between the upper limit boundary 311 of the welding wire and the start-stop critical position 313 is the stop area 314, and the area between the lower limit boundary 312 of the welding wire and the start-stop critical position 313 is the operation area 315; when the length of the welding wire in the buffer chamber 310 is greater than the threshold, the welding wire is in the stop area 314; when the length of the welding wire in the buffer chamber 310 is less than the threshold, the welding wire is in the operation area 315; the sensor is set to output a corresponding signal to the switch control element according to whether the welding wire is in the stop area 314 or the operation area 315, and the switch control element controls the wire pushing motor 200 to stop or run according to the corresponding signal.

[0061] Buffer chamber 310 is designed in a crescent-shaped structure, with its entrance and exit not aligned. Due to the bendability of the welding wire, the portion of the wire passing through buffer chamber 310 inevitably forms a curved shape (similar to an arc). As the length of the welding wire within buffer chamber 310 increases, the length of the arc increases, while the ends of the arc remain unchanged, causing the welding wire to approach the outer edge of buffer chamber 310 (wire upper limit 311). As the length of the welding wire within buffer chamber 310 decreases, the arc length decreases, causing the welding wire to approach the inner edge of buffer chamber 310 (wire lower limit 312). When the length of the welding wire within buffer chamber 310 reaches a threshold, the welding wire is precisely at the start / stop critical position 313. Therefore, the specific position of the welding wire within buffer chamber 310 directly corresponds to its length (reserve capacity). The sensor, designed as a proximity switch, detects the specific position of the welding wire and determines whether the wire length is greater than or less than the threshold.

[0062] When the sensor detects that the welding wire is in the stop area 314, it means that the buffer length of the welding wire exceeds the threshold, the sensor outputs an NPN disconnection signal, and the IGBT module 500 controls the wire pushing motor 200 to stop; when the sensor detects that the welding wire is not in the stop area 314, then the welding wire must be in the operating area 315, indicating that the length of the welding wire is less than the threshold, the sensor outputs an NPN connection signal, and the IGBT module 500 controls the wire pushing motor 200 to operate.

[0063] During actual operation, the position of the welding wire in the buffer chamber 310 changes dynamically, shifting back and forth between the stop area 314 and the operation area 315. The sensor controls the high-speed start and stop of the motor in the form of a pulse signal through the IGBT module 500, so that the length of the welding wire in the buffer chamber 310 is maintained within a smaller cache margin range.

[0064] The detection logic of this method is clear and simple, and the response speed is fast. Detection and judgment are based on physical position changes and do not rely on complex calculations. The sensor directly outputs switching signals, which facilitates rapid response and avoids noise interference or calculation errors that may occur by accurately measuring the length and then making logical judgments.

[0065] It should also be noted that the control mechanism, in conjunction with the buffer 300, uses geometric design to amplify the positional variation (arc length difference) of the welding wire length, facilitating the sensor's capture of key state changes. This, combined with the fast start-stop element (IGBT module 500), accommodates high-speed wire feeding. This position triggering method is less expensive than installing a precise linear displacement sensor (such as an encoder or wire gauge) and performing digital conversion and judgment.

[0066] like Figures 1 to 4As shown, based on the above embodiment, the buffer 300 includes a base 320 and a slot cover 330 . The base 320 is provided with a buffer slot 321 . The slot cover 330 seals the opening of the buffer slot 321 to form a buffer cavity 310 .

[0067] Based on the above embodiment, the sensor is configured as a capacitive proximity switch 400 , the sensing area of ​​the capacitive proximity switch 400 is located in the stop area 314 or the operation area 315 , and the slot cover 330 and the base 320 are both configured as insulating parts.

[0068] The sensor uses a non-contact capacitive proximity switch 400, which includes an electrode (sensing surface) and an associated oscillation circuit. When any object (medium) that can affect the electric field appears near the electrode, a capacitor is formed between the object and the electrode. This external capacitor will be connected to the high-frequency oscillation circuit inside the switch, thereby changing the capacitance value of the circuit. When the changed capacitance value reaches a preset detection threshold, the switch's electronic circuit will generate an output state change.

[0069] In this example, as the welding wire enters and leaves the sensing area, the capacitance of the capacitive proximity switch 400 increases or decreases significantly, outputting a corresponding signal to detect the welding wire's position. Capacitive proximity switch 400 is highly sensitive and has an extremely fast response, making it suitable for high-speed detection.

[0070] The capacitive proximity switch 400 directly detects the position of the welding wire. Its detection signal response characteristics are high, and the response time is less than 50 milliseconds. It can adapt to the high-speed wire feeding environment. The capacitive proximity switch 400 cooperates with the IGBT module 500 to achieve the purpose of controlling the welding wire buffer length within a predetermined range under high-speed wire feeding.

[0071] It's important to note that the capacitive proximity switch 400 doesn't need to come into contact with the welding wire during detection. This means there's no friction between the welding wire and the capacitive proximity switch 400, which is crucial for high-speed, low-resistance wire feeding. Furthermore, the base 320 and slot cover 330 can be made of a smooth, wear-resistant material, ensuring that even if contact occurs, there's no significant friction between the welding wire and the buffer 300.

[0072] Furthermore, since the slot cover 330 and the base 320 are both insulating parts and the welding wire is an aluminum metal part, this design can shield interference, allowing the capacitive proximity switch 400 to more accurately detect the position of the welding wire.

[0073] like Figures 1 to 4As shown, on the basis of the above embodiment, the buffer 300 is provided with an inlet connector 340 and an outlet connector 350, which are respectively located at the inlet and outlet of the buffer chamber 310, and the inlet connector 340 is connected to the wire pushing mechanism through a first wire feeding tube 360, and the outlet connector 350 is connected to the wire drawing mechanism through a second wire feeding tube 370.

[0074] The first wire feed duct 360 and the second wire feed duct 370 are designed as rigid tubes, which mainly play a guiding role. Different from traditional hoses, the welding wire will not or only has limited contact with the wire feed duct, so no large friction will be generated.

[0075] like Figures 1 to 6 As shown, based on the above embodiment, a wire feeding method of welding wire, using a wire feeding device to feed the welding wire to a welding machine, includes the following steps:

[0076] S1: First, the welding wire passes through the wire pushing mechanism, the buffer 300 and the wire drawing mechanism in sequence, and the wire drawing mechanism sends the welding wire to the conductive nozzle 700 of the welding gun head;

[0077] S2: The wire feeding device is started, and the wire pushing motor 200 and the wire drawing motor 100 are in operation. The wire pushing motor 200 pushes the welding wire into the buffer chamber 310 of the buffer 300 at a constant torque via the wire pushing wheel 210. A certain amount of welding wire is stored in the buffer chamber 310. The wire drawing motor 100 draws the welding wire from the buffer chamber 310 via the wire drawing wheel 110 and continuously feeds the welding wire to the contact tip 700.

[0078] S3: The sensor senses the length of the welding wire in the buffer chamber 310 through the position of the welding wire in the buffer chamber 310, and the sensor controls the wire pushing motor 200 to feed the wire in a pulsed manner through the switch control element; wherein, when the length of the welding wire in the buffer chamber 310 is greater than the threshold value, the welding wire in the buffer chamber 310 deviates to the stop area 314, and the sensor detects the capacitance change and immediately controls the wire pushing motor 200 to stop through the switch control element, thereby stopping the feeding of the welding wire into the buffer chamber 310; when the length of the welding wire in the buffer chamber 310 is less than the threshold value, the welding wire in the buffer chamber 310 deviates to the operating area 315, and the sensor detects the capacitance change and immediately controls the wire pushing motor 200 to operate through the switch control element, thereby feeding the welding wire into the buffer chamber 310.

[0079] This method mainly solves the core problem of dual-motor synchronization and resistance control in high-speed, low-resistance wire feeding in the MIG welding (inert gas shielded welding) process. Specifically, it achieves high-speed (such as 14 meters / minute) welding wire feeding, ensures low wire feeding resistance (resistance less than 3N), and solves the problems of high friction of traditional wire feeding hoses and complex and difficult dual-motor speed synchronization control, ensuring wire feeding stability and accuracy, and avoiding wire bending, entanglement, breakage or wire drawing difficulties.

[0080] The wire pushing mechanism cooperates with the electromagnetic coupler 600 to achieve the purpose of constant torque output. When the wire pushing motor 200 operates, the electromagnetic coupler 600 applies constant torque to the wire pushing wheel 210, the wire pulling mechanism pulls the welding wire from the buffer 300 to the welding gun conducting nozzle 700. Among them, the wire pushing motor 200 is not continuously and uniformly operated, but is started and stopped at high speed (pulse operation) under the command of the switch control element. When the wire pushing motor 200 operates each time, the wire pushing wheel 210 pushes the welding wire into the buffer 300 under the action of constant torque. The buffer 300 is located between the wire pushing mechanism and the wire pulling mechanism, and serves as a buffer area for the welding wire. The buffer cavity 310 receives the pulse type pushed welding wire, and supplies the uniformly pulled wire pulling mechanism. The change of the internal welding wire reserve amount is the key signal to control the start and stop of the wire pushing. The capacitive proximity switch 400 directly judges whether the welding wire is in the shutdown area 314 or the running area 315 according to the position of the welding wire. The IGBT module 500 receives the switch signal of the sensor and controls the high-speed start and stop of the wire pushing motor 200.

[0081] It should be noted that all directional indications, such as up, down, left, right, front, back, etc., in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture, and if the specific posture changes, the directional indications will also change accordingly.

[0082] In addition, the descriptions such as "first", "second", "one" and the like in the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" can be explicitly or implicitly included at least one of the features.

[0083] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixation" and the like should be understood in a broad sense, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be direct connection, or indirect connection through intermediate medium; can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise explicitly limited.

[0084] In addition, the technical solutions of each embodiment of the present application can be combined with each other, but it must be based on the realization of the ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor within the scope of protection required by the present application.

Claims

1. A welding wire feeding device, characterized in that: include: A spinning mechanism, the spinning mechanism comprising a spinning motor (100) and a spinning wheel (110), the spinning motor (100) being connected to the spinning wheel (110); A wire pushing mechanism, comprising a wire pushing motor (200) and a wire pushing wheel (210), wherein the wire pushing motor (200) is connected to the wire pushing wheel (210), and the wire pushing motor (200) is configured to apply a constant torque to the wire pushing wheel (210) during operation; A buffer (300), the wire pushing mechanism, the buffer (300) and the wire drawing mechanism are sequentially arranged along the wire feeding direction; A control mechanism, the control mechanism comprising a sensor and a switch control element, the sensor being installed in the buffer (300), the switch control element being electrically connected to the wire pushing motor (200), and the sensor being electrically connected to the switch control element; The sensor is configured to detect the length of the welding wire in the buffer (300), and to control the wire pushing motor (200) to operate or stop according to the length of the welding wire through the switch control element.

2. A welding wire feeding device according to claim 1, characterized in that: The wire pushing mechanism further comprises an electromagnetic coupler (600), and the wire pushing motor (200) is connected to the wire pushing wheel (210) via the electromagnetic coupler (600).

3. A welding wire feeding device according to claim 2, characterized in that: The electromagnetic coupler (600) comprises an input rotor, an output rotor, and a gap adjustment element. The input rotor and the output rotor are arranged correspondingly with a gap reserved therebetween. A portion of the gap adjustment element is inserted into the gap. The insertion depth of the gap adjustment element determines the size of the gap and thus determines the size of the torque transmitted by the electromagnetic coupler (600).

4. A welding wire feeding device according to claim 1, characterized in that: The switch control element is configured as an IGBT module (500).

5. A welding wire feeding device according to claim 1, characterized in that: A buffer chamber (310) is provided inside the buffer (300), the sensor is provided in the buffer chamber (310), the inlet and outlet of the buffer chamber (310) are not collinear, so that the welding wire passing through the buffer chamber (310) is bent, the length of the welding wire in the buffer chamber (310) determines the position of the welding wire, and the sensor is configured to detect the length of the welding wire according to the position of the welding wire in the buffer chamber (310).

6. A welding wire feeding device according to claim 5, characterized in that: The buffer cavity (310) is configured as a crescent-shaped structure, the inner edge of the buffer cavity (310) is configured as a welding wire lower limit boundary (312), the outer edge of the buffer cavity (310) is configured as a welding wire upper limit boundary (311), the arc length of the welding wire upper limit boundary (311) is greater than the arc length of the welding wire lower limit boundary (312), a start-stop critical position (313) is provided in the buffer cavity (310), the area between the welding wire upper limit boundary (311) and the start-stop critical position (313) is a stop area (314), and the area between the welding wire lower limit boundary (312) and the start-stop critical position (313) is an operating area (315); When the length of the welding wire in the buffer chamber (310) is greater than a threshold value, the welding wire is in the stop area (314); when the length of the welding wire in the buffer chamber (310) is less than a threshold value, the welding wire is in the operating area (315); the sensor is configured to output a corresponding signal to the switch control element according to whether the welding wire is in the stop area (314) or the operating area (315), and the switch control element controls the wire pushing motor (200) to stop or operate according to the corresponding signal.

7. A welding wire feeding device according to claim 6, characterized in that: The buffer (300) comprises a base (320) and a slot cover (330), wherein the base (320) is provided with a buffer slot (321), and the slot cover (330) seals the opening of the buffer slot (321) to form the buffer cavity (310).

8. A welding wire feeding device according to claim 7, characterized in that: The sensor is configured as a capacitive proximity switch (400), the sensing area of ​​the capacitive proximity switch (400) is located in the shutdown area (314) or the operation area (315), and the slot cover (330) and the base (320) are both configured as insulating parts.

9. A welding wire feeding device according to claim 5, characterized in that: The buffer (300) is provided with an inlet connector (340) and an outlet connector (350), wherein the inlet connector (340) and the outlet connector (350) are respectively located at the inlet and outlet of the buffer chamber (310), the inlet connector (340) is connected to the wire pushing mechanism via a first wire feeding duct (360), and the outlet connector (350) is connected to the wire drawing mechanism via a second wire feeding duct (370).

10. A method for feeding welding wire, comprising feeding the welding wire to a welding machine using the welding wire feeding device according to any one of claims 1 to 9, wherein: The steps are as follows: S1: First, the welding wire is passed through the wire pushing mechanism, the buffer (300) and the wire drawing mechanism in sequence, and the wire drawing mechanism sends the welding wire to the conductive nozzle (700) of the welding gun head; S2: The wire feeding device is started, and the wire pushing motor (200) and the wire drawing motor (100) are in operation. The wire pushing motor (200) pushes the welding wire into the buffer chamber (310) of the buffer (300) at a constant torque through the wire pushing wheel (210). A certain amount of welding wire is stored in the buffer chamber (310). The wire drawing motor (100) draws the welding wire from the buffer chamber (310) through the wire drawing wheel (110) and continuously feeds the welding wire to the conductive nozzle (700). S3: The sensor senses the length of the welding wire in the buffer chamber (310) through the position of the welding wire in the buffer chamber (310), and the sensor controls the wire pushing motor (200) to feed the wire in a pulsed manner through a switch control element; wherein, when the length of the welding wire in the buffer chamber (310) is greater than a threshold value, the welding wire in the buffer chamber (310) deviates to a stop region (314), and the sensor immediately controls the wire pushing motor (200) to stop through the switch control element upon detecting a change in capacitance, thereby stopping feeding the welding wire into the buffer chamber (310); when the length of the welding wire in the buffer chamber (310) is less than a threshold value, the welding wire in the buffer chamber (310) deviates to an operating region (315), and the sensor immediately controls the wire pushing motor (200) to operate through the switch control element upon detecting a change in capacitance, thereby feeding the welding wire into the buffer chamber (310).

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