A welding torch self-calibration device

Abstract

This invention provides a welding torch self-calibration device, characterized by comprising a calibration component and a welding torch component; the calibration component includes a reference calibration column, two symmetrically arranged measuring units, a guide unit, a transmission detection unit, and a rotation unit working in concert: the reference calibration column is located at the center of the calibration component to provide a calibration reference; when the measuring units move, they provide displacement signals through the transmission detection unit; the rotation unit drives the entire calibration component to rotate around the central axis of the reference calibration column; simultaneously, a Z-axis displacement sensor is configured to detect the welding torch's Z-axis positional offset; the end of the welding torch component is provided with a positioning contact and a welding contact point; the positioning contact is used for contact positioning with the two measuring units of the calibration component; the welding contact point is used for subsequent welding operations. This device, through structural integration and algorithm optimization, possesses the following core technical advantages: First, it adopts a collaborative design of mechanical structure and sensors to achieve automated calibration of the X / Y / Z axes, significantly improving calibration efficiency.

Description

Technical Field

[0001] This invention relates to the technical field of automated equipment, and in particular to a welding torch self-calibration device. Background Technology

[0002] In past applications, pressure resistance welding of arrayed thin-walled tubes and kits was typically performed manually. This method was not only inefficient, but also made it difficult to guarantee the quality of the welds.

[0003] To address the issue of low efficiency in manual welding, automated welding robots can be used. However, because the welding torch cannot be accurately and automatically centered and zeroed, it can cause the torch to become misaligned when welding arrays, thus affecting welding quality and even preventing subsequent welding operations from being carried out.

[0004] Existing technology, CN202311844658.6, describes a method, device, storage medium, and electronic device for calibrating the deviation of a welding torch end. It uses an arc electrical signal + laser image coordinate correction transformation matrix to achieve online calibration, which is a signal algorithm-based calibration.

[0005] The prior art, CN202311433599.3, describes an automated butt welding system that focuses on filling the ring chamber to eliminate dimensional deviations and using an automatic operation unit to fix the pipe fittings, thus solving the pipe fitting adaptation problem during welding.

[0006] The solution of achieving fully automatic alignment of the welding torch through mechanical hardware is not common in existing technology, which results in insufficient welding accuracy for thin-walled pipes. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a welding torch self-calibration device, which improves the welding accuracy of pipe fittings.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A welding torch self-calibration device, characterized in that it includes a calibration component and a welding torch component; The calibration assembly includes a reference calibration column, two symmetrically arranged measuring units, a guide unit, a transmission detection unit, and a rotation unit that work together: the reference calibration column is located at the center of the calibration assembly to provide a calibration reference; when the measuring unit moves, it feeds back a displacement signal through the transmission detection unit; the rotation unit drives the entire calibration assembly to rotate around the central axis of the reference calibration column, and a Z-axis displacement sensor is configured to detect the Z-axis position offset of the welding torch. The welding torch assembly is provided with a positioning contact and a welding contact at its end. The positioning contact is used to contact and position with the two measuring units of the calibration assembly, and the welding contact is used for subsequent welding operations. The welding gun assembly can be driven by a robot to complete multi-degree-of-freedom motion. During calibration, the positioning contact point abuts against the measuring unit, and the welding gun assembly and calibration assembly rotate synchronously. When there is an offset distance between the center of the positioning contact point of the welding gun assembly and the center of the reference calibration column, the measuring unit will be displaced and converted into a displacement signal. The robot adjusts the center position of the positioning contact point according to the displacement signal.

[0009] Furthermore, the calibration device also includes a drive unit, which drives a pair of measuring units to move in opposite directions or away from each other along the guide unit. The drive unit is an elastically reset type drive, including a left calibration cylinder and a right calibration cylinder.

[0010] Furthermore, the measuring unit includes a left measuring plate and a right measuring plate, the guiding unit includes a linear guide rail, and the left calibration cylinder and the right calibration cylinder respectively drive the left measuring plate and the right measuring plate to slide along the linear guide rail.

[0011] Furthermore, the transmission detection unit includes a transmission component and a measuring unit that are rigidly connected. The transmission component includes a left positioning plate and a right positioning plate, and the measuring unit includes a left displacement sensor and a right displacement sensor. The positioning plate and the right positioning plate are respectively fixedly connected to the left measuring plate and the right measuring plate.

[0012] Furthermore, the welding torch assembly includes an inner torch body, an outer torch body, an outer torch body cylinder, and a pressure sensor working together: the inner torch body is fixedly installed, the outer torch body cylinder drives the outer torch body to move axially relative to the inner torch body, the pressure sensor detects the contact pressure of the outer torch body in real time to control the movement stroke, the inner torch body and the outer torch body are respectively provided with positioning contacts and welding contact points at their ends, when the outer torch body cylinder drives the outer torch body to move to the end of the stroke, the positioning contacts of the outer torch body contact the corresponding left and right measuring plates, and under the action of the return spring of the drive unit, the two sets of positioning contacts clamp and fit tightly with the left and right measuring plates to form a synchronous linkage structure.

[0013] A welding torch self-calibration method, characterized by comprising the following steps: (1) Zeroing the reference: The drive unit drives a pair of measuring units to clamp the reference structure, and synchronously drives the transmission component and the displacement detection component to move together. After the state stabilizes, the system sets the measured value of the displacement detection component to zero, and then the drive unit resets to make the measuring unit float. (2) Welding gun positioning: The robot drives the welding gun assembly to move, so that the positioning contact of the inner gun body contacts one of the measuring units. When the pressure sensor detects the value, it stops moving. The outer gun body cylinder adjusts the position of the outer gun body, so that the positioning contact of the outer gun body contacts another measuring unit, forming a clamping and bonding linkage state. (3) Dual-axis calibration: The rotating unit drives the calibration component to rotate around the central axis of the reference calibration column, while the robot drives the welding gun component to rotate synchronously around the central axes of the two sets of positioning contacts; if there is an eccentric deviation between the two central axes, the positioning contacts drive the measuring unit to move along the guide mechanism, the displacement detection component feeds back the data in real time, the system calculates the offset parameters based on the data and adjusts the robot position so that the two central axes coincide, and completes the horizontal dual-axis calibration; (4) Z-axis calibration: The robot adjusts the welding torch posture so that the welding torch Z-axis positioning surface faces the Z-axis displacement sensor, drives the welding torch to move a preset distance toward the Z-axis displacement sensor, the Z-axis displacement sensor collects the reading and compares it with the preset standard value, calculates the Z-axis offset and then makes compensation adjustment to complete the Z-axis calibration. (5) Calibration complete: After all X / Y / Z three-axis calibrations are completed, the system saves the calibration parameters. The welding torch uses the calibration point as a reference and, driven by the robot, completes the high-precision welding operation of the thin-walled tubes one by one according to the arrangement array of the thin-walled tubes.

[0014] Furthermore, the specific steps for zeroing the reference are as follows: After starting the calibration program, the left calibration cylinder and the right calibration cylinder simultaneously circulate air, driving the left measuring plate and the right measuring plate to move towards each other along the linear guide rail until they precisely clamp the reference calibration column. At this time, the measuring plate drives the corresponding left positioning plate and right positioning plate to move synchronously, pressing the telescopic contacts of the left displacement sensor and the right displacement sensor to a stable position.

[0015] Further, the specific steps for positioning the welding torch are as follows: After the reference is zeroed, the left and right calibration cylinders are shut off. Under the action of the built-in reset spring, the left and right measuring plates move synchronously in opposite directions, releasing the reference calibration column and resetting it to the initial position. Then, the robot drives the welding torch assembly to move, aligning the positioning contacts of the inner torch body and the outer torch body with the sides of the left and right measuring plates respectively. The positioning contacts of the inner torch body are controlled to contact the end face of the left measuring plate. The pressure sensor monitors the contact pressure in real time. When the pressure value reaches the preset threshold, the robot stops moving to ensure stable contact pressure. Afterward, the outer torch body cylinder is vented to drive the outer torch body to open, so that the positioning contacts of the outer torch body correspond to the right measuring plate. Then, the outer torch body cylinder is controlled to move in the opposite direction, driving the outer torch body to move towards the inner torch body until the cylinder reaches the end of its stroke. At this time, the positioning contacts of the outer torch body are in close contact with the right measuring plate.

[0016] Furthermore, the specific steps of dual-axis calibration are as follows: start the servo motor to drive the entire calibration component to rotate at a constant speed around the central axis of the reference calibration column. At the same time, the robot drives the welding gun assembly to rotate synchronously around the central axes of the inner and outer gun body positioning contacts. If there is a concentricity deviation between the central axis of the welding gun positioning contact and the central axis of the reference calibration column, during the rotation, the positioning contact will drive the left and right measuring plates to produce a small displacement along the linear guide rail. This displacement is transmitted to the displacement sensor through the positioning plate, so that the left and right displacement sensors output the corresponding measurement values.

[0017] Furthermore, the specific steps for Z-axis calibration are as follows: After X / Y axis calibration is completed, the robot drives the welding torch assembly to rotate 90° so that the Z-axis positioning surface of the welding torch faces the detection direction of the Z-axis displacement sensor. Then, the welding torch is controlled to move a preset distance towards the sensor along the Z-axis direction. The Z-axis displacement sensor collects the position data of the positioning surface in real time and compares the measured value with the standard Z-axis position value preset by the system to calculate the position deviation in the Z-axis direction.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects:

[0019] This device, through structural integration and algorithm optimization, possesses the following core technological advantages: First, it adopts a collaborative design of mechanical structure and sensors to achieve automated calibration in the X / Y / Z axes without manual intervention, significantly improving calibration efficiency. Second, through zeroing the reference calibration column and fusing data from multiple sensors, it achieves high calibration accuracy, effectively compensating for welding torch installation and robot motion deviations, ensuring the welding quality of thin-walled tubes. Third, it integrates a dual-contact structure for positioning and welding, simplifying the device layout while balancing calibration functionality and welding performance. Fourth, it is compatible with six-axis robot operations, offering strong versatility and applicability to welding calibration scenarios for thin-walled tubes of different specifications, making it widely applicable. Attached Figure Description

[0020] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments of the invention and, together with the specification, further serve to explain the principles of the invention and enable those skilled in the art to practice and use the invention.

[0021] Figure 1 This is one of the three-dimensional structural schematic diagrams of a welding torch self-calibration device; Figure 2 This is the second three-dimensional structural schematic diagram of a welding torch self-calibration device; Figure 3 A diagram showing the calibration components of a welding torch self-calibration device; Figure 4 This is a diagram showing the assembly of a welding torch for a welding torch self-calibration device.

[0022] Figure label: Calibration Components: 1. Reference Calibration Column: 1-1. Left Measuring Plate: 1-2. Right Measuring Plate: 1-3. Linear Guide Rail: 1-4. Calibration Component Fixing Plate: 1-5. Left Calibration Cylinder: 1-6. Right Calibration Cylinder: 1-7. Left Positioning Plate: 1-8. Right Positioning Plate: 1-9. Left Displacement Sensor: 1-10. Right Displacement Sensor: 1-11. Z-Axis Displacement Sensor: 1-12. Servo Motor: 1-13. Welding Torch Assembly: 2. Inner Torch Body: 2-1. Outer Torch Body: 2-2. Outer Torch Body Cylinder: 2-3. Pressure Sensor: 2-4. Welding Torch Base: 2-5.

[0023] As shown in the figure, specific structures and devices are marked in the figure to clearly illustrate the structure of the embodiments of the present invention. However, this is only for illustrative purposes and is not intended to limit the present invention to this specific structure, device and environment. Those skilled in the art can adjust or modify these devices and environments according to specific needs. Detailed Implementation

[0024] The self-calibration device for welding torches provided by the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art can use other alternative methods to implement some well-known technologies; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0025] Please refer to the attached diagram. The welding torch self-calibration device includes calibration component 1 and welding torch component 2.

[0026] The calibration component 1 is the core of the entire device for reference positioning and detection. Its structural layout forms a symmetrical measurement system around the reference calibration column 1-1. Specifically, it includes the reference calibration column 1-1, left measuring plate 1-2, right measuring plate 1-3, linear guide rail 1-4, calibration component fixing plate 1-5, left calibration cylinder 1-6, right calibration cylinder 1-7, left positioning plate 1-8, right positioning plate 1-9, left displacement sensor 1-10, right displacement sensor 1-11, Z-axis displacement sensor 1-12, and servo motor 1-13.

[0027] The reference calibration column 1-1 is coaxially mounted at the center of the calibration assembly 1, serving as the core reference component for calibration. Its outer circumferential surface is precision-machined to ensure accurate positioning of the left and right measuring plates after clamping, providing a unified reference for subsequent displacement measurements. The linear guide rail 1-4 is fixed horizontally to the calibration assembly fixing plate 1-5. The left measuring plate 1-2 and right measuring plate 1-3 are symmetrically slidably mounted on the linear guide rail 1-4, allowing for smooth movement in opposite directions along the guide rail axis. The guiding accuracy of the linear guide rail 1-4 directly ensures the straightness of the measuring plate movement, thereby improving displacement detection accuracy.

[0028] The left measuring plate 1-2 and the right measuring plate 1-3 are independently driven by the left calibration cylinder 1-6 and the right calibration cylinder 1-7, respectively. Both the left and right calibration cylinders are single-acting cylinders with automatic reset function after gas interruption. The reset power is provided by the reset spring inside the cylinder, which ensures that the measuring plate quickly disengages from the reference calibration column and welding torch electrode contacts after calibration, avoiding interference with subsequent welding operations. The left measuring plate 1-2 and the left positioning plate 1-8 are an integral structure or rigidly connected, and the right measuring plate 1-3 and the right positioning plate 1-9 are similarly connected. The positioning plate moves synchronously with the measuring plate to achieve synchronous displacement transmission.

[0029] Both the left displacement sensor 1-10 and the right displacement sensor 1-11 adopt a contact-type telescopic contact structure. Their fixed ends are rigidly mounted on the calibration component fixing plate 1-5 via a bracket. The movable contacts maintain constant contact with the end faces of the left positioning plate 1-8 and the right positioning plate 1-9, respectively. The contacts can adaptively extend and retract as the positioning plates move, thereby converting the displacement of the measuring plates into an electrical signal output, realizing real-time acquisition of displacement data. All the above structural components are integrated on the calibration component fixing plate 1-5. This fixing plate is connected to the output end of the servo motor 1-13, and the output shaft of the servo motor 1-13 is concentrically set with the central axis of the reference calibration column 1-1, ensuring that the reference calibration column 1-1 is always at the center of rotation when the servo motor drives the calibration component 1 to rotate as a whole, avoiding additional deviations during rotation.

[0030] In addition, a Z-axis displacement sensor 1-12 is fixedly mounted on the outer frame of the calibration component 1. The sensor adopts a non-contact or contact measurement structure, and its detection direction is arranged in the vertical direction. It is specifically used to collect the position data of the welding torch in the Z-axis direction, providing a detection basis for the deviation calibration in the Z-axis direction, and realizing three-axis all-round calibration coverage.

[0031] The welding torch assembly 2 is the core component for performing welding operations. It also has a structure design that can cooperate with the calibration assembly to achieve self-calibration. It mainly consists of an inner torch body 2-1, an outer torch body 2-2, an outer torch body cylinder 2-3, a pressure sensor 2-4, and a welding torch base 2-5. The whole assembly can be driven by a six-axis robot to achieve multi-posture movement in space, meeting the welding and calibration needs of different positions.

[0032] The inner gun body 2-1 is rigidly fixed to the welding torch base 2-5 by fasteners, maintaining a fixed position during operation and serving as the installation reference and guide carrier for the outer gun body 2-2. The outer gun body 2-2 adopts a sleeve structure, coaxially sleeved outside the inner gun body 2-1, with a clearance fit between them to ensure that the outer gun body 2-2 can move smoothly along the axial direction of the inner gun body 2-1. The cylinder body of the outer gun body cylinder 2-3 is fixed to one end of the outer gun body 2-2, and the piston rod forms a transmission connection with the inner gun body 2-1 or the welding torch base 2-5. The extension and retraction of the cylinder drives the outer gun body 2-2 to achieve axial displacement adjustment relative to the inner gun body 2-1. The pressure sensor 2-4 is connected in series with the outer gun body cylinder 2-3 to detect the output pressure of the outer gun body cylinder 2-3 in real time, and accurately controls the movement stroke and contact pressure of the outer gun body 2-2 through pressure feedback.

[0033] To accommodate both calibration positioning and welding operations, both the inner gun body 2-1 and the outer gun body 2-2 have two independent sets of electrode contacts integrated at their ends: one set is a positioning contact, specifically used to engage with the left and right measuring plates of the calibration component to achieve spatial positioning and deviation detection of the welding gun; the other set is a welding contact, used to contact the thin-walled tube to be welded during the actual production process to complete the welding operation. The two sets of contacts are arranged independently and do not interfere with each other, ensuring that calibration accuracy does not affect welding performance, while simplifying the overall structure of the device and improving integration.

[0034] The calibration process of this device adopts an automated workflow of reference zeroing, welding torch alignment, rotation detection, and deviation compensation, requiring no manual intervention. It boasts high calibration accuracy and efficiency. The specific steps are as follows: Zeroing the reference pressure: After the calibration procedure is started, the left calibration cylinder 1-6 and the right calibration cylinder 1-7 simultaneously circulate air, driving the left measuring plate 1-2 and the right measuring plate 1-3 to move towards each other along the linear guide rail 1-4 until they precisely clamp the reference calibration column 1-1. At this time, the measuring plates drive the corresponding left positioning plate 1-8 and right positioning plate 1-9 to move synchronously, pressing the telescopic contacts of the left displacement sensor 1-10 and the right displacement sensor 1-11 to a stable position. After the system detects that the cylinder pressure has stabilized, it sets the current measured values ​​of the left and right displacement sensors to zero, establishing the reference zero point for displacement detection, and completing the reference calibration before calibration.

[0035] Welding torch alignment stage: After the reference is zeroed, the left and right calibration cylinders are shut off. Under the action of the built-in reset spring, the left and right measuring plates move synchronously in opposite directions, releasing the reference calibration column 1-1 and resetting to the initial position. Subsequently, the six-axis robot drives the welding torch assembly 2 to move, aligning the positioning contacts of the inner torch body 2-1 and the outer torch body 2-2 with the sides of the left measuring plate 1-2 and right measuring plate 1-3 respectively. The robot controls the positioning contacts of the inner torch body 2-1 to contact the end face of the left measuring plate 1-2. Pressure sensor 2-4 monitors the contact pressure in real time. When the pressure value reaches a preset threshold, the robot stops moving to ensure stable contact pressure. Then, the outer torch body cylinder 2-3 is vented to open the outer torch body 2-2, aligning its positioning contacts with the right measuring plate 1-3. The outer torch body cylinder 2-3 is then controlled to reverse its movement, driving the outer torch body 2-2 towards the inner torch body 2-1 until the cylinder reaches the end of its stroke. At this point, the positioning contacts of the outer torch body 2-2 are in tight contact with the right measuring plate 1-3. In this state, the positioning contacts of the left and right measuring plates and the inner and outer torch bodies are clamped together under the force of the cylinder's return spring, forming a rigid connection structure that allows for synchronous displacement.

[0036] X / Y axis deviation detection stage: Servo motors 1-13 are started, driving the calibration assembly 1 to rotate uniformly around the central axis of the reference calibration column 1-1. Simultaneously, the robot drives the welding torch assembly 2 to rotate synchronously around the central axes of the inner and outer torch body positioning contacts. If there is a concentricity deviation between the central axis of the welding torch positioning contact and the central axis of the reference calibration column 1-1, during rotation, the positioning contact will cause the left and right measuring plates to generate a slight displacement along the linear guide rail 1-4. This displacement is transmitted to the displacement sensors through the positioning plates, causing the left and right displacement sensors to output corresponding measurement values. By collecting displacement data in real time during the rotation process and combining it with rotation angle information, the system can accurately calculate the offset direction and specific offset of the welding torch positioning contact central axis relative to the central axis of the reference calibration column, thus completing the deviation detection in the X / Y axis direction.

[0037] X / Y axis deviation compensation stage: Based on the detected X / Y axis offset direction and offset amount, the system automatically generates robot motion position adjustment instructions to compensate and correct the robot's six-axis motion parameters until the center axis of the welding torch positioning contact is completely coincident with the center axis of the reference calibration column 1-1, thus completing the calibration of the X / Y axis direction.

[0038] Z-axis deviation calibration stage: After X / Y-axis calibration, the robot drives the welding torch assembly to rotate 90°, aligning the welding torch's Z-axis positioning surface with the detection direction of Z-axis displacement sensors 1-12. Then, the robot controls the welding torch to move a preset distance along the Z-axis towards the sensors. The Z-axis displacement sensors collect position data of the positioning surface in real time and compare the measured values ​​with the system's preset standard Z-axis position values ​​to calculate the position deviation in the Z-axis direction. The system compensates for the robot's Z-axis motion parameters based on the deviation value, causing the welding torch to return to the standard position in the Z-axis direction, thus completing the Z-axis calibration.

[0039] Calibration complete: After all X / Y / Z three-axis calibrations are completed, the system saves the calibration parameters. Using the calibration point as a reference, the welding torch, driven by the robot, completes the high-precision welding operation of the thin-walled tubes one by one according to the arrangement array of the thin-walled tubes.

[0040] This device employs three ranging sensors (left and right displacement sensors and a Z-axis displacement sensor) for collaborative calibration. Its core principle is based on spatial three-point positioning and unified coordinate calibration. Through the fusion of non-coplanar measurement data from multiple sensors, it accurately determines the spatial coordinates of the welding torch tip reference point and aligns it with the theoretical coordinate system, achieving precise adjustment of the welding torch position. This process is divided into four key steps: First, the coordinate systems of the three ranging sensors are calibrated. Using the robot's base coordinate system or the tooling's positioning coordinate system as a unified world coordinate system, the theoretical spatial position of the welding torch's zero point is determined through the robot's initial teaching method. Simultaneously, the installation position parameters of each sensor are collected, and the transformation matrices (including rotation and translation vectors) of each sensor's measurement coordinate system relative to the world coordinate system are established. The core purpose of this step is to eliminate positional deviations caused by the independent installation of each sensor, unifying the measurement data from the three sensors under the same reference coordinate system. This ensures the accuracy of subsequent data fusion and deviation calculation, laying the foundation for high-precision calibration.

[0041] Through the above-mentioned calibration mechanical actions, the three ranging sensors synchronously collect the three-dimensional coordinates of the center of the inner and outer gun body positioning contact points: each sensor first outputs the coordinate data (xi,i,zi) of the corresponding feature point in its own measurement coordinate system, and then, through the transformation matrix established in step 4.1, converts the local coordinate data of each sensor into unified coordinates (Xi,Yi,Zi) in the world coordinate system, so as to achieve accurate representation of the spatial position of the feature point.

[0042] Based on the pre-defined geometric model of the welding torch, and combined with the coordinate data of the inner and outer torch body positioning contacts in the world coordinate system, the actual spatial attitude of the welding torch and the relative positions of its feature points in the welding torch's own coordinate system are calculated using spatial geometric algorithms (such as the least squares method and the vector method). Subsequently, based on the design dimensions of the welding torch, the actual spatial coordinates of the torch end reference point are calculated along the torch's axis. These coordinates represent the current actual zero-point position of the welding torch.

[0043] The actual zero-point coordinates of the welding torch obtained from the calculation are compared with the theoretical zero-point coordinates preset by the system to calculate the positional deviation values ​​(ΔX, ΔY, ΔZ) in the X / Y / Z axes. These deviation values ​​are then written into the parameter compensation table of the robot motion controller, completing the calibration update of the welding torch zero point. To further reduce the influence of sensor measurement errors and random interference, the system can correct the deviation data through multiple repeated calibration measurements and averaging, as well as least squares fitting optimization, thereby improving the stability of calibration accuracy and ensuring the consistency of welding operations.

[0044] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0045] The above description is only a preferred embodiment 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 should also be considered within the scope of protection of the present invention.

Claims

1. A welding torch self-calibration device, characterized in that, Includes a calibration component (1) and a welding torch component (2); The calibration component (1) includes a reference calibration column, two symmetrically arranged measuring units, a guide unit, a transmission detection unit, and a rotation unit that work together: the reference calibration column is located at the center of the calibration component (1) to provide a calibration reference; when the measuring unit moves, it feeds back the displacement signal through the transmission detection unit; the rotation unit drives the calibration component (1) to rotate around the central axis of the reference calibration column; and a Z-axis displacement sensor (1-12) is configured to detect the Z-axis position offset of the welding torch. The welding torch assembly (2) is provided with a positioning contact and a welding contact at its end. The positioning contact is used to contact and position with the two measuring units of the calibration assembly (1), and the welding contact is used for subsequent welding operations. The welding gun assembly (2) can be driven by the robot to complete multi-degree-of-freedom motion. During calibration, the positioning contact point abuts against the measuring unit, and the welding gun assembly (2) and the calibration assembly (1) rotate synchronously. When there is an offset distance between the center of the positioning contact point of the welding gun assembly (2) and the center of the reference calibration column, the measuring unit will be displaced and converted into a displacement signal. The robot adjusts the center position of the positioning contact point according to the displacement signal.

2. The welding torch self-calibration device according to claim 1, characterized in that, The calibration device further includes a drive unit, which drives a pair of measuring units to move in opposite directions or away from each other along the guide unit. The drive unit is an elastic reset type drive, including a left calibration cylinder (1-6) and a right calibration cylinder (1-7).

3. The welding torch self-calibration device according to claim 2, characterized in that, The measuring unit includes a left measuring plate (1-2) and a right measuring plate (1-3). The guiding unit includes a linear guide rail (1-4). The left calibration cylinder (1-6) and the right calibration cylinder (1-7) respectively drive the left measuring plate (1-2) and the right measuring plate (1-3) to slide along the linear guide rail (1-4).

4. The welding torch self-calibration device according to claim 1, characterized in that, The transmission detection unit includes a transmission component and a measuring unit that are rigidly connected. The transmission component includes a left positioning plate (1-8) and a right positioning plate (1-9). The measuring unit includes a left displacement sensor (1-10) and a right displacement sensor (1-11). The positioning plate (1-8) and the right positioning plate (1-9) are respectively fixedly connected to the left measuring plate (1-2) and the right measuring plate (1-3).

5. The welding torch self-calibration device according to claim 1, characterized in that, The welding torch assembly (2) includes an inner torch body (2-1), an outer torch body (2-2), an outer torch body cylinder (2-3), and a pressure sensor (2-4) working together: the inner torch body (2-1) is fixedly set, the outer torch body cylinder (2-3) drives the outer torch body (2-2) to move axially relative to the inner torch body (2-1), and the pressure sensor (2-4) detects the contact pressure of the outer torch body (2-2) in real time to control the movement stroke. The inner torch body (2-1) and the outer torch body (2-2) are respectively provided with positioning contacts and welding contact points. When the outer torch body cylinder (2-3) drives the outer torch body (2-2) to move to the end of the stroke, the positioning contacts of the outer torch body (2-2) contact the corresponding left measuring plate (1-2) and right measuring plate (1-3). Under the action of the reset spring of the drive unit, the two sets of positioning contacts are clamped and attached to the left measuring plate (1-2) and right measuring plate (1-3) to form a synchronous linkage structure.

6. A welding torch self-calibration method based on the device described in any one of claims 1-5, characterized in that, Includes the following steps: (1) Zeroing the reference: The drive unit drives a pair of measuring units to clamp the reference structure, and synchronously drives the transmission component and the displacement detection component to move together. After the state stabilizes, the system sets the measured value of the displacement detection component to zero, and then the drive unit resets to make the measuring unit float. (2) Welding gun positioning: The robot moves the welding gun assembly so that the positioning contact of the inner gun body (2-1) contacts one of the measuring units. When the pressure sensor (2-4) detects the value, it stops moving. The outer gun body cylinder (2-3) adjusts the position of the outer gun body so that the positioning contact of the outer gun body (2-2) contacts another measuring unit, forming a clamping and bonding linkage state. (3) Dual-axis calibration: The rotating unit drives the calibration component (1) to rotate around the central axis of the reference calibration column. At the same time, the robot drives the welding gun component to rotate synchronously around the central axes of the two sets of positioning contacts. If there is an eccentric deviation between the two central axes, the positioning contacts drive the measuring unit to move along the guide mechanism. The displacement detection component feeds back the data in real time. The system calculates the offset parameters based on the data and adjusts the robot position so that the two central axes coincide, thus completing the horizontal dual-axis calibration. (4) Z-axis calibration: The robot adjusts the welding torch posture so that the welding torch Z-axis positioning surface faces the Z-axis displacement sensor, drives the welding torch to move a preset distance toward the Z-axis displacement sensor, the Z-axis displacement sensor (1-12) collects the reading and compares it with the preset standard value, calculates the Z-axis offset and then makes compensation adjustment to complete the Z-axis calibration. (5) Calibration complete: After all X / Y / Z three-axis calibrations are completed, the system saves the calibration parameters. The welding torch uses the calibration point as a reference and, driven by the robot, completes the high-precision welding operation of the thin-walled tubes one by one according to the arrangement array of the thin-walled tubes.

7. The welding torch self-calibration method according to claim 5, characterized in that, The specific steps for zeroing the reference are as follows: After starting the calibration program, the left calibration cylinder (1-6) and the right calibration cylinder (1-7) simultaneously circulate air, driving the left measuring plate (1-2) and the right measuring plate (1-3) to move towards each other along the linear guide rail (1-4) until they precisely clamp the reference calibration column (1-1). At this time, the measuring plate drives the corresponding left positioning plate (1-8) and right positioning plate (1-9) to move synchronously, pressing the telescopic contacts of the left displacement sensor (1-10) and the right displacement sensor (1-11) to a stable position.

8. The welding torch self-calibration method according to claim 5, characterized in that, The specific steps for positioning the welding torch are as follows: After the reference is zeroed, the left and right calibration cylinders are cut off. Under the action of the built-in reset spring, the left and right measuring plates move synchronously in opposite directions, release the reference calibration column (1-1) and reset to the initial position. Then the robot drives the welding torch assembly (2) to move, aligning the positioning contacts of the inner torch body (2-1) and the positioning contacts of the outer torch body (2-2) with the sides of the left measuring plate (1-2) and the right measuring plate (1-3) respectively. Control the positioning contacts of the inner torch body (2-1) to contact the end face of the left measuring plate (1-2). The pressure sensor (2-4) monitors the contact pressure in real time. When the pressure value reaches the preset threshold, the robot stops moving to ensure that the contact pressure is stable. Then, the outer gun body cylinder (2-3) is vented to drive the outer gun body (2-2) to open, so that the positioning contact of the outer gun body (2-2) corresponds to the right measuring plate (1-3). Then, the outer gun body cylinder (2-3) is controlled to move in the opposite direction, driving the outer gun body (2-2) to move towards the inner gun body (2-1) until the cylinder reaches the end of its stroke. At this time, the positioning contact of the outer gun body (2-2) is in close contact with the right measuring plate (1-3).

9. The welding torch self-calibration method according to claim 5, characterized in that, The specific steps of dual-axis calibration are as follows: Start the servo motor (1-13) to drive the calibration component (1) to rotate at a constant speed around the central axis of the reference calibration column (1-1). At the same time, the robot drives the welding gun component (2) to rotate synchronously around the central axis of the inner and outer gun body positioning contacts. If there is a concentricity deviation between the central axis of the welding gun positioning contact and the central axis of the reference calibration column (1-1), during the rotation, the positioning contact will drive the left and right measuring plates to generate a small displacement along the linear guide rail (1-4). This displacement is transmitted to the displacement sensor through the positioning plate, so that the left and right displacement sensors output the corresponding measurement values.

10. The welding torch self-calibration method according to claim 5, characterized in that, The specific steps for Z-axis calibration are as follows: After X / Y axis calibration is completed, the robot drives the welding torch assembly to rotate 90° so that the Z-axis positioning surface of the welding torch faces the detection direction of the Z-axis displacement sensor (1-12). Then, the welding torch is controlled to move a preset distance towards the sensor along the Z-axis direction. The Z-axis displacement sensor (1-12) collects the position data of the positioning surface in real time and compares the measured value with the preset standard Z-axis position value of the system to calculate the position deviation in the Z-axis direction.

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