Laser Cladding Point Detection Probe Device and Method for Calibration Using the Same

Abstract

The present invention discloses a detection probe device for laser cladding points, which comprises a probe base, a detection probe, a quick-connect joint, a spring, and an annular conductor; the probe base is provided with two stepped holes of different sizes along the center line; the needle part of the detection probe extends out of the small hole of the probe base, and the positioning slider at its tail is matched with the large hole of the probe base; the quick-connect joint is connected to the bottom of the large hole of the probe base through the thread on the large outer circle; the spring is arranged in the large hole of the probe base, and its upper and lower ends are respectively in contact with the positioning slider and the quick-connect joint; the annular conductor is embedded in the top surface of the large hole of the probe base, and the protruding contact on the detection probe is in contact with the annular conductor. The detection probe device of the present invention has high compatibility with the laser cladding optical head, accurate positioning, convenient replacement, and simple operation, improving the processing quality and processing efficiency. The present invention also discloses a method for calibration using the detection probe device.

Description

Technical Field

[0001] The present invention relates to the field of laser processing, and particularly to a detection probe device for laser cladding points and a method for calibrating the coordinates of a surface to be processed of a part by using the same. Background Art

[0002] At present, laser cladding has become one of the common methods for surface treatment of parts. The common laser cladding processing methods are: manually teaching a robot or an automated device such as a numerical control machine tool to edit a processing program, and editing a processing program according to the dimensions of a part design drawing or the dimensions measured from a physical object.

[0003] Before editing the processing program, it is necessary to detect and calibrate the part. Since the current detection tools used for calibration cannot be compatible with the cladding optical head, it is necessary to remove the cladding optical head from the device and then install the detection tool on the device. The disadvantages of this installation method are: First, because the cladding optical head involves the requirements of optical path, water path, gas path transmission and sealing protection, the operation of disassembling the cladding optical head is complex and cumbersome, time-consuming and easy to damage the laser cladding optical head; Second, due to the large size difference between the detection tool and the cladding optical head, the data measured for the part by it will be somewhat distorted relative to the cladding optical head and cannot accurately reflect, and there is a risk of interference and collision between the part and the cladding optical head when using the cladding optical head for cladding.

[0004] At present, the methods and disadvantages for detecting and verifying the trajectory points of part processing before editing the processing program are as follows: First, manual visual inspection and verification, that is, manually detecting and verifying each point one by one. Due to the influence of human factors (operation experience, operator state), the accuracy of the detection result is poor, the size difference from the part is large, the efficiency is low, and it takes a long time; Second, detecting by using existing detection tools (such as a numerical control coordinate measuring instrument) or an independent detection probe additionally installed on the processing device. Since the size difference between the detection tool and the cladding optical head is large, the data measured for the part by it will be somewhat distorted relative to the cladding optical head and cannot accurately reflect, and there is a risk of interference and collision between the part and the cladding optical head when using the cladding optical head for cladding; In addition, the size data of the point, line and surface of the part provided by the detection tool needs to be calculated and transformed through a series of processes to generate the spatial three-dimensional shape size and the motion trajectory point information of the part processing program. The whole process is complex and time-consuming and cannot meet the timeliness requirements; Third, modeling with reference to the design drawing and using computer-aided manufacturing software to generate the processing program and motion trajectory of the part to be processed. Since the part to be repaired has been used and worn, the physical object of the part to be processed does not match the motion trajectory of the processing program; In addition, the motion trajectory generated by the software is usually the tool center point (theoretical position), but the motion process also involves a large number of complex problems such as angle, attitude, stroke limit, etc. At this time, a large amount of manual correction, adjustment, modification, etc. are required. Therefore, the whole process is complex and time-consuming and cannot meet the timeliness requirements. Summary of the Invention

[0005] The problem to be solved by the present invention is to provide a detection probe device for laser cladding points, which has high compatibility with the laser cladding optical head, accurate positioning, convenient replacement, simple operation, and improves the processing quality and efficiency. The present invention also provides a method for calibrating the surface to be machined of a part by using the detection probe device, which obtains accurate data, avoids interference and collision between the cladding optical head and the part, shortens the time for detection and calibration before cladding, so it has good timeliness and greatly reduces the production cost.

[0006] The detection probe device for laser cladding points of the present invention includes a probe base, a detection probe, a quick connector, a spring, and a ring conductor; the probe base is provided with two stepped holes of different sizes along the center line; the needle part of the detection probe extends out of the small hole of the probe base, and the positioning slider at its tail is matched with the large hole of the probe base; the quick connector is connected to the bottom of the large hole of the probe base through the thread on the large outer circle; the spring is arranged in the large hole of the probe base, and its upper and lower ends are respectively in contact with the positioning slider and the quick connector; the ring conductor is embedded in the top surface of the large hole of the probe base, and the protruding contact on the detection probe is in contact with the ring conductor.

[0007] Furthermore, the detection probe device further includes at least two O-ring rubber gaskets. There are at least two upper and lower annular grooves on the inner wall of the small hole of the probe base, and the O-ring rubber gaskets are arranged in the annular grooves and are matched with the needle part of the detection probe.

[0008] Furthermore, the detection probe device further includes spring steel balls, which are arranged in the transverse holes on the small outer circle of the quick connector, and the steel balls slightly protrude from the small outer circle of the quick connector in the free state.

[0009] Furthermore, the detection probe device further includes a plurality of LED lighting sources, which are evenly distributed on the upper end surface of the cylindrical surface of the probe base.

[0010] Furthermore, the detection probe device further includes a plurality of LED indicator lights, which are evenly distributed on the cylindrical surface of the probe base.

[0011] Furthermore, the material of the probe base is insulating engineering plastic.

[0012] The method for calibration by using the detection probe device of the present invention specifically includes the following steps:

[0013] ① Install the detection probe device: Take the inner hole and the end face of the nozzle of the laser cladding optical head as the positioning reference, and install the detection probe device on the laser cladding optical head;

[0014] ② Establish the coordinate system of the detection probe device: Use the tip of the detection probe to approach the tip of the calibration rod at a known spatial coordinate position from different azimuth angles, measure the coordinate differences of each axis of the probe tip relative to the tip of the calibration rod, and generate the coordinate system of the detection probe device (relative to the equipment coordinate system);

[0015] ③ Establish the coordinate system of the part: Use the tip of the detection probe to slowly approach the surface to be machined of the part, and calibrate the origin of the coordinate system of the part, the X-axis quadrant point of the part coordinate system, and the Y-axis quadrant point of the part coordinate system respectively to establish the coordinate system of the part (relative to the equipment coordinate system);

[0016] ④ Detect, verify, calculate, and calibrate the coordinate values of each axis quadrant point of the surface to be machined of the part: The detection probe device moves along each axis of the part coordinate system, and respectively detects the coordinate values of each axis quadrant point of the surface to be machined. The control program automatically calculates the detection results and assigns the values to the corresponding motion points in the machining motion trajectory program for calibration;

[0017] ⑤ Run the machining trajectory for trial operation: The laser cladding head nozzle runs a typical short program slowly and in a non-machining state along the motion trajectory points obtained in step ④. Manually monitor the program running trajectory. If the motion trajectory points coincide with the expected motion nodes, proceed to step ⑥; if the motion trajectory points do not coincide with the expected motion nodes, repeat steps ④ and ⑤ until the motion trajectory points coincide with the expected motion nodes;

[0018] ⑥ Cladding machining: Perform cladding machining on the surface to be machined of the part to meet the technical requirements.

[0019] Among them, in step ④: Before the detection probe moves, its protruding contact always remains in contact with the annular conductor, and loop A2 is conducting; the detection probe slowly approaches the part to be measured. When its tip touches the surface of the part to be measured, loop A2 is conducting and loop A1 is conducting. After the control system receives this signal, the detection probe decelerates forward. After its tip is pressured, the protruding contact separates from the annular conductor, loop A2 is disconnected, and loop A1 is conducting. After the control system receives this signal, the detection probe stops moving forward. The control system automatically reads the current point coordinate value of the device coordinate system and calculates the current point tool coordinate value according to the conversion instruction edited by the program, and automatically assigns it to the corresponding motion program trajectory node. At this time, the tip of the detection probe leaves the part, loop A2 is disconnected, and loop A1 is disconnected. After the control system receives this signal, the detection probe retracts. When the protruding contact re-contacts the annular conductor, loop A2 is conducting and loop A1 is disconnected. After the control system receives this signal, it stops retracting; then repeat the above program to enter the next detection cycle, that is, sequentially execute the "approach - contact - stop - retract" cycle detection program with a smaller movement distance at a lower level until the measurement of the smallest feed unit specified by the programming is completed, which means the detection of one point is completed. The control system automatically reads the coordinate value of the current point relative to the device coordinate system, and obtains the coordinate value of the current point relative to the detection probe device coordinate system through conversion, and automatically assigns it to the corresponding motion program trajectory node, that is, calibrates the point of the part; then continue to execute the detection and calibration of the next point until the detection and calibration of the entire surface to be machined are completed.

[0020] Among them, in step ④: In the execution of the "approach - contact - stop - retract" loop program, for each point, the motion feed unit used later is one order of magnitude smaller than the motion feed unit used in the previous time (such as 1mm, 0.1mm, 0.01mm). By executing the step-by-step reduction of the interval distance (motion) unit, the accurate position of the quadrant point of the surface to be machined can be determined, that is, precise positioning is achieved. Each detection of each point is calculated and assigned. The subsequent assignment will overwrite the previous assignment. The coordinate value of the smallest interval distance unit detected at the last detection point is the measured point coordinate position of the part to be measured in the automated machining equipment coordinate system. This value is automatically recorded and calculated and assigned to the motion trajectory point of the machining program.

[0021] When the present invention detects the trajectory points of the machined surface of a part, the detection probe device can operate in the following two modes: First, automatic detection of points is performed through a pre-edited program. That is, the automated equipment drives the tool end of the equipment to complete the process of "approaching - contacting - stopping - retreating". By detecting the probe contacting or leaving the surface of the part to be machined, the conduction or cut-off of the circuit forms an electrical signal output to the control system, enabling the control system to judge the detection result and automatically calculate and assign the point coordinates. Second, manual detection and verification of points are carried out. That is, manual operation is used to complete the work of "approaching - contacting - stopping - retreating" and recording and assignment of the quadrant points: When the equipment is manually advanced and the detection probe contacts the part to be measured, the control system receives the signal of the conduction of A1 and A2, and outputs a signal to the LED indicator in real time. The LED indicator flashes and stays on constantly to assist manual detection. After the detection result is manually input into the control system, the point coordinates are automatically calculated and assigned. When the equipment is manually retreated and the detection probe leaves the part to be measured, after the control system receives the signal of the on / off of A1 and A2, it outputs a signal to the LED prompt indicator in real time, and the LED indicator dims. That is, during the process of "approaching - contacting - stopping - retreating", the control system that receives the electrical signal of the conduction or cut-off of the circuit outputs a signal to the LED indicator through high and low level signals, causing it to emit light signals such as bright, dark, and flashing at different frequencies, thus facilitating the operator to observe the equipment status.

[0022] The advantages of the detection probe device of the present invention are as follows: First, the detection probe device has high compatibility with the laser cladding head and can be conveniently installed on the laser cladding head, avoiding damage to the laser cladding head. Second, since the laser cladding head drives the detection probe device to move together for the detection and calibration of the part, the data obtained is relatively more authentic with respect to the laser cladding head, and there is no risk of interference and collision between the laser cladding head and the part during cladding.

[0023] The advantages of the method for calibrating the surface to be machined of the part in the present invention are as follows: First, due to the high compatibility between the detection probe device and the laser cladding head, that is, the detection probe device can be directly installed on the laser cladding head, the data measured by the detection tool for the part is relatively more authentic with respect to the laser cladding head. That is, the difference between the motion trajectory points obtained through detection and the actual machining motion trajectory is small, which is beneficial to shortening the pre-trial operation time and thus improving the cladding efficiency. Second, since the laser cladding head and the detection probe device move together during the detection process, a large number of complex problems such as angles, postures, and stroke limits involved in the actual motion process of the laser cladding head during cladding are monitored and adjusted in a timely manner during the detection process. Without the need for manual verification, adjustment, etc., it can be ensured that there is no interference and collision between the laser cladding head and the part during cladding. Third, the program involved in the present invention can automatically execute a series of operations such as calculation, compensation, and assignment, without the need for additional series of operations, greatly saving time. Description of the Drawings

[0024] Figure 1 is a perspective view of the detection probe device for the laser cladding point position of the present invention;

[0025] Figure 2 is the front view of the detection probe device of the present invention;

[0026] Figure 3 is the top view of the detection probe device of the present invention;

[0027] Figure 4 is along Figure 2 the sectional view taken along the B-B line in;

[0028] Figure 5 is the flow chart of the calibration method of the present invention. Detailed implementation mode

[0029] Example 1

[0030] From Figure 1 , Figure 2 , Figure 3 , Figure 4 it can be seen that the detection probe device for the laser cladding point position of the present invention includes a probe base 1, a detection probe 2, a quick-connect joint 3, a spring 4, and an annular conductor 5; the probe base 1 is provided with two stepped holes of different sizes along the center line; the needle part 2-3 of the detection probe 2 extends out of the small hole of the probe base 1, and the positioning slider 2-1 at its tail is matched with the large hole of the probe base 1; the quick-connect joint 3 is connected to the bottom of the large hole of the probe base 1 through the thread on the large outer circle; the spring 4 is arranged in the large hole of the probe base 1, and its upper and lower ends are respectively in contact with the positioning slider 2-1 and the quick-connect joint 3; the annular conductor 5 is embedded in the top surface of the large hole of the probe base 1, and the protruding contact 2-2 on the detection probe 2 is in contact with the annular conductor 5.

[0031] The detection probe device of the present invention realizes the positioning and quick insertion and removal between the detection probe device and the cladding optical head by contacting the bottom surface of the probe base 1 with the outer end surface of the cladding optical head nozzle and matching the small outer circle of the quick-connect joint 3 with the inner hole of the cladding optical head nozzle, that is, it shows that the detection probe device can be well compatible with the cladding optical head.

[0032] Among them: when the detection probe 2 is in a free state, under the action of the spring 4, the protruding contact 2-2 is in contact with the annular conductor 5; when the tip of the detection probe 2 is stressed, the protruding contact 2-2 is separated from the annular conductor 5. A circuit A2 is formed between the protruding contact 2-2 and the annular conductor 5. Among them, the compressible distance of the spring 4 is the up and down movable distance of the detection probe 2 along the center line of the probe base 1.

[0033] Example 2

[0034] The detection probe device of the present invention further includes at least two O-ring rubber seals 6. There are at least two upper and lower annular grooves 1-1 provided on the inner wall of the small hole of the probe base 1. The O-ring rubber seals 6 are arranged in the annular grooves 1-1 and cooperate with the needle part 2-3 of the detection probe 2.

[0035] The O-ring rubber seals 6 play a role in supporting the detection probe 2, delay the wear of the needle part 2-3 and the small hole of the probe base 1 when the detection probe 2 moves up and down, and at the same time ensure the insulation between the detection probe 2 and the probe base 1.

[0036] Embodiment 3

[0037] The detection probe device of the present invention further includes spring steel balls 7. The spring steel balls 7 are arranged in the transverse holes on the small outer circle of the quick connector 3, and the steel balls slightly protrude from the small outer circle of the quick connector 3 in the free state.

[0038] The spring steel balls 7 improve the reliability of the fit between the small outer circle of the quick connector 3 and the inner hole of the cladding head nozzle, and thus realize the accurate positioning and quick insertion and removal between the detection probe device and the cladding head.

[0039] Embodiment 4

[0040] The detection probe device of the present invention further includes a plurality of LED lighting sources 8. The LED lighting sources 8 are evenly distributed on the upper end surface of the cylindrical surface of the probe base 1.

[0041] The LED lighting sources 8 are always on, providing illumination for visual observation.

[0042] Embodiment 5

[0043] The detection probe device of the present invention further includes a plurality of LED indicator lights 9. The LED indicator lights 9 are evenly distributed on the cylindrical surface of the probe base 1.

[0044] The LED indicator lights 9 are mainly used to judge whether the detection probe 2 is in contact with the part during the detection process.

[0045] Embodiment 6

[0046] In the detection probe device of the present invention: the material of the probe base 1 is insulating engineering plastic.

[0047] The advantages of the detection probe device of the present invention are as follows: First, the detection probe device has high compatibility with the laser cladding head, can be easily installed on the laser cladding head, and avoids damaging the laser cladding head; Second, since the laser cladding head drives the detection probe device to move together for detecting and calibrating the part, the obtained data is relatively more authentic with respect to the laser cladding head, and there is no danger of interference and collision between the laser cladding head and the part during cladding.

[0048] Embodiment 7

[0049] As Figure 5 shown, the method for calibrating the surface to be machined of a part using the detection probe device of the present invention specifically comprises the following steps:

[0050] ① Install the detection probe device: Taking the inner hole and the end face of the nozzle of the laser cladding optical head as the positioning reference, install the detection probe device on the laser cladding optical head;

[0051] ② Establish the coordinate system of the detection probe device: Using the tip of the detection probe, approach the tip of the calibration rod at a known spatial coordinate position from different azimuth angles, measure the differences of each coordinate axis of the probe tip relative to the tip of the calibration rod, and generate the coordinate system of the detection probe device (relative to the equipment coordinate system);

[0052] ③ Establish the coordinate system of the part: Using the tip of the detection probe, slowly approach the surface to be machined of the part, respectively calibrate the origin of the coordinate system of the part, the X-axis quadrant point of the part coordinate system, and the Y-axis quadrant point of the part coordinate system, and establish the coordinate system of the part (relative to the equipment coordinate system);

[0053] ④ Detect, verify, calculate, and calibrate the coordinate values of each axis quadrant point of the surface to be machined of the part: The detection probe device moves along each axis of the part coordinate system, respectively detects the coordinate values of each axis quadrant point of the surface to be machined, and the control program automatically calculates the detection results and assigns the values to the corresponding motion points in the machining motion trajectory program for calibration;

[0054] ⑤ Try running the machining trajectory: The nozzle of the laser cladding optical head runs a typical small section of the program slowly and in a non-machining state along the motion trajectory points obtained in step ④, and manually monitor the running trajectory of the program. If the motion trajectory points coincide with the expected motion nodes, then proceed to step ⑥; if the motion trajectory points do not coincide with the expected motion nodes, then repeat steps ④ and ⑤ until the motion trajectory points coincide with the expected motion nodes;

[0055] ⑥ Cladding machining: Perform cladding machining on the surface to be machined of the part to meet the technical requirements.

[0056] The functions of the above steps are as follows:

[0057] The function of step ① is: The detection probe device is installed on the laser cladding optical head (equipment tool end) as a special tool, and it has high compatibility with the laser cladding optical head, ensuring that the data measured by the detection tool for the part is relatively authentic with respect to the laser cladding optical head, and there is no risk of interference and collision between the laser cladding optical head and the part during cladding.

[0058] The function of step ② is as follows: Since the position of the calibration rod tip relative to the processing equipment is determined and known, the detection probe device can establish the spatial position relationship between the tip of the detection probe and the equipment coordinate system by detecting the relative coordinate value between the tip of the detection probe and the calibration rod tip. Based on the relative spatial position of the tip of the detection probe with respect to the tool center point where the detection probe is installed on the equipment, the coordinate system of the detection probe device is established. Since this coordinate system is fixed in space relative to the center point of the equipment tool (laser cladding head), tool compensation can be achieved using known fixed values, and the detection results can be converted into the recorded values of the equipment coordinate system in real time.

[0059] The function of step ③ is as follows: Since the position of the detection probe device relative to the processing equipment is determined and known, the coordinate system of the part relative to the processing equipment coordinate system can be determined through the tip of the probe, that is, it can be determined what position, angle, dimensional specifications, etc. the part is in the coordinate system of the equipment.

[0060] The function of step ④ is as follows: Since the coordinate system of the part has been determined, the quadrant point coordinate values of the surface to be processed of the part are further determined, and the coordinate values of the motion nodes in the cladding program are obtained through calculation, and then the processing trajectory is obtained.

[0061] The function of step ⑤ is: Since the surface to be processed by laser cladding is usually an ordered geometric figure with a large area and regular motion trajectory, such as the outer surface of a cylinder, a rectangular plane; therefore, in order to ensure the quality of laser cladding, trial processing needs to be carried out before formal cladding. If there is an error, return to step ④ to re-detect and verify. If there is no error, formal laser cladding is carried out.

[0062] Example 8

[0063] In step ④: Before the detection probe moves, its protruding contact always remains in contact with the annular conductor, and loop A2 is conducting; when the detection probe slowly approaches the part to be measured and its tip touches the surface of the part to be measured, loop A2 is conducting and loop A1 is conducting. After receiving this signal, the control system detects that the probe decelerates forward. After its tip is pressured, the protruding contact separates from the annular conductor, loop A2 is disconnected, and loop A1 is conducting. After receiving this signal, the control system detects that the probe stops moving forward. The control system automatically reads the current point coordinate value of the device coordinate system and calculates the current point tool coordinate value according to the conversion instruction edited by the program, and automatically assigns it to the corresponding motion program trajectory node. At this time, the tip of the detection probe leaves the part, loop A2 is disconnected, and loop A1 is disconnected. After receiving this signal, the control system detects that the probe retracts. When the protruding contact recontacts the annular conductor, loop A2 is conducting and loop A1 is disconnected. After receiving this signal, the control system stops retracting; then the above program is repeated to enter the next detection cycle, that is, the "approach - contact - stop - retract" cycle detection program with a smaller order of magnitude of the motion distance is sequentially executed until the measurement of the smallest feed unit specified by the programming is completed, that is, the detection of one point is completed. The control system automatically reads the coordinate value of the current point relative to the device coordinate system, and obtains the coordinate value of the current point relative to the detection probe device coordinate system through conversion, and automatically assigns it to the corresponding motion program trajectory node, that is, calibrates the point of the part; then continues to execute the detection and calibration of the next point until the detection and calibration of the entire surface to be machined are completed. (Among them, the detection probe and the annular conductor form loop A2, one end of the wire is connected to the probe tail and the other end is connected to the annular conductor; the detection probe and the part to be measured form loop A1, one end of the wire is connected to the probe tail and the other end is connected to the part; the detection probe approaching the part to be measured is forward, and away from the part to be measured is backward)

[0064] In the execution of the "approach - contact - stop - retract" loop program, for each point, the motion feed unit used later is one order of magnitude smaller than the motion feed unit used in the previous time (such as 1mm, 0.1mm, 0.01mm). By executing the step - by - step reduction of the interval distance (motion) unit, the accurate position of the quadrant point of the surface to be machined can be determined, that is, precise positioning is achieved. Each detection of each point is calculated and assigned. The subsequent assignment will overwrite the previous assignment. The coordinate value of the smallest interval distance unit detected at the last detected point is the measured point coordinate position of the part to be measured in the automated processing equipment coordinate system. This value is automatically recorded and calculated and assigned to the motion trajectory point of the processing program. Of course, if the operator intervenes and stops the program execution after a certain calculation and assignment, the point here obtains the current detection calculation assignment result.

[0065] Example 9

[0066] When the present invention detects the trajectory points of the part processing surface, the detection probe device can be in the following two working modes:

[0067] One is to perform automatic detection of the point positions through a pre - edited program, that is, the automated equipment drives the tool end of the equipment to complete the process of "approaching - contacting - stopping - retreating". By detecting whether the detection probe contacts or leaves the surface of the part to be processed, the conduction or disconnection of the circuit forms an electrical signal output to the control system, enabling the control system to judge the detection result and automatically calculate and assign the point position coordinates;

[0068] The second is to manually detect and verify the point positions, that is, manually operate to complete the work of "approaching - contacting - stopping - retreating" at the quadrant points and record and assign values: When manually operating the equipment to move forward and the detection probe contacts the part to be measured, the control system receives the signals of A1 and A2 conduction, and outputs signals to the LED indicator in real - time. The LED indicator flashes and stays on constantly to assist manual detection. After the detection result is manually input into the control system, the point position coordinates are automatically calculated and assigned; When manually operating the equipment to retreat and the detection probe leaves the part to be measured, after the control system receives the signals of A1 and A2 conduction and disconnection, it outputs signals to the LED reminder lamp in real - time, and the LED indicator dims. That is, during the process of "approaching - contacting - stopping - retreating", the control system that receives the electrical signals of the conduction or disconnection of the circuit outputs signals to the LED indicator through high - and low - level signals, making it show light signals such as bright, dark, and flashing at different frequencies, thus facilitating the operator to observe the equipment status. The cramped on - site space, dim light, and existing blind spots for observation are all the reasons for the inconvenience and low efficiency of the existing manual operation. Using light signals to represent the detection status is more intuitive and accurate.

[0069] The advantages of the method for calibrating the surface to be processed of the part in the present invention are as follows: First, due to the high compatibility between the detection probe device and the laser cladding head, that is, the detection probe device can be directly installed on the laser cladding head, the data measured by the detection tool for the part is more authentic relative to the laser cladding head. That is, the difference between the point positions of the motion trajectory obtained through detection and the actual processing motion trajectory is small, which is conducive to shortening the pre - trial operation time and thus improving the efficiency of cladding; Second, since the laser cladding head and the detection probe device move together during the detection process, a large number of complex problems such as angles, postures, and stroke limits involved in the actual motion process of the laser cladding head during cladding are monitored and adjusted in a timely manner during the detection process. Without the need for manual verification, adjustment, etc., it can ensure that there is no interference or collision between the cladding head and the part during cladding; Third, the program involved in the present invention can automatically execute a series of operations such as calculation, compensation, and assignment, without the need for additional series of operations, greatly saving time.

[0070] In summary, the data obtained by the method of the present invention is accurate, avoiding interference and collision between the cladding head and the part, shortening the time for detection and calibration before cladding, so it has good timeliness and greatly reduces the production cost.

Claims

1. A method for calibration using a detection probe device, characterized in that: The detection probe device includes a probe base (1), a detection probe (2), a quick-connect joint (3), a spring (4), and an annular conductor (5); the probe base (1) is provided with two stepped holes of different sizes along the center line; the needle part (2-3) of the detection probe (2) extends out of the small hole of the probe base (1), and the positioning slider (2-1) at its tail is matched with the large hole of the probe base (1); the quick-connect joint (3) is connected to the bottom of the large hole of the probe base (1) through the thread on the large outer circle; the spring (4) is arranged in the large hole of the probe base (1), and its upper and lower ends are respectively in contact with the positioning slider (2-1) and the quick-connect joint (3); the annular conductor (5) is embedded in the top surface of the large hole of the probe base (1), and the protruding contact (2-2) on the detection probe (2) is in contact with the annular conductor (5); the specific steps of the method are as follows: ① Install the detection probe device: Take the inner hole and the end face of the laser cladding head nozzle as the positioning reference, and install the detection probe device on the laser cladding head; ② Establish the coordinate system of the detection probe device: Use the tip of the detection probe to approach the tip of the calibration rod at a known spatial coordinate position from different azimuth angles, measure the coordinate differences of each axis of the probe tip relative to the tip of the calibration rod, and generate the coordinate system of the detection probe device; ③ Establish the coordinate system of the part: Use the tip of the detection probe to slowly approach the surface to be machined of the part, and respectively calibrate the origin of the coordinate system of the part, the X-axis quadrant point of the part coordinate system, and the Y-axis quadrant point of the part coordinate system to establish the coordinate system of the part; ④ Detect, verify, calculate, and calibrate the coordinate values of each axis quadrant point of the surface to be machined of the part: The detection probe device moves along each axis of the part coordinate system, respectively detects the coordinate values of each axis quadrant point of the surface to be machined, and the control program automatically calculates the detection results and assigns the values to the corresponding motion points in the machining motion trajectory program for calibration; ⑤ Try running the machining trajectory: The laser cladding head nozzle runs slowly and in a non-machining state along the motion trajectory points obtained in step ④, and the program running trajectory is manually monitored. If the motion trajectory points coincide with the expected motion nodes, then proceed to step ⑥; if the motion trajectory points do not coincide with the expected motion nodes, then repeat steps ④ and ⑤ until the motion trajectory points coincide with the expected motion nodes; ⑥ Cladding machining: Perform cladding machining on the surface to be machined of the part to meet the technical requirements; in step ④: Before the detection probe moves, the protruding contact between it and the annular conductor always remains in contact, and the loop A2 is conducting;The detection probe approaches the part to be measured slowly. When the tip of the probe touches the surface of the part to be measured, circuit A2 is turned on and circuit A1 is turned on. After the control system receives this signal, the detection probe decelerates forward. After the tip is stressed, the protruding contact disengages from the ring conductor, circuit A2 is turned off and circuit A1 is turned on. After the control system receives this signal, the detection probe stops moving forward. The control system automatically reads the current position coordinate value of the device coordinate system and calculates the current position tool coordinate value according to the conversion instruction edited in the program, and automatically assigns it to the corresponding motion program trajectory node. At this time, the tip of the detection probe leaves the part, circuit A2 is turned off and circuit A1 is turned off. After the control system receives this signal, the detection probe retracts. When the protruding contact touches the ring conductor again, circuit A2 is turned on and circuit A1 is turned off. After the control system receives this signal, it stops retracting; then the above program is repeated to enter the next detection cycle, that is, the sequential execution of the "approach - contact - stop - retract" cycle detection program with a smaller level of movement distance until the measurement of the minimum feed unit specified by the programming is completed, which means the detection of one position is completed. The control system automatically reads the coordinate value of the current position relative to the device coordinate system, and obtains the coordinate value of the current position relative to the detection probe device coordinate system through conversion, and automatically assigns it to the corresponding motion program trajectory node, that is, calibrates the position of the part; then continues to perform the detection and calibration of the next position until the detection and calibration of the entire surface to be machined are completed; among them, the detection probe and the ring conductor form circuit A2, one end of the wire is connected to the tail of the probe and the other end is connected to the ring conductor: the detection probe and the part to be measured form circuit A1, one end of the wire is connected to the tail of the probe and the other end is connected to the part; the detection probe approaching the part to be measured is forward and away from the part to be measured is backward.

2. The method according to claim 1, characterized in that: The detection probe device further includes at least two O-ring rubber seals (6). There are at least two upper and lower annular grooves (1-1) provided on the inner wall of the small hole of the probe base (1). The O-ring rubber seals (6) are arranged in the annular grooves (1-1) and cooperate with the needle tip portion (2-3) of the detection probe (2).

3. The method according to claim 1, characterized in that: The detection probe device further includes a spring steel ball (7). The spring steel ball (7) is arranged in the transverse hole of the small outer circle of the quick connector (3), and its steel ball slightly protrudes from the small outer circle of the quick connector (3) in the free state.

4. The method according to claim 1, wherein: The detection probe device further includes a plurality of LED lighting sources (8). The LED lighting sources (8) are evenly distributed on the upper end surface of the cylindrical surface of the probe base (1).

5. The method according to claim 1, characterized in that: The detection probe device further includes a plurality of LED indicator lights (9). The LED indicator lights (9) are evenly distributed on the cylindrical surface of the probe base (1).

6. The method according to claim 1, characterized in that: The material of the probe base (1) is insulating engineering plastic.

7. The method according to claim 1, wherein in step ④: in the execution of the "approach - contact - stop - retreat" loop program, for each point, the movement feed unit used later is one order of magnitude smaller than the movement feed unit used in the previous time. By executing the step-by-step reduction of the interval distance unit, the accurate position of the quadrant point of the surface to be machined can be determined, that is, precise positioning is achieved; each detection at each point is calculated and assigned a value, and the subsequent assignment will overwrite the previous assignment. The coordinate value of the smallest interval distance unit detected at the last detection point is the measured point coordinate position of the part to be measured in the coordinate system of the automated processing equipment. This value is automatically recorded and calculated and assigned to the movement trajectory point of the processing program.

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