Surface defect detection device for parts of numerical control machine tool

Abstract

The invention belongs to the technical field of numerically-controlled machine tool part detection, and particularly relates to a numerically-controlled machine tool part surface defect detection device which comprises a bottom plate, a moving assembly, a distance adjusting assembly and a centering clamp, the moving assembly is arranged on the bottom plate, and the centering clamp is installed at the free end of the moving assembly. The top of the bottom plate is further fixedly connected with a mounting ring through a pair of supports, the shaft penetrates through the mounting ring, a plurality of visual probes capable of moving in the radial direction are arranged in the circumferential direction of the mounting ring, and the distance adjusting assembly is used for automatically adjusting the distance between the visual probes and the surface of the shaft according to the diameter of the shaft. According to the device, the distance adjusting assembly can automatically adjust the distance between the visual probe and the surface of the shaft according to the diameter of the shaft, manual intervention is not needed, shaft parts of different diameter specifications can be rapidly adapted, and the problems that traditional detection equipment needs to manually calibrate the distance and is poor in adaptability are solved.

Description

Technical Field

[0001] This invention relates to the field of CNC machine tool component inspection technology, and in particular to a surface defect detection device for CNC machine tool components. Background Technology

[0002] In the production of CNC machine tool parts, shaft parts are core transmission components, and their surface quality directly affects the operating accuracy and service life of CNC machine tools. Therefore, it is necessary to strictly inspect for defects such as cracks, scratches, and dents on the surface of shaft parts.

[0003] Currently, the traditional methods for surface defect inspection of shaft-type CNC machine tool parts mainly rely on manual visual inspection or fixed inspection equipment. Manual visual inspection is inefficient, greatly affected by the experience and subjective judgment of the inspectors, and is prone to missing small defects, and is difficult to adapt to the needs of mass production. For fixed inspection equipment, the distance between the vision element used to collect surface images and the surface of the shaft needs to be manually calibrated during the inspection process. If the distance is too close, it is easy to cause collision damage between the element and the shaft. If it is too far, it will cause the image to be blurred, directly affecting the inspection accuracy. Therefore, corresponding improvements have been made to address this problem. Summary of the Invention

[0004] Based on the technical problems existing in the prior art, the present invention proposes a surface defect detection device for CNC machine tool parts.

[0005] This invention proposes a surface defect detection device for CNC machine tool parts, comprising a base plate, a moving assembly, a distance adjustment assembly, and a centering fixture. The moving assembly is mounted on the base plate, and the centering fixture is mounted on the free end of the moving assembly. A mounting ring for a shaft to pass through is fixedly connected to the top of the base plate via a pair of brackets. Multiple radially movable vision probes are arranged circumferentially on the mounting ring. The distance adjustment assembly automatically adjusts the distance between the vision probes and the shaft surface according to the shaft diameter. The shaft is fixed by the centering fixture, and the moving assembly drives the centering fixture and the shaft to move, allowing the shaft to pass through the mounting ring. The distance adjustment assembly automatically adjusts the distance between each vision probe and the shaft surface according to the shaft diameter, ensuring that the vision probes can clearly capture images of the shaft surface, thereby achieving the detection of surface defects on the shaft.

[0006] Preferably, the moving assembly includes a fixed frame, a slide, a screw, a guide post, and a motor. The fixed frame is fixedly connected to the base plate. The screw and guide post are symmetrically rotatably connected inside the fixed frame. The slide is simultaneously fitted onto the screw and guide post and threadedly connected to the screw. A centering fixture is installed on the slide. The motor is fixedly connected to the end of the fixed frame and connected to the end of the screw via an output shaft. When the motor starts, it drives the screw to rotate. Since the slide is threadedly connected to the screw and fitted onto the guide post, under the guidance of the guide post, the slide moves linearly along the fixed frame, thereby driving the centering fixture and shaft installed on the slide to move, thus realizing the position adjustment of the shaft during the testing process.

[0007] Preferably, the centering fixture is a multi-jaw chuck; the shaft is placed in the multi-jaw chuck, and by operating the multi-jaw chuck, its multiple jaws move synchronously to clamp the shaft from different directions, thereby achieving centering and fixing of the shaft, ensuring that the shaft will not shift during the inspection process, and improving the accuracy of the inspection.

[0008] Preferably, the distance adjustment assembly includes a cylinder body 1, a piston 1, a cylinder body 2, a piston 2, and a gas distribution box. The cylinder body 2 is fixedly connected to the side of the multi-jaw chuck. The piston 2 is located inside the cylinder body 2, and the bottom end of the piston 2 is fixedly connected to one of the jaws of the multi-jaw chuck through a connecting plate. The cylinder body 2 is connected to the gas distribution box through a hose 1. The cylinder body 1 is connected to the corresponding gas distribution connector on the gas distribution box through hose 2. The piston 1 is located inside the cylinder body 1, and the vision probe is connected to the free end of the piston 1. When the jaws of the multi-jaw chuck clamp the shaft, the jaws drive the piston 2 to move inside the cylinder body 2 through the connecting plate. The liquid inside the cylinder body 2 enters the gas distribution box through the hose 1, and then enters each cylinder body 1 through the gas distribution connector and hose 2, pushing the piston 1 to move, thereby driving the vision probe to move radially, so as to achieve the purpose of automatically adjusting the distance between the vision probe and the surface of the shaft according to the diameter of the shaft.

[0009] Preferably, the vision probe is slidably connected to its respective slide rail via a slider, the slide rail is fixedly connected to the mounting ring, and the slider is fixedly connected to the free end of the piston. When the piston moves, it drives the slider to slide on the slide rail. Since the slide rail is fixedly connected to the mounting ring, the vision probe moves radially along the direction of the slide rail, ensuring the stability and accuracy of the vision probe's movement and ensuring that it can be precisely adjusted to a suitable distance from the surface of the shaft.

[0010] Preferably, the second hose is equipped with a flow regulating valve; by adjusting the flow regulating valve on the second hose, the flow rate of liquid entering each cylinder can be controlled, thereby adjusting the moving speed and distance of the piston, and realizing fine adjustment of the position of different vision probes to adapt to different detection needs and the actual situation of the shaft.

[0011] Preferably, the distance adjustment assembly includes a diameter acquisition module and a linear module. The diameter acquisition module is installed at the axial entrance of the mounting ring to measure the diameter of the shaft in real time. The vision probes are installed on the free ends of their respective linear modules, which are fixedly connected to the mounting ring. The control module calculates the target radial position of the vision probes based on the data from the diameter acquisition module, ensuring that the distance between the vision probes and the surface of the shaft remains ideal. When the shaft enters the mounting ring, the diameter acquisition module installed at the axial entrance measures the diameter of the shaft in real time and transmits the data to the control module. The control module calculates the target radial position of each vision probe based on the measurement data, and then controls each linear module to move the vision probes to the target position, keeping the distance between the vision probes and the surface of the shaft within the ideal range to ensure the detection effect.

[0012] Preferably, the output and input terminals of the diameter acquisition module are electrically connected to the input and output terminals of the control module, and the output terminal of the control module is electrically connected to the input terminal of the linear module. The diameter acquisition module transmits the measured shaft diameter data to the control module. After processing the data, the control module sends a control signal to the linear module. The linear module moves the vision probe according to the control signal, realizing automatic adjustment of the vision probe position. The entire process is automated through electrical connection, which improves the response speed and adjustment accuracy of the detection device.

[0013] Preferably, the control module calculates the target radial position of the vision probe based on the data from the diameter acquisition module, and the steps are as follows: Real-time detection: The diameter acquisition module measures the diameter of the shaft and the actual radius from the current vision probe to the center line in real time; Target position calculation: Set the ideal distance from the vision probe to the shaft surface; calculate the target radius from the vision probe to the shaft centerline; Adjustment amount calculation: Calculate the radial adjustment amount required for the vision probe; the control module generates a control signal to drive the linear module to move the vision probe based on the sign and magnitude of the radial adjustment amount.

[0014] Compared with the prior art, the present invention provides a surface defect detection device for CNC machine tool parts, which has the following advantages: 1. Automatically adapts to shaft diameter, improving adaptability: The distance adjustment component can automatically adjust the distance between the vision probe and the shaft surface according to the shaft diameter, without manual intervention. It can quickly adapt to shaft parts of different diameter specifications, solving the problems of traditional testing equipment that require manual distance calibration and have poor adaptability.

[0015] 2. High detection accuracy and strong stability: On the one hand, the cooperation between the slide rail and the slider ensures the smoothness of the radial movement of the vision probe; on the other hand, a dead zone threshold is set in the distance control to avoid frequent adjustments of the vision probe due to small diameter fluctuations. At the same time, through precise target position calculation, it is ensured that the vision probe always acquires images of the shaft surface at an ideal distance, thus improving detection accuracy.

[0016] 3. High degree of automation, improving inspection efficiency: From fixing the shaft and moving it to adjusting the distance of the vision probe, the entire inspection process is automated, greatly reducing manual operation and shortening the inspection cycle. It is suitable for high-efficiency inspection in mass production scenarios. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the first angle structure of a surface defect detection device for CNC machine tool parts according to Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the second angle structure of a surface defect detection device for CNC machine tool parts proposed in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the adjustment component structure of a surface defect detection device for CNC machine tool parts proposed in this invention; Figure 4 For the present invention Figure 3 A magnified structural diagram at point A; Figure 5 This is a schematic diagram of the overall structure of a surface defect detection device for CNC machine tool parts proposed in Embodiment 2 of the present invention.

[0018] In the diagram: 1. Base plate; 2. Centering fixture; 3. Bracket; 4. Mounting ring; 5. Vision probe; 6. Fixture; 7. Slide carriage; 8. Screw; 9. Guide column; 10. Motor; 11. Slide rail; 12. Slider; 13. Cylinder 1; 14. Piston 1; 15. Cylinder 2; 16. Piston 2; 17. Hose 1; 18. Gas distribution box; 19. Gas distribution connector; 20. Hose 2; 21. Claw; 22. Connecting plate; 23. Linear module; 24. Diameter acquisition module. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0020] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0021] Reference Figures 1-5 A surface defect detection device for CNC machine tool parts includes a base plate 1, a moving assembly, a distance adjustment assembly, and a centering fixture 2. The moving assembly is mounted on the base plate 1, and the centering fixture 2 is mounted on the free end of the moving assembly. The top of the base plate 1 is also fixedly connected to a mounting ring 4 through which a shaft passes by a pair of brackets 3. Multiple radially movable vision probes 5 are arranged in the circumferential direction of the mounting ring 4. The distance adjustment assembly is used to automatically adjust the distance between the vision probes 5 and the surface of the shaft according to the diameter of the shaft. In use, the shaft is fixed by the centering clamp 2. The moving component drives the centering clamp 2 and the shaft to move, so that the shaft passes through the mounting ring 4. The distance adjustment component automatically adjusts the distance between each vision probe 5 and the surface of the shaft according to the diameter of the shaft, so as to ensure that the vision probe 5 can clearly capture the surface of the shaft, thereby realizing the detection of surface defects of the shaft.

[0022] In this invention, the moving component includes a fixed frame 6, a slide 7, a screw 8, a guide post 9, and a motor 10. The fixed frame 6 is fixedly connected to the base plate 1. The screw 8 and the guide post 9 are symmetrically rotatably connected inside the fixed frame 6. The slide 7 is simultaneously sleeved on the screw 8 and the guide post 9 and threadedly connected to the screw 8. The centering clamp 2 is installed on the slide 7. The motor 10 is fixedly connected to the end of the fixed frame 6 and connected to the end of the screw 8 through an output shaft. When in use, the motor 10 starts and drives the screw 8 to rotate. Since the slide 7 is threadedly connected to the screw 8 and sleeved on the guide post 9, the slide 7 moves linearly along the fixed frame 6 under the guidance of the guide post 9, thereby driving the centering fixture 2 and shaft installed on the slide 7 to move, so as to realize the position adjustment of the shaft during the testing process.

[0023] In this invention, the centering clamp 2 is a multi-jaw chuck, such as a three-jaw chuck, a four-jaw chuck, etc. In use, the shaft is placed in the multi-jaw chuck. By operating the multi-jaw chuck, its multiple jaws 21 move synchronously to clamp the shaft from different directions, thereby centering and fixing the shaft and ensuring that the shaft will not shift during the inspection process, thus improving the accuracy of the inspection.

[0024] In Embodiment 1 of the present invention, the distance adjustment assembly includes a cylinder body 13, a piston 14, a cylinder body 2 15, a piston 2 16, and a gas distribution box 18. The cylinder body 2 15 is fixedly connected to the side of the multi-jaw chuck. The piston 2 16 is located inside the cylinder body 2 15, and the bottom end of the piston 2 16 is fixedly connected to one of the jaws 21 of the multi-jaw chuck through a connecting plate 22. The cylinder body 2 15 is connected to the gas distribution box 18 through a hose 17. The cylinder body 13 is connected to the corresponding gas distribution connector 19 on the gas distribution box 18 through a hose 20. The piston 14 is located inside the cylinder body 13, and the vision probe 5 is connected to the free end of the piston 14. In use, when the jaws 21 of the multi-jaw chuck clamp the shaft, the jaws 21 drive the piston 16 to move inside the cylinder 15 via the connecting plate 22. The liquid inside the cylinder 15 enters the gas distribution box 18 through the hose 17, and then enters each cylinder 13 through the gas distribution connector 19 and the hose 20, pushing the piston 14 to move, which in turn drives the vision probe 5 to move radially, so as to achieve the purpose of automatically adjusting the distance between the vision probe 5 and the surface of the shaft according to the diameter of the shaft.

[0025] In this invention, the vision probe 5 is slidably connected to its respective slide rail 11 via the slider 12, the slide rail 11 is fixedly connected to the mounting ring 4, and the slider 12 is fixedly connected to the free end of the piston 14. When in use, the piston 14 moves, causing the slider 12 to slide on the slide rail 11. Since the slide rail 11 is fixedly connected to the mounting ring 4, the vision probe 5 moves radially along the direction of the slide rail 11, ensuring the stability and accuracy of the movement of the vision probe 5 and ensuring that it can be precisely adjusted to a suitable distance from the surface of the shaft.

[0026] Furthermore, the second hose 20 of the present invention is equipped with a flow regulating valve; In use, the flow rate of liquid entering each cylinder 13 can be controlled by adjusting the flow regulating valve on the hose 20, thereby adjusting the moving speed and distance of the piston 14, and realizing fine adjustment of the position of different vision probes 5 to adapt to different detection needs and the actual situation of shaft components.

[0027] In Embodiment 2 of the present invention, the distance adjustment component includes a diameter acquisition module 24 and a linear module 23. The diameter acquisition module 24 is installed at the axial entrance of the mounting ring 4 to measure the diameter of the shaft in real time. The vision probes 5 are installed on the free ends of their respective linear modules 23. The linear modules 23 are fixedly connected to the mounting ring 4. The control module calculates the target radial position of the vision probes 5 based on the data from the diameter acquisition module 24 to ensure that the distance from the vision probes 5 to the surface of the shaft remains at an ideal value. It should be noted that the diameter acquisition module 24 can be a laser rangefinder (such as the LK-G5000 series) or other devices capable of measuring the diameter of shafts. The control module is an embedded controller (such as the STM32 series), which receives diameter data, calculates the target position of the vision probe 5, and controls the movement of the linear module 23. Therefore, the diameter acquisition module 24 and the control module are not specifically limited here and can be selected according to actual needs. In use, when the shaft enters the mounting ring 4, the diameter acquisition module 24 installed at the axial entrance measures the diameter of the shaft in real time and transmits the data to the control module. The control module calculates the target radial position of each vision probe 5 based on the measurement data, and then controls each linear module 23 to work, driving the vision probe 5 to move to the target position, so that the distance between the vision probe 5 and the surface of the shaft is kept within the ideal range, ensuring the detection effect.

[0028] In this invention, the output and input terminals of the diameter acquisition module 24 are electrically connected to the input and output terminals of the control module, and the output terminal of the control module is electrically connected to the input terminal of the linear module 23. In use, the diameter acquisition module 24 transmits the measured shaft diameter data to the control module. After processing the data, the control module sends a control signal to the linear module 23. The linear module 23 moves the vision probe 5 according to the control signal, realizing the automatic adjustment of the position of the vision probe 5. The whole process is automated through electrical connection, which improves the response speed and adjustment accuracy of the detection device.

[0029] Furthermore, in this invention, the control module calculates the target radial position of the vision probe 5 based on the data from the diameter acquisition module 24, as follows: Real-time detection: The diameter acquisition module 24 measures the diameter of the shaft in real time and records it as D (unit: mm); the actual radius from the current vision probe 5 to the center line is recorded as R_current (unit: mm), which is fed back by the encoder or position sensor of the linear module 23; Target position calculation: Let the ideal distance from vision probe 5 to the surface of the shaft be L_ideal (unit: mm, determined by the lens focal length, a constant); the target radius R_target from vision probe 5 to the center line of the shaft is calculated as: R_target = L_ideal + D / 2; Adjustment amount calculation: The radial adjustment amount ΔR required for vision probe 5 is calculated using the formula: ΔR = R_target − R_current; The control module generates a control signal to drive the linear module 23 to move vision probe 5 based on the sign and magnitude of ΔR. Additionally, it should be noted that to avoid frequent adjustments due to minor fluctuations, a dead zone threshold ΔR_threshold (e.g., 0.1mm) is set; when |ΔR| ≥ ΔR_threshold, the control module activates the linear module 23 for adjustment; otherwise, the status quo is maintained.

[0030] Working principle: Shaft fixing and movement: Fix the shaft with centering clamp 2, start the motor 10 in the moving assembly, the motor 10 drives the screw 8 to rotate, the slide 7 moves linearly along the fixed frame 6 under the guidance of the guide column 9, thereby driving the centering clamp 2 and the shaft to move, so that the shaft passes through the mounting ring 4; Visual probe distance adjustment (Example 1): When the jaws 21 of the multi-jaw chuck clamp the shaft, the piston 16 inside the cylinder 15 moves through the connecting plate 22. The liquid inside the cylinder 15 enters the gas distribution box 18 through the hose 17, and then enters the cylinder 13 through the gas distribution connector 19 and the hose 20, pushing the piston 14 to move, which in turn moves the visual probe 5 radially along the slider 12 on the slide rail 11, adjusting the distance between the visual probe 5 and the surface of the shaft. The flow regulating valve on the hose 20 can control the liquid flow rate and adjust the moving speed and distance of the piston 14. Vision probe distance adjustment (Example 2): The diameter acquisition module 24 at the axial entrance of the mounting ring 4 measures the diameter of the shaft in real time and records it as D. After receiving the diameter data, the control module, combined with the ideal distance L_ideal from the vision probe 5 to the surface of the shaft, calculates the target radius R_target from the vision probe 5 to the center line of the shaft using the formula "R_target=L_ideal+D / 2". Then, based on the actual radius R_current from the current center line of the vision probe 5 fed back by the linear module 23, the radial adjustment amount ΔR=R_target−R_current is calculated. When |ΔR|≥dead zone threshold ΔR_threshold, the control module drives the linear module 23 to move the vision probe 5 to the target position; when |ΔR|<ΔR_threshold, the current position of the vision probe 5 is maintained. Surface defect detection: The vision probe 5 continuously acquires images of the shaft surface during the shaft movement, and detects surface defects of the shaft through image analysis.

[0031] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A surface defect detection device for CNC machine tool parts, comprising a base plate (1), a moving assembly, an adjusting assembly, and a centering fixture (2), characterized in that, The moving component is set on the base plate (1), and the centering clamp (2) is installed on the free end of the moving component. The top of the base plate (1) is also fixedly connected to a mounting ring (4) through which the shaft passes by a pair of brackets (3). Multiple vision probes (5) that can move radially are arranged in the circumferential direction of the mounting ring (4). The distance adjustment component is used to automatically adjust the distance between the vision probe (5) and the surface of the shaft according to the diameter of the shaft.

2. The surface defect detection device for CNC machine tool parts according to claim 1, characterized in that, The moving assembly includes a fixed frame (6), a slide (7), a screw (8), a guide post (9), and a motor (10). The fixed frame (6) is fixedly connected to the base plate (1). The screw (8) and the guide post (9) are symmetrically rotatably connected inside the fixed frame (6). The slide (7) is simultaneously sleeved on the screw (8) and the guide post (9) and threadedly connected to the screw (8). The centering clamp (2) is installed on the slide (7). The motor (10) is fixedly connected to the end of the fixed frame (6) and connected to the end of the screw (8) through an output shaft.

3. The surface defect detection device for CNC machine tool parts according to claim 1, characterized in that, The centering clamp (2) is a multi-jaw chuck.

4. A surface defect detection device for CNC machine tool parts according to claim 3, characterized in that, The adjustable distance assembly includes a cylinder (13), a piston (14), a cylinder (15), a piston (16), and a gas distribution box (18). The cylinder (15) is fixedly connected to the side of the multi-jaw chuck. The piston (16) is located inside the cylinder (15), and the bottom end of the piston (16) is fixedly connected to one of the jaws (21) of the multi-jaw chuck through a connecting plate (22). The cylinder (15) is connected to the gas distribution box (18) through a hose (17). The cylinder (13) is connected to the corresponding gas distribution connector (19) on the gas distribution box (18) through a hose (20). The piston (14) is located inside the cylinder (13), and the vision probe (5) is connected to the free end of the piston (14).

5. A surface defect detection device for CNC machine tool parts according to claim 4, characterized in that, The vision probe (5) is slidably connected to its respective slide rail (11) via a slider (12). The slide rail (11) is fixedly connected to the mounting ring (4), and the slider (12) is fixedly connected to the free end of the piston (14).

6. A surface defect detection device for CNC machine tool parts according to claim 4, characterized in that, The second hose (20) is equipped with a flow regulating valve.

7. A surface defect detection device for CNC machine tool parts according to claim 1, characterized in that, The distance adjustment assembly includes a diameter acquisition module (24) and a linear module (23). The diameter acquisition module (24) is installed at the axial entrance of the mounting ring (4) to measure the diameter of the shaft in real time. The vision probes (5) are installed on the free ends of their respective linear modules (23). The linear modules (23) are fixedly connected to the mounting ring (4). The control module calculates the target radial position of the vision probes (5) based on the data from the diameter acquisition module (24) to ensure that the distance from the vision probes (5) to the surface of the shaft remains at an ideal value.

8. A surface defect detection device for CNC machine tool parts according to claim 7, characterized in that, The output and input terminals of the diameter acquisition module (24) are electrically connected to the input and output terminals of the control module, and the output terminal of the control module is electrically connected to the input terminal of the linear module (23).

9. A surface defect detection device for CNC machine tool parts according to claim 7, characterized in that, The control module calculates the target radial position of the vision probe (5) based on the data from the diameter acquisition module (24), and the steps are as follows: Real-time detection: The diameter acquisition module (24) measures the diameter of the shaft in real time and measures the actual radius from the current vision probe (5) to the center line; Target position calculation: Set the ideal distance from the vision probe (5) to the surface of the shaft; calculate the target radius from the vision probe (5) to the center line of the shaft; Adjustment amount calculation: Calculate the radial adjustment amount required for the vision probe (5); the control module generates a control signal based on the sign and magnitude of the radial adjustment amount to drive the linear module (23) to move the vision probe (5).

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