Cylindrical workpiece machine vision detection device and use method thereof

Abstract

The invention discloses a cylindrical workpiece machine vision detection device and a use method thereof, and belongs to the technical field of workpiece vision detection.The cylindrical workpiece machine vision detection device comprises a base, a first rotating mechanism, a second rotating mechanism, a jacking assembly, a vision detection position adjusting assembly and a light angle adjusting assembly; a jacking assembly is arranged at the top of the other opposite side of the base, a visual detection position adjusting assembly is arranged on the second rotating mechanism, a light angle adjusting assembly is arranged on the visual detection position adjusting assembly, and a to-be-detected cylindrical workpiece is clamped at the end of the first rotating mechanism. According to the invention, two detection methods can be integrated on the same machine, the detection requirements of different shaft parts are met, the load of the slewing mechanism is reduced, and the manufacturing cost of the slewing mechanism is reduced.

Description

Technical Field

[0001] This invention relates to the field of workpiece visual inspection technology, and in particular to a machine vision inspection device for cylindrical workpieces and its usage method. Background Technology

[0002] Shaft parts, as core basic components in mechanical transmission, precision manufacturing and other fields, are widely used in key equipment such as automotive engines, rail transit bearings, and aerospace gearboxes. Their surface quality directly determines the assembly accuracy, motion stability and service life of the equipment.

[0003] Machine vision technology, as a non-contact inspection technology, boasts advantages such as high speed, high accuracy, and good stability, and has been widely applied in industrial inspection. Early machine vision inspection primarily employed area scan cameras; however, area scan cameras suffer from an inherent contradiction between resolution and field of view when inspecting long-axis parts, making it difficult to simultaneously meet the requirements of inspection accuracy and coverage. Line scan cameras, on the other hand, scan pixel by pixel, stitching images together with the movement of the part. This solves the inspection coverage problem for long-axis parts and achieves high-precision inspection by increasing the density of individual pixels.

[0004] Existing methods for detecting surface defects in shaft-type parts based on line scan cameras involve a rotating mechanism connected to the part, which then rotates within the detection area. The line scan camera scans and acquires images of the part line by line in one direction according to a set frequency and resolution. An encoder monitors the movement of the part in real time, providing trigger signals to the camera to ensure accurate image acquisition and stitching.

[0005] If the part being inspected is a large shaft such as a wind turbine main shaft, the weight of the shaft can reach tens of tons, requiring a custom-made high-load, high-precision rotary drive mechanism. Its manufacturing cost is 5-10 times that of conventional small shaft inspection equipment. Moreover, during rotation, machining errors (such as end face runout and radial runout) can easily cause instantaneous speed instability, resulting in tensile or compressive deformation in image acquisition.

[0006] Therefore, those skilled in the art need to provide a machine vision inspection device for cylindrical workpieces and its usage method, which can design a vision inspection structure and method for large and small cylindrical workpieces on a single machine, meet the inspection needs of different shaft parts, reduce the load on the rotating mechanism, and reduce its manufacturing cost. Summary of the Invention

[0007] The purpose of this invention is to provide a machine vision inspection device for cylindrical workpieces and its usage method, which can integrate two inspection methods on the same machine, meet the inspection needs of different shaft parts, reduce the load on the rotary mechanism, and reduce its manufacturing cost.

[0008] To achieve the above objectives, the present invention provides a machine vision inspection device for cylindrical workpieces, comprising a base, a first rotating mechanism, a second rotating mechanism, a clamping assembly, a vision inspection position adjustment assembly, and a light angle adjustment assembly. The first rotating mechanism and the second rotating mechanism are disposed on the top of one side of the base, and the clamping assembly is disposed on the top of the opposite side of the base. The vision inspection position adjustment assembly is disposed on the second rotating mechanism, and the light angle adjustment assembly is disposed on the vision inspection position adjustment assembly. The end of the first rotating mechanism clamps the cylindrical workpiece to be inspected.

[0009] Preferably, the rotating mechanism includes a motor, a transmission shaft, a coupling sleeve, a bushing, a three-jaw chuck, and a jaw plate connecting shaft. The output end of the motor is connected to the transmission shaft. A groove is provided on the outer surface of the right end of the transmission shaft. The coupling sleeve has a hollow structure and a protrusion is provided inside the coupling sleeve. The coupling sleeve is slidably connected to the other end of the transmission shaft. The outer surface of the right end of the coupling sleeve is provided with a protrusion, and the left end of the bushing is provided with a groove. The right end of the coupling sleeve is embedded into the left end of the bushing and slidably connected. The right end of the claw disk connecting shaft is fixed to the three-jaw chuck, the middle part of the three-jaw chuck holds the cylindrical workpiece to be measured, and the left end of the claw disk connecting shaft is provided with a groove that matches the protrusion. When inspecting a small cylindrical workpiece, the coupling sleeve slides and the connecting shaft of the claw disc slides and then stops, and the coupling sleeve disengages from the shaft sleeve. When inspecting a large cylindrical workpiece, the coupling sleeve slides and the shaft sleeve, and then the coupling sleeve is limited and disengaged from the claw disc connecting shaft. The outer surface of the drive shaft is connected to the encoder via a gear assembly.

[0010] Preferably, the rotating mechanism two includes a shaft cylinder and an indexing plate. The claw plate connecting shaft is rotatably connected to the shaft cylinder through a bearing. The left end of the shaft cylinder is fixed to the right end of the bushing by bolts. The outer surface of the shaft cylinder is also provided with a bearing. The bearing cover limits the bearing on the outer surface of the shaft cylinder to the top of the left side of the base. The indexing plate is fixed to the right end of the shaft cylinder, and an arc-shaped groove is provided on the side wall of the indexing plate.

[0011] Preferably, the visual detection position adjustment component includes two slide rails, a first slider, a fixing plate, a screw, a second slider, a camera bracket, a line scan camera, and a line light source. The bottom end of one slide rail slides along the first arc groove and is fastened with bolts. The other slide rail is vertically arranged and its bottom is fastened to the indexing plate with bolts. Each of the slide rails is slidably connected to a slider, and a bolt passes through the slider and abuts against the slide rail to achieve fixation. Each of the first sliders is fixedly connected to a fixed plate at its right end, and fixed blocks are fixedly connected to both ends of the bottom of each fixed plate. The two ends of the screw are rotatably connected to the fixed blocks. The top of the second slider slides along the fixed plate. The middle part of the second slider is provided with a thread, and the second slider is threadedly connected to the screw. One slider has a camera bracket at its bottom, which holds a line scan camera; the other slider has a wired light source connected to its bottom via a light angle adjustment component.

[0012] Preferably, the light angle adjustment component includes a U-shaped bracket one and a U-shaped bracket two. The top of the U-shaped bracket one is fixed to the bottom of a slider two. A connecting block is fixed to the top of the U-shaped bracket two. A bolt passes through the connecting block and the side wall of the U-shaped bracket one for fixation. An arc-shaped groove two is provided on the side wall of the U-shaped bracket one. A bolt slides along the arc-shaped groove two and is fixed to the connecting block. A wired light source is connected between the two side walls of the U-shaped bracket two by bolts.

[0013] Preferably, the clamping assembly includes a pin, a sliding seat, a connecting shaft, and a handle. A groove is provided on the top right side of the base. One end of the connecting shaft is rotatably connected to the top right side of the base via a bearing. The other end of the connecting shaft is provided with a threaded section. The bottom of the sliding seat is threadedly connected to the threaded section. The center of the handle is fixed to one end of the connecting shaft. A pin is rotatably connected to the top of the sliding seat via a bearing. A conical groove is provided at one end of the cylindrical workpiece. The pin clamps against the conical groove of the cylindrical workpiece to be tested.

[0014] Preferably, it also includes a bushing fastening assembly and a pin fastening assembly. When testing a small cylindrical workpiece, the bushing fastening assembly will fasten the bushing and stop the bushing from rotating. The bushing fastening assembly includes two fixing plates. One end of each fixing plate is located on both sides of the plate body on the bushing and is in frictional contact. A fastening bolt fastens the two fixing plates together. The other end of the fixing plate is fixed to the top left side of the base. When inspecting a large cylindrical workpiece, the ejector pin fastening assembly will fasten the ejector pin and stop its rotation; The ejector pin fastening assembly includes an ejector pin tail seat located at the right end of the ejector pin. The ejector pin tail seat has evenly distributed ejector pin tail seat grooves. The fixing block engages with the ejector pin tail seat grooves, and the second fastening bolt fixes the bottom of the fixing block to the sliding seat.

[0015] A method for using a machine vision inspection device for cylindrical workpieces includes the following steps. Step 1, Equipment Assembly and Coaxial Calibration: Connect the cylindrical workpiece to be tested coaxially with the rotating mechanism through a three-jaw chuck, integrate the line scan camera and line light source to form a detection component, rigidly connect the detection component with the second rotating mechanism, and adjust the installation positions of the first rotating mechanism and the second rotating mechanism so that the center lines of their output shafts are collinear; Step 2, Parameter Adjustment: Adjust the height of the line scan camera from the surface of the cylindrical workpiece to be inspected so that the camera's field of view covers the inspection area; adjust the illumination angle of the line light source so that the illumination area of ​​the light source completely overlaps with the camera's field of view; start the image acquisition software and preset the image resolution, acquisition frame rate, and exposure time parameters. Step 3, Detection Mode Switching and Startup: Based on the outer diameter of the cylindrical workpiece to be tested, select the detection mode via the power switching mechanism: If the part is a large shaft part: the part is fixed by tooling fixtures, the power switching mechanism transmits the torque of the motor output shaft to the second rotating mechanism, driving the detection component to make a circular motion around the center line of the part, and starting scanning and image acquisition; If the part is a small shaft-type part: the fixed detection component, the power switching mechanism transmits the motor output shaft torque to the rotating mechanism one, driving the part to rotate around its own axis, and the line scan camera starts line-by-line scanning and image acquisition; Step 4, Synchronous Triggering and Image Stitching: An encoder is installed on the drive shaft. The encoder collects the rotation angle signal of the drive shaft in real time and uses it as the acquisition trigger signal for the line scan camera. After receiving the trigger signal, the line scan camera acquires images line by line. The image acquisition software stitches the single-line images into a complete circular image according to the encoder angle signal. Step 5, Segmented Scanning and Image Acquisition: Based on the length of the cylindrical workpiece to be tested, the cylindrical workpiece to be tested is divided into N detection segments along the axial direction, where N is a positive integer. After the detection component completes the scanning of the first detection segment, the screw and slider structure in the visual detection position adjustment component drives the detection component to move to the next detection segment. Step 4 is repeated until all detection segments are acquired. Step 6, Full Surface Image Stitching: The image acquisition software stitches together the annular images of N detection segments along the axial direction based on the axial movement distance of the detection components to form a complete unfolded image of the part surface, which is used for defect identification and analysis.

[0016] Preferably, the shooting angle of the line scan camera is perpendicular to the surface of the part and points to the axis of the part. The line light source adjusts the illumination direction through the light angle adjustment component to ensure that the illumination area of ​​the light source completely overlaps with the field of view of the camera, and the light intensity in the field of view is uniform and there are no shadows or overexposed areas. The encoder is connected to the drive shaft via a pair of gears. When the drive shaft rotates one revolution, the encoder triggers the line scan camera to complete the image acquisition of one revolution of the part surface, ensuring that the image acquisition is synchronized with the movement of the part or detection component.

[0017] Preferably, the defect recognition accuracy of the complete part surface unfolded image is ≤0.1mm, and the detection efficiency is ≥10 pieces / hour, which is suitable for the automated detection needs in industrial mass production scenarios.

[0018] The advantages and positive effects of the machine vision inspection device for cylindrical workpieces described in this invention are: This invention fixes large shaft-like parts, and a line scan camera and line light source scan and acquire images by rotating around the large cylindrical workpiece coaxially with a rotating assembly. For surface inspection of small cylindrical workpieces, the workpiece is still rotated within the inspection area by the rotating assembly, and the line scan camera scans and acquires images of the part line by line in one direction. Integrating these two inspection methods onto a single machine meets the inspection needs of different shaft-like parts, reduces the load on the rotating mechanism, and lowers its manufacturing cost.

[0019] With a power switching mechanism, the detection modes can be flexibly selected as "large shaft fixed, camera rotates around the shaft" or "small shaft rotates on its own, camera fixed". One system covers all shaft sizes, greatly improving equipment utilization. The coaxial design of the dual rotating mechanisms eliminates the need to drive heavy-duty large shafts, reducing the cost and installation space requirements of the rotating mechanism. At the same time, the standardized operation throughout the process adapts to the high-efficiency and stable detection needs of industrial mass production.

[0020] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of a machine vision inspection device for cylindrical workpieces according to the present invention. Figure 2 This is a schematic diagram from another perspective of the machine vision inspection device for cylindrical workpieces according to the present invention. Figure 3 This is a cross-sectional view of the rotating mechanism of the present invention at one location; Figure 4 This is a schematic diagram of the structure at the positions of the coupling sleeve and bushing of the present invention; Figure 5 This is a schematic diagram of the structure of the visual detection position adjustment component of the present invention; Figure 6 This is a schematic diagram of the light angle adjustment component of the present invention; Figure 7 This is a schematic diagram of the clamping component structure of the present invention; Figure 8 This is a schematic diagram of the connection structure of the coupling sleeve, bushing, and claw disc connecting shaft of the present invention; Figure 9 This is another perspective schematic diagram of the connection structure of the coupling sleeve, bushing and claw disc connecting shaft of the present invention; Figure 10 This is a schematic diagram of the coupling sleeve and claw disc connecting shaft structure of the present invention; Figure 11 This is a schematic diagram of the linear array camera, line light source, and cylindrical workpiece to be tested according to the present invention. Figure 12 This is a schematic diagram of the encoder and drive shaft of the present invention; Figure 13 This is a schematic diagram of the bushing fastening assembly structure of the present invention; Figure 14 This is a schematic diagram of the ejector pin fastening assembly structure of the present invention; Figure 15 This is a flowchart illustrating the method of using the present invention.

[0022] Figure Labels 1. Base; 2. Rotating Mechanism 1; 201. Motor; 202. Drive Shaft; 203. Encoder; 204. Coupling Sleeve; 205. Shaft Sleeve; 206. Reducer; 207. Three-jaw Chuck; 208. Jaw Disc Connecting Shaft; 209. Bearing Cover; 3. Rotating mechanism two; 301. Shaft cylinder; 302. Indexing plate; 3021. Arc groove one; 4. Tightening assembly; 401. Ejector pin; 402. Sliding seat; 403. Connecting shaft; 404. Threaded section; 405. Handle; 5. Visual inspection position adjustment assembly; 501. Slide rail; 502. Slider one; 503. Fixing plate; 504. Screw; 505. Slider two; 506. Camera bracket; 507. Line scan camera; 508. Line light source; 6. Light angle adjustment assembly; 601. U-shaped bracket one; 602. Arc groove two; 603. Bolt; 604. U-shaped bracket two; 605. Connecting block; 7. Cylindrical workpiece to be tested; 8. Bushing fastening assembly; 801. Fixing plate; 802. Fastening bolt one; 9. Ejector pin fastening assembly; 901. Ejector pin tail seat groove; 902. Fixing block; 903. Two fastening bolts. Detailed Implementation

[0023] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing the 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 the invention. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0024] In this application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. In case of any inconsistency, the meaning set forth in this specification or derived from the content described herein shall prevail. Furthermore, the terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit the scope of this application.

[0025] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0026] like Figures 1-15 As shown, a machine vision inspection device for cylindrical workpieces includes a base 1, a first rotating mechanism 2, a second rotating mechanism 3, a clamping assembly 4, a vision inspection position adjustment assembly 5, and a light angle adjustment assembly 6. The first rotating mechanism 2 and the second rotating mechanism 3 are arranged on the top of one side of the base 1, and the clamping assembly 4 is arranged on the top of the opposite side of the base 1. The vision inspection position adjustment assembly 5 is arranged on the second rotating mechanism 3, and the light angle adjustment assembly 6 is arranged on the vision inspection position adjustment assembly 5. The end of the first rotating mechanism 2 holds the cylindrical workpiece 7 to be inspected.

[0027] The rotating mechanism 2 includes a motor 201, a drive shaft 202, a coupling sleeve 204, a bushing 205, a three-jaw chuck 207, and a jaw disc connecting shaft 208. The output end of the motor 201 is connected to the drive shaft 202. A groove is provided on the outer surface of the right end of the drive shaft 202. The coupling sleeve 204 is a hollow structure with protrusions inside. The coupling sleeve 204 is slidably connected to the other end of the drive shaft 202. The protrusions match the grooves.

[0028] Specifically, the output end of the motor 201 is connected to the drive shaft 202 via the reducer 206.

[0029] The outer surface of the right end of the coupling sleeve 204 is provided with a protrusion, and the left end of the bushing 205 is provided with a groove. The right end of the coupling sleeve 204 is inserted into the left end of the bushing 205 and slidably connected. The protrusion and the groove match.

[0030] The right end of the jaw plate connecting shaft 208 is fixed to the three-jaw chuck 207. The middle part of the three-jaw chuck 207 holds the cylindrical workpiece 7 to be measured. The left end of the jaw plate connecting shaft 208 is provided with a groove that matches the protrusion.

[0031] When testing a small cylindrical workpiece 7, the coupling sleeve 204 slides and is limited after sliding with the claw disk connecting shaft 208, and the coupling sleeve 204 disengages from the bushing 205.

[0032] Specifically, when inspecting small shaft parts, the "small shaft rotation, camera fixed" inspection method is selected. The shaft sleeve 205 is clamped by a clamping mechanism to fix the entire rotating mechanism 23, thereby fixing the line scan camera 507 and the line light source 508. The coupling sleeve 204 slides and connects to the jaw chuck connecting shaft 208. The torque of the motor 201 sequentially drives the cylindrical workpiece to rotate through the reducer, drive shaft 202, coupling sleeve 204, jaw chuck connecting shaft 208, and three-jaw chuck 207.

[0033] When testing a large cylindrical workpiece 7, the coupling sleeve 204 and the bushing 205 slide and are then limited, and the coupling sleeve 204 disengages from the claw disc connecting shaft 208.

[0034] Specifically, when inspecting large cylindrical workpieces, the "large shaft fixed, camera rotates around the shaft" inspection method is selected. The position of the ejector pin 401 is adjusted using the clamping assembly 4, so that the ejector pin 401 is clamped to the end of the cylindrical workpiece, thereby fixing the shaft component. The coupling sleeve 204 slides and connects to the bushing. The torque of the motor 201 drives the line scan camera 507 and the line light source 508 to rotate around the surface of the shaft component through the reducer 206, drive shaft 202, coupling sleeve 204, bushing 205, indexing plate 302, slide rail 501, and lead screw slider module.

[0035] The outer surface of the drive shaft 202 is connected to the encoder 203 via a gear assembly.

[0036] The rotating mechanism 2 includes a shaft cylinder 301 and an indexing plate 302. The claw plate connecting shaft 208 is rotatably connected to the shaft cylinder 301 through a bearing. The left end of the shaft cylinder 301 is fixed to the right end of the bushing 205 by a bolt 603. The outer surface of the shaft cylinder 301 is also provided with a bearing. The bearing cover 209 limits the bearing on the outer surface of the shaft cylinder 301 to the top of the left side of the base 1.

[0037] The indexing plate 302 is fixed to the right end of the shaft cylinder 301, and an arc-shaped groove 3021 is provided on the side wall of the indexing plate 302.

[0038] The visual inspection position adjustment component 5 includes two slide rails 501, a first slider 502, a fixing plate 503, a screw 504, a second slider 505, a camera bracket 506, a line scan camera 507, and a line light source 508. The bottom end of one slide rail 501 slides along the arc groove 3021 and is fastened with bolts. The other slide rail 501 is vertically set and the bottom of the slide rail 501 is fastened to the indexing plate 302 with bolts.

[0039] Each slide rail 501 is slidably connected to a slider 502, and a bolt 603 passes through the slider 502 and abuts against the slide rail 501 to achieve fixation.

[0040] Each slider 502 has a fixed plate 503 fixedly connected to its right end. Each fixed plate 503 has a fixed block fixedly connected to both ends of its bottom. The two ends of the screw 504 are rotatably connected to the fixed blocks. The top of the slider 505 slides along the fixed plate 503. The middle part of the slider 505 is provided with a thread. The slider 505 is threadedly connected to the screw 504.

[0041] A camera bracket 506 is mounted on the bottom of one slider 2 505, and a line scan camera 507 is fixed to the camera bracket 506. The bottom of the other slider 2 505 is connected to a wired light source 508 via a light angle adjustment component 6.

[0042] The light angle adjustment component 6 includes a U-shaped bracket 1 601 and a U-shaped bracket 2 604. The top of the U-shaped bracket 1 601 is fixed to the bottom of a slider 2 505. A connecting block 605 is fixed to the top of the U-shaped bracket 2 604. A bolt 603 passes through the connecting block 605 and the side wall of the U-shaped bracket 1 601 for fixation. An arc groove 2 602 is provided on the side wall of the U-shaped bracket 1 601. After sliding along the arc groove 2 602, the bolt 603 is fixed to the connecting block 605. A wire light source 508 is connected between the two side walls of the U-shaped bracket 2 604 by bolt 603.

[0043] The clamping assembly 4 includes a pin 401, a sliding seat 402, a connecting shaft 403, and a handle 405. A groove is provided on the top right side of the base 1. One end of the connecting shaft 403 is rotatably connected to the top right side of the base 1 via a bearing. The other end of the connecting shaft 403 is provided with a threaded section 404. The bottom of the sliding seat 402 is threadedly connected to the threaded section 404. The center of the handle 405 is fixed to one end of the connecting shaft 403. The top of the sliding seat is rotatably connected to the pin 401 via a bearing. A conical groove is provided at one end of the cylindrical workpiece. The pin 401 clamps against the conical groove of the cylindrical workpiece to be measured.

[0044] It also includes a bushing fastening assembly 8 and a pin fastening assembly 9. When testing a small cylindrical workpiece, the bushing fastening assembly 8 will fasten the bushing 205 and stop the bushing 205 from rotating.

[0045] The bushing fastening assembly 8 includes two fixing plates 801. One end of the two fixing plates 801 is located on both sides of the plate body on the bushing and is in frictional contact. Fastening bolt 802 fastens the two fixing plates 801 together. The other end of the fixing plate 801 is fixed to the top of the left side of the base.

[0046] When inspecting a large cylindrical workpiece, the ejector pin fastening assembly 9 tightens the ejector pin 401, stopping its rotation. Because the ejector pin 401 holds the cylindrical workpiece in place, the workpiece also stops rotating and remains stationary.

[0047] The ejector pin fastening assembly 9 includes an ejector pin tail seat located at the right end of the ejector pin. The ejector pin tail seat has evenly distributed ejector pin tail seat grooves 901. The fixing block 902 engages with the ejector pin tail seat grooves 901. The fastening bolt 903 fixes the bottom of the fixing block 902 to the sliding seat.

[0048] The present invention discloses a method for using a machine vision inspection device for cylindrical workpieces, comprising the following steps: Step 1, Equipment Assembly and Coaxial Calibration: Connect the cylindrical workpiece to be tested coaxially with the rotating mechanism 1 2 via the three-jaw chuck 207. Integrate the line scan camera 507 and the line light source 508 to form a detection assembly. Rigidly connect the detection assembly to the rotating mechanism 2 3. Adjust the installation positions of the rotating mechanism 1 2 and the rotating mechanism 2 3 so that the center lines of their output shafts are collinear.

[0049] Step 2, Parameter Adjustment: Adjust the height of the line scan camera 507 from the surface of the cylindrical workpiece to be inspected, ensuring the camera's field of view covers the inspection area. Adjust the illumination angle of the line light source 508 so that the illuminated area completely overlaps with the camera's field of view. Start the image acquisition software and preset the image resolution, frame rate, and exposure time parameters.

[0050] Step 3, Detection Mode Switching and Startup: Based on the outer diameter of the cylindrical workpiece 7 to be tested, select the detection mode via the power switching mechanism: If the part is a large shaft: the part is fixed by tooling fixture, the power switching mechanism transmits the output shaft torque of motor 201 to the rotating mechanism 23, driving the detection component to make circular motion around the axis of the part, and start scanning and image acquisition. If the part is a small shaft part: the fixed detection component and the power switching mechanism transmit the output shaft torque of the motor 201 to the rotating mechanism 2, driving the part to rotate around its own axis, and the line scan camera 507 starts progressive scanning and image acquisition. Step 4, Synchronous Triggering and Image Stitching: An encoder 203 is installed on the drive shaft 202. The encoder 203 acquires the rotation angle signal of the drive shaft 202 in real time and uses it as the acquisition trigger signal for the line scan camera 507. After receiving the trigger signal, the line scan camera 507 acquires images line by line. The image acquisition software stitches the single-line images into a complete circular image based on the angle signal from the encoder 203. Step 5, Segmented Scanning and Image Acquisition: Based on the length of the cylindrical workpiece 7 to be tested, the cylindrical workpiece 7 to be tested is divided into N detection segments along the axial direction, where N is a positive integer. After the detection component completes the scanning of the first detection segment, the screw 504 slider structure in the visual detection position adjustment component 5 drives the detection component to move to the next detection segment. Step 4 is repeated until all detection segments are acquired. Step 6, Full Surface Image Stitching: The image acquisition software stitches together the annular images of N detection segments along the axial direction based on the axial movement distance of the detection components to form a complete unfolded image of the part surface, which is used for defect identification and analysis.

[0051] The shooting angle of the line scan camera 507 is perpendicular to the surface of the part and points to the axis of the part. The line light source 508 adjusts the illumination direction through the light angle adjustment component 6 to ensure that the illumination area of ​​the light source is completely superimposed on the field of view of the camera, and the light intensity in the field of view is uniform and there are no shadows or overexposed areas.

[0052] The encoder 203 is connected to the drive shaft 202 via a pair of gears. When the drive shaft 202 rotates one revolution, the encoder 203 triggers the line scan camera 507 to complete the image acquisition of one revolution of the part surface, ensuring that the image acquisition is synchronized with the movement of the part or detection component.

[0053] The defect recognition accuracy of the complete part surface unfolded image is ≤0.1mm, and the detection efficiency is ≥10 pieces / hour, which is suitable for the automated detection needs of industrial mass production scenarios.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A machine vision inspection device for cylindrical workpieces, characterized in that: The device includes a base, a first rotating mechanism, a second rotating mechanism, a clamping assembly, a vision inspection position adjustment assembly, and a light angle adjustment assembly. The first rotating mechanism and the second rotating mechanism are located on the top of one side of the base, and the clamping assembly is located on the top of the opposite side of the base. The second rotating mechanism is equipped with a vision inspection position adjustment assembly, and the vision inspection position adjustment assembly is equipped with a light angle adjustment assembly. The end of the first rotating mechanism holds the cylindrical workpiece to be tested.

2. The machine vision inspection device for cylindrical workpieces according to claim 1, characterized in that: The rotating mechanism includes a motor, a drive shaft, a coupling sleeve, a bushing, a three-jaw chuck, and a jaw disk connecting shaft. The output end of the motor is connected to the drive shaft. The outer surface of the right end of the drive shaft is provided with a groove. The coupling sleeve is a hollow structure and has protrusions inside. The coupling sleeve is slidably connected to the other end of the drive shaft. The outer surface of the right end of the coupling sleeve is provided with a protrusion, and the left end of the bushing is provided with a groove. The right end of the coupling sleeve is embedded into the left end of the bushing and slidably connected. The right end of the claw disk connecting shaft is fixed to the three-jaw chuck, the middle part of the three-jaw chuck holds the cylindrical workpiece to be measured, and the left end of the claw disk connecting shaft is provided with a groove that matches the protrusion. When inspecting a small cylindrical workpiece, the coupling sleeve slides and the connecting shaft of the claw disc slides and then stops, and the coupling sleeve disengages from the shaft sleeve. When inspecting a large cylindrical workpiece, the coupling sleeve slides and the shaft sleeve, and then the coupling sleeve is limited and disengaged from the claw disc connecting shaft. The outer surface of the drive shaft is connected to the encoder via a gear assembly.

3. The machine vision inspection device for cylindrical workpieces according to claim 2, characterized in that: The second rotating mechanism includes a shaft cylinder and an indexing plate. The claw plate connecting shaft is rotatably connected to the shaft cylinder through a bearing. The left end of the shaft cylinder is fixed to the right end of the bushing by bolts. The outer surface of the shaft cylinder is also provided with a bearing. The bearing cover limits the bearing on the outer surface of the shaft cylinder to the top of the left side of the base. The indexing plate is fixed to the right end of the shaft cylinder, and an arc-shaped groove is provided on the side wall of the indexing plate.

4. The machine vision inspection device for cylindrical workpieces according to claim 3, characterized in that: The visual detection position adjustment component includes two slide rails, slider one, a fixing plate, a screw, slider two, a camera bracket, a line scan camera and a line light source. The bottom end of one slide rail slides along the arc groove one and is then fastened with bolts. The other slide rail is set vertically and its bottom is fastened to the indexing plate with bolts. Each of the slide rails is slidably connected to a slider, and a bolt passes through the slider and abuts against the slide rail to achieve fixation. Each of the first sliders is fixedly connected to a fixed plate at its right end, and fixed blocks are fixedly connected to both ends of the bottom of each fixed plate. The two ends of the screw are rotatably connected to the fixed blocks. The top of the second slider slides along the fixed plate. The middle part of the second slider is provided with a thread, and the second slider is threadedly connected to the screw. One slider has a camera bracket at its bottom, which holds a line scan camera; the other slider has a wired light source connected to its bottom via a light angle adjustment component.

5. The machine vision inspection device for cylindrical workpieces according to claim 4, characterized in that: The light angle adjustment assembly includes a U-shaped bracket 1 and a U-shaped bracket 2. The top of the U-shaped bracket 1 is fixed to the bottom of a slider 2. A connecting block is fixed to the top of the U-shaped bracket 2. A bolt passes through the connecting block and the side wall of the U-shaped bracket 1 for fixation. An arc-shaped groove 2 is provided on the side wall of the U-shaped bracket 1. A bolt slides along the arc-shaped groove 2 and is fixed to the connecting block. A wired light source is connected between the two side walls of the U-shaped bracket 2 by bolts.

6. The machine vision inspection device for cylindrical workpieces according to claim 5, characterized in that: The clamping assembly includes a pin, a sliding seat, a connecting shaft, and a handle. A groove is provided on the top right side of the base. One end of the connecting shaft is rotatably connected to the top right side of the base via a bearing. The other end of the connecting shaft is provided with a threaded section. The bottom of the sliding seat is threadedly connected to the threaded section. The center of the handle is fixed to one end of the connecting shaft. A pin is rotatably connected to the top of the sliding seat via a bearing. A conical groove is provided at one end of the cylindrical workpiece. The pin clamps against the conical groove of the cylindrical workpiece to be tested.

7. The machine vision inspection device for cylindrical workpieces according to claim 6, characterized in that: It also includes a bushing fastening assembly and a pin fastening assembly. When testing a small cylindrical workpiece, the bushing fastening assembly will fasten the bushing and stop the bushing from rotating. The bushing fastening assembly includes two fixing plates. One end of each fixing plate is located on both sides of the plate body on the bushing and is in frictional contact. A fastening bolt fastens the two fixing plates together. The other end of the fixing plate is fixed to the top left side of the base. When inspecting a large cylindrical workpiece, the ejector pin fastening assembly will fasten the ejector pin and stop its rotation; The ejector pin fastening assembly includes an ejector pin tail seat located at the right end of the ejector pin. The ejector pin tail seat has evenly distributed ejector pin tail seat grooves. The fixing block engages with the ejector pin tail seat grooves, and the second fastening bolt fixes the bottom of the fixing block to the sliding seat.

8. A method of using the machine vision inspection device for cylindrical workpieces as described in any one of claims 1-7, characterized in that: Includes the following steps, Step 1, Equipment Assembly and Coaxial Calibration: Connect the cylindrical workpiece to be tested coaxially with the rotating mechanism through a three-jaw chuck, integrate the line scan camera and line light source to form a detection component, rigidly connect the detection component with the second rotating mechanism, and adjust the installation positions of the first rotating mechanism and the second rotating mechanism so that the center lines of their output shafts are collinear; Step 2, Parameter Adjustment: Adjust the height of the line scan camera from the surface of the cylindrical workpiece to be inspected so that the camera's field of view covers the inspection area; adjust the illumination angle of the line light source so that the illumination area of ​​the light source completely overlaps with the camera's field of view; start the image acquisition software and preset the image resolution, acquisition frame rate, and exposure time parameters. Step 3, Detection Mode Switching and Startup: Based on the outer diameter of the cylindrical workpiece to be tested, select the detection mode via the power switching mechanism: If the part is a large shaft part: the part is fixed by tooling fixtures, the power switching mechanism transmits the torque of the motor output shaft to the second rotating mechanism, driving the detection component to make a circular motion around the center line of the part, and starting scanning and image acquisition; If the part is a small shaft-type part: the fixed detection component, the power switching mechanism transmits the motor output shaft torque to the rotating mechanism one, driving the part to rotate around its own axis, and the line scan camera starts line-by-line scanning and image acquisition; Step 4, Synchronous Triggering and Image Stitching: An encoder is installed on the drive shaft. The encoder collects the rotation angle signal of the drive shaft in real time and uses it as the acquisition trigger signal for the line scan camera. After receiving the trigger signal, the line scan camera acquires images line by line. The image acquisition software stitches the single-line images into a complete circular image according to the encoder angle signal. Step 5, Segmented Scanning and Image Acquisition: Based on the length of the cylindrical workpiece to be tested, the cylindrical workpiece to be tested is divided into N detection segments along the axial direction, where N is a positive integer. After the detection component completes the scanning of the first detection segment, the screw and slider structure in the visual detection position adjustment component drives the detection component to move to the next detection segment. Step 4 is repeated until all detection segments are acquired. Step 6, Full Surface Image Stitching: The image acquisition software stitches together the annular images of N detection segments along the axial direction based on the axial movement distance of the detection components to form a complete unfolded image of the part surface, which is used for defect identification and analysis.

9. The method of using the machine vision inspection device for cylindrical workpieces according to claim 8, characterized in that: The shooting angle of the line scan camera is perpendicular to the surface of the part and points to the axis of the part. The line light source adjusts the irradiation direction through the light angle adjustment component to ensure that the irradiation area of ​​the light source is completely overlapped with the field of view of the camera, and the light intensity in the field of view is uniform and there are no shadows or overexposed areas. The encoder is connected to the drive shaft via a pair of gears. When the drive shaft rotates one revolution, the encoder triggers the line scan camera to complete the image acquisition of one revolution of the part surface, ensuring that the image acquisition is synchronized with the movement of the part or detection component.

10. The method of using the machine vision inspection device for cylindrical workpieces according to claim 8, characterized in that: The defect recognition accuracy of the complete unfolded image of the part surface is ≤0.1mm, and the detection efficiency is ≥10 pieces / hour, which is suitable for the automated detection needs in industrial mass production scenarios.

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