A machine vision-based turbocharger part quality detection device

Abstract

The application belongs to the technical field of detection equipment, and particularly relates to a turbocharger part quality detection equipment based on machine vision, which comprises a workbench, a PLC controller, a CCD vision camera, a vision detection host and a display, the bottom ends of the PLC controller and the vision detection host are fixedly connected with the upper surface of the bottom plate of the workbench. The detection equipment has the functions of closed light-proof imaging, inclined rotary scanning, air pressure linkage angle adjustment and active dustproof protection, effectively solves the problem that the metal surface of the thrust bearing is easy to overexpose and cover the superficial defects, solves the problem that the longitudinal shadow of the thrust bearing flow guide groove leads to missed detection, the equipment can realize the dead angle-free vision detection of the end face and the flow guide groove of the thrust bearing, effectively improves the defect recognition accuracy and detection efficiency, replaces manual visual detection to reduce human error and labor intensity, stably guarantees the outgoing quality of the thrust bearing, and further improves the reliability of the whole turbocharger operation.

Description

Technical Field

[0001] This invention belongs to the field of testing equipment technology, and in particular relates to a quality testing device for turbocharger parts based on machine vision. Background Technology

[0002] The turbocharger is the core supercharging component of the internal combustion engine intake system. It relies on the exhaust gases from the engine to drive the turbine rotor to rotate at high speed, simultaneously driving the compressor impeller to compress the intake air. This effectively increases engine power density and reduces fuel consumption and emissions, and is widely used in the power systems of passenger cars, commercial vehicles, and construction machinery. The manufacturing quality of turbocharger components directly determines the overall engine performance and service life. Visual quality inspection is a core aspect of factory quality control. Existing machine vision-based turbocharger component quality inspection equipment primarily focuses on large, core components such as the turbine impeller, compressor impeller, and intermediate housing, often simplifying or completely ignoring the specialized visual inspection of small, precision auxiliary components like thrust bearings. Thrust bearings are mostly annular thin metal structures with multiple sets of guide grooves evenly distributed on one end face. They are assembled between the turbine shaft and the end face of the intermediate body and mainly bear the axial load of the rotor system and limit the axial movement clearance. At the same time, they transport lubricating oil through the guide grooves to form a load-bearing oil film. Defects such as scratches, bumps, sand holes and groove defects on the end face will directly destroy the stability of the oil film and accelerate the axial wear rate.

[0003] Currently, the appearance quality inspection of thrust bearings mainly uses two modes: general visual inspection station and manual visual sampling. Both have obvious shortcomings in quality control. Existing general machine vision inspection solutions mostly use a CCD vision camera to shoot vertically from the top. The inspection process is easily affected by external ambient light. Combined with the high reflectivity of the thrust bearing's metal surface, local overexposure is prominent when using conventional diffused surface light imaging. This can easily mask superficial defects such as minor scratches and pitting, directly leading to inaccurate inspection results. At the same time, the guide channel has a narrow and deep structure. Under the vertical shooting angle from the top, the channel wall and bottom will form a deep shadow, making it difficult to completely capture defects such as bumps and missing parts inside the channel, which can easily lead to missed inspections. After the parts with hidden defects are installed, they can cause oil film rupture and increased axial movement under the high-speed operation of the turbocharger, reducing the reliability of the turbocharger operation.

[0004] Manual visual inspection has drawbacks such as slow inspection speed and large judgment error. The inspection of a single piece takes a long time, which is difficult to match the pace of batch production lines. Moreover, the inspection results are greatly affected by the experience of the personnel and the degree of visual fatigue. The rate of missed detection and misjudgment fluctuates significantly, and it is impossible to reliably guarantee the quality of batch products.

[0005] To address these issues, we propose a machine vision-based quality inspection device for turbocharger parts. Summary of the Invention

[0006] The purpose of this invention is to address the above-mentioned problems by providing a machine vision-based quality inspection device for turbocharger parts.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a machine vision-based turbocharger parts quality inspection device, comprising a worktable, a PLC controller, a CCD vision camera, a vision inspection host, and a display. The bottom ends of the PLC controller and the vision inspection host are fixedly connected to the upper surface of the base plate of the worktable. A U-shaped top plate is fixedly connected to the upper surface of the worktable. A first electric push rod is fixedly embedded at the top of the U-shaped top plate. A circular hole is opened on the upper surface of the U-shaped top plate, and a U-shaped rod is slidably connected to the wall of the circular hole. The rod wall of the U-shaped rod is fixedly connected to the moving end of the first electric push rod.

[0008] A top cover is fixedly connected to one end of the U-shaped rod, and a light shield is fixedly connected to the lower surface of the top cover. An auxiliary mechanism is movably sleeved on the outer wall of the other end of the U-shaped rod, and the outer wall of the auxiliary mechanism is fixedly connected to the outer wall of the U-shaped top plate.

[0009] A visual inspection mechanism is fixedly connected to the inner wall of the light shield;

[0010] Both outer walls of the light shield are fixedly connected with sealing and dustproof mechanisms for the protection of CCD vision cameras.

[0011] A rotary drive mechanism is fixedly connected to the top of the light shield;

[0012] The upper surface of the workbench is fixedly connected to a component positioning seat by bolts.

[0013] In the aforementioned machine vision-based quality inspection equipment for turbocharger parts, the vision inspection mechanism includes a rectangular plate fixedly connected to the inner wall of a light shield. The upper surface of the rectangular plate has a through-hole, and a sealed bearing is fixedly connected to the wall of the through-hole. A fixing plate is fixedly connected to the inner wall of the inner ring of the sealed bearing. A first side plate and a second side plate are fixedly connected to the lower surface of the fixing plate. An arc-shaped guide plate is fixedly connected to the outer walls of the first and second side plates. A U-shaped frame is movably sleeved on the outer wall of the arc-shaped guide plate. An annular shadowless diffused light source is fixedly sleeved on the outer wall of the U-shaped frame. An opening is provided on the outer wall of the U-shaped frame that corresponds to the arc-shaped guide plate. The U-shaped frame has a uniform curvature and a movable hole. The inner wall of the U-shaped frame is fixedly connected to the top of the CCD vision camera. A cylinder is fixedly connected to the outer wall of the first side plate. A circular hole is opened on the outer wall of the first side plate, and a rubber rod is slidably connected to the hole wall. A support block is fixedly connected to the rubber rod on one side of the cylinder. A sealing ring is fixedly sleeved on the outer wall of the support block and slidably connected to the inner wall of the cylinder. The outer end of the rubber rod is fixedly connected to the outer wall of the U-shaped frame. A return spring is fixedly connected to the inner wall of the cylinder and the outer wall of the support block. A metal bend is fixedly connected to the outer wall of the side end of the cylinder. The top end of the metal bend passes through the upper surface of the fixed plate.

[0014] In the aforementioned machine vision-based turbocharger component quality inspection equipment, the sealing and dustproof mechanism includes a second electric push rod fixedly embedded in the side wall of the light shield. The outer wall of the light shield has a strip-shaped hole, and an L-shaped sealing plate is movably connected to the hole wall. The side wall of the L-shaped sealing plate is in sealed sliding contact with the inner wall of the light shield. The moving end of the second electric push rod is fixedly connected to the outer wall of the vertical part of the L-shaped sealing plate. A touch switch is fixedly connected to the bottom inner wall of the light shield.

[0015] In the aforementioned machine vision-based turbocharger component quality inspection equipment, the rotary drive mechanism includes a miniature servo motor fixedly connected to the upper surface of the light shield. The output end of the miniature servo motor passes through the inner wall of the top of the light shield and is fixedly connected to a drive gear. The inner wall of the inner ring of the sealed bearing is fixedly connected to an internal gear ring that meshes with the drive gear. The upper surface of the light shield is provided with a vent hole, which connects the internal cavity of the top cover with the top cavity of the light shield.

[0016] In the aforementioned machine vision-based turbocharger component quality inspection equipment, the auxiliary mechanism includes an air cylinder fixedly connected to the outer wall of a U-shaped top plate. A sealing plug is slidably connected to the inner wall of the air cylinder. The upper surface of the sealing plug is fixedly connected to the end of the U-shaped rod away from the top cover. A sliding through hole that mates with the outer wall of the U-shaped rod is opened at the top of the air cylinder. A branch pipe is fixedly connected to the top of the air cylinder. The outlet end of the branch pipe is fixedly connected to the inner wall of the bottom end of a light shield. A normally closed solenoid valve is fixedly connected to the bottom end of the air cylinder. A delivery pipe is fixedly connected to the outlet end of the normally closed solenoid valve. The outlet end of the delivery pipe is fixedly connected to the inner wall of the top cover. An expandable rubber blind tube is fixedly connected to the inner wall of the bottom end of the air cylinder. The sealed end of the expandable rubber blind tube is fixedly connected to the outer wall of the air cylinder.

[0017] In the aforementioned machine vision-based turbocharger parts quality inspection equipment, the inner wall of the top air inlet of the air cylinder is threaded, and a one-way air intake filter can is sealed to the wall of the threaded hole.

[0018] In the aforementioned machine vision-based turbocharger component quality inspection equipment, the upper surface of the light shield is provided with a fixed through hole and a circular hole for the output end of a micro servo motor to pass through, and a conductive slip ring is fixedly connected to the wall of the fixed through hole.

[0019] In the aforementioned machine vision-based turbocharger parts quality inspection equipment, the side wall of the display is fixedly connected to the outer wall of the U-shaped top plate, and a control switch is fixedly connected to the outer wall of the U-shaped top plate.

[0020] Compared with existing technologies, the advantages of a machine vision-based turbocharger parts quality inspection device are:

[0021] 1. By using a light shield, a ring-shaped shadowless diffused light source, and a component positioning seat, when inspecting the appearance quality of a turbocharger thrust bearing, the operator places the workpiece to be inspected on the component positioning seat for precise positioning. The first electric push rod drives the U-shaped rod to move vertically downward, pushing the bottom of the light shield to fit tightly against the surface of the worktable, so that the thrust bearing is completely enclosed in a light-shielding space, isolating it from interference from ambient light during the imaging process. At the same time, the ring-shaped shadowless diffused light source is activated, outputting uniform and soft diffused illumination light to weaken the appearance of the thrust bearing's metal surface. The specular reflection effect, followed by the CCD vision camera being in a vertical position for preliminary quality inspection of thrust bearings, solves the problem that existing general vision inspection equipment is easily affected by ambient light in the workshop, and the high reflectivity of the thrust bearing metal leads to local overexposure, which masks shallow surface defects such as minor scratches, pits, and pinholes, resulting in insufficient accuracy of inspection results. It can provide a stable and controllable imaging environment for vision inspection, avoid the negative impact of stray light and glare on image quality, significantly improve the identification accuracy of small shallow surface defects, and ensure the accuracy of thrust bearing end face appearance inspection results.

[0022] 2. Through the set visual inspection mechanism and rotary drive mechanism, after the initial vertical quality inspection of the thrust bearing end face is completed, the normally closed solenoid valve opens to release the pre-stored compressed air, driving the rubber rod to extend and push the U-shaped frame to slide and deflect along the arc-shaped guide plate. This causes the CCD vision camera to adjust from a vertical state to an inclined shooting angle. At the same time, the micro servo motor drives the inner ring of the sealed bearing and the fixed plate to rotate synchronously through the meshing transmission of the drive gear and the internal gear ring. This causes the inclined CCD vision camera to make a circular motion around the central axis of the workpiece. The conductive slip ring ensures stable power supply and signal transmission during the rotation process and avoids cable tangling. This structure solves the problem that under the existing vertical shooting method, the narrow and deep part of the thrust bearing guide groove is prone to forming a shadow area, and hidden defects such as groove wall bumps and groove shape defects cannot be effectively captured, resulting in blind spots and high missed detection rates. It can cover the entire inspection area of ​​the end face plane and the inner wall of the guide groove without dead angles, completely capture various surface defects and hidden defects in the groove, comprehensively improve the comprehensiveness and accuracy of the thrust bearing appearance quality inspection, and effectively ensure the operational reliability of the entire turbocharger.

[0023] 3. Through the auxiliary mechanism and sealing dustproof mechanism, when the equipment completes the inspection process with the U-shaped rod, the U-shaped rod synchronously drives the sealing plug to slide back and forth in the air cylinder. During the descent, the compressed air at the bottom of the air cylinder realizes air pressure energy storage, providing a power source for the angle deflection of the CCD vision camera, without the need for an additional independent air pump device. During the ascent, the clean air purified by the one-way air intake air filter canister at the top of the air cylinder is injected into the light shield through the branch pipe to form a positive air curtain barrier. After the inspection is completed, the second electric push rod drives the L-shaped sealing plate to close in opposite directions, sealing the CCD vision camera inside the light shield. This prevents the lens of the CCD vision camera from being in contact with the outside air for a long time and thus adhering to impurities, effectively protecting the inspection lens, extending the service life of the equipment, and greatly improving the inspection efficiency and quality stability of batch workpieces. At the same time, the fully automated inspection process replaces the traditional manual visual sampling inspection, solving the problems of slow manual inspection speed, large discrimination error, significant fluctuation in the rate of missed detection and false judgment, and difficulty in matching the cycle time of batch production lines. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a machine vision-based quality inspection device for turbocharger parts provided by the present invention;

[0025] Figure 2 yes Figure 1 A cross-sectional structural diagram;

[0026] Figure 3 yes Figure 2 A partially enlarged structural diagram of the visual inspection mechanism;

[0027] Figure 4 yes Figure 3 A cross-sectional structural diagram of the middle cylindrical section;

[0028] Figure 5 yes Figure 3 A schematic diagram of the three-dimensional structure of a rectangular plate;

[0029] Figure 6 yes Figure 3 A three-dimensional structural diagram of the arc-shaped guide plate;

[0030] Figure 7 yes Figure 3 A schematic diagram of the structure after the CCD vision camera is deflected.

[0031] In the diagram: 1. Workbench; 2. PLC controller; 3. CCD vision camera; 4. Vision inspection host; 5. Monitor; 6. Auxiliary mechanism; 61. Air cylinder; 62. Sealing plug; 63. Branch pipe; 64. Normally closed solenoid valve; 65. Delivery pipe; 66. Expandable rubber blind pipe; 7. Vision inspection mechanism; 71. Rectangular plate; 72. Through hole; 73. Sealed bearing; 74. Fixing plate; 75. First side plate; 76. Second side plate; 77. Arc-shaped guide plate; 78. U-shaped frame; 79. Annular shadowless diffused light source; 710. Cylinder; 711. 712. Rubber rod; 713. Support block; 714. Sealing ring; 715. Return spring; 716. Metal bend; 8. Sealing and dustproof mechanism; 81. Second electric push rod; 82. L-shaped sealing plate; 83. Touch switch; 9. Rotary drive mechanism; 91. Micro servo motor; 92. Drive gear; 93. Internal gear ring; 94. Vent hole; 10. U-shaped top plate; 11. First electric push rod; 12. U-shaped rod; 13. Top cover; 14. Light shield; 15. Parts positioning seat; 16. One-way air intake filter canister; 17. Conductive slip ring; 18. Control switch. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] like Figures 1-7As shown, a machine vision-based turbocharger parts quality inspection device includes a worktable 1, a PLC controller 2, a CCD vision camera 3, a vision inspection host 4, and a display 5. The bottom ends of the PLC controller 2 and the vision inspection host 4 are fixedly connected to the upper surface of the base plate of the worktable 1. A U-shaped top plate 10 is fixedly connected to the upper surface of the worktable 1. A first electric push rod 11 is fixedly embedded at the top of the U-shaped top plate 10. A circular hole is opened on the upper surface of the U-shaped top plate 10, and a U-shaped rod 12 is slidably connected to the wall of the circular hole. The rod wall of the U-shaped rod 12 is fixedly connected to the moving end of the first electric push rod 11. A top cover 13 is fixedly connected to one side of the U-shaped rod 12, and a light shield 14 is fixedly connected to the lower surface of the top cover 13. An auxiliary mechanism 6 is movably sleeved on the outer wall of the other end of the U-shaped rod 12. The outer wall of the auxiliary mechanism 6 is fixedly connected to the outer wall of the U-shaped top plate 10. The auxiliary mechanism 6 includes components connected to the U-shaped top plate 10. A cylinder 61 is fixedly connected to the outer wall of the cylinder 61. A sealing plug 62 is slidably connected to the inner wall of the cylinder 61. The upper surface of the sealing plug 62 is fixedly connected to the end of the U-shaped rod 12 away from the top cover 13. A sliding through hole that matches the outer wall of the U-shaped rod 12 is opened at the top of the cylinder 61. A branch pipe 63 is fixedly connected to the top of the cylinder 61. The outlet end of the branch pipe 63 is fixedly connected to the inner wall of the bottom end of the light shield 14. A normally closed solenoid valve 64 is fixedly connected to the bottom end of the cylinder 61. A delivery pipe 65 is fixedly connected to the outlet end of the normally closed solenoid valve 64. The outlet end of the delivery pipe 65 is fixedly connected to the inner wall of the top cover 13. An expandable rubber blind tube 66 is fixedly connected to the inner wall of the bottom end of the cylinder 61. The sealed end of the expandable rubber blind tube 66 is fixedly connected to the outer wall of the cylinder 61. At this time, the open end of the expandable rubber blind tube 66 is connected to the cavity inside the cylinder 61, so that the expandable rubber blind tube 66 can expand and store energy when receiving compressed air.

[0034] A visual inspection mechanism 7 is fixedly connected to the inner wall of the light shield 14. The visual inspection mechanism 7 includes a rectangular plate 71 fixedly connected to the inner wall of the light shield 14. The upper surface of the rectangular plate 71 has a through circular hole 72. A sealing bearing 73 is fixedly connected to the wall of the through circular hole 72. A fixing plate 74 is fixedly connected to the inner wall of the inner ring of the sealing bearing 73. A first side plate 75 and a second side plate 76 are fixedly connected to the lower surface of the fixing plate 74. An arc-shaped guide plate 77 is fixedly connected to the outer walls of the first side plate 75 and the second side plate 76. A U-shaped frame 78 is movably sleeved on the outer wall of the arc-shaped guide plate 77. An annular shadowless diffuse light source 79 is fixedly sleeved on the outer wall of the U-shaped frame 78. A moving hole with the same curvature as the arc-shaped guide plate 77 is opened on the outer wall of the U-shaped frame 78. The inner wall of the U-shaped frame 78 is fixedly connected to the top of the CCD vision camera 3. The outer wall of the first side plate 75 is fixedly connected to a cylinder 710. The outer wall of the first side plate 75 has a circular hole, and a rubber rod 711 is slidably connected to the hole wall. A support block 712 is fixedly connected to the rubber rod 711 on one side of the cylinder 710. A sealing ring 713 is fixedly sleeved on the outer wall of the support block 712 and is slidably connected to the inner wall of the cylinder 710. The outer end of the rubber rod 711 is fixedly connected to the outer wall of the U-shaped frame 78. A return spring 714 is fixedly connected to the inner wall of the cylinder 710 and the outer wall of the support block 712. A metal bend 715 is fixedly connected to the outer wall of the side end of the cylinder 710. The top end of the metal bend 715 passes through the upper surface of the fixing plate 74.

[0035] Both outer walls of the light shield 14 are fixedly connected to sealing and dustproof mechanisms 8 for protecting the CCD vision camera 3. The sealing and dustproof mechanism 8 includes a second electric push rod 81 fixedly embedded in the side wall of the light shield 14. The outer wall of the light shield 14 has a strip-shaped hole, and the wall of the strip-shaped hole is movably connected to an L-shaped sealing plate 82. The side wall of the L-shaped sealing plate 82 is in sealed sliding contact with the inner wall of the light shield 14. The moving end of the second electric push rod 81 is fixedly connected to the outer wall of the vertical part of the L-shaped sealing plate 82. A touch switch 83 is fixedly connected to the inner wall of the bottom end of the light shield 14.

[0036] A rotary drive mechanism 9 is fixedly connected to the top of the light shield 14. The rotary drive mechanism 9 includes a micro servo motor 91 fixedly connected to the upper surface of the light shield 14. The output end of the micro servo motor 91 passes through the inner wall of the top of the light shield 14 and is fixedly connected to a drive gear 92. An internal gear ring 93 that meshes with the drive gear 92 is fixedly connected to the inner wall of the inner ring of the sealed bearing 73. A vent hole 94 is provided on the upper surface of the light shield 14. The vent hole 94 connects the internal cavity of the top cover 13 with the top cavity of the light shield 14.

[0037] The upper surface of the workbench 1 is fixedly connected to the component positioning seat 15 by bolts. The component positioning seat 15 can achieve precise positioning during the testing of the thrust bearing, ensuring the accuracy of the test results.

[0038] The inner wall of the air inlet at the top of the air cylinder 61 is threaded, and the threaded hole wall is sealed with a one-way air filter canister 16. The upper surface of the light shield 14 is provided with a fixed through hole and a round hole for the output end of the micro servo motor 91 to pass through. The hole wall of the fixed through hole is fixedly connected with a conductive slip ring 17. The side wall of the display 5 is fixedly connected to the outer wall of the U-shaped top plate 10. The outer wall of the U-shaped top plate 10 is fixedly connected with a control switch 18.

[0039] The second electric push rod 81, the annular shadowless diffuse light source 79, the normally closed solenoid valve 64, the micro servo motor 91, and the first electric push rod 11 are also electrically connected to the output terminal of the PLC controller 2 via wires. The control switch 18 and the contact switch 83 are electrically connected to the input terminal of the PLC controller 2 via wires. Moreover, the circuits of the CCD vision camera 3 and the annular shadowless diffuse light source 79 are relayed through the conductive slip ring 17. The conductive slip ring 17 can prevent the wires from getting tangled during rotation, ensuring the reliability of the circuit. The above-mentioned electrical components and electrical connections are all existing technologies and will not be described in detail here.

[0040] The operating principle of this invention is described as follows: When turbocharger parts need to be visually inspected, the CCD vision camera 3 is first connected to the vision inspection host 4, and the display 5 is simultaneously connected to the vision inspection host 4. After the overall wiring and debugging of the equipment is completed, it can be put into use. Then, the operator places the thrust bearing to be inspected on the component positioning seat 15 to complete the precise positioning, ensuring that the end face to be inspected with the guide groove is facing upwards. Then, the start button of the control switch 18 is pressed, and the control switch 18 sends a start electrical signal to the PLC controller 2.

[0041] After receiving the start signal, the PLC controller 2 synchronously controls the first electric push rod 11 and the ring shadowless diffuse light source 79 to be powered on and started. The ring shadowless diffuse light source 79 is lit up and outputs uniform and soft diffuse light to weaken the mirror reflection of the metal surface.

[0042] The moving end of the first electric push rod 11 retracts, driving the U-shaped rod 12 to move vertically downward along the circular hole of the U-shaped top plate 10. The U-shaped rod 12 simultaneously drives the top cover 13 and the light shield 14 to move downward until the bottom end of the light shield 14 is tightly attached to the upper surface of the worktable 1, so that the thrust bearing is completely within the closed space of the light shield 14, completely isolating the interference of external ambient light on imaging. This solves the problems of ambient light interference, overexposure of metal surfaces covering up fine scratches, pits and other shallow surface defects in existing general visual inspection, and provides a stable dark field imaging environment for subsequent visual inspection, effectively improving imaging quality and the recognition accuracy of small defects.

[0043] At the same time, as the U-shaped rod 12 moves downward, it drives the sealing plug 62 of the auxiliary mechanism 6 to slide down synchronously along the inner wall of the air cylinder 61. The upper cavity of the air cylinder 61 draws in outside air through the one-way air intake filter canister 16. After being filtered and purified by the filter element, the air enters the low-pressure cavity above the air cylinder 61. The air in the lower cavity of the air cylinder 61 is compressed by the sealing plug 62. Some of the compressed air enters the expandable rubber blind tube 66 to expand and store pressure, which stores the air pressure power for the subsequent angle deflection of the CCD vision camera 3. There is no need to configure an additional independent air pump device, which simplifies the overall structure of the equipment and reduces manufacturing costs and maintenance difficulties.

[0044] When the bottom of the light shield 14 contacts the upper surface of the workbench 1, the touch switch 83 of the sealing and dustproof mechanism 8 is triggered by the reverse pressure of the workbench 1 surface. The touch switch 83 sends a position feedback signal to the PLC controller 2. After receiving the position signal, the PLC controller 2 controls the moving ends of the two second electric push rods 81 to extend synchronously, pushing the two L-shaped sealing plates 82 to move outward along the strip hole on the side wall of the light shield 14, releasing the obstruction of the lower space of the light shield 14, ensuring that the field of view of the CCD vision camera 3 is unobstructed, and ensuring that the detection field of view is complete and without blind spots.

[0045] At this time, the CCD vision camera 3 is directly above the thrust bearing. Under the uniform illumination of the annular shadowless diffuse light source 79, it vertically captures the upper end face of the thrust bearing, acquiring end face image information. The acquired image data is transmitted to the vision inspection host 4 in real time. The vision inspection host 4 has a built-in image preprocessing module, defect feature extraction module, and defect classification and judgment module. It first performs preprocessing such as noise reduction and contrast enhancement on the original image, and then uses a preset defect feature comparison algorithm to match and identify surface defects such as scratches, bumps, and sand holes on the end face, completing the preliminary vertical inspection of the end face. After the preset vertical inspection time (e.g., 3 seconds) ends, the PLC controller 2 synchronously sends a start command to the rotary drive mechanism 9 and the normally closed solenoid valve 64.

[0046] After the normally closed solenoid valve 64 is energized and opened, the compressed air pre-stored in the lower cavity of the air cylinder 61 enters the inner cavity of the top cover 13 along the delivery pipe 65, and then flows into the top cavity of the light shield 14 through the vent hole 94. The top cavity of the light shield 14 is sealed and isolated from the external environment by the rectangular plate 71, the sealed bearing 73 and the fixing plate 74, thus preventing air leakage. Subsequently, it is delivered to the inside of the cylinder 710 of the vision inspection mechanism 7 through the metal bend pipe 715. The compressed air pushes the support block 712 to slide outward along the inner wall of the cylinder 710, and at the same time causes the return spring 714 to extend and generate a restoring force. Block 712 will cause the rubber rod 711 to extend outward; the rubber rod 711 pushes the U-shaped frame 78 to slide and deflect along the arc of the arc guide plate 77, so that the CCD vision camera 3 fixed on the U-shaped frame 78 is adjusted from the vertical state to the tilt shooting angle, and the guide groove of the thrust bearing is photographed from an oblique perspective. This eliminates the shadow area that is easy to be generated in the narrow and deep part of the guide groove when shooting vertically, and solves the problem that defects such as bumps and damage in the groove are easily blocked by shadows and missed. At the same time, it can realize the visual inspection of the end face of the thrust bearing and the guide groove, effectively improve the defect identification accuracy and inspection efficiency, and replace manual visual inspection to reduce human error and labor intensity.

[0047] At the same time, the micro servo motor 91 is powered on and started, and its output end drives the drive gear 92 to rotate. Through gear meshing, the internal gear ring 93 rotates synchronously, and the internal gear ring 93 drives the inner ring of the sealed bearing 73 to rotate together. The inner ring of the sealed bearing 73 drives the fixed plate 74 to rotate. The fixed plate 74 drives the arc guide plate 77 and the tilted CCD vision camera 3 to rotate around the thrust bearing central axis through the first side plate 75 and the second side plate 76. During the rotation, the power supply and signal cables of the CCD vision camera 3 and the annular shadowless diffuse light source 79 are stably transmitted in the rotating state through the conductive slip ring 17 to avoid the cables from getting tangled and knotted, and to ensure the continuous and stable operation of the rotation detection process.

[0048] The tilted CCD vision camera 3 continuously acquires images during rotation, enabling full-circumference and full-angle scanning inspection of the thrust bearing end face and guide channel without blind spots. It can completely capture hidden defects such as channel wall collisions and channel shape defects, significantly reducing the probability of missed detection and comprehensively improving the accuracy and reliability of inspection. During the inspection, the vision inspection host 4 processes the acquired image data in real time. If an unqualified defect is identified, the defect location, defect type, and other information are immediately transmitted to the PLC controller 2 and the display 5. The display 5 provides a real-time visual display of the inspection results and defect details, making it convenient for staff to view intuitively. This structure improves the comprehensiveness and accuracy of the equipment's visual quality inspection of turbocharger thrust bearings.

[0049] When the preset full-angle detection time (e.g., 30 seconds) ends, the PLC controller 2 controls the extension of the moving end of the first electric push rod 11 and simultaneously controls the retraction of the moving end of the second electric push rod 81. The first electric push rod 11 then drives the U-shaped rod 12 to move upward. At this time, the pressure in the lower cavity of the air cylinder 61 is gradually released. Under the elastic force of the return spring 714, the support block 712 drives the rubber rod 711 to retract and reset. The U-shaped frame 78 slides back to the initial position along the arc-shaped guide plate 77, and the CCD vision camera 3 returns to the vertical shooting state. Subsequently, the normally closed solenoid valve 64 is de-energized and closed. The air passage is cut off. As the U-shaped rod 12 continues to move upward, the filtered clean air in the upper cavity of the air cylinder 61 is squeezed by the sealing plug 62 and injected into the light shield 14 through the branch pipe 63. This positively replaces the air in the light shield 14, forming an airflow barrier from the inside out. This prevents dust and impurities in the outside air from entering the light shield 14 and adhering to the lens surface of the CCD vision camera 3. This avoids the lens of the CCD vision camera 3 from being contaminated during the waiting time for the thrust bearing to be replaced, ensuring stable imaging quality under long-term use and improving the reliability of the equipment.

[0050] When the moving end of the first electric push rod 11 is fully extended and the light shield 14 is raised and reset, the moving end of the second electric push rod 81 is also fully retracted, causing the two L-shaped sealing plates 82 to move towards each other and dock with each other, sealing the lower opening of the light shield 14, so that the CCD vision camera 3 is in a closed and isolated dustproof environment, further improving the lens protection effect, reducing the frequency of daily cleaning and maintenance, and extending the service life of the equipment. Finally, the staff removes the thrust bearing that has been inspected from the component positioning seat 15 and replaces it with the next workpiece to be inspected. Repeating the above process can realize the continuous automated inspection of batch workpieces.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A machine vision-based quality inspection device for turbocharger parts, comprising a workbench (1), a PLC controller (2), a CCD vision camera (3), a vision inspection host (4), and a display (5), wherein the bottom ends of the PLC controller (2) and the vision inspection host (4) are fixedly connected to the upper surface of the base plate of the workbench (1), characterized in that, The upper surface of the workbench (1) is fixedly connected to a U-shaped top plate (10), and a first electric push rod (11) is fixedly embedded at the top of the U-shaped top plate (10). A round hole is opened on the upper surface of the U-shaped top plate (10), and a U-shaped rod (12) is slidably connected to the wall of the round hole. The rod wall of the U-shaped rod (12) is fixedly connected to the moving end of the first electric push rod (11). A top cover (13) is fixedly connected to one side of the U-shaped rod (12), and a light shield (14) is fixedly connected to the lower surface of the top cover (13). An auxiliary mechanism (6) is movably sleeved on the outer wall of the other end of the U-shaped rod (12), and the outer wall of the auxiliary mechanism (6) is fixedly connected to the outer wall of the U-shaped top plate (10). The inner wall of the light shield (14) is fixedly connected to a visual inspection mechanism (7). Both sides of the outer wall of the light shield (14) are fixedly connected with sealing and dustproof mechanisms (8) for the protection of the CCD vision camera (3). The top of the light shield (14) is fixedly connected to a rotary drive mechanism (9). The upper surface of the workbench (1) is fixedly connected to a component positioning seat (15) by bolts. The auxiliary mechanism (6) includes an air cylinder (61) fixedly connected to the outer wall of the U-shaped top plate (10). The inner wall of the air cylinder (61) is slidably connected to a sealing plug (62). The top end of the air cylinder (61) is fixedly connected to a branch pipe (63). The bottom end of the air cylinder (61) is fixedly connected to a normally closed solenoid valve (64). The outlet end of the normally closed solenoid valve (64) is fixedly connected to a delivery pipe (65). The inner wall of the bottom end of the air cylinder (61) is fixedly connected to an expandable rubber blind pipe (66). The sealing and dustproof mechanism (8) includes a second electric push rod (81) fixedly embedded in the side wall of the light shield (14). The outer wall of the light shield (14) is provided with a strip hole, and the wall of the strip hole is movably connected to an L-shaped sealing plate (82). The bottom inner wall of the light shield (14) is fixedly connected to a touch switch (83). The visual inspection mechanism (7) includes a rectangular plate (71) fixedly connected to the inner wall of the light shield (14). The upper surface of the rectangular plate (71) is provided with a through circular hole (72). A sealed bearing (73) is fixedly connected to the wall of the through circular hole (72). A fixed plate (74) is fixedly connected to the inner wall of the inner ring of the sealed bearing (73). A first side plate (75) and a second side plate (76) are fixedly connected to the lower surface of the fixed plate (74). An arc-shaped guide plate (77) is fixedly connected to the outer walls of the first side plate (75) and the second side plate (76). A U-shaped frame (78) is movably sleeved on the outer wall of the arc-shaped guide plate (77). A moving hole with the same curvature as the arc-shaped guide plate (77) is opened on the outer wall of the U-shaped frame (78). The inner wall of the U-shaped frame (78) is fixedly connected to the top of the CCD visual camera (3). The rotary drive mechanism (9) includes a micro servo motor (91) fixedly connected to the upper surface of the light shield (14). The output end of the micro servo motor (91) passes through the inner wall of the top of the light shield (14) and is fixedly connected to a drive gear (92). The inner ring of the sealed bearing (73) is fixedly connected to an internal gear ring (93) that meshes with the drive gear (92). The upper surface of the light shield (14) is provided with a vent hole (94). The vent hole (94) connects the internal cavity of the top cover (13) with the top cavity of the light shield (14). The upper surface of the sealing plug (62) is fixedly connected to the end of the U-shaped rod (12) away from the top cover (13).

2. The machine vision-based turbocharger component quality inspection equipment according to claim 1, characterized in that, The visual inspection mechanism (7) further includes an annular shadowless diffuse light source (79) fixedly sleeved with the outer wall of the U-shaped frame (78). A cylinder (710) is fixedly connected to the outer wall of the first side plate (75). A circular hole is opened on the outer wall of the first side plate (75), and a rubber rod (711) is slidably connected to the hole wall. A support block (712) is fixedly connected to one side of the cylinder (710). A sealing ring (713) is fixedly sleeved on the outer wall of the support block (712) and slidably connected to the inner wall of the cylinder (710). The outer end of the rubber rod (711) is fixedly connected to the outer wall of the U-shaped frame (78). A return spring (714) is fixedly connected to the inner wall of the cylinder (710) and the outer wall of the support block (712). A metal bend (715) is fixedly connected to the outer wall of the side end of the cylinder (710). The top end of the metal bend (715) passes through the upper surface of the fixed plate (74).

3. The machine vision-based quality inspection equipment for turbocharger parts according to claim 1, characterized in that, The side wall of the L-shaped sealing plate (82) is in sealed sliding contact with the inner wall of the light shield (14), and the moving end of the second electric push rod (81) is fixedly connected to the outer wall of the vertical part of the L-shaped sealing plate (82).

4. The machine vision-based quality inspection equipment for turbocharger parts according to claim 1, characterized in that, The top of the air cylinder (61) is provided with a sliding through hole that matches the outer wall of the U-shaped rod (12). The air outlet of the branch pipe (63) is fixedly connected to the inner wall of the bottom end of the light shield (14). The air outlet of the delivery pipe (65) is fixedly connected to the inner wall of the top cover (13). The sealing end of the expandable rubber blind tube (66) is fixedly connected to the outer wall of the air cylinder (61).

5. The machine vision-based quality inspection equipment for turbocharger parts according to claim 4, characterized in that, The top air inlet of the air cylinder (61) has a threaded hole on the inner wall, and the threaded hole wall is sealed with a one-way air filter canister (16).

6. The machine vision-based quality inspection equipment for turbocharger parts according to claim 3, characterized in that, The upper surface of the light shield (14) is provided with a fixed through hole and a round hole for the output end of the micro servo motor (91) to pass through, and a conductive slip ring (17) is fixedly connected to the hole wall of the fixed through hole.

7. The machine vision-based quality inspection equipment for turbocharger parts according to claim 1, characterized in that, The side wall of the display (5) is fixedly connected to the outer wall of the U-shaped top plate (10), and a control switch (18) is fixedly connected to the outer wall of the U-shaped top plate (10).

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