A casting inner wall defect detection device with an endoscopic probe

Abstract

The application relates to the field of visual detection equipment, in particular to a cast inner wall defect detection device with an endoscopic probe, which comprises a detection base, a pushing frame is fixedly installed on one side of the detection base, a supporting frame is fixedly installed on the other side of the detection base, a three-dimensional electric translation table is installed in the pushing frame, an optical detection tube is connected with the three-dimensional electric translation table, and the inside of the optical detection tube is a multi-joint snake bone-shaped structure. The detection shell which can be telescopically moved is used in cooperation with the protective shell, the detection shell is collected in the protective shell in the process that the optical detection tube is inserted into the inner cavity of the cast, lens directly collides with the inner wall of the cast is avoided, when the optical detection tube is moved to the detection position, the detection shell is pushed out of the protective shell through the unfolding assembly, the visual sensor is completely exposed, complete and unobstructed detection visual angles are obtained, and the problem that the existing protection scheme cannot consider both wear protection and detection visual angles is solved.

Description

Technical Field

[0001] This invention relates to the field of visual inspection equipment, specifically to a device for detecting defects in the inner wall of castings with an endoscopic probe. Background Technology

[0002] In the casting production process, many castings are often designed with complex internal structures such as deep cavities and long holes. These internal areas are extremely hidden, with narrow and tortuous spaces, making it difficult for traditional non-destructive testing methods such as ultrasonic and X-ray inspections to effectively reach and fully cover them. To effectively solve this technical bottleneck, it is necessary to develop a specialized inspection device that can flexibly bend and penetrate deep into the casting's internal cavity, and simultaneously acquire multi-dimensional, high-precision defect information. An optical inspection tube based on a multi-jointed serpentine mechanical structure is an effective solution to this problem; this inspection tube, combined with high-precision... The three-dimensional electric translation stage, working in conjunction with a user-friendly drive handle, controls the optical inspection tube to meander into the complex cavities inside the casting along a biomimetic serpentine path, flexibly bypassing deep cavities, blind holes, and various internal obstacles. However, in practical applications, it has been found that when the optical inspection tube with a common structure penetrates deep into the casting for detection, the precision optical lens mounted at its front end is prone to frequent scratches and collisions with the rough or irregular inner surface of the casting, resulting in severe wear, scratches, or even damage to the lens surface. This significantly affects the reliability and service life of the entire endoscopic probe inspection equipment. Simply adding an external rigid protective cover or sleeve to physically protect the lens, while avoiding direct collisions, significantly limits the lens's field of view and inspection angle. Furthermore, the more stringent the protective measures, the greater the restriction on the lens's angle of view, ultimately reducing the overall efficiency and defect detection capability of the inspection device, creating a contradiction between protection and performance.

[0003] To address this, a device for detecting defects in the inner wall of castings with an endoscopic probe is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a casting inner wall defect detection device with an endoscopic probe, in order to solve the problem that when using an external rigid protective cover for physical protection, the more stringent the protection measures are, the greater the restriction on the lens angle, which ultimately reduces the working efficiency and defect detection capability of the entire detection device, creating a contradiction between protection and performance.

[0005] To achieve the above objectives, the present invention provides the following technical solution: An internal defect detection device for castings with an endoscopic probe includes a detection base, a pusher fixedly mounted on one side of the detection base, and a support frame fixedly mounted on the other side of the detection base. A three-dimensional electric translation stage is installed inside the pusher, and an optical detection tube is connected to the three-dimensional electric translation stage. The optical detection tube has a multi-jointed serpentine structure inside, and its outer wall is provided with spiral patterns. A drive handle connected to the optical detection tube is installed inside the pusher. A protective shell is installed at one end of the optical detection tube, and a detection shell is installed inside the protective shell. A vision sensor is installed in the middle of the detection shell, and multiple LED patch light sources are arranged in a ring around the vision sensor. Laser projection structures are provided on both sides of the vision sensor. An unfolding assembly is installed inside the protective shell and is connected to the detection shell. When the detection shell moves to a designated position, the unfolding assembly pushes the detection shell out of the protective shell.

[0006] In the casting production process, many castings have deep cavities and elongated holes in their inner walls. These areas are hidden and difficult to cover using conventional flaw detection methods. A detection device that can flexibly bend and penetrate deep into the inner cavity while acquiring multi-dimensional defect information is needed to solve this problem. This can be achieved by using a multi-jointed, serpentine optical inspection tube. A three-dimensional electric translation stage, combined with a drive handle, allows the optical inspection tube to enter the casting in a serpentine manner, bypassing deep cavities and elongated holes. However, in common optical inspection tubes, the lens at the front end collides with the inside of the casting over a long period, causing severe wear and significantly impacting the lifespan of the endoscopic probe inspection equipment. Using a protective cover... When protecting the lens of an endoscopic probe, it affects the detection angle. The tighter the protection, the greater the impact on the angle. Therefore, this invention uses a retractable and movable detection shell in conjunction with a protective shell. This allows the detection shell to be retracted inside the protective shell while the optical detection tube is inserted into the casting cavity, preventing the lens from directly rubbing against and colliding with the casting's inner wall, reducing unnecessary wear, and extending the equipment's lifespan. Once the optical detection tube is moved to the detection position, the detection shell is pushed out of the protective shell via an unfolding component, fully exposing the vision sensor, LED patch light source, and laser projection structure, obtaining a complete and unobstructed detection angle. This does not hinder the defect detection process and solves the problem of existing protection schemes being unable to simultaneously address wear protection and the detection angle. Furthermore, existing methods for inspecting the inner walls of deep-cavity, long-hole castings mostly rely on vision sensors to capture images of the inner wall for defect identification. However, due to limitations in the lighting conditions and imaging dimensions within the cavity, the accuracy in identifying shallow pits, surface micro-cracks, and other defects is low. This device adds laser projection structures on both sides of the vision sensor, which can work in conjunction with the vision sensor to obtain depth and contour information of defects, further improving the accuracy of defect detection and identification.

[0007] Preferably, the unfolding assembly includes a connecting column, one end of which is fixedly installed to an optical detection tube, and the other end of which is connected to a detection housing. The connecting column and the optical detection tube are installed via a connecting block. The protective housing is slidably connected to the connecting column, and a pushing ring is slidably connected to the connecting column. The pushing ring is disposed inside the protective housing. A main steel wire is fixedly installed on the side of the pushing ring away from the detection housing. The main steel wire is disposed inside the optical detection tube and connected to a drive handle. A rubber protective sleeve is fitted on the connecting column, and both ends of the rubber protective sleeve are fixedly installed to the connecting block and the protective housing, respectively.

[0008] In practical use, the entire device is first fixed to the port of the casting to be inspected using a support frame, so that the optical detection tube can be aligned with the inner cavity opening of the casting. Then, according to the inspection requirements, the optical detection tube is inserted into the casting. By pulling the steel wire with the drive handle, the optical detection tube, due to its multi-jointed serpentine structure, can bend and adjust adaptively with the direction of the inner wall of the casting. With the help of the three-dimensional electric translation stage to adjust the overall feed position, the detection shell with the detection element at the end can be sent into the designated detection position on the inner wall of the casting. After reaching the detection position, the drive handle pulls the main steel wire, pushing the ring to continue moving the protective shell towards the connecting block. The detection shell remains in a fixed position under the positioning of the connecting column, allowing the detection shell to extend out from the protective shell. Then, the vision sensor, LED patch light source, and laser projection structure are activated to perform imaging inspection on the inner wall of the casting, obtaining information on the location and size of defects on the inner wall. After the inspection is completed, the drive handle pushes the main steel wire, the protective shell resets, and the detection shell is re-covered. Then, the optical detection tube is pulled out from the inner cavity of the casting.

[0009] Preferably, the connecting column has a mounting hole, the detection housing is rotatably connected to the mounting hole, the detection housing is generally semi-elliptical, a roller is fixedly installed on the rotating shaft of the detection housing, a push bar is fixedly installed inside the protective housing, the push bar abuts against the roller when it moves to a designated position, the push bar is generally trapezoidal and long, and the push bar is generally made of spring steel.

[0010] In practical use, the operator aligns the pusher with the inner wall opening of the casting to be inspected. By manipulating the drive handle, the optical detection tube, along with its protective housing, is slowly fed into the inner wall of the casting. Once the device reaches the inspection position, the operator pulls the main steel wire, which in turn moves the push ring along the connecting post towards the detection housing. The push ring pushes the protective housing to slide on the connecting post, causing the rubber protective sleeve to stretch and unfold. As the protective housing moves, the internally fixed push bar gradually approaches the roller. When the protective housing pushes the detection housing out slightly, the push bar comes into contact with the roller, and the trapezoidal push bar pushes the roller... The rotation of the wheel causes the semi-elliptical detection housing to rotate, automatically adjusting its angle after extending out of the protective housing. This allows the detection housing to rotate upwards by 90°, aligning the internal vision sensor with the surface to be inspected on the inner wall of the casting. Subsequently, the surrounding LED patch light source and the laser projection structures on both sides are activated, working in conjunction with the vision sensor to acquire image information of the inner wall of the casting, completing the defect detection operation. After the inspection is completed, the main steel wire releases its thrust, the rubber protective sleeve retracts and springs back, causing the protective housing to reset. The detection housing then retracts back into the protective housing, allowing the device to be extracted from the casting, completing the entire inspection process.

[0011] Preferably, the protective shell has multiple evenly arranged elongated grooves, the entire elongated groove having an L-shaped structure. A supporting plate is provided inside the elongated groove. One side of the supporting plate is rotatably connected to the elongated groove, and the other side of the supporting plate has an arc-shaped cross-section. A rubber protective film is fixedly installed between the supporting plate and the protective shell. When the supporting plate is in its original position, it is inclined and abuts against a pushing ring on one side. The side of the pushing ring away from the detection shell is arc-shaped. A magnet is provided on one side of the elongated groove, and the magnet is fixedly installed on the connecting column. The magnet attracts the supporting plate.

[0012] The optical detection tube, which uses a multi-jointed serpentine structure, will bend and deform at a certain angle after its detection shell is removed. At this time, the end of the newly pushed-out detection shell is prone to direct collision with the inner wall of the casting, causing friction and damage to the transparent protective cover installed at the end of the detection shell. If it is operated and used in this state for a long time, it will seriously affect the service life and stability of the entire optical detection equipment. Therefore, in order to effectively avoid the collision between the detection shell and the inner wall of the casting when it is pushed out, the design adopts a supporting long plate to provide auxiliary support for the detection shell, so that it can be stably kept in the middle position of the internal space of the casting during the pushing process, without contacting the surrounding inner wall.

[0013] In operation, the main steel wire pulls the ring to one side, causing it to abut against multiple inclined support plates. Since the support plates are initially inclined, the ring gradually unfolds them as it moves until their ends abut against the inner wall of the casting, forming a stable support structure. Simultaneously, as the ring continues to move forward, the inspection shell is smoothly pushed out without deviation or collision. A magnet is installed on one side of the long slot, which attracts the support plates. Combined with the rubber protective film covering the surface of the support plates, as the ring pushes out and returns to its original position, the support plates can smoothly return to their initial inclined position with the help of the elastic restoring force of the rubber protective film. The magnet then attracts and fixes the support plates after they are reset, ensuring their stability in non-working states, thus preparing them for the next inspection operation.

[0014] Preferably, the supporting plate includes a fixed plate and a rotating plate. The fixed plate has a rotating groove on one side, and the rotating groove has an inclined surface on one side, with the inclined direction being upward. The rotating plate is rotatably connected in the rotating groove, and one side of the rotating plate cooperates with the inclined side of the rotating groove. The upper surface of the rotating plate has multiple strip-shaped protrusions.

[0015] By dividing the support plates into fixed plates and rotating plates, when multiple support plates are unfolded and abut against the inner wall of the casting, the rotating plates can adaptively rotate and adjust according to the actual curvature of the inner wall of the casting, so that the ends of the multiple rotating plates can always better fit the inner wall of the casting, improving the stability of the overall support structure. The strip protrusions on the top of the rotating plates can increase the friction between the support plates and the inner wall of the casting, further preventing slippage and displacement during the support process, and ensuring the support effect on the detection shell.

[0016] Preferably, the rubber protective sleeve is spindle-shaped, and the rubber protective sleeve is filled with multiple evenly arranged support steel wires, the direction of which is consistent with the central axis of the rubber protective sleeve.

[0017] In the aforementioned structural design, the rubber protective sleeve, as a key connecting component between the connecting block and the protective shell, plays a crucial bridging role. When the protective shell moves backward due to external force, it compresses the rubber protective sleeve. Once the external force is removed and the protective shell is released, the rubber protective sleeve, thanks to its elastic properties, can accurately push the protective shell back to its initial position. This rubber protective sleeve design not only effectively protects the internal connecting column from external impacts and wear but also cleverly utilizes a spring-like elasticity, reliably ensuring the protective shell automatically returns to its original position after being subjected to force. Furthermore, the rubber protective sleeve employs a unique spindle-shaped design. This structure allows it to expand and deform evenly towards the center under axial pressure, effectively avoiding the shortened compression stroke caused by multiple folds or bends, ensuring sufficient buffering and reset space. Simultaneously, to further enhance the mechanical strength and resilience of the rubber protective sleeve, it is carefully filled with multiple evenly distributed support steel wires. These wires are evenly embedded in the rubber matrix, significantly improving the protective sleeve's support force and durability, maintaining stable performance during repeated compression and rebound.

[0018] The bending or shifting of the protective sleeve will not interfere with the detection angle of the probe, reducing the probability of missing defects due to deformation of the front-end structure during the detection process.

[0019] Preferably, the detection housing includes a detection shell and a protective cover. The visual sensor, LED patch light source and laser projection structure are all disposed inside the detection shell, and the rotatable connection between the detection shell and the connecting column is located on the protective cover. The protective lens on the protective cover is made of saline resin material.

[0020] By detecting the installation method of the detection housing and the specific location of the internal components, the center of gravity of the entire detection housing is shifted to the bottom of the detection housing. As the detection housing is pushed out from the protective housing, the protective cover on the detection housing rotates from a parallel direction to an inclined direction. This allows the vision sensor to better cooperate with the laser projection structure to detect the inner wall of the casting. At the same time, the Sarin resin has excellent impact resistance and light transmittance, which can ensure the normal operation of the detection optical path while providing more reliable protection for the internal detection components and reducing the risk of damage caused by scratches and collisions.

[0021] Preferably, the laser projection structure includes two parallel laser diodes fixedly installed inside the detection housing. The two laser diodes are located on both sides of the vision sensor, and the lasers emitted by the two laser diodes converge at a distance of 5-15 mm from the front end of the protective cover to form a grating.

[0022] Two parallel laser diode mounting holes are opened on the front side wall of the probe to emit linear lasers with a wavelength of 520-650nm. The two laser beams converge at a distance of 5-15mm from the front of the probe to form a grating. By measuring the degree of grating distortion and combining it with the scale of the reticle built into the eyepiece, the depth of the internal flow channel cracks in ultra-high pressure valves and steam turbine castings (accuracy controlled within 0.02mm) and the opening width can be manually read. The laser grating distortion combined with the eyepiece scale reticle allows the operator to directly read the defect depth and width without the need for image processing algorithms. The measurement results are intuitive and reliable, thus meeting the ASME standard's acceptance requirements for defect size.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By using a retractable and movable detection housing in conjunction with a protective housing, the detection housing is retracted inside the protective housing during the process of the optical detection tube extending into the inner cavity of the casting, avoiding direct collision between the lens and the inner wall of the casting. After the optical detection tube moves to the position to be detected, the detection housing is pushed out of the protective housing through the unfolding component, so that the vision sensor is fully exposed and a complete and unobstructed detection angle is obtained, which solves the problem that the existing protection scheme cannot take into account both wear protection and detection angle.

[0024] 2. During the movement of the protective shell, the internally fixed push bar gradually approaches the roller. When the protective shell pushes the detection shell out a little, the push bar abuts against the roller. The trapezoidal push bar will push the roller to rotate, which in turn drives the semi-elliptical detection shell to rotate in the mounting hole. This allows the detection shell to automatically deflect and adjust its angle after extending out of the protective shell, so that the internal vision sensor is aligned with the inner wall of the casting to be inspected. This allows the vision sensor and the laser projection structure to work together better for accurate detection.

[0025] 3. The main steel wire pulls the push ring to one side, causing the push ring to abut against multiple support plates that are set in an inclined state. Since the support plates are arranged at an inclined position at the initial position, the push ring will drive the multiple support plates to gradually unfold during the movement until their ends abut against the inner wall of the casting, forming a stable support structure. This avoids the newly pushed-out end of the detection shell from easily colliding directly with the inner wall of the casting, which would cause friction and damage to the transparent protective cover installed at the end of the detection shell. Attached Figure Description

[0026] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a schematic diagram of the internal structure of the pusher frame in this invention; Figure 3 This is a three-dimensional structural diagram of the protective shell in this invention; Figure 4 This is a schematic diagram of the internal structure of the protective outer shell in this invention; Figure 5 This is a schematic diagram of the main steel wire in this invention; Figure 6 This is a schematic diagram of the rotating plate in this invention; Figure 7 This is a schematic diagram of the internal structure of the rubber protective sleeve in this invention; Figure 8 This is a schematic diagram of the detection shell structure in this invention.

[0027] In the diagram: 1. Detection base; 2. Pusher frame; 3. Support frame; 4. Optical detection tube; 5. Protective housing; 6. Drive handle; 7. 3D electric translation stage; 8. Connecting block; 9. Rubber protective sleeve; 10. Long groove; 11. Support plate; 12. Rubber protective film; 13. Inclined surface; 14. Fixing plate; 15. Rotating plate; 16. Strip protrusion; 17. Connecting column; 18. Push ring; 19. Detection housing; 190. Supporting steel wire; 191. Detection housing; 192. Protective cover; 20. Roller; 21. Main steel wire; 22. Magnet; 23. Vision sensor; 24. LED patch light source; 25. Laser diode; 26. Push bar. Detailed Implementation

[0028] Please see Figures 1 to 8 This invention provides a device for detecting defects in the inner wall of castings with an endoscopic probe, the technical solution of which is as follows: An internal defect detection device for castings with an endoscopic probe includes a detection base 1. A pusher frame 2 is fixedly installed on one side of the detection base 1, and a support frame 3 is fixedly installed on the other side of the detection base 1. A three-dimensional electric translation stage 7 is installed inside the pusher frame 2. An optical detection tube 4 is connected to the three-dimensional electric translation stage 7. The optical detection tube 4 has a multi-jointed serpentine structure inside and a spiral pattern on its outer wall. A drive handle 6 connected to the optical detection tube 4 is installed inside the pusher frame 2. A protective shell 5 is installed at one end of the optical detection tube 4. A detection shell 19 is installed inside the protective shell 5. A vision sensor 23 is installed in the middle of the detection shell 19. Multiple LED patch light sources 24 are arranged in a ring around the vision sensor 23, and laser projection structures are provided on both sides of the vision sensor 23. The laser projection structures include... Two parallel laser diodes 25 are fixedly installed inside the detection housing 191. The two laser diodes 25 are located on both sides of the vision sensor 23. The lasers emitted by the two laser diodes 25 converge at a distance of 5-15 mm from the front end of the protective cover 192 to form a grating. An unfolding assembly is installed inside the protective housing 5. The unfolding assembly is connected to the detection housing 19. When the detection housing 19 moves to a designated position, the unfolding assembly pushes the detection housing 19 out of the protective housing 5. The detection housing 19 includes the detection housing 191 and the protective cover 192. The vision sensor 23, the LED patch light source 24 and the laser projection structure are all located inside the detection housing 191. The rotatable connection between the detection housing 19 and the connecting post 17 is located on the protective cover 192. The protective lens on the protective cover 192 is made of saline resin material.

[0029] The unfolding assembly includes a connecting post 17, one end of which is fixedly installed to the optical detection tube 4, and the other end of which is connected to the detection housing 19. The connecting post 17 and the optical detection tube 4 are connected by a connecting block 8. The protective housing 5 is slidably connected to the connecting post 17. A pushing ring 18 is slidably connected to the connecting post 17. The pushing ring 18 is located inside the protective housing 5. A main steel wire 21 is fixedly installed on the side of the pushing ring 18 away from the detection housing 19. The main steel wire 21 is located inside the optical detection tube 4 and is connected to the drive handle 6. A rubber protective sleeve 9 is fitted on the connecting post 17. The two ends of the rubber protective sleeve 9 are fixedly installed to the connecting block 8 and the protective housing 5, respectively.

[0030] The connecting column 17 has a mounting hole, and the detection housing 19 is rotatably connected to the mounting hole. The detection housing 19 is generally semi-elliptical. A roller 20 is fixedly installed on the rotating shaft of the detection housing 19. A push bar 26 is fixedly installed inside the protective housing 5. When the push bar 26 moves to the designated position, it abuts against the roller 20. The push bar 26 is generally trapezoidal and long, and the entire push bar 26 is made of spring steel.

[0031] The protective shell 5 has multiple evenly arranged elongated grooves 10, and the entire elongated groove 10 has an L-shaped structure. A support plate 11 is provided inside the elongated groove 10. One side of the support plate 11 is rotatably connected to the elongated groove 10, and the other side of the support plate 11 has an arc-shaped cross-section. A rubber protective film 12 is fixedly installed between the support plate 11 and the protective shell 5. When the support plate 11 is in its original position, the support plate 11 is inclined and abuts against a push ring 18 on one side. The side of the push ring 18 away from the detection shell 19 is arc-shaped. A magnet 22 is provided on one side of the elongated groove 10. The magnet 22 is fixedly installed on the connecting column 17 and attracts the support plate 11.

[0032] The supporting plate 11 includes a fixed plate 14 and a rotating plate 15. A rotating groove is provided on one side of the fixed plate 14, and an inclined surface 13 is provided on one side of the rotating groove, with the inclined direction being upward. The rotating plate 15 is rotatably connected in the rotating groove. One side of the rotating plate 15 and the inclined side of the rotating groove cooperate with each other. Multiple strip-shaped protrusions 16 are provided on the upper surface of the rotating plate 15.

[0033] The rubber protective sleeve 9 is spindle-shaped, and the rubber protective sleeve 9 is filled with multiple evenly arranged support steel wires 190. The direction of the support steel wires 190 is consistent with the direction of the central axis of the rubber protective sleeve 9.

[0034] When using the testing equipment: First, fix the casting to be tested on the support frame 3, pre-calibrate the three-dimensional electric translation stage 7 and set the testing path so that the optical detection tube 4 can be aligned with the inner cavity opening of the casting. Then, according to the testing requirements, insert the optical detection tube 4 into the casting and pull the steel wire through the drive handle 6. Since the optical detection tube 4 has a multi-joint serpentine structure, it can bend and adjust adaptively with the direction of the inner wall of the casting. With the adjustment of the overall feed position in conjunction with the three-dimensional electric translation stage 7, the detection housing 19 with the detection element at the end can be sent into the designated detection position on the inner wall of the casting. After reaching the detection position, the drive handle 6 pulls the main steel wire 21.

[0035] The main steel wire 21 pulls the push ring 18 to one side, causing the push ring 18 to abut against multiple inclined support plates 11. Since the support plates 11 are inclined in the initial position, the push ring 18 will drive the multiple support plates 11 to gradually unfold during the movement until their ends abut against the inner wall of the casting, forming a stable support structure. At the same time, as the push ring 18 continues to move forward, the detection shell 19 is smoothly pushed out without deviation or collision. By dividing the support plates 11 into fixed plates 14 and rotating plates 15, when the multiple support plates 11 unfold and abut against the inner wall of the casting, the rotating plates 15 can adaptively rotate and adjust according to the actual curvature of the inner wall of the casting, so that the ends of the multiple rotating plates 15 can always better fit against the inner wall of the casting, improving the stability of the overall support structure. The strip protrusion 16 above the rotating plate 15 can increase the friction between the support plates 11 and the inner wall of the casting, further preventing slippage and deviation during the support process, and ensuring the support effect on the detection shell 19.

[0036] The main steel wire 21 drives the push ring 18 to move along the connecting post 17 towards the detection housing 19. The push ring 18 pushes the protective housing 5 to slide on the connecting post 17, and the rubber protective sleeve 9 stretches out accordingly. During the movement of the protective housing 5, the internally fixed push strip 26 gradually approaches the roller 20. When the protective housing 5 pushes the detection housing 19 out a little, the push strip 26 abuts against the roller 20. The trapezoidal push strip 26 pushes the roller 20 to rotate, which in turn drives the semi-elliptical detection housing 19 to rotate within the mounting hole. This causes the detection housing 19 to extend out of the protective housing 5 and rotate 90° to adjust its angle, so that the internal vision sensor 23 is aligned with the inner wall of the casting to be inspected. Subsequently... The surrounding LED patch light source 24 and the laser projection structures on both sides are activated, emitting linear lasers with a wavelength of 520-650nm. The two laser beams converge at a distance of 5-15mm from the front end of the probe to form a grating. By measuring the degree of grating distortion and combining it with the scale of the reticle built into the eyepiece, the depth of the internal flow channel cracks in ultra-high pressure valves and steam turbine castings (accuracy controlled within 0.02mm) and the opening width are manually read. The laser grating distortion combined with the eyepiece scale reticle allows the operator to directly read the defect depth and width without the need for image processing algorithms. The measurement results are intuitive and reliable, thus meeting the ASME standard's acceptance requirements for defect size and completing the defect detection operation.

[0037] When the protective shell 5 moves backward due to external force, it compresses the rubber protective sleeve 9. Once the external force is removed and the protective shell 5 is released, the rubber protective sleeve 9, with its own elastic properties, can push the protective shell 5 back to its initial position accurately. The design of the rubber protective sleeve 9 not only effectively protects the internal connecting column 17 from external impact and wear, but also cleverly plays a spring-like elastic role, thus reliably causing the protective shell 5 to automatically return to its original position after being subjected to force. In addition, the rubber protective sleeve 9 adopts a unique spindle-shaped design. This structure allows it to expand and deform evenly towards the center when subjected to axial pressure, effectively avoiding the problem of shortened compression stroke caused by multiple folds or bends, ensuring sufficient buffering and reset space. At the same time, in order to further enhance the mechanical strength and resilience of the rubber protective sleeve 9, multiple evenly distributed support steel wires 190 are carefully filled inside. These steel wires are evenly embedded in the rubber matrix, significantly improving the support force and durability of the protective sleeve, enabling it to maintain stable performance during repeated compression and rebound.

[0038] After the test is completed, the main steel wire 21 is de-stressed, the rubber protective sleeve 9 retracts and springs back, driving the protective shell 5 to reset. The test shell 19 is then retracted into the protective shell 5, and the device can be pulled out of the casting, completing the entire test process. A magnet 22 is installed on one side of the long groove 10. The magnet 22 can attract the support plate 11. Combined with the rubber protective film 12 covering the surface of the support plate 11, during the process of the push ring 18 completing the push action and returning to its original position, the support plate 11 can smoothly return to its initial tilt position with the help of the elastic restoring force of the rubber protective film 12. The magnet 22 then attracts and fixes the support plate 11 after it is reset, ensuring that it remains stable in the non-working state, thus preparing for the next test operation.

[0039] The specific embodiment of the present invention has been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the embodiments described above. For those skilled in the art, various changes, modifications, substitutions, and variations made to these embodiments without departing from the principles and ideas of the present invention should still fall within the protection scope of the present invention.

Claims

1. A device for detecting defects in the inner wall of a casting with an endoscopic probe, comprising a detection base (1), a pusher (2) fixedly mounted on one side of the detection base (1), and a support frame (3) fixedly mounted on the other side of the detection base (1), characterized in that, The pusher (2) is equipped with a three-dimensional electric translation stage (7), which is connected to an optical detection tube (4). The optical detection tube (4) has a multi-joint serpentine structure inside and a spiral pattern on the outer wall. The pusher (2) is equipped with a drive handle (6) connected to the optical detection tube (4). One end of the optical detection tube (4) is equipped with a protective shell (5). The protective shell (5) is equipped with a detection shell (19). A vision sensor (23) is installed in the middle of the detection shell (19). Multiple LED patch light sources (24) are arranged in a ring around the vision sensor (23). Laser projection structures are provided on both sides of the vision sensor (23). An unfolding component is installed inside the protective shell (5). The unfolding component is connected to the detection shell (19). When the detection shell (19) moves to a designated position, the unfolding component pushes the detection shell (19) out of the protective shell (5).

2. The device for detecting defects in the inner wall of a casting with an endoscopic probe according to claim 1, characterized in that, The unfolding assembly includes a connecting column (17), one end of which is fixedly installed with an optical detection tube (4), and the other end of which is connected to a detection housing (19). The connecting column (17) and the optical detection tube (4) are connected by a connecting block (8). The protective housing (5) is slidably connected to the connecting column (17). A pushing ring (18) is slidably connected to the connecting column (17). The pushing ring (18) is located inside the protective housing (5). A main steel wire (21) is fixedly installed on the side of the pushing ring (18) away from the detection housing (19). The main steel wire (21) is located inside the optical detection tube (4) and is connected to a drive handle (6). A rubber protective sleeve (9) is fitted on the connecting column (17). The two ends of the rubber protective sleeve (9) are fixedly installed with the connecting block (8) and the protective housing (5) respectively.

3. The device for detecting defects in the inner wall of a casting with an endoscopic probe according to claim 2, characterized in that, The connecting column (17) has an installation hole, and the detection housing (19) is rotatably connected in the installation hole. The detection housing (19) is generally semi-elliptical. A roller (20) is fixedly installed on the rotating shaft of the detection housing (19). A push bar (26) is fixedly installed inside the protective housing (5). When the push bar (26) moves to the designated position, it abuts against the roller (20). The push bar (26) is generally trapezoidal and long. The push bar (26) is made of spring steel.

4. The device for detecting defects in the inner wall of a casting with an endoscopic probe according to claim 2, characterized in that, The protective shell (5) has a plurality of evenly arranged elongated grooves (10). The elongated grooves (10) are generally L-shaped. A support plate (11) is provided in the elongated groove (10). One side of the support plate (11) is rotatably connected to the elongated groove (10). The other side of the support plate (11) has an arc-shaped cross section. A rubber protective film (12) is fixedly installed between the support plate (11) and the protective shell (5). When the support plate (11) is in its original position, the support plate (11) is inclined and abuts against the push ring (18) on one side. The side of the push ring (18) away from the detection shell (19) is arc-shaped. A magnet (22) is provided on one side of the elongated groove (10). The magnet (22) is fixedly installed on the connecting column (17). The magnet (22) attracts the support plate (11).

5. The device for detecting defects in the inner wall of a casting with an endoscopic probe according to claim 4, characterized in that, The supporting plate (11) includes a fixed plate (14) and a rotating plate (15). A rotating groove is provided on one side of the fixed plate (14). An inclined surface (13) is provided on one side of the rotating groove, and the inclined direction is upward. The rotating plate (15) is rotatably connected in the rotating groove. One side of the rotating plate (15) and the inclined side of the rotating groove cooperate with each other. A plurality of strip protrusions (16) are provided on the upper surface of the rotating plate (15).

6. The device for detecting defects in the inner wall of a casting with an endoscopic probe according to claim 2, characterized in that, The rubber protective sleeve (9) is spindle-shaped, and the rubber protective sleeve (9) is filled with multiple evenly arranged support steel wires (190). The direction of the support steel wires (190) is consistent with the direction of the central axis of the rubber protective sleeve (9).

7. The device for detecting defects in the inner wall of a casting with an endoscopic probe according to claim 1, characterized in that, The detection housing (19) includes a detection housing (191) and a protective cover (192). The visual sensor (23), LED patch light source (24) and laser projection structure are all disposed inside the detection housing (191). The rotatable connection between the detection housing (19) and the connecting column (17) is located on the protective cover (192). The protective lens on the protective cover (192) is made of saline resin material.

8. The device for detecting defects in the inner wall of a casting with an endoscopic probe according to claim 7, characterized in that, The laser projection structure includes two parallel laser diodes (25) fixedly installed inside the detection housing (191). The two laser diodes (25) are located on both sides of the vision sensor (23). The lasers emitted by the two laser diodes (25) converge at a distance of 5-15 mm from the front end of the protective cover (192) to form a grating.

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