A robotic arm and method for grasping foreign objects from the bottom end cap of a voltage regulator.

Abstract

This application provides a robotic arm and method for grasping foreign objects from the bottom end cap of a pressurizer, comprising a tensioning assembly, a waist rotation joint assembly, a shoulder swing joint assembly, an elbow rotation joint assembly, a wrist swing joint assembly, a wrist rotation joint assembly, a tool mounting interface assembly, and a foreign object grasping tool, connected in sequence. The tensioning assembly includes an actuating pneumatic circuit element, a pressure-holding pneumatic circuit element, a tensioning mechanism end cap, a base, a tensioning mechanism, and a distance sensor. The robotic arm is limited after contacting the upper end face of the lower support plate of the pressurizer via the flange end face of the base. The tensioning mechanism is tightly fitted to the inner wall of the central hole of the lower support plate via three tensioning blocks evenly distributed around its end circumference. The tool mounting interface assembly includes a quick-change device mounting base, a camera mounting base, a quick-rotation device, and a camera. This application addresses the problem of unreliable recyclability in grasping foreign objects from the bottom end cap of a nuclear power plant pressurizer by incorporating the tensioning assembly.

Description

Technical Field

[0001] This application belongs to the field of nuclear industry robot technology, specifically relating to a robotic arm and method for grasping foreign objects from the bottom end cap of a pressure regulator. Background Technology

[0002] The pressurizer is one of the main pieces of equipment in a nuclear power plant. During reactor startup, shutdown, steady-state power operation, normal power changes, and various accident conditions, it controls and protects the pressure of the reactor coolant system. It also assists in reactor startup, shutdown, and degassing.

[0003] refer to Figure 1 The voltage regulator is a vertical cylindrical high-pressure vessel, consisting of a cylinder, an upper support plate, a lower support plate 110, an electric heating element 120, and a bottom end cap 130. The bottom end cap assembly and the lower support plate form a cavity, and a fluid distribution cover 140 is welded to the center of the bottom of the lower end cap assembly. In recent years, an incident occurred at a domestic nuclear power plant where a valve seat disc spring entered the bottom head 130 of the pressurizer. To remove the foreign object (such as the valve seat disc spring), a method was used: an aluminum-plastic rod was inserted through the manhole, passed through the lower support plate to the bottom head, and then the foreign object was retrieved by adhering to the end of the rod. This method required manually adjusting the position of the end using an adjusting rope exceeding 10 meters, making precise positioning and retrieval of the foreign object impossible. Especially in areas with dense heating pipes on the bottom head, this method could not even reach the vicinity of the foreign object. Furthermore, because it used an adhesive method, it was only suitable for retrieving large, sheet-like foreign objects, meaning only a single object could be retrieved. Also, due to the adhesive method, the foreign object was prone to falling back during recovery, indicating unreliable retrieval capabilities. Currently, there is no intelligent device in China specifically designed for retrieving foreign objects from the bottom head of nuclear power plant pressurizers. Summary of the Invention

[0004] In view of this, the embodiments of this application are committed to providing a robotic arm and method for grasping foreign objects from the bottom end cap of a pressurizer. By adopting a pneumatic tensioning mechanism positioning structure and joint electric drive closed-loop control in the tensioning assembly of the foreign object grasping robotic arm, the problem of unreliable recovery of foreign objects from the bottom end cap of nuclear power plant pressurizers in the prior art can be solved.

[0005] The first aspect of this application provides a robotic arm for grasping foreign objects from the bottom end cap of a voltage regulator. This robotic arm includes, in sequence, a tensioning assembly, a waist rotation joint assembly, a shoulder swing joint assembly, an elbow rotation joint assembly, a wrist swing joint assembly, a wrist rotation joint assembly, a tool mounting interface assembly, and a foreign object grasping tool. The tensioning assembly includes an actuating pneumatic element, a pressure-holding pneumatic element, a tensioning mechanism end cap, a base, a tensioning mechanism, and a distance sensor. The robotic arm is limited after contacting the upper end face of the lower support plate of the voltage regulator via the flange end face of the base in the tensioning assembly. The tensioning mechanism in the tensioning assembly has three tensioning blocks evenly distributed around its end circumference that fit tightly against the inner wall of the central hole of the lower support plate, securing the robotic arm after it is lowered into position. The distance sensor in the tensioning assembly controls the accurate lowering of the robotic arm onto the upper end face of the lower support plate. The tool mounting interface assembly includes a quick-change device mounting base, a camera mounting base, a quick-rotation device, and a camera. The quick-change device mounting base is used to mount the quick-rotation device. The camera mount is used to mount the camera. The foreign object gripper connects to the quick-change mechanism in the quick-change connector assembly.

[0006] In one specific embodiment of this application, the lumbar rotation joint assembly includes an upper connecting seat, a motor mounting cylinder seat, a lower connecting seat, and a joint motor assembly. The elbow rotation joint assembly has the same structural composition as the lumbar rotation joint assembly. The wrist rotation joint assembly has the same structural composition as the lumbar rotation joint assembly.

[0007] In one specific embodiment of this application, the shoulder swing joint assembly includes a joint motor assembly, a motor mounting cylinder, a joint cylinder, a connecting lug, an end cap, a connecting base, an electromagnetic clutch, a transmission gear, and a transmission shaft. The output end of the joint motor assembly in the shoulder swing joint is fixedly connected to the input bevel gear of the transmission gear. The output bevel gear of the transmission gear is connected to the transmission shaft via a key, and the transmission shaft is connected to the connecting lug via a key. The wrist swing joint assembly has the same structural composition as the shoulder swing joint assembly.

[0008] In one specific embodiment of this application, the circumferential fixing screw through hole of the tensioning component is fixedly connected to the circumferential fastening screw thread hole of the waist rotation joint component by a screw; the circumferential fastening screw thread hole of the waist rotation joint component is fixedly connected to the circumferential fastening screw through hole of the shoulder swing joint by a screw; similarly, the circumferential fastening screw thread hole of the shoulder swing joint is fixedly connected to the circumferential fastening screw through hole of the elbow rotation joint component by a screw; the circumferential fastening screw thread hole at the lower end of the elbow rotation joint component is fixedly connected to the circumferential fastening screw through hole at the upper end of the wrist swing joint component by a screw; the circumferential fastening screw thread hole at the lower end of the wrist swing joint component is fixedly connected to the circumferential fixing screw through hole at the upper end of the quick-connect coupling component by a screw.

[0009] In one specific embodiment of this application, the foreign object gripping tool is a pneumatic gripper tool.

[0010] In one specific embodiment of this application, the foreign object grasping tool includes any one or more of a long-handled grasping tool, an adaptive grasping tool, and a V-shaped gripper tool.

[0011] The second aspect of this application provides a method for grasping foreign objects from the bottom end cap of a voltage regulator. The method includes: after a robotic arm is securely installed on the lower support plate of the voltage regulator, the waist rotation joint assembly, shoulder swing joint assembly, elbow rotation joint assembly, wrist swing joint assembly, and wrist rotation joint assembly continue to move in conjunction according to a suitable working path, avoiding the electric heating element in the bottom end cap area, and then moving to the location of the target foreign object; the foreign object is grasped by a dedicated foreign object grasping tool at the end of the device, in conjunction with an end-grabbing monitoring camera.

[0012] The beneficial effects of this application's technical solution are as follows: By employing a pneumatic tensioning mechanism positioning structure and joint electric drive closed-loop control in the tensioning assembly of the foreign object grasping robot, the robot's end effector can accurately reach the position of the foreign object through program control. Therefore, compared to manual long-bar grasping, it can achieve precise positioning and grasping of foreign objects. In addition, the robot's end effector uses a unified quick-change tool, which can be equipped with different grippers to handle various foreign objects of different shapes, such as fragments, rings, and rods. Therefore, compared to the limited range of foreign objects that can be manually grasped with a long bar, the foreign object grasping robot of this application can grasp a variety of foreign objects. Attached Figure Description

[0013] Figure 1 The diagram shows the location of the foreign object inside the voltage regulator.

[0014] Figure 2 The diagram shown is a structural schematic of a robotic arm for grasping foreign objects from the bottom end cap of a voltage regulator, according to an embodiment of this application.

[0015] Figure 3 The diagram shown is a structural schematic of a tightening mechanism in a robotic hand for grasping foreign objects from the bottom end cap of a voltage regulator, according to an embodiment of this application.

[0016] Figure 4 As shown Figure 3 A partial structural schematic diagram of the tightening mechanism in the robotic hand for grasping foreign objects from the bottom end cap of the voltage regulator in the embodiment shown.

[0017] Figure 5 The diagram shown is a structural schematic of the waist-mounted rotary joint assembly of a manipulator for grasping foreign objects from the bottom end cap of a voltage regulator, according to an embodiment of this application.

[0018] Figure 6 The diagram shown is a structural schematic of the shoulder swing joint assembly of a manipulator for grasping foreign objects from the bottom end of a voltage regulator, according to an embodiment of this application.

[0019] Figure 7 As shown Figure 6 A schematic diagram of the assembly of the shoulder swing joint assembly in the manipulator for grasping foreign objects at the bottom end of the voltage regulator in the embodiment shown.

[0020] Figure 8 The diagram shown is a structural schematic of a tool mounting interface assembly for a manipulator used for grasping foreign objects from the bottom end cap of a voltage regulator, according to an embodiment of this application.

[0021] Figure 9 The diagram shown is a partial structural schematic of a foreign object grasping robot for a voltage regulator bottom end cap according to an embodiment of this application.

[0022] Figure 10 The diagram shown is a partial structural schematic of another part of a foreign object grasping robot provided in an embodiment of this application.

[0023] Figure 11 The diagram shown is a structural schematic of a manipulator for grasping foreign objects from the bottom end cap of a voltage regulator, provided in an embodiment of this application, and equipped with different end-effectors for grasping foreign objects.

[0024] Figure 12 The diagram shown is a flowchart illustrating a method for grasping foreign objects from the bottom end cap of a voltage regulator according to an embodiment of this application. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] At least one embodiment of this application provides a robotic arm 200 for grasping foreign objects from the bottom end cap of a voltage regulator, see reference. Figure 2 The manipulator 200 for grasping foreign objects at the bottom end of the voltage regulator includes, in sequence, a tensioning assembly 1, a waist rotation joint assembly 2, a shoulder swing joint assembly 3, an elbow rotation joint assembly 4, a wrist swing joint assembly 5, a wrist rotation joint assembly 6, a tool mounting interface assembly 7, and a foreign object grasping tool 8. (Reference) Figure 3 and Figure 4 The tensioning assembly 1 includes an actuating pneumatic element 1.1, a pressure-holding pneumatic element 1.2, a tensioning mechanism end cap 1.3, a base 1.4, a tensioning mechanism 1.5, and a distance sensor 1.6. The robotic arm is limited after contacting the upper end face of the lower support plate of the pressure regulator via the flange end face of the base 1.4 in the tensioning assembly 1. The tensioning mechanism 1.5 in the tensioning assembly 1 uses three evenly distributed tensioning blocks 1.5a at its end circumference to tightly fit against the inner wall of the central hole 110a of the lower support plate 110, thereby securing the robotic arm after it is lowered into position. The distance sensor 1.6 in the tensioning assembly 1 is used to control the accurate lowering of the robotic arm onto the upper end face of the lower support plate. (Reference) Figure 8 The tool mounting interface assembly 7 includes a quick-change device mounting base 7.1, a camera mounting base 7.2, a quick-rotation device 7.3, and a camera 7.4. The quick-change device mounting base 7.1 is used to mount the quick-rotation device 7.3. The camera mounting base 7.2 is used to mount the camera 7.4. The foreign object gripping tool 8 is connected to the quick-rotation device 7.3 in the quick-change connector assembly 7.

[0027] For example, the installation process of the foreign object grasping robot arm for the bottom end cap of the voltage regulator: The robot arm is lowered through the center hole of the lower support plate of the voltage regulator. The distance sensor 1.6 detects the distance to the bottom end face of the flange of the base 1.4 in real time. After the bottom end face of the flange of the base 1.4 contacts the lower support plate of the voltage regulator, under the action of the appropriate air pressure introduced by the actuating air circuit element 1.1, the three expansion blocks of the pneumatic expansion mechanism in the expansion assembly 1 extend outward synchronously along the radial direction of the expansion mechanism end cover 1.3 until they are pressed against the inner wall of the center hole of the lower support plate. The installation is then completed. The process of the robot arm being fastened to the center hole of the lower support is as follows. Figure 9 .

[0028] According to the technical solution provided in this application, by employing a pneumatic tensioning mechanism positioning structure and joint electric drive closed-loop control in the tensioning assembly of the foreign object grasping robot, the robot's end effector can accurately reach the position of the foreign object through program control. Therefore, compared to the manual long-bar grasping method, precise positioning and grasping of foreign objects can be achieved. In addition, the robot's end effector uses a unified quick-change tool, which can be equipped with different grippers to handle various foreign objects of different shapes, such as fragments, rings, and rods. Therefore, compared to the limited range of foreign objects that can be manually grasped with a long bar, the foreign object grasping robot of this application can grasp a variety of foreign objects.

[0029] In at least one embodiment of this application, reference is made to Figure 5 The lumbar rotation joint assembly 2 includes an upper connecting seat 2.1, a motor mounting cylinder seat 2.2, a lower connecting seat 2.3, and a joint motor assembly 2.4. The elbow rotation joint assembly 4 has the same structural composition as the lumbar rotation joint assembly 2. The wrist rotation joint assembly 6 has the same structural composition as the lumbar rotation joint assembly 2.

[0030] In at least one embodiment of this application, reference is made to Figure 6 and Figure 7 The shoulder swing joint assembly 3 includes a joint motor assembly 3.1, a motor mounting cylinder seat 3.2, a joint cylinder 3.3, a connecting ear 3.4, an end cap 3.5, a connecting base 3.6, an electromagnetic clutch 3.7, a transmission gear 3.8, and a transmission shaft 3.9. The output end of the joint motor assembly 3.1 in the shoulder swing joint 3 is fixedly connected to the input bevel gear of the transmission gear 3.8. The output bevel gear of the transmission gear 3.8 is connected to the transmission shaft 3.9 via a key, and the transmission shaft 3.9 is connected to the connecting ear 3.4 via a key. The wrist swing joint assembly 5 has the same structural composition as the shoulder swing joint assembly 3. Thus, the shoulder joint of the foreign object grasping robot of this application adopts an electromagnetic clutch structure. In the event of an unexpected malfunction and shutdown of the robot arm's joint motor, the electromagnetic clutch can be released via an external air source, causing the shoulder joint to be in a free-hanging state. This enables abnormal retrieval of the robot arm, ultimately ensuring the reliability of foreign object retrieval.

[0031] In at least one embodiment of this application, the circumferential fixing screw through hole A of the tensioning component 1 is fixedly connected to the circumferential fastening screw thread hole A of the waist rotation joint component 2 by screws; the circumferential fastening screw thread hole B of the waist rotation joint component 2 is fixedly connected to the circumferential fastening screw through hole B of the shoulder swing joint 3 by screws; similarly, the circumferential fastening screw thread hole C of the shoulder swing joint 3 is fixedly connected to the circumferential fastening screw through hole of the elbow rotation joint component 4 by screws; the circumferential fastening screw thread hole at the lower end of the elbow rotation joint component 4 is fixedly connected to the circumferential fastening screw through hole at the upper end of the wrist swing joint component 5 by screws; the circumferential fastening screw thread hole at the lower end of the wrist swing joint component 5 is fixedly connected to the circumferential fastening screw through hole at the upper end of the wrist rotation joint component 6 by screws; the circumferential fastening screw thread hole at the lower end of the wrist rotation joint component 6 is fixedly connected to the circumferential fixing screw through hole at the upper end of the quick-connect connector component 7 by screws. Thus, the connection points of adjacent sub-components of the robotic arm are tightened by circumferential screws.

[0032] In at least one embodiment of this application, the foreign object gripping tool 8 is a pneumatic gripper tool. Thus, by supplying a larger air pressure to the foreign object gripping tool 8 through an external device, the gripping force remains stably high after the foreign object is gripped. Therefore, compared to the smaller gripping force of a manual long rod, the foreign object gripping robot of this application grips foreign objects more securely.

[0033] In at least one embodiment of this application, reference is made to Figure 11 The foreign object grasping tool 8 includes one or more of the following: a long-handled grasping tool 8a, an adaptive grasping tool 8b, and a V-shaped gripper tool 8c. The long-handled grasping tool is used to grasp foreign objects at the far end of the bottom end cap area, the adaptive grasping tool is used to grasp foreign objects with a relatively large area (such as fragments or rings), and the V-shaped gripper tool is used to grasp rod-shaped foreign objects. Thus, the end effector of this robotic arm can be equipped with corresponding grasping tools to grasp foreign objects of different shapes, sizes, and positions, achieving the grasping of foreign objects of various shapes.

[0034] At least one embodiment of this application also provides a method for grasping foreign objects from the bottom end cap of a voltage regulator, see reference. Figure 12 The method for grasping foreign objects from the bottom end cap of this voltage regulator includes the following steps. The process and principle of this method for grasping foreign objects from the bottom end cap are described below. Figure 10 .

[0035] S1: After the robotic arm is securely installed on the lower support plate of the voltage stabilizer, the waist rotation joint assembly, shoulder swing joint assembly, elbow rotation joint assembly, wrist swing joint assembly and wrist rotation joint assembly continue to work together according to the appropriate working path, and move to the location of the target foreign object after avoiding the electric heating element in the bottom end cap area.

[0036] S2: Foreign objects can be captured using a dedicated foreign object capture tool at the end of the device, in conjunction with a camera for end-of-device capture monitoring.

[0037] It should be noted that the method for grasping foreign objects from the bottom end cap of the voltage regulator uses a robotic arm for grasping foreign objects from the bottom end cap of the voltage regulator provided in the embodiments of this application. It has the corresponding technical features in the above embodiments and can achieve the corresponding technical effects, which will not be elaborated here.

[0038] It should also be noted that the combination of the technical features in the embodiments of this application is not limited to the combination methods described in the embodiments of this application or the combination methods described in specific embodiments. All technical features described in this application can be freely combined or combined in any way, unless there is a contradiction between them.

[0039] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" are not specifically singular and may include plural forms. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0040] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications or equivalent substitutions made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A robotic arm for grasping foreign objects from the bottom end cap of a voltage regulator, characterized in that, It includes, in sequence, a tensioning assembly, a waist rotation joint assembly, a shoulder swing joint assembly, an elbow rotation joint assembly, a wrist swing joint assembly, a wrist rotation joint assembly, a work tool mounting interface assembly, and a foreign object grasping tool. The expansion assembly includes an actuating air circuit element, a pressure-holding air circuit element, an expansion mechanism end cap, a base, an expansion mechanism, and a distance sensor. The robotic arm is limited after contacting the upper end face of the lower support plate of the voltage regulator through the flange end face of the base in the expansion assembly. The tensioning mechanism in the tensioning assembly uses three tensioning blocks evenly distributed around the end circumference to fit tightly against the inner wall of the central hole in the lower support plate, thereby securing the robot arm after it has been lowered into place. The distance sensor in the tensioning assembly is used to control the robot arm to accurately lower onto the upper surface of the lower support plate; The tool mounting interface assembly includes a quick-change device mounting base, a camera mounting base, a quick-rotation device, and a camera. The quick-change device mounting base is used to mount the quick-rotation device, the camera mounting base is used to mount the camera, and the foreign object gripping tool connects to the quick-rotation device in the quick-change connector assembly. Foreign object grasping tools include any one or more of the following: long-hand grasping tools, adaptive grasping tools, and V-shaped gripper tools.

2. The robotic arm for grasping foreign objects from the bottom end cap of a voltage regulator according to claim 1, characterized in that, The lumbar rotation joint assembly includes an upper connecting seat, a motor mounting cylinder seat, a lower connecting seat, and a joint motor assembly. The elbow rotation joint assembly has the same structural composition as the lumbar rotation joint assembly, and the wrist rotation joint assembly has the same structural composition as the lumbar rotation joint assembly.

3. The robotic arm for grasping foreign objects from the bottom end cap of a voltage regulator according to claim 1, characterized in that, The shoulder swing joint assembly includes a joint motor assembly, a motor mounting cylinder, a joint cylinder, a connecting lug, an end cap, a connecting base, an electromagnetic clutch, a transmission gear, and a transmission shaft. The output end of the joint motor assembly in the shoulder swing joint is fixedly connected to the input bevel gear of the transmission gear. The output bevel gear of the transmission gear is connected to the transmission shaft via a key. The transmission shaft is connected to the connecting lug via a key. The structure of the wrist swing joint assembly is the same as that of the shoulder swing joint assembly.

4. The robotic arm for grasping foreign objects from the bottom end cap of a voltage regulator according to claim 1, characterized in that, The circumferential fixing screw through hole of the expansion assembly and the circumferential fastening screw thread hole of the waist rotation joint assembly are fastened together by screws; The threaded hole of the circumferential fastening screw of the lumbar rotation joint assembly is fastened to the through hole of the circumferential fastening screw of the shoulder swing joint by screws. The circumferential fastening screw thread hole of the shoulder swing joint and the circumferential fastening screw through hole of the elbow rotation joint assembly are fastened together by screws. The circumferential fastening screw threaded hole at the lower end of the elbow rotation joint assembly is fastened to the circumferential fastening screw through hole at the upper end of the wrist swing joint assembly by a screw. The circumferential fastening screw thread hole at the lower end of the wrist swing joint assembly is fixed to the circumferential fastening screw through hole at the upper end of the wrist rotation joint assembly by a screw. The circumferential fastening screw threaded hole at the lower end of the wrist rotation joint assembly is fixed to the circumferential fixing screw through hole at the upper end of the quick-change connector assembly by a screw.

5. The robotic arm for grasping foreign objects from the bottom end cap of a voltage regulator according to any one of claims 1 to 4, characterized in that, The foreign object gripper is a pneumatic gripper tool.

6. A method for grasping foreign objects from the bottom end cap of a voltage regulator, characterized in that, A robotic arm for grasping foreign objects from the bottom end cap of a voltage regulator as described in any one of claims 1-5, comprising: After the robotic arm is securely mounted on the lower support plate of the voltage stabilizer, the waist rotation joint assembly, shoulder swing joint assembly, elbow rotation joint assembly, wrist swing joint assembly and wrist rotation joint assembly continue to work together according to the appropriate working path, and move to the location of the target foreign object after avoiding the electric heating element in the bottom end cap area. Foreign objects can be captured by using a dedicated foreign object grasping tool at the end of the device, in conjunction with a camera for end-of-device capture monitoring.

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