Mechanical arm and method for dismounting and mounting a sealing baffle of a steam generator of a nuclear power plant

Abstract

This invention discloses a robotic arm and method for disassembling and assembling sealing plates in nuclear power plant steam generators. The robotic arm's joint segments are connected at both ends to a connecting seat and a working device, respectively. The connecting seat is connected to a first conveying structure. The joint segments include seven degrees of freedom, with the third joint serving as the heavy-duty central pivot. It has both folded and unfolded states. When folded, the radial envelope dimension is smaller than the maximum passage size of the work inlet. When unfolded, the reachable range of the end-effector covers the installation position of the sealing plate. The end-effector adopts a coaxial integrated design of central pneumatic clamping and circumferential air source channel, simultaneously completing the air path sealing connection when gripping the sealing plate. This invention possesses ample degrees of freedom and flexible attitude adjustment capabilities, enabling fully automated disassembly and assembly of sealing plates in confined, high-radiation spaces. It combines high passability, heavy-duty capacity, and adaptability to the nuclear power environment, significantly reducing personnel radiation exposure and improving operational efficiency and reliability.

Description

Technical Field

[0001] This invention relates to the field of nuclear power plant steam generator maintenance technology, and in particular to a robotic arm and method for disassembling and assembling sealing plates of nuclear power plant steam generators. Background Technology

[0002] When inspecting relevant components inside the primary water chamber of the steam generator during a nuclear power plant shutdown and refueling overhaul, it is necessary to install sealing plates to seal the inlet and outlet of the primary coolant and the drain holes of the steam generator to prevent water from the reactor primary circuit pipeline from flowing into the steam generator water chamber.

[0003] Currently, the installation and removal of sealing plates in domestic nuclear power plants are mostly done manually. Due to factors such as high radiation dose inside the steam generator water chamber, narrow space, and complex operation process, there are problems such as excessive radiation dose to personnel, harsh working environment, poor consistency of manual operation, and easy occurrence of problems such as sealing failure and uneven bolt tightening torque, which can cause radioactive water leakage, affect the overhaul schedule and power plant safety. Therefore, it is necessary to conduct research on intelligent installation and removal technology of steam generator primary loop sealing plates and develop complete sets of equipment to replace manual operation, reduce personnel radiation dose, and improve the safety and reliability of operation. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a robotic arm and method for disassembling and assembling sealing plates of steam generators in nuclear power plants.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to construct a robotic arm for disassembling and assembling a sealing plate of a steam generator in a nuclear power plant, including a connecting seat, a joint section, and an end working device for detachably connecting with the sealing plate and simultaneously conveying a power source. The two ends of the joint section are respectively connected to the connecting seat and the end working device, and the connecting seat is used to connect with a first conveying structure. The joint segment includes multiple degrees of freedom and has a folded state and an unfolded state. In the folded state, the rear arm segment of the joint segment is folded together with the forearm segment, so that the forearm segment and the rear arm segment overlap. The radial envelope size of the entire robotic arm is reduced to less than the maximum passage size of the work entrance. In the unfolded state, the reachable range of the end effector covers all installation positions of the sealing plate.

[0006] Furthermore, the joint segment includes at least seven degrees of freedom, and the joint segment includes a first joint, a second joint, a third joint, a fourth joint, a fifth joint, a sixth joint, and a seventh joint connected in sequence; The first joint is a forward joint that rotates about a first axis to rotate forward relative to the connecting seat; the second joint is a lateral joint that rotates about a second axis to rotate laterally relative to the connecting seat; the third joint is a pitch joint that rotates about a third axis to drive the overall pitch rotation of the fourth, fifth, sixth, and seventh joints; the first axis and the second axis are spatially perpendicular to each other and spatially parallel to each other with the third axis. The fourth joint, the fifth joint, the sixth joint, and the seventh joint are sequentially connected between the third joint and the end effector, and are used to adjust the end effector posture of the end effector relative to the third joint.

[0007] Furthermore, in the unfolded state, the entirety of the first joint and the second joint are disposed on opposite sides of the third joint, along with the entirety of the fourth joint, the fifth joint, the sixth joint, and the seventh joint; In the folded state, the entirety of the first joint and the second joint, along with the entirety of the fourth joint, the fifth joint, the sixth joint, and the seventh joint, are located on one side of the third joint and overlap.

[0008] Furthermore, the third joint is a heavy-duty joint, which adopts a worm gear transmission structure to bear the gravity load of the fourth to seventh joints, the end working device, and the sealing plate. Furthermore, the third joint includes a mounting shell, a third motor, a worm gear, a worm wheel, a rotating shaft, and a tilting shaft. The third motor, the worm gear, and the worm wheel are all located inside the mounting shell. The output shaft of the third motor is connected to the worm gear, the worm gear is meshed with the worm wheel, the rotating shaft is fixedly connected to the worm wheel, and both ends of the rotating shaft extend out of the mounting shell and are respectively connected to the tilting shaft. The third motor drives the worm gear to rotate, which in turn drives the worm wheel to rotate, synchronously transmitting power to the rotating shaft and the flipping shaft. The other end of the flipping shaft is connected to the fourth joint, thereby driving the fourth to the seventh joint to flip as a whole, finally achieving the folded or unfolded state of the joint segment.

[0009] Furthermore, the single-stage transmission ratio of the worm gear transmission structure of the third joint is 20~40, the module is 4~8, and the external dimensions of the worm gear transmission structure are set such that the cross-sectional dimension envelope of the joint segment is smaller than the through dimension of the working inlet.

[0010] Furthermore, the end-effector includes a mounting base, a pneumatic clamping device, and an air source input channel. The pneumatic clamping device protrudes and is fixed to the mounting base for quick connection of the sealing plate. The air source input channel is located on the mounting base and on the outer periphery of the pneumatic clamping device for supplying air to the sealing plate.

[0011] Furthermore, the air source input channel includes a main air intake path connected to an external air source and multiple branch air paths connected to the main air intake path. The multiple branch air paths are arranged at intervals along the circumference of the pneumatic clamping device. The outlet end of each branch air path is respectively used to connect to multiple screwing units on the sealing plate, so as to provide a power air source for each screwing unit when the end working device grips the sealing plate.

[0012] Furthermore, the pneumatic clamping device includes a housing, a piston, an elastic reset member, and a plurality of balls; the housing has an axially extending piston cavity, and the side wall of the housing has a plurality of ball holes communicating with the piston cavity, the plurality of ball holes being arranged at intervals along the circumference of the housing; the piston is slidably disposed in the piston cavity, one end of the piston having a tapered pushing surface, the elastic reset member being disposed in the piston cavity and abutting between the piston and the housing; each ball hole contains one ball, the diameter of the ball being larger than the diameter of the ball hole; The housing is provided with an air inlet communicating with the piston chamber, and the air inlet is used to connect to an air source; when air is supplied, compressed air pushes the piston to move axially, and the conical pushing surface pushes each of the ball parts out of the ball hole to realize the radial expansion of the pneumatic clamping device; when pressure is released, the elastic reset member drives the piston to reset, and all the balls retract into the ball hole to realize the radial contraction of the pneumatic clamping device.

[0013] Furthermore, the end-effector also includes a visual positioning device, which is at least fixed to the mounting base and is used to collect image information of the sealing plate and the installation station to provide feedback and guidance on the position of the end-effector.

[0014] The present invention also provides a method for disassembling and assembling sealing plates for nuclear power plant steam generators, using the robotic arm described in any of the above-mentioned embodiments for disassembling and assembling sealing plates for nuclear power plant steam generators. The method includes the following installation steps: S1: Adjust the joints of the robotic arm to a folded state, so that the radial envelope dimension of the robotic arm is reduced to less than the passage dimension of the work entrance, and then use the first conveying structure to send the robotic arm into the work space through the work entrance; S2: Use the second conveying mechanism to send the sealing plate into the working space through the working inlet; S3: After the robotic arm enters the work space, each joint of the joint segment moves the end-effector to the position of the sealing plate, thereby locking the adapter of the end-effector to the sealing plate, and providing working power while grasping. S4: The end working device carrying the sealing plate is transported to the target installation position through the joint segment. After the sealing plate is precisely aligned with the pipe seat, the screwing unit on the sealing plate is driven by the air source to tighten the fastening bolts, thus completing the locking and installation of the sealing plate.

[0015] Furthermore, in step S1, adjusting the joint segments of the robotic arm to a folded state specifically includes: Adjust the fourth, fifth, sixth, and seventh joints and the end effector to a horizontal position, drive the third joint to rotate so that the joint segment as a whole is in a folded position, and make the cross-sectional dimension envelope of the joint segment smaller than the through dimension of the working inlet; The robotic arm is conveyed into the work space through the first conveying structure. When the fourth joint enters the work entrance as a whole, the first, third and fourth joints are driven to rotate in coordination, so that each arm segment of the joint segment gradually arches up to reduce the overall length of the joint segment until the end working device has completely passed through the work entrance.

[0016] Furthermore, the following disassembly steps are also included: S5: The joint section sends the end-effector into the working space through the working inlet, and guides it through the visual positioning device to lock and connect the end-effector with the adapter of the sealing plate, while providing working power; S6: The air source drives the screwing unit of the sealing plate to loosen the fasteners of the sealing plate in the opposite direction, so as to separate the sealing plate from the pipe seat, and the end working device carries the sealing plate away from the pipe seat. S7: The end-effector reaches the target position near the work entrance through a preset movement path, places the sealing plate on the plate tray, and the second conveying mechanism transports the plate on the plate tray and the sealing plate out of the work entrance; S8: Adjust the joint segment to a folded state, so that the radial envelope dimension of the robotic arm is reduced to less than the maximum passage dimension of the work entrance, and the first conveying structure removes the joint segment from the work space through the work entrance.

[0017] By implementing this invention, the following beneficial effects are achieved: This invention relates to a robotic arm for the installation and removal of sealing plates in nuclear power plant steam generators. The robotic arm comprises multiple degrees of freedom and has folded and extended states. In its folded state, the robotic arm can enter the work space through a narrow inlet with a limited diameter, allowing for a compact movement. In its extended state, the reach of the end effector covers the installation position of the sealing plate. The ample degrees of freedom allow the robotic arm to flexibly adjust its posture after entering the work space, precisely reaching the target location and meeting the needs of large-scale operations. Simultaneously, the end effector, in conjunction with the sealing plate, automates the entire installation process, reducing the radiation dose to operators in the radiation environment.

[0018] This invention provides a method for the disassembly and assembly of sealing plugs in nuclear power plant steam generators. Based on the robotic arm structure, it further defines the specific operation process for the installation of sealing plugs, enabling operators to operate the robotic arm in a clear step sequence to complete the remote automated installation of the sealing plugs. This improves work efficiency and reliability, and reduces the radiation dose to operators in the radiation environment. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a schematic diagram of the structure of a robotic arm used for disassembling and assembling sealing plates of a nuclear power plant steam generator according to Embodiment 1 of the present invention, wherein it is in the unfolded state; Figure 2 yes Figure 1 A schematic diagram of the robotic arm in its folded state; Figure 3 yes Figure 1 Envelope diagram of the working trajectory of the robotic arm in the image; Figure 4 yes Figure 1 A schematic diagram of the rotation direction of each joint in the joint segment; Figure 5 yes Figure 1 A schematic diagram of the structure of the third joint; Figure 6 yes Figure 1 One of the structural schematic diagrams of the end effector in the diagram; Figure 7 yes Figure 1 The second schematic diagram of the end-effector in the diagram; Figure 8 This is a schematic diagram of the structure of the sealing plate used in Embodiment 1 of the present invention; Figure 9 yes Figure 8 Schematic diagram of the middle blocker adapter; Figure 10This is a diagram illustrating step S1 of the method for disassembling and assembling a sealing plug plate in a nuclear power plant according to Embodiment 2 of the present invention. Figure 11 This is a diagram illustrating the operation method of step S3 in the method for disassembling and assembling sealing plugs for steam generators in nuclear power plants, according to Embodiment 2 of the present invention. Figure 12 This is a diagram illustrating step S4 of the method for disassembling and assembling a sealing plug plate for a nuclear power plant steam generator according to Embodiment 2 of the present invention. Detailed Implementation

[0020] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0021] In the description of the invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of the invention, unless otherwise stated, "a plurality of" means two or more.

[0022] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or a chemical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] Example 1: See Figures 1 to 9 One embodiment of the present invention discloses a robotic arm for disassembling and assembling sealing plates of steam generators in nuclear power plants. It can be applied to remote automated sealing operations of various pipe seats of different specifications in nuclear power plants. It is especially suitable for remote automated sealing operations of pipe seats or condensate pipe seats of primary coolant in a nuclear power plant with narrow inlets, such as during a nuclear power plant shutdown and refueling overhaul. In this case, the narrow inlet refers to a manhole.

[0024] like Figure 1 As shown, the robotic arm includes a connecting base 1, a joint segment 2, and an end effector 3 integrating gripping and power supply functions. The two ends of the joint segment 2 are connected to the connecting base 1 and the end effector 3, respectively. The connecting base 1 is connected to the first conveying structure. The connecting base 1 serves as the overall mounting foundation for the joint segment 2 and the end effector 3. The joint segment 2 is used to adjust the specific position of the end effector 3. The end effector 3 is used to grip the sealing plate 50 and provide power to the sealing plate 50, for example, providing turning power to the turning unit 52 of the sealing plate 50. The first conveying structure provides power and conveying support for the robotic arm. It can employ linear conveying methods such as screw drive, rack and pinion drive, or synchronous belt drive, which are conventional techniques in the field and will not be elaborated upon here.

[0025] See you together Figure 2 Joint segment 2 includes multiple degrees of freedom and has folded and unfolded states. In the folded state, the rear arm segment of joint segment 2 is folded together with the forearm segment, causing the forearm segment and rear arm segment to overlap, and the overall radial envelope dimension of the robotic arm is reduced to less than the maximum passage dimension of the work inlet 20. Here, the rear arm segment refers to all joints that are close to the end effector 3 relative to the folding pivot (as described below as the third joint 23), and the forearm and rear arm segments refer to all joints that are far from the end effector 3 relative to the folding pivot. The radial envelope dimension refers to the maximum projected dimension of the robotic arm on a plane perpendicular to its length direction. By adjusting each joint to a specific folding posture, the overall cross-sectional dimension envelope of the robotic arm is controlled within the passage dimension range of the work inlet 20, ensuring that the robotic arm can smoothly pass through the narrow circular manhole of the steam generator or other shaped work inlets 20. In the unfolded state, each joint of joint segment 2 is unfolded to the working posture, and the reachable range of the end effector 3 covers the installation position 30 of the sealing plate 50, meeting the operational requirements within the work space 10.

[0026] Furthermore, in some embodiments, joint segment 2 includes at least seven degrees of freedom. Joint segment 2 includes a first joint 21, a second joint 22, a third joint 23, a fourth joint 24, a fifth joint 25, a sixth joint 26, and a seventh joint 27 connected in sequence.

[0027] The first joint 21 is a forward joint that rotates about a first axis, rotating forward relative to the connecting seat 1. That is, the first joint 21 drives the entire joint segment 2 to rotate forward relative to the connecting seat 1. The second joint 22 is a lateral joint that rotates about a second axis, rotating laterally relative to the connecting seat 1. That is, the second joint 22 drives the overall lateral rotation of the third joint 23 to the seventh joint 27, providing rotational motion when the robotic arm is deployed, enabling the end effector 3 to cover a larger working range. The third joint 23 is a pitch joint that rotates about a third axis, driving the overall pitch rotation of the fourth joint 24, the fifth joint 25, the sixth joint 26, and the seventh joint 27. The first axis is spatially perpendicular to the second axis and spatially parallel to the third axis.

[0028] The fourth joint 24, the fifth joint 25, the sixth joint 26 and the seventh joint 27 are connected sequentially between the third joint 23 and the end effector 3, and are used to adjust the end attitude of the end effector 3 relative to the third joint 23, so as to realize the precise positioning and attitude adjustment of the end effector 3 in space.

[0029] like Figure 1 As shown, in the unfolded state, the entire first joint 21 and the entire second joint 22 are located on opposite sides of the third joint 23, along with the entire fourth joint 24, the fifth joint 25, the sixth joint 26 and the seventh joint 27.

[0030] like Figure 2 As shown, in the folded state, the entirety of the first joint 21 and the second joint 22, along with the entirety of the fourth joint 24, the fifth joint 25, the sixth joint 26, and the seventh joint 27, are located on one side of the third joint 23 and overlap.

[0031] Joint segment 2 includes seven degrees of freedom, including at least one forward joint, one lateral joint, and one pitch joint, providing three-dimensional spatial adjustment capabilities. Through the configuration of these seven degrees of freedom and three-axis joints, the robotic arm possesses ample motion freedom and flexible attitude adjustment capabilities in three-dimensional space, enabling it to adapt to the complex spatial environment inside the primary water chamber of a nuclear power plant steam generator. The obstacle avoidance capability in confined spaces and full-range operational accessibility provided by the seven-degree-of-freedom redundant drive robotic arm of this invention are not covered by existing technologies.

[0032] To better understand how joint segment 2 works, Figure 4 Based on the central direction and spatial coordinate system, the rotation directions of each joint in joint segment 2 are shown. The first joint 21 rotates around the first axis, the second joint 22 rotates around the second axis, and the third joint 23 rotates around the third axis. Let the first axis shown in the figure be the X-direction, then the third axis is also the X-direction, the second axis is the Z-direction, the fifth joint 25 rotates around the Y-direction, then the fourth joint 24 and the seventh joint 27 both rotate around the X-direction, and the sixth joint 26 both rotates around the Z-direction.

[0033] Understandably, in this embodiment, the third joint 23 is used as the pivot joint during folding, that is, the folding and retraction of joint segment 2 is achieved by the rotation of the third joint 23. However, the present invention is not limited to this. In other embodiments, depending on the size of the work inlet and the specific layout of the work space, the main rotational movement during the folding process can also be undertaken by the fourth joint 24, the fifth joint 25, or other joints of joint segment 2.

[0034] Furthermore, let's see together. Figure 5 In some embodiments, the third joint 23 is a heavy-duty joint, i.e., the joint with the greatest load-bearing capacity of the robotic arm. The third joint 23 employs a worm gear transmission structure to bear the gravitational loads of the fourth joint 24 to the seventh joint 27, the end effector 3, and the sealing plate 50. The worm gear transmission structure has the advantages of a large single-stage transmission ratio and a compact structure. Compared to a single-stage gear transmission, the worm gear can provide a larger transmission ratio within a smaller overall size, meeting the dual requirements of load-bearing capacity and size for heavy-duty joints. Other joints (the first joint 21, the second joint 22, and the fourth joint 24 to the seventh joint 27) can be selected from gear transmission, worm gear transmission, or direct motor drive according to actual needs; this invention does not impose any limitations. Generally, both gear transmission and worm gear transmission are equipped with a drive motor, and the installation position can be adaptively set according to the rotation direction.

[0035] For ease of understanding, the following is one implementation of the third joint 23, such as... Figure 4 and Figure 5 As shown, the third joint 23 includes a mounting shell 231, a third motor 232, a worm gear 233, a worm wheel 234, a rotating shaft 235, and a flipping shaft 236. The third motor 232, worm gear 233, and worm wheel 234 are all located inside the mounting shell 231. The output shaft of the third motor 232 is connected to the worm gear 233, and the worm gear 233 is meshed with the worm wheel 234. The rotating shaft 235 is fixedly connected to the worm wheel 234, and both ends of the rotating shaft 235 extend outside the mounting shell 231 and are connected to the flipping shaft 236 respectively. Its working process is as follows: the third motor 232 drives the worm gear 233 to rotate, and the worm gear 233 drives the worm wheel 234 to rotate, synchronously transmitting the power to the rotating shaft 235 and the flipping shaft 236. The other end of the flipping shaft 236 is connected to the fourth joint 24, thereby driving the fourth joint 24 to the seventh joint 27 to flip as a whole, finally realizing the folded or unfolded state of joint segment 2.

[0036] The following is one implementation of the other joints (joint 21, joint 22, and joints 24 to 27): The first joint 21 includes a first motor and a first support bearing. The output shaft of the first motor is connected to the left side of the connecting seat 1. The right side of the same end of the connecting seat 1 is connected to the seat of the first motor through the first support bearing. The second joint 22 is fixedly connected to the seat of the first motor. When the first motor is started, the seat of the first motor can rotate relative to the connecting seat 1, which in turn drives the second joint 22 to rotate relative to the connecting seat 1.

[0037] The second joint 22 includes a second motor and a second housing. The second motor is disposed inside the second housing, and its output shaft is fixedly connected to the mounting housing 231 of the third joint 23. When the second motor is started, its output shaft drives the third joint 23 to rotate relative to the second joint 22. It is understood that a reduction mechanism or transmission structure can be provided between the output shaft of the second motor and the mounting housing 231 of the third joint 23 as needed.

[0038] The fourth joint 24 includes a fourth motor and a fourth support bearing. The output end of the fourth motor is connected to one side of the tilting shaft 236 of the third joint 23. The other side of the same end of the tilting shaft 236 is rotatably connected to the base of the fourth motor via the fourth support bearing. The fifth joint 25 is fixedly connected to the base of the fourth motor. When the fourth motor is started, the base of the fourth motor can rotate relative to the third joint 23, thereby driving the fifth joint 25 to rotate relative to the third joint 23. It is understood that a reduction mechanism or transmission structure can be installed between the output shaft of the fourth motor and the tilting shaft 236 of the third joint 23 as needed.

[0039] The fifth joint 25 includes a fifth motor and a rotating shaft. The output shaft of the fifth motor is connected to one end of the rotating shaft, and the other end of the rotating shaft is connected to the sixth joint 26. The base of the fifth motor is fixedly connected to the base of the fourth motor in the fourth joint 24. Starting the fifth motor drives the rotating shaft to rotate relative to the fourth joint 24, which in turn drives the sixth joint 26 to rotate. It is understandable that a speed reduction mechanism or transmission structure can be installed between the output shaft of the fifth motor and the rotating shaft, or between the rotating shaft and the sixth joint 26, as needed.

[0040] The sixth joint 26 includes a sixth motor, the base of which is fixedly connected to the rotating shaft of the fifth joint 25, and the output shaft of the sixth motor is connected to the seventh joint 27. Activating the sixth motor drives the seventh joint 27 to rotate relative to its base. It is understood that a reduction gear or transmission structure can be installed between the output shaft of the sixth motor and the seventh joint 27 as needed.

[0041] The seventh joint 27 includes a seventh motor, whose motor mount is fixedly connected to the output shaft of the sixth motor. The output shaft of the seventh motor is connected to the end-effector 3. Activating the seventh motor drives the end-effector 3 to rotate relative to its mount. It is understood that a speed reduction mechanism or transmission structure can be installed between the output shaft of the seventh motor and the end-effector 3 as needed.

[0042] Each joint is designed to achieve rotation in a specific direction. For information on the orientation of each motor, please refer to [reference needed]. Figure 4 The above content will not be repeated here.

[0043] Furthermore, in some embodiments, the single-stage transmission ratio of the worm gear transmission structure of the third joint 23 is 20~40, and the module is 4~8. Extensive experimental verification by the inventors has shown that when the transmission ratio is below 20, the speed reduction and torque increase effect of the worm gear is insufficient, making it difficult to meet the driving requirements of a 40kg load at the end; when the transmission ratio is above 40, the external dimensions of the worm gear increase significantly, causing the cross-sectional dimensions of joint segment 2 to exceed tolerances, failing to meet the size constraints for passing through the Φ406mm manhole. When the module is below 4, the tooth root strength is insufficient, unable to withstand bending and contact stresses under heavy load conditions; when the module is above 8, the external dimensions of the worm gear are too large, also failing to meet the size constraints for passing through the manhole. Therefore, the coordinated selection of a transmission ratio of 20~40 and a module of 4~8 is a key technical means to balance load-bearing capacity and compact size. The external dimensions of the worm gear transmission structure are set such that the cross-sectional dimension envelope of joint segment 2 is smaller than the passage size of the work entrance 20, ensuring that the robotic arm can smoothly pass through the manhole in the folded state. In this embodiment, preferably, the single-stage transmission ratio of the worm gear transmission structure of the third joint 23 is 27, and the module is 6.3.

[0044] Existing technologies often employ harmonic reducer transmission, hydraulic drive, or rope traction, none of which can achieve an effective load of ≥40kg at the end in a confined space. This invention solves the core pain point of disassembling and assembling high-load blockage plates at high water levels through the third joint 23.

[0045] Further, see Figure 1In some embodiments, at least one of the fourth to seventh joints 27 is made of titanium alloy, aluminum alloy, or carbon fiber composite material. Since the fourth to seventh joints 27 are located at the end of the robotic arm, their weight directly affects the end-effector's payload capacity and motion flexibility. By using lightweight materials in the aforementioned end-effector joints, the weight of the robotic arm's end effector can be effectively reduced while maintaining structural rigidity, which is beneficial for improving the end-effector's payload capacity and motion flexibility. Titanium alloy has advantages such as high specific strength and good corrosion resistance; aluminum alloy has advantages such as low density and good processing performance; and carbon fiber composite material has advantages such as high specific strength and specific modulus. Understandably, for the sake of overall material uniformity, all four joints 24 to seven joints 27 are made of a uniform lightweight material, such as aluminum alloy, and the connecting seat 1 and the first to third joints 23 are also made of a uniform lightweight material, such as aluminum alloy.

[0046] Furthermore, let's see together. Figure 6 and Figure 7 In some embodiments, the end effector 3 includes a mounting base 31, a pneumatic clamping device 32, and an air source input channel 33. The mounting base 31 serves as a support platform for the end effector 3 and is fixed to the end of the joint segment 2. The pneumatic clamping device 32 protrudes and is fixed to the mounting base 31 for quick connection to the sealing plug plate 50. The air source input channel 33 is located on the mounting base 31 and on the outer periphery of the pneumatic clamping device 32 for supplying air to the sealing plug plate 50. Optionally, the pneumatic clamping device 32 can be in the form of a pneumatic chuck, pneumatic gripper, or quick-change connector, etc., and can achieve quick docking and locking with the plug plate adapter 51 on the sealing plug plate 50 through pneumatic drive. By utilizing the specific spatial layout of the pneumatic clamping device 32 with its central clamping air supply channel 33 providing air to the outer periphery, the robotic arm can simultaneously grip the sealing plate 50 via the pneumatic clamping device 32 and supply power to the screwing unit 52 on the plate through the outer periphery air supply channel 33. This achieves synchronous gripping and power supply, eliminating the need for additional air lines after gripping the plate and simplifying the operation. Furthermore, this integrated design avoids spatial interference and motion coupling between the air lines and the clamping mechanism, ensuring the independence and reliability of both gripping and air supply functions.

[0047] Furthermore, in some embodiments, the air source input channel 33 includes a main air intake channel for connecting to an external air source and multiple branch air channels communicating with the main air intake channel. One end of the main air intake channel is used to connect to an external air source device, such as an air compressor or compressed air station, and the other end is connected to multiple branch air channels. The multiple branch air channels are arranged at intervals along the circumference of the pneumatic clamping device 32, and the outlet end of each branch air channel is respectively used to connect to the air intake channel of the plug adapter 51 on the sealing plug 50.

[0048] likeFigure 8 and Figure 9 As shown, a sealing plate adapter 51 is provided on the sealing plate 50. The sealing plate adapter 51 is used to realize quick connection and power transmission between the end working device 3 and the sealing plate 50. The sealing plate adapter 51 includes a mechanical connection structure for detachable connection with the end working device 3 and a power connection structure for receiving air source power.

[0049] The mechanical connection structure enables quick docking and locking between the end-effector 3 and the plug adapter 51, facilitating the handling of the sealing plug 50 by the end-effector 3. Specifically, the mechanical connection structure includes a mounting base 511, a connecting groove 512 on the mounting base 511, and multiple positioning holes 513. The connecting groove 512 is located in the center of the mounting base 511 and is used for quick insertion and engagement with the pneumatic clamping device 32. Multiple positioning holes 513 are spaced apart on the outer periphery of the connecting groove 512 and are used to engage with corresponding positioning pins on the mounting base 31 to achieve precise guidance and positioning during docking.

[0050] The power connection structure receives compressed air from the air source input channel 33 of the end-operated device 3 and transmits the compressed air to the air source drive device (such as the screwing unit 52) ​​on the sealing plate 50. Specifically, the power connection structure includes multiple air source input holes 514 and multiple air source output holes 515 provided on the mounting base 511. The multiple air source input holes 514 are spaced apart on the outer periphery of the connecting groove 512, and the position of each air source input hole 514 corresponds one-to-one with the outlet end of each branch air path of the air source input channel 33, so as to receive the compressed air delivered by each branch air path when the end-operated device 3 is connected to the plate adapter 51. The multiple air source output holes 515 are spaced apart on the side wall of the mounting base 511, so as to connect each air source drive device on the sealing plate 50, and each air source output hole 515 communicates with at least one air source input hole 514, thereby transmitting compressed air from the air source input hole 514 to the corresponding air source output hole 515.

[0051] Based on the above structure, when the end-effector 3 grips the sealing plate 50, that is, the pneumatic clamping device 32 is locked with the connecting groove 512, each positioning pin is inserted into the corresponding positioning hole 513 to complete the positioning, and at the same time, the outlet end of each branch air path is delivered to the corresponding air source input hole 514 for docking and connection. The air is output from the air source output hole 515 through the air passage inside the mounting base 511 to the air source drive device on the sealing plate 50, providing a power air source for the screwing unit 52 of the sealing plate 50. Since the branch air paths are arranged circumferentially along the pneumatic clamping device 32, and each outlet end corresponds one-to-one with the air source input hole 514 on the plate adapter 51, the end-effector 3 can complete the docking of all air paths at the same time as gripping the sealing plate 50, without the need for additional air path insertion and removal operations, realizing integrated gripping and ventilation operations.

[0052] Furthermore, in some embodiments, the pneumatic clamping device 32 includes a housing, a piston, an elastic reset member, and a plurality of balls. The housing has an axially extending piston chamber, and the sidewall of the housing has a plurality of ball holes communicating with the piston chamber, the ball holes being spaced apart circumferentially around the housing. The piston is slidably disposed within the piston chamber, one end of the piston having a tapered pushing surface, and the elastic reset member is disposed within the piston chamber and abuts against the piston and the housing. Each ball hole contains one ball, the diameter of which is larger than the diameter of the ball hole.

[0053] The housing has an air inlet communicating with the piston chamber, which is used to connect to an air source. When air is supplied, compressed air pushes the piston axially, and the conical pushing surface pushes each ball portion out of the ball hole, achieving radial expansion of the pneumatic clamping device 32. When pressure is released, the elastic reset member drives the piston to reset, and all the balls retract into the ball hole, achieving radial contraction of the pneumatic clamping device 32. The sealing plate adapter 51 on the sealing plate 50 has a connecting groove that mates with the pneumatic clamping device 32. The balls of the pneumatic clamping device 32 engage with the connecting groove; when a ball is partially pushed out, it engages in the connecting groove, achieving a locked connection; conversely, it unlocks.

[0054] Understandably, the specific structure of the pneumatic clamping device 32 described above is not shown in the figure. It is only one implementation method. As long as it can satisfy the radial expansion and radial contraction of the pneumatic clamping device, it can be locked and unlocked in accordance with the corresponding connection groove of the plug adapter 51.

[0055] Furthermore, in some embodiments, the end effector 3 further includes a visual positioning device, which is at least fixed to the mounting base 31. This device is used to acquire image information of the sealing plug 50 and the installation station 30 to provide feedback and guidance on the position of the end effector 3. In this embodiment, the visual positioning device can be an industrial camera with its lens facing forward of the end effector 3, used to capture images of the plug adapter 51 and the installation station 30. The visual positioning device transmits the acquired image information to an external control system. The control system calculates the deviation between the end effector 3 and the target position using a visual positioning algorithm and generates motion control commands for each joint of the joint segment 2, achieving closed-loop feedback control. The visual positioning device is not shown in the figure.

[0056] Example 2: See Figures 10 to 12 Another embodiment of the present invention also provides a method for disassembling and assembling sealing plates for nuclear power plant steam generators, using the robotic arm described above for disassembling and assembling sealing plates for nuclear power plant steam generators, the method comprising the following installation steps: S1: Adjust the joint segment 2 of the robotic arm to a folded state, reducing the radial envelope dimension of the robotic arm to less than the minimum passage dimension of the work inlet 20. Then, use the first conveying structure to send the robotic arm into the work space 10 through the work inlet 20. In this step, the robotic arm enters the evaporator water chamber through the manhole in a folded posture, ensuring that the cross-sectional dimensions of the robotic arm are within the Φ406mm manhole channel. Figure 10 As shown.

[0057] S2: Use the second conveying mechanism to send the sealing plate 50 into the working space 10 through the working inlet 20.

[0058] S3: After the robotic arm enters the workspace 10, each joint of the joint segment 2 moves the end effector 3 to the position of the sealing plate 50, achieving adapter locking and docking between the end effector 3 and the sealing plate 50, thus providing working power while gripping. In this step, after the robotic arm enters the workspace 10, guided by the vision positioning device, the end effector 3 is accurately aligned with the sealing plate 50, and rapid docking and locking are achieved through the pneumatic clamping device 32. Figure 11 As shown. Working power can be input through air source input channel 33. For details, please refer to the detailed description of air source input channel 33 above, which will not be repeated here.

[0059] S4: Joint segment 2 transports the end effector 3 carrying the sealing plug 50 to the target installation station 30. After the sealing plug 50 is aligned with the pipe seat, the tightening unit 52 on the sealing plug 50 is driven by an air source to tighten the fastening bolts, completing the locking installation of the sealing plug 50. In this step, the robotic arm, in conjunction with a vision system and positioning algorithm, achieves precise alignment and positioning between the sealing plug 50 and the primary coolant inlet / outlet or condensate drain hole. Then, the air source drive device on the sealing plug 50 automatically completes the fastening installation of the sealing plug 50. Figure 12 As shown.

[0060] See Figure 10 Furthermore, in step S1, adjusting the joint segment 2 of the robotic arm to a folded state specifically includes: adjusting the fourth joint 24, the fifth joint 25, the sixth joint 26, the seventh joint 27, and the end effector 3 to a horizontal position, driving the third joint 23 to rotate so that the joint segment 2 as a whole is in a folded position, and making the cross-sectional dimension envelope of the joint segment 2 smaller than the passage dimension of the work entrance 20. In this embodiment, when the robotic arm passes through the manhole, the fourth joint 24, the fifth joint 25, the sixth joint 26, the seventh joint 27, and the end effector 3 are adjusted to a horizontal position, and then the third joint 23 is rotated to adjust the robotic arm to a folded position. At this time, the maximum horizontal dimension is 1450mm, and the cross-sectional dimension envelopes the Φ406mm manhole passage.

[0061] The robotic arm is conveyed into the workspace 10 via the first conveying structure. Once the fourth joint 24 enters the work inlet 20, the first joint 21, third joint 23, and fourth joint 24 are driven to rotate collaboratively, causing each arm segment of joint 2 to gradually arch, reducing the axial dimension of joint segment 2 until the end-effector 3 completely passes through the work inlet 20. In this embodiment, after the fourth joint 24 enters the manhole, i.e., when the robotic arm's entry dimension is ≥820mm, the angles of the first joint 21, third joint 23, and fourth joint 24 are adjusted. At this time, each arm segment of the robotic arm entering the water chamber gradually arches, thereby reducing the axial dimension (1450mm in this embodiment) until the end-effector 3 completely passes through the manhole. The robotic arm is directly connected to the primary conveying mechanism; after being folded and sent into the water chamber, it can achieve full-range operation with a radius of 1450mm without the need for additional anchor points. Further, see... Figure 10 In some embodiments, the method further includes the following disassembly steps: S5: Joint segment 2 sends the end effector 3 into the working space 10 through the working inlet 20. Guided by the visual positioning device, the end effector 3 is locked and connected to the adapter of the sealing plate 50, while providing working power. In this step, the robotic arm enters the water chamber through the manhole in a folded state, then unfolds and moves to the installation station 30 where the sealing plate has been installed.

[0062] S6: The screwing unit 52 of the sealing plate 50, driven by an air source, loosens the fasteners of the sealing plate 50 in the opposite direction, thereby detaching the sealing plate 50 from the pipe seat. The end effector 3 then carries the sealing plate 50 away from the pipe seat. In this step, the robotic arm first grasps the sealing plate using the pneumatic clamping device 32, and then supplies air to the air source drive device through the sealing plate adapter 51 to drive the air source drive device for disassembly. This disassembly of the sealing plate 50 also prevents it from accidentally falling off after all the bolts have been loosened.

[0063] S7: The end-effector 3 reaches the target position (i.e., near the manhole) of the adjacent work entrance 20 through a preset motion path, places the sealing plate 50 on the plate tray, and the second conveying mechanism transports the plate on the plate tray and the sealing plate 50 out of the work entrance 20.

[0064] S8: Adjust joint segment 2 to a folded state so that the radial envelope dimension of the robotic arm is reduced to less than the maximum passage dimension of the work entrance 20, and the first conveying structure exits joint segment 2 from the work space 10 through the work entrance 20.

[0065] By implementing this invention, the following beneficial effects are achieved: This invention relates to a robotic arm for the installation and removal of sealing plates in nuclear power plant steam generators. The robotic arm comprises seven degrees of freedom and has folded and extended states. In the folded state, the robotic arm can enter the work space through a narrow inlet with a limited diameter, maintaining a compact folded posture. In the extended state, the reach of the end effector 3 can cover the installation position of the sealing plate. The ample degrees of freedom allow the robotic arm to flexibly adjust its posture after entering the work space, precisely reaching the target position and meeting the needs of large-scale operations. Simultaneously, the end effector 3, in conjunction with the robotic arm, automates the entire installation process of the sealing plate 50, reducing the radiation dose to operators in the radiation environment.

[0066] The present invention provides a method for the disassembly and assembly of sealing plugs in nuclear power plant steam generators. Based on the structure of a robotic arm, the method further defines the specific operation process for the installation of the sealing plug 50, enabling operators to operate the robotic arm in a clear step sequence to complete the remote automated installation of the sealing plug 50. This improves work efficiency and reliability and reduces the radiation dose to operators in the radiation environment.

[0067] It is understood that the above embodiments only illustrate preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that for those skilled in the art, the above embodiments or technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present invention. These all fall within the protection scope of the present invention. That is, the embodiments described "in some embodiments" can be freely combined with any of the embodiments above and below. Therefore, all equivalent transformations and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A robotic arm for disassembling and assembling sealing plates of steam generators in nuclear power plants, characterized in that, It includes a connecting seat (1), a joint segment (2), and an end-effector (3) for integrating gripping and power supply functions; the two ends of the joint segment (2) are respectively connected to the connecting seat (1) and the end-effector (3), and the connecting seat (1) is used to connect to the first conveying structure; The joint segment (2) includes multiple degrees of freedom and has a folded state and an unfolded state. In the folded state, the rear arm segment of the joint segment (2) is folded together with the forearm segment, so that the forearm segment and the rear arm segment overlap and the overall radial envelope size of the robotic arm is reduced to less than the maximum passage size of the work entrance (20). In the unfolded state, the reachable range of the end working device (3) covers all the installation positions (30) of the sealing plate (50).

2. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to claim 1, characterized in that, The joint segment (2) includes at least seven degrees of freedom, and the joint segment (2) includes a first joint (21), a second joint (22), a third joint (23), a fourth joint (24), a fifth joint (25), a sixth joint (26), and a seventh joint (27) connected in sequence. The first joint (21) is a forward joint that rotates about a first axis to rotate forward relative to the connecting seat (1); the second joint (22) is a lateral joint that rotates about a second axis to rotate laterally relative to the connecting seat (1); the third joint (23) is a pitch joint that rotates about a third axis to drive the overall pitch rotation of the fourth joint (24), the fifth joint (25), the sixth joint (26), and the seventh joint (27); the first axis and the second axis are spatially perpendicular to each other and spatially parallel to each other with the third axis; The fourth joint (24), the fifth joint (25), the sixth joint (26) and the seventh joint (27) are connected sequentially between the third joint (23) and the end effector (3) to adjust the end posture of the end effector (3) relative to the third joint (23).

3. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to claim 2, characterized in that, In the unfolded state, the entire first joint (21) and the entire second joint (22) are disposed on opposite sides of the third joint (23) along with the entire fourth joint (24), the fifth joint (25), the sixth joint (26) and the seventh joint (27); In the folded state, the entirety of the first joint (21) and the second joint (22) is disposed on one side of the third joint (23) and overlaps with the entirety of the fourth joint (24), the fifth joint (25), the sixth joint (26) and the seventh joint (27).

4. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to claim 2, characterized in that, The third joint (23) is a heavy-duty joint, which adopts a worm gear transmission structure to bear the gravity load of the fourth joint (24) to the seventh joint (27), the end working device (3) and the sealing plate (50).

5. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to claim 4, characterized in that, The third joint (23) includes a mounting shell (231), a third motor (232), a worm (233), a worm wheel (234), a rotating shaft (235), and a tilting shaft (236). The third motor (232), the worm (233), and the worm wheel (234) are all located inside the mounting shell (231). The output shaft of the third motor (232) is connected to the worm (233). The worm (233) is meshed with the worm wheel (234). The rotating shaft (235) is fixedly connected to the worm wheel (234), and both ends of the rotating shaft (235) extend out of the mounting shell (231) and are respectively connected to the tilting shaft (236). The third motor (232) drives the worm gear (233) to rotate, and the worm gear (233) drives the worm wheel (234) to rotate, which synchronously transmits the power to the rotating shaft (235) and the flipping shaft (236). The other end of the flipping shaft (236) is connected to the fourth joint (24), thereby driving the fourth joint (24) to the seventh joint (27) to flip as a whole, and finally realizing the folded state or unfolded state of the joint segment (2).

6. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to claim 4, characterized in that, The single-stage transmission ratio of the worm gear transmission structure of the third joint (23) is 20~40, the module is 4~8, and the external dimensions of the worm gear transmission structure are set such that the cross-sectional dimensions of the joint segment (2) are smaller than the through dimensions of the working entrance (20).

7. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to any one of claims 1-6, characterized in that, The end working device (3) includes a mounting base (31), a pneumatic clamping device (32), and an air source input channel (33). The pneumatic clamping device (32) protrudes and is fixed on the mounting base (31) for quick connection of the sealing plate (50). The air source input channel (33) is located on the mounting base (31) and on the outer periphery of the pneumatic clamping device (32) for supplying air source to the sealing plate (50).

8. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to claim 7, characterized in that, The air source input channel (33) includes an air intake main channel connected to an external air source and multiple branch air channels connected to the air intake main channel. The multiple branch air channels are arranged at intervals along the circumference of the pneumatic clamping device (32). The outlet end of each branch air channel is respectively used to connect to multiple screwing units (52) on the sealing plate (50) to provide a power air source for each screwing unit (52) when the end working device (3) grips the sealing plate (50).

9. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to claim 7, characterized in that, The pneumatic clamping device includes a housing, a piston, an elastic reset member, and multiple balls. The housing has an axially extending piston cavity, and the sidewall of the housing has multiple ball holes communicating with the piston cavity. These ball holes are spaced apart circumferentially around the housing. The piston is slidably disposed within the piston cavity, and one end of the piston has a tapered pushing surface. The elastic reset member is disposed within the piston cavity and abuts against the piston and the housing. Each ball hole contains one ball, and the diameter of the ball is larger than the diameter of the ball hole. The housing is provided with an air inlet communicating with the piston chamber, and the air inlet is used to connect to an air source; when air is supplied, compressed air pushes the piston to move axially, and the conical pushing surface pushes each of the ball parts out of the ball hole to realize the radial expansion of the pneumatic clamping device; when pressure is released, the elastic reset member drives the piston to reset, and all the balls retract into the ball hole to realize the radial contraction of the pneumatic clamping device.

10. The robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator according to claim 7, characterized in that, The end-effector (3) further includes a visual positioning device, which is fixed at least on the mounting base (31) and is used to collect image information of the sealing plate (50) and the installation station (30) to provide feedback and guidance on the position of the end-effector (3).

11. A method for disassembling and assembling sealing plates for steam generators in nuclear power plants, characterized in that, Using the robotic arm for disassembling and assembling sealing plates of a nuclear power plant steam generator as described in any one of claims 1 to 10, the method includes the following installation steps: S1: Adjust the joint segment (2) of the robotic arm to a folded state, so that the radial envelope dimension of the robotic arm is reduced to less than the maximum passage dimension of the work entrance (20), and then use the first conveying structure to send the robotic arm into the work space (10) through the work entrance (20); S2: Use the second conveying mechanism to send the sealing plate (50) into the working space (10) through the working inlet (20); S3: After the robotic arm enters the work space (10), each joint of the joint segment (2) moves the end working device (3) to the position of the sealing plate (50), so as to lock and connect the adapter of the end working device (3) and the sealing plate (50) to achieve grasping and provide working power at the same time. S4: The joint segment (2) transports the end working device (3) carrying the sealing plug (50) to the target installation position (30). After the sealing plug (50) is aligned with the pipe seat, the screwing unit (52) on the sealing plug (50) is driven by the air source to screw the fastening bolts, thus completing the locking installation of the sealing plug (50).

12. The method for disassembling and assembling sealing plates for steam generators in nuclear power plants according to claim 11, characterized in that, In step S1, adjusting the joint segment (2) of the robotic arm to a folded state specifically includes: Adjust the fourth joint (24), fifth joint (25), sixth joint (26), seventh joint (27) and end working device (3) to a horizontal position, drive the third joint (23) to rotate so that the joint segment (2) is in a folded position as a whole, and make the cross-sectional size envelope of the joint segment (2) smaller than the through size of the working entrance (20); The robotic arm is conveyed into the work space (10) through the first conveying structure. When the fourth joint (24) enters the work entrance (20) as a whole, the first joint (21), the third joint (23) and the fourth joint (24) are driven to rotate in coordination, so that each arm segment of the joint segment (2) gradually arches up to reduce the axial dimension of the joint segment (2) until the end working device (3) completely passes through the work entrance (20).

13. The method for disassembling and assembling sealing plates for steam generators in nuclear power plants according to claim 11, characterized in that, The following disassembly steps are also included: S5: The joint segment (2) sends the end working device (3) into the working space (10) through the working inlet (20), and guides it through the visual positioning device to realize the locking docking of the end working device (3) with the adapter of the sealing plate (50), while providing working power; S6: The screwing unit (52) of the sealing plate (50) is driven by the air source to loosen the fastener of the sealing plate (50) in the opposite direction, so that the sealing plate (50) is separated from the pipe seat, and the end working device (3) carries the sealing plate (50) away from the pipe seat. S7: The end working device (3) reaches the target position near the work entrance (20) through a preset movement path, places the sealing plate (50) on the plate tray, and the second conveying mechanism transports the plate placed on the plate tray and the sealing plate (50) out of the work entrance (20); S8: Adjust the joint segment (2) to a folded state, so that the radial envelope dimension of the robotic arm is reduced to less than the maximum passage dimension of the work entrance (20), and the first conveying structure exits the joint segment (2) through the work entrance (20) into the work space (10).

Images