A multi-stage telescopic sleeve mechanism of a nuclear power plant charging and discharging machine

Abstract

The present application relates to the technical field of loading and unloading machine, especially to a multi-stage telescopic sleeve mechanism of a nuclear power plant loading and unloading machine, which comprises an outer sleeve, an inner sleeve and at least one intermediate layer sleeve between the outer sleeve and the inner sleeve, the remaining sleeves outside the inner sleeve are provided with an on-off type automatic stop block device, and the remaining sleeves outside the inner sleeve are kept in a static state by the blocking and limiting of the on-off type automatic stop block device; the present application solves the problem that the telescopic sleeve stroke of deep core fuel operation is relatively long and the fixed sleeve cannot be relatively long due to process limitations; the problem that the fuel assembly cannot be loaded and unloaded because the multi-stage telescopic sleeve fuel assembly is still located in the second outer layer sleeve at a non-core station is solved; and the problem of the verticality and positioning accuracy of the multi-stage sleeve is solved.

Description

Technical Field

[0001] This invention relates to the field of loading and unloading machine technology, and in particular to a multi-stage telescopic sleeve mechanism for a nuclear power plant loading and unloading machine. Background Technology

[0002] Fuel loaders are used in nuclear power plants to load and unload fuel assemblies from the reactor core and transfer fuel assemblies between the reactor core and the transfer device. The lifting mechanism of a pressurized water reactor nuclear power plant fuel loader includes an outer sleeve and an inner sleeve. The outer sleeve is fixed to a trolley, and the inner sleeve moves up and down along a guide rail inside the outer sleeve. The two-stage telescopic sleeve structure of the inner and outer sleeves enables precise positioning of the fuel loader within the reactor core and the grabbing of fuel assemblies.

[0003] Currently, the inner sleeve stroke of the refueling machine in domestic pressurized water reactor nuclear power plants is generally no more than 9m, and the inner sleeve can guide the entire stroke within the outer sleeve. For some new reactor types, such as integrated small reactors, the core depth is greater. If the existing two-stage sleeve design of the refueling machine is adopted, the inner sleeve stroke needs to be doubled, and the outer sleeve, which serves as the guide sleeve, also needs to be lengthened accordingly. According to the reactor pool layout, the outer sleeve needs to pass over the upper flange face of the reactor pressure vessel, the upper plane of the fuel basket of the fuel transfer device, and the upper plane of the fuel storage rack. The upper elevation of these working positions limits the lower elevation of the outer sleeve of the refueling machine, thus limiting the length of the outer sleeve. The two-stage telescopic sleeve is not suitable for the operation of fuel assemblies in deep cores. At the same time, the spacing between core fuel assemblies is only 1mm, and the fuel assemblies undergo certain deformation and bending after burnup, requiring guaranteed positioning accuracy. Existing inner and outer sleeve type refueling machines cannot meet the requirements of the refueling process.

[0004] Furthermore, industrial cranes include multi-stage sleeve cranes with more than two stages, all of which retract progressively from the inside out and extend progressively from the outside in, with the innermost sleeve extending last. In nuclear power plant refueling cranes, to protect fuel assemblies, the fuel assemblies must retract completely into the outer sleeve along with the innermost sleeve to prevent collisions with surrounding objects during horizontal movement of the refueling crane. If a multi-stage sleeve crane is used, when the multiple sleeves descend, the non-core working position is higher than the core position elevation. The fuel assembly located in the innermost sleeve will still be within the next outermost sleeve, making unloading of the fuel assembly impossible. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a multi-stage telescopic sleeve mechanism for nuclear power plant refueling machines. This mechanism satisfies both the requirement for the gripper to reach a specified depth and the requirement that the outer sleeve, after retraction, can pass over the upper surfaces of fuel storage racks, fuel transport equipment, and fuel baskets. To achieve this objective, the invention employs the following technical solution:

[0006] The present invention provides a multi-stage telescopic sleeve mechanism for a nuclear power plant loading and unloading machine, including an outer sleeve, an inner sleeve, and at least one intermediate layer sleeve located between the two. The remaining sleeves outside the inner sleeve are equipped with an on / off automatic stop device, which blocks and restricts the remaining sleeves outside the inner sleeve to keep them in a stationary state.

[0007] As a further implementation, the switch-type automatic stop device includes a turntable structure and an active link and a driven link connected to the turntable structure. The driven link is equipped with a stop, and the remaining sleeve drives the active link to rotate the turntable structure through up-and-down movement, thereby driving the stop to be limited through the driven link.

[0008] As a further implementation, the turntable structure includes an active turntable and a passive turntable, wherein the active turntable is connected to the active linkage and the passive turntable is connected to the passive linkage.

[0009] As a further implementation, the turntable structure rotates in one direction, the transmission ratio between the active turntable and the driven turntable is 2:1, and the active turntable and the driven turntable form a planetary gear structure.

[0010] As a further implementation, one end of the active linkage drives the active turntable to rotate one revolution through vertical up-down movement, and the driven turntable drives the driven linkage to move the stop block horizontally into the limit state.

[0011] As a further implementation, when the end of the active link moves up and down to the upper limit position, the extension line passes through the rotation axis of the turntable structure.

[0012] As a further implementation, except for the inner sleeve which is a square sleeve, all other sleeves are round sleeves.

[0013] As a further implementation, the remaining sleeve is configured with a plurality of support structures for supporting the secondary sleeve, the support structure including two inclined surfaces arranged vertically.

[0014] As a further implementation, the remaining sleeves are configured with multiple guide structures, the guide structures including guide rails on the secondary sleeves and guide wheels on the outer sleeves, the gap between the guide wheels and the bottom surface of the guide rails being adjustable.

[0015] As a further implementation, the remaining sleeves are configured with multiple anti-sway structures, each including an anti-sway guide wheel disposed on the outer sleeve and located on the side of the guide rail of the secondary sleeve, for limiting the circumferential rotation of the secondary sleeve.

[0016] The beneficial effects of the present invention are as follows:

[0017] (1) This invention features a switch-type automatic stop device, eliminating the need for additional external active components. The outer telescopic sleeve is simply raised to trigger the stop switch device, causing the stop to insert. The outer telescopic sleeve remains on the stop, while the inner sleeve extends with the fuel assembly. Raising the outer telescopic sleeve again triggers the stop switch device, causing the stop to retract and allowing the outer telescopic sleeve to descend freely. This solves the problem of the innermost sleeve needing to extend first in multi-stage telescopic sleeves, and addresses the issue that the outer sleeve of traditional two-stage loading and unloading machines with inner and outer sleeves cannot meet the requirements of plant layout and loading / unloading processes.

[0018] (2) This invention achieves guidance, prevention of circumferential rotation, and connection between sleeves by setting up a guide structure, an anti-sway structure, and a support structure. The support structure uses a wedge-shaped inclined plane to adjust the support height, ensuring that the four circumferential support structures are on the same plane, guaranteeing the verticality of the inner sleeve. The guide wheel is radially adjustable; by adjusting the gap between the guide wheel and the guide rail, the verticality of the inner sleeve is achieved, and the vertical movement is smooth. The anti-sway guide wheel is adjustable, ensuring that its cylindrical side only contacts the side of the guide rail, not the bottom of the guide rail groove, thus preventing circumferential rotation and avoiding jamming of the guide rail. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0020] Figure 1 This is a schematic diagram of the multi-stage sleeve in the embodiment of the present invention with all stages extended.

[0021] Figure 2 This is a schematic diagram of the multi-stage sleeve in its fully retracted state in an embodiment of the present invention.

[0022] Figure 3 This is an embodiment of the present invention. Figure 2 Diagram of direction A in the middle.

[0023] Figure 4 This is an embodiment of the present invention. Figure 2 Schematic diagram of direction B in the middle.

[0024] Figure 5 This is a schematic diagram of the positioning and guiding device in an embodiment of the present invention.

[0025] Figure 6 This is a schematic diagram of the support structure in an embodiment of the present invention.

[0026] Figure 7 This is a schematic diagram of the anti-sway structure in an embodiment of the present invention.

[0027] Figure 8 This is a schematic diagram of the guide structure in an embodiment of the present invention.

[0028] Figure 9 This is a schematic diagram of the switch-type automatic stop device in an embodiment of the present invention.

[0029] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.

[0030] The components are: 1. Outer sleeve; 2. First intermediate sleeve; 3. Second intermediate sleeve; 4. Inner sleeve; 5. Support structure; 51. First inclined surface; 52. Second inclined surface; 6. Anti-sway structure; 61. Anti-sway guide wheel; 7. Guide structure; 71. Guide wheel; 8. Switching device; 9. Spring; 10. Driving linkage; 11. Other sleeves; 12. Driven turntable; 13. Driving turntable; 14. Driven linkage; 15. Stop block. Detailed Implementation

[0031] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0032] In a typical embodiment of the present invention, reference is made to Figures 1-9 As shown, a multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine includes an outer sleeve 1, an inner sleeve 4, and at least one intermediate layer sleeve located between them. In this embodiment, two intermediate layer sleeves are provided: a first intermediate layer sleeve 2 and a second intermediate layer sleeve 3. It is understood that in some other embodiments, the number of intermediate layer sleeves is not limited to the number in this embodiment. The length of the outer sleeve 1 meets the requirement of extending beyond the upper surface of the working position, and the length of each sleeve is contained within the upper sleeve. Except for the inner sleeve 4, which is a square sleeve, the other sleeves 11 are all circular sleeves. The square design of the inner sleeve 4 of the multi-stage sleeve meets the requirement of limited space inside the reactor pressure vessel during deep core operation. This enables operation of fuel assemblies near the core enclosure.

[0033] like Figure 1 As shown, in the fully extended state, the secondary sleeve rests on the support structure 5 of its outer sleeve. An overlap is required between the two sleeves, with at least two sets of guide wheels 71 at different heights to ensure guidance throughout the entire stroke of the secondary sleeve. The minimum length of the overlap is sufficient to satisfy the guiding function of the two sets of guide wheels 71. For the inner sleeve 4, since it needs to carry the fuel assembly into the middle two sleeves, the overlap is the length of the fuel assembly plus the minimum overlap length required for the two sets of guide wheels.

[0034] like Figure 2As shown, in the fully contracted state, the secondary sleeve rests on the lower flange face of its outer sleeve and rises upwards step by step, with the secondary sleeve enveloping its outer sleeve. The length of the sleeve is determined by the elongation of the secondary sleeve and the required overlap length.

[0035] like Figure 9 As shown, the remaining sleeves 11 outside the inner sleeve 4 are equipped with an on / off automatic stop device 15. The on / off automatic stop device 15 restricts the movement of the remaining sleeves 11 outside the inner sleeve 4 to maintain a stationary state. The on / off automatic stop device 15 is used when the sleeves are in a non-core working position, with the sleeve extension length in the middle position. The intermediate sleeve does not need to extend; only the inner sleeve 4 extends. It should be noted that, in this specification, all sleeves other than the inner sleeve 4 are referred to as the remaining sleeves 11, which include the outer sleeve 1 and the intermediate layer sleeve.

[0036] The automatic stop block 15 device includes a turntable structure and an active connecting rod 10 and a driven connecting rod 14 connected to the turntable structure. The driven connecting rod 14 is equipped with the stop block 15. The remaining sleeves 11 drive the active connecting rod 10 to rotate the turntable structure through up-and-down movement, thereby driving the stop block 15 to be limited through the driven connecting rod 14. The automatic stop block 15 lifting trigger switch 8 drives the stop block 15 to be inserted and removed through a transmission chain. The turntable structure includes an active turntable 13 and a driven turntable 12. The active turntable 13 is connected to the active connecting rod 10, and the driven turntable 12 is connected to the driven connecting rod 14. Specifically, one end of the active connecting rod 10 is located inside the switch device 8, and the compression spring 9 always acts on the enabling end of the active connecting rod 10. The other end of the active connecting rod 10 is hinged to the active turntable 13. The enabling end of the active connecting rod 10 translates between position B and position A within the stop block switch device, and both positions have a stop limit. The other end of the driving link 10 drives the driving turntable 13 to rotate. The driving turntable 13 drives the driven turntable 12 to rotate, with a transmission ratio of 2:1, meaning that the driven turntable 12 rotates half a turn for every one revolution of the driving turntable 13. The driving turntable 13 is equipped with a backstop mechanism, allowing only unidirectional rotation. One end of the driven link 14 is hinged to the stop block 15, and the other end is hinged to the driven turntable 12. When the driven turntable 12 rotates, it drives the stop block 15 to insert and retract through the driven link 14.

[0037] like Figure 9 As shown, in this embodiment, the active turntable and the driven turntable form a planetary gear structure. The active turntable 13 is equivalent to a sun gear structure, and the driven turntable 12 is equivalent to a gear ring structure. The active turntable 13 rotates with the driven turntable 12 through the planetary gear. In this embodiment, the planetary gear can rotate along its own axis.

[0038] The working method of the switch-type automatic stop device 15 is as follows:

[0039] (1) The remaining sleeves 11 are raised to the switch device 8, and the active linkage 10 in position B is raised. After rising to position A, the remaining sleeves 11 are lowered.

[0040] (2) When the enable end of the active link 10 moves from position B to position A, it drives the active turntable 13 to rotate. When the other sleeves 11 descend, the compression spring 9 moves the enable end of the active link 10 from A to B. Since the extension line of the link at position A passes through the center of the axis of the active turntable 13 and the active turntable 13 can only rotate in one direction, the active turntable 13 continues to rotate in the original direction. When the enable end of the active link 10 reaches position B, the active turntable 13 rotates one revolution.

[0041] (3) When the driving turntable 13 rotates one revolution, the driven turntable 12 rotates half a revolution, and the stop block 15 is... Figure 9 The solid line position (contraction position) shown reaches the dashed line position (insertion position), and the remaining sleeves 11 are placed on the stop block 15.

[0042] (4) When opening is required, the remaining sleeves 11 are lifted, the enabling end of the driving linkage 10 completes one round trip, the driving turntable 13 rotates one revolution, the driven turntable 12 rotates half a revolution, and the stop block 15 returns to its original position. Figure 9 The solid line position (contraction position) allows the remaining sleeves 11 to descend freely.

[0043] This embodiment features a switch-type automatic stop device, eliminating the need for additional external moving parts. Simply lifting the outer telescopic sleeve triggers the stop switch, inserting the stop. The outer telescopic sleeve remains on the stop, while the inner sleeve extends with the fuel assembly. Lifting the outer telescopic sleeve again triggers the stop switch, causing the stop to retract and allowing the outer telescopic sleeve to descend freely. This solves the problem of the innermost sleeve needing to extend first in multi-stage telescopic sleeve systems, addressing the issue that traditional two-stage loading and unloading machines with inner and outer sleeves cannot meet the requirements of plant layout and loading / unloading processes.

[0044] like Figure 3 , Figure 4 , Figure 5 As shown, the multi-stage telescopic sleeve is also equipped with a support structure 5, an anti-sway structure 6, and a guide structure 7.

[0045] The remaining sleeves 11 are equipped with multiple support structures 5 for supporting the secondary sleeves, and the arrangement of the support structures 5 is as follows: Figure 6 As shown, the support structure 5 includes two inclined surfaces arranged vertically, a first inclined surface 51 and a second inclined surface 52. There are four support structures at each stage, evenly distributed on the sleeve wall, used to support the secondary sleeve. When the secondary sleeve is lowered into position, it rests on the support structure 5. The support structure 5 adopts an inclined surface mating structure; the height of the support structure 5 is adjusted by adjusting the relative positions of the two inclined surfaces with adjusting screws, ensuring that the secondary sleeve is simultaneously supported on four support blocks while maintaining the required verticality.

[0046] like Figure 8 As shown, the remaining sleeves 11 are equipped with multiple guide structures 7. Each guide structure 7 includes a guide rail on the secondary sleeve and guide wheels 71 on the outer sleeve. The gap between the guide wheels 71 and the bottom surface of the guide rail is adjustable. The guide wheels are mounted on the outer sleeve, and the guide rail is mounted on the outer wall of its inner sleeve. In this embodiment, the sleeve is provided with four sets of guide wheels, evenly distributed circumferentially on the sleeve wall. The guide wheels 71 of adjacent sleeves are staggered at 45-degree intervals to facilitate compact spatial arrangement. The guide wheels 71 roll up and down along the guide rail, with a gap between the side of the guide wheel 71 and the guide rail to prevent jamming. The guide wheels 71 are radially adjustable within the sleeve; by adjusting the fastening bolts or adjusting pins, the verticality requirements of the secondary sleeve are met, and smooth up-and-down movement is ensured.

[0047] like Figure 7 As shown, the remaining sleeves 11 are equipped with multiple anti-sway structures 6. Each anti-sway structure 6 includes an anti-sway guide wheel 61 mounted on the outer sleeve and located on the side of the guide rail of the secondary sleeve, used to restrict the circumferential rotation of the secondary sleeve. The anti-sway guide wheel 61 and the guide wheel 71 are arranged on the same axis and share a guide rail. The anti-sway guide wheel 61 has a cylindrical structure in contact with the side of the guide rail, used to restrict the circumferential rotation of the secondary sleeve. The gap between the anti-sway guide wheel 71 and the bottom surface of the guide rail can be adjusted by adjusting the connecting bolts of the anti-sway guide wheel 71 and by adding or removing shims to ensure that it does not contact the bottom surface of the rail, allowing the secondary sleeve to move smoothly up and down.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine, characterized in that, It includes an outer sleeve, an inner sleeve, and at least one intermediate layer sleeve located between the two. The remaining sleeves outside the inner sleeve are equipped with an on / off automatic stop device, which blocks and restricts the remaining sleeves outside the inner sleeve to keep them in a stationary state. The switch-type automatic stop device includes a turntable structure and an active link and a driven link connected to the turntable structure. The driven link is equipped with a stop. The remaining sleeve drives the active link to rotate the turntable structure through up-and-down movement, and then drives the stop to limit the position through the driven link. The turntable structure includes an active turntable and a driven turntable; One end of the active linkage is located inside the switching device, and the compression spring always acts on the enabling end of the active linkage. The other end of the active linkage is hinged to the active turntable. The enabling end of the active linkage moves between position B and position A within the stop switch device, with a stop limit in both positions. The other end of the active linkage drives the active turntable to rotate. The active turntable drives the driven turntable to rotate, with a transmission ratio of 2:1, meaning that the driven turntable rotates half a turn for every one revolution of the active turntable. The active turntable is equipped with a backstop mechanism, allowing only unidirectional rotation. One end of the driven linkage is hinged to the stop block, and the other end is hinged to the driven turntable. When the driven turntable rotates, it drives the stop block to insert and retract through the driven linkage.

2. The multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine according to claim 1, characterized in that, The active turntable and the driven turntable form a planetary gear structure.

3. The multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine according to claim 1, characterized in that, One end of the active linkage drives the active turntable to rotate one revolution through vertical up-down movement, and the driven turntable drives the driven linkage to move the stop block horizontally into the limit state.

4. The multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine according to claim 3, characterized in that, When the end of the active connecting rod moves up and down to the upper limit position, the extension line passes through the rotation axis of the turntable structure.

5. The multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine according to claim 1, characterized in that, Except for the inner sleeve, which is a square sleeve, all other sleeves are round sleeves.

6. The multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine according to claim 1, characterized in that, The remaining sleeves are equipped with multiple support structures for supporting the secondary sleeves, and the support structures include two inclined surfaces arranged vertically.

7. The multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine according to claim 1, characterized in that, The remaining sleeves are equipped with multiple guide structures, including a guide rail on the secondary sleeve and a guide wheel on the outer sleeve, the gap between the guide wheel and the bottom surface of the guide rail being adjustable.

8. A multi-stage telescopic sleeve mechanism for a nuclear power plant refueling machine according to claim 7, characterized in that, The remaining sleeves are equipped with multiple anti-sway structures, each including an anti-sway guide wheel disposed on the outer sleeve and located on the side of the guide rail of the secondary sleeve, for limiting the circumferential rotation of the secondary sleeve.

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