Nuclear underwater limit switch

Abstract

The application provides a nuclear underwater limit switch, which comprises a main body shell, a joint shell, a lead-out wire, multiple sets of redundant contact action mechanisms and an isolation component. The multiple sets of redundant contact action mechanisms are respectively located in multiple independent chambers in a cavity surrounded by the main body shell and the joint shell, and are respectively configured to be disconnected from the lead-out wire in an initial state and connected to the lead-out wire to output a contact point signal in a detection state of detecting a detected object. All cables in the multiple sets of redundant contact action mechanisms are connected to the lead-out wire to transmit the contact point signal through the lead-out wire. The isolation component is configured to isolate two adjacent sets of redundant contact action mechanisms to make the multiple sets of redundant contact action mechanisms independent of each other. The application improves the reliability of the nuclear underwater limit switch through single-body multi-channel redundant design of a single nuclear underwater limit switch.

Description

Technical Field

[0001] This application belongs to the technical field of underwater mobile mechanical mechanisms, specifically relating to a nuclear-use underwater limit switch. Background Technology

[0002] Submersible limit switches (also known as limit switches used in nuclear power plant-related pools, or underwater limit switches used in extreme environments of nuclear equipment pools) are mainly used in nuclear power plants for monitoring the position of underwater moving mechanical mechanisms and controlling the system in nuclear equipment-related pools. When the moving mechanical mechanism reaches a set travel distance, the switch output contact state needs to be flipped; that is, the on / off state of the contact needs to change according to the mechanical travel state. The feedback control system uses this to control the equipment state, thereby achieving the precise control requirements of its position.

[0003] Submersible limit switches play a crucial role in controlling the travel distance of underwater moving machinery within the water tank, determining the precise distance the machinery can travel. A switch malfunction will prevent the machinery from reaching the required position or fulfilling its feedback control function, directly rendering the equipment unusable or causing unacceptable consequences.

[0004] Nuclear power plant underwater limit switches typically employ imported magnetic induction single-channel limit switches, such as proximity sensor limit switches. These switches use quick-connect connectors at the rear end and lack physical redundancy. Due to prolonged immersion in boric acid solutions, high-radiation-dose areas, and high-pressure deep water pools, the reliability of single-channel switches is compromised. Damage requires lengthy drainage and replacement, or replacement may not be feasible at all, significantly impacting the operational safety and economic efficiency of nuclear power plant equipment.

[0005] Currently, underwater limit switches used in the extreme environments of nuclear power plant nuclear equipment pools are all single-channel designs, both in the international and domestic markets, which cannot meet the high reliability safety requirements for underwater applications. Summary of the Invention

[0006] In view of this, the embodiments of this application are committed to providing a nuclear-use underwater limit switch. By implementing a single-entry multi-redundant design for a single nuclear-use underwater limit switch, that is, by employing multiple sets of redundant contact action mechanisms in a single nuclear-use underwater limit switch, the problem that the existing single-entry nuclear-use underwater limit switch design cannot meet the safety requirements of high reliability underwater is solved.

[0007] This application provides a nuclear-use underwater limit switch, which includes a main body housing, a connector housing, outgoing wires, multiple sets of redundant contact actuation mechanisms, and an isolation component. The main body housing has a first opening. The connector housing is embedded within the first opening and has a second opening. The outgoing wires are sealed at the second opening. The multiple sets of redundant contact actuation mechanisms are located in multiple independent chambers within a cavity enclosed by the main body housing and the connector housing. Each set of redundant contact actuation mechanisms is configured to be disconnected from the outgoing wires in an initial state and connected to the outgoing wires in a detection state to output contact signals. All cables in the multiple sets of redundant contact actuation mechanisms are connected to the outgoing wires for contact signal transmission. The isolation component is located between two adjacent sets of redundant contact actuation mechanisms and is configured to isolate adjacent sets of redundant contact actuation mechanisms, making the multiple sets of redundant contact actuation mechanisms independent of each other.

[0008] In the above scheme, by setting multiple redundant contact action mechanisms in the nuclear water underwater limit switch and isolating adjacent redundant contact action mechanisms through isolation components, the failure of any one or more of the multiple redundant contact action mechanisms will not affect the normal operation of other contact action mechanisms, thereby improving the reliability of the nuclear water underwater limit switch and meeting the high reliability requirements of the position control of underwater mobile mechanical mechanisms in nuclear power plants.

[0009] In one specific embodiment of this application, the contact actuation mechanism includes a first spring, a first magnet, a second magnet, and a contact system. One end of the first spring is connected to the end face of the main body shell, and the other end of the first spring is connected to the first magnet. The second magnet is connected to the contact system. In the initial state, the first magnet and the second magnet repel each other, and the contact system is disconnected from the output wire. In the detection state where an object is being detected, the first magnet is attracted to the object and moves closer to it, the repulsive force between the first magnet and the second magnet weakens, and the contact system connects to the output wire to output a contact signal.

[0010] In one specific embodiment of this application, the contact system includes a contact bridge body, a contact bridge fixing structure, wiring, an upper contact, a lower contact, and output contacts. The contact bridge fixing structure is configured to fix the contact bridge body. One end of the contact bridge body is connected to a second magnet. In the initial state, the other end of the contact bridge body is in contact with the lower contact. In the detection state, when detecting an object, the other end of the contact bridge body contacts the upper contact and outputs a contact signal through a cable.

[0011] In one specific embodiment of this application, the nuclear underwater limit switch further includes a second spring and a spring fixing base. The second spring is connected to the side of the other end of the contact bridge body. The spring fixing base is mounted on the main body housing or the isolation component, and the spring fixing base is configured to fix the second spring.

[0012] In one specific embodiment of this application, the first magnet component includes a magnet, a magnet rod, and a connector for connecting the magnet and the magnet rod. The end of the magnet facing away from the connector is connected to a first spring.

[0013] In one specific embodiment of this application, the magnet portions of both the first magnet component and the second magnet component are samarium cobalt magnets.

[0014] In one specific embodiment of this application, the external part of the outgoing line is an armored cable.

[0015] In one specific embodiment of this application, the connection position between the connector housing and the main housing, as well as the connection position between the connector housing and the outgoing wire, are both encapsulated with high-temperature and radiation-resistant epoxy resin potting compound.

[0016] In one specific embodiment of this application, the connector housing includes a main body and a plurality of protrusions. A groove is provided between two adjacent protrusions, the groove being configured to receive an isolation member. The protrusions are embedded between the main body housing and the isolation member, or the protrusions are embedded between two adjacent isolation members.

[0017] In one specific embodiment of this application, the number of redundant contact action mechanisms is 2 sets. Attached Figure Description

[0018] Figure 1 The figure shown is a cross-sectional schematic diagram of a nuclear water underwater limit switch provided in an embodiment of this application. Detailed Implementation

[0019] 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 a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application. In the following description, "left" refers to the negative X-axis direction, "right" refers to the positive X-axis direction, "up" refers to the positive Y-axis direction, and "down" refers to the negative Y-axis direction.

[0020] At least one embodiment of this application provides a nuclear water underwater limit switch, see reference. Figure 1The nuclear underwater limit switch 100 includes a main housing 10, a connector housing 20, a lead wire 30, multiple redundant contact actuation mechanisms 40, and an isolation component 50. The main housing 10 has a first opening. The connector housing 20 is embedded within the first opening and has a second opening. The lead wire 30 is sealed at the second opening. The multiple redundant contact actuation mechanisms 40 are located in multiple independent chambers within the cavity enclosed by the main housing 10 and the connector housing 20. Each of the multiple redundant contact actuation mechanisms 40 is configured to be disconnected from the lead wire 30 in the initial state and connected to the lead wire in the detection state to output a contact signal. All cables A in the multiple redundant contact actuation mechanisms 40 are connected to the lead wire 30 for contact signal transmission. The isolation component 50 is located between two adjacent redundant contact actuation mechanisms 40, and the isolation component 50 is configured to isolate the two adjacent redundant contact actuation mechanisms 40 so that the multiple redundant contact actuation mechanisms 40 are independent of each other.

[0021] It should be noted that the contact signal can be further transmitted to the control / display system for display.

[0022] According to the technical solution provided in the embodiments of this application, by setting multiple sets of redundant contact action mechanisms 40 in the nuclear water underwater limit switch 100, and isolating two adjacent sets of redundant contact action mechanisms 40 by means of an isolation component 50, the multiple sets of redundant contact action mechanisms 40 inside the nuclear water underwater limit switch 100 are physically isolated. When one set of contact action mechanisms 40 in the same nuclear water underwater limit switch 100 fails, it will not affect the normal operation of other redundant contact action mechanisms 40. Each set of contact action mechanisms 40 can realize independent functions, realizing single physical redundancy and improving the reliability of the nuclear water underwater limit switch 100. In addition, in this embodiment of the application, by setting all cables A in multiple redundant contact action mechanisms 40 to be connected to the output line 30, contact signals are transmitted through the output line 30, thereby realizing that all cables in multiple redundant contact action mechanisms 40 are centrally connected to the output line 30. This provides a nuclear limit switch with multiple redundant contact action mechanisms 40 and cables integrated, reducing the failure rate that is prone to occur in split structures.

[0023] The nuclear-grade underwater limit switch 100 in this embodiment is mainly used for monitoring and controlling the position of equipment in boric acid water, high radiation dose areas, and high-pressure deep water pools. It can also be used in general locations requiring precise position feedback, meeting the high reliability requirements for position control of underwater mobile machinery in nuclear power plants. The nuclear-grade underwater limit switch 100 can be installed in a fixed location or on mobile machinery.

[0024] In one specific embodiment of this application, reference is made to Figure 1 The number of redundant contact action mechanisms 40 is 2 sets. Thus, by setting the nuclear water underwater limit switch 100 to adopt a dual-redundant structure design, the nuclear water underwater limit switch 100 is a dual-path (i.e., two-output) double-throw (i.e., two sets of limit switches) switch, which improves the reliability of the nuclear water underwater limit switch 100.

[0025] As long as the contact actuation mechanism 40 can be used for position detection and feedback control, the structural design of the contact actuation mechanism 40 is not specifically limited in this application embodiment. The sensing method of the contact actuation mechanism 40 includes, but is not limited to, magnetic induction. The structural design of the contact actuation mechanism 40 will be illustrated below with reference to specific embodiments.

[0026] In one specific embodiment of this application, reference is made to Figure 1 The contact actuation mechanism 40 includes a first spring 41, a first magnet 42, a second magnet 43, and a contact system 44. One end of the first spring 41 is connected to the end face of the main housing 10, and the other end of the first spring 41 is connected to the first magnet 42. The second magnet 43 is connected to the contact system 44. In the initial state, the first magnet 42 and the second magnet 43 repel each other, and the contact system 44 is disconnected from the output line 30. In the detection state, when detecting an object, the first magnet 42 is attracted to the object and moves closer to it. The repulsive force between the first magnet 42 and the second magnet 43 weakens, and the contact system 44 connects to the output line 30 to output a contact signal.

[0027] In this embodiment, the contact actuation mechanism 40 includes a first spring 41, a first magnet 42, a second magnet 43, and a contact system 44, making it a non-contact magnetic limit switch. When the detected object (or target) approaches the contact actuation mechanism 40, the first magnet 42 is attracted by the object and moves in the direction of approaching the object (e.g., to the left). At this time, the first spring 41 is compressed, and the relative position between the first magnet 42 and the second magnet 43 changes, weakening the repulsive force. This causes the contact system 44 to switch states and output a contact signal. When the user removes the detected object, the first spring 41 returns to its initial state, the repulsive force between the first magnet 42 and the second magnet 43 increases, the magnetic force decreases, and the contact system 44 returns to its initial state (i.e., the contact system 44 is disconnected from the output line 30). In this embodiment, the nuclear water underwater limit switch 100 uses magnetic force to actuate the limit switch body structure during use, thereby using the magnetic induction principle to provide position information feedback.

[0028] In one specific embodiment of this application, reference is made to Figure 1The contact system 44 includes a contact bridge body 44a, a contact bridge fixing structure 44b, a circuit 44c, an upper contact 44d, a lower contact 44e, and a lead-out contact 44f. The contact bridge fixing structure 44b is configured to fix the contact bridge body 44a, and one end of the contact bridge body 44a is connected to the second magnet 43. In the initial state, the other end of the contact bridge body 44a is in contact with the lower contact 44e. In the detection state, when detecting the object being detected, the other end of the contact bridge body 44a contacts the upper contact 44d and outputs a contact signal through a cable.

[0029] For example, line 44c is connected to the contact bridge body 44a and remains fixed to it as the contact bridge body 44a moves. Outgoing contact 44f is connected to line 44c and remains connected during switch operation.

[0030] In this embodiment, the contact system 44 includes a contact bridge body 44a, a contact bridge fixing structure 44b, a line 44c, an upper contact 44d, a lower contact 44e, and a lead-out contact 44f, making the switch contacts mechanical and enabling various wiring methods. When the nuclear water underwater limit switch 100 is in a detection state for detecting an object, the first magnet 42 is attracted by the object and moves towards it, weakening the repulsive force exerted by the first magnet 42 on the second magnet 43 on the contact bridge body 44a. One end of the contact bridge body connected to the second magnet 43 moves towards the first magnet 42 (e.g., tilts downwards), while the other end of the contact bridge body 44a disconnects from the lower contact 44e until it contacts the upper contact 44d, thereby enabling the output of a contact signal via a cable. When the user removes the object being detected, the first magnet 42 moves to the right under the action of the first spring 41. The repulsive force exerted by the first magnet 42 on the second magnet 43 on the contact bridge body 44a gradually increases, causing one end of the contact bridge body 44a connected to the second magnet 43 to move away from the first magnet 42 (e.g., tilting upwards). At this time, the other end of the contact bridge body 44a moves in the opposite direction (e.g., tilting downwards), thus disconnecting from the upper contact 44d until contacting the lower contact 44e, thereby restoring the initial state.

[0031] In some embodiments, if the number of redundant contact action mechanisms 40 is 2 sets, then the core underwater limit switch is a double-pole (two pairs of contacts) double-throw switch.

[0032] It should be noted that the contact bridge body 44a is fixed by the contact bridge fixing structure 44b. For the contact actuation mechanism 40 located at the top inside the main body shell 10, the contact bridge fixing structure 44b can be fixed to the inner surface of the main body shell 10. For other contact actuation mechanisms 40, the contact bridge fixing structure 44b can be fixed to the isolation component 50.

[0033] In one specific embodiment of this application, reference is made to Figure 1 The nuclear underwater limit switch 100 also includes a second spring 60 and a spring fixing base 70. The second spring 60 is connected to the side of the other end of the contact bridge body 44a. The spring fixing base 70 is mounted on the main body housing 10 or the isolation component 50, and is configured to fix the second spring 60. Thus, by adding a second spring 60 to the nuclear underwater limit switch 100 and fixing the second spring 60 with the spring fixing base 70, the balance of the contact bridge body 44a is maintained by the second spring 60 and the first magnet 42.

[0034] The first magnet component 42 can be a single integrated structure or a structure consisting of multiple connected magnet components; this embodiment does not specifically limit this. For example, in some embodiments, the first magnet component 42 includes a magnet 42a, a magnet rod 42b, and a connector 42c for connecting the magnet 42a and the magnet rod 42b. The end of the magnet facing away from the connector is connected to a first spring 41. Thus, when the detected object approaches the designated area of ​​the contact actuation mechanism 40, the magnet 42a is attracted by the detected object and moves towards the detected object, causing the connector 42c and the magnet rod 42b to move together. The repulsive force between the magnet rod 42b and the second magnet component 43 is weakened, thereby enabling the contact system 44 to connect to the output line 30 to output a contact signal.

[0035] For example, magnet 42a and connector 42c are bonded together by adhesive. In the initial state, they remain relatively stationary with respect to spring 41. When magnet 42a is attracted during operation, spring 41 deforms, and magnet 42a drives connector 42c to move. When this state ends, it returns to its original position due to the action of spring.

[0036] The second magnet component 43 can be a single integrated structure or a structure consisting of multiple connected magnet components; this application does not specifically limit this. For example, in some embodiments, the second magnet component 43 can be a magnet rod.

[0037] In one specific embodiment of this application, the magnet portions of both the first magnet component 42 and the second magnet component 43 are made of samarium cobalt magnets. Thus, by using samarium cobalt magnets for the magnet portions of both the first magnet component 42 and the second magnet component 43, the stability of the magnetic force of the magnet portions is improved.

[0038] In one specific embodiment of this application, the external part of the outgoing line 30 is an armored cable. Thus, by setting the external part of the outgoing line 30 to an armored cable, all cables of the multiple redundant contact action mechanisms 40 can transmit contact signals through the outgoing line 30. By designing the rear wiring section and the switch body as an integrated structure, the failure rate that is prone to occur in separate structures is reduced.

[0039] In one specific embodiment of this application, the connection points between the connector housing 20 and the main housing 10, as well as the connection points between the connector housing 20 and the outgoing wire 30, are encapsulated with high-temperature and radiation-resistant epoxy resin potting compound. Thus, by using high-temperature and radiation-resistant epoxy resin potting compound, the sealing performance of the nuclear water underwater limit switch 100 is enhanced, improving its performance in nuclear water underwater environments and its adaptability to water quality.

[0040] For example, the high-temperature and radiation-resistant epoxy resin potting compound can be a high-temperature resistant A / B compound. The nuclear water underwater limit switch 100 potted with the high-temperature resistant A / B compound can work stably at 180°C and is suitable for deep-water underwater environments.

[0041] In some embodiments, direct wiring can be used outside the outlet wire 30, with all cables (or power cables) clamped by metal sealing gaskets and potted with high-temperature and radiation-resistant epoxy resin potting compound.

[0042] In one specific embodiment of this application, the connector housing 20 includes a main body 21 and a plurality of protrusions 22 connected to the main body 21. A groove is formed between two adjacent protrusions, configured to accommodate an isolation member 50. The protrusions 22 are embedded between the main body housing 10 and the isolation member 50, or between two adjacent isolation members 50. Thus, by providing a groove on the connector housing 20 to accommodate the isolation member 50, it is more advantageous to ensure that multiple redundant contact actuation mechanisms 40 are independent of each other. Furthermore, by including the main body 21 and the plurality of protrusions 22 in the connector housing 20, the structural connection between the connector housing 20, the main body housing 10, and the isolation member 50 is tighter, which is more conducive to improving the sealing performance of the nuclear water underwater limit switch 100.

[0043] It should 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 they contradict each other.

[0044] The above are merely preferred embodiments of this application and are 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 nuclear water underwater limit switch, characterized in that, include: The main body shell has a first opening; The connector housing is embedded in the first opening and has a second opening; Connect the outgoing wire and seal it at the second opening; Multiple redundant contact actuation mechanisms are located in multiple independent chambers within the cavity enclosed by the main body shell and the connector shell. Each mechanism is configured to be disconnected from the output line in the initial state, and connected to the output line in the detection state (detecting an object) to output a contact signal. All cables in the multiple redundant contact actuation mechanisms are connected to the output line for contact signal transmission. An isolation component is located between two adjacent redundant contact actuation mechanisms and is configured to isolate the two adjacent redundant contact actuation mechanisms so that the multiple redundant contact actuation mechanisms are independent of each other. The contact actuation mechanism includes a first spring, a first magnet, a second magnet, and a contact system. One end of the first spring is connected to the end face of the main body shell, and the other end of the first spring is connected to the first magnet. The second magnet is connected to the contact system. In the initial state, the first magnet and the second magnet repel each other, and the contact system is disconnected from the output line. In the detection state where the object being detected is being detected, the first magnet is attracted to the object being detected and moves closer to it. The repulsive force between the first magnet and the second magnet weakens, and the contact system is connected to the output line to output a contact signal. The contact system includes a contact bridge body, a contact bridge fixing structure, wiring, an upper contact, a lower contact, and output contacts. The contact bridge fixing structure is configured to fix the contact bridge body. One end of the contact bridge body is connected to the second magnet component. In the initial state, the other end of the contact bridge body is in contact with the lower contact. In the detection state when detecting the object being detected, the other end of the contact bridge body contacts the upper contact and outputs a contact signal through a cable. The second spring is connected to the side of the other end of the contact bridge body. A spring fixing base is mounted on the main body shell or the isolation component and is configured to fix the second spring.

2. The nuclear water underwater limit switch according to claim 1, characterized in that, Also includes: The first magnet component includes a magnet, a magnet rod, and a connector for connecting the magnet and the magnet rod, wherein the end of the magnet facing away from the connector is connected to the first spring.

3. The nuclear water underwater limit switch according to claim 1, characterized in that, Both the first magnet component and the second magnet component use samarium cobalt magnets for their magnet portions.

4. The nuclear water underwater limit switch according to any one of claims 1 to 3, characterized in that, The external part of the outgoing line is an armored cable.

5. The nuclear water underwater limit switch according to any one of claims 1 to 3, characterized in that, The connection points between the connector housing and the main housing, as well as the connection points between the connector housing and the outgoing wire, are all encapsulated with high-temperature and radiation-resistant epoxy resin potting compound.

6. The nuclear water underwater limit switch according to any one of claims 1 to 3, characterized in that, The connector housing includes a main body and a plurality of protrusions, with a groove between two adjacent protrusions. The groove is configured to accommodate the isolation component. The protrusions are embedded between the main body housing and the isolation component, or the protrusions are embedded between two adjacent isolation components.

7. The nuclear water underwater limit switch according to any one of claims 1 to 3, characterized in that, The number of redundant contact action mechanisms is 2 sets.

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