A pneumatic locking device for a control rod drive mechanism of a pool-type cryogenic reactor

Abstract

The present invention relates to a pneumatic locking device for a control rod drive mechanism of a pool-type low-temperature reactor, comprising a bellows, a connecting rod mechanism, a hook assembly and an end head; the two ends of the bellows are respectively connected to the connecting rod mechanism and the hook assembly; the change in the length of the bellows causes the connecting rod mechanism to act on the hook assembly so that the hook of the hook assembly grabs / releases the end head. The beneficial effects of the present invention are as follows: 1. The hook assembly is driven by the bellows to grab the end head, thereby achieving the purpose of providing a large grabbing force with a small gas pressure, preventing the control rod assembly under the end head from falling off during vibration, and working reliably; 2. The cylinder body and the control rod assembly are automatically aligned and connected through the guide cylinder; 3. By setting the reset spring, it is ensured that in the event of power failure, it can be quickly disengaged to release the control rod assembly; 4. The air supply component is easy to seal underwater.

Description

Technical Field

[0001] The invention relates to the field of nuclear technology, and in particular to a pneumatic locking device for a control rod driving mechanism of a pool-type low-temperature reactor. Background Art

[0002] The control rod drive mechanism is an important equipment to ensure the safety of the reactor. The performance of the control rod drive mechanism directly affects the safety of the nuclear reactor. The locking device is a key component of the control rod drive mechanism of the pool-type low-temperature reactor. It is related to the safety of the nuclear reactor and the refueling process.

[0003] Pool-type heating reactors have been used in China, but they have low power, a small number of control rod drive mechanisms, and a small weight of control rod assemblies, so the required lifting force is also small. If the lifting force is to be increased, the volume of the electromagnet device must be increased. The reactor core has the characteristics of compact layout, and the space left for the control rod drive mechanism is generally limited. When designing the electromagnet device, the size restrictions must be considered, and the operation must be reliable. In addition to the electromagnet device, there is no other type of related technology in the prior art that can meet the above requirements.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] In view of the defects existing in the prior art, the purpose of the present invention is to provide a pneumatic locking device for a control rod drive mechanism of a pool-type low-temperature reactor, which can provide a large gripping force with a small gas pressure to grip the end.

[0006] The technical solution of the present invention is as follows:

[0007] A pneumatic locking device for a control rod drive mechanism of a pool-type low-temperature reactor comprises a bellows, a connecting rod mechanism, a hook assembly and an end head; the two ends of the bellows are respectively connected to the connecting rod mechanism and the hook assembly; the length of the bellows changes so that the connecting rod mechanism acts on the hook assembly so that the hook of the hook assembly grabs / releases the end head.

[0008] Furthermore, the above-mentioned pool-type low-temperature reactor control rod drive mechanism uses a pneumatic locking device, and the claw assembly includes a cylinder and a claw; the claw is installed on the cylinder through a pin shaft; the claw is also connected to the connecting rod mechanism and rotates around the pin shaft under the drive of the connecting rod mechanism to grasp / release the end head.

[0009] Furthermore, the above-mentioned pool-type low-temperature reactor control rod drive mechanism uses a pneumatic locking device, and the connecting rod mechanism includes a central connecting rod and a first connecting rod; the two ends of the first connecting rod are respectively hinged to the ends of the central connecting rod and the hook claw; the central connecting rod is connected to the bellows; and a centering hole for the central connecting rod to pass through is provided on the cylinder.

[0010] Furthermore, in the above-mentioned pool-type low-temperature reactor control rod drive mechanism using a pneumatic locking device, the hook assembly also includes an upper cover; the upper cover is fixedly connected to the cylinder; and the bellows is connected to the upper cover.

[0011] Furthermore, the above-mentioned pneumatic locking device for the control rod drive mechanism of the pool-type low-temperature reactor also includes an outer cylinder wall; the cylinder body is arranged in the outer cylinder wall and can move along the outer cylinder wall; the size of the cylinder body matches the size of the outer cylinder wall.

[0012] Furthermore, the control rod drive mechanism of the above-mentioned pool-type low-temperature reactor uses a pneumatic locking device, and the upper cover is also provided with rollers that are conducive to the movement of the hook assembly; the number of the rollers is 2-4, and they are evenly arranged around the cylinder.

[0013] Furthermore, the control rod drive mechanism of the above-mentioned pool-type low-temperature reactor uses a pneumatic locking device, and a hole connecting the inside and outside of the cylinder is opened on the cylinder.

[0014] Furthermore, in the above-mentioned pneumatic locking device for the control rod drive mechanism of the pool-type low-temperature reactor, a return spring is provided between the hook assembly and the connecting rod mechanism.

[0015] Furthermore, in the above-mentioned pneumatic locking device for the control rod drive mechanism of the pool-type low-temperature reactor, the number of the return springs is 1-4, and they are arranged on the central axis or the pitch circle of the cylinder.

[0016] Furthermore, the control rod drive mechanism of the above-mentioned pool-type low-temperature reactor uses a pneumatic locking device, and the number of the hooks is 2-3, which are evenly arranged on the cylinder.

[0017] Furthermore, the pneumatic locking device for the control rod drive mechanism of the above-mentioned pool-type low-temperature reactor is provided with a stop step on the end head that cooperates with the hook claw assembly.

[0018] The beneficial effects of the present invention are as follows:

[0019] 1. The claw assembly is driven by the bellows to grab the end, so as to achieve the purpose of providing a large grabbing force with a small gas pressure, preventing the control rod assembly under the end from falling off during vibration, and the operation is reliable;

[0020] 2. The cylinder and control rod assembly are automatically aligned and connected through the guide cylinder;

[0021] 3. By setting the reset spring, it is ensured that the control rod assembly can be quickly disengaged and released in the event of power failure.

[0022] 4. The air supply components are easy to seal underwater. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the pneumatic locking device for the control rod drive mechanism of a pool-type low-temperature reactor of the present invention (grasping state).

[0024] Figure 2 It is a structural schematic diagram of the pneumatic locking device for the control rod drive mechanism of a pool-type low-temperature reactor of the present invention (open state).

[0025] Figure 3 It is a schematic diagram of the distribution of the rollers of the present invention.

[0026] Figure 4 It is a schematic diagram of the distribution of the hook claws of the present invention.

[0027] Figure 5 It is a distribution diagram of the return spring of the present invention.

[0028] In the above drawings, 1, outer cylinder wall; 2, upper cover; 3, roller; 4, return spring; 5, first connecting rod; 6, hook claw; 7, end; 8, cylinder body; 9, center connecting rod; 10, bellows; 11, connecting screw; 12, air pipe; 13, pin; 14, pin. DETAILED DESCRIPTION

[0029] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0030] like Figure 1 and Figure 2 As shown, the present invention provides a pneumatic locking device for a control rod drive mechanism of a pool-type low-temperature reactor, comprising a bellows 10, a connecting rod mechanism, a hook assembly and an end 7; the two ends of the bellows 10 are respectively connected to the connecting rod mechanism and the hook assembly; the length of the bellows 10 changes so that the connecting rod mechanism acts on the hook assembly so that the hook 6 of the hook assembly grabs / releases the end 7. The end 7 is provided with a stop step that cooperates with the hook assembly.

[0031] like Figure 1 and Figure 4As shown, the hook assembly includes a hook 6, a cylinder 8 and an upper cover 2; the hook 6 is installed on the cylinder 8 through a pin 13; the hook 6 is also connected to the connecting rod mechanism and rotates around the pin 13 under the drive of the connecting rod mechanism to grab / release the end 7. The connecting rod mechanism includes a central connecting rod 9 and a first connecting rod 5; the two ends of the first connecting rod 5 are respectively hinged to the ends of the central connecting rod 9 and the hook 6; the two ends of the bellows 10 are respectively connected to the upper cover 2 and the central connecting rod 9, and a closed chamber is formed inside the bellows 10. The cylinder 8 is provided with a centering hole (i.e., a guide hole or groove) for the central connecting rod 9 to pass through; in this way, the central connecting rod 9 can only move axially along the guide hole or groove, and the guide hole or groove has a limit step to limit the stroke of the central connecting rod 9. The upper cover 2 is fixedly connected to the cylinder 8; the bellows 10 is connected to the upper cover 2. In this embodiment, the upper cover 2 is fixedly connected to the cylinder 8 by connecting screws 11, and the air pipe 12 of the bellows 10 passes through the upper cover 2 and extends out from the top.

[0032] The pneumatic locking device for the control rod drive mechanism of the pool-type low-temperature reactor of this embodiment also includes an outer cylinder wall 1; the hook assembly is arranged inside the outer cylinder wall 1 and can move along the outer cylinder wall 1; the cylinder body 8 is provided with a centering hole for the push rod 6 to pass through; the size of the cylinder body 8 matches the size of the outer cylinder wall 1. The upper cover 2 is also provided with rollers 3 that facilitate the movement of the cylinder body 8. The number of the rollers is 2-4, which are evenly arranged around the upper cover 2. Figure 3 As shown, the roller 3 is installed through the pin 14. When the pneumatic locking device of the driving mechanism is installed into the outer cylinder wall 1 from the top, the roller 3 slides along the inner wall of the outer cylinder wall 1, and the end head 7 connected to the control rod assembly is automatically centered. When the pneumatic locking device and the stop step of the end head 7 coincide, the grabbing function can be realized through the pneumatic control of the bellows 10. The stop step allows the pneumatic locking device and the end head 7 to fit in place, preventing the claw 6 from failing to grab the end head 7.

[0033] like Figure 5 As shown, a return spring 4 is arranged between the central connecting rod 9 and the cylinder 8. The number of the return springs 4 is 1-4, and they are arranged on the central axis or the pitch circle of the cylinder 8.

[0034] When in use, the pneumatic lock takes in air from the air pipe 12, the pressure in the bellows 10 increases, pushing the center link 9 to move, and the return spring 4 is compressed, the center link 9 drives the link to move, so that the hook 6 rotates and closes to grab the end 7, thereby driving the control rod assembly to move up and down or maintain a fixed position. The pneumatic lock exhausts air from the air pipe 12, the pressure in the bellows 10 decreases, the center link 9 is pushed back by the return spring 4, and the hook 6 opens to release the control rod assembly. The schematic diagram of the pneumatic lock hook 6 in the open state is shown in FIG. Figure 2As shown. When the gas pressure changes, the movement of the center connecting rod 9 will cause the volume of the chamber between the cylinder 8 and the bellows 10 to change. A hole is opened on the cylinder 8 to reduce the damping of the liquid flow when the length of the bellows changes, thereby reducing the resistance to the movement of the center connecting rod 9. In this embodiment, the hook 6 can be opened without external force intervention in the case of power failure, realizing the rapid rod drop function of the control rod drive mechanism. The spring has high working reliability, thereby also improving the reliability of the rapid rod drop function of the control rod drive mechanism.

[0035] The working environment medium of the electromagnet device is water, and the electrical component is only the electromagnetic coil. The coil is sealed in the closed space of the electromagnetic component, and only the external wire of the electromagnetic coil needs to be led out, which reduces the work of underwater sealing of the coil.

[0036] In this embodiment, the hook assembly is driven by the bellows 10 to grab the end head 7, so as to achieve the purpose of providing a large grabbing force with a small electromagnetic force, preventing the control rod assembly under the end head 7 from falling off during vibration, and the operation is reliable; the electromagnet device can be automatically connected to the control rod assembly in a centering manner through the guide cylinder; and the reset spring 4 is set to ensure that the control rod assembly can be quickly disengaged and released in the event of power failure.

[0037] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A pneumatic locking device for a control rod drive mechanism of a pool-type low-temperature reactor, characterized in that: The invention comprises a bellows (10), a connecting rod mechanism, a hook assembly and an end (7); the two ends of the bellows (10) are respectively connected to the connecting rod mechanism and the hook assembly; the hook assembly comprises a cylinder (8) and a hook (6); the hook (6) is mounted on the cylinder (8) via a pin (13); the connecting rod mechanism comprises a central connecting rod (9) and a first connecting rod (5); the two ends of the first connecting rod (5) are respectively hinged to the ends of the central connecting rod (9) and the hook (6); the central connecting rod (9) is connected to the bellows (10); a centering hole for the central connecting rod (9) to pass through is provided on the cylinder (8); a return spring (4) is provided between the hook claw assembly and the connecting rod mechanism; the hook claw (6) is also connected to the connecting rod mechanism; the change in the length of the bellows (10) causes the connecting rod mechanism to act on the hook claw assembly so that the hook claw (6) of the hook claw assembly rotates around the pin shaft (13) under the drive of the connecting rod mechanism to grasp / release the end head (7).

2. The pneumatic locking device for the control rod drive mechanism of a pool-type low-temperature reactor according to claim 1, characterized in that: The hook assembly further comprises an upper cover (2); the upper cover (2) is fixedly connected to the cylinder (8); and the bellows (10) is connected to the upper cover (2).

3. The pneumatic locking device for the control rod drive mechanism of a pool-type low-temperature reactor according to claim 2, characterized in that: It also comprises an outer cylinder wall (1); the cylinder body (8) is arranged inside the outer cylinder wall (1) and is movable along the outer cylinder wall (1); and the size of the cylinder body (8) matches the size of the outer cylinder wall (1).

4. The pneumatic locking device for the control rod drive mechanism of a pool-type low-temperature reactor according to claim 3, characterized in that: The upper cover (2) is also provided with rollers (3) that facilitate the movement of the hook claw assembly. The number of the rollers is 2-4 and they are evenly arranged around the cylinder (8).

5. The pneumatic locking device for a control rod drive mechanism of a pool-type low-temperature reactor according to any one of claims 1 to 4, characterized in that: The cylinder (8) is provided with a hole communicating with the inside and outside of the cylinder (8).

6. The pneumatic locking device for the control rod drive mechanism of a pool-type low-temperature reactor according to claim 1, characterized in that: The number of the return springs (4) is 1 to 4, and they are arranged on the central axis or the pitch circle of the cylinder (8).

7. The pneumatic locking device for the control rod drive mechanism of a pool-type low-temperature reactor according to claim 1, characterized in that: The hook assembly has 2-3 hooks.

8. The pneumatic locking device for a control rod drive mechanism of a pool-type low-temperature reactor according to any one of claims 1 to 4, characterized in that: The end head (7) is provided with a stop step which cooperates with the hook claw assembly.

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