JP2014118995A - Valve opening and closing device and valve opening and closing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve opening and closing device and a valve opening and closing method enabling the valve opening and closing operation to be carried out from a remote safe location when a major operating source is lost.SOLUTION: A valve main body 1 is normally operated by a motor 60 (major torque inputting means) driven by an AC power supply (a major operating source). When the AC power supply is lost and the motor 60 does not operate, if a DC impact driver 15 (spare torque inputting means) driven by a DC power supply (a spare operating source) is operated, torque is transmitted to an actuator 2 through flexible shafts 4a, 4b. Input of torque is automatically changed over from the motor 60 to the DC impact driver 15 by an automatic clutch releasing mechanism arranged inside the actuator 2 to enable operation of the valve main body 1 from the outside of a nuclear reactor building.

Description

  The present invention relates to a valve opening / closing device and a valve opening / closing method for opening and closing a valve from a remote location.

  2. Description of the Related Art Conventionally, a valve opening / closing device is configured so that it can be opened and closed by a spare operation source such as human power when a main operation source such as an AC power source is lost. For example, in the actuator described in Patent Document 1, the shaft 17 is normally rotated by the electric motor 21, but when the electric motor 21 is inoperable, it is rotated by the handwheel 20 for manual operation (patent). (Literature 1 paragraphs 0023 and 0024, FIG. 2 etc.).

Japanese translation of PCT publication No. 2002-512353

  For example, there may be a case where a person cannot enter a place where a handle for manual operation is installed due to a high radiation atmosphere, such as when an accident occurs at a nuclear power plant. Further, even if manual operation can be performed from a remote place using a flexible shaft or the like, there are cases where the input switching lever or the like is in the vicinity of the valve and cannot be operated in the event of an accident. For this reason, there has been a problem that operations to be performed in an emergency such as venting of a containment vessel cannot be performed. Therefore, an object of the present invention is to provide a valve opening / closing device and a valve opening / closing method capable of opening and closing a valve from a remote and safe place when a main operation source is lost.

  The present invention that solves the above problems includes an actuator that opens and closes a valve, main torque input means that is driven by a main operation source and inputs torque to the actuator, and a preliminary operation source that can be used when the main operation source is lost. And a pre-torque input means that inputs a torque to the actuator via a flexible shaft, and the actuator has an auto-declutch mechanism that automatically switches the input between the main torque input means and the pre-torque input means. It is characterized by.

  When the pre-torque input means driven by the pre-operation source is activated when the main operation source is lost and the main torque input means does not operate, torque is transmitted to the actuator via the flexible shaft. Torque input is automatically switched from the main torque input means to the preliminary torque input means by an automatic clutch mechanism provided inside the actuator. Therefore, when the main operating source is lost, the valve can be opened and closed from a remote and safe place.

1 is an overall view of a valve opening / closing device. 1 is an overall view of a valve opening / closing device. It is detail drawing of the wall penetration part of a reactor building. It is a figure explaining operation | movement of an auto-declutch mechanism. It is a figure explaining operation | movement of a clutch fork. It is a structural diagram of a flexible shaft.

  Hereinafter, a valve opening and closing apparatus according to an embodiment of the present invention will be described in detail based on the embodiments shown in the drawings. Here, an example will be described in which the valve opening and closing device is installed inside and outside the nuclear reactor building.

  FIG. 1 is an overall view of a valve opening / closing device 100 of the present invention. The valve opening / closing device 100 penetrates the actuator 2 that opens and closes the valve body 1 installed in the reactor building, the two flexible shafts 4a and 4b, the motor 60 that inputs torque to the actuator 2, and the reactor building wall 14. A through shaft 12, an opening meter 11 installed outside the reactor building, and a direct current impact driver 15.

  The actuator 2 receives torque from a motor 60 (main torque input means) that is normally driven by an AC power supply (an example of a main operation source). Torque is transmitted to the valve body 1 via the drive sleeve 51 to open and close the valve. A DC impact driver 15 is connected to the other input end of the actuator 2 through a coupling 3, a flexible shaft 4 a, a speed reducer 5, a flexible shaft 4 b, and a through shaft 12. The actuator 2 includes an auto-declutch mechanism that automatically switches between the two torque input means.

  A speed reducer 5 that transmits the rotation of the flexible shaft 4b to the flexible shaft 4a while reducing the number of rotations is provided at a connection portion of the flexible shafts 4a and 4b. The reduction gear 5 is fixed to a reduction gear frame 6 fixed to a strong structure such as a floor of a reactor building by bolting or the like. The flexible shafts 4 a and 4 b are fixed by a support 8. The supports 8 are arranged at intervals of about 3 m and are constituted by clamps bolted to the floor of the reactor building, for example.

  As shown in FIG. 3, a through hole 16 is formed in the reactor building wall 14, an outer tube 13 is disposed through the through hole 16, and a through shaft 12 is disposed through the outer tube 13. ing. Both ends of the through shaft 12 are supported by bearings of a bearing 19 of the inner bearing portion 9 and a bearing 20 of the outer bearing portion 10 fixed to the reactor building wall 14 by bolts or the like. A blocking lid 18 is provided at the end of the through hole 16 on the reactor building outdoor side, and the through hole 16 has a ground structure in which air inside the reactor building does not leak out to the reactor building outdoor.

  A flexible shaft 4b is connected to the end of the penetration shaft 12 inside the reactor building via a connector 7, and a direct current that operates with an opening meter 11 and a DC power source (an example of a preliminary operation source) is connected to the end outside the reactor building. Impact drivers 15 (an example of preliminary torque input means) are connected to each other.

  The opening degree meter 11 displays the opening degree of the valve body 1 based on the rotation of the flexible shaft 4b. In the case of a severe accident in which the main operating source is lost although the accuracy is inferior, It is provided because it is assumed that the original opening meter (not shown) provided does not operate or that a person cannot enter a position where it can be seen even if it operates. Therefore, the opening meter 11 is provided in the vicinity of the preliminary torque input means.

  The DC impact driver 15 is a tool that includes a storage battery and is operated by a DC current, and is usually used to tighten a bolt.

  As the preliminary operation source, a source other than the DC power source can be used. For example, a handle or crank that is rotated manually can be connected to the penetrating shaft 12. Further, an air motor that operates with a gas pressure such as compressed air or compressed nitrogen stored in a cylinder may be connected to the through shaft 12. Compressed nitrogen is preferred when it is desired to use an inert gas.

  When the reduction gear base 6 cannot be provided between the actuator 2 and the reactor building wall 14, the reduction gear 5 is provided at the connection portion between the actuator 2 and the flexible shaft 4c as shown in FIG. Also good. A plate-like speed reducer base 6a is provided so as to be sandwiched between the upper part of the valve body 1 and the lower part of the actuator 2, and the speed reducer 5 is fixed thereon via a spacer plate 6b for height adjustment. By doing in this way, the valve body 1, the actuator 2, the coupling 3, and the speed reducer 5 come to vibrate synchronously during an earthquake, and the seismic force acting on the coupling 3 is reduced. The configuration shown in FIG. 2 is the same as that shown in FIG. 1 except that the position of the speed reducer 5 and its fixing method and the number of flexible shafts is one. Is omitted.

  If there is no wall between the valve body 1 and the DC impact driver 15 in the configuration of FIG. 1 or FIG. 2, the flexible shaft 4b or the flexible shaft 4c and the opening meter 11 may be directly connected.

  4 and 5 are diagrams for explaining the auto-declutch mechanism inside the actuator 2. A worm shaft clutch gear 41, a tripper pin 44, a worm shaft clutch 45, a fork return spring 46, a clutch pinion 42, and a worm 48 are attached to the worm shaft 43. A gear 47 is attached to the shaft 50 to which torque is input from the DC impact driver 15 via the flexible shafts 4a and 4b (4c in the configuration of FIG. 2).

  The worm shaft clutch gear 41 and the clutch pinion 42 are structured to idle with respect to the worm shaft 43. On the other hand, the worm shaft clutch 45 rotates together with the worm shaft 43 because it is fitted with the spline. Therefore, the worm shaft clutch gear 41 and the clutch pinion 42 rotate together with the worm shaft 43 by engaging with the worm shaft clutch 45. The clutch fork 31 is attached by two flippers 32 and 33 so as to hold and release the worm shaft 43 at a position where the tripper pin 44 is attached.

  The auto-declutch mechanism operates as follows when the valve body 1 is normally opened and closed by the motor 60. The worm shaft clutch 45 and the worm shaft clutch gear 41 are engaged with each other. The rotation from the motor 60 is transmitted to the worm shaft clutch 45 and the worm shaft 43 via the motor pinion 61 and the worm shaft clutch gear 41. The rotation of the worm shaft 43 is transmitted to the drive sleeve 51 via a worm 48 and a worm gear (not shown) that meshes with the worm 48.

  The auto-declutch mechanism operates as follows when the AC power source, which is the main operation source, is lost and the motor 60 does not operate. The rotation of the DC impact driver 15 is transmitted to the shaft 50 via the through shaft 12, the flexible shaft 4b, the speed reducer 5, and the flexible shaft 4a (the through shaft 12, the flexible shaft 4c, and the speed reducer 5 in the configuration of FIG. 2). The gear 47 rotates. A roller 49 provided on the gear 47 pushes the flipper 34 of the clutch fork 31. When the flipper 34 is pushed, the clutch fork 31 operates to move the worm shaft clutch 45 in the direction of arrow B in FIG. The worm shaft clutch 45 is disengaged from the worm shaft clutch gear 41 and is engaged with the clutch pinion 42. The worm shaft clutch 45 and the clutch fork 31 are held in this state by the trippers 32 and 33 (FIG. 5B). The rotation of the shaft 50 is transmitted to the worm shaft clutch 45 and the worm shaft 43 through the gear 47 and the clutch pinion 42. The rotation of the worm shaft 43 is transmitted to the drive sleeve 51 in the same manner as normal.

  The auto-declutch mechanism operates as follows when the AC power is restored and the motor 60 returns to the operation. When the motor 60 is activated, the rotation of the motor pinion 61 is transmitted to the worm shaft clutch gear 41. When the worm shaft clutch gear 41 rotates, the tripper pin 44 widens the distance between the trippers 32 and 33 and releases the hold of the clutch fork 31 (FIG. 5A). When the holding of the clutch fork 31 is released, the worm shaft clutch 45 moves in the direction of arrow A in FIG. The worm shaft clutch 45 is disengaged from the clutch pinion 42 and is engaged with the worm shaft clutch gear 41, and the rotation of the worm shaft 43 is transmitted to the drive sleeve 50 in the same manner as in the above-described normal operation.

  When the AC power source is lost due to the operation of the automatic clutch mechanism and the motor 60 stops operating, the DC impact driver 15 can be operated and the torque input means can be operated without operating the switching lever or the like. Can be switched. Therefore, the operator can safely open and close the valve body 1 from the reactor building remote from the valve body 1.

  FIG. 6 is a schematic diagram illustrating the structure of the flexible shafts 4a, 4b, and 4c (hereinafter collectively referred to as the flexible shaft 4). The flexible shaft 4 is roughly composed of a shaft body 70 and a protective tube 80. The shaft main body 70 is a member that transmits torque, and thin piano wires 72a, 72b, 72c, and 72d are wound around a plurality of layers spirally in opposite directions around a central core member 71. The protective tube 80 is a tubular member for preventing a decrease in transmission torque and a decrease in breaking torque due to twisting and undulation generated in the shaft body 70, and a liner 81 and a helical tube 82 in which a flat steel material is wound spirally from the center side. A four-layer structure of a steel wire braid 83 woven from a steel wire and an outer tube 84 made of synthetic rubber such as nitrile rubber or synthetic resin.

  With such a configuration, the flexible shaft 4 can be bent and arranged as long as it has a predetermined bending radius or more, and can transmit torque with high efficiency.

DESCRIPTION OF SYMBOLS 1 Valve body 2 Actuator 3 Coupling 4a, 4b, 4c Flexible shaft 5 Reduction gear 6 Reduction gear mount 6a Reduction gear base 6b Spacer plate 7 Joint 8 Support 9 Inner bearing portion 10 Outer bearing portion 11 Opening meter 12 Through shaft 13 Outer tube 14 Reactor building wall 15 DC impact driver 16 Through hole 18 Closure lid 19, 20 Bearing 31 Clutch fork 32, 33 Tripper 34 Flipper 41 Worm shaft clutch gear 42 Clutch pinion 43 Warm shaft 44 Tripper pin 45 Warm shaft clutch 46 Fork Return spring 47 Gear 48 Worm 49 Roller 50 Shaft 51 Drive sleeve 60 Motor 61 Motor pinion 70 Shaft body 71 Core materials 72a, 72b, 7 c, 72d piano wire 80 protective tube 81 liner 82 spiral tube 83 steel wire braid 84 outer tube 100 valve control

Claims (8)

An actuator for opening and closing the valve;
Main torque input means which is driven by a main operation source and inputs torque to the actuator;
A preliminary torque input means that is driven by an available preliminary operation source when the main operation source is lost and inputs torque to the actuator via a flexible shaft;
The actuator is provided with an auto-declutch mechanism that automatically switches input between main torque input means and preliminary torque input means.   The valve, the actuator, and the flexible shaft are installed inside the building, the preliminary torque input means is installed outside the building, and the flexible shaft and the preliminary torque input means are connected by a through shaft that penetrates the wall of the building. The valve opening and closing device according to claim 1, wherein the through-hole to be arranged has a ground structure that does not allow air inside the building to leak into the outdoor portion of the building.   The valve opening / closing device according to claim 1 or 2, wherein a speed reducer is provided in the middle of the flexible shaft.   The valve opening / closing apparatus according to claim 1, wherein a reduction gear is provided at a connection portion between the flexible shaft and the actuator.   The valve opening / closing apparatus according to any one of claims 1 to 4, wherein the main operation source is an AC power source, the preliminary operation source is a DC power source, and the preliminary torque input means is an impact driver.   5. The valve opening / closing apparatus according to claim 1, wherein the main operation source is an AC power source, the preliminary operation source is human power, and the preliminary torque input means is a handle or a crank.   5. The valve opening / closing apparatus according to claim 1, wherein the main operation source is an AC power source, the preliminary operation source is a gas pressure, and the preliminary torque input means is an air motor.   Torque input to the actuator that opens and closes the valve is performed by a main torque input means driven by a main operation source, and a spare shaft driven by a spare operation source that can be used when the main operation source is lost. A valve opening / closing method characterized in that the valve is automatically switched with a torque input means by an automatic clutch mechanism provided in the actuator.

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