JP2006097706A - Emergency shutoff valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To operate an emergency shutoff valve by corresponding to both of detection of excessive flow velocity and a signal from a seismometer. <P>SOLUTION: A rotary valve for attaching a valve element 2 to a valve shaft 5 inside a valve box 3 is provided in a pipe passage P, and an arm 7 with a weight 6 is attached to the valve shaft 5 so as to turn in the vertical direction. The arm 7 is locked by a locking lever 8 capable of swinging in the vertical direction to maintain a valve opening condition by preventing descent of the weight 6. An orifice 10 is provided on the upstream side of the rotary valve to connect pressure introducing pipes 11, 12 with each pipe passage P in front and rear of it. A differential pressure cylinder 20 operating based on its differential pressure is provided to swing the locking lever 8 by advance and retraction of a piston rod 23 of the cylinder 20 and release the locking. A pressure release mechanism 15 by an electromagnetic valve is provided in the pressure introducing pipe 12 on the downstream side of the orifice 10 to release pressure in the pipe by a signal from the seismometer 19. In this differential pressure emergency shutoff valve, it can correspond to even an electric signal from the seismometer 19 by constituting the valve in this way. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an emergency shut-off valve that is installed in piping of waterworks, hydroelectric power stations, etc. and automatically or manually shuts off the pipeline in an emergency such as a large earthquake.

  As a conventional emergency shut-off valve, for example, an emergency shut-off valve described in Patent Document 1 will be described with reference to FIG. 2 which is an explanatory view of the present invention. The valve box 3 of the rotary valve to which the valve body 2 is attached is provided so as to be interposed in the pipe line P, and an arm 7 that rotates around the shaft together with the valve shaft 5 is attached to one end of the valve shaft 5; A weight 6 is provided at the tip of the arm 7. A long locking lever 8 is provided on the frame 4 fixed to the valve box 3, and the locking lever 8 is supported by a support pin 9 in the middle in the length direction so as to be swingable in the vertical direction. A locking hole 8 a into which a pin 7 a provided on the arm 7 is fitted is formed on the lower surface of one end of the locking lever 8.

  As shown in FIG. 2, this emergency shut-off valve locks the locking hole 8a of the locking lever 8 to the pin 7a of the arm 7 with the arm 7 facing upward, as shown in FIG. By locking, the weight 6 is prevented from descending and the valve open state is maintained.

An orifice 10 is provided in the pipe line, and a differential pressure cylinder 20 that is movable by a pressure difference before and after the orifice 10 is connected to the other end of the locking lever 8. When the differential pressure before and after the orifice 10 increases due to the increase in the flow rate of the pipe line, and the differential pressure exceeds a predetermined value, the differential pressure cylinder 20 is actuated to swing the locking lever 8 and the arm 7 Release the lock. When the lock is released, the arm 7 is rotated by its own weight, and the valve shaft 5 is rotated to close the valve P to block the flow of the pipe P. At this time, as shown in FIG. 1, the damper 25 is attached to the attachment member 4a of the frame 4 via the pin 25c, and the tip of the rod 25a of the damper 25 is attached to the attachment member 7b of the arm 7 via the pin 25b. It is connected to the. For this reason, the weight 6 falls gently, and the valve body 2 is gently closed.
JP 2002-71039 A

Note that the emergency shut-off valve described in Patent Document 2 has a locking lever locked to the arm to prevent the arm from rotating, and when the solenoid is actuated by a signal from a seismometer, the locking lever Is rocked to release the arm. Furthermore, the emergency shut-off valve described in Patent Document 3 is provided with a cylinder that maintains the locking portion in the locked state by the fluid pressure in the pressure chamber. When the fluid pressure becomes a certain value or less, the piston rod of the cylinder is operated by the force of the spring to release the lock.
JP-A-9-242918 Japanese Patent Laid-Open No. 9-100977

  However, the emergency shut-off valve described in the above-mentioned Patent Document 1 is intended to detect an excessive flow velocity in the pipeline and automatically shut off the pipeline mechanically. It could not be applied to the purpose of electrically blocking the pipeline by a signal. For this reason, in order to be able to block the pipe line in response to an external electric signal, another blocking mechanism as described in Patent Document 2, Patent Document 3, and the like has to be added. Providing two mechanisms in this way is not preferable because it complicates the emergency shut-off valve device.

  Accordingly, an object of the present invention is to enable an emergency shutoff valve to operate in response to both detection of an overflow velocity and a signal from a seismometer or the like.

  In order to solve the above-described problems, the present invention provides a pressure release for releasing pressure in a cylinder chamber that leads to a pressure guiding pipe downstream of an orifice in an emergency shutoff valve provided with a differential pressure cylinder that is movable by a pressure difference before and after the orifice. A mechanism is provided, and the pressure release mechanism is operated by an external signal so that the pressure in the cylinder chamber is released. If it does in this way, the latching lever which latches the said arm can be rock | fluctuated according to the signal, and the latching can be cancelled | released.

  Since the present invention is configured as described above, it is possible to block the flow of the pipeline corresponding to both the detection of the overflow velocity and the electrical signal from the seismometer or the like.

  As a specific embodiment of the above means, a rotary valve having a valve body attached to a valve shaft inside a valve box is interposed in a pipe line, an arm is fixed to the valve shaft, and the arm is rotated in the vertical direction together with the valve shaft. It is possible to move. The arm is provided with a weight, and the fixed frame is provided with a locking lever that can swing in the vertical direction. The locking lever is locked to the arm to prevent the weight from being lowered. The body is kept open.

  Further, an orifice is provided in a pipe line upstream of the rotary valve, and a pressure guide pipe is connected to each of the upstream and downstream pipe lines before and after the orifice, and the pressures of both the pressure guide pipes are both cylinder chambers of the differential pressure cylinder. Introduce to. Based on the pressure difference, the piston rod of the differential pressure cylinder is operated to swing the locking lever to release the locking to the arm, and to rotate the arm by the weight of the weight. Thus, the valve body can be closed by rotating the valve shaft.

  In the emergency shutoff valve configured as described above, a pressure release mechanism using an electromagnetic valve is provided in the cylinder chamber of the pressure guiding pipe connected to the downstream side of the orifice or the differential pressure cylinder leading to the downstream pressure guiding pipe, and the electromagnetic The valve is operated to release the pressure in the cylinder chamber leading to the downstream pressure guiding pipe. The signal from the outside includes, for example, a signal emitted from a seismometer.

  In this way, in an emergency shut-off valve using a differential pressure cylinder that operates by detecting the overflow velocity of the pipeline, it can respond to electrical signals from seismometers, etc., simply by adding a pressure release mechanism using a solenoid valve. Therefore, the flow of the pipeline can be blocked. For this reason, both functions can be supported without complicating the apparatus.

  One embodiment will be described with reference to FIGS. As shown in FIG. 1, the emergency shutoff valve 1 of this embodiment has a rotary valve in which a valve body 2 is attached to a valve shaft 5 inside a valve box 3 interposed in a pipe P, and is connected to one end of the valve shaft 5. The arm 7 is fixed together with the valve shaft 5 so as to be rotatable in the vertical direction, and a weight 6 is provided at the tip of the arm 7. The frame 4 fixed to the valve box 3 is provided with a long locking lever 8 which is supported by a support pin 9 of the frame 4 so that it can swing up and down in the middle of its length. Has been.

  A locking hole 8a into which the pin 7a of the arm 7 is fitted is formed on the lower surface of one end of the locking lever 8, and the arm 7 is locked by fitting the locking hole 8a into the pin 7a. 8 prevents the weight 6 from descending and maintains the valve open state. Further, the rod 23 of the differential pressure cylinder 20 is connected to the other end 8b of the locking lever 8 as shown in FIG.

  As shown in FIG. 1, the differential pressure cylinder 20 includes two cylinder chambers 21 and 22 that sandwich a piston 23 a of a piston rod 23 in the differential pressure cylinder 20. The tip protrudes upward. A connecting member 24 is attached to the tip of the piston rod 23, and the connecting member 24 is connected to the other end 8b of the locking lever 8 via a pin 24a. For this reason, when the piston rod 23 of the differential pressure cylinder 20 moves back and forth, the locking lever 8 swings up and down around the pin 9.

  Further, an orifice 10 shown in FIG. 2 is provided in the pipe P on the upstream side of the rotary valve, and flowing water is taken out by the pressure guiding pipes 11 and 12 from the pipes P and P before and after the orifice 10. The flowing water of the pressure guiding pipes 11 and 12 is introduced into the two cylinder chambers 21 and 22 in the differential pressure cylinder 20, respectively, as shown in FIG. If the differential pressure before and after the orifice 10 increases due to the increase in the flow rate in the pipe P, and the pressure on the upstream side of the orifice 10 becomes greater than the pressure on the downstream side by a predetermined value or more, the piston resists the biasing force of the spring 23s. The rod 23 is pushed down to swing the locking lever 8 in the direction in which the locking hole 8a is raised.

  Further, the pressure guiding pipe 12 connected to the downstream side of the orifice 10 is provided with a pressure release mechanism 15 by an electromagnetic valve. In a normal state, the electromagnetic valve maintains the pressure guiding pipe 12 in a state where the pipe P on the downstream side of the orifice and the cylinder chamber 22 communicate with each other, and an electric signal from the seismometer 19 shown in FIG. When the electromagnetic valve is actuated by the signal received through the cable 14, the pressure release mechanism 15 opens the flowing water in the downstream pressure guiding pipe 12 through the discharge portion 13 to the atmosphere.

  The operation of the emergency shut-off valve 1 when an earthquake occurs will be described. When the seismometer 19 detects a seismic intensity of a predetermined value or more in a state where the arm 7 shown in FIG. The emergency release signal is received by the pressure release mechanism 15 via the cable 14. When the pressure release mechanism 15 receives the signal, the electromagnetic valve is activated, and the pressure in the downstream pressure guiding tube 12 is released to the atmosphere through the discharge portion 13 as shown in FIG. If the pressure in the downstream side pressure guiding pipe 12 is released and the pressure in the cylinder chamber 22 decreases, the pressure in the cylinder chamber 21 becomes relatively high, so the piston rod 23 is pushed down. As the piston rod 23 descends, the other end 8b of the locking lever 8 moves downward, and conversely swings in a direction in which the locking hole 8a at one end rises.

  By this swinging, the pin 7a is pulled out from the locking hole 8a, and the locking of the arm 7 is released. When the locking of the arm 7 is released, the weight 6 urges the arm 7 to rotate downward by its own weight, and the arm 7 rotates with the valve shaft 5 to rotate the valve body 2. Is closed, the flow of the pipe P is interrupted.

  In this embodiment, a pressure release mechanism 15 using an electromagnetic valve is provided in the pressure guiding pipe 12 connected to the downstream side of the orifice 10. The pressure releasing mechanism 15 is provided in the cylinder chamber 22 that communicates with the downstream pressure guiding pipe 12. As long as the pressure can be released, the installation location is not limited. For example, the pressure may be provided in the cylinder chamber 22. Further, the signal for operating the electromagnetic valve of the pressure release mechanism 15 may be issued from other than the seismometer.

In the front view of one Example, a valve closing state is shown. 1 is a perspective view of FIG. The figure which shows the valve opening state of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Emergency shut-off valve 2 Valve body 3 Valve box 4 Frame 5 Valve shaft 6 Weight 7 Arm 7a Pin 8 Locking lever 8a Locking hole 8b Other end 10 Orifice 11 Upstream pressure line 12 Downstream pressure line 13 Discharge part 14 Cable 15 Pressure release mechanism 20 Differential pressure cylinders 21 and 22 Cylinder chamber 23 Piston rod 23a Piston 24 Connection member 25 Damper 25a Damper rods 25b and 25c Damper fixing pin 26 Clutch 27 Handle 28 Manual open / close device 29 Electric open / close device

Claims (2)

A rotary valve having a valve body 2 attached to a valve shaft 5 inside the valve box 3 is interposed in the pipe P, and an arm 7 is fixed to the valve shaft 5, and the arm 7 is rotated up and down together with the valve shaft 5. A weight 6 is provided on the arm 7 as possible, and a fixed lever 4 is provided with a locking lever 8 that can be swung in the vertical direction. 6 to prevent the lowering of the valve body 2 and keep the valve body 2 open.
An orifice 10 is provided in the pipe P on the upstream side of the rotary valve, and pressure guiding pipes 11 and 12 are connected to the upstream and downstream pipes P and P before and after the orifice 10 to connect the pressure guiding pipes 11 and 12 to each other. Pressure is introduced into both cylinder chambers 21 and 22 of the differential pressure cylinder 20, and the locking lever 8 is swung by the operation of the piston rod 23 of the differential pressure cylinder 20 to unlock the arm 7. In the emergency shut-off valve 1 that rotates the arm 7 by its own weight and rotates the valve shaft 5 to close the valve body 2 by the rotation,
A pressure release mechanism 15 using an electromagnetic valve is provided in the pressure guiding pipe 12 connected to the downstream side of the orifice 10 or in the cylinder chamber 22 of the differential pressure cylinder 20 leading to the downstream pressure guiding pipe 12, and the electromagnetic valve is operated by an external signal. The emergency shut-off valve, wherein the pressure in the cylinder chamber 22 that operates and communicates with the downstream pressure guiding pipe 12 is released.   The emergency shut-off valve according to claim 1, wherein an external signal for operating the electromagnetic valve is emitted from a seismometer.

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