JPH11210908A - Valve element lock releasing device for emergency cutoff valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress lock release error small, to stably release a lock, to dispense with a power supply, to avoid a failure, to surely operate a valve in an emergency, to improve reliability, to use the valve at a place where no power supply can be secured, and to expand an operating range. SOLUTION: The hook face pressures of the lock faces 17a, 17b of a lock recess 17 and the lock face 18a of a topper 18 are adjusted, the coupled state of the lock faces 17a, 17b is held when water normally flows in a water conduit, and a stop shaft 11 is prevented from being moved. The stop shaft 11 is prevented from being moved by the lock face 18a bearing pressure until the water pressure of a pressure chamber 15 is lowered to a set value by an abnormal flow in the water conduit. When the water pressure of the pressure chamber 15 is lowered to the set value, the coupled state of the lock faces 17a, 17b is released by th excitation of a spring 3, the stop shaft 11 is retreated at a high speed, and an interference section 11A at the tip of the s stop shaft 11 is evacuated from a stop mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve lock release device for an emergency shutoff valve for urgently shutting off a water distribution line when an earthquake occurs.

[0002]

2. Description of the Related Art Conventionally, as an emergency shut-off valve having a function of automatically shutting off water flowing through a water distribution pipeline in an emergency such as when a water distribution pipeline is damaged in the event of an earthquake or the like, FIG.
And the structure shown in FIG. That is, the valve box 1
The valve element 2 housed therein is fixed to a valve stem 3. Valve stem 3
Are rotatably supported by the valve box 1, and both ends thereof are led out of the valve box 1. A base of an arm 5 is fixed to one end of the valve stem 3, and a weight 6 is attached to a distal end of the arm 5, and the arm 5 and the weight 6 constantly apply torque to the valve body 2 in a valve closing direction. The torque generating source 7 is configured to apply a torque in the valve closing direction to the valve body 2 by the valve closing torque generating source 7 to fully close the valve.

The stop mechanism 8 interferes with the valve closing torque generating source 7 to hold the valve body 2 at the fully open position shown by the solid line. When the interference of the stop mechanism 8 is released, the weight in the valve closing direction due to the weight of the weight 6 is reduced. To rotate the arm 5 and the valve rod 3 in the direction of arrow R to bring the valve body 2 into the fully closed state indicated by the imaginary line, and from the upstream pipe 9A to the downstream pipe 9 in the water distribution pipeline 9.
Block water flow to B.

The stop mechanism 8 includes a first link 8A pivotally connected to a fulcrum pin 8a and a second link 8A pivotally connected to a fulcrum pin 8b.
A link 8B, a third link 8C connecting the first link 8A and the second link 8B, and a spring 8D hooked on the first link 8A, and the arm is always provided in a locking recess 8d formed in the first link 8A. 5 and the stop pin 4 interferes with the one end side surface of the second link 8B, thereby restricting the operation of the stop mechanism 8 and the valve closing torque generating source 7, and Body 2 is held in the fully open position. The stop pin 4 is configured to be moved in the axial direction by energizing an electromagnet (not shown) and to be retracted from the side surface of one end of the second link 8B.

In the emergency shut-off valve configured as described above,
When the water distribution pipeline 9 is damaged due to the occurrence of an earthquake or the like, the damage is appropriately detected, and the electromagnet is energized. As a result, the stop pin 4 retreats at a high speed and retreats from the side surface of the one end of the second link 8B. With the retraction of the stop pin 4,
The first link 8A rotates clockwise by the spring force of the spring 8D. As a result, the first link 8A, the second link 8B, and the third link 8C are in the state of FIG.
The engagement between the locking recess 8d of the link 8A and the fixing pin 8E protruding from the arm 5 is released.
The arm 5 and the valve rod 3 are rotated in the direction of arrow R in FIG. 6 by the closing torque due to the weight of the weight 6 in the above, to bring the valve body 2 into the fully closed state shown by the imaginary line, and to communicate with the downstream pipe 9B. Shut off water.

The return of the valve body 2 from the fully closed position to the fully open position is performed by rotating the arm 5 and the weight 6 of the valve closing torque generating source 7 in the direction indicated by the arrow R by an operating device (not shown). When the electromagnet is de-energized when returning to the fully open position, the stop pin 4 moves forward by the bias of a spring (not shown) to interfere with the one end side surface of the second link 8B and stop. The mechanism 8 also returns to the state of interfering with the valve closing torque generating source 7, and holds the valve body 2 at the fully open position indicated by the solid line.

However, the conventional lock release device for an emergency shut-off valve is provided with a second link 8 in a stop mechanism 8.
Stop pin 4 that removably interferes with the side surface of one end of B
And an electromagnet that moves the stop pin 4 in the axial direction in an emergency and retracts from one end side surface of the second link 8B, so that a power supply for operating the electromagnet is required. For this reason, if a failure such as a disconnection occurs in the power supply circuit, malfunction may occur in an emergency and the valve may not be closed, and use in places where power cannot be secured, such as in mountainous areas, may occur. Has limited limitations.

On the other hand, there is a type in which the valve lock release device is constituted by a water pressure detection diaphragm mechanism replacing the electromagnet and a stop pin 4. In this type of valve body lock release device, the stop pin 4 is connected to one end of the second link 8B by the operation of the diaphragm which is taken into the diaphragm chamber (pressure chamber) of the water pressure detection diaphragm mechanism when the water distribution pipe 9 normally flows water. When the water pressure in the pressure chamber drops to a set value due to abnormal water flow in which the water distribution pipe 9 is damaged due to an earthquake or the like, the stop pin 4 is retracted by the spring force of the diaphragm urging spring. The second link 8B is retracted from the side surface at one end, and the valve body 2 is fully closed, so that water flow to the downstream pipe 9B can be shut off. In other words, since the power supply circuit is not required, it is possible to avoid the occurrence of a failure due to the disconnection of the power supply circuit of the valve lock release device, and to relax the use restriction to expand the use range.

However, due to the occurrence of an earthquake or the like, the water distribution pipeline 9
Is damaged, the water pressure in the pressure chamber falls to the set value relatively slowly, and the stop pin 4 moves back relatively slowly following this relatively slow water pressure drop. For this reason,
When the water pressure in the pressure chamber has dropped to the set value, the stop pin 4 is not always retracted from the side surface of the one end of the second link 8B. Stop pin 4 that interfered with a part of one side
Non-evacuated state. That is, the latter valve element unlocking device has a disadvantage that the unlocking error at the set pressure is large and the unlocking is unstable, resulting in a lack of reliability.

[0010]

That is, the valve lock release device of the emergency shut-off valve is configured to retreat the stop pin at a high speed by energizing the electromagnet and retreat from the stop mechanism when an abnormal situation occurs. Although the lock release error at the time of occurrence is small and the lock release can be performed stably, there is a possibility that an emergency operation failure due to the occurrence of a failure such as power supply circuit disconnection may occur, and as in mountainous areas There is a disadvantage that the use in places where power cannot be secured is limited, and the latter valve lock release device of the emergency shut-off valve can solve the problem of the former valve lock release device, There is a problem that the lock release error at the set pressure is large and the lock release is unstable because the lock release is unstable. Therefore, the present invention is designed to minimize the unlocking error at the time of occurrence of an abnormal situation, to stably perform unlocking, and to operate without requiring a power supply, thereby avoiding a failure. Emergency shut-off valve lock release device that can be operated reliably in an emergency, improve reliability, and can be used in places where power cannot be secured, such as mountainous areas, and can be used in a wider range. The purpose is to provide.

[0011]

In order to achieve the above object, an emergency lock valve unlocking device according to the present invention comprises:
A valve body housed in a valve box, a valve rod fixedly secured to the valve body and rotatably supported by the valve box and led out of the valve box; an arm fixed to the valve rod and attached to the arm A valve closing torque source that constantly applies a torque in the valve closing direction to the valve body, having a weight, a stop mechanism that interferes with the valve closing torque source and holds the valve body at the fully open position, During normal water flow in the water distribution pipe in which the valve box is provided, the stop mechanism is detachably interfered with the stop mechanism to maintain a fully open state of the valve body due to interference between the stop mechanism and the valve closing torque generation source, The interference between the stop mechanism and the valve closing torque generation source is canceled by canceling the interference with the stop mechanism during abnormal water flow in the water distribution pipeline, and the entire valve body is closed with the torque in the valve closing direction by the torque generation source. Valve lock release of emergency shut-off valve that allows closing In the apparatus, a stop shaft provided at an end thereof with an interference portion that removably interferes with the stop mechanism, a diaphragm attached to the stop shaft and interposed in a pressure chamber that takes in water pressure of the water distribution pipeline, When the diaphragm is actuated by the water pressure taken into the pressure chamber during normal water flow in the water pipe, the stop portion is advanced in the axial direction by allowing the stop shaft to advance to the front end position where the interference portion interferes with the stop mechanism. A spring for urging the stop shaft in the retreating direction by a force, a locking recess formed at the outer periphery of the stop shaft with a locking surface at an inlet is provided, and the interference portion interferes with the stop mechanism. At the front end position of the stop shaft, there is provided a stopper provided at the front end with a locking surface which engages with the locking surface of the locking recess so as to be able to advance and retreat. Until the water pressure in the pressure chamber decreases to a set value due to normal water flow, the engagement between the locking surface of the stopper and the locking surface of the locking recess is maintained to prevent the movement of the stop shaft. When the water pressure in the pressure chamber falls to a set value, the engagement between the locking surface of the stopper and the locking surface of the locking recess can be released by the bias of the spring. It is characterized in that it is configured so that the locking surface pressure between the surfaces can be adjusted.

According to the present invention, by adjusting the locking surface pressure, the engagement state of the locking surfaces is maintained during normal water distribution of the water distribution pipeline to prevent the stop shaft from moving, and the water distribution pipe is controlled. Until the water pressure in the pressure chamber drops to the set value due to abnormal water flow in the road, the stop shaft is prevented from moving by stepping on the locking surface pressure, and only when the water pressure in the pressure chamber drops to the set value. The engagement state between the locking surfaces is released by the bias of the spring, and the stop shaft is retracted at high speed,
The interference part at the tip of the stop shaft can be retracted from the stop mechanism.

[0013]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a valve lock release device for an emergency shutoff valve according to the present invention. In addition, valve box,
The valve body, the valve stem, the valve closing torque generation source, the stop mechanism, and the like are not different from those in FIGS. In FIG. 1, the valve lock release device of the emergency shut-off valve includes a stop shaft 11, a diaphragm 12, and a spring 13, and is accommodated in a cylinder 14.

The stop shaft 11 is mounted in the cylinder 14 so as to be freely movable in the axial direction. Interfering part 11A protruding and retracting from the distal end opening of cylinder 14 at the distal end of stop shaft 11
And a diaphragm 1 is provided at an intermediate portion of the stop shaft 11.
2 are installed. The diaphragm 12 is a pressure chamber 15
The pressure chamber 15 communicates with the water distribution line 9 via a port 15A and a pipe (not shown), and is configured to take in the water pressure of the water distribution line 9.

The rear end side of the stop shaft 11 is led out from the rear end opening of the cylinder 14, and the spring 13 is compressed and held between the spring retainer 16 mounted near the lead-out end and the rear end face of the cylinder 14. . This spring 13
When the water pressure at the time of normal water flow in the water distribution pipe 9 is taken into the pressure chamber 15, the diaphragm 12 operates to the right in FIG. 1, and the interference portion 11A interferes with the one end side surface of the second link 8B. The stop shaft 11 is compressed in the axial direction while allowing the forward movement of the stop shaft 11 to the front end position, and the stop shaft 11 is constantly urged in the backward direction by the compression reaction force.

A locking recess 17 formed by an annular groove is provided on the outer peripheral portion of the stop shaft 11, and a stopper 18 movably engaged with the locking recess 17 has an axis perpendicular to the axis of the stop shaft 11. Is attached to the cylinder 14. As shown in FIG. 2, a locking surface 17 a that is inclined obliquely rearward from the front end toward the axis and a diagonally forward direction from the rear end are provided at the outer peripheral end of the locking concave portion 17, that is, at the entrance of the locking concave portion 17. A locking surface 17b that is inclined toward the axis is formed.

The stopper 18 is provided at the front end position of the stop shaft 11 where the interference portion 11A of the stop shaft 11 interferes with the one end side surface of the second link 8B.
17b so as to be able to advance and retreat. That is, the stopper-1
Reference numeral 8 denotes an engagement pin 18A, a spring 18B, an adjustment bolt 18C, and a lock nut 18D. The engagement pin 18A and the spring 18B are axially movably inserted into a depth of a stopper insertion hole 14A provided in the cylinder 14. A locking surface 18a is provided at the distal end of the engaging pin 18A to engage with the locking surfaces 17a and 17b of the locking recess 17, and the distal end of the spring 18B contacts the rear end surface of the engaging pin 18A. I have. The adjusting bolt 18C is screwed into the female screw portion 14a formed in the stopper insertion hole 14A, and the tip of the adjusting bolt 18C contacts the rear end of the spring 18B. Therefore, by increasing the degree of screwing of the stopper insertion hole 14A to the female screw portion 14a, the locking surfaces 17a, 17
The locking surface pressure between the locking surfaces 17a, 17b and the locking surface 18a can be reduced by increasing the locking surface pressure between the locking surface 18b and the locking surface 18a and reducing the degree of screwing.

That is, by adjusting the locking surface pressure between the locking surfaces 18a, 17a, 17b, the locking surface 18a of the engaging pin 18A and the locking recess 17 during normal water flow in the water distribution pipeline 9 are provided.
While retaining the engagement state with the locking surfaces 17a and 17b to prevent the movement of the stop shaft 11, and until the water pressure in the pressure chamber 15 drops to the set value due to abnormal water flow in the water distribution pipeline 9. The stop shaft 11 is depressed by the locking surface pressure.
Is stopped, and only when the water pressure in the pressure chamber 15 drops to the set value is the engagement pin 1
8A locking surface 18a and locking recess 17 locking surface 17a, 1
3b, the stop shaft 11 is retracted at a high speed, and the interference portion 11A at the end of the stop shaft 11 is moved to the second link 8B in the stop mechanism 8 as shown in FIG.
Can be retracted from the side surface at one end.

For this reason, similarly to the energizing method in which the stop pin is retracted at a high speed by energizing the electromagnet described in the conventional example, the unlocking error in the event of an abnormal situation is suppressed to a small value, and the unlocking is performed stably. Can be. Moreover,
Since no power supply is required, operation can be ensured in an emergency, which improves reliability and allows use in places where a power supply cannot be secured, such as mountainous areas, thus expanding the range of use. .

In the above-described embodiment, the locking surface 17a which is inclined obliquely rearward from the front end toward the axis and the locking surface 17b which is inclined obliquely forward from the rear end toward the axis are formed. The locking recess 17 formed by the groove
1, as shown in FIG. 4 (A), a blind recessed circular hole-shaped locking recess 17 having a counterbore locking surface 17 a is provided on the periphery of the entrance. Is also good. Further, as shown in FIG. 4 (B), even a configuration in which a blind recessed rectangular hole-shaped locking recessed portion 17 having only a locking surface 17a inclined obliquely rearward from the front end toward the axis is provided. Good.

[0021]

As described above, according to the present invention, by adjusting the locking surface pressure, the engagement state between the locking surfaces is maintained during normal water flow in the water distribution pipeline, and the movement of the stop shaft is controlled. In addition to stopping the movement of the stop shaft by stepping on the locking surface pressure until the water pressure in the pressure chamber drops to the set value due to abnormal water flow in the water distribution pipeline, the water pressure in the pressure chamber is reduced to the set value. At the time when it drops to the first time, the engagement state of the locking surfaces is released by the bias of the spring for the first time, the stop shaft is retracted at high speed, and the interference part at the tip of the stop shaft can be retracted from the stop mechanism, The lock release error at the time of occurrence of an abnormal situation can be kept small, and the lock release can be performed stably. Moreover, since no power supply is required,
Since the operation can be reliably performed in an emergency, the reliability is improved, and the device can be used in a place where a power source cannot be secured, such as a mountain region, so that the range of use can be expanded.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing a locked state according to an embodiment of the present invention.

FIG. 2 is an enlarged view showing an example of a locking recess.

FIG. 3 is a longitudinal sectional view at the time of unlocking.

FIG. 4 is an enlarged sectional view showing a modified example of a locking recess.

FIG. 5 is a front view showing an example of an emergency shutoff valve.

FIG. 6 is a side view of FIG. 5;

FIG. 7 is a side view showing an operation state of a stop mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Valve box 2 Valve body 3 Valve rod 5 Arm 6 Weight 7 Valve closing torque generation source 8 Stop mechanism 9 Water distribution pipeline 11 Stop shaft 11A Interference part 12 Diaphragm 13 Spring 15 Pressure chamber 17 Locking recess 17a Locking surface 18 Stopper 18a Locking surface

Claims (1)

[Claims] 1. A valve body housed in a valve box, a valve rod fixedly supported by the valve box and rotatably supported by the valve box, and a valve stem led out of the valve box, and an arm fixed to the valve stem. A valve closing torque generating source having a weight attached to the arm to constantly apply a torque in the valve closing direction to the valve body; and interfering with the valve closing torque generating source to hold the valve body at the fully open position. A stop mechanism, and a fully opened state of the valve body due to interference between the stop mechanism and the valve closing torque generating source such that the stop mechanism is disengageably engaged with the stop mechanism during normal water flow in a water distribution pipe provided with the valve box. While holding the water distribution line abnormally, the interference between the stop mechanism and the valve closing torque generating source is released by canceling the interference with the stop mechanism, and the torque in the valve closing direction by the torque generating source is released. Emergency shutoff allowing full closure of the valve body A valve shaft unlocking device for the emergency shut-off valve, comprising: a stop shaft provided at an end with an interfering portion that removably interferes with the stop mechanism; and the stop shaft attached to the stop shaft. A diaphragm interposed in a pressure chamber that takes in the water pressure of the water pipe, and a front end position where the interference part interferes with the stop mechanism by the operation of the diaphragm by the water pressure taken into the pressure chamber during normal water flow in the water distribution pipe. A spring for compressing the stop shaft in the axial direction while allowing the stop shaft to advance, and for urging the stop shaft in the retreating direction by the compression reaction force, wherein a locking surface is formed at an inlet on an outer peripheral portion of the stop shaft. A stopper provided at a front end of the stop shaft where the interference portion interferes with the stop mechanism; A locking surface and a locking recess of the stopper during normal water flow in the water distribution line and until the water pressure in the pressure chamber drops to a set value due to abnormal water flow in the water distribution line. The stop shaft is prevented from moving by maintaining the engagement state with the locking surface of the stopper, and when the water pressure in the pressure chamber decreases to a set value, the locking surface of the stopper and the locking concave portion are urged by the spring. Characterized in that the locking surface pressure between the two locking surfaces can be adjusted so that the engagement state with the locking surface can be released. .