KR200224589Y1 - Opening and closing velocity control apparatus for hydraulic valve - Google Patents

Abstract

The present invention relates to an open / close speed control device of a hydraulically actuated butterfly valve. The open / close cross-sectional area in which the pressure applied to the valve disc is relatively small is opened and closed at the first stage open / close speed and the pressure applied to the valve disc. In the relatively large state of the open flow path cross section, the valve is opened and closed at the second stage opening and closing speed slower than the first stage opening and closing speed, thereby preventing damage to the valve.

Description

OPENING AND CLOSING VELOCITY CONTROL APPARATUS FOR HYDRAULIC VALVE}

The present invention relates to a hydraulic device of a hydraulically actuated valve, and in particular, a hydraulically driven butterfly that prevents damage to the valve by reducing the pressure applied to the valve during the normal closing operation, the normal opening operation, and the emergency closing operation. The opening and closing speed control device of the valve.

Generally, a hydraulic device is used to open and close a large valve such as a butterfly valve.

A general hydraulically actuated butterfly valve includes a hydraulic valve including a cylindrical valve body, a valve disc rotatably installed in the valve body, a hydraulic cylinder for opening and closing the valve disc, and a hydraulic cylinder for opening and closing the hydraulic cylinder. It is configured to include a hydraulic circuit for supplying oil.

When the hydraulically operated butterfly valve is operated by the control unit, power is applied to the solenoid valve open / close control valve to operate the open / close control valve to the open position, so that the open / close driving oil pressurized by the oil pump is open on the side of the hydraulic cylinder. When the piston rod of the hydraulic cylinder is reversed, the valve disc is rotated in the opening direction, and the opening / closing oil supplied during the closing operation flows out from the closing side port to return to the oil tank. When the power is cut off, the on / off control valve is operated in the closed position, and the oil for opening and closing operation pressurized by the oil pump is supplied to the closing side port of the hydraulic cylinder, so that the piston rod of the hydraulic cylinder moves forward, the valve disc rotates in the closing direction, The opening and closing drive oil that was supplied during the opening operation is leaked from the port. It is returned to the tank.

Thus, in order to maintain the open or closed state, an intermediate stop valve having an oil supply port and a shutoff port is installed between the pump line and the open / close control valve. In order to be connected through and maintained in a constant open or closed state, the blocking port is configured to be located between the pump line and the tank line and the open / close control valve.

On the other hand, in general, the butterfly valve is installed in a large pipe over 1000 mm in diameter, such as a water supply pipe, so that the opening and closing operation can be performed at high speed. In general, a check valve with a pilot and a throttle / check valve are installed in the middle of the open side hydraulic line and the close side hydraulic line to control the flow rate of the oil for opening and closing operation flowing through the open side hydraulic line and the closed side hydraulic line. It is designed to take more than 1 minute to fully open at full open or full open at full close by lowering.

In addition, when an emergency such as a power failure occurs, power is cut off to the solenoid valve open / close control valve to perform an emergency closing operation.

However, the conventional hydraulically operated butterfly valve has a wide open cross-sectional area of the butterfly valve at the time of closing operation, so there is no fear of damage to the valve even if the valve is closed at a predetermined closing speed due to the low pressure applied to the valve. As the flow path cross-sectional area of the butterfly valve decreases, the pressure applied to the valve is high, and if the valve closes at a predetermined closing speed, the valve may be damaged.In the opening operation, the opening operation proceeds to a certain degree. In the state where the cross-sectional area of the open flow path is wider than a certain level, there is no fear of damage to the valve even if the pressure applied to the valve is low, but the open flow path cross-sectional area of the valve is narrow before the opening operation to some extent High pressure to open at a set opening rate There was a risk of valve breakage.

In addition, conventional hydraulically operated butterfly valves are controlled by pilot check valves and throttle / check valves installed in the hydraulic line on the open side even in an emergency such as a power outage. There was a problem that can not cope.

Therefore, the inventor has devised an emergency closing device of a hydraulically operated butterfly valve such as Utility Model Registration No. 182633.

The emergency closing device of this pre-registration design connects the emergency closing oil return line between the tank line and the position closer to the hydraulic cylinder side than the throttle / check valve on the open side hydraulic line, and the power is turned on in the middle of the emergency closing oil return line. It is equipped with a shot-off valve that shuts off the emergency closing oil return line when it is applied and opens the emergency closing oil return line when the power is cut off.Oil returned to the oil tank from the open side port of the hydraulic cylinder during emergency closing operation. The emergency closing operation is performed quickly by returning to the oil tank through the emergency closing oil return line opened by the shot-off valve, so that the emergency closing operation can be performed quickly so that the emergency response can be promptly responded.

However, the hydraulically-operated butterfly valve employing the emergency closing device of the pre-registered design has the same problems as in the above-mentioned prior art in the normal closed and the normal open state, and the state in which the emergency closed operation has been advanced to some extent or in the open operation. In the state before the progress, there is a problem that the pressure applied to the valve is higher due to the higher flow rate of the opening and closing driving oil in the state in which the open flow passage cross-sectional area of the valve is narrower, and thus the valve breakage is more serious.

Therefore, the present invention aims to provide an opening / closing speed control device for a hydraulically operated butterfly valve that can prevent damage to the valve by reducing pressure applied to the valve during the normal closing operation, the normal opening operation, and the emergency closing operation.

1 is a side view and a hydraulic system of the valve showing a normal open state of the hydraulically actuated butterfly valve to which the opening and closing speed control device according to the present invention is applied.

2 is a front view of the valve of FIG.

Figure 3 is a side view and a hydraulic system of the valve showing a normal close (normal) state of the hydraulically operated butterfly valve to which the opening and closing speed control apparatus according to the present invention is applied.

4 is a front view of the valve of FIG.

Figure 5 is a side view and a hydraulic system showing an intermediate stop state of the hydraulic drive-type butterfly valve to which the opening and closing speed control apparatus according to the present invention is applied.

Figure 6 is a front view and a hydraulic system of the valve showing the emergency close (emergency close) state of the hydraulic drive-type butterfly valve to which the opening and closing speed control apparatus according to the present invention is applied.

7 is a side view showing a state in which the open / close speed control valve is spaced apart from the valve operation piece.

8 is a side view showing a state in which the open / close speed two-stage control valve is in contact with the valve operation piece.

9 is a partial side view and a front view showing the installation state of the valve operation piece.

** Description of symbols for the main parts of the drawing **

1: valve body 2: valve disc

12: hydraulic cylinder 13a: opening side port

13b: closed port 21: oil tank

22: oil pump 23a: open side hydraulic line

23b: Closed side hydraulic line 24a: Pump line

24b: main tank line 24c: auxiliary tank line

25: on-off control valve 30: emergency return oil return line

31: shot-off valve 40: opening and closing speed two-stage control valve

41: intermittent valve portion 42: connection port

43: blocking port 44: interlocking projection

45: elastic member 50: valve operation piece

Cylindrical valve body and to achieve the object of the present invention; A valve disc rotatably installed in the valve body; A hydraulic opening / closing mechanism including a hydraulic cylinder for opening and closing the valve disc and a link mechanism for transmitting a linear motion of the hydraulic cylinder to the valve disc with rotational force; An oil tank for storing the opening and closing driving oil, a main oil pump for compressing the opening and closing driving oil of the oil tank, an opening side hydraulic line connected to the opening side port of the hydraulic cylinder, and a closing side port of the hydraulic cylinder A closed side hydraulic line connected to the main line, a pump line connected to the main oil pump, a tank line connected to the oil tank, the open side hydraulic line, a closed side hydraulic line and the pump line is installed between the tank line A hydraulic circuit having valves for selectively connecting the main oil pump to the open side port and the close side port of the hydraulic cylinder and controlling the flow rate of the oil for opening / closing driving, wherein the valve is interlocked with the hydraulic opening / closing mechanism. In the state where the cross section of the open channel is relatively small, the pressure on the disk is opened and closed at the first stage opening and closing speed. Hydraulically driven butter, characterized in that it is provided with the opening and closing speed two-stage control means for opening and closing at a second opening and closing speed slower than the first opening and closing speed in a state in which the open channel cross-sectional area is narrow when the pressure applied to the screed is relatively large. Opening and closing speed control of the fly valve is provided.

The opening / closing speed two-stage control means is a valve operation piece attached to a link mechanism constituting the hydraulic opening and closing mechanism, an intermittent valve portion for regulating the open side hydraulic line and an open and closed hydraulic line when the intermittent valve portion is blocked. It consists of an opening / closing speed two-stage control valve having a throttle / check valve section for reducing and bypassing the flow rate of the driving oil and an intermittent valve section.

The intermittent valve portion has a connection port for connecting the normally open side hydraulic line, and a blocking port for blocking the open side hydraulic line when operated by the valve operation piece, the outer end is provided with a interlocking protrusion protruding, the inner end It is composed of an elastic member for elastically supporting the connection port to be in a state of connecting the open side hydraulic line.

The valve operation piece is coupled by forming a plurality of through holes and fastening the bolts penetrating the through holes to the screw holes formed in the link mechanism.

The plurality of through-holes are formed so as to be able to adjust the position in which the valve operation piece presses the interlocking projection of the intermittent valve part by being formed vertically long.

Hereinafter, the opening and closing speed control device of the hydraulically driven butterfly valve according to the present invention will be described in detail according to the embodiment shown in the accompanying drawings.

1 illustrates an example of a hydraulically actuated butterfly valve to which an opening and closing speed control device according to the present invention is applied.

As shown in FIG. 1, the hydraulically actuated butterfly valve to which the present invention is applied is rotatably installed at both ends of a cylindrical valve body 1 and support shafts 2a and 2b on the valve body 1. A valve disc 2 for opening and closing an intermediate portion of the valve body 1, a hydraulic opening and closing mechanism 10 coupled to one support shaft 2a of the valve disc 2 to open and operate the valve disc 2, It is configured to include a hydraulic circuit 20 for supplying the hydraulic pressure for opening and closing operation to the hydraulic opening and closing mechanism (10).

A valve seat 1a is formed on an inner circumferential surface of the valve body 1, and an outer circumference of the valve disc 2 is formed in a rounded shape so as to be in close contact with the valve seat 1a.

Receiving portions 3a and 3b supporting the support shafts 2a and 2b are formed on both sides of the outer circumferential surface of the valve body 1.

The hydraulic opening / closing mechanism 10 includes an opening / closing mechanism body 11 installed at one side of the valve body 1, a hydraulic cylinder 12 installed at the opening / closing mechanism body 11, and the hydraulic cylinder 12. It consists of a link mechanism 14 for transmitting a linear reciprocating motion to the one side support shaft (2a) with a rotational force.

The hydraulic cylinder 12 is vertically fixed to the opening and closing mechanism body 11 is installed so that the piston rod 12a protrudes downward.

The link mechanism 14 has a first link 15 connected to the piston rod 12a of the hydraulic cylinder 12 by a hinge pin 15a and one end fixed to the one side support shaft 2a, and the other end thereof. The second link 16 is connected to the first link 15 by a hinge pin 16a.

One side of the opening and closing mechanism body 11 is provided with an opening and closing angle indicator 17 for displaying the rotation angle of the support shaft (2a, 2b) and the valve disk (2).

The opening and closing angle indicator 17 is composed of an indicator 17a fixed coaxially with the one side support shaft 2a and an indicator disc 17b fixed to the opening and closing mechanism body 11.

The indicator disk 17b is marked with a scale 17c indicating the opening and closing and opening and closing angles.

The hydraulic circuit 20 includes an oil tank 21 for storing the oil for opening and closing driving, a main oil pump 22 for compressing the oil for opening and closing driving of the oil tank 21, and the hydraulic cylinder 12. The opening side hydraulic line 23a connected to the opening side port 13a, the closing side hydraulic line 23b connected to the closing side port 13b of the hydraulic cylinder 12, and the main oil pump 22. Pump line 24a connected to the main tank line 24b connected to the oil tank 21, auxiliary tank line 24c, the open side hydraulic line 23a and the closed side hydraulic line 23b. ) And the pump line 24a are installed between the main tank line 24b to selectively connect the main oil pump 22 to the open side port 13a and the closed side port 13b of the hydraulic cylinder 12. And an opening / closing control valve 25 for selectively connecting the oil tank 21 to the open side port 13a and the close side port 13b of the hydraulic cylinder 12. .

The open / close control valve 25 has a P ↑ A port 25a and a B ↓ T port 25b at a first position where power is applied, and P↗ at a second position when power is cut off. A 4 port 2 position solenoid valve with a B port 25c and an A 포트 T port 25d is used.In the open position with the power applied, the P ↑ A port 25a is opened by the solenoid action. The pump line 24a is connected to the open side hydraulic line 23a, and the B ↓ T port 25b is connected to the main tank line 24b and the closed side hydraulic line 23b. In the closed position, the P B B port 25c connects the pump line 24a and the closing side hydraulic line 23b by the restoring force of the spring, and the A↘T port 25d opens the opening side hydraulic line 23a. And the main tank line 24b and the auxiliary tank line 24c are installed to be in a state of connecting.

An intermediate stop valve 26 is installed between the open / close control valve 25 and the pump line 24a and the main tank line 24b.

The intermediate stop valve 26 has a P ↑ X port 26a and an X ↓ T port 26b at a first position located when power is applied, and P↗ at a second position located when the power is cut off. A 4-port 2 Position solenoid valve with a B port 26c and an X↘T port 26d is used, and in the energized open / closed operating position, the P↗B port 26c is the pump line 24a. ) Is selectively connected to the P ↑ A port 25a or P↗B port 25c of the open / close control valve 25, and the P ↑ X port 26a is pumped at the intermediate stop position where the power is cut off. It is connected so that it may be connected to the line 24a, and the X ↓ T port 26b will be connected to the main tank line 24b.

Between the open / close control valve 25 and the ports 13a, 13b of the hydraulic cylinder 12, the check valves 27a, 27b with a pilot, the throttle / check valves 28a, 28b, and the stop valves 29a, 29b Is installed.

An emergency closing oil return line 30 is connected between the throttle / check valves 28a and 28b of the opening side hydraulic line 23a and the stop valves 29a and 29b and between the main tank line 24b. The shot off valve 31 is provided in the middle of the emergency closing oil return line 30.

The shot-off valve 31 has an A ↓ T port 31a in the first position, and a two-port two-position solenoid valve in which the shutoff port 31b is installed is used in the second position, and when the power is applied, the solenoid action is performed. The A ↓ T port 31a is connected to the emergency closing oil return line 29, the auxiliary tank line 24c and the main tank line 24b by means of a spring restoring force when the power is cut off. 31b) is connected to the emergency closing oil return line 29 and the main tank line (24b) is installed so that the oil supply and oil return is not made.

The shutoff port 31b of the shot-off valve 31 may be configured in a state in which the port itself is closed, but it is preferable to install bidirectional check valves 31c and 31d for more reliable shutoff.

In the drawings, reference numeral 22a is a driving motor for driving the main oil pump 22, 32 is a manual oil pump for manually generating hydraulic pressure when a malfunction of the main oil pump 22 is performed, and 33a and 33b are Each is a check valve and 34 is a pressure gauge.

Hereinafter, the opening and closing operation of the hydraulically driven butterfly valve according to the present invention.

First, when the closing operation is performed in the control room in the open state as shown in FIG. 1, the power to the on / off control valve 25 and the intermediate stop valve 26, which are solenoid valves, are shut off as shown in FIG. 3. The control valve 25 and the intermediate stop valve 26 retreat (move to the right in the drawing) by the restoring force of the spring so that the pump line 24a and the closing side hydraulic line 23b are connected to the port of the intermediate stop valve 26 ( It is connected through the P↗B) and the port (P↗B) of the open / close control valve 25, and the open side hydraulic line (23a) and the main tank line (24b) is connected to the port (A↘T) of the open / close control valve (25). The oil supplied to the pump line 24a by being switched to the connected state through the oil pump 22 is supplied to the port P↗B of the intermediate stop valve 26 and the port of the on / off control valve 25. It is supplied to the closing side port 13b of the hydraulic cylinder 12 through P↗B) and the closing side hydraulic line 23b to transfer the piston rod 12a. In the opening side port 13a of the hydraulic cylinder 12, the oil introduced in the opening operation flows out, and the port A↘T and the main opening of the opening side hydraulic line 23a and the opening / closing control valve 25 are discharged. It returns to the oil tank 21 via the tank line 24b.

Accordingly, the first link 15 connected to the piston rod 12a of the hydraulic cylinder 12 by the hinge pin 15a rotates in a clockwise direction and descends, and is connected to the first link 15 by the hinge pin 16a. The second link 16 is rotated in the clockwise direction, so that the one side support shaft 2a on which the second link 16 is fixed is rotated in the clockwise direction so that the valve disc 2 is rotated in the clockwise direction. As shown in FIG. 3, it is in a closed state.

When the opening operation is performed in the control room in the closed state as shown in FIG. 3, as shown in FIG. 1, the intermediate stop valve 26 is maintained in a state where the power is cut off, and the power is supplied to the open / close control valve 25. The on / off control valve 25 is advanced by the operation of the solenoid (moving in the left direction in the drawing) so that the pump line 24a and the open side hydraulic line 23a are connected to the port P 124B of the intermediate stop valve 26. ) Is connected to the opening / closing control valve 25 via a port (P ↑ A), and the closing hydraulic line (23b) and the main tank line (24b) are connected to the opening / closing control valve (25) via a port (P ↓ B). The hydraulic cylinder is switched to the connected state and pressurized by the oil pump 22 to supply the pump line 24a to the hydraulic cylinder through the opening side hydraulic line 23a through the port P ↑ A of the open / close control valve 25. Supplied to the open side port 13a of 12 to retract the piston rod 12a (upward movement in the drawing). In the closed side port 13b of the hydraulic cylinder 12, the oil flowing in during the closing operation flows out and the closed side hydraulic line 23b, the port B ↓ T of the open / close control valve 25, and the main tank. Return to oil tank 21 via line 24b.

Accordingly, the first link 15 connected to the piston rod 12a by the hinge pin 15a is rotated in the counterclockwise direction, and thus the one side support shaft 2 on which the second link 16 is fixed is raised. This counterclockwise rotation causes the valve disc 2 to rotate counterclockwise so as to be opened as shown in FIG.

In addition, when power is applied to the intermediate stop valve 26 in the state in which the above-described opening and closing operation is completed, the intermediate stop valve 26 is advanced by the solenoid action (moves to the left in the figure) and the port P ↑ X is connected to the pump line ( 24a), the ports X ↓ T are switched to the main tank line 24b, respectively, so that oil supplied from the oil pump 22 to the pump line 24a is shut off at the port P ↑ X. , The oil returned to the oil tank 21 from the hydraulic cylinder 12 through the open side hydraulic line 23a or the closed side hydraulic line 23b is blocked at the port X ↓ T and is supplied to the hydraulic cylinder 12. Therefore, the open or closed oil is stagnated to maintain the open or closed state.

At this time, the oil returned from the open side hydraulic line 23a or the closed side hydraulic line 23b reaches the check valves 27a and 27b with pilot through the throttle / check valves 28a and 28b. The oil supplied from (24a) is blocked by the P ↑ X port 26a of the intermediate stop valve 26, so that no hydraulic pressure acts on the pilot line of the check valves 27a and 27b with pilot, so that the hydraulic line on the open side Since the oil returned from the 23a or the closing side hydraulic line 23b is blocked by the pilot check valves 27a and 27b, the intermediate stop action is accurately performed.

On the other hand, when the power is interrupted, the power supply of the on-off control valve 25, which is a solenoid valve, is cut off and automatically switched to the closed operation state, and the power of the shot-off valve 31 is also cut off. The valve 31 switches to a state in which the A ↓ T port 31a corresponds to the emergency closing oil return line 30 by the restoring force of the spring, and checks the oil coming out of the open side hydraulic line 23a with a pilot. A ↓ T port 31a and auxiliary tank line 24c of the emergency return oil return line 30 and the shot-off valve 31 immediately without passing through the valves 27a and 27b and the throttle / check valves 28a and 28b. Return to the oil tank 22 through the main tank line (24b) and the flow of the oil to operate the hydraulic cylinder 12 is made quickly, and as a result the butterfly valve is quickly closed.

This configuration and action is the same as the hydraulically-operated butterfly valve to which the emergency closing device of the pre-registration design described above is applied, and will be described below the main configuration and action of the present design.

The present invention provides a first stage opening / closing speed determined by the opening / closing control valve 25 and the throttle / check valves 28a and 28b, and a second stage opening / closing speed lower than the first opening / closing speed. Opening and closing speed two-stage control means is provided.

The opening / closing speed two-stage control means is installed in the middle of the opening side hydraulic line 23a to control the opening side hydraulic line 23a, and the intermittent valve portion 41 is the opening side hydraulic line 23a. ) Is attached to the link mechanism 14 and the opening / closing speed two-stage control valve 40 having a throttle / check valve section 46 for decelerating and bypassing the flow rate of the opening and closing driving oil when shut off. And a valve operation piece 50 for operating the intermittent valve portion 41 of the speed two-stage control valve 40.

The intermittent valve part 41 has a connection port 42 for connecting the normally open side hydraulic line 23a and a blocking port for blocking the open side hydraulic line 23a when operated by the valve operation piece 50. (43), the outer end is provided with an interlocking projection (44) protruding, the inner end of the elastic member 45 to elastically support so that the connection port 42 is connected to the opening side hydraulic line (23a) It is composed of

That is, the intermittent valve part 41 is always maintained by the elastic member 45 in a state where the connection port 42 connects the open side hydraulic line 23a, and the closing operation has been progressed to some extent. When the interlocking protrusion 44 is pressed by the valve operation piece 50, the blocking port 43 is installed so as to block the opening side hydraulic line 23a.

The throttle / check valve part 46 receives the opening and closing driving oil returned from the opening side port 13a of the hydraulic cylinder 12 when the control valve part 41 blocks the opening side hydraulic line 23a. It is configured to decelerate while passing.

As shown in FIG. 9, the valve operation piece 50 is a block that is integrally rotated with a hinge pin 16a connecting the first link 15 and the second link 16 of the link mechanism 14 ( It is coupled to 16b) and is installed at a position where the interlocking protrusion 44 of the intermittent valve part 41 can be pressed when the closing operation is carried out to some extent (for example, about halfway).

In addition, a plurality of (two in the drawings) through holes 51 are formed in the valve operation piece 50, and bolts 52 penetrating the through holes 51 are formed in the block 16b. The valve operating piece 50 is fixed to the link mechanism 14 by fastening to the thread hole 53.

In addition, the plurality of through holes 51 are formed to be vertically long so that the position of the valve operation piece 50, that is, the position where the valve operation piece 50 presses the interlocking protrusion 44 of the intermittent valve part 41. It is desirable to be able to control.

Hereinafter, the operation of the opening and closing speed control device of the hydraulically driven butterfly valve according to the present invention.

Closed operation

As the state in which the valve operation piece 50 coupled to the second link 16 does not press the interlocking projection 44 of the intermittent valve portion 41 until the closing operation is performed to some extent from the initial closing operation (FIG. 7). The opening and closing driving oil returned from the opening side port 13a of the hydraulic cylinder 12 is connected to the connecting port 42 by the opening side hydraulic line 23a connected to the connecting port 42 of the control valve part 41. ), It is returned to the oil tank 21 through the opening side hydraulic line 23a and the tank line 24b, so that the closing operation is performed at the first stage closing speed controlled by the usual throttle / check valves 28a and 28b. When the closing operation progresses to a certain degree and the valve manipulation piece 50 presses the interlocking protrusion 44 of the intermittent valve part 41 (FIG. 8), the opening side hydraulic line 23a is connected to the intermittent valve part ( Opening / closing drive oil blocked by the blocking port 43 of 41 and returned from the opening side port 13a of the hydraulic cylinder 12 is Since returning to throttle / check tank line (24b) after the deceleration through the valve unit 46 until they are fully closed after the closing operation in the first stage the second stage slow closing speed than the closing speed will be written.

Open operation

From the beginning of the opening operation until the opening operation to some extent, the valve operation piece 50 coupled to the second link 16 is in a state in which the interlocking projection 44 of the intermittent valve portion 41 is pressed (FIG. 8). Accordingly, the opening and closing driving oil supplied to the opening side port 13a of the hydraulic cylinder 12 through the opening side hydraulic line 23a is blocked by the blocking port 43, and the throttle / Since it passes through the check valve portion 46 is opened at a second stage opening speed slower than the first stage opening speed determined by the usual throttle / check valve (28a, 28b) and the like, the opening operation proceeds to some extent to the valve When the operation piece 50 does not press the interlocking protrusion 44 of the control valve part 41 (FIG. 7), the connection port 42 of the control valve part 41 connects the open side hydraulic line 23a. The opening and closing driving oil supplied from the tank line (23a) of the hydraulic cylinder 12 through the connection port 42 Is supplied to rimcheuk port (13a) is opened to the first end opening speed determined by a conventional throttle / check valve (28a, 28b).

Emergency closing operation

When the power supply is stopped due to a power failure, the shotoff valve 31 opens the emergency closing oil return line 30 to return to the oil tank 21 from the open side port 13a of the hydraulic cylinder 12. The oil for opening and closing the drive returns to the oil tank 21 through the emergency closing oil return line 30 and the shot-off valve 31 quickly, in which case the opening side hydraulic line 23a controls the opening and closing speed of the second stage. Since it is connected by the connection port 42 of the intermittent valve part 41 constituting the valve 40, the closing operation is performed at the first stage emergency closing speed.

Here, the oil returned at the initial stage of the emergency closing is first connected through the connection port 42 of the control valve part 41, the opening side hydraulic line 23a, the shot-off valve 31, and the emergency closing oil return line 30. However, when the emergency closing operation is progressed to a certain degree, the valve operation piece 50 presses the interlocking protrusion 44 of the intermittent valve part 41 of the opening / closing speed two-stage control valve 40 when the emergency closing operation is performed. FIG. 8), and thus the opening side hydraulic line 23a is blocked by the blocking port 43 of the control valve part 41 and returned from the opening side port 13a of the hydraulic cylinder 12. The oil is decelerated by the throttle / check valve part 46 of the opening / closing speed two-stage control valve 40, and then the oil is opened through the hydraulic line 23a on the open side, the emergency return oil return line 30, and the tank line 24b. Since it is returned to the tank 21, the closing operation is made at the second stage emergency closing speed slower than the first stage emergency closing speed. Will.

As described above, according to the opening / closing speed control device of the hydraulically actuated butterfly valve according to the present invention, the opening and closing section of the hydraulic drive butterfly valve opens and closes at the first stage opening / closing speed in a state where the pressure applied to the valve disk is relatively small. In a state in which the open passage cross-sectional area of a relatively high pressure is narrow, opening and closing at a second opening / closing speed slower than the first opening / closing speed can be prevented from damaging the valve.

In addition, the present invention is not only applied to the hydraulically-driven butterfly valve having the above-mentioned hydraulic circuit, but can also be applied to a hydraulically-driven butterfly valve employing a simple hydraulic circuit such as an on / off control valve. Various modifications can be made by those skilled in the art within the scope.

Claims (5)

A cylindrical valve body; A valve disc rotatably installed in the valve body; A hydraulic opening and closing mechanism including a hydraulic cylinder for opening and closing the valve disc and a link mechanism for transmitting linear movement of the hydraulic cylinder to the valve disc with rotational force; An oil tank for storing the opening and closing driving oil, a main oil pump for compressing the opening and closing driving oil of the oil tank, an opening side hydraulic line connected to the opening side port of the hydraulic cylinder, and a closing side port of the hydraulic cylinder A closed side hydraulic line connected to the main line, a pump line connected to the main oil pump, a tank line connected to the oil tank, the open side hydraulic line, a closed side hydraulic line and the pump line is installed between the tank line A hydraulic circuit having valves for selectively controlling a main oil pump to an open side port and a closed side port of a hydraulic cylinder, and to control a flow rate of oil for opening and closing driving, The open flow passage cross-sectional area in which the pressure applied to the valve disc is relatively small in connection with the hydraulic opening / closing mechanism is opened and closed at the first stage opening / closing speed in a wide state. In the opening and closing speed control apparatus of the hydraulically actuated butterfly valve characterized in that it comprises a two-stage control means for opening and closing at a second opening and closing speed slower than the first stage opening and closing speed. 2. The opening and closing speed control unit according to claim 1, wherein the opening / closing speed two-stage control means includes a valve operation piece attached to a link mechanism constituting the hydraulic opening / closing mechanism, an intermittent valve portion for intermitting the open side hydraulic line, and the intermittent valve portion open side hydraulic pressure. The opening and closing speed control of the hydraulically actuated butterfly valve, characterized in that the line consists of a two-speed control valve having a throttle / check valve section for reducing and bypassing the flow rate of the opening and closing drive oil when the line is blocked and an intermittent valve section. Device. According to claim 2, The intermittent valve portion has a connection port for connecting the normally open side hydraulic line, and a blocking port for blocking the open side hydraulic line when operated by the valve operation piece, the outer end is interlocked projection Protrudingly installed, the opening and closing speed control device of the hydraulically-actuated butterfly valve, characterized in that the inner end is composed of an elastic member for elastic support so that the connection port is connected to the open side hydraulic line. 3. The opening and closing speed of the hydraulically actuated butterfly valve according to claim 2, wherein the valve operation piece is coupled by fastening a bolt penetrating the through hole to a screw hole formed in the link mechanism. Control unit. [5] The opening and closing speed of the hydraulically actuated butterfly valve according to claim 4, wherein the plurality of through holes are formed to be vertically long so as to adjust the position at which the valve manipulation piece presses the interlocking projection of the intermittent valve portion. Control unit.