JPS6212428B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pressure equalizing device for a rotary valve, and more particularly to a pressure equalizing device for a rotary valve that substantially equalizes the pressure upstream and downstream of a valve body to reduce the opening and closing torque when the rotary valve is opened and closed. It is something.

(Prior Art) As a conventional device of this kind, there is one filed by the applicant of the present invention [Japanese Patent Application No. 101598/1983 (Japanese Patent Application Laid-open No. 226770/1989)]. As shown in FIG. 1, a main valve element 4' that opens and closes a flow path is rotatably disposed inside a valve body 1', and the main valve element 4' is attached to the valve body 1'.
The inner end of a rotary main valve shaft 7' which is supported by a bearing part is fixed, and an auxiliary valve shaft 17' which is slidable in the axial direction of the main valve shaft 7' is attached to the center of the main valve shaft 7'. Provided, sub-valve shaft 1
A communication hole 21' that communicates with the upstream side of the main valve body 4' in the valve body 1' is bored in the main valve shaft 7' around a part of the valve body 7', and a sub-hole for opening and closing the communication hole 21' is provided. The valve body 16' is fixed to the inner end of the auxiliary valve shaft 17', and the main valve body operating lever 28' for rotating the main valve shaft 7' is attached to the outer end of the main valve shaft 7'.
and an auxiliary valve body operation lever 28a' for sliding the auxiliary valve shaft 17' is provided at a close position outside the valve body 1' at the outer end of the auxiliary valve shaft 17', and the auxiliary valve body 4' is A compression spring 33' is provided as a biasing member that always biases in the closing direction. In addition, 22' is a communication hole bored in the valve box 1', 23' is a communication hole bored in the valve seat holding member 15', and these communication holes 22' and 23' are connected to the communication hole 21' and the valve It communicates with the downstream side of the main valve body 4' inside the box 1'. Also, 1
0' is the valve body valve seat, and 18' is the valve seat for the sub-valve body.

However, in the conventional device, the communication hole 2 provided in the valve box 1' and the valve seat holding member 15'
2', 23' are relatively long, and the communicating holes 21', 22',
Since the entire length of 23' becomes longer, there is a problem that the pressure loss becomes large and the pressure equalization time becomes long, resulting in poor operability.

(Problem) A technical object of the present invention is to shorten the overall length of the communication hole to minimize pressure loss.

(Technical means) The technical means taken to solve the above technical problem is to provide communication between the communication hole drilled in the main valve shaft and the downstream side of the main valve body in the valve box. The second communication hole is formed in the main valve body.

(Operation of technical means) In the fully closed state, when the sub-valve shaft is slid inward of the valve body against the biasing force of the biasing member by operating the sub-valve body control lever, the sub-valve shaft The auxiliary valve body fixed to opens the communication hole, thereby communicating the upstream and downstream sides of the valve box through the communication hole and the second communication hole, and the pressures upstream and downstream of the main valve body are almost equal. becomes.
At this time, since the second communication hole is provided in the main valve body and the length of the entire communication hole including the second communication hole is shortened, the pressure loss becomes extremely small. As a result, the pressure equalization time is shortened and operability is improved. As a result of the above, the differential pressure acting on the main valve element disappears, and the main valve element is rotated with a small force by the main valve element operation lever, opening the flow path and becoming fully open. Thereafter, when the operation lever for the sub-valve element is released, the sub-valve shaft is slid toward the outside of the valve body by the biasing member, and the sub-valve element closes the communication hole. To return from the fully open state to the fully closed state again, after opening the sub-valve body as described above, the main valve body is rotated in the opposite direction to close the flow path, and then the sub-valve body is closed.

(Special effects) Unlike conventional equipment, there is no need to provide a communication hole in the valve box, so in addition to making it easier to mold the valve box,
The second communicating hole provided in the main valve body may be a cast hole or a machined hole, which has the advantage that manufacturing costs are low.

(Example) Examples of the present invention will be described below.

In FIGS. 2 and 3, 1 is a valve box, and this valve box 1 has an inlet 2 formed on one side and an outlet 3 formed on the other side. Reference numeral 4 denotes a main valve body rotatably disposed within the valve body 1, and has horizontal mounting portions 5, 5a integrally connected to the upper and lower ends thereof, and the mounting portion 5 is attached to a bearing portion on the upper wall of the valve body. The mounting portion 5a is connected to the upper end of a support pin 8 that is vertically supported on the bottom wall of the valve box. has been done. The outer peripheral edge of the main valve body 4 is formed into an inclined surface 9. An annular hollow valve box valve seat 10 is disposed on the inner wall of the valve box on the side of the outlet 3 from the main valve body 4, and the valve seat 10 is made of an elastic material and has a valve seat main body 11 having a substantially U-shaped cross section. and a ring 12 made of a rigid material such as metal and fixed to the inner wall of the valve box on the outer peripheral side of the valve seat body 11. The outer circumferential surface of the valve seat body 11 on the main valve body 4 side is formed into an inclined surface 13 that comes into close contact with the inclined surface 9 when the valve is closed. In addition, a through hole 14 is bored on the outer peripheral side of the valve seat body 11 adjacent to the inclined surface 13, so that the hollow interior of the valve seat 10 of the valve box communicates with the inside of the valve box 1 on the side of the inlet 2. There is. A short hollow cylindrical valve seat holding member 15 is disposed on the inner wall of the valve box on the side of the outlet 3 from the valve seat 10 of the valve box and is screwed into the valve box from the outlet 3 side of the valve box 1. The side wall of the valve seat main body 11 on the outlet 3 side is held down and fixed in the valve box 1 at the end face.

A sub-valve shaft 17, which has a sub-valve body 16 at its lower end and is movable up and down, is provided in the center of the main valve shaft 7 and extends vertically through the main valve shaft 7. 18 is a valve seat for the sub-valve body 16 fixed to the lower end surface of the main valve shaft 7.

An annular groove 19 is formed outwardly on the outer periphery of the main valve shaft 7 at the fitting portion between the main valve shaft 7 and the mounting portion 5 of the main valve body 4 . The upper end of the main valve shaft 7 has a sub-valve shaft 1.
An annular hole 20 is formed that extends around 7 in the axial direction and is open at the upper end. Further, an annular groove 21 extending in the axial direction is formed on the outer periphery of the lower end of the sub-valve shaft 17, and the annular groove 21 and the annular groove 19 are connected to the lateral communication hole 2.
2 is connected.

Reference numeral 23 denotes a communication hole (second communication hole) formed at an angle from the mounting portion 5 toward the main valve body 4;
3 has one end opening into the annular groove 19 and the other end opening into the front wall of the main valve body 4, and when the sub valve body 16 is opened when the main valve body 4 is closed, the valve box on the inlet port 2 side is opened. Inside and inside the valve box on the outflow port 3 side are the annular groove 21 and the communication hole 2.
2, the annular groove 19 and the communication hole 23 communicate with each other.

At the upper end of the main valve shaft 7 protruding from the bearing part 6, there is a
An operating lever mounting member 24 fits into a through hole formed at one end thereof, and is fixed via a nut 25 and a washer 26. The other end of the mounting member 24 is a forked part on a plane, and a main valve element/auxiliary valve element operating lever 28 is pivotally inserted into the gap formed by this forked part via a horizontal bolt nut 27. supported. The operating lever 28 has a presser portion 28a bent upward in a substantially L shape at its tip. Reference numeral 29 denotes a gasket attached to the annular hole 20 formed at the upper end of the main valve shaft 7, and 30 represents a gasket retainer. A nut 3 is attached to the upper end of the auxiliary valve shaft 17 protruding from the main valve shaft 7.
1 is fixed, and this nut 31 and seal presser 3
A compression spring 33 is interposed between the valves 1 and 2 with a washer 32 interposed therebetween, and urges the sub-valve body 16 to be brought into close contact with the valve seat 18 at all times. The lower surface of the presser part 28a of the operating lever 28 comes into contact with the upper end surface of the sub-valve shaft 17, and by lifting the operating lever 28 using the bolt nut 27 as a fulcrum, the sub-valve shaft 17
The upper end surface of the valve body 16 is pressed against the biasing force of the spring 33 to separate the sub-valve body 16 from the valve seat 18. 34 is a plate for preventing the main valve shaft 7 from coming off; 35
~39 is Patsukin.

Next, the operation of the above embodiment will be explained.

To open the valve from the fully closed state shown in FIG.
The upper end surface of the sub-valve shaft 17 is pressed against the biasing force of the spring 33. Then, the auxiliary valve body 16 fixed to the auxiliary valve shaft 17 moves downward due to this pressure, and is separated from the valve seat 18, and the annular groove 21, They communicate through the communication hole 22, the annular groove 19, and the communication hole 23, and the pressures upstream and downstream of the main valve body 4 are approximately equal. Next, when the operating lever 28 is rotated in the horizontal direction while maintaining this communication, the main valve body 4
is gradually rotated to open the flow path, and when it is rotated approximately 90 degrees, it becomes fully open. This control lever 2
8, the main valve body 4 is rotated with a small force since there is no differential pressure acting on the main valve body. Thereafter, when the press by the holding portion 28a is released, the sub-valve shaft 17 moves upward by the spring 33, and the sub-valve body 16 comes into close contact with the valve seat 18 again.

Next, in order to close the valve from the fully open state, first lift the operating lever 28 in the same manner as described above, press the upper end surface of the sub-valve shaft 17 with the holding part 28a, and move the sub-valve body 16 onto the valve seat 18. away from the inlet 2 in the valve box 1.
After establishing communication between the side and the outlet 3 side, the operating lever 28 is rotated in the opposite direction while maintaining this communication. As a result, the main valve body 4 is gradually reversely rotated to close the flow path, and when the main valve body 4 is rotated approximately 90 degrees in the reverse direction, the inclined surface 9 formed on the outer peripheral edge of the main valve body 4 comes into close contact with the inclined surface 13 formed on the valve body valve seat 10. do. Thereafter, when the pressure by the holding portion 28a is released and the sub-valve body 16 is brought into close contact with the valve seat 18, it returns to its original fully closed state. When the main valve body 4 is closed, the hollow interior of the valve box valve seat 10 is always in communication with the inside of the valve box on the inlet port 2 side through the through hole 14, so that the adhesion between both inclined surfaces 9 and 13 is is obtained depending on the pressure on the inlet 2 side, and the sealing performance is extremely good.

Further, when the sub-valve body 16 communicates between the inlet 2 side and the outlet 3 side of the valve body 1, the communication hole 23 is formed in a straight line, and the communication holes 21, 22, 19 of the main valve shaft 7 are
Since the overall length including the length is short, the pressure loss is extremely small and the pressure equalization time is short.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional front view of a conventional device, FIG. 2 is a vertical sectional front view of an embodiment of the present invention, and FIG. 3 is a plan view of the operating lever section. 1...Valve box, 2...Inlet, 3...Outlet, 4...Main valve body, 7...Main valve stem, 10...Valve box valve seat, 16...Sub-valve body, 17...Sub-valve stem, 18...Valve seat , 19, 21... Annular groove, 22, 23... Communication hole, 24... Mounting member, 2
8... Operating lever, 28a... Presser section, 33... Compression spring.

Claims (1)

[Claims] 1. A main valve body that opens and closes the flow path is rotatably arranged in the valve body, and the inner end of a rotating main valve shaft supported by a bearing part of the valve body is fixed to this main valve body. A sub-valve shaft that can slide in the axial direction of the main valve shaft is provided at the center of the main valve shaft, and a part of the main valve shaft around the sub-valve shaft is placed on the upstream side with respect to the main valve body in the valve box. A main valve body is provided with a communication hole communicating with the main valve shaft, a sub-valve body for opening and closing the communication hole is fixed to the inner end of the sub-valve shaft, and a main valve body for rotating the main valve shaft is attached to the outer end of the main valve shaft. and an auxiliary valve element operating lever for sliding the auxiliary valve stem on the outer end of the auxiliary valve stem are provided at positions close to each other outside the valve box, and the auxiliary valve element is attached in a direction in which the auxiliary valve element is always closed. The rotary valve is provided with an urging member that applies pressure, and is characterized in that a second communication hole is bored in the main valve body for communicating the communication hole with a downstream side of the main valve body in the valve box. Pressure equalization device for rotary valves.