JPS60237273A - Pressure equalizing device for rotary valve - Google Patents

Abstract

PURPOSE:To effect the pressure equalization in upstream and downstream as well as the opening and closing of a main valve body by the rotating operation of a valve shaft only by driving a sub valve body through an operating member screwed unpivotally to a male screw provided at one end of the valve shaft. CONSTITUTION:When the valve shaft 10 is turned through a handle, a nut 40, screwed to the male screw section 23 of the valve shaft 10, is regulated in the pivoting thereof, therefore, is moved down to push the sub valve body 33 against a spring 37. According to this operation, the inflow port 2 side and the outflow port 3 side in a valve box 1 are communicated through a communicating hole 47 and the pressures in the upstream and downstream of the main valve body 4 are equalized substantially. When the valve shaft 10 is turned further, a key 11 abuts against the other end 45b of a key groove 45 and the valve shaft 10 is engaged with the main valve body 4, as a result, the main valve body 4 is turned gradually and a flow path may be opened.

Description

[Detailed Description of the Invention] (Subject of the Invention) The invention relates to a pressure equalizing device for a rotary valve, and more specifically, to a pressure equalizing device for a rotary valve. Related to a Device for Reducing Rotational Torque Required for a Valve Stem (Prior Art) An example of a conventional device of this type is shown in FIG. This is done by providing a pipe 107 in contact with the valve box 101 of the rotary valve, and when the main valve body 109 opens and closes, the valve 106 is opened to almost equalize the pressure upstream and downstream of the main valve body 109, and then the rotation torque is increased. Rotating the reduced valve stem 111,
It opens and closes the main valve body 109. 113 is a valve seat member, 114 is a holding member for the valve seat member, and 115 is a support spring.

However, when opening and closing the main valve body 109, the valve 106 of the pipe 107 must be opened before the valve shaft 111 is rotated, resulting in a two-step operation, which is complicated. There are problems such as the need for external piping 107 and extra space for it.

(Problem) Therefore, the technical problem of this invention is to make it possible to equalize the pressure upstream and downstream of the main valve body and open and close the main valve body with a simple one-step operation without requiring external piping. .

(Technical means) The technical means taken to solve the above technical problem are:
A communication hole is bored in the main valve body so that the upstream and downstream sides communicate with the main valve body in the valve box, and a sub-valve body that opens and closes this communication hole is movable in the axial direction at one end of the valve shaft. A biasing member that is inserted into the valve body and biases the sub-valve body in a direction to permanently close the communication hole is provided, and an actuating member that moves the sub-valve body against the biasing force of the bias member is provided on the valve shaft. The main valve body is non-rotatably screwed into a male thread provided at one end of the main valve body, and the main valve body is adapted to engage with the valve shaft after the valve shaft has rotated by a predetermined angle.

(Function) When the valve stem is rotated in the fully closed state, the actuating member screwed into the male thread of the valve stem moves toward the sub-valve element, and presses the sub-valve element against the biasing force of the biasing member.

Due to this suppression, the sub-valve body moves to open the communication hole, and the inlet side and the outlet side in the valve box communicate with each other, and the pressures upstream and downstream of the main valve body become approximately equal.

When the valve shaft is further rotated, the main valve body engages with the valve shaft and is gradually rotated to open the flow path and become fully open. The rotational torque of the valve stem accompanying the opening of the main valve element is reduced because the auxiliary valve element opens before the main valve element is opened, so that there is almost no differential pressure acting on the main valve element. Therefore, the main valve body is rotated with a small force.

To change the fully open state to the fully closed state again, rotate the valve shaft in the opposite direction. As a result, the main valve body, while engaged with the valve stem, is gradually rotated in the opposite direction to close the flow path and reach a fully closed state. Thereafter, the main valve body does not move and only the valve shaft rotates in the opposite direction by a predetermined angle. During this time, the actuating member moves in the opposite direction, and as the actuating member moves, the sub-valve body moves in the same direction by the biasing force of the biasing member to close the communication hole. As mentioned above, since the pressure can be equalized upstream and downstream of the main valve body and the main valve body can be opened and closed simply by rotating the valve shaft, the installation space can be minimized since no external piping is required.

(Special effect) As mentioned above, the main valve body can be opened and closed easily with a one-stage operation of only rotating the valve shaft with reduced rotational torque when opening the valve, so it is possible to easily open and close the main valve body with a one-stage operation, which requires only the rotation of the valve shaft with reduced rotational torque when opening the valve. Since there is no need to perform operations sequentially and accurately, there is no possibility of malfunction, and therefore safe and reliable operation can be expected.

In addition, since the sub-valve body that closes the communication hole moves while being guided by the valve shaft into which it is inserted, stable movement is possible, and the structure is simple because no other guide member is required. In addition, since the actuating member that presses the sub-valve element is configured to move in the axial direction without rotation, the sub-valve element can smoothly contact the valve seat without rotating via the biasing member when closing the communication hole. Therefore, the valve seat is not twisted or damaged and can be used for a long period of time.

(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 box 1, which is integrally connected to the upper and lower ends thereof and has fC grooves 5, 5a;
The key 1111t is engaged with and fitted to the lower part of the rotary valve shaft 10 which is vertically supported by the bearing part 6 on the upper wall of the valve box via the bushing 8, and the joss part 5a is fitted to the bottom wall of the valve case. It is rotatably fitted into the upper end of a support bin 13 which is vertically supported and pivoted facing IO. The outer peripheral edge of the main valve body 4 is formed into a spherical seat 14 .

An annular valve seat member 15 is disposed on the inner wall of the valve box on the side of the outflow port 3 from the main valve body 4, with its side wall on the inlet port 2 side abutting against a step 16 formed on the inner wall of the valve box. Main valve body 4 of member 15
The outer peripheral surface of the side is formed into a spherical seat 18 that comes into close contact with the spherical seat 14 of the main valve body when the valve is closed. A holding member 20 in the shape of a short hollow cylinder is attached to the inner wall of the valve box on the side of the outflow port 3 from the valve seat member 15.
The valve seat member 15 is screw-fitted from the outlet 3 side, and is fixed in the valve box 1 by pressing the side wall of the valve seat member 15 on the outlet 3 side with the end face of the tip.

A portion of the lower portion of the valve shaft 10 below the key 11 is formed into a small diameter portion 22 . The small diameter portion 22 is further formed downward by a male thread portion 23, a guiding straight portion 24, and a stepped portion 25, and becomes a male thread portion 26 with a smaller diameter.
A space between the upper outer periphery of the valve shaft 2 and the shaft hole 28 into which the valve shaft 10 is fitted is formed into an annular hole 30 whose lower end is open.

A sub-valve body 33 having a flange portion 32 having a larger diameter than the annular hole 30 is fitted into the straight portion 24 so as to be movable up and down. A compression spring 37 is interposed between the flange portion 32 of the sub-valve body 33 and a flat washer 36 which is in contact with the stepped portion 25 of the male threaded portion 26 and fixed with a nut 34. The valve seat 38 for the sub-valve element is in close contact with a flat ring-shaped valve seat 38 fixed to the lower end surface of the screw part 5 by always being biased upward. Also,
A grooved nut 40 is screwed into the male threaded portion 23. A bottomed vertical groove 41 is formed on the outer peripheral surface of the nut 40, and an I-seat 43 is screwed into the screw hole 42 that penetrates the screw part 5 laterally, as shown in FIG. The tip portions are engaged, making the nut 40 unrotatable.

The keyway 45 on the side of the screw part 5 that engages with the key 11 is the fifth
As shown in the figure, it is formed with play in the circumferential direction.

Reference numeral 47 denotes a communication hole formed to be inclined from the piston portion 5 toward the main valve body 4. One end of this communication hole 47 opens into the annular hole 30, and the other end opens into the front wall of the main valve body 4. However, when the sub-valve body 33 is opened when the main valve body 4 is closed, the inside of the valve box on the inlet z side and the inside of the valve box on the outflow port 3 side are connected to the annular hole 30 and the communication hole 4.
It is designed to communicate via 7.

The upper end of the valve shaft 10 protruding from the bushing 8 has a square head 1
0 m, and the valve shaft 10 is rotated by fitting an operation handle (not shown) into the head 10a.

51 is an annular flange provided on the valve shaft lO, 52 is a retaining ring for preventing the bushing 8 from being pulled out, and 53 to 59 are 0s/g.

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

To open the valve from the fully closed state shown in Figures 2 and 3, the head 10
When the operating handle is fitted to M and the valve shaft 10 is rotated through this handle, the nut 40 screwed onto the male threaded portion 23 of the valve shaft 10 restricts its rotation due to the I seat 43. 3, the sub-valve body 33 is moved downward by the spring 37.
Press against. Due to the pressure, the sub-valve body 33 moves downward along the straight portion 24 and separates from the valve seat 38, forming a small gap between the sub-valve body 33 and the valve seat 38. Therefore, the small gap between the inlet 2 side and the outlet 3 side in the valve @1
They communicate through the annular hole 30 and the communication hole 47, and the pressure in the first stream above the main valve body 4 is approximately equal. The rotation angle α of the valve shaft lO until the outflow inlets 2 and 3 sides in the valve body 1 are brought into communication by the downward movement of the sub-valve body 33 is determined by the key 11 as shown in FIG.
is within the play section from one end 45m of the keyway 45 to the other end 45b, and therefore the valve shaft 10 and the main valve body 4 are
There is no engagement, and there is no rotation of the main valve body 4.

When the valve shaft 10 is further rotated, the key 11 comes into contact with the other end 45b of the keyway 45, and the valve shaft 10 and the main valve body 4 are engaged, so that the main valve body 4 is gradually rotated to open the flow path. However, when it rotates approximately 90 degrees, it becomes fully open. This main valve body 4
When rotating the valve shaft 10 when rotating the main valve body 4, the auxiliary valve body 33 opens the communication hole 47 by rotating the valve shaft 10 by the α angle and acts on the main valve body 4. In order to almost eliminate the differential pressure, the rotational force of the valve shaft 10 accompanying the subsequent rotation of the main valve body 40 is reduced, and the main valve body 4 is rotated with a small force.

Next, to change the state from fully open to fully closed, the valve shaft 10 is rotated in the opposite direction. At this time, the main valve body 4 is eccentric, and upstream pressure is acting on the main valve body 4, and it is about to rotate in the closing direction. Therefore, when the valve shaft 10 is rotated in the opposite direction, the key 11
The main valve body 4 is formed on the outer peripheral edge of the main valve body 4 while the main valve body 4 remains in contact with the other end 45b of the keyway 45, that is, in a position where the valve shaft 10 and the lance part 5 have moved by an angle of β without relative rotation. The spherical seat 14 contacts the spherical seat 18 of the valve seat member 15 and closes the flow path. After that, the main valve body 4 no longer moves, and the valve stem 10
will move by α angle. That is, the key 11 comes into contact with one end 45m from the other end 45b of the keyway 45, and during this time the nut 40 moves upward, and as the nut 40 moves upward, the sub-valve body 33 is moved by the biasing force of the spring 37. It moves upward and comes into close contact with the valve seat 38, completely blocking communication between the upstream and downstream sides. In this case, since the sub-valve body 33 is closed after the main valve body 4 is closed, it is possible to minimize wear and the like on the valve seats 14 and 18 when the main valve body 4 is closed, and also to prevent water hammer. Prevented. In FIG. 5, β indicates the rotation angle of the valve shaft 10 required to fully open or close the main valve body 4.

It should be noted that the shape of the main valve body 4 and the arrangement of the communication hole 47 in the above-mentioned embodiments are merely examples, and it goes without saying that other shapes and arrangements having similar functions may be used.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional front view of a conventional example, Fig. 2 is a longitudinal sectional front view of an embodiment of the present invention, Fig. 3 is an enlarged sectional view of the main parts of the same, and Fig. 4
The figure is a partially omitted cross-sectional view taken along the W-TV line in Figure 3,
FIG. 5 is a sectional view taken along the line -V in FIG. 3. 1...Valve box 2...Inflow port 3...Outlet port 4...Main valve body 5.5a...Jisu part 6...Bearing part 10...Valve stem 11...Key 15...Valve seat member 20...Press member 22...Small diameter part 23...Male thread part 24...Straight part 2
6...Threaded portion 28...Shaft hole 30...Annular hole 33...Sub-valve body 34...Nut 36...Flat washer 37...Compression spring 38...Valve seat 4o. ...Grooved nut 41...Vertical groove 43...Gilt 45...Keyway 47...Communication hole Patent applicant Kurimoto Iron Works Co., Ltd. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1. A main valve body that opens and closes the flow path is rotatably disposed inside the valve box, one end of the rotary valve shaft is fitted to the main valve body, and the other end of the valve shaft is placed outside the valve box. In the rotary valve in which the protruding part is provided with a rotary operation part, the main valve body is provided with a communication hole through which the upstream side and the downstream side communicate with the main valve body in the valve box. A sub-valve body for opening and closing is fitted into one end of the valve shaft so as to be movable in the axial direction, and a biasing member is provided for biasing the sub-valve body in a direction to constantly close the communication hole, and the biasing member is provided. An actuating member that moves the sub-valve body against the urging force of is unrotatably screwed into a male thread provided at one end of the valve shaft,
A pressure equalizing device for a rotary valve, wherein the main valve body is adapted to be engaged with the valve shaft after the valve shaft has rotated by a predetermined angle.