JP2010169132A - Valve element construction - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide such a valve element construction that a valve is maintained closed up to a move distance (lift) of the valve element, corresponding to a low opening degree in a conventional method by which chattering easily occurs, and the valve is opened when exceeding a distance separated from a valve seat in which chattering does not occur in the valve element. <P>SOLUTION: The valve element 10 is provided to be able to seat on and unseat from the valve seat 9 provided in one opening end of a valve port 8 communicating with a primary side flow passage 5 and a secondary side flow passage 6. The valve element 10 includes such a sliding valve 10b that the valve is maintained closed between a seating position from the valve seat 9 and a position Y separated therefrom by a predetermined distance L, while coming into slidable contact with a valve port inner wall 8a and being reciprocatably inserted into the valve port 8, and the valve is opened by being separated from the valve port 8 when exceeding the position Y. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a valve body structure that prevents so-called chattering, a phenomenon in which a valve body repeats a valve seat at a low opening degree close to closing and generates a noise.

In the pilot type pressure reducing valve disclosed in Patent Document 1, a pressure fluid passing through the pilot valve is adjusted by a balance between an adjustment spring and a secondary side pressure, a diaphragm that is displaced by the pressure fluid, and a valve rod is attached to the diaphragm. The secondary side is held in a predetermined pressure-reduced state by adjusting the opening degree of the valve body according to the balance with the valve spring that urges the valve bodies connected via the valve closing direction.
In the pressure reducing valve, a valve seat with a tapered hole is provided at the opening end on the primary side of the valve port provided so that the primary flow path and the secondary flow path communicate with each other, and the valve seat is attached to and detached from the valve seat. The valve body is formed in a plug shape in which a seating portion with the valve seat is formed in a tapered shape.
Therefore, when the valve body is close to closing, the distance between the seating part and the valve seat in the valve body is very small, and the fluid passage is extremely narrowed here. It is easy to induce.

Japanese Patent Laid-Open No. 11-110051

Chattering occurs not only in the pressure reducing valve as described above but also in a relief valve, a check valve, and the like, both of which occur at a low opening degree close to the valve closing.
Therefore, in the present invention, until the valve element travel distance (lift) corresponding to a low opening degree, in which chattering is likely to occur in the related art, the valve element is maintained in the closed state, and the separation distance from the valve seat where the valve element cannot cause chattering. It aims at providing the valve body structure comprised so that it may open when it exceeds.

In view of the above problems, the valve body structure of the present invention is a valve body that is detachably provided on a valve seat provided at one opening end of a valve port that communicates with a primary side flow path and a secondary side flow path. The valve body is inserted into the valve port so as to be able to reciprocate while sliding on the inner wall of the valve port from the seating position with the valve seat to a position separated from the valve seat by a predetermined distance. A slip valve portion is provided which opens from the valve opening when the separation position is exceeded.
Further, the sliding valve portion may be provided with a support ring that guides the valve body by always slidingly contacting the inner wall of the valve port through a plurality of fluid insertion ports provided in the circumferential direction so as to communicate with the valve port.

  In short, the valve body according to the present invention is inserted into the valve port so as to be able to reciprocate while sliding on the inner wall of the valve port from the seating position with the valve seat to a position separated by a predetermined distance. By holding and providing a slip valve portion that opens away from the valve opening when the separation position is exceeded, at the initial valve opening or just before closing, the seat portion with the valve seat in the valve body, and the valve seat The distance between the valve seat and the valve seat is not so close that the seating portion of the valve body can repeatedly contact the valve seat violently, so chattering does not occur.

  Since the slide valve portion is provided with a support ring that guides the valve body by always slidingly contacting the inner wall of the valve port through a plurality of fluid insertion ports provided in the circumferential direction so as to communicate with the valve port. Even if the valve body is opened, it is not touched by vibration or the like, and the operation of the valve body can be stably supported at all times.

It is a longitudinal section of a pilot type pressure reducing valve equipped with a valve body structure concerning the present invention. It is a principal part expanded sectional view at the time of valve closing. It is a principal part expanded sectional view at the time of the valve opening initial stage or just before valve closing. It is a principal part expanded sectional view at the time of a full open.

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view of a pilot pressure reducing valve equipped with a valve body structure according to the present invention.
The valve box 2 of the pressure reducing valve 1 has an inlet 3 and an outlet 4 for pressure fluid on the left and right sides, a primary flow path 5 communicating with the inlet 3 inside, and a secondary flow path 6 communicating with the outlet 3. And are provided.

In the center of the valve box 2, a partition wall 7 in which a primary side channel 5 and a secondary side channel 6 are vertically divided is provided, and a valve port 8 communicating with both the channels 5, 6 is provided in the center of the partition wall 7. Opened.
At the opening end on the primary side of the valve port 8, a tapered valve seat 9 having a diameter gradually reduced toward the secondary side is provided, and the seating portion 10a with the valve seat 9 is tapered (conical frustum). A plug-shaped valve element 10 formed in the shape of a valve is provided on the valve seat 9 so as to be freely attached and detached.

The valve body 10 reciprocates while sliding on the inner wall 8a of the valve port from a seating position of the seating portion 10a with the valve seat 9 (see FIG. 2) to a position Y (see FIG. 3) separated by a predetermined distance L. A substantially disc-shaped slip valve portion 10b is provided which is inserted into the valve port 8 so as to be movable and keeps the valve closed, and is separated from the valve port 8 to open when the separation position Y is exceeded.
The sliding valve portion 10b has a height t corresponding to the distance L, and this distance L is the distance traveled by the valve body 10 separated from the valve seat 9 to such an extent that the valve body 10 (sitting portion 10a) cannot cause chattering. It is set to correspond to.
In this way, by providing the sliding valve portion 10b, chattering is likely to occur (conventionally corresponding to a low opening degree close to valve closing) until the moving distance (lift) of the valve body 10 is increased. When the valve body 10 is closed when the valve body 10 is inserted and the valve body 10 exceeds the distance from the valve seat 9 where chattering cannot occur (see FIG. 3), the sliding valve portion 10b No valve chattering occurs because the valve is opened from 8.

The sliding valve portion 10b is connected to a plurality of fluid insertion ports 11 provided in the circumferential direction of the sliding valve portion 10b so as to communicate with the valve port 8 while the valve body 10 is opened (see FIGS. 3 and 4). A support ring 10c for always guiding the valve body 10 by slidingly contacting the inner wall 8a of the valve port is provided.
As shown in the present embodiment, the valve body 10 is provided with a substantially disc-shaped slip valve portion 10b at the end on the seating portion 10a (lower end) side, and a fluid is continuously provided below the slip valve portion 10b. It is more desirable to provide the insertion port 11 and the support ring 10c, because even if the valve element 10 is opened by the support ring 10c, the valve element 10 is not touched by vibrations and the valve operation of the valve element 10 is always stabilized. However, since the chattering can be prevented only by providing the sliding valve portion 10b in the valve body 10, the fluid insertion port 11 and the support ring 10c are not necessarily provided.

A diaphragm casing 13 in which an inner space is partitioned vertically by a diaphragm 12 is provided at the lower part of the valve box 2.
In the center of the upper part of the diaphragm casing 13, a valve rod 14 whose upper end is connected to the end of the valve body 10 through the valve port 8 through the valve port 8 is inserted and installed on the upper surface of the diaphragm 12. The lower end of the valve stem 14 is brought into contact with the diaphragm 12 through the diaphragm retainer 15, and the diaphragm 12 and the valve body 10 are connected via the valve stem 14.
The upper space defined by the diaphragm 12 in the diaphragm casing 13 communicates with the secondary flow path 6 through a communication hole 16 penetrating in the upper part, and the lower space of the diaphragm 12 forms a pressure chamber 17.

  The upper part of the valve box 2 is provided with a communication port with the primary flow path 5 at the center thereof, and the lower end port of the pilot valve box 18 installed at the upper end of the valve box 2 through the communication port and the primary flow path 5 The valve spring 20 is compressed and interposed between the ring-shaped spring receiver 19 attached to the lower end and the spring seat 10d formed on the upper part of the valve body 10, thereby closing the valve body 10 in the valve closing direction. Is energized.

The pilot valve box 18 is provided with a pilot pressure chamber 21 in the center thereof, and urges the pilot pressure chamber 21 and the primary flow path 5 communicating with the lower end through a pilot valve spring 22 in the valve closing direction. The pilot valve 23 is provided to communicate or block.
The pilot pressure chamber 21 communicates with the pressure chamber 17 via a conduit 24, and a branch conduit 24 a of the conduit 24 is connected to an orifice 25 provided in the secondary side flow path 6 to cause the pilot pressure chamber 21 to flow in the secondary side flow. It communicates with the road 6.

The valve rod 23a of the pilot valve 23 protrudes slidably into a space 26 defined in the upper part of the pilot pressure chamber 21, and this space 26 is covered on the pilot valve box 18 via a pilot diaphragm 27. It is partitioned from the internal space of the spring cover 28 and forms a pilot diaphragm chamber 26.
In the internal space of the spring cover 28, an adjustment spring 30 having an elastic force adjustable by an adjustment screw 29 protruding from the upper part of the spring cover 28 is urged to the upper surface of the pilot diaphragm 27, and the valve rod 23a is urged through the pilot diaphragm 27. The projecting end portion is configured to receive the elastic force of the adjusting spring 30.
The pilot diaphragm chamber 26 communicates with the secondary flow path 6 through a detection tube 31 connected to the outlet 4 so that the pilot diaphragm 27 is displaced by the secondary pressure.

In the pressure reducing valve 1 configured as described above, the valve body 10 is closed by the valve spring 20 and the pilot valve 23 is closed by the pilot valve spring 22 when the adjustment spring 30 is not loaded.
When the high pressure fluid flows into the primary side flow path 5, the primary side pressure is applied to the valve body 10 and the back of the pilot valve 23.
In this state, the adjustment spring 30 is compressed by the adjustment screw 29, and the valve rod 23a is pressed through the pilot diaphragm 27 by the elastic force to open the pilot valve 23.
As a result, the pressure fluid in the primary channel 5 flows from the pilot pressure chamber 21 via the conduit 24 into the pressure chamber 17 and also flows into the secondary channel 6 via the branch conduit 24 a and the orifice 25.

When the flow rate through the pilot pressure chamber 21 is greater than the flow rate through the orifice 25, the operating pressure in the pressure chamber 17 rises and overcomes the pressure on the back of the valve body 10 and the elastic force of the valve spring 20 to push the valve body 10. The pressure fluid starts to flow from the primary channel 5 to the secondary channel 6.
Further, the pressure fluid flowing into the secondary side flow path 6 is guided from the detection pipe 31 to the pilot diaphragm chamber 26.

The pilot diaphragm 27 receives the secondary side pressure, balances with the adjustment spring 30, and the pressure acting on the pilot diaphragm 27 due to the increase or decrease of the secondary side pressure and the adjustment spring 30 work to increase or decrease the opening by the pilot valve 23, The amount of inflow into the pressure chamber 17 is changed to control the opening degree of the valve body 10 so that the secondary side has an appropriate pressure.
When there is no load on the secondary side, the pressure in the pilot diaphragm chamber 26 rises and the pilot valve 23 closes, so that the operating pressure in the pressure chamber 17 escapes to the secondary side flow path 6 through the orifice 25. The valve body 10 is pushed by the valve spring 20 and closes.

The valve opening / closing operation of the valve body will be described in detail. In the closed state, the seat portion 10a of the valve body 10 is seated on the valve seat 9, thereby closing the valve port 8 as shown in FIG.
At this time, the sliding valve portion 10b, the fluid insertion port 11 and the support ring 10c provided at the lower part of the valve body 10 are in the inserted state in the valve port 8, and the fluid insertion port 11 is closed by the valve port inner wall 8a. .
And even if the valve body 10 moves in the valve opening direction from the seating position of the seating portion 10a shown in FIG. 2 to the valve seat 9, the seating portion 10a is in the range from the seating position to the position Y separated by the distance L. Although the valve seat 9 is disengaged, the sliding valve portion 10b is in sliding contact with the valve port inner wall 8a to close the valve port 8, so that the valve closed state is maintained.

When the valve body 10 moving in the valve opening direction exceeds the separation position Y, the slip valve portion 10b is detached from the valve port 8, and the fluid insertion port 11 enters the primary side flow path 5 from the primary side opening of the valve port 8. When it appears, the valve is opened, and the primary side flow path 5 communicates with the secondary side flow path 6 through the fluid insertion port 11 and the valve port 8.
In the initial stage of valve opening shown in FIG. 3 or just before the valve is closed, the distance between the seating portion 10a of the valve body 10 and the valve seat 9 can be reliably increased as compared with the prior art, and the seating portion 10a of the valve body 10 is Since the distance from the valve seat 9 is not so close that the contact can be repeated violently, chattering does not occur.
As shown in FIGS. 2 to 4, during the opening / closing operation of the valve body 10, the support ring 10c is always present in the valve port 8 and slidably contacts the inner wall 8a to guide the valve body 10. Even if the valve element 10 is opened, it is not touched by vibrations or the like, and the on-off valve operation of the valve element 10 is always stably supported.

In this embodiment, the valve body 10 according to the present invention is provided in the pressure reducing valve 1. However, the present invention can also be applied as a valve body in a valve such as a relief valve or a check valve.
In the present embodiment, the valve seat 9 is formed in a tapered hole shape, and the seating portion 10a of the valve body 10 is formed in a tapered shape so as to correspond to the valve seat 9. However, the present invention is limited to this method. For example, a flat valve seat 9 may be provided at one opening end of the valve port 8, and a flat seat portion 10 a parallel to the valve seat 9 may be provided in the valve body 10.

5 Primary side flow path 6 Secondary side flow path 8 Valve port
8a Valve inner wall 9 Valve seat
10 Disc
10b Slide valve
10c Support ring
11 Fluid inlet L Distance Y Separated position

Claims (2)

  A valve body provided detachably on a valve seat provided at one opening end of a valve port communicating with the primary side flow path and the secondary side flow path, the valve body including the valve seat and From the seating position to a position separated by a predetermined distance, it is inserted into the valve port in a reciprocating manner while sliding on the inner wall of the valve port to maintain the valve closed state. A valve body structure characterized by providing a sliding valve portion for opening the valve.   The slide valve portion is provided with a support ring that guides the valve body by always slidingly contacting the inner wall of the valve port through a plurality of fluid insertion ports provided in the circumferential direction so as to communicate with the valve port. Item 1. The valve body structure according to Item 1.

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