JPH06307554A - Flow rate control valve - Google Patents

Abstract

PURPOSE:To provide a flow rate control valve which is constituted to improve sealing ability for a control flow, prevent the occurrence of wear and the damage of a needle and a valve seat part, and prevent abrasion powder and lubricating oil from being mixed in the control flow. CONSTITUTION:A communicating hole 3 to intercommunicate first and second ports 2a and 2b, making a pair, formed in a valve housing 1 is formed in the valve housing 1 and a taper part 4b is formed. An axially moved needle 4 is mounted in the communication hole 3 and a cylindrical resilient body 5 is brought into contact with the outer peripheral surface of the needle 4 and attached to the valve housing 1. A valve seat part 6 is positioned between the ports 2a and 2b and mounted on the inner peripheral surface of the communicating hole 3. A valve opening is changed in a way that the part, positioned facing the valve seat part 6, of the cylindrical resilient body 5 is radially deformed along with axial movement of the taper part 4b formed at the needle 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique effectively applied to a flow control valve used to change the flow velocity or flow rate by giving a resistance to a fluid flow.

[0002]

2. Description of the Related Art In a flow control valve, a throttle valve is often used as a means for giving a resistance to a fluid flow to change a flow velocity and a flow rate.

This throttle valve controls the flow velocity and the passing flow rate of fluid by changing the valve opening between the taper portion of the needle and the valve seat portion of the valve housing by an adjusting screw engraved on the needle. When the flow of the fluid is shut off, the taper portion is brought into pressure contact with the valve seat portion to make the valve opening degree zero.

[0004]

As described above, in the conventional flow control valve, since the taper portion of the needle is pressed against the valve seat portion to shut off the flow of fluid, the contact portion between the two is repeatedly used. There was a problem with the sealability and durability, as it was worn and sometimes damaged.

Further, the abrasion powder generated by the pressure contact between the needle and the valve seat portion and the screwing of the adjusting screw, and the lubricating oil applied to enable the needle to move smoothly in the axial direction,
It may be mixed in the control flow flowing in the flow path, which may contaminate the control fluid or adversely affect other devices.

Therefore, an object of the present invention is to provide a technique relating to a flow control valve capable of improving the controllability of a control flow.

Another object of the present invention is to provide a technique relating to a flow control valve capable of preventing the needle and the valve seat portion from being worn or damaged and extending the life thereof.

Still another object of the present invention is to provide a technique relating to a flow control valve in which abrasion powder and lubricating oil are not mixed in the control flow.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0010]

The typical ones of the inventions disclosed in the present application will be outlined below.

That is, in the flow control valve of the present invention, the valve housing is formed with a communication hole that communicates with a port provided in a pair in the valve housing, and a taper portion is formed so that the needle that moves in the axial direction is aforesaid. The tubular elastic body, which is mounted in the communication hole and has a cylindrical shape and is made of an elastic member, is attached to the valve housing by contacting the outer peripheral surface of the needle, and the valve seat portion is positioned between the ports, so that A structure in which the valve opening degree is changed by radially deforming the portion of the cylindrical elastic body corresponding to the valve seat portion along the axial movement of the taper portion formed on the needle. belongs to.

[0012]

According to the flow rate control valve having the above-described structure, the taper portion of the needle is moved in the axial direction to change the valve opening degree between the cylindrical elastic body and the valve seat portion, The flow velocity or flow rate of the control flow is adjusted, or the tubular elastic body is pressed against the valve seat portion to shut off the flow of fluid.

At this time, since the tapered portion is not in contact with the valve seat portion by the cylindrical elastic body provided on the outer peripheral surface of the needle, the tapered portion and the valve seat portion are not worn,
A stable sealing property can be maintained. Further, since the cylindrical elastic body is brought into close contact with the valve seat portion to block the flow of the control flow, it is not necessary to strongly press the tapered portion of the needle against the valve seat portion. Further, the lubricating oil applied between the needle and the tubular elastic body is separated from the control flow in the communication hole by the tubular elastic body, and the lubricating oil is not exposed to the control flow.

[0014]

Embodiments of the present invention will now be described in more detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a sectional view showing a flow control valve which is an embodiment of the present invention. (A) shows a port closed state, (b) shows a port opened state. Shows.

First, the structure of the flow control valve of this embodiment will be described.

The flow control valve of this embodiment is embodied as a throttle valve, and the valve housing 1 of this flow control valve is used.
Is the central block 1a and the left and right end blocks 1b, 1c
It is formed by and. A first port 2a and a second port 2b are formed in a pair in the central block 1a, and these ports 2a and 2b are open to a communication hole 3 formed in the central block 1a.

In the communication hole 3, an adjusting screw 4a is engraved and screwed with the end block 1c, and a needle 4 having a circular cross section which is moved in the axial direction by the screwing of the adjusting screw 4a is provided. A cylindrical elastic body 5 made of an elastic member such as rubber and having a cylindrical shape is attached to the outer peripheral surface of the needle 4. Therefore, the needle 4 is adapted to move in the axial direction within the tubular elastic body 5.

This tubular elastic body 5 has flange portions 5 at both ends.
a and 5b are formed, one flange portion 5a is sandwiched between the central block 1a and the end block 1b, and the other flange portion 5b is formed between the central block 1a and the end block 1c.
It is sandwiched between and and attached to the valve housing 1.

On the inner peripheral surface of the communication hole 3, there is formed an annular valve seat portion 6 which is located between the two ports 2a and 2b which make a pair and which is formed so as to project inward.

At the center of the needle 4, there is formed a taper portion 4b having a smaller diameter in the opposite direction of the adjusting screw 4a. Then, the needle 4 moves to the right in the drawing by the screwing of the adjusting screw 4a, so that the tapered portion 4b of the needle 4 expands the portion of the tubular elastic body 5 corresponding to the valve seat portion 6, Finally, this part is the valve seat 6
Is closely attached to.

An air vent hole 7 is formed in the end block 1b so that the needle 4 can move smoothly in the axial direction.

Next, the operation of the flow control valve of this embodiment will be described.

In FIG. 1 (a), the needle 4 moves to the leftmost position in the drawing, and a part of the cylindrical elastic body 5 whose diameter is expanded by the tapered portion 4b of the needle 4 comes into close contact with the valve seat portion 6. The state is shown.

In this state, the valve seat portion 6 is sealed by the cylindrical elastic body 5 as a sealing material, the valve opening becomes zero, and the ports 2a and 2b are closed to each other. There is.

Under this condition, when the needle 4 is moved leftward in the drawing by the screw action of the adjusting screw 4a,
As shown in FIG. 1B, the tapered portion 4 of the needle 4
b is displaced in the axial direction, the portion of the cylindrical elastic body 5 that is in close contact with the valve seat portion 6 is reduced in diameter and separated from the valve seat portion 6, the communication hole 3 is opened, and both ports 2a and 2b are mutually connected. Will be in communication with.

Then, the valve opening changes due to the change in the diameter of the cylindrical elastic body 5 separated from the valve seat portion 6, and the flow of the control flow 8 passing through the communication hole 3 at the size of the valve opening. A constant resistance is given to the flow velocity and flow rate.

As described above, in the flow control valve of the present embodiment, the cylindrical elastic body 5 is formed by moving the taper portion 4b formed on the needle 4 moving in the axial direction in the axial direction.
The portion corresponding to the valve seat portion 6 is radially deformed, that is, the diameter is expanded or reduced to change the valve opening degree, the flow velocity and flow rate of the control flow 8 are adjusted, and the flow is shut off.

At this time, since the tapered portion 4b of the needle 4 does not come into contact with the valve seat portion 6 due to the cylindrical elastic body 5 provided on the outer peripheral surface, the tapered portion 4b of the needle 4 is provided.
The valve seat portion 6 is not worn, the stable sealing property can be maintained for a long time even if it is repeatedly used, and the life of the flow control valve can be significantly improved.

Further, the taper portion 4b of the needle 4 does not need to be strongly pressed against the valve seat portion 6 in order to seal the cylindrical elastic body 5 tightly to the valve seat portion 6 to seal the control flow 8. Therefore, there is no risk of damage and the durability can be improved.

Here, in the flow control valve as shown in this embodiment, in order to smoothly move the needle 4 inside the cylindrical elastic body 5, a lubricating oil such as grease may be applied between them. desirable. Further, without applying the lubricating oil, one or both of the inner peripheral surface of the tubular elastic body 5 and the outer peripheral surface of the needle 4 may be coated with a lubricious coating film.

When the lubricating oil is applied between the needle 4 and the cylindrical elastic body 5, the lubricating oil is enclosed in the cylindrical elastic body 5 and is not exposed in the communication hole 3. Therefore, the lubricating oil does not mix into the control flow 8 and the control flow 8 can be kept clean.

(Embodiment 2) FIG. 2 is a cross-sectional view showing a flow rate control valve which is another embodiment of the present invention, in which (a) shows a control flow state and (b) shows a free flow state. ing.

The flow control valve of this embodiment is embodied as a speed control valve, and the needle 4 for changing the flow velocity and flow rate of the control flow 8 and for interrupting the flow is provided in the valve housing 1. And a check valve 10 for allowing only the free flow 9 to flow and preventing the control flow 8 from flowing.

The first of the two ports 2a, 2b formed as a pair in the central block 1a of the valve housing 1
The port 2a serves as an inflow port for the free flow 9 and the second port 2b serves as an inflow port for the control flow 8. The ports 2a and 2b are connected to the communication hole 3 in which the annular valve seat portion 6 is formed. Each is open.

A needle 4 having a circular cross section is provided in the communication hole 3. The needle 4 has an adjusting screw 4a for axially moving the needle 4, and an adjusting screw 4a.
A tapered portion 4b having a smaller diameter toward the side opposite to a is formed.

On the outer peripheral surface of the needle 4, flange portions 5a and 5b at both ends are formed on the central block 1a and the end block 1b.
The cylindrical elastic body 5 sandwiched between the needle 4 and the needle 1c is mounted by the screw action of the adjusting screw 4a.
Are configured to move in the axial direction within the cylindrical elastic body 5. The movement of the tapered portion 4b of the needle 4 expands or reduces the diameter of the portion of the cylindrical elastic body 5 corresponding to the valve seat portion 6 to change the valve opening.

A free flow passage hole 11 is formed in the central block 1a so as to open to the second port 2b which is the inflow port of the control flow 8 and the communication hole 3, and the free flow passage hole 11 is formed. Check valve 10 for allowing only free flow 9 in the middle of the flow and blocking free flow of control flow 8.
Is provided.

FIG. 2 (a) shows the control flow in which the control flow 8 is flowing in from the second port 2b, and the cylindrical elastic body 5 and the valve seat portion 6 are fixed by the tapered portion 4b of the needle 4. The distance is kept.

In this state, since the check valve 10 is closed by the control flow 8, the control flow 8 flowing in from the second port 2b passes only through the communication hole 3. The flow rate and flow rate of the control flow 8 passing through the communication hole 3 is adjusted by the valve opening degree between the cylindrical elastic body 5 and the valve seat portion 6 and flows out from the first port 2a.

FIG. 2B shows a free flow in which the free flow 9 flows from the first port 2a.
Is the valve seat 6 due to the taper 4b of the needle 4.
And a certain distance is kept.

In this state, since the check valve 10 is opened by the free flow 9, the free flow 9 flowing from the first port 2a is not limited to the communication hole 3 but the free flow passage hole 11 as well.
Will also pass through. Therefore, the first port 2a
The free flow 9 flowing in from the free flow passage hole 11 is independent of the valve opening degree between the cylindrical elastic body 5 and the valve seat portion 6 (even if the valve opening degree in this portion is zero). Through the second port 2b.

Here, also in the flow control valve of the present embodiment, as in the flow control valve of the first embodiment, the taper portion 4b of the needle 4 moves in the axial direction to cause the valve seat of the cylindrical elastic body 5 to move. The portion corresponding to the portion 6 is radially deformed to change the valve opening degree, the flow velocity and flow rate of the control flow 8 are adjusted, or the flow of the control flow 8 is shut off.

A cylindrical elastic body 5 is formed on the outer peripheral surface of the needle 4.
Since the taper portion 4b of the needle 4 and the valve seat portion 6 are not in contact with each other, the taper portion 4b and the valve seat portion 6 are not worn. Further, since the control flow 8 can be surely shut off without strongly pressing the taper portion 4b against the valve seat portion 6,
The life of the flow control valve can be significantly improved.

In order to smoothly move the needle 4 inside the cylindrical elastic body 5, even if lubricating oil such as grease is applied between them, the lubricating oil is not exposed in the communication hole 3. Therefore, both the control flow 8 and the free flow 9 can be kept clean.

Although the invention made by the present inventor has been specifically described based on the embodiments, the invention is not limited to the embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, in the above embodiment, the needle mounted in the valve housing may be made of metal or resin.

Further, the valve opening can be adjusted with respect to the rotation angle of the needle by forming the taper portion in multiple stages or forming a curved line.

[0049]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) In the flow control valve of the present invention, the axial movement of the needle causes the tapered portion formed on the needle to radially deform the portion corresponding to the valve seat portion of the tubular elastic body. As a result, the valve opening changes, and the cylindrical elastic body is brought into close contact with the valve seat to seal the valve, so that the flow of the control flow is blocked, so that the sealing performance when the control flow is blocked is greatly improved.

(2) In addition, since the control flow is blocked by the cylindrical elastic body being in close contact with the valve seat portion, the tapered portion of the needle is not brought into contact with the valve seat portion. It Therefore, the taper part and valve seat part of the needle are not worn, and the stable sealing property can be maintained for a long time even if it is repeatedly used, and the life of the flow control valve can be greatly improved. Become.

(3) Similarly, since the tubular elastic body is brought into close contact with the valve seat portion to block the flow of the control flow, it is not necessary to strongly press the tapered portion of the needle against the valve seat portion. Therefore, there is no possibility that the valve seat portion of the flow control valve will be damaged, and the durability can be improved.

(4) Since the outer peripheral surface of the needle is covered with the cylindrical elastic body, the lubricating oil for smoothing the sliding of the needle is enclosed in the cylindrical elastic body and is inserted into the communication hole. Not only is it not exposed, the smooth movement of the needle is maintained for a long period of time, and the fluid can be kept clean without the lubricating oil, abrasion powder, etc. being mixed into the control flow.

(5) Further, since the lubricating oil for smoothing the sliding of the needle is not enclosed in the cylindrical elastic body and is not exposed in the communication hole, sufficient lubricating oil can be supplied. The life of the flow control valve can be greatly improved.

(6) Then, it is not necessary to dispose a large number of sealing members such as O-rings for maintaining the airtightness, and the number of parts is reduced to obtain a flow rate control valve which can be easily manufactured. Not only is it possible to simplify the shape of the parts, but also to reduce the manufacturing cost.

[Brief description of drawings]

FIG. 1A is a sectional view showing a state in which a port of a flow control valve according to a first embodiment of the present invention is closed, and FIG. 1B is a sectional view showing a state in which the port is opened.

FIG. 2A is a sectional view showing a control flow state of a flow control valve according to a second embodiment of the present invention, and FIG. 2B is a sectional view showing a free flow state.

[Explanation of symbols]

 1 Valve housing 1a Central block 1b End block 1c End block 2a 1st port 2b 2nd port 3 Communication hole 4 Needle 4a Adjustment screw 4b Tapered part 5 Cylindrical elastic body 5a Flange part 5b Flange part 6 Valve seat part 7 Air Vent hole 8 Control flow 9 Free flow 10 Check valve 11 Free flow communication hole

Claims (3)

[Claims] 1. A communication hole for communicating with a port provided in a pair on the valve housing is formed in the valve housing, and a needle having a taper portion and axially movable is mounted in the communication hole. A cylindrical elastic body made of an elastic member, which is in contact with the outer peripheral surface of the needle, is attached to the valve housing, and a valve seat portion is located between the pair of ports to form an inner periphery of the communication hole. On the surface,
A portion of the cylindrical elastic body corresponding to the valve seat portion is deformed in a radial direction along with an axial movement of the tapered portion formed on the needle, whereby a valve opening degree is changed. Flow control valve to. 2. The flow control valve according to claim 1, wherein lubricating oil is applied between the needle and the tubular elastic body. 3. The flow control valve according to claim 1, wherein at least one of the needle and the cylindrical elastic body is coated with a lubricous coating film.