JPS602378Y2 - flow control valve - Google Patents

Description

[Detailed description of the invention] For example, to control the operating speed of an air cylinder, etc.
A compressed air flow rate control valve is used, but conventional control valves require O-rings and the like to prevent fluid leakage in the adjustment section, which has the drawback of being complex, large and expensive.

That is, FIG. 3 is a vertical cross-sectional view of a conventional flow control valve as described above, in which a fluid inlet 102 and an outlet 10 are formed in a base body 101.
3 and a shaft valve 106 is disposed therebetween, and a small hole 107 and a passage 108 allow the inlet 10 to be
2 and the outlet 103 are connected, and a needle valve 109 is fitted into the small hole 107.

The needle valve 109 is attached to the tip of the adjusting screw 110 to adjust the flow rate of the fluid flowing from the inlet 102 to the outlet 103, but in order to prevent the fluid from leaking at the threaded surface of the screw 110. , the above screw 110
A cylindrical portion 120 is provided between O and the needle valve 109.
The ring 130 is fitted.

Since the conventional device required the O-ring 130 as described above, a cylindrical sealing surface 140 with a length greater than the amount of movement of the needle valve was formed inside the base body 101, and the screw 1
10 needs to be provided with a cylindrical portion 120, etc., making the structure complicated and the base body 101 large, and the sealing surface requires high-precision finishing, which requires a long time to process and increases the cost. The price has also increased.

Therefore, the present invention provides a flow control valve that has a simple structure, can be manufactured in a small size, and can be easily finely adjusted.

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, and FIG. 2 is a side view thereof. A base body 1 is provided with an inlet 2 and an outlet 3 for gas or liquid whose flow rate is to be controlled, and these are connected as fluid channels. 4, and a conical valve seat 5 is provided on the inlet side of the passage.

Further, the base body 1 is provided with a threaded hole 6 for an adjustment screw perpendicular to the axes of the inlet and outlet, and a small hole 7 is formed which communicates with the fluid passage 4 from the bottom surface of the threaded hole 6. In addition, a fluid passage 8 is provided which directly connects the screw hole 6 and the inlet 2.

An adjustment screw 10 having a needle valve 9 at the tip is screwed into the screw hole 6, and the valve 9 is fitted into the small hole 7. A lock knob 11 is attached to the base of the adjustment screw 10. They are screwed together, and a washer 12 is inserted between the knob and the base body 1.

Further, an annular packing 13 made of an elastic material such as rubber is baked onto the inner circumferential portion of the washer 12, which tightly fits into the adjustment screw 10.

Furthermore, an end cap 14 is fitted and fixed to the inlet 2, and a shuttle valve 16 is disposed between the nozzle 15 formed in this cap and the valve seat 5, and the valve is held in place by a spring 17. A hole 18 is formed in the side surface of the nozzle 15 while being pressed against the valve seat 5, and a mounting hole 19 is provided in the base body 1.

In the above control valve, when the inlet 2 is connected to a compressed air source, the shuttle valve 16 is pressed against the valve seat 5 by the pressure of the compressed air and the elasticity of the spring 17, and the inlet and outlet 3
This prevents them from being directly connected via the passage 4.

Therefore, the air sent into the inlet 2 passes through the passage 8 and the threaded hole 6 of the adjusting screw, and is then sent out from the outlet 3 through the gap between the small hole 7 and the needle valve 9.

When the knob 11 is loosened and the adjusting screw 10 is rotated, the above-mentioned gap changes, so that the flow rate of air sent from the outlet 3 to the air cylinder or the like is controlled.

After making the adjustment in this way, by tightening the knob 11, the rotation of the adjustment screw 10 can be prevented and locked, and the annular packing 13 attached to the inner circumference of the washer is compressed to make the adjustment. Since it is in close contact with the circumferential surface of the screw 10, leakage of compressed air can be reliably prevented.

Further, when the inlet 2 is opened to the atmosphere, the spring 17 is compressed by the pressure of compressed air sent into the outlet 3 from an air cylinder or the like, and the shuttle valve 16 is separated from the valve seat 5.

Therefore, the air sent to the outlet 3 is further transferred to the shuttle valve 1.
6 is pushed open and the liquid is discharged from the inlet 2.

As described above, the present invention provides a fluid inlet and an outlet in the base body, and includes a shuttle valve therebetween that allows fluid to flow backwards and prevents the fluid from flowing in the forward direction. In a flow control valve, a needle valve attached to the tip of the adjusting screw is fitted into a small hole connecting the screwing hole, and a fluid passage connecting the screwing hole and the inlet is provided. It has a structure in which a locking knob is screwed onto the base and a washer provided with an elastic packing that tightly fits over the adjustment screw is inserted between the knob and the base body.

In this way, the present invention uses a washer with an elastic packing on the inner periphery to prevent fluid leakage at the adjustment screw, so it is possible to eliminate the cylindrical sealing surface that requires high-precision machining inside the base. There is no need to form a control valve, the structure is simple and compact, and the control valve can be manufactured at low cost.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention, FIG. 2 is a side view of the control valve of FIG. 1, and FIG. 3 is a longitudinal sectional view of a conventional flow control valve. In the figure, 1 is the base, 2 is the inlet, 3 is the outlet, and 4
1 is a fluid passage, 5 is a valve seat, 6 is an adjustment screw threading hole, 7 is a small hole, 8 is a fluid passage, 9 is a needle valve, 10 is an adjustment screw, 1
1 is a lock knob, 12 is a washer, 13 is a packing, 14
is an end cap, 15 is a nozzle, 16 is a shuttle valve,
17 is a spring, 18 is a hole, and 19 is a mounting hole.

Claims (1)

[Scope of utility model registration request] A fluid inlet and an outlet are provided in the base body, and a shuttle valve is provided therebetween to allow fluid to flow backward and prevent forward flow, and a small body is provided to connect the outlet and the threaded hole of the flow rate adjustment screw. In a flow rate control valve in which a needle valve attached to the tip of the adjusting screw is fitted into the hole and a fluid passage is provided to connect the screwing hole and the inlet, a locking knob is screwed into the base of the adjusting screw. 1. A flow control valve characterized in that a washer provided with an elastic gasket that tightly fits into the adjustment screw is inserted between the knob and the base body.