JPH0416668B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a directional control valve used when controlling a cylinder or the like by switching a flow path of air pressure, oil pressure, or the like.

[Prior Art] Generally, a so-called spool valve is known as a directional control valve used for controlling the operation of pneumatic control equipment or hydraulic control equipment such as a cylinder.

That is, a ring-shaped gasket is attached to an annular groove provided on the spool shaft that is inserted into the valve body.
A supply port that is opened at different positions in the axial direction of the inner circumference of the valve body by sliding the outer circumference of the packing onto a valve seat protruding from the inner circumference of the valve body and displacing the spool shaft in the axial direction. Communication between the valve body and the plurality of discharge ports is selectively performed through a gap between the spool shaft and the valve body.

[Prior Art] However, the conventional spool valve as described above requires a drive mechanism to displace the spool shaft in the axial direction, resulting in a complicated structure. In addition, a gasket protruding from the outer circumference of the spool shaft and a valve seat protruding from the inner circumference of the valve body form a gap between the spool shaft and the inner circumference of the valve body, and connect the supply port and the discharge port. There is also the problem that the resistance of the communicating flow path becomes relatively large, making it difficult to obtain a large discharge flow rate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a directional control valve whose structure can be simplified and downsized, and which can relatively increase the flow rate of controlled fluid.

[Means for Solving the Problems] The present invention provides a directional control valve that is provided with a predetermined gap between a main body in which fluid passages are opened at different positions in the axial direction on the inner circumference of a cylinder portion, and a cylinder portion,
An annular groove is formed on the outer periphery, and the shaft is made of an elastic body, and a pressurized port is formed inside to communicate with the groove. The structure includes an annular valve body that closes the gap by being expanded by fluid pressure applied to the groove.

[Operation] According to the above-described means, the fluid passage can be opened and closed by expanding and contracting the annular valve body in the radial direction depending on the presence or absence of fluid pressure applied to the pressurized port. This eliminates the need for a complicated mechanism for displacing the part in the axial direction, resulting in a simpler and more compact structure.At the same time, the elasticity of the valve body itself allows the valve body to be drawn into the groove when communicating with the fluid passage. Since there are no protrusions that increase flow resistance between the outer periphery of the shaft portion and the inner periphery of the cylinder portion of the main body, the flow rate of the fluid to be controlled can be made relatively large.

Embodiment 1 FIG. 1 is a schematic sectional view showing the main parts of a directional control valve that is an embodiment of the present invention.

A cylinder portion 2 is formed in the main body 1, and a shaft portion 3 is provided in the cylinder portion 2 with a predetermined gap 4 therebetween.

An annular groove 5 is formed on the outer periphery of the shaft 3, and an annular valve body 6 made of an elastic body is mounted in the groove 5.

The annular valve body 6 has an inner diameter and an outer diameter in a free state that are approximately equal to the outer diameter of the groove portion 5 and the outer diameter of the shaft portion 3, respectively, and is housed inside the groove portion 5.

Further, the valve body 6 is provided on the inner circumference of the cylinder portion 2.
The inlet passage 7 (fluid passage) and the outlet passage 8 (fluid passage) at axially different positions through the device position of
are opened, and both are connected to the cylinder 2 and the shaft portion 3.
It is communicated through a gap 4 between the two.

Furthermore, a pressurized port 9 that communicates with the groove 5 is formed inside the shaft 3, and by applying fluid pressure to the groove 5 from the outside, the By expanding the annular valve body 6 in the radial direction and bringing it into close contact with the inner circumference of the cylinder portion 2 of the main body 1, the gap 4 between the cylinder portion 2 and the shaft portion 3 is closed, and the inlet flow path 7 and the outlet flow path 8 are closed. The structure is such that both are blocked.

In this case, the pressurized port 9 is connected to the pilot valve 10.
The pilot valve 10 is linked with a plunger 12 displaced by a solenoid 11, and is connected to a valve spring 1.
It is configured to be opened and closed by the urging force of No. 3.

Further, the pressurized port 9 is communicated with a pilot exhaust port 14 via a pilot valve 10, and when the pressurized port 9 and the inlet flow path 7 are shut off by the pilot valve 10, the pressurized port 9 and a pilot exhaust port 14 are communicated with each other, and the fluid inside the pressurized port 9 is discharged to the outside.

The operation of this embodiment will be explained below.

First, compressed air pressure, for example, is applied to the inlet channel 7 from a fluid pressure source (not shown), and the outlet channel 8 is connected to a cylinder device (not shown) operated by the compressed air. .

First, when the solenoid 11 is de-energized, the pilot valve 10 is opened by the biasing force of the valve spring 13, and the inlet flow path 7 and the pressurized port 9 are communicated with each other, as shown in FIG. Pressurized port 9
and the pilot exhaust port 14 are shut off, and the fluid pressure applied to the inlet flow path 7 is applied to the groove 5 through the pressurized port 9, and the annular valve body 6 installed in the groove 5 is caused to act by the fluid pressure. It expands in the radial direction and comes into close contact with the inner periphery of the cylinder part 2, and the gap 4 between the cylinder part 2 and the shaft part 3 is closed, and compressed air etc. Fluid is prevented from escaping.

Next, when the solenoid 11 is energized, the pilot valve 10 which is interlocked with the plunger 12 is activated by the valve spring 1.
3, the inlet channel 7 and the pressurized port 9
At the same time, the pressurized port 9 and the pilot exhaust port 14 are communicated with each other, and the fluid pressure applied to the groove portion 5 through the pressurized port 9 is released, and the fluid is expanded by the fluid pressure and flows into the cylinder portion 2. The annular valve body 6, which was in close contact, quickly contracts and returns in the radial direction due to its own elasticity, and is in the state shown in FIG.
The closed state of the gap 4 between the cylinder portion 2 and the shaft portion 3 is released, and fluid such as compressed air acting on the inlet flow path 7 is supplied to the outlet flow path 8.

As described above, in this embodiment, the inlet flow path 7 and the outlet flow path 8 opened in the cylinder portion 2 of the main body 1 are
The annular groove portion 5 of the shaft portion 3 inserted into the cylinder portion 2 with a predetermined gap 4 is configured to communicate with and interrupt the communication with the cylinder portion 2.
This is done by expanding and contracting an annular valve body 6 attached to the shaft 3 in the radial direction by fluid pressure applied through a pressurized port 9 formed inside the shaft 3 and communicating with the groove 5. structure, so for example,
There is no need to provide a complicated mechanism for the purpose of displacing the shaft portion 3 in the axial direction, and the structure can be simplified and downsized.

Furthermore, when the gap 4 is annular and has a considerably large cross-sectional area, and the inlet flow path 7 and the outlet flow path 8 are communicated through the gap 4, the valve body 6 that closes the gap 4 is connected to the shaft portion 3. Since there are no protrusions or the like inside the gap 4 that increase flow resistance, the fluid flowing out from the inlet flow path 7 to the outlet flow path 8 through the gap 4 is pulled into the groove 5. The flow rate can be relatively large.

In addition, since the displacement due to expansion and contraction of the valve body 6 is small, the opening and closing operations are performed quickly, and the operations are performed quietly without any large impact.

Embodiment 2 FIG. 3 is a schematic sectional view showing the main parts of a directional control valve according to another embodiment of the present invention, and FIGS. 4 and 5 are respectively taken along the line -
and a schematic cross-sectional view of the portion indicated by the line -, No. 6
The figure is a schematic cross-sectional view for explaining the operation.

In this embodiment, the directional control valve is configured as a three-way valve.

That is, a plurality of grooves 5a and 5b are provided in the shaft portion 3a that is inserted into the cylinder portion 2a of the main body 1a with a predetermined gap 4, and a plurality of pressurized ports 9b and pressurized ports communicate with each other. 9b is formed inside the shaft portion 3a.

Then, the expansion and contraction in the radial direction of the plurality of valve bodies 6a and valve bodies 6b installed in the plurality of grooves 5a and 5b, respectively, is controlled by the pressurized ports 9a and 9b.
Controls the mutual opening and closing of the inlet passage 7a and the outlet passage 8a, which are opened at different positions in the axial direction of the cylinder portion 2a, as well as the exhaust port 15, by alternately applying fluid pressure to and controlling the cylinder part 2a. It is.

Further, the action of fluid pressure on the pressurized ports 9a and 9b is switched by, for example, supplying/blocking air or switching by a manual valve (not shown).

For example, as shown in FIG.
When fluid pressure is applied only to the pressurized port 9a that communicates with the valve body 6 installed in the groove 5a,
a is in close contact with the cylinder part 2a, and the inlet flow path 7
a toward the outlet flow path 8a and the exhaust port 15, and
and the exhaust port 15 are communicated with each other, and an operation is performed in which the residual pressure in the outlet channel 8a is discharged to the outside through the exhaust port 15.

Further, as shown in FIG. 6, when fluid pressure is applied only to the pressurized port 9b communicating with the groove 5b, only the valve body 6b attached to the groove 5b is in close contact with the cylinder 2a. , the outlet flow path 8a and the exhaust port 15 are blocked, and the inlet flow path 7
a and the outlet channel 8a are communicated with each other, and, for example, fluid such as compressed air is quickly supplied from the inlet channel 7a to the outlet channel 8a.

In the second embodiment, the same effects as in the first embodiment can be obtained.

Embodiment 3 FIG. 7 is a schematic sectional view showing the main parts of a directional control valve according to still another embodiment of the present invention, and FIG. 8 is a schematic sectional view illustrating its operation.

In the third embodiment, the directional switching valve is configured as a four-way valve.

That is, a plurality of grooves 5c, 5d, 5e, and 5f are formed in the shaft portion 3b inserted into the cylinder portion 2b of the main body 1b with a predetermined gap 4 therebetween.
are provided, a pair of grooves 5c and 5d and a groove 5
A plurality of pressurized ports 9c and 9d are formed inside the shaft portion 3b, communicating with each of the pressurized ports 9c and 5f.

A plurality of groove portions 5c, 5d and 5e, 5
A plurality of valve bodies 6c and valve bodies 6 respectively attached to f.
d, the valve body 6e, and the valve body 6f in the radial direction by controlling the expansion and contraction of the valve body 6e and the valve body 6f by alternately applying fluid pressure to the pressurized ports 9c and 9d. It controls opening and closing of the channel 7b, the plurality of outlet channels 8b, the outlet channel 8c, and the plurality of exhaust ports 15a and 15b.

That is, as shown in FIG.
In a state where fluid pressure is applied only to the pressurized port 9c communicating with the grooves 5c and 5d,
Only the valve bodies 6c and 6d attached to d are in close contact with the cylinder part 2b, and the inlet flow path 7b and one outlet flow path 8b are communicated with each other, so that compressed air is transferred from the inlet flow path 7b to the outlet flow path 8b. At the same time, the outlet flow path 8c and the exhaust port 15b are communicated with each other, and the residual pressure in the outlet flow path 8c is discharged to the outside through the exhaust port 15b.

Further, as shown in FIG. 8, a pair of groove portions 5
In a state where fluid pressure is applied only to the pressurized port 9d communicating with the grooves 5e and 5f, only the valve bodies 6e and 6f attached to the grooves 5e and 5f are in close contact with the cylinder portion 2b, and at this time, the inlet flow path 7b
and the outlet flow path 8c are communicated with each other, fluid is quickly supplied from the inlet flow path 7b to the outlet flow path 8c, and the outlet flow path 8c and the exhaust port 15a are communicated with each other.
For example, residual pressure in the outlet channel 8b is discharged to the outside through the exhaust port 15a.

In the third embodiment, the same effects as in the first embodiment can be obtained.

It goes without saying that the present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the spirit thereof.

For example, the cross-sectional shape of the annular valve body is not limited to circular, but may be rectangular, oval gourd-shaped, or any other shape.

Furthermore, the number of annular valve bodies may be five or more, and the number of pressurized ports may be three or more.

[Effects of the Invention] (1) A main body in which fluid passages are opened at different positions in the axial direction on the inner periphery of the cylinder part and the cylinder part are provided with a predetermined gap, and an annular groove is formed in the outer periphery. and a shaft portion having a pressurized port formed therein that communicates with the groove portion, and an elastic body, and is fitted into the groove portion, and
Since the structure includes an annular valve body that closes the gap by being expanded by the fluid pressure applied to the groove through the pressurization port, the fluid pressure applied to the pressurization port is The fluid passage can be opened and closed by expanding and contracting the annular valve body in the radial direction depending on the presence or absence of the spool shaft. This eliminates the need for sliding parts, etc., making the structure simpler and more compact.At the same time, when communicating with the fluid passage, the valve body is pulled into the groove by the elasticity of the valve body itself, and the shaft part There are no protrusions that increase flow path resistance between the outer periphery and the inner periphery of the cylinder portion of the main body, and the flow rate of the fluid to be controlled can be made relatively large.

(2) As a result of (1) above, since the displacement due to expansion and contraction of the valve body 6 is small, the opening/closing operation is performed quickly, and the operation is performed quietly without being accompanied by a large impact.

(3) As a result of (1) above, the manufacturing cost of the directional control valve can be reduced.

(4) As a result of (1) to (3) above, the performance of the directional control valve is improved.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing the main parts of a directional control valve that is an embodiment of the present invention, FIG. 2 is a schematic cross-sectional view that explains its operation, and FIG. FIG. 4 and FIG. 5 are schematic cross-sectional views showing the main parts of the switching valve. FIG. 4 and FIG. 5 are cross-sectional views of the portions indicated by lines and lines, respectively, in FIG. FIG. 7 is a sectional view showing essential parts of a directional control valve according to a third embodiment of the present invention, and FIG. 8 is a schematic sectional view illustrating its operation. 1, 1a, 1b...Main body, 2, 2a, 2b...
Cylinder part, 3, 3a, 3b...Shaft part, 4...Gap, 5...Groove part, 5a, 5b...Groove part, 5c, 5
d, 5e, 5f...Groove portion, 6...Valve body, 6a, 6
b... Valve body, 6c, 6d, 6e, 6f... Valve body,
7, 7a, 7b...inlet flow path (fluid passage), 8,
8a, 8b, 8c... Outlet channel (fluid passage), 9,
9a, 9b, 9c, 9d... pressurized port, 10...
...Pilot valve, 11...Solenoid, 12...
Plunger, 13...valve spring, 14...pilot exhaust port, 15, 15a, 15b...exhaust port.

Claims (1)

[Scope of Claims] 1. A main body in which fluid passages are opened at different positions in the axial direction on the inner periphery of a cylinder portion, and a main body provided with a predetermined gap between the cylinder portion and an annular groove portion formed on the outer periphery portion. , a shaft portion in which a pressurized port communicating with the groove is formed, and an elastic body, and the fluid pressure is fitted into the groove and is applied to the groove via the pressurized port. and an annular valve body that closes the gap by being expanded by a directional control valve. 2. A plurality of said valve bodies are arranged in the axial direction of said shaft part, and a plurality of said pressurized ports for individually controlling expansion and contraction of said plurality of valve bodies are formed inside said shaft part. A directional control valve according to claim 1, characterized in that: