JPH0594220A - Pressure controller - Google Patents

Abstract

PURPOSE:To enable fine pressure control without causing any abrupt pressure drop, to improve rising characteristics, to simplify a controller and to reduce the cost CONSTITUTION:A bottomed cylindrical valve body 4 which is closed at one end side and opened at the other end side is provided, and a valve hole is bored in its bottom part side; and a low-pressure side chamber 26 is formed on the opening side and a relief valve 6 is provided slidably in the valve hole. A body cap 8 which closes the opening is added, a valve spring 10 which energizes the relief valve is provided, and a high-pressure side chamber 38 which is opened to the bottom part side of the valve body is formed in the relief valve; and a valve communication hole 70 which communicates with the high pressure side chamber is formed at the side position of the relief valve, a high-pressure side body communication hole 80 which communicates the valve communication hole and a low-pressure side body communication hole 76 which communicates with the low-pressure side chamber are formed at side positions of the valve body, and a pressure adjustment hole which gradually increases in opening area according to the movement of the relief valve is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure control device,
In particular, the present invention relates to a pressure control device that simplifies the handling of a pressure flow path and can appropriately perform pressure control.

[0002]

2. Description of the Related Art A pressure circuit for a fluid such as a liquid is equipped with a pressure control device for adjusting the pressure on the outlet side to a set pressure different from the pressure on the inlet side regardless of the magnitude of the pressure from the inlet side. There is something.

This pressure control device generally has a relief valve that reciprocates in the axial direction of the valve body in the valve body, and the stroke (movement) of the relief valve.
The fluid pressure is adjusted depending on the condition.

Such a pressure control device is disclosed, for example, in Japanese Utility Model Publication No. 1-14541. In this publication, the return spring of the spool valve of the flow control valve engages and supports the filter on the housing end wall so that it acts as a safety valve when the filter is clogged, and the filter acts against the spring. By moving in the direction, a bypass passage is formed through the outer peripheral side of the filter to prevent an increase in relief pressure and prevent damage to the hydraulically operated device.

[0005]

However, in the conventional pressure control device, since the high pressure inlet side and the low pressure outlet side communicate with each other at a stretch due to the movement of the relief valve, the pressure is rapidly reduced. As a result, the pressure control in the vicinity of the rising becomes rough and the rising characteristics are deteriorated.

Further, the handling of the pressure passage becomes complicated, and new passages must be added, which is disadvantageous in terms of construction.

[0007]

In order to eliminate the above-mentioned inconvenience, the present invention provides a bottomed tubular valve body having one end closed and the other end open. Has a valve hole on the bottom side and a low pressure side chamber having a diameter larger than that of the valve hole and communicating with the valve hole, and a relief valve is slidably provided in the valve hole. Is provided with a body cap for closing the opening, and a valve spring for urging the relief valve into the valve hole is provided between the body cap and the relief valve, and the relief valve has a bottom portion of the valve body. A high pressure side chamber that opens to the side, and a valve communication hole that communicates with the high pressure side chamber is formed at a side portion of the relief valve,
A high pressure side body communication hole communicating with the valve communication hole and a low pressure side body communication hole communicating with the low pressure side chamber are formed in the side portion of the valve body, and the relief valve of the relief valve is formed in the side portion of the relief valve. It is characterized in that a pressure adjusting hole whose opening area gradually increases according to the movement toward the body cap side is formed.

[0008]

According to the structure of the present invention, when a high-pressure fluid flows into the high-pressure side chamber to increase the pressure in the high-pressure chamber, the relief valve resists the urging force of the valve spring in the fluid flow direction on the body cap side. Then, the high-pressure fluid in the high-pressure side chamber moves into the low-pressure side chamber through the pressure adjusting hole, and the pressure of the fluid is kept constant. Since the pressure adjusting hole is formed so that the opening area gradually increases in accordance with the stroke (movement) of the relief valve, fine pressure control can be performed without causing a sudden pressure drop at low pressure near the fluid set pressure. It is possible to improve the rising characteristics.

[0009]

Embodiments of the present invention will now be described in detail and specifically with reference to the drawings. 1 to 12 show an embodiment of the present invention. In FIGS. 1 and 2, reference numeral 2 is a pressure control device. The pressure control device 2 includes a valve body 4, a relief valve 6, a body cap 8 and a valve spring 10.

As shown in FIG. 3, the valve body 4 is a bottomed cylindrical body whose one end side is closed by the bottom portion 12 and the other end side is opened by the body opening portion 14.
6 and the chamber forming portion 18. In this valve body 4, the valve holder 1 is oriented in the axial direction.
6, the valve hole 2 having an inner diameter D1 and a depth L1 from the bottom surface 20
A chamber for forming a bottom pressure side chamber 26 having an inner diameter D2 larger than the diameter D1 of the valve hole 22 and a depth L2 from the opening end face 24 in the chamber forming portion 18 on the body opening 18 side. A forming hole 28 is formed so as to communicate with the valve hole 22. As a result, a body step surface 30 is formed on the inner surface of the valve body 4 at the boundary between the valve hole 22 and the low pressure side chamber 26. The relief valve 6 is slidably fitted in the valve hole 22.

As shown in FIG. 4, this relief valve 6 has an outer diameter D3 of the valve body 32 slightly smaller than the inner diameter D1 of the valve hole 22 and a length from a valve end surface 34 on one end side which is in contact with the bottom surface 20. L3 is the valve hole 22
Is formed to have the same depth L1.

In the valve body 32 of the relief valve 6, a high pressure side chamber 38 is formed on the valve end face 34 side in the axial direction and opens at a valve opening 36. The high-pressure side chamber 38 has an inner diameter D4 and extends from the valve end surface 34 to the inner back surface 4
The depth up to 0 is formed in L4.

On the other end side of the valve body 32, a valve protrusion 42 is continuously provided in the axial direction. A valve screw hole 44 for fixing a bolt or the like from the axial direction for machining or the like is formed in the valve protruding portion 42 in the valve protruding end surface 4.
It is formed by opening to the 6 side. This valve protrusion 42
Has an outer diameter D5 smaller than the outer diameter D3 of the valve body 32. As a result, a valve step surface 48 is formed on the outer surface of the relief valve 6 at the boundary between the valve body 32 and the valve protrusion 42. This valve step surface 48
The valve protrusion end surface 46 of the valve protrusion 42 has a length L.
5 are formed.

As shown in FIG. 7, the body cap 8 has a closing portion 50 fitted into the chamber forming hole 28 and a flange portion 52 which is connected to the closing portion 50 and is in contact with the body opening end face 24. is doing. The closed portion 50 has a length L6 from the flange inner surface 54 to the closed portion inner surface 56, and an outer diameter D6 that is slightly smaller than the inner diameter D2 of the chamber forming hole 28. A ring groove 60 for accommodating the O-ring 58 (see FIG. 1) is formed on the outer peripheral surface of the closed portion 50.

As shown in FIG. 7, the flange portion 52 has a plurality of bolt insertion holes 62 formed at equal intervals in the circumferential direction. Corresponding to the bolt insertion holes 62, the chamber forming portion 18 of the valve body 4 is formed with a plurality of bolt screw holes 64 in the axial direction as shown in FIG.
Therefore, a cap bolt (not shown) is attached to the bolt insertion hole 6
By inserting it through 2 and screwing it into the bolt screw hole 64,
The body cap 8 is attached to the valve body 4.

The body cap 8 is provided with a cap projecting portion 66 which projects axially into the low pressure side chamber 26. The cap protrusion 66 is the valve protrusion 4
2 has an outer diameter D7 that is substantially the same as the outer diameter D5, and the inner surface 5 of the closed portion
The length from 6 to the cap projecting end face 68 is L7.

As shown in FIG. 1, a maximum distance S that the relief valve 6 can move is formed between the cap projecting end surface 68 of the cap projecting portion 66 and the valve projecting end surface 46 of the valve projecting portion 42. That is, the relief valve 6
The movement of is stopped when the valve protruding end surface 46 of the valve protruding portion 42 contacts the cap protruding end surface 68 of the cap protruding portion 66.

The valve spring 10 is constructed as shown in FIG. 8. As shown in FIG. 1, one end of the valve spring 10 is fitted to the valve protrusion 42 and locked to the valve step surface 48, and the other end is cap protrusion 66. The relief valve 6 is attached to the bottom surface 12 of the valve body 4 by locking the relief valve 6 on the inner surface 56 of the closed portion.
It is biased to the side.

In the valve body 32 of the relief valve 6, as shown in FIG. 4, first valve communicating holes 70, 70 having a diameter D8 are formed facing each other at a side portion on the valve end face 34 side. The axial direction of the first valve communication hole 70 is orthogonal to the axial direction of the relief valve 6. Further, at the side portion of the valve body 32, the first valve communication hole 70 and the substantially 9
The second valve communication hole 7 having a diameter D9 is located at a position rotated by 0 degree and on the valve end face 34 side of the first valve communication hole 70.
2, 72 are formed.

Further, in the side portion of the valve body 32, three pressure adjusting holes 74 are formed at equal intervals in the circumferential direction between the inner back surface 40 of the high pressure side chamber 38 and the first valve communicating hole 70 ( (See FIG. 5).

The pressure adjusting hole 74 has a width W on the inner back surface 40 side and a length M from the hole tip surface 76a in the axial direction of the relief valve 6 is set to M.
6 and a second adjusting hole 78 which is formed to have a diameter D10 and communicates with the first adjusting hole 76. Therefore, the pressure adjusting hole 7
4 is formed so that the opening area thereof gradually increases in accordance with the movement of the relief valve 6 toward the body cap 8 side.

As shown in FIG. 3, the first valve communicating hole 7 is formed in the valve body 16 on the side of the valve holding portion 16.
A high pressure side body communication hole 80 having a diameter D11 is formed so as to communicate with 0. A high pressure side passage 82 is communicated with the high pressure side body communication hole 80. The diameter D11 of the high pressure side body communication hole 80 is formed larger than the diameter D8 of the first valve communication hole 70. In addition, one surface 80a of the high pressure side body communication hole 80 and the first valve communication hole 70
The one surface 70a is the valve end surface 34 of the relief valve 6.
Are in substantially coincidence with each other when they are in contact with the bottom surface 20 of the bottom portion 12 (see FIG. 1).

The chamber forming portion 18 of the valve body 4 is also provided.
A low pressure side body communication hole 84 that communicates with the low pressure side chamber 26 is formed in the side portion. This low pressure side body communication hole 8
4 is formed to have a diameter D12 smaller than the diameter D11 of the high pressure side body communication hole 80. A low pressure side passage 86 is connected to the low pressure side body communication passage 84.

Next, the operation of this embodiment will be described.

When the pressure control device 2 is assembled, the valve body 32 of the relief valve 6 is fitted into the valve holding portion 16 of the valve body 4, and one end of the valve spring 10 is attached to the valve protruding portion 42 of the relief valve 6. While fitting the side, the other end of the valve spring 10 is fitted to the cap protrusion 66, and the flange portion 52 of the body cap 8 is brought into contact with the cap opening end surface 24 and attached with a cap bolt. As a result, the valve end surface 34 of the relief valve 6 contacts the bottom surface 20 by the urging force of the valve spring 10.

As a result, the relief valve 6 can be attached to the pressure control device 2 without separately providing a pressure passage, and the assembling property can be improved.

Further, the pressure passage can be formed by utilizing the chamber forming hole 28 as the mounting hole of the relief valve 6 and the valve hole 22, so that the device can be made compact and the structure can be simplified. be able to.

Further, since it is not necessary to process the pressure channel and the like, the device can be manufactured at low cost.

On the other hand, when the pressure of the fluid from the high pressure side passage 82 is increased during use, the relief valve 6 moves against the biasing force of the valve spring 10 as shown in FIG. When the hole tip surface 76a of No. 2 reaches the R position, the communication between the low pressure side chamber 26 and the high pressure side chamber 38 is started.

When the fluid pressure becomes stronger,
As shown in FIG. 10, the first adjusting hole 76 allows the high pressure side chamber 3
8 communicates with the low pressure side chamber 26, and the fluid flows into the low pressure side chamber 26. At this time, the fluid flows into the high-pressure side chamber 38 also from the valve opening 36, and the opening area of the first adjusting hole 76 is formed small. It is possible to perform fine pressure control without incurring a rise and improve the rising characteristics.

When the pressure of the fluid becomes stronger, the relief valve 6 moves to the second position as shown in FIG.
The adjusting hole 78 reaches the R position, which allows the pressure to be adjusted quickly. In other words, when the pressure of the fluid is suddenly increased, the stroke of the relief valve 6 is increased and a large opening area is obtained by the first and second adjustment holes 76 and 78, which causes pressure overshoot. There is no pressure control.

Furthermore, when the pressure of the fluid becomes strong,
As shown in FIG. 12, the relief valve 6 stops its movement when the valve protrusion 42 contacts the cap protrusion 66.

By the way, according to this construction, the relief valve 6 moves from the side where the fluid pressure is high to the side where the fluid pressure is low, so that the design of the valve body 4 to which the relief valve 6 is mounted becomes easy, and the manufacture is easy and the cost is low. It can be inexpensive.

[0034]

As is apparent from the above detailed description, according to the present invention, a bottomed tubular valve body having one end closed and the other end open is provided, and the valve body is provided with a valve on the bottom side. A hole is formed and a low pressure side chamber having a diameter larger than that of the valve hole and communicating with the valve hole is formed on the opening side, a relief valve is slidably provided in the valve hole, and a body cap is provided in the valve body to close the opening. A valve spring that urges the relief valve into the valve hole between the body cap and the relief valve.
The relief valve has a high pressure side chamber that opens to the bottom of the valve body, a relief valve side portion has a valve communication hole that communicates with the high pressure side chamber, and a relief portion has a high pressure side chamber that communicates with the valve communication hole. Side body communication hole and a low pressure side body communication hole communicating with the low pressure side body chamber are formed,
By forming a pressure adjusting hole in the side portion of the relief valve, the opening area of which gradually increases in accordance with the movement of the relief valve toward the body cap side, a rapid pressure drop occurs at a low pressure near the fluid set pressure. Without inviting, fine pressure control is possible, and overshoot is avoided to improve the start-up characteristics, and it is not necessary to separately provide a pressure flow path in the component parts of the device, and the structure is simplified. Compact, easy to manufacture, and low in cost.

[Brief description of drawings]

FIG. 1 is a sectional view of a pressure control device.

FIG. 2 is a front view of a pressure control device.

FIG. 3 is a sectional view of a valve body.

FIG. 4 is a sectional view of a relief valve.

5 is a cross-sectional view taken along the line VV of FIG.

6 is a cross-sectional view taken along the line 〓-〓 of FIG.

FIG. 7 is a sectional view of a body cap.

FIG. 8 is a side view of the valve spring.

FIG. 9 is a cross-sectional view of the pressure control device when starting communication between the high pressure side and the low pressure side.

FIG. 10 is a cross-sectional view of the pressure control device when the high pressure side and the low pressure side are communicated with each other by the first adjusting hole.

FIG. 11 is a cross-sectional view of the pressure control device when the high pressure side and the low pressure side are communicated with each other by a second adjustment hole.

FIG. 12 is a sectional view of the pressure control device in a state where the relief valve is maximally moved.

[Explanation of symbols]

 2 Pressure control device 4 Valve body 6 Relief valve 8 Body cap 10 Valve spring 26 Low pressure side chamber 42 Valve protrusion 74 Pressure adjusting hole

Claims (1)

[Claims] 1. A bottomed tubular valve body having one end closed and the other end open, the valve body having a valve hole on the bottom side and a valve hole on the opening side rather than the valve hole. A low pressure side chamber having a large diameter and communicating with the valve hole is formed, a relief valve is slidably provided in the valve hole, and a body cap is attached to the valve body to close the opening. A valve spring for urging the relief valve into the valve hole is provided between the relief valves, a high pressure side chamber opening to the bottom side of the valve body is formed in the relief valve, and the high pressure is provided at a side portion of the relief valve. A valve communicating hole communicating with the side chamber is formed, and a high pressure side body communicating hole communicating with the valve communicating hole and a low pressure side communicating with the valve communicating hole are formed in a side portion of the valve body. A low pressure side body communication hole communicating with the chamber is formed, and a pressure adjusting hole whose opening area is gradually increased according to the movement of the relief valve to the body cap side is formed in a side portion of the relief valve. Characteristic pressure control device.