JPH0953737A - Relief-check valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of parts and weight and improve economical property and reliability by compactly integrating a relief valve with a check valve in both directions used for a general industrial hydraulic apparatus or the like. SOLUTION: Relief valve poppets 7A, 7B and check valve poppets 8A, 8B are adapted to have in common a body 6, seat surface and oil path, while the relief valve poppets 7A, 7B in both directions are adapted to have a spring 9 in common. Also, the relief valve poppets 7A, 7B together with springs 10A, 10B are disposed symmetrically left and right.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve device which is used in general industrial hydraulic equipment and which has a bidirectional relief valve integrated with a check valve.

[0002]

2. Description of the Related Art FIG. 4 is a diagram showing an example of a conventional hydraulic circuit using a bidirectional relief valve and a check valve. In this figure, (1) is a pressure vessel, (2) is a piston that slides by dividing the pressure vessel (1) into two pressure chambers (1A) and (1B), (3) is a pressure accumulation chamber, and (4) ) Is a bidirectional relief valve having a poppet (4a), and (5) is a bidirectional check valve having balls (5a) and (5b).

For example, when the pressure in the pressure chamber (1A) rises, the poppet (4a) of the relief valve (4) moves to the left in the figure, the valve opens and a flow F1 is generated. This prevents abnormal pressure rise in the pressure chamber (1A).

When the pressure inside the pressure chamber (1A) becomes lower than the pressure inside the pressure accumulating chamber (3), the ball (5a) of the check valve (5) moves to the right in the figure, and the valve opens to flow. F
2. This prevents abnormal pressure reduction in the pressure chamber (1A).

In FIG. 4, a pipe line connecting the pressure accumulating chamber (3) and the relief valve (4) is provided for supplying a low pressurized hydraulic oil into the spring chamber of the relief valve.

[0006]

In the conventional hydraulic circuit, a bidirectional check valve and a bidirectional relief valve are required, and the number of oil passages connecting them is large, resulting in a complicated structure.

[0007]

In order to solve the above-mentioned conventional problems, the inventor of the present invention has a rod-shaped member arranged on the same axis, movable in the axial direction, and biased by a spring in a direction away from each other. And a pair of relief valve poppets, which are open at both ends, are arranged on the same axis outside the relief valve poppet, are movable in the axial direction, and are biased toward the relief valve poppet by a spring. And a pair of check valve poppets whose inner ends are closed by the relief valve poppets when the relief valve poppets are contacted. Communicating with each other,
And a relief check valve device, wherein the relief check valve device communicates with the pressure accumulating chamber, and the outer ends of the pair of check valve poppets respectively communicate with two pressure chambers separated by a piston that slides in the pressure container. Is proposed.

Since the present invention has the above-mentioned structure, when the internal pressure of one pressure chamber rises, when a certain pressure is reached, the relief valve poppet on one side moves and the check valve poppet on one side moves. The seat surface between and opens. Next, the other check valve poppet also moves and the seat surface between the other check valve poppet and the other relief valve poppet opens. Thus, a flow (main flow) from one pressure chamber to the other pressure chamber is generated.
The same applies to the reverse direction.

Further, when the internal pressure of the pressure chamber drops to a certain pressure, the check valve poppet moves to open the seat surface between the check valve poppet and the relief valve poppet, and the flow from the pressure accumulating chamber to the pressure chamber. (Replenishment flow) occurs.
The flow from the pressure chamber to the accumulator chamber is blocked because the check valve poppet is constrained from moving by the relief valve poppet.

[0010]

1 is a diagram showing a hydraulic circuit according to an embodiment of the present invention. In the figure, (6) is a body in which a pair of relief valve poppets (7A), (7B) and a pair of check valve poppets (8A), (8B) are arranged on the same axis line. It is contained.

The relief valve poppets (7A), (7
B) is rod-shaped, movable in the axial direction, and urged by springs (9) in directions (outward directions) away from each other. Also, the check valve poppet (8A), (8
B) is a tubular shape whose both ends are open and is arranged outside the relief valve poppets (7A) and (7B), is movable in the axial direction, and is directed toward the relief valve poppet (toward the inside). ) It is biased by springs (10A) and (10B). And the inner end is the relief valve poppet (7A),
It is designed to be closed when it contacts (7B).

The relief valve poppets (7A), (7
B) and the check valve poppets (8A) and (8B) are in contact with each other at their peripheries (11A) and (11B) at two positions, and also to the pressure accumulating chamber (3). Further, the outer ends of the pair of check valve poppets (8A) and (8B) are respectively connected to two pressure chambers (1A) and (1B) separated by a piston (2) sliding in the pressure vessel (1). are doing.

When the pressure in one of the pressure chambers delimited by the piston (2), for example, the pressure chamber (1A), rises, the relief valve poppet (7A) receives the force of the spring (9) as shown in FIG. It moves to the left in the figure to open the space between the check valve poppet (8A) and the check valve poppet (8A).
B) moves to the left in the figure against the force of the spring (10B) and opens between the relief valve poppet (7B), so that the hydraulic oil flows from the pressure chamber (1A) as indicated by the broken line arrow in the figure. Pressure chamber (1
It flows to B). When the pressure rise in the pressure chamber (1A) stops, the relief valve poppet (7A) moves to the right in the figure by the force of the spring (9) to close the space between the relief valve poppet (8A) and the check valve poppet (8A). (8B) is a spring (1
The force of 0B) moves to the right in the drawing to close the space between the relief valve poppet (7B) and the flow of the broken arrow is stopped. In this way, an abnormal rise in the pressure inside the pressure chamber (1A) is prevented. The pressure chamber (1B) is the opposite of the above.

When the pressure in the pressure chamber (1A) decreases and becomes lower than the pressure in the pressure accumulating chamber (3), the check valve poppet (8A) resists the force of the spring (10A) as shown in FIG. Then move to the right in Fig. A, and press the relief valve poppet (7
A) is opened, so that the hydraulic oil in the pressure accumulating chamber (3) flows toward the pressure chamber (1A) as indicated by a dashed arrow in the figure. When the pressure in the pressure chamber (1A) is restored, the check valve poppet (8A) moves to the left in the figure by the force of the spring (10A) and closes the space between the check valve poppet (7A) and the relief valve poppet (7A). Stop. In this way, it is possible to prevent the pressure in the pressure chamber (1A) from dropping abnormally. The same applies to the pressure chamber (1B).

According to this embodiment, the conventional relief valve,
Since one valve device has the function of a check valve, the number of parts and the number of oil passages can be reduced, weight and cost can be reduced, and reliability can be improved.

[0016]

According to the present invention, since the conventional relief valve and check valve are integrated, the overall size is reduced.
The number of parts and total weight are reduced, so that low cost and high reliability are achieved.

[Brief description of drawings]

FIG. 1 is a diagram showing a hydraulic circuit according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a function of the above embodiment.

FIG. 3 is a diagram illustrating another function of the above embodiment.

FIG. 4 is a diagram showing an example of a conventional hydraulic circuit using a bidirectional relief valve and a check valve.

[Explanation of symbols]

 (1) Pressure vessel (1A), (1B) Pressure chamber (2) Piston (3) Accumulation chamber (4) Relief valve (4a) Poppet (5) Check valve (5a), (5b) Ball (6) Body ( 7A), (7B) Relief valve poppet (8A), (8B) Check valve poppet (9) Spring (10A), (10B) Spring

Claims (1)

[Claims] 1. A pair of rod-shaped relief valve poppets arranged on the same axis line, movable in the axial direction, and biased by springs in directions away from each other, and a tubular shape having both ends open. The relief valve poppet is arranged on the same axis outside the valve poppet, is movable in the axial direction, and is biased by a spring toward the relief valve poppet, and when contacting the relief valve poppet, the inner end is the relief valve poppet. A pair of check valve poppets closed by means of a pair of check valve poppets, the relief valve poppet and the check valve poppet are in contact with each other at their peripheries and communicate with the pressure accumulating chamber. Relief check characterized in that the outer end communicates with two pressure chambers separated by a piston that slides in the pressure vessel. Valve device.