JP2022169332A - Pressure release plug and method for releasing pressure of hydraulic pipe - Google Patents

Abstract

To easily release residual pressure of a hydraulic pipe even in a case where the hydraulic pipe is twisted.SOLUTION: A pipe connection member 21 of a pressure release plug 20 is connected to a coupler 2 of a hydraulic pipe 1, a poppet contact member 23 provided on the pressure release plug 20 contacts a poppet 3 of the coupler 2 by screwing the inside of a pipe connection member 21 in a connection direction, the inside of the hydraulic pipe 1 and a connection part side oil reservoir 22 are communicated, and hydraulic oil in the connection part side oil reservoir 22 is discharged in the connection direction through a connection part side through hole 23a extending in the connection direction via a connection part side communication hole 23b of the poppet contact member 23.SELECTED DRAWING: Figure 1A

Description

TECHNICAL FIELD The present invention relates to a depressurization plug that is connected to a coupler of hydraulic piping to discharge hydraulic oil from the inside of the hydraulic piping, and a method of depressurizing the hydraulic piping.

Conventionally, in assembly and disassembly type work machines such as demolition machines, the joints that connect unit pipes have the advantage that they can be attached and detached with one touch, and there is almost no oil leakage when attaching and detaching. Closed joints called quick couplers, self-sealing couplings, etc. are used.

However, this type of joint incorporates a poppet type or spool type valve, and is structured to open the valve by a combined operating force. There is a problem that the pressure (residual pressure) acting as a resistance makes it difficult to connect the joints.

This phenomenon is particularly noticeable when the temperature of the trapped oil (residual oil) rises due to a rise in the outside air temperature and the residual pressure increases, or in the case of a large joint.

Therefore, for example, as in Patent Document 1, a cylindrical member that can be locked in a connected state using a part of a locking mechanism provided in both of the sockets in the self-sealing coupling, and a cylindrical member that is fixed to the tip thereof. and a cover-like member having a threaded hole along the axis of the cylindrical member formed in the center thereof; A valve having a threaded ronde and a residual pressure discharge pipe communicating with a tubular member, and provided inside the socket by advancing the rond in the axial direction while the tubular member is connected to the plug or socket. There is known a residual pressure release jig for a self-sealing coupling configured to push open the body with the tip of a rondo.

JP-A-57-40787

However, in the conventional depressurization plug, the residual pressure discharge pipe through which the hydraulic fluid is discharged extends in the radial direction of the lid-shaped member. There is a problem that it is difficult to handle.

SUMMARY OF THE INVENTION The present invention has been made in view of such a point, and its object is to easily release the residual pressure in the hydraulic piping even when the hydraulic piping is twisted.

In order to achieve the above object, the present invention has a simple configuration that discharges hydraulic fluid in hydraulic piping in the connection direction of a pressure relief plug.

Specifically, in the first invention, the object is a pressure relief plug that is connected to a coupler of hydraulic piping and that discharges hydraulic oil inside the hydraulic piping,
The above pressure relief plug is
a pipe connection member detachably connected to the coupler of the hydraulic pipe and extending in the connection direction of the coupler;
a connecting portion-side oil reservoir recessed in the interior of the pipe connecting member so that one side in the connecting direction is open;
A connecting portion-side through-hole extending in the connecting direction is formed inside the main body extending in the connecting direction, and one end portion in the connecting direction penetrates into the connecting portion-side oil reservoir in the connecting direction. a poppet abutting member that causes the inside of the hydraulic pipe to communicate with the connecting portion side oil reservoir by screwing the provided female screw portion toward the coupler side and abutting against the poppet of the coupler,
The poppet contact member has a connecting portion side communication hole that communicates the connecting portion side oil reservoir and the connecting portion side through hole at least in a state of contact with the poppet,
In a state in which the poppet contact member is in contact with the poppet, hydraulic oil inside the hydraulic pipe is discharged from the other side end of the connection portion side through hole.

According to the above configuration, the pipe connection member of the depressurization plug is connected to the coupler of the hydraulic pipe, and the poppet contact member is screwed toward the coupler and brought into contact with the poppet of the coupler, thereby connecting to the inside of the hydraulic pipe. communicates with the inner oil reservoir. At this time, the residual pressure of the hydraulic oil, which remains under residual pressure, is reduced by flowing into the connecting portion-side oil reservoir. Hydraulic piping is twisted by discharging the hydraulic oil in the connecting portion side oil reservoir in the connecting portion side communication hole provided in the poppet abutting member and the connecting portion side through hole extending in the connecting direction. Even in such a case, since the discharge direction of the hydraulic oil does not change from the connection direction, it is easy to handle the discharged hydraulic oil.

In the second invention, in the first invention,
The poppet contact member is
a connecting portion side fastening member in which the connecting portion side through hole is formed;
a discharge-side fastening member having a discharge-side through hole extending in the connection direction and a discharge-side communication hole intersecting with the discharge-side through hole, and fastened to the other side of the connection portion-side fastening member in the connection direction;
A sealing member is provided between the connecting portion side fastening member and the discharge side fastening member, and seals the connecting portion side through hole by abutting on the peripheral edge of the connecting portion side through hole. ,
By tightening the release-side fastening member into the connection-side fastening member, the sealing member is pressed to block the connection-side through hole,
In a state in which the release side fastening member is retracted and the sealing by the sealing member is released, the hydraulic oil inside the hydraulic pipe flows through the release side communication hole to the other side end of the release side through hole. It is configured to be released from

According to the above configuration, the through hole on the connecting portion side can be closed by the sealing member. Therefore, the pipe connecting member of the depressurization plug is connected to the coupler of the hydraulic pipe, and the poppet contact member is screwed to close the hydraulic pipe. Hydraulic oil does not immediately blow out even when the poppet seal is released. Therefore, by releasing the sealing of the connecting portion-side through-hole by the sealing member while securing the hydraulic oil recovery passage, the hydraulic oil does not suddenly spout out and contaminate the surroundings.

In a third invention, in the second invention,
The sealing member is composed of a ball member accommodated between the connecting portion side fastening member and the discharge side fastening member.

According to the above configuration, the connecting portion side through hole can be sealed with a simple and reliable configuration.

In a fourth invention, in the second or third invention,
On the other end side of the connection direction of the connection portion side fastening member, there is a second connection portion side through hole concentrically communicating with the connection portion side through hole and having an inner diameter smaller than that of the connection portion side through hole. The members are arranged concentrically,
A peripheral edge of the second connecting portion side through hole is sealed by the sealing member.

According to the above configuration, if the second connecting portion side through hole has an inner diameter smaller than that of the connecting portion side through hole, hydraulic oil can be sealed with a smaller sealing member.

A hydraulic piping depressurization method according to a fifth aspect of the present invention is directed to a hydraulic piping depressurization method for discharging hydraulic oil inside hydraulic piping using the depressurization plug according to any one of the first to fourth aspects of the invention. ,
The pressure release method for the above hydraulic piping is
connecting the pipe connection member to the coupler of the hydraulic pipe;
one end of the poppet abutting member in the connection direction is screwed toward the coupler and brought into contact with the poppet of the coupler to communicate the inside of the hydraulic pipe with the connection side oil reservoir,
A configuration in which hydraulic oil in the connecting portion-side oil reservoir is discharged in the connecting direction from the other end of the connecting portion-side through hole through the connecting portion-side communicating hole of the poppet contact member and the connecting portion-side through hole. and

According to the above configuration, the residual pressure of the hydraulic oil to which the residual pressure is applied is reduced by flowing into the connecting portion side oil reservoir portion. Since the hydraulic fluid in the connecting portion side oil reservoir can be discharged in the connection direction of the pressure release plug through the connecting portion side through hole, even if the hydraulic piping is twisted, the hydraulic fluid discharge direction is the connecting direction. , and it is easy to handle the released hydraulic oil.

As described above, according to the present invention, even when the hydraulic piping is twisted, the residual pressure in the hydraulic piping can be released easily.

FIG. 4 is a cross-sectional view showing the pressure relief plug according to the first embodiment in contact with a poppet of hydraulic piping; FIG. 4 is a cross-sectional view showing the pressure relief plug according to Embodiment 1 in an open state; 2 is a perspective view of the pressure relief plug according to Embodiment 1 as viewed from above; FIG. 3 is a perspective view of the pressure relief plug according to Embodiment 1 as seen from below. FIG. FIG. 4 is a cross-sectional view showing a depressurization plug according to a modification of Embodiment 1; FIG. 5 is a perspective view of a pressure relief plug according to a modified example of Embodiment 1 as viewed from above; FIG. 5 is a perspective view of a pressure relief plug according to a modified example of Embodiment 1 as viewed from below; FIG. 8 is a cross-sectional view showing a pressure relief plug according to Embodiment 2 in a position to abut against a poppet of hydraulic piping; FIG. 10 is a cross-sectional view showing the pressure relief plug according to Embodiment 2 in an open state; FIG. 11 is a perspective view of a pressure relief plug according to Embodiment 2 as viewed from above; FIG. 11 is a perspective view of the pressure relief plug according to Embodiment 2 as viewed from below;

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1)
Although details are not shown, a large demolition machine as an example using the depressurization plug 20 of Embodiment 1 of the present invention includes, for example, a lower running body, an upper rotating body including a hydraulic oil tank and a hydraulic source, and a lower boom. , boom foot cylinder, arm, arm cylinder, crusher, etc. Attachments used for demolition work, etc., include multiple hydraulic actuators such as hydraulic cylinders. Residual pressure remains inside and is cheap. In this state, there arises a problem that when reconnecting the hydraulic piping, the residual pressure acts as a resistance and the connection cannot be made.

As shown in FIG. 1A, the depressurization plug 20 according to the present invention is connected to the coupler 2 of the hydraulic pipe 1 in which residual pressure remains, so that the hydraulic fluid inside the hydraulic pipe 1 can be easily discharged. is possible.

As also shown in FIGS. 1A to 2B, the depressurization plug 20 includes a pipe connection member 21 detachably connected to the coupler 2 of the hydraulic pipe 1. As shown in FIG. The pipe connection member 21 of the present embodiment has, for example, a male threaded portion 21a on the outer periphery on one end side in the connection direction, and a hexagonal portion 21b on the other end side in the connection direction. It has become. If the coupler 2 side is a so-called quick coupler, the male threaded portion 21a may also have a shape corresponding thereto. The pipe connection member 21 may be a female type that is screwed into the coupler 2 as in a modification described later.

Inside the male screw portion 21a of the pipe connection member 21, a connection portion side oil reservoir portion 22 is provided which is recessed so that one end side in the connection direction (connection direction, lower side in FIG. 1A) is open. A female screw portion 21c is formed in the center so as to be continuous with the connecting portion side oil reservoir portion 22 and penetrates in the connection direction (axial direction) of the pressure release plug 20 .

A poppet abutting member 23, in which a male threaded portion formed on a contacting member main body 23c as a fastening portion-side fastening member is screwed into the female threaded portion 21c, is screwed in or out (screwed) inside the pipe connection member 21. advance or loosen to retreat) is possible.

As shown in FIG. 1A, the poppet abutment member 23 has a connection portion side through hole 23a extending in the connection direction formed therein, and spirals inside the pipe connection member 21 in the connection direction to engage the poppet of the coupler 2. As shown in FIG. 3 is pressed down, the sealing of the poppet 3 is released, and the inside of the hydraulic pipe 1 and the connecting portion side oil reservoir 22 are communicated with each other.

Hydraulic oil in the connecting portion side oil reservoir portion 22 flows through a connecting portion side communicating hole 23b that communicates with the connecting portion side through hole 23a provided in the poppet contact member 23 and extends in the radial direction. It is designed to be discharged from the other end side (opposite side) in the connection direction through . The connecting portion side communication hole 23b is, for example, composed of one drill hole extending in a straight line, but may be composed of two orthogonal drill holes.

A small-diameter member 24 is fastened to the side opposite to the connection direction of the poppet abutment member 23 as a connection portion side fastening member in which a discharge side oil reservoir portion 25 is formed. The small-diameter member 24 is a fastening member having a second connecting portion-side through hole 24a having an inner diameter smaller than that of the connecting portion-side through hole 23a and having a male threaded portion formed at least partially on the outer circumference. A release-side oil reservoir 25 is recessed on the opposite side of the small-diameter member 24 in the connecting direction.

A ball member 26 is accommodated in the discharge side oil reservoir 25 as a sealing member that abuts on the periphery of the second connection portion side through hole 24a to seal the second connection portion side through hole 24a. . This ball member 26 is not connected to any other component within the discharge side oil reservoir portion 25 . The sealing member is desirably spherical so that it can move freely within the discharge side oil pool 25, but it may be composed of a hemispherical portion and a columnar portion that can move within the discharge side oil pool 25 in the connecting direction. . As in the present embodiment, if the second connecting portion side through hole 24a has an inner diameter smaller than that of the connecting portion side through hole 23a, the smaller ball member 26 can seal hydraulic oil. In addition, the contact portion of the second connecting portion-side through hole 24 a with the ball member 26 may be tapered in order to improve the adhesion with the ball member 26 .

A female threaded portion is formed on the inner peripheral surface of the release side oil reservoir portion 25 of the poppet contact member 23, and a release side fastening member 27 is fastened to the female threaded portion. The discharge side fastening member 27 is formed with a discharge side through hole 27a extending in the connection direction, and a male threaded portion on the outer periphery thereof is screwed into a female threaded portion of the discharge side oil pool portion 25 so that the discharge side oil pool portion 25 is closed. , and presses the ball member 26 to close the second connecting portion side through hole 24a. In this way, the second connecting portion side through hole 24a (and consequently the connecting portion side through hole 23a) can be sealed with a simple and reliable configuration.

Hydraulic oil in the release-side oil reservoir 25 communicates with the release-side through hole 27a provided in the release-side fastening member 27 in a state in which the release-side fastening member 27 is retracted to release the sealing by the ball member 26. It is configured to be discharged in the connection direction through the discharge side through hole 27a via the discharge side communication hole 27b. The discharge-side communication hole 27b is, for example, composed of a single radially extending through-hole communicating with the discharge-side through-hole 27a. good.

- How to release pressure from hydraulic piping -
Next, a depressurization method for the hydraulic pipe 1 according to the present embodiment will be described including removal of the attachment.

(1) Removal of attachment (disassembly)
First, after depressurizing the hydraulic piping circuit of the attachment to be removed, the hydraulic piping 1 is separated at the hydraulic coupler 2 on the side or back of the attachment.

Next, only the pipe connection member 21 of the depressurization plug 20 is screwed into the coupler 2 of the separated hydraulic pipe 1 . At this time, the hexagonal portion 21b can be tightened using a tool.

After tightening the pipe connection member 21, confirm that the release side fastening member 27 attached to the poppet contact member 23 of the depressurization plug 20 is firmly tightened. The male screw portion is securely tightened into the female screw portion 21c.

During this tightening process, the tightening force increases due to the repulsive force of the poppet 3 from the time when the contact member main body 23c of the depressurization plug 20 contacts the poppet 3 of the coupler 2 at one end in the connection direction. Even in this case, the hexagonal head portion of the contact member main body 23c can be tightened with a tool such as a wrench, so the tightening operation is easy.

When the abutting member main body 23c is completely tightened, the mounting of the pressure relief plug 20 is completed. As a result, the pressure can be released using the pressure release plug 20 .

(2) Next, a method of using the pressure release plug 20 during assembly will be described.

First, a discharge hose (not shown) is connected to the discharge side fastening member 27 of the depressurization plug 20, and the tip of the hose is inserted into a container such as a pail.

In the present embodiment, since the ball member 26 can block the connection portion side through hole 23a, the pipe connection member 21 of the pressure release plug 20 is connected to the coupler 2 of the hydraulic pipe 1, and the poppet contact member 23 is screwed. Hydraulic oil does not spout out immediately even if the hydraulic pipe 1 is released from the sealing by the poppet 3. Therefore, by releasing the sealing of the connecting portion side through-hole 23a by the ball member 26 in a state in which the hydraulic fluid recovery passage is secured, the hydraulic fluid does not suddenly spout out and the surroundings are not soiled.

By loosening or tightening the release-side fastening member 27, the hydraulic oil remaining inside the hydraulic pipe 1 is discharged, thereby increasing the pressure in the hydraulic pipe 1 during storage (rising due to the outside air, etc.). Pressure can be adjusted. At this time, the residual pressure of the hydraulic fluid in the hydraulic pipe 1 is reduced by flowing into the connection side oil reservoir 22 .

As shown in FIG. 1A, when the release side fastening member 27 is loosened several turns in the loosening direction from the state where the pressure release plug 20 is attached to the tip of the hydraulic pipe 1, the hydraulic oil is discharged and the internal pressure is lowered. In the present embodiment, hydraulic fluid in the connecting portion side oil reservoir 22 can be discharged in the connecting direction through the connecting portion side through hole 23a and the second connecting portion side through hole 24a extending in the connecting direction. Even if the hose is twisted, the discharge direction of the hydraulic oil does not change from the connection direction, and the discharge hose is easy to handle.

(3) Attachment installation (assembly)
Next, the depressurization plug 20 is removed from the coupler 2 of the hydraulic piping 1 from which residual pressure and residual oil have been released. Hydraulic oil remaining in the hydraulic pipe 1 is not blown out by the action of the poppet.

After that, the hydraulic piping on the attachment side and the hydraulic piping 1 on the main body side are connected by the coupler 2 . At this time, since the residual pressure and residual oil are released, the connection can be easily made without large resistance. This completes the connection of the hydraulic pipe 1 .

Therefore, according to the depressurization plug 20 and the method for depressurizing the hydraulic pipe 1 according to the present embodiment, even if the hydraulic pipe 1 is twisted, the residual pressure of the hydraulic pipe 1 can be easily released.

-Modification-
3, 4A and 4B show a depressurization plug 20' according to a modification of the embodiment of the present invention, which differs from the embodiment in that the shape of the pipe connection member 21' is different. It should be noted that, in the following modifications and the second embodiment, the same parts as those in FIGS. 1A to 2B are denoted by the same reference numerals, and detailed description thereof will be omitted.

The depressurization plug 20' of this modified example differs from the first embodiment in that the pipe connection member 21' has a female shape. Almost the entire outer circumference of the pipe connection member 21' is composed of the hexagonal portion 21b. A female screw portion 21a' is provided on the inner peripheral surface of the connecting portion side oil reservoir portion 22. As shown in FIG.

Since other configurations and effects are the same as those of the first embodiment, description thereof will be omitted.

(Embodiment 2)
5A to 6B show a depressurization plug 120 according to Embodiment 2 of the present invention, which differs from Embodiment 1 mainly in that it does not have a ball member 26 and a discharge side fastening member 27. FIG.

In the depressurization plug 120 according to this embodiment, the connecting portion side fastening member 124 has a simple structure that does not have the ball member 26 and the discharge side fastening member 27 .

In this embodiment, when the pipe connection member 21 is connected to the coupler 2 of the hydraulic pipe 1 and the poppet contact member 23 is tightened to release the sealing by the poppet 3, the hydraulic oil in the hydraulic pipe 1 flows. It has become.

For this reason, in this embodiment, before tightening the poppet contact member 23, a discharge hose or the like (not shown) is connected to the opposite side of the connecting portion side fastening member in the connection direction, and the tip of the discharge hose or the like is used to discharge the hydraulic oil. It is sufficient to insert it into a container such as a pail for the purpose. Alternatively, if a pipe returning to the tank of the working machine is connected as a discharge hose, it becomes unnecessary to discard the hydraulic oil.

A discharge-side oil reservoir 125 is provided on the opposite side of the contact member main body 23c in the connection direction, a ball member 26 is provided in this discharge-side oil reservoir 125, and the connecting portion-side fastening member 124 is fastened as a discharge-side fastening member. Thus, the connecting portion side through hole 23a may be sealed. This modification corresponds to the case where the small-diameter member 24 is not provided in the first embodiment.

Therefore, the pressure release plug 120 according to the present embodiment can also easily release the residual pressure of the hydraulic pipe 1 even when the hydraulic pipe 1 is twisted.

(Other embodiments)
The present invention may be configured as follows for the above embodiment.

That is, in the above-described embodiment, the hydraulic piping 1 in which residual pressure remains is the hydraulic piping 1 of the attachment of the working machine, but the present invention is not limited to this. The present invention is not limited to working machines, but can be applied to the coupler 2 of the hydraulic pipe 1 connected to hydraulic equipment and having residual pressure.

In the first embodiment, the small-diameter member 24 having the discharge-side oil reservoir 25 is fastened to the opposite side of the poppet contact member 23 in the connection direction. A discharge side oil reservoir 25 may be formed on the side opposite to the connection direction of the contact member main body 23c as a part side fastening member, and a ball member 26 may be provided, and a discharge side fastening member 27 may be fastened. In this case, the outer diameter of the ball member 26 is increased.

The above embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its applications, or uses.

1 hydraulic piping
2 Coupler
3 Poppet
20,20' plug
21, 21' pipe connection member
21a Male screw part
21a' Female screw part
21b hexagon
21c female screw
22 Connection side oil reservoir
23 Poppet contact member
23a connecting part side through hole
23b Connection side communication hole
23c abutting member main body (connecting part side fastening member)
24 Small-diameter member (connection side fastening member)
24a Second connecting portion side through hole
25 discharge side oil reservoir
26 ball member (sealing member)
27 release side fastening member
27a discharge side through hole
27b discharge side communication hole
120 Plug
124 connecting part side fastening member
125 discharge side oil reservoir

Claims (5)

A depressurization plug connected to a coupler of a hydraulic pipe to discharge hydraulic oil inside the hydraulic pipe,
a pipe connection member detachably connected to the coupler of the hydraulic pipe and extending in the connection direction of the coupler;
a connecting portion-side oil reservoir recessed in the interior of the pipe connecting member so that one side in the connecting direction is open;
A connecting portion-side through-hole extending in the connecting direction is formed inside the main body extending in the connecting direction, and one end portion in the connecting direction penetrates into the connecting portion-side oil reservoir in the connecting direction. a poppet abutting member that causes the inside of the hydraulic pipe to communicate with the connecting portion side oil reservoir by screwing the provided female screw portion toward the coupler side and abutting against the poppet of the coupler,
The poppet contact member has a connecting portion side communication hole that communicates the connecting portion side oil reservoir and the connecting portion side through hole at least in a state of contact with the poppet,
A depressurization plug, wherein hydraulic oil inside the hydraulic pipe is discharged from the other side end of the connecting portion side through hole in a state in which the poppet contact member is in contact with the poppet. A pressure relief plug according to claim 1, wherein
The poppet contact member is
a connecting portion side fastening member in which the connecting portion side through hole is formed;
a discharge-side fastening member having a discharge-side through hole extending in the connection direction and a discharge-side communication hole intersecting with the discharge-side through hole, and fastened to the other side of the connection portion-side fastening member in the connection direction;
a sealing member that is accommodated between the connecting portion side fastening member and the discharge side fastening member and that abuts against a peripheral edge of the connecting portion side through hole to seal the connecting portion side through hole;
By tightening the release-side fastening member into the connection-side fastening member, the sealing member is pressed to block the connection-side through hole,
In a state in which the release side fastening member is retracted and the sealing by the sealing member is released, the hydraulic oil inside the hydraulic pipe flows through the release side communication hole to the other side end of the release side through hole. A pressure relief plug, characterized in that it is discharged from a In the pressure relief plug according to claim 2,
A depressurization plug, wherein the sealing member comprises a ball member that is accommodated between the connection side fastening member and the discharge side fastening member. The pressure relief plug according to claim 2 or 3,
On the other end side of the connection direction of the connection portion side fastening member, there is a second connection portion side through hole concentrically communicating with the connection portion side through hole and having an inner diameter smaller than that of the connection portion side through hole. The members are arranged concentrically,
A depressurization plug, wherein a peripheral edge of the second connecting portion side through-hole is sealed by the sealing member. A depressurization method for a hydraulic pipe for discharging hydraulic oil inside the hydraulic pipe using the depressurization plug according to any one of claims 1 to 4,
connecting the pipe connection member to the coupler of the hydraulic pipe;
one end of the poppet abutting member in the connection direction is screwed toward the coupler and brought into contact with the poppet of the coupler to communicate the inside of the hydraulic pipe with the connection side oil reservoir,
Hydraulic oil in the connecting portion-side oil reservoir is discharged in the connecting direction from the other end of the connecting portion-side through hole through the connecting portion-side communicating hole of the poppet contact member and the connecting portion-side through hole. A method for depressurizing hydraulic piping, characterized by:

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