JPH0546477B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a swivel joint particularly suitable for connecting piping that handles high-pressure water having a pressure of 1000 Kg/cm ² or more.

``Conventional technology'' In the Water Jet Plasting method (WJB method), which has traditionally been adopted as a tunnel excavation method, in order to excavate a tunnel by blasting the bedrock, the rock G A large number of blast holes 1 are formed in the blast holes 1, and slits 2 are formed in the blast holes 1. The reason for forming the slits 2 is to make the blasting pressure act effectively along the direction of the slits and to make the blasting surface smooth.

By the way, in order to form the blast hole 1 and the slit 2 in the above construction method, after forming the blast hole 1 using a rock drill (such as a drifter) equipped with a drilling tool consisting of a rod and a drilling bit, the drilling bit and rod are The work involves pulling out the water from the blasting hole 1, then inserting a high-pressure water lance for forming slits into the blasting hole 1, and drawing out the high-pressure water lance while spouting high-pressure water to form the slits 2. In this work, there is a problem in that the time required to pull out the drilling bit and rod and the time required to insert the high-pressure water lance results in a complete loss of work. Therefore, the applicant of the present invention
First, we are developing a drifter with a new configuration that incorporates a high-pressure water lance. However, when forming the slit 2 using this drifter, the second
In order to form the slit 2 in various directions as shown in the figure, or because it is preferable to obtain a constant high-pressure water injection direction with respect to the rotation angle of the rod, it is also necessary to connect it to a high-pressure pump. Because we want to keep the high-pressure hose connected at all times and turn on and off the high-pressure pump or valve as needed, we have incorporated a swivel joint that can meet the above requirements into the high-pressure water piping installed inside the drifter. There is a need.

An example of a conventionally known swivel joint is shown in FIG. 3.The conventional swivel joint 4 shown in FIG. The connecting pipe 6 is inserted freely, the connecting pipe 6 is prevented from coming off, and the outer peripheral surface of the connecting pipe 6 and the cylinder body 5 are
In this structure, a sealing material 7 is disposed at the sliding portion between the inner circumferential surface and the inner circumferential surface.

"Problems to be Solved by the Invention" In the conventional swivel joint 4 shown in FIG. Since the seal member 7 rotates and slides, the seal member 7 is subject to severe wear and has a drawback in that it has poor water-stopping properties.

The present invention was made in view of the above problems, and
The rotary block that rotates and slides has less influence on the sealing part and improves water-stopping performance.
It is an object of the present invention to provide a swivel joint that can obtain a sealing pressure corresponding to the water pressure of high-pressure water used.

"Means for Solving the Problems" The present invention includes a hollow storage body having a cylinder hole inside, a housing body rotatably stored in the front side of the storage body in the circumferential direction of the cylinder hole, and a cylinder hole in the center of the front side. A cylindrical rotating block having a storage hole formed therein, a high pressure pipe penetrating the front wall of the housing body and inserted into the housing hole of the rotating block, and a high pressure pipe stored in the rear side of the housing body so as to be freely accessible to the rotating block. the piston, and a biasing member disposed inside the storage body to bias the piston toward the rotating block; a protrusion is formed on the distal end surface of the piston; A concave receiving seat into which the protruding part of the piston is inserted is formed at the rear end, and a water supply channel that opens into the storage hole and the receiving seat is formed in the rotating block, and the distal end surface of the protruding part and the piston are provided in the piston. Inner water channels opening at the rear end surface are formed respectively, and an inlet hole communicating with the cylinder hole on the rear side of the piston is formed in the storage body.

"Operation" The pressure applied to the piston by supplying high-pressure water to the inlet hole and the urging force applied by the urging member press the protrusion of the piston against the receiving seat of the rotating block, causing the protrusion of the piston to rotate. A contact sealing pressure is generated between the block and the seat to send high pressure water to the high pressure pipe, and the rotating block rotates inside the storage body to correspond to the rotation angle of the high pressure pipe, and the contact between the high pressure pipe and the sealing material is Reduce wear between.

“Example” Figure 1 shows a swivel joint A according to an example of the present invention.
This swivel joint J connects the hollow storage body 10 with the rotating block 11 and piston 12 inserted into the housing body 10, the high pressure pipe 13 connected to the rotating block 11, and the Member 15
It is mainly composed of

The storage body 10 has a cylindrical shape with a cylinder hole 20 formed inside and closed at both ends, and has an insertion hole 21 formed in the center of its front wall and an inlet hole 22 formed in its rear peripheral wall. .

The rotating block 11 is a cylindrical block that is in contact with a recess 10a formed on the inner surface of the front wall of the storage body 10, is supported by a bearing 25, which will be described later, and is rotatably inserted in the circumferential direction of the cylinder hole 20. A small diameter cylindrical receiving portion 23 is protruded from the center of the rear end, and a recessed receiving seat 23a is provided at the center of the end surface of the receiving portion 23.
is formed. Note that this seat 23a is formed in a shape into which a tip portion (a truncated conical tip portion) of a protrusion 31 of the piston 12, which will be described later, can be fitted therein.

And, on the outside of this receiving part 23, there is a bush 2.
4 is fitted, and a receiving cylinder 26 is attached to the outside of this bushing 24, which extends to the rear of the receiving part 23 via a bearing 25. A storage cylinder 27 is attached to the rear of this receiving cylinder 26, and a storage cylinder 27 is installed in front of the receiving cylinder 26. The front part is inserted into the receiving cylinder 26, and is fitted with a space d between the front part and the bush 24. Furthermore, a support piece 29 having a protrusion 28 and fixed to the rear wall of the storage body 10 is provided at the rear of the storage cylinder 27, and the storage cylinder 27 accommodates the protrusion 28 of the support piece 29. It is inserted into the rear opening of the cylinder 27 and supported.

Also, a piston 12 is provided on the front side of the storage cylinder 27.
is inserted. This piston 12 has a thick-walled cylindrical shape with an internal waterway 30 formed inside, and a slightly raised protrusion 31 is formed at the center of its tip, and the tip of this protrusion 31 is formed in a tapered shape. An inclined sealing surface 32 is formed around the tip, and a protrusion 33 is formed at the center of the rear end of the piston 12. Then, the piston 12 inserts the protrusion 31 into the seat 23a of the rotating block 11, and
A chamber chamber 34 is opened in the housing tube 27 at the rear of the piston 12, and the piston 12 is inserted into the housing tube 27 so as to be freely accessible to the rotating block 11. Further, a spring member (biasing member) 15 for pressing the piston 12 toward the rotating block 11 is provided in the chamber chamber 34.
is stored. Note that the inclined seal surface 32
The area of the convex portion 3 is the area of the rear end surface of the piston 12.
It is formed smaller than the sum of the areas of the end faces of No. 3.

Also, between the storage tube 27 and the bush 24,
A rod-shaped anti-rotation member 14 having a width slightly smaller than the distance d is inserted into the space d, and a recess 35 is formed on the outer periphery of the proximal end of the protrusion 31 of the piston 12. The tip of the stopper member 14 is inserted, and the piston 12 can freely slide within the housing cylinder 27 until the stopper member 14 comes into contact with the inner wall of the recess 35 . The reason for restricting movement within this range is that the protrusion 3 of the piston 12
1 and the sealing surface 23a of the block 11, the protrusion 31 moves to the left in FIG. 1 by the biasing force of the spring member 15, and this is to limit the amount of movement (wear limit) at this time. .

Further, the storage tube 27 has a storage body 10 on the peripheral wall thereof.
A hose joint portion 36 communicating with the inlet hole 22 and the chamber chamber 34 is formed, and the hose joint portion 36 can be connected to a high pressure pump via a high pressure hose. In addition, 37 in the figure is
This is a bushing material stored in a groove formed on the inner circumferential surface of the storage tube 27.

On the other hand, on the front side of the rotating block 11, there is a storage body 1.
A storage hole 40 communicating with the insertion hole 21 of 0 is formed, and the end of the high-pressure pipe 13 passes through the insertion hole 21 and is inserted into the storage hole 40 so as to be slightly movable along the storage hole 40. A recess 41 of a predetermined width surrounding the storage hole 40 is formed in a part of the inner circumference of the storage hole 40 of the rotation block 11.
A water supply channel 42 that opens to 3a is formed, and circumferential grooves are formed around the recess 40, and a sealing material 43 is inserted into each circumferential groove.

The high-pressure pipe 13 is closed at its rear end, and the high-pressure water passage 45 therein is opened on the outer peripheral surface of the rear end of the high-pressure pipe 13 so as to communicate with the recess 40 inside the rotating block 11. are doing.

Next, the operation of the swivel joint configured as described above will be explained.

The swivel joint J with the above configuration is, for example, 1000
It is used to connect high-pressure piping built into rock drills that handle high-pressure water of Kg/cm ² or more, and forms part of the rock drill.

That is, the hose joint part 36 is connected to a high pressure pump via a high pressure hose, and the tip of the high pressure pipe 13 is directly connected to the rod of a rock drill equipped with a jet nozzle.
Or it can be connected indirectly and incorporated into a rock drill.
The high-pressure pump is connected to a rock drilling machine, and the slit 2 shown in FIG. 2 is formed by this rock drilling machine.

When high-pressure water is supplied from a high-pressure pump when forming the slit 2, the high-pressure water enters the chamber chamber 34 and then flows through the inner waterway 3 of the piston 12.
0 and water supply channel 42, passes through the recess 41, exits to the high pressure water channel 45 of the high pressure pipe 13, and is sent to the jet nozzle of the rock drill. Here, the piston 12 is pushed toward the rotating block 11 by the water pressure exerted by the high-pressure water in the chamber chamber 34 on the rear end surface of the piston 12 and the spring force exerted by the spring member 15. The portion 31 is the rotating block 11
The inner waterway 30 and the water supply channel 42 are connected to each other by being pressed against the seat 23a.

By the way, when the jet nozzle of the rock drill is forming the slit 2 shown in FIG. Although a rock drilling machine equipped with a jet nozzle does not rotate, the rock drilling machine may rotate due to an operator's operational error or the like, and a rotational force may be applied to the high-pressure pipe 13. In this case, since the high-pressure pipe 13 and the sealing material 43 are in strong contact with each other, the rotary block 11 and the high-pressure pipe 13
rotates to allow the high pressure pipe 13 to rotate, and the high pressure pipe 1
Reduce the torque applied to 3. Therefore, even if the high pressure pipe 13 unexpectedly rotates like this, the high pressure pipe 1
3. Torsional damage can be prevented.

At this time, as the rotating block 11 rotates, the seat 23a rotates while contacting the protrusion 31 of the piston 12. Here, the contact force between the protrusion 31 of the piston 12 and the seat 23a has the following relationship. First, the convex portion 31 of the piston 12
Assuming that A' is the sum of the area of the tip end surface of the piston 12 and the area of the inclined seal surface 32, and assuming that A is the sum of the area of the rear end surface of the piston 12 and the area of the end surface of the convex part 33, Assuming that the water pressure applied to is P, the spring force of the spring member 15 is k, and the coefficient of friction between the protrusion 32 and the seat 23a is μ, the contact force F is as follows: F={P It can be expressed by the formula (A-A')+k}×μ. This contact force F corresponds to the frictional force between the high-pressure pipe 13 and the sealing material 43, and is clearly smaller than the frictional force in the swivel joint of the conventional structure. Therefore, the force applied to the sealing material 43 is reduced, the life of the sealing material 43 is extended, and the water-stopping property is also improved.

By the way, as described above, the piston 12 is pressed against the seat 23a by the spring member 15 and the water pressure of the high-pressure water in the chamber chamber 34, and the contact sealing force between the seat 23a and the piston 12 is increased depending on the water pressure of the high-pressure water. Therefore, even if the high-pressure water sent from the high-pressure pump fluctuates or changes the water pressure, the optimum contact sealing force can be obtained.

The high-pressure pipe 13 is inserted into the storage hole 40 of the rotary block 11 so as to be able to move slightly along the storage hole 40, so that the high-pressure pipe 13 may be exposed to shocks caused by the operation of the rock drill or during rock drilling operations. The minute movement force acting in the length direction of the high-pressure pipe 13 can be absorbed by the movement of the high-pressure pipe 13, and the structure is such that it can be easily replaced even if only the high-pressure pipe is damaged.

"Effects of the Invention" As explained above, the present invention has a rotary block that connects high-pressure pipes through a sealing member and rotates inside the housing, and the rotation of the rotary block connects the sealing material and the high-pressure pipes. Since it can reduce the frictional force between the sealing material and the sealing material, it has the effect of extending the life of the sealing material and improving its water-stopping properties. In addition, since the protrusion of the piston is inserted into the seat of the rotating block and the protrusion is pressed against the seat by the pressure of high-pressure water and the biasing force of the spring member, the protrusion of the piston and the seat of the rotating block are The contact sealing force between the seat and the seat can be adjusted to a value that corresponds to the water pressure. Therefore, even if the high-pressure water sent from the high-pressure pump fluctuates or changes the water pressure, the optimum contact sealing force can be obtained. When the high-pressure pipe rotates unexpectedly due to an operator error, the torsional force that acts on the high-pressure pipe through the rotating block becomes a contact force associated with this contact sealing force, and this contact force is the torsional force of the high-pressure pipe. Since it is extremely small compared to the size of the pipe, it also has the effect of preventing torsional damage to high-pressure pipes.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of an embodiment of the present invention, Fig. 2 is a front view showing a blast hole and slit formed in rock when excavating a tunnel, and Fig. 3 is a cross-sectional view of a conventional swivel joint. be. J...Swivel joint, 10...Storage body, 11...
... Rotating block, 12 ... Piston, 13 ... High pressure pipe, 15 ... Spring member (biasing member), 20 ...
Cylinder hole, 22... Inlet hole, 23a... Seat,
30... Inner waterway, 31... Projection, 42... Water supply channel, 40... Storage hole, 43... Seal member.

Claims (1)

[Claims] 1. A hollow storage body with a cylinder hole inside;
A cylindrical rotating block that is rotatably housed in the front side of the storage body in the circumferential direction of the cylinder hole and has a storage hole formed in the center of the front surface, and a storage hole of the rotation block that penetrates the front wall of the storage body. A high-pressure pipe inserted through a sealing material, a piston stored in the rear side of the storage body so as to be freely accessible to the rotating block, and a piston placed inside the storage body to bias the piston toward the rotating block. A protrusion is formed on the distal end surface of the piston, and a recessed receiving seat into which the protrusion of the piston is inserted is formed on the rear end of the rotating block. In addition, the rotary block is formed with a water supply channel that opens to the storage hole and the receiving seat, and the piston is formed with an internal water channel that opens to the tip end surface of the protrusion and the rear end surface of the piston. A swivel joint having a self-adjusting sealing function, characterized in that an inlet hole communicating with a cylinder hole on the rear side of a piston is formed.