JP3193607B2 - Expansion joint structure of pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an expansion joint structure for a pipe, and more particularly to an improvement in a joint structure used for various piping systems such as a water pipe and facility piping.

[0002]

2. Description of the Related Art This type of expansion joint has been used mainly for buried pipes such as water pipes buried in the ground, but in recent years, it has also been used for equipment pipes in buildings. It has been widely adopted.

In such a telescopic joint, it is necessary to prevent the joint from unnecessarily extending when the telescopic joint is extended to prevent the occurrence of water leakage and the like. Was regulated by concrete and buried earth pressure.

[0004]

However, since such conventional extension restricting means relies on concrete, buried earth pressure, etc., it cannot exert a sufficient extension preventing function depending on the construction state. Therefore, there is a great problem that considerable care must be taken during the construction, which makes a series of operations very complicated.

Further, it is difficult to apply the above-mentioned conventional extension restricting means to equipment pipes for buildings and the like, and in such equipment pipes and the like, it is necessary to apply an external force due to, for example, shaking of an earthquake. When released, it is preferable to return to the original connected state as much as possible. However, there is no appropriate extension restricting means that satisfies such a condition.

SUMMARY OF THE INVENTION Therefore, the present invention has been made to solve the above-mentioned conventional problems, and it is possible to surely prevent the extension of the pipe body, and to improve the facility piping and the like in a building. It is another object of the present invention to provide a joint structure that can be widely applied.

[0007]

That is, a means adopted by the present invention to solve the above-mentioned problem is a joint structure for connecting the tubes 1 and 12 so as to be able to expand and contract. An inner tube 7 having one end slidably fitted to the other end and the other tube 12 fixed to the other end, and an outer tube fixed to the outer peripheral surface of one tube 1 which is externally fitted to the tubes 1 and 12. And a space 19 formed between the inner peripheral surface of the outer tube 17, the outer peripheral surface of the inner tube 7 and the outer peripheral surface of the other tube 12, and the end surface of the one tube 1. On the outer peripheral surface of the other end of the inner pipe 7, an annular convex section 8 slidable on the inner peripheral face of the outer pipe 17 is provided so as to be divided into two chambers 20 and 21 . Fluid flows through pipes 1 and 12
So that the fluid flows into the rear chamber 21 when
A through-hole 16 communicating with the post-chamber 21 is opened, and the outer pipe 17 is provided.
A through hole 22 communicating with the front chamber 20 is opened,
The area of the one end side end face 7a of the inner pipe 7 and the annular projection of the inner pipe 7
The point is that the area of the end face 7b of the portion 8 is set to be the same .

Accordingly, in the joint structure characterized by the above-mentioned structure, when a fluid is circulated from one of the pipes 1, a fluid pressure is applied to the end face of one end of the interior pipe 7 fitted into the pipe 1. A force acts in the pipe length direction to cause the other pipe body 12 to extend through the inner pipe 7, but a through hole 16 communicating with the rear chamber 21 is formed in the other pipe body 12. As a result, a part of the fluid flows into the rear chamber 21 from the through hole 16 and a fluid pressure is also applied to the end face of the annular convex portion 8 of the inner pipe 7. The force also acts in a direction that regulates the extension operation of the other tube body 12 via the other. As a result, the elongating operation of the tubular body 12 is regulated, and the connected state of the two tubular bodies 1 and 12 is maintained.

In this state, if an external force is applied to the tubes 1, 12, etc., for example, in the lengthwise direction, the other tube 12, together with the inner tube 7, will expand and contract with respect to the one tube 1. In addition, while the external force is favorably absorbed, after such an operation, the extension operation between the tubes 1 and 12 is regulated again as described above, and the connected state is maintained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a spherical bulge 2 at one end.
Is formed, and a step portion 3 is provided on its inner peripheral surface so that the other end has a large diameter, and a screw portion 4 is engraved on the outer peripheral surface of the other end. . 5 is a pair of concave grooves formed in the inner peripheral surface on the other end side of the tube body 1 in the circumferential direction.
Are provided with O-rings 6, respectively.

Reference numeral 7 denotes an inner tube whose one end is slidably fitted into the other end of the tube body 1. An annular convex portion 8 is provided on the outer peripheral surface of the other end in the circumferential direction, and on the inner peripheral surface. Is formed with a step portion 9 so that the other end has a large diameter. Reference numeral 10 denotes a groove formed in the annular convex portion 8 of the inner pipe 7 in the circumferential direction.
Each of the rings 11 is mounted. The area of the end face 7a of one end of the interior pipe 7 is set to be the same as the end face 7b of the annular projection 8.

Reference numeral 12 denotes the other tube having a spherical bulge 13 formed at one end, and a threaded portion 14 engraved on the outer peripheral surface of the other end.
Is screwed into a screw portion 15 provided on the inner peripheral surface of the other end portion of the interior pipe 7, and a plurality of through holes 16 are formed inside the screw portion 14 at predetermined intervals in the circumferential direction.

Reference numeral 17 denotes an outer tube having a threaded portion 18 which is screwed into the threaded portion 4 of one of the tubes 1 on the inner peripheral surface at one end.
A space 19 formed between the inner peripheral surface of the inner tube 17, the outer peripheral surface of the inner tube 7 and the outer tube of the other tube 12, and the end surface of the one tube 1 is an outer tube
The interior tube 7 is slidably fitted into the interior tube 7 and is divided into two front and rear chambers 20 and 21 by the annular projection 8. A through hole 22 communicating with the front chamber 20 is formed inside the screw portion 18. It is opened with a predetermined interval in the direction. The rear chamber 21 of the space 19 communicates with the inside of the other tubular body 12 through the through hole 16.

Reference numeral 23 denotes a pair of concave grooves formed on the inner peripheral surface of the other end of the outer tube 17 in the circumferential direction. Each groove 23 has an O-ring 24 mounted thereon. Reference numeral 25 denotes a joint pipe in which spherically slidable spherical concave portions 26 are formed on the inner peripheral surface of one end portion of the spherical bulging portions 2 and 13 of the respective tube bodies 1 and 12, 27 is an O-ring, and 28 is a joint tube. Tube 25 and tube 1,
12 shows an annular stopper for preventing the disengagement of 12;

The present embodiment has the above configuration.
As shown in FIG. 2, such a pipe joint is connected to another pipe A or B, such as a water pipe shown by a two-dot chain line, and is buried in the ground. At this time, since the other pipe 12 can be expanded and contracted with the one pipe 1 via the inner pipe 7, the pipe joint can be appropriately expanded and contracted to easily connect the other pipes A and B. Can be.

When a fluid flows from the pipe A to the pipe B, a fluid pressure P ₁ is applied to one end face 7 a of the inner pipe 7, and a part of the fluid passes through the other pipe 12. It flows into the rear chamber 21 of the space 19 from the hole 16, but the end face of one end of the interior pipe 7.
Area 7a is to become set in the same area as the end surface 7b of the annular projection 8, so that said fluid pressure P ₁ equal fluid pressure P ₂ applied to the end face 7b of the annular protrusion 8. Therefore, since the two are canceled and the equilibrium state is maintained, the extension operation of the pipe joint is reliably restricted.

When a large external force due to an earthquake or the like is applied to the pipe joint, the above-mentioned equilibrium state is released. However, the pipe bodies 1 and 12 are spherically slidable on the spherical bulging parts 2 and 13 thereof. Since it is connected to the other pipes A and B via the joint pipe 25 having the spherical concave portion 26, the inner pipe 7 moves and the pipe joint expands and contracts as shown in FIG. The connected state is favorably maintained while absorbing the external force.

In this case, since the outer tube 17 is formed with a through-hole 22 communicating with the front chamber 20, the through-hole 22 is formed.
Then, the air flows in, and the interior pipe 7 moves smoothly.

Even after such an operation, since the equilibrium state by the fluid pressures P ₁ and P ₂ is maintained as described above and the elongation operation of the pipe joint is regulated, this connection state is maintained. It is done.

As described above, by using the pressure of the flowing fluid as the extension restricting means of the pipe joint, the extension operation is restricted not only at the time of the initial connection but also after the expansion and contraction and the swinging operation. This is the most suitable as this kind of extension means, and the whole structure is very simple.

In the above-described embodiment, the outer tube 17 is provided with the through hole 22 so that the air can freely flow to the front chamber 20, but the through hole 22 may be omitted. . In this case, when the pipe joint performs the extension operation, the pressure in the front chamber 20 decreases to a negative pressure state, which acts to regulate the extension operation of the pipe joint. Room
The air in the front chamber 20 acts as a force to return to the original connection state in any case because the air in the chamber 20 functions as a damper, and in particular, it is used as a facility piping of a building. Will be optimal.

Further, in the above embodiment, the joint pipes 25 each having the spherical bulging portions 2 and 13 provided on the respective tubular bodies 1 and 12 and having the spherical slidable spherical concave portions 26 on the spherical bulging portions 2 and 13 are provided. Are connected, but it is not always necessary to configure in this way.

Further, the inner tube 7 and the other tube 12 do not need to be formed separately as in the above-described embodiment, and both can be formed as one body.

Further, if the area of the end face 7a of one end of the inner pipe 7 is set to be smaller than the area of the end face 7b of the annular projection 8,
Wherein the direction of the fluid pressure P ₂ acting on the end surface 7b one end face 7a
To become greater than the fluid pressure P ₁ acting on the interior pipe 7
The other pipe 12 is always pressed to the one pipe 1 side via the, so that there is an advantage that it functions to restrict the extension of the pipe joint.

[0026]

As described above, the present invention utilizes the fluid pressure of the flowing fluid as the means for restricting the extension of the pipe joint.
Even when this is used for buried pipes such as water pipes, it is not necessary to rely on concrete or buried earth pressure as in the past, and it is possible to reliably prevent pipe joints from extending, A special effect has been obtained in that it can be widely applied not only to pipes but also to facility piping for buildings.

Further, since the joint structure according to the present invention has a very simple structure as a whole, it has a practical effect that it can be manufactured easily and at low cost.

[Brief description of the drawings]

FIG. 1 is a half sectional view showing one embodiment of a pipe joint according to the present invention.

FIG. 2 is a half sectional view showing the same use state.

FIG. 3 is a half sectional view showing the same use state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tube 7 ... Interior tube 7a ... One end side end surface 7b ... End surface 8 ... Annular convex part 12 ... Tube 12 16 ... Through hole 17 ... Exterior tube 19 ... Space part 20 ... Front room 21 ... Rear room 22 ... Penetration Hole

Claims (3)

(57) [Claims] 1. A joint structure for connecting pipes (1) and (12) so as to be extendable and contractible, wherein one end is slidably fitted into one pipe (1) and the other end is connected to the other end. An inner pipe (7) to which the other pipe (12) is fixed, and one pipe which is externally fitted to the pipes (1) and (12)
(1) comprising an outer pipe (17) fixed to the outer peripheral face, and the inner peripheral face of the outer pipe (17), the inner pipe (7), and the other pipe.
The inner pipe is formed so as to partition the space (19) formed between the outer peripheral surface of the pipe (12) and the end face of the one pipe (1) into two front and rear chambers (20) and (21).
The outer peripheral surface of the other end of (7) is provided with a slidable annular protrusion (8) on the inner peripheral surface of the outer tube (17), and the other tube (12) has
Means that when the fluid flows through the pipes (1) and (12),
Communicates with the rear chamber (21) so as to flow into the rear chamber (21).
A through hole (16) is opened, and the outer tube (17) is provided with the front chamber.
A through hole (22) communicating with (20) is opened, and the interior pipe (7)
Of the one end side end surface (7a) and the annular convex portion of the inner tube (7)
(8) The expandable joint structure for a tubular body, wherein the area of the end face (7b) is set to be the same . (2) For connecting the pipes (1) and (12) so that they can expand and contract.
One end of one pipe (1) slides automatically.
And the other tube (12) is fixed to the other end
An inner pipe (7), and one of the pipes fitted outside the pipes (1) and (12).
An outer tube (17) fixed to the outer peripheral surface of the body (1), and
The inner peripheral surface of the outer tube (17) and the inner tube (7) and the other tube
Formed between the outer peripheral surface of the body (12) and the end surface of one of the tubular bodies (1)
The interior is to divide the space (19) into two rooms (20) and (21)
The outer circumference of the other end of the pipe (7) slides on the inner circumference of the outer pipe (17).
Is provided with an annular projection (8), and the other tubular body (12)
When the fluid flows through the pipes (1) and (12),
Communicate with the rear chamber (21) so as to flow into the rear chamber (21);
Through hole (16) is opened, and the outer tube (17) is
A through hole (22) communicating with the chamber (20) is opened,
The area of one end side end face (7a) of (7) is annular convex of the inner pipe (7).
The area is smaller than the area of the end face (7b) of the part (8)
A telescopic joint structure for a tubular body. 3. The expandable joint structure for a tube according to claim 1, wherein the other tube (12) and the inner tube (7) are integrally formed.