JPS6030888A - Joint structure of fluid pipe - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a joint structure for a fluid pipe, and more specifically, a backing having a self-sealing effect in the gap between a large diameter pipe part (socket part) and a small diameter pipe part (insertion part). This invention relates to the structure of a connection between two fluid pipes that are sealed with a fluid tube.

The present applicant previously proposed in Japanese Patent Application No. 55-124111 (Japanese Unexamined Patent Publication No. 57-51088) that combines the advantages of a conventional mechanical joint that pressurizes the backing and a socket-type joint that has the same self-sealing backing. I proposed a joint. And furthermore, the patent application 1986-
No. 94559 (Japanese Unexamined Patent Publication No. 58-692, hereinafter referred to as prior art) proposed an improved joint.

FIG. 1 shows an overview of the prior art. Here, 1° is a socket part, and the inner surface of the socket part l is formed with a tapered surface 12 from the outer end 11, and a valve part abutment surface 13 following the tapered surface 12. 2 is an insertion opening, and 3 is a backing that has a self-sealing effect. Reference numeral 4 denotes a press ring, and a collar 412 is formed on the outer periphery of an end surface 411 of an arm portion 41 of the press ring 4, and the backing 3 is gripped by this collar 412. The length of the arm portion 41 of the press ring is made substantially equal to the distance from the outer end 11 of the socket portion to the back of the tapered surface 12.

The push ring 4 is tightened via the port 5. and,
This joint structure has the following effects.

・l) Since the connection is performed using a mechanical joint procedure, there is no chamfering of the tip 21 of the insertion port, and the connection operation is simple. (2) Since the backing is accommodated with plenty of room in the valve housing space 15 of the socket, there is no deterioration of the S backing. ■The flange of the press ring Ct The backing is securely held, and when the flange is tightened in a fixed position and accommodated at the back of the tapered surface of the socket, it has a centering effect.

However, in this prior art, when a negative pressure is generated inside the fluid pipe and a force is applied to suck the backing into the fluid pipe, the gripping force of the collar of the push ring and the frictional force between the inner surface of the socket and the outer circumferential surface of the socket are applied. There is a problem in that the backing cannot sufficiently resist the force that sucks the backing, resulting in an accident in which the backing is sucked into the pipe.

The present invention has been made in order to overcome the drawbacks of the above-mentioned prior art, and focuses on the effect of the tapered surface formed on the socket to create a joint that prevents the backing from slipping out and allows for better connection operations. The technical challenge is to obtain the following.

The present invention adopts the following configuration (technical means) in order to achieve the above technical problem. ■ At the connection part of the fluid pipe where the insertion part is inserted into the socket part through a self-sealing backing inserted by a push ring, ■ The inner surface of the socket part has a tapered surface and a valve from the outer end. A contact surface is formed,
■The backing consists of a valve part that is loaded into the valve part contacting surface of the socket part and a heel part that fits on the outer periphery of the flange of the push ring, and ■The push ring that is tightened by the fastener is tightened. A joint structure for a fluid pipe, characterized in that, when the backing is in a fixed position, the heel portion of the backing is sandwiched between the tapered surface of the socket and the outer circumferential surface of the collar of the press ring.

The joint structure having the above configuration is implemented by the following connection operation and operates as follows.

To connect fluid pipes to each other, first, a push ring with a backing attached to the socket is attached. During this installation, lightly tighten the fastener until the backing comes into contact with the tapered surface of the socket. (referred to as the stopped state), the push ring 2. The backing and fasteners are fixed together as a set to the receiver 1'' portion, so that they do not move inadvertently.

Next, when the fluid pipe to be connected is inserted into the socket, the fastener is tightened, and the press ring is pushed into the socket, the valve part of the backing is guided by the tapered surface and its diameter is expanded into the valve part housing part. It is being pushed in while shrinking. When the valve part is completely accommodated in the valve part accommodating part, the heel part of the backing is strongly pressed against the tapered surface of the socket part, and further pushing is stopped.

In the main joint halves where the connection has been made, the backing normally receives pressure from the fluid pipe and performs a sealing action due to its self-sealing action, but when the internal pressure of the fluid pipe becomes negative pressure, the heel of the backing The backing sufficiently resists negative pressure due to the wedge effect of the inverted triangular space that is sandwiched between the tapered surface of the socket and the arm of the push ring and formed by the tapered surface and the arm.

The joint structure of the present invention has the following unique effects.

- Since the press ring, backing, and fastener can be assembled into the socket part as one unit, they can be transported while being assembled to the socket part.

■ When inserting the socket, the backing is kept in its natural state (i.e., uncompressed state), so
The insertion port can be inserted smoothly.

- The backing can be smoothly inserted into the gap between the valve abutting surface of the socket and the outer peripheral surface of the socket by being guided by the tapered surface of the socket.

b4) The heel part of the backing is sandwiched between the tapered surface of the socket part and the arm part of the pushing ring, and the backing is strongly gripped by the wedge action of the inverted triangular space formed by them, so there is no negative impact inside the pipe. It is possible to prevent the backing from being pulled out due to pressure.

The present invention further enhances its effects by adopting the following aspects.

■ The inner diameter of the valve part of the backing must be substantially larger than the outer diameter of the insertion part in its natural state (uncompressed state).

In other words, the inner diameter of the valve part should be the same as the outer diameter of the socket, or it should be slightly larger. According to this aspect, when connecting the fluid phrenology crab, the insertion operation of the insertion port is smoothly performed without receiving resistance from the backing. Therefore, there is no need to chamfer the end face of the insertion port.

The present invention will be explained in detail below.

2 and 3 show an embodiment of the joint structure of the present invention.

l is a socket at the end of one of the fluid pipes to be connected,
A flange 11 is formed on the outer surface of the socket 1, and a tapered surface 13 whose diameter gradually decreases as it goes deeper from the outer end 12 and a straight line following the tapered surface 13 are formed on the inner surface of the socket 1. A cylindrical valve portion abutting portion 14 is formed.

Reference numeral 2 designates the insertion port of the other fluid pipe inserted into the socket 1, and the end surface 21 of the insertion port 2 is not chamfered.

3 is a backing, which consists of a valve part 31 at the front part and a heel part 32 at the rear part, and the valve part 31 is connected to the socket part l.
It is compressed and interposed in the pulp part accommodation space 15 between the valve part abutment surface 14 and the outer circumferential surface of the insertion part 2, and exerts a self-sealing action by receiving water pressure (or fluid pressure) inside the fluid pipe. The heel portion 32 is formed thick, and its outer diameter is made sufficiently larger than the minimum diameter of the tapered surface 13 of the socket portion l, that is, the inner diameter of the valve portion abutting surface 14. Further, a recessed portion 321 is formed on the inner periphery of the heel portion 32, and the recessed portion 321 is elastically fitted onto the outer periphery of an arm portion of a press ring to be described later.

Reference numeral 4 denotes an annular push ring, which has an L-shaped cross section and includes a waist portion 41 of a radial vertical member facing the outer end 12 of the socket and an axial member that enters into the tapered surface 13 of the socket. Arm part 4
It consists of 2. The push ring 4 is engaged with the socket l by inserting ports of a fastener to be described later into port through holes 43 formed at various locations in the circumferential direction. When the arm part 42 is tightened in the fixed position, it is inserted into the tapered surface 13 of the socket part at a predetermined distance and close to the inner part of the tapered surface 13, and the outer circumferential surface of the arm part 42 and the taper part of the socket part are connected to each other. A cavity having an approximately inverted triangular cross section is formed with the surface. Note that the push ring 4 is formed with an eaves portion 44 at the front thereof in a continuous manner with the bolt through hole 43, but the eaves portion 44 can be omitted as appropriate.

Reference numeral 5 denotes a fastener, which is composed of a port 51 and a nut 52, and a port 51 has a port 51 formed at its head, and is adapted to engage the port 511 with the flange it of the receiving portion. .

Next, we will discuss the procedure for connecting the joint structure on the wood flow side and the water injection action.

(1) For connection, first fit the concave portion 321 of the heel portion 32 of the backing 3 onto the outer periphery of the arm portion 42 of the push ring 4,
Attach the backing 3 to the press ring 4.

(2) Bring the press ring 4 with the backing 3 attached to face the socket l, and use the fastener 5 to engage the collar 11 of the socket 1 and the press ring 4.

(3) Rotate the nut of the fastener 5 to advance the push ring 4 into the socket l, so that the front end of the valve 31 of the backing 3 collides with the tapered surface 13 of the socket l (Fig. 3). reference). In this state, the press ring 4 with the backing 3 mounted thereon is assembled integrally with the socket l, and is in a temporarily fixed state.

(4) Next, insert the insertion tube 2 into the socket 1. At this time, if the inner diameter of the valve portion 31 of the backing 3 is substantially equal to or slightly larger than the outer diameter of the insertion tube 2, the insertion of the insertion tube 2 can be performed more smoothly.

(5) After tightening, rotate the nut 52 of the fastener 5 to push the press ring 4 further into the socket l. At this time, the valve 31 of the backing 3 is guided by the tapered surface 13 of the socket part 1 and enters into the valve part contact surface 14.
As the press ring 4 is pushed in, the heel portion 32 of the backing 3 is pressed between the outer peripheral surface of the arm portion 42 of the press ring 4 and the tapered surface 13 of the socket portion 1. The press ring 4 is pushed in when the press ring 4 collides with the outer end surface 12 of the socket l, or when the heel portion 32 of the backing 3 is sufficiently compressed between the tapered surface 13 and the arm portion 42. Complete.

(6) When the pressure inside the fluid pipe acts on the joint part connected by the above procedure, the valve part 31 of the backing 3 exhibits a water resistance effect by self-sealing action. Also, when negative pressure is applied to the fluid pipe, a force is applied to the backing 3 to suck it into the pipe, but the heel part 32 of the backing 3
2, it resists the negative pressure and prevents the backing from being sucked in.

4 and 5 show an embodiment in which the joint structure of the present invention is applied to a sleeve joint device S.

Here, 6 is a cylindrical sleeve tube, and each of the sleeve tubes 6 has a socket portion with a tapered surface 13 formed at both ends. Backing 3. The structure of the push ring 4 is similar to the above embodiment. A long bolt is used as the fastener 5. The sleeve joint device S is constituted by each of the above members.

FIG. 4 shows the assembled state of this sleeve splice device S,
It is assembled in this state at the factory and delivered to the site in this state. In this assembled state, the sleeve splice device S is in a fixed state with no play as a whole, making it suitable for transportation. When the insertion port 2 (indicated by dotted lines) is inserted in this state, the inner diameter of the backing 3 is larger than the outer diameter of the insertion port 2, so the insertion operation is performed smoothly.

FIG. 5 shows the state in which the fastener 5 of the sleeve splice device S is completely tightened. That is, as the nut of the fastener 5 is rotated to tighten the press ring 4, the valve portion of the backing 3 is guided by the tapered surface 13 and pushed into the valve portion housing portion while its diameter is reduced. , and the front end surface of the waist portion 41 of the press ring 4 is aligned with the end surface 1 of the socket portion of the sleeve 6.
2, when the push ring 4 is pushed to the position where it collides with the banking 3, the heel portion 32 of the backing 3 is simultaneously sandwiched between the tapered surface 13 of the sleeve 6 and the collar 42 of the push ring, and the
is fixed.

FIG. 6 shows another embodiment of the sleeve joint device.

In this embodiment, flanges 11 are formed at both ends of the sleeve 6, and independent fasteners 5 are attached to each flanges 11.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of a conventional joint. Figure 2 and below show examples of the joint flat structure of the present invention,
FIG. 2 is a sectional view showing the tightened state of one embodiment in the fixed position, and FIG. 3 is a sectional view showing the temporarily tightened state.
4 and 5 are sectional views showing the structure of another embodiment (sleeve device), and FIG. 6 is a partially sectional view showing the structure of still another embodiment. l... Socket part 12... Outer end 13.
Tapered surface for 14... Valve part contact surface
2... Socket part 3... Backing 31
... Valve part 32 ... Heel part 4
... Push ring 42 ... Tsuba 5 ...
... Fastener patent applicant Cosmoeki Co., Ltd. Patent attorney Hitoshi Ikeda Figure 3

Claims (1)

[Claims] 1. At the connection part of the fluid pipe where the insertion part (2) is inserted into the socket part (1) via the self-sealing backing (3) inserted by the press ring (0). , the socket part (1)
A tapered surface (13) and a valve part abutting surface (14) are formed on the inner surface of the socket part (1) from the outer end (12), and the backing (3) has a valve part abutting surface (14) of the socket part (1). 14) A heel portion (fitted to the outer periphery of the valve portion (31) and the flange portion (42) of the press ring (4) to be loaded therein);
32), and when the press ring (4) is tightened by the fastener (5) and is in the fixed position, the heel part (32) of the backing (3) matches the taper of the socket part (1). A joint structure for a fluid pipe, characterized in that it is sandwiched between a surface (13) and an outer circumferential surface of a flange (42) of the press ring (4). 2. The fluid pipe according to claim 1, wherein the inner diameter of the valve part (31) of the backing (3) is substantially larger than the outer diameter of the insertion part (2) in a natural state. Joint structure.