JPH08145264A - Pipe joint - Google Patents

Abstract

PURPOSE: To perform reliable cutting through of the peripheral surface of a pipe by a claw arranged at a pipe holding ring when a pull-off force is exerted on a pipe coupled to a pipe joint and to sufficiently support a pull-off force, exerted on a pipe, only by the claw. CONSTITUTION: A socket 2 to allow insertion of a pipe 1 is arranged and an inside diameter expansion part 3 is formed at the end part on the pipe insertion side of the socket 2. A pipe holding ring 11, a backup ring 12, and a seal ring 6 are disposed at the inside diameter expansion part 3, in the order, from the front side in an insertion direction of the pipe 1, and a cap 7 joining in a screwed-in state with the outer peripheral surface of the socket 2 and allowing insertion of the pipe 1 is provided. A plurality of claws 14 arranged at the pipe holding ring 11 in such a state that the claws are positioned at intervals of a distance in the peripheral direction thereof and protruded obliquely toward the front side in an insertion direction of the pipe 1 and at least the tip part of each claw 14 is formed approximately in a V-shape in cross section which is radially externally protruded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint suitable for use in fluid transport of water, hot water and the like and mainly applied to plastic pipes, and more particularly to unexpected pipe joints. It effectively prevents the escape of the.

[0002]

2. Description of the Related Art A conventional technique proposed to prevent accidental withdrawal of a pipe connected to a pipe joint is disclosed, for example, in Japanese Patent Application Laid-Open No. 3-69894.

As shown in the cross-sectional view of FIG. 4, this is a socket 2 which allows insertion of a pipe 1, and this socket 2.
And an inner diameter enlarging portion 3 provided at an end portion on the pipe insertion side, and a pipe holding ring 4, a backup ring 5, and a seal ring 6 which are sequentially arranged in the inner diameter enlarging portion from the front side in the insertion direction of the pipe 1. And a cap 7 which is screwed into the socket 2 to prevent the rings from being pulled out, and which allows the pipe 1 to be inserted. The pipe holding ring 4 is provided with a gap in the circumferential direction thereof. Located
This is a pipe joint in which a plurality of claws 8 that obliquely project to the front side in the insertion direction of the pipe are provided, and the backup ring 5 is provided with a projection 9 that is inscribed in each of the claws 8.

According to this, by fully inserting the pipe 1 into the pre-assembled pipe joint through the opening of the cap 7, the pipe 1 can be easily connected to the pipe joint. When a large force in the pulling direction acts on the pipe 1 under such a connected state, the pawl 8 of the retaining ring 4 is caused to bite into the peripheral surface of the pipe 1, and the pawl 8 of the pipe 1 By preventing the warp due to the tailgating in the pulling direction at the protrusion 9 of the backup ring 5, the pipe 1 can be prevented from being pulled out.

[0005]

However, in this prior art, the claw 8 of the retaining ring 4, particularly the tip portion thereof, has a substantially arcuate shape which is convex outward in the radial direction, as illustrated in a perspective view in FIG. When the pipe 1 is connected to the joint, it is possible to reduce the insertion resistance of the pipe 1 by elastically deforming each claw 8 in the direction of escaping from the pipe 1 when the pipe 1 is connected to the joint. First, there is also a problem that the claw 8 is highly likely to be elastically deformed in the direction of escaping from the peripheral surface of the pipe even when a force in the pulling direction is applied.

On the other hand, even if the tip of the claw 8 bites into the peripheral surface of the pipe well, the claw itself has a low rigidity in the direction of the warp, and therefore the backup ring is provided with each of them in order to prevent the warp. There is a problem that it is inevitable to form the projection 9 inscribed in the claw 8 with relatively high accuracy.

The present invention has been made as a result of studies made to solve the above problems of the prior art, and the object of the present invention is to provide the claws themselves provided on the pipe retaining ring. By sufficiently increasing the rigidity, there is a slight increase in the insertion resistance of the pipe into the pipe joint, but when pulling out the pipe from the pipe joint, make sure that the tip of the claw bites into the peripheral surface of the pipe. Of nails without the help of other components.
(EN) Provided is a pipe joint which can effectively prevent warping in the pipe drawing direction.

[0008]

The pipe joint of the present invention is provided with a socket for allowing insertion of a pipe, and an inner diameter enlarging portion is provided at an end portion of the socket on the pipe insertion side, and the inner diameter enlarging portion is expanded. A pipe holding ring, a backup ring and a seal ring are sequentially arranged from the front side in the insertion direction of the pipe, and are screwed to the outer peripheral surface of the socket, for example, which also allows the insertion of the pipe. Where a plurality of claws are provided on the pipe retaining ring at intervals in the circumferential direction and project obliquely forward in the insertion direction of the pipe, at least the tip portion of each claw is provided. The V-shaped cross section is convex outward in the radial direction. More preferably, the bent portion of the claw portion having a substantially V-shaped transverse cross section is provided with a radially outward convex portion having a curved shape in the transverse cross section.

[0009]

In this pipe joint, at least the tip portions of the respective claws formed on the pipe retaining ring and projecting obliquely to the front side in the inserting direction of the pipe have a substantially V-shape that is convex outward in the radial direction. Since each claw has a cross-sectional shape, it exhibits a sufficiently high rigidity against the action of the pulling force to the pipe connected to the joint, and the claw tip reliably bites into the pipe peripheral surface. To realize.

After the bite, when a force is exerted on each of the pawls in the pipe withdrawal direction, each of the pawls has a high rigidity against warping in the pipe withdrawal direction. The curling of itself can be sufficiently prevented without the need to support the pawl by other components.

Incidentally, these things have a cross sectional shape of approximately V.
This is especially noticeable when the bent portion of the claw portion that is shaped like a letter is provided with a convex portion outward in the radial direction that is curved in the cross section, and this further increases the rigidity of the pawl. From that,
It is possible to more reliably prevent the tip of the claw from biting into the peripheral surface of the pipe, and it is possible to more effectively prevent the claw from bending back.

By the way, in this case, when the pipe is inserted into the pipe joint, the contact area between the pipe and the claw is changed to a claw having a simple V-shaped cross section under the action of the curved convex portion. As compared with the V-shaped claw, the insertion resistance when connecting the pipes can be made smaller than that of the V-shaped pawls, and as a result, the pipes can be easily connected to the pipe joint. , Work reliability and certainty will be improved.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional view showing an embodiment of the present invention, the basic structure of which is almost the same as that described in the prior art. In the figure, 1 is a pipe which is mostly made of a plastic material, 2 is a socket which is also made of a plastic material and which allows the insertion of the pipe 1, and 3 is a socket 2 end portion of the socket on the pipe insertion side. Each of the provided inner diameter enlarging portions is shown, and again, in this inner diameter enlarging portion 3, the pipe holding ring 11, the backup ring 12, and the seal ring 6 are sequentially arranged from the front side in the insertion direction of the pipe 1.

Here, as shown in the enlarged perspective view of FIG. 2 (a), the pipe retaining ring 11 and the end of the cylindrical portion 13 of the pipe retaining ring 11 on the side of the backup ring are circumferentially spaced. A plurality of claws 14 are provided that project obliquely to the front side in the insertion direction of the pipe 1 and the tip side gradually approaches the center of the ring.
It has a substantially V-shaped cross-sectional shape that is convex outward in the radial direction on the tip side from the required intermediate position. FIG. 2B shows the nail 14
It is a cross-sectional view illustrating this V-shaped claw portion 14a.
Further, here, the pipe holding ring 11 and the seal ring 6
The backup ring 12 interposed between and is composed of a flat ring-shaped member.

In order to connect the pipe 1 to such a pipe joint, the pipe holding ring 11, the backup ring 12 and the seal ring 6 are sequentially accommodated in the enlarged inner diameter portion of the socket 2 as shown in the drawing. It is performed by inserting the pipe 1 from the opening provided in the central portion of the socket 2 under the state where the cap 7 sufficiently screwed to the outer periphery of the socket 2 prevents the socket 2 from being pulled out.

In this case, each claw 1 of the pipe holding ring 11
4 is a pipe 1 which is elastically expanded and deformed from its base end position.
While the pipe 1 is advanced to the required position of the inner diameter enlarging portion 3 while being sufficiently restrained from being deformed by the collared sleeve 15 which is preferably inserted at the distal end of the pipe 1.

After the connection of the pipe 1 is completed, a force in the drawing direction acts on the pipe 1,
As a result, when the pipe 1 is displaced to some extent in the drawing direction, each claw 14 exhibits high rigidity based on the existence of the V-shaped bent portion, and the claw 14 escapes to the cylindrical portion side. It will surely bite into the outer surface of the pipe without fear of deformation, and thereafter, each claw 14 will sufficiently support the force in the pulling direction under its own high rigidity, and the claw 14 will be supported. Withdrawal can be effectively prevented. That is, nail 1
4 is provided with a V-shaped bent portion so that the nail 14
The rigidity of the claw is increased, and the warp of the claw that is accompanied by the pipe 1 can be sufficiently prevented only by the rigidity of the claw itself.

Therefore, here, the rigidity of the pawl 14, particularly the tip end portion, is increased, so that the tip of the pawl 14 can be surely bited into the peripheral surface of the pipe when a force in the drawing direction is applied to the pipe 1. In addition, the backup ring 12 can sufficiently support the pulling-out force acting on the pipe 1 by the claws themselves without the need to provide a protrusion for inwardly contacting each claw 14 and preventing the claw 14 from bending back. You can

FIG. 3 is a diagram showing an example of changing the shape of the claws,
This is because when the claw 24 is provided with a bent claw portion 24a having a substantially V-shaped cross section, the claw portion 24 is formed.
As is apparent from FIG. 3B, the bent portion of a is provided with a convex portion 24b which has a curved shape in the cross section and which projects outward in the radial direction.

According to this claw 24, its rigidity against a force in each direction can be increased by the above-mentioned claw 14, so that the tip of the claw is more reliably bited into the peripheral surface of the pipe, and at the same time, It is possible to sufficiently counter a larger force acting on the pipe 1 in the pull-out direction.

In addition, according to the claw 24, the pipe 1
When inserting into the joint, it is possible to effectively avoid contact of the inner surface of the convex portion 24b with the peripheral surface of the pipe.
The contact area between the claw 24 and the peripheral surface of the pipe can be made smaller than that of the claw 14 described above, and the insertion resistance can be reduced. Therefore, the connection of the pipes 1 can be facilitated, and the reliability and reliability of the connection work can be greatly improved.

Although the present invention has been described based on the illustrated examples, it goes without saying that the high-rigidity claws 14 and 24 according to the present invention and the projection of the backup ring described in the prior art can be used together. In this case, even if an unexpectedly large pulling force acts on the pipe 1, the claws 14,
The curling of 24 can be sufficiently prevented.

[0023]

As described above, according to the present invention, in particular, at least the tip portion of each pawl provided on the pipe holding ring has a substantially V-shaped cross-sectional shape which is convex outward in the radial direction. This increases the rigidity of the pawl against forces in each direction, and ensures that the pawl bites into the pipe peripheral surface.
Further, the pulling force acting on the pipe can be sufficiently supported only by the claw. Therefore, it is possible to sufficiently eliminate the risk of accidental water leakage or the like due to a defective bite of the nail on the peripheral surface of the pipe, and to simplify the shape of the backup ring to greatly reduce the cost of the backup ring. be able to.

[0024] Here, in the case where the bent portion of the claw portion bent in a substantially V shape is provided with a convex portion outward in the radial direction, the rigidity of the claw can be further enhanced. Besides, it is possible to effectively reduce the insertion resistance of the pipe into the joint.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 shows a pipe retaining ring.

FIG. 3 is a diagram showing another example of claws provided on the pipe holding ring.

FIG. 4 is a cross-sectional view showing a conventional example.

FIG. 5 is a perspective view showing a conventional pipe retaining ring.

[Explanation of symbols]

 1 Pipe 2 Socket 3 Inner Diameter Enlarged Part 6 Seal Ring 7 Cap 11 Pipe Holding Ring 12 Backup Ring 13 Cylindrical Part 14, 24 Claw 14a V-Shaped Claw Part 24a Bent Claw Part 24b Convex Part

Claims (2)

[Claims] 1. A socket for allowing insertion of a pipe,
In this socket, the inner diameter enlarged portion provided at the end portion on the pipe insertion side, the pipe holding ring, the backup ring and the seal ring, which are sequentially arranged in the inner diameter enlarged portion from the front side in the insertion direction of the pipe, It has a cap that is screwed to prevent the rings from being pulled out, and that allows the insertion of the pipe. The pipe holding ring is located at intervals in the circumferential direction and is located on the front side in the insertion direction of the pipe. A pipe joint in which a plurality of claws projecting obliquely are provided, and at least a tip portion of each claw has a substantially V-shaped cross-sectional shape that is convex outward in the radial direction. 2. The pipe according to claim 1, wherein a bent portion of the claw portion having a substantially V-shaped cross section is provided with a radially outward convex portion having a curved shape in the cross section. Fittings.