JPS6376983A - Release preventive pipe joint - 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] Industrial applications The present invention relates to a detachment prevention pipe joint.

2. Description of the Related Art In one of the conventional detachment prevention pipe joints, the insertion port of the mating pipe is inserted into the socket of one of the shells via an annular sealing material, and the U (! An inner tapered surface that gradually expands in diameter toward the direction is formed, and between this inner tapered surface and the outer surface of the socket, an outer peripheral surface that is in contact with the inner tapered surface and an inner peripheral latching blade that is in contact with the outer surface of the socket. Some pipe joints are equipped with a circumferentially split lock ring that has a lock ring that is split in the circumferential direction.When the insertion port is passed through the lock ring in the direction of locking the inner circumference of the lock ring,
The lock ring expands slightly in diameter elastically, and applies a diameter-reducing force as a restoring force to the inner circumferential retaining blade. Therefore, the inner circumferential retaining blade hugs the outer surface of the socket. When a pull-out force is applied to the joint, the outer circumferential surface of the lock ring is pressed against the inner circumferential tapered surface of the socket, and a strong diameter-reducing force is generated on the lock ring due to the wedge action of the inner circumferential tapered surface. Therefore, the inner circumferential retaining blade bites into the outer surface of the socket and prevents the joint from coming off.

Problems to be Solved by the Invention However, according to the above-mentioned conventional configuration, there is a risk that the inner circumferential retaining blade of the lock ring will not be able to fully hug the outer surface of the socket due to dimensional tolerances in the lock ring, inner circumferential tapered surface, etc. There was a problem.

It is an object of the present invention to solve the above-mentioned conventional problems and to provide a lock ring with a sufficient grip on the socket.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides an annular seal I in which the socket of one pipe to be connected to the other pipe is inserted into the socket of the other pipe.
In the tube inserted through the tube, an inner circumferential tapered surface whose diameter gradually increases inward from the open end of the socket and an annular groove continuing to this inner circumferential tapered surface are formed on the inner surface of the socket, Between the inner tapered surface and the outer surface of the socket, there is provided a lock ring 81 that is split in the circumferential direction and has an outer circumferential surface in contact with the inner tapered surface and an inner latching blade in contact with the outer surface of the socket; An elastic ring is installed in the groove to press the lock ring against the inner tapered surface from the back surface of the lock ring.

Function: In the above configuration, the same lock ring as the conventional separation prevention pipe joint can be installed, so that the connection and separation prevention functions of the joint portion are performed in exactly the same way as in the conventional pipe joint. Moreover, even if there are dimensional tolerances in the lock ring or the inner tapered surface, the elastic ring uses its elasticity to press the lock ring from the back to the inner tapered surface.
A diameter-reducing force is generated in the lock ring, and its inner circumferential retaining blade securely and strongly hugs the outer surface of the socket.

EXAMPLE Hereinafter, an example of the present invention will be explained based on FIGS. 1 and 2.

In the detachment prevention pipe joint of this embodiment, the socket 5 of the other pipe 4 is inserted into the socket 3 of one pipe 2 to be connected to each other, and a sealing material is placed between the socket 3 and the socket 5. 6, a lock ring 7 and an elastic ring 8 are attached. The pipe 2 is a cast iron pipe whose inner surface is lined with mortar 9, and a socket 3 is formed at the connection end. The inner surface of the socket 3 has an inner peripheral tapered surface 10 whose diameter gradually increases inward from the opening end.
and an annular groove 11 following the annular groove 11 are formed, and an annular protrusion 12 and a sealing material pressure contact surface 13 are formed on the inner side thereof. An annular sealing material engaging protrusion 14 is formed on the sealing material pressing surface 13 . The pipe 4 is a rusted iron pipe whose inner surface is lined with mortar 15, and the above-mentioned insertion port 5 is formed at the connection end.

The lock ring 7 is a fully bent annular body split in the circumferential direction and has a diameter reducing force, and has an outer tapered surface 16 in contact with an inner tapered surface 10, and two inner latching blades 17. is formed in the circumferential direction and is fitted into the inner peripheral tapered surface 10. The elastic ring 8 is an annular body made of an elastic material such as rubber, and includes a curved annular suppressing portion 18 and an annular locking portion 1 on the rear surface.
9 and is formed in a cross-sectional shape, and the locking part 19 is fitted into the annular groove 11, and the end face of the suppressing part 18 presses the lock ring 7 from its back surface against the inner circumferential tapered surface 10. . Therefore, the outer peripheral tapered surface 16 of the lock ring 7 is in contact with the inner peripheral tapered surface 10, and both tapered surfaces 16.1
Due to the wedge action between 0 and 0, a diameter-reducing force is generated on the lock ring 7, and the lock ring 7 is in a state of hugging the outer surface of the insertion port 4.

A locking portion 20 in the tube axis direction is formed on the inner surface of the socket 2 between the annular groove 11 and the annular projection 12.

Further, the elastic ring 8 is integrally formed with a locking portion 19 having a triangular cross section that can come into contact with the locking portion.

In the above configuration, in order to join both tubes 2 and 4, the insertion port 5 is inserted into the socket 3 with the lock song 7, elastic ring 8, and sealing material 6 placed in the socket 3. At this time, as shown in FIG. 2, the rock song 7 is elastically deformed and slightly expanded in diameter and moved toward the back of the socket, causing the elastic ring 8 to elastically deform. At this time, the locking portion 19 of the elastic ring 8 comes into contact with the locking surface 20 &: and is compressed, thereby preventing the elastic ring 8 from falling down excessively. After the joint joining operation is completed, the lock ring 7 is pushed back forward by the restoring force of the elastic ring 8. As a result, the outer circumferential tapered surface 16 of the lock ring 7 comes into contact with the inner circumferential tapered surface 10 of the socket 3 again, and a diameter-reducing force is generated in the lock ring 7, which causes the lock ring 7, the inner circumferential tapered surface 10, etc. Even if there are dimensional tolerances, the inner circumferential retaining blade 17 reliably hugs the outer surface of the socket 5.

When a pull-out force is applied to the joint, the outer tapered surface 16 of the lock ring 7 is pressed against the inner tapered surface 10 of the socket 3, causing the lock ring 7 to undergo strong contraction due to the wedge action between both tapered surfaces 16.10. A radial force is generated.

Therefore, the inner circumferential retaining blade 17 bites into and hugs the outer surface of the insertion port 5 to prevent both tubes 2 and 4 from coming off.

As described above, the elastic ring 8 deforms freely when inserting the socket 5 into the socket 3 to allow the diameter of the lock ring 7 to expand, and after insertion, the elastic ring 8 exerts a restoring force to
is pressed against the inner circumferential tapered surface 10 to apply a diameter reducing force to the lock ring 7, thereby ensuring that the inner circumferential retaining blade 17 is held in the insertion opening 5.

Effects of the Invention As described above, according to the present invention, since the lock ring is pushed toward the inner tapered surface by the elastic ring, the lock ring's inner retaining blade is not held against the outer surface of the socket. Therefore, even if there are dimensional tolerances in the lock ring or the inner circumferential tapered surface, a reliable II release prevention function can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG. 2 is a sectional view showing the action of an elastic ring. 3... Socket, 5... Socket, 7... Lock ring,
8... Elastic ring, 10... Inner peripheral tapered surface, 11.
...Annular groove, 17...Inner peripheral retaining blade.

Claims (1)

[Claims] 1. In a pipe joint in which the socket of one pipe to be connected to the other pipe is inserted through an annular sealing material, the pipe gradually expands inward from the open end on the inner surface of the socket. An inner peripheral tapered surface having a diameter and an annular groove continuing to the inner peripheral tapered surface are formed, and an outer peripheral surface that is in contact with the inner peripheral tapered surface and an annular groove that is in contact with the socket outer surface is formed between the inner peripheral tapered surface and the socket outer surface. A detachment prevention device characterized in that a circumferentially split lock ring having an inner circumferential retaining blade is attached, and an elastic ring is attached in the annular groove to press the lock ring from its back surface to an inner circumferential tapered surface. pipe fittings.