JPH0444155B2 - - Google Patents

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a pipe joint.

[Background technology]

2. Description of the Related Art Conventionally, a joint as shown in FIG. 6 has been used as a joint for piping through which water or the like passes. This pipe joint consists of a cylindrical joint body 1, a cap nut-shaped socket member 2 screwed into the end of the joint body 1, and a grip ring 3.
It is equipped with This grip ring 3 has its own outer circumferential surface, or tapered surface 3a, aligned with the inner circumferential surface, or tapered surface 1a, of the end of the joint body.
When the socket member 2 is screwed into the end of the joint body 1, the washer 4 presses the grip ring 3 in the axial direction, and this pressing force causes the grip ring 3 to connect with the tapered inner end surface of the joint body 1 and the outer peripheral surface of the pipe P. It is shaped like a wedge to fit into the gap between the two.

As a result, the end of the pipe P inserted into the joint body 1 is gripped and held so that it does not come off.
The grip ring 3 also serves as a gasket to prevent water from entering from the outside.

By the way, in this pipe joint, the tapered surfaces 1a, 3a have a slope that gradually increases in diameter in the direction in which the pipe P is pulled out, so that when the pipe P moves in the direction in which it is pulled out, it is difficult to hold the pipe P. There was a problem in that the force loosened and the tube P became easier to pull out.

[Purpose of the invention]

In view of the above circumstances, it is an object of the present invention to provide a pipe joint that does not loosen even when the pipe is moved in the drawing direction, but rather has a stronger grip.

[Disclosure of the invention]

In order to achieve the above object, the present invention provides a cylindrical joint body through which a pipe end is inserted, and a cylindrical socket member concentrically and releasably coupled to the axial end of the joint body. a grip ring disposed within the socket member so as to fit on the outside of the end of the pipe to be inserted; and a grip ring disposed within the socket member so as to fit on the outside of the end of the pipe to be inserted. A spring is provided between the joint body and the grip ring, and the inner circumferential surface of the socket member and the outer circumferential surface of the grip ring are tapered surfaces whose diameters gradually become smaller as they move away from the joint body, The grip ring is in the form of a discontinuous ring and can expand and contract in diameter, the spring always biases the grip ring in a direction away from the joint body, and the inner peripheral surface of the grip ring has a circumferential surface. A protruding part is formed along the direction, and when the grip ring moves in a direction away from the joint body and reduces its diameter by rubbing against the inner circumferential tapered surface of the socket member, this protruding part The main feature is a pipe fitting that bites into the end of the pipe.

Hereinafter, the present invention will be explained in detail with reference to the drawings showing embodiments thereof.

FIG. 1 shows an embodiment of a pipe joint according to the present invention in half section. This pipe fitting is
As shown in the figure, it includes a joint body 10, a socket member 20, and a grip ring 30. Joint body 10
is formed into a cylindrical shape, and its axial end is a tube insertion hole 11, through which the end of the tube P is inserted. The inner peripheral part of the joint body 10 has packing grooves 12, 12 near both ends in the axial direction.
A waterproof packing 13 having a horizontal V-shaped cross section in its natural state is fitted into each packing groove 12. The waterproof packing 13, 13 is
The joint body 10 and each pipe P are crimped onto the outer peripheral surface near the end of each pipe P inserted from both ends of the joint body 10.
The function is to prevent water leakage between the pipes. A protrusion 14 is provided on the outer circumferential portion of the joint body 10 at an intermediate position in the axial direction, and male screw portions 15 are formed on the outer circumferential surface of both ends in the axial direction. A cylindrical socket member 20 is screwed into each male threaded portion 15 via a respective female threaded portion 21 .
That is, the socket member 20 is concentrically and releasably coupled to the joint body 10. By changing the degree of screwing, the socket member 20 can be moved back and forth into the joint body 10.
In each socket member 20, the inner circumferential surface of the base portion 22 in which the female threaded portion 21 is formed is a straight surface, and the inner circumferential surface of the portion 23 beyond that portion gradually decreases in diameter as it moves away from the joint body 10 in the coupled state. The tapered surface 24 becomes smaller. The tube P to be inserted
the socket member 2 so as to fit on the outside of the end of the
0, a grip ring 30 is provided. That is, the grip ring 30 is provided so as to be located between the inner circumferential tapered surface 24 and the outer circumferential surface of the pipe P. The grip ring 30 is
It has a discontinuous ring shape whose overall cross section is approximately wedge-shaped, and its diameter can be expanded or reduced by the action of the notches 33. The outer peripheral surface of the tapered surface 31 is a tapered surface whose diameter gradually decreases as it moves away from the joint body 10 in the coupled state, and has the same slope as the tapered surface 24. However, this slope may also be different. As a result, it always comes into contact with the inner circumferential tapered surface 24 of the socket member 20. A projecting portion 32 extending in the circumferential direction is formed on the inner circumferential surface of the grip ring 30 so as to be in contact with the outer circumferential surface of the pipe P. In this embodiment, the grip ring 30 has a shape in which one ring is divided into three parts each having an angle of 120 degrees with three notches 33, as shown in FIG. 2a. A groove 35 along the circumferential direction is formed on the outer peripheral surface of the piece 34,
The partially open spring ring 36 fits into these grooves, so that each of the divided pieces 34 comes together to form a single discontinuous ring. A conical coil-shaped repulsion spring 40 is interposed between the end face of the grip ring 30 and the end face of the joint body 10 in such a manner that it fits on the outside of the end of the pipe P to be inserted. The force constantly pushes the grip ring 30 back away from the joint body 10. Since the frictional force between the gripping ring 30 and the pipe P is greater than the frictional force between the gripping ring 30 and the socket member 20,
When the tube P attempts to move in the withdrawal direction, the grip ring 30 follows the movement of the tube P. Therefore, at least one of the force of the repulsion spring 40 and the frictional force between the grip ring 30 and the pipe P causes the grip ring 30 to move toward the joint body 10.
The protruding portion 32 bites into the outer circumferential surface of the pipe P as it rubs against the inner circumferential tapered surface 24 of the socket member 20 to reduce its diameter. As a result, the grip ring 30 strongly grips the pipe P and prevents the pipe P from coming off. When the socket member 20 is removed, the gripping force of the grip ring 30 that has bitten into the outer peripheral surface of the pipe P is loosened, and the pipe P can be removed from the inside of the joint body 10.

By the way, as shown in Figures 1 and 3,
A fitting groove 16 is formed in the inner peripheral portion of the joint body 10 at an intermediate position in the axial direction, and a pipe stopper ring 50 is fitted into the fitting groove 16. As shown in FIG. 2b in its natural state, this pipe stopper ring 50 is provided with a mounting ring portion 51 on its outer circumference that fits and fits into the fitting groove 16. On the inner peripheral side of this mounting ring portion 51,
A protruding support ring portion 52 is integrally provided so as to be perpendicular to the ring portion 51 . From the inner peripheral side end of the support ring part 52, the mounting ring part 51
A pair of left and right packing parts 53, 53 are integrally provided, each having a base part that spreads from side to side parallel to the other, and a tip part that spreads outward in a wing shape from each base part at an angle of approximately 45 degrees. ing. The pipe stopper ring 50 is made of a soft elastic material such as rubber or resin.

During use, a pipe stopper ring 50 and a pair of waterproof gaskets 13, 13 are fitted into the interior of the joint body 10, and socket members 20, 20 each having a repulsion spring 40 and a grip ring 30 installed inside the joint body 10 are fitted at both ends.
are screwed together. Before the tube P is inserted, the grip ring 30 is positioned inside the distal end of the socket member 20 by the repulsion spring 40 and is on standby. The waterproof gasket 13 has a horizontal V-shape and a portion thereof projects into the tube insertion hole 11, and the gasket portion 53 of the tube stop ring 50 is in an extended state. When the pipe P is inserted, its outer peripheral surface slides against the protrusion 32 of the grip ring 30, but since the grip ring 30 can move a little toward the joint body 10 against the elasticity of the repulsion spring 40, the pipe P The grip ring 30 can be inserted until its end surface touches the pipe retaining ring 50, and in this state, the grip ring 30 is wedged between the inner tapered surface 24 of the socket member 20 and the outer peripheral surface of the pipe P by the elastic force of the repulsion spring 40. The inner circumferential projecting portion 32 bites into the outer circumferential surface of the pipe P.

When the pipe P is a corrosion-resistant steel pipe, as shown in FIG. 3, the pipe P is provided with anti-corrosion layers b, b on the inner and outer peripheral surfaces of the metal base a, as shown in FIG. Since this layer b is softer than the base material a, the protruding portion 32 of the grip ring 30 made of a hard material easily bites into this layer b and holds the pipe P strongly.

The end face c of the pipe P strongly abuts against the packing part 53 of the pipe stop ring 50 due to the pushing force applied to the pipe P, and is bent and press-contacted so as to make surface contact.
As a result, the packing part 53 is attached to the support ring part 52.
The pipe P is bent into a U shape supported by
It is parallel to the end face c of and is in close contact with it. Therefore, water or the like flowing inside the pipe P is prevented from reaching the packing 13 from the pipe end outward. Patsukin 13
Of course, it has a water leakage prevention effect, but the primary water leakage prevention effect at the packing part 53 of the pipe stop ring 50 provides a complete water leakage effect. That is, the pipe stopper ring 50 also has a sealing function between the inside of the pipe P and the outside of the joint, and together with the waterproof packing 13, it also contributes to improving the sealing performance between the inside and outside.

The packing portion 53 of the pipe retaining ring 50 exerts a repulsive force, which constantly urges the pipe P in the direction of removal.This further increases the wedge connection of the grip ring 30, and the It acts to further increase the holding power. The packing part 53 is
Since it has soft elastic properties, its deformation can be followed; therefore, even if the tube end surface c is not perpendicular to the axis, such as by being cut diagonally to the axis, or is roughly processed, It always adheres reliably to the entire end surface c and exhibits a water-melt effect.

The pipe stopper ring 50 was made entirely of one kind of soft elastic material, but as shown in FIG. It is also possible to form the pipe into an E-shaped pipe stop ring 50' as a whole. Packing portion 53' of this pipe stop ring 50'
When the tube end surface c is strongly applied to the tube end surface c, the tube bulges as shown in FIG. 5, and the repulsive force causes the tube end surface c to come into close contact with the tube end surface c.

In the above embodiment, the pipe joint according to the present invention is
Although shown as connecting two tubes, it goes without saying that the tube may be configured as connecting something other than a tube, such as a box.

〔Effect of the invention〕

As described above, the pipe joint according to the present invention includes a cylindrical joint body into which the pipe end is inserted, and a cylindrical joint body which is concentrically and releasably coupled to the axial end of the joint body. a socket member; a grip ring disposed within the socket member so as to fit on the outside of the end of the pipe to be inserted; and a grip ring disposed within the socket so as to fit on the outside of the end of the pipe to be inserted; Each member includes a spring disposed between the joint body and the grip ring, and the inner circumferential surface of the socket member and the outer circumferential surface of the grip ring have the same tapered surface whose diameter gradually decreases as the distance from the joint body increases. At the same time, the grip ring is in the form of a discontinuous ring so that its diameter can be expanded or contracted, and the spring always biases the grip ring in a direction away from the joint body, and the grip ring is A protrusion along the circumferential direction is formed on the inner peripheral surface,
When the grip ring moves in a direction away from the joint body and reduces its diameter by rubbing against the inner circumferential tapered surface of the socket member, the protruding portion bites into the end of the pipe to be inserted. Therefore, when a force is applied to the tube in the direction of pulling it out, the grip ring tightens the tube's outer periphery, increasing the gripping force and preventing it from weakening.

[Brief explanation of drawings]

Fig. 1 is a half-sectional view showing an embodiment of the pipe joint according to the present invention, Fig. 2a is a perspective view showing its grip ring, and Fig. 2b is an enlarged view showing the pipe stop ring in its natural state. 3 is a sectional view illustrating the action of the pipe stop ring; FIG. 4 is a sectional view showing another pipe stop ring in its natural state; FIG. 5 is a sectional view showing its action; The figure is a half-sectional view showing a conventional pipe joint. DESCRIPTION OF SYMBOLS 10... Joint body, 20... Socket member, 24... Tapered surface, 30... Grip ring, 31... Tapered surface,
40... Spring, 50, 50'... Pipe stop ring,
53, 53'...Packing part, P...Pipe.

Claims (1)

[Scope of Claims] 1. A cylindrical joint body through which the pipe end is inserted, a cylindrical socket member concentrically and releasably coupled to the axial end of the joint body, and a cylindrical socket member through which the pipe end is inserted. a grip ring disposed within the socket member so as to fit on the outside of the pipe end to be inserted; and a grip ring disposed within the socket member so as to fit on the outside of the pipe end to be inserted; a spring disposed between the grip rings, the inner circumferential surface of the socket member and the outer circumferential surface of the grip ring are tapered surfaces whose diameters gradually become smaller as they move away from the joint body, and the grip ring is free. The grip ring has the shape of a continuous ring and can expand and contract in diameter, and the spring always urges the grip ring in a direction away from the joint body, and the grip ring has a protrusion along the circumferential direction on its inner circumferential surface. A shaped part is formed, and when the grip ring moves in a direction away from the joint main body and reduces its diameter by rubbing against the inner circumferential tapered surface of the socket member, this protruding part is formed at the end of the pipe to be inserted. A pipe fitting that bites into the body. 2. A grip spring has a ring that is divided into parts, and grooves are formed along the circumferential direction on the outer circumferential surface of each divided piece, and the spring ring, which is partially open, fits into these grooves. 2. The pipe joint according to claim 1, wherein the divided pieces are brought together to form a single discontinuous ring. 3 A pipe stopper ring is provided inside the joint body along its inner peripheral surface, and a packing part along the circumferential direction is formed on the inner peripheral part of the ring, and this packing part is inserted through the pipe. 3. The pipe joint according to claim 1, wherein the pipe joint is adapted to come into pressure contact with the end surface of the pipe end. 4 Inside the joint body, a groove is provided along the inner peripheral surface, and in the groove there is a sideways V in the natural state.
According to any one of claims 1 to 3, a packing having a cross section of a square shape is fitted, and the packing is adapted to press against the outer circumferential surface of the end of the pipe to be inserted. pipe fittings.