JP3235816B2 - Captive fittings - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint having a detachment preventing function for easily connecting pipes.

[0002]

2. Description of the Related Art For connecting pipes, for example, when laying a water pipe or the like, a pipe joint comprising a combination of an insertion port of one pipe and a receiving port of the other pipe is used.

[0003] Such a pipe joint is required to have a certain degree of flexibility and elasticity in order to cope with vibration of soft ground, pressure in the pipe, and the like, in addition to a function of preventing detachment. Also,
In order to make the connection simple, it is necessary to consider the workability.

A pipe joint devised in view of these requirements is disclosed, for example, in Japanese Utility Model Publication No. 54-9610. This conventional pipe joint includes an intermediate ring formed by mounting a seal packing between inner and outer flanges of a split lock ring having an H-shaped cross section having flanges on both sides.
A projection is provided between the tube insertion and the tube socket into which this tube insertion is inserted, and a projection capable of locking one flange of the lock ring is provided on an end circumference of the tube insertion, and the other flange is locked. The push ring is attached to the end of the pipe socket.

[0005]

In the conventional pipe joint described above, the means for preventing the pipe from coming off is a projection fixed to the end circumference of the pipe, so that the insertion of the intermediate ring is troublesome, and furthermore, the pipe fitting is difficult. Since the projection must be separately fixed, the number of steps increases.

Further, since a relatively expensive push ring is used to prevent the intermediate ring from coming off, the cost of the pipe joint increases, and the push ring is fixed to the pipe socket with bolts and nuts. In addition, it takes time to connect pipes, and the work efficiency is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has a simple structure to prevent a pipe from coming off and to provide a quick-disconnect pipe coupling. The purpose is to do.

[0008]

In order to achieve the above-mentioned object, a separation-preventing pipe joint according to the present invention is provided with a receiving port formed at an open end of one pipe and a required clearance provided in the receiving port. Between the opening outer peripheral surface of the other pipe to be inserted,
A non-slip surface formed on the inner surface of the locking piece, provided with a plurality of locking pieces facing the opening end of the receiving port, and a detachment prevention ring formed by inserting a seal member into an annular groove on the inner and outer peripheral surfaces. Is interposed so as to be able to come into contact with the outer peripheral surface of the other pipe, and on the inner peripheral surface of the opening end of the receiving port, the inner surface is a tapered surface whose diameter gradually decreases toward the opening end of the receiving port. The locking ring is detachably fitted.

In this case, it is desirable that the locking ring is formed of a material which is elastically deformable and is partially cut in the circumferential direction.

[0010] It is desirable that the connecting base of the locking piece be made thin.

[0011]

The inner and outer sealing members of the detachment prevention ring inserted into the receiving opening of one pipe are pressed against the inner surface of the receiving opening and the outer surface of the other pipe to ensure watertightness. Also, when a pull-out force acts on the pipe, the plurality of locking pieces connected to the separation prevention ring are reduced in diameter by the locking ring, and the non-slip surface cuts into the outer peripheral surface of the other pipe. Prevention is achieved.

If the locking ring is formed of an elastically deformable material having a part cut in the circumferential direction, the mounting and dismounting of the locking ring is facilitated and the workability is improved.

If the connecting base of the locking piece is made thin, the flexibility of the pipe at the joint is enhanced, and the pipe can be prevented from being damaged due to vibration and ground displacement.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2, a receiving port 3 is formed at the opening end of one of the pipes 1 so that the opening end of the other pipe 2 can be inserted with a margin. An enlarged diameter cylindrical portion 4 having a required length whose inner diameter is slightly increased.

An annular groove 5 is formed in the inner and outer peripheral surfaces of the enlarged diameter cylindrical portion 4.
a and 5b are formed, and an annular detachment prevention ring 5 having a plurality (three in this embodiment) of locking pieces 6 extending in the direction of the opening end of the receiving port 3 is loosely fitted. Packings 7, 7 made of rubber or the like having elasticity are fitted in the two annular grooves 5a, 5b.

The locking pieces 6 are arranged continuously at intervals of 120 ° in the circumferential direction, and the inner surface of the arc is formed so that the insertion resistance of the pipe 2 is small and the drawing resistance is large. A non-slip surface, for example, a serrated surface 6a is formed.
The outer surface of the locking piece 6 is a tapered surface 8 whose diameter gradually decreases toward the opening end of the receiving port 3.

The detachment prevention ring 5 is brought into contact with a step 9 formed at a continuous base of the enlarged-diameter cylindrical portion 4, so that the pipe 1 is prevented from coming off.
Is prevented from moving inward.

Reference numeral 10 denotes a substantially C-shaped elastically deformable locking ring having a part cut off in the circumferential direction. 4 is fitted in a locking groove 11 formed on the inner peripheral surface of the opening end. The inner peripheral surface of the locking ring 10 is a tapered surface 12 having the same inclination as the tapered surface of the locking ring 6.

In order to connect the pipe 1 and the pipe 2, as shown in FIG. 1, the open end of the pipe 2 is inserted into the receiving port 3 of the pipe 1 to the position of the imaginary line. At this time, the packings 7, 7 provided on the inner and outer peripheral surfaces of the separation preventing ring 5 are elastically deformed, and are brought into pressure contact with the outer peripheral surface of the pipe 2 and the inner peripheral surface of the enlarged-diameter tube portion 4, so that both pipes 1 The watertightness between the two is ensured.

In the state shown in FIG.
Can bend via the separation prevention ring 5,
Workability at the time of pipe connection is good, and even if external force is applied to both pipes 1 and 2 due to soft ground or the like, breakage of the pipes and the like are prevented.

After the construction shown in FIG. 1, when a pulling-out force acts on the pipe 1 or 2 due to water pressure or the like, as shown in FIG.
The locking piece 6 has a tapered surface 8 and a locking ring 10.
Of the inner surface of the pipe 2 by forcibly reducing the diameter of the locking piece 6.
To prevent the pipe 2 from being detached.

As described above, in the above embodiment, since there is no need to provide a projection on the outer peripheral surface of the pipe 2 on the insertion side as in the prior art, it is easy to insert the separation prevention ring 5 and the man-hour is reduced. Be reduced.

Further, since the retaining ring 5 can be prevented from coming off simply by fitting the locking ring 10, it is not necessary to use an expensive pressing ring as in the prior art, and the cost of the pipe joint can be reduced.

The present invention is not limited to the above embodiment, but can take various forms. For example, as shown in an enlarged manner in FIG. 3, a thin portion 13 may be formed at the base of the engagement piece 6 in the separation prevention ring 5. By doing so, the flexibility of each locking piece 6 is improved, so that both pipes 1 and 2 can be largely bent at the joint portion.

The outer peripheral surface of the locking piece 6 may be a curved surface instead of the tapered surface 8, and the inner surface may be a rough surface other than the sawtooth surface 6a.

The number of the locking pieces 6 is not limited to three as a matter of course. A screw is formed on the outer peripheral surface of the locking ring 10, and a female screw is formed on the inner peripheral surface of the enlarged-diameter tube portion 4.
A screw connection may be used. In this case, it is not necessary to cut a part of the locking ring 10 in the circumferential direction.

[0028]

According to the present invention, it is possible to completely prevent the pipe from slipping out with a simple structure and to eliminate the need for the conventional press ring and projection, so that the pipe can be quickly connected. And an inexpensive pipe joint can be provided.

According to the second aspect, the attachment and detachment of the locking ring is facilitated, and the workability is improved.

According to the third aspect of the present invention, the flexibility of the pipe at the joint portion is enhanced, and the pipe can be prevented from being damaged due to ground displacement, vibration, or the like.

[0031]

[Brief description of the drawings]

FIG. 1 is a semi-longitudinal sectional view showing a state when a pipe is inserted according to a first embodiment of the present invention.

FIG. 2 is a semi-longitudinal sectional view showing a state at the time of exiting a pipe.

FIG. 3 is an enlarged vertical sectional view showing another embodiment of the separation bedding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 One pipe 2 The other pipe 3 Reception port 4 Large diameter cylinder part 5 Detachment prevention ring 5a Annular groove 5b Annular groove 6 Locking piece 6a Serrated surface 7 Packing 8 Tapered surface 9 Step 10 Lock ring 11 Lock groove 12 Tapered surface 13 Thin part

Continuation of the front page (56) References JP-A-55-139584 (JP, A) JP-A-58-114987 (JP, U) JP-A-58-40685 (JP, U) (58) Fields investigated (Int) .Cl. ⁷ , DB name) F16L 21/00-21/08 F16L 27/12

Claims (3)

(57) [Claims] 1. A receiving port formed at an opening end of one pipe and an outer peripheral surface of an opening of the other pipe inserted into the receiving port with a required clearance. A non-slip surface formed on the inner surface of the locking piece is provided with a detachment prevention ring formed by inserting a seal member into an annular groove on the inner and outer peripheral surfaces. A locking ring which is interposed so as to be able to contact the outer peripheral surface of the pipe and has a tapered surface whose inner surface gradually decreases in diameter toward the opening end of the receiving port is provided on the inner peripheral surface of the opening end of the receiving port. A detachable pipe fitting which is detachably fitted. 2. The detachable pipe coupling according to claim 1, wherein the locking ring is formed of an elastically deformable material having a part cut in a circumferential direction. 3. The detachable pipe joint according to claim 1, wherein the connecting base of the locking piece is made thin.