JPH06159565A - Coming-off preventive pipe joint - Google Patents

Abstract

PURPOSE:To provide a pipe joint for surely preventing coming-off of a connected pipe from a socket. CONSTITUTION:An annular projection 12 provided with an inclined surface 121 whose diameter is contracted toward an opening side from an inner side is equipped in an inner circumferential surface of a socket 11, and an annular groove 13 adjacent to the annular projection 12 is equipped on the opening side. A locking part 22 of a rubber ring 2 is fitted into the annular groove 13, and a coming-off preventive piece 3 is embedded in an inner circumferential surface of a pressing part 21 so that the pressing part 21 bent toward an inner side of the socket 11 may be brought into contact with the inclined surface 121. Consequently, coming-off of the connected pipe is surely prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint capable of preventing a pipe to be connected from coming out of a joint portion when the pipe to be connected is connected via a seal packing.

[0002]

2. Description of the Related Art In Japanese Unexamined Patent Publication No. 57-40192, a rubber ring is attached to an annular groove provided on the inner peripheral surface of a receptacle, and a connected pipe inserted into the receptacle is expanded and contracted via the rubber ring. Flexible joints have been proposed.

[0003]

This pipe joint prevents the rubber ring from slipping out of the receptacle by embedding a coil spring in the rubber ring to increase the rigidity. Only by increasing the rigidity of the ring, it was not possible to prevent the pipe to be connected from coming out of the receiving port.

The present invention has solved the above problems and provides a pipe joint capable of reliably preventing the pipe to be connected from coming out of the receiving port.

[0005]

SUMMARY OF THE INVENTION According to the present invention, an annular projection having a wedge-shaped cross section having an inclined surface whose diameter is reduced from the inner side toward the opening side is provided on the inner peripheral surface of the receptacle, and the annular projection is adjacent to the annular projection. An annular groove is provided on the opening side, and the retaining portion of the rubber ring is fitted into the annular groove. Further, a retaining piece is planted on the inner peripheral surface of the pressing portion such that the pressing portion of the rubber ring bent to the back side of the receiving port is brought into contact with the inclined surface.

[0006]

With the above construction, when the end portion of the connected pipe is inserted into the receiving port, the retaining piece planted on the inner peripheral surface of the pressing portion contacts the outer peripheral surface of the end portion of the connected pipe. Then, when the connected pipe moves toward the opening side of the receiving port and tries to escape, the pressing portion rides on the inclined surface to reduce the diameter, and the retaining piece implanted on the inner peripheral surface of the connected portion is the end of the connected pipe. Press into the outer peripheral surface of the part so as to bite into it.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a sectional view of a pipe joint showing an embodiment of the present invention,
2 is a sectional view showing a state in which a pipe to be connected is connected to the pipe joint shown in FIG. 1, and FIGS. 3 and 4 are sectional views showing another embodiment of the present invention, in which 1 is cast iron or the like. 2 is a joint body made of metal, 2 is a rubber ring made of an elastic body such as rubber, and 20 is a seal packing.

First, the structure of the pipe joint shown in FIG. 1 will be described. The joint body 1 has an enlarged diameter receiving port 11 at one end,
A male screw 14 is provided at the other end. The inner peripheral surface of the joint body 1 on the side where the male screw 14 is provided is covered with a synthetic resin layer 4 of vinyl chloride resin, polyethylene or the like, and extends from the synthetic resin layer 4 and the inner peripheral surface of the receiving port 11 is extended. And a tubular body 41 having a predetermined distance therebetween.
The outer peripheral surface of the tubular body 41 is formed to have substantially the same diameter as the inner diameter of the connected pipe 5, and when the end of the connected pipe 5 is inserted between the tubular body 41 and the receiving port 11, The inner peripheral surface of the end portion of the connected pipe 5 is in close contact with the outer peripheral surface of the tubular body 41.

On the inner peripheral surface of the receiving port 11 of the joint body 1, there is provided an annular projection 12 having a wedge-shaped cross section having an inclined surface 121 whose diameter decreases from the back side toward the opening side.
An annular groove 13 is provided adjacent to No. 2 on the opening side. On the other hand, the rubber ring 2 is composed of a pressing portion 21 and a hook portion 22, and the hook portion 22 is fitted in the annular groove 13 to prevent the rubber ring 2 from moving. Then, the pressing portion 21 of the rubber ring 2 bent to the inner side of the receiving port 11 is formed on the inclined surface 1.
The spherical retaining members 3 are provided on the inner peripheral surface of the pressing portion 21 at predetermined intervals along the circumferential direction. The retaining piece 3 is preferably made of a material having rigidity such as cast iron, copper alloy, hard synthetic resin or the like.

Further, the receptacle 11 is provided adjacent to the annular groove 13.
An annular groove 13a is provided on the opening side of the annular groove 1a.
A seal packing 20 is attached to 3a. Incidentally, FIG.
Although the seal packing 20 having a lip portion is illustrated as an example, a seal packing having an appropriate shape other than this can be used.

When connecting the connected pipe 5 using this pipe joint, the male screw 14 provided at the end of the joint body 1 is screwed into the female screw 63 of the other joint 6 as shown in FIG. Joint 6
Covers the inner peripheral surface of the metal tube 61 integrally with a synthetic resin layer 62, and extends from the synthetic resin layer 62 to form an internal thread 63.
Is provided with a tubular body 621 on the inner peripheral side thereof, and a synthetic resin coating the inner peripheral surface of the joint body 1 when the male screw 14 of the joint body 1 is screwed into the female thread 63 of the joint 6. Layer 4
Is closely attached to the outer peripheral surface of the tubular body 621 to be connected.

Next, the connected pipe 5 is inserted into the receiving port 11 of the joint body 1.
Insert the end of. That is, the connected pipe 5 is a cast iron pipe, a steel pipe, or another metal pipe 51 whose inner peripheral surface is integrally covered with a synthetic resin layer 52 such as vinyl chloride resin.
Is inserted into the receiving port 11, and the inner peripheral surface of the end portion is brought into close contact with the outer peripheral surface of the tubular body 41 of the joint body 1 to be connected. Then, the lip portion of the seal packing 20 is pressed against the outer peripheral surface of the end portion of the connected pipe 5 to ensure watertightness, and the retaining piece 3 of the rubber ring 2 is secured.
Touches the outer peripheral surface of the end portion. In this connected state, when the connected pipe 5 moves toward the opening side of the receiving port 11 and tries to come out, the pressing portion 21 rides on the inclined surface 121 to reduce its diameter, and the retaining piece 3 implanted on the inner peripheral surface thereof. Is pressed against the outer peripheral surface of the pipe 5 to be connected, so that the pipe 5 can be reliably prevented from coming off.

The pipe joint shown in FIG. 3 uses a rubber ring 2 in which a seal packing 20 is integrally connected to a retaining portion 22, and a wide annular groove 13 provided on the opening side of the receiving port 11. A seal packing 20 is attached to the. In addition, the pressing portion 21 of the rubber ring 2 has the inclined surface 121 of the annular protrusion 12.
The retaining portion 3 having a triangular cross section is planted on the inner peripheral surface of the pressing portion 21. Also in the case of this embodiment, the seal packing 20 is brought into pressure contact with the outer peripheral surface of the pipe to be connected to ensure water tightness as in the case of the above embodiment, and the retaining piece 3 reliably prevents the pipe to be connected from coming out.

Further, contrary to the embodiment of FIG. 3, the pipe joint shown in FIG. 4 uses a rubber ring 2 in which a seal packing 20 is integrally connected to the inner side of the pressing portion 21, The seal packing 20 is attached to the annular groove 13 a provided on the inner side of the receiving port 11 of the joint body 1. Further, the hooking portion 22 is fitted in the annular groove 13 provided on the opening end side of the receiving port 11, the pressing portion 21 abuts the inclined surface 121 of the annular protrusion 12, and the retaining piece 3 is attached to the inner peripheral surface thereof. Has been planted. Also in the case of this embodiment, the watertightness is secured by the seal packing 20, and the disconnection piece 3 reliably prevents the connected pipe from coming out.

[0015]

As described above in detail, according to the present invention, the inner peripheral surface of the receptacle is provided with the inclined surface whose diameter decreases from the inner side toward the opening side.
Since the pressing portion of the rubber ring was brought into contact with the inclined surface and a retaining piece was planted on the inner peripheral surface of the rubber ring, when the pipe to be connected tried to come out of the receiving port, the pressing portion climbed onto the inclined surface and the diameter was reduced. Since the retaining piece is pressed against the outer peripheral surface of the pipe to press it, the connected pipe can be reliably prevented from coming out.

[Brief description of drawings]

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

FIG. 2 is a cross-sectional view showing a state in which a pipe to be connected is connected to the pipe joint shown in FIG.

FIG. 3 is a sectional view showing another embodiment of the present invention.

FIG. 4 is a sectional view showing still another embodiment of the present invention.

[Explanation of symbols]

 1 joint body 2 rubber ring 3 retaining piece 11 socket 12 annular protrusion 13 annular groove 20 seal packing

Claims (1)

[Claims] 1. An annular projection (12) having a wedge-shaped cross section having an inclined surface (121) having a diameter reduced from the inner side toward the opening side is provided on the inner peripheral surface of the receiving port (11) and the annular projection (12).
An annular groove (13) is provided adjacent to the opening on the opening side, the hooking portion (22) of the rubber ring (2) is fitted in the annular groove (13), and the annular groove (13) is bent to the back side of the receiving port (11). And a retaining piece (3) is planted on the inner peripheral surface of the pressing portion (21) so that the pressing portion (21) of the rubber ring (2) is brought into contact with the inclined surface (121). Detachment prevention fitting.