JPH10252959A - Detachment preventive joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the insertion resistance of a spigot by a rubber ring by increasing the wall thickness of the spigot over the whole expandable length at a rubber ring abutting part of the spigot to be inserted in a socket. SOLUTION: A spigot 30 consists of polyolefin similar to tubes 12a, 12b, and injection molded in a short tube shape. A flange-shaped stopper stepped part 36 is formed on a tip part of the spigot 30, and the outer surface of the tip part of the stopper stepped part is chamfered in a tapered manner. A part which is the outer surface of the spigot 30 and which is sealed by a rubber ring 24 when a joint 10 is expanded (a rubber ring abutting part 38) is increased in wall thickness over the whole length of the expansion margin and continuously in the circumference direction. The outside diameter of the stopper stepped part 36 and the rubber ring abutting part 38 is set to be equal to or slightly smaller than the inside diameter of a socket 14. Because the rubber ring 24 of large inside diameter can be used, the compression of the rubber ring 24 by the stopper stepped part 36 of the spigot 30 is reduced, the insertion resistance of the spigot 30 is reduced, and detachment of the rubber ring 24 through bending of the conduit can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-separation joint,
In particular, for example, the present invention relates to a slip-on type disengagement prevention joint that compresses a rubber ring as a sealing material when a spigot is inserted into a socket.

[0002]

2. Description of the Related Art An example of this kind of conventional separation prevention joint is as follows.
For example, it is disclosed in JP-A-4-224388.
4 has a projection 3 formed on the outer peripheral surface of the front end portion of the spout 2, and the projection 3 is engaged with a lock ring 5 arranged in the receiving port 4. 2 is prevented. When the spigot 2 is inserted into the socket 4, the rubber ring 6 arranged in the spigot 4 is compressed by the protrusion 3 of the spigot 2 so as to be spread.

[0003]

In the prior art, the problem is that the insertion resistance due to the repulsion of the rubber ring 6 when the projection 3 of the spigot 2 passes through the rubber ring 6 of the socket 4 at the time of joining is large. There was a point. In particular, in the case of a plastic tube as compared with an iron tube, it is necessary to increase the step of the projection 3 from the viewpoint of securing strength, and the insertion resistance increases.

[0004] Further, a gap is formed between the opening of the receiving port 4 and the spout 2 at least at the level difference of the projection 3. Since this gap is large, the pipe is bent at the base of the spout 2. When a force is applied, the rubber ring 6 may come off due to water pressure or the like. Therefore, the main purpose of this invention is to
An object of the present invention is to provide a separation prevention joint capable of reducing insertion resistance of a spigot formed by a rubber ring.

[0005]

According to the present invention, there is provided a receiving port, a rubber ring receiving section provided in the receiving port, a rubber ring received in the rubber ring receiving section, and a rubber ring provided on the back side of the rubber ring of the receiving port. A ring accommodating portion, a lock ring accommodated in the ring accommodating portion, a spigot inserted into the socket, and a lock ring formed on the outer peripheral surface of the spigot and located further back than the lock ring. A detachment prevention joint comprising a stopper stepped portion to be stopped and a rubber ring contact portion sealed by a rubber ring, characterized in that the rubber ring contact portion is made thicker over the entire length of expansion and contraction. is there.

[0006]

[Action] By making the rubber ring contact portion on the outer surface of the spigot sealed by the rubber ring thick over the entire length of the expansion and contraction margin,
Use a rubber ring with a larger inside diameter than before. Therefore, the amount of compression of the rubber ring by the stopper step of the spigot during joining is reduced. Further, the gap between the opening of the receiving port and the port can be narrowed.

[0007]

According to the present invention, the amount of compression of the rubber ring by the stopper step of the spigot at the time of joining is reduced, so that the insertion resistance of the spigot can be reduced. Further, since the gap between the opening of the receptacle and the spigot can be narrowed, the rubber ring can be prevented from coming out of the gap by water pressure even if a force to bend the pipe acts on the base of the spigot.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A detachment prevention joint 10 of this embodiment shown in FIG.
Is for connecting the pipes 12a and 12b made of a polyolefin resin such as polyethylene or polypropylene to each other.
Including a port 14 made of the same polyolefin resin as b and injection-molded.

The receiving port 14 includes a short tube portion 16 having the same tube diameter as the tube 12a, and is formed by expanding the diameter from the end of the short tube portion 16 toward the opening. A rubber ring accommodating portion 20 is formed on the opening end side of the inner surface of the receiving port 14, and a ring accommodating portion 22 is formed on the inner side of the rubber ring accommodating portion 20. The rubber ring 24 is accommodated in the rubber ring accommodating portion 20 and the ring accommodating portion 22 is accommodated.
With the centering member 26 and the lock ring 28 housed therein, the spigot 30 is inserted into the receptacle 14.

The centering member 26 is for aligning the center of the lock ring 28 with the center axis of the socket 14.
It is made of an elastic material such as rubber and formed in a ring shape. The outer diameter of the centering member 26 is set to substantially the same size as the bottom diameter of the ring accommodating portion 22, and the inner diameter is
8 is set to the same size as the outer diameter. The lock ring 28 is formed in a substantially C-ring shape from a metal such as stainless steel, and the inner surface of the lock ring 28 at one axial end is chamfered in a tapered shape. The side on which the tapered surface is formed is directed toward the opening end of the receiving port 14. The inner diameter of the lock ring 28 is set to a size substantially equal to or smaller than the outer diameter of the inserted spigot 30.

The spigot 30 is made of the same polyolefin resin as the tubes 12a and 12b, and is injection-molded into a short tube. A flange-shaped stopper step 36 is formed at the tip of the spigot 30, and the outer surface of the tip of the stopper step 36 is chamfered in a tapered shape. The portion of the outer surface of the spigot 30 which the rubber ring 24 seals when the joint 10 expands and contracts (hereinafter referred to as “rubber ring contact portion 38”) is continuous over the entire length of the expansion and contraction margin and in the circumferential direction. And increase the meat. Here, the outer diameters of the stopper stepped portion 36 and the rubber ring contact portion 38 correspond to the receiving port 14.
Is set to be equal to or slightly smaller than the inner diameter of.

A reinforcing member 40 is inserted into the inner surface of the spigot 30 corresponding to the stopper step 36. Reinforcement 40
Is formed in a short tube with a material that is difficult to deform, such as stainless steel, BC6, or polyacetal. The outer diameter of the reinforcing member 40 is set to a size slightly larger than the inner diameter of the spigot 30 in order to prevent the reinforcing material 40 from being detached from the spigot 30. The reinforcing member 40 can be formed by insert molding.

When connecting the pipes 12a and 12b,
As shown in FIG. 1, the short tube portion 16 of the receiving port 14 is butt-fused to the tube 12a, and the spigot 30 is butt-fused to the tube 12b such that the stopper stepped portion 36 is disposed on the distal end side. Next, the spigot 30 connected to the pipe 12b is inserted into the socket 14.
Then, the stopper step 36 of the spigot 30 is passed through the inner surfaces of the rubber ring 24 and the lock ring 28 so that the lock ring 2
8 and a position where the receiving port 14 inclines toward the short pipe portion 16.

At this time, the diameter of the rubber ring 24 and the lock ring 28 can be increased by the tapered surface formed on the outer surface of the distal end portion of the stopper step 36, so that the spigot 30 can be inserted smoothly. Further, the rubber ring contact portion 38 of the spigot 30 is made thick, and the rubber ring 24 having an inner diameter larger than that of the conventional one can be used accordingly. The amount of compression is reduced, and the insertion resistance of the spigot 30 can be reduced.

After the connection, when a force for detaching the spigot 30 from the receptacle 14 acts on the conduit, as shown in FIG.
The stopper step 36 is locked by the lock ring 28 to prevent the spout 30 from being detached from the receptacle 14. At this time, a force that reduces the diameter from the lock ring 28 and the rubber ring 24 acts on the spigot 30, but the spigot 30 is reinforced by the reinforcing member 40 and the thickened rubber ring abutting portion 38. There is no danger of diameter reduction. Conversely, FIG. 3 shows a state in which a force for inserting the spigot 30 into the receptacle 14 acts on the duct, and the spigot 30 is inserted to the deepest part of the receptacle 14.

As can be seen from FIG. 2 and FIG.
Since the rubber ring contact portion 38 of 0 is thickened over the entire length of the expansion and contraction allowance, the sealing property of the rubber ring 24 to the spout 30 is not impaired within the range of the expansion and contraction allowance. Similarly, the gap between the opening of the receiving port 14 and the spigot 30 can always be narrowed by the rubber ring abutting portion 38. Therefore, even if a force that bends the conduit at the base of the spigot 30 acts, 24 can be prevented from slipping out of this gap due to water pressure or the like.

As described above, according to this embodiment,
By making the rubber ring abutting portion 38 of the spigot 30 thick over the entire length of the expansion and contraction margin, the insertion resistance of the spigot 30 can be reduced, and the rubber ring 24 can be prevented from coming off due to bending of the conduit.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;

FIG. 2 is an illustrative view showing a state in which a force for detaching the spout from the receptacle acts in the embodiment of FIG. 1;

FIG. 3 is an illustrative view showing a state where a spigot is inserted to a deepest part of a receiving port in the embodiment of FIG. 1;

FIG. 4 is an illustrative view showing a conventional technique;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Separation prevention joint 14 ... Receptacle 20 ... Rubber ring accommodating part 22 ... Ring accommodating part 24 ... Rubber ring 26 ... Centering member 28 ... Lock ring 30 ... Spout 36 ... Stopper step 38 ... Rubber ring contact part 40 … Reinforcing material

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Maki 3-3-1, Nihonbashi-Muromachi, Chuo-ku, Tokyo Kubota Tokyo Head Office

Claims (1)

[Claims] 1. A receiving port, a rubber ring receiving section provided in the receiving port, a rubber ring stored in the rubber receiving section, and a ring receiving section provided in the receiving port at a position deeper than the rubber ring. When,
A lock ring accommodated in the ring accommodating portion, a spigot inserted into the socket, and formed on the outer peripheral surface of the spigot and disposed on the back side of the lock ring to be locked to the lock ring A detachable joint comprising a stopper stepped portion and a rubber ring contact portion sealed by the rubber ring, wherein the rubber ring contact portion is made thicker over the entire length of the expansion and contraction margin. .