JPH09303665A - Electric fusion splicing joint - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an electric fusion splicing joint that can surely prevent gas leakage and secure a gas flow rate to a branch pipe. SOLUTION: A cutter 5 provided on a convex surface of a saddle portion 1 is housed in the pipe, the cutter 5 is movable along a pipe axis, a branch pipe 3 is provided on an outer surface thereof, and an O-ring 6 is provided on a head thereof.
Cylindrical tube 2 provided with a mechanism 4 capable of gas sealing via
In the electric fusion branching joint having the stopper 7, a stopper 7 is provided near the head of the cylindrical tube 2 so that the head of the cutter 5 does not exceed the head of the cylindrical tube 2 when the cutter 5 moves.
An electric fusion branch joint, characterized in that

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric fusion splicing joint made of a thermoplastic resin, and more particularly to an electric fusion splicing joint used when a branch pipe is taken out from a gas-permeable resin pipe.

[0002]

2. Description of the Related Art Electrofusion joints made of thermoplastic resin are
The heating wire embedded in the inner surface of the joint is energized from the connector pin, and the outer surface of the resin gas pipe or the like to be connected to the inner surface of the joint is heated and fused for connection. In recent years, with the widespread use of resin pipes that are lightweight, have excellent corrosion resistance, and are flexible and have the characteristics of being strong against earthquakes, their demand is rapidly expanding.

There are various types of this electric fusion splicing joint, and there is an electric fusion splicing joint called a service tee for taking out a branch pipe without stopping gas from a resin pipe through which gas flows.

FIG. 3 shows an electric fusion branch joint which is generally used at present. In the figure, 1 is a saddle part, 2 is a cylindrical pipe, 3 is a branch pipe, 4 is a cap, 5 is a cutter, and 6 is O.
Represents a ring. In the following figures, the same numbers represent the same items.

On the convex surface of the saddle part 1, a cylindrical cutter 5 usually made of metal is housed in the pipe, a branch pipe 3 is provided on the outer surface thereof, and a gas is supplied to the head through an O-ring. It has a structure in which a cylindrical tube 2 provided with a sealable cap 4 is provided.

The saddle part 1, the cylindrical pipe 2 and the branch pipe 3 are integrally molded by injection molding, and the cutter 5 is housed in the cylindrical pipe 2 after the injection molding. A female screw is formed on the inner surface of the cylindrical tube 2 and a male screw is formed on the outer surface of the cutter 5, so that the cutter 5 can move in the cylindrical tube 2 along the tube axis by a screw mechanism. Further, the cap 4 is often made of the same resin as the saddle portion 1 and the like.

This electric fusion splicing branch joint is used as follows. First, an existing resin pipe (hereinafter,
An electric fusion branch joint is fused to a main pipe), and a pipe through which a gas is allowed to pass is branched into the branch pipe 3 of the electric fusion branch joint.
Then, the cutter 5 is attached to the cylindrical tube 2 using an auxiliary tool for punching.
The inside is moved along the tube axis to perforate the side surface of the original tube. After that, when the cutter 5 is pulled up to the vicinity of the head of the cylindrical pipe 2, the gas is circulated from the main pipe to the branch pipe 3. At this time, although the outer surface of the cutter 5 and the inner surface of the cylindrical tube 2 are screw-fitted, a small amount of gas leakage occurs. Therefore, the gas leakage is completely prevented by gas-sealing the head of the cylindrical tube 2 with the cap 4 through the O-ring 6.

After the construction, the cutter 5 is left in the tube of the cylindrical tube 2, and the resin piece obtained by punching the original tube is also left in the tube of the cylindrical cutter 5.

[0009]

However, since the movement of the cutter is performed manually, when the cutter is pulled up to the vicinity of the head of the cylindrical pipe after the main pipe is drilled, the head of the cutter is moved to the head of the cylindrical pipe. It may be pulled up to a position beyond the part. In particular, it tends to occur when the tightening of the drilling auxiliary tool is insufficient, or when the cutter co-rotates when the drilling auxiliary tool is rotated and removed. Therefore, even if the cap is tightened, the O-ring and the head of the cylindrical tube do not come into close contact with each other to form a gap, and it is impossible to completely prevent gas leakage.

On the other hand, if the cutter is not pulled up sufficiently, the cutter may block a part of the branch pipe so that a predetermined gas flow rate cannot be secured.

The present invention has been made to solve the above problems, and an object thereof is to provide an electric fusion splicing joint which can surely prevent gas leakage and secure a gas flow rate to a branch pipe. And

[0012]

Means for Solving the Problems The above-mentioned problems are provided on the convex surface of the saddle portion, a cutter movable along the pipe axis is housed in the pipe, and a branch pipe is provided on the outer surface thereof.
In an electric fusion branching joint having a cylindrical tube whose head is provided with a mechanism capable of gas sealing via an O-ring, the head of the cutter does not exceed the head of the cylindrical tube when the cutter moves. The electric fusion branching joint is characterized in that a stopper is provided near the head of the cylindrical tube.

Since the stopper is provided in the vicinity of the head of the cylindrical tube, the movement of the head of the cutter is restricted by the stopper when the cutter is moved, and the head of the cylindrical tube is not exceeded. Therefore, there is no gap between the O-ring and the head of the cylindrical tube, and the gas can be reliably sealed through the O-ring.

If the cutter is pulled up until it hits the stopper, the gas flow to the branch pipe is not obstructed by the cutter, so that the gas flow rate to the branch pipe can be reliably ensured.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows one embodiment in the vicinity of the cylindrical pipe head of the electric fusion branch joint of the present invention. Figure (a) is a vertical sectional view, Figure (b) is a sectional view taken along the line AA 'of Figure (a), and 7 represents a stopper.

A ring-shaped stopper 7 having an inner diameter smaller than the outer diameter of the head portion of the cutter 5 is provided on the inner surface near the head portion of the cylindrical tube 2, so that the head portion of the cutter 5 is the same as that of the cylindrical tube 2. It does not project beyond the head. Therefore, the head of the cylindrical tube 2 can be reliably gas-sealed by the cap 4 via the O-ring 6.

Further, if the cutter 5 is pulled up until it hits the stopper 7, the flow of gas to the branch pipe 3 is not obstructed by the cutter 5, so that the gas flow rate to the branch pipe 3 can be reliably ensured.

FIG. 2 shows another embodiment of the stopper shape provided in the electric fusion branching joint of the present invention.

FIG. 1 (c) shows a stopper 7 in which the ring-shaped stopper of FIG. 1 is divided into two parts, and FIG. 2 (d) shows two rectangular plates whose intervals are smaller than the outer diameter of the head of the cutter 5. It is the stopper 7 arranged at.

The stopper 7 may be made of any material as long as it has a strength to withstand the force applied when the cutter 5 is manually moved by the screw mechanism.

The setting position of the stopper 7 is not particularly limited as long as it is near the head of the cylindrical pipe 2, but the cutter 5 is placed at a position where the flow of gas from the main pipe to the branch pipe 3 is blocked by the cutter 5. It is necessary to avoid locations that come.

[0022]

Since the present invention is constructed as described above, it is possible to provide an electric fusion splicing joint which can surely prevent gas leakage and secure a gas flow rate to a branch pipe.

[Brief description of drawings]

FIG. 1 is a diagram showing one embodiment of the vicinity of a cylindrical pipe head portion of an electric fusion branching joint according to the present invention.

FIG. 2 is a view showing another embodiment of the stopper shape provided in the electric fusion branch joint of the present invention.

FIG. 3 is a view showing a conventional general electric fusion splicing joint.

[Explanation of symbols]

 1 Saddle part 2 Cylindrical pipe 3 Branch pipe 4 Cap 5 Cutter 6 O-ring 7 Stopper

Front Page Continuation (72) Inventor Naoshi Murata 1-2 1-2 Marunouchi, Chiyoda-ku, Tokyo Nihon Steel Pipe Co., Ltd.

Claims (1)

[Claims] 1. A cutter provided on a convex surface of a saddle part, in which a cutter movable along a pipe axis is housed, a branch pipe is provided on an outer surface of the cutter, and a gas is introduced through an O-ring on its head. In an electric fusion branching joint having a cylindrical tube provided with a sealable mechanism, a stopper near the head of the cylindrical tube so that the head of the cutter does not exceed the head of the cylindrical tube when the cutter moves. An electric fusion branch joint, characterized in that