JP2599211B2 - Electric fusion joint - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electro-fusion joint, and more particularly to an electro-fusion joint used for, for example, piping for fluid transport.

(Prior art)

Conventional electric fusion joint (hereinafter simply referred to as “joint”) 1
As shown in FIG. 6, includes a substantially hollow cylindrical main body 2 made of a synthetic resin such as polyethylene or polybutene. Both ends of the heating wire 3 embedded in the main body 2 are protruded from the main body 2 to be energized. The terminal 4 is formed.

[Problems to be solved by the invention]

To perform fusion bonding using such a conventional joint 1,
First, a pipe 6 to be connected to the socket 5 of the joint 1 is inserted,
The joint 1 and the pipe 6 are fixed by a clamp jig (not shown). Next, an electric wire of a power supply device (not shown) is connected to the energizing terminal 4 to energize the heating wire 3. After energizing for a predetermined time, the fusion surface is cooled in that state, that is, with the joint 1 and the pipe 6 fixed with a clamp jig, and the clamp jig is removed after the fusion surface is solidified. I was It took several tens of seconds to 5 minutes to energize, and 5 to 20 minutes to cool and solidify (depending on the size of the joint 1 or the pipe 6).

In such fusion bonding, in order to prevent the pipe 6 from coming off or incomplete fusion, the clamp jig was removed after the fusion surface was completely solidified. In some cases, the connection quality may not be guaranteed, and the quality of the connection cannot be guaranteed.

Further, when joining a plurality of locations, the respective welding cylinder locations are fixed first with a plurality of clamp jigs, and the heating wire 3 of each joint 1 is sequentially and continuously energized. By doing so, it is not necessary to wait for the time for the fusion surface to solidify (about 5 to 20 minutes), and the working efficiency can be improved. However, since the clamp jig is expensive and bulky, a large number of clamp jigs are required. Preparing on site was indeed impossible. Therefore, work efficiency was not so good after all.

Therefore, a main object of the present invention is to provide an electric fusion joint that can prevent accidents such as water leakage and can improve work efficiency.

[Means for solving the problem]

The present invention provides an electrofusion joint including a joint body having a socket and a heating element provided on an inner surface of the socket, wherein the joint body extends in an axial direction of the joint body from an opening-side end of the socket. An electrofusion joint comprising a plurality of fastening pieces integrally formed and displaced inward by a fastening member.

[Action]

The pipe is inserted into the socket of the joint, and the fastening piece is fastened using the fastening member. Then, the inner surface of the fastening piece is pressed against the outer surface of the pipe, and the fastening piece, that is, the joint and the pipe are fixed. An inexpensive and simple (not bulky) fastening member is used, and the once installed fastening member is left as it is without being removed even after the completion of fusion.

〔The invention's effect〕

According to the present invention, since the fastening member is left as it is without being detached even after the completion of the fusion, there is no fear that the fixing between the joint and the pipe is released during the cooling, and therefore, there is no water leakage. And other accidents can be prevented.

Moreover, since a cheap and less bulky fastening member is used, a large number of fastening members can be prepared on site. Therefore, the working efficiency can be improved by a method in which a plurality of fusion spots are fixed first, and the current is sequentially and continuously supplied without waiting for the fusion surface to solidify.

The above and 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.

〔Example〕

Referring to FIGS. 1A and 1B, the joint 10 of this embodiment
The main body 12 includes a substantially hollow cylindrical main body 12 made of a synthetic resin such as polyethylene or polybutene, and a receiving port 16 for receiving a pipe 14 described later is formed at both ends of the main body 12. A heating wire 18 for heating is located near the inner surface of the receiving port 16.
Are embedded, and energizing terminals 20 are formed at both ends of the heating wire 18 so as to protrude from the main body 12. The current-carrying terminal 20 is covered with a covered wire 22.

Then, a fastening portion 24 is formed extending from the opening-side end of the receiving port 16 in the axial direction of the main body 12. The fastening portion 24 includes a plurality (three in this embodiment) of fastening pieces separated by a slit 26.
28, each fastening piece 28 extends in the axial direction of the
It is formed integrally with 12. The thickness of each fastening piece 28 is set slightly smaller than the thickness of the main body 12.

Referring to FIG. 2, at the time of joining, first, a pipe 14 made of a synthetic resin such as polyethylene or polybutene is inserted into the left and right receiving ports 16 of the joint 10, and then, a fastening member 30 is fastened using a fastening member 30. Tighten 24. Then, the inner surface of each fastening piece 28 is pressed against the outer surface of the pipe 14, thereby
And the pipe 14 are temporarily fixed. Then, an electric wire of a power supply device (not shown) is connected to the energizing terminal 20 to energize the heating wire 18.

In addition, as the fastening member 30, an inexpensive and simple (not bulky) material such as an insulation tie (trade name: Tyton Co., Ltd.) shown in FIG. 2 or a hose clip (not shown) is used. Installed fastening member 30
Is left without being removed.

After energization, the fusion bonding is completed when the fusion surface is cooled and solidified, but the fastening member 30 is left as it is after the completion of the bonding. The operation is completed when the power supply to is completed.

According to this embodiment, since the joint 10 and the pipe 14 can be fixed at the time of fusion, it is possible to prevent accidents such as water leakage due to the pipe 14 coming off or incomplete fusion.

Further, since the fastening member 30 is inexpensive and not bulky, it is possible to bring it to the site in large numbers. Thereby, work efficiency can be improved.

The present invention can be applied to a piping member such as a cheese, an elbow, a header or a one-sided joint other than the socket as in the above-described embodiment. For example, when applied to a one-sided joint, as shown in FIG. The fastening portion 24 is formed at the bottom.

Further, the size or the number of the fastening pieces 28 may be appropriately changed, for example, as shown in FIGS. 4A and 4B, and the inner surface of the fastening pieces 28 may be formed as shown in FIG. In addition, irregularities 32 for more reliably preventing the pipe 14 from coming off may be formed.

A groove 34 (FIG. 5) for mounting the fastening member 30 may be formed in the outer circumferential direction of each fastening piece 28. When the fastening member 30 is mounted in the groove 34, the fastening member
30 can be easily positioned and the tightening member
30 can be prevented from falling out.

Further, as the heating means, a hollow cylindrical plate (not shown) or any other heating element may be used instead of the heating wire 18.

[Brief description of the drawings]

1A and 1B are illustrative views showing one embodiment of the present invention. FIG. 1A is a front half sectional view, and FIG. 1B is a right side view. FIG. 2 is an illustrative view showing a state at the time of joining. FIG. 3 is a half sectional view showing another embodiment of the present invention. 4A and 4B are illustrative views showing a modification of the fastening portion, FIG. 4A is a partially omitted front view, and FIG. 4B is a right side view. FIG. 5 is an illustrative view showing another modification of the fastening portion. FIG. 6 is a sectional view showing the prior art. In the figure, 10 is an electrofusion joint, 12 is a main body, 14 is a pipe, 16 is a receiving port, 18 is a heating wire, 20 is an energizing terminal, 24 is a fastening portion, 26 is a slit, 28 is a fastening piece, 30 Indicates a fastening member.

Claims (1)

(57) [Claims] 1. An electrofusion joint including a joint body having a receiving port and a heating element provided on an inner surface of the receiving port, wherein the joint extends from an opening-side end of the receiving port in an axial direction of the joint body. And a plurality of fastening pieces formed integrally with the joint body and displaced inward by a fastening member.