JPS63285396A - Electric fusion type synthetic-resin pipe joint - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a synthetic resin pipe joint for connecting synthetic resin pipes, and particularly to a socket-type electrical joint for connecting synthetic resin pipes in a straight direction. This invention relates to fusion-bonded synthetic resin pipe joints.

[Conventional technology] Conventional socket-type electric fusion synthetic resin pipe fittings have
For example, there is a pipe joint as shown in FIGS. 5 and 6, which is disclosed in Japanese Patent Application Laid-open No. 59-13180. FIG. 5 is a front view of a preform 5 made of synthetic resin with a resistance conductor 24 wound around it, and FIG. Outer covering 13 of resin material
FIG. 2 is a longitudinal cross-sectional view of a socket-type electrically fusion type synthetic resin side pipe joint in which is formed. 5 and 6, in this conventional pipe joint, one end of a resistance conductor 24 is fixed to a tubular preform 5 made of synthetic resin, and the resistance conductor 24 is heated to form a spiral into the preform 5. The resistance conductor 24 is wound, and the other end of the resistance conductor 24 is fixed to a preform, and the outer peripheral surface of the preform 5 around which the resistance conductor 24 is wound is covered with a synthetic resin material by injection molding or the like to form a jacket 13. This is a socket-type electric fusion type synthetic resin pipe joint that was manufactured. In FIG. 6, both ends of the resistance conductor 24 are fixed to support columns 25, and the middle portion thereof is surrounded by a synthetic resin preform 5 and a synthetic resin jacket 13.

Further, each metal cap 27 fitted over each support column 25 is electrically connected to the resistance conductor wire 24.

Connection of synthetic resin pipes using this pipe joint is performed using a stopper 31 that protrudes from the inner peripheral surface of the synthetic resin pipe as shown in Fig. 6.
(stopping device) from both ends of the pipe joint, and passing a current through the metal cap 27 to generate heat in the resistance conductor 24.
This is done by melting and attaching the circumferential surface of the pipe joint and the outer circumferential surface of the synthetic resin pipe.

[Problems to be Solved by the Invention] In the conventional electric fusion type synthetic resin pipe joint described above, it is necessary to fix a resistance conductor, that is, a heating wire to a preform, and further to wind the wire in a spiral shape. SUMMARY OF THE INVENTION An object of the present invention is to provide an electrically fused synthetic resin pipe joint that does not require a heating wire to be fixed and wound around a preform.

[Means for Solving the Problems] The present invention comprises a substantially cylindrical pipe joint inner cylinder made of synthetic resin, a conductive metal printed on the outer peripheral surface of the pipe joint inner cylinder, and a conductive metal printed on the outer peripheral surface of the pipe joint inner cylinder. 2 embedded in both ends of the conductive metal on the outer peripheral surface
An electric fusion type, characterized in that it consists of a main connector bin, and a synthetic resin pipe fitting outer cylinder that is molded to cover the outer circumferential surface of the pipe fitting inner cylinder in which the conductive metal is printed and the connector bin is embedded. This is a synthetic resin pipe fitting. Since the electric fusion type synthetic resin pipe joint according to the present invention prints a conductive metal instead of winding the heating wire in a spiral shape, it is necessary to fix one end of the heating wire to a preform or the like and wind it in a spiral shape. There isn't.

[Embodiment] An embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. 1 is a longitudinal cross-sectional view of a socket-type electric fusion type synthetic resin pipe fitting 1 according to this embodiment. Figures 1 and 2
In the figure, a pipe joint inner cylinder 2 is approximately cylindrical and made of synthetic resin, and metal connector pins 4 are embedded and fixed in both ends thereof. A flange-shaped flange portion is formed in the middle of the connector bin 4, and the lower surface of this flange is in contact with the outer circumferential surface of the pipe joint inner cylinder 2. An upper portion of the flange portion of the connector 4 protrudes from the outer circumferential surface of the pipe joint inner cylinder 2. Further, an annular projection 22 is formed at the center of the inner circumferential surface of the inner cylinder 2 of the pipe joint, and this annular projection 22
This is a part of the stopper described in the prior art section.

A conductive metal is printed on the outer peripheral surface of the pipe joint inner cylinder 2, and a synthetic resin resin is printed on the outer peripheral surface of the pipe joint inner cylinder 2 in which the conductive metal is printed and the connector bin 4 is embedded and fixed. The pipe joint outer cylinder 3 is covered by, for example, injection molding. At this time, the outer peripheral surface of the pipe joint outer cylinder 3 around the connector pin 4 forms a recessed part, and the area around these four parts has a protruding shape than the other outer peripheral surface of the pipe joint outer cylinder 3.

Next, FIGS. 3 and 4 show perspective views of the pipe joint inner cylinder 2 made of synthetic resin. A conductive metal 21 is printed on the inner cylinder 2 of the pipe joint, and the printed pattern is a wire or band-shaped wire wound spirally around the outer circumferential surface of the inner cylinder 2 of the pipe joint, as shown in Fig. 3. The outer peripheral surface near the annular protrusion 22 has a rough spiral winding. There is also a pattern shown in FIG. 4 as another printed pattern.

That is, the outer circumferential surface of the pipe joint inner cylinder 2 is divided into blocks in the axial direction, and within each block, a wavy line or band-like line is wound in the axial direction over the entire outer circumferential surface of each block, and these lines or band-like lines are There is one. The reason why the outer peripheral surface of the pipe joint inner cylinder 2 is divided into two blocks is because of the annular protrusion 2.
This is to coarsen the printing density of the conductive metal 21 on the outer circumferential surface near 2. The pattern printed with conductive metal 21 is 1
Although it is a real line or a belt-like line, there are blind holes at both ends of this pattern for embedding and fixing the connector pin 4. In addition, the connector pin 4 having the flange portion and the printed conductive metal 21 must be electrically connected. From these facts, both ends of the pattern are printed around the blind holes. The connector pin 4 is embedded in the pipe joint inner tube 2 on which the conductive metal 21 is printed. This is done by filling in holes drilled at both ends of the printed pattern. Print this conductive metal 21 and attach the connector bin 4 to 2
A synthetic resin tube joint outer tube 3 is molded onto the embedded tube joint inner tube 2 by injection molding or the like to complete an electric fusion type synthetic resin tube joint.

Next, printing of the conductive metal 21 will be explained. The printing is performed by screen printing, and a pattern is formed by penetrating the conductive metal 21 onto a screen substrate made of nylon cloth or stainless steel cotton cloth. This screen substrate is fixed over the entire or half circumference of the outer circumferential surface of the pipe joint inner cylinder 2 with a very small gap, and the upper surface of this screen substrate is pressed with a pressing plate erected. The contact portion of this press plate with the screen substrate is made of rubber. While pressing this suppression plate against the screen substrate, the screen substrate and the pipe joint inner cylinder 2 are rotated and reciprocated. At this time, a paste-like conductive metal 21. For example, a copper paste or the like is poured and printed on the outer peripheral surface of the inner tube 2 of the pipe joint. In addition, in order to improve the adhesion of printing, the pipe joint inner cylinder 2 may be heated as a pretreatment. The electric fusion type synthetic resin pipe joint of the present embodiment described above does not require wiring for fixing heating wires and winding them in a spiral shape, and has the advantage that printing patterns can be freely selected.

[Effects of the Invention] The electric fusion type synthetic resin pipe joint according to the present invention has the advantage that spiral winding of heating wires is unnecessary.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of an electrofusion type synthetic resin pipe joint showing an embodiment of the present invention, Fig. 2 is an enlarged cross-sectional view of the end of Fig. 1, and Fig. 3 is an embodiment of the present invention. Perspective view of pipe joint inner cylinder, No. 4
The figure is also a perspective view with a different printing pattern. Fig. 5 is a front view of a conventional electric fusion type synthetic resin pipe joint in which a heating wire is wound around a preform, and Fig. 6 is a longitudinal cross-sectional view of a conventional electric fusion type synthetic resin pipe joint. . 1... Electric fusion type synthetic resin pipe joint 2... Pipe joint inner cylinder, 21... Conductive metal 3.
...Pipe joint outer cylinder, 4...Connector bin 5...
・Preform 24...resistance conductor, that is, heating wire Fig. 2 Fig. 5

Claims (2)

[Claims] (1) A substantially cylindrical pipe joint inner cylinder made of synthetic resin, a conductive metal printed on the outer peripheral surface of the pipe joint inner cylinder, and a conductive metal embedded in both ends of the conductive metal on the outer peripheral surface of the pipe joint inner cylinder. The electric fusion device comprises two connector pins embedded in the pipe joint, and a synthetic resin pipe joint outer cylinder that is molded to cover the outer peripheral surface of the pipe joint inner cylinder in which the conductive metal is printed and the connector pins are embedded. Fitted type synthetic resin pipe fitting. (2) The electric fusion type synthetic resin pipe joint according to claim 1, wherein the printing is screen printing.