JPH0842774A - Electrically fusion-welded joint - Google Patents

Abstract

PURPOSE:To realize an electrically fusion-welded joint in which both end connections are not used as sockets by using one end part of the joint as a spigot and the other end part as a socket, and by providing a terminal pin connected to an electric heat generating element on the side of the spigot and a terminal pin connected to the electric heat generating element on the side of the. socket on the outer peripheral surface on the side of the socket. CONSTITUTION:A spigot 3 of a pipe joint 1 is inserted into the inside of a large- diameter pipe 4. In this case, since a terminal pin 35 is not on the outer peripheral surface of the spigot 3, the spigot 3 can be inserted into the pipe 4 without obstruction. When the terminal pin 35 is connected to a power source to be electrified a resistance heating wire 31 generates heat to melt the outer peripheral surface of the spigot 3 and to fusion-weld the outer peripheral surface to the inner peripheral surface of the pipe 4. Then, when the tip of a small-diameter pipe 5 is inserted into a socket 2 of the pipe joint 1, and a terminal pin 25 is connected to the power source to be energized, a resistance heating wire 31 generates heat to melt the inner peripheral surface of the socket 2 and to fusion-weld the inner peripheral surface of the socket to the outer peripheral surface of the pipe 5. Since the end connection of the joint at which the large-diameter pipe 4 is to be connected, is a socket, the joint itself becomes compact.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electrofusion joint.

[0002]

2. Description of the Related Art A conventional electric fusion joint is disclosed in Japanese Patent Laid-Open No. 5-87.
As described in JP-A-286 and JP-A-6-28488, both ends of a thermoplastic resin cylinder are used as receiving ports, and electric heating elements are embedded in the inner peripheral surface of the receiving ports. Terminal pins communicating with the electric heating element are provided on the outer peripheral surface of the. Then, this electric fusion-bonding joint inserts the ends of the thermoplastic resin tube into the receiving ports of both ends, connects the terminal pins to the power source,
Energize the electric heating element. Then, the inner peripheral surface of the receiving port is melted by the heat generated by the electric heating element, and the electric fusion joint made of the thermoplastic resin and the thermoplastic resin pipe are fused and connected. Since this electric fusion joint can be firmly connected, it is often used when connecting a gas pipe, a vacuum sewer pipe, a water pipe, and the like. In particular, it is often used for connecting thermoplastic resin pipes such as polyethylene pipes that are difficult to bond with an adhesive.

[0003]

However, since both ends of the conventional electric fusion splicing joint are used as receiving ports, for example,
There is a problem that it cannot be used when connecting a pipe that is used as a receiving port, such as an inlet of a drainage basin. Further, in the case of a pipe joint such as a reducer in which one of the connection ports has a large diameter and the other connection port has a small diameter, if both connection ports are used as the receiving ports, the larger receiving port becomes extremely large. There is a problem that it becomes large and inconvenient to handle, and that manufacturing costs, packing costs, transportation costs, etc. become expensive. Therefore,
It is an object of the present invention to provide a pipe joint made of a thermoplastic resin tubular body, in which both connection ports are not receiving ports.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, in which one end of a thermoplastic resin cylinder is used as an insertion port and the other end is used as a receiving port. In the electrical fusion splicing joint, an electric heating element is embedded in the outer peripheral surface of the insertion opening, an electric heating element is embedded in the inner peripheral surface of the receiving opening, and a terminal pin leading to the electric heating element on the insertion opening side, A terminal pin communicating with the electric heating element on the receiving side is provided on the outer peripheral surface on the receiving side.

[0005]

In order to connect the receptacle of the electric fusion joint of the present invention to the pipe, the end portion of the pipe body is inserted into the receptacle, and the terminal pin is connected to the electric heating element on the receptacle side as in the conventional case. Is connected to the power supply and energized. Then, the electric heating element embedded in the inner peripheral surface of the receiving port generates heat, the inner peripheral surface of the receiving port is melted, and the inner peripheral surface of the receiving port and the outer peripheral surface of the pipe can be fused and connected. To connect the insertion port of the electric fusion joint to the tube, the insertion port is inserted into the tube. At this time, since the terminal pin communicating with the electric heating element on the insertion side is on the outer peripheral surface on the reception side, there is no problem in inserting the insertion port into the tube. In this way, after the insertion port is inserted into the tube, the terminal pin leading to the electric heating element on the insertion port side is connected to the power source and energized. Then, the electric heating element provided on the outer peripheral surface of the insertion opening generates heat to melt the outer peripheral surface of the insertion opening, and the outer peripheral surface of the insertion opening and the inner peripheral surface of the pipe are fused and connected to each other.

[0006]

1 and 2 show one embodiment of the present invention. FIG. 1 is an explanatory view showing a partially cutaway state of an electric fusion joint comprising a reducer, and FIG. 2 is an electric diagram of FIG. It is explanatory drawing which shows the state which has connected the pipe using a fusion splicing.
FIGS. 3 to 4 show another embodiment of the present invention. FIG. 3 is an explanatory view showing a partially cutaway state of the electric fusion joint, and FIG. 4 uses the electric fusion joint of FIG. It is explanatory drawing which shows the state which has connected the pipe.

In FIGS. 1 and 2, reference numeral 1 denotes an electric fusion joint made of a reducer made of polyethylene. One end of the electric fusion joint 1 is a receiving port 2 and the other end is an inserting port 3. Has been done. A resistance heating wire 21 is embedded as an electric heating element on the inner peripheral surface of the receiving port 2. 25
Is a terminal pin provided on the outer peripheral surface of the receiving port 2, and the terminal pin 25 is connected to the resistance heating wire 21. A resistance heating wire 31 is embedded in the outer peripheral surface of the insertion slot 3. Reference numeral 35 denotes a terminal pin provided on the outer peripheral surface of the receiving port 2 side, and the terminal pin 35 is connected to the resistance heating wire 31. Then, one end of the resistance heating wires 21 and 31 to which the terminal pins 25 and 35 are not connected is continuous. Reference numeral 4 is a polyethylene pipe having a large diameter, and the inner diameter of the pipe 4 is substantially equal to the outer diameter of the insertion port 3. Reference numeral 5 is a polyethylene pipe having a small diameter, and the outer diameter of the pipe 5 is substantially equal to the inner diameter of the receiving port 2.

Next, a method of connecting the pipes 4 and 5 using the pipe joint 1 will be described. The insertion port 3 of the pipe joint 1 is inserted into the large-diameter pipe 4. At this time, since there is no terminal pin 35 on the outer peripheral surface of the insertion port 3, the insertion port 3 can be inserted into the tube 4 without any trouble. After that, when the terminal pin 35 is connected to a power source and energized, the resistance heating wire 31 generates heat, and the outer peripheral surface of the insertion port 3 melts and fuses with the inner peripheral surface of the tube 4. As a result, the pipe joint 1 and the pipe 4 can be firmly connected.

Next, when the tip of the small-diameter pipe 5 is inserted into the receiving port 2 of the pipe joint 1 and the terminal pin 25 is connected to the power source and energized, the resistance heating wire 21 generates heat and the inner periphery of the receiving port 2 is heated. The surface melts and fuses with the outer peripheral surface of the tube 5. As a result, the pipe joint 1 and the pipe 5 can be firmly connected. If both ends of the pipe joint 1 are receiving ports, it is necessary to make the inner diameter of the receiving port for connecting the large-diameter pipe 4 approximately equal to the outer diameter of the large-diameter pipe. Therefore, as shown by the dotted line in FIG. This is a large joint, which is expensive and inconvenient because of high manufacturing costs, packing costs, transportation costs, etc. However, in the present embodiment, since the connection port for connecting the large-diameter pipe 4 is an insertion port, the joint itself Is small and easy to manufacture, store, and transport, and therefore, manufacturing costs, storage costs, and transportation costs are low, which is convenient.

Next, the embodiment shown in FIGS. 3 and 4 will be described. In FIGS. 3 and 4, reference numeral 1a denotes an electric fusion joint made of polyethylene, and one end of the electric fusion joint 1a is a receiving port 2a and the other end is an inserting port 3a. A resistance heating wire 21a is provided on the inner peripheral surface of the receiving port 2a.
Is buried. 25a is a terminal pin provided on the outer peripheral surface of the receiving port 2a, and the terminal pin 25a is connected to the resistance heating wire 21a. Insert 3
A resistance heating wire 31a is embedded in the outer peripheral surface of a. Three
Reference numeral 5a is a terminal pin provided on the outer peripheral surface on the side of the receiving port 2a, and the terminal pin 35a is connected to the resistance heating wire 31a. Then, one end of the resistance heating wires 21a and 31a to which the terminal pins 25a and 35a are not connected is continuous.

Reference numeral 6 denotes a polypropylene resin drainage basin.
Reference numeral 61 is a pipe formed of an inlet of the drainage basin 6, and the pipe 61 formed of the inlet is a receiving port. 62 is a drainage box 6
The pipe consisting of the outlet of the
Is an outlet. Reference numeral 7 is a pipe connected to the pipe 61 formed of an inflow port.

Next, a method of connecting the pipe 61 and the pipe 7 using the pipe joint 1a will be described. The insertion port 3a of the pipe joint 1a is inserted into the receiving port of the pipe 61. At this time, since there is no terminal pin 35a on the outer peripheral surface of the insertion port 3a, there is no problem when the insertion port 3a is inserted into the tube 61. After that, when the terminal pin 35a is connected to a power source and energized, the resistance heating wire 31a generates heat and the outer peripheral surface of the insertion port 3a is melted and fused to the inner peripheral surface of the pipe 61. As a result, the pipe joint 1a and the pipe 61 can be firmly connected.

Next, the tip of the pipe 7 is connected to the receiving port 2 of the pipe joint 1a.
When it is inserted into a and the terminal pin 25a is connected to a power source and energized, the resistance heating wire 21a generates heat and the inner peripheral surface of the receiving port 2a is melted and fused with the outer peripheral surface of the pipe 7. as a result,
The pipe joint 1a and the pipe 7 can be firmly connected. in this way,
This electric fusion splicing joint 1a can be used also when connecting the pipe 7 to the pipe 61 which is a receiving port like the inflow port of the drainage box 6.

[0014]

As can be seen from the above description, the electric fusion splicing joint of the present invention, like the conventional electric fusion splicing joint, fuses the tubular body and the joint by energizing the electric heating element to make the joint strong. Can be connected to. Further, the conventional electric fusion splicing joint has only the receiving port, but the electric fusion splicing joint of the present invention has the one end portion as the insertion opening and the other end portion as the receiving opening, so that the inlet of the drainage box is formed. It can be used by inserting the insertion port into the tube body which has been used as the receiving port and connecting it. Further, if a joint having a large-diameter side as a reducer, such as a reducer, becomes an extremely large joint, it is not only inconvenient but also the manufacturing cost, storage cost, and transportation cost are high. Since one connection port of the joint is used as an insertion port, the joint can be made small and the cost is low. Since the electric fusion splicing joint of the present invention is provided on the outer peripheral surface on the receiving side of the terminal pin that communicates with the electric heating element embedded in the outer peripheral surface of the insertion opening, when the insertion opening is inserted into the tubular body, this terminal pin is It does not get in the way.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention and is an explanatory view showing a partially cutaway state of an electric fusion joint comprising a reducer.

FIG. 2 is an explanatory view showing a state where pipes are connected using the electric fusion joint of FIG.

FIG. 3 shows another embodiment of the present invention and is an explanatory view showing a partially cutaway state of the electric fusion joint.

FIG. 4 is an explanatory diagram showing a state where pipes are connected using the electric fusion joint of FIG.

[Explanation of symbols]

 1, 1a Electric fusion joint (reducer) 2, 2a Receptacle 21, 21a Electric heating element 25, 25a Terminal pin 3, 3a Insertion mouth 31, 31a Resistance heating wire 35, 35a Terminal pin

Claims (1)

[Claims] 1. An electric fusion joint in which one end of a thermoplastic resin cylinder is used as an insertion port and the other end is used as a receiving port, and an electric heating element is provided on an outer peripheral surface of the insertion port. An electric heating element is embedded in the inner peripheral surface of the receiving port, and a terminal pin communicating with the electric heating element on the insertion side and a terminal pin communicating with the electric heating element on the receiving side are provided on the outer peripheral surface on the receiving side. An electric fusion joint characterized by the following.