JPH05248586A - Mechanical joint with built-in heating wire - Google Patents

Abstract

PURPOSE:To provide a mechanical joint with a built-in heating wire by which the piping work can simply and surely be achieved. CONSTITUTION:A mechanical joint consists of a joint body 1 having a female screw 11 on the inner surface of the end part, a pressing nut 2 having a male screw 21 which is screwed into the female screw 11, and a socket 3 made of synthetic resin which is mounted within the joint body 1. A heating wire 32 is embedded in the inner circumferential surface of this socket 3 at the specified interval. This arrangement allows the inner circumferential surface of the socket and the outer circumferential surface of the end part of the pipe of synthetic resin to be fusion-joined, and the piping work to be achieved in a short time and in a simple and reliable manner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical joint having a built-in heating wire, which enables easy and reliable piping work.

[0002]

2. Description of the Related Art Conventionally, mechanical joints have been used in various pipe construction fields. This mechanical joint has a structure in which the female screw of the joint body is screwed into the male screw of the retainer nut to press the socket loaded in the joint body with the retainer nut, and a synthetic resin pipe is connected using this mechanical joint. When doing so, the piping was constructed in the following procedure. That is, a holding nut and a socket are set at the ends of the respective synthetic resin pipes that have been piped from both sides, then inserted into both ends of the joint body, and the socket is pressed by the holding nut screwed into the joint body.

[0003]

However, in the conventional mechanical joint, since the end portion of the synthetic resin pipe and the socket are connected by using an adhesive, it takes a long time until the both are completely adhesively joined. Therefore, there is a problem that it takes time to construct the pipe.

The present invention has been made to solve the above problems and provides a mechanical joint having a built-in heating wire, which enables simple and reliable piping work in a short time.

[0005]

According to the present invention, there is provided a joint main body having an internal thread on an inner surface of an end, a press nut having an external thread to be screwed with the internal thread, and a synthetic resin socket having a flange on an outer circumference of one end. In a mechanical joint configured to press the flange of the socket loaded in the joint body with a holding nut screwed with the joint body, a heating wire is embedded at a predetermined interval on the inner peripheral surface of the socket. It is a feature.

[0006]

Since the heating wire is embedded in the inner peripheral surface of the synthetic resin socket, when the socket is externally fitted to the end of the synthetic resin tube and the heating wire is energized to generate heat, the heating wire is combined with the inner peripheral surface of the socket. The outer peripheral surface of the end portion of the resin pipe is melted and fusion bonded.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a half sectional front view of a mechanical joint showing an embodiment of the present invention, FIG. 2 is a vertical sectional view of a mechanical joint showing another embodiment of the present invention, and FIG. 3 is a further embodiment of the present invention. It is a longitudinal cross-sectional view of the mechanical joint shown.

First, the mechanical joint A1 shown in FIG. 1 will be described. This mechanical joint A1 includes a joint body 1, a press nut 2, a socket 3 and a seal packing 4.
It consists of The outer surface of the joint body 1 is formed in a polygonal shape such as a hexagon or an octagon, and female threads 11 are provided on the inner surfaces of both ends thereof. A stopper 12 is provided in the center of the inner surface of the joint body 1, and annular grooves 120 for accommodating the seal packing 4 and one end of the socket 3 are provided on both sides of the stopper 12.

The press nut 2 is provided with a male screw 21 to be screwed into the female screw 11 of the joint body 1, and the outer surface of a flange portion 22 provided on the outer periphery of one end portion thereof has a hexagonal, octagonal or other polygonal shape. Has been formed. Joint body 1 of this embodiment
The press nut 2 is made of metal such as cast iron, synthetic resin such as vinyl chloride resin, or other appropriate material. On the other hand, the socket 3 is a cylindrical body made of a synthetic resin such as polyethylene, polypropylene or polybutene having a flange 31 provided on the outer periphery of one end thereof, and a heating wire 32 is embedded spirally at a predetermined interval on the inner peripheral surface thereof. Has been done.

When connecting the synthetic resin pipe 5 to the mechanical joint A1, first, as shown on the right side of FIG. 1, set the holding nut 2 and the socket 3 at the end of the synthetic resin pipe 5 and install them on both sides of the stopper 12. The seal packing 4 is attached to the annular groove 120. Therefore, as shown on the left side of FIG. 1, the end portion of the synthetic resin pipe 5 is fitted into the joint body 1, and the female screw 11 of the joint body 1 is screwed into the male screw 21 of the holding nut 2. Then, the flange 31 of the socket 3 is pressed by the press nut 2, and the end surface of the flange 31 comes into pressure contact with the stopper 12 via the seal packing 4.

During this connecting operation, if a predetermined space is provided between the ends of the respective synthetic resin pipes 5 that have been piped from both sides, when the flange 31 of the socket 3 is pressed by the holding nut 2, the socket 3 3 advances from the end of the synthetic resin pipe 5 and comes into pressure contact with the seal packing 4. On the other hand, the synthetic resin pipes 5 are fitted into both ends of the joint body 1 without sagging. Therefore, when an electric current is passed through the heating wire 32 buried in the inner peripheral surface of the socket 3 for a predetermined time to generate heat, the inner peripheral surface of the socket 3 and the outer peripheral surface of the end portion of the synthetic resin pipe 5 are melted at the same time and fusion-bonded. To do.

When the synthetic resin pipes 5 are sequentially piped from one side to the other side, the sockets 3 may be fusion-bonded to the ends of the synthetic resin pipes 5 in advance and then fitted into the joint body 1. .. That is, the socket 3 is externally inserted to the end of the synthetic resin pipe 5,
The heating wire 32 embedded in the inner peripheral surface of the socket 3 is energized to fuse and bond the inner peripheral surface of the socket 3 and the outer peripheral surface of the end portion of the synthetic resin pipe 5. Therefore, the end of the synthetic resin pipe 5 is connected to the joint body 1
, And the flange 31 of the socket 3 is pressed by the holding nut 2 screwed to the joint body 1 to connect.

The mechanical joint A2 of another embodiment shown in FIG. 2 does not require the seal packing 4 of the above embodiment. The joint body 1 is made of a synthetic resin such as polyethylene, polypropylene or polybutene, and a stopper 12 is provided at the center of the inner surface of the joint body 1, and heating wires 13 are embedded at predetermined intervals on both side surfaces of the stopper 12. .. Both ends of the heating wire 13 are connected to pins 15 of a connector 14 provided on the outer surface of the joint body 1.

When the synthetic resin pipe 5 is connected to the mechanical joint A2 of this embodiment, as shown on the right side of FIG. 2, the press nut 2 and the socket 3 are set at the end of the synthetic resin pipe 5 and then the joint body. Insert into 1. After the ends of the synthetic resin pipe 5 are fitted and inserted into both ends of the joint body 1 in this manner, the heating wire 32 and the stopper 1 embedded in the inner peripheral surface of the socket 3
When the heating wire 13 embedded in the side surface of 2 is energized to generate heat, the inner peripheral surface of the socket 3 and the outer peripheral surface of the end portion of the synthetic resin pipe 5 are melted and fusion-bonded to each other, and the end surface of the socket 3 and the stopper are joined together. The side surface of 12 is melted and fusion-bonded.

The mechanical joint A3 shown in FIG. 3 is a stopper 1 in the embodiment shown in FIG.
Instead of 2, the heating wire 13 wound in a spiral shape is arranged. The outer surface of the heating wire 13 is covered with polyethylene or the like, and both ends of the heating wire 13 which are spirally wound so as not to contact each other are connected to the pins 15 of the connector 14 provided on the outer surface of the joint body 1. ing. The synthetic resin pipe 5 is connected to the mechanical joint A3 of this embodiment in the same manner as the embodiment shown in FIG.

[0016]

As described in detail above, in the mechanical joint of the present invention, the heating wire is embedded in the inner peripheral surface of the socket. Therefore, the socket is externally fitted to the end of the synthetic fat tube and then the heating wire is energized. The socket can be fusion-bonded to the end portion of the synthetic resin pipe only by generating heat. Therefore, compared with the conventional joint in which the socket is adhesively bonded to the end of the synthetic resin pipe using the adhesive, the mechanical joint of the present invention makes the pipe construction on site in a short time, simple and reliable. I can do it.

[Brief description of drawings]

FIG. 1 is a front view, in half section, of a mechanical joint showing an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a mechanical joint showing another embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view of a mechanical joint showing still another embodiment of the present invention.

[Explanation of symbols]

 A1 Mechanical joint A2 Mechanical joint A3 Mechanical joint 1 Joint body 2 Presser nut 3 Socket

Claims (1)

[Claims] 1. A joint body (1) having an internal thread (11) on an inner surface of an end, a holding nut (2) having an external thread (21) screwed to the internal thread (11), and a collar (1) on the outer periphery of one end. And a flange (31) of the socket (3) loaded in the joint body (1), and a screw nut (2) screwed to the joint body (1). A mechanical joint having a built-in heating wire, characterized in that the heating wire (32) is embedded at a predetermined interval on the inner peripheral surface of the socket (3).