JP2002144433A - Sleeve tube and connecting structure for piping material using this sleeve tube to joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sleeve tube capable of easily fusion bonding a piping material made of all thermoplastic resin to a joint without raising a manufacturing cost of the joint and a connecting structure of the piping material using the sleeve tube to the joint. SOLUTION: The sleeve tube made of a non-crosslinking thermoplastic resin is engaged at its inlet engaging part within an inlet made of a crosslinking thermoplastic resin of the joint. The sleeve tube is rotated in a state in which one end made of a crosslinking thermoplastic resin is engaged with its piping material engaging part. An inner peripheral surface of the joint is rotatably frictionally fusion bonded to an outer periphery of the inlet engaging part of the sleeve tube and the outer peripheral surface of the engaging part of the piping material is rotatably frictionally fusion-bonded to the inner peripheral surface of the piping material of the sleeve tube by the rotation of the sleeve tube.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sleeve tube and a connection structure between a pipe member and a joint using the sleeve tube.

[0002]

2. Description of the Related Art As a method of joining a thermoplastic resin pipe and a joint, as described in Japanese Patent Application Laid-Open No. 2-186193, a heating wire is embedded in advance near the interface of the joint of the joint at the time of molding. An electric fusion method (a method using an electrofusion joint) in which the heating wire is energized during the joining to melt the thermoplastic resin tube by causing the resin at the interface of the joint to be in a molten state by the heat generated by the heating wire, or Heat the joint port of the joint and the joint end of the piping material using a panel to make it in a molten state, remove the hot platen, and keep the joint end of the pipe material in the joint port while maintaining this molten state. Conventionally, a method of fitting and fusing a pipe material to a joint (a method using a heat fusion joint) has been used.

On the other hand, as described in Japanese Patent Application Laid-Open No. 2-186193, it is difficult to join a crosslinked polyethylene pipe excellent in heat resistance and high-temperature creep properties by fusion. Therefore, in the case of the joint disclosed in JP-A-2-186193, only the joint surface with the pipe material is formed of a non-crosslinked thermoplastic resin, and the other portions are formed of a crosslinked thermoplastic resin.

[0004] However, it is said that, when integrally forming the crosslinked thermoplastic resin portion and the non-crosslinked thermoplastic resin portion by injection molding, the mold becomes complicated, the manufacturing cost of the mold is increased, and the maintainability is poor. There's a problem.

On the other hand, the present applicant has already proposed a rotary friction welding method as a joining method capable of joining crosslinked thermoplastic resins (Japanese Patent Application No. 11-194541). According to this fusion method, since the crosslinked thermoplastic resins can be joined to each other, the molding die for the joint does not become complicated as in the above-described conventional method.

[0006] However, the types of joints vary in shape, such as male screw adapters, female screw adapters, union sockets, elbows, and the like, and each joint can be connected to only one type of pipe material. Therefore, although joints for each diameter are prepared, there is a problem that the cost of the mold is increased. Also, the diameter of the pipe material connected by these joints and the pipe material to be connected may be long or not straight such as a bend pipe or a header pipe. Some materials or joints may not be able to rotate properly and may not be able to perform rotational friction welding.

[0007]

SUMMARY OF THE INVENTION In view of the foregoing, it is an object of the present invention to provide a sleep pipe in which any thermoplastic resin piping material and a joint can be easily fused and joined without increasing the manufacturing cost of the joint. It is another object of the present invention to provide a connection structure between a pipe member and a joint using the sleeve tube.

[0008]

In order to achieve such an object, a sleeve tube according to the first aspect of the present invention (hereinafter referred to as a "sleeve tube of the first aspect") is provided.
One end of a pipe member connected from one end thereof can be externally fitted, and the other end thereof is formed so as to be able to be internally fitted in a socket of a joint, and at least one end of the pipe member is externally fitted. The inner peripheral surface of the fitting portion and the inner peripheral surface of the socket fitting portion to be fitted into the fitting socket are formed of a synthetic resin material that can be fused to the fitting portion outer peripheral surface of the pipe material and the fitting inner circumferential surface of the fitting. Configuration.

A sleeve tube according to the second aspect of the present invention (hereinafter referred to as "sleeve tube of the second aspect").
Was formed from non-crosslinked polyethylene.

According to the third aspect of the present invention, a connection structure between a pipe member and a joint (hereinafter referred to as a “third connection structure”) is a sleeve according to the first or second aspect. The pipe has its socket fitting portion inserted into the fitting socket, and the pipe material fitting portion has the connecting end of the pipe material fitted therein, and the inner peripheral surface of the pipe material fitting portion of the sleeve tube and the pipe material have the same shape. The outer peripheral surface of the connection end portion, the outer peripheral surface of the socket fitting portion of the sleeve tube, and the inner peripheral surface of the socket of the joint were each fused.

According to a fourth aspect of the present invention, there is provided a connection structure between a pipe member and a joint (hereinafter, referred to as a "fourth connection structure"). It is made of non-cross-linked polyethylene, and at least the joint forming part of the joint and the connection end of the pipe material are formed of cross-linked polyethylene, and the sleeve pipe, the pipe material and the joint are fused by a rotational friction welding method. It was configured to be worn.

According to a fifth aspect of the present invention, there is provided a connection structure between a pipe member and a joint (hereinafter referred to as a “fifth connection structure”) according to the third or fourth connection structure. In addition, the receiving port of the joint is formed so that piping materials having a plurality of diameters can be connected.

The fusion method using the sleeve tube according to the present invention comprises:
For example, the inner peripheral surface of the pipe material fitting portion of the sleeve tube and the outer peripheral surface of the connecting portion of the piping material, the outer peripheral surface of the socket fitting portion of the sleeve tube, and the inner peripheral surface of the joint are heated and melted using a hot plate. A heat fusion method for heat-sealing, or fitting the connection part of the pipe material into the pipe material fitting part of the sleeve pipe, and fitting the sleeve fitting with the socket fitting part into the fitting fitting socket. Rotation about the axis, the inner peripheral surface of the pipe material fitting part of the sleeve tube and the outer peripheral surface of the connection part of the piping material,
Rotational friction welding, etc., in which the outer peripheral surface of the socket fitting portion of the sleeve tube and the inner peripheral surface of the joint are fused, can be used. Claim 4 when formed of a thermoplastic resin having poor resistance.
It is preferable to use the rotational friction welding method as in the connection structure of (1).

In the present invention, the pipe material includes not only a pipe but also a joint having a spout.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
This will be described in detail with reference to the drawings. FIG. 1 shows a first embodiment of a sleeve tube according to the present invention.

As shown in FIG. 1, this sleeve tube 1a
Are medium density polyethylene, linear low density polyethylene,
The connection pipe fitting portion 12 is formed of non-crosslinked polyethylene such as low-density polyethylene and can be externally fitted to one end of a pipe material connected from one end, and can be internally fitted into a socket of a joint connected from the other end. And a formed receptacle fitting portion 11.

FIG. 2 shows a sleeve tube according to a second embodiment of the present invention. As shown in FIG. 2, the sleeve tube 1b has a pipe material fitting portion 13 having an inner diameter smaller than that of the pipe material fitting portion 12 such that a pipe material having one size smaller than that of the sleep pipe 1a is fitted. Is the same as the sleeve tube 1a.

These sleeve tubes 1a and 1b are, for example, as shown in FIG. 3 to FIG. 5 in which a female screw socket 2a as a joint and a pipe material 3 made of crosslinked polyethylene having a gel fraction of 65% or more are as follows. To be able to connect.

The female screw socket 2a is provided with a socket 24 having a socket 24 and made of crosslinked polyethylene having a gel fraction of 65% or more, and a female screw cylindrical portion made of insert metal when the socket 21 is formed. 22
And a caulking fitting 23. The socket body 21 has a pipe passage portion whose diameter is reduced stepwise toward the back, and the large diameter portion 25 is formed of a sleeve tube 1.
The small diameter portion 26 has substantially the same diameter as the inner diameter of the sleeve tube 1b. You. On the other hand, the piping material 3 is formed of cross-linked polyethylene.

Then, as shown in FIG. 4, the sleeve tube 1a, the socket 2a, and the piping material 3 are first fitted to the hot plates 4a and 4b heated to the melting points of the crosslinked polyethylene and the non-crosslinked polyethylene. As a result, the outer peripheral surface of the connection end portion 31 of the pipe member 3, the inner peripheral surface of the pipe member fitting portion 12 of the sleeve tube 1a, the outer peripheral surface of the receptacle fitting portion 11, and the inner peripheral surface of the receptacle 24 are heated and melted. Is done. Next, after the hot plates 4a and 4b are removed from the pipe member 3, the sleeve tube 1a and the female screw socket 2a, as shown in FIG.
In a state where the molten state is maintained, the connection end portion 31 of the pipe member 3 is fitted into the pipe member fitting portion 12 of the piping member 3 of the sleeve tube 1a, and the socket fitting portion 11 of the sleeve tube 1a is configured as the socket of the female screw socket 2a. 24, the inner peripheral surface of the pipe material fitting portion 12 of the sleeve tube 1a, the outer peripheral surface of the connection end portion 31 of the piping material 3, and the socket fitting portion 1 of the sleeve tube 1a.
1 and the inner peripheral surface of the socket 24 of the female screw socket 2a are respectively fused.

Since the socket body 21 has the large-diameter portion 25 and the small-diameter portion 26, if the sleeve tube 1b is used, a small-diameter pipe member can be similarly fused to the same female screw socket 2a. Can be.

As described above, according to the connection structure, the sleeve tube 1a made of non-crosslinked polyethylene resin is
a and the pipe member 3, and the sleeve tube 1 a is thermally fused to the socket 2 a and the pipe member 3 by a heat fusion method. There is no need to provide a layer of a plastic resin on the joint surface of a pipe material made of a cross-linked thermoplastic resin, and the die cost can be reduced. Further, if a plurality of sleeve pipes having different inner diameters or different outer diameters like the sleeve pipes 1a and 1b are easily provided, it is not necessary to provide a joint for each pipe material diameter, and the manufacturing cost of the joint can be reduced.

Further, the piping member 3 and the socket body 21
However, since it is formed of crosslinked polyethylene having a gel fraction of 65% or more, it is excellent in heat resistance and creep resistance, and is useful as a connection structure for piping to which heat is applied such as hot water supply piping.

FIG. 6 shows another embodiment of the connection structure according to the present invention. As shown in FIG. 6, this connecting structure is formed by a branch 51
This embodiment is the same as the above embodiment except that the sleeve tube 1a of FIG. 1 is used to join the piping material 3 made of crosslinked polyethylene.

FIG. 7 shows a sleeve tube according to a third embodiment of the present invention. As shown in FIG. 7, the sleeve tube 1c is the same as the sleeve tube 1a except that a gear portion 14 is provided on the peripheral surface.

FIG. 8 shows a sleeve tube according to a fourth embodiment of the present invention. As shown in FIG. 8, the sleeve tube 1d is the same as the sleeve tube 1b except that a gear portion 14 is provided on the peripheral surface.

These sleeve tubes 1c and 1d are connected, for example, with a male screw socket 7 as shown in FIGS. 9 and 10 and a cross-linked polyethylene pipe member 3 having a gel fraction of 65% or more as follows. I can do it. In addition,
The male screw socket 2b is the same as the female screw socket 2a, except that the male screw cylinder 27 made of gunmetal is insert-molded when the socket body 21 is formed.

Then, the sleeve tube 1c, the male screw socket 2b and the pipe member 3 are, as shown in FIG.
The connection end 31 of the pipe member 3 is inserted into the pipe member insertion portion 12 of the sleeve tube 1c, and the socket insertion portion 11 of the sleeve tube 1c is inserted into the socket 24 of the male screw socket 2b. Next, after the pipe member 3 and the socket body 21 of the male screw socket 2b are fixed by a clamp (not shown), the sleeve 8 is rotated by a driving force of a motor (not shown).
The sleeve tube 1c is engaged with the key portion 14 of FIG. 3C, and the sleeve tube 1c is rotated around its axis by the rotational driving force of the key 8.

The rotation causes the sleeve tube 1c to rotate.
Inner peripheral surface of pipe material fitting portion 12 and connection end portion 31 of pipe material 3
After the outer peripheral surface, and the outer peripheral surface of the socket fitting portion 11 of the sleeve tube 1c and the male screw socket 2b are brought into a molten state by rotational friction heat, the rotation is stopped and the solidified state is cooled and solidified. The male screw socket 2b and the piping material 3 are fused via the sleeve tube 1c.

According to this connection structure, the same effects as those of the above-described connection structure using heat fusion are provided, and a shearing force acts on the cross-linked polyethylene at the joint interface due to rotational friction, so that the molecules of the cross-linked polyethylene are cut. In addition, entanglement of the sleeve tube 1c with the non-crosslinked polyethylene resin occurs, and a stronger connection state can be obtained. Also, since only the sleeve tube 1c is merely rotated,
As in the case of the header 5 shown in FIG. 6, rotational friction welding can also be used to connect pipe members that cannot be rotated.

The present invention is not limited to the above embodiment. For example, in the above-described embodiment, the female screw socket 2a is heat-sealed by heat fusion, and the male screw socket 2b is rotationally friction-welded.

[0032]

The sleeve tube according to the present invention and the connection structure between the pipe member and the joint using the sleeve tube are as follows:
With the above configuration, any thermoplastic resin piping material and the joint can be easily fusion-bonded without increasing the manufacturing cost of the joint.

In particular, according to the connection structure of the fourth aspect, the joining between the sleeve pipe and the piping material and the joint becomes stronger and more stable. Further, according to the connection structure of the fifth aspect, it is possible to connect a plurality of diameters of piping materials with one joint, and it is possible to reduce the number of types of joints and to reduce the manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a sleeve tube according to the present invention.

FIG. 2 is a sectional view showing a sleeve tube according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a joint to which the sleeve tube of FIG. 1 is connected.

FIG. 4 is an explanatory diagram illustrating an example of a method of connecting a joint and a piping material using the sleeve pipe of FIG. 1;

5 is a cross-sectional view showing a connection structure obtained by the connection method shown in FIG.

FIG. 6 is a sectional view showing another connection structure using the sleeve tube of FIG. 1;

FIG. 7 is a sectional view showing a sleeve tube according to a third embodiment of the present invention.

FIG. 8 is a sectional view showing a sleeve tube according to a fourth embodiment of the present invention.

9 is a sectional view of a joint to which the sleeve tube of FIG. 7 is connected.

FIG. 10 is a sectional view showing a connection structure using the sleeve tube of FIG. 7;

[Explanation of symbols]

 1a, 1b, 1c, 1d Sleeve tube 11 Receptacle fitting part 12, 13 Piping material fitting part 14 Gear part 2a Female screw socket (joint) 2b Male screw socket (joint) 24 Socket 5 Header (joint)

Claims (5)

[Claims] An external fitting is formed on one end of a pipe member connected from one end thereof and is internally fittable on a receiving port of a joint connected from the other end, and is externally fitted on at least one end of the pipe member. The inner peripheral surface of the pipe material fitting portion to be inserted and the inner peripheral surface of the socket fitting portion to be fitted in the socket of the joint can be fused with the outer peripheral surface of the fitting portion of the pipe material and the inner peripheral surface of the fitting port of the joint. Sleeve tube made of synthetic resin material. 2. The sleeve tube according to claim 1, wherein the sleeve tube is formed of a non-crosslinked polyethylene. 3. A sleeve tube according to claim 1 or 2, wherein a receiving portion of the sleeve tube is fitted into a receiving portion of the joint, and a connecting end of the piping material is fitted into the piping material fitting portion. Pipe material in which the inner peripheral surface of the pipe material fitting portion of the sleeve pipe and the outer peripheral surface of the connection end portion of the piping material, and the outer peripheral surface of the fitting portion of the sleeve tube receiving portion and the inner peripheral surface of the fitting port of the joint are respectively fused. And connection structure with fittings. 4. A sleeve pipe is formed of non-crosslinked polyethylene, at least a socket forming portion of a joint and a connection end of a pipe material are formed of crosslinked polyethylene, and a sleeve pipe, a pipe material and a joint are formed. 4. The connection structure between a pipe member and a joint according to claim 3, wherein is welded by a rotational friction welding method. 5. The connection structure between a pipe member and a joint according to claim 3, wherein the receiving port of the joint is formed so that a pipe member having a plurality of diameters can be connected.