JPH08285168A - Branch pipe joint and its manufacture - Google Patents

Abstract

PURPOSE: To provide a branch pipe joint by which rigidity of a rising branch part and fusing joining strength of the rising branch part and a short pipe can be enhanced. CONSTITUTION: A branch pipe joint A is constituted in such a way that a rising branch part 2 is arranged on a pipe wall of a main pipe 1 and an end surface of a short pipe 3 is fused on and joined to the tip of its rising branch part 2 and the rising branch part 2 is composed of an integral rising part 11 integrally molded with the pipe wall of the main pipe 1 and an auxiliary member 4 which is molded separately from the pipe wall of the main pipe 1 and is brought into close contact with and fixed to an inner peripheral surface of the integral rising part 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a branch pipe joint used in a branch portion of a pipe and a method for manufacturing the branch pipe joint.

[0002]

2. Description of the Related Art As a method for manufacturing a branch pipe joint, a hole is formed in a wall of a thermoplastic resin pipe, a peripheral portion of the hole is heated and softened, and then a molding die having an outer diameter larger than the diameter of the hole is formed. After being inserted into the thermoplastic resin tube and pulled up from the hole, the peripheral portion of the hole is raised, the molding die is taken out of the thermoplastic resin tube, and then the rising portion of the thermoplastic resin tube. A known method is to cut and flatten the tip of a flat tube, and then heat-melt and abut the flattened tip of the rising section and the tip of a short tube of approximately the same diameter as the rising section to perform fusion bonding. (See Japanese Patent Laid-Open No. 3-251449).

Since this method can be manufactured by using a thermoplastic resin tube which is usually used for piping for water supply and sewerage as a material, the branch pipe joint can be manufactured at a very low cost as compared with the manufacturing method by injection molding. It is the preferred method that can be manufactured.

[0004]

However, in such a conventional manufacturing method, the rising branch portion of the branch pipe joint is formed by the rising portion formed by stretching the pipe wall of the thermoplastic resin pipe, Since the main pipe of the branch pipe joint is formed in the portion other than the rising portion of the plastic resin pipe, the branch pipe joint manufactured by this manufacturing method is
The wall thickness of the rising branch becomes much thinner than that of the main pipe, the rigidity of the rising branch is extremely lower than the rigidity of the main pipe, and moreover, the tip of the rising branch and the end face of the short pipe are The fusion splicing strength between them had become weak.

Further, in the above-mentioned conventional manufacturing method, after the molding die is taken out of the thermoplastic resin tube, it is prevented that the rising portion tries to return to the original shape due to the material characteristics of the thermoplastic resin tube. Since there is nothing left, it is difficult to stabilize the shape of the rising branch portion.

In view of the above problems, the present invention provides a branch pipe joint which can improve the rigidity of the rising branch portion and the fusion bonding strength of the rising branch portion and the short pipe. A first object is to easily manufacture a branch pipe joint in which the rigidity of the rising branch portion and the fusion bonding strength of the rising branch portion and the short pipe can be improved, and the shape of the rising branch portion is stable. A second object is to provide a manufacturing method capable of achieving the above.

[0007]

In order to achieve the above first object, in the branch pipe joint according to the first aspect of the present invention, a rising branch portion is provided on the pipe wall of the main pipe, and the leading end of the rising branch portion is provided. In the branch pipe joint configured by fusion-bonding the end faces of the short pipe, the rising branch portion,
An integral rising portion integrally molded with the pipe wall of the main pipe,
The auxiliary member is formed separately from the pipe wall of the main pipe and is closely fixed to the inner peripheral surface of the integral rising portion.

In order to achieve the second object,
In the method for manufacturing a branch pipe joint according to the second aspect of the present invention, after forming a hole in the pipe wall of the thermoplastic resin pipe and heating and softening the peripheral portion of the hole, the outer diameter is larger than the diameter of the hole. By inserting the mold into the inside of the thermoplastic resin pipe in a state of being fitted inside the auxiliary member formed in a shape along the outer peripheral surface of the mold and pulling up from the hole,
While raising the peripheral portion of the hole, the outer peripheral surface of the auxiliary member is closely fixed to the inner peripheral surface of the integral rising portion,
Then, the molding die is detached from the auxiliary member and taken out of the thermoplastic resin tube, and the tip of the integral rising portion of the thermoplastic resin tube and the tip of the auxiliary member are flatly cut to form the integral rising portion. Has an inner diameter substantially equal to the inner diameter of the auxiliary member and an outer diameter substantially equal to the outer diameter of the auxiliary member, and the tip of the integrally rising portion that is evenly cut and the auxiliary. The tip of the member is fusion-bonded by heating and melting and abutting.

[0009]

In the branch pipe joint according to the first aspect of the present invention, the rising branch portion is integrally formed with the pipe wall of the main pipe, and the rising pipe is formed separately from the pipe wall of the main pipe. Since the auxiliary member is fixed to the inner peripheral surface of the auxiliary member, the thickness of the rising branch portion can be appropriately set according to the thickness of the auxiliary member. That is, it is possible to easily make the wall thickness of the rising branch portion substantially the same as the wall thickness of the main pipe or thicker than the wall thickness of the main pipe.

In the branch pipe joint manufacturing method according to the second aspect of the present invention, the rising branch portion of the branch pipe joint is formed by the integral rising portion of the thermoplastic resin pipe and the auxiliary member, and the integral rising portion of the thermoplastic resin pipe is formed. The main pipe of the branch pipe joint is formed in a portion other than the portion. Since the integral rising portion of the thermoplastic resin pipe is formed by stretching the pipe wall of the thermoplastic resin pipe, it is thinner than the thickness of the main pipe, but the thickness of the lacking portion is reduced by the auxiliary member. Since it can be compensated for, the wall thickness of the rising branch portion, that is, the thickness of the integral rising portion of the thermoplastic resin pipe and the auxiliary member is almost the same as the wall thickness of the main pipe, or the wall thickness of the main pipe. Can be thicker than

In the method for manufacturing a branch pipe joint according to the second aspect of the present invention, the molding die is inserted into the inside of the thermoplastic resin pipe in a state of being fitted inside the auxiliary member and is pulled up from the hole. Since the outer peripheral surface of the auxiliary member is tightly fixed to the inner peripheral surface of the integrally rising portion of the thermoplastic resin tube while the peripheral portion of the hole is raised, even if there is some variation in the shape of the auxiliary member, Since the shape of the integral rising portion corresponds to the shape of the auxiliary member, the inner peripheral surface of the integral rising portion and the outer peripheral surface of the auxiliary member are securely and firmly fixed to each other. That is, as a method of manufacturing a similar branch pipe joint, a method of forming an integral rising portion and then inserting an auxiliary member into the inside of the thermoplastic resin pipe and closely fixing to the inner peripheral surface of the integral rising portion can be considered. Compared to this method, the work of closely fixing the inner peripheral surface of the integrally rising portion and the outer peripheral surface of the auxiliary member is extremely easy.

Further, in the method for manufacturing a branch pipe joint according to the second aspect of the present invention, since the shape of the integral rising portion is maintained by the auxiliary member even after the molding die is taken out of the thermoplastic resin pipe, the rising branch is formed. The shape of the part is stable.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the construction of a branch pipe joint according to an embodiment of the present invention will be described with reference to FIG.

The branch pipe joint A of this embodiment is formed of a thermoplastic resin, and as shown in the longitudinal sectional view of FIG. 1, it is formed on the pipe wall of the main pipe 1 at right angles to the axial center of the main pipe 1. A rising branch portion 2 is provided, and at the tip of the rising branch portion 2,
The end surface of the short pipe 3 is configured by fusion bonding.

The rising branch portion 2 is formed separately from the integral rising portion 11 integrally formed with the pipe wall of the main pipe 1, and is formed separately from the pipe wall of the main pipe 1 on the inner peripheral surface of the integral rising portion 11. With the auxiliary member 4 fixed,
It is formed to have substantially the same thickness as the main pipe 1 as a whole.
The auxiliary member 4 is provided on the inner peripheral surface of the main pipe 1 at the periphery of the rising branch portion 2 and the cylindrical portion 41 fixed to the inner peripheral surface of the integral rising portion 11 and at one end of the cylindrical portion 41. The enlarged diameter portion 42 is formed so as to extend along the trumpet shape, and the enlarged diameter portion 42 is formed so as to gradually become thinner toward the tip. Further, the auxiliary member 4 is formed of the same material as the integral rising portion 11.

That is, in this branch pipe joint A, since the main pipe 1 and the rising branch portion 2 are formed to have substantially the same wall thickness, the rigidity of the rising branch portion 2 and the length of the rising branch portion 2 are short. It is easy to improve the fusion bonding strength of the pipe 3 as compared with the conventional branch pipe joint.

Next, a method of manufacturing the branch pipe joint A will be described with reference to FIGS.

In the case of manufacturing the branch pipe joint A, first, as shown in FIG. 2, a hole 1 is formed in a pipe wall of a thermoplastic resin pipe (vinyl chloride resin pipe, ABS resin pipe, acrylic pipe, etc.) 10.
Open 01. The shape of the hole 101 may be circular, or may be oval long in the axial direction of the thermoplastic resin tube 10.

Next, a hot melt adhesive is applied to the inner surface of the peripheral portion of the hole 101, and the peripheral portion of the hole 101 is heated and softened. As a heating means, a rubber heater, a gas burner, a far infrared heater or the like can be used, but in consideration of the stabilization of the heating area and the ease of uniformizing the heating temperature in the heating area, the rubber heater is used. The method of heating by contacting the outer peripheral surface of the thermoplastic resin tube 10 is the most suitable.

Next, with the peripheral portion of the hole 101 being heated and softened, a molding die 5 having an outer diameter larger than the diameter of the hole 101 is fitted inside the auxiliary member 4, as shown in FIG. By inserting the thermoplastic resin pipe 10 inside the thermoplastic resin pipe 10 and pulling it up from the hole 101, the hole 10
The outer peripheral surface of the auxiliary member 4 is tightly fixed to the inner peripheral surface of the integral rising portion 11 thus formed. The fixing of the inner peripheral surface of the integral rising portion 11 and the outer peripheral surface of the auxiliary member 4 is ensured by the adhesive applied to the inner surface of the peripheral portion of the hole 101 in advance.

Here, since the integral rising portion 11 of the thermoplastic resin pipe 10 is formed by stretching the pipe wall of the thermoplastic resin pipe 10, it is thinner than the other portions. However, since the auxiliary member 4 is formed to have a thickness and a shape that compensate for the lack of the wall thickness of the integral rising portion 11 as compared with the thickness of other portions, the integral rising portion 11 The total thickness of the reinforcing member 4 and the reinforcing member 4 is almost the same as the thickness of the portion of the thermoplastic resin pipe 10 other than the integral rising portion 11.

Even if there is some variation in the shape of the auxiliary member 4, the shape of the integral rising portion 11 corresponds to the shape of the auxiliary member 4 when the peripheral edge of the hole 101 is raised. The inner peripheral surface of the one-piece rising portion 11 and the outer peripheral surface of the auxiliary member 4 are securely and closely fixed. That is, as a method of manufacturing a similar branch pipe joint, after forming the integral rising portion 11, the auxiliary member 4 is inserted inside the thermoplastic resin pipe 10 and the integral rising portion 1 is formed.
Although a method of closely fixing to the inner peripheral surface of No. 1 can be considered, the work of closely fixing the inner peripheral surface of the integral rising portion 11 and the outer peripheral surface of the auxiliary member 4 is extremely easy as compared with this method.

It is preferable that the inner peripheral surface of the auxiliary member 4 and the outer peripheral surface of the molding die 5 have substantially the same shape, and they are in close contact with each other. Further, the auxiliary member 4 may be formed by injection molding, or may be formed by expanding the diameter of the tube while heating and softening the tube.

After that, as shown in FIG.
Of the thermoplastic resin pipe 1 by separating the thermoplastic resin pipe 1 from the auxiliary member 4.
Take it out of 0. At this time, a force to return to the original shape is generated in the integral rising portion 11 due to the material characteristics of the thermoplastic resin tube 10. Against this force, the auxiliary member 4
Is repulsed, the shape of the integral rising portion 11 is maintained as it is when the molding die 5 is pulled up.

Next, as shown in FIG. 5, the tip of the integrally rising portion 11 of the thermoplastic resin tube 10 and the tip of the auxiliary member 4 are flatly cut.

The auxiliary member 4 has an inner diameter which is substantially equal to the inner diameter of the integral rising portion 11.
Of the thermoplastic resin short tube 3 having an outer diameter substantially equal to the outer diameter, and the tip of the integral rising portion 11 and the tip of the auxiliary member 4 that are evenly cut,
As shown in FIG. 6, it is brought into contact with the heater 6 to be heated and melted, and further, as shown in FIG. The bead generated at the joint is cut off if necessary.

As a result, the branch pipe joint A is completed. In the branch pipe joint A manufactured in this manner, the rising branch portion 2 is formed by the integral rising portion 11 of the thermoplastic resin pipe 10 and the auxiliary member 4, and other than the integral rising portion 11 of the thermoplastic resin pipe 10. Since the main pipe 1 is formed in the portion, the wall thickness of the rising branch portion 2 and the wall thickness of the main pipe 1 are substantially the same. In addition, the shape of the rising branch 2 is also very stable.

That is, in the manufacturing method of this embodiment,
It is easy to improve the rigidity of the rising branch portion 2 and the fusion bonding strength between the rising branch portion 2 and the short pipe 3 as compared with the conventional branch pipe joint, and the rising branch portion 2
The branch pipe joint A having a stable shape can be easily manufactured.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific structure is not limited to this embodiment, and there are design changes and the like within the scope not departing from the gist of the present invention. Also included in the present invention. For example, in the embodiment, an example in which the rising branch portion is formed by the integral rising portion and the auxiliary member to have substantially the same thickness as the main pipe, but by adjusting the thickness of the auxiliary member, the rising The wall thickness of the branch portion may be thicker than the wall thickness of the main pipe. Further, in the embodiment, the branch pipe joint in which the rising branch portion is provided at a right angle to the axis of the main pipe is shown,
The rising branch portion may be provided obliquely with respect to the axis of the main pipe.

[0030]

As described above, in the branch pipe joint according to the first aspect of the present invention, since the wall thickness of the rising branch portion can be appropriately set by the wall thickness of the auxiliary member, the rising branch portion. It is possible to easily improve the rigidity of the pipe, and it is also possible to easily improve the fusion bonding strength between the rising branch portion and the short pipe.

Further, in the method for manufacturing a branch pipe joint according to the second aspect of the present invention, the rigidity of the rising branch portion and the fusion bonding strength between the rising branch portion and the short pipe can be improved, and The effect that the branch pipe joint in which the shape of the rising branch portion is stable can be easily manufactured is obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing a branch pipe joint of an embodiment.

FIG. 2 is an explanatory diagram of a manufacturing process of the branch pipe joint of the embodiment.

FIG. 3 is an explanatory diagram of a manufacturing process of the branch pipe joint of the embodiment.

FIG. 4 is an explanatory diagram of a manufacturing process of the branch pipe joint of the embodiment.

FIG. 5 is an explanatory diagram of a manufacturing process of the branch pipe joint of the embodiment.

FIG. 6 is an explanatory diagram of a manufacturing process of the branch pipe joint of the embodiment.

FIG. 7 is an explanatory diagram of a manufacturing process of the branch pipe joint of the embodiment.

[Explanation of symbols]

 A Branch pipe joint 1 Main pipe 10 Thermoplastic resin pipe 11 Integrated rising part 101 Hole 2 Standing branch part 3 Short pipe 4 Auxiliary member 5 Mold

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Claims (2)

[Claims] 1. A branch pipe joint in which a rising branch portion is provided on a pipe wall of a main pipe, and an end face of the short pipe is fusion-bonded to a tip of the rising branch portion, wherein the rising branch portion comprises: It is composed of an integral rising portion integrally formed with the pipe wall of the main pipe, and an auxiliary member formed separately from the pipe wall of the main pipe and closely fixed to the inner peripheral surface of the integral rising portion. A branch pipe joint characterized by the above. 2. A hole is formed in a pipe wall of a thermoplastic resin pipe, and a peripheral portion of the hole is heated and softened, and then a molding die having an outer diameter larger than the bore diameter of the hole is formed on the outer peripheral surface of the molding die. By inserting the inside of the thermoplastic resin pipe in a state of being fitted inside the auxiliary member formed along the shape and pulling up from the hole, while raising the peripheral portion of the hole,
The outer peripheral surface of the auxiliary member is tightly fixed to the inner peripheral surface of the integrally rising portion, and then the molding die is detached from the auxiliary member and taken out of the thermoplastic resin tube to integrate the thermoplastic resin tube. The leading end of the rising portion and the leading end of the auxiliary member are evenly cut to have an inner diameter substantially equal to the inner diameter of the integral rising portion and an outer diameter substantially equal to the outer diameter of the auxiliary member. A method for manufacturing a branch pipe joint, characterized in that the tip of the pipe, the tip of the integrally raised portion that is evenly cut flat, and the tip of the auxiliary member are heat-melted and abutted to each other for fusion bonding.