JPH11248065A - Manufacturing method of flanged pipe - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To manufacture a flanged pipe at low cost without trouble. SOLUTION: A concave portion 1b is formed on the outer peripheral wall of a distal end portion of a pipe 1 to form a cavity for closing a pair of split molds 7 and 8 to form a flange, and a distal end portion of the pipe 1 is formed in the cavity. Position. In this state, the molten plastic material P is fed into the cavity to form a flange, and the concave portion 1 of the pipe 1 is formed.
b into the flange, and insert the pipe 1
Attach.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a pipe with a flange. More specifically, the present invention relates to a method for manufacturing a flanged pipe used for piping of an air conditioner such as an automobile.

[0002]

2. Description of the Related Art A flanged pipe used for piping such as an air conditioner usually has a flange made of aluminum or a plastic material. As a method for manufacturing such a flanged pipe, Japanese Patent Application Laid-Open No.
269750. In this method of manufacturing a pipe with a flange, the flange is formed by joining constituent members having a shape obtained by dividing the flange into two parts. A pipe fitting groove is formed at the joint between the two components, and in a state where the pipe is fitted into the two fitting grooves, the two components are fixed to each other and the flange and the pipe are combined.

[0003]

In the above-mentioned conventional method for manufacturing a pipe with a flange, it is necessary to correctly position and fix the components, so that the shape of the joint between the components becomes complicated, and There is a problem that it takes time and effort to manufacture the member, and the resulting flanged pipe becomes expensive.

An object of the present invention is to provide a method of manufacturing a flanged pipe which solves the above-mentioned problems and which can be manufactured at low cost without trouble.

[0005]

According to the method of manufacturing a pipe with a flange, one of a convex portion and a concave portion is formed on an outer surface of a peripheral wall at a tip portion of the pipe, and a pair of split dies are closed to form a flange. Forming a cavity and positioning the tip of the pipe in the cavity,
In this state, a molten plastic material is fed into the cavity to form a flange. In this manufacturing method, when a convex portion is formed in the pipe, a concave portion in which the convex portion is embedded is formed in the flange, and when a concave portion is formed in the pipe, the convex portion to be embedded in the concave portion is formed. Is formed on the flange, and the pipe is attached to the flange.

[0006] As described above, any one of the convex portion and the concave portion may be formed in the pipe, but the concave portion is easier to form and the processing cost of the pipe is lower. Further, the shape of the convex portion and the concave portion need not be particularly limited. However, if an annular convex portion or a concave portion is formed, the pipe can be attached to the flange while the pipe rotates with respect to the flange.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment will be described. In the following description, up, down, left, and right refer to up, down, left, and right in FIG.

The lower part of FIG. 1 shows a female flanged pipe manufactured by the method of the present invention. Furthermore, the upper part of FIG. 1 shows a male flanged pipe connected thereto.

The female flanged pipe is composed of two large and small aluminum pipes (1) and (2) which are provided at right and left intervals and extend in the vertical direction, and the upper ends of the pipes (1) and (2). And a flange (3) made of a plastic material having through holes (3a) (3b) into which the parts are inserted.

The distal ends of the pipes (1) and (2) are formed as receiving portions (1a) and (2a) that are gradually expanded toward the distal ends. Also, as shown in FIGS. 3A and 3B, two recesses (1b) and (2b) are formed below the receiving portions (1a) and (2a) of the pipes (1) and (2).
Are formed.

The recesses (1b) and (2b) have through holes in the flange (3).
The pipes (1) and (2) are attached to the flange (3) by embedding convex portions (3d) and (3e) formed on the peripheral walls of (3a) and (3b). In addition, a screw hole (3c) extending vertically is formed between the pipes (1) and (2) of the flange (3).

The male flanged pipe has two large and small aluminum pipes (4) and (5), which are provided at right and left intervals and extend in the vertical direction, and the ends of both pipes (4) and (5) are inserted. And a plastic material flange (6) having through holes (6a) and (6b) formed therein. The lower ends of the pipes (4) and (5) project below the flange (6), and the projecting portions are subjected to beading processing to form annular projections (4a) and (5a). A vertically extending through hole (6c) is formed between the pipes (4) and (5) of the flange (6).

In the male and female flanged pipes formed as described above, the large-diameter pipe (1) is replaced with the large-diameter pipe.
(4) into the small-diameter pipe (2) and the small-diameter pipe (5) until the annular projections (4a) and (5a) are located in the pipes (1) and (2). ) Match (6). Then, through the through hole (6c) of the flange (6), the screw hole (3c) of the flange (3)
Then, bolts (not shown) are screwed in to fix the flanges (3) and (6) to each other.

Hereinafter, a method for manufacturing a flanged pipe according to the present invention will be described with reference to FIG. In FIG. 2, the front side of the page is left, the back side of the page is right, the left side is front, and the right side is rear. That is, FIG. 2 is a view of the pipe (1) viewed from the left side in FIG. 1, and a small-diameter pipe (2) is located behind the large-diameter pipe (1).

FIG. 2 shows split dies (7) and (8) for forming the flange (3). The split molds (7) and (8) have recesses (7a) forming the front half and the rear half of the outer shape of the flange, respectively.
(8a) and a rear opening groove (7b) extending downward from the recesses (7a) and (8a).
And a front opening groove (8b). In addition, later split mold
(8) is provided with a gate (8c) communicating with the recess (8a). The cross-sectional shape of the grooves (7b) (8b) is a shape obtained by dividing the pipe (1) back and forth along its axis, that is, a semicircular shape. Although not shown, the rear opening groove (7b) in the split mold (7) and the front opening groove (8
On the right side of b), there are formed a rear opening groove and a front opening groove, each of which has a shape obtained by dividing the pipe (2) back and forth on its axis, that is, a semicircular shape.

The split molds (7) and (8) as described above are closed and the concave
(7a) (8a) forms a cavity for molding the flange (3). The tip of the pipe (1) is located in the cavity formed by the recesses (7a) and (8a), and the groove (7b) and (8b) are inserted into the grooves below the tip of the pipe (1) and split. Hold the pipe (1) by the molds (7) and (8).

Before the pipe (1) is clamped by the split molds (7) and (8), a receiving portion (1a) and a concave portion (1b) are formed at an end thereof by an appropriate processing.

Although not shown, a pipe (2) which has been processed in the same manner as the pipe (1) is located on the right side of the pipe (1), and the recesses (7a) ( The tip of the pipe (2) is located in the cavity formed by 8a), and the lower side of the tip of the pipe (2) is fitted into the groove, and the pipe is formed by split molds (7) and (8). (2) is held.

Then, in this state, the molten plastic material (P) is fed into the cavity from the gate (8c) at a high pressure. When the molten plastic material (P) is fed into the cavity, the plastic material (P) spreads in the cavity and bulges into the recess (1b) of the pipe (1) and the recess (2b) of the pipe (2). Pipe while the parts (3d) and (3e) are formed
A flange (3) is formed around (1) and the pipe (2).

Next, after the temperature of the plastic material (P) has dropped, the split molds (7) and (8) are opened, and the burrs of the flange (3) and the plastic material (P) of the gate (8c) are removed, and the flange is removed. A pipe is obtained. In this flanged pipe,
Since the flange is formed integrally, no labor for assembling the flange is required.

The shapes of the recesses (1b) and (2b) formed in the pipe (1) and the pipe (2) are not limited to the above-described circular cross-sections, but may be, for example, those shown in FIGS. Recess shown in
It may extend vertically as shown in (11b).
It may be annular like the concave portion (12b) shown in FIG. Further, the number of the concave portions is not limited to two, and FIG.
(A) As shown in FIG.
(A) As shown in (b), the number may be one. Further, it is not always necessary to form a concave portion, and a convex portion may be formed.

The flanged pipe manufactured by the method of the present invention has a female mold, that is, a socket as described above,
It is not limited to a male flanged pipe to be inserted therein, and a flange of a flanged pipe may be attached to a flange formed on a liquid receiver or the like using bolts and nuts.

For example, it is not always necessary to provide a receiving port at the tip of the pipe, and without expanding the pipe, forming a projection or a recess at the tip of the pipe having a constant diameter, and forming a flange around the pipe. You may.

[0024]

According to the method of manufacturing a flanged pipe according to the present invention, one of a convex portion and a concave portion is formed on the outer peripheral surface of the peripheral wall at the tip of the pipe, and a pair of split dies are closed to form a flange. A cavity is formed and the tip of the pipe is located in the cavity. In this state, the molten plastic material is fed into the cavity to form a flange. If a pipe with a flange embedded in a flange and a recess is formed in the pipe, a pipe with a flange in which the flange is embedded in this recess can be easily and inexpensively manufactured without a step of combining the flange and the pipe. it can.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a use state of a flanged pipe manufactured by a method for manufacturing a flanged pipe of the present invention.

FIGS. 2A and 2B are cross-sectional views showing steps of the method.

FIG. 3A is an enlarged view of a part of a flanged pipe manufactured by the same method, and FIG.
FIG. 4 is a sectional view taken along line bb in FIG.

FIG. 4A is an enlarged view of a part of a pipe in another flanged pipe manufactured by the same method, and FIG.
FIG. 5 is a sectional view taken along line bb in FIG.

FIG. 5 (a) is an enlarged view of a part of a pipe in still another flanged pipe manufactured by the same method,
FIG. 5B is a sectional view taken along line bb in FIG.

[Explanation of symbols]

 (1) (2) Pipe (1b) (2b) Convex part (3) Flange (3d) (3e) Flange embedded part

Claims (1)

[Claims] 1. One of a convex portion and a concave portion is formed on the outer surface of a peripheral wall of a tip portion of a pipe, and a cavity for forming a flange by closing a pair of split dies is formed, and a tip of the pipe is formed in the cavity. In this state, the molten plastic material is fed into the cavity to form a flange.If a convex portion is formed in the pipe, the convex portion is embedded in the flange, and a concave portion is formed in the pipe. If so, a method for manufacturing a pipe with a flange, in which a flange is embedded in the recess and the pipe is attached to the flange.