JPH0362493B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for manufacturing a three-way joint pipe used in, for example, a heat exchanger.

[Conventional technology]

The three-way joint tube used to connect the pipes of the heat exchanger has a T-shape, as shown in FIG. 7, with each end A extending in the same direction. In addition, in the figure, B is an aluminum fin and C is a pipe.

Conventionally, as a manufacturing method for this type of three-way joint pipe,
For example, as shown in FIGS. 8a, b, and c, a metal pipe 1 is processed into a bulge to bulge out its middle part, and then the head of the bulged part 1 is cut off to open the metal pipe 1. There is a known manufacturing method in which the L-shaped tube 2 is bent into a U-shape, and then the end of the L-shaped tube 2 is inserted into the opened bulged portion 1a and brazed.

According to the above method, the metal pipe 1 is bulged by filling with urethane or using hydraulic pressure.
It is very difficult to lengthen the bulge 1a and form it into a branched T-tube extending approximately the same length on three sides, resulting in poor yields and not being a problem in practice. A separately formed L-shaped tube 2 was brazed to the bulged portion 1a with a length sufficient to be used as a connection portion.

For this reason, manufacturing takes time and requires sophisticated technology, and if there is even the slightest defect in the brazed portion, there is a problem that leakage may occur after long-term use. There was also the problem that the flow of the refrigerant was disturbed by the stepped portion formed on the inner wall of the pipe at the brazed portion.

[Problem to be solved by the invention]

The present invention provides an apparatus for manufacturing a T-tube having a shape in which the branched pipe portions are bent in the same direction with respect to a T-tube branched into three directions.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a T-tube in which a groove with a semicircular cross section is formed to support each tube part of a T-tube branched to extend in three directions of a metal pipe.
At the intersection of the T-shaped support and the tube portion of the T-shaped tube placed on the T-shaped support, each tube of the T-shaped tube is arranged perpendicularly to the T-shaped support on the side. and a presser mold member having a groove with a semicircular cross section facing the part, and the T-shaped support base allows the tube portion to be placed along the grooves on each side of the presser mold member around the branching part thereof. A piston rod is configured to be rotatable so as to be able to rotate freely, and a mandrel inserted into each tube section located in a groove having a semicircular cross section that supports each tube section of the T-shaped tube is fixed to an end of a support base. It is characterized by being movable along the

[Effect]

According to the configuration of the present invention, a metal pipe of a T-shaped tube branched into three directions is set on a T-shaped support base, and the T-shaped support is rotated around the lower end of the holding member disposed at the branching part of the metal pipe. It is possible to provide a manufacturing device for a three-way joint pipe that can manufacture a three-way joint pipe by rotating a table, shortens manufacturing time, and is free from leakage and does not cause disturbances in the flow of refrigerant or the like.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in FIG. 3, a metal pipe 5 cut to an appropriate length is filled with a molten filler 6 made of a soft metal material with a lower melting point than the metal material forming the metal pipe 5. .

As the metal pipe 5, for example, a copper pipe is used, and as the filler material 6, lead is used. Further, when filling the filler 6, air is removed so as not to form a cavity. In addition, filler material 6
Instead of melting and filling the metal pipe 5
A rod-shaped filler 6 having a diameter matching the inner diameter of the metal pipe 5 may be formed and press-fitted into the metal pipe 5.

When the filler 6 is solidified and cooled to about room temperature, the metal pipe 5 is inserted into the cavity 7 of a mold 8 having a T-shaped cavity 7, as shown in FIG.
Set inside. Then, the filling material 6 is pressed from the openings at both ends of the metal pipe 5 by pressing members 9 connected to a hydraulic cylinder (not shown).

As a result, the metal pipe 5 is filled with the filler 6.
As shown in FIG. 5, the middle portion thereof is bulged into the empty cavity portion 7a, and is formed into a T-shape branched to extend approximately the same length on three sides.

In conventional bulge processing, it was performed by filling molding using urethane as a filler or by hydraulic molding using pressurized oil, so it was very difficult to lengthen the bulging portion 1a. In the above embodiment, since a soft metal material such as lead is used as a filler, the bulge can be lengthened without any problem.

In other words, when urethane is used as a filler, there is the disadvantage that the urethane itself is compressed, and when pressurized oil is used, it must be pressurized in a sealed state to prevent the pressurized oil from leaking from the openings at both ends. First, if the pressure is increased in order to lengthen the bulging portion 1a, pressurized oil inevitably leaks from the openings at both ends of the metal pipe, and in both cases, it is difficult to apply sufficient pressure to the bulging portion 1a. It was hot.

On the other hand, when using soft metal materials such as lead, there is no inconvenience that the material itself is compressed.
Further, there is no problem of pressurized oil leaking, and the bulge can be bulged by applying sufficient pressure to the bulge.

As mentioned above, after forming the metal pipe 5 into a T-shape, the head of the bulging part is cut off and the whole is filled with the filler 6.
The filler material 6 is melted by heating to a temperature higher than the melting point of the filler material. At this time, heating serves as annealing, and work hardening during molding is removed. Therefore, there is no need to perform annealing after each molding process. As a result, a T-shaped tube 10 as shown in FIG. 6 is manufactured.

Next, the branch portions of the three-way branched tube portions 10a of this T-tube 10 are fixed, and the three-way branched tube portions 10a, 10a, 10a are bent in the same direction.

Figures 1a and 1b show a bending machine of the invention for bending a T-tube 10 as described above.

The bending machine has each pipe section 10a, 10
A groove 11a with a semicircular cross section supporting the grooves 11a and 10a
is formed, and support stands 11, 11, 11 arranged in a T-shape having the same shape as the T-shaped tube 10, and grooves 12a each having a semicircular cross section are formed on three sides, so that when the T-shaped tube is bent, 10, and a holding member 12 for fixing the branched portions of the tube portions 10 that are branched into three directions. Support stands 11, 11, 1 arranged in a T-shape
1 is a holding mold member 1 centered around the branching part of each tube part 10.
It can be rotated so that it can face the two sides.

Further, a guide shaft 13 is fixed to the end face of each support stand 11, and a movable plate 14 is movably mounted on this guide shaft 13. And this moving plate 14
An end of a piston rod 16 of a hydraulic cylinder 15 fixed to the lower surface of the support base 11 is fixed to the lower part of the piston, and an end of a mandrel 17 to be inserted into the pipe part 10a is fixed to the upper part. cylinder 15
The mandrel 17 can be moved to a predetermined position within the tube portion 10a.

In order to bend each tube section 10a of the T-tube 10 in the same direction using the bending machine of the present invention, each tube section 10a is set in the groove 11a, and the branch section of the T-tube 10 is bent by the holding member 12. fixed on top,
Next, each hydraulic cylinder 15 is operated to open each pipe portion 1.
After inserting the mandrel 17 into the holder 0a, each support stand 11 is rotated toward the groove 12a of the presser mold member 12 using the branch part of the T-shaped tube 10 as a fulcrum, so that each tube portion 10a is It is fitted into the groove 12a of the mold member 12. Thereby, each tube portion 10a of the T-shaped tube 10 is bent as shown in FIG. 2, and a three-way joint tube is formed.

In this way, when the T-shaped tube 10 is bent with the branched portion fixed at the end of the holding member 12, the T-shaped tube 10 is bent evenly around the branched portion, and each tube portion 10 is bent evenly around the branched portion.
The length of a can be made constant. In the conventional three-way joint pipe, in order to bend the metal pipe 1 into a U-shape after bulge processing, one end of the metal pipe 1 is fixed to a holding member, and the other end is attached to the holding member. It was pressed against the presser mold member side. In other words, since the middle part of the metal pipe 1 was bent without being fixed, one end and the other end were not aligned (at this time, the bulging part 1a was slightly shifted from the middle part of the U-shaped pipe). ), it was necessary to align them after bending.

As explained above, according to the three-way joint pipe manufacturing apparatus of the present invention, a T-shaped pipe in which a metal pipe is branched into three directions with substantially the same length is supported on a support using a filler made of a soft metal material. The end of the holding mold member is fixed to the branching part of this T-shaped tube, and the support base is rotated around the end of this holding mold member toward the groove of the holding mold member. At this time, the tube portion of the T-tube can be reinforced and bent while moving the tip of the mandrel.

In the present invention, the T-tube is formed using a filler that has a lower melting point than the material of the metal pipe, and when the filler is removed from the metal pipe, it is heated and melted, so this heating is required for annealing. It is possible to eliminate work hardening during molding, and is convenient for bending in a bending machine.

Unlike conventional three-way joint pipes, the present invention does not require brazing work, reducing manufacturing time, and eliminates leakage from brazed parts, which causes disturbances in the flow of refrigerant, etc. Never.

〔effect〕

According to the configuration of the present invention, a T-shaped pipe formed by branching a metal pipe into three directions with substantially the same length can be formed efficiently using a bending machine in a short time, and a highly accurate three-way joint pipe can be formed. can be manufactured.

[Brief explanation of drawings]

Figures 1a and b are side views and sectional views showing the manufacturing apparatus of the present invention, Figure 2 is a perspective view of a three-way joint pipe manufactured by the manufacturing apparatus of the present invention, and Figure 3 is a metal pipe filled with filler. Cross-sectional view showing the filled state, No. 4,
Figure 5 is a cross-sectional view showing the manufacturing equipment and its operation for turning metal pipes into T-tubes, Figure 6 is a cross-sectional view of the T-tube manufactured by the T-tube manufacturing equipment, and Figure 7 is used for heat exchangers. A perspective view of the three-way joint pipe, Fig. 8a,
b and c are explanatory diagrams illustrating a conventional method for manufacturing a three-way joint pipe. DESCRIPTION OF SYMBOLS 10...T-shaped tube, 10a...tube part, 11...support stand,
11a... Groove of support base, 12... Presser mold member, 12a
...Groove of presser mold member, 13...Guide shaft, 14...Moving plate, 15...Hydraulic cylinder, 16...Piston rod, 17...Mandrel.

Claims (1)

[Claims] 1. A T-shaped support base having a groove with a semicircular cross section that supports each tube part of a T-shaped pipe branched into three directions, and a T-shaped support base placed on the T-shaped support base. A holding member that is arranged perpendicularly to the T-shaped support at the intersection of the pipe parts of the T-tube and has a groove with a semicircular cross section facing each pipe part of the T-tube on its side surface. The T-shaped support base is configured to be rotatable around the branching portion thereof so that the tube portion can be placed along the grooves on each side of the holding mold member, and each tube portion of the T-shaped tube A three-way joint characterized in that a mandrel inserted into each pipe portion located in a groove with a semicircular cross section that supports the piston rod is movable along a piston rod fixed to an end of a support base. Pipe manufacturing equipment.