JP2013104465A - Method for manufacturing multi-way pipe joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a multi-way pipe joint, by which problems such as a working environment and lead pollution are remedied.SOLUTION: The method for manufacturing a multi-way pipe joint includes: a step of inserting a bar-like resin material 2 into a copper pipe 1; a step of setting the copper pipe 1 in a molding chamber inside a die; a step of swelling an intermediate part of the copper pipe 1 by pressurizing from both sides of the copper pipe 1 via the resin material 2; a step of cutting the apical end of the swelled portion; and a step of crashing the resin material 2 and relieving it from the copper pipe 1.

Description

  The present invention relates to a method for manufacturing a multi-way pipe joint from a metal pipe.

  Three-way joint pipes (corresponding to multi-way pipe joints) are used for connecting pipes of heat exchangers such as air conditioners. As a manufacturing method of such a three-way joint pipe, a manufacturing method of a multi-way different diameter pipe joint disclosed in Patent Document 1 below is known.

  In this manufacturing method, a metal pipe is filled with a filler made of a soft metal material having a melting point lower than that of the metal material forming the metal pipe, and the metal material is set in a mold, from both ends of the metal pipe. The method includes a step of pressurizing the filler to swell the substantially central portion of the metal pipe, and a step of heating to melt only the filler.

Japanese Examined Patent Publication No. 7-106407

  However, the manufacturing method according to the above prior art has the following problems. That is, lead is used as a filler, which causes a problem of lead pollution. In addition, a furnace is required to melt lead, and there are problems in terms of equipment cost and work environment.

  This invention is made | formed in view of the said situation, The subject is providing the manufacturing method of the multiway pipe joint which improved the problem of work environment or lead pollution.

In order to solve the above problems, a method for manufacturing a multi-way pipe joint according to the present invention is as follows.
Inserting a rod-shaped resin material into the metal pipe;
Setting the metal pipe in a molding chamber inside the mold; and
A step of bulging an intermediate portion of the metal pipe by pressurizing from both ends of the metal pipe through the resin material;
Cutting the tip of the bulging part;
And crushing the resin material and removing it from the metal pipe.

  The operation and effect of the manufacturing method of the multiway pipe joint having such a configuration will be described. First, a metal resin pipe is filled with a rod-shaped resin material. Next, this metal pipe is set in a mold, and a resin material is pressurized from both ends of the metal pipe. Thereby, the center part of a metal pipe is bulged. The bulging tip is cut, and the resin material filled in the metal pipe is crushed and removed from the metal pipe. By using a resin material, there is no need for a melting furnace as in the prior art, and there is no problem of pollution. Therefore, the manufacturing method of the multiway pipe joint which improved the problem of work environment or lead pollution can be provided.

  It is preferable that the method further includes a step of heating the metal pipe after the crushing step according to the present invention. By heating the metal pipe, the resin material remaining on the inner surface of the metal pipe can be removed.

Flow chart showing manufacturing process Diagram showing the manufacturing process of a three-way joint pipe Diagram showing the manufacturing process of a three-way joint pipe Diagram showing the manufacturing process of a three-way joint pipe Diagram showing the manufacturing process of a three-way joint pipe Diagram showing the manufacturing process of a three-way joint pipe Diagram showing the configuration of the bending machine External view showing molded three-way joint pipe External view showing another embodiment of molded three-way joint pipe

  A preferred embodiment of a method for manufacturing a multiway pipe joint according to the present invention will be described with reference to the drawings. A process for producing a three-way joint pipe as a multi-way pipe joint will be described as an example. FIG. 1 is a flowchart illustrating a manufacturing process, and FIGS. 2A to 2E are diagrams illustrating a manufacturing process using a metal pipe.

<Manufacturing process>
First, the copper tube 1 (corresponding to a metal pipe) is cut to an appropriate length (S1 in FIG. 1, FIG. 2A). The chips adhering to the copper tube 1 are washed and removed (S2). Next, a rod-shaped (cylindrical) filler 2 is filled (inserted) into the copper tube 1 (S3, FIG. 2B). The resin material 2 having the same length as the copper tube 1 can be used. In addition, the outer diameter of the resin material 2 is slightly smaller than the inner diameter of the copper tube 1. The resin material 2 is not limited to a specific type of resin, and a general-purpose resin material (for example, polycarbonate) can be used.

  Next, the copper tube 1 filled with the resin material 2 is set in a molding space inside the mold and molded into a T-shape (S4, FIG. 2C). As shown in FIG. 2C, the mold 3 is formed with a T-shaped molding space, and includes a small-diameter portion 30 and a large-diameter portion 31 branched from the center of the small-diameter portion 30. The inner diameter of the large diameter part 31 is set to about 1.5 times the inner diameter of the small diameter part 30, for example. Further, the inner diameter of the small diameter portion 30 is set to be slightly larger than the outer diameter of the copper tube 1. The large diameter portion 31 of the mold 3 is connected to the small diameter portion 33 via the tapered portion 32.

  Next, pressure is applied from both ends of the copper tube 1 through the resin material 2. FIG. 2C shows a state before pressurization, and FIG. 2D shows a state after pressurization. In order to pressurize, the pressing member 4 is provided, and the pressing force by a hydraulic cylinder is given. As the hydraulic cylinder, for example, a high output cylinder of about 100 t can be used.

  As a result, the copper tube 1 bulges toward the large diameter portion 31 as shown in FIG. The bulging portion 1a bulges until it comes into contact with the branched small diameter portion 33. As a result, the copper tube 1 is formed into a T shape along the forming space (S4, FIG. 2E). The bulging portion 1a has an outer diameter that is larger than that of the small-diameter portion 1b.

  Next, the molded copper tube 1 is taken out from the mold 3. Since the tip portion 1c of the bulging portion 1a of the copper tube 1 is in a closed state, this portion is cut (S5). Thereby, a three-way joint pipe (T-shaped pipe T) as shown in FIG. 2E is formed. At this time, the inside of the copper tube 1 is still filled with the resin material 2 and needs to be removed. Therefore, as shown in FIG. 2E, a drill is inserted from three directions P1, P2, and P3 to grind the resin material 2 and remove it from the inside of the copper tube 1 (S6).

  Even if pulverized with a drill, it is difficult to completely remove the resin material 2 adhering to the inner surface of the copper tube 1. Therefore, the copper tube 1 is heated with a burner (S7), and the remaining resin material 2 is burned to be completely removed.

  Since lead is not used as a filler as in the prior art, a furnace for melting lead is unnecessary, and equipment costs and manufacturing costs can be reduced. Moreover, since lead is not used, there is no problem of lead pollution, and the environment can be considered. The pulverized resin is subjected to recycling.

  Next, a three-way joint pipe having a final product shape is formed. That is, each small diameter portion 1b branched in three directions is bent in the same direction.

  3A and 3B show a bending apparatus for forming a three-way joint pipe by bending the T-shaped pipe T as described above. This device includes three support bases 8 arranged in a T-shape with grooves 8a having a semicircular cross section for supporting the bulging portion 1a and the left and right small-diameter portions 1b, and half cross sections on three sides. A circular groove 9a is formed, and is composed of a small-diameter portion 1b that branches into three sides of the T-tube T when bent and a presser-type member 9 that fixes the branch portion of the bulging portion 1a. Each support base 8 is configured to rotate independently about the small-diameter pipe portion 1b or the bulging portion 1a branched in two directions of the T-shaped tube T.

  A guide shaft 10 is fixed to the end surface of each support base 8, and a movable plate 11 is movably provided on the guide shaft 10. An end portion of the piston rod 13 of the hydraulic cylinder 12 fixed to the lower surface of the support base 8 is fixed to the lower portion of the moving plate 11, and inserted into the small diameter portion 1b and the bulging portion 1a on the upper portion. The end of the mandrel 14 is fixed, and the mandrel 14 is moved and operated by the hydraulic cylinder 12.

  In order to bend the necessary small-diameter portion 1b of the T-shaped tube T by the bending apparatus, the bulging portion 1a and each small-diameter portion 1b are set in the groove 8a, and divided into three sides of the T-shaped tube T by the presser mold member 9. The branch portions of the branched portion 1a and the small-diameter portion 1b are fixed, and then each hydraulic cylinder 12 is operated to insert the mandrel 14 into the bulged portion 1a and each small-diameter portion 1b, and then support the small-diameter portion 1b. Each support base 8 to be rotated is rotated in the same direction with the three branch portions of the T-shaped tube T as fulcrums, and the small-diameter portion 1b is inserted into the groove 9a of the presser-type member 9. As a result, as shown in FIG. 4, two small-diameter pipe portions 1b, 1b of the T-shaped tube are bent at substantially right side surfaces, and a three-way joint pipe in which the large-diameter pipe portion 1a is positioned at the middle portion is formed ( S8, FIG. 4).

  The molded three-way joint pipe is washed (S10), product inspection is performed (S11), and packing is performed (S13).

<Another embodiment>
The three-way joint pipe is not limited to the above-described embodiment. For example, the present invention can be applied to a Y-shaped joint pipe as shown in FIG. Further, the multi-way pipe joint according to the present invention is not limited to a three-way joint pipe, and may be a four-way or more joint pipe.

  In the present embodiment, the copper pipe 1 has been described as an example, but an aluminum pipe and other metals can also be applied as the metal pipe.

DESCRIPTION OF SYMBOLS 1 Copper pipe 2 Resin material 1a Bumping part 1b Small diameter part 3 Mold

Claims (2)

Inserting a rod-shaped resin material into the metal pipe;
Setting the metal pipe in a molding chamber inside the mold; and
A step of bulging an intermediate portion of the metal pipe by pressurizing from both ends of the metal pipe through the resin material;
Cutting the tip of the bulging part;
And crushing the resin material and removing the resin material from the metal pipe. The method for producing a multi-way pipe joint according to claim 1, further comprising a step of heating the metal pipe after the crushing step.

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