JPH0199717A - Method for manufacturing extrusion die for flat multi-hole pipe - Google Patents

Abstract

PURPOSE:To improve precision of the die and to reduce manufacturing cost by working divided hole parts in line at one side edge of divided electrode material by wire cut electrical discharge machining, then by performing the electrical discharge machining on a male die material by one pair of divided electrode material. CONSTITUTION:The electrode material 1 for making the male die is prepared as divided electrode materials 1a, 1b separated at the position from the central part of the hole line parts 2 to be divided into two parts. A number of facing- shaped divided hole parts 2a, 2b are formed on the one side edge of the electrode material 1a, 1b by the wire cut electrical discharge machining. At this time, because the divided hole parts are opened to the side face, this molding work is enabled continuous working by single wire in the state with one stroke of the brush. By this method, the working of the electrode materials 1a, 1b is improved in the precision and efficiency. Therefore, when the electrical discharge machining of the male die material 8 is performed by the electrode material 1a, 1b, the precision of the die is improved and its manufacturing cost is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to the manufacture of dies used for extrusion of flat multi-hole tubes made of aluminum or the same alloy used as tube materials for heat exchangers, that is, so-called harmonica tubes. The present invention relates to a method, in particular a processing method for manufacturing a male die thereof.

2. Description of the Related Art Flat multi-hole tubes (A) made of aluminum or the same alloy are often used as tube materials for serpentine heat exchangers for car air conditioners and the like. The flat multi-hole pipe (A)
As shown in Fig. 5, it is manufactured as a hollow extruded material (10) having a large number of parallel hollow parts (11) inside, but in recent years, with the aim of improving heat exchange efficiency, There is a strong demand for larger sizes and more holes, and along with these demands, higher precision is also required in the design and manufacture of extrusion dies.

A die for manufacturing a flat multi-hole tube consists of a combination of a female mold that defines the outer shape of a hollow extruded material (10) and a female mold that has a large number of molding convex parts that mold a hollow part (11), Conventionally, electrical discharge machining technology has generally been employed to manufacture these die molds.

In manufacturing such a die, the die hole can be formed with precision relatively easily by machining the female die using electric discharge machining technology using wire cutting. However, as shown in FIG. 4, it is difficult to manufacture a male mold (8) having a large number of molded convex portions (9) for hollow parts by electric discharge machining using simple wire cutting. Therefore, conventionally the third
As shown in the figure, a porous electrode material (6) is prepared in advance in which a large number of holes (7) corresponding to the molded convex portions (9) are arranged in a row, and electrical discharge machining is performed using the electrode material (6). By doing this, the bearing part (9a), in which the precision of the tip of the molded convex part (9) also plays an important role, is molded, and then the part that goes from the neck to the base of the molded convex part (9) is molded. Manufactured by wire cut electrical discharge machining.

Problems to be Solved by the Invention However, in the conventional manufacturing method of the male die mentioned above, it is difficult to manufacture the electrode material (6) for the molding process.
The problem was that it was expensive. That is, the electrode material (
In 6), a large number of holes (7) are also drilled and formed by electrical discharge machining using wire cutting, but since the holes are each independent and must be drilled in large numbers, it is not suitable for electrical discharge machining. Connect wires as electrodes to individual holes (7)
It is necessary to pass the wires through each hole separately, connect them one after another, and perform electrical discharge machining for drilling.Not only is it difficult to automatically connect the wires, but it is also difficult to accurately position each hole. Couldn't get anything.

In particular, the difficulty of the above-mentioned wire connection work and positioning work significantly reduces the production efficiency of the porous electrode material (6).
Not only does this increase the production cost, but also the electrode material (6)
Insufficient manufacturing precision makes it difficult to make the flat multi-hole tube (A) thinner, and for example, it is difficult to manufacture dies for multi-hole tubes with a wall thickness of 0.5M or less. The reality is that it was.

Based on the background of the prior art as described above, this invention improves the manufacturing technology of electrode materials for male die electrical discharge machining, thereby making it possible to manufacture them simply, efficiently, and with high precision. The purpose of the present invention is to enable highly accurate and highly efficient manufacturing of extrusion dies for thin-walled flat multi-hole tubes.

Means for Solving the Problems In the present invention, a male electrode material for electric discharge machining is divided into two halves in advance, and a large number of holes are cut into two halves on one side thereof using a wire cutting technique. The main idea is to perform continuous machining in a single-stroke manner as a divided hole, and then perform electric discharge machining on an important part of the molding convex part of the male die using a pair of the divided electrode materials.

That is, in the present invention, a porous electrode material is prepared in which a large number of holes corresponding to the bearing portions of a male die are arranged in a row, and the electrode material is used to perform electrical discharge machining to form at least one of the many molded convex portions of the male die. In a method for manufacturing an extrusion die for a flat multi-hole tube in which a bearing portion at the tip is formed, the multi-hole electrode material is divided into two parts, and the porous electrode material is divided into two parts. A flat polygon characterized in that a row of half-split split holes are formed on one side edge by wire-cut electric discharge machining, and then a male die material is subjected to electric discharge machining using a pair of the divided electrode materials. The gist of this paper is a method of manufacturing an extrusion die for hole pipes.

Example The invention will be further explained below based on illustrated embodiments.

As mentioned above, a flat multi-hole tube (A
The male die (8) of the extrusion molding die of
) A large number of molded convex portions (
9). In manufacturing the male die (8), the molding process of the molding convex part (9) is carried out at least in the region including the bearing part (9a) at the tip thereof, as shown in FIG. This is carried out by electric discharge machining using a porous electrode material (1) of a predetermined thickness having a large number of holes (2) corresponding to 9a).

In the present invention, the electrode material (1) is manufactured as follows.

That is, the electrode material (1) is placed 2 times from the center of the row of holes (2).
Split electrode material (la) (l) separated at the splitting position
b), and a large number of dividing holes (2a) (2b) are formed in opposing shapes on one side edge of each by wire cut electrical discharge machining. In this case, the forming process of the split holes (2a) and (2b) is such that both split holes are open to the side surfaces of the split electrode material (la) (lb), so they cannot be used as electrodes for electrical discharge machining. It is possible to process continuously in a single stroke using a single wire, and wire cuts can be made for each hole.

The split electrode material (la) (lb) can be efficiently formed without requiring the trouble of forming wires.

Therefore, 1 of this divided electrode material (la) (lb)
Using the pair, electric discharge machining is performed on the main portion of the molding convex portion (9) of the male die (8), including at least the bearing portion (9a). In this case, the divided electrode material (la) (lb
) may be used individually and electrical discharge machining may be carried out in a divided manner, but it is preferable to place the electrode materials (la) and (lb) on both sides facing each other in advance and bond them together with adhesive. It is desirable that after the electrodes are integrated into an integrated electrode assembly (1), the molding convex portion (9) of the male die (8) is formed by electrical discharge machining.

Electric discharge machining using the electrode material (1) is performed on the bearing part (9a).
shall be performed on the tip of the molded convex portion (9) containing the
Next, the molded convex part (
The outer peripheral surface from the head (9b) to the base (9c) of 9) is processed to complete the male die (8).

The electrode material (1) is made of copper, brass, an alloy of tungsten and copper, carbon, etc., and its thickness is generally about twice the length of the bearing part (9a). things are used.

Effects of the Invention According to the present invention, in the manufacture of a die for extruding flat multi-hole tubes, particularly a male die, the electrode material used for the processing is divided into two parts, and each of the divided electrode materials has a dies on one side. After the open split holes are formed by wire cutting, the pair is used to perform electrical discharge machining of the tip of the molding convex part, which is the main part of the male die, at least including the bearing part. There is no need to repeat the wire cut connection many times, unlike when producing a single electrode material with a hole through multiple perforation processes using wire cutting, making the production of electrode materials more convenient and efficient. Therefore, it can be done inexpensively. Furthermore, since the electrode material is manufactured as a split type as described above, the molding precision of the hole can be increased to 12 degrees, which in turn improves the manufacturing precision of the male die, which is difficult to do with conventional methods. It is possible to obtain effects such as making it possible to manufacture a high-precision die that can be used without any problem in manufacturing thin-walled multi-hole tubes such as those described above.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the manufacturing state of the split electrode material for electric discharge machining used in the present invention, Fig. 2 is a plan view showing the state of combination when using the split electrode material, and Fig. 3 is a perspective view showing the manufacturing state of the split electrode material for electrical discharge machining used in the present invention. FIG. 4 is a plan view of the electrode material for electric discharge machining used, FIG. 4 is a perspective view of an example of a male die manufactured according to the present invention, and FIG. 5 is a perspective view of an example of a flat multi-hole tube. (1)... Electrode material, (la) (lb)...
Split electrode material, (2)...hole, (2a) (2b
)...Divided hole part, (8)...Male die, (9)
...Molding convex part, (9a)...Bearing part, (A)
...Flat multi-hole pipe. Patent applicant: Showa Aluminum Co., Ltd.

Claims (2)

[Claims] (1) A porous electrode material is prepared in which a large number of holes corresponding to the bearing parts of the male die are arranged in a row, and the electrode material is used to perform electrical discharge machining to form a bearing at least at the tip of the large number of molded convex parts of the male die. In the method of manufacturing an extrusion die for a flat multi-hole tube, the porous electrode material is divided into two parts, and one side edge of the multi-hole electrode material is divided into two parts. Extrusion for flat multi-hole tubes, characterized in that a line of half-split split holes is formed in each part by wire-cut electric discharge machining, and then a male die material is subjected to electric discharge machining using a pair of the divided electrode materials. How to make dice. (2) A pair of split electrode materials are bonded together in advance using an adhesive, and then the male die material is subjected to simultaneous electrical discharge machining using this combination of porous electrode materials.
A method for producing an extrusion die for flat multi-hole pipes as described in Section 1.