JP2897385B2 - Rotor shape extrusion method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a rotor shape extrusion method for manufacturing a rotor material such as a vane rotary compressor for a car air conditioner from an aluminum alloy.

[Conventional technology]

Conventionally, a rotor in a rotary compressor or the like is manufactured by machining, forging, or sintering an iron ore-based material. A rotor made of an iron ore-based material has excellent strength and wear resistance, but is inferior in terms of weight reduction. Reducing the weight of the rotor not only improves performance, but also contributes to low fuel consumption and energy saving, for example, in a compressor air conditioner rotor.

For this reason, the rotor was made hollow by using a sintering method using an iron ore-based material to reduce the weight, but the weight was limited because the material was an iron-based material. Therefore, a light aluminum alloy rotor has been studied.
In the prior art, the shape of the slit portion (vane groove portion) of the rotor is formed by machining in a steel rotor or in powder molding in an iron-based sintered material rotor. In addition, in the case of an aluminum stretched material rotor, a slit shape was machined from a round bar by machining to be prototyped.

[Problems to be solved by the invention]

By the way, the ingot material aluminum alloy such as a normal sash is formed by an extrusion method. However, even in the case of the aluminum alloy rotor which is desired for weight reduction as described above, the vane groove is particularly required in view of the manufacturing cost. It is desired that a rotor having a shaft and a shaft hole be formed by extrusion.

In extrusion of aluminum alloy such as ordinary sash,
The extruded material comes out of the extruder, chucks at a place where it is easy to chuck with a puller (at least 2 m from the die exit), pulls and pushes out, discards the defective part at the top, re-dissolves and discards the discarded part Billet. Since the cut-out portion is about 2.5 m for the entire length of extrusion (about 50 m), the defective rate is as small as 5%, and the material used for the sash and the like has a low recycling cost, so that the production cost is not reduced. .

On the other hand, the aluminum alloy used for the rotor is required to have characteristics such as strength and wear resistance, a low coefficient of thermal expansion, and characteristics such as not causing seizure due to sliding.
An alloy containing transition metals such as Sl, Fe, and Ni added to Al is used.However, when the amount of Si increases, the extrusion process deteriorates and cracks occur immediately, and the plastic fluidity also deteriorates and the initial extrusion pressure increases significantly. . Also, an increase in the transition metal deteriorates the extrudability. Therefore, when an aluminum alloy having both strength and abrasion resistance is used as an extruded material and manufactured by an extrusion method into a complicated shape such as a rotor having vane grooves, the die strength is insufficient.

From this point of view, the formation of a slit shape by the extrusion method has not yet been studied, and the present inventors have applied an easily extrudable aluminum alloy to the front of the billet of the aluminum alloy for the rotor to reduce the initial pressure. After hitting as a board and extruding,
A method for removing the patch plate from the extruded material obtained
It is only proposed in the specification of 62-159756.

Although the initial pressure can be reduced by the method of the prior application, if the above-described extrusion method such as a sash is applied as it is, it is still unsatisfactory in terms of accuracy and yield.

Furthermore, unlike a sash, etc., the length of the extruded material is at most about 5 m in the case of a rotor, and when pulled with a puller,
Since 2.5 m is truncated, the rejection rate reaches 50%, and the expensive alloy is used as the material. Recycling of the alloy is very costly, resulting in a very wasteful and costly method.

In view of the above situation, the present invention provides a method of extruding an aluminum alloy to obtain a rotor shape, which has a high production yield, further improves the dimensional accuracy of the slit, and accurately determines the perpendicularity of the slit after cutting to the cut surface. The object of the present invention is to provide a rotor-shaped extrusion method that allows even this.

[Means for solving the problem]

An object of the present invention described above is to provide a method of indirectly extruding an aluminum alloy into a rotor shape having a slit as an extruded material. This is achieved by a rotor-shaped extrusion method characterized by pulling.

The extruded material of the present invention is particularly preferably a rapidly solidified aluminum alloy powder having a cooling rate of 100 ° C./sec or more or a particle size of 350 μm or less formed into a billet by CIP molding.

Hereinafter, the present invention will be described with reference to the drawings. FIGS. 1A and 1B show a specific example of the present invention. In an indirect extrusion method, an extruded material 2 immediately after leaving a die is chucked. [FIG. 1 (A)] shows a configuration in which pulling is performed by a puller [FIG. 1 (B)]. The billet 5 is set in the press container 8 and extruded with the press stem 6, but the die 3
The extruded material 2 immediately after exiting from the die is chucked by the chuck device 1 and pulled in the die stem 7 by the puller 4 with a constant tension while synchronizing with the extrusion speed.

In order to chuck the extruded material in the die stem immediately after the die exit, it is actually difficult to select and design the material for the chuck and puller in a narrow space and at a high temperature of around 400 ° C. The present inventors have selected a suitable material, detected that the extruded material came out of the die, and actuated the chuck portion thereby to realize the method of the present invention.

2 (A) and 2 (B) are perspective views showing a rotor material obtained by cutting the extruded material 2 obtained according to the present invention. 9 is a slit (vane groove), 10 is an inner diameter hole, 11 and 11 '
Indicates a rotor cross section.

[Action]

The method of the present invention, in which the extruded material immediately after passing through the die is chucked in the die stem and pulled with a puller to improve dimensional accuracy, is a method of chucking and pulling at a position of about 2 m after passing through the die, which is performed by a normal extrusion method. As a result, the yield is improved, and, naturally, the amount of cutting off at the head for recycling is reduced.

In ordinary aluminum alloys such as A6063, there are many cases where there is no problem in terms of cost without increasing the head yield due to emphasis on productivity, but when using expensive alloys, for example, rapidly solidified aluminum alloy powder, etc. Recycling requires an expensive atomizing process. Therefore, the method of the present invention having a small head truncation as in the present invention is very effective in such an expensive aluminum alloy extrusion method.

Further, when the extrusion ratio is low as in the rotor, the extruded material has a short overall length, so that extruding without using the method of the present invention, that is, extruding without a puller, cannot obtain a portion with good dimensional accuracy.

As shown in FIGS. 2 (A) and 2 (B), the rotor has a slit (vane groove) 9 that is not oriented in the center direction. Therefore, according to the conventional method of chucking after the extruded material comes out of the extruder. It is easily extruded while twisting in the die stem, and bends under its own weight due to gravity. As described above, since the rotor is an aluminum alloy with a high Si or Fe content due to the required characteristics of the parts, it is impossible to correct bending and twisting with a stretcher like a sash of molten material after extrusion. is there. On the other hand, according to the present invention, since chucking is performed immediately after the die, twisting and bending can be prevented.

When the puller chuck is attached immediately after the die, the moving speed of the puller chuck decreases, but since the entire length of the extruded material is short, this does not reduce the productivity.

The method of the present invention is effective for both direct extrusion and indirect extrusion. The indirect extrusion method has advantages over the direct extrusion method in that the metal flow is uniform and the speed of the extrusion itself can be increased. On the other hand, due to the structure of the equipment, the die stem must receive all of the pushing force, so that the stem pressure is required according to the pressing ability, so the diameter of the hollow part through which the extruded material passes is limited, but for the rotor Is enough for

The method of the present invention is not only effective for round shapes such as rotors, but also for round bars, and can be carried out for extrusion of 6 holes or 8 holes like vanes. .

〔Example〕

Example 1 and Comparative Example 1 Al-17% by weight Si-5% by weight Fe-3% by weight Cu-1% by weight
A CIP compact billet and a A390 continuous cast billet of a rapidly solidified alloy powder (350 μm or less) having a Mg composition were prepared. Each has a diameter of 170 mmφ and a length of 550 mm. Each of the five slits (width: 60mmφ) as shown in Fig. 2 (B)
(3 mm, length 18 mm) by the method of the present invention. The billet heating temperature is 460 ° C. (Example 1).

For comparison, the same CIP compact billet and continuous casting billet used in the above example were extruded under the same conditions except that they were extruded in a free state without chucking (Comparative Example 1).

The product 1 of the present invention according to Example 1 had a good perpendicularity of the inner surface of the slit to the cut surface of 0.08 or less.
The comparative product 1 had 0.30 or more spots. Further, in the product 1 of the present invention, the bending was 3 mm or less in total length, but in the comparative product 1, it was as large as 40 mm.

Example 2 and Comparative Example 2,3 17% by weight Si-5% by weight Fe-3.5% by weight Cu-1% by weight Mg
-A powder compact (170 mmφ × 600 mml) having a balance of Al
Using a 500-ton indirect extruder, the shape of a vane groove (3.7 mmφ, 20 mml) in FIG.
C extruded. The extrusion temperature is 450 ° C., and the extruded material length after extrusion is about 3.5 m.

Condition A: According to the present invention, the extruded material is chucked in the die stem immediately after passing through the die and pulled by a puller (Example 2). Condition B: The extruder is free-extruded up to the counter frame, and the counter frame exits. Chuck (at a position of about 2.5 m) and pull with a puller (Comparative Example 2) Condition C: Free extrusion without puller (Comparative Example 3) After cutting each obtained extruded material to 50 mm in length with the same cutting machine B) The vane groove surface perpendicularity angle to the cut surface (end surface) (standard 0.1) and b) the vane groove position to the center (standard 6 ± 0.05) were measured. The results are shown in the table below.

As shown in the table, under the condition A (the present invention), the yield was 100%.
%, The condition B was good after the chuck and the yield was 25%, and the condition C was all poor and the yield was 0%. In order to obtain a high-yield extruded material having such a complicated shape with a high yield, the extruded material is not chucked and pulled by a puller from the place where the conventional counter frame is exited, but the die is exited as in the present invention. It is clear that chucking immediately afterwards and pulling with a puller is effective.

From the results of the above Examples and Comparative Examples, it can be seen that according to the method of the present invention, an aluminum alloy can be formed into a rotor shape without bending by an extrusion method with good squareness, high dimensional accuracy and good bending.

〔The invention's effect〕

As described above, according to the present invention, a product with good precision can be extruded with good yield, especially when the extrusion ratio is low,
That is, it is very effective when the extruded material has a short overall length or is used for an expensive raw material such as a rapidly solidified aluminum alloy powder or an aluminum alloy to which an expensive element is added.

[Brief description of the drawings]

1 (A) and 1 (B) are schematic sectional views showing an example of the indirect extrusion process of the present invention. In the figure, 1: chuck device, 2:
Extruded material, 3: die, 4: puller, 5: billet, 6: press stem, 7: die stem, 8: container. Fig. 2 (A)
(B) is a perspective view showing an example of a rotor material obtained by cutting the extruded material obtained by the present invention, wherein 9: slit portion (vane structure), 10: inner diameter hole, Material cross section,
Is shown.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B21C 23/14 B21C 23/10

Claims (2)

(57) [Claims] 1. A method for indirectly extruding an aluminum alloy into a rotor shape having slits as an extruded material,
A rotor-shaped extrusion method characterized by chucking the extruded material in a die stem immediately after the extruded material exits an extrusion die, and pulling a puller device together with the extrusion. 2. The extruded material is a rapidly solidified aluminum alloy powder having a cooling rate of 100 ° C./sec or more or a particle size of 350 μm or less formed by CIP molding into a billet. ).