JPS6287620A - Manufacture of rotor for rotary piston engine - Google Patents

Abstract

PURPOSE:To aim at the promotion of lightweightiness in a rotor as well as to improve a degree of joining strength or coherence, by forming a frame-form body with an expanded body of nickel, and filling up an aluminum alloy in a lot of holes in the said expanded body. CONSTITUTION:A frame-form body having an apex seal groove 1 and a side seal groove part 2 is formed with an expanded body of nickel. This frame-form body is subjected to internal chill with an aluminum alloy by means of high pressure casting whereby an intermediated product for a rotor is formed. At this time, molten metal of the aluminum alloy is filled up in a lot of holes in this frame-form body. Thus, lightweightiness in the rotor is well promoted, while joining strength or coherence between the nicket expanded body and the aluminum alloy is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a rotor for a rotary piston engine, particularly a rotor made of an aluminum alloy.

(Prior art) In a rotary piston engine, an approximately triangular rotor that rotates planetarily within a casing having a cocoon-shaped inner peripheral surface has an apex seal formed along each vertex and attached with an apex seal. A seal groove, a corner seal groove formed at each apex corner on both sides to which a corner seal is attached, and a side seal groove formed at a peripheral portion on both sides to which a side seal is attached are provided. However, the inner surface of these grooves is prone to wear due to large forces acting through each seal when the rotor rotates, or due to welding with the seals, so the surrounding areas of the matching grooves have excellent wear resistance. I need to be there. In particular, the aluminum alloy rotor used to reduce the weight of the rotor and increase its rotation speed is subject to severe wear as described above, and to prevent this, the wear resistance of the surrounding areas of the matching grooves has to be improved. The question is how to secure it.

Therefore, as shown in Japanese Utility Model Application Publication No. 49-42303, for example, each top side portion of the rotor where the apex seal groove is formed, and the peripheral portions of both side surfaces where the side seal groove and corner seal groove are formed. It has been proposed to form an integral frame made of cast iron and to manufacture a rotor made of aluminum alloy by casting this integral frame with aluminum alloy. According to this, since the apex seal groove, corner seal groove, and side seal groove are formed in the cast iron integral frame, the required wear resistance is ensured and wear of the multiple grooves is prevented. Become.

However, the one disclosed in the above publication is an integral frame (
Because the multi-groove formation part is made of heavy cast iron, it is difficult to reduce the weight of the rotor, and when the rotor rotates, large stress is applied to the joint between the cast iron frame and the aluminum alloy. Because of this, or because the thermal expansion coefficients of the two are different, the adhesion of the bonded portion may decrease and peeling may occur at the bonded portion.

(Object of the Invention) The present invention deals with the above-mentioned situation regarding the rotor made of aluminum alloy in a rotary piston engine, and it is an object of the present invention to solve the above-mentioned situation regarding the rotor made of aluminum alloy in a rotary piston engine. In the case where a rotor is manufactured by forming an integral frame-like frame that constitutes the periphery of both side surfaces where the grooves are formed, and casting this frame-like frame with an aluminum alloy, the above-mentioned frame-like The frame and aluminum alloy are in good condition! To obtain an aluminum alloy rotor which does not peel off at a joint between the two when worn, has sufficient wear resistance around multiple grooves to prevent wear of the grooves, and is sufficiently lightweight. With the goal.

(Structure of the Invention) In order to achieve the above object, a method for manufacturing a rotor for a rotary piston engine according to the present invention is characterized by having the following structure.

That is, a frame having an apex seal groove and a side seal groove is formed of nickel foam, and then this frame is formed of aluminum alloy using a high pressure casting method such as die casting or molten metal forging. The intermediate product of the rotor is formed by casting. Then, a predetermined heat treatment is performed on this intermediate product.

According to this method, when the frame-shaped frame made of the nickel foam is wrapped in aluminum alloy by high-pressure casting, the molten metal of the aluminum alloy fills a large number of holes in the frame-shaped frame. be done. In addition, by subjecting the intermediate product of the rotor cast-molded in this way to a heat treatment such as a continuous treatment of solution treatment called T6 treatment and artificial age hardening treatment, the aluminum alloy is hardened. Instead, a high hardness alloy layer (intermetallic compound) consisting of nickel and aluminum is formed at the interface between the nickel foam and the aluminum alloy, especially around the aluminum alloy filling the pores of the foam.
is formed. In this state, if an apex seal groove, a side seal groove, and a corner seal groove are respectively formed in the apex seal groove and the side seal groove of the frame-like frame, the high hardness alloy layer is formed on the inner surface of the multi-groove. will appear.

(Effects of the Invention) As described above, according to the method for manufacturing a rotor for a rotary piston engine according to the present invention, the frame-like body having the apex seal groove and the side seal groove is formed of a nickel foam, In addition, since the aluminum alloy is filled into the numerous pores in the foam, the weight of the rotor is reduced compared to when a cast iron frame is used, and the bonding strength between the nickel foam and the aluminum alloy is improved. No way W! The adhesion is improved and problems such as peeling at the joint between the two can be avoided. Furthermore, by applying heat treatment as the final step, a high hardness alloy layer of nickel and aluminum is formed on the interface between the nickel foam and the aluminum alloy, and the apex seal groove, corner seal groove and side seal groove are formed. When processed, this high hardness alloy layer appears on the inner surface of the multi-groove,
This ensures wear resistance around the groove and prevents wear on the inner surface of the groove. In this way, according to the invention:
An aluminum alloy rotor is realized in which there is no peeling between the frame and the aluminum alloy in which the frame is cast, the wear resistance of each seal groove is ensured, and the weight is sufficiently reduced.

(Example) Hereinafter, an example of a method for manufacturing a rotor in a rotary piston engine according to the present invention will be described.

First, as a first step, as shown in FIGS. 1 to 3, each top side of the rotor is configured to form an apex seal groove.
Apex seal groove forming members 1...1 (corner seal grooves are formed on both end faces of these forming members 1...10) and side seals forming peripheral parts on both side surfaces of the rotor. Six side seal groove forming members 2...2 in which grooves are formed are each made of nickel foam, and these members 1...1, 2...2 are connected to form a frame. A shaped frame body 3 is produced. In that case,
For each of the above members 1...1, 2...2 (nickel foam), for example, granular urethane resin is coated with graphite, and this is filled into a mold of a predetermined shape, and then nickel plated. It is obtained by applying, eroding, and burning out the urethane resin, and by bonding each member 1...1.2...2 obtained in this way with, for example, wax etc. The frame-like frame body 3 is produced.

Next, as a second step, the frame body 3 produced as described above is set in a mold having a predetermined shape,
After that, an aluminum alloy (composition example, s;
:1a%, Cu:3%, Mo:0.4%, Ni:0
．． 18%, Sb: 0°16%, Mn: 0.14%, F
e: Q, 14%, Ti: 0.09%, remainder: Ai)
By casting the molten metal and casting the frame 3 with the alloy, an intermediate rotor product 4 as shown in FIG. 4 is obtained.

Here, by casting the frame body 3 with aluminum alloy by high-pressure casting, a large number of pores in the frame body 3 are filled with molten aluminum alloy. Then, each top side portion 4a of the intermediate product 4...
・4a is an apex seal groove forming member 1'...1 whose holes are filled with aluminum alloy as described above.
', and the peripheral parts 4b...4b on both sides of the rotor 4 are formed by side seal groove forming members 2'...2 whose holes are similarly filled with aluminum alloy.
', and the other part 5 is made of aluminum alloy.

Furthermore, the rotor intermediate product 4 produced in this way was subjected to a solution treatment (approximately 20°C x 4 hours) and an artificial age hardening treatment (approximately 70°C x 8 hours) as a third step. A continuous heat treatment called T6 treatment is performed. By performing such heat treatment, the aluminum alloy portion 5 in the intermediate product 4 is hardened, and as shown in FIG. 5, the apex seal groove forming member 1'...
1' (same for side seal groove forming member 2'...2')
In, nickel foam 1a and aluminum alloy 1
b...1b, a high hardness alloy layer (intermetallic compound) 6...6 made of nickel and aluminum is formed. After being subjected to heat treatment as described above, as shown in FIG.
...Apex seal groove 7 along the top of 1'...7
However, corner seals 1ll8...8 are formed on both end surfaces of the members 1'...1', and side seal grooves 9 are formed on the outer surfaces of the side seal groove forming members 2'...2'. . . 9 are respectively formed, and predetermined machining is performed to obtain a rotor body 10 made of aluminum alloy as a final product. In that case, the above 8 grooves 7
...7, 8...8, 9...9 has a high hardness alloy layer 6... made of the above-mentioned nickel and aluminum on the inner surface.
6 will appear.

In the thus obtained rotor body 10, the frame body 3 shown in FIGS. 1 to 3 is formed of a nickel foam having a large number of holes, so that when a cast iron frame is used, In addition to being lighter in weight in comparison, the numerous holes in the frame-like frame 3 are filled with aluminum alloy, which improves the bonding strength or adhesion between the frame 3 and the aluminum alloy. This prevents the two from peeling off. Furthermore, since a high hardness alloy layer appears on the inner surfaces of the apex seal grooves 7...7, corner seal grooves 8...8, and side seal grooves 9...9, these grooves 7...
- The wear resistance around 7, 8...8, 9...9 will be improved. Further, since nickel, which is the material of the frame-shaped frame 3, has a smaller coefficient of thermal expansion than aluminum alloy, the frame 3 suppresses the thermal expansion of the entire rotor.

In the above embodiment, each seal groove 7...7, 8...8.9 is formed after heat treatment is applied to the rotor intermediate product 4.
. . 9 is formed, but on the contrary, heat treatment may be performed after forming each seal groove 7 . . . 7, 8 . . . 8, 9 .

[Brief explanation of drawings]

The drawings show an embodiment of the method of the present invention; FIG. 1 is a perspective view of a frame used in this embodiment, FIG. 2 is a front view of the frame, and FIG. 3 is a front view of the frame. 4 is a perspective view showing an intermediate product of the rotor whose frame body is cast in aluminum alloy, and FIG. 5 is an enlarged view showing the outline of the metal structure after heat treatment of the intermediate product. FIG. 6 is a perspective view of a rotor body in which multiple grooves are formed. 1.1'...Apex seal groove forming member, 2゜2'
... Side seal groove forming member, 3... Frame-shaped frame body, 4... Intermediate product, 6... Nickel-aluminum alloy layer.

Claims (1)

[Claims] (1) A method for manufacturing an aluminum alloy rotor for a rotary piston engine, in which a frame-like frame having an apex seal groove and a side seal groove is formed from nickel foam, and then this frame-like frame is ,
An intermediate product of the rotor is formed by casting an aluminum alloy using a high-pressure casting method so that a large number of holes in the frame are filled with molten metal, and then this intermediate product is heat-treated. A method for manufacturing a rotor for a rotary piston engine, characterized in that a nickel-aluminum alloy layer is formed on the interface between the nickel foam and the aluminum alloy.