JPS5836197B2 - Manufacturing method of drive shaft for rotary compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a drive shaft for a rotary compressor, in which a shaft portion and a cam portion are manufactured separately, the cam portion is fixed at a predetermined position on the shaft portion, and a surface treatment is performed.

Conventionally, drive shafts used in rotary compressors such as air conditioners have been manufactured by integrally molding a cam part and a shaft part by casting or forging.

Therefore, in manufacturing, production efficiency is low considering the equipment.
Furthermore, in finishing machining, there is a large amount of machining allowance, which requires a lot of machining time, which ultimately leads to high costs.

It is known that the rotor disk and the rotating shaft are coupled by shrink fitting (see Japanese Utility Model Application Publication No. 51134210), but this is nothing more than ordinary shrink fitting.

Further, expansion due to carburizing and quenching and carbonitriding is usually treated as a deformation, and is treated as a problem for those skilled in the art.

The object of the present invention is to utilize this problem, which has conventionally been treated as a problem, to advantage.

That is, the shaft part made of steel and the cam part made of cast iron or steel are manufactured separately, and then the cam part is inserted and fixed in a predetermined position on the shaft part, and then carburized and quenched or carbonitrided. By doing this, the cam part and the shaft part are expanded slightly, which increases the degree of bonding between them, and at the same time forms a hardened layer on the surface, making it possible to manufacture a drive shaft with the same performance as conventional ones at an extremely low cost. An object of the present invention is to provide a method for manufacturing a drive shaft for a rotary compressor.

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

First, the shaft portion 1 is manufactured using a steel material having excellent wear resistance and impact resistance, for example, a steel material containing nickel, chromium, tungsten carbon, etc.

Next, a cam part 2 made of malleable cast iron or steel having excellent wear resistance and impact resistance similar to the shaft part 1 is manufactured, and the cam part 2 has a through hole 3 eccentric from the shaft center. take shape

Next, after fitting the through hole 3 of the cam part 2 into a predetermined position of the shaft part 1, the first product is manufactured by fixing by means such as welding, adhesive, or a key.

Finally, by carburizing and quenching or carbonitriding the primary product in which the shaft part 1 with the cam part 2 inserted therein is fixed via adhesive, the structure of the steel changes from austenite to martensitic structure. It expands and can increase the degree of connection between the cam part and the shaft part.

Due to this carburizing and quenching or carbonitriding, the structure of the steel changes from austenite to martensite, so we will submit the following experimental data regarding the slight expansion.

First, the drive shaft for the steel rotary compressor (outer diameter 18.2 ± 0.05 mvr x length 117.9 mvr
) and fixed it with adhesive.

Thereafter, carburizing and quenching was performed under the following conditions. [Carburizing furnace specifications] Operating humidity. Regular use 900°C, maximum 950'C heating method. Electric heating Heating power 8 2 Kw (Maximum capacity) Furnace dimensions.
600mmX12001rLrILX500mm Oil amount. , 600A' carburizing method. Dripping type gas carburizing [Carburizing conditions] 900'C 10'C I hours At this time, the outer diameter of the shaft was measured before and after carburizing and quenching.

, -0.2532 In this way, by carburizing and quenching, an average of 0.2 5 3 2 m
The outer diameter m is expanded, which makes the bond even stronger.

Furthermore, a hardened layer with corrosion resistance and wear resistance can be obtained on the surface, which is extremely effective.

When manufacturing the above-mentioned shaft part, the manufacturing process is to cut and machine a steel bar to form the shaft part material, and to form the cam part material by cutting a continuous bar with a cam shape. This is more advantageous in terms of shortening the shaft, and the cam part fitted and fixed to the shaft part has a special effect of further increasing the degree of connection by surface treatment, and at the same time, a hardened layer is formed on the surface.

Further, using a steel pipe material for the shaft portion is advantageous because it is not necessary to specially form an oil hole for forced oil supply.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a drive shaft for a rotary compressor obtained by the method of the present invention, FIG. 2A is a perspective view of a cam portion, and FIG. 2A is a perspective view of a shaft portion.

Claims (1)

[Claims] 1. A shaft made of steel and a cam made of cast iron or steel are manufactured separately, and then the primary product, in which the cam part is inserted and fixed in a predetermined position on the shaft, is carburized and quenched or carbonitrided. When the steel structure changes from austenite to martensitic structure, it expands.
A method for manufacturing a drive shaft for a rotary compressor, characterized in that a hardened layer is formed on the surface while increasing the degree of coupling between the cam part and the shaft part.