JPH09111372A - Copper alloy for commutator for motor used for fuel transport pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a copper alloy for motor commutator, excellent in wear resistance as well as corrosion resistance to alcohol fuel, by specifying a composition consisting of Si, Sn, Fe, P, and Cu and forming a structure in which Fe-based precipitates are dispersed. SOLUTION: This alloy is a copper alloy having a composition consisting of, by weight, 0.05-2.0% Si or 0.5-4.0% Sn, 0.1-2.8% Fe, <=0.5% P, and the balance Cu with inevitable impurities and also having a structure in which Fe-based precipitates are dispersed. Fe and P in this alloy are precipitated as precipitates by means of aging treatment in the course of working for alloy stock. By using this copper alloy for commutator for motor used for fuel transport pump, the durability of the motor can be improved even in alcohol.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a commutator material for a DC motor used in a fuel feed pump.

[0002]

2. Description of the Related Art A fuel feed pump is composed of a pump portion and a motor portion, and since the motor portion uses a direct current motor, it has a commutator.

A copper alloy containing silver has been conventionally used as a commutator material. This is to prevent the material from being softened by the heat at that time because it is resin-molded when assembled as a commutator.

By the way, conventionally, gasoline or light oil has been used as a fuel for automobiles, but in recent years, there is a call for prevention of environmental pollution on a global scale.

[0005]

When alcohol is used as the fuel, the corrosiveness of alcohol is higher than that of the conventional fuel. Therefore, the commutator is corroded in the conventional silver-containing copper alloy, and the motor using this alloy is It has the drawback of low durability.

An object of the present invention is to provide a commutator material which does not corrode even when used in alcohol fuel and can improve the durability of the motor to the same level as when used in gasoline. is there.

[0007]

The gist of the present invention is Cu
By adding Si (silicon) or Sn (tin) to (copper) to improve the corrosion resistance to alcohol,
The point is to improve wear resistance due to precipitates by adding (iron) and P (phosphorus).

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Since the alloy material according to the present invention is a Cu-Si series or Cu-Sn series alloy having high corrosion resistance in alcohol, it is used as a commutator of a fuel feed pump for alcohol fuel. When used, the commutator is not corroded by alcohol.

Further, it is known that a metal material in which precipitates are uniformly dispersed has a high wear resistance. However, Fe and P in the alloy according to the present invention are affected by aging treatment during processing of the alloy material. Since it precipitates, the wear resistance of the alloy material is improved, and as a result, the properties of high corrosion resistance and wear resistance in alcohol fuel are obtained.

For each additive element of the alloy material according to the present invention, Si is 0.05% by weight (hereinafter, simply expressed as%).
% Or less, the corrosion resistance is not improved so much, and if it is 2% or more, the ductility of the material decreases and the processing becomes difficult. In the case of Sn, if it is 0.5% or less, the corrosion resistance is not improved, and if it is 4% or more, the electrical conductivity of the material decreases and the processing becomes difficult. If Fe is 0.1% or less, the wear resistance due to precipitates is not improved, and if it is 2.8% or more, the conductivity decreases.

Further, P forms a compound with Fe to form a precipitate and has the effect of improving wear resistance, but 0.5%
Above, there is a problem that the conductivity is lowered.

[0012]

An embodiment of the present invention will be described.

A copper alloy having the composition shown in Table 1 was melted and cast by a conventional method, and the obtained ingot was hot-rolled to a plate thickness of 10 mm and water-cooled. Cold rolling it to a thickness of 2.5 mm, 45
After heat treatment at 0 ° C., it was cold rolled to a thickness of 2.0 mm.
A disc-shaped sample having a diameter of 40 mm was cut out from each of the obtained materials and subjected to a life test.

The life test is carried out by the motor 1 as shown in FIG.
The sample 3 is installed on the tip of the rotary shaft of the above, and the carbon brush 2 is installed so that the tip is pressed against the sample 3, and this is immersed in the test fuel 4 cooled by the cooling water 5 together with the device, 3 was rotated at 4000 rpm, and a direct current of 10 A was passed from the carbon brush 2.

1% water, 84% alcohol, 1 gasoline
The above test was continuously performed for 30 times in test fuel 4 consisting of 5%.
The test was taken out for 0 hours, the sample after the test was taken out, and the amount of wear was determined from the weight change before and after the test and the area of the worn part. The results are also shown in Table 1.

[0016]

[Table 1]

From the results shown in Table 1, it can be seen that the alloy material according to the present invention shows a wear amount of about one-third or less that of the conventional material, and has excellent durability in alcohol fuel.

It is also understood that the wear of the portion of the sample other than the brush contact portion is improved.

[0019]

As is apparent from the above, the alloy material according to the present invention has excellent corrosion resistance and wear resistance even when used in alcohol fuel, and the durability of a motor using the alloy material as a commutator is improved by gasoline. There is an industrially remarkable effect that it can be made equivalent to the case of being used inside.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a wear test apparatus.

[Explanation of symbols]

 1 Motor 2 Carbon brush 3 Sample 4 Test fuel 5 Cooling water

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hajime Sasaki 3550 Kidayomachi, Tsuchiura City, Ibaraki Prefecture Hitachi Cable Ltd. System Materials Research Center

Claims (1)

[Claims] 1. In weight percent, 0.05 to 2.0% Si or 0.5 to 4.0% Sn and 0.1 to 2.8% Fe.
A motor used in a fuel delivery pump, characterized by containing 0.5% or less of P, the balance being Cu and inevitable impurities, and having a structure in which Fe-based precipitates are dispersed. Copper alloy for commutator.