JPS58104137A - Sliding contact material - Google Patents

Abstract

PURPOSE:To obtain a sliding contact material having an enhanced hardly dissipative property while inhibiting an increase in the contact resistance of an Ag- Cu alloy due to oxidation and maintaining the hardness and lubricity by adding prescribed percentages of Cu and one or more among Pt, Ru and Pd to Ag. CONSTITUTION:This sliding contact material is made of an Ag-Cu alloy obtd. by adding 1-10wt% Cu and 0.5-2wt% one or more among Pt, Ru and Pd to Ag. Since the contact material has said characteristics, the hardly dissipative property of the contact chip of the commutator of a small-sized motor formed with the contact material is enhanced. An increase in the contact resistance of the Ag-Cu alloy due to oxidation is inhibited to provide low and stable contact resistance, so variance in the number of revolutions of the commutator is considerably reduced.

Description

[Detailed description of the invention] The present invention relates to improvements in sliding contact materials.

Conventionally, Ag-Cu alloy with excellent hardness and lubricity has been used as one of the sliding contact materials, but Ag-Cu
Alloy sliding contact materials are easily oxidized, resulting in high contact resistance and instability. In this case, the contact resistance with the brush contact changed, and the rotation speed of the commutator varied widely and became unstable.

The present invention was made in order to eliminate such drawbacks, and suppresses the increase in contact resistance due to oxidation of the Ag-Cu alloy, improves wear resistance while maintaining hardness and lII resistance,
Moreover, it is an object of the present invention to provide a sliding contact material with low and stable contact resistance.

The sliding contact material of the present invention has a CLf of 1 to 10% in Ag.
and at least one piece of Pt, Ru, and Pd in a total of 0.5 to 2
It is made by adding W/.

In the sliding contact and material of the present invention, 1 to 1
In addition to adding 0 Wlo of Cu, Pt and Ru.

The reason for adding at least 0.5 to 2" of Pd in total is that contact pieces on the outer periphery of the commutator made of materials to which these elements are added will increase contact resistance due to oxidation in the Ag-Cu alloy. This is because the hardness and lubricity of the Ag-Cu alloy are maintained, the wear resistance is improved, and the contact resistance is low and stable.
-The increase in contact resistance due to oxidation in the Cu alloy is not suppressed, which means that CuO is generated, resulting in high contact resistance and instability7
However, if it exceeds 2'W10, it becomes difficult to process, and A
Since it impairs the lubricity properties of the g-Cu alloy and reduces wear resistance, it is necessary to add 0.5 to 2vj10.

Next, a contact piece for a commutator of a small motor made of a sliding contact material according to the present invention and a conventional sliding contact material will be explained.

As shown in the drawing, a small motor with a diameter of 6 m and a length of Au-Ag- Cu
- P t diameter 0.25 M, length 10
A rotation test was performed on the commutator 1 under the test conditions described below by sliding the brush contacts 3 containing the three brush wires 2 of m so as to face each other, and the wear amount of the contact piece 1a and the commutator 10 were When the variation in rotational speed was measured, the results shown on the right side of the table below were obtained.

Test conditions Voltage = 12 ■ Current: DC□QmA Commutator rotation speed: 2800 rpm11 As is clear from the table above, the wear t of the contact piece of the Vζ conventional example was 3.0 to 5.5μ, whereas It can be seen that the amount of wear of the contact piece of the example is reduced to 1.5 to 4.0μ, indicating that the contact piece of the example has excellent wear resistance. Further, the variation in the rotational speed of the commutator with the contact piece of the conventional example was 7.5 to 10 inches, whereas the variation of the rotational speed of the commutator with the contact piece of the embodiment If'! It can be seen that there is a significant decrease between 3 and 5 inches. This is because the contact piece of the embodiment is A g",', -Cu
This is because the increase in contact resistance due to oxidation in the alloy is suppressed and the contact resistance is low and stable.

As detailed above, the sliding contact material of the present invention is '1l-C
The increase in contact resistance due to oxidation of the u alloy is suppressed, and the hardness and
Since the lubricity is maintained, the wear resistance of the commutator contact pieces of small motors made using this method is improved. Further, since the increase in contact resistance due to oxidation of the Ag-Cu alloy is suppressed and the contact resistance is low and stable, there are excellent effects such as significantly reducing variations in the rotation speed of the commutator of a small motor.

[Brief explanation of the drawing]

The figure is a perspective view showing the state of contact a between the commutator and brush contacts of a small motor. 1...Commutator, 1a...Contact piece, 2.
...Brush wire, 3...Brush 1 creator Tanaka Kikinzoku Kogyo Co., Ltd.

Claims (1)

[Claims] In Ag, Cu1-to1'510 and Pi, Ru,
A sliding contact material containing a total of 0.5 to 2v10 of Pd and one type of Pd.