JPS58104138A - 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- Mn alloy due to oxidation and maintaining the lubricity by adding prescribed percentages of Mn and one or more among Pt, Ru and Pd to Ag. CONSTITUTION:This sliding contact material is made of an Ag-Mn alloy obtd. by adding 1-10wt% Mn 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 remarkably enhanced. An increase in the contact resistance of the Ag-Mn 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.

A with excellent lubricity as a sliding contact material
g-Mn alloy has been used, but the sliding contact material of Ag-Mn alloy has the disadvantage that it is easily oxidized and the contact resistance is high and unstable. When a contact piece on the outer periphery of the commutator is manufactured and used, the contact resistance with the abrasive contact changes, and if the rotation speed of the commutator is high, the commutator becomes unstable.

The present invention has been made to eliminate such drawbacks.5
It is an object of the present invention to provide a sliding contact material f which suppresses the increase in contact resistance caused by oxidation of the Ag-Mn alloy, improves wear resistance while maintaining lubricity, and has a low and stable contact resistance.

The sliding contact material of the present invention is made by adding at least one of Mnl~]0- and Pt, Ru, and Pd in total to Ag.

In the sliding contact material of the present invention, 1' to
pt in addition to adding Mn of 10'N10.

By adding at least one of Ru and Pd in a total of 0.5 to 2, the contact piece on the outer periphery of the commutator made of a material to which these elements are added has a contact resistance due to oxidation in the Ag--Mn alloy. This is because when the increase in Kg is suppressed, the lubricity of the Ag-Mn alloy is maintained, and the wear resistance is improved, the contact resistance of Kg becomes low and stable.
The increase in contact resistance due to oxidation in n-alloy is not suppressed,
45MnOx is generated, resulting in high contact resistance and instability.If it exceeds 2%, the properties such as lubricity of the Ag--Mn alloy are lost and the wear resistance decreases, so in the end, the contact resistance becomes unstable.
Addition of 5-2″W10 is required.

In the evening, 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.

Using the sliding contact material according to the embodiment of the present invention and the conventional sliding contact material having the compositions shown in IIIK of the table below, a commutator l of a small motor with a diameter of 6 Iu and a length of 9 m is used as shown in the drawing. A contact piece 1at with a thickness of 0.2 wx is formed on the outer circumference of the contact piece 1at.A contact piece 1at with a diameter of 0.25 m made of Au-Ag-Cu-Pt is formed on the upper and lower sides of the outer peripheral surface of this contact piece 1m.
, a brush contact 3 having three brush wires 2 with a length of 10 m
A rotation test was performed on the commutator L under the test conditions described below, with the contact pieces facing each other in sliding contact, and the wear amount of the contact piece 1m and the variation in the rotation speed of the commutator L were measured. The results shown in the right column were obtained.

Test conditions Voltage: 12V Current: DC59mA Commutator rotation speed: 280Orpm Commutator rotation time = 500 hours * Contact crab of S contact 5g/3 pieces As is clear from the table above, the conventional contact piece The amount of consumption is 5
〜6μ, but the amount of wear of the contact piece in the example was 3μ.
It can be seen that the wear resistance is significantly reduced at ~4μ, indicating excellent abrasion resistance. Furthermore, the variation in rotational speed of the conventional commutator with In pieces is t! It can be seen that the variation in the rotational speed of the commutator having the contact piece of the example was significantly reduced within 2 to 5 degrees, whereas Fi was 7 to 1 degrees. This is simply because the contact piece of the example has a low and stable contact resistance due to suppressed increase in contact resistance due to oxidation of the Ag--Mn alloy.

As detailed above, the sliding contact material of the present invention is Ag-M
Since the increase in contact resistance due to oxidation of the n-alloy is suppressed and lubricity is maintained, the wear resistance of the commutator contact pieces of small motors made with andfl is significantly improved. In addition, the increase in contact resistance due to oxidation of the A g -M n alloy is suppressed, and the contact resistance is low and stable.
It has excellent effects such as greatly reducing variations in the rotation speed of the commutator of small motors.

[Brief explanation of the drawing]

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

Claims (1)

[Claims] In Ag, M n l = 10′! 10 and Pi, R
A sliding contact material comprising a total of 0.5 to 2W10 of at least one of U and Pd.