JPS60134750A - Slide contact piece adapted particularly for commutator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a sliding contact piece suitable for a commutator system of a small direct current machine.

[Prior art]

Sliding pieces in commutator systems for small direct current machines must meet high requirements 2°C regarding lifespan and surprisingly small JJ resistance.

Traditional commutator systems consist of carbon rods or metal brushes and a cooperating commutator, which is made of sheet metal or wire. The material is copper or, in high-grade cases, alloys of noble metals that are conductive and have particularly low wear and tear, such as Ag-C.
u10 is used as the composition. In order to improve reliability, the contact surfaces are in particular gilded. Such embodiments are disclosed, for example, in DE 1615169 and DE 2041238. This kind of commutator system is completely technical due to the complicated structure of the commutator, the use of multiple precious metals, and the inability to maintain contact resistance to a satisfactory level. The above is also unsatisfactory. For this reason, it has been proposed that the commutator be formed as a layered indigo flow commutator on a ceramic or plastic base, above all in order to minimize the noise caused by the use of the material. I)
I) -WP No. 101246, DD-WPPI32
No. 7191 (IPCH0IR39104) and DD-WP
156654 (IPCHOIR59106) discloses such a layered commutator.

Layered commutators are a preferred solution to commutators made of cotton sheet metal (in view of the economy of the laminated material).

However, this ridge commutator has the disadvantage that the durability of the contact layer is limited to some extent due to the small thickness of the layers and the thickness of the metal coating. In an attempt to eliminate these drawbacks by thickening the layer, VC efforts are being made to create a thicker layer with as low a degree of porosity as possible, as well as strong co-layer properties and a dry surface. , through technical difficulties.

Layers with the required property 7 have so far only reached the order of 10 μm roughness. In the past, the actual usable range was within the range of 2 to 3 μm, and the lifespan was correspondingly short.

Attempts have been made to overcome this drawback with extremely hard metal layers. For example, 1) D-WP101246
In the publication, PR with the highest mechanical abrasion resistance
An i x P y layer is disclosed and is well known as a commutator contact layer.

However, this layer is highly hard and requires a lot of wear and tear on the brush. Further, the electrical characteristics of N1xPy are relatively poor, and therefore the contact resistance is large. In order to suppress the resistance of the contact portion for a long period of time, it is necessary to pay attention to the Kg increasing effect.

Commutator systems with such layers are therefore unsuitable for direct current machine applications. West German Perimeter No. 176
3B7B and 2124425 disclose coating the elements of the commutator system, namely the commutator or the brushes, with a thin metal layer, in particular a thin metal layer with a thickness of 06 to 6 μηt. . However, in this case it clearly occurs that the energy of the firing point of the commutator system, which is also suitable for sliding action, is absorbed by the metal with a low melting point. Such a red metal layer becomes difficult to maintain contact resistance due to oxidation. When using a precious metal layer as a covering layer, as is known in expensive commutator systems, its lifetime is essentially a matter of the thickness of that layer and thus the cost incurred by the precious metal.

DD-WP No. 156654 (IPC [10f R
45106') vcliIMj 'Jk ill' I
AI pole jail; Haishi law is disclosed. According to K, NlxP is deposited on a ceramic substrate by a chemical reduction method.
A y-layer is formed on which an electrically noble metal contact layer is coated. These Ni and Py layers are used as electrodes during plating, and their thickness is therefore 50 nm, which is extremely thin. It is determined by the actual consumption rate of the layer, and when that layer is exhausted, this! The flow system no longer exhibits the required properties.

[Purpose of the invention]

The object of the present invention is to obtain at low cost a sliding contact piece with high stability of electrical characteristics and long life.

[Means of invention]

The basic purpose of this invention is to produce a high-grade sliding contact piece, especially one related to the commutator system of a small DC machine. The sliding contact piece according to the present invention has little wear and tear, and there is no oxidation phenomenon, but the temperature is extremely low. In addition, the use of precious metals is also a sliding contact piece in which a contact layer is provided on a support base, and the present invention achieves the above purpose by creating a layer of surface irregularities between the support base and the contact layer. The solution is to form a hard amorphous intermediate layer having a cauliflower-like structure with a diameter of 05 to 10 μm. Wj is composed of N i x P y for the purpose.

The phosphorus content in the N1xPy layer is between 5 and 10%. In another embodiment, the intermediate layer is formed by +1q of N1xBy. The degree of unevenness of the surface structure is preferably 6μ.

The contact layer uses gold, silver, or an alloy of gold and haladium as a sieve-grade contact. In very rare cases also use a copper layer. The thickness of the contact layer should be between 05 and 10 μm, with this layer thickness being at least slightly thicker than the depth of the irregularities of the intermediate layer.

The sliding contact piece of the present invention made in this way, which is particularly suitable for the commutator system of a small DC machine equipped with metal brushes, has a long service life and high stability in contact resistance. . In the case of the invention, mechanical or electrical loads never lead to wear of the support base. This is probably because the uneven tops of the intermediate layer carry the mechanical load and strongly retard further wear of the contact layer.

A portion of the contact layer sticks to the valleys of the irregularities in the intermediate layer and remains, maintaining the excellent properties of the sliding contact piece.

In the scope of commutator systems, this sliding contact can be arranged on the commutator, on the brushes, or on both. It is not limited only to commutator systems. The advantage of the present invention is that the precious metal layer required in the case of high-grade sliding contacts can be made smaller.
? It can also be used for

The support base on which the sliding contact piece is arranged is made of an insulator or a conductor depending on whether or not current is passed through it. In laminar commutators or sliding rings, an electrically conductive layer, for example a copper layer, is formed on an insulating support substrate underlying the sliding contact according to the invention.

[Example 1] A copper layer is formed as a conductive layer on a cylindrical ceramic substrate by plating. According to DD-WP No. 156654, this substrate is chemically produced and its surface is metallized. The copper layer is approximately 10 μm thick. The surface unevenness is approximately 6 μm, and an N1xPy layer having a thickness of approximately 4 μm is formed as an intermediate layer on this copper layer functioning as a conductive layer by chemical reduction plating. A contact layer of gold is formed on the other surface. This layer formed by plating has a thickness of approximately 6 μm.

The intermediate layer made of N1xPy has a cauliflower-like surface with a degree of unevenness of 31 tm. The contact resistance between the commutator equipped with the sliding contact piece of the present invention and the brush made of AgPd50 is 5 mV or less, and the commutator has extremely good durability.

[Embodiment 2] In the second embodiment, a sliding contact piece of this light is placed on a normal adjusting fluid.

N1xP obtained by chemical reduction on an elongated (curved surface)
The Y layer is arranged to have a thickness of 5 μm and an unevenness of 4 μm. On top of this layer a 10 μm thick copper layer is applied by electroplating.

Agent Hikaru Esaki Agent Mitsufumi Ezaki

Claims (1)

[Claims] 1. In particular, a sliding contact piece for a commutator system of a small DC machine, which has a contact layer on the surface of a supporting base, and has a cauliflower-like thickness of 0.5 to 5 μm between the base and the contact layer. A convenient amorphous intermediate layer with a rough surface and a thickness of 1 to 10 μm is
A sliding contact piece with a distinctive feature. 2. The sliding contact piece described in claim 1,
It is characterized in that the intermediate layer consists of N1xP. 5. The sliding contact piece described in claim 1,
The intermediate layer is made of Ni and By. 4. Special feature W1: A sliding contact piece according to claim 1 or 2, characterized in that the contact layer is made of gold, silver, or an alloy of silver and palladium. 5. A sliding contact piece according to claim 1 or 2, characterized in that the contact layer is made of copper. & A sliding contact piece according to claim 4 or 5, wherein the contact layer has a thickness of 0.6 to 10 μm, and is at least slightly smaller than the depth of the unevenness on the surface of the intermediate layer. It is characterized by being thick.