JPS6055841A - Motor - 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 Field of the Invention The present invention relates to an electric motor that transmits current using a commutator and brushes.

Conventional configurations and their problems Conventionally, in electric motors that combine a commutator and brushes that work together, the surface roughness of the commutator is adjusted by appropriate polishing, and during the manufacturing process of the commutator and brush surfaces. Generally, the contact stability between the commutator and the brushes is improved by removing as much contamination as possible.

However, even in an electric motor whose contact stability has been improved by such a method, depending on the operating environment conditions, the rotational performance may deteriorate, and in extreme cases, the motor may even become unable to rotate.

The causes of such rotational defects can be broadly classified into the following two types.

(1) Increase in contact resistance and short circuit between commutator pieces due to generation of abrasion powder due to commutator-brush sliding.

(2) Increase in contact resistance due to the formation of so-called blackened powder due to the adsorption of organic gases from the outside.

OBJECTS OF THE INVENTION It is an object of the present invention to prevent malfunctions in conventional electric motors caused by the above-mentioned causes and to provide an electric motor with excellent rotational performance.

Structure of the Invention The present invention provides a thin organic layer containing at least one of paraffin, phthalate coaster, nylon, or silicone compounds on the surface of a commutator or brush produced by the general method described above. This electric motor is characterized by a thin organic material layer that improves rotational performance.

DESCRIPTION OF THE EMBODIMENTS FIG. 1 shows an organic layer 3 formed by dropping the organic substance-1 of the present invention or an organic solvent containing it on the surface of a commutator 1 or a brush 2 which has been polished and cleaned by a conventional method. FIG. 2 shows a commutator and brush having a commutator 1. These are the results of a running test of a small electric motor equipped with the brush 2 for 25 hours under actual conditions of use to investigate the relationship between the thickness of the organic layer and rotational performance. In FIG. 2, the rotational performance rank shown on the vertical axis is determined by measuring the current waveform with an oscilloscope during the running test and determining the rank as shown in FIG. That is, rank O means that there is no abnormality in the current waveform, and rank 5 means that a state in which the current becomes zero (so-called OFF point) is observed for 3 seconds or more. In this kind of rotational performance evaluation, it is assumed that motors with rank 2 or higher will experience rotational defects in practical use.The ratio between the rotational performance rank determined by the rank 2 link test and the incidence of rotational defects in practical motors is 1:1. As a result of checking Seki, it was found.

The average value of the rotational performance rank in a run-second test under the same conditions for a conventional small electric motor is 1.5 to 2.
Some even indicated 2 or more.

On the other hand, in the case of a small electric motor comprising a commutator 1 and a brush 2 on which the organic layer 3 of the present invention is formed, as shown in FIG. , 5-200 //,
In the range of m, the average rotational performance rank I+:f is 1.
6 or less, it can be seen that the rotation performance is superior to the conventional one.

We tested 41 machines that are effective in improving rotational performance.
The results show that paraffin, Nisder phthalate, nylon, and silicone compounds are effective in the same thickness range, although there is a 2'l:1 difference in the performance ranking of the 1Φ class. Met.

Regarding the types of compounds, puffin-based compounds are viscous liquids to solids, that is, those with a carbon number of 6 to 207 degrees, while phthalic acid Nisderite-based compounds include dioctipafclay I- and sibutyl phthalate-1.i viscous liquids. Among the nylon-based products, low molecular weight products, and among the silicone-based products, the CRYS, OY/L'-based products were comparatively better. Among these compounds, the rotational performance of silicone-based compounds was found to deteriorate in long-term durability tests compared to other compounds. The cause of this is that when used for a long time, some silicone compounds may
It is thought that this is because the contact resistance increases due to the change to iO2. On the other hand, other paraffin-based, fucuric acid ester/I/based and nylon-based compounds were also excellent in terms of durability.

It is presumed that there are two reasons why these layers of organic matter impair the rotational performance of the electric motor.

(1) Suppressing the generation of wear particles due to improved sliding properties due to the lubrication effect.

(2) Prevention of adsorption of organic gases from the outside 11. Prevents the formation of blackened powder.

These two effects correspond to the causes of rotational failure in the conventional electric motor described above, and simultaneously contribute effectively to improving rotational performance.

In addition, the reason why the optimal thickness for this effect is recognized is as follows.
o, s less than 7zm, the above-mentioned effects are insufficient,
This is considered to be because when the thickness exceeds 200 μm, an increase in contact resistance due to organic matter has an adverse effect.

In addition to the above-mentioned dropping method, the organic material layer of the present invention can be formed by using an organic material or a method of immersing it in a solvent (1/ζ, liquid compound). When doing so, it can be formed by immersing the commutator and brush in the same amount as the dripping amount, and the solid compound can be similarly formed by dissolving it in an organic solvent.Furthermore, When it is desired to form a thin layer, there is an advantage that the thickness of the layer can be easily adjusted by changing the dilution rate with the organic solvent.

Effects of the Invention As described above, the present invention allows the rotational performance to be easily and inexpensively improved, and has excellent effects for electric four-wheels.

[Brief explanation of drawings]

11xl (a), (b) U A cross-sectional view of the commutator and brush according to the present invention, FIG. 2 is a diagram showing the relationship between rotational performance and the thickness of the organic layer, and FIGS. f) is a diagram showing the current waveform and rotational performance rank of a small electric motor in a running test. 1.Commutator, 2.Brush, 3..Organic substance layer. Names of J111 Patent Attorney Toshi Nakao Male Haga1
Fig. 1 Fig. 3 (α) Lump 0 (C) (e) La ″22 Lump 4 Lump 3 (f no. 5

Claims (2)

[Claims] (1) It has a commutator piece and at least one brush cooperating with the commutator piece, and an organic substance layer containing at least 1s of a paraffin-based, phthalate ester-based, and silicone-based compound on the surface of the commutator piece and the brush. An electric motor characterized by being coated with. (2) The electric motor according to claim 1, wherein the organic layer has a thickness of 0.5 to 200/Im.