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Low Wear Brush Placement

IP.com Disclosure Number: IPCOM000088587D
Original Publication Date: 1977-Jul-01
Included in the Prior Art Database: 2005-Mar-04
Document File: 2 page(s) / 35K

Publishing Venue

IBM

Related People

Broom, WE: AUTHOR [+2]

Abstract

This article describes a method for arranging the brush on the armature of a motor so as to reduce armature wear.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 86% of the total text.

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Low Wear Brush Placement

This article describes a method for arranging the brush on the armature of a motor so as to reduce armature wear.

Fig. 1A depicts the end view of an armature showing four brushes positioned about the periphery of the armature. Of course, instead of a four-pole motor armature/brush configuration, a two-pole motor armature/ brush configuration may be used. Fig. 1B depicts a side view of the armature showing track 1 which is created by the two negative brushes and track 2 which is created by the two positive brushes. With this configuration, it was observed that the commutator suffers high wear in one brush track while the other track experiences little wear. As a result of the high wear, the armature had to be changed regularly.

This high wear can be solved by eliminating the continuous run in one direction. This would prevent the oxide build-up which tends to wear the armature.

Another solution for the problem is depicted in Figs. 2A and 2B. In Fig. 2A, all the brushes (that is, both positive and negative) are placed in the same track. This configuration helps to reduce the oxide build-up and, hence, armature wear. However, due to the high rubbing between the brushes and the single armature track, the wear problem may still be substantial. This approach is, therefore, the least recommended.

In Fig. 2B the wear problem is solved by placing alternate brushes in the same track. For example, the positive and negative brushes are arranged to ru...