US531707A - Brush for dynamo-electric machines - Google Patents

Description

(No Model.)

J. B. WALLACE. BRUSH FOR DYNAMO ELECTRIC MAUHINES. No. 531,707;

Patented Jan. 1, 1895.

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JOHN B. \VALIAACE, OF ANSONIA, CONNECTICUT, ASSIGNOR TO THE IVALLACE ELECTRIC COMPANY, OF ILLINOIS.

BRUSH FOR DYNAMO-ELECTRIC MACHINES.

SPECIFICATION forming part of Letters Patent No. 531,707, dated January 1, 1895.

Application filed April 30, 1894.

To aZZ whom it may concern.-

Be it known that I, JOHN B. \VALLAOE, a citizen of the United States, residing at Ansonia, in the county of New Haven and State of Connecticut, have invented certain new and useful Improvements in Brushes for Dynamo-Electric Machines, of which the following is a specification.

My invention relates to brushes for dynamo-electric machines and has for its object to provide a brush in which there shall be a minimum of tendency to cause sparking.

My invention is illustrated in the accompanying drawings, Wherein- Figure 1 is a perspective view of a brush. Fig. 2is a cross section through the same. Fig. 3 is a cross section through a modification. Fig. 4 is a cross section through a different form of brush. Fig. 5 is a perspective of the preferred form of brush, somewhat diagrammatic.

Like parts are indicated by the same letters in all the figures.

A is the body of the brush, composed preferably of metallic gauze or cloth folded in the form indicated. This cloth or gauze is prefreably composed of a good conductor so that the body of the brush is composed of high conducting material.

B B are strips on the sides of the body and they are of high resistance metal or material and they are secured to the body in any desired manner as by clamps or by soldering the parts at the end of the brush.

C is a wrapping of high resistance material which passes entirely around the body of the brush covering both sides and edges, and is composed of any desired substance if only it be of high resistance, and it is formed and attached in any desired manner.

D is a wrapper of high resistance metallic gauze or cloth and it is formed continuous with or attached to the metallic gauze or cloth of the body of the brush and is then Wrapped about the body of the brush as many times as may be necessary. In this latter,

which is the preferred form of my brush, I have one mass of gauze or metallic cloth, the

Serial No. 509,511. (No model.)

body portion of high conducting power, and the outer folds or covering which entirely surround the body, composed of high resist ance gauze or cloth.

It is quite evident that the high resistance wrapping of any kind of. material, preferably of gauze or cloth, may be applied to a body of other than gauze or cloth construction, and it is equally evident that the high resistance gauze or cloth may be applied to the sides only of the body of the brush. By having the entire brush made of gauze or wire cloth the sparking is reduced to a minimum, the body of the brush being protected at its edges as Well as at its sides, and the gauze or cloth of the high resistance material being closely set to the body of the brush. This same result to a degree, comes about when the high resistance gauze wrapping is used to surround a brush Whose body is composed of material other than wire cloth or gauze. On the other hand, the wire cloth or gauze of the outer or high resistance portion of the brush very closely incorporates itself with the cloth or gauze of the body, so that the separation of the parts is impossible to the degree which is possible in the case of laminated brushes. This is due to the fact that the masses or projecting ends of the fibers of the gauze of the brush become entangled and entwined and associated together, and thus in the process of use the separation of the high from the low resistance material is reduced to a minimum.

In some cases the brush may be surrounded by a high resistance material not in the form of gauze or cloth, though I prefer the latter.

I claim- 1. A brush for dynamo-electric machines consisting of a body of gauze or cloth composed of a good conducting material with an enclosing or surrounding Wrapper of gauze or cloth of a high resistance substance or material.

2. A brush for dynamo-electric machines consisting of a body composed of gauze or cloth of a good conducting substance or ma terial, with layers of cloth or gauze of high resistance material on the sides thereof.

8. A brush for dynamo-electric machines covers the sides and edges of said body and consisting of a body of good conducting mais itself composed of high resistance mateterial with a surrounding covering composed rial the Whole constituting a flexible brush. IO

of a gauze or cloth of high resistance material. JOHN B. W ALLAOE. 5 4. A brush for dynamo-electric machines Witnesses:

consisting of a body of good conducting ma- J NO. H. OOULTER,

terial with a surrounding covering; which W'ALTER J. GUNTHORP.

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