US425435A - Brush-holder for dynamo-electric machines or motors - Google Patents

Description

(No Model.)

F. A. LA ROCHE. BRUSH HOLDER FOR DYNAMO ELECTRIC MACHINES OR MOTORS.

Patented Apr. 15, 1890.

U ITED "STATES.

PATENT OFFICE.

FREDRICK A. LAROOIIE, or PHILADELPHIA, PENNSYLVANIA.

BRUSH-HOLDER FOR DYNAMO-ELECTRIC MACHINES oR Mo'ToRs.

SPECIFICATION forming .part of Letters Patent No. 425,435, dated April" 15, 1890.

Application filed December -'7, 1389. Serial No. 382,984. (No nib'delo" To aZ Z whom, it may concern: I life 1t known that I, FREDRIOK A. LARocHE, a citizen of the United States, and a resident of the city of Philadelphia and State of Pennsylvania, have invented a new and useful 1mproveincnt in Brush-Holders for Dynamos or Motors, of which the following is a clear and sufiicient specification, reference being had to the drawings annexed.

My invention relates principally to brushholders intended to be used with carbon or ,other rigid or inelastic brushes, but can be used with advantage also with other brushes now in-use.

In the present form of-brush-holders the brush is held without any provision for lateral adjustment except the elasticity of the brush itself. On this account the brushes are usually made of thin strips of copper or other elastic conductor, as carbon or other rigid brushes, tho igh used, required an extremely careful adjustment to make an even ,contact between the commutator and the brush, because if they do not lie fiat against the commutator, and thus make an even contact, the commutator wears unevenly and the machine sparks; To make an even contact and to enable the brush to lie automatically flat against the commutator is the object of my invention, which consists, essentially, in

'making the clamp holding the brush automatically adjustable, as will be now more particularly described.

Figure 1 shows an end View of a brushholder containing my invention and the adjacent parts of a dynamo. Fig. 2 is a side View of a partof a brush-holder containing my invention. Fig. 3 shows the brush and commutator, the dotted lines showing the various positions in which the brush might be. Fig. 4: is a sketch of a modification of my invention.

' I attach to the frame of a dynamo or motor of any common type a brush-holder, which I have shown in Fig. 1, of the common adjustable form as to the supporting portions,which consist, as shown, of the rocker-arms B B, "1-

brating on the spindle U, to which it may be clamped at'any desired angle by the set-screw D, and having backwardly-extending spindlesE E,;on which are placed the yokes F F,

i that are impelled inwardly by the tensionsprings G G. These parts, however,are allwell known, and form no limitationupon my invention, whichimay be applied to the supporting port-ion of any form of brush-holder. To this portion of a clamp I, in which I secure ,the brush, so as to allow a free oscillatory movement of the-latter in the direction of its width. practice by pivotingthe clamp to the yoke F, preferably, though not necessarily, at a right angle with the rocker-arm, by a pivot or equivalent device. A modification is shown in Fig. 4, in which the desired automatic adjustability of the brush-holder is obtained by attaching the clamp holding the brush to suggest itself to a workman skilled in the art-as, for instance, by fastening it (see Fig. 4). to a fastened 'to the spindle E of abrush-holder. Thisspring H can take the-place of the tension-spring G, accomplish the same results as the pivot shown in Fig. the brush K, which I generally make of a piece of carbon. The advantages of the use of this material arewell known, but have not hitherto been made much use of on account of the difli culty of adjusting it in the ordinary rigid brush-holder, caused by its inelasticity. I do not, however, limit myself to a brush of carbon, as the advantages of my invention extend equally to a. brush of a rigid-piece of copper or other conducting material;=or, if desired, the ordinary brush can be inserted.

It can readily be seen that a brushplaced in a brush-holder having an oscillating motion, as above described, will adjust itself so brnsh-holder (tothe yoke B, as shown in my illustrations) I attach the This I effect in 7 v spring H, the other end of which I have shown while its sidewise oscillations 3. .In this clamp I is secured as to lie fiat against and make an even contact with the commutator if placed in any of i the positions shown by the dotted lines in Fig. 3, and will be aided to fall into position.

by the rotation of the commutator, and'that though it is preferable that the clamp osci'l-- late substantially in a plane parallel to the axis of the commutator and be placed directly opposite the latter very large variations can be made without interfering with the capacity of the brush-holder to allow the brush to. adjust itself and to make an even contact with the commutator.

I operate my machine as follows: In the commutator, and do this even if the level of: m

clamp I, I secure the brushes K K, which, if they are made of carbon or other rigid material, I preferably make extend far enough out from the clamps to bring the flat portion into contact with the commutator if their ends are rough. I then start the machine. The brushes immediately adjust themselves, so that there is no sparking or wearing of the the latter is not perfect,either through wear or defective construction. v

What I claim, and desire to secure by Letters Patent, is-

1. The combination, with the commutator and frame-work of a dynamo or motor, of a rigid brush lying in a plane tangent to the commutator-and a brush-holder attached to 4 said frame-work and freely and automati- -cally movable in two intersecting planes, substantially as described.

2. The combination, with the commutator and frame-work of a dynamo or'motor, of a rigid brush lying in a plane parallel toa plane tangent to the surface. of the commutator,-a brush-holder freely and automatically movable in two intersecting planes, and

u a spring impelling the brush down on the commutator, substantially as and for the purpose set forth.

3. The combination of the commutator and I frame-work 0i a dynamo or motor with a brush-holder consisting of a supporting-piece attached to said frame-work, freely and antomatically movable in a plane substantially perpendicular to the axis of the commutator, and a clamping piece attached to said supporting-piece, freely and automatically movable in a plane substantially parallel to the axis of the commutator, substantially as and for the purpose set forth. 4. The combination, with the commutator ,andframe-work ot a dynamo or motor, of the supporting portion of a brush-holder, freely rigid brush lying wholly in a. plane parallel to a plane tangent to the surface of the commutator and a brush-holder freely and automaticall-y. movable both in a plane substantially at right angles with the commutatorshaft and in a plane substantially parallel to the surface of the commutator, substantially as and for the purpose set forth.

. FREDRICK A. LAROCHE.

lvitnessesi MARK WILKS COLLET, GEO. H. Rarson.

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