US585872A - Robert lundell - Google Patents

Description

(No Model) v R. LUNDELL. BRUSH HOLDER FOR DYNAMO ELECTRIC MACHINES.

Patented July 6, 1897.

INVENTORZ WITNE By 111': A/zomey UNITED STATES PATENT OFFICE.

ROBERT LUNDELL, OF BROOKLYN, NEIV YORK, ASSIGNOR OF TlVO-TIIIRDS CONDUIT AND INSULATIOI COMPANY, OF NEIV TO THE INTERIOR YORK, N. Y.

BRUSH-HOLDER FOR DYNAMO-ELECTRIC MACHINES.

SPECIFICATION forming part of Letters Patent No. 585,872, dated July 6, 1897.

Application filed July 11, 1896. Serial No. 598,801. (No model.)

To all whont it may concern:

Be it known that I, ROBERT LUNDELL, a citizen of the United States, residing at Brook lyn, in the'county of Kings and State of New York, have made a new and useful Improvement in Holding and Adjusting Devices for the Com m u tator-Brushes of Dynamo-Electric Machines or Electric Motors, of which the followingis a specification.

My invention relates particularly to improvements upon an invention described and claimed in a prior patent granted to me on the 26th day of September, 1893, and numbered 505,665; and it has for its objects, first, the construction of a brush holding and adjusting device which will prevent chattering of the brushes when the machine is running; second, the construction of a brush-holding device which will be adapted to give substantially constant pressure of the brush upon the commutator for varying lengths of said brush as it wears away; third, the arrange ment and adaption of such a brush-holding device for use with equal facility whether the commutator be rotated in one direction or the other, and, fourth, the adaptation of abrushholder for brushes of different thickness.

In the brush-holding device described and claimed in my prior patent above referred to there is arranged a yielding spring adapted to feed the brush forward as it is worn away. I have discovered that with a brush-holder of that form however, chattering often occurs, and particularly when the commutator is runnin gin a reverse direction from that for which it is normally set. WVith the type of device described in my prior patent it was also impossible to render the pressure constant for various lengths of brushes.

My present invention also contemplates this adjustable feature, and the especial points of novelty and utility of my invention will be described in the following specificationand particularly pointed outin the claims at the end thereof.

Referring now to the drawings, Figure 1 is a plan View of my improved brush-holder. Fig. 2 is a longitudinal sectional view taken through Fig. 1 on the line 2 2 and as seen looking at that figure from the bottom toward the top of the drawing in the direction of the arrows, an imaginary commutator being also shown rotating from right to left. Fig. 3 is a side elevational view as seen looking at Fig. 1 from the left-hand toward the right-hand side of the drawing, the adjusting devices being removed and the invisible portions as seen from that view being shown in dotted lines. Fig. 4 is a longitudinal sectional view of Fig. l on the line 4 t and as seen looking at that figure from the bottom toward the top of the drawing, this figure of the drawings also indicating an imaginary commutator rotating in the reverse direction from that shown in Fig. 1 and a diagrammatic view of the forces acting upon the brush when the machine is in motion.

Referring now to the drawings in detail, 11 represents a brnslrholdin g device adapted to sustain in a rectangular guideway a carbon brush B with its lower end resting upon a commutator O, 77/2 being the rectangularshaped shank of the brush-holder, provided with the usual shoulder h and screw-threaded neck 72,3 for securing it (the holder) to the brush-rockers in awell-known manner.

I1 is a laterally-extending yoke integral with the brush-holding part II and provided at its rear end with an upwardly-extending portion H which has in turn a vertical slot h, said parts being adapted to secure the adjustable parts of my improved brush-holder.

A is an L-shaped metallic part having sufficient bearing against the inner face and top portion of the brush B to hold it firmly in position in the rectangular guideway of the stationary part H. This part A is provided with lugs or cars a, to which is pivoted bya pin 19 and an extension (I a cylindrical part D, adapted to sustain by a shoulder d one end of a spiral spring S, d being a cylindrical neck adapted to move freely within the inner surface 6 of a second pivoted portion E, secured by a pin c and extension e and lugs or cars g to an adjustable arm G, having a rectangular-shaped extension which is adapted to move vertically in the rectangular slot h in the upwardly-extendin g portion H The outer surface of the second pivoted portion E is screw-threaded and adapted to receive an adjusting-nut F, provided with a shoulder for bearing adjustably against the free end of the spring S.

w is a split washer, and T a screw-threaded adjusting-nut adapted to secure the adjustable arm G at any desired height in the slot 7t, being a split pin in the outer end of the screw-threaded extension g g for preventing the absolute removal of the nut T.

The operation of myimproved brush-holder is as follows: The brush B is slipped in place in the rectangular guideway of the holder II, and the L-shaped adjustable holding device A is placed in the position shown in Figs. 1, 2, and l. The adjustable arm G is then pressed downward until the pressure of the parts gives to the brush the desired firmness against the inner face of the holder H and downward pressure against the commutator C. The set-nut T is then screwed firmly home against the split washer to, and the apparatus is ready for use. Should it be desirable at any time, owing to the wear of the brush upon the commutator, to give a further advancement to the holding device the nut l is simply turned to the right, so as to cause the spring S to act with the required pressure upon the movable part D and hence through the pivotal part upon the adjustable holder A.

Should further advancement be required, owing to the wearing away of the lower end of the brush B, it is only necessary to release the set-screw T and give to the adjustable arm G a downward m ovem cut-,so as to maintain the angular position of all of the adjustable parts in the relation fixed upon at the first setting of said parts, after which the set-nut T is firmly secured as before. It will be seen that through this double adjustment of the parts G T, E F, and D A, I am enabled to give to brushes of varying lengths a pressure upon the commutator which is substantially constant and at the same time to avoid any possibility of chattering.

In Fig. I have shown the operation of th device under the contingency of a rotation of the commutator in a reverse direction from that shown in Fig. 2, it being apparent from the parallelogram of forces illustrated by the letters a; and 3 and the normal frictional force due to the action of the commutator indicated at .2 that the brush B can never leave the inner surface of the stationary holding part II, thereby avoiding any possibility of chattering and also avoiding the evil effects of raised conmiuta-tor-bars. Vith this improved brush-holding device I find it possible to utilize brushes of variable thickness and to enable one to use such brushes with substantially constant pressure upon the commutator and without any chatter whatever, no matter in which direction said commutator may be rotating.

My improved holding device may also be used in any place where it is desired to conduct electricity from a stationary to a moving conductor, and vice versa, and my claims include all such uses.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States, is-

1. A commutator-brush holder provided with two sets of adjusting devices, one of which sets of adjusting devices tends to give to the brush downward pressure against the commutator and a lateral or side pressure against the stationary part of the holder, and the other gives to all of said parts vertical adjustment so as to adapt the entire structure for brushes of various lengths, substan tially as described.

2. A commutator-brush holder provided with a stationary guideway for the brush and a movable part adapted to bear against the brush in two directions, said movable part being pivotally secured to an adjustable device, one part of which is mechanically connected with the stationary part of the holder, substantially as described.

3. A commutator-brush holder consisting of a stationary part and a movable part adapted to exert a pressure upon the brush in two directions, in combination with adjustable means connecting said movable part with the stationary part whereby the pressure may be varied as desired, substantially as described.

I. A commutator-brush holder consisting of a stationary part provided with a guideway for the brush, a movable part pivotally connected to spring-actuated adjusting mechanism, which adjusting mechanism is in turn secured to the stationary part, all of said parts being so arranged that the adjusting mechanism tends to give to the brush movement in two directions, substantially as described.

5. A commutator-brush holder consisting of a stationary part provided with a guideway for the brush, a movable part adapted to bear against the brush in two directions and pivotally secured to a spring-actuated adjusting device which in turn is pivotally secured to a second adjusting device having mechanical connection with the stationary part of the holder, substantially as described.

In testimony whereof I have hereunto subscribed my name this 30th day of June, 1896.

ROBERT LITNDELL.

\Vitnesses:

C. J. KIN'INER, M. M. ROBINSON.

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