US1695865A

US1695865A - Brush holder

Info

Publication number: US1695865A
Application number: US174107A
Authority: US
Inventors: Hans C Specht
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1927-03-10
Filing date: 1927-03-10
Publication date: 1928-12-18
Anticipated expiration: 1945-12-18

Description

Dec. T8, 192s. 1,695,865

- H. c. SPECHT BRUSH HOLDER Filed March 10, 1927 INVENTOR WTNESSES: Wi w- Hans Cdpec/zif ATTORNEY Patented Dec. 18, 1928.

UNITED STATES PATENT J OFFICE- EARS e. mom. or wmxnwssvm, rmmnvsnm, xsemnb r0 wns'rmenouss amen/1c & mimic-rem comm t, a coaroaxrren or PENiiSYLVANIA.

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Application filed much 16, m1. Serial No. 174,107.

My invention relates to brush-holding devices and articularly to brush-holding devices for e ectric motors of the repulsion-induction type. g

In electric motors of the repulsion-induction type, it is frequently desirable to vary the posltion of the brushes relative to the comneutral axis by rotating the brush-holding device in a circularhole provided in the motor frame. As the siaeof such circular hole was limited by the available space, this construction necessitated the "disposition of the brush at an angle, in order to obtain the desired angle or lead with respect to the neutral axis. Various means for locking the brush-holding device in this position have been provided, but have been unsatisfactory, either becaum they did not provide apositive locking ar- 1 rangementor because they were so complicatedthat they easily became inoperative or were too expensive to manufacture.

By my invention", I provide a brush-holding device which is simple in construction and easy to manufacture. and which is provided with means for positively locking it in position. i

provide a brusholding device which comprises means for positioning the brush ofa repulsion-induction motor on either side of the neutral osition, I I

Another object of'my invention is toprovide a device of the aboverharacte of such shape and design that the angle o contact between the brush and the commutator may readily be variedTby simple changes in the design without eiiecting the position of lead of the brush.

A further object of my invention is to provide a device of the above character which comprises simple means for positively securing the device against displacement in any direction except radially outward.

In the accompanying drawing,

Fig. 1 is a plan view of my invention,

Fig. 2 is a horizontal sectional view of the device taken along the line 11-11 of Fig. 3,

' Fig. 3 is a. vertical sectional view of the device, 7 i I Fig. 4 is a fra mentary View, in elevation, ofamotor embo ying my invention, and g 1g. 5 is a plan view of a portion of the motor frame embodying m invention.

An approximately circu ar disk 1 is provided with a large, eccentrically disposed, tubular, depending portion 2, and a small. auxiliary dependingportion 3, both of which extend substantially perpendicularly to the plane of the'face of the disk. The large proectmg portion 2 is provided with a perforation or chamber 4 extending longitudinally therethrough, constituting a brush cartridge in which is disposed a carbon brush 5, a spring 6 for positioning the brush 5, and a iiexible conductor member 7 shunting current around thespringfi. The brush 5 is slidably positioned in the chamber and is disposed in the lower portion thereof. The spring 6 is arranged to cooperate with the brush and tends to expel the brush from the chamber. It will be understood that two brushes 5 are utilized in a repulsion motor.

The upper portion of the chamber is enlarged and is provided with screw threads 8 Y to receive a cap screw 9 for closing the end of the chamber g and maintaining the spring 6 in position. The cap screw 9 is provided with a longitudinal cavity 11 extending into the lower portion thereof: Ametallic terminal 1-2, arranged to fit the cavity 11 and having I a cylindrical, downwardly projecting boss 13 One of the o eets of my invention is to is provided for makin connection between the flexible shunt 7 an theframe of the motor; The projecting boss .13 of the terminal 12 is inserted ,in the upper end ofthe spring,

thereby ositionin the same andgrounding lhebru es 5 on t enframe. I

The smaller projecting portion '3 of the brush-holding device has across section of substantially diamond shape, as shown in dotted lines in Fig. 1, and is disposed diametrically opposite the larger projecting portion 2. The extreme length of the cross section of the smaller projecting portion is made the same as the diameter of the larger projecting portion for purposes which will be subsequently disclosed.

Referring to Figs. 4: and 5, av portion of an electric motor 14 is shown. A flat boss 15, provided with two circular openings 16 is disposed in the motor frame at the commutator end. The openings 16 are of the proper size and spacing to :mcommodate the two projecting

portions

2 and 3 of the brush-holding device which secured in place by means of two

machine screws

18 and 19 extending through small holes 21 and. 22, in the diskshaped portion 1 and screwed into the tapped holes 23 and 24-, in the motor frame 16. It is noted that the cover plate 1 is symmetrical with respect to two axes, one passing through the centers ot the two large holes 16, and the other at rig angles thereto and midway between the said holes. The fastening

screws

18 and 19 are syn'nnetrical with respect to both axes. whereby the brushholder may be reversed through 180.

It will he unden'tood that two brushes are provided for repulsion motor operation. li hen it is desir d to reverse the rotation of the motor by sh. i side of the

neutral screws

18 and 19 are removed and the brush holder is lifted from its position in the boss 15. The larger projecting portion 2 is inserted in the opening in the boss formerly occupied by the small projecting portion 3, and the smaller projecting portion 3 is inserted in the other opening in the hose, thereby bringing the brush-holding device 17 into a position in which it is rotated substantially 18 around the axis of the disk.

A raised arrow is provided in the upper face of the disk which indicates the direction oi? rotation of the motor.

In manufacturing this device, I am able to vary the angle of contact between the brush and the commutator without varying the distance of the point o't contact from neutral position. and vice versa. This is accomplished by varying the distance between the two projecting portions 2 and of the brushholder.

It will be apparent. from the above descri ption. that my device is extremely simple and. eas to manufacture and has relatively few paation and inexpensive to construct.

In addition, it apparent that the abovedescribed arrangement of parts causes the device to be firmly secured in position and maintained against accidental displacement. In addition, it is very easy to reverse the angle of lead or the brush relative to the neutral point. since it is necessary merely to remove two screws.

thereby melting it dependable in oper- By utilizing a diamoml-shape cross-section for the smaller projecting portion 25, I: am able to make the device more compact in design, as will be readily seen, without sacrilicing any strength or rigidity in the device. It is apparent however. that it would he possible to utilize various other shapes in the corn struction of this device.

\Vhile I have described my invention. setting forth a specific example oi. the construction thereof. it is apparent that my invention not limited to the details shown and described, and I desire that. the appended claims shall be given the broadest interpretation consistent with their wording and the prior art.

I claim as my invention 1. In a dynamo-electric machine, a machine frame having a plurality of openings therein, and a lDlllSll-llOlCllUQ device removably mounted in the said frame and having a plurality of projections arranged to lit in the said openings, whereby the device is maintained in any one of a plurality of positions.

In a dynamo-electric machine. a machine frame having a plurality of openings therein. a brush-holding device having a plurality oi projecting portions arranged to lit the said openings, one of said projecting portions being hollow, and a brush slidably supj'iorted in the said hollow projecting portion of: the device.

3. A motor having a frame, ln'ushholders and a commutator cylinder. charac ived by means for reversing the angle of lead of each brush with respect to an axis of the motor.

said means comprising a portion ot the frame having two holes therein on opposit sides oi. said axis the brushholder comprising a cover plate extending over both of said ho es and having a downwardly extending hr 1h cartridge extending thrmigh eithe one oi said holes. according to the position o l he. brush.

4. A ln'ushholder comj'irising a cover plate which is syn'imetrical with l'tF l ltt'li to two axes, retaining means symmetrically dispo-rd with respect to both of said axe whereby said brushholder may be reversed through 180. and an eccentrically disposed downwardly projecting brush cartridge.

In testimony whereof. I have hereunto s1 :hscribed my name this th day of March. 102?.

HANS C. SPEC H 'I.

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