US722606A

US722606A - Electrical contact-brush and method of producing same.

Info

Publication number: US722606A
Application number: US12092802A
Authority: US
Inventors: Homer N Motsinger
Original assignee: MOTSINGER DEVICE Manufacturing Co
Current assignee: MOTSINGER DEVICE MANUFACTURING Co
Priority date: 1902-08-25
Filing date: 1902-08-25
Publication date: 1903-03-10
Anticipated expiration: 1920-03-10

Description

PATENTED MAR. 10, 1903.

v H. N. MOTSINGER. ELECTRICAL CONTACT BRUSH AND METHOD OF PRODUCING SAME.

APPLICATION FILED AUG. 25, 1902.

r0 MODEL.

IKK i I K K K I K I! INK i l X I K K X I K I N I I l i K K KI 7 I I I I i i h i i I I II IN VE N 70/? Homer N.Motsinger A TTOBNE m f WITNESSES W Mourns P UNIT D STATES PATENT OFFICE.

HOMER N. MOTSINGER, OF PENDLE'ION, INDIANA, ASSIGNOR TO MOTSINGER DEVICE MANUFACTURING COMPANY, OF PENDLETON, INDIANA, A COR- PORATION OF INDIANA.

ELECTRICAL CONTACT-BRUSH AND METHOD OF PRODUCING SAME.

SPEGIFIGATION forming part of Letters Patent No. 722,606, dated March 10, 1903.

Application filed August 25, 1902.

To all whom it may concern:

Be it known that 1, HOMER N. MOTSINGER, a citizen of the United States, residing at Pendleton, in the county of Madison and State of 5 Indiana,haveinvented certain new and useful Improvements in Electrical Contact-Brushes and Method of Producing Same, of which the following is a specification. '1

The object of my invention is to producea IO composite contact-brush formed of metal and carbon inwhich the carbon forms a central core protected by an external shell of metallic gauze, the arrangement being such that the gauze serves as a binder or containingr 5 shell for the carbon, so that any distortion of the brush due to external pressure exerted by a holder cannot disintegrate the carbon insuch manner as to cause it to separate from the metal, the brush thus formed being par- 20 ticularly adapted for use in hollow holders,

so that a'bimetal contact may be secured between the brush and holder instead of a contact between the metal of the holder and the carbon, as is the casein that class of brushes 2 5 where a metallic core is embedded in a shell of carbon.

A further object of my invention is to provide a method of producing my improved brush by means of which the external wrapping of gauze may be secured to the carbon in such manner that it may not become displaced.

The accompanying drawings illustrate my invention.

Figure 1 is an enlarged longitudinal sectionof a desirable form. Fig. 2 is a side elevation of the form shown in Fig. 1, in which the gauze or wrapping is laid on straight. Fig. 3 is a view similar to Fig. 2, showing the gauze 4o laid on bias. Fig. 4. is a section on line 4 4.

in Fig. 2; and Fig. 5 is a side elevation, full size, of a brush particularly designed for small machines.

The brush consists of a central core 10, of

45 carbon or similar conducting material. Wrapped about the core is a sheet or portion of gauze 11, the ends of which are secured together in any suitable manner, as by solder 12, so as to hold the gauze about the core. If

Serial No. 120,928. (No model.)

desired, the core 11 may first be provided with a thin shell of material 13, preferably applied electrolytically in the ordinary manner.

In order to make a successful and .commercial brush, it is essential that the wrapping be so positively secured to the core that it may not become readily displaced, and in order to accomplish this result I have adopted the following method:

Strips of gauze are out which in width are somewhat less than the circumference of the core 10, and these strips are then heated so as to cause expansion thereof, the transverse strands of the gauze expanding longitudinally so as to increase the width of the strips. These strips while heated are then rolled about the core 10, the edges coming close together and being secured by any suitable means-such, for instance, as a connectingbar of solder 12which becomes intimately united with the adjacent edges of the gauze. When this is accomplished, the resultant contraction of the gauze, due to cooling, clamps the gauze shell tightly about the core, so that the shell becomes intimately associated with the core and cannot be readily displaced. If the core has been preliminarily provided with an electrolytic coacting of copper 13, the solder of course sticks to this core. By forming a brush in this manner, especially in the cylindrical form shown, it may be readily inserted into a tubular holder and a metallic contact obtained throughout the length of the periphery of the brush with the holder. If desired, a metal cap 14. may be secured to the outer end of the brush and intimately connected with the wrapping of the gauze, as shown in Fig. 3, if desired. Any 'external pressure unequally applied to the periphery of a brush formed in this manner will have less tendency to crack the carbon than in a case where the carbon forms an external metallic gauze the edges of which are brought together and connected by solder.

2. A contact-brush consisting of a central core of carbon, a shell or casing of electrolytic metal, and an external wrapping of gauze.

3. A contact-brush consisting of a central core of carbon, a shell or casing of electrolytic metal, and an external wrapping of gauze the edges of which are brought together and secured by solder.

4. A contact-brush consisting of a central core of carbon, and an external shell or gauze shrunk upon the core.