US374273A - Brake-shoe - Google Patents

Description

(No Modrel.)

G.'M. SARGENT.

BRAKE SHOE. N. 374,273. Patented Dec. 6, 1887.

UNITED STATES PATENT OFFICE.

GEORGE M. SARGENT, OF CHICAGO, ILLINOIS.

BRAKE-SHOE.

SPECIFICATION forming part of Letters Patent No. 374,273, dated December 6, 1887. I

Application filed September 2S, 1887. Serial No. 250,920.

To all` whom t may concern:

Be it known that I, GEORGE M. SARGENT, a citizen of the United States, and a resident of Chicago, Cook county, Illinois, have invented certain new and useful Improvements in BrakeShoes, of which the following is a specification.

My invention relates to that class of brakeshoes which, by reason of certain portions thereof being harder than other parts, serves to dress down or wear away the Wheel at certain points, so as to preserve the proper shape of the tread or wearing parts and prevent it from grooving under` the combined wear of the rails and shoe; and it consists of a shoe having certain parts of its wearingface hardcned by means of chills in the process of casting, as will be hereinafter fully set forth, -whercby to dress thewearing-face of the wheel as it is worn away.

It is Well known that the peripheries ofcarwheels become Worn Inost rapidly at certain points of the tread near the flange, so that there are formed therein annular depressions or grooves, while the flanges become both thickened and lengthened, thus seriously impairing the efficiency of the wheels and rendering it often necessary to discard them much sooner than would be required were the proper outline of the periphery preserved. To preserve this desirable outline, and thus obviate the defects referred to,various expedients have been resorted to, such as inserting cutting blocks or plates of hard material into the softer' metal of the brake-shoe and arranging them in various manners, so as to insure the desired wearing or cutting action. One such construction forms the subject-matter of an application, No. 230,028, filed by me on the -7th day of March, 1837'.`

My present invention differs from such invention, in that in place of the hard cutting blocks or strips there used I chill certain sections ofthe wearingface of the shoe outside the line of the rail-tread,and also in the dangegroove.

In order that my invention may be better understood,l have illustrated it in the accompanying sheet of drawings, wherein- Figurel is a sectional view illustrating the construction of the shoe, and also the effect of wear upon a car-wheel. Fig. 2is a face View of the shoe. Figs. 3 and 4 show different forms of the invention.

(No model.)

As the effect of the rails is to wear the tread 5 5 hollow, as indicated by dotted lines, Fig. 1, and/at the same time to lengthen the flange so that it becomes liable to cut the bolts of switches and spring-frogs, I harden certain sections, a a, of the brake-shoe face A and of the grooved flange A,shaped to fit the wheelflange by chills B, placed in molds.

As the effect of the rails is to wear the Wheeltread most rapidly at the point x, the greatest cutting action, in order to properly dress the tread, is required along the outer edge thereof, and this may be secured by such construction as that shown in Figs. 3 and 4, wherein a greater portion of the wearface of the brakeshoe adjacent to the outer edge of the Wheel is hardened than is nearer to the center of the tread,where less friction or cutting is to be done. This effect may be secured in various ways, two being illustrated. That in Fig. 3 consists in making the number of 75 hardened sections adjacent to the outer edge of the wheel greater than those adjacent to the tread portion,while in Fig. 5 the same end is secured by tapering the sections toward the tread-engaging part of the shoe. In this way the shoe bears upon and consequently wears down that part of the wheel not worn by the rail, and as a consequence the face of the wheel is kept true and smooth. y

I am aware that cast brakesshoes have been provided with chilled portions extending entirely across the face thereof, and I therefore disclaim the broad idea of forming dressingsurfaces on abralte-shoe by Ineansofhardened chilled sections.

I claim- 1. A brake-shoe provided with dressing or cutting sections along the edge outside the tread, consisting of chilled portions of the shoe, substantially as described.

2. A brake-shoe having a grooved flange, A', shaped to the wheel-ange, in which are hardened chilled sections to dress down the Wheel-iiange and preventits lengthening, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

GEORGE M. SARGENT.

IOO

Witnesses:

J. C. DAVIS, J. B. SWAN.

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