US643668A - Brake-shoe. - Google Patents

Description

Patented Feb. 20, I900. C. E. MARK.

BRAKE SHOE.

ion filed July 16, 1897'. Ben

ewed Oct. 23, 1899.)

(Applicat (No Model.)

UNITED STATES CHARLIE E. MARK, OF CHICAGO, ILLINOIS.

BRAKE-SHOE.

SPECIFICATION forming part of Letters Patent Al'o. 643,668, dated February 20, 1900.

Application filed July 16, 1897. Renewed October 23, 1899. Serial No. 734,531. (No model.)

terial of which varies in hardness.

Heretofore brake-shoes have been provided the body portion of which is made up or composed of a hard metal and the braking-surface formed in a varying degree of hardness by relatively soft metals or materials.

The object of my invention in one respect is to produce a brake-shoe having a base or body portion of relatively soft metal and having a braking-surface formed by added harder metal secured in the base or body portion.

My invention also has for a further object the provision of means whereby the added portion of harder metal may be readily adj ustedin position upon the softer base or body portion and securely held in place.

My invention has certain other objects in View, and consists in certain features about to be described, reference being nowhad to the accompanying drawings, in which Figure 1 is a face view of my improved brake-shoe. Fig. 2 is a side view of the same, partly broken away to show the base or body portion in section. Fig. 3 is a side view of the brake-shoe, partly broken away and in a position assumed before being bent. Fig. 4 is a cross-section on the line m w of Fig. 1. Fig. 5 is a cross-section showing a modified form of metal piece.

In carrying out my invention I provide a body portion A of the brake-shoe, which is of a material capable of being bent from a straight position, as shown in Fig. 3, into the proper curved position, as shown in Fig. 2. In the face of this body portion A, I out or form the series of recesses B, which extend trans versely of the braking-surface D of the shoe. I also provide the metal insert-pieces E, one of which is more clearly shown in Fig. 5, having the braking-surface E for the tread of the wheel and the curved surface E for the flange.

These insert-pieces E are of a greater degree I of hardness than the body portion A of the brake-shoe. As shown more clearly in Fig. 3, the insert-pieces E are disposed or positioned within the transverse recesses B by placing them within these recesses when the body portion A is straightened out, as shown in said figure. As the insert-pieces E are wedge-shaped, when the body portion is bent into the curved position of the brake-shoe, as shown in Fig. 1, the sides of the recesses B engage upon and bite the insert-pieces in place and securely hold them against any possible displacement.

In the ordinary brake-shoe it has been customary to construct the body portion of a cast metal or of some kind of metal which does not readily bend and which, in fact, cannot be bent. In some instances metal pieces have been added to the hard base in the shape of plugs, and resort has been had to chilling the surface of the shoe in order to obtain varying degrees of hardness, the chills being distributed unevenly over said surface. In the form of brake-shoe as just described by me it is evident that a stratum of harder material relative to the body portion is distributed upon the braking surface of the shoe and arranged, as shown, transversely thereof. It will be observed that the insertpieces E may readily be inserted in the cavities or recesses B with readiness and that when the body portion A is bent into its curved position these insert-pieces are firmly and securely held in place. The curved surface E which maybe termed the flange-engaging extension, presents at intervals strata of material harder than the body portion A, and thus as the tread of the wheel is worn away by the brake-shoe the flange of the wheel is also Worn away to an equal degree.

In Fig. 4 I have shown an insert-piece E, which is unprovided with the flan ge-engaging extension E Having thus described my invention,what I claim as new therein, and desire to secure by Letters Patent, is

1. A brake-shoe comprising a body part formed of relatively soft bendable metal bent so as to provide a concave braking-surface; and a series of relatively hard insert-pieces confined in recesses or cavities formed in the ICO braking-surface of the body part before the ed as a result of such bending, said insert bending thereof, and held therein bypressure pieces consisting of a tread portion and a exerted as a result of such bending. flange portion formed integrally therewith.

2. A brake-shoe comprising a body part In testimony whereof I affix my signature 5 formed of relatively soft bendable metal bent in presence of two witnesses.

so as to provide a concave braking-surface; 1 7 1 and a series of relatively hard insert-pieces CHARLIE MARK confined in recesses or cavities formed in the Witnesses: body part of the shoe before the bending L. M. BULKLEY, ro thereof, and held therein by pressure exert- CHAS. G. BULKLEY.

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