US674679A - Brake-shoe. - Google Patents

Description

No. 674,679. Patented May 2|, I901. G. H. GILMAN & J. H. BROWN.

B B A K E S H 0 E.

4 Application filed Dec. 1, 1900.

(No Model.)

UNITED STATES PATENT OFFICE.

GEORGE I-I. GILMAN AND JAMES H. BROWN, OF TACOMA, WASHINGTON.

BRAKE-SHOE.

SPECIFICATION forming part of Letters Patent No. 674,679, dated May 21, 1901.

Application filed December 1. 1900. Serial No. 38,333. (No model.)

road cars, but also capable of use on cars of other railways.

The object of the invention is the production of a brake-shoe which shall be as light as possible in weight, shall prevent the look ing and consequent sliding of the wheels caused by foreign substances getting between the shoe and the wheel, shall be provided with means for keeping the shoe cool during the application of the brake, shall increase the value of the worn-out shoes by reason of the absence of steel or wrought-iron plugs used in some makes, shall be so constructed as to be strongest at the center, where the greatest strength is required, and therefore least liable to break in service, shall present soft portions for contact with the flange of the wheel and hard portions for contact with the tread, and shall be so constructed as to prevent toorapid wear of the shoe.

\Vith this object in view our invention consists in a brake-shoe the parts of which are constructed, arranged, and combined in amanner hereinafter fully described and afterward specifically claimed.

In the accompanying drawings, which illustrate one embodiment of our invention, Figure 1 illustrates a view in side elevation of a brake-shoe constructed in accordance with our invention, parts not exposed to view being indicated by dotted lines; and Fig. 2 represents a face view of the same.

Like letters of reference indicate the same parts in both figures of the drawings.

A indicates the main body of the shoe, and B the face thereof, the latter being inwardly curved, as is usual, to fit the periphery of the wheel to which it is to be applied.

0 indicates a lug or boss on the rear of the brake-shoe, provided with a slot or opening D to receive a pin or key for securing the shoe to the brake-head. Inasmuch as the brakehead and the key may be of any well-known and usual construction, it has not been considered necessary to illustrate or describe them in this application, and we have shown the slot or opening D only in dotted lines.

E E E E indicate apertures or openings through the brake-shoe from the front or face to the rear thereof. The inner sides of said apertures, as shown by dotted lines at F in Fig. 1, are substantially at right angles to the face, while the outer sides (shown by dotted lines at G, Fig. 1) are inclined upwardly from the rear to the front face of the brake-shoe, said inclined sides G being shown in full lines in Fig. 2. These inclined sides G of the apertures E, as before stated, are the outer sides and incline outward from the rear to the front of the shoe, so that the openings in the-face are much longer than the openings in the back, the apertures being of substantially the same width throughout.

In the manufacture of the shoe the whole device is molded of cast metal, and steel or other suitable metal cores are used to form the apertures, so that the surfaces or walls of the apertures are chilled throughout their full extent from the face to the rear. In the application of the brake-shoe these chilled surfaces of the apertures afford hardened surfaces, which prevent rapid wear of the shoe, while not affecting its efficiency. The cored apertures being preferably near the ends of the shoe and the center cast solid, strength is afforded at the center,where the shoe receives the greatest strain,thereby rendering the shoe less liable to break in ordinary service.

Inasmuch as the whole face of the shoe, except the chilled surfaces of the apertures, is of ordinary soft cast metal, that portion of the shoe which comes in contact with the flange of the wheel is not hardened, thereby reducing the wear on the flange of the wheel to a minimum.

The apertures afford a free circulation of air through the shoe, thereby tending to keep the shoe cool during application.

' The weight of the shoe is lessened by the apertures, which also permit foreign substances which may enter between the shoe and the wheel to pass out through the shoe to the rear, thus preventing friction and consequent sliding of the wheels, whereby they may be flattened and rendered useless. It will be understood that these cored apertures may be varied in number, shape, and size as may be found practicable for use with different styles of shoes without departing from the spirit of our invention, and, if desired, the apertures need not extend entirely through the shoe, but be in the form of deep recesses, though we prefer that they should extend through the shoe.

Having thus fully described our invention, what we claim as new, and desire to secure by Letters Patent, is

1. A brake-shoe composed of ordinary soft, cast metal and provided with apertures extending through from the face to the rear, the walls only of said apertures being hardened or chilled during the process of casting the shoe, the rest of the entire shoe being composed of ordinary soft cast metal, substantially as described.

2. Abrake-shoe, composed of ordinary soft, cast metal and provided with apertures or recesses, the walls of said apertures being hardened or chilled during the process of casting the shoe, and said apertures being located between the center and the ends of the shoe, substantially as described.

3. A brake-shoe composed of ordinary soft,

walls of said apertures being hardened or chilled during the process of casting the shoe,

the inner faces of said apertures lying in planes substantially at right angles to the .face of the shoe and their outer faces being inclined outwardly from rear to front, substantially as described.

5. A brake-shoe composed of ordinary soft,

cast metal and provided with recesses, the walls only of said recesses being hardened or chilled during the process of casting the shoe, the rest of the entire shoe being composed of ordinary soft cast metal, substantially as described.

In testimony whereof we hereunto affix our signatures in presence of two witnesses.

' GEORGE H. GILMAN.

JAMES H. BROWN.

Witnesses:

FRANK J. MILLER, CHARLES A. MURRAY.

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