US623922A

US623922A - Brake-shoe

Info

Publication number: US623922A
Authority: US
Publication date: 1899-04-25
Anticipated expiration: 1916-04-25

Description

No. 623,922. Patented Apr. 25, I899.

' P. B. & J. MABGBEGOB.

BRAKE SHOE.

[Application filed Nqv. 10, 1898.)

(No Model.)

ATTORNEY NlTED STATES M ATENT Prion.

PETER B. MAC-GREGOR AND JOHN MAOGREGOR, OF ELMIRA, NE\V YORK.

SHOE.

SPEGIFICATION formingpart of Letters Patent No. 623,922, dated April 25, 1899.

Application filed November 10, 189.8.

T0 alt whom it may concern:

Be it known that we, PETER B. MACGREGOR and JOHN MACGREGOR, citizens of the United States, residing at Elmira, in the county of Chemung and State of New York, have invented a new and useful Improvement in Brake-Shoes, of which the following isaspec-ification.

Our invention relates to improvements in brake-shoes in which blocks or slugs of a softer metal are embedded in a cast-iron body; and the object of our improvements is to provide a brake-shoe of this type which can be manufactured at a reduced cost and in which the bearing surface will be composed of abrading and adhesive parts so designed and proportioned as to produce improved results both as to the wearing and braking qualities of the shoe and as to the life of the car-wheel upon which the shoe is used.

To accomplish the object of our improvements preferably by so forming the brake shoe where it bears upon the wheel as to cause the shoe to contact with the tread of the Wheel outside of where the Wear is produced by the rails and by forming the contact-surface of the shoe of cast-iron broken up by the soft-metal slugs, which are of a nature peculiarly adapted for this purpose and in which our invention mainly lies, the two metals of said contact-surface being in such proportions that the cast-iron portions will be sufficient to abrade and wear away the wheel in conformity to the Wear of the rails, and the soft; metal portions will be sufficient to provide the necessary adhesive quality to the brakeshoe.

A brake-shoe embodying our improvements is shown in the accompanying drawings, in which- Figure 1 represents the shoe in perspective; Fig. 2, a section on the line co m in Fig. 1, representing the brake-shoe in contact with a wheel; and Fig. 3, a detail showing a pun ching or slug as utilized by us.

In the several views similar letters refer to similar parts.

A represents the portion of the brake-shoe face which contacts with the tread of the wheel, 13 a cut-away portion to relieve the tread of the wheel of wear from the shoe where said tread is worn by the rails, and 0 Serial No- 696, O55. (No model.)

.portions, as indicated at C, Fig. 2, or with slugs of a harder material than the cast-iron, whereby the periphery of the wheel-flange will be dressed down proportionately as the tread of the wheel is Worn. This feature of the shoe, however, is old, and we do not claim it as our invention.

The face A of the brake-shoe is broken up by a number of soft-metal blocks or slugs D, these slugs being in such proportion as to give the desired abrasive and adhesive qualities to the face A of the brake-shoe. These slugs are also placed in a staggered position relatively to one another along the face of the shoe, therebyincreasing the strength of the shoe and providing the face of the shoe with the adhesive quality across the entire width of its face. We produce these slugs by punching them from iron or steel plates or bars preferably three-quarters, seven-eighths, or an inch in thickness, the metal selected being softer than the cast-iron body of the shoe. In the process of punching the metal is compressed to the extent of about one-sixteenth of an inch and the punchings or slugs assume the shape shown more particularly in Fig. 3 of the drawings. The compression of the metal in the slugs renders them much more tough and durable, so that while retaining their adhesive qualities they will last much longer and the brake-shoe containing them will remain in service for a greater length of time than if the slugs were uncompressed. Moreover, the form and character of these slugs render them especially adaptable for molding purposes. The greater specific gravity of the slugs, due to their compression, causes them to remain where set in the mold without danger of their floating out of place when the molten metal is poured into the mold. For this reason the use of chaplets, nails, &c.', to hold the slugs in place is eliminated and the labor and cost of molding much decreased. Finally, as the slugs are punched out of the metal their peripheral surfaces will be bright and unoxidized, this causing a perfect adhesion with the cast metal, and the tapering shape of the slugs increases the hold of the cast metal upon them. Vhile these slugs can be especially prepared by punching them from any desirable metal, we have found that the pu nchin gs thrown out by bridge-works and other structural works are most admirably adapted for this purpose, and we are therefore enabled to use to a great extent what would otherwise be scrap of little value. It will therefore be seen that we produce a brake-shoe havingincreased durability with all the adhesive qualities requisite,and at the same time by utilizing largely scrap material and by reducing the labor and cost of molding we materially reduce the cost of such a brake-shoe.

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

1. A brake-shoe composed of a cast-iron body portion having embedded therein, with their small ends at the contact-face of the PETER B. MACGREGOR. JOHN MACGREGOR.

Vitnesses:

A. S. DIVEN, C. TRACEY STAGG.