US562346A

US562346A - Brake-shoe

Info

Publication number: US562346A
Authority: US
Publication date: 1896-06-16
Anticipated expiration: 1913-06-16

Description

v (No' Model.)

' W. W. WHITOOMB.

BRAKE SHOE.

Patented June 16, 1896,

UNITED STATES PATENT OFFICE.

\VILLIAM WV. WHITCOMB, BROOKLINE, MASSACHUSETTS, ASSIGNOR TO THE COMPOSITE BRAKE-SHOE COMPANY, OF BOSTON, MASSACHUSETTS.

BRAKE-SHOE.

SPECIFICATION forming part of Letters Patent No. 562,346, dated June 16, 1896.

Application filed April 10, 1896. Serial No. 586,955. (No model.)

To ctZZ whom it may concern:

Be it known that I, WILLIAM XV. NVHIT- COMB, residing in Brookline, in the county of Norfolk and State of Massachusetts, have invented an Improvement in Brake-Shoes, of which the following description, inconnection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention relates to brake-shoes, and has for its object to increase the efliciency of the same, as will be hereinafter described.

The invention is more particularly an improvement upon that class of brake-shoes having a longitudinal groove or channel of a width substantially equal to the width of the tread of the rail upon which the car-wheel runs.

Brake-shoes of the class just described are provided with the longitudinal groove re ferred to, so that the portion of the wheel worn by contact with the tread of the rail may not be subjected to extra wear by the brake-shoe, which action, if permitted, would materially shorten the life of the car-wheel. These brake-shoes are efficientfor the purpose specified, but this efliciency in this respect is obtained at a sacrifice to the braking efficiency of the shoe, by reason of the fact that a substantially large amount of braking surface is absent from the brake-shoe.

It is the object of this invention to improve brake-shoes of the class referred to, whereby increased braking effect may be obtained without wearing effect of the brake-shoe upon that part of the wheel worn by the rail, and I accomplish my invention by providing the longitudinal groove, which is preferably enlar d at its rear portion, with a brakingsurface of softer material than the main portion of the brake-shoe, and preferably wooden sections or blocks firmly secured or locked in the said longitudinal groove, which softer material acts on the portion of the wheel worn by the rail and increases the braking efficiency of the shoe without detrimental wearing action on the wheel.

These and other features of this invention will be pointed out'in the claims at the end of this specification.

Figure]. is a plan view of a car-wheel with a brake-shoe embodying this invention applied thereto and shown in section; Fig. 2, a side elevation of the brake-shoe shown in Fig. 1 looking toward the right; Fig. 3, a front elevation'of the brake-shoe shown in Fig. 2 looking toward the left; Fig. 4, an elevation of the rear or back side of the brake-shoe shown in Fig. 2 looking toward the right; Figs. 5 and 6, front elevations of modified forms of brake-shoes embodying this invention; and 7, a sectional detail to be referred to, the section being taken on the line 7 7, Fig. 6.

Referring to Fig. 1, A represents a carwheel having the flange a and which may be of any suitable or usual construction, such as now commonly used on railways. The car-wheel A has cooperating with it a brakeshoe A, which may be made of any suitable or usual metal, such as cast iron or steel, and which consists of a body portion a, provided with alongitudinal groove, channel, or slot a of a width at the face a of the shoe substantially equal to the width of the rail upon which the car-wheel runs and not herein shown, the said groove or channel being preferably enlarged at or near its rear portion or end, as at of, which enlargement is herein shown as dovetail in form and preferably extends the entire length of the depth of the groove or channel a The groove or channel a is less than the thickness of the shoe, so as to leave a solid back or bottom for the channel integral with the shoe, and, in accordance with this invention, the said groove or channel receives within it a body or filling of softer material than the metal of which the shoe is composed, and the saidbody or filling may and preferably will be composed of blocks or sections Z) of wood or other non-metallic Z) are driven or otherwise forced into the groove or channel m as represented in Fig. 1.

The filling or inserted braking-surface is preferably made in sections and inserted into the groove or channel a so as to leave airspaces 19 between adjacent sections or blocks, and the back wall of the channel or groove a is preferably provided with one or more holes or openings b communicating with the airspaces 19 for the passage of dust or other particles as the shoe is worn, and the blocks or sections 7) may be provided with longitudinal holes or openings 5 in line with each other for the circulation of air longitudinally through the shoe, which air-circulation serves to convey away the heat-currents and diminishes the heating of the shoe.

The back wall of the slot a may also be provided, if desired, with additional holes or openings b (see Fig. 4:) between the holes or openings 17 to still further ventilate the shoe and thereby still further diminish the heating of the shoe.

The brake-shoe shown in Figs. 1 to 4:, inclusive, is constructed for engagement with the flange a of the wheel, and is provided with a groove 19 to embrace the flange CL, and this groove b may, if desired, be provided with one or more wooden or other plugs or blocks Z9 inserted into and secured in suitable sockets in the walls of said groove. So, also, the wheel engaging face a may be provided, if desired, with wooden or other plugs Z9 By reference to Fig. 1, it will be seen that the portion of the wheel A which runs upon and is worn by the rail is engaged by the wooden sections or blocks when the brake is set, and by reason of the blocks or sections being made of softer material than the wheel 1 and of softer material than the body of the brake-shoe the wheel is not worn by the said 1: sections or blocks, but the adhesion of the: shoe to the wheel is increased and conse-: quently the braking efficiency of the shoe is increased. I may prefer to make the softer braking material, which fills the groove or slot of wood in the form of sections or blocks, as herein shown, and to lock the same in the said groove or channel, but I do not desire to limit my invention in this respect, as a single block d, of wood or non-metallic or other composition or metal softer than the bodyof the shoe, may be inserted or otherwise put into the said slot, channel, orgroove, as represented in Fig. 6. When composition is used, the locking device or wedge Z) may be dispensed with and the enlargement or recess in the back of the slot or channel a depended upon to retain the braking material in the said slot or channel. So, also, I prefer to ventilate the brake-shoe substantially as described, but the ventilating-openings may be omitted without detracting from the action of the braking material in the slot or channel a 7 In Figs. 5 and 6 I have shown my invention as embodied in a brake-shoe which is not constructed for engagement with the flange of the wheel.

In operation as the harder braking-surface a of the shoe engages the portion of the wheel not worn by the rail and wears away the wheel, the filling or body of softer material is being worn by the portion of the wheel which makes contact with the rail, and, as it is worn, the said body or filling adapts itself to the form of the portion of the wheel worn by the rail and consequently maintains a maximum braking-surface in contact with the said wheel.

I claim- 1. A brake-shoe consisting of a body por tion provided with a longitudinal slot, channel or groove of a width substantially equal to the width of that portion of the car-wheel worn by the rail and of a depth less than the thickness of the shoe to leave a solid bottom for the slot integral with the shoe, a body of softer material than the shoe in the said slot, channel or groove and adapted to engage that portion of the wheel worn by the rail to form a braking-surface therefor, and means within the said slot for retaining the body of softer material therein, substantially as and for the purpose specified.

2. A brake-shoe consisting of a body portion provided with a longitudinal slot or channel of a width substantially equal to the width of that portion of the car-wheel worn by the rail and provided with an enlargement within it and having a solid bottom integral with the shoe, and a body of softer material inserted into said slot or channel and extended into the enlargement thereof, and adapted to engage that portion of the wheel worn by the rail to form a braking-surface therefor, substantially as described.

3. A brake-shoe consisting of a body portion provided with a longitudinal slot, channel or groove of a width substantially equal to the width of that portion of the car-wheel worn by the rail and provided with a solid bottom integral with the shoe, and blocks or sections of non-metallic material inserted into .said slot, and means to lock said blocks or space communicating with the opening in the back wall of the channel or slot, substantially as and for the purpose specified.

5. A brake-shoe consisting of a body portion provided with a longitudinal slot, channel or groove of a width substantially equal to the width of that portion of the car-Wheel In testimony whereof I have signed my Worn by the rail, and a body of softer matename to this specification in the presence of rial inserted into said slot to form a brakingtWo subscribing Witnesses.

surface for the portion of the Wheel Worn by WILLIAM W. WHITCOMB. 5 the rail and provided With a 10n gitudinal open- Witness es ing forming an air-circulating passage, sub- J AS. H. CHURCHILL,

stantially as and for the purpose specified. J. MURPHY.