US147571A - Improvement in railway-car brakes - Google Patents

Description

l.. RADDIN.

yRailway Car-Brakes. No.l47,57l. e .PatentedFeb.17,1s74.

the shafts by the hand-wheels.

UNITED STATES PATENT OFFICE JOHN nAnniN, on LYNN, MASSACHUSETTS.

Vlli/IPRovEMianl'lf IN RAILWAY-CAR BRAKES.

Specification forming part of Letters Patent No. 147,571, dated February 17, 1874; application tiled November 3, 1871.

` Mechanism for Railway-Gars; and I do hereby declare that the following, taken in connection c with the drawings which accompany and form part of this specification, is a description of my invention sufficient to enable those skilled in the art to practice it. v

This invention relates to the construction and arrangement of a safety-brake mechanism for railway-cars.

Ordinarily, as is well known, brakes are applied to the wheels of cars by drawing the brake-spurs to thewheel-peripheries by brakelevers, rods, and chains, the chains being woundby the brakeman upon the windlasses or shafts of the hand-turned wheels at the end platforms of the cars. When released from strain, the chains unwind and the brakes loosen their hold upon the wheels, suitable springs throwing them back from the wheel-peripheries. By such method of applying and operr ating brakes, much time is always consumed in operating the brakes, or in starting to operlate them when a train is to be quickly arrested. To obviate this, a mechanismhas been devised by which, by means 'of coiled springs placed on the windlass or chaii'i-winding shafts, the brakes are applied by the stress of springs, and are thrown from the wheels by turning For reasons not necessary herein to mention, such brake mechanism'has proved impractical, and is not now in use, return having been made to the simpler brakes brought into action by hand.

In my invention, I have sought to devise a simple but reliable organization by which the brakes should be automatically thrown against the wheels, and should be drawn therefrom by hand, instead of being applied by hand, and springing from the wheels when the windlasses are released. For this purpose I hang each brake-fra1ne at the outer end of the cartruek, and connect the cross bars or beams (to which the brakes are fastened) together by strong contractile springs, the stress of which shall draw the brake-shoes tightly against the wheels, so that when thc sprin gs are free thus to operate the brakes, the friction of the brakeshoes upon the wheels shall be sufficient toarrest the car in the shortest space of time or length of distance in which it is practical to arrest a car by pressure upon the Wheels, the length of time or space being, of course, dependent upon the speed at which the car may be ruiming. Of course the pressure must not be sufficient to lock the wheels or cause them to slide, and there may be mechanism combined with the springs for increasing or lessening their stress. The pressure may be induced by weights acting directly on the brakeframes; but this is not so practical as the springs, they being more eficient for the purpose. rEhe brakes so operated are connected, by suitable rods, chains, and levers, with the brake-windlass, and this mechanism being so arranged that the springs are expanded and the brakes drawn from the wheels by winding the chains upon the windlass-shafts, suitable ratchet-and-pawl mechanism being employed to hold the brake-frames in position. It is in this method of operating brakes that my invention consists.

The drawing represents in reverse plan and in side elevation a car-truck andplatform embodying the invention.

a denotesthe truck-frame; b b, c c, the two pairs of wheels; d c, the axles journaled in suitable boxes, the truck, wheels, axles, boxes, and housings being constructed and arranged in the ordinary manner. h i denote two brake bars or rails, to the inner sides of which the brakes k k l l are fixed, the brake bars or rails being hung from the end rails m of the truckframe a, and so that the brakes can swing freely against or from the wheels. To the two ends of the two brake-frames, at each side of the truck, the opposite ends of a spring, n or o, are fastened or connected, each spring being preferably a long coiled contractile spring, the stress of which tends to draw inward the brake-frames and to force the brakes against the wheels, and producing such action of the brakes whenever the brakes are at liberty to so move against the wheels. Each brakeframe is connected, by rods pq, levers r, and chains s, with a winding-shaft, t, upon the top of which, above the platform u, is a handreleasing the ratchet from it, the stress of the springs will immediately throw the brakes against the Wheels and stop the car.

The pawl may be connected by a line, y, with the engine, so that by drawing upon the line, the engineer can immediately apply all of the brakes to a train, Without reference to the brakemen, the duty of the brakemen being to again dranT the brakes from the Wheels preparatory to the start of the train; or the brakemanto the respective cars may trip the pawls, and thereby brin g the brakes into effective operation. In either case provision exists for instant and e'ective application of all of the brakes, instead of the application effected only by Winding up the brake-chains. Weights z may be used instead of the springs, but the lsprings are preferred.

Each brake is made with an iron shoe, asin ordinary brakes; but betweenrthe shoe and the brake-body I apply a cushion, j, of caout chouc or similar elastic material or compound, which shall tend to create uniform pressure from the Whole surface of the shoe, instead of from parts thereof, as is the case when the shoe is rigidly attached.

AInstead of connecting the brake-frames by springs placed at the outside of the Wheels, as shown, they may be connected by a spring or springs placed between the Wheels.

I do not claim a device in which the brakeA shoe is forced against the Wheel by a spring acting indirectlyY and through intervenin g mechanism upon the brakebeain but I do claim, and desire to secure by Letters Patente In a railwaycar brake, the combination of springs u o, secured to the brake-bars h i, with lever r, rod q, chain s, and brakerod t, all substantially as set forth.

VJOHN nAnnrN.

Witnesses:

FRANcIs GoULn, r M. W. FROTHINGHAM.

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