US328870A - Automatic car-brake - Google Patents

Description

(No Model.) 2 Sheets-Sheet 1.

W. A. WILDE.

AUTOMATIC UAR BRAKE.

if 39% *m g L M m P m 8 7% 5 w l m fl/H N w i W (No Model.) 2 Sheets-Sheet 2.

W. A. WILDE.

AUTOMATIG GAR BRAKE.

Patented Oct. 20, 1885.

HHHHIHH l lUnir'rn S'ra'rns arnw'r FFMZEQ WILLIAM A. WVILDE, OF CHICAGO, ILLINOIS.

AUTOMATIC CAR BRAKE.

SPECIFICATIQN forming part of Letters Patent No. 328,870, dated October 20, 1885.

Application filed March 5, 1885. Serial No. 157,719. (No model.)

To all whom, it may concern:

Be it known that 1, WILLIAM A. WILDE, a citizen of the United States, residing at Chi cago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Automatic OarBrakes; and I hereby declare the following to be a full, clear, and exact description of the same.

The invention forming the subject of the present application is in the nature of an improvement for use particularly with the de vice for which I filed an application for Letters Patent of the United States, Serial No. 135,238, June 18, 1884:, in which the brakes are normally and automatically set by a spring at a prescribed tension when the draw -bar occupies its normal position, and which permits the release of the brakes by the pulling outward or forcing inward of the draw-bar from its normal position.

It is the object of my present improvement to cause the spring which controls the operation of the brake in setting them automatically to increase the degree of their pressure against the wheels in proportion to the increase of weight produced by loading the car. Naturally, with the increase of the weight of a car its momentum, when the car is in motion, will be increased, whereby a force exerted upon the wheels of an unloaded car suflicient to brake them with the desired rapidity might not be sufficient to produce the result in a satisfactory manner upon those of a loaded car. Such is the case in the device referred to, upon which my present invention affords an improvement. The spring E therein is set to the necessary tension, normally, to maintain the brakes with sufticient pressure against the wheels to stop the motion of an empty car; but the same tension would not operate with sufiicient rapidity to stop the same car when loaded, owing to the increased momentum produced by the load.

To overcome this difficulty, my invention consists in automatically regulating the press ure of the brakes in setting them against the wheels of a car by the weight imposed upon the car; and my invention further consists in the particular construction by means of which I effect the desired end and in the details of such construction and combinations of parts composing my aforesaid improvements.

Referring to the drawings, Figure 1 is a longitudinal vertical section through the center of a car provided with my improved brake. Fig. 2 represents the bottom of a car having a portion broken away and provided with my improved brake, and Fig. 3 is a perspective view of a detail.

A is the draw-bar, provided with the usual draw-bar spring t,of common construction.

B is the lever, fulcrumed toward its center and pivoted toward one extremity to the drawbar,by the movements of which it is oscillated, and G is a lever, like the lever B,fulcrumed toward its center upon a suitable support, 5, which projects forward from the body bolster or cross-beam of the floor of the car. The free end of the lever B is connected to the inner end of the lever G by means of a suitable connecting medium, (shown in the drawings in the form of a chain, q,) and the same end of the lever O is connected with the draw-bar by similar connecting means, g.

D is the hand brake-wheel occupying the usual position of such devices upon cars, and connected with the connecting medium q, as shown, or with the inner end of the lever G, if preferred.

The parts thus far described are similar in their construction and operation and in their position to the corresponding parts shown and described in my aforesaid application, except as to the part g, which in the present application is connected directly with the drawbar instead of the lever.

E is a helical spring corresponding with the spring similarly designated in my aforesaid application, but attached at one extremity to the inner end and rear side of the lever O, the opposite end of which is connected with the brake-lever bya rod or chain, p,as clearly shown in Fig. 2 of the drawings. The spring E is set, on adjusting the device upon an unloaded car, by the attachment of its rear extremity, in the manner hereinafter described, to cause by its tension, through the medium of the lever O, the brakes to be normally maintained at a given pressure dependent upon the tension of the spring Eagainst the car-wheels,

from which they are released by the pulling outward of the draw-bar, which pulls the end of the lever O, with which it is connected, against the resistance of the spring E or by pushing in the draw-bar, whereby the lever I B operates, through the medium of the con- ,VIS

necting device q, to actuate the lever G in the same manner as described in my aforesaid application.

Fis the bell-crank lever, pivoted at its angle to a suitable support (shown in Fig. 1 of the drawings) at the side of a guide-beam of the draw-bar. The vertical end of the bellcrank F is formed into a hook, o, to which the rear extremity of the helical spring E is connected.

G and G are the transverse rigid beams of the car-truck, between which the spring bolster II, upon which the car rests, is supported in the usual manner.

I is a vertical frame pivoted toward its lower extremity as shown in Fig. 3 of the drawings, or, if preferred, rigidly connected to its support 9', which is secured upon the upper side of the rigid transverse truck-beam G, and the horizontal free end of the bellcrank is pivoted toward the upper extremity of the frameI or loosely adjusted between the vertical bars forming the same. If the entire hearing I is rigid in its position, it need not comprise a frame, as shown, but a single bar, for example, will answer the purpose, upon which the horizontal arm of the bell-crank may be adjusted to slide freely. Increase in the weight of the car will lessen its distance from the surface upon which the wheels rest by compressing the truck-spring which supports it, whereby the end of the bell-crank, where it is connected with the frame I, which is secured upon the rigid beam G, will be turned'in an upwalddirection, and thus force the hooked end inward, increasing the tension of the spring E, and, through the medium of the lever O and the connection therewith of the helical spring and brakes, the pressure of the latter against the wheels in proportion to the increase of weight of the car. The play of the hooked end of the bell crank is unlimited, since, owing to the construction of the frame I, no obstacle is placed in its path. It is therefore quite obvious that the pressure of the brakes against the wheels is automatically regulated, after being once set on the attachment of the device to an empty car, to correspond with the increased pressure upon the floor of the car of a load or the decreased pressure afforded by the removal of the entire load or a portion thereof, and that the brakes will automatically operate with like results whatever shall be the momentum of the moving car upon which my device is adjusted. It is of course desirable that the wearing away with use of the brake-shoes, which would operate to decrease their normal pressure against the wheels, shall be counteracted. I effect this by compensating for such wear by the manner (shown in Fig. 2 of the drawings) of connecting the brake-lever rod p with the lever G, which represents for the purpose a bolt, a, passing through the lever and screw-threaded toward one extremity, and provided with an eye, n, at its opposite end, into which eye the rod 9 is hooked, and upon the screw-threaded portion of which bolt a nut, m, is operated against the side of the lever to draw forward and thus shorten the rod.

It is not new, broadly, to provide means upon cars whereby the pressure of the brakes against the wheels shall automatically be adjusted according to the weight imposed upon the cars, and I do not intend that my claims shall admit of a construction so broad as to include all contrivances for this purpose, since I know of a brake device in which the brakes are set, without the use of any spring mech anism, by the forcing inward or drawing outward of the drawbar, and wherein an excess of pressure, a necessary consequence of the construction, and which would tend to permit flattening of the peripheries of the wheels, is

intended to be taken up by a relief-spring actuated through the medium of a bell-crank lever by and in proportion to the weight of a load imposed upon the car.

What I claim as new, and desire to secure by Letters Patent, is

1. In a car-brake in which the brakes are operated from the draw-bar against the resistance of a spring, the combination,with the spring, of a lever operated by a weight imposed on the car to increase the pressure against the wheels of the brakes when set,substantially as described.

2. In a car-brake in which a spring is combined with the sliding draw-bar, and brakes and operates automatically to set the brakes when the draw-bar occupies its normal position, and is operated automatically to effect the release of the brakes by the pulling outward or forcing inward of the draw-bar from its normal position, the combination, with the said spring and with the car-truck supporting the car, of a lever operated by a weight imposed upon the car to increase automatically to the desired extent the pressure of the brakes against the wheels when the said brakes are set, substantially as described.

3. The combination, with a car-brake in which a spring is combined with the sliding draw-bar, and brakes and operates automatically to set the brakes when the draw bar occupies its normal position, and is operated automatically to effect the release of the brakes by the pulling outward or forcing inward of the draw-bar from its normal position, of a bell-crank lever, F, pivoted at its angle to a support on the car and connected at one end with the said operating-spring, and a suitable bearing, I, upon which the other end of the said bell crank lever is adjusted, and which is secured upon a rigid portion of the car-truck, substantially as and for the purpose set forth.

4. An automatic self regulating car-brake comprising, in combination with the sliding draw-bar of a car, the following elements: a lever, B, fulcrumed toward its center at one side of the draw-bar and secured to the draw bar at one end, a lever, O, fulcruined toward its center upon a suitable support, 8, a connecting device, q, connecting the free end of the lever B with one end of the lever O, a connecting device, q, connecting the same end of the lever G with the draw-bar, bel1-crank 1ever F, pivotally secured at its angle to the car, spring E, connected at one end with an arm of

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