US435019A - Car-brake - Google Patents

Description

(No Model.) 3 SheetsSheet 1. M. B. LEONARD, GAR BRAKE.

No. 435,019. Patented Aug.26,1890.

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(No Model.) 3 Sheets-Sheet 2.

' M. B. LEONARD.

UAR BRAKE.

N0. 435,019. PatentedAug. 26, 1890.

W W mww (No Model.) 3 Sheets-Sheet 3. M. B. LEONARD.

GAR BRAKE.

No. 435,019. Patented Aug. 26, '1890.

- WZJJVESSES I 1/? E 2072 Wit/ %W UNITED STATES PATENT OFFICE.

MICHAEL B. LEONARD, OF RICHMOND, VIRGINIA.

CAR-BRAKE.

SPECIFICATION forming part of Letters :Patent No. 435,019, dated August 26,1890. Application filed January 30, 1890. Serial No. 338,597. (No model.)

T0 at whom it may concern:

Be it known that I, MICHAEL B. LEONARD, a citizen of the United States, residing at Rich mond, in the county of Henrico and State of Virginia, have invented certain new and useful Improvements in Oar-Brakes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same. I

My invention consists in the improved form of brake-gear, hereinafter to be more fully described and claimed.

In the drawings, Figure '1 is a plan view of a car-truck with the brake apparatus applied to one set of wheels. Fig. 2 is a plan view of the brake-rod connections under the car, showing the manner in which one brake-gear may be connected to another to set the brakes on all the wheels. Fig. 3 is a detailed View in section showing the friction portion of the brake-gear. Fig. 4 is a detailed view in section of one of the pistons and piston-rods employed. Fig. 5 is a detailed View of the brake-drum; and Fig. 6 is a detailed View of the yoke through which power is transmitted to the brake mechanism. Figs. 7 and 8 illustrate modifications.

' Throughout the drawings like referenceletters refer to like parts.

There is a well-known class of brake-gears for railwaycars, sometimes called automatic, in which the brakes are applied by the winding up of a chain on a drum turned bythe revolution of the car-axle,thesaid drum being caused to revolve with said axle, when desired, by the operation of some frictional or locking device under control of the brakeman. In' this class of brakes the motion of the car tends to destroy itself, and to that extent the brake-gear is automatic. The disadvantage of the brake -gear heretofore devised to operate upon this principle has been that it will not operate in connection with the common air-brake system, in which the brakes are applied by reducing the pressure of air or compressed fluid in the train-pipe. Attempts have also been made to devise a continuous brake-gear in which the brakes shall be applied by the direct action of springs and let off by the compression of said springs through the medium of compressed air or other fluid from the train-pipe; but the difficulty has been that the distance through which said springs have had to expand in order to take up the wear and elasticity of the brake gear and apply the brakes was so great that no springs of suffioient power would expand to that extent,and for this and other reasons this class of brake-gears, though having many advantages, have not come into general use.

To produce a continuous automatic brakegear .which may be operated by the motion of the ear and be easily controlled either by the engine-driver or the brakeman on the car, which shall be applied by the action of springs and let off by the compression of said springs without necessitating any considerable degree of expansion of said springs, I have designed the apparatus illustrated, in which A is the main beam of acar-truck supported 011 the springs O and the wheels B B in the usual way. Brake-shoes S S are supported on the brake-bars D D in the customary manner. The chain E at one end is attached either directly to the brake-bar D or to a system of levers, hereinafter to be described, which operates on said brake-bar, and at the other end is wound upon the drum V whenever said drum V is caused to revolve with the axle b of the truck-wheel. is attached to the drum by means of the eyebolt w, screwed into the lug IV, as. shown in Fig. 5, or in any other suitable manner. The drum V normally remains stationary and does not revolve with the axle b; but it may be caused to revolve with said axle at any time by means of the apparatus which I will now describe.

On the axle l), as best shown in Fig. 3, is mounted a sleeve, which I have shown made in two parts I I, held in place upon and caused to revolve with the axle by means of the keys 6 2'. Upon this sleeve and held in place by the flanges Y Y are the frictionshoe V", the drum V, the cylinder or nest of cylinders J, and the cap K. It is evident, of course, that the sleeve can be made in one piece it provision be made for slipping the other parts over one end (one flange, as Y, being removed) and then retaining them in place by means of pins or any equivalent de- This chain E provided the lever G, pivoted to the main.

vice. 'v, of. suitable inclination, to. which a corresponding face on the drum V conforms, so that when the drum is forced down upon the friction-shoe it will bind upon the same and rovolve with it, unless withheld by a greater force. The shoe V is attached to and caused to revolve with the sleeve I by means of bolts X, passing through the flange Y, or by equivalent devices. In order to force the drum down upon and thus lock it to the frictionshoe, either at the will of the engine-driver or of the brakeman upon that particular car, the pistons Q Q, controlled by air-pressure and by the springs P P, are used. Each piston Q moves in a cylinder 0 O,and forms an air-tight joint therewith by virtue of the cupped leather packing q, held in place by the washer If, all as shown in Fig. 4. The piston-rod T is screwed into an extension or secondary piston Q, of less diameter than the first piston, and this also is packed in the extension 0 of the cylinder constructed therefor by means of the cupped leather packing q, held in place by the washer t, as shown. In

this way the ordinary stuffing-box is done away with.

In the end of the piston-rod, or in the extension thereof, is set a hardened-steel nipple R, having the hemispherical surface shown, which when the piston Q is forced outward bears against the side of the drum V and forces it upon the shoe V. The object of the nipple R is to form a simple but nearly-frictionless bearing of the piston-rods upon the drum. It may be removed and a new one inserted when worn. The cap K fits over the end of the main cylinder J, and by means of the ring entering a suitable circular opening 7c closes the cylinders O 0 from all ingress of dirt. This cap furnishes a backing for the s rin s P P as shown and when forced in' the direction of the arrow, Fig. 3, compresses the springs and forces the piston out, so that the drum is locked upon the friction-shoe V. In order to set the said cap K over to the right, in the manner above described, I have beam of the truck, as shown in- Fig. 1, and having the circular yoke g formed therein for surrounding the car-axle b. This yoke is perforated at opposite points, as shown in Fig. 6,-

and pivoted to the double lugs Z on the back of the cap K by means of the bolts g, as shown in Figs. 1, 3, and 6. The chain F is attached at one end to the lever G, and passin g around any suitable number of guide-pulleys f is wound upon the Windlass operated by hand-wheel II in the usual way. The closed ends of the cylinders O O are connected by a suitable circular passageway U, through which compressed air or other compressed fluid is supplied from the train-pipe by means of the connection at, as shown in Fig. 3. Thecylinder or nest of cylinders J may of course be supported upon the revolving sleeve 1; but I prefer to support the same The friction-shoe V has a curved face by means of a bracket M, attached to the crossbeam A, as shown in Fig. 1. This bracket M is perforated by the slot on, to permit the passage of the pipe-connection a and of the play of the cylinder J withinthe bracket through a certain space.

The chain E, winding on the drum V, may, as above stated, be attached at one end directly to a brake-bar I), or it may be connected to any suitable system of brake-rods by which all the shoes maybe simultaneously set against the wheels of one car by the operation of anyone of the friction devices. Such an arrangement I have illustrated in Fig. 2 in diagram, and partially in Fig. 1. In this arrangement the chain E is attached to one end of the lever d, which is pivoted to a brake-bar l), and has its other end attached to abrakebar L. The other extremity of L is connected to one end of another lever d, which in the same way is pivoted to a brake-bar D and has its other end attached to the long rod L The other end of the rod L is attached to one end of a similar lever d on the other truck, and the remaining connections for this other truck are similar to those above described. It is evident, therefore, that whenever the hand-wheel H or H is turned, and the frictionapparatus thereby operated, and either of the drums V is caused to revolve, the entire set of levers, rods, bars, and chains above described will be subjected to tension and will cause all the brake-shoes to be set upon all the wheels through the running-gear of the car.

The method of operating my invention is the following: By twisting the hand-wheel H, and thereby winding up the chain F, the lever G is oscillated and forces the cap K toward the right, as shown by the arrow in Fig. 3. This presses the springs P P, forces out the respective piston-rods, and presses the drum V upon the friction-shoe V, thereby causing the drum to lock itself upon the friction-shoe and to revolve therewith. This winds up the chain E and applies the brakes in the manner above described, The handwheel H being locked in position by the usual ratchet, (not shown,) the brakeswould be permanently set if nothing further were done; but by connecting the nipple n with the trainpipe leading to an air pump or tank of compressed air or other fluid on the engine sufficient pressure may be introduced under the pistons Q, by virtue of the distribution of compressed air through the circular passage U, to compress the springs P P still farther, and thereby remove the pressure from the drum V, the result being that the friction-shoe V revolves idly and the brakes are released. Therefore the brakes may be operated from the engine by reducing the pressure or increasing it in the manner customary in airbrake systems. It is evident that this operation would be the same whether the train were composed entirely of cars fitted with air-brake. If at any time a car becomes detached from the train, the rupture of the train-pipe connection will reduce the pressure under the pistons and the springs will instantly apply the brakes. If at any time the brakeman desires to release the brake on any particular car, he can do so independent of the engineer, and without destroying the airconnections, by simply releasing the handwheel H. WVhenever the car is cut off from the train or coupled up in a train which has not the air-brake fitting, the brake may be operated by hand in the usual manner. It is of course understood that various modifications of the brake-rod connections and in the working details of the friction apparatus could be used without departing from the spirit of my invention so long as the principle of operation of the brake is the same as above set out.

The advantages of my improved brake-gear are evident. By giving a proper amount of inclination to the friction-surface of the shoe V a comparatively small pressure on the drum V will cause a heavy pull on the brakechain, and the said pressure can be easily and readily produced by the brakeman, as described. The movement of a sixteenth of an inch of the friction apparatus will apply the brakes with full power, though of course a greater capacity of motion is provided for, and this power may be exerted through any distance without further expansion of the springs simply through the winding of the brakechains. In this way springs of the necessary stiffness maybe used without subjecting them to any considerable degree of expansion and contraction. No matter how much the brakegear bends or wears, the full pressure follows it up to the end. By having the brake applied by spring action the possibility of failure through valves sticking, the leakage of tanks, &c., is avoided. There is no possibility of the brakes leaking off, even if they are set for an indefinite period of time, and but a small amount of compressed fluid is needed to operate the brakes, since the pistons have but a fraction of an inch of travel, therefore relieving the air-pumps of a large percentage of the work necessary with other gears. In short, the brake will operate more quickly,

positively, and powerfully than the direct-act-.

ing air-brake, and can be let off more quickly. The car to which it is attached'may be connected up with cars having the usual form of air-brake and operated in unison therewith. The brakewill be automaticallyapplied on the parting of the train-pipe, and may be released or applied under all circumstances by the brakeman without leaving the car-platform.

Certain of the modified forms of construction which may be employed are illustrated in Figs. 7 and 8. Thus it maybe foundpreferable to form the fulcrum by means of the link G, as shown in Fig. 7, instead of having said fulcrum rigid upon beam A. This would obviate any possibility of the cap K binding on the cylinder J. A stop-chain F may be provided to prevent too ample motion of the cap K, whereby it might become entirely unseated from the cylinder J. It is also a possible and sometimes a preferred construction to have the bracket M cast solid with the cylinder, as at M, Fig. 8. In that case the bracket M would be pivoted at 1V and the cylinder J wouldbe cut away at J to permit of its being swung down over the axle in the required position. The cap K would then preferably be made in two parts bolted together by means of the lugs Kand I It is understood, of course, that with the construction illustratedin Fig. I the cylinder might be made fast in the bracket M without any longitudinal play, and that when such play is provided for it should never be sufficient to permit the face of J to come in contact with the drum V. It is also evident that any num ber of cylinders O 0 may be used. In Fig. 8 four are shown. In the other construction illustrated in the other figures six are provided for; but any convenient number may be used.

Having therefore described my invention, what I claim as new, and desire to protect by Letters Patent, is-

1. In a brake-gear, the combination of the car-axle, the friction-shoe mounted thereon, the drum, one or more cylinders, pistons in the same which have piston-rods that bear against the drum, springs which tend to force said piston rods out and thereby lock the drum upon the friction-shoe, the air-conduit connecting with said air cylinder or cylinders, whereby power may be applied to with draw the piston-rods and unlock the drum from the friction-shoe, the brake-shoes, hrakebar, and chain wound on the drum, substantially as described.

2. In a brake-gear, the combination of the car-axle, the friction-shoe mounted thereon, the drum, one or more cylinders, pistons in the same which have piston-rods that bear against the drum, springs which tend to force said piston-rods out and thereby lock the drum upon the frictionshoe, the air-conduit connecting with said air cylinder or cylinders, whereby power may be applied to withdraw the piston-rods and unlock the drum from the friction-shoe, the brake-shoes, brakebar, and chain wound on the drum, together with the movable cap for the cylinder or cylinders, against which the springs are backed, and the mechanism for moving said. cap operated by hand, substantially as described;

3. In a brake-gear, the combination of the car-axle, the friction-shoe mounted thereon, the drum, one or more cylinders, pistons in the same which have piston-rods that bear against the drum, springs which tend to force the piston-rods out and thereby lock the drum upon the friction-shoe, the air-conduit connecting with said air cylinder or cylinders, whereby power may be applied to withdraw the piston-rods and unlock the drum IIO - from the friction-shoe, the brake-shoes, brakebar, and chain wound on the drum, together with the movable cap for said cylinder or cylinders, against which the springs are backed, the lever pivoted to'the cap, the chain attached thereto, and the hand-wheel, substantially as described.

4. In a brake-gear, the combination of the friction-shoe, the drum, the cylinder, the spring, the piston which moves in said cylinder, and the rounded nipple projecting from the end of the piston-rod and butting against the drum, substantially as described.

5. In a brake-gear, the combination of the friction-shoe on the car-axle, the drum, the piston-rods butting against said drum, the springs which tend to force said piston-rods into contact with the drum, and a lever and connections whereby pressure is applied to friction-shoe on the car-axle, the drum, the

piston-rods butting against said drum, the springs which tend to force said piston-rods into contact with the drum, and a lever and connections whereby pressure is applied to said springs, together with the link pivotally connected to said lever and to the gear-supporting bracket, substantialiy as described.

7. In a brake-gear, the combination of the car-axle and the rotating friction-gear, the cylinder, which has its under portion cut away, so that it may fit down over the caraXle, and the arm cast solid therewith, Whereby it may be pivoted to its support, substantially as described.

In testimony whereof I afiix my signature in presence of two witnesses.

MICHAEL E. LEONARD. Witnesses:

' M. '1. SPIOER,

J. R. DURRET'I.

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