US802285A - Fluid-pressure brake. - Google Patents

Description

IINITE STATES PATENT OI I IOE,

FLUID-PRESSURE BRAKE.

Specification of Letters Patent.

Patented Oct. 1 7, 1905.

Application filed November 2, 1903. Serial No. 179,445

To ail n-f'mm/ 7'1: nw/y concern:

Be it known that I, MAURY W. HIBBARD, a citizen of the United States, residing at Ohicage, in the county of Cook and State of Illinois. have invented a new and useful Improvement in Fluid-Pressure Brakes, of which the following is a specification.

This invention relates to improvement in the quick-action triple valves of automatic air-brake systems for railway-trains.

It is in the nature of an improvement upon the construction of the triple valve shown, described, and claimed in aseparate concurrent application for Letters Patent filed by me July 6, 1903, Serial No. 1643M.

My objects are to provide means for protecting the valve actuating flexible diaphragms against undue strain in use, to provide a novel diaphragm actuated slide valve governing the brake-cylinder exhaust-missage, the diaphragm itself operating at the same time to control the feed to the auxiliary reservoir, and, further, to provide other improvements which tend to render the construction particularly compact, durable, and Well adapted for its purpose.

In the accompanying drawings I show my improved valve device in section, fastened in the usual manner against the end of an auxiliary reservoir, the latter and the pipe extending to the brake-cylinder being also shown in section and broken away.

A is the triplewalve body, and BC caps secured thereto, all of which make up the shell of the valve device. The shell has the trainpipe port or passage (t, port or chamber 1), registering with the brake-cylinder pipe I), and ports 0 cl for communication with the auxiliary reservoir E.

F is a piston'chamber having the bushing e and closed by the chambered cap B, presenting a shoulder or annular piston-seat A chamber (I is in open communication at one side with the passage (Z and is separated from the chamber F by a wall g, having a central opening through it, formed with an annular valve-seat y.

H is an emergency-passage extending from the chamber F, where it presents ports It, near the seat 7", to the brakeeylinder passage or chamber 6. Around the opening between the passages Hand 1) is a bushing c, presenting a valve-seat, and in line therewith is an opening between the passage H and chamber G, presenting an annular valve-seat It.

I is a piston device having a back plate l,

the periphery of which slides freely in the bushing e. Fastened to the back plate is a forward plate or disk on, having a central opening 122/ and presenting a central pocket around said opening to receive the end of a graduating spring K, bearing at its opposite end against the cap B.

L is a cylindrical cup-shaped valve sliding in the opening between the chamber G and passage H and formed with a valve-face 4:, fitting the valve-seat f, and with a valve-face I fitting the valve-seat Z:. In the end of the cylindrical valve L is a central service-port a, surrounded by a flaring valve-seat a, and adjacent thereto is an inner enlargement in the cylindrical valve, presenting a shoulder a On the back plate Z of the piston-valve device I is a hollow extension presenting an annular valve-face Z, fitting the seat g, and extending therefrom is a hollow stem I, con structed, as shown, with longitudinally-extending slots and presenting a straight annular portion Z to slide in the hollow valve L and an enlarged head portion Z", movable in the enlarged part of said valve to engage the shoulder 92 as hereinafter described. Oonfined at its annular edge portion between the parts i and Nb of the piston-valve device I is a flexible preferably thin metal disk M, having a central opening through which passes a threaded plug 22. V Fastened against the plug 19 is a hollow stem p, presenting an inner shoulder p and a reduced straight cylindrical part 2", fitting and sliding through the part Z of the stem I.

N is a graduating-valve seating at its end against the valve'seat a. The valve N slides in the guide formed by the part ,1) and has an annular head portion N in the part p, arranged to contact with the shoulder p In the part 1) is a light cushioning-spring N confined between the valve N and plug 7).

On the stem I is an annular shoulder Z, and confined between the said shoulder and the inner end of the valve L is a light valveseating spring If.

The graduating-spring K operates to press the piston-valve device in the backward direction, whereby the valve closes the valveseat or port g. The spring It tends to press the Valve L against the seat Z/ and seat or emergency-port 7:, and the spring N tends to press the grad uating-val ve N against the seat or to close the service-port n. The cushioning-srwing N removes the necessity of a rigid connection between the valve N and IIO diaphragm, which would make it necessaryto employ great care in distancing the seating-faces of the two. The face of the back portion l presents a'bearing-surface Z for the flexible diaphragm M, permitting the latter to withstand any amount of pressure against it from the train-pipe side without danger of strain. The disk on is shaped on its rear side to present a bearing-surface m for the face of the plug p and the entire surface of the diaphragm M when the latter is forced in the forward direction by pressure from the auxiliary reservoir, as hereinafter explained. Thus all danger of undue strain upon the flexible diaphragm M is removed.

In the upper part of the body A is a chamber P, closed by the cap C. Confined between the body A and cap C is a slightly-dished stiff-metal disk having a central opening In the under surface of the cap 0 is a central socket or chamber G, from which extends a cored passage 7' to the piston-chamber F. The passage '1' extends through the bushing 0, opening into the chamber F at the port in the position shown. Confined around its annular edge portion between the cap C and disk 9 is a flexible preferably thin metal diaphragm Q, having a central opening, to which is secured a stem Q, having a recessed downwaI'd-extending arm or hook portion In the bushing e in the position shown is a port a, extending to a valve-chamber R between the chambers F P. In the chamber R at the port a is a valve-seat a and at the lower end of the passage 8, extending from the chamber R to the chamber P, is a valve-seats. 1n the chamber R isa puppet-valve R. seating normally against the valve-seat and in the passage 5' is a puppet-valve R seating in the chamber R normally upward against the valve-seat s. Confined between the valves R R is a light spring R The valve R has a stem R projecting upward into the chamber P.

On the body A, where it fits against the opening E of the auxiliary reservoir, is a valve-face 1, through which extend the port (I, a port t, communicating with the brakecylinder passage-chamber b, and a port 6 communicating with the exhaust chamber or passage S. The ports (Z t f are in vertical line.

T is a slide-valve fitting and sliding upon the seat 2/ and having the chamber 1 and a passage through it, o, in the relative positions shown. The slide-valve is held to its seat by the spring T, the spring in turn pressing and sliding against a stiff plate T forming part of the body A, or fastened independently to the auxiliary reservoir.

In the chamber P is a pivot-pin w, on which is fulcrumed a lever c, extending at one of its arms through the opening 0 and at its other arm passing through the recess in the arm or hook Q and over the path of the stem R of the valve Beyond the opening 0 the leverV is pivotally connected, by means of a link V, to the slide-valve T.

In practice air from the train-pipe enters through the port a, passing through the strainer across the drain-cup B to the chamber F, supplementing the action of the graduating-spring K in pressing the pistonvalve I against the seat g and operating to press the diaphragm M to the seat Z to move the parts carried thereby to the backward position, wherein the graduating-valve N is pressed to its seat by the spring The train-pipe pressure also passes freely through the port?" and passager to the chamber C to bear against the upper surface of the diaphragm Q. As the chamber P is always in open communication with the auxiliary reservoir through the port 0, the under side of the diaphragm Q is subject to all variations of reservoir-pressure. IV hen thelatteris below the pressure of the train-pipe, the diaphragm Q will be forced downward by the train-pipe pressure, causing the lever V at its free end to bear downward upon the valve-stem R* and open the valve R This permits pressure from the chamber F to open the valve R and pass through the port 0, chamber R, and port a to the chamber P and auxiliary reservoir to feed the latter. In the position shown the slide-valve T closes communication between thechamber G and auxiliary reservoir and closes communication between the ports 6' t of the exhaust-passage. Thus in the event that the graduating-valve N does not seat perfectly or should open before movement of the diaphragm Q pressure cannot pass from the auxiliary reservoir to the brake-cylinder until the exhaust-valve is closed. hen the pressure between the trainpipe and auxiliary reservoir balances, the flexible diaphragm Q may assume the central position shown, the lever V being outof contact with the stem of the valve R and the lat ter is closed by its spring R When trainpipe pressure is reduced for a service stop, the then preponderating auxiliary-reservoir pressure raises the diaphragm Q against the seat 11, presented by the cap G. This seat properly limits the rise of the diaphragm and relieves the latter from strain, just as the surface q of the plate q relieves the diaphragm from undue strain when pressed in the downward direction. Rise of the diaphragm Q against the seat a; causes the level-V to move the slidevalve in the downward direction, closing or maintaining closed communication between the ports 25 t of the exhaustpassage and opening the port (Z, whereby the chamber G is opened to the auxiliary reservoir. This reservoir-pressure, being in excess of the reduced train-pipe pressure, causes the diaphragm M to be moved from its seat Z. In this movement the stem p is drawn forward, causing the shoulderp to engage the head N of the valve N and withdraw the latter from its seat a. Pressure from the auxiliary reservoir through the chamber Gr will then pass through the slots Z of the stem 1 to the service-port n and brakecylinder, producing service application of the brakes. When train-pipe pressure is raised to release brakes, the diaphragm Q, as before stated, is lowered to cause the lever 1) to raise the slide-valve to bring about communication between the exhaust-passage ports t t,whereby the air in the brake -cylinder exhausts freely. Following the opening of the exhaust the leverVopens the valve R to bring about feeding of the auxiliary reservoir. Thus it will be seen that the exhaust will be opened before the feed of the auxiliary reservoir commences. WVhen pressure is reduced in the train-pipe to bring about an emergency stop, the operation of the diaphragm Q is the same as in the case of a service stop, but naturally quicker. The sudden great preponderance of auxiliary-reservoir pressure causes the diaphragm M to be first moved to open the service-port a and then the whole piston device to be moved from the seat 9 without the resistance of the emergency-valve to expose the full area of the piston device to auxiliary-reservoir pressure, which overcomes the resistance to movement of the emergency-valve and moves the piston device to the seat f. The first result of this movement is to slide the head portion of the stem Z against the shoulder a to engage the valve L and to then move the valve L from its seat to open the emergency-port Before the piston device reaches the seat f there will be a sudden rush of pressure through the ports /1/ and the emergency-passage H from the train-pipe to the brake-cylinder to effect the serial quick action. When the piston device reaches the seat f, its rear edge uncovers the ports 7e sufficiently to permit the auxiliary-reservoir pressure passing through the chamber G and port 9 to rush through the emergeney-pas sage H to the brake-cylinder in the required time. Thus it will be seen that my improved valve device is arranged to produce the auxiliary-reservoir feeding, service stops, and emergency stops in the manner required by the rules of the Master Car-Builders Assoeiation and performs the said functions with great rapidity and certainty. The construction of the piston-valve device, involving the springs N insures thorough and proper seating of all the valves carried thereby. The construction involving the diaphragm Q, lever P, and slide-valve T and attendant parts is particularly responsive to the variations in pressure between the train-pipe and auxiliary reservoir and certain in its action.

My improved valve device is of a particularly compact, durable, and inexpensive construction, and while I prefer to provide it throughout as shown and described various modifications of details within the spirit of the invention as defined by the claims may be made.

\V hat 1 claim new, and desire to secure by Letters Patent, is

1. In an automatic fluid-pressure brake apparatus having an abutment, movable to open and close thepassage for pressure to the brakecylinder, a valved passage for feeding pressure from the train-pipe to the auxiliary reservoir, and a brake-cylinder exhaust-passage, the combination of a separate movable flexible diaphragm exposed on opposite sides to pressure from the train-pipe and auxiliary reservoir respectively, and a slide-valve governing said exhaust-passage actuated by movement of said flexible diaphragm, under variations of pressure, to open and close said exhaust-passage.

2. In an automatic fluid-pressure brake apparatus having an abutment, movable to open and close the passage for pressure to the brakecylindcr, a valved passage for feeding pressure from the trainpipe to the auxiliary reservoir, and a brake-cylinder exhaust-passage, the combination of a separate movable flexible diaphragl'n, exposed on opposite sides to pressure from the train-pipe and auxiliary reservoir respectively, and a slide-valve, governing said exhaust-passage and the passage of pressure from the auxiliary reservoir to the brake-cylinder, actuated by movement of said flexible diaphragm under variations of pressure to open and close said passages.

3. In an automatic fluid-pressure brake apparatus having an abutment, movable to open and close the passage for pressure to the brakecylinder, at valved passage for feeding pressure from the train-pipe to the auxiliary reservoir, and a brake-cylinder exhaust-passage, the combination of a separate movable flexible diaphragm, exposed on opposite sides to pressure from the train-pipe and auxiliary reservoir respectively, a slide-valve governing said exhaust-passage, and an operatinglever for the slide-valve actuated by movement of said flexible diaphragm.

4. In an automatic fluid-pressure brake apparatus having an abutment, movable to open and close the passage for pressure to the brakecylinder, an auxiliary reservoir-passage for feeding pressure from the train-pipe to the auxiliary reservoir, and a brake-cylinder exhaust-passage. the combination of a separate movable flexible diaphragm exposed on opposite sides to pressure from the train-pipe and auxiliary reservoir I'GSDQChlVOlY, a slide-valve governing said exhaust-passage, an operatinglever for the slide-valve actuated by movement of said flexible diaphragm, and a checkvalve in the said auxiliary-reservoir passage in the path of said lever, substantially as and for the purpose set forth.

5. The combination with a valve, of a movable valve-actuatingflexible diaphragm,a sup- IIO porting-casing therefor having a Wall limiting the movement of the diaphragm in the direction of effecting closingmovementof the valve and against Which the diaphragm seats, under pressure. to be relieved thereby from undue strain and means cooperating With the diaphragm and valve for permitting the diaphragm to move to its seat after the valve is closed.

6. The combination with avalve, of a movable valve-actuatin g flexible diaph ragm,a supporting-casing therefor having Walls at opposite sides of the diaphragm limiting the movement of the diaphragm under pressure from either direction to relieve the diaphragm from undue strain, and means cooperating With the diaphragm and valve for permitting the diaphragm to move to one said Wall in opening the valve and to the other said Wall after the valve is closed.

7. In an automatic fluid-pressure brake apparatus having ports and passages communieating respectively with the train-pipe, auxiliary reservoir and brake-cylinder, the combination of an emergency-valve, a piston device governing said valve, a valve-seating spring interposed betW een said piston device and valve, a graduating-valve and a flexible diaphragm on said piston device and having movement paratus, having ports and passages communieating respectively with the train-pipe, auxiliary reservoir and brake-cylinder, the combination of a chambered emergen cy-valve provided with a service-port, apiston device having a chambered perforate stem operatively engaging said emergency-valve, a diaphragm on said piston dei'ice and having movement independent thereof, a graduating-valve in the chambered emergency-valve governing said service-port, and in the path of said diaphragm to be opened by movement thereof in one direction, and a cushioning-spring interposed between the said diaphragm and graduating-valve, the said piston device and 'diaphragm being exposed on opposite sides to pressure from the train-pipe and auxiliary reservoir, respectively.

M AURY XV. HIBBARD.

In presence of- WVALTER N. TINBERG, W. B. DAVIES.

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