US837358A - Local-application and equalizing valve. - Google Patents

Description

No. 887,358. PATENTED DEC. 4, 1906 W. v. TURNER & n. M. LEWIS. LOCAL APPLICATION AND EQUALIZING VALVE.

APPLICATION FILED 0014, 1902. RENEWED MAR. 24. 1906.

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WITNEESSES" 6m.

FIG. 4;

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ATTOHNEKS TED sTAii s PATENT OFFICE.

VALTER V. TURNER AND DAVID M. LE'WIS, OF'RATON, TERRITORY OF NEW MEXICO, ASSIGNORS TO THE WESTINGHOUSE AIR BRAKE COM- PANY, OF PITSBURG, PENNSYLVANIA, A CORPORATION OF PENN SYLVANIA.

LOCAL-APPLICATION AND E'QUALIZING VALVE.

To all whom it may concern:

Be it known that we, WVALTER- Y. Ti'uxnn and DAVID M. LEWIS, citizens of the Unit ed 1 States, and residents of Baton, Colfax county,

Territory of New Mexico, have invented cer- 1 tain new and useful Improvements n1 Localj Application and Equalizing alves, of which j the following is a specification.

Our invention relates to fluid-pressure rail way-brakes, and more particularly to a localapplication and equalizing valve adapted to be applied to the ordinary form of fluid-pressure railway-brakes, such as the common type of automatic a1r-brakes with which a triple i valve, either with or without quick-action parts, is employed.

Our objects are to provide a valve mechanism of the character indicated by the use of which a local reduction can be secured on each car, thereby securing quicker and more uniform application of the brakes. thus preventing slack of the draft-gear from running in quicker than it can be taken up, obviating an objection which in the prior constructions with which we are familiar has been the cause of frequent damage; to secure a heavy and quick application for emergency service with air from the train-line in addition to the auxiliary air; to secure a uniform brakecylinder pressure irrespcct ivc of piston travel, thereby causing each car to do its own share of the braking action in the train; to

valve which shall comprise the fewest num ber ofparts, arranged in the simplest and most compact manner and capable of ready application to existing and other similarlyconstructed braking mechanisms and adapted to perform the service desired in the most Specification of Letters Patent.

Patented Dec. 4, 1906.

Application filed October 4, 1902. Renewed March 24. 1905 Serial No. 251.847.

l effective manner and which shall embody the. most durable arrangement of parts.

With these objects in View our invention f consists of the novel construction and com bination of parts and details thereof, as hereinafter described, with reference to the accompanying drawings, and more particularly pointed out in the claims.

in the drawings, Figure 1 is a central vertical section on the line 1 1, Fig. 3, with the j piston and valves in elevation. Fig. '2 is a g transverse section on the line 2 2, Fig. 1, with t the valves in elevation. Fig. 3 is a central vertical section on the line 3 3, Fig. 1, with l the piston and valves. in elevation, and Fig. l -t is a top plan view of Fig. 3.

l ,ltel'erring to tie drawings, in \Ylitlt the same reference characters relate to the same v or corresponding parts in all tle views, the l letter A indicates a valve-body wlich is preferably cast in one piece, with cored passages and cavities for ports, conduits, and valve ct ambeis formed therein, tie top of wlich ctianiber is prelcrably closed by a removable cap B. it' l in ttie -i1amber of the valve body or casing A is a movable equalizing abutment or piston L, dividing the casing into two ct ambers, an expansion and equal izing chamber l) below tl1e piston and an expansion-(rsmber 1) above the said piston, tle latter of wt ich is provided with the usual packing-l ing M. .llxtei-iding from the lower tace ol tr e abut ment or piston 11 is a stem N, tlze lower end of wl'icli passes through a close-titling leedway formed in the casing A, and terminates in a beveled lower face, tl' us const it at ing a t rain-line 'reduction-valve 'l, adapted to seat against; a similarly-beveled seat I. Extending from the upper face of tie pist on. 11 is a post O, which acts as a stop in service applical ion by contact with a similar post K, projecting downwardly from the graduating-stem t contined wittin a cage E, carried by a spring-case nut C, screwed in He cap B, tie lower end of said cage being closed by a cap 1, against which a collar H on the graduating-stem G normally tests and acts as a lower stop for said graduating-stem,

fitting opening in tlze cap I, which acts as a guide for said stem. Confined withinthe l cage E is an emergency-spring F, t he upper the latter of wiiclr passes tlrough a closeend of which seats against the cap and the A projection or boss D on the lower face of the nut G acts as the uper stop for the graduating-stem G. Con ed between a fixed part of the structure, such as the cap I and the abutment or piston L, is a graduating-spring P, which. surrounds the project ing post O, the latter acting as a guide therefor. Between the posts 0 and K is a space J, which is so proportioned as-to provide for the proper movement of the piston L for the ordinary service application.

The chamber D above the piston L is connected to the train-pipe by a pipe or conduit L and to the triple valve by a pipe or conduit M and the chamber D is connected. to the auxiliary reservoir by a pipe or conduit N through the medium of a passage or conduit J and a valve cavity or chamber into which the pipe or conduit hi opens. Confined within the chamber or cavity E is an auxiliary admission and check valve A consisting of a double-face valve-body having beveled faces D and B, adapted to seat against correspondingly-beveled seats E and C, and projecting from each side of the valvebody A are ordinary winged guides F and I G from the latter of which. extends a guid- 'ing-post H for a spring 1 confined between one side of the valve and a fixed part of the structure, such as the lower face of the partition wall between the chamber D and the valve-cavity.

' The chamber D is connected with the chamber D by means of a passage or conduit Q, forming aby-pass around the abutment or piston L, one end of which communicates, through aport Q, with the chamber D and the other end wit-h the space surrounding the lower end of the stem N, so that in the position shown in the drawings the flow is first through the port Q, thence through Q past the stem :N and into the chamber D, and under certain conditions hereinafter described when the valve T is in its extreme open posi tion the chamber D is connected with the passage or conduit Q by means. of a feed groove or conduit R, formed in the side of the stem N, the said feed groove or conduit under the ordinary conditions of operation, such as in service applications, being out of register with the chamber D, but in emergency application being in register therewith. To provide a suitable communication between the space in the lower end of the conduit or passage Q and the brake-cylinder, the reduction-valve T controls a passage or conduit V, which connects the conduit Q with a con duit or passage W, communicating with a valve-cavity Z, preferably formedin the side of a valve-body A transverse to the an of the same. When, therefore, the valve is raised from its seat, it will be observed that tree communication is. established between the passage Q, the passage V, the passage W, and the valve cavity or chamber Z, the latter of which is in communication with the brake-.

cylinder by means of a pipe or conduit C Operating within the cavity Z is a pistonvalve W connected to its operating-piston Y by a stem, such piston being provided with the usual packing-ring Z The valve W is preferably of disk form, having a beveled face seated against the beveled seat X (see Fig. 2,) and the chamber Z is in communication with the chamber D by means of a suitable port or passage X opening into the said chamber above the valve W. chamber Z is closed at each end by caps P and C from the former of which extends a stop Q which limits the upward movement of the valve W and extending from the lower side of the piston Y is a post or stop 0 which when the valve W is seated, as shown in Fig. 2, is adapted to contact with the upper face of the brake-cylindercheck-valve A, whose beveled face A is adapted to seat against a correspondingly-beveled seat A when moved toward said seat, thereby shutting off communication between the brakecylinder and the piston-valve cavity. Se-

cured to or forming part of the check-valve- A is a tight-fitting collar B, between which and the nut C is confined a spring B guided by a. stem B extending from the lower face of the valve A and working in a guiding-recess C and in said cap C. This check-valve is so arranged that under a certain predetermined pressure when a predetermined reduction. of pressure is attained in the expansionchamber, which is communicated through the various connecting conduits or passages to the chamber Z, the said valve will. be moved by the spring B and the airconfinied between the cap C and the collar B, thereby seating the valve against its seat A and The cutting off the brake-cylinder, so as to pre- Y the lowerface ot which'is beveled to fit the.

correspondingly-beveled seat, from the other face of which valve extends the stem U the end ofwhich operates in. a guiding-recess V tormedin' the nut Y, closing the valve-cham.

ber andaround this stem is a spring T confined'betweenafixed part, as. the nut, and-the is connected to the conduit Q by the passage or conduit X, the conduits X and X thus beingion opposite sides of the-disk valve R The parts shown in. the drawings are in the positions. assumed when air has. been sup-- plied to the train pi'p'e in the usual'manner.

to seat an emergency GX,

' valve R The chamber of this exhaust-valve 4 y 1 2 5 To effect this, the air enters the train-pipe in the usual way, passes from the pipe L into the chamber D through the same to the triple valve by way of the pipe M and consequent] y charges the auxiliary reservoir under each car in the ordinary way. At the same time air also passes through the port Q into the conduit Q and upwardly through what may be termed a leak-passage formed between the close-fitting stem N and the feedway S into the equalizing-chamber D and from the latter through the passage X into the space above the valve W and when the latter is slightly opened pressure is exerted against the piston 1' and forces the same downward, causing the valve \V" to close against its seat. Air also passes from the chamber D through the passage J ,-holding the valve A close against its lower seat (7*, thereby charging the vari us parts to standard pressure of, say, seventy pounds. With the parts in the positions thus attained, when an application, as in service, is made by a reduction of train-line pressure the pressure in the chamber D above the abutment or piston L falls more rapidly than it does in the chamber D, and consequently the abutmentor piston L is caused to,1nove upwardly, thereby unseating the train-line reductionvalve T and openingconnnumcation between the conduit Q and the conduit W. This action permits a train-line reduction to take place through the passages indicated by way of the valve-cavity Z past the valve A through the pipe (1 to the brake-cylinder, such action taking place'vcry gradually by the valve A, and consequently the move-' ment of the triple piston is locally assisted, thereby causing the brakes to apply in service more quickly than the slack of the draft-gear can be run in. The expansion-chamber pressure thus attained in the chamber D is, it will be observed, maintained by air from the auxiliary reservoir or other separate expansion-chamber, if desired, such air from the auxiliary reservoir [lowing past the valve A until the auxiliary pressure falls by reduction to the brakecyl inder, and air likewise feeds back slowly to the train-line past the stem N through the passage Q and chamber D When equalization takes place between the train-line and the chamber D, or slightly before this occurs, the abutment or piston L will be forced downward by the spring P, thereby causing the valve '1 to close against its seat, which action occurs about theftime that the exhaust ceases at the engineers valve, thereby stopping the train-line reduction and permittiug the triple valve to'go to lap position, such graduated application being repeated as often as desired until equalization takes place under all the ears. It will be observed that in the movement of the abutment or piston L upwardly the stop K and the spring F when the projection or post 0 comes in contact with said stop prevents further upward movement of the piston in ordinary service application. When, however, an emergency application or reduction is made, the air is suddenly drawn from the train-pipe in large volume, and consequently from the chamber D above the abutment or piston L, and therefore greater excess of pressure in the chamber D causes the abutment or piston L to move suddenly and to forcibly strike the stop K, moving the stem N upwardly to an extent, determined by the amount of reduction. This action causes the reduction-valve T to be raised higher from its seat and permits the train-line air to low in large volume to the brake-cylinder port V, the passage or conduit W, past the check-valve A to the brake-cylinder. When the abutment or piston L lifts to this height, the feed groove or conduit R is brought into direct connection with the chamber D, the upper end registering with the chamber and the lower end with the space around the reduction-valve T, and consequently the pressure in the chamber D is rapidly reduced to that of the train-line, whereupon the springs F and P force the abutment or piston L duwnwardly, thereby seating the valve T, thus preventing air from feeding back from the brake-cylinder to the train-line. With the pressure thus confined in the chamber D it is evident that if some means were not provided for emptying the chamber D of pres sure as the train-line continued to reduce, as in the emergency application or in the event of the train breaking in two, thereby causing a sudden reduction, such expansion-chamber pressure would again raise the abutment or piston L, and thereby permit the brake-cylinder to feed back to the train-line, and therefore to release thebrakes, and to prevent this occurrence the spring B under the checkvalve A, acting in conjunction with the pressure confined below the valve by the close lit of the same and the pressure on the under side of the piston Y raises the valve W as soon as the brake-cylinder pressure reaches that of the train-line, and thereby permits the air remaining in the chamber D to pass through the conduit X to the valve it", and as the pressure on thetrain-line side of this valve is less than that created in the passage or conduit X the valve It is raised from its seat, thereby affording exhaust for the chamber D through the conduit or passage X', the conduit or passage Q, the chamber I), and thence to the train-line, and at the same time the higher auxiliary pressure forces the valve A to its seat, thereby preventing auxiliary pressure going back to the train-line. By this means both the auxiliary IIC pressure and the brake-cylinder pressure are in i triple, removing the present quick-action parts. The desired release of the brakes is accomplished in the usual mannernamely, by the engineer increasing the train-line pressure-though much more uniformly than at present, as it is evident that if there is a tendency on any brake on account of unequal piston travel vto equalize higher than the required fifty pounds with twenty pounds reduction as the valve T is raised the pressure from the brake-cylinder and auxiliary reservoir will flow back to the train-line, and thence to the other brake-cylinders, where the pressure is loweron account of longer piston travel. Thus when equalization is attained by, say, a twenty-pound reduction all the auxiliaries will be of an equal pressure, which uniform pressure permits a uniform release of the brakes.

While we have used the terms upper and lower, upwardly and down- Wardly in this specification, it is to be understood that such terms and those of a similar import are employed both in the description and claims merely for convenience and are not words of limitation, but only descriptive, since it is obvious that the valve structure may be employed in any suitable position, and, furthermore, the term abutment or piston is intended to cover the generic form of this element, whether diaphragm or iston, while the term air is likewise used or the sake of brevity in a similar manner and with the same legal eiiect, it being understood that our invention applies to any form of fluid-pressure railway braking mechanisms to which it is adapted, as will. be readily understood by those skilled in the art, that form in which the fluid-pressure is created by theuse of compressed air being a common t e in use.

-t will be further observed from the foregoing descri tion that the movable abutment controls .the feed-passage between the conduit or by-pass Q, leading from the first or upper chamber around said abutment and the second or lower expansion and equalizing chamber, said passage being normally restricted, owing to the tight fit of the abutment-stem and enlarged by the groove when abnormal reduction takes place in the trainline, and that all the parts cooperate efliciently to permit local reduction in the trainline to effect service application or sudden or abnormal local reduction in-the train-line to effect emergency a plication, such actions occurring locally un er, each car, and the service application locally assisting in the triple, valve movement, while repeated applications readily secure equalization, so as to permit uniform release of the brakes when desired.

l/Ve claim as our invention 1. In a fluid-pressure railway-brake mech 'anism, the combination of a casing, a movable abutment dividing said casing into two chambers, one communicating with the train-line and the triple valve, a valve-controlled conduit leading from-the other chamber'to the auxiliary reservoir, a conduit con necting the first chamber with the brake-cylinder, and a valve operated by the movable abutment controlling said conduit, substantially as described. I

2. In a fluid-pressure railway-brake mechanism, the combination of a casing, a movable abutment exposed totrain-line pressure on one side thereof anda normally restricted leak-passage for the flow of fluid from said side of the abutment to the other,'a by-pass around the abutment and communicating with the brake-cylinder in service as well as emergency applications, a valve operated by the abutment controlling said assage, and a. valve-controlled passage lea ng from the casing to the auxiliary reservoir, substantially as described.

3. In a fluid-pressure railway-brake mechamsm, the combinationof a casing, a movable abutment dividing said casing into two chambers, one communicating with the train-line and the triple valve, aconduit connecting said chamber with the brake-cylin der, a valve operated by the movable abutment controlling said conduit, and a feedpassage between said latterconduit and theother chamber controlled by the movable abutment, substantially as described.

4. In a fluid-pressure railway-brake mechanism, the com ination of a casing communieating with the train-line and triple valve, a conduit adapted to connect said casing with the brake-cylinder, and valve mechanism operated by a reduction or" train-line pressure, whereby local reduction may be effect ed to the brake-cylinder, thereby locally assisting in the movements of the triple valve, substantially as described.

5. In a fluid-pressure railway-brake mechanism, the combination of a casing, a movable abutment therein dividing said casing into two expansion and equalizing chambers, one of which is in communication with the train-. line and triple valve, a by-pass around said abutment connecting said latter chamber with the brake-cylinder, a restricted leakpas'sage from said condult to the other chamber, and a valve operated by the movable abutment for controlling the flow of fluid through said conduit, substantially as described.

6. In a fluid-pressure railway-brake mechanism, the combinat IOIl of a casing connnuincating with the train-line and the triple 'alve structure and brake-cylinder, mechanism in said casing controlled by local reduction ot pressure in the tram'-line for causing said train-line reduction to occur locally and be i transmitted to the brake-cylinder thereby locally assisting in the movement of the triple casing communicating with the brake-cylinl der, and valve mechanism operating in said casing and controlled by the variations in pressure in the train-line to cause a local reduction from the train-line through the casing to the brake-cylinder, substantially as described.

8. In a fluid-pressure railway-brake mechanism, the combination of a casing interposed in the train-line leading to the triple-valve structure and through which train-line pressure is transmitted, said casing eommunicat ing with the brake-cylinder, valve mechanism in said casing controlled by variations in pressure in the train-line to cause a local reduction of pressure from the train-line to the brake-cylinder, thereby locally assisting the triple-valve movement, means for permitting an emergency movement of said valve mechanism upon sudden and abnormal reduction in the train-line, and a brake-cylinder valve operating to close communication between the brake-cylinder and the casing upon said reduction to prevent return of pres sure from the brake-cylinder, substantially as described.

9. In a fluid-pressure railway-brake mechanism, the combination with the train-line, triple valve and brake-cylinder, of a local application and equalizing valve mechanism operated by a reduction of train-line pre sure in service, as well as emergency, a phcation to permit local reduction from the train-line to the brake-cylinder, thereby locally assisting the movement of the triple valve, substantially as described.

10. In a fluid-pressure railway-brake mechanism, the combination of a casing communicating with the train-line and triple-valve structure, conduits connecting said casing with the brake-cylinder, valve mechanism operated by a reduction of train-line pressure to permit a local reduction from the trainline to the brake-cylinder, a brake-cylinder check-valve controlling the conduit to the brake-cylinder and adapted to prevent return of fluid-pressure from the brake-cylinder when a sudden reduction occurs, but normally open for service application, substantially as described.

1 1. In a fluid-pressure railway-brake mechanism, the combination of a casing communicating with the train-line and triple-valve structure, conduits connecting said casing with the br:Una-cylinder, valve mechanism operated by a reduction of train-line pressure to permit a local reduction from the trainline to the brake-cylinder, a brake-cylinder check-valve cont-rolling the conduit to the brake-cylinder and adapted to prevent return of fluid-pressure from the brake-cylinder when a sudden reduction occurs, but normally open for service application, and an emergency exhaust-valve normally closed in service application, but automatically operated to permit flow of pressure to the trainline after a sudden or emergency application, substantially as described.

12. In a fluid-pressure railway-brake mechanism, the combination of a casing communieating with the train-line and the triple-valve structure, conduits leading from the casing to the auxiliary reservoir and to the brakecylinder, check-valves in each conduit, valve mechanism operated by a reduction of trainline pressure to permit reduction to the brake-cylinder, and an emergency-valve mechanism operated by a sudden reduction or emergency application, a conduit normally closed by said valve communicating with the train-line, and an emergency exhaust-valve in said conduit, substantially as described.

13. In a fluid-pressure railway-brake mechanism, the combination of a casing, a movable abutment dividing the casing into two chambers, one connected to the train-line and triple-valve structure, and the other to the brakc-cylinder, a conduit connecting the first chamber with the brake-cylinder, a restricted feedway between the second chambar and said conduit, a reduction-valve operated by the abutment normally closing the conduit between the first chamber and the brake-cylinder, whereby local reduction in the train-line causes the abutment to move and operate the reduction-valve, substantially as described.

14. In a fluid-pressure railway-brake mech- .anism, the combination of a casing, a movable abutment dividing the casing into two chambers, one connected to the train-line and triple-valve structure, a conduit connecting the first chamber with the brake-cylinder, a restricted feedway between the second chamber and said conduit, a reduction-valve operated by the abutment normally closing the conduit between the first chamber and the brake-cylinder, a normally closed emergency reduction-valve in said conduit between the first valve and the brake-cylinder,

and means for opening said valve when a sudden reduction occurs in the train-line, substantially as described.

1 In a fluid-pressure railway-brake mechanism, the combination of a casing, a. movable abutment dividing the casing into two chambers, one connected to the train-line and triple-valve structure, a conduit connecting the first chamber with the brake-cylinder, a restricted feedway between the second chamber and said conduit, a reduction-valve operated by the conduit between the first chamber and the brake-cylinder, a normally closed emergency reduction-valve in said conduit be tween the first valve and the brake-cylinder, a normally open brake-cylinder check-valve in said conduit, and means for causing said valve to close and at the same time open the emergency reductionevalve', substantially as described.

1 6. In a fluid pressure railway-brake mechanism, the combination of a casing, a movable abutment dividing the easing into two chambers, one connected to the train-line and triple-valve structure, a conduit connecting' the first chamber with the brake-cylinder, a restricted feedway between the second chamber and said conduit, a reduction-valve 0 erated'by the abutment normally closing t e conduit between the first chamber and the brake-cylinder, a normally closed emergency reduction-valve in said conduit between the first valve and the brake-cylinder, a normally open brake-cylinder check-valve on said conduit, means for causing said valve to close and at the same time open the emergency reduction-valve, and a valve-controlled conduit between the second chamber and the train-line normally closed by its valve, but opened thereby upon a sudden reduction, substantially as described.

1 7 In a fluid-pressure railway-brake mechanism, the combination of a casing, a movable abutment dividing said casing into two chambers, one open to the train-line and triple-valve structure, a by-pass around the abutment, a feedway between the second chamber and the by-pass, a stem on the abutment closely. fitting said feedway and termimating in a valve, a conduit connecting the by-pass with the brake-cylinder and normally closed by said valve, substantially as described.

1 8. In a fluid-pressure railway-brake mechanism, the combination of-a casing, a springpressed movable abutment dividing the casing into two chambers, one open to the trainline and triple-valve structure, a by-pass around said abutment, a feedway between the second chamber and said by-pass, a stem carried by the abutment closely fitting said feedway and terminating in a valve, a con- 6 5 1 9. in a-fiuid-pressure railway-brake mach? the abutment normally closing duit normally closed by. said valx ommunies'asee anism, the combination of a casing, a springpressed movable abutment dividing the cats ing into two chambers, one open to the train line and triple-valve structure, a by-pass around said abutment, a feedway between the second chamber and said by-pass, a stem carried by the abutment closely fitting said feedway and terminating in a valve, a con duit normally closed by said valve connnunicarting with the brake-cylinder, an emergency reduction-conduit between the second chamber and the train-line, an emergency reduction-valve normally closing the said conduit, and a graduating-stem acting as a stop for the abutment in service application, but movable thereby when sudden reduction occurs in the first chamber from the trainline, substantially as described.

20. In a fluid-pressure railway-brake mechanism, the combination of a casing, a springpressed movable abutment dividing the cas ing into two chambers, one open to the trainline and triplewalve structure, a bypass around said abutment, a feedway between the second chamber and said by-pass, a stem carried by the abutment closely fitting said feedway and terminating in a, valve, a conduit normally closed by said valve communi eating with the brake-cylinder, a feed-pas-. sage connecting the second chamber with the by-pass normally closed by the stem, but opened by movement of the stem upon sudden reduction in the train-line, substantially as described.

21 In a fluid-pressure railway-brake mechanism, the combination of a casing, a springpressed movable abutment dividing the cusing into two chambers, one open to the trainline and triple-valve structure, a bypass around said abutment, a feedway between the second chamber and said by-pass, a stem carried by the abutment closely fitting said feedway and terminating in a valve, a 'con duit normally closed by said valve comnmnieating with the brake-cylinder, a feed-passage connecting the second chamber with the by-pass normally closed by the stem, but opened by movement of the stem upon sud: den reduction in the trainline, a passage connecting the second chamber with the train line, an emergency reduction-valve normally closing the passage, substantially as dc scribed.

, 22 In a fluid-pressure railway-brake mechanism, the combination ofa casing, a springpressed movable abutment dividing the casing into two chambers, one open to the trainline and triple-valve structure, a by-pass around said abutment, a feedway between the second chamber and said by-pass, a stem carried by the abutment closely fitting said feedway and terminating in a valve, a con duit normally closed .by said valve commumeeting with the brake-cylinder, a feed-pea sage connecting the second chamber with the by-pass normally closed bythe stem, but opened by movement of the stem upon sudden reduction in the train-line, a passage connecting the second chamber with the train-line, an emergency reduction-valve normally closin the passage, and a reduction exhaustvalve in said conduit adapted to be opened by pressure in said conduit in excess of the train-line pressure when a sudden reduction is made, substantially as described.

23. In a fluid-pressure railway-brake mechanism, the combination of a casing, a springpressed movable abutment dividing the casmg into two chambers, one open to the trainline and triple-valve structure, a by-pass around said abutment, a feedway between the second chamber and said by-pass, a stem carried by the abutment closely fitting said teedway and terminating in a valve, a conduit normally closed by said valve communiden reduction in the train-line, a

eating with the brake-cylinder, a feed-passage connecting the second chamber with the by-pa'ss normally closed by the stem, but opened by movement of the stem upon sudassage connecting the second chamber with the train-line, an emergency reduction-valve normally closing the passage, a reduction exhaust-valve in said conduit adapted to be opened by pressure in said conduit in excess of the train-line pressure when a sudden reduction is made, a conduit connecting the second chamber with an auxiliary reservoir, and a valve for closing said conduit to prevent return ofipressure from said auxiliary reservoir when a sudden reduction is made, substantially as described,

24. In a fiuidressure railway-brake mechanism, the com ination of a casing, a movable abutment dividing said easing into two chambers, one communicating with the trainline and triple-valve structure, valve mechgency reduction, piston-valve normally closing communication between the valve-chamber and the second chamber of the casing and having a projecting stem, and a normally closed brake-cylinder check-valve adapted in its closing movement to strike the said stem and open the emergency reductionvalve when sudden reduction is made, substantially as described.

25. In a fluid-pressure brake, the combination with a tram-pi e, auxiliary reservoir, triple valve and bralie-cylinder, of a valve device comprising a movable abutment subject to the opposing pressures of the trainpipe and auxiliary reservoir, and a valve 0perated by said abutment for controllin communication from the train-pipe to the brakecylinder.

26. In a fluid-pressure brake, the combination with a tram-pi e, auxiliary reservoir, triple valve and bralie-cylinder, of a valve device comprising an equalizing chamber, a piston subject to the opposing pressures of the chamber and the tram-pipe, a valve 0 erated by said piston for controlling a local WALTER v. TURNER. DAVID -M. LEWIS.

Witnesses:

JOHN JoERNs, C. A. WYHUS.

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