US2009841A - Fluid pressure brake - Google Patents

Description

HmEy 3Q, M35. E. E, HEWITT 99,841

FLUID PRESSURE BRAKE Filed June 30, 1954 'o' Sheets-Sheet l www lINVENTOR ELLIS EJ-IEWIT T A TT ORN July 30, 1935. E. E. HEWITT FLUID PRESSURE BRAKE `5 Sheets-Sheet 2 Filed June 50, 1934 Imm Sm. mm1

i MM

mill" Hw uw" w 1m INVENTOR I ELLIS EHEvvI-r-r BY Q ATTORN v July 30, 1935. E. E. HEwlT-r 2,009,841

FLUID PRESSURE BRAKE Filed June 30, 1954 3 Sheets-Sheet 3 Figo-Z AUX. R Eqs l I8 17,: :Ill :6

INVENTOR ELLIS E. HEWIT-l' A TTORN Y Patented July 30, 1935 "UNiTEo STATES FLUID PRESSURE BRAKE Ellis E.. Hewitt, Edgewood, Pa., assignor to The Westmghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application June 30, 1934, Serial No. 733,181

43 Claims.

This invention relates to locomotive iiuid pressure brake equipments and more particularly to that type of equipment which includes a distributing valve device such as is fully disclosed in the application of Clyde C. Farmer and myself, Serial No. 619,052, filed June 24, 1932, or inthe application of Charles H. McKinstry, Serial No. 690,685, filed September 23, 1933. l

The former standard fluidA pressure brake equipment for locomotive and cars was designed for handling a train of a length up to around eighty cars. In recent years, however, trains of more than eighty Vcars have been operated on various railroads.

As a consequence of the'increased length of trains, it has become increasingly difficult to properly control the application and release of the brakes and especially to so control an application of the train brakes as to insure the gentle gathering or closing of the slack in the train.

It is Well known that, with this type of equipment, when the engineers brake valve device is turned to either service or emergency position, the brakes apply serially from the front of the train toward the rear of the train, that is to say, the locomotive brakes Will apply iirstandrthen the brakes on the cars will apply serially toward the rear end of the train. As a result of this serial brake action, the deceleration of the locomotive 30 begins before the brakes on the cars'become effective. Y

There is a certain amount of slack or lost mo'- tion in the usual coupling mechanisms between the adjacent ends of adjacentcars of the train, Vand by reason of the fact, as above explained, that the locomotive begins to decelerate' before the cars, this slack will permit'thecars to run in against the slower moving locomotive, thus `the locomotive will contribute to the harsh gathering or closing of the slack in the train.

It is very desirable to avoid the above described slack gathering or closing action when an application of the brakes is initiated, and to obtain this result, means such as is disclosed in the afore- "mentioned prior pending application `of Clyde C. Farmer and myself, SerialNo. 619,652 have been employed for synchronizing vthe application of the locomotive and car brakes, in other wordsr for causing the locomotive brakes to apply at substantially'the same time as the car brakes begin to apply effective braking force. This of course requires the delaying of the application of the locomotive'brakes for a short period of time following the initiation of a brake pipe reduction.

i In the pendingapplication just referred to, Se-

rial No. 619,052, the delay of the application of the locomotive brakes is accomplished by delaying 'the movement of the equalizing portion of the locomotive distributing valve device to service application position and this delay is accomplished by reducing the pressure in the pressure chamber of the device; This reduction is effected by venting fluid under pressure from the pressure chamber to a reduction reservoir or chamber when the equalizing portionhas moved a short distance toward application position upon the reduction in brake pipe pressure, the slide valves of the device establishing the communication through which fluid is vented from the pressure chamber. the pressure chamber, sayV for instance around four or five pounds, has been effected, a cut-off valve subject to the pressure of iluid in the reduction chamber operates to cut offv the flow of uid from the pressure chamber to the reduction chamber, thus limiting the reduction to a chosen degree. Nowr when the brake pipe pressure re- After a reduction in the pressure Vof duces suiiiciently below the reduced pressure in the pressurechamber to create a suflicient fluid pressure differential on the piston of the equalizing portion ,to'causethe piston and associated slide valves to move to application position, an application of the locomotive brakesris effected.

While the'above described `distributing valve device does function to produce the desired synchronizaticnof the application of the locomotive brakes with the application of the car brakes in the desired manner', it has been found in some instances, where. certain manufacturing. inaccuracies exist in the device, the resistance offered by the several movable parts tomovement to service application position is considerably'in eX- ces's of that intendedand that, asa consequence, an excessive reduction in brake pipe pressure is. required to Vcreate a suflicient fluid pressure differential on the equalizing piston to cause it to operate to shift the equalizing slide valves to service application position. It Willhere be understood that the equalizing piston is intended to move the equalizing slide Valves from the pressure chamber venting position when the brake pipe pressure has been reduced sufficiently" to create a fluid pressure differential of aboutY one and one-half pounds on the equalizing piston, Whereas, in a device embodying the above mentioned inaccuracies, the required fluid pressure differential may be as great as four or five pounds, and as a consequence of this, the application of the locomotive brakes Will be unduly delayed, so that the car brakes will apply with an effective braking force before the locomotive brakes apply. This will permit the locomotive to move forwardly relative to the braked cars and cause run out shocks which may be severe enough to break or otherwise damage either the coupling mechanism betvveenthe locomotive and cars or the coupling mechanism between cars at the head end of the train.

One object of the present invention is to provide an improved locomotive uid pressure brake equipment which Will function to provide the desired synchronization of the locomotive brakes with those on the cars of a train andryet .be free of the aforementioned difficulties.

Another object of the invention is to provide' a distributing valve device of the type disclosed in the aforementioned pending application Serial No. 619,052 having improved 'means for delaying the start of a service application of thelocomotive brakes in which the equalizing portion of the device is caused to vmove :to application position upon the initiation of a reductionin brake pipel pressure, toestablishv a communication' through ywhich fluid under pressure is ventedfrom the pressurei chamber tothe reduction chamber by Way ofthe reduction limitingvalve mechanism, and invwhichY the reduction limiting valve mechanism responds to a chosen reduction' chamber pressure to closeA off the iiow of fluid to the reduction chamber to limit thereduction in pressure chamber pressure to a chosen degree, and to then establish a communication throughA which uid under pressure ows fromthe pressure chambeirto theV application chamber and application piston-chamber to cause theapplication portion to supply fluidunder pressure tothe locomotive brake cylinders.

The fundamentaldilferences between theholdbackfeature of the equipment of the present-*application andthat ofthe aforementioned.pendingV application Serial No. 619,052, are as follows: in

the present Aequipment the reduction in pressure` chamber pressure isY e'ectedwhen the equalizing;Y

portion of thedistributing valve .device is moved to service application positio-n'and the supplyof fluid lfor actuating Ythe application :portion to tion-retards. the movement of the equalizing porsupply fluid underpressure 1 to the locomotive brake cylindersis controlledv by the reduction limiting and control valve mechanism and by the equalizing portion. pending application `thereduction in pressure chamber pressure is effected When the equalizing portion is moved'to a position between releaseV position and service applicationposition. `and the supply of fluidfor actuating the application portion to supply fluidlmder'pressure to the brake cylinders is controlled by the equalizing portion only.

It will be understood that when the equalizing portion of the latterl equipment is in pressure chamber venting position, the pressure of iiuid in said chamber is reduced the desired amount,.

(about five pounds). A corresponding reduction in brake pipe pressure will only balancethe pressures on opposite sides ofthe equalizing piston,

so that the equalizing portion will remain in this venting'position until a sufiicient iiuid pressure differential is created to movev itv to service application position. If the fluid pressure diiferential rrequired to move the equalizing portion'to service application position is four `poundsythenit .Will require a further reduction in brake pipe pressure of 'at least four pounds' to create such differential. It will thusbe seen that a reduction in brake pipe pressure of approximately'- nine In the. equipment of said..

pounds is required to cause the equalizing portion to move to service application position in which the equalizing portion supplies iiuid under pressure from the pressure chamber to the application piston chamber to cause the application portion to function to supply fluid under pressure to the locomotive brake cylinders.

In the equipment of the present application, if the-resistance offered by the several movable parts of the equalizing portion is the same as that offered by the corresponding parts of the equipment just referred to in the preceding paragraph, the equalizing portion will move to service application position upon a four or ve pound reduction in brake pipepressure and in this position effects the reduction in pressure chamber pressure and establishes a communication through Whichfluid under pressure is adapted to be supvplied to the application piston chamber of the pressure of the reduction reservoir to close off .the flovv of uid Vfromthe pressure chamber to f the reduction chamber, and at substantially the same time; opens the vcommunication from the pressure .chamber to the application pistoir chamber and fluid supplied through this com-V munication, causes the application portion to function to supply fluid under pressure to thev ylocomotive brake cylinders.

Fromther above comparison it is obvious thatr since the reduction in pressure chamber pressure in the present equipment is not effecteduntil the equalizing portion has been moved to service I application. position, .the equalizing portion will move to this positionupon a much lighter reduction in brake pipe pressure than is required in i the equipment of the pending application where they reduction in pressure chamber pressure is Y effected before the equalizing portion is moved to service application position and Where this reductionto application position. Thus in the equipment of the present application, an undue delay of a service application of the locomotive brakes is avoided.

In effectingfan emergency application of the brakes the service application hold-back means offthe equipment. of the present application and of .the v.equipment of the aforementioned pending application Serial No. 619,052 is ineffective tomaterially delay the-application of the locomotive brakes,and since it is highly desirable to avoid theharsh run in of the slack in the train when an emergency application of. the brakes is effected some means must be provided for preventing such action. Y

To obtainthis result means have heretofore been proposed for'holding back the application of l the locomotive brakes for a period of time after a reduction in brake pipe pressure is initiated, so

that, duringthe period of time that the slack in the train is gathering or closing, the inertia of the locomotive will tend to keep the slack stretched out.

As disclosed inV theaforementioned pending application of Charles H. McKinstry, Serial No. 690,'685,. means have also been proposed which, when an emergency reduction in brake pipe pressure :is initiated, socontrols the rate of increase in the locomotive brake cylinder pressure `that it will not'exceed the rate of increase in brake cylinder pressure on the cars of the train. On a `short train where the traint-slack is not very great and its rapid gathering or closing will not cause damaging shocks, the proposed brake cylinder build up controlling means vmay be rendered ineffective, and to do this, manually operable means has been shown in said pending application.

The brake cylinder pressure build-up control means disclosed in the above mentioned application of Charles E. McKins'try Yis embodied in the equipment disclosed in the present application, and another object of the invention is to provide pneumatically controlled means for rendering the brake cylinder pressure build-upfcontrolA means'v either effective or ineffective to control the rate of increase in locomotive brake cylinder pressure,

and a further feature resides in the provision of manually operable means readily accessible to the engineer for controlling the operation of the pneumatically controlled means to selectively render the brake cylinder pressure build-up con- `trol means effective or ineffective.

Other objects and advantages will appear in the following more detailed description of the invention.

In the accompanying drawings, Fig. 1 is a diagrammatic view, partly in section, of a locomotive iiuid pressure brake equipment embodying the invention; Fig. 2 is an enlarged diagrammatic sectional View of the distributing valve device, the several parts being shown in release position; Fig. 3 is a fragmentary diagrammatic sectional view of the distributing valve device showing the equalizing portion in service application position and the reduction limiting and control valve mechanism in its pressure chamber venting position; Fig. 4 is a fragmentary `diagrammatic sectional view showing the reduction limiting and control valve mechanism in service application position; Fig. 5 is a fragmentary diagrammatic sectional view showing the equalizing portion of the distributing valve device in emergency application position; Fig. 6 is a developmen't View of the automatic brake valve device; and Fig. 7 is a diagrammatic view of a train consisting of a locomotive, tender and two cars.

As shown in Fig. l of the drawings, the locomotive fluid pressure brake equipment may comprise a main reservoir l, a feed valve device 2, an automatic brake valve device 3, an independent brake valve device 5i, a brake pipe 5, a distributing valve device 5, a brake cylinder 1, an emergency change-over brake cylinder pressure build-up control valve device 8, anda manually operable valve device 9 for controlling the operation of4 the control valve device 8.

The distributing valve device S, with the exceptions whichare hereinafter particularly pointed out, is substantially the same in construction and function as the distributing valve device disclosed in the aforementioned pending application 619,052. In view of this a somewhat simplified form of distributing valve device is shown in the drawings. A

The distributing valve device shown in the drawings comprises an equalizing portion I0, an application portion II, a reduction limiting and control valve device I2, a release valve device I3 and a safety valve device i4.

The equalizing portion It comprises a vpiston I5 having at one side a piston chamber 56 which is connected through a passage and pipe I'I to the brake pipe 5, and having at its other side a valve chamber I8 containing a main slide valve I9 and.

' an auxiliary slide valve 20 adapted to be operated by the piston I5 through the medium of a stem 2l with which the piston is provided. It will here be noted that the seat for the main slide valve I9 is Iformed on the upper side of the valve chamberl and the slide valves i5 and 2@ are positioned to suit, but in practice the seat will be located at the bottom of the chamber and the slide valves arranged in the usual manner. The reason for sho-wing the seat and slide valves in this manner is to eliminate, in so far as possible, the tortuosity of the many passages leading to the slide valve seat, thus materially simplifying the showing ofthe invention.

One end of the slide valve chamber I8 is defined by a cap member 22 having screw-threaded connection with the casing of the distributing valve device, said cap member together with .the

casing defining a chamber 23 which is in constant The outer end of the piston chamber I G'isf closed by a cap member 27, a gasket 28, being clamped between the member and casing to prevent leakage ofV fluid under pressure from tleVV chamber to the atmosphere. A portion of this gasket extends into the piston chamber, against which portion the equa-lining piston I5 is adapted to seal when the piston is moved to emergency position.

Slidably mounted in the cap member 2'! is a" piston stop 25 which is urged inwardly toward the equalizing piston I5 by the action of a'c'oil spring 3o, the inward movement of the stop being limited by the engagement of a iiange 3I ,Y

is slidably mounted in a suitable bore'in the casing and which is disposed between the chamber 34and a valve chamber 35 containing a brake cylinder exhaust valve 3! which is adapted to be operated by means of a stem 33 with which the application piston is provided. YThe valve chamber 36 is in constant open communication through a passage andpipe 39 with the brake cylinder 'I and also with the chamber 34 through passageY 39, a branch passage li and the passage in a' choke plug 42 having screw-threaded connection` with the casing.

The application piston 32 besides being adaptedy to shift the brake cylinder' exhaust valvey 37,' isalso adapted to control the operation of a brake cylinder supply valve-device .ber 36. The casing of the device together with the valve piston 45 define chambers 5S and 5I K This supply valve device comprises a casing `which is secured to the y casing of the application portion Ii, and which is which are in constant open communication with eachother through -a passage 52 in the casing. v

Contained in the chamber 5@ is a spring 53r which p is adapted to urge the valve piston into sealing" engagement with the seat rib 48. The chamber Y plication of the brakes.

operable control valve device 9. ""the chamber 61 is a piston 59 having a stem 'I9 5I is vin'constant open communication through-a` passage and pipe 54 .with the'main reservoir I.

The reduction limiting valve device I2 is associated with the equalizing portion and applicationportionof the distributing valve device and in initiating a service application of the brakes.

functions, as will hereinafter more fully-appear, to delay the application of the locomotive brakes for a chosen period of time.

This valve device I2 comprises a casing which in the present embodiment of the invention is Secured to the casing of the equalizing portion of the distributing valve device, and also comprises a-piston 55 having at one side a piston chamber 56 which is connected to a passage 5'! leading to the seat for the equalizing main slide valve I 9. At the other side oi the piston is a valve chamber 58 which is normally connected to a passageA 59 leading to the seat for the slide :valve i9. Contained in the valve chamber 58 is a control slide valve 60 which is adapted to be actuated by the stem 6l of the piston 55. Contained in the piston chamber 55 is a spring 62 which at all times, tendsr to urge the piston toward its normal position, in which position the piston is shown in Fig. 2.

Contained in the valve chamber 58 of the valve device I2 is an expansiblel and rockable strut for exerting seating pressure on the control slide valve 50. This strut comprises a part 63 which is rockably mounted on a pin 54 carried by the casing and alsoV comprises a part 55 which engages the back surface of the slide valve 69 and which is slidably mounted in the part 63 so as to be freely movable in the direction of its length relative to the part 53. Interposed between and engaging said parts is a spring 65 which acts through the medium of the part 55 to urge the slide valve to its seat.

The release valve device I3 is provided for the purpose of controlling the release of the locomotive brakes independently of the operation of the equalizing portion of the distributing valve device, and since the details Yof its construction as well as its function have been fully covered vin the aforementioned. pending application Serial No. 619,052, a detailed description of the same in the present application is deemed unnecessary.

The change-overV control valve devicel 8 is associated with the application portion of the distributing valve device, and as willV hereinafter more fully appear, is selectively operative to one or the other of two positions to control the rateV of increase in the pressure of application piston chamber 33, thereby controlling the operation of the application portion and consequently the locomotive brakes in effecting an emergency ap- This valve device comprises a casing which in the present embodiment ofthe invention is secured to the casing of the distributing valve device. The casing is provided with a .piston chamber 5l which is connected through a passage and pipe 58 to the manually Contained in |`reservoir I by way of a passage 13 and passage and pipe 54. Also contained in the piston chamber 6'! 'is a spring 'I4 which engages the piston and tends to move the piston from the position in which it is shown in Fig. 2.

The manually operable control valve device 9 may comprise a casing, a plug valve 'I5 rotatably mounted in the ,casing and a handle 'I6 for rotating the valve. Withthe plug valve in the position shown inFig. 1, the pipe 68 and consequently the piston chamber 5l of the changeover valve device is connected to the atmosphere through a passage 'I1 in the plug valve and a registering port 18 in the casing. When the handle 'I6 is turned to the position as shown by dotted lines in Fig. 1, the plug valve closes the communication from theA pipe 65 to the atmospheric port 'I8 and the passage 'I'I in the valve establishes communication from the main reservoir pipe 54 to the pipe 68 as will hereinafter more fully appear.

In Fig. l of the drawings the automatic brake valve device 3 and the independent brake valve device 4 shown are each of the usual type, but it will be understood that any other desired type, such as is disclosed in a pending application of Clyde C. Farmer, Serial No. 685,576, may be employed.

The automatic brake valve device shown comprises a casing havingA a rotary valve chamber 'i9 with which the main reservoir I is in constant open communication by way of pipe 54 and a passage 85. Contained in the chamber 'I9 is a rotary valve 8l having an operating stem 82 which is adapted to be rotated by means of a handle 93. The brake valve device also comprises an equalizing discharge valve mechanism comprising a discharge valve 84 and a piston 85 for actuating the discharge valve,

The independent brake valve device comprises a casing having a rotary valve chamber 85 with which the usual reducing valve device (not shown) is connected by way of a pipe 8l. Contained in the chamber 89 is a rotary valve 88 having an operating stem 89 which is adapted to be rotated by a handle 90.

Initial charging In charging the equipment, the independent brake valve device is in running position as shown and as is usual the rotary valve of the automatic brake valve device is turned first to release position and after a predetermined period of time has elapsed is then turned to running position.

With the automatic brake valve device in release position, iiuid at main reservoir pressure flows from the rotary valve chamber i9 Ato the `brake pipe 5 by way of a port 9I in the rotary valve 8I and a passage and pipe 92. Fluid under pressure supplied to the passage 92 flows to a chamber 93 at one side of the piston 85, and from the port 9| fluid under pressure flows through a passage 94 to a chamber 95 at the other side of the piston. From the piston chamber 95 iiuid under pressure ilows through a passage and pipe 95 to the `edualizing reservoir 91.

Now when the rotary valve 8l is turned to running position the port 9| is lapped and the direct flow oi fluid from the main reservoir I to the brake pipe 5 and equalizing discharge valve chambers 93`and 95 is closed oi. Fluid under pressure does however flow from the feed valve device 2 to the brake pipe 5 by way of a pipe and passage 98, a cavity 99 in the rotary valve 8| and passage and pipe 92. From the passage 92 iiuid underpressure Vflows to the chamber 93. From the cavity 99 fluid also iiows through passage 94 to the piston chamber 95. Since the chambers 93 and 95 will be charged with fluid under pressure at. substantially the same rate the force of gravity will maintain the exhaust valve 54 closed.

nected to the passage 3.9, the chamber 34 is also'V Fluid under pressure supplied'to the brake pipe 5 flows therefrom through pipe and passage I1 t@ the equalizing piston chamber I6, and with the equalizing piston I5 in release position as shown in Fig. 2, duid under pressure flows from the piston chamber I6 through a feed grooveV |00 around the piston I5, the opening in a chokeplug IUI and a passage 5.62 to the equalizing valve chamber l5. From the Jchamber kI3 uid under pressure iows past the rear rend of the main slide valve I and through passage 25, chamber 23 and passage 25 to the pressure chamber 25. It will thus be seen that the equalizingvalve chamber I8 and pressure chamber 26 are charged with fluid to the pressure carriedin the brake pipe.

With the equalizing slide valves I9 and 20 in release position and the change-over valve device 8 in position for short train operation, the application piston chamber 33 is open .to the .atmosphere by way of a passage ||i3','a cavity |54 in the change-over slide valve 1i, passages :-|55, |06 and |51, a cavity |58 in the'slide valve 5B of the reduction limiting valve device I2, a passage |09 having a choke plug I Ii!l interposed therein, a pipe and passage Ill, a cavity |I2 in the rotary valve S8 of the independent brake valve device 4, passages and pipe I i3, a cavity IM in the rotary valve 8| of the automatic brake valve device 3 and a passage H5 leading to the atmosphere.

A cavity IE6 in the equalizing main slide valve connects a passage ||1 leading from the application chamber IIB, to the passage |66, and since the latter passage is connected to the atmosphere in the manner justtraced, the application chamber is of course open to the atmosphere.

With the change-over valve device 8 in position for long train operationa cavity illy in the change-over slide valve connects the passage |53 to a passage |29 which is connected to the passage I|1 leading from the application chamber H8 so that the application piston chamber 33vis connected to the atmosphere by way of passage ||1 and the connections therefrom to the atmosphere which have just been traced. The passage|03 is connected through a choked passage I2I to the passage |56 so that the application piston chamber is also open to 'the passage IGS which isgopen to the atmosphere as will be understood.

The reduction chamber |22 is connected to theatniosphere by way of a passage |23, a branch passage |24, a cavity |25 in the equalizin'g main slide valve I9 and a passage |28 leading to the atmosphere.

The piston chamber 56 oi the reduction limiting valve device 2 is connected to the atmosphere by way of passage 51, a port I21.,in the equalizing main slide valve I9, cavity ||6 to which the port is connected, passage |116 and through the connections from -the passage |56 as hereinbefore traced. The valve chamber 58 is connected to the cavity H6 throughpassage 59 and a port '|28 in the main slide valve IS and is therefore connected to the atmosphere by way of passage H35. Withthe'chambe'rs' and 578 thus connected to the atmosphere the spring 62 yieldably maintains the piston 55 and associated slide valve 55 in release position as shown in Fig. v2.

With the applicationk piston 3 2 and theA yassociated brake cylinder releaseV valve 31 in release position as shown in Fig. V2, the brakecyl- Since the passage 4| is conconnected to theA atmosphere.

Fluid under pressure ilows fromthe main reservoirby'wayof pipe and passage 54 to the application valve chambers and 5|. VWith the application piston in release position, thespringY l35fand uid under jpressure in chamber 55 act to maintain the'application valveseated so that the chambers 5B and 5| kare 'charged with uid at main reservoir pressure.

vFrom thepassage 54 iluid at main reservoir pressure flows thro-ugh passage 13 to the valve chamber 12 of the change-over valve device 8 and holds the change-over piston and thereby the change-'over slide valve 1I in the position shown in Fig. 2 against the opposing pressure of thespring 14 only, the piston chamber 61 being open to the atmosphereby Way of passage and pipe 68, passage 11 in `the valve device 9 and port `18. i

' 'Service application When it spdesiredito elect a service `application of the brakes on a train, the rotary valve 8| of the automatic brake valve device 3 is turned to service position in which a choked passage |35 leading from the equali'zing dischargevalve piston chamber 95 vis connected by a .cav-

mospheric `passage II5, so that the piston chamber is reduced at a rservice rate `as governed bythe choke in the passage 30. Fluid at brake pipe pressure in chamber y93 acting on the other side of the equalizing dischargeV valve piston 85 causes the piston to function in the usual manner to control the movement of the discharge valve 84 to vent fluid under pressure from the brake pipe and consequently from the equalizingpiston chamber I of the distrib-v uting valve device at substantiallythe same rate as fluid is being vented from the piston chamber 95.

Upon a light gradual reduction in the pressure offluid inthe equalizing piston chamber I5, resulting from the venting of fluid from the chamber, the pressure'ofv fluid 'inthe equalizing valve chamber I8 causesrthe equalizing piston I5 to move outwardly to service position, in which positionthe'` piston isbrought to a stop by the action of the spring-stop 29. i

The equalizing piston- I5, in its traverse to service position, first closes communication between the piston chamber I6 and valve chamber I8 by way of the feed-groove |430 and shifts the t moveszthe auxiliary andmain'slide valves k2|) and I9, respectively, in unison toward service position. Upon the initial "movement of the main slide'valve the cavity |25 therein ismoved out of registration with the atmospheric passage |25 and as a result the atmospheric communication from the reduction chamber V|22 is disestablished, and ythen astheslide valve moves into'service position, a cavity |33 in the main slide valve establishes communicationfrom the passage 51 and thereby the reduction limiting valve piston chamber 55 to the passage |26 leading `.to the atmosphere so that the chamber 56 will be maintained: at atmospheric pressure.V At substantially the same time as the communication fromthe' passage 51 kto the passage |26 is established,` 'raport |34 in the mainy slide valve a cavity |40 in the control slide valve 60 of the reduction limiting valve device I2 and passage I23'to the reduction chamber |22, and since the service port |32 is open to the equalizing Valve chamber I8 fluid under pressure now flows from this valve chamber and pressure chamber 26 to the reduction chamber. i

' With the main slide valve I9 in service position the passage |24 leading from the passage |23 connected to the reduction chamber |22 is connected by the cavity |25 in the main slide valve to the passage 59 which leads to the valve chamber 58 so that fluid under pressure supplied from the equalizing piston chamber and pressure chamber |28 to the reduction chamber |22, by way of passage I 23, liowsrto the valve chamber 58. f Y

Now when the fluid pressure in the reduction chamber has been increased to around iifty pounds, fluid at this pressure in the valve chamber 58, acting'on a small areaof the back of the piston within a seat rib |42 against which the piston is held seated by the action of the spring 62, causes the piston to move out of seating engagement with the seat rib. Just as soon as the seal between the piston and the seat rib is broken, fluid under pressure in the chamber 58 acts over the entire area of the back of the piston and causes the piston and thereby the control slide valve to move with a snap action to their extreme outer position,the piston compressing the spring 62 and sealing against a gasket |43 as shown in Fig. 4.

The slide valve 60 in its traverse to the position in which it is shown in Fig. 4 laps the passage 59, thus disestablishing the communication from the reduction chamber to the valve chamber 58 and at substantially the same time laps the release passage |09, thus disestablishing the communication from; the application piston chamber 33 and application chamber 26 to this release passage. At substantially the same time as these passages are lapped the slide valve uncovers one end of a passage |44. The other end of the passage being previously uncovered by the main slide valve I9, uid under pressure flows from the equalizing valve chamber I8 to the Valve chamber 58 of the reduction limiting valve device. Further, the slide valve 60 in its traverse iirst disestablishes the communication betweenV the passages |39 and |23 so that the flow of fluid from the equalizing valve chamber I8 and pressure chamber to the reduction chamber is closed off, and then brings the cavity I 08 into communication With the passage |39. Since the passage |01 is already in communication with the cavity |38, fluid under pressure now ows from the equalizing valve chamber I8 and connected pressure chamber I I8 to the application piston chamber 33 by Way of the service port |32 in the main equalizing slide valve I9, toe cavity |38, passage |39, cavity I 08 in the vcontrol slide valve 60 of the reduction limiting valve device I2, passages |01, |08 and |05, cavity |04 in the slide valve 1I of the change-over valve device 8 and'passage |03. Fluid under pressure may also iiow through the choked passage I 2| from the passage I 0S to the passage |03.

Fluid under pressure thus supplied to the passage |05 also flows to the application chamber |I8 by way of cavity II6 in the main equalizing slide valve I9 and passage I I1.

From the cavity |I6 fluid under pressure also flows to the safety valve device I4 by way of port |31 in the equalizing main slide valve I9, cavity |38 in the equalizing auxiliary slide valve 20, port |34 in the main slide valve and passage |35.

Fluid under pressure supplied to the application piston chamber 33 causes the application piston 32 to move inwardly, that is to say, in a rdirection toward the right hand, said piston,

through the medium of the piston stem 38, shifting the brake cylinder exhaust valve 31 to close the communicationirom the valve chamber'38 and connected brake cylinder 1 to the atmospheric exhaust passage |28.

' As the piston continues to move in this direction, the end of the piston stem 38 engages and moves the valve piston 48 and thereby the gasket 41 out of seating engagement with the seat rib 48 against the resistance offered to such movement by the spring 45 and the pressure of iluid in chamber 58. Fluid at main reservoir pressure now flows to the brake cylinder by way of pipe and passage 54, chamber 50, past the unseated valve piston and through passage and pipe 39.

From the passage 39, fluid under pressure also flows through passage 4| and the passage in the choke plug 42 to the chamber 34 at the back of the application piston 32.

When, with the valve piston 46 thus unseated, the rate of increase in brake cylinder pressure substantially equals the rate of increase in the pressure of fluid in the application piston charnber 33, the application piston 32 will come to a stop, and the flow of iluid to the brake cylinder at a rate corresponding to the rate of increase in the application piston chamber pressure continues.

From the foregoing description it will be seen that the equalizing portion of the distributing valve device promptly moves to service application position following the initiation of a gradual reduction in brake pipe pressure, and that an application of the brakes is held back until a chosen fluid pressure, of for instance fty pounds, is obtained in the reduction reservoir |22.

It is well known that when a car brake cylinder piston is moved outwardly toward brake applying position by iluid supplied through the medium of a triple valve device, a certain amount of Huid is required from the auxiliary reservoir to ll the vacuum space created by the movement of the brake cylinder piston before an eflfective braking force is applied to the car, while on the locomotive, since the application chamber II8 is initially at atmospheric pressure, fluid under pressure supplied to this chamber from the pressure chamber 28, in the absence of the reduction chamber |22 and reduction limiting valve device I2, would become immediately effective to operate the application portion of the distributing valve device to supply iluid under pressure to the locomotive brake cylinder, and for the same degree of reduction in the pressure of the pressure chamber as occurs in the auxiliary reservoir on the car, a higher pressure would be obtained in the application chamber of the distributing valve device and consequently in the vlocomotive brake cylinder than is obtained in the car brake cylinder. This would,

fof course, result in a more rapid retardation of the locomotive than of the cars,and such braking action t-endsto cause the slack in the ytrain .to run in or rclose toward the locomotive in a harsh and therefore dangerous manner.

,In the present embodiment of the invention the volume of the reduction reservoir |22 is so .plication piston chamber proportioned to the combined volumes of the pres- `sure chamber 26 and equalizing valve chamber I8 that when a pressure of approximately fifty Vpounds is obtained in the reduction chamber,

a reduction of approximately five pounds is efected in the pressure oi the pressure .chamber A28, regardless of the pressure to which thepres- Ysurechamber is initially charged Afrom the brake pipe. From this it will be evident that regardless of the brake pipe pressure normally carried v,the reduction limiting Valve device I2 functions to limit the reduction in the pressure of the pressure chamber to around iive pounds, which corresponds to the reduction required in the auxof reduction in auxiliary reservoir pressure re- `o luired to initiate an effective braking action on a car, the locomotive brakeswill be applied in substantial synchronization with the car brakes,

and as a result the harsh slack run in or run Vout shocks, hereinbefore referred to are prevented.

n When in effecting a limited application or" the brakes, the pressure of fluid vin the equalizing valve chamber i3 is reduced, by the iiow of fluid therefrom to the vapplication piston chamber 33 and application chamber l i8, to a pressure slightly'below the brake pipe pressure in the equalizing piston chamber I5, the equalizing piston will be caused to move inivardly,rthat Vis to say in a direction toward the left hand, shifting the equalizing vauxiliary slide valve 2!l relative to the main slide valve I9 to iirst lap the port I 34 which is in communication with the passage |35 leading to the safety valve device I4, and then lapping the service port |32 to -close off any further now of uid from the equalizing valve chamber I8 and pressure chamber`26 to the ap- 33 and application chamber I I8. With the service portlapped, the

pressures on opposite sides of 'the equalizing pis- 4thus closed oil, the pressures on opposite sides of the application piston are substantially equal, the valve piston 45 will, under the influence of the action of the spring 45 and the pressure of fluid in chamber 59, be moved into seating engagement with the seat rib 4S, the valve piston asin `is, thus moved, shifting the applicationV piston forwardly to its lap position in which the Y brake cylinder exhaust valve 97 still maintains the communication closed from the brake cylinder to the atmospheric passage |29.

Release of bra-kes after d servicel application When it is desired to release the brakes after l. a service application of the brakes has been ef- Mfected, the rotary valve 8 |l ofthe automatic brake determined period of time has elapsed, is turned to running position to effect the usual increase in brake pipe pressure. pressure is also effective in the equalizing piston chamber I5, the equalizing piston I5 and thereby the slide valves I9 and 29 are caused to move to release position, in which fluid under pressure in the valve chamber 5S of the reduction limiting valve device equalizes into the pis- Yton chamber 56 of the device by Way of passage M4, a port |45 in the main slide valve I9, cavity H6,V port |21 and passage 5l. i

' With the fluid pressures on opposite ksides of the piston 55 thus equalized, the spring 62 acts to shift the piston and thereby the control slide valve 50 to release position in Which the cavity |08 again establishes communication between the passages IQ'I and I 89 and in Which the cavity |40 again establishes communication between the .passages I23 and |39.

When the passages |07 and |39 are thus connected, `iiuid under pressure is vented from the application piston chamber 33 to the atmosphere *by Way of passage |03, cavity HB4 in the changeover slide valve TI, passages |95, |05 and |01, cavity |08 in the slide valve 60, passage |09, pipe and passage III, cavity 2 in the rotary valve 88 ofthe independent brake valve device, with this brake valve device in running position, passages and pipe ,II3, cavity H4 in the rotary l Valve 8| of the automatic brake valve device and passage I I5. Since the passage l Il leading from the application chamber l I8 is connected by way rof cavity H6 in the main slide valve I9 to the passage S95, fluid under pressure is also vented from the application chamber to the atmosphere. With the slide valve 550i the reduction limiting valve device I2 in release position the Valve chamber 58 is connected through passage 59 and port |28 to the cavity i5 in the-main slid-e valve and uid under pressure from said chamber is consequentlyvented to the atmosphere. The passage 5l leading from the piston chamber 56 of the .valve device |2 is connected by Way of port |21 to the cavity |6,.so that fluid under pressure is also vented from this chamber to the atmosphere. Fluid under pressure is vented from the reduction chamber |22 by Way of passages |23 and |24, cavity |25 in the main slide valve I9 and passage |26.

With the application piston chamber vented to the atmosphere, fluid at brake cylinder .pressure in chambers 34 andv35 of the applicationv f portion causes the application piston 32 and thereby the brake cylinder exhaust valve 3T to move to release position, as shown in Fig. 2, in which position iiuid under pressure is vented 4from the brake cylinder to the atmosphere by Way of pipe and passage 39, brake cylinder exhaust valve chamber 95 and passage 95.

Theseveral parts or the equipment beingr now in release position, the charging of the equipment vwill be the same as described in connection with the initial charging.

Emergency application of the brakes I In handling a short train such as is employed in passenger service and Where the run-in of' slack in the train is not sumcient to cause harsh .damaging shocks, the plug valve is'not moved v from the position in which it is shown in Fig. 1

in eecting either va service or an emergency lapplication of the` `brakes, and due tov this, the

Since this increase in?` emergency change-over valve device 81 will remain in the position inv which it is shown inf Fig.:2.

`However, in handling a long train'of from one hundred to one hundred fifty or more cars-Where thel slackin the train is suiicient to cause harsh ydangerous shocks, the plug valve l5 of the valve device 9 is rotated 90 from the position in-which it is shown in Fig. 1, preparatory to initiating an emergency reduction in brake pipe pressure. With the plug valve in this'position, the cornmunication from the pipe 63 and consequently from lthe piston chamber |51 of the change-over valve device 8 to the atmosphere by way of passage 'I'I and port 'I8 is disestablishedanda communication is established by the passage 'I'I from the main reservoir pipe 54 to thepipe 68, through which communication fluid under pressure from the main reservoir I flows to the change-over piston chamberV 6l.

Since the valve chamber 'I2 of the emergency change-over valve device 8-is charged with uid at main reservoir pressure by way of passage 13,

the fluid pressures on opposite sides of the changeposition. the communication between the passage |03 and the passage |05 which by-passes the choked passage I 2| is disestablished and the passage |83 is connected by cavityv IIQ in the slide valve to the passage |20 leading tothe passage I which is connected to the application chamber Now when the rotary valve 8| of the automatic bra-ke valve device is turned to emergency` position, fluid under pressure is rapidly vented from the brake pipe to the atmosphere by'wayof pipe and passage 92, a cavity |41 in the rotary valve f 8| and passage I 5. The rapid reduction in brake pipe pressure causes a corresponding rapid reduction in the pressure of fluid in the equalizing emergency position overcoming the resistance offered by the spring-pressed stop 29 and engaging the gasket 28 as shown in Fig. 5.

In the emergency position of the mainequalizing slide valve i9 fluid under pressure is permitted toflow from the equalizing valve chamber '.I8 .and

consequently from the pressure chamberi26 to vthevalve chamber 58 of the reduction .limiting valve device I2 by Way of passage 24, a port |41 in the main slid-e valve, cavity |25 and passagei59. Thevolume of the valve chamber is small, consequently a pressure in this chamber sufficient Yto move the piston and thereby the control slide valve 60 to application position against theoppo- 'sition offered by the spring 62 is quickly. built up so that thereis no material delayin themovement of the piston and slide valve to application position as there is in effecting a service application.

With the equalizing portion of the distributing `valve device in emergency position and the reduc- .tionlimting valve device in applicationposition, fluid under pressure flows from equalizing valve chamber I8 and pressure chamber '26 through an emergency portr=|48and theservice Vport |32 Vrinthe'main slide valve IQ to the cavity |38, and from thence flows through passage |09, cavity |08 in the slide valve 6G of the reduction limiting valve device I2, passages |01 andv |06, choked passage I2 I- and passage |83. Fluid under pressure from lthe passage |83 also flows toilthe .application chamber II8 by way of cavityf I'I9 and passages |23'and I II'. From an inspection of Fig. 5 it will be seen that in emergencyiposition the main slide valvelaps one end of the passage II'Ileading tothe application chamber |I8, .thus preventing lthe'flow of iiuid from the passage |06 to thepassage III byV way of cavity IiS `inlthe main slide Valve. It will thus be seen that the flow Lof fluid under pressure to both the application piston chamber 33 and application chamberY I8 can occur only by way-of the restricted passagev II2I and that rthe rate of increase in these chambers is governedaccording to the ilow 4area of said passage. f

"Due to the restricted flow of iiuid to the applicationpiston chamber 33 and application chamber ||8,1 the increase in the pressure of iluid in the application piston chamber 33 will be at a` slower rate than would be the case if the restriction in the passage |2| and the connection from the application piston chamber to the application chamber were omitted.

-Fluid under pressure supplied to the applica- Ytion piston chamber 33 causes the application piston32Y and thereby the brake cylinder exhaust kvalve 3'I to move in the same manner as ineffeeting a service application of the brakes, the 'piston-stem 38 engaging and moving the valve piston 46 away from the seat rib 48, permitting yiluid at main reservoir pressure to flow to the -brake cylinder Withuid under pressure being supplied to the brake cylinder, the application piston functions in thesame manner as in effecting a service application of the brakes to control the operation of the valve piston 45 to regulate the rate of inlcrease in brake cylinder pressure according to the vrate of increase in the pressure of fluid in the application piston chamber 33, and since the rate of increase in the pressure of fluid in the application piston chamber is retarded, the rate of increase'in'brake cylinder pressure` is correspondingly retarded.`

` Due to this, the braking power of the locomotive'brakes, in eiecting an emergency application of the brakes, will be increased in such a gradual manner as to materially contribute to the gentle gathering or closing of slack in the train.

It willhere be noted that in effecting an emergency v application of the brakes, the reduction limiting valvedevice will move so rapidly under the influence ofl pressure chamber pressure that there will be no appreciable flow of iluid from the equalizing valve chamber `I8 and pressure chamber 26 to the reduction chamber by Way of passage I SSL-cavity |40 in the slide valve 60 and passage l |23, lbut it is not necessary that the reduction reservoir function to reduce the pressure chamber l pressure in effecting an emergency application.

With the rotary valve 8| of the automatic brake valve device in emergency position, the feed valve passage`98 is connected through a cavity |50 in the rotary valve and a passage and pipe' |5| to the application and release pipe I I I, so that-iluld at the pressure supplied bythe feed valveidevice 2 is supplied to the equalizing valve chamber I8 rand pressure chamber 26 by way of passage |09, a chamber .|52 in the independent brake valvede- Jvice I3, past the cut-ofi` valve |53-of the device' I3,

a chamber |54, a passage |55 and passage |01 in connection with the release of the brakes folwhich, at this time, is connected to the equalizing valve chamber and pressure chamber. Fluid under pressure thus supplied from the feed valve device 2 maintains the pressure in the .equalizing valve chamber I8 and pressure chamber 26 against leakage of fluid from these chambers.

On a short train such as is employed in passenger service where the slack in the trainis not great enough to cause harsh damaging shocks, the plug valve 15 is not turned from the position in which it is shown in Fig. 1 preparatory to effecting an emergency application, so that the emergency change-over'valve device will remain in the position in which it is shown in Fig. l.

With the emergency change-over valve device in this position, the passage I I9 connected to the application chamber II8 by Way of passage I I1 is blanked by the change-over slide valve 1| and the passage |03 leading to the application piston chamber 33 is connected by the cavity |20 in the slide valve to the passage |05. Y

When the several parts of the equalizing portion of the distributing valve device are shifted to emergency position, fluid under pressure is supplied through passages I06 and |05, cavity |20 in the change-over slide valve and passage |03. The main equalizing slide valve I9 in emergency positions laps the passage ||1, so that fluid under pressure cannot flow from the passage |06 and cavity VI I6 to this passage and since the passage |20 is blanked there will be no flow of fluid from the equalizing valve chamber I8 and pressure chamber 26 to the application chamber I I8, so that the increase in the pressure of iiuid in the application piston chamber 33 and consequently in the brake cylinder 1 will be at a faster rate than when the application chamber is in communication with the application piston chamber.

Safety valve device The safety valve device I4 is adapted to function in effecting either a service or an emergency application of the brakes to vent fluid under pressure from the equalizing piston chamber I8 and pressure chamber 26 when the pressure in these chambers exceeds the setting of the device to prevent an excessive brake cylinder pressure on the locomotive. Since this feature has been fully described in the aforementioned pending application, Serial No. 619,052, it is deemed unnecessary to repeat the description here.

Release ofthe brakes after an emergency application If the plug valve 15 of the valve device 9 is in the position for long train operation', the engineer may, if heso desires, turn the valve to the positienin which it is shown in Fig. 1, so as to vent fluid vunder pressure from the piston chamber 61 of the change-over valve device 8 to the atmosphere. With the chamber 61 thus vented, fluid at main reservoir pressure in chamber 12 causes the change-over piston 69 and thereby the slide valve to move outwardly,4 against the opposing pressure of the spring 14, to the position in which they are shown in Fig. 2.

Now when it is desired to release the brakes, the rotary valve of the automatic brake valve device 3 is turned to release position and then to running position in the usual manner to increase the brake pipe pressure. The increase in brake pipe pressure causes the several parts of the equipment to move to release position in substantially the same manner as hereinbefore described lowing a service application.

In long Ytrain operation, if the engineer fails to move the plug valve 15 to the position in which it is shown in Fig. 1, the release of fluid under pressure from the application piston chamber 33 will be by way of the restricted passage |2I, but since the chamber 33 is of small volume the retardation in the reduction of application piston chamber pressure and consequent retardation of the reduction in locomotive brake cylinder pressure will be negligible, as will no doubt be readily understood. Y Y

The broad ideaof controlling the rate of increase in the locomotive brake cylinder pressure in effecting an emergency application of ,l the brakesand the idea of rendering such'control either effective or ineffective is not claimed in the present application, since these featuresare the invention of Charles H. McKinstry, Vand are coveredv in his hereinbefore mentioned 'application, Serial No. 690,685,1iled September 23, 1933.

While one illustrative embodiment of the in-y vention has been described in detail, it is not my intention to limit its scope to that embodiment or otherwise than by the terms of theY appended claims.

Having noW described my invention, What-I claim as new and desire to secure by Letters Patent, is: Y f

1. In a fluid pressure brake, the combination With a brake pipe and a, chamber charged with fluid under pressure, of valve mechanism subjectto the opposing pressures of the brake pipe and chamber and operated upon a reduction in brake pipe pressure for initiating a reduction in the pressure of fluid in the chamber, and means separate from said valve mechanism Yoperable upon the operation of the valve mechanism-for first limiting the reduction in the pressure of fluid in said chamber and for then supplying fluid under pressure from said chamber to cause an application of the brakes to be initiated.

2. In a fluid pressure brake, the combination with a, brake pipe and a chamber charged with fluid under pressure, of valve mechanism subject to the opposing pressures of the brake pipe and chamber andV operated upon a reduction in brake pipe pressure for initiating a reduction'in the pressure of fluid in the chamber, and means separate from said valve mechanism operative only after the pressureof fiuid in said chamber' has beenreduced a chosen amountfor supplying :duid under pressure to cause an application of the brakes tovbe initiated, saidmeans being cut in operation upon the operation of the valve means. 4

3. In a fluid pressure brake, the combination With a brake pipe and a chamber charged with fluid under pressure, ofvalve mechanism subject to the opposing pressures of the brake pipe and chamber and operated upon a reduction in brake pipe pressure for effecting a reductionA in the pressure of fluid in the chamber, valve means separate from said valve mechanism operative to supply fluid under pressure from said chamber to cause an application of the brakes to bein-` itiated, and means for delaying the operation ofi sure from' vsaid chamber" to effect a reduction-in the pressure of fluidin the chamber, and' means responsive to' the pressure of fluid ventedl from saidchamber for rst limiting the amountl of fluid vented from said ychamber and for then supplying fluidY under pressure to cause an appli'catlon of thebrakes to'be initiated.

r5. In a fluid pressure brake, the combination with a brake pipe and a chamber charged with fluid" under pressure, of valve mechanism subject tothe opposing pressures of the brake pipe andv chamber and operated upon a reduction in brake pipe pressure for venting fluid under pressure-from said chamber to effect a reduction in thepressure of iluid in the chamber, a reduction reservoir, a valve normally establishing a communication through which fluidl vented from said chamber by said valve-mechanism flows tosaid reduction reservoir and operative to close said communication and toA establish another communication through which fluid under y pressure -from said chamber is' adapted to flow' to cause an' application of the brakes to be effected, a movable abutment responsive to the pressure of fluid vented from said chamber to said reservoir' in effecting the reduction inthe chamber pressure for actuating said valve, and means for delaying the -movelnent of said abutment until g the pressure of fluid acting thereon has been increased a chosen degree.

l6. In a fluid pressure brake, the combination with a brake pipe, a chamber charged with fluid under pressure and a reduction reservoir, of valve ,p mechanism subject to the opposing pressures of the brake pipe and chamber and operated upon a reduction in brake pipe pressure for venting fluid under pressure from said chamber-to said reservoir, and means responsive to a chosen pressure in said reservoir for limiting the amount of fluid -vented from said chamber and for establishing a communication through Which fluid from said chamber flows to cause an application of the brakes to be effected.

7. In a fluid pressure brake, the combination with a brake pipe, a chamber charged With fluid under pressurek and a reduction reservoir, of*` valve mechanism subject toithe opposing pressures of the brake piperand chamber and operated upon a reductionin brake pipe pressure "for establishing a communication through' which' iluid under'pressure is vented from said chamber, and valve means.normally-establishing a communication through which fluidunder pressure is vented from said 'chamber' to said reservoirY and operative by fluidunder pressure vented to said reservoir for disestablishing'said communication to limit the reduction in the pressure of fluid'in said chamber and forvestablishing another communicationr through which fluid vented' from said chamber'by Way of the valvel mechanism flows to cause an application 'of the brakes to be effected. f

8. Ina fluid pressure brake,`the combination with a brake pipe, a chamber charged with fluid under pressure and a reduction reservoir, of valve mechanism subject to the opposing pressures of the brake pipe and chamber and normally establlshing acommunicationfromsaid reservoir to the atmosphere, said valvemechanism being operated upon a reduction in brake pipe pressure for'rst closing said communication and for then establishing another communicationA V'through which uid under pressure is-vented from said chamber, 'a valve normally establishing a communication through vvhichl fluid vented fromsaid chamber-flows to said" reservoir, and meansre'- sponsive to Aa chosen reservoir, pressure for'Vac-i tuatingsaid valve to disestablish the last mentioned communication and to establish another communication through which lluidvented from said chamber by 'said valve mechanism flows to cause an application of the brakes to be effected.

9. In a fluid pressure brake, the combination with a brake pipe, a chamber charged with fluid underV pressure and a reduction reservoir, of valve mechanism subject toV the opposing pressures of the brake pipeand chamber and 'normally establishinga communication from said reservoir tothe atmosphere, said valve mechanism being operated upon a reduction in brake pipe pressure for first closing said communication and for then establishing another communication through which fluid -under pressure is vented fromY said chamber, a valvenormally establishing a communication through which fluid vented from said chamber flows to said reservoir and being movable to a position for disestablishing the last mentioned communication and for establishing another communication through which fluid under pressure vvented from l said chamberv by way of said valve mechanismilows toV cause an application 'of the vbrakes to be ef'- fected, and means operative by-nuid under pressure from saidy reservoir for moving said valve, the operation of said means being delayed until a chosen'iluid pressure has been obtained in said reservoir. 1

10. In a; fluid pressure brake, the combination with a brakepipe, a chamber charged with fluid under' pressureand a reduction reservoir, of valve mechanism subject to the opposing pressures of the brake pipe and chamber and normally establishing a communication from said reservoir tothe atmosphere, said valve mechanism being operated upon a reduction in brake pipe pressure for rst closing said communication and for then establishing another communication ythrough which iluid under pressure is vented from said chamber, a valve normally establishing a communication through which fluid vented from said chamber flows to said reservoir and beingmovable to a position for disestablishing the last mentioned communication and for establishing another communication through which fluid under pressure vented from said chamber by Way of said valve mechanism flows to cause an application of the brakes to be effected, means operative by iluid under pressure from said reservoir for moving said valve,and yieldable resistance means for delaying the operation of said means until the presslu'e of fluid in saidreservoiris increased to a chosen value.

11. In a fluid pressure brake, the combination with a brake pipe, achamber chargedwith fluid` under pressure and a reduction reservoir; of valve mechanism subject tothe opposing pressures of the brake pipe and chamber and normally-establishing a communication from said reservoir to the atmosphere, said valve mecha'- nism being operated upon a reduction in brake pipe pressure for rst closing said communication and for then establishing another communicationY through which iluid under pressure is vented from said chamber, a valve normally establishing a communication through which fluid vented from said chamber flows to said reservoir and being movable to a position-for disestablishing the last mentioned communication and for `establishing another communication through Which iluid under pressurevcnted from said chamber by Way of said valve mechanism ilows'to cause an application of the brakesv to be effected, means operative by iluid under pressure from said reservoir for moving said valve, and a spring for delaying the operation of said means until the l pressure of fluid in said reservoir is increased to a chosen value.

12. In a fluid pressure brake, the combination with a brake pipe and a chamber charged with fluid under pressure, of valve mechanism subject to the opposing pressures of the brake pipe and chamber and operated upon a reduction in brake pipe pressure for venting fluid Linder pressure from said chamber to effect a reduction in the pressure offluid in the chamber, and means responsive to the pressure of fluid vented from said chamber and regardless of the pressure to which the chamber is normally charged for first limiting the amount of fluid vented from the chamber and for then supplying fluid under pressure from the chamber to cause an application of the brakes to be effected. h

13. In a fluid pressure brake, the combination with a brake pipe and a chamber charged With fluid under pressure, of valve mechanism subject to the opposing pressiues of the brake pipe and chamber and operated upon a reduction in brake pipe pressure for venting fluid under pressure from said chamber to effect a reduction in the pressure of fluid in the chamber, and means responsive to the pressure of fluid vented from said chamber for first limiting the amount of fluid vented from said chamber regardless of the pressure to which the chamber is normally charged and for then supplying fluid under pressure to'cause an application of the brakes to be effecmd.

14. In a fluid pressure brake, the combination with a brake pipe, a chamber charged with fluid under pressure and a reduction reservoir, of valve mechanism subject to the opposing pressures of the brake pipe and chamber and operated upon a reduction in brake pipe pressure for Venting fluid under pressure from said chamber to said reservoir, and means responsive to a chosen pressure in said reservoir and regardless of the pressure to which the chamber is normally charged for limiting the amount of fluid vented from said chamber and for establishing a communication through which fluid from said chamber flows to cause an application of the brakes to be effected.

15. In a fluid pressure brake, the combination with a brake pipe, a chamber charged With uid under pressure and a reduction reservoir, of valve mechanism subject to the opposing pressures of the brake pipe and chamber and normally establishing a communication from said reservoir to the atmosphere, sai-d valve mechanism being operated upon a reduction in brake pipe pres-- sure for rst closing said communication and for then establishing another communication through which Afluid under pressure is vented frompsaid chamber, a valve normally establishing a communication through which fluid vented from said chamber flows to said reservoir and being movable to a position for Vdisestablishing the last mentioned communication and for establishing another communication through which fluid under pressure vented from said chamber by Way of said valve mechanism flows to cause an application of the brakes to be effected, an-drmeans operative only when the pressure of fluid in said reservoir is increased to a chosen value for moving said valve, said means being responsive to the establishing a communication through which fluid under pressure is vented from said chamber, a valve having means normally connecting the second mentioned communication to said reservoir to permit iluid vented from said chamber to flow to said reservoir, said valve being vmovable Vto a position for disconnecting the second mentioned communication Y from said reservoir and for establishing a connection through Which fluid vented from said chamber by way of the second mentioned communication flows to cause an application of the brakes to be effected, and means operative by fluid under pressure from said reduction reservoir When the reduction reservoir pressure has been increased to a chosen value for moving said valve. y Y

17. In a lluidpressure brake, the combination .with a brake pipe, a chamber charged with fluid under pressure and a reduction reservoir normally communlcating With the atmosphere, of a valve mechanism subject to the opposing pres-` sures of the brake pipe and chamber and operative` upon a reduction in brake pipe pressure for` nrst disestablishing the communication from said reservoir to the atmosphere and for then establishing a communication through' which lluid under pressure is vented from said chamber, a valve having means normally connecting the second mentioned communication to said reservoir to permit fluid vented from said chamber to flow to said reservoir, said valve being movable to a position for disconnecting the second mentioned communication from said reservoir and for establishing a connection through' which fluid Vented from said chamber by Way of the second mentioned communication flows to cause an application of the brakes to be effected, means responsive to a chosen reduction reservoir pressure Vfor moving said valve, and means for delaying the operation of said means until the chosen reduction reservoir pressure has been obtained.

18. In a iluid pressure brake, the combination with a brake pipe, a chamber charged With fluid under pressure anda reduction reservoir, of a Valve mechanism subject to the opposing pres# sures of the brake pipe and chamber and operative upon a--reduction in brake pipe pressure to a service application position for venting fluid under pressure from said chamber, means normally Yestablishing a communication through which fluid vented from said chamber flows to said reservoir and operative upon an increase in the reduction reservoir pressure to a chosen degree to disestablish said communication and to establishav communication through Which fluidv vented from the chamber flows to cause an application of the brakes to be effected.

1 9. In a fluid pressure brake, the combination with a brake pipe, a chamber charged with uid under pressure and a reduction reservoir, of a valve mechanism subject to the opposing pres-1 sures of the brake pipe and chamber and opera` tive upon a reductionin brakeV pipe pressureto a service application position for venting fluid under pressure from said chamber to said reservoir, and. means responsive to a chosen reduction reservoir. pressure for closing oif the flow of uid to said reduction .reservoir and for establishing a communication through which fluid from said chamber flows to cause an application of the brakes to be effected.

20. In a fluid pressure brake. the combination Witha brake pipe, a pressure chamber and a reduction reservoir, of a valve'device subject to the opposing pressures of the brake pipe and the pressure chamber and movable upon a reduction in brake pipe pressure to a posit-ion in which communicationis established from the pressure chamber to the reduction reservoir, and a valve deviceoperated upon a predetermined increase in the kpressure of fluid vented to the reduction reservoir for cutting olf said communication and for opening 'a communication through which uid under pressure is supplied from the pressure chamber to effect an application of the brakes.

. 21.v In a fluid pressure brake, the combination with afbrake pipe, a pressure chamber and a reduction reservoir, of a valve device subject to the opposing pressures of the brake pipe and the pressure chamber and movable upon a reduction in brake pipe pressure to service application position in vwhich communication is established from the pressure chamber to the reduction reservoir, a. valve operable for cutting off said communication and for opening a communication through which iluid under pressure is supplied from the pressure chamber to eiect an application of the brakes, and means operated upon a predetermined increase in the pressure of fluid in the reduction reservoir for actuating said valve. f

- 22. In a uid pressure brake, the combination with a brake pipe, a pressure chamber and a reduction reservoir, of a valve device subject to the opposing pressures of the brake pipe and the pressure chamber and movable upon a reduction in brake pipe pressure to service application position in which communication is established from the pressure chamber to the reduction reservoir, and a valve device oper-ated upon a predetermined increase' in the pressure of fluid vented to the reduction reservoir for cutting off said communication and for opening a communication through Which fluid under pressure is supplied from the pressure chamber to effect an application of thebrakes, the vfirst mentioned valve device being movable when the pressure chamber pressure is reduced slightly below that of the reduced brake' pipe pressure frornrservice application position to a'position for closing off the flow of fluid through the lastimentioned communication.

23. In a duid pressure brake. the combination with a brake pipe, a pressure chamber and a reduction reservoir. of a valve device subject to the i opposing pressures of the brake pipe and the pressure chamber and movable upon a reduction in brake pipe pressure to service application position in which communication is established from the pressure chamber to the reduction reservoir, and a valve device operated upon a predetermined inpressurechamber to" effect an application of the brakes, the rst mentioned valve device after having been moved to service application position being movable upon variations in brake pipe pressure and pressure chamber pressure for controlling the flow of fluid through the last mentioned communication.

24. In a fluid pressure brake, thecombination With a brake pipe, a chamber charged with fluid under pressure and a reduction reservoir, of a valve mechanism subject to the opposing pressures of the brake pipe and chamber and operative upon a reduction in brake pipe pressure to a service application position for venting fluid under pressure from said chamber to said reservoir, and means responsive to a chosen reduction reservoir pressure for closing off the flow of fluid to said reduction reservoir and for establishing a communication through which fluid from said chamber flows to cause an application of the brakes to be effected and to disestablish a communication through which said means is subject to the reduction reservoir pressure and to establish a communication thro-ugh which said means is subjected to the pressure of said chamber.

25. In a fluid pressure brake, the combination With a brake pipe and a chamber charged with fluid under pressure, of a reduction chamber, a distributing valve device comprising an equalizing portion subject to the opposing pressures of the brake pipe and chamber and operated upon a reduction in brake pipe pressure to serve application position for venting luid under pressure from said chamber to said reservoir and operative upon an increase in brake pipe pressure to a brake releasing position, and also comprising an application portion adapted to be operated, when fluid under pressure is supplied to one side thereof, to effect an application of the brakes and adapted to be operated, upon the venting of lluid from said side, to effect the release of the brakes, and valve means operated upon an increase in the pressure of said reservoir to first limit the amount of fluid vented from said chamber to the reservoir and to then supply fluid from said chamber to operate said application portion to effect an application of the brakes, said valve means being operative upon movement of the equalizing portion to release position for venting fluid under pressure to cause said application portion to operate to effect the release of the brakes.

26. In a fluid pressure brake, the combination with a brake pipe and a chamber charged with uid under pressure, of a reduction chamber, a distributing valve device comprising an equalizing portion subject to the opposing pressures of the brak-e pipe and chamber and operated upon a reduction in brake pipe pressure to service application position for venting fluid under pressure from said chamber to said reservoir and operative upon an increase in brake pipe pressure to a brake releasing position, and also comprising an application portion adapted to be operated, when fluid under pressure is supplied to one side thereof, to effect an application of the brakes and adapted to be operated, upon the venting of fluid from said side, to effect the release of the brakes, a valve having a release position and an application position, said valve when in release position establishing communication through which fluid vented from said chamber flows to said reservoir and when in application position closing said communication and establishing another communication through which4 fluid under pressure is supplied by said equalizing'portion to said side of the application portion, a spring, a movable abutment subject on one side to the pressure of fluid in said reservoir and subject on the other side to atmospheric pressure, and to the pressure of said spring and operative upon an increase in the pressure of said reservoir for moving said valve from release to application position, and means included in said equalizing portion operative in the release position of the equalizing portion for equalizing the fluid pressures on opposite sides of said abutment to permit said spring to act to move said abutment and thereby said valve from application position to release position, and means for venting fluid under pressure from the opposite sides of f said abutment upon movement of the valve to release position.

27. In a fluid pressure brake, the combination with a brake pipe, of a distributing valve device having an application chamber and an application piston chamber, valve means operative to effect an application of the brakes, an application piston in said piston chamber operative upon an increase in the pressure of fluid in the piston chamber for actuating said valve means, valve mechanism operated upon a service reduction in brake pipe pressure for supplying fluid under pressure to both of said chambers and operative upon an emergency reduction in brake pipe pressure for supplying uid under pressure to said piston chamber only, a fluidpressure controlled change-over valve device operable to one position for establishing a communication for connecting said chambers and operableto another position for disestablishing said communication, and a manually operable valve for controlling the operation of the change-over valve device.

28. In a fluid pressure brake, the combination with a brake pipe, of a distributing valve device having an application chamber and an application piston chamber, valve means operative to effect an application of the brakes, an application piston in said piston chamber operative upon an increase in the pressure of fluid in the piston chamber for actuating said valve means, valve mechanism operated upon a service reduction in brake pipe pressure for supplying fluid under pressure to both of said chambers and operative upon an emergency reduction in brake pipe pressure for supplying fluid under pressure to said piston chamber only, a fluid pressure controlled change-over valve device operable to one position Afor establishing a communication for connecting said chambers and operable to another position for disestablishing said communication, means for retarding the flow of fluid to said chambers when the change-over valve device is in the first mentioned position, said means being rendered ineffective to retard the flow of fluid to the application piston chamber when the change-over valve device is in the second .mentioned position, and a manually operable valve for controlling the operation of the change-over valve device.

29. In a fluid pressure brake, the combination With a brake pipe, of a distributing valve device having an application chamber and an application piston chamber, valve means operative to effect an application of the brakes, an application piston in said piston chamber operative upon an increase in the pressure of uid in the piston chamber for actuating said valvey means, valve mechanism operated upon a service reduction in brake pipe pressure for supplying fluid under pressure to a passage'fleading to the application chamber and to another passage leading toward the application piston chamber and operative upon an emergency reduction in brake pipe pressure for lapping the rst mentioned passage, a

Viiuid pressure controlled change-over valve device having two positions, said device functioning in one position to establish communication from the second mentioned passage to the application piston chamber, and functioning in the other position to establish a restricted communication from the second mentioned passage'to both of said chambers, and a manually operative valve device for controlling the positioning ofthe change-over valve device.

30. In a fluid pressurerbrake, the combination With a brake pipe, of a distributing valve device having an application chamber and an application piston chamber, valve means operative to effectan application of the brakes, an application piston inrsai'd piston chamber operative upon an increase Vin the pressure of fluid in the piston chamber for actuating said valve means, valve mechanism operated upon a service reduction in brake pipe pressure for supplying fluid under pressure to a passage leading to the application chamber and to another passage leading toward the application piston chamber and operative upon an emergency reduction in brake pipe pressure for lapping the rst mentioned passage, a fluid pressure controlled change-over valve device having two positions, said device functioning in one position to establish communication from the second mentioned passage to the application piston chamber, and functioning in the other position to establish a communication from the second mentioned passage to both of said chambers, means for retarding the flow of fluid through said communication, said device in the other po,- sition functioning to establish a communication from the second mentioned passage to the vapplication piston chamber, the last mentioned communication by-passing said means, and a manually operative valve device for controlling the positioning of the change-over valve device.

31. In a fluid pressure brake, the combination with ay brake pipe, of a distributing valve device having an application chamber and an applicaequalizing valve device operable upon a service reduction in brake pipe pressure to a serviceapplication position in which said chambers are connected together, valve means operable after saidlequalizing valve device is in service position for supplying fluid under pressure to said connected chambers, said equalizing valve device being operated upon an emergency reduction in brake pipe pressure to emergency position in which said chambers are disconnected from each other and in which fluid under pressure is supplied to the application piston chamber only, and a change-over valve device operable to establish a restricted communication through which fluid supplied by said valve means flows to both of said chambers.

32. In a fluid pressure brake, the combination with a brake pipe, of a distributing valve device having an application chamber and an application piston chamber, valve means operative to` ilzing valve device operable upon a service reduction in brake pipe pressure to a service application position in which said chambers are connected together and operable upon an emergency reduction in brake pipe pressure to emergency position in which said chambers are disconnected from each other and in which fluid under pressure is adapted to be supplied to the application piston chamberl only, Valve means operable after said equalizing valve device is moved to either service position or emergency position for supplying fluid under pressure to both of said chambers or to one of said chambers according to the position of the vequalizing valve device and means operable to a position to` establish a restricted communication through which fluid under pressure is adapted to flow to both of said chambers when the equalizing valve device is in emergency position and operable to a position for disestablishing said communication and for establishing a communication through which fluid flows to the application piston chamber, the last mentioned communication by-passing the restricted portion of the .first mentioned communication.

33. In a fluid pressure brake, in colnbinationa brake pipe, a chamber charged with fluid under pressure, a valve mechanismsubject to the opposingpressures ofthe brake pipe and chamber and operated upon a reduction in brake pipe pressure for supplying fluid under pressure from said chamber to cause an application of the brakes to be effected, means separate from said valve mechanism for controlling communication through which said valve mechanism supplies fluid to apply the brakes, and means for venting fluid from said chamber before fluid under pressure is supplied to effect an application of the brakes.

34. In a fluid pressure brake, the combination with a brake pipe and a chamber charged with fluid under1 pressure, of valve mechanism subject to the opposing pressures of the brake pipe and chamberand operated upon a'reduction in brake pipe pressure for initiating a reduction in the pressure of fluid in the chamber', means separate from said valve mechanism operable for first limiting the reduction in the pressure of fluid in said chamber and for then supplying fluid to cause an application of the brakes tobe effected, and pressure responsivemeans operative upon the operation of the valve mechanism to initiate a reduction in the pressure of fluid in said chamber for controlling the operation of said means. f

35. In aV fluid pressure brake, the combination with a brake pipe and a chamber charged with fluid under pressure, of valve mechanism subject to the opposing pressures of the brake pipe and chamber and operated upon a reduction in brake pipe pressure for initiating a reduction in the pressure of fluid in the chamber, means separate from said valve mechanism operable for flrst limiting the reduction in the pressure of fluid in said chamber and for then supplying fluid to cause an application of the brakes to be effected, and means operative by fluid under pressure vented from said chamber for actuating said means.

36. In a fluid pressureY brake system for a train, in combination, a brake pipe, a chamber charged with fluid under pressure, brake controlling apparatus on the locomotive operative upon a gradual reduction in brake pipe pressure to supply fluid under pressure from said chamber for effecting a service application fof the brakes on the locomotive and upon a sudden Vreduction in brake pipe pressure for effecting an emergency application of ,the brakes on the locomotive, means operative in effecting aA service application of the brakes to reduce the pressure of fluid in said chamber an amount commensurate with the amount of reduction in the pressure of fluid in the auxiliary reservoir of a car of the train in taking up the lost motion in the car brake for causing the brakes on the locomotive to be applied in synchronism with the brakes on the cars of the train, and means operative in effecting an emergency application of the brakes for cua-sing the brakes on the locomotive to be applied at a rate not exceeding the emergency rate of an application of the brakes on the cars or the train.

37. In a uid pressure brake system for a rail- Way train, in combination, a brake pipe, a brake cylinder, a chamber charged with fluid under pressure, a brake controlling apparatus on the locomotive operative uponA a gradual reduction in brake pipe-pressure to supply fluid under pressure from said chamber Afor effecting a service application of the locomotive brakes and upon a sudden reduction in brake pipe pressure for effecting an emergency application of the locomotive brakes, means operative inA effecting a service application of the brakes to reduce the pressure of Vfluid in said chamber an amount commensurate with the amount-of reduction in the pressure of fluid in the auxiliary reservoir of a car of the train in taking up the lost motion in the car brake for causing the brakes on the locomotive to be applied in synchronism with the brakes on the cars of thetrain, and means operative in effecting an emergency application of the brakes for causing a build up in pressure in said brake cylinder at a rate not exceeding the emergency rate at which the brake cylinder pressure is built up on I,cars of the train.Y

- 38. In a fluid pressure brake system for a rail- Way train, in combination, a brake pipe, a brake cylinder, a chamber' charged with fluid under pressure, a brake controlling apparatus on the locomotive operative upon a gradual reduction in brake pipe pressure for supplying fluid under pressure from said chamber to cause the brake cylinder to effect a service application of the locomotive brakes and upon a sudden reduction in brake-pipe presure for supplying fluid under pressure from said chamber toy cause the brake cylinder to effect an emergency application of the locomotive brakes, means operative with the brake controlling apparatus in service application position to reduce the pressure of fluid in said chamber an amount commensurate with the amount of reductio-n in the pressure of fluid in the auxiliary reservoir of a car of the train in taking up the lost motion in the car brake for causing the brakes on the locomotive to be applied in synchronism with the brakes on cars of the train, and means operative with the brake controlling apparatus in emergency application position for retarding the rate of build up in pressure in the brake cylinder so as not to exceed the rate of brake cylinder pressure build up on cars of the train.

39. vIn a fluid pressure brake system for a railway train, in combination, a brake pipe, a brake cylinder on the locomotive, a' chamber charged with fluid under pressure, a brake controlling apparatus subject to the opposing'pressures of the brake pipe. andl chamber and operative upon a gradual reduction in brake pipe pressure for initiating a reduction in the pressure of fluid in said chamber and operative upon a sudden reduction in brake ypipe pressure for supplying fluid under pressure from said chamber to cause the operation of the brake cylinder to effect an emergency application of the locomotive brakes, means operative when the pressure of fluid in said chamber has been reduced an amount commensurate with the amount of reduction in the auxiliary reservoir pressure on a car of the train in taking up lost motion in the car brake for limiting the reduction in the pressure of fluid in the chamber and for supplying fluid under pressure from said chamber to cause the operation of the brake cylinder to effect a service application of the locomotive brakes, the reduced fluid pressure in said chamber and the action of said means causing the brakes on the locomotive to be applied in synchronism with the brakes on cars of the train, means operative in effecting an emergency application of the brakes for retarding the rate of increase in brake cylinder pressure so as not to exceed the rate of increase in brake cylinder pressure on cars of the train, and means included in the brake controlling apparatus for rendering the first mentioned means ineective to control the supply of fluid under pressure in effecting an emergency application of the brakes.

40. In a fluid pressure brake system for a railway train, in combination, a brake pipe, a brake cylinder, a chamber charged with fluid under pressure, a brake controlling apparatus on the locomotive operative upon a gradual reduction in brake pipe pressure for supplying fluid under pressure from said chamber to cause the brake cylinder to effect a service application of the locomotive brakes and upon a sudden reduction in brake pipe pressure for supplying fluid under pressure to cause the brake cylinder to effect an emergency application of the locomotive brakes, means operative With the brake controlling apparatus in service application position to reduce the pressure of fluid in said chamber an amount commensurate with the amount of reduction in the pressure of fluid in the auxiliary reservoir of a car of the train in taking up lost motion in the car brake for causing the brakes on the locomotive to be applied in synchronism with the brakes on cars of the train, means operative with the brake controlling apparatus in emergency application position for retarding the rate of build up in pressure in the brake cylinder so as not to exceed the rate of brake cylinder pressure build up on cars of the train, and means for rendering ineffective the means for controlling the brake cylinder build up on the locomotive in emergency.

4l. In a fluid pressure brake system for a railway train, in combination, a brake pipe, a brake cylinder, a chamber charged with fluid under pressure, a brake controlling apparatus on the locomotive operative upon a gradual reduction in brake pipe pressure for supplying fluid under pressure from said chamber to cause the brake cylinder to effect a service application of the locomotive brakes and upon a sudden reduction in brake pipe pressure for supplying fluid under pressure to cause the brake cylinder to effect an emergency application of the locomotive brakes, means operative with the brake controlling apparatus in service application position to reduce the pressure of fluid in said chamber an amount commensurate with the amount of reduction in the pressure of fluid in the auxiliary reservoir of a car of the train in taking up lost motion in the car brake for causing the brakes on the locomotive to be applied in synchronism with the brakes on cars of the train, means operative With the brake controlling apparatus in emergency application position for retarding the rate of build up in pressure in the brake cylinder so.

as not to exceed the rate of brake cylinder pressure build up on cars of the train, fluid pressure controlled means for rendering ineffective the means for controlling the brake cylinder build up 'in emergency, and means operative to control the pressure of fluid acting on the fluid pressure controlled means.

42. In a fluid pressure brake system for a rail- Way train, in combination, a brake pipe, a brake cylinder, a chamber charged with fluid under pressure, a brake controlling apparatus on the locomotive operative uponV a gradual reduction in brake pipe pressure for supplying fluid under pressure to `cause the brake cylinder to effect a service application of the locomotive brakes and upon a sudden reduction in brake pipe pressure for supplying fluid under pressure from said t chamber to cause the brake cylinder to effect an emergency application of the locomotive brakes, means operative with the brake controlling apparatus in service application position to reduce the pressure of fluid in said chamber an amount commensurate With the amount of reduction in the pressure of fluid in the auxiliary reservoir of a car of the train in taking up lost motion in the car brake for causing the brakes on the locomotive to be applied in synchronism with the brakes on cars of the train, means operative with the brake controlling apparatus in emergency application position for retarding the rate of build up in pressure in the brake cylinder so as not to exceed the rate of brake cylinder pressure build up on cars of the train, fluid pressure controlled means for rendering ineffective the means for controlling Vthe brake cylinder build up in emergency, and a manually operative f valve device for controlling the operation of said fluid pressure controlled means.

43. In a fluid pressure brake, in combination, a brake pipe, a chamber charged with fluid under pressure, a brake controlling valve mechanism subject tothe opposing pressures of the brake pipe and chamber and operative upon a reduction in brake pipe pressure for initiating a reduction in the pressure of fluid in said chamber, means operative to rst limit the reduction in the pressure of fluid in said chamber to an amount commensurate with the amount of reduction in the pressure of fluid in the auxiliary reservoir of a car of a train in taking up the lost motion in the car brakes, and to then supply fluid under pressure from said chamber to effect an application of the brakes, and means separate from the brake controlling valve mechanism and set in operation upon the operation of the brake controlling valve mechanism for controlling the operation of the first mentioned means.

ELLIS E. HEWITT.

Images