US1991889A - Train control apparatus - Google Patents

Description

Feb. 19, 19 35. c C FARMER ET AL 1,991,889

TRAIN CONTROL APPARATUS Original Filed Feb. 15, 1924 5 Sheets-Sheet 1 INVENTORS CLYDE c. F'ARMER AND THOMAS HTHOMAS ATTORNEY Feb. 19, 1935. c. c.- FARMER ET AL. 1,

TRAIN CONTROL APPARATUS Original Filed Feb. 15, 1924 5 speets-sheet 2- lNVENTOR cwoz c FARMER THoMAs CCT oMAs ATTORNEY Feb. 19, c FARMER ET AL TRAIN CONTROL APPARATUS Original Filed Feb. 15, 1924 5 SheetsSheet 5 19 INVENTOR CLYDE g r RMER THOMAAS HTHOMAS ATTORN Patented Feb. 19, 1935 UNITED, STATES ATE OFFICE Clyde C. Farmer, Pittsburgh, and Thomas H. Thomas, Edgewood, Pa., assignors to The Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application February 15. 1924, serial No. 692,970

Renewed November 3, 1926 53 Claims. (01. sor -1s) This invention relates to an automatic train means for cutting the two stage brake pipe reducspeed control equipment adapted to control the tion feature out of action under certain condispeed of the train in accordance with the signal tions. l I indication. 1 v I p Another object ofour invention is to provide 5 ,'Although a train may be equipped with anaumeans for ensuring that when the engineer ma- .5

tomatic speed control apparatus for automatically nipulates the brake valve to effect a reduction in controlling the'speed in accordance with thesigbrake pipe pressure,v he must make a predeternal indication, it is considered desirable to ensure mined reduction in brake pipe pressure, or the that the engineer is attending to his duties at all train control apparatus. will act,

times and it is therefore desirable to compel the Another objectis to provide means for prevent- 1 0 engineer, under penalty, to keep the speed of the ing the train. control apparatus from acting, if train within the speed limit required by the sigthe engineer makes a predetermined reduction nal indication, by his own acts. inrbrake pipefpressure within a predetermined Accordinglymne, feature of our invention conperiod of time.

' l5 sists in providing a train speed control equip- Another object is to provide means for preventv ment, in which, when the signal indication ing'failure ,to function properly due to possible changes from a more favorable to a less favorleakagepast the equalizing discharge valve when able condition, the engineer will be required, unsaid valve'is in its closed position.

der penalty, to make an application of the brakes Anotherobject'is to provide means for permitsuflicient to bring the speed of the train down ting the use of fluid in the train control appara- 20 toor below the speed limit as indicated by the his at a predet rmi Pressure 1655 than the signal indication and furthermore, he must also main reservoir pres while at e Same e acknowledge the signalindication, under certain p ovid o 11 of main reservoir Pressure conditions, even if the speed of the train in passat the brake valve, in order to avoid the deposit i signal indication is below the speed limit and condensation of moisture in the train control 25 quired by the signal indication. apparatus.

It is well known that a train, particularly a I Another object is to provide an improved brake long train, can be handled more smoothly by valve device for use in .connectionwith a train making a graduated rather than a continuous Control. q p a r 3 application of the brakes, since when a heavy, A t e j c s o generally p y e Y continuous reduction in brakepipe pressure is train c ntr l p ra s to reduce he num effected, there is danger that the brakes will be h r fw rk ns parts to a m. i i applied at the head end of the train before they ot er Obj cts a advantages Will be'apparent are applied at the rear end, and with suchforce in the following more deta d description of th 35, as to cause the slack of the train to run in harshly invention. a i and thus cause dangerous shocks, In the accompanying drawings; Fig. l is a To prevent this, it has been the practice to first diagrammatic view, partly in section, of an automake a light reduction in brake pipe'pressure, Ina-tic train speed control equipment embodying and then, after moving the brake valve handle our improvements; Fig. 2 a central sectional 40 to lap position and holdingthe same there, until view of the brake application [valve unit of the 40 the brake pipe exhaust ceases, to effect a-further train control equipment; Fig. 3a diagram illusheavier reduction in brake pipe pressure. This trating the operation when a medium speed method of applying the brakes is known as a signal indication is received; and Fig. 4 a diasplit reduction or two application stop. a gram illustrating the operation when a low 5 The same condition would obtain where the speed signal indication is received. reduction in brake pipe pressure to effect an ap- In general, the train control equipment may plication of the brakes is made by the operation comprise a governor valve unit, a brake applicaof an automatic train control equipment and tion valve unit, a brakevalve device 1, and an therefore another feature of our invention conacknowledging valve device 2.

sists in providing means associated with an au-' The governor valve unit may comprise a'cen- 59 toniatic train control equipment for automatitrifugal governor portion 3, a change speed valve cally effecting a two stage reduction in brake portioni'atiming portion 5, and a magnet and pipe pressure when the train control apparatus pipe bracket portion 6. The governor portion operates to eifect an application of the brakes. 3 comprises a rotatable member 7 having a pinion Anotherfeature of our invention is to provide 8 meshing with a pinion 9, the pinion 9 being .5-

operatively connected with a locomotive axle so as to rotate at a speed which varies according to the speed of the train. The member 7 carries governor balls 10 adapted to operate a spindle 11 in accordance with the speed of the train. A cross head 12 is carried by the spindle 11 and is adapted to operate a series of governor valves 13, 14, and 15, and blow down timing valves 16 and 1'7.

The change speed valve portion 4 comprises a casing containing a high speed valve device, a medium speed valve device, and an acknowledging pilot valve device.

The high speed valve devicecomprises a piston 18 contained in piston chamber 19 and a slide valve 20 contained in valve chamber 21 and adapted to be operated by piston 18. The medium speed valve device comprises a piston 22 contained in piston chamber 23 and a slide valve 24 contained in valve chamber 25 and adapted to be operated by piston 22. The acknowledging pilot valve device may comprise a piston 26 con,- tained in piston chamber 265, a valve piston 27 contained in valve chamber 28, and a valve 29 contained in valve chamber 30, said valve piston 2'7 and the valve 29 being operable by piston 26.

The timing portion 5 comprises a casing containing a high to medium speed timing valve device and a medium to low speed timing valve device. The high to medium speed timing valve device comprises a flexible diaphragm 31 subject on one side to the pressure in diaphragm chamber 32 and on the opposite side to the pressure of a coil spring 33, and a double beat valve 34, contained in valve chamber 35 and operable by the diaphragm 31. The'medium to low speed timing valve device comprises a flexible diaphragm 36, subject on one side to the pressure in a diaphragm chamber 37 and on the opposite side to the pressure of a coil spring 38, a valve 39 contained in spring and valve chamber 40, and a valve 41 contained in valve chamber 42, said valves being operable by the diaphragm 36.

The magnet and pipe bracket portion 6 comprises a casing to which all the controlling pipes of the governor unit are connected and containing a high speed magnet valve device and a medium speed magnet valve device. The high speed magnet valve device comprises a magnet 43 and valves 44 and 45 operable by said magnet. The medium speed magnet valve device comprises a magnet 46 and valves 4'7 and 48 operable by the magnet 46.

The brake application valve unit comprises a pipe bracket portion 49, a brake pipe reduction ensuring and brake application suppressing portion 50, a brake application portion 51, a split reduction cut-out portion 52, and an equalizing discharge valve portion 53.

The pipe bracket portion 49 comprises a casing to which all of controlling pipes of the brake application valve unit are connected and containing a first reduction reservoir 54, a second reduction reservoir 55, and timing reservoir No. 1, and a timing reservoir No. 2.

The brake pipe reduction ensuring and brake application suppressing portion 50 comprise a casing containing a brake pipe reduction ensuring valve device and a brake application suppressing valve device. The brake pipe reduction ensuring valve device may comprise a flexible diaphragm 56 subject to the opposing fluid pressures in diaphragm chambers 57 and 58, and adapted to operate valves 59 and 60 contained in valve chamber 61. The brake application suppressing valve device may comprise a flexible diaphragm 62, subject on one side to the pressure in diaphragm chamber 63 and adapted to operate valves 64 and 65 contained in valve chamber 66.

The brake application portion 51 comprises a casing containing a brake application valve device, a pilot piston valve device, a reduction timingvalve device, and a reduction hold back valve device. The brake application valve device may comprise a piston 67 contained in piston chamber 68, and a slide valve 69, contained in valve chamber '70 and adapted to be operated by piston 6'1. The pilot piston valve device may comprise a piston 71, contained in piston chamber 72 and a slide valve '73, contained in valve chamber 74,

and adapted to be operated by piston '71.

The reduction timing valve device may comprise-a piston '75 subject onone side to the pressure in piston chamber '76 and a valve 7'1, contained in the valve and piston chamber 78 and adapted to be operated by piston'75. The reduction hold back valve device may comprise a piston '79, subject on one side to the pressure in piston chamber 80, and a valve 81, contained in valve chamber 82 and adapted to be operated by piston '79. r

The split reduction'cut-out'portion 52 contains a piston'83, contained in piston chamber 84, and a slide valve 85, contained in valve chamber 86 and adapted to be operated by piston 83. The equalizing discharge valve portion 53 contains an equalizing discharge valve mechanism comprising a piston 87 having a chamber 88 at one side connected through pipe and passage 89 to an equalizing reservoir 90, and a valve 91 contained in chamber-92 at the opposite-side of the piston and adapted to be operated by said piston.

The portion 53 also contains a reduction safety valve device comprising a flexible diaphragm 93, subject on one side to the pressure in diaphragm chamber 94, and a valve 95, contained in valve and diaphragm chamber 96, and adapted to be operated by said diaphragm.

The brake valve device 1 may comprise an upper casing section, a lower casing section and an intermediate casing section and contained in the intermediate casing section is a valve chamber 97 containing an upper rotary valve 98 and a lower rotary valve 99, both adapted to be operated by handle 100. The upper casing section contains a release valvedevice comprising a piston 101 subject on one side to the pressure in piston chamber 102, and a valve 103, contained in valve chamber104 and adapted to be operated by piston 101. The acknowledging valve device 2 may comprise a casing having a valve chamber 105 containing a rotary valve 106 adapted to be operated by handle 107. Y

The equalizing discharge valve mechanism for the brake valve device'is also the equalizing discharge valve mechanism of the train control apparatus and is associated with the brake application valve unit, as hereinbefore described.

With the brake valve inrunning. position, as shown in Fig. 1, the brake pipe 108 is maintained charged to the standard pressure from the main reservoir 109, from which fluid flows through pipe and passage 110 to valve chamber 70 and thence, with the slide valve 69 in the normal release position as shown, through pipe and passage 111 to the rotary valve chamber 9'1 01 the brake valve device. In running position, fluid issupthe usual pressure reducing feed valve device 113to the brake pipe 108 by way ofcavity 114 rotary valve 99.

The brake pipe 108 is connected-win the usual manner to the, piston chamber 92 of the equalizdischarge, valve mechanism and, is'also' connected to thediaphra'gm chamber 58 of the reduction ensuring valve device.

.A suppression limiting. reservoir 115 is com .nected' to pipe and passage 116 which leads to through pipe 120 and cavity 121 in. the rotary valve 98 with an atmospheric exhaust 122..

. The equalizing reservoir 90 and the piston chamber 88 of the equalizing discharge valve mechanism are charged to brake pipe pressure by way of, cavity 123. in the rotary valve 99, pipe and; passage 124, and cavity 125 in application slide valve 69.

The valve chamber 74 of the pilot valve device charged with fluid at a pressure less than main reservoir pressure by way of a feed or reducing valve device 126 andpipe and passage 127. The valve chamber 86 of the split reduction cut-ofi valve device is. also charged with fluid from passage127, as well as the piston chamber 105 of the acknowledging valve 2.

Assumingthat the train is running under a high speed signal indicationthe high speed magnet 43 will be energized and the medium speed magnet 46 deenergized. The valve 44 will then be seated and the valve 45 unseated so as to supplyfiuid atfeedvalve pressure from pipe 127 to passage 128, leading to piston chamber 190f the high speed valve device, and since the valve chamber 21 is also charged with fluid from the pipe and passage 127, the piston 18 will be held in its inner position by spring 129. In this position, the slide valve 20-opens communication from. valve chamber 21 through passage 130 to diaphragm chamber 32 of the high to mediuni timing valve device and to the highto medium reservoir 131, so that said chamber and reservoir are charged-with fluid .atfeed valve pressure.

'Ihe diaphragm31 then moves the valve 34 to close communication from passage 132 to passage 133. Passage 132 leads from piston chamber 72 of the pilot valve device past the open valve 64 of the application suppressing valve device and passage 133 leads to the medium speed governor valve 13, so that communication is now out off from the pilot piston 71 to the medium speed governor valve 13.

In the high speed position of slide valve 20, the diaphragm chamber 37 of the medium to low timing valve device and the medium to low reservoir 134 are also charged, with feed valve pressure from valve chamber 21 through port 135 in slide valve 20 and passage 136, so that diaphragm 36- is operated to close valve 39. and open valve 41. Fluidat'feed valve pressure is then supplied from feed valve passage 127 to passage 137, leading'to the piston chamber 23 of themedium speed valve device; The. medium speed piston 22 being thus subject to feed valve pressure on its opposite sides, the piston will be shifted to its inner position by spring 138. In this po sition, the slide valve 24 connects the stop resera voir 139-through passage 140 and cavity 141 in slide valve 24. with an atmospheric exhaust port.

With the'train running at a speed above the .mediumspeed limit, the speed governor will operate the cross head 12 so that the medium speed governor valve 13 will be open, connecting pipe and'passage' 133 to the atmosphere. Pipe and passage 133' leads to piston chamber 84 of the split reduction cut-out. valve device, so that piston 83 will be shifted to its outer position by feed valve pressure in valve chamber 86. In this position, the slide valve 85, through cavity 142, connects passage 143, leading to the second reduction reservoir 55 With'passage 144 leading to-the first reduction reservoir 54, so that the two reservoirs operate as a singlereservoir, the split reduction feature, to be hereinafter described, being thus cut out of action, passage 144 is connected to exhaust, port 149 through. a port in slide valve 69, when the application piston 67 is in itsnormal release position, so that both reduction reservoirs 54 and 55 are now maintained at atmospheric pressure.

The pipe and passage 132 is connectedto the high speed governor valve 15, so that if'the speed of the train should exceed the high speed limit, the speed governor will operate the cross head 12 to open the high speed valve 15. When valve 15 is opened fiuidunder pressure is vented'to the atmosphere from pipe and passage 132 and the piston chamber 72 of the pilot valve device, causing the movement of piston] 71-" to its outer position by feed valve pressurerin valve chamber 74. In this position, communication from "valve.

chamber 70 through passage 145, cavity 146 and passage 147 leading to piston chamber'68 is cut off, and passage 147 is connected through said 90 and the equalizing discharge piston chamber 1 88 withpassage 144, leading to the first reduction reservoir 54, I

The port 150 includes a restricted portionl51 corresponding with the usual preliminary discharge port of the standard brake valve, so that iluidisvented from the equalizing reservoir at the same rate as would be the case with a brake valve when moved to service application position. The combined volumes of the first and the second reduction reservoirs are such that the equalizing reservoir pressure upon equalization into the reduction reservoirs will correspond with a full, service reduction in brake'pipe pressure which would be twenty-five poundswith a standard brake pipe pressure of seventy pounds.

The piston 87 is operated by the reduction in equalizing reservoir pressure to open the discharge valve 91, so that fluid is vented from the brake pipe 108 to a passage 152, leading to piston chamber 76 of the reductiontiming valve device. Piston 75 is then shifted outwardly, so that an exhaust passage 153 having a restriction 157, is opened to chamber 76. Fluid is also vented from the brake pipe byway of passage 154 containing a non-return check valve 155 and a restricted exhaust port 156, and the exhaust passage ;152 is also connected through a passage 158 in the application slide valve'69 containing a restricted port 159 with exhaust port- 149.

, The areas of the three restricted exhaust, ports charge from the brake pipe is'equal to that produced when the equalizing discharge valve is fully opened in the standard brake valve. The pressure of fluid vented from. the brake pipe through passage 154 acts in chamber 94 of the reduction safety valve device, so that diaphragm 93 is moved upwardly to close the valve 95.-

Thebrake pipe'pressure will continue to reduce by operation of the discharge valve 91 until a full service application'of the-brakes has been effected or until the speed of the train has been reduced below the high speed limit. If the speed of the trainhas been'reduced below the high speed limit, the high speed governor valve 15 will close and the engineer'may release the brakes by turning the brake valve handle to lap position for a short period and then to release position. When the application slide valve 69 is moved to application position, a pipe and passage 160, leading to the valve chamber 104 of the release pilot valve device is connected, through cavity 161, with passage 132.

In running position of the brake valve, fluid under pressure is supplied through a port 162 to piston chamber 102, so that the piston 101 operates to hold the valve 103 open, connecting passage 160 with the atmosphere.

As a consequence, so long as the brake valve remains in running position, the passage 132 and piston chamber '72 of the pilot piston valve device will be open to the atmosphere, even though the high speed governor valve 15 should close and the pilot piston 71 will be maintained in its brake applying position.

When the engineer moves the brake valve handle'to lap position, the piston chamber 102 is vented to the atmosphere, permitting the valve 103 to move so as to cut ofi the exhaust through passage 160. The pressure in piston chamber '72 can then build up by equalization through port 163 in piston 71, permitting spring 164 to shift piston '71 back to release position.

In this position, fluid is supplied from valve chamber '70 through passage 145, cavity 146, and passage 147 to piston chamber 68, thus equalizing the fluid pressures on opposite sides of piston 6'7 and permitting spring 165 to shift piston 67 to release position. The engineer can now release the brakes by moving the brake valve to release position, in which the brake pipe is recharged in the usual manner.

If the signal indication be changed from high speed to medium speed and the train is running at a speed exceeding the medium speed limit, the indication should be acknowleded at once by the engineer making a full service application of the brakes to reduce the speed of the train below the medium speed limit, it being noted that under the above conditions the acknowledging valve handle 10? need not be operated.

If the engineer fails to acknowledge the signal indication by making a full service application of the brakes, and if the full service reduction in brake pipe pressure is not effected in a predetermined time, the train control apparatus will then operate to produce an application of the brakes.

When the engineer moves the brake valve to service application position, the upper rotary valve 98 connects pipe 116, through a cavity in the rotary valve, with pipe 120, so that fluid is vented from the normally charged suppression reservoir to the reduction reservoir 119, which is now at atmospheric pressure. The pressures .157, 156, and 159 are such that the rate of disin the two reservoirs equalize at a predetermined pressure, say fifty pounds, when the standard brake pipe pressure is seventy pounds, so that the reduction in pressure amounts to twenty pounds.

The pipe and passage 116 'is connected 'to'the diaphragm chamber 57 of the reduction ensuring valve device so that the pressure in said chamber is also reduced twenty pounds. In service position of the brake valve, pipe 124 is connected, through a cavity in thelower rotary valve 99 with an atmospheric exhaust port,v so that fluid is vented from the equalizing reservoir 90 and the piston chamber 88 of the equalizing discharge valve mechanism by way of passage 89, cavity 125 in application slide valve 69' and pipe 124;" The reduction in pressure in the reservoir causes the movement of the equalizing piston 87 by the higher brake pipe pressure acting in chamber 92, so that the valve 91 is opened to discharge fluid under pressure from the brake pipe 108 and thereby effect an application ofthe brakes. I

Fluid is vented from the brake pipe by the opening of the discharge valve 91 through passage 152 to piston chamber '76'of the reduction timing valve device. Piston 75 is operated to close the valve 77 and uncover port 153 so that fluid is vented at this point at a rate determined by the restricted port 157. Fluid is also vented through passage 154, past the check valve 155mm outet the restricted atmospheric port 156. From passage 152, the discharge from the brake pipe flows through a cavity 166 and passage 167 past check valve 168 to chamber 63 of the application suppressing valve device and thence to timing reservoir No. 2 and valve chamber ,61 byway 0! pasage 169. The pressure in chamber 5'1being the reduced suppression reservoir pressure, the higher brake pipe pressure in chamber 58 holds the diaphragm 56 in its lower position, opening the 'valve 59 and seating valve 60. Fluid is therefore vented from passage 169 past the valve 59 through a restricted exhaust port 170.

The venting of fluid from the brake pipe to chamber 63 causes the upward movement of diaphragm 62, so as to unseat'valve 65 and seat the valve 64. The seating of 'valve 64 cuts '08 communication through passage'132, so that the pilot piston 71 is cut oif from the medium speed governor valve 13 and thus the operation or the pilot valve device and the application valve device is prevented so long as the valve 64 of the application suppressing valve device remains seated.

If the brake pipe pressure is reduced 9. predetermined amount, preferably a full service reduction, or about twenty-five pounds, where the standard brake pipe pressure is seventy pounds, the brake pipe pressure in chamber 58 being slightly less than the suppression reservoir pressure in chamber 57, the diaphragm 56 will be operated to open valve 60 and close valve 59;. The closing of valve 59 cuts off the venting or fluid from the chamber 63 and the timing reser voir No. 2, so that the pressure therein is bottled up and the diaphragm is held in position to muntain the valve 64 closed, thus preventing the'operation of the pilot piston valve device.

When the reduction ensuring valve device has been operated upon a predetermined reduction in brake pipe pressure to close the valve 59, the valve 60 will be unseated, so that hold under pres sure will then be supplied from the brake pipe to the chamber 63 by way of passage 108, past the open valve 60, to passage 169 and thence through gee-gees a "by pass around the check valve 168 teem-mber 63. The pressure in chamber "63 will thus be maintained after the equalizing discharge valve 91 is closed and thereby the suppressing valve device will be maintained in its suppressing position, so long as the brakes, remain applied.

If the reduction in brake pipe pressure is less than the predetermined amount, then when the discharge valve 91 closes, since the discharge of fluid from the brake -pipe is cut oil, the pressure in chamber 63 and in the timing reservoir No. 2 will bleed down through the restrictedport and after a predetermined short period of time, the diaphragm will be permitted to move downwardly and the valve 64 will be opened to establish communication through the passage 132.

If under the above condition, the speed of the train exceeds'the medium speed limit, the pas sage 132 will be connected to the 'open'medium speed governor valve 13 as follows.

Upon receiving a medium speed signal indication, the high speed magnet 43 "will be deenergized and the medium speed magnet 46 energized. When the high speed magnet 43 is deene'rgize'd, the valve 45. will be seated and thev valve 4'4 opened, so-that fluid is vented from piston ch'anrber'19 of the high speed piston 18,.through pas-;

sage 128 to the atmospheric exhaust controlled by valve 44'. I'he'high speed piston 18 consequently shifts the valve'20 to its outer position.

The energiz'ation of the medium speed magnet 46 operates to close the valve 47 and open the valve 48, so that passage 136 leading to chamber 37 of the medium to low timing valve device and to the' medium to low timing reservoir 1 34 is connected with feed valve pas's'ag'e 127 through cavity 1'71 in slidevalve 20 and passage 1'72. The me'dium'to low speed timing reservoir 134 and chamber 37 of the medium to low timing valve deviceare thus maintained charged with fluid at feed valve pressure while the train control apparatus is operating under a medium speed signal indication. V

In the outer position of :the slide valve 20,-the high to medium reservoir 1-31 and the chamber 32 of the high to medium timing valve device are connected to the high tomedium blow down timing valve 16 by way of passage 130, cavity 1'73 in slide valve 20 and passage 174.

When the pressure in the reservoir 131 and chamber 32 has been reduced to a predetermined degree, dependent on the speed of the train and the consequent size of vent opening created by the valve 16, the diaphragm 31 will be operated so as to cause the double beat valve 34 to open communication from passage 132 to passage 133. This establishes. communication from the pilot piston chamber '72 to the medium speed governor valve 13, and if the speed of the train exceeds the medium speed limit, the valve 13 will be as hereinbefore described in connection with a trainrunningin a high speed block and exceeding the high speed limit.

It will thus be seen that if the engineer makes a service application of the brakes 'but fails to make a full service reduction in brake pipe pressure, theautomatic train control apparatus will be cut in and will operate to effect a-further reduction in brake lpipe pressure, providedthe train is at a high speed exceeding the medium speed limit. In fact, when the brakes are ap plied 'by'operation of the train control appamatus as above described, a full service reduction in brake :pipe pressure is made in addition to what 'viding the timing reservoir No.2 which functions as follows: When the first reduction in brake pipe pressure is made by the engineer and as soon as the discharge from the brake pipe ceases through the closing of the discharge valve 91,- the valve 59 will remain open, since the reduction in brake pipe pressure has not been suflic'ient to' effect the movement of the diaphragm 56 to close the valve 59 but the diaphragm 62 will not be immediately. operated, because said diaphragm will remain in its upper position, until the pressure in the timing reservoir No. 2 and in cha'mb'er 63 has been reduced by escape through the restricted port 170. The delay in the operation of diaphragm 62 is suflici'ent to permit the engineer to move the brake valvehandle from lap position afterthe first reduction in brake pipe pressure ceases, back to service position, for the purpose of effecting thesecond reduction in brake pipe pressure and if the second reduction in brake pipe pressure is sufficient to produce a full service reduction in brake pipe pressure the operation of the train control apparatus to efiect an application :of the brakes will be suppressed.

If the engineer does not make the second reduction in brake pipe pressure within the time permittedby the venting of pressure fromthe'timing reservoir No. 2 and to a degree correspending with afull' servioeapplication of the brakes; the train control apparatus will function, as will 'be understood. I

It will be further understood that should the engineer fail to makeany brake application, the train control apparatus will functionas hereinbefore'des'cribed'if the speed exceeds the medium speed limit, to effect arr-application of the brakes.

If the brake application is produced by the operation of the traincontrol apparatus instead of by the engineer manipulating the brake valve, a delay penalty is imposed by requiring a longer time-to'effect the release of the brakes. This is due to-the fact that when the train control apparatus functions, the pipe and passage 132 is vented by the unseating of the medium speed valve 13 and beforethe brakes can be released, the medium speed valve must close and the pipe and passage 132 must be recharged. The additional time required to recharge the pipe 132 before the brakes can be released provides the time penalty, when the engineer fails to apply the brakes upon passing a signal indication set at medium speed,

The passage 132 is recharged through the restricted port 163 in piston 71 and also by way of a restricted port leading from the feed valve passage 127 to passage 132. V

In order to release the brakes after thebrakes have been applied by operation of the train control apparatus, the brake valve handle mustfirst be-moved to lap position, in which the supplyof fluid to the chamber 102 of the release pilotvalve device is cutoff and said chamber is "connected to the exhaust through a cavity in the upper rotary valve 98. The piston 101 then shifts the valve 103 to its seat, cutting off the exhaust port 176 from the,passage 160. Passage 160 is connected in the application'position of application slide valve 69 through cavity 161 with passage 132, so that closing the exhaust port 176 permits the passage 132 to be recharged as soon as the medium speed governor valve 13 closes.

.When the passage. 132 has been recharged and the application valve device has been returned to release position by the movement of the pilot valve device to release position, the brake valve handle may be moved to release p0sition,,so as to recharge the brake pipe and thus effect the release of the brakes.

When the speed of the train is below the medium speed limit, the medium speed governor valve 13 will be closed and the passage 133 being out 01f from the atmosphere, fluid pressure equalizes through a restricted port 177 in the piston 83 of the split reduction cut-out valve device to the piston chamber 84, permitting spring 178 to move piston 83 and valve to their inner position, in which the split reduction feature is out in, as will be hereinafter described.

-When a trainv receives a low speed signal indication, the engineer, upon noting the change in the signal indication should move the acknowledging valve device handle 107 to acknowledging position, and should make an application of the brakes to reduce the speed of the train below the low speed limit and this action must be effected within a predetermined period of time as determined by the blowing down of the medium to low reservoir pressure.

With the acknowledging handle 107 in its normal position, as shown in Fig. 1, the acknowledging reservoir 179 will be connected, through a cavity 180 in the rotary valve 106, with feed valve pipe 127, so that said reservoir is normally charged with fluid under pressure. When the handle 107 is turned to acknowledging position, the reservoir 179 is connected, through a cavity in the rotary valve 106, with pipe and passage 181, communication through which is established byway of cavity 182 in the application slidevalve 69 when said valve is in release position.

Fluid under pressure is then supplied through pipe and passage 181 to piston chamber 26 of the acknowledging pilot valve device and the piston 26 is shifted to its inner position, opening the valve 29 and causing the valve piston 27 to cut off communication from passage leading to stop reservoir 139 to the seat of slide valve 24. The opening of valve 29 permits flow of fluid under pressure from valve chamber 21, which is connected by passage 183 with chamber 30, to passage 140, so that the stop reservoir 139 is charged with fluid under pressure.

The piston chamber 26 is connected to the atmosphere through a restricted port 184, of such size that the chamber 26* and the acknowledging reservoir 179 will blow down in a predetermined period of time, such as thirty seconds. After the pressure has been reduced, the piston 26 will return to its normal outer position. The result of acknowledging the low speed signal indication will depend upon the speed of the train at the time the signal indication is received.

Before describing the results of acknowledging or not acknowledging when a low speed indication is received we will describe the general operation of the apparatus upon receiving a low speed signal indication; Referring more particularly to thediagram; Fig. 4, when a low speed indication is received, the medium speed magnet 46 is deenergized, and the high speed magnet 43 will remain deenergized, as-it was under a medium speed indication.

The high speed piston 18 willthereiore remain, in its outer position, as was the case when under a medium speed indication and the medium speed magnet 46 being deenergized, the valve 48 will be seated and the valve47. opened, the chamber 37 of the medium to low timing valve device and the medium to low reservoir 134 will be be 'connected to the medium to low blow down timing valve 17 by way of passage 136, cavity 171 in slide valve 20, and through passage 172, past the open valve 47 to the blow downvalve 17. When the pressure in the reservoir 134 has been blown down to a predetermined degree, dependent upon the speed of the train and the consequent size of the vent openingcreated by the. operation of valve 17; the diaphragm 36 will be operated, so that the valve 41 will close and the valve 39 open. Fluid is then vented from piston chamber 23 through passage'l37 past the open valve 39 to the atmosphere, and the'medium speed piston 22 will be shifted to its outer position, moving valve I 24 to its outer position. r

In this position, the low speed governor valve 14 is connected to pipe and passage 132 through passage 184 and cavity 185 in slide valve '24. Passage 132 contains a check valve 186 for preventing flow through said passage in one direction.

Cavity 185 also connects passage 132 with pas sage 140, so that if the acknowledging piston 26 has not been moved by the engineer acknowledging the signal indication, the passage 132 will be connected to the stop reservoir 139.

If the engineer fails to acknowledge the low speed signal indication by moving the handle 107,

but makes an application of the brakes by operat application of the brakes, but the engineer mustacknowledge the signal indication by moving the acknowledging handle 107 and if he fails to do so,

then when a low speed signal indication is re-" ceived, the passage 132 will be connected to the stop reservoir 139 and even though the low speed governor valve 14 be closed, the reservoir 139 being at atmospheric pressure, the passage'132 will be vented to the reservoir 139 and this will cause the operation of the-pilot piston 71 and thereby the operation of the application piston 67- to effect an application of the brakes in the manner hereinbefore described except in this case, due to the medium speed valve 13 being closed, the split reduction cut-out piston 83 will be in its inner position, so that the reduction in brake pipe pressure will be effected in two stages.

When in the split reduction position, the slide valve 85 cuts off communication from passage 143 to passage 144 and thus between the reduction reservoirs 54 and 55, so that upon movement oi the application slide valve 69 to application posi-- tion, the equalizing reservoir 90 is equalized only into the reduction reservoir 54 byway of passsage 89, cavity in slide valve 69 and passage 144.

The reduction in equalizing reservoir pressure thus efiected operates the equalizing discharge Y aided by the spring 187.

to. exhaust passage 153.

piston 87 to open the discharge valve 91, sothat fluid is vented from the brake pipe 108 to passage 152;. Thence the vented-fluid flows to. chamber 76 and operates the valve piston 75 to open the restricted vent port 157 and to close the valve 77. Fluid is also-vented through passage 154, past the check valve 155, to the timing reservoir No.1, to the restricted vent port 156 and also to the chamber 94 of the diaphragm 93.

Fluid pressure equalizing into the reduction reservoir 54 also fiowsfrom passage 144 to the under sideof the reduction holdgback valve 79 and also to the outer seated area of said valve piston, while the inner seated area of said valve piston is open to the reduction reservoir, 55, which is now at atmospheric pressure, ,by way of passage 143. The valve piston-.79 will therefore be maintained in its-upper position by the higher fluid pressure acting below said piston,

Whenthe discharge valve 91 closes, due to the brake pipe-pressure being reduced to equalthe reduced pressure in the equalizing reservoir, as effected :by the reduction reservoir 54, the venting of brake pipe pressure ceases, and the timing valve piston 75 willqreturn to its upper position. The checkvalve 77wil1 then unseat, permitting the venting of fluid from the under side of piston 79 through passage 188, past the open valve 77 The pressure in reduction reservoir 54, acting on the outerexposed upperseated area of valve piston -'i '9 then operates to shift the valve piston downwardly to its lower seat. The downward movement of the valve piston unseats the valve 81, so that the chamber within the lower seat of the valve piston is vented to. the atmosphere to maintainthe valve piston in its lower seated position. The downward movement of the valve piston 79 opens communication from the reduction reservoir 54 through passage 144 to the reduction reservoir-.55 through passage 143, so that a further reduction inpressure in the equalizing reservoir is effected. This further reduction in equalizing reservoir pressure; operates tomove -the equalizing dischargepiston 87 to openthe discharge valve 91, so that thebrake pipe pressure is further reduced. Thecombined volumes of the reduction. reservoirs 54' and is such that-a fullservice reduction in brake pipe pressure is effected,

The No. .1 timing reservoir and the reduction safetyvalve will function only in case the pres:

sure at the under side of the valve piston '79 has,

not beendischarged after a predetermined period of time.

, Due to possible leakage after the discharge valve 91 seats after the first reduction in brake pipepressure has been made, the piston '75-may not move up so as, to open the .valve 77, with the resultthat the valve piston 79 will not be operatedand. the safety valve then functions to vent timing reservoir No. 1 and it will now be evident that when the discharge valve 91 closesw'after, the first reduction, if the piston '75 fails to lift,

due to leakage past the discharge valve 91, then after the time required for the timing reservoir No, 1 to leak down by way of the restricted exhaust port 156, the diaphragm 93 willm o ve1downwardly, permitting the valve 96 toopen, so as to vent fluid fromthe under face of piston '19. Said piston will then be operated to open communication betweenthe reduction reservoirs 54 and 55,

tocause a full service reduction in brake pipe pressure as would have been the case had the valve 7'7 been opened by the operation of the reduction timing valve piston 75.

It will be understood that since the split reduction cut-out valve device is moved to its cutin position when the medium speed governor valve is closed due to the speed of the train being less than the medium speed limit, the reduction of brake pipe pressure in two stages, as above described, will be effective whenever the brakes are automatically applied at any speed less than the medium speed limit.

Inorder to release, the brake valve handle must be first moved to lap position, as in releasing after passing a medium speed indication, but in this case, it will benoted that in addition to requiring the recharge of the application pipe 132, the stop reservoir 139 must also be recharged, before the pilot piston 71 will be moved back to release position, As a result, it requires a longer period of time to effect the release after passing a low speed signal'indication, if the indication is not acknowledged, and since a full service application of the brakes was made at a relatively low speed, the train will be brought to a stop before the brakescan be released. This operates as a penalty for failure of the engineer to acknowledge a low speed signal indication,

Furthermore, should the train be running at less than the low speed limitupon passing a low speed signal indication, the brakes will be applied,- if the engineer fails to acknowledge the indication, so that if the engineer should happen to be incapacitated when a low speed. indication is received, the train will be brought to a stop even if the speed is less than the low speed limit.

If the engineer acknowledges the low speed signalindication by movingthe handle 107 to acknowledging position, and the speed of the train is under the low speed limit, the stop reservoir. 139 will be charged with fluid under pressure as hereinbefore described in the first portion of the description of operation when thetrain receives a low speed signal indication. i With the stop reservoir charged with fluid under pressure, when the parts move to low speed position, in which the medium speed slide valve 24-connects the stop reservoir 139 with the application pipe 132 the low speed governor valve 14 being closed, since the train is running at less than the low speed limit, the pressure in the ap-; plication pipe 132 will be maintained by the pressure in the stop reservoir, so that the application portion of the train control apparatus will not be operated to effect an application of the brakes.

1 If the speed of the train when a low speed signal indication is received exceeds the low speed limit, the engineer should make an application of the brakes as well as acknowledge the signal'indication and sufiicient to reduce the speed of the train to less than the low speed limit before the time period expires which is provided by operation ofthe medium to low speed timing valve device. This will prevent operation. of the train, control :apparatus to effect an application of the brakes andthe brakes can thereafter be promptly released-by operating the brake valve device in the usual manner. The train may then proceed ata; speed .less than the low speed limit. a

The object of providing the restricted port 175 for charging the application pipe 132 is to prevent operation of the application pilot piston after the engineer has made an application of the brakes. -When the engineer applies the brakes, the suppression valve 64 is seated, cutting off communication through pipe 132, andafter the governor valve closes due to the speed of the train having been reduced below the indicated speed limit, that portion of the pipe and passage 132 between the governor valve and the valve 64 would be at atmospheric pressure, if the feed passage 175 were not employed, so-that when the engineer released the brakes, causing the valve 64 to unseat, the pressure in pilot piston chamber '72 would be vented to that portion of the application pipe 132 between the valve 64 and the governor controlled valve, and this would operate to cause an application of the brakes by operation of the application portion of the train control apparatus. By feeding fluid under pressure into the pipe 132 through restricted passage 175, the above undesired action is prevented, since the application pipe will be maintained charged after the governor valve closes.

By employing an additional rotary valve in the brake valve device, the existing standard brake valve device with the usual rotary valve may be retained and the additional features employed in connection with the automatic train control are provided by adding a section to the existing brake valve which includes an additional rotary valve for controlling the functioning of the train control apparatus.

By employing a pilot valve device for control ling the operation of the application valve device, the application valve device may be controlled by full main reservoir pressure and also provides for the supply of fluid at main reservoir pressure to the brake valve device, while the other parts of the train control apparatus are subject to fluid at feed valve pressure or a pressure less than the main reservoir pressure. In other words, the pilot valve device provides means for separating the application valve device from the other parts of the train control apparatus with respect to fluid pressure.

The reason it is desired to employ fluid pressure in the train control apparatus which has been reduced from the main reservoir pressure is that at the reducedpressure, moisture will not precipitate or condense out of the fluid so readily and this will prevent possible clogging of the passages with moisture.

Having now described our'invention what we claim as new and desire to secure by Letters Patent, is:-

1. In an automatic train control equipment, the combination with automatic apparatus operable to effect an application of the brakes, of a brake pipe, manually operable means for reducing the brake pipe pressure to effect an application of the brakes, and valve means operated by fluid vented from the brake pipe by operation of said venting the operation of said automatic apparaiw tus, and an additional valve means, subject to brake pipe pressure for venting fluid from said chamber and operated upon a predetermined reduction in brake pipe pressure for closing communication through which fluid is vented irom said chamber.

3. In an automatic train control equipment, the combination with. automatic apparatus operable to effect an application of the brakes,'of a brake pipe, manually operable means for reducing the brake pipe pressure to eifect an application of the brakes, valve means subject to the fluid pressure in a chamber and operated by fluid vented from the brake pipe to said chamber by operation of said manually operable means for preventing the operation of said automatic apparatus, and an additional valve means subject to brake pipe pressure, and controlling communication from said chamber to a restricted exhaust port and operated upon a predetermined reduction in brake pipe pressure for closing said communication. I

4. In an automatic train control equipment, the combination with a 'valve'mechanism operate ed upon a reduction in fluid pressure for effecting an automatic application of the brakes, of a brake pipe, a valve for controlling communication through which the fluid pressure on said valve mechanism is reduced, a movable abutment, sub ject to the pressure in a chamber, for operating said valve, a valvefor controlling communication from said chamber to an exhaust port, and a movable abutment subject to brake pipe pressure for operating said valve.

5. In an' automatic train control apparatus, the combination with a brake pipe and a valve mechanism operated upon a'reduction in fluid pressure for effecting a reduction in brake pipe pressure, of a valve for controlling communication through which the fluid pressure on said valve mechanism is reduced, a movableabutment, subject to the pressure in a chamber and operated by fluid vented from the brake pipe for closing said valve, an additional valve for controlling communication from said chamberto an exhaust port, and a movable abutment, subject to brake pipe pressure and operated upon a predetermined reduction in brake pipe pressure for closing said additional valve.

- 6. In an automatic train control apparatus, the combination with a brake pipe' and a valve mechanism operated upon a reduction in fluid pressure for effecting a reduction in brake pipe pressure, of a valve for controlling communication through which the fluid pressure on said valve mechanism is reduced, a movable abutment, subject to the pressure in a chamber and operated by fluid vented from the brake pipe for closing said valve, an additional valve for controlling communication from said chamber to an exhaust port, a movable abutment, subject to brake pipe pressure and operated upon a predetermined reduction'in brake pipe pressure for closing said valve, and manually operable means for effecting a reduction in brake pipe pressure.

'7. In an automatic train control apparatus, the combination with a brake pipe and a valve mechanism operated upon a reduction in fluid pressure for effecting a reduction in brake pipe pressure, of manually operable'means for eflecting a reduction in brake pipe pressure and means for controlling communication through which the fluid pressure on said valve mechanism is reduced and operatedupon failure of said manually operable means to effect a predetermined reduction in brake pipe pressure within a predetermined period of time for opening saidcommunication.

8. In an automatic train control apparatus, the combination with automatically operable means for efiecting an application of the brakes, a brake pipe, manually operable means for effecting a reduction inibrake pipe pressure to cause, an application of the brakes, and means operative while the brake pipe pressure is reducing and for a limited period of time after the reduction in brake pipe pressure ceases to prevent the operation of said automatically operable means to effect an application of the brakes;

9. In an automatic train control apparatus, the combination with a brake pipe, a reduction in pressure in'which is adapted to effect an application of the brakes, automatic means for effecting a reduction in brake pipe pressure, and manually operable means forceifecting areduction in brake pipe pressure, of means operating to prevent the automatic means from'effecting a reduction in brake pipe pressure for a limited period of time after a reduction in brake pipe pressure is effected by said manually operable means.

10. In an: automatic train control apparatus, the combination with a brake pipe, a reduction in pressure in which is adapted to effect. an application 'of'the brakes, automatic means ,for effecting a reduction inbrake pipe pressure, and manually operable means for efiecting a reduction in brake pipe pressure, of means operating to prevent the automatic means from effecting a reduction in brake pipe pressure for a limited r period ;of time after a reduction in brake pipe pressure is eifected by said manually operable means and for further preventing the operation of said automatic means, if a second reduction in brake pipe pressure, suflicient to reduce the brake pipe pressure to a predetermined degree, is effected by the manually operable means within said period of time.

11. In an automatic train control apparatus, the combination with a brake pipe, a reduction in pressure .in which is adapted to effect an application of thebrakes, automatic means for effecting a reduction in brake pipe pressure, and

manually operable means for effecting a reduction in brake pipe pressure, of means operating to prevent the automatic means from'effecting a reduction in brake pipe pressure for a limited period of time after a reduction in brake pipe pressure is effected by said manually operable means and :for further preventing theoperation ofsaid automatic means, if a second reduction in brake pipe pressure is effected by the manually operable means within said period oftimeu 12. In an automatic train control apparatus, the combination with a brake pipe, automatic train controlled means for effecting 'a reduction in brake pipe pressure, and manually operable means for effecting a reduction in brakepipe pressure, of means for preventing the operation of said automatic means to effect a reduction in brake pipe pressure if a predetermined reduction in brake pipe pressure is effected by said manually operable means, and means for maintaining said preventing means in the position for preventing operation of the automatic means for a limited period of time, if less than said predetermined reduction in brake pipe pressure is effected.

13. In an automatic train control apparatus, the combination with a brake pipe, automatic ,train controlled means for eiiecting a reduction in brake pipe pressure; and manually operable means for effecting a reduction in brake pipe pressure, of a valve eflective to prevent operation of said automatic means, means operative when the brake pipe pressure 'is reduced by operation of saidmanually operable means for operating said valve, and means operative to maintain said valve in its position for preventing operation of the automatic means for a predetermined time after the reduction in brake pipe pressure ceases. g

14in an automatictrain control, apparatus, the combination. with a brake pipe, an equalizing reservoir, a valve device subject to the opposing pressures oi the brake pipe and the equalizing reservoir and operated upon a reduction in pressure in the reservoir for venting fluid from the brake pipe, of manually operated means for venting fluid from the equalizing reservoir, automatic means for venting fluid from said reservoir, and a valve mechanism operated by fluid vented from the brake pipe by operation of said valve device for preventing the operation of said automatic means. i

1 5. In an automatic train control apparatus, the combination with a main reservoir and a brake application valve device subject to fluid at main reservoir pressure, of a pilot valve device subject to fluid at a reduced pressure less than main reservoir pressure for controlling the operation ofsaid application valve device.

16. In an automatic train control apparatus, the combination with a reservoir and a brake application valve device comprising a valve and a piston subiect on opposite sides to fluid at mainreservoir pressure, of a pilot valve device comprising a piston subject on opposite sides to fluid 'at a pressure, less than main reservoir pressure and :a valve operated by said piston upon a reduction .in pressure thereon for venting fluid from one side of said application piston.

17.111 an automatic train control apparatus, the combination with a main reservoir and a brakeapplilcation valve device comprising a valve and a piston subject on one side to fluid at main reservoir pressure, of a pilot valve device comprising a piston subject on opposite sides to fluid at a pressure less than main reservoir pressure and .a valve operated by said piston and having one position for supplying fluid at main reservoir pressure to the opposite side or said application piston and another position in which fluid is vented tram said opposite side.

18. In an automatic train control apparatus, the combination with abra'ke pipe, of means for automatically eirec'ting a reduction in brake pipe pressure in two stages and including a first reduction reservoir into whichfluid is vented by operation or said means to eflect the first reduction in brake pipe pressure and a second reduction reservoir into which fluid is vented to effect the second reduction in brake pipe pressure and a valve device controlled maccordance with the speed of the train for connecting the first reduction reservoir-to the second reduction reservoir to thereby render said means ineffective to cause a reduction'in brake pipe pressure in two stages.

19. In an automatic train control apparatus,-

the combination with a brake pipe, an equalizing reservoir, and a valve device subject to the opposing pressures of the brake pipe and the equalizing reservoir for venting fluid from the brake pipe, of two, reduction reservoirs, valve means for first venting fluid from the equalizing reservoir to one reduction reservoir and then to the other reduction reservoir, and a valve device controlled in accordance withth'e'speed of the train and having a position for connecting one'reduction reservoir to the other reduction reservoir.

20. The combination with a brake valve device having a rotary valve and an operating handle therefor for controlling the brakes, of an automatic train control apparatus and an additional valve controlled by said' operating handle and operative to influence the functioning of the train control apparatus. 1

21. The combination with abrake valve device having a rotary valve and an operating handle therefor for controlling the 'brakes,-'of an automatic train control apparatus and an additional rotary valve operable'by said handle for controlling the train control apparatus to the extent that the same is manually controlled.

22. In an automatic train control apparatus,

the combination with mechanism for automat-- ically ei'lecting an application of the brakes, of a brake valve device comprising'a rotary valve for controlling the brakes, a handle for-operating said valve, and an additional valve operable by said handle and controlling means for effecting the movement of said mechanism to release the brakes.

23. In an' automatic train the combination with mechanism for automatically effecting an application of the brakes, of

a brake valve device comprising a rotary valve for controlling the brakes, a handle for operating said valve, an additional rotaryva'lve operable by said handle, and means controlled'by said additional rotary'valve for controlling the release of the brakes when applied by operation.

tion of said valve means, and a safety valve de-- vice operating upon failure of the first'valve device to'act for effecting the operation of said valve mechanism for making a first and then a second reduction in brake pipe pressure compris-- ing valve means for initiating the second reduction in brake pipe pressure,'a valve device operating upon completion of the first reduction in brake pipe pressure for-effecting theoperation of said valve means,na safety. valve device operating upon failure of the first valve device to act for effecting the operation of saidvalve means, and means for delaying the operation ;of said safety valve device fora period of time after the first reduction in brake pipe pressure is completed.

26. The combination-with a brakepipe-and an equalizing discharge valve device for venting fluid from the brake pipe, of means for automatically effectingsucce'ssive reductions in brake pipe pressure byoperation ofsaid discharge valve device including valve means for initiating the second reduction in'brake pipe pressure, a valve devalve device for effecting the operation of said valve means upon completion of the first reducl tion in brake pipepressure, and asafety valve device subject to the pressure of fluid vented from J control apparatus,

the brake pipe in making the first reduction in brake pipe pressure and operating in case the first valve device fails to act to efiect the opera-v tion of said valve means.

27. The combination with a brake pipe, equalizing reservoir, and anequalizing' discharge valve device subject to the opposing pressures of the brake pipe and the equalizing reservoir, of areduction reservoir, valvemeans for connecting said reduction reservoir to said equalizing reservoir, a valve for controlling said valve means, a 'm ovable abutment subject to the pressure of fluid vented from the brakepipe byoperation of said discharge valve mechanism for operating said valve, a second valve for controlling said valve means, and a movable abutmentsubject to the pressure of fluid vented from the brake pipefor operating said second valve.. a 28. The combination'with a brake pipe, equalizing reservoir, and an'equalizing discharge valve device subject to the opposing pressures of the brake pipe and the equalizing reservoir, of a reduction reservoir, valve means for connecting said reduction reservoir to said equalizing reservoir, a valve for controlling said valve means, a movable abutment subject to the pressure of fluid vented from the brake pipe by operation of said discharge valve mechanism for operating said valve, a second valve for controlling said valve means, a reservoir adapted to be charged with fluid vented from the brake pipe, and a movable abutment subject to the pressure in said reservoir .for operating said second valve.

29. The combination with a brake pipe, equalizing reservoir, and an equalizing discharge valve device subject to the opposing pressures of the brake pipe and the equalizing reservoir, of a reduction reservoir, valve means for connecting said reduction reservoir to said equalizing reservoir, a valve for controlling said valve means, a movable abutment subject to the pressure of fluid vented from the brake pipe by operation of said discharge valve mechanism for operating said valve, a second valve for controlling said valve means, a reservoir adaptedto be charged with fluid vented from the brake pipe, a movable abutment subject to the pressure in said reservoir for operating said second valve, and a check valve for preventing back flow from said reservoir.

30. The combination with a brake pipe, equalizing reservoir, and an equalizing discharge valve device subject to the opposing pressures of the brake pipe and the equalizing reservoir, of a reduction reservoir, valve means for connecting said reduction reservoir to said equalizing reservoir, a valve for controlling said valve means, a movable abutment subject to the pressure of fluid vented from the brake pipe by operation of said discharge valve mechanism for operating said valve, a second valve for controlling said valve means, a reservoir adapted to be charged with. fluid vented from the brake pipe and having a.

restricted blow down port, and a movable abutment subject to the pressure in said reservoir,

for operating said second valve.

31. In an automatic train control apparatus. the combination with an application pipe, a reduction in pressure in which is adapted to effect an application of the brakes, a slow acting valve device for venting fluid from said application pipe, a speed controlled blow down valve, a valve for connecting said slow acting valve device with said blow down valve, a piston for operating said valve, and a magnet controlled valve for controlling the operation of said piston.

32. In an automatic traincon'trol apparatus, the combination with an application pipe, a reduction in pressu-re-in which is adapted-to effect an application of the brakes, a slow acting valve device for venting fluidfrom sai'dapplication pipe, a speed controlled blowdow'n valve, a speed governor controlled valve,avalve for connecting the applicationpipe to said speed governor controlledvalve, a pistonxfor operating said valve, a second slow acting valve device for controlling the operation of said piston,fav magnet controlled valve, a valve .for connecting the first slow acting valve-device with-said blow downspeed governor controlled 'valvegagvalve for connecting theapplic'ationpipe to saidsspeed gov; ernor controlled valve, 'a-p istonior operating said valve, a second slow acting valve device for. controlling the operation ofsaid' piston', a magnetv controlled valve, a valve for connecting the first slow acting valve devicewith said-blow down valve and the second slow acting valve devicewith said magnetcontrolled valve, a piston for operating said connecting valve, and a magnetcontrolled valve for controlling. the operation of said piston; '34. In an automatic train control apparatus,-

the combination with a pipe and means operated upon a reduction in pressure insaid pipe for ef-- fecting an application of the brakes, of a stop reservoir, meansoperated upon a change in the signal indication ior connecting said stop reservoir to said pipe, and meansund'er the control of the engineer through which said reservoir is connected to said pipe.

35. In an automatic thec'ombination with a pipe and means operated upon a reduction in pressure in said pipeior cf-1 fecting an application of the brakes, of a stop reservoir, means for connecting said reservoir to the atmosphere and operated upon a change in the signal indication for connecting said stop reservoir to said pipe, and means under the control of the engineer for controlling communication through which said reservoir is connected to said pipe.

36. In an automatic train control apparatus, the combination with a pipe and means operated upon a reduction in pressure in said pipe for effecting an application of the brakes, of a stop reservoir, means for connecting said reservoir to the atmosphere and operated upon a change in the signal indication for connecting said stop reservoir to said pipe, and means operable by the engineer for closing communication through which said reservoir is connected to said pipe.

37. In an automatic train control apparatus, the combination with a pipe and means operated upon a reduction in pressure in said pipe for effecting an application of the brakes, of a stop reservoir, means for connecting said reservoir to the atmosphere and operated upon a change, in the signal indication for connecting said reservoir to said pipe to thereby effect a reduction in pressure in said pipe and a consequent application of the brakes, and means operable by the engineer for closing communication through which for controlling communicationtrain control apparatus,v

said reservoir is connected to said. pipe to prevent an-applicationof the brakes. 38. Inran automatic train control apparatus, the: combination with a pipe and means operated upon a reduction in pressure in said pipe for effectingan application'of the brakes, of a stop reservoir, means for connecting said reservoir to.

the atmosphere and operated upon a change in the signal indication for connecting saidreser-.

voir to said pipe to thereby effect a reduction in pressure in said pipe and a consequent application ofthe brakes, and. means operable by the engineer for closing. communication through w'hichsaid reservoir is connected to said pipe and for opening/"communication for supplying fluid under pressure to said'reservoir.

39. Irlxan automatic train controlapparatus, theiccmbinationiwith a pipe and means operated upon a reduction in pressure insaid. pipe for ef-.

fecting an application of the brakes, of a stop reservoir, means for connecting said reservoir to.

th'e atmo 'sphere a'ndoperated upon a change in the signal indication for connecting said reservoir to said pipe, to thereby effect a reduction in pressure in said pipe, a ,valve device for controlling communication through which saidreservoir is connected to said pipe, and manually operated.

means for operating 'saidvalvedevice to. close said communication.

1 40. In. an automatic trainoontrol apparatus,

. the combination with a pipe and means operated upon a reduction in pressure in said pipe for effecting an application of the brakes, of a stop reservoir, means for connecting said reservoir" to the atmosphereand operated upon a change in the signal indication for connecting said, reservoir to said .pipe, to therebycffect a reduction in pressure in said pipeQa valve devicejoperated by anincrease in fluid pressure for closing communication throughwhich said reservoir is connected to'said'pipe, and manually operated meansifor supplying fluid to said valve device.

41. In an automatic train control. apparatus, the combination with a pipe and means operated upon-"a reduction in pressure in said pipe for effecting an application of the brakes, of a stop reservoir, means forconnecting said reservoir to the atmosphere and operated upon a change in the signal indication'for connecting said reservoir to said pipe, to thereby effect to reduction in pressure inpsaidpipe, a valve device operated by an increase in fluid pressure for closing communication through which said reservoir is connected to said pipe, a normally charged reservoir, a manually operated valve for connecting said reservoir to said valve device, and a restricted blow down port for gradually venting the fluid pressure from said valve device.

42. In an automatic train control equipment, the combination with a brake pipe, of means operated upon a change in the signal indication for effecting an application of the brakes, manually controlled means for eiiecting a reduction in brake pipe pressure, and means for suppressing the operation of said signal indication controlled 'means so long as the brake pipe pressure is being reduced.

43. In an automatic train control equipment,

the combination with a brake pipe, of means opthereby in brake pipe pressure for maintaining said suppressing means in its suppressing position.

44. In an automatic train control equipment, the combination with a brake pipe, of means operated upon a change in the signal indication for effecting an application of the brakes, manually controlled means for effecting, a reduction in brake pipe pressure, means operated by fluid vented from the brake pipe. for suppressing the operation of said signal indication controlled means, and means operated upona predetermined reduction in brake pipe pressure formaintainingsaid suppressing means in its suppressing position.

45. In an automatic train control equipment, the combination with a brake pipe, of means operated upon a change in the signal indication for effectingan application of the brakes, manually controlled means for efiecting a reduction in brake pipe pressure, means operated by fluid vented from the brake pipe for suppressingthe operation of said signal indication controlled means, and means operated upon-a predetermined reduction in brake pipe pressure for supplying fluid from the brake pipe to said suppressing means to maintain said suppressing means in its suppressing position.

46. In an automatic .train control apparatus, the combination with a brake pipe, of means for automatically efiectinga reduction in brake pipe pressure in. two stages, mechanism for cutting said means into and out of operation, and means for effecting the movement of said mechanism to its cut-in position when the speedof the train is less than a predetermined degree.

4'7. In an automatic train control apparatus the combination witha brake pipe, of means for automatically effecting a continuous reduction in brakepipe pressure-when the speed of the train exceeds a predetermined speed limit and for automatically effecting a two stage reduction in brake pipe pressure when the speed'of the train is less than said predetermined speed limit.

' 48. In anautomatic train control apparatus, the combination with a brake pipe, of means for automatically efiecting a continuous reduction in brake pipe pressure or .a gradualreduction in brake pipe pressure, and'means governed by the speed of the train forcausing one or the other of said reductions to be effected.

49. In an automatic train control apparatus, the

causing one or the otherv of combination with a brake pipe, of means for automatically efiecting a continuous reduction in brake pipe pressure or a gradual reductionin brake pipe pressure, means for causing, one or the other-of saidreductions'to be effected, and means controlled by the speed of the train for selectively effecting one or the other of said reductions.

50. In an automatic train control apparatus, the combination, with a brakepipe, of means for automatically effecting a continuous reduction in brake pipe pressure or a gradual reduction in brake pipe pressure, a speed, controlled governor, and a valvedevice operated by said governor for said .reductions to be effected.

51. In an automatic train control equipment,

the combination with automatic apparatus oper.

able to effectv an applicationof the brakes, of a brake pipe, rnanually operableymeans for-reducing the brake pipe, pressure to eflectan application of the brakes, and. valve means operated by fluid ventedfrom the brake pipe by operation 0! said manually operable means for preventing the operationof said automatic apparatus, communi-- brake pipe, manually operable means for reduc-'- ing the brake pipepressure to effect an application of the brakes, and valve means operated by fluid vented from the, brake pipe by operation of said manually operable'means; for preventing the operation of said automatic apparatus, communication through which fluid vented from the brake pipe is supplied to said valve means being closed when the automatic apparatus operates .to effect anapplication of the brakes. i

53. In an-automatic train control, apparatus, the combination with a brake pipe, of means for automatically effecting a reductionin brake pipe pressure in two stages, a speed governor operated at a speed proportional to the speed of the train, and means operated by said speed governor when the speed of the train'exceeds a predetermined speed limit for preventing the brake pipe pressure from being reduced in two stages.

CLYDE C. FARMER. THOMAS H. THOMAS.

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