US1173673A

US1173673A - Electropneumatic air-brake system.

Info

Publication number: US1173673A
Application number: US78225213A
Authority: US
Inventors: George Macloskie
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1913-07-31
Filing date: 1913-07-31
Publication date: 1916-02-29
Anticipated expiration: 1933-02-28
Also published as: GB191322224A

Description

G. MACLOSKIE.

ELECTROPNEUMATIC MR BRAKE SYSTEM.

APPLICATEON FILED JULYSI. 1913.

wsmsw Patented. Fab :29. mm.

' Witmesses 1 'lnventsr-z Geo! e macimsim e,

His fittwwne g.

GEGRGE MACLOSKIE, F SCHENECTADY, NEW YORK, ASSIGNOR 'lO GENERAL ELECTREC COMPANY, A CORPORATION 015 NEVJ' YORK.

ELECTROPNEUMATIC AIR-BRAKE SYSTEM.

Application filed July 31, 1913.

To all whom it may concern:

Be it known that 1, Greece MAcLosnin, a citizen of the United States, residing at Schenectady; county of Schenectady, State of New York, have invented certain newand uset'ul Improvements in Electropneumatic Air-Brake Systems, of which the following is a specification.

My invention relates to electro-pneumatic air brake equipments and the objects of my improvements are particularly to secure greater certainty and rapidity of operation of the brakes and to guard against possible accidents which may happen to various parts of the system. I

My invention will be better understood from the detailed description following and its scope will be particularly pointed out in theappended claims. The single figure of the drawings illustrates diagrammatically an electro-pneumatic air brake system involving my invention.

This system includes a control or reservoir pipe 1 supplied by a main reservoir 9., preferably through a reducing valve 8, a

pump 4 being used to maintain the pressure in the main reservoir as has heretofore been common. The reservoir pipe 1 supplies air to the motormans valve 5 and also directly to the brake cylinders through a distributing valve as will be later described. The controller 6 of the electric side of the system is attached to the motormans valve and operates therewith. As is common, particularly on electric locomotives and cars, two

valves and controllersare used, one at each end of the locomotive or car. At the left hand side of the drawing 1 have shown the motormans valve and the controller developed in a plane surface and at the right hand side I have shown them in elevation.

To the usual controller and valve 1 have added a selector switch 7 and a selector valve 8; these are also shown developed at the left hand side of the drawing and are included in the valve casing and controller box 5 and 6 at the right hand side of the drawing.

Their construction and mode of operation Specification of Letters Patent.

Serial No. 782,252.

type wherein the train pipe is exhausted to atmosphere when its piston is moved to emergency position for I desire to take advantage of this exhaust in a novel man ner as will be later pointed out.

The motormans valve 5 has six operating positions and, readingi'rom right to left they are, respectively, release, retain, lap, first service, second service and emergency. In the. release position the control pipe 1 is connected to the train pipe 9 through a large port in the motormans valve; air is then supplied from the control pipe 1 to the train pipe 9 and from thence through the triple valve 10 in the ordinary way to the supplemental reservoir 11 and auxiliary reservoir 12. In the retain position the connection of the control pipe 1 to train pipe 9 is through a diminished port. In the lap position the port of control pipe 1 is blanked. In all three of these positions the exhaust ports 13 and 1a of the motormans valve are blanked. In the first and second servicepositions the train pipe 9 is con nected to the exhaust port'13 through a diminished passage and a full passage respectively. In the first service position, as will be understood, the brakes are more slowly applied than in the second service position, since the air can escape but slowly through the exhaust port 13. In the emergency position, the train pipe 9 is connected direct through full passages to the

exhaust ports

13 and 14. The operation of the pneumatic system above outlined, is the operation of the ordinary automatic air brake systems, the supplemental reservoir 11 being used to obtain the variable release feature. To the pneumatic system is added an electric system operating the brakes pneumatically through the control of a distributing valve 15. In the enlarged portion 16 of the main chamber of this valve, is located the piston 17 controlling the slide valve 18. This main chamber has an exhaust port 19. A pipe 20 connects the exhaust port of the triple valve with the main chamber of the distributing valve 15 and when the .piston 17 of the distributing valve 15 is in the left hand position, as indicated, the exhaust port of the triple valve is connected through. the slide valve 18 to the exhaust port 19, and under this conditionthe pneumatic side of the system may operate as though, the dis tributing valve 15 Wereabsent. The control Fat-cared Feb. 29, 191%. p

nioved to its extreme right hand position.

Through the brake cylinder port 25 the main chamber of the distributing valve l5 connected to the brake cylinder-pipe 26 from the triple valve, and hence to the brake cylinder 27. It will be apparent from this construrtion that when the distributing valve piston 17 is moved to the right, it will unseat the poppet valve 23 and close the exhaust port 19; air will then flow from the control pipe 1 through the pipe 22- and the chamber 21 to the main chamber of the distributing valve, and from thence to the brake cylinder, being prevented by the slide valve 18 from escaping through the pipe 26 and the triple valve exhaust port. To revcnt air from escaping about the piston 17, the packing 41 is added.

Tl i application magnet valve 31 and the release magnet valve 33 control the pres sure on the rear of .the piston 17 and hence its operation. The application mag-net valve 31 is a simple puppet valve between two chambers nori'nally held to its seat by a spring and the pressure behind it. The release magnet valve 33 comprises three cham bers 2H, 37) and 30. The chamber 3t has an exhaust port 37 to atmosphere. The chamber 35 is connected to an application reservoir 29 and the rear of the chamber 16 of the. distributing valve 15.b v the pipe 38. The chamber 36 is connected to the application magnet valve 3 A puppet valve 32 is located between the chambers 35 and 3i3 and a puppet valve 39 is located between the chambers 3t and these valves bein conthrough thepipe 38, chamber 35, chamber 3% and the, exhaust port 37. Y

The air for operating the piston 17 through the application magnet valve 31 is taken from'thc auxiliary reservoir 12. Instead of using air from the auxiliary reservoir direct, however, I prefer to take it from what I term a pressure reservoir 28, which is supplied, from the auxiliary reservoir through the charging magnet valve 30 con ing of a puppet valve between two chambers, one being connected to the auxiliary reservoir and the other to the pressure reservoir, the puppet valve normally being held off its seat by a spring.

To operate the charging valve 30, the application valve 31 and the release valve 33, I have provided the solenoids and cores 43, 4A and for these valves, respectively, and a set of train wires. One end of each of the solenoids is connected to ground. The train Wires are five in number: an emergency wire 426, the function of which will be later described, a release wire 47, th'e'trolley wire 48, the application wire 49, and the circuit wire 50. The emergency wire 46, the application wire 49 and the trolley wire -18 are connected to the controller 6 by the wires 63, (34 and respectively. The circuit wire 50 provides for the pneumatic operation of the system in case of the breakage of one of the train wires which might otherwise prevent the operation of the electrical side of the system and an application of the brakes at all. This'feature will be later described in detail. The solenoid 43 of the charging of the train connectors 51 and 52 connect.

the application wire 49 and the circuit wire 50. Between. the trolley wlre l8 and the release wire 4:7 is a contactor 53,'adaptedto be actuated by the solenoid 54 connected from the clrcult wire- 50 to ground; thus when the circuit w1re 50 is energ zed ad aCent its connection to the solenoid 54, the contactor 53 connects the trolley wire 48 to the release wire 47 and the release wire 47 is thereby energized.

The selector switch 7 has two positions, the pneumatic and the electric. In the pneumatic position of this switch it connects together the two leads 55 and 56 from the circuit. wire 50, thereby making the circuit wire continuous through this end. of the car and systemand otherwise rendering this portion of the" electrical side of the system inoperative so far as the control of the system is concerned. In the electric position of the selector switch 7, the leads 57 and 58, one of which is attached to the trolley and the other to the trolley wire 48-are connected together and the adjacent controller is adapted to control the elec trical system. Only through the wire 58 and the selector switch. in electrical position, can energy be supplied to the electrical side of the system. The selector-switch 7 in the electric position, also connects together the wire 60 from the controller 6,

the wire 61 to the release wire t? and the safety magnet valve wire 62. The safety exhaust ports 13 of the motormans valve, as has heretofore been common, and 1s adapt ed when energized, to close this port. The

selector valve 8 is connected by the pipe 67 to a supplemental exhaust port of the motormans valve 5, and is also connected by the pipe 68 to the exhaust pipe 13 and the safety magnet valve 66, as indicated. In the pneumatic position of the selector valve 8, the ports to-these two pipes are blanked. In the electrical position of this selector valve 8, however, the ports of these two pipes are connected together. The selector valve 8 and the selector. switch 7 may be connected to operate together and are designed to control the operation of the whole system to the extent of directing the operation of the brakes pneumatically or electrically, as desired. They are to be thrown to the pneumatic position when the pneumatic operation of the system is desired and to the electric position when the electrical operation ot'the brakes is desired. This will be better understood from the following description of the operation of the sys-' quick application of the brakes. This valve is controlled by the solenoid 70 connected to the emergency wire L6 and the ground. I preferably add a vent valve 71 to each triple valve for energizing the emergency wire whenever one triple valve throughout a train goes into emergency position whatever may cause it to do so. This valve is conpected to the emergency application exhaust port, that port of the triple valve thrhngh which air is exhausted from the train pipe and from the rear of the triple valve piston in an emergency application. Air coming from any one of the triple valves forces open theattached pivoted valve 72, normally held closed by its spring 73, thereby closing its switch 74. This switch. through the wire 75 connects the trolley wire 48 to the emergency wire 46, simultaneously energizing all the emergency valves 69 throughout the. train and thus almost simultaneously opening the train pipe adjacent each triple valve and resulting in an equally rapid application of the brakes on every car irrespective of the number of cars in the. train and the length of the train pipe. 9.

The electrical operationand the combined electrical and pneumatic operation of this system are follows: The selector switch and valve 7 and 8 are first moved to the electric position. The wires 57 and 58 are then connected together and energy is carried to the trolley wire t8, and the controller 6 over the

wires

58 and 65. The various mansvalve 5 to the pneumatic side of the system, charging it as will be understood.

Air is also supplied from the auxiliary reservoir to the pressure reservoir through the charging valve 30, which is open under the control of its spring. I I

To apply the brakes, the controller 6 is moved to either the first or second service position. In either position the application wire 49 is connected through the wire 6% to the trolley pole through the wire 65. The wire. 60 is disconnected from the wire and hence the release wire 4:? and the safety magnet valve 66 are no longer energized through the motormans controller. If, however, the application wire 49 and the circuit wire 50 are continuous throughout the train, energy passes from the front car to the connector 51 at the rear of the train, to the circuit wire 50 and from thence to the solenoid 54:, closing the contactor 53. Through this .contactor then, the release Wire '47 is again energized and the charging valve 30 and the release magnet valve 33 are maintained in the same positions as when the controller 6 was in the lap or retain positions. The safety magnet valve 66 also receives energy'from the release wire 47 over the wire 61, and through the selector switch 7 and over its wire Thus the exhaust port 13 of the ,motormans valve is still held closed providing the application wire and the circuit wire are continuous through the train. In addition, however. the solenoid 14 has been energized and the application magnet valve opened. Air passes from the pressure reservoir 28 to the application reservoir 29 and to the rear face of the piston 17 of the distributing valve. The piston 17 and the valve 18 are then moved to the right The exand the puppet valve 23 opened. haust port 20 of the triple valve is closed by the valve 18. Air flows from the control pipe 1 over the pipe 2' to the distributing valve 15 and from thence through the brake pipe 26 to the brake cylinder 27. The longer the application valve 31 is held open, the greater becomes "the pressure in the application reservoir 29 to the limit of the equalization of the pressure in the pressure reservoir 28 and that 1n the application res ervoir 29. The pressure in the brake cylinder in every instance increases until it becomes slightly greater than that in the application reservoir29. \Vhen. this occurs the piston 17 is moved to the left by the brake cylinder pressure on its front face and by the pressure of the spring 24, a sufiicient distance to allow the puppet valve 23 to seat. As soon as this valve is seated, the pressure of the spring 2a is removed from the piston 17 and the pressure in the cylinder 27 alone is not suflicient to continue the movement of the piston 17. The result is cause the exhaust port 19 1s still cover! 1 by the valve 18, but no more an. can pass into the brake cylinder 27 through the distributing valve unless the pressure in the application reservoir 29 becomes greater than the pressure in the brake cylinder 27 plus the pressure of the spring 24. The pressure in the brake cylinder and the application reservoir 29 are always Within a few pounds of each other. It will appear from this that in applying his brakes, the motorman moves his controller to service position for ashort period of time and then back. to lap. In

this position, as also in retain position, the. wire (30 1s connected to the trolley through the

wires

65 and 58 and through the selector switch 7 and energy supplied over the wire 62 to the satety ma gnet valve 66, which then closes the exhaust 13 of the motormans valve; energy is also supplied over the Wire (31 to the release wire 47. Energizing this wire energizes solenoids 418 and 45, closing the cl'iarging magnet valve 30, thus cutting otl' conununication between the auxiliary reservoir and the pressure reservoir 28, and seating puppet valve 89 in the release magnet valve, and unseating puppet valve 32 therein. This results in disconnecting the chamber 16 of the distributing alve and the application reservoir 29 from the atmosphere and'connecting them to the application magnet valve 31. The application wire 49 is deenergized, however, and hence the application magnet valve 31 closes the passage between the pressure reservoir 28 and the application reservoir 29. The piston of the distributing valve is therefore only affected by the pressure previously given to the application reservoir 29, and hence the pressure in the brake cylinder is main.- taiued. If this braking force is not as great as desired. the motor-man increases the pressure in the application reservoir 29 by returning the controller to the service position for another short period of time. When he desires to release his brakes, he returns the controller to the release position for a short period of time to allow the escape of a small amount of air from the application reservoir to release them partially, or for a longer period of time to release them completelv. since any amount of air that there may be in the brake cylinder may be retained by holding the controller on the retain or lap positions;

The function of theapplication reservoir is to give added capacity to the rear of the piston 17 and hence more ready control of puppet valve 3-.

the brakes, .The general action of distributing valves is well understood. When the motorman returns the controller to the re lease position, not only is the application magnet valve deenergized, as it is also in the lap and retain positions, but also the that the brakes are maintained applied be- 'valve through the action of the spring 40,

closes the puppet valve 32, further disconnecting the application reservoir from the pressure reservoir, and opens the puppet valve 39 connecting the application reservoir and the rear end of the piston 17 to the atmosphere. The pressure in the brake cylinder- 27 then returns the piston 17 to its left hand position, as indicated, and the air is released from the brake cylinder through the pipe 26, triple valve 10, the triple valve exhaust 20, and the exhaust port 19 of the distributing valve 15. The function of the pressure reservoir 28 is to limit the possible b airing power. Without this reservoir and the charging valve 30, taking air from the auxiliary reservoir direct, it would be possible to obtain control pipe pressure in the brake cylinder, but by properly proportioning the pressure reservoir and the application reservoir any limit below this maximum may be fixed. The function of the puppet valve in the release magnet valve is to prevent the loss of air in the case of certain accidents. 'For example, suppose a car equipped with the system illustrated, with the exception of the contactor 53, is a part or" the train, and further suppose that the release wire 47 isbroken ahead of this car. Neither the charging magnet valve 30 nor the release magnet valve 33 could be energized and an attempt to apply the brakes electrically would result in a loss of air, air flowing from the adjacent auxiliary reservoir through the charging gnagnet valve and the application magnet valve to atmosphere through the exhaust port oi? the release magnet valve were it not for the This valve, however, is seated when-the release nagnetvalve is deenergized and prevents this loss.

It may occur, however, that the current fails for any one of a number of reasons, and that the motorman attempts to operate his brakes electrically. In the release, retain and lap positions of the motormans valve jand controller, the operation of the pneumatic side of the system is not affected by the electrical side at all. Should, however, the current fail at the trolley, the safety magnet valve at once opens the exhaust port of the motormans valve and allows the ap: phcation of the brakes on lap position of the controller by Way of the pipes 67 and aliases 68. lhis is oi advantage because the current may fail while the controller is on lap position after the brakes have been applied with some degree of pressure. If no provision were made for continuing the application'of the brakes pneumatically, the brakes would be entirely released at a time when the motor-man should expect the train to be stopping. By using the selector valve and the supplemental exhaust pipe 67, however, the motorman may feel sure that he has full command of his brakes at all times and that at the worst the brakes will be applied pneumatically one step earlier than he would naturally expect them to be. There is another'danger in various forms of electric pneumatic systems. It is possible that the train wires may break behind the first or head car, or perhaps not be coupled together,

leaving the system in such a condition that an application electrically results in eX- hausting the air from the automatic system, perhaps without applying the brake To prevent this actio .1 have provided the circuit Wire 50. This wire controls what- I have called the release magnet valve 33 including the puppet valve 32. In order that air may be taken from the pressure reservoir or the pneumatic side of. the system, it is necessary that the release wire 47 be energized; but the energization of this wire is controlled by the solenoid 54, connected to the circuit wire 50, and the circuit wire 50 receives its energy only from the application wire 4:9 at the rear end of the train. Hence should the train wires be ruptured at any point throughout the train, the circuit wire is denergized, the puppet valve 32 closed, the satety magnet valve 66 opened and the system operates as an ordinary pneumatic system with the exception as ber'ore pointed out, that application may now be secured in the lap position in addition to the regular service positions.

.l/Vhen the motormans valve and controller 5 and 6 are moved to emergency position, the brakes are applied through the energization of the emergency Wire The solenoid 70 of the emergency magnet valve 69 is energized and the train pipe 9 opened adjacent each triple valve 10, allowing a very quick application of the brakes. When operating eithe electrically or pneumatically the vent valve 71 produces an almost simultaneous pneumatic emergency operation on the breaking of the train pipe 9. The first triple valve which goes into emergency position, exhausts air through its vent valve (1, closing the switch 74 and energizing the emergency wire 46 through the wires 75 from the trolley wire 48. This results in the' opening of each emergency magnet valve 69 adjacent its respective triple valve if the emergency wire has not already been otherwise energized.

ing a lap position, means for electrically controlling the brakes, and means for pneumaltically applying the brakes on a failure of the electrical energy supplying the electrical portion of the system when the engineersvalve is in lap position.

2. In an electro-pneumatic air brake systern, an engineers valve for pneumatically controlling the operation or the brakes, means for electrically controlling the brakes, and means for pneumatically applying the brakes on a failure of the electrical energy supplying the electrical portion of the system when the engineers valve is in another position than an application position.

3. In an electro-pneumatic air brake sy tem, an engineers valve for pneumatically controlling the operation of the brakes, a controller for electrically controlling the brakes connected to and operating with the 'engineers valve, and means allowing the pneumatic application of the brakes on the failure of the electrical energy when the engineers valve is in other than an application position.

t. In an electro-pneumatic air brake system, an engineers valve for pneumatically controlling the operation of the brakes, a controller for electrically controlling the brakes connected to and operating with the engineers valve, and means allowing the pneumatic application of the brakes on the failure of the electrical energy when the engineers valve is in lap position.

In an electrofpneumatic air brake sys tem, an enginee'rs Valve for pneumatically controlling the operation of the brakes having the usual exhaust port and, a second 81(- haust port connected to the brake pipe port in lap position. of the valve, a second valve controlled from the source of electrical supply :tor closing said second exhaust port, and a controller for electrically controlling the brakes.

6. In an electro-pneumatic air brake system, an engineers valve for pneumatically controlling the operation of the brakes having the usual exhaust port and a second exhaust port connected to the brake pipe port in a position other than an application posi tion of the valve, a second valve controlled from the source of electrical supply for closing said second exhaust port, and a controller for electrically controlling the brakes.

7. In an electro-pneumatic air brake system, an engineers valve for pneumatically controlling the operation of the brakes, a controller fo controlling the electrical operation of the brakes, a release magnet valve for retaining the brakes applied when energized through said controller, and means for pneumaticallv applying the brakes on a failure of the electrical energy energizing said release valve.

8. In an electro;pneumatic air brake systern, an engincers valve .t'or pneumatically controlling the operation of the brakes, having the usual exhaust port and a second ex haust port connected to the brake pipe port in a position other than pneumatic application position, a valve controlled from the source of electrical supply for said second exhaust port, a controller for controlling the electrical operation of the brakes, and a release magnet valve for retaining the brakes applied when energized through said controller.

9. In an electro-pneumatic air brake sys-' tem, an engineers valve for pneumatically controlling the operation of the brakes, havto and operating with the engineers valve,

and a release magnet valve for retaining the brakes applied When energized through said controller.

10. In an electro-pneumatic air brake system, an enginecrs valve for pneumatically controlling the operation of the brakes, havingthe usual exhaust port and a second exhaust port connected to the brake pipe port in a position other than a pneumatic application position, a controller for controlling the electrical operation of the brakes, a release magnet valve for retaining the brakes applied when energized through said controller, and a selector valve and switch in one position disconnecting the controller from its source of energy and closing the sec- 0nd exhaust port and in another position connecting the controller to its source of energy and opening the second exhaust port.

11. In an eleetro-pneumatic air brake system, an engmeers valve for pneumatlcally controlling the operation of the brakes, having the usual exhaust port and a second exhaust port connected to the brake pipe port in a position other thana pneumatic application position, a controller for controlling the electrical operation of the brakes, a release magnet valve for retaining the brakes applied when energized through said controller and a selector valve and switch in one position disconnecting the controller from its source of energy and closing-the tem, an engineers valve for pneumatically controlling the operation of the-brakes, having the usual exhaust port and a second exhaust port connected to the brake pipe port in a position other than a pneumatic application position, a controller for controlling the electrical operation of the brakes, a release magnet valve for retaining the brakes applied when energized through said controller and a selector valve and switch in one position disconnecting the controller from its source of energy and closing the second exhaust port and in another position connecting the controller to its source of energy and opening the second exhaust port, and an automatically opening magnet valve closed when energized controlling the usual exhaust port of the engineers valve'and connected to the same source of energy as supplies the controller by the selector valve and switch when in its second mentioned position.

13. In an electro-pneumatic air brake sys tern, an engineers valve for controlling the pneumatic operation of the brakes,va controller for controlling the electrical operation of the brakes, an automatically opening safety magnet valve connected to the same source of energy as the controller controlling the usual exhaust port of the .engineers valve, and means for exhausting the air from the brake pipe in another than an application position of the engineers valve also controlled by said safety magnet valve.

14. In an electro-pneumatic air brake system, an engineers valve for controlling the pneumatic operation of the brakes, a controller for controlling the electrical operation of the brakes, a selector valve, an automatically opening safety magnet valve connected to the same source of energy as the controller ,controlling the usual exhaust port of the engineers valve, and means for exhausting the air from the brake pipe in another than an application position of the engineers valve controlled by said safety magnet valve and said selector valve.

15. In an automatic air brake system including the usual brake pipe and automatic valve mechanism provided With an emer gency application exhaust port, a normal T closed valve means for exhausting the brake pipe including electrically operated means for opening such valve, an emergency Wire for supplying energy to said electrically operated means, and means operable by the brake pipe, and means operable by the passage of air through said automatic valve emergency exhaust port controlling said brake pipe exhausting valve means.

Y. In an automatic air brake system comprising the equipments of a plurality ,of cars, each equipment including the usual brake pipe and valve mechanism, an electrically controlled exhaust valve in each equipment for exhausting the train pipe, an emergency wire connecting the exhaust valves on a plu rality of cars, and means operable on an emergency reduction of the brake pipe controlling the euergization of the emergency Wire.

18. In an automatic air brake system COIIlprising the equipments of a plurality of cars, each equipment including the usual brake pipe and automatic valve mechanism, a normally closed exhaust valve including electricallypperated means for opening each exhaust valve for exhaustin the brake i e of each car, an emergency wire connecting the exhaust valves, and a pneumatically operated means in each equipment for energizing said emergency Wire, one of said means being connected to each automatic valve mechanism and receiving air there from as its valve goes to emergency position.

19. In an air brake system, a source of air supply, a brake cylinder, a distributing valve for controlling the supply of air from said source to the brake cylinder, a pressure reservoir, a valve controlling the supplyot' air to the pressure reservoir, a valve controlling the supply of air from such pressure reservoir to the distributing valve and controlling. means for said controlling valves through which said first mentioned control valve cuts oil the pressure reservoir from its source of supply when said second mentioned control valve allows said pressure reservoir to supply air to the distributing valve.

20. In an air brake system, a source of air supply, a brake cylinder, a distributing valve for controlling the supply of air from 1 said source to the brake cylinder, a pressure reservoir, a control valve controlling the supply of air to the pressure reservoir, a 7

control valve controlling the supply of air from such pressure reservoir to the distributing valve, and interlocking means for said controlling valvesthrough Which said first mentioned control valve cuts oil the pressure reservoir from its source of supply when said second mentioned control valve l cylinder, a pressure rcsciv allows said pressure reservoir to supply air to the distributing valve.

21. In an air brake system, a source of air supply, a brake cylinder, a distributing valve for controlling the supply of air from said source to the brake cylinder, a pressure reservoir, a. valve controlling the supply of air to the pressure reservoir, a valve controlling the supply of air from such pressure reservoir to the distributing valve, a.

valve for releasing the air supplied by the pressure reservoir to the distributing ,valve and interlocking means through which said first mentioned control valve connects the pressure reservoir to its source of supply when said release valve releases the air supplied to thedistributing valve by the pressure reservoir.

In an air brake system, a source of air supply, a brake cylinder, a distributing valve for controlling the supply of air from said source to the brake cylinder, a pressure reservoir, a, valve controlling the supply pt air to the pressure reservoir, a valve'coptrolling the supply oi air from such pres sure reservoir to the distributing valve,a valve for releasing the air supplied by the pressure reservoir to the distributing valve and interlocking means through which said first mentioned control valve and said re lease valve close when said second mentioned control valve allows said pressure reservoir to supply air to the distributing valve.

23. In an automatic air brake system including the main reservoir, automatic valve, auxiliary reservoir and garake cylinder, a distributing; valve for con, rolling the supply l air from the main reservoir to the b 'alre cylinder, a pressure reservoir of limited capacity for supplying the air for controlling the distributing: valve, a connection between said pressure reservoir and the, auxiliary reservoir, a valve in said connection, and an application valv for controlling the supply of air from the pressure reservoir to the distributing valve.

24', In an automatic air brake system including the main reservoir, automatic valve, auxiliary reservoir and brake cylinder, a distributing valve for controlling; the supply of air from the main reservoir to the brake oir of limited capacity for supplying theair for controlling the distributing, valve, a'connection between said pressure reservoir: and the auxiliary plication valv'e for con rolling the supply of reservoir, a. valve in sald connection, an ap- 25.The combination with an automatic air brake system including an automatic valve, auxiliaryreservoir and brake cylinder and the usual connections between the same, of distributing valve connected to the brake cylinder, to the automatic valve exhaust port and to a source of air and pro vided with an exhaust port andvalve means normally closing the port to the supply of air and for closing the exhaust port and further provided with a piston controlled by the pressure in the brake cylinder and another pressure controlling .said valve means, a pressure reservoir, for supplying said other pressure, a connection between the pressure reservoir and the auxiliary reservoir, a control valve in said connection, and an application valve controlling thepassage of air from the pressure reservoir to the distributing valve. piston.

26. The combination with an automatic.

air brake system including an automatic valve, auxiliary'reservoir and brake cylinder and the usual connections between the same, of a distributing valve connected to the brake cylinder, to the automatic valve exhaust port and to a source of air and provided with an exhaust port and valve means normally closing the port to the supply of air and for closing the exhaust port and further provided with a piston controlled by the pressure in the brake cylinder and another pressure controlling said valve means, a pressure reservoir for supplying said other pressure, a connection between the pressure reservoir and the auxiliary reservoir, a control valve in said connection, an application valve controlling the passage of air from the pressure reservoir to the distributing valve piston, and interlocking means through which the control valve closes the connection between the auxiliary reservoir and the pressure reservoir when the application valve permits the passage or air from the pressure reservoir to the dlstributmg valve.

27. The combination of a brake cylinder, a valve connected to the brake cylinder for supplying air thereto, a distributing valve also connected to said brake cylinder, and controlling ineans'for the air supplied to the distributing valve for controlling the operation of the same, said distributing valve having a piston subject to brake cylinder pressure on one side and the pressure of the controlling means on the other and means between said piston and said controllingmcans for preventing the leakage of air from the brake cylinder ,to said controlling means when the brake cylinder pressure exceeds the pressure of said controlling means.

28. The combination of a brake cylinder, a valve connected to the brake cylinder for supplying air thereto, a distributing valve also connected to said brake cylinder, and

controlling means for the air supplied to the distributingvalve for controlling the operation of the same, said distributing valve having a piston subject to brake cylinder pressure on one side and the pressure of the controlling means on the other and a packing -for the piston (in which it seats when the brake cylinder pressure exceeds the pressure of said controlling means.

29. The (zombination with an electro-pneumatic air brake system, of an energy wire and a, circuit wire running through the train, a connection between the two at the rear end of the train, a relay energized by said circuit wire having a pair of contacts, and a normally open safety magnet valve connected through said relay contacts to the energy wire controlling the exhaust port of the engineers valve.

30. The combination with an electro-pneumatic air brake system, of a safety magnet valve controlling the exhaust port of the engineers valve, and a wire controlling the supply of energy to said safety magnet valve running through the train and receiving its energy at the rear end thereof.

' 31. The combination in an electro-pneuopening the same to atmosphere, a safety.

magnet valve controlling the exhaust port of the engineers valve, and a single means controlling the supply of energy to the safety magnet valve and the release magnet valve. v

32. The combination in an electro-pneumatic air brake system of a distributing valve, a release magnet valve controlling the distributing valve and automatically open-' ing the same to atmosphere, a safety'magnet valve controlling the exhaust port of the engineers valve, and awire controlling the supply of energy to the safety magnet valve and the release magnet valve running. through .thetrain and receiving its energy at the rear thereof.

33. The combination in an elect'ro-pneumatic air brake system, of a distributing valve, a release magnet valve controlling the distributing valve and automatically opening the same to atmosphere, a safety magnet valve controlling the'exhaust port of the engineers valve, a release wire supplying energy to the release magnet valve 'and the safety magnet valve, running through the train,and a circuit wire controlling the supply of energy to said release wire running through the train and receiv ing energy atthe rear thereof.

34:. The combination with an automatic air brake system, of a distributing valve, a pressure reservoir connected to the auxiliary reservoir and to the rear of the distributing valve,a control magnet valve control- -matic air brake system, of a distributing :nrvaeve ling the connection hetween the auxiliary reservoir and the pressure reservoir, an application' valve controlling the connection between the pressure reservoir and the distributing valve, a release magnet valve automatically closing the passage between the pressure reservoir and the distributing val e and opening the rear of the distributing valve to the atmosphere, and a release wire supplying energy to both the control magnet valve'and the release magnet valve.

35. In an electro-pneumatic: air brake system, the combination of a cir buit wire running throughthe train and receiving its energy at the rear thereof ,ltontrolling the supply of energy to parts air the electrical side of the system, an engineers valve and a selector switch valve controllingthe eX- haust port of the engineers valve and opening and closing the circuit wire.

36. In an electrically operated air brake system, the combination with a source of air, a brake cylinder and an application magnet valve for controlling the supply of air from said source for applying the brakes, of a release valve and a valve'oper- Hating therewith controlling the air supplied by said application magnet valve.

87. In an electrically operated air brake system, the combination with a source of air, a brake cylinder and an application magnet valve for controlling the supply of air from said source for applying the brakes, of a release valve and a valve operating therewith in the passage from said ap piication magnet valve;

38. In an electrically operated air brake system, the combination with a source of magnet valve for controlling the supply of air from said source for applying the brakes, of a release magnet valve for releasin when deenergized the air supplied by said application magnet valve and a valve operating therewith preventing the supply of air by said application magnet valve when the release magnet valve is deener The combination with an automatic air brake system, of an application magnet valve controlling the supply of air from the auxiliary reservoir for applying the brakes, a release magnet valve when deenergized releasing the air supplied by said application magnet valve, and a valveoperating with GEORGE MACLOSKIE.

Witnesses:

BENJAMIN B. HULL, HELEN Onronn.

' air, a brake cylinder and an application