Electronic pneumatic brake system

An electronic pneumatic brake system for trains which significantly improves brake cylinder pressure build-up time and facilitates essentially instantaneous and simultaneous braking on all cars of the train. The electronic pneumatic brake system includes electronic pneumatic control valves on the cars which individually control the braking on each car or a pack of cars and which are regulated by an electronic pneumatic controller on each car that receives electronic braking and release signals by way of wireless communication from an electronic head end unit on the lead locomotive, or where no head end unit is provided in the locomotive, receives pneumatic braking signals through the brake pipe.

This application claims the benefit of U.S. provisional application Ser. 
No, 06/007,808, filed Nov. 30,1995. 
This invention relates in general to an electronic pneumatic brake system 
for trains, and more particularly to a fail-safe electronic pneumatic 
brake system which provides substantially instantaneous and simultaneous 
application of the brakes on all of the cars which significantly reduces 
brake pressure build-up time as well as braking distances. 
BACKGROUND OF THE INVENTION 
Railroad trains in North America, Europe, and substantial parts of the 
world are equipped with some form of automatic pneumatic brake systems, 
sometimes referred to as air brakes. This strictly pneumatic brake system 
provides a simple, reliable, and generally fail-safe means for permitting 
the engineer, conductor, or train crew to apply the brakes throughout the 
train as well on the locomotive. The automatic pneumatic brake system is a 
continuous power brake system having an air compressor on the locomotive 
connected to a brake pipe extending throughout the train. An automatic 
brake valve is located on the locomotive which the engineer uses to reduce 
or increase air pressure in the brake pipe. The standard automatic brake 
valve has a release position, an initial reduction position, a service 
braking zone, a suppression position, a handle off position, and an 
emergency position. Each car of the train has a control valve which senses 
a "reduction" or "increase" of air pressure in the brake pipe initiated by 
the engineer at the automatic brake valve, and applies or releases the 
brakes according to the "reduction" or "increase" command, respectively. 
The control valves vary in construction and in operating features to suit 
freight or passenger trains. 
While air brakes are used on both freight and passenger trains, the demands 
on each system are quite different due to the length of the train, the 
weight of the train, the speed of the train, and other various factors. 
The length of the train is especially important since air pressure 
reductions in the brake pipe travel at approximately the speed of sound. 
In a long freight train, such as one having one hundred fifty cars and a 
possible length of one and one-half miles, it takes approximately eighteen 
seconds for the air pressure reduction initiated in the locomotive to 
reach the last car in the train. Accordingly, in the prior known automatic 
pneumatic brake systems on freight trains, the brake cylinder pressure 
build-up time has to be carefully retarded in the front cars to prevent 
the last cars of the train, where the brakes have not yet been applied due 
to the signal delay, from running into the front cars with fully developed 
brake cylinder pressure. Consequently, full pressure braking is delayed 
and braking distances are longer. On shorter trains such as passenger 
trains, this is not such a significant problem, even though there is some 
delay between the braking of the first and last cars. 
To solve these problems, electronically controlled pneumatic brake systems 
have been proposed and are currently being tested. For example, Technical 
Services & Marketing, Inc. has proposed and is testing a retrofit 
electronic air brake system disclosed in U.S. Pat. No. 5,355,974. The 
electronically controlled pneumatic brake system generally incorporates 
part of the automatic pneumatic brake system equipment including the brake 
pipe, the reservoir tanks, the brake cylinder(s), and the rigging or 
linkage between the brake cylinder and the brakes. Control of the brake 
cylinder pressure is accomplished through a computer controlled network 
wherein each car is equipped with a control device and the locomotive is 
equipped with a head end unit or a master controller. Generally, in the 
prior known electronically controlled pneumatic brake system, the head end 
unit determines the amount of brake cylinder pressure and sends a 
corresponding signal, including the amount of brake cylinder pressure, to 
each controller. The car control devices act through solenoid controlled 
valves to fill and exhaust the brake cylinder in response to the 
electronic brake cylinder pressure signals issued by the head end unit. 
The brake cylinder pressure on each car is thereby directly controlled by 
the head end unit in response to an electronic braking or release command 
from the engineer. The electronically controlled pneumatic brake system 
provides substantially instantaneous and simultaneous brake signals to all 
of the cars which enables all of the cars to brake at substantially the 
same time (i.e., increasing the rate of brake cylinder pressure build-up). 
The electronically controlled pneumatic brake system also provides the 
possibility of a graduated release of the brakes since the brake cylinder 
pressure on each car is under virtually simultaneous control of the 
engineer. The brakes can be applied, partially released, then reapplied as 
often as necessary, within the ability of the locomotive air compressors 
to replenish reservoirs at the rear of a long train. 
While the general concept of electronically controlled pneumatic brake 
systems has been proposed, there currently are no Association of American 
Railroads (AAR) approved systems which completely, adequately, and safely 
implement an electronically controlled pneumatic brake system installation 
on present passenger or freight trains. To foster development of 
electronic air brake systems, the AAR recently issued a report on 
electronically controlled pneumatic brake systems entitled "UPDATED STATUS 
OF AAR ELECTRIC BRAKE SPECIFICATION" to provide general guidelines for the 
industry in developing electronically controlled pneumatic brake systems 
according to minimum standards and specifications. Accordingly, there is a 
need for a fail-safe electronically controlled pneumatic brake system 
adapted to be installed and work in conjunction with the pneumatic braking 
rigging or equipment on present day freight cars that completely, 
adequately, and safely implements an electronically controlled pneumatic 
brake system and eliminates the problems of the old air brake systems. 
SUMMARY OF THE INVENTION 
The present invention provides a fail-safe electronic pneumatic brake 
system for trains, and particularly for freight trains, which 
significantly reduces brake pressure build-up time and braking distances 
by providing substantially instantaneous, simultaneous, and uniform 
application of brakes on all cars in the train. The electronic pneumatic 
brake system of the present invention further facilitates a substantial 
increase in braking control, provides a graduated release of the braking 
application, increases the uniformity of braking which diminishes 
brake-related damage and extends wheel life, constantly recharges the 
supply reservoir during normal operation including braking applications, 
responds to air pressure reductions in the brake pipe as commonly used in 
freight cars, dramatically reduces brake-induced slack action between the 
cars, decreases the time spent in charging and testing the system during 
set-up thereby reducing terminal delays, and works on three-pack or 
five-pack articulated sets of cars. Additionally, better all-around 
braking of the train provided by the present invention allows the trains 
to run faster and more efficiently. 
In one embodiment of the electronic pneumatic brake system of the present 
invention the system includes an electronic head end unit on the lead 
locomotive, an electronic pneumatic controller on each car or on one car 
of a three-pack or five-pack articulated set, and an electronic pneumatic 
control valve on each car or on one car of an articulated set. The head 
end unit and the controllers may be hard-wired to respond to each other, 
or fitted with transceivers for responding to each other. The control 
valve is attachable to the pipe bracket thereby replacing the ABD, ABDW, 
or other conventional valves on present automatic air brake systems. More 
particularly, the electronic pneumatic brake system of the present 
invention is easily installed on cars having the present automatic air 
brake system equipment by replacing the service and emergency portions of 
the conventional control valve with service and emergency manifolds, 
mounting an electronic pneumatic controller on the car, connecting the 
controller to the electronic pneumatic control valve, removing the release 
rod and the retainer, mounting release buttons on opposite sides of the 
car, and connecting the release buttons to the control valve with a 
suitable air line, such as nylon tubing. 
The electronic pneumatic braking system is operated at the head end unit by 
the engineer on the lead locomotive. After the system is charged, the 
engineer can initiate braking and the level of braking through the head 
end unit which sends an electronic braking signal preferably by wireless 
communication to the controllers on the cars, thereby causing all cars in 
the train to brake substantially instantaneously, simultaneously, and 
uniformly. The electronic signal from the head end unit corresponds to the 
amount of the air pressure reduction in conventional air brake systems, as 
described below. Each electronic pneumatic controller responds to the 
braking signal by calculating the brake cylinder pressure for its car and 
activating the electronic pneumatic control valve to cause an increase in 
brake cylinder pressure. The engineer can release the brakes using the 
head end unit which sends a brake release signal preferably by wireless 
communication to each controller. This signal corresponds to the amount of 
brake pipe pressure increase in conventional brake systems. Each 
controller calculates the amount of release and activates the control 
valve to decrease the brake cylinder pressure and release the brakes. The 
electronic pneumatic brake system of the present invention further has 
electronic and pneumatic emergency braking and release applications which 
back each other up to provide a fail-safe braking system as well as a 
manual brake release mode. 
The present invention thus includes an electronic pneumatic brake system 
having an electronic controller on each car of the train or on one car of 
an articulated set which responds to a head end unit on the locomotive. 
The present invention further includes alternative embodiments of the 
electronic controller and control valve adapted to respond to air pressure 
reductions in the brake pipe as commonly used in freight cars if there is 
no head end unit on the lead locomotive. Specifically, the present 
invention includes alternative embodiments which include a universal 
control valve for use with one or more cars on a train with a locomotive 
having or not having a head end unit, a control valve for use on a center 
car of three-pack or five-pack articulated sets of cars in a train with a 
locomotive having a head end unit, and a universal control valve for use 
on the center car of three-pack or five-pack articulated sets of cars in a 
train with a locomotive having or not having a head end unit. In 
articulated car sets, the present invention further includes a 
non-electronic pneumatic braking unit for use on the additional cars of 
three-pack or five-pack articulated sets of cars. The system of the 
present invention is particularly suitable for long freight trains, but 
could be used on short freight or passenger trains or combination freight 
and passenger trains. 
It is therefore an object of the present invention to provide a unique and 
failsafe electronic pneumatic brake system for trains. 
A further object of the present invention is to provide an electronic 
pneumatic brake system which provides a more uniform application of the 
brake throughout the train due to a more precise control of brake pressure 
and application. 
A further object of the present invention is to provide an electronic 
pneumatic brake system which significantly reduces brake cylinder pressure 
build-up time and dramatically reduces braking distances. 
A further object of the present invention is to provide an electronic 
pneumatic brake system which provides substantially instantaneous and 
simultaneous braking on all cars of the train that facilitates a 
substantial decrease in braking delay. 
A still further object of the present invention is to provide an electronic 
pneumatic brake system which incorporates the service and emergency 
braking applications into one system. 
A further object of the present invention is to provide an electronic 
pneumatic brake system which is easily installed and which utilizes 
substantially all of the present automatic air brake system rigging or 
equipment. 
A further object of the present invention is to provide an electronic 
pneumatic brake system which provides for graduated release of the train 
brakes. 
A further object of the present invention is to provide an electronic 
pneumatic brake system which constantly recharges the supply reservoir 
during normal braking conditions. 
A still further object of the present invention is to provide an electronic 
pneumatic brake system which is adapted to respond to air pressure 
reductions in the brake pipe as commonly used in freight cars. 
A yet further object of the present invention is to provide an electronic 
pneumatic brake system for three-pack or five-pack articulated car sets. 
Other objects, features and advantages of the invention will be apparent 
from the following detailed disclosure, taken in conjunction with the 
accompanying sheets of drawings, wherein like reference numerals refer to 
like parts.

DESCRIPTION OF THE INVENTION 
Referring now to the drawings, and particularly to FIGS. 1 and 16, the 
electronic pneumatic brake system of the present invention, generally 
indicated by numeral 20, is adapted for installation on existing freight 
cars 22 (shown in phantom) and works in conjunction with substantially all 
of the brake rigging or equipment of the present day automatic air brake 
system. The electronic pneumatic braking system of the present invention 
incorporates the brake or supply pipe 24 which runs the length of the 
train. On each car, the brake pipe 24 is connected at each end to the 
adjacent car in the train by suitable couplings. The brake pipe 24 
distributes compressed air from a compressor (not shown) on the locomotive 
(not shown) throughout the entire train. In current automatic air brake 
systems, as well as in the present invention, the air pressure in the 
brake pipe may range from approximately 70 to 110 psig. 
The compressed air travels from the brake pipe 24 through a branch pipe tee 
26 in the brake pipe to a combined dirt collector and cut out cock 28 and 
then to the electronic pneumatic control valve 30 which replaces the 
conventional valve on present freight cars. The electronic pneumatic 
control valve 30 directs the compressed air to a supply reservoir 32 which 
combines the auxiliary and emergency reservoirs of the old brake systems. 
The supply reservoir stores the compressed air for service as well as 
emergency braking applications. The control valve 30 is operated by an 
electronic pneumatic controller 34 mounted on the car. The controller 34 
and like controllers on other cars in turn may be operated through 
radiotelemetry by an electronic head end unit 36 mounted on the lead 
locomotive or be hard-wired to the head end unit. FIG. 16 illustrates the 
head end unit 36 for a lead locomotive and controllers 34a and 34b for 
cars in the train, all of which are fitted with transceivers that allow 
them to communicate with each other. The control valve 30 directs 
compressed air from the supply reservoir 32 to the brake cylinder 40 in 
accordance with signals issued by the head end unit 36 to the controller 
34 as well as in emergency braking applications. The air pressure directed 
to the brake cylinder 40 causes the brake cylinder to apply the brakes 
through a series of linkages in a conventional manner, as generally 
illustrated in FIG. 1. The brakes may also be applied manually in a 
conventional manner. 
The electronic pneumatic air brake system 20 of the present invention 
therefore utilizes the components of the old pneumatic braking system 
except for the addition of the head end unit 36 on the lead locomotive, 
the addition of an electronic controller 34 on each car, the addition of 
brake release buttons on each car, the replacement of the current 
conventional valve with the electronic pneumatic control valve 30 on each 
car, and the removal of the release rod and retainer from each car. More 
particularly, the conventional valve includes a standard pipe bracket 42, 
a service portion (not shown) attached to the service side of the pipe 
bracket, and an emergency portion (not shown) attached to the emergency 
side of the pipe bracket. The present invention utilizes the pipe bracket 
42, replaces the service portion with a service side manifold 44 attached 
to the service side of the pipe bracket 42, and replaces the emergency 
portion with an emergency side manifold 46 attached to the emergency side 
of the pipe bracket 42. It should therefore be appreciated that the 
refitting of the cars with the electronic pneumatic brake system of the 
present invention simply requires removing the old service and emergency 
portions from the pipe bracket, removing the retainer and release rod, 
attaching the new manifolds to the pipe bracket, mounting the electronic 
pneumatic controller on the car, mounting the brake release buttons on 
opposite sides of the car, connecting the release buttons to the manifold 
preferably using nylon tubing, and connecting the controller to the 
pneumatic control valve. A rubber gasket or other suitable gasket is used 
between the pipe bracket and each manifold to create an airtight 
connection. A standard freight car can thus be refitted with the 
electronic pneumatic brake system relatively quickly. This is important 
since there are approximately 1.2 million freight cars in service in the 
United States. 
The electronic pneumatic air brake system 20 is preferably used on trains 
controlled by a lead locomotive equipped with an electronic head end unit 
36 mounted in the engineer's control panel. The electronic head end unit 
(HEU), which may feature touch screen control technology, is powered 
preferably by a separate battery in the locomotive which is constantly 
recharged by the locomotive and is adapted to send commands to and receive 
information from the electronic pneumatic controller 34 on each car. More 
particularly, the head end unit 36 preferably includes a broad-band radio 
transceiver operating at 2.4 to 2.9 gigahertz or 915 to 919 megahertz 
which transmits information at two megabytes per second to suitable 
transceivers on the controllers. These bands are preferable because they 
have been designated by the FCC for use to transmit data, and do not 
require a license. Further, this type of radio is essentially jamproof. 
Alternatively, the transmission between the head end unit and the 
controllers may be by any wireless method or the head end unit could be 
hardwired to each controller. The signal from the head end unit to the 
controllers sent by radio communications to all of the controllers in the 
train is substantially instantaneous and simultaneous. 
During initial set-up or initializing and charging of the system at a 
terminal, the head end unit establishes communication with each controller 
and is loaded with the serial number and identification of each car in the 
train, the weight of the car, and other desirable information. The head 
end unit and the controllers are also loaded with a security code to 
prevent random signals from activating the controllers. While each 
controller hears the HEU transmission, a given controller will not respond 
unless the correct identification and security code for that car is also 
received. The given controller is adjusted in accordance with the weight 
information received by the HEU and transmitted to the controllers during 
setup for later calculating braking ratios. Thereafter, each controller 
sets the necessary braking force to match the car weight. Alternatively, 
each car could be equipped with its own weight-measuring device which 
provides weight information to the controller on that car. 
Since not every train will have a head end unit, the electronic pneumatic 
braking system of the present invention has alternative embodiments which 
include the combination of electronic controllers and electronic control 
valves adapted to respond to brake pipe pressure reductions as commonly 
used in freight cars. While discussed in more detail below, to accomplish 
this, there are eight different embodiments of the electronic pneumatic 
control valve and four different embodiments for the electronic controller 
of the present invention. The eight different embodiments for control 
valves include: (1) two electronic pneumatic control valves for use on a 
car in a train with a locomotive having a head end unit, as illustrated in 
FIGS. 3 and 10; (2) two universal electronic pneumatic control valves for 
use on a car in a train with a locomotive having or not having a head end 
unit, as illustrated in FIGS. 5 and 12; (3) two electronic pneumatic 
control valves for use on the center car of three-pack or five-pack 
articulated sets of cars in a train with a locomotive having a head end 
unit, as illustrated in FIGS. 6 and 13; and (4) two universal electronic 
pneumatic control valves for use on the center or master car of three-pack 
or five-pack articulated sets of cars on a train with a locomotive having 
or not having a head end unit, as illustrated in FIGS. 8 and 15. 
Additionally, the electronic pneumatic brake system of the present 
invention includes two non-electronic pneumatic braking units for use on 
the additional or slave cars of three-pack or five-pack articulated sets 
of cars, as illustrated in FIGS. 7 and 14. The use of these control valves 
in the electronic pneumatic braking system depends on the make-up of the 
train and the locomotive to which the cars are connected, as discussed 
below. 
Referring now to FIGS. 1 and 2, the electronic pneumatic controller 34 is 
suitably mounted on each car preferably close to the pipe bracket and is 
hardwired by a cable to the electronic pneumatic control valve 30. Each 
controller has a central processing unit (CPU) or microprocessor 47 which 
includes a conventional analog to digital converter for converting the 
analog signals received from the control valve 30 into digital signals 
which the processor monitors to regulate the control valve. The central 
processing unit is powered by a power supply 48, preferably consisting of 
a twelve-volt battery which is charged by an alternator or generator which 
may be mounted on one of the axles of the car. Other suitable methods of 
recharging the battery may also be used. The controller has a broad-band 
radio transceiver 49 operating at 2.4 to 2.9 gigahertz or 915 to 919 
megahertz or other suitable band and which can transmit information to the 
head end unit and other controllers on the train at two megabytes per 
second. The controller is also connected to a series of transducers and 
solenoids in the control valve 30, as described below. 
The electronic pneumatic brake system of the present invention has multiple 
stages or applications including an initial set-up and charging stage, a 
service or braking application, various types of emergency braking 
applications, braking release applications, an emergency braking release 
application, and a manual braking release application. 
CHARGING 
Referring now to FIGS. 2 and 3, the electronic pneumatic control valve 30 
and the electronic pneumatic controller 34 are adapted to be used only on 
trains with a locomotive having a head end unit which communicates with 
electronic controllers 34 on each of the cars in the train. To charge the 
system, compressed air from the compressor on the locomotive travels 
through the automatic brake valve (not shown) in the locomotive and along 
the brake pipe 24 to each of the cars. In each car, the compressed air 
travels through the standard dirt collector/cut-out cock 28 and through 
port 50 (labeled "PORT 1") into the pipe bracket 42. The pipe bracket 42 
is the same as is used with current valves and includes four or more ports 
on each side. The control valve 30 utilizes selected ports, air chambers, 
and passageways of the pipe bracket. In the pipe bracket 42, the 
compressed air from the brake pipe passes through a pipe bracket filter 51 
and is directed to the service and emergency sides of the pipe bracket. 
Air at the service side of the pipe bracket 42 travels into a service side 
manifold 44 (labeled "MANIFOLD-1B") and to a conventional spring biased 
normally closed vent valve 52. The vent valve 52 is rate sensitive and 
responds or opens when it detects an emergency pressure decrease in the 
brake pipe to further vent the brake pipe. During charging, the vent valve 
52 is closed, and it remains closed during normal operation. Air at the 
emergency side of the pipe bracket 42 travels into the emergency side 
manifold 46 (labeled "MANIFOLD-1A") and through manifold filter 54 and 
into a supply line 55. Pipe bracket filter 51 is a conventional filter 
which cleans solid particles such as dirt and pipe scale from the air in 
the brake pipe. Manifold filter 54 is a porus stainless steel disc filter 
which additionally filters out solid particles. 
After filtering, the compressed air travels in the supply line or 
passageway 55 to an emergency charge valve 56 (labeled "EMER. CHARGE 
VALVE"), a check valve 58 (labeled "CHECK VALVE 1"), a check valve 60 
(labeled "CHECK VALVE 1A"), a pressure transducer or sensor 62 (labeled 
"T1"), an emergency assuring valve 64 (labeled "E.A.V. VALVE"), and a 
release control valve 100 (labeled "REL. CONTROL VALVE"). The emergency 
charge valve 56 is a normally open conventional spring-biased pressure 
actuated valve wherein the pressure in the supply line 55 holds the 
emergency charge valve closed during charging and normal operation. The 
check valves 58 and 60 are normally closed conventional spring-biased 
valves, connected on one side to the brake pipe 24 and on the other side 
to the supply reservoir 32 and valve supply chamber 92 respectively, and 
which permit the flow of air in only one direction toward the supply 
reservoir and valve supply chamber 92. The check valves 58 and 60 are 
opened during charging of the system but will not allow air to flow from 
the supply reservoir or valve supply chamber to the brake pipe. Thus, 
these valves are open only when the pressure on the brake pipe side 
exceeds the pressure on the reservoir and chamber side. The emergency 
assuring valve 64 is a dual cartridge valve having a conventional 
spring-biased valve wherein the pressure in the supply line 55 closes the 
emergency assuring valve during charging of the system and holds it closed 
in normal operation. The emergency assuring valve 64 also includes a 
diverter valve for directing the air pressure to the choke 120 during 
pneumatic emergencies, as discussed below. 
The release control valve 100 is a double cartridge unit which includes a 
brake or supply pipe pressure actuated spring-biased valve cartridge or 
part and a controller actuated pilot line exhaust valve cartridge or part. 
These cartridges or parts are connected in series. The pressure actuated 
valve part may be disposed on either side of the solenoid actuated valve 
part relative to the exhaust and pilot line. The pilot line exhaust valve 
is solenoid actuated and held open during charging and brake release to 
vent the pilot line 104 and closed during braking. The pressure actuated 
valve is connected to the supply line 55 and thus the brake pipe 24 and is 
maintained open by the normal air pressure in the brake pipe following 
charging and during normal operation. Specifically, if the brake pipe 
pressure is at or substantially at the normal pressure, the pressure 
actuated valve will be held open by that normal pressure, wherein the 
solenoid actuated valve part controls the connection of the pilot line to 
exhaust. The pressure actuated valve closes under spring pressure to block 
any exhausting of the pilot line during emergency braking caused by a drop 
in supply pipe pressure. Thus, where the solenoid actuated valve may 
malfunction due to controller malfunction and open the pilot line to 
exhaust, the pressure actuated valve part of the release control valve 
assures braking in an emergency situation where the brake/supply pipe 
pressure is lost or drops to an emergency level. 
The transducer 62 is a conventional analog device which converts air 
pressure into an analog electric signal. The transducer sends this signal 
to the central processing unit in the electronic controller 34 which 
converts the analog signal into a digital signal using a standard 
analog-to-digital converter. With respect to the transducer 62 and other 
transducers, it should be appreciated that the analog-to-digital converter 
may be built into the transducer if desired. The controller therefore 
monitors the air pressure of the supply line 55 as well as the pressure in 
the brake pipe 24. 
The compressed air flows through check valve 58 into reservoir supply line 
or passageway 65 and to relay valve 66 (labeled "RELAY VALVE"), emergency 
charge valve 56, transducer 68 (labeled "T2"), reset valve 70 (labeled 
"RESET VALVE"), release button-type valves 72 and 74 (labeled "REL BTN"), 
and port 76 (labeled "e-3") in the pipe bracket 42. The relay valve 66 is 
a normally closed pressure actuated valve which remains closed during 
charging and may be spring biased. When the relay valve 66 is in the 
closed position, the relay valve exhaust 67 is open, thereby venting to 
atmosphere the brake cylinder 40, as discussed below. The reset valve 70 
is a normally closed conventional solenoid actuated valve. The release 
button-type valves 72 and 74 are provided for trainmen to manually release 
the brakes on the car. These valves are pressure and manually closable and 
manually openable mechanical valves physically mounted on opposite sides 
of the car. The release button valves are closed or in the "out"position 
during charging of the system and openable by trainmen when manually 
releasing the braking on the car. 
The pipe bracket 42 directs compressed air from a port 76 through a flange 
fitting port 78 (labeled "PORT 2") at the rear face of the pipe bracket 42 
and into an emergency reservoir 80 where the compressed air is stored. The 
pipe bracket 42 also directs compressed air from port 76 through port 82 
(labeled "e2") into manifold 44, which in turn directs the air back into 
pipe bracket through port 84 (labeled "a"). Thus, ports "e2" and "a" are 
connected together by Manifold-1B. The pipe bracket further directs the 
air from port "a" through a flange fitting port 86 (labeled "PORT 5") at 
the rear face of the pipe bracket and into an auxiliary reservoir 88 where 
the compressed air is stored. Accordingly, the conventional 
two-compartment auxiliary and emergency reservoirs that are used on 
present freight equipment are combined to form the single supply reservoir 
32 in the present invention. 
The combination of the auxiliary and emergency storage compartments 80 and 
88 into one supply reservoir 32 simplifies the system and provides better 
operation in addition to eliminating the need of the control valve to 
maintain more than one system. The air stored in the supply reservoir 32 
provides compressed air to the relay valve 66 via the reservoir supply 
line 65 for use in applying the brakes, as described below. The pressure 
of the air in the supply reservoir 32 is monitored by a transducer 68 
which sends a signal to the central processor of the electronic controller 
34. The supply reservoir will charge at a rate faster than with previous 
equipment because of the substantially direct connection between the brake 
pipe 24 and the supply reservoir 32, but not so fast as to rob the brake 
pipe and other reservoirs in the train of air. The maximum air pressure in 
the supply reservoir is equal to the maximum air pressure carried in the 
brake pipe. 
The compressed air also flows through check valve 60 into a pilot supply 
line or passageway 90 and to the valve supply volume or chamber 92 located 
in the pipe bracket 42, the emergency charge valve 56, an application 
valve 94 (labeled "APPL VALVE"), a transducer 96 (labeled "T3") and a 
regulating valve 98 (labeled "REG. VALVE"). The valve supply volume or 
chamber 92 is a relatively small air storage chamber in the pipe bracket 
42 previously called the quick action chamber or the "QAC". Since the 
valve supply volume is relatively small, during charging the valve supply 
volume 92 will immediately fill or build-up to the pressure in the brake 
pipe 24. The application valve 94 is a solenoid actuated valve which is 
held closed during system charging. The regulating valve 98 is a normally 
open conventional spring-biased pressure actuated valve which is manually 
set at a predetermined pressure level based on conventional air pressure 
levels and is open during charging and normal operation. If during a 
pneumatic emergency, the pressure in the pilot line 104 exceeds the 
predetermined pressure in the regulating valve, the regulating valve 
exhaust 99 will open, venting the pressure in the pilot line until it is 
at the regulating valve predetermined pressure level. The valve supply 
volume air pressure is monitored by transducer 96 which sends a signal to 
the central processor in the electronic controller 34. 
The electronic pneumatic control valve 30 further includes a cylinder 
release valve 102 (labeled "CYL. REL. VALVE") connected to the pilot line 
or passageway 104. The cylinder release valve 102 is a normally open 
spring-biased pressure actuated valve which is open during charging to 
connect the pilot line 104 between the cylinder release valve 102 and a 
pilot port 106 on the relay valve 66. The cylinder release valve 102 has 
an exhaust 105 which is closed when the cylinder release valve 102 is 
open. The pilot line 104 has a substantially small diameter to allow for a 
quick build-up of air pressure, as discussed below. A transducer 108 
(labeled "T4") monitors the pressure in the pilot line 104 and sends a 
signal to the central processor unit 47 in the electronic controller 34. A 
transducer 110 (labeled "T5") monitors the air pressure in the brake 
cylinder line or passageway 111 which is connected to the brake cylinder 
pipe 38 and sends a signal to the central processor unit 47 in the 
electronic controller 34. By monitoring the signals from transducers 
"T1"to "T5", the electronic pneumatic controller 34 monitors the pressure 
in the brake pipe, the brake cylinder, and all air passageways in the 
control valve 30. 
During train make-up and charging, and after the brake pipe pressure has 
increased to about 40 psig, the controller 34 may be programmed to 
momentarily open the solenoid actuated reset valve 70 to feed compressed 
air to each release button valves 72 and 74 causing resetting and movement 
to the closed or "out" positions if not already closed. 
The following chart provides a summary of the main valves and their 
positions during the charging of the electronic pneumatic air brake system 
with control valve 30. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) CLOSED 
Relay Valve Exhaust (67) 
OPEN 
Reset Valve (70) CLOSED 
Release Button Valves (72, 74) 
CLOSED ("OUT" POSITION) 
Application Valve (94) 
CLOSED 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
OPEN 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release Valve 
Exhaust (105) CLOSED 
______________________________________ 
After charging, when the pressure in the brake pipe 24 equals that of the 
supply reservoir 32, the check valves will close. The relay valve is 
available from Bendix Brakes, a division of Allied Signal Inc., and the 
other valves are available from Clippard Instrument Laboratory, Inc. as 
standard valves or custom-made valves. 
SERVICE APPLICATION 
To initiate braking, the engineer in the lead locomotive sets the head end 
unit to the level of braking desired. The head end unit transmits a 
signal, including the amount of the pressure reduction, to the electronic 
controller 34 on each car of the train. The signal for a service 
application from the head end unit corresponds to the air pressure 
"reduction" in the brake pipe in old air brake systems which the engineer 
initiates with the automatic brake valve. For instance, if the brake pipe 
pressure is initially set at 90 psig, the head end unit could send a "80 
psig"signal to the controllers which would correspond to a brake pipe 
pressure reduction of 10 psig in a conventional air brake system, even 
though the brake pipe pressure does not actually change. 
Upon receipt of the electronic braking signal from the head end unit, the 
controllers 34 will calculate the brake cylinder pressure for each car in 
reference to the amount of the reduction which corresponds to the level of 
braking desired, and the weight of the car which is loaded into the 
controller by the head end unit during set-up and charging. After 
calculating the brake cylinder pressure needed, the controller 34 first 
momentarily opens the reset valve 70 directing air pressure to the release 
button valves 72 and 74 to insure that those valves are closed or in the 
"out" position. This check occurs each time the engineer increases or 
decreases the brake application using the head end unit to insure that the 
brakes throughout the train are available. This protects against 
situations where the brakes are released by these valves, such as by a 
trespasser or inadvertently by a trainman. This feature also conserves 
time during train make-up at initial terminal or during switching 
movements as manual resetting is eliminated. When the reset valve closes, 
it will exhaust the air directed toward the release button valves through 
the reset valve exhaust 71. 
The controller 34 then sends a signal to the release control valve 100 
causing the solenoid actuated valve therein to close. Since the pressure 
in the brake pipe remains constant, the pressure actuated valve in the 
release control valve remains open. The controller simultaneously sends a 
signal to the solenoid actuated application valve 94 causing the 
application valve to open. The opening of the application valve sends air 
pressure from the valve supply volume 92 via the pilot supply line 90 
through the application valve to the pilot line to increase the pressure 
in the pilot line 104 to the pressure calculated by the controller. The 
pressure in the pilot line rapidly increases because the pilot line has a 
substantially small diameter. This pressure build-up in the pilot line, 
which is communicated to the pilot port 106 of the relay valve 66 through 
the open cylinder release valve 102, pneumatically causes the relay valve 
66 to open, thereby directing air pressure from the supply reservoir 32 
into the brake cylinder line 111 via the reservoir supply line 65. As the 
relay valve 66 opens, the relay valve exhaust 67 closes. The air pressure 
from the supply reservoir develops in the brake cylinder line 111 and 
through port 112 (labeled "C") in the pipe bracket 42. This pressure 
travels through the flange fitting at port 114 (labeled "PORT 3") of the 
pipe bracket and into the brake cylinder pipe 38. The pressure in the 
brake cylinder pipe 38 thus equals that of the pilot line 104. The 
pressure in the brake cylinder pipe 38 is communicated to the brake 
cylinder 48 which applies the brakes in response to the amount of pressure 
in the pilot line. It should be appreciated that when the air pressure in 
the valve supply volume is directed to the pilot line and the air pressure 
in the supply reservoir is directed to the brake cylinder, the check 
valves will open due to the pressure difference to begin recharging these 
volumes. The following chart provides a summary of the valve positions 
during service braking. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) OPEN 
Relay Valve Exhaust (67) 
CLOSED 
Reset Valve (70) OPENED (MOMENTARILY) 
Release Button Valves (72, 74) 
CLOSED (OUT) 
Application Valve (94) 
OPEN 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
CLOSED 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release 
Valve Exhaust (105) 
CLOSED 
______________________________________ 
As the pressure in the pilot line 104 reaches the value set by the 
controller 34, the controller will close the application valve 94. 
Likewise, as the pressure in the brake cylinder 40 reaches the pressure in 
the pilot line 104 which is the pressure set by the controller, the relay 
valve 66 will assume a lap condition in which the relay valve 66 and the 
relay valve exhaust 67 are closed, thereby maintaining the pressure to the 
brake cylinder constant to provide continued braking at that level. The 
following chart provides a summary of the valves positions when the 
desired level of braking is achieved and maintained and a lap condition 
occurs. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (67) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) CLOSED ("LAP" CONDITION) 
Relay Valve Exhaust (67) 
CLOSED ("LAP" CONDITION) 
Reset Valve (70) CLOSED 
Release Button Valves (72, 74) 
CLOSED (OUT) 
Application Valve (94) 
CLOSED 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
CLOSED 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release 
Valve Exhaust (105) 
CLOSED 
______________________________________ 
The pressure in pilot line 104 is constantly monitored by transducer T4 to 
maintain the set pressure within .+-.1 psig as set by the controller 34. 
If the pressure in the pilot line drops, the application valve 94 may be 
reopened to increase the pressure in the pilot line. If the pressure in 
the pilot line increases, the solenoid actuated valve of the release 
control valve 100 may be opened to decrease the pressure in the pilot 
line. Transducer T5 is used to ascertain that the pressure in the brake 
cylinder line 111 and thus the brake cylinder 40 is within .+-.1 psig of 
the pilot line pressure and the set braking pressure. If the brake 
cylinder pressure for any reason should deviate from the pilot line 
pressure, the relay valve 66 will open to supply air from the supply 
reservoir 32 to the brake cylinder 40 to maintain the brake cylinder 
pressure substantially equal to the pilot line pressure. This level of 
control is maintained by the electronic controller 34 at the pilot line 
104 by the relay valve 66 during all stages of brake applications 
regardless of the duration of the application and will be maintained 
against increased piston travel due to brake shoe wear while descending 
grades. Thus, a more uniform and consistent braking force is achieved than 
is possible with present standard air brakes on freight equipment due to 
this precise control of the air pressure to the brake cylinder. 
If additional braking is required, the head end unit sends a signal to the 
electronic controllers throughout the train. For example, if the initial 
charging brake pipe pressure was 90 psig, and the first braking signal 
from the head end unit is 80 psig, the next signal from the head end unit 
may be 75 psig. This command for additional brake cylinder pressure is 
calculated by the controller 34, and the pressure in the pilot line 104 is 
increased by opening the application valve 94, thereby repeating the 
process. The action as described above may be repeated in reference to 
braking or "reduction" signals up to a full service brake cylinder 
pressure in proportion to the maximum pressure carried in the brake pipe 
during initial charging. 
It should be appreciated that since there is no actual decrease in the 
pressure of the brake pipe 24 during normal braking applications, the 
supply reservoir 32 and the valve supply volume 92 in the control valve 
are constantly re-charged by the brake pipe through the check valves 58 
and 60. 
SERVICE RELEASE 
To fully release the brakes, the engineer in the lead locomotive sets the 
electronic head end unit 36 to the appropriate position. The head end unit 
sends a signal to the controller on each car to release the brakes. The 
signal to release the brakes from the head end unit corresponds to an air 
pressure "increase" in the brake pipe as in the old pneumatic systems 
which the engineer initiates by moving the automatic brake valve to the 
release position. Using the previous example, the head end unit would send 
a "90 psig"signal to the controllers to release the brakes. Upon receipt 
of the brake release signal from the head end unit, the controller 34 will 
close the application valve 94 if it is not already closed and open the 
solenoid actuated valve of the release control valve 100 to exhaust the 
pilot line 104 pressure to atmosphere. As the release control valve 100 is 
opened and the pressure in the pilot line is vented, the relay valve 66 
will return to the closed position, thereby exhausting the brake cylinder 
pressure by venting the brake cylinder line 111 to the atmosphere through 
the relay valve exhaust 67. The following chart provides a summary of the 
valves positions during the full release of braking. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) CLOSED 
Relay Valve Exhaust (67) 
OPEN 
Reset Valve (70) CLOSED 
Release Button Valves (72, 74) 
CLOSED (OUT) 
Application Valve (94) 
CLOSED 
Regulating Valve (98) OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
OPEN 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release 
Valve Exhaust (105) CLOSED 
______________________________________ 
If it is desired to release the train's brakes in steps, such as a 
graduated release, the engineer must accordingly set the head end unit. 
Again, using the previous example, the engineer could set the head end 
unit to send an "85 psig"signal. This corresponds to the engineer stopping 
the "increase" of the brake pipe pressure in the present pneumatic brake 
systems. This command from the head end unit will be acted upon by the 
controller by opening and closing the solenoid actuated valve of the 
release control valve 100 to reduce the pressure in the pilot line 104 to 
the desired level as sensed by transducer 108. After the solenoid actuated 
valve of the release control valve closes, the relay valve 66 will exhaust 
the brake cylinder line air pressure only until the pressure in the brake 
cylinder line 111 equals the pressure in the pilot line 104. When the 
pressure in the brake cylinder line 111 equals the pressure in the pilot 
line 104, the relay valve 66 will again assume a lap condition, thereby 
maintaining the pressure to the brake cylinder constant to provide 
continued braking at that level. The brake cylinder 40 will hold at the 
pressure determined by the controller based upon the command sent by the 
head end unit. This condition is a pressure maintaining "lap" condition, 
such that any leakage at the brake cylinder, piping, or increased piston 
travel caused by brake shoe wear will again be nullified. 
The engineer in the locomotive may send braking signals or release signals 
at his or her discretion. Thus, with the electronic control valve of the 
present invention, the engineer may roam through various brake cylinder 
pressures on all cars in the train evenly as terrain or road conditions 
warrant. Since the supply reservoir 32 and the valve supply volume 92 on 
the cars are constantly re-charged from the brake pipe 24 during service 
braking application, there is little danger of running out of air if the 
brake system use is within normal parameters. If the system is taken 
outside of the normal parameters causing a dangerously low air pressure in 
the supply reservoirs throughout the train as sensed by transducer 68, the 
head end unit is signaled by the controllers that this is occurring, and 
either a penalty full service braking application or an electronic 
emergency braking application will take place stopping the train until the 
condition is corrected. If at any time the brake system on a given car or 
cars becomes defective, an alarm will sound at the head end unit in the 
locomotive to warn the engineer. The engineer may electronically cut out 
the defective brake system or systems without stopping the train until the 
train reaches a terminal and the defective systems are fixed. 
EMERGENCY APPLICATION 
Emergency brake applications are available throughout the train at any time 
via electronic or pneumatic communications, or both. An electronic 
initiated emergency brake application will occur when the engineer 
initiates an emergency brake application on the head end unit. In an 
electronic initiated emergency braking application, the engineer in the 
lead locomotive sets the head end unit to an emergency braking position 
and the head end unit sends a signal to the controllers throughout the 
train that an electronic emergency braking application has been initiated. 
When the emergency command is sent out by the head end unit, all of the 
controllers which receive the emergency electronic braking signal will 
relay this command to the other controllers throughout the train for 
backup purposes. After receiving the electronic emergency command, the 
controller will calculate the cylinder brake pressure and momentarily open 
the reset valve 70 to insure that the release button valves 72 and 74 are 
closed. The controller will close the solenoid actuated valve of the 
release control valve 100 and open the application valve 94 to increase 
the air pressure in the pilot line 104 to an emergency application 
pressure at an emergency rate. For instance, when the initial charge is 90 
psig in the brake pipe, a signal of "0 psig" sent by the head end unit 
will indicate an emergency braking application. The emergency level air 
pressure will be communicated to the brake cylinder 40 via the relay valve 
66, as described above. The final brake cylinder pressure will be at least 
approximately twenty percent higher than the pressure available with a 
full service brake application. The final braking pressure is, of course, 
dependent upon the charge carried in the brake pipe. The build-up of 
emergency brake cylinder pressure is applied substantially 
instantaneously, simultaneously, and uniformly on each car throughout the 
train. Thus, when there is an electronic emergency application, no staged 
or staggered brake cylinder build-up is necessary as with known pneumatic 
air brake systems. Since this emergency braking application is of the 
electronic initiated type, there is no decrease in the brake pipe 
pressure, and the brake pipe will not need to be vented to atmosphere. 
Rather, the brake pipe will be available to constantly replenish the 
supply reservoir 32 and the valve supply chamber 92 during the emergency 
braking application. The following chart provides a summary of the valve 
positions during the electronic initiated emergency braking application. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) OPEN 
Relay Valve Exhaust (67) 
CLOSED 
Reset Valve (70) OPENED (MOMENTARILY) 
Release Button Valves (72, 74) 
CLOSED ("OUT" POSITION) 
Application Valve (94) 
OPEN 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
CLOSED 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release 
Valve Exhaust (105) 
CLOSED 
______________________________________ 
A pneumatic initiated emergency will occur when the engineer physically 
moves the automatic brake valve to the emergency position which opens the 
brake pipe and vents the brake pipe to atmosphere or when the conductor, 
fireman, or head brakeman opens the 1 1/4 inch conductor's valve, or when 
a crew member physically opens a conductor's valve on a car of the train, 
thereby venting the brake pipe to atmosphere. Further, a pneumatic 
initiated emergency brake application will occur when the train breaks in 
two, the brake pipe breaks, or a hose bursts. 
In a pneumatic initiated emergency braking application, the air pressure in 
the brake pipe 24 physically reduces at an emergency rate. The first 
controller 34 which detects this rate of reduction will apply the brake on 
the car it is monitoring in both an electronic emergency sequence as 
described above as well as a pneumatic emergency sequence as described 
below. At the same time, the controller will relay to the other 
controllers in the train and the head end unit that an emergency braking 
application is occurring. Once this command is picked up by the other 
controllers and the head end unit, they will repeat the emergency braking 
command, thus assuring that all of the controllers in the train receive 
the command. This will place all of the cars in the train into an 
electronic emergency braking application mode. This electronic emergency 
braking application will take place in all the cars in addition to the 
pneumatic emergency braking application which is communicated by pneumatic 
means along the brake pipe. 
If there is a failure in the electronic communication of the emergency 
braking system, all of the cars can still receive the emergency braking 
signal through pneumatic communication. More particularly, the loss of air 
pressure in the brake pipe 24 at an emergency rate will be detected by the 
vent valve 52 causing it to open, thereby venting the brake pipe 55 to 
atmosphere. This venting on each car will further propagate the reduction 
of air pressure in the brake pipe serially throughout the train. 
A pneumatic emergency causes a two-stage braking application. In the first 
stage, the controller which senses the pressure reduction through 
transducer 62 will momentarily open the reset valve 70 to connect the 
supply reservoir to the release button valves 72 and 74 to close these 
valves if they are open, and close the solenoid actuated pilot line 
exhaust valve part of the release control valve 100. As the brake pipe 
pressure vents, the pressure in the supply line 65 will drop at an 
emergency rate. The emergency rate loss of supply line pressure to the 
pressure actuated spring-biased valve part of the release control valve 
100 will allow the spring to close this valve part and block the pilot 
line exhaust to assure the pilot line is closed and not venting to 
atmosphere. Thus, since the pressure actuated valve closes under 
spring-biasing action, it blocks or renders redundant the solenoid 
actuated valve and thus provides a failsafe system for closing the release 
control valve 100 in pneumatic emergency situations where there may be a 
failure or malfunction of the controller that would open the pilot line 
exhaust valve part of the release control valve. 
The drop in pressure in the supply line will also cause the emergency 
charge valve 56 to open which connects the supply reservoir 32 to the 
valve supply chamber 92, thus insuring the maintenance of adequate 
pressure in chamber 92. The check valves 58 and 60 will close due to the 
difference in pressure in the supply line 55 as compared to the reservoir 
supply line 65 and the pilot supply line 90, respectively. The drop in 
pressure in the supply line 55 and brake pipe 24 will also open the 
emergency assuring valve 64 which directs air pressure from the regulating 
valve 98 directly to the pilot line 104. The pressure build-up in pilot 
line 104 will cause the relay valve 66 to open, thereby closing the relay 
valve exhaust 67 and allowing pressure build-up in the brake cylinder 40, 
as discussed above. This first stage of the two-stage air pressure 
build-up in the pilot line 104 and the brake cylinder occurs in 
approximately one and one-half seconds. 
The following chart provides a summary of the valve positions during this 
first stage of the pneumatic initiated emergency braking application. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) OPEN 
Emergency Charge Valve (56) 
OPEN 
Emergency Assuring Valve (64) 
OPEN (ONLY TO PILOT LINE) 
Relay Valve (66) OPEN 
Relay Valve Exhaust (67) 
CLOSED 
Reset Valve (70) OPENED (MOMENTARILY) 
Release Button Valves (72, 74) 
CLOSED ("OUT" POSITION) 
Application Valve (94) 
CLOSED 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
Solenoid Pilot Line Exhaust Valve 
CLOSED 
Pressure Actuated 
Spring-Biased Valve 
CLOSED 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release 
Valve Exhaust (105) 
CLOSED 
______________________________________ 
After the pilot line pressure builds to 15 psig during the first stage, the 
second stage of pressure build-up will be initiated. The emergency 
assuring valve 64, and specifically the diverter valve will sense the 
pressure build-up of approximately 15 psig in the pilot line which will 
cause the diverter valve to divert the air pressure through choke 120 
instead of directly to the pilot line 104. The remaining pressure will 
build up at the same rate as with present pneumatic freight equipment. 
This two-stage build-up is necessary to coincide with present emergency 
braking application rates and to guard against in-train buffing forces 
during a pneumatic emergency. While the first stage of this build-up 
occurs in approximately one and one-half seconds, the second stage of 
pressure build-up occurs in approximately four and one-half seconds 
through the choke 120 to the pilot line 104. The following chart provides 
a summary of the valve positions during the second stage of the pneumatic 
emergency build-up. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) OPEN 
Emergency Charge Valve (56) 
OPEN 
Emergency Assuring Valve (64) 
OPEN (ONLY TO THE CHOKE) 
Relay Valve (66) OPEN 
Relay Valve Exhaust (67) 
CLOSED 
Reset Valve (70) CLOSED 
Release Button Valves (72, 74) 
CLOSED ("OUT" POSITION) 
Application Valve (94) 
CLOSED 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
CLOSED 
Release Valve (Pressure) (100) 
CLOSED 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release 
Valve Exhaust (105) 
CLOSED 
______________________________________ 
The final brake cylinder pressure will be approximately twenty percent 
higher than is obtained in a full service application. It should be 
appreciated that during the pneumatic initiated emergency braking 
application the application valve remains closed to facilitate a two-stage 
braking process. However, since a pneumatic initiated emergency triggers 
an electronic emergency except when there is a complete failure of the 
electronic system, the application valves will be opened by the 
controllers throughout the train due to the electronic emergency which 
essentially nullifies the effect of the pneumatic emergency. Only if there 
is a failure in the electronic braking system will the electronic 
pneumatic braking system of the present invention rely on the two-stage 
braking pressure build-up throughout the train to perform the emergency 
braking. 
During any pneumatic emergency braking application, the diverter valve in 
the emergency assuring valve 64 monitors the pilot line 104. If there is a 
pressure of 15 psig or greater at the time of the pneumatic emergency 
application, the first stage as described above will be nullified and the 
build-up will only take place through the choke. This may occur, for 
instance, when a service application is in process and the train breaks in 
two. If the pilot line should overcharge beyond the preset pressure in the 
regulating valve 98, the excess will exhaust to atmosphere via the 
regulating valve exhaust 99. The brake cylinder pressure will thus be 
limited and maintained by the setting of the regulating valve. 
During the pneumatic emergency braking application, and until the brake 
pipe pressure is restored, the emergency charge valve and the emergency 
assuring valve will remain open. The emergency charge valve connects the 
supply reservoir to the valve supply volume during a pneumatic emergency 
application to maintain adequate pressure in the valve supply volume and 
thus the pilot line which compensates for the brake pipe at atmospheric 
pressure. Once the brake pipe pressure is restored, the emergency assuring 
valve and the emergency charge valve will close, cutting off communication 
to the pilot line and the valve supply volume, respectfully. 
As may be observed from the above description, an emergency application may 
be obtained by electronic or pneumatic initiated paths of communication or 
both. The pneumatic emergency application backs up the electronic 
emergency application and assures that if there should be a catastrophic 
failure of the controllers throughout the train, an emergency braking 
application would still occur. That is, even if the electronic emergency 
braking application initiated at the head end unit did not work, actuation 
of the automatic brake valve to the emergency position or the opening of 
the conductor's valve could be used to stop the train in an emergency 
situation. Additionally, the electronic system backs up the pneumatic 
system because an electronic emergency is initiated once a pneumatic 
initiated emergency is detected. Thus, the failsafe condition that has 
been built into former and present day air brake freight equipment, 
including the ability to stop the train in the shortest possible time and 
distance automatically, is assured. 
RELEASE FROM EMERGENCY 
If the emergency braking application was initiated from the head end unit, 
the engineer must first move the automatic brake valve to the suppression 
position and then to the release position in order to release the brakes. 
The head end unit will then allow the engineer to disengage the emergency 
braking activation switch on the head end unit which signals the 
controller to reduce the train to a full service braking application. If 
the emergency was initiated by a break in the train or brake pipe, the 
automatic brake valve on the locomotive must be moved to the emergency 
position and then to the release position in order to re-set the system. 
If the emergency application was initiated due to manual operation of the 
conductor's valve, then the brake valve must be moved to the emergency 
position if it is not already there and then moved to the release position 
to reset the system including the head end unit and the locomotive brake 
valve equipment. Once the head end unit and locomotive equipment have been 
reset, each of the controllers will also be reset. The controller reset 
will be indicated by the brake cylinder pressure on each car reducing to a 
full service application value and, once this is achieved, the controllers 
will assume a lap condition. No matter which type of emergency application 
initiated the current brake condition, the final release must be made via 
the head end unit when the controller is in an all electronic train. The 
remainder of the emergency release is accomplished as described under 
service braking release. 
MANUAL RELEASE OF THE BRAKE APPLICATION 
If it is desired to manually release a brake application without the use of 
the controller, as in switching movements, either release button valves 72 
or 74 may be opened by manually pushing in the button. This action will 
direct the air pressure in the supply reservoir 32 through the release 
button valve(s) and into the cylinder release supply line 103 to the 
cylinder release valve 102 causing the pressure activated cylinder release 
valve 102 to close and the cylinder release valve exhaust 105 to open. 
This cuts off the connection between the pilot line 104 and the relay 
valve 66 and vents to atmosphere the air pressure in the pilot line 104 
between the cylinder release valve 102 and the relay valve 66. This line 
will exhaust rapidly from the cylinder release valve exhaust 105. As this 
section of the pilot line 104 loses air pressure, the relay valve 66 will 
close and the relay valve exhaust 67 will open, thereby causing the brake 
cylinder 40 pressure as developed by the relay valve 66 to exhaust at a 
rapid rate though the relay valve exhaust 67. Air pressure that was 
developed from the previous braking application will remain in the pilot 
line 104 between the cylinder release valve 102 and the application valve 
94 or the emergency assuring valve 64. The following chart provides a 
summary of the valve positions during the manual release of braking, 
assuming the braking was non-emergency. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) CLOSED 
Relay Valve Exhaust (67) 
OPEN 
Reset Valve (70) CLOSED 
Release Button Valves (72, 74) 
OPEN ("IN" POSITION) 
Application Valve (94) 
CLOSED 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
CLOSED 
Cylinder Release Valve (102) 
CLOSED 
Cylinder Release OPEN 
Valve Exhaust (105) 
______________________________________ 
The brakes on the car may be re-applied, if so desired, by closing the 
release button valve(s) by manually pulling the release button(s) "out" As 
this occurs, the cylinder release valve 102 will open and the cylinder 
release valve exhaust 105 will close, thus reconnecting the pilot line 104 
with the relay valve 66, causing the relay valve to open and to develop 
brake cylinder pressure. This feature will allow brake cylinder pressure 
to be applied or released a number of additional times so as to allow 
adjustment to brake rigging or facilitate replacement of brake shoes. 
If the release button valves 72 and 74 are manually actuated and left in 
the open or "in" position, the brake will remain released. During train 
make-up, and after the brake pipe pressure has increased to a 
predetermined pressure, the controller 34 will reset the release button 
valves automatically by applying pressure from the solenoid actuated reset 
valve 70 to each release button valve pilot port to close the valves 
button. The action as described above of applying air to open the release 
button valves will also occur each time the engineer brakes or releases 
the brakes when using the head end unit at the lead locomotive. This 
feature will insure brakes throughout the train are available in the event 
that a brake or brakes are released. This feature also conserves time 
during train make-up at an initial terminal or during switching movements 
especially because all of the buttons may be closed from the head end 
unit. 
Referring now to FIGS. 4 and 5, an alternative embodiment of the present 
invention is shown which includes a control valve 30A operated by an 
electronic controller 34A and adapted to be used on electronic trains 
(i.e., with a head end unit) as well as conventional trains (i.e., without 
a head end unit). If a head end unit is detected during train set-up, the 
universal electronic pneumatic control valve 30A and the electronic 
pneumatic controller 34A will charge the system, provide service and 
emergency braking applications, and service and emergency release 
application exactly like the electronic pneumatic control valve 30 and the 
electronic pneumatic controller 34. If no head end unit is detected during 
train set-up, the universal electronic pneumatic control valve 30A and the 
electronic pneumatic controller 34A on each car will only respond to 
physical air pressure reductions and increases in the brake pipe as 
commonly used in the present freight car pneumatic brake equipment. Where 
there is no head end unit, the controller 34A detects the amount of the 
pressure reduction and calculates the amount of brake cylinder pressure 
needed for braking. 
The universal electronic pneumatic control valve 34A used on trains without 
a head end unit provides an improvement in braking pressure buildup time. 
Even though there is no head end unit, when the first controller detects a 
reduction in pressure in the brake pipe indicating the desired braking of 
the train, the controller will cause the control valve 34A to assist in 
the propagation of this brake pipe reduction, as described below. Thus, 
the controller 34A reduces transmission time in the service braking 
application. Likewise, when the first controller detects an increase in 
pressure in the brake pipe indicating the desired release of braking of 
the train, the controller will cause the control valve 34A to propagate 
this brake pipe pressure increase by way of the brake pipe throughout the 
train. Thus, the controller and control valve reduce transmission time in 
the service release of braking application. However, in the conventional 
mode, only direct braking release is available, as opposed to graduated 
release. 
More specifically, the electronic pneumatic control valve 30A uses the 
service side manifold 44 of control valve 30 and replaces emergency side 
manifold 46 with manifold 46A (labeled "MANIFOLD-2A"). Manifold 46A has 
the same configuration as manifold 46, except that it includes a charge 
control check valve 58a (labeled "CHECK VALVE 2"), a solenoid actuated 
release assist valve 122, a solenoid actuated initial quick service valve 
124, and a solenoid actuated emergency magnet valve 126, all connected to 
the supply line 55. The release assist valve 122 connects the supply 
reservoir 32 to the brake pipe 24 via the reservoir supply line 65 and the 
supply line 55. The initial quick service valve 124 and the emergency 
magnet valve 126 each include an exhaust port for releasing air pressure 
in the supply line. The charge control check valve 58a differs from the 
check valve 58 in that it is a dual cartridge valve with an additional 
valve which is normally open and which may be actuated by a solenoid to 
reduce the charging rate of the supply reservoir in a conventional train 
or to cut off charging when a reduction of brake pipe pressure is 
detected. 
CHARGING 
To charge the system with the electronic pneumatic control valve 30A, the 
compressed air in the brake pipe 24 travels through the dirt 
collector/cut-out cock 28, into the pipe bracket 42, and is directed to 
the service and emergency sides of the pipe bracket. Air at the service 
side of the pipe bracket 42 travels into manifold 44 and to the vent valve 
52 which is closed and remains closed during normal operation, except as 
described below. Air at the emergency side of the pipe bracket 42 travels 
into manifold 46A, through manifold filter 54, into the supply line 55 and 
to emergency charge valve 56, charge control check valve 58a, check valve 
60, transducer 62, and emergency assuring valve 64, and the release 
control valve as in the embodiment of FIG. 3. The compressed air also 
travels through the supply line to the release assist valve 122, the 
initial quick service valve 124, and the emergency magnet valve 126. The 
release assist valve 122 is a normally closed conventional solenoid 
actuated valve which is closed during charging. Similarly, the initial 
quick service valve 124 and the emergency magnet valve 126 are normally 
closed conventional solenoid actuated valves which are closed during 
charging. These valves are available from Clippard Instrument Laboratory, 
Inc. 
The compressed air flows through open check valve 58a through reservoir 
supply line 65 to relay valve 66, emergency charge valve 56, transducer 
68, reset valve 70, release button valves 72 and 74, and to the supply 
reservoir via ports "e3", "2", "e2", "a", and "5". Additionally, air in 
the reservoir supply line 65 will be directed to the closed release assist 
valve 122. If no head end unit is detected by the controller 34A, the 
controller will reduce and modulate the charging rate of the supply 
reservoir through charge control check valve 58a to that of the present 
freight brake equipment so as to facilitate substantially equal charging 
of the systems in the train. The maximum pressure in the supply reservoir 
is equal to the maximum pressure carried in the brake pipe. The compressed 
air also flows through check valve 60 to the pilot supply line 90 and to 
the valve supply volume or chamber 92, the emergency charge valve 56, the 
application valve 94, the transducer 96, and the regulating valve 98. 
The electronic pneumatic valve 30A also includes a cylinder release valve 
102 attached to a pilot line 104. The transducer 108 monitors the pressure 
in the pilot line 104, the transducer 110 monitors the air pressure in the 
brake cylinder line 111 and brake cylinder pipe 38. The following chart 
provides a summary of the valves and their position during the charging of 
the universal electronic pneumatic control valve 30A. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Charge Control Check Valve 1 (58a) 
OPEN 
(modulated where no HEU) 
Check Valve 1A (60) 
OPEN 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) CLOSED 
Relay Valve Exhaust (67) 
OPEN 
Reset Valve (70) OPEN (MOMENTARILY) 
Release Button Valves (72, 74) 
CLOSED ("OUT" POSITION) 
Application Valve (94) 
CLOSED 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
OPEN 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release CLOSED 
Valve Exhaust (105) 
Release Assist Valve (122) 
CLOSED 
Initial Quick Service Valve (124) 
CLOSED 
Emergency Magnet Valve (126) 
CLOSED 
______________________________________ 
If there is a head end unit on the lead locomotive, then all applications 
on the electronic pneumatic control valve 30A are the same as on valve 30. 
If no head end unit is detected, the service, release, emergency, and 
emergency release applications are controlled pneumatically, as described 
below. 
SERVICE APPLICATION 
To initiate service braking, the engineer in the lead locomotive moves the 
automatic brake valve into the initial service zone to reduce the air 
pressure in the brake pipe. When a reduction of the air pressure in the 
brake pipe reaches the supply line 55, charge control check valve 58a and 
check valve 60 close, cutting off all charging of the supply reservoir 32 
and valve supply chamber 92. This reduction is detected by controller 34A, 
and controller 34A opens the initial quick service valve 124 to vent 
additional brake pipe pressure aiding in the reduction of the brake pipe 
pressure locally at the car, and serially propagating the reduction 
through the train. The controller 34A will calculate the level of pilot 
line pressure in relation to the amount of the brake pipe reduction as in 
controller 34, open the reset valve 70 momentarily, close the solenoid 
actuated valve of the release control valve 100, and open the application 
valve 94. As the pressure in the pilot line 104 increases, the relay valve 
66 will open and develop brake cylinder pressure equal to that of the 
pilot line, as described above. It should be appreciated that the 
controller 34A receives the pneumatic braking signal and calculates the 
brake cylinder pressure just like the controller 34 which receives an 
electronic braking signal. The following chart provides a summary of the 
valve positions during service braking. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Charge Control Check Valve 1 (58a) 
CLOSED 
Check Valve 1A (60) 
CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) OPEN 
Relay Valve Exhaust (67) 
CLOSED 
Reset Valve (70) OPENED (MOMENTARILY) 
Release Button Valves (72, 74) 
CLOSED ("OUT" POSITION) 
Application Valve (94) 
OPEN 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
CLOSED 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release CLOSED 
Valve Exhaust (105) 
Release Assist Valve (122) 
CLOSED 
Initial Quick Service Valve (124) 
OPEN 
Emergency Magnet Valve (126) 
CLOSED 
______________________________________ 
As the brake pipe reduction ceases and the pressure in the brake pipe 
levels out, the controller 34A will close the initial quick service valve 
124 to stop the further propagation of the reduction signal throughout the 
train. As the pressure in the brake cylinder 40 reaches the value in the 
pilot line 104, the relay valve 66 will cease increasing the brake 
cylinder pressure and assume a lap condition as in control valve 30. The 
controller 34A and the electronic pneumatic control valve 30A monitor the 
brake cylinder pressure to maintain the brakes, also as in control valve 
30. 
If additional braking force is desired, the engineer must again reduce the 
brake pipe pressure using the automatic brake valve. The propagation of 
this reduction using the initial quick service valve 124 as described 
above will be repeated in reference to the additional reduction up to a 
full service brake application in proportion to the maximum pressure 
carried in the brake pipe during charging. With each additional reduction, 
the controller will open the solenoid actuated initial quick service valve 
to provide an additional path of exhaust for brake pipe pressure to 
propagate the reduction back through the train. As stated above, all other 
aspects of the service braking application are the same as in valve 30. 
Likewise, the operation of the controller 34A is the same except that it 
also regulates the initial quick service valve 124. 
SERVICE RELEASE AND RELEASE ASSISTING 
To release the brakes in the embodiment of FIGS. 4 and 5, the engineer must 
increase air pressure in the brake pipe by moving the automatic brake 
valve to the release position. Release of the brakes will begin when the 
controller 34A detects an increase in brake pipe pressure via transducer 
62 wherein the brake pipe pressure is greater than the air pressure in the 
supply reservoir as measured by transducer 68. Once this differential is 
detected, the controller 34A will close the application valve 94, if it is 
not already closed, and open the solenoid actuated valve of the release 
control valve 100 to exhaust the pilot line 104 to the atmosphere which 
will actuate the relay valve 66 to close communication between the supply 
reservoir and the brake cylinder. The relay valve exhaust 67 will open to 
exhaust the air pressure in the brake cylinder line 111, and the brake 
cylinder pressure will be reduced as in the service release of control 
valve 30. 
When the controller 34A starts the release cycle by opening the release 
control valve 100, the controller will also open the release assist valve 
122 to back-dump air pressure in the supply reservoir to the brake pipe 24 
so as to assist in propagating the braking release signal back through the 
train. The following chart provides a summary of the valve positions 
during release of braking with the back-dumping of air pressure from the 
supply reservoir 32 to the brake pipe 24. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Charge Control Check Valve 1a (58a) 
CLOSED 
Check Valve 1A (60) CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) CLOSED 
Relay Valve Exhaust (67) 
OPEN 
Reset Valve (70) CLOSED 
Release Button Valves (72, 74) 
CLOSED (OUT) 
Application Valve (94) CLOSED 
Regulating Valve (98) OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
OPEN 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release CLOSED 
Valve Exhaust (105) 
Release Assist Valve (122) 
OPEN 
Initial Quick Service Valve (124) 
CLOSED 
Emergency Magnet Valve (126) 
CLOSED 
______________________________________ 
The release assist valve 122 will be closed once the brake pipe 24 and the 
supply reservoir 32 pressures equalize within approximately 10 psig or 
when the supply reservoir 32 pressure has reduced to approximately 50 
psig, whichever occurs first. When this occurs, the controller 34A will 
actuate the solenoid of charge control check valve 58a and partially 
reopen the charge control check valve 58a to recharge the supply reservoir 
32 at a reduced or retarded rate. When the supply reservoir 32 pressure 
stabilizes within approximately 5 psig of the brake pipe 24, the 
controller will fully reopen the charge control check valve 58a to charge 
the supply reservoir 32 at the normal rate. This reduced or retarded rate 
of charge is necessary to obtain a more uniform recharge throughout the 
train. Direct release, as opposed to graduated release, is the only type 
of release allowed when the controller 34A is in this mode because there 
is no head end unit. If at any time a brake system on a given car becomes 
defective or malfunctions, the controller on that car will cut out the 
affected brake system and log the fault in the memory of the controller 
for downloading by car department personnel at the next terminal. 
Likewise, other information can be loaded into the controllers for future 
use. 
EMERGENCY APPLICATION 
Where there is no head end unit, emergency brake applications are only 
available throughout the train at any time via pneumatic communication in 
the embodiment of FIGS. 4 and 5. A pneumatic emergency brake application 
and rapid reduction in brake pipe pressure may be initiated by a 
break-in-two of the train or of the brake pipe, by a burst hose at either 
end of the brake pipe on a given car, by the engineer moving the automatic 
brake valve to the emergency position venting pressure in the brake pipe, 
or by a crew member physically opening a conductor's valve, thereby 
venting the brake pipe to atmosphere. 
A rapid reduction of the brake pipe pressure will cause the vent valve 52 
to open venting the brake pipe to atmosphere and serially passing this 
action through the train. In addition, when the controller 34A detects the 
brake pipe pressure reducing at an emergency rate via transducer 62, the 
controller will open the emergency magnet valve 126 to further vent the 
supply line and the brake pipe pressure to the atmosphere. The emergency 
magnet valve 126 includes a timer which starts when the emergency magnet 
valve is opened and holds this valve open for ninety seconds. After ninety 
seconds, the emergency magnet valve resets itself and closes. As the brake 
pipe vents, the controller 34A will close the solenoid actuated valve of 
the release control valve 100. The significant drop in pressure in the 
brake pipe 24 will also cause the pressure actuated valve of the release 
control valve 100 to close, thus insuring that the release control valve 
is closed even if the controller malfunctions. The emergency rate pressure 
drop in the pilot supply line 90 will cause the emergency assuring valve 
to open, thereby connecting the air pressure from the supply reservoir 32 
to the pilot line 104, raising the pressure in the pilot line 104 in two 
stages as described above for the pneumatic emergency condition in control 
valve 30. The emergency rate drop in pressure will also cause the 
emergency charge valve 56 to open, thereby connecting the supply reservoir 
32 to the valve supply volume 92 to maintain adequate pressure in that 
volume and the pilot supply line. The first stage braking at approximately 
15 psig occurs in approximately one and one-half seconds and the remaining 
brake cylinder pressure build-up will occur in approximately four and 
one-half seconds through the choke 120. The brake cylinder pressure will 
be maintained at or below the setting of the regulating valve 98. The 
following chart provides a summary of the valve positions during the 
second stage of the pneumatic emergency brake pressure build-up. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) OPEN 
Emergency Charge Valve (56) 
OPEN 
Charge Control Check Valve 1a (58a) 
CLOSED 
Check Valve 1A (60) 
CLOSED 
Emergency Assuring Valve (64) 
OPEN ONLY TO THE CHOKE 
Relay Valve (66) OPEN 
Relay Valve Exhaust (67) 
CLOSED 
Reset Valve (70) CLOSED 
Release Button Valves (72, 74) 
CLOSED (OUT) 
Application Valve (94) 
CLOSED 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
CLOSED 
Release Control Valve (Pressure) 
CLOSED 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release CLOSED 
Valve Exhaust (105) 
Release Assist Valve (122) 
CLOSED 
Initial Quick Service Valve (124) 
CLOSED 
Emergency Magnet Valve (126) 
OPEN 
______________________________________ 
The final brake cylinder pressure will be at least approximately twenty 
percent higher than is available with a full service application and is 
dependent upon the initial charge carried in the brake pipe. In a 
pneumatic emergency, all of the vent valves 52 on the cars throughout the 
train will open to serially propagate the pneumatic emergency through the 
train. Until the brake pipe pressure is restored, the emergency assuring 
valve 64 and the emergency charge valve 56 will stay open. Once the brake 
pipe pressure is restored, the emergency assuring valve 64 and the 
emergency charge valve 56 will close, cutting off communication to the 
pilot line 104 and valve supply volume 92, respectfully. 
RELEASE FROM EMERGENCY 
After the ninety second period during which the emergency magnet valve 126 
is held open, the emergency magnet valve will automatically close. After 
this interval has elapsed, the engineer may start the emergency braking 
release. If the emergency was initiated by a break in the train or brake 
pipe, the automatic brake valve on the locomotive must be moved to the 
emergency position and then to the release position in order to reset the 
system. If the emergency application was initiated due to manual operation 
of the automatic brake valve or opening of the conductor's valve, then the 
automatic brake valve must be moved to the emergency position if it is not 
already there and then moved to the release position to reset the system. 
Obviously, if a conductor's valve was opened, it must be closed. As the 
brake pipe charges and the pressure reaches approximately 20 psig, the 
controller 34A will open the release assist valve 122 to back dump air in 
the supply reservoir 32 to the brake pipe 24. As the brake pipe pressure 
increases to within approximately 10 psig of the supply reservoir or the 
supply reservoir pressure has reduced to approximately 50 psig, whichever 
occurs first, the controller 34A will close the release assist valve 122. 
The final release of the brakes is accomplished as described above for 
service release. A manual release of the brake may also be accomplished 
using the release button valves 72 and 74 on the control valve 30A as 
described above for control valve 30. 
Referring now to FIGS. 2 and 6, an alternative embodiment of the present 
invention is shown which includes a control valve 30B operated by 
controller 34 and adapted to be used on the center car of a three-pack or 
five-pack articulated car set in electronic trains with a head end unit. 
The electronic pneumatic control valve 30B employs the emergency side 
manifold 46 (labeled "MANIFOLD-1A") of control valve 30 and differs from 
valve 30 in that the service side includes manifold 44B (labeled 
"MANIFOLD-2B"). Manifold 44B has a similar configuration as manifold 44, 
except that it includes a second relay valve 130 (labeled "#2 RELAY 
VALVE"). 
The operation of control valve 30B is identical to that of control valve 30 
except with respect to the operation of second relay valve 130. During 
charging, air in the reservoir supply line 65 is also connected to the 
secondary relay valve 130. During charging, the secondary relay valve is 
closed and the relay valve exhaust 131 is open. During service or 
emergency braking applications, the controller 34 opens the application 
valve 94 and/or the emergency assuring valve 64 directing air pressure 
into the pilot line 104 increasing the pressure in the pilot line 104 
calculated by the controller 34. This pressure build-up in the pilot line 
104 is directed through the cylinder release valve 102, and into the 
secondary pilot line 132. The pressure in the secondary pilot line 132 
travels through the flange fitting at port 134 (labeled "C3") into the 
pipe bracket 42 and through the flange fitting at port 136 (labeled "C4") 
into manifold 44B. The pressure is directed in manifold 44B through the 
secondary pilot line 132 to the secondary relay valve 130. The secondary 
relay valve 130 will mimic the actions of the relay valve 66. Accordingly, 
the secondary relay valve 130 opens to connect the supply reservoir 32 to 
a relay line 138 in the manifold 44B that connects through a flange 
fitting at port 140 in the pipe bracket to a relay pipe 142 through a 
secondary cutout cock 144. The secondary pilot line 132, relay line 138, 
and relay pipe may be of small diameter to allow quick buildup of the 
pressure in these lines. The relay pipe 142 is connected to the other 
articulated cars in the three-pack or five-pack set to communicate braking 
and release signals to the braking unit of the additional cars, as shown 
in FIG. 7 and described below. The following chart provides a summary of 
the valve positions for the electronic control valve 30B during the 
service braking in a three-pack or five-pack articulated car set. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Emergency Charge Valve (56) 
CLOSED 
Emergency Assuring Valve (64) 
CLOSED 
Relay Valve (66) OPEN 
Relay Valve Exhaust (67) 
CLOSED 
Reset Valve (70) OPENED (TEMPORARILY) 
Release Button Valves (72, 74) 
CLOSED (OUT) 
Application Valve (94) 
OPEN 
Regulating Valve (98) 
OPEN 
Regulating Valve Exhaust (99) 
CLOSED 
Release Control Valve (100) 
CLOSED 
Cylinder Release Valve (102) 
OPEN 
Cylinder Release CLOSED 
Valve Exhaust (105) 
Secondary Relay Valve (130) 
OPEN 
Secondary Relay CLOSED 
Valve Exhaust (131) 
______________________________________ 
Referring now to FIG. 7, a pneumatic braking unit (i.e., a non-electronic 
pneumatic control valve), generally indicated by numeral 150, is mounted 
on each of the additional cars on a three-pack or five-pack articulated 
car set for use in conjunction with the electronic pneumatic control valve 
30B of FIG. 6 on the center car of a three-pack or five-pack articulated 
car set. The braking unit 150 generally includes a relay manifold 152 
(labeled "MANIFOLD-3B") attached to the service side of the pipe bracket 
and a blanking plate 154 (labeled "BLANKING PLATE-1") attached to the 
emergency side of the pipe bracket 42 to block all ports on that side 
except for connecting ports 112 and 134. 
During charging of the system on these articulated cars, the compressed air 
in the brake pipe 24 is directed through the dirt collector/cut-out cock 
28 and into the pipe bracket 42 and to the manifold 152 where the air is 
directed to the vent valve 52 and a check valve 156 (labeled "CHECK 
VALVE"). During charging, the vent valve 52 is closed and it remains 
closed during operation, except as described below. Check valve 156 is a 
normally closed conventional spring biased pressure actuated valve that 
opens when the pressure on the brake pipe side exceeds the pressure on the 
reservoir side. The compressed air flows through the check valve 156 to a 
secondary reservoir supply line or passageway 158 which is connected to a 
relay valve 160 (labeled "#3 RELAY VALVE") in manifold 152 and to both the 
emergency reservoir 80 and the auxiliary reservoir 88 which are combined 
as the supply reservoir 32. Air in the reservoir supply line 158 is 
thereby directed to the supply reservoir 32 and to the secondary relay 
valve 130 in the manifold 152 during charging and normal operation. The 
supply reservoir 32 provides compressed air to the relay valve 160 via the 
reservoir supply line 158 for use in applying the brakes, as described 
below. The blanking plate 154 renders redundant the valve supply chamber 
92. During charging, the relay valve 160 is closed and the relay valve 
exhaust 161 is open, which allows the brake cylinder pipe 38 to vent to 
atmosphere. The following chart provides a summary of the valve positions 
during charging of the relay control valve 150. 
______________________________________ 
VALVE POSITION 
______________________________________ 
Vent Valve (52) CLOSED 
Check Valve (156) OPEN 
Relay Valve (160) CLOSED 
Relay Valve Exhaust (161) 
OPEN 
______________________________________ 
The control valve 30B of FIG. 6 actuates the braking systems on the cars on 
either end of the pack. During service and emergency braking applications, 
the secondary relay valve 130 in control valve 30B on the center car opens 
to increase the pressure in the relay pipe 142. This increase in pressure 
signal travels to the additional cars on the articulated car set, through 
a cut-out cock 162 into the pipe bracket 42, and through relay pilot line 
164 to the relay valve 160 which mimics the actions of the relay valve 66, 
as well as the secondary relay valve 130, in control valve 30B. As the 
pressure to the relay valve 160 increases, the relay valve 160 opens, 
thereby directing air pressure from the supply reservoir 32 through the 
relay valve 160 and to the relay brake cylinder line 166. The brake 
cylinder line 166 directs the air pressure through the manifold 152 to the 
pipe bracket 42 at port 136 (labeled "C4"), through the pipe bracket to 
port 134 (labeled "C3"), and into the blanking plate 154. The blanking 
plate 154 directs the air back through the pipe bracket at port 112 
(labeled "C") through port 114 (labeled "PORT 3") to the brake cylinder 
pipe 38 and to the brake cylinder 40 to apply the brakes on the additional 
car. 
The additional relay valve 160 will direct air pressure from the supply 
reservoir 32 to the brake cylinder 40 to apply braking on additional cars 
in the three-pack or five-pack articulated car set at substantially the 
same time as the relay valve 66 on the center car directs air pressure to 
the brake cylinder line on that car. Since the secondary relay valve 130 
on the center car and the additional relay valve 160 on the additional 
cars mimic the relay valve 66 on center car, the braking operations on all 
cars in the pack will respond alike during service braking, service 
release, emergency braking, emergency release applications, and manual 
braking release. 
Referring now to FIGS. 4 and 8, a further embodiment of the present 
invention is shown which includes a universal electronic pneumatic control 
valve 30C operated by the controller 34A for use on three-pack or 
five-pack articulated car sets. Being universal, this control valve will 
work on electronic trains having a head end unit as well as trains without 
a head end unit to provide electronically or pneumatically controlled 
braking. Further, this valve would be teamed with braking units on 
additional articulated cars like in FIG. 7. The control valve 30C includes 
the emergency side manifold 46A (labeled "MANIFOLD-2A") of control valve 
30A (FIG. 5) and the service side manifold 44B (FIG. 6) (labeled 
"MANIFOLD-2B") of control valve 30B. Thus, the electronic pneumatic 
control valve 30C will function like control valve 30A in trains having or 
not having a head end unit and will function like control valve 30B in 
regard to relaying braking signals to the additional cars in the 
three-pack or five-pack articulated car set. 
Referring now to FIGS. 9 and 10, a modification and a preferred embodiment 
of the present invention is shown which includes an electronic pneumatic 
control valve 30D operated by an electronic pneumatic controller 34D, in 
combination with a head end unit on a locomotive. The control valve 30D 
employs the service side manifold 44 (labeled "MANIFOLD-1B") of control 
valve 30 and replaces the emergency side manifold 46 with a manifold 46D 
(labeled "MANIFOLD-1A-1"). 
Control valve 30D is like control valve 30, except that it is simpler and 
less expensive because it incorporates the function of the emergency 
charge valve into the emergency assuring valve 64A and eliminates the 
transducer T4 which measures the pressure in the pilot line 104. 
Similarly, the controller 34D is like controller 34, except that it does 
not monitor transducer T4 and it monitors a pressure switch 202 in the 
control valve 30D for shutting down the controller when the car is not in 
use, as discussed below. More particularly, the emergency assuring valve 
64A includes a pair of normally open spring-biased pressure actuated 
valves, which are maintained closed by the air pressure in the braking 
pipe 24 and the supply line 55 during charging, service applications, 
release applications, electronic emergency braking applications, and 
emergency releases. However, during pneumatic emergency braking 
applications, the pressure in the brake pipe 24 drops at an emergency rate 
and below a threshold level, causing a drop in pressure from the supply 
line 55 to the emergency assuring valve 64A. The pressure drop causes the 
valves in the emergency assuring valve to open, connecting the supply 
reservoir 32 via the supply reservoir line 65 to the valve supply chamber 
92 via the pilot supply line 90. The opening of this valve eliminates the 
need for the emergency charge valve because it allows the supply reservoir 
to constantly recharge the valve supply chamber during pneumatic emergency 
braking applications. The drop in pressure also causes the other valve in 
the emergency assuring valve 64A to open, connecting the valve supply 
chamber 92 via the pilot supply line 90 and through the regulating valve 
98 to the pilot line 104 via a diverter valve 200. The diverter valve 200 
provides the two-stage braking necessary for pneumatic emergencies and is 
a conventional spring-biased pressure actuated valve which is normally 
open to the pilot line. The diverter valve 200 directs the air pressure 
from the valve supply chamber directly to the pilot line 104 for 
approximately one and one-half seconds to provide the first stage of 
braking. When the diverter valve, which is actuated by a changing pressure 
in the pilot line, senses approximately 15 psig in the pilot line 104, it 
will divert the air pressure from the valve supply chamber 92 through the 
choke 120. The choke facilitates the second stage of pressure build-up in 
the pilot line 104 in approximately four and one-half seconds, thereby 
retarding the brake pressure buildup. The increase of pressure in the 
pilot line 104 causes the relay valve 66 to open, connecting the supply 
reservoir 32 to the brake cylinder 40. 
The pressure switch 202 minimizes drain on the battery or power supply 48 
which provides power to the controller 34D, and is connected to and 
monitors the supply line 55. The pressure switch includes a timer 
activated at substantially zero pressure in the supply line or brake pipe. 
After a predetermined period of time, such as twenty to thirty minutes, 
the timer in the pressure switch turns off the central processing unit 47 
of electronic controller 34D to stop battery drain. Alternatively, the 
pressure switch 202 could be connected between the power supply 48 and the 
central processing unit 47 to cut the power between them, thereby shutting 
down the central processing unit. When the pressure in the brake pipe and 
thus the supply line resumes (i.e., when the car is hooked up to a train), 
the pressure switch 202 is actuated to turn on the electronic controller 
34D. 
The control valve 30D further includes a valve supply drain 204 manually 
operable for exhausting the valve supply chamber 92 in the pipe bracket. 
The valve supply drain 204 is a pressure closable and manually openable 
and closable valve which facilitates the emptying of the valve supply 
volume, for instance, when a car is disconnected from a train. The valve 
supply drain is connected to the valve supply chamber 92 via the pilot 
supply line 90 and is also connected to the reset valve 70. Each time the 
reset valve 70 is opened during service braking and emergency braking to 
insure that the release button valves 72 and 74 are closed, the reset 
valve also directs air pressure to the valve supply drain 204 to insure 
that it is closed. Additionally, during charging of the system, when there 
are approximately 20 psig in the supply reservoir 32, the controller 34D 
will open the reset valve 70 to insure that the valve supply drain is 
closed. After the reset valve is temporarily opened, the air directed to 
the release button valves 72 and 74 and the valve supply drain 204 will be 
exhausted through the reset valve exhaust 71. 
While transducers 62 ("T1"), 68 ("T2"), 96 ("T3"), and 110 ("T5") are 
employed in control valve 30D, transducer T4 employed in the control valve 
30 to measure the air pressure in the pilot line 104 is omitted from 
control valve 30D because it is not needed. The controller 34D may be 
programmed such that it does not need direct information on the pressure 
in the pilot line 104 because the controller receives information 
regarding the pressure in the brake cylinder line 111, brake cylinder pipe 
38, and brake cylinder 40, from transducer T5. The air pressure in the 
brake cylinder line 111 is equal to the pressure in the pilot line 104 
since the relay valve 66 directs air pressure to the brake cylinder from 
the supply reservoir 32 at a pressure equal to that of the pilot line 104. 
Thus, if the pressure to the brake cylinder 40 drops because of leakage or 
otherwise during service applications, the controller 34D will reopen the 
application valve 94 to increase the pressure in the pilot line 104 and 
thus the brake cylinder line 111 via the opening of the relay valve 66. 
Likewise, if the brake cylinder pressure is greater than the desired 
pressure, for instance, in a graduated release, the controller will open 
the release control valve 100 to drop the pressure in the pilot line 104, 
thereby causing the relay valve to operate to exhaust brake cylinder 
pressure through the relay valve exhaust 67 down to the desired braking 
level. Accordingly, the controller 34D and the control valve 30D may work 
without directly receiving information as to the pressure in the pilot 
line 104. All other functions of the controller 34D and control valve 30D 
are the same as controller 34 and control valve 30, including vent valve 
52, check valves 58 and 60, and cylinder release valve 102. 
The electronic pneumatic brake system of the present invention may also 
include a drain cock 210 for facilitating manually draining of the supply 
reservoir 32, for instance, when a car is disconnected from a train. The 
drain cock 210 is a manually operated valve which may be connected to the 
pipe between the control valve and the supply reservoir, and in particular 
the auxiliary reservoir, although it should be appreciated that it may be 
connected to the emergency reservoir, or both. 
Referring now to FIGS. 11 and 12, a modification and preferred embodiment 
of the present invention is shown which includes a universal electronic 
pneumatic control valve 30E operated by an electronic pneumatic controller 
34E and adapted to be used on a train with or without a head end unit in 
the locomotive. The control valve 30E employs the service side manifold 44 
(labeled "MANIFOLD-1B") of control valve 30 and replaces the emergency 
side manifold 46 with manifold 46E (labeled "MANIFOLD-2A-1"). Control 
valve 30E operates and functions exactly as control valve 30D when used on 
a train with a head end unit. If there is no head end unit on the train, 
the control valve 30E and the controller 34E respond to pneumatic brake 
signals in the brake pipe 24 issued by the engineer using the automatic 
brake valve. 
Similar to control valve 30D, control valve 30E incorporates the function 
of the emergency charge valve into the emergency assuring valve 64A, 
includes a diverter valve 200, a pressure switch 202, and a valve supply 
drain 204 and eliminates transducer T4. The control valve 30D further 
includes an initial quick service valve 124 connected to the supply line 
55 which assists in propagating the brake pipe pressure reduction during 
service applications similar to control valve 30A. More particularly, when 
the controller 34E senses a reduction in the brake pipe, it will actuate 
or open the solenoid operated initial quick service valve 124 to reduce 
the pressure in the supply line 55, and thus the brake pipe 24 which 
propagates the braking signal back through the train. The controller 34E 
will close the initial quick service valve when it senses the reduction of 
air pressure in the brake pipe leveling off at a reduced pressure through 
transducer 62. 
The control valve 30E further includes two solenoid actuated release assist 
valves 122A and 122B which connect the supply reservoir 32 via the supply 
reservoir line 65 to the brake pipe 24 via the supply line 55 to 
facilitate back dumping of air to the brake pipe from the supply reservoir 
during release applications for propagating the pneumatic brake signal to 
other cars. The release assist valves 122A and 122B are normally closed 
solenoid actuated valves which function like the release assist valve 122 
in control valve 30A. Two release assist valves are preferable to insure 
that enough air pressure flow is directed from the supply reservoir to the 
brake pipe during the back dumping procedure. The controller 34E opens 
these valves when it senses an increase in the brake pipe pressure which 
indicates a release of braking. When the controller senses the pressure in 
the brake pipe leveling off, it will close the release assist valves 122A 
and 122B. It should be appreciated that the release assist valves could be 
configured to be piloted or controlled by a single solenoid operated by 
the controller. 
The control valve 30E also includes a charge control check valve 58a 
(labeled "CHECK VALVE 2") like in control valve 30A. After the release 
assist valves 122A and 122B are closed (i.e., the brake pipe 24 and the 
supply reservoir 32 pressures equalize within approximately 10 psig or 
when the supply reservoir 32 pressure has reduced to approximately 50 
psig, whichever occurs first), the controller 34E will actuate the 
solenoid of charge control check valve 58a and partially reopen the charge 
control check valve 58a to recharge the supply reservoir 32 at a reduced 
or retarded rate. When the supply reservoir 32 pressure stabilizes within 
approximately 5 psig of the brake pipe 24, the controller will fully 
reopen the charge control check valve 58a to charge the supply reservoir 
32 at the normal rate. This reduced or retarded rate of charge is 
necessary to obtain a more uniform recharge throughout the train. Direct 
release, as opposed to graduated release, is the only type of release 
allowed when the controller 34E is in this mode because there is no head 
end unit. 
Referring now to FIGS. 9 and 13, a modification and a preferred embodiment 
of the present invention is shown which includes an electronic pneumatic 
control valve 30F operated by an electronic pneumatic controller 34D on 
the center car of a three-pack or five-pack articulated car set in a train 
with a head end unit. The control valve 30F employs the emergency side 
manifold 46D (labeled "MANIFOLD-1A-1") of control valve 30D, as shown in 
FIG. 10, and replaces the service side manifold 44 with a manifold 44B 
(labeled "MANIFOLD-2B"), as in control valve 30B in FIG. 6. 
The control valve 30F is like control valve 30D of FIG. 10 except that it 
additionally directs pressure in the pilot line 104 into a secondary pilot 
line 132. The pressure in the secondary pilot line is directed through the 
pipe bracket 42 and to the secondary relay valve 130 in the manifold 44B. 
The secondary relay valve directs air pressure from the supply reservoir 
32 to the relay pipe 142 in response to the pressure increase in the 
secondary pilot line 132, and thereby mimics the actions of relay valve 
66. The relay pipe directs this pressure increase to the additional or 
slave cars on the three-pack or five-pack articulated car set like control 
valve 30B of FIG. 6. 
Referring now to FIG. 14, a modification and a preferred embodiment of the 
present invention is shown which includes a non-electronic pneumatic brake 
unit 150A for the additional or slave cars in a three-pack or five-pack 
articulated car set. Braking unit 150A responds to pressure increases and 
decreases in the relay pipe 142. The brake unit 150A is exactly like brake 
unit 150 (FIG. 7) except that it includes a service side manifold 152A 
(labeled "MANIFOLD-3B-2") which does not include a vent valve while 
blanking plate 154A includes a vent valve 52a. The vent valve in this 
embodiment which is connected to the brake pipe 24 has been moved to the 
blanking plate because it may be difficult to physically fit the vent 
valve on manifold 152A. Otherwise, braking unit 150A functions exactly as 
braking unit 150 in charging the supply reservoir 32 and 17 applying the 
brakes on the additional cars in an articulated car set in response to 
pneumatic signals relayed from the center car through the relay pipe 142. 
It should therefore be appreciated that that braking unit 150A may be 
installed on the additional cars of a three-pack or five-pack articulated 
car set in conjunction with the control valve 30B and controller 34, or 
control valve 30C and controller 34A, as well as with control valve 30F 
and controller 34D. 
Referring now to FIGS. 11 and 15, a modification and a preferred embodiment 
of the present invention is shown which includes a universal electronic 
control valve 30G operated by an electronic pneumatic controller 34E and 
adapted to be used on the center car of a three-pack or five-pack 
articulated car set in a train having or not having a head end unit. The 
control valve 30G employs the service side manifold 44B (labeled 
"MANIFOLD-2B") of control valve 30B (FIG. 6) and control valve 30F (FIG. 
13) and employs the emergency side manifold 46E (labeled "MANIFOLD-2A-1") 
of control valve 30E (FIG. 12). Control valve 30G functions exactly like 
control valve 30E whether or not there is a head end unit and thus 
responds to pneumatic braking signals when there is no head end unit. It 
additionally functions like control valve 30F in that it relays a 
pneumatic braking signal to the additional cars in an articulated car set 
via the relay pipe 142. The universal control valve 30G and controller 34E 
thus work in conjunction with the braking unit 150A (FIG. 14) to apply the 
brakes on an articulated car set. 
It will be understood that modifications and variations may be effected 
without departing from the scope of the novel concepts of the present 
invention, and it is understood that this application is to be limited 
only by the scope of the appended claims.