Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02243799 1998-07-24
26-TYPE ELECTRONIC CONTROLLED PNEUMATICS
FIELD OF THE INVENTION
The present invention relates, in general, to railway
vehicle brake equipment and, more particularly, the invention
is directed to a system which allows for electronic control
of an air braking system in a train and is, still more
particularly, applicable for the 26-Type braking systems.
BACKGROUND OF THE INVENTION
A "26-L" air brake system is an equipment package which
has been designed to meet present day train handling
requirements. This system uses air, under pressure, for the
braking of locomotives and trailing freight or passenger
vehicles. This system has been designed and developed by the
Westinghouse Airbrake Company (WABCO), the assignees of the
present invention.
A "26-L" system can include either a "26-C" air brake
control valve or a "26-F" air brake control valve as the
primary controlling device in this equipment arrangement.
These valves provide the manual means for initiating air
brake application and releases.
The "26-C" valve is used for passenger locomotives and
cars. The "26-F" valve is used for freight locomotives and
cars. The present invention can be applied to either the "26-
C" or the "26-F" system and thus the term 26-Type is meant to
encompass either of these braking systems.
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The 26-Type braking system relies on the transfer of air
down the train, which propagates at a certain time frame, to
achieve stopping of the train. This type of braking system
has several disadvantages. One disadvantage of this system
is the requirement of the train to have a long enough
stopping distance to compensate for the time it takes for the
air to be transferred down the train. Also, care must be
taken to ensure that the air supply has been sufficiently
replenished after a brake application or a series of brake
applications prior to another brake application.
Additionally, this currently used 26-Type braking system is
limited in the number of units, approximately fifteen cars in
the area of passenger transport, that may be placed within a
train consist because of the system's inability to react
quickly to reductions at the lead unit over long distances.
The present invention will allow for electronic
controlled pneumatics of the 26-Type braking system which
will overcome the aforementioned disadvantages of the
currently used 26-Type braking systems resulting in an
improvement of the safety of the braking system as well as
providing significant economic advantages.
SUN~IARY OF THE INVENTION
The object of the present invention is to provide a
system for electronically controlling the pneumatics of an
air braking system for a train and particularly for the 26-
Type braking systems currently being used. Such electronic
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control would provide the advantages of shorter stopping
distances, a replenishable air supply source, enhanced
trainline communication features, and an unlimited number of
units which may be placed in the train consist.
This system for electronically controlling the
pneumatics of 26-Type braking systems comprises a tramline
or intratrain communication means for sending brake
application and/or brake release communications down the
train and junction boxes which are located at each end of
each of the cars within the consist which receive these
communications from the communication line. The junction
boxes convert these communication signals to an acceptable
input level so that they may be fed to the ECP (electronic
controlled pneumatic) car control unit. The ECP car control
unit may also be referred to as the central control unit.
This unit holds the software for controlling the pneumatic
unit and many electronics transfer features for the system.
The pneumatic unit contains electropneumatic and pneumatic
valves which react to the brake application and/or brake
release electronic signals sent from the ECP car control
unit and deliver the final input pressure to the car brake
cylinders accordingly.
The present invention may be applied to either a
standard braking system or to a relayed system.
This system also has the safeguard that in the event of
an electronic system failure, the 26 control valve can take
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over and braking capabilities for the train will still be
available.
Further features and advantages will become apparent
from the following detailed description taken in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows an overview of an intratrain
communication system for the movement of information
throughout a train consist.
Figure 2 shows a single car within a train consist
including the individual components for electronically
controlling the air brake cylinders of the car.
DETAILED DESCRIPTION OF THE INVENTION
Figure 1 shows an intratrain communication system for
the movement of information throughout a train consist 10
comprising a locomotive 11 having a locomotive brake control
valve 13 and a plurality of cars 12, at least one of which
includes an electronic controlled pneumatic (ECP) car control
unit 14. The locomotive brake control valve 13 feeds
communication signals to the car brake control unit 14 via an
intratrain communication system 15. This intratrain
communication system communicates information, such as a
brake application or brake release command, via radio or
electric current signals or any well known communicating
means.
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Figure 2 shows a single car 12 within a train consist 10
including the individual components for electronically
controlling the air brake cylinders of the car. Typically
each car within the train consist will include these
components, however, this system may be designed such that
these components would not be required on every car. This
may be the case, for example, on cars which are connected
together in a semi-permanent manner and would only be
disconnected for repairs. The car 12 includes trainline or
intratrain communication means 15 for transmitting at least
brake application and/or brake release communications down
the train. Note that other types of communications may be
transmitted along this intratrain communication means.
Junction boxes 20 are located at each end of the car 12 to
receive at least these brake application and/or brake release
communications from the intratrain communication line 15 and
to convert these communication signals to an acceptable input
level, such as by dropping the voltage level, so that they
may be fed to the ECP (electronic controlled pneumatic) car
control unit 14. The ECP car control unit 14 may also be
referred to as the central control unit. This unit holds the
software for controlling the pneumatic unit 17, as well as
many electronics transfer features for the system. The
pneumatic unit 17 contains electropneumatic and pneumatic
valves which react to the electronic signals sent from the
ECP car control unit 14 and delivers the final input pressure
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via the brake pipe 18 to the car brake cylinders, based upon
this signal.
The present invention may be applied to either a
standard braking system or to a relayed system. A relayed
system requires the provision of a relay valve 19, such as a
J-Relay valve, to discharge the output pressure from the
pneumatic valve and to deliver the final input pressure to
the brake cylinders, whereas in a standard system, the output
pressure is fed directly from the pneumatic valve. A relayed
system is used when longer cars are used in the train.
This system is such that one can monitor the brake pipe
and the 16 line or deliver pressure with the pneumatic unit.
The Control reservoir and the Auxiliary reservoir are the
supply sources available to make a brake application. A
brake application is accomplished by first isolating the 26-
Type control valve, keeping this valve in the release
position, (which provides a continuous recharging feature),
and allowing the electronic controlled pneumatics to take
over the brake applications. This system also has the
safeguard that in the event of an electronic system failure,
the 26 control valve can take over and braking capabilities
for the train will still be available.
The present invention has significant advantages over
the previously used 26-Type braking systems which rely on the
transfer of air down the train, which propagates at a certain
time frame, to achieve stopping of the train. The electronic
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controlled pneumatics of the present invention allows for an
almost instantaneous application of the brakes to all of the
units in the train consist, thus reducing stopping distances.
The 26-Electronic Controlled Pneumatics system also creates a
replenishable supply source of air since the transfer medium
is through the electronics and not the pneumatics. Another
advantage of the present invention is that it allows for
tramline or intratrain communication features to be built
into the system. Additionally, the present invention is not
limited in the number of units which may be placed within a
train consist. This capability has significant economic
advantages.
Thus, the present invention has been described in such
full, clear, concise and exact terms as to enable any person
skilled in the art to which it pertains to make and use the
same. While the present invention has been described in
relation to its use on a passenger car, note that this system
is not limited to this use and may be applicable to other
types of cars within a train consist. It will be understood
that variations, modifications, equivalents and substitutions
for components of the specifically described embodiments of
the invention may be made by those skilled in the art without
departing from the spirit and scope of the invention as set
forth in the appended claims.
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