U.S. patent application number 13/497858 was filed with the patent office on 2012-08-02 for brake system having smart actuator for braking a rail-guided vehicle.
This patent application is currently assigned to SIEMENS AG. Invention is credited to Toni Schiffers, Manfred Wiesand.
Application Number | 20120192757 13/497858 |
Document ID | / |
Family ID | 43603539 |
Filed Date | 2012-08-02 |
United States Patent
Application |
20120192757 |
Kind Code |
A1 |
Schiffers; Toni ; et
al. |
August 2, 2012 |
BRAKE SYSTEM HAVING SMART ACTUATOR FOR BRAKING A RAIL-GUIDED
VEHICLE
Abstract
A brake system for braking a rail vehicle has an actuator, which
is equipped for installation in its totality in a bogie of the rail
vehicle and provided with a braking force F so as to create a
braking movement of at least one pressing part, and an energy
storage device which is connected to the actuator via a supply
line. A brake controller supplies control signals for controlling
the brake system, which enables secure braking of the rail vehicle.
The actuator has a control connection, which is connected to the
brake controller for receiving the control signals via a data line,
wherein the control connection is connected to a logic unit of the
actuator that is configured to set the braking force F in
dependence on the control signals.
Inventors: |
Schiffers; Toni; (Erkelenz,
DE) ; Wiesand; Manfred; (Burgthann, DE) |
Assignee: |
SIEMENS AG
MUNICH
DE
|
Family ID: |
43603539 |
Appl. No.: |
13/497858 |
Filed: |
August 23, 2010 |
PCT Filed: |
August 23, 2010 |
PCT NO: |
PCT/EP2010/062232 |
371 Date: |
April 12, 2012 |
Current U.S.
Class: |
105/1.4 ;
188/153R; 188/158; 701/19 |
Current CPC
Class: |
B60T 13/665 20130101;
B60T 8/3235 20130101; B60T 17/228 20130101 |
Class at
Publication: |
105/1.4 ; 701/19;
188/158; 188/153.R |
International
Class: |
B61H 13/00 20060101
B61H013/00; B61D 17/00 20060101 B61D017/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 23, 2009 |
DE |
10 2009 042 965.4 |
Claims
1-20. (canceled)
21. An actuator for a brake system of a rail vehicle, the actuator
comprising: means for generating a braking force for at least one
pressing part receiving the braking force; a supply connection for
connecting the actuator to an energy storage unit, wherein the
actuator is configured in its entirety for mounting in a bogie of
the rail vehicle; a control connection for connecting to a data
line; and a logic unit connected to said control connection and
configured to set the braking force in dependence on a control
signal transferred over the data line.
22. The actuator according to claim 21, further comprising a
braking force detection unit for detecting a measured variable from
which a generated braking force can be derived as an actual value,
said braking force detection unit is connected to said logic
unit.
23. The actuator according to claim 21, wherein said supply
connection is an electrical supply connection which can be
connected to an electrical energy supply line and has output
terminals at which a supply voltage drops when the actuator
operates.
24. The actuator according to claim 23, wherein said means for
generating the braking force has an electromechanical force unit
connected to said supply connection and configured to generate a
mechanical triggering force in dependence on electrical energy
which is made available via said supply connection.
25. The actuator according to claim 24, wherein said
electromechanical force unit is selected from the group consisting
of an electric motor, an electric pump and a piezoelement.
26. The actuator according to claim 21, wherein said means for
generating the braking force is self-energizing.
27. The actuator according to claim 21, further comprising: an
electrically drivable emergency triggering means for releasing a
brake; and connecting means, electrically connected to said
emergency triggering means, for connecting to an external
electrical energy supply.
28. A brake system for braking a rail vehicle, the brake system
comprising: at least one pressing part; an actuator configured for
mounting in a bogie of the rail vehicle and configured to generate
a braking movement of said at least one pressing part with a
braking force; an electric supply line; an energy store connected
to said actuator via said electric supply line; a brake controller
for making available control signals and performing open-loop or
closed-loop control of the brake system; a data line; and said
actuator having a logic unit and a control connection connected to
said brake controller via said data line for receiving the control
signals, said control connection connected to said logic unit
configured to set the braking force in dependence on the control
signals, said actuator having means for generating the braking
movement for at least one pressing part with the braking force,
said actuator further having a supply connection for connecting
said actuator to said energy storage unit, wherein said actuator is
configured in its entirety for mounting in the bogie of the rail
vehicle.
29. The brake system according to claim 28, wherein said energy
store is an electrical energy store making available an electrical
supply voltage on an output side.
30. The brake system according to claim 28, further comprising a
converter unit connected to said brake controller and said
actuator, said converter unit having at least one converter which
makes available an electrical variable on an output side in
dependence on a signal for a load state which is fed in on an input
side, wherein said converter is configured for connection to at
least one of a pneumatic air spring of the rail vehicle or at least
one pneumatic line of the rail vehicle.
31. The brake system according to claim 30, wherein said converter
unit is connected to said energy store via said electrical supply
line.
32. The brake system according to claim 28, wherein said data line
is a data bus which connects said brake controller, said actuator
and said converter unit to one another.
33. The brake system according to claim 28, further comprising an
electrical safety loop, said actuator is one of a plurality of
actuators connected to one another via said electrical safety loop
configured to transmit control signals.
34. The brake system according to claim 28, further comprising
means for detecting at least one of a load state or a mass of the
rail vehicle and connected to said actuator, said actuator limits,
in dependence on the load state or the mass, the braking force to
be set.
35. A rail vehicle, comprising: a plurality of cars coupled to one
another to form a vehicle train, each of said cars having at least
one bogie; a brake system containing: at least one pressing part;
an actuator configured for mounting in said bogie of the rail
vehicle and configured to generate a braking movement of said at
least one pressing part with a braking force; an electric supply
line; an energy store connected to said actuator via said electric
supply line; a brake controller for making available control
signals and performing open-loop or closed-loop control of said
brake system; a data line; said actuator having a logic unit and a
control connection connected to said brake controller via said data
line for receiving the control signals, said control connection
connected to said logic unit configured to set the braking force in
dependence on the control signals, said actuator further having
means for generating the braking force for said at least one
pressing part and a supply connection for connecting said actuator
to said energy storage unit.
36. The rail vehicle according to claim 35, wherein said brake
system is one of a plurality of brake systems, each of said cars
has at least one of said brake systems.
37. The rail vehicle according to claim 36, further comprising a
vehicle data line, said brake systems are connected to one another
via said vehicle data line.
38. The rail vehicle according to claim 37, wherein each said brake
controller is connected to said vehicle data line via a vehicle bus
interface.
39. The rail vehicle according to claim 35, further comprising an
electrical safety loop extending through all said cars, wherein
each said actuator is connected to said electrical safety loop.
40. The rail vehicle according to claim 36, wherein each of said
brake systems has a converter unit connected to said brake
controller; and further comprising a main air line extending
through all of said cars and conducting a pneumatic control
pressure, said converter unit of each of said brake systems is
connected to said main air line.
Description
[0001] The invention relates to an actuator for a brake system of a
rail vehicle having means for generating a braking movement of at
least one pressing part with a braking force F and with a supply
connection for connecting the actuator to an energy storage unit,
wherein the actuator is configured in its entirety for mounting in
a bogie of the rail vehicle.
[0002] The invention also relates to a brake system for braking a
rail vehicle having an actuator which is configured in its entirety
for mounting in a bogie of the rail vehicle and which is configured
to generate a braking movement of at least one pressing part with a
braking force F, an energy store which is connected to the actuator
via a supply line and a brake controller which makes available
control signals and has the purpose of performing open-loop or
closed-loop control of the brake system.
[0003] The invention also relates to a rail vehicle having a
plurality of cars which are coupled to one another to form a
vehicle train, wherein each car has at least one bogie and at least
one air spring.
[0004] Pneumatic brake systems for rail vehicles are known from the
prior art. Pneumatic brake systems usually have a car-side brake
controller which accesses control valves which can be actuated
electrically. On the car side, a compressor is provided which
compresses atmospheric air to acquire compressed air, and the
compressed air is made available in a compressed air store. The
compressed air store can therefore also be referred to as an energy
store. The energy store is usually connected to an actuator via
pipe connections and/or hose connections, wherein the control
valves which can be actuated are arranged in the pneumatic
connecting line between the energy store and the actuator. An
actuator generally has a brake cylinder and brake calipers or brake
activation units (for example block brake unit). The brake calipers
or brake activation units are each provided with a pressing part,
such as for example a brake lining, which lies opposite a brake
disk which rotates during travel of the rail vehicle. A brake
piston is movably arranged in the brake cylinder, wherein the brake
piston, together with the brake cylinder, bounds a brake chamber in
a seal-forming fashion, to which brake chamber pressure can be
applied by the energy store. The pressure which is generated in the
brake chamber is set by the brake controller using the control
valves which can be actuated. A change in pressure brings about a
movement of the brake piston in the brake cylinder with a braking
force which is applied to the pressing part via an expedient lever
mechanism. Frictional engagement occurs between the pressing part
and the brake disk. Electropneumatic brake systems are voluminous
and contribute with their high own weight to a high energy
consumption of the rail vehicles.
[0005] DE 10 2006 044 022 A1 discloses a self-energizing hydraulic
brake. Furthermore, self-energizing electromechanical brakes in the
form of wedge brakes have been disclosed in the prior art.
[0006] The object of the invention is to make available an
actuator, a brake system and a rail vehicle of the type mentioned
at the beginning which permit secure braking of the rail
vehicle.
[0007] The invention achieves this object on the basis of the
actuator mentioned at the beginning by means of a control
connection for connecting a data line and by means of a logic unit
which is connected to the control connection and which is
configured to set the braking force as a function of a control
signal which is transferred over the data line.
[0008] Taking the brake system specified at the beginning as a
basis, the invention achieves the object in that the actuator has a
control connection which is connected to the brake controller via a
data line in order to receive the control signals, wherein the
control connection is connected to a logic unit of the actuator
which is configured to set the braking force as a function of the
control signals.
[0009] Taking the rail system specified at the beginning as a
basis, the invention achieves the object by means of a rail vehicle
having a brake system according to the invention and/or an actuator
according to the invention.
[0010] According to the invention, a "smart" actuator is made
available, wherein the smart actuator has a logic unit which
assists in setting the braking force. For this purpose, the smart
actuator receives, via its control connection, a control signal
such as, for example, a setpoint value. The control signal is, for
example, processed and subsequently transmitted to the logic unit.
The logic unit performs the setting of the braking force as a
function of said control signal. In this context, the intelligent
actuator is arranged with all its components in the bogie of the
rail vehicle. Since the car-side brake controller has to be
connected to the actuators arranged outside of the car, exclusively
for the purpose of transmitting one or more control signals, a
simple data line, bus and/or wire connection is sufficient between
these components. Complex pneumatic, hydraulic or mechanical
connections between the car-side controller and the actuators of
the bogies are avoided according to the invention. This simplifies
the configuration, the installation and the costs of a brake system
according to the invention.
[0011] Each actuator according to the invention expediently has a
braking force detection unit for detecting a measured variable from
which the generated instantaneous braking force F can be derived as
an actual value, wherein said braking force detection unit is
connected to the logic unit. The configuration of the braking force
detection unit is self-evidently dependent on the means for
generating a braking force of the actuator. These means can
basically be configured in any desired way according to the
invention and can be embodied, for example, in an electropneumatic,
electrohydraulic or electromechanical fashion. Depending on the
configuration of said means, the braking force detection unit
detects a measured value, for example a hydraulic pressure or a
current which is generated by the actuator or else a movement or
deformation of a part of a transmitting lever mechanism, wherein a
braking force is derived on the basis of the measured value. The
measured value is transferred, for example, to the logic unit which
sets the braking force on the basis of the control signal which is
also transmitted, in such a way that the detected actual value
corresponds as precisely as possible to a setpoint value predefined
by a superordinate controller. In other words, the smart actuator
makes available according to the invention a setpoint/actual value
control process, wherein according to the invention the setpoint
value is made available to the smart actuator by the superordinate
brake controller.
[0012] The setpoint/actual value control process also remains
active during emergency braking or rapid braking. Since the
setpoint/actual value control process is carried out by the
actuator itself, this control remains active even in the event of a
failure or fault of the data lines or buses of the rail vehicle. As
is also explained in more detail below, the setpoint value is
predefined as a function of the payload of the rail vehicle. For
this purpose, the state of a supporting spring, for example the
pressure in an air spring, on which the car body of the respective
cars is supported, is expediently detected with an expedient
sensor. Braking therefore always takes place in a load-corrected
fashion. This also applies to a rapid braking operation or
emergency braking operation. If the data line is fault free, the
braking also occurs with anti-skidding protection. This even
applies to emergency braking operations.
[0013] According to one preferred refinement of the invention, the
supply connection is an electrical supply connection which can be
connected to an electrical energy supply line and has output
terminals at which a supply voltage drops when the actuator
operates. According to this advantageous refinement, the energy
store is connected to the actuators arranged in the bogie via an
electrical conductor. The connection between the car-side
components and the brake system components of the bogie is
therefore made exclusively by means of optical and/or electrical
lines. The complex hydraulic or pneumatic connections between the
bogie components and the components of the brake system arranged in
the car of the rail vehicle are therefore eliminated.
[0014] The data line for transmitting the control signals is
expediently an electrical data line. Of course, a connection via
optical waveguides is also possible within the scope of the
invention.
[0015] If the energy store is an electrical energy store and is
connected to the supply connection via an electric line, a supply
voltage drops at the output terminals of the supply connection.
This supply voltage is used, for example, to generate the braking
force or to initialize the build-up of braking force. The control
process which is necessary here for controlling or setting the
braking force is performed, as has already been stated, by the
logic unit of the actuator. Electrical energy stores are, for
example, batteries, accumulators, supercaps, capacitors, fuel cells
or the like.
[0016] The means for generating the braking force advantageously
have an electromechanical force unit which is connected to the
supply connection and is configured to generate a mechanical
triggering force as a function of electrical energy which is made
available via the supply connection. According to this advantageous
development, an electromechanical force unit is provided which
makes available only a triggering force which is the cause of the
further braking operation. The triggering force brings about
original frictional engagement between the pressing part and a
moving mass which is to be braked. This original frictional
engagement leads, for example in the case of self-energizing
brakes, to boosting of the braking force without additional energy
having to be introduced into the brake system from the outside.
[0017] The electromechanical force unit is expediently an electric
motor, an electric pump or a piezoelement. The electro-mechanical
force unit interacts, for example, with a force store such as, for
example, a spring to be tensioned, a hydraulic accumulator or
hydraulic cylinder. The force stores are loaded by the force unit
by, for example, the spring being tensioned.
[0018] The means for generating a braking movement are expediently
self-energizing. As has already been stated further above, the
electromechanical force unit serves in this case only to make
available a low triggering force which initiates a braking process.
Owing to the self-energizing effect of the electromechanical force
unit, a strongly increasing braking force occurs, wherein the
increasing braking force is subject to the control by the logic
unit. Such self-energizing means for generating a braking force
are, for example, a self-energizing hydraulic brake, which is
already known from the prior art, or else also a self-energizing
electromechanical brake, which can also be referred to as a wedge
brake. The wedge brake is also already known to a person skilled in
the art. The advantage of the use of self-energizing
force-generating means is to be seen in the fact that only a small
force has to be applied to initiate a braking process. This has, in
particular, advantages in the configuration of the connection of
the smart or inventive actuator via the energy supply line to the
force store which is arranged, for example, on the car side.
Furthermore, little energy is consumed during braking. The
operating costs are therefore lowered. Finally, the brake can be
embodied in a more compact and lightweight fashion than would be
the case in brakes without self-energization.
[0019] Electrically drivable emergency triggering means are
advantageously provided for releasing the brake, and an additional
connection which is electrically connected to the emergency
triggering means is provided for connecting an external electrical
energy supply. By using the emergency triggering means it is
possible to release from the outside the brake which is connected
to the actuator according to the invention. For this purpose, for
example a predefined supply voltage is applied to the additional
connection, with the result that the emergency triggering means
which comprise, for example, an electric motor and a spindle
tension a spring and therefore release the brake.
[0020] In a further expedient refinement of the brake system
according to the invention, the energy store is an electrical
energy store which makes available an electrical supply voltage on
the output side. According to this variant of the invention, the
energy store is connected to the actuator according to the
invention via an electrical connecting line.
[0021] The brake system according to the invention expediently has
a converter unit which is connected to the brake controller and/or
to the actuator, wherein the converter unit has at least one
converter which makes available an electrical variable on the
output side as a function of a pressure which is fed in on the
input side or else of an electrical signal, wherein the converter
or converters is/are provided for connection to a signal generator,
detecting the state of the supporting spring, of the rail vehicle
and/or of at least one pneumatic line of a rail vehicle. According
to this expedient development, it is possible to control the brake
system via pressure lines, for example via what is referred to as a
main air line (HL). The converter unit is expediently connected to
the brake controller and/or to the smart actuators via an
electrical or optical data line. The conversion of a pneumatic
control pressure is carried out using converters which are
commercially available and are therefore very well known to a
person skilled in the art. There is no need for precise
presentation of the method of operation of such converters here.
The converters make available, on the output side, an electrical or
optical measured variable which corresponds to the pneumatic or
hydraulic pressure or signal present on the input side. The
converter unit transmits the measured variable acquired in this way
to the brake controller via the data line. Of course, it is
possible to process the measured value before this. In this context
it is also expedient to connect the converter unit to the energy
store via an electrical supply line. The energy store makes
available the electrical energy which is possibly required by the
converter. Furthermore, the converter unit can be arranged as
desired and can, for example, also be arranged in the bogie or else
on the car side. The supporting spring is embodied, for example, as
an air spring, secondary spring, steel spring, flexicoil spring
with a rubber additional spring or a hydropneumatic spring. In the
case of an air spring, the converter unit communicates with the air
spring via a pneumatic line.
[0022] The data line is expediently a data bus which connects brake
controller, each actuator and each converter unit to one another.
Such data buses are best known in the field of industrial control
and are configured for the exchange of communications between a
plurality of components of a system, with the result that
particularly effective and rapid communication is made available,
and said communication also satisfies the respective safety
requirements.
[0023] The actuators are expediently connected to an electrical
safety loop for transmitting control signals. The electrical safety
loop is already known from the field of pneumatic brakes. It
usually serves to trigger an emergency braking instruction, for
example as a result of activation of a car-side safety switch. Such
activation opens the electrical safety loop, after which the logic
unit of the actuator according to the invention ensures rapid
braking occurs.
[0024] Means for detecting the load state and/or the mass of the
rail vehicle which are connected to actuators are advantageously
provided, wherein said actuators limit the braking force to be set
as a function of the load state and/or the mass. These means for
detecting the load state are, for example, the above-mentioned
converters of the converter unit. However, within the scope of the
invention other sensors are also possible. Each actuator is
expediently connected to said means.
[0025] According to one advantageous development of the rail
vehicle according to the invention, each car of the vehicle train
of the rail system has at least one brake system of the type
mentioned above. According to one variant, each car has two such
brake systems, wherein, for example, each brake system has a
converter unit which is respectively connected to an air spring of
said car. Of course, each converter unit can also be connected to
two air springs of the same car if it is expedient to do so. If
only one brake system is provided for each car and if, for example,
a converter is part of the brake system according to the invention,
said converter is, of course, connected to one or more air springs
or else to all of the air springs of a car depending on
requirements.
[0026] As has already been stated above, a safety loop expediently
extends through the entire vehicle train of the rail vehicle. The
safety loop is connected to each of the actuators. The safety loop
is, for example, a simple wire connection.
[0027] Furthermore, according to one preferred refinement, the rail
vehicle has a compressed air line, for example a main air line,
which extends through all cars and has the purpose of conducting a
pneumatic control pressure. The main air line is connected to each
converter unit.
[0028] A vehicle train data line expediently serves to connect the
brake systems of a rail vehicle.
[0029] Further expedient refinements and advantages of the
invention are the subject matter of the following description of
exemplary embodiments of the invention with reference to the
figures of the drawing, wherein identical reference symbols refer
to identically acting components, and wherein
[0030] FIG. 1 shows an exemplary embodiment of the actuator
according to the invention in a schematic illustration,
[0031] FIGS. 2 to 4 show exemplary embodiments of a brake system
according to the invention in a schematic view, and
[0032] FIGS. 5 and 6 show a schematic illustration of exemplary
embodiments of the rail vehicle according to the invention.
[0033] FIG. 1 shows an exemplary embodiment of an actuator 1
according to the invention in a schematic view. The actuator 1 has
a logic unit 2 which is connected to a control connection 3 via
electrical or optical connecting lines. A supply connection 4,
which can be connected to an energy store, serves to supply energy,
with the result that a supply voltage drops across the output of
the supply connection 4.
[0034] Furthermore, the actuator 1 has means for generating a
braking movement 5, for example in the form of a self-energizing
electrohydraulic brake 5. The self-energizing electrohydraulic
brake 5 has an electromechanical force unit (not illustrated
figuratively) such as, for example, an electric motor or a pump
which is linked to a store and which builds up a hydraulic pressure
which triggers the braking and which ensures the generation of a
braking movement with a braking force F in a hydraulic brake
cylinder which is also part of the self-energizing hydraulic brake
5. The braking force F is applied to a pressing part holder 7 via
an expedient lever mechanism 6, which pressing part holder 7 is
equipped with a pressing part 8 which is arranged opposite a brake
disk 9 of a rail vehicle (not illustrated figuratively). The
pressing part 7 in the exemplary embodiment shown is a brake
lining. The term actuator also comprises here the brake caliper 7
with its pressing part 8. During travel of the rail vehicle, a
rotational movement of the brake disk 9 occurs, said brake disk 9
being connected in a rotationally fixed fashion to a running axle
of the rail vehicle. Pressing the pressing part 8 with frictional
engagement against the brake disk 9 causes negative acceleration of
the rail vehicle to occur and/or a build-up of deceleration force
at the wheel.
[0035] The actuator 1 also has a braking force detection unit 10
with which an electrical signal which corresponds to the braking
force is transmitted to the logic unit.
[0036] The self-energizing brake 5 is connected to the supply
connection 4 in order to drive the electromechanical force unit,
which is an electric motor in the exemplary embodiment shown. This
is done by means of an electrical connection, illustrated in FIG. 1
and in the other figures by a continuous line. Pneumatic
connections are also represented by dashed lines. The setting of
the setpoint value of the actuator 1 is carried out by a
superordinate brake controller of the rail vehicle. The brake
controller makes available, for each actuator 1, a setpoint value
which is transmitted from the brake controller to the control
connection 3 and therefore to the logic unit 2. On the basis of the
connection between the braking force detection unit 10 and the
logic unit 2, the logic unit 2 has both the setpoint value and an
actual value. Furthermore, the logic unit 2 is equipped with an
implemented or programmed logic which can be used to allow it to
control, for example, the self-energizing hydraulic brake 5 in such
a way that the actual value corresponds as precisely as possible to
the setpoint value. This makes available a smart actuator 1.
[0037] With the exception of the lever mechanism 6 and the pressing
part holder with pressing part 7, all the components of the
actuator 1 according to the invention are arranged in or on a
common housing 11. The housing 11 is mounted in a bogie of the rail
vehicle (not shown) using expedient attachment means such as, for
example, screws or the like. Since brake caliper 7 and the lever
mechanism 6 are also arranged in the bogie, all the components of
the actuator 1 are configured for mounting in the bogie and
correspondingly designed.
[0038] FIG. 2 shows an exemplary embodiment of the brake system 12
according to the invention which has a plurality of actuators 1
according to FIG. 1. The number of the actuators 1 is dependent on
the respective request. The number of the actuators 1 is therefore
represented in a variable fashion by the circles. For example, the
brake system 12 comprises two actuators 1 for each axle of the
bogie.
[0039] Two-axle bogies therefore have four actuators 1.
[0040] Furthermore, the brake system 12 comprises a superordinate
brake controller 13 and an energy store 14. The brake controller 13
is connected via an electrical data line, what is referred to as a
data bus 15, to the smart actuators 1 which are assigned thereto.
The data bus 15 is, for example, an industrial bus system which is
known to a person skilled in the art, with the result that there is
no need to go into details on this here. It is to be noted that the
data bus 15 permits both an exchange of information between the
brake controller 13 and the actuators 1 as well as among the
actuators 1 themselves. The energy store 14 is connected via
electrical supply lines 16 to the supply connection 4, see FIG. 1,
of each actuator 1. Said energy store 14 serves to make available
at least part of the energy necessary to brake and release the
brake.
[0041] FIG. 3 shows a further exemplary embodiment of the brake
system 12 according to the invention as in FIG. 2, wherein,
however, in contrast to the exemplary embodiment shown in FIG. 2 a
converter unit 17 is provided which can be used to take into
account the load state of the car of the rail vehicle to be braked
or of the entire rail vehicle during braking. For this purpose, the
converter unit 17 is connected via a pneumatic interface 18 to an
air spring 19. It is to be noted here that a car body 20 of the
rail vehicle is mounted by means of the air spring 19 on a bogie
(not illustrated) of the rail vehicle. Depending on the load state,
the air spring is therefore compressed to differing degrees, with
the result that the air pressure prevailing in the air spring 19 is
a measure of the load state of the car 20. In rail vehicles without
a pneumatic secondary spring, the load signal can also be an
electrical variable. The converter unit 17 has a converter (not
shown figuratively) to which the pressure of the air spring 10 is
applied on the input side. On the output side, the converter makes
available a current signal which corresponds to the pressure of the
air spring 19. The converter unit 17 also has means for processing
measured values, which means sample the current signal. The sampled
values acquired in the process are digitized by an analog/digital
unit. The digital current signal is subsequently converted into a
laden weight by a calculation unit of the converter unit 17, said
laden weight constituting a measure of the load state. The laden
weight is subsequently transmitted via the data bus 15 to the
superordinate brake controller 13 and the smart actuators 1. It is
apparent that in FIG. 3 the superordinate brake controller 13 is
represented by two separate units 13. This is intended to clarify
that the brake controller 13 is of redundant design, with the
result that in the case of failure of a brake controller 13 a
second brake controller 13 permits reliable braking. Of course, it
is also possible to distribute the components of a brake controller
between two housings which are arranged separately. In FIG. 3, the
two brake controllers 13 exchange data with the actuators 1 and the
converter unit 17 via the data bus 15. The brake controllers 13
determine, on the basis of the transferred load state, setpoint
values which are then transmitted to the actuators.
[0042] The exemplary embodiment according to FIG. 4 corresponds
very largely to the exemplary embodiment shown in FIG. 3, wherein
the pressure of a pneumatic main air line 21 is additionally
applied on the input side to the converter unit 17 in the exemplary
embodiment according to FIG. 4. For this purpose, the main air line
21 is pneumatically connected via a connecting line 22 to the
converter unit 17. The converter unit 17 according to FIG. 4
therefore has two converters, which each make available an
electrical signal as a function of the pressure of the main air
line or of the air spring 19. In this way, a desired braking
deceleration can be predefined to the brake system 12 according to
FIG. 4 via the main air line. The converter unit 17 converts the
pressure of the main air line 21 into a corresponding electrical
and, for example, digital signal and makes this available to the
brake controller 13 via the data bus 15, which transmits a setpoint
value corresponding to the pressure of the main air line 21 or a
corresponding control signal to the actuators 1. Said actuators 1
then generate, on the basis of their internal logic, an actual
value which corresponds very largely to the setpoint value.
[0043] FIG. 5 is a schematic view of a car 23 (illustrated by a
dotted line) of a rail vehicle, which car 23 has two brake systems
12 according to FIG. 4. The brake systems 12 are connected to one
another via a vehicle data line 24, also a data bus. To be more
precise, the superordinate brake controllers 13 of each brake
system 12 are connected to the vehicle data bus 24. The brake
controllers 13 have an interface which is expedient for this
purpose. A braking instruction, for example from the driver of the
vehicle, can be transferred via the vehicle data line 24 to the
individual brake controllers 13 of the car 23. Each brake
controller 13 is connected via the corresponding converter unit 17
to an air spring 19 which is assigned thereto, and said brake
controller 13 generates, on the basis of the payload which is known
to it and as a function of the central braking instruction,
setpoint values for the smart actuators 1 which are assigned to it.
In this context there is no need at all for all the actuators 1
which are assigned to the brake controller 13 to receive the same
setpoint value. Within the scope of the invention it is perfectly
possible for the brake controller 13 to transmit different braking
setpoint values to each actuator 1 which is assigned to it.
Furthermore, the setpoint values of the other brake controllers 13
can differ from one another for example owing to a differing
pressure in the respective air spring 19.
[0044] In addition it is apparent that the actuators 1 are
connected to one another via an electrical safety loop 25. Such an
electrical safety loop 25 is already current practice in pneumatic
brakes. If the electrical connection of this safety loop 25 is
interrupted, each smart actuator 1 initiates an emergency braking
operation which is independent of the service brake. Such an
emergency braking operation is triggered, for example, by pressing
a car-side emergency braking button. According to the inventive
solution, such an emergency braking operation is set by the
actuators 1 with a maximum braking force, wherein the maximum value
of the braking force is calculated as a function of the payload
information from the converter unit 17. If such an emergency
braking operation occurs when communication between the converter
unit 17 and the actuator 1 is disrupted, the actuator 1 sets an
equivalent value for limiting the braking force.
[0045] FIG. 6 shows a further exemplary embodiment of a rail
vehicle according to the invention in which two cars 23 are
illustrated, said cars being each represented by a dotted line. It
is apparent that each car 23 has a brake system 12, wherein the
converter unit 17 of each brake system 12 is pneumatically
connected to two air springs 19. The measured pressure values,
detected by the converter units 17, of the air springs 19 are
transmitted to the superordinate brake controller 13 and the
actuators 1, which calculates all the setpoint values for the car
23 and sends them to the actuators 1 via the data bus 12.
Furthermore, the converter unit 17 is connected to the main air
line 21 which extends through the entire train of cars. The same
applies to the safety loop 25, which reconnects all the actuators 1
of all the brake systems 12 to one another. The brake controller 13
of each brake system 12 of a car is again connected via a vehicle
data bus 24 to the rest of the brake controllers 18 of the rail
vehicle. What has been stated in relation to FIG. 5 also
applies.
[0046] In conclusion it is to be noted that the converter unit 17
within the scope of the invention does not have to be embodied as a
separate component with a separate housing, as illustrated in the
figures. Instead, within the scope of the invention it is also
possible to configure the converter unit 17 as part of the brake
controller. The converter unit 17 is therefore accommodated in the
housing of the respective assigned brake controller. In order to
supply them with energy, all the components of the brake system, in
particular also the converter unit, can be connected to the energy
storage unit 14 within the scope of the invention. The energy
storage unit can also be the vehicle on-board power system.
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