DE202022106835U1 - Electropneumatic parking brake control device - Google Patents

Abstract

Electropneumatic parking brake control device (1) for controlling a parking brake containing at least one spring brake cylinder
a) a connection (40) for the at least one spring brake cylinder,
b) a first solenoid valve device (8) which can be controlled by means of an electronic control device (14)
c) a relay valve (18) whose pneumatic control input (20) is connected on the one hand to the first solenoid valve device
(8) and on the other hand with its working output (28) and with the connection (40) for the at least
a spring brake cylinder is connected,
d) a supply connection (2) for at least one compressed air supply, which is connected on the one hand to the first solenoid valve device (8) and on the other hand to a supply input (16) of the relay valve (18),
e) a feedback line (26) through which the working outlet (28) and the pneumatic control inlet (20) of the relay valve (18) can be connected to one another, characterized in that
f) the first solenoid valve device (8) is formed by two solenoid valves (10, 12, 30), wherein
g) a first 3/2-way solenoid valve (10) is arranged as an inlet valve between the supply port (2) and the control input (20) of the relay valve (18) and a second 2/2-way solenoid valve (12) between the first 3/2- Directional solenoid valve (10) and the control input (20) of the relay valve (18) is arranged, wherein
h) at least one throttle element (30) is arranged in the feedback line (26) in such a way that the working output and the pneumatic control input (20) of the relay valve (18) are always in fluid communication with one another.

Description

The invention relates to an electropneumatic parking brake control device for controlling a parking brake containing at least one spring brake cylinder, as well as a brake system of a vehicle and a vehicle with such an electropneumatic parking brake control device.

On commercial vehicles, including towing vehicle-trailer combinations and rail vehicles, parking brakes (also called parking brakes) are equipped with spring-loaded brake cylinders which, in the released position, apply compressed air to a spring compression chamber and thus keep the spring tensioned, while the spring compression chamber is vented for braking, i.e. it is connected to atmospheric pressure, so that the Brake cylinder generates a braking force under the action of the spring.

Both purely pneumatically operated parking brakes are known, which are operated with a bistable parking brake valve to be actuated by the driver, and electropneumatic systems with a bistable electromechanical valve, for example a pneumatic relay valve, which is controlled by an electromechanical, bistable solenoid valve. Both valve positions for "parking brake" and "release" must be "stable", i.e. remain in the selected end position without the influence of a person or electrical energy.

In the prior art, the bistability is therefore either purely pneumatic with downstream relay valves and multiple actuating and control pistons, for example DE 10 2009 016 983 A1 or DE 10 247 812 C1 , which causes a lot of effort and a large installation space or is ensured via bistable solenoid valves with a downstream relay valve, as in DE10 2006 055 570 B4 is described. However, bistable solenoid valves are expensive and prone to failure in practice.

Furthermore, from generic DE 10 2007 061 908 B4 known to realize the bistability by a feedback relay valve, the feedback being realized by a first 3/2 solenoid valve which, when not energized, connects the output of the relay valve to its control chamber and, when energized, separates the control chamber of the relay valve from its output and instead to the Output of a second 3/2 solenoid valve connects that this output can either connect to supply or to atmosphere. However, this method has the disadvantage that two expensive 3/2 solenoid valves are used and that the pressure with the second 3/2 solenoid valve can only be switched between supply and atmosphere without permanent loss of air, but cannot be adjusted to an intermediate value.

The invention is based on the object of further developing an electropneumatic parking brake control device of the type mentioned at the outset in such a way that the basic requirements placed on parking brakes of heavy commercial vehicles, such as engaging and releasing the parking brake with bistable behavior, controllability of the brake pressure for the auxiliary brake, etc., can be met as cost-effectively as possible and with minimal Space can be realized. Furthermore, it is the object of the invention to specify an associated brake system and a vehicle with such a parking brake control device.

This object is achieved according to the invention with regard to the parking brake control device by the features of claim 1 and with regard to the brake system or the vehicle by the subject matter of claims 13 and 14. Preferred embodiments are specified in the dependent claims.

According to the present invention, an electropneumatic parking brake control device is provided for controlling a parking brake containing at least one spring-loaded brake cylinder, with a connection for the at least one spring-loaded brake cylinder, a first solenoid valve device that can be controlled by means of an electronic control device, a relay valve, the pneumatic control input of which is connected on the one hand to the first solenoid valve device and on the other hand to its working output and to the connection for the at least one spring brake cylinder, a supply connection for at least one compressed air supply, which is connected on the one hand to the first solenoid valve device and on the other hand to a supply input of the relay valve, and a feedback line, through which the working output and the pneumatic control input of the relay valve are connected to one another are connectable. The first solenoid valve device is formed by two solenoid valves, with a first 3/2-way solenoid valve being arranged as an inlet valve between the supply connection and the control input of the relay valve, and a second 2/2-way solenoid valve being arranged between the first 3/2-way solenoid valve and the control input of the relay valve is, wherein in the feedback line at least one throttle element is arranged such that the working output and the pneumatic control input of the relay valve are always in flow communication with each other.

The invention therefore proposes that starting from DE 10 2007 061 908 B4 the two 3/2 solenoid valves are replaced by a throttle element in combination with a first 3/2-way solenoid valve and a second 2/2-way solenoid valve, each with a passage position and a passage or venting position, the first 3/2-way solenoid valve as Inlet valve is connected between the control input of the relay valve and the supply connection and the second 2/2-way solenoid valve is connected between the control input of the relay valve and the first 3/2-way solenoid valve.

The basic idea of the invention is that bistability is similar to that of DE10 2007 061 908 B4 is represented by feedback of a relay valve. In contrast to this, however, the first 3/2-solenoid valve is controlled by a very inexpensive throttle element and the second 3/2-solenoid valve by a combination of a 3/2-way solenoid valve and a 2/2-way solenoid valve, which are in the de-energized venting position or closed/ are blocked, replaced. These form a first solenoid valve device in which, in the de-energized state, the control chamber of the relay valve is shut off both from the compressed air supply and from the atmosphere.

For the purpose of feedback, at least one throttle element can therefore be arranged according to the invention in the feedback line drawn between the working output and the pneumatic control input of the relay valve, such that the working output and the pneumatic control input of the relay valve are always in flow communication with one another. A feedback circuit is created via the feedback line, which is provided with the at least one throttle element, in that the pressure at the working outlet of the relay valve or at the connection for the at least one spring-loaded brake cylinder is fed back into the control input of the relay valve, as a result of which the last assumed state of the at least one spring-loaded brake cylinder, for example its application position is securely locked.

A throttle element should be understood to mean an element that narrows the flow cross section of the feedback line. The air mass flow between the working outlet and the pneumatic control input of the relay valve is limited by the throttle element (in both flow directions) to a value which is, for example, lower than the air mass flow which can be generated at the pneumatic control input of the relay valve by means of the first solenoid valve device. As a result, on the one hand, the desired feedback is always provided, but on the other hand, an override of the feedback by the first solenoid valve device is possible.

Apart from the at least one throttle element, preferably no further elements such as switching valves, proportional valves, pressure-limiting valves etc. impeding or blocking the air mass flow between the working output and the pneumatic control input of the relay valve are arranged in the feedback line.

Since this design is similar to an EBS pressure control valve device, the same solenoid valves can be used here as there and both devices can be manufactured on the same production line and at least partially with the same casting tools, which results in cost savings. The throttle element in the feedback line, which can be implemented inexpensively and is formed, for example, only by a narrow channel, also contributes in particular to this.

Compared to solutions in which other valves are required in addition to the relay valve to produce the bistable behavior, the invention requires fewer parts. Compared to solutions with expensive bistable solenoid valves, whose susceptibility to high accelerations (e.g. flame impact on the frame in the vicinity of the solenoid valve) is relatively high, whose failure behavior is very difficult to represent and whose service life is limited, the invention has the advantage that these disadvantages are largely avoided .

Overall, there are advantages in terms of a simple and inexpensive structure, a small space requirement and a robust, proven technology. Furthermore, the invention allows the use of modular components such as 3/2 or. 2/2 solenoid valves and relay valves.

According to one development, the electronic control device is connected to an electric parking brake signal connection for an electric parking brake signal generator, via which parking brake signals can be fed into the electronic control device.

The electronic control device can also be connected to a signal connection for the control of signals from which the electronic control device generates parking brake signals. Signals can then preferably also be fed into this signal connection or also into the parking brake signal connection of the parking brake control device, for example via a vehicle data bus, from which the control device then itself generates parking brake signals. Such signals can in particular be signals which allow a standstill of the vehicle to be detected within the framework of a driver assistance system such as a starting assistance system, in which case, for example, when the vehicle standstill is detected on the basis of these signals, which are then vehicle standstill signals, the electronic control device generates a parking brake signal for applying the parking brake. Alternatively, signals fed into the parking brake control device, from which the electronic control device of the parking brake control device then generates parking brake signals, could originate from any other driver assistance system, such as an ACC system (Adaptive Cruise Control) in the event that the parking brake is used as an auxiliary brake while driving . In all of these cases, the parking brake signals are therefore not automatically generated as a function of an actuation of the parking brake signal generator, but by one or more driver assistance systems.

For this purpose, this signal connection or the parking brake signal connection is designed so that it can be connected to a vehicle data bus in order to control signals routed via the vehicle data bus into the electronic control device, which then generates parking brake signals there depending on these signals. The communication between the electronic control device and the vehicle data bus is then preferably bidirectional.

The first 3/2-way solenoid valve particularly preferably has a currentless venting position and an energized open position, and the second 2/2-way solenoid valve has a currentless blocking position and an energized open position.

In the event of a failure of the electrical power supply, the control input of the relay valve is then decoupled from both the supply connection and the ventilation or atmosphere, so that no control compressed air can get from the supply connection to the relay valve or escape from it via the ventilation or pressure sink.

In particular, a (set) pressure at the control input of the relay valve can be locked in by the second 2/2-way solenoid valve at the control input of the relay valve by the second 2/2-way solenoid valve being controlled or switched into the locked position.

According to one development, it is provided that when a parking brake signal representing a “driving” state is input or generated in the electronic control device or in the electronic control device, the first 3/2-way solenoid valve is in the open position and the second 2/2-way solenoid valve is initially in the open position controls. The first 3/2-way solenoid valve and the second 2/2-way solenoid valve are therefore initially switched to the open position over a specific period of time, for example by energizing them. After the specified period of time has elapsed, which is necessary for the pressure at the connection for the at least one spring brake cylinder to have reached the full release pressure of the spring brake cylinder, the second 2/2-way solenoid valve is then switched to the blocked position. This means that the control input is only connected to the working output in a throttled manner. Any slight leakage to a vent or pressure sink that may occur, e.g. due to a defect, would be compensated for via the inlet seat of the relay valve.

When a parking brake signal representing an “apply parking brake with a specific brake pressure value” state is input or generated in the electronic control unit or in the electronic control unit, it controls the first 3/2-way solenoid valve and/or the second 2/2-way solenoid valve depending on the the respective brake pressure value in the blocked position or vented position or in the open position. This is the case in particular in the context of auxiliary or emergency braking, in which the parking brake has to replace or support the service brake.

For an increase in pressure at the connection for the at least one spring brake cylinder, the first 3/2-way solenoid valve and the second 2/2-way solenoid valve are controlled in the open position, for example, so that the pressure at the control input of the relay valve and thus also at the connection for the at least one spring brake cylinder is increased.

For a pressure reduction at the connection for the at least one spring brake cylinder, for example, according to 2 the second 2/2-way solenoid valve is switched to the open position and the first 3/2-way solenoid valve is switched to the venting position, so that the pressure at the control input of the relay valve and thus also at the connection for the at least one spring brake cylinder is reduced.

In the first case, the electronic control device can control the first 3/2-way solenoid valve and, in the second case, the second 2/2-way solenoid valve alternately or in pulses in the closed position or vent position and over a longer period of time in the open position in order to avoid a ramped or gradual increase in pressure or To achieve pressure drop, which is just for a sensitive dosing or for a control of the parking brake force or the parking brake pressure is particularly advantageous in the context of auxiliary or emergency braking.

The air flow through the throttle element, which may result depending on the current pressure difference between the working output and the control input of the relay valve, as well as a possible slight leak to a pressure sink or the vent or to the reservoir pressure, e.g of the 2/2-way solenoid valve acting in the opposite direction. According to a preferred development, when a parking brake signal representing a “parking brake” state is input or generated in the electronic control unit or in the electronic control unit, the first 3/2-way solenoid valve can be in the venting position and the second 2/2-way solenoid valve initially in the open position and then steer in locked position. The second 2/2-way solenoid valve is therefore initially switched to the open position over a certain period of time, for example by energizing, while the first 3/2-way solenoid valve remains in the venting position. After the specified period of time has elapsed, which is necessary for the pressure at the connection for the at least one spring-actuated brake cylinder to have fallen at least so far that the relay valve remains in the venting position even after the second 2/2-way solenoid valve has been switched off, the second 2/2 - Directional solenoid valve controlled in blocking position.

This means that the control input is only connected to the working output in a throttled manner. Any slight leakage towards the reservoir pressure, e.g. due to a defect, would be vented via the outlet seat of the relay valve.

Particularly preferably, the electromagnetic parking brake control device can be provided for a towing vehicle/trailer combination and then has at least one connection for a trailer control valve, which can be connected to the connection for the at least one spring brake cylinder.

In order to determine the pressures acting in the electropneumatic parking brake control device and to monitor functions and operating states, pressure sensors can be provided at different points.

At least one pressure sensor can be connected to the connection for the at least one spring brake cylinder and/or at least one pressure sensor to the control input of the relay valve and/or at least one pressure sensor to the connection for the trailer control valve and/or at least one pressure sensor between the first 3/2 -Way solenoid valve and the second 2/2-way solenoid valve may be provided, which controls a signal representing an actual pressure into the electronic control device.

Accordingly, the electronic control device can be designed so that it carries out a target/actual comparison as part of a pressure control and/or a pressure plausibility check and on the basis of a signal representing an actual pressure and a signal representing a value for a target pressure /or carries out a determination of the supply pressure present at the supply connection.

If, for example, a pressure sensor is connected to the working outlet of the relay valve and can therefore also be connected or is connected to the connection for the at least one spring-loaded brake cylinder or to the connection for the trailer control valve, the actual pressure and from it the operating state of the at least one spring-loaded brake cylinder ( released, clamped or partially released or clamped) can be determined. The same then also applies to the operating state of the trailer brakes, which can be determined from the actual pressure at the connection for the trailer control valve. Furthermore, a pressure control circuit is realized in which the first solenoid valve device forms the actuators in conjunction with the relay valve.

If a pressure sensor is connected to the control input of the relay valve, the actual pressure controlled by the first 3/2-way solenoid valve and the second 2/2-way solenoid valve can be determined very quickly, which enables high dynamics in the pressure control circuit. In addition, the operating state of the at least one spring-loaded brake cylinder (released, applied or partially released or applied) and the actual brake pressure prevailing there can be approximately determined, taking into account the transfer behavior of the relay valve. The same then also applies to the operating status of the trailer brakes.

In particular, such a pressure sensor can be used to determine an actual pressure that is blocked by the blocking position of the second 2/2-way solenoid valve at the control input of the relay valve.

If a first pressure sensor is connected to the control input and a second pressure sensor is connected to the working output of the relay valve, this enables error detection by means of a plausibility check. For example, the actual pressure values of the first and second pressure sensors depending on the operating state, taking into account certain tolerances, are in a certain relation to each other. The error detection or error monitoring can be carried out quickly, completely and in several operating states. Furthermore, faster pressure regulation is possible than if only one pressure sensor is arranged at the working outlet of the relay valve or one pressure sensor at the control input of the relay valve. If an additional pressure sensor is connected to the connection of the trailer control valve together with a pressure sensor at the working output and/or at the control input of the relay valve, the supply pressure can be measured directly at the supply connection in several operating states without having to set the "driving" operating state. Furthermore, a quick error detection is possible by means of a plausibility check. For example, the actual pressures of the pressure sensors must display the same values when the solenoid valves are switched in such a way that a pressure connection between the pressure sensors comes about. As before, it is also possible to determine the reservoir pressure in several operating states. Advantageously, this also allows pressure regulation of the pressure at the connection for the trailer control valve if the “extending brake” operating state is provided, in which only the trailer brakes, but not the towing vehicle brakes, are applied in a controlled manner to stretch the towing vehicle-trailer combination.

According to a preferred embodiment, the supply connection is protected by a non-return valve.

According to one development, at least the relay valve, the first solenoid valve device, the check valve, the electronic control device, the at least one throttle element and the supply connection, the connection for the at least one spring-actuated brake cylinder and the parking brake signal connection can be designed in one structural unit.

This results in a compact unit, which can be further expanded as a basic module.

Preferably, the non-return valve and at least part of the feedback line are arranged outside the assembly.

An electro-pneumatic modulator (EPM) that is commonly used with electronically controlled brakes (EBS) can then be used as a structural unit and modified or supplemented accordingly.

The invention also relates to a brake system of a vehicle containing an electropneumatic parking brake control device as described above, in particular an electropneumatic parking brake system of a towing vehicle/trailer combination and in particular as an electronically controlled parking brake system (EPB).

Furthermore, the present invention relates to a vehicle with an electropneumatic parking brake control device according to the invention or a brake system according to the invention.

Further measures improving the invention are presented in more detail below together with the description of an exemplary embodiment of the invention with reference to the drawing.

• 1 ein schematisches Schaltbild einer Ausführungsform einer elektropneumatischen Parkbremssteuereinrichtung;
• 2 die Ausführungsform gemäß 1 in einem weiteren Schaltzustand; und
• 3 die Ausführungsform gemäß 1 in einem weiteren Schaltzustand.

Show it:

• 1 a schematic circuit diagram of an embodiment of an electropneumatic parking brake control device;
• 2 the embodiment according to 1 in another switching state; and
• 3 the embodiment according to 1 in another switching state.

1 shows a schematic circuit diagram of a preferred embodiment of an electropneumatic parking brake control device 1. The electropneumatic parking brake control device 1 preferably represents a component of an electropneumatic braking device of a towing vehicle-trailer combination, in particular an electronically controlled braking system (EBS) and is arranged on the towing vehicle.

The electropneumatic parking brake control device 1 has a supply connection 2 which is protected by a check valve 4 .

A supply line 6 extends from the supply connection 2 to a first solenoid valve device 8 with a first 3/2-way solenoid valve 10 as an inlet valve and a second 2/2-way solenoid valve 12 as an intermediate or outlet valve.

The first 3/2-way solenoid valve 10 is de-energized in the vent position shown and the second 2/2-way solenoid valve 12 is de-energized in the blocking position shown, while both valves 10, 12 switch energized to the open position.

Both valves 10, 12 can be controlled or regulated by means of an electronic control device 14.

Furthermore, a supply input 16 of a relay valve is also connected to the supply connection 2 via the supply line 6 .

A pneumatic control input 20 of the relay valve 18 is connected via a control line 22 to the combination of inlet valve 10 (first 3/2-way solenoid valve) and intermediate or outlet valve 12 (second 2/2-way solenoid valve).

In detail, the connection between the control line 22 or the control input 20 of the relay valve 18 and the first 3/2-way solenoid valve is interrupted in the currentless blocking position of the second 2/2-way solenoid valve 12, while this connection is switched in the energized open position.

Furthermore, in the currentless blocking position of the first 3/2-way solenoid valve 10, the connection between the control line 22 or the control input 20 of the relay valve 18 and the supply port 2 is interrupted, while this connection is switched in the energized open position.

Preferably, in the de-energized blocking position of the first 3/2-way solenoid valve 10, the control line 22/the control input 20 can be connected to a vent of the first 3/2-way solenoid valve, in particular by switching or controlling the second 2/2-way solenoid valve to the open position becomes. In addition, a throttle element 30 is connected in a feedback line 26 between a working outlet 28 of the relay valve 18 and the control inlet 20 of the relay valve 18, through which the flow cross section of the feedback line 26 narrows and by means of the flow cross section narrowing the air mass flow between the working outlet and the pneumatic control inlet of the relay valve is limited or throttled.

The two solenoid valves 10, 12 are preferably spring-loaded into their de-energized position and are switched over by the control device 14 being energized.

The working output 28 of the relay valve 18 is connected by a working line 38 to a connection 40 for at least one spring brake cylinder.

Two spring brake cylinders, not shown here, are preferably connected to this connection 40 on the rear axle.

Depending on the switching position of the first 3/2-way solenoid valve 10 and the second 2/2-way solenoid valve 12 (inlet/outlet solenoid valve combination), the control line 22 or the control input 20 of the relay valve 18 is pressurized or vented, so that a pressurization or venting by increasing the amount of air by means of the relay valve 18, a corresponding ventilation of the working outlet 28 and thus of the connection 40 for the at least one spring-loaded brake cylinder entails. The relay valve 18 is constructed in a largely known manner and a control chamber connected to the control line via the control input 20 can be controlled or regulated.

A parking brake signal transmitter can be provided in signal communication with the control device 14 .

The switching states of the two solenoid valves 10, 12 are preferably determined by the control device 14, in particular as a function of a parking brake signal present at a parking brake signal connection.

The parking brake signal generator can be designed in such a way that it emits parking brake signals as a function of actuation, which represent the operating states described further below.

The control device can also be connected via the parking brake signal connection or via a further signal connection to a vehicle data bus, not shown in the figures, via which digital data can be received from other control devices and sent to them.

Instead of or in addition to the parking brake signal generator that can be operated manually by the driver, parking brake signals can also be fed into control device 14 from a further control device, for example via a vehicle data bus, for example from a driver assistance system, for example from a starting assistance system on inclines. Using signals received via such a vehicle data bus, parking brake signals can then be generated by the control device 14 itself.

For example, the parking brake can be applied automatically when the vehicle has come to a standstill, or released automatically when it is recognized that the vehicle is to drive off.

The 2 and 3 are identical in structural design to the exemplary embodiment according to FIG 1 and show in particular the other switching positions in the appropriate use of the parking brake control device shown.

• In dem in 1 gezeigten Grundzustand der elektropneumatischen Parkbremssteuereinrichtung 1 sind sowohl das erste 3/2-Wegemagnetventil 10 als auch das zweite 2/2-Wegemagnetventil 12 unbestromt, so dass über das Drosselelement 30 der Steuereingang 20 stets mit dem Arbeitsausgang 28 des Relaisventils 18 verbunden ist.

The functioning of the electromagnetic parking brake control device 1 is to be understood as described below:

• in the in 1 In the basic state of the electropneumatic parking brake control device 1 shown, both the first 3/2-way solenoid valve 10 and the second 2/2-way solenoid valve 12 are not energized, so that the control input 20 is always connected to the working output 28 of the relay valve 18 via the throttle element 30.

The feedback is stable and no compressed air can get from the supply connection 2 to the control input 20 of the relay valve 18 or escape from it via the vent on the first 3/2-way solenoid valve.

A pressure set at the control input 20 can preferably be locked in the blocked position by means of the second 2/2-way solenoid valve 12 .

In particular, the currently prevailing pressure at the connection 40 for the at least one spring-actuated brake cylinder and thus also its application or release position is kept constant.

If the pressure at port 40 for the at least one spring brake cylinder is to be increased in response to a corresponding parking brake signal, for example in the operating state “auxiliary brake” or “operate parking brakes with a specific brake pressure value”, then according to 2 by energizing the first 3/2-way solenoid valve 10 this can be switched to open position. As soon as the second 2/2-way solenoid valve is also switched to the through position, the applied pressure is passed on via the control line 22 to the control input 20 of the relay valve 18 .

The pressure can be passed on to the control input 20 in particular by pulsing the second 2/2-way solenoid valve 12 .

Should, however, according to a corresponding parking brake signal 3 a lower pressure at connection 40 for the at least one spring-actuated brake cylinder can be adjusted, for example in the "auxiliary brake" operating state, by switching or controlling the first 3/2-way solenoid valve to the venting position, in particular by switching or controlling without current, and the control pressure at the control input 20 is lowered by means of the second 2/2-way solenoid valve 12, preferably by pulsing.

To establish the “driving” operating state in response to a corresponding parking brake signal, the first 3/2-way solenoid valve 10 and the second 2/2-way solenoid valve are energized over a longer period of time. As a result, the control port 20 of the relay valve 18 is pressurized via the control line 22, even if initially, due to the throttle element 30, a small portion of the air routed from the valves 10, 12 to the control port 20 flows into the relay valve 18.

To establish the “parking” or “parking brakes” operating state, the second 2/2-way solenoid valve 12 can be energized for a certain period of time, in particular while the first 3/2-way solenoid valve is de-energized/controlled or controlled in the venting position.

As a result, the control connection 20 or the control line 22 and thus the relay valve 18 is vented until atmospheric pressure prevails there.

Furthermore, the electronic control device 14 can be designed in such a way that on the basis of a signal representing an actual pressure and a parking brake signal representing a value for a setpoint pressure, it carries out a setpoint/actual comparison as part of a pressure regulation and/or a pressure Performs a plausibility check and/or a determination of the reservoir pressure present at the reservoir port 2.

If, for example, according to the 1 until 3 In the exemplary embodiment shown, a pressure sensor is connected to working outlet 28 of relay valve 18 and is therefore also connected to port 40 for the at least one spring-loaded brake cylinder, so the actual pressure and from it the operating state of the at least one spring-loaded brake cylinder (released, applied or partially released or tightened) can be determined.

Furthermore, a pressure control circuit can be implemented in which the first solenoid valve device 8 in conjunction with the relay valve 18 form the actuators. If only the pressure sensor 88 is used, however, the pressure controller will only detect pressure deviations when a deviation in the working output pressure of the relay valve has already set in. This can lead to increased compressed air consumption.

If a pressure sensor 89 is connected to the control input 20 of the relay valve 18 or is arranged between the valves 10, 12, the actual pressure regulated by the solenoid valves 10, 12 can be determined very quickly, which results in high dynamics of the pressure control circuit .

In addition, the operating state of the at least one spring-loaded brake cylinder (released, applied or partially released or applied) and the actual brake pressure prevailing there can also be determined, albeit with less accuracy than when pressure sensor 88 is used, since the response behavior and hysteresis of the relay valve are make mistakes.

The same then also applies to the operating status of the trailer brakes. A particular advantage when using the pressure sensor 89 at the control input 20 or between the valves 10, 12 is that the pressure controller can regulate pressure deviations at the control input 20 so finely that they do not yet lead to a pressure deviation at the working output 28 of the relay valve 18.

If a first pressure sensor 88 is connected to the working outlet 28 and a second pressure sensor 89 is connected to the control input of the relay valve 18 or is arranged between the valves 10, 12, this also enables error detection by means of a plausibility check. For example, the actual pressure values of the first and second pressure sensors 88, 89 must be in a specific relationship to one another depending on the operating state, taking into account specific tolerances. The error detection or error monitoring can be carried out quickly, completely and in several operating states. Furthermore, there is faster pressure regulation with less compressed air consumption than if only one pressure sensor 88 is arranged at the working outlet 28 of the relay valve 18 and a more precise pressure regulation of the working outlet pressure than if only one pressure sensor 89 is arranged at the control inlet 20 of the relay valve 18 or between the valves 10, 12.

Furthermore, combining the electropneumatic parking brake control device with another electronically controlled vehicle system to form a structural unit can be advantageous, since a common electronic control device can be provided.

In particular, the combination with an air treatment system offers advantages, since the supply line to the electropneumatic parking brake control device can also be omitted here.

In summary, with the present invention, an electropneumatic parking brake control device can be provided which allows simple, efficient and rapid control or regulation of the pressure at the control input 20 of the relay valve, with the further use of a feedback line 26 from the working output 28 of the relay valve 18.

Reference List

1

brake control device

2

supply connection

4

check valve

6

supply line

8th

first solenoid valve device

10

first 3/2-way solenoid valve

12

second 2/2-way solenoid valve

14

control device

16

supply receipt

18

relay valve

20

control input

22

control line

26

feedback line

28

work exit

30

throttle element

38

working line

40

Connection for spring brake cylinder

88

first pressure sensor

89

second pressure sensor

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 102009016983 A1 [0004]
• DE 10247812 C1 [0004]
• DE 102006055570 B4 [0004]
• DE 102007061908 B4 [0005, 0009, 0010]

Claims (14)

Electropneumatic parking brake control device (1) for controlling a parking brake containing at least one spring-loaded brake cylinder, having a) a connection (40) for the at least one spring-loaded brake cylinder, b) a first solenoid valve device (8) that can be controlled by means of an electronic control device (14), c) a relay valve (18 ), the pneumatic control input (20) of which is connected on the one hand to the first solenoid valve device (8) and on the other hand to its working output (28) and to the connection (40) for the at least one spring brake cylinder, d) a supply connection (2) for at least one compressed air supply , which is connected on the one hand to the first solenoid valve device (8) and on the other hand to a supply inlet (16) of the relay valve (18), e) a feedback line (26) through which the working outlet (28) and the pneumatic control inlet (20) of the relay valve (18) can be connected to one another, thereby marked t that f) the first solenoid valve device (8) is formed by two solenoid valves (10, 12, 30), g) a first 3/2-way solenoid valve (10) as an inlet valve between the supply port (2) and the control input (20 ) of the relay valve (18) is arranged and a second 2/2-way solenoid valve (12) is arranged between the first 3/2-way solenoid valve (10) and the control input (20) of the relay valve (18), h) in the feedback line ( 26) at least one throttle element (30) is arranged in such a way that the working output and the pneumatic control input (20) of the relay valve (18) are always in fluid communication with one another. Electropneumatic parking brake control device (1) according to one of the preceding claims, characterized in that the electronic control device (14) is connected to an electrical parking brake signal connection for an electrical parking brake signal transmitter, via which parking brake signals can be fed into the electronic control device (14). Electropneumatic parking brake control device (1) according to one of the preceding claims, characterized in that the electronic control device (14) is connected to a signal connection for inputting signals from which the electronic control device (14) generates parking brake signals. Electropneumatic parking brake control device (1) according to one of the preceding claims, characterized in that the first 3/2-way solenoid valve (10) has a currentless venting position and an energized open position and the second 2/2-way solenoid valve (12) has a currentless blocking position and an energized open position own. Electropneumatic parking brake control device (1) according to one of the preceding claims, characterized in that when a steering or a generation of a state "driving" representing parking brake signal in the electronic control device (14) or in the electronic control device (14) the first 3/2- Directional solenoid valve (10) is controlled by the electronic control device (14) in the open position and first the second 2/2-way solenoid valve (12) in the open position and then in the blocked position. Electropneumatic parking brake control device (1) according to one of the preceding claims, characterized in that when a parking brake signal representing an "actuate parking brake with a specific brake pressure value" state is input or generated in the electronic control device (14) or in the electronic control device (14), this controls the first 3/2-way solenoid valve (10) and/or the second 2/2-way solenoid valve (12) depending on the respective brake pressure value in the blocking position or in the venting position or in the open position. Electropneumatic parking brake control device (1). claim 6 , characterized in that the electronic control device (14) controls the first 3/2-way solenoid valve (10) and/or the second 2/2-way solenoid valve (12) alternately or in pulses in the blocking position or in the venting position and in the open position. Electropneumatic parking brake control device (1) according to one of the preceding claims, characterized in that when a parking brake signal representing a "parking brakes" state is fed into or generated in the electronic control device (14) or in the control device (14), this the first 3/2-way solenoid valve (10) in the venting position and first controls the second 2/2-way solenoid valve (12) in the open position and then the second 2/2-way solenoid valve (12) in the closed position. Electropneumatic parking brake control device according to one of the preceding claims, characterized in that it is provided for a towing vehicle/trailer combination and has a connection for a trailer control valve, which can be connected to the connection (40) for the at least one spring brake cylinder. Electropneumatic parking brake control device according to one of the preceding claims, characterized in that the supply connection (2) is protected by a check valve (4). Electropneumatic parking brake control device claim 10 , characterized in that at least the relay valve (18), the first solenoid valve device (8), the check valve (4), the at least one throttle element (30), the electronic control device (14) and the supply connection (2), the connection (40 ) are formed for the at least one spring-actuated brake cylinder and the parking brake signal connection in one structural unit (92). Electropneumatic parking brake control device claim 10 , characterized in that at least the relay valve (18), the first solenoid valve device (8), the electronic control device (14), the at least one throttle element (30) and the supply connection (2), the connection (40) for the at least one spring brake cylinder , the connection for the trailer control valve and the parking brake signal connection are formed in a structural unit (92), at least the check valve (4) and at least part of the feedback line (26) being arranged outside the structural unit (92). Brake system of a vehicle, containing an electropneumatic parking brake control device (1) according to at least one of the preceding claims. Vehicle with an electropneumatic parking brake control device (1) or a brake system according to at least one of the preceding claims.

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