EP2160310A1

EP2160310A1 - Combined braking system, particularly for motor vehicles

Info

Publication number: EP2160310A1
Application number: EP08774121A
Authority: EP
Inventors: Andreas Heise; Burkhard Warmbier-Leiding; Ralf Hartmann
Original assignee: Continental Teves AG and Co OHG
Current assignee: Continental Teves AG and Co OHG
Priority date: 2007-06-19
Filing date: 2008-06-18
Publication date: 2010-03-10
Also published as: CN101687498A; KR101512869B1; US20100241330A1; KR20100035705A; DE102008024180A1; CN101687498B; WO2008155341A1; US8838354B2

Abstract

The invention relates to a combined braking system, comprising hydraulic brakes (7, 8) associated with a vehicle axle and brakes (8, 9) actuatable by means of electromechanical actuators (11, 12) associated with a different vehicle axis, each electronic control unit (19, 20) associated with the electromechanical actuators (11, 12) having at least two high-speed busses (24, 26 and 25, 26), of which one (24) is connected directly to a further electronic control unit (18) and the other (26) is directly or indirectly connected to an electronic or electrohydraulic control unit (5) associated with the hydraulic brakes (7, 8).

Description

Combined brake system, especially for motor vehicles

The invention relates to a combined brake system, in particular for motor vehicles, associated with a first vehicle axle, electromechanically or hydraulically actuated wheel brakes and associated with a second vehicle axle actuated by electromechanical actuators wheel brakes, wherein the second vehicle axle associated, electromechanically actuated wheel brakes in accordance with one of the the first vehicle axle associated wheel brakes applied braking request or derived therefrom data via a vehicle bus (eg CAN) and / or in accordance with output signals of a redundant pedal travel sensor, which determines the actuation of a brake pedal, actuated, and wherein some or all e electromechanically actuable wheel brakes comprise a parking brake device, which can be activated by means of a control element, with one of the first vehicle axle

ordered e.g. electrohydraulic control unit, each with one of the electromechanical actuators of the second vehicle axle associated electronic control unit, with wheel speed sensors whose signals are supplied to the electro-hydraulic control unit and / or the electronic control units, and a communication bus between the electrohydraulic control unit and the electronic control units.

Such a combined brake system is known from international patent application WO 002007014952 Al. A disadvantage is to be considered in the prior art brake system the fact that if one of the electro-hydraulic control unit to an electromechanical actuator associated electronic control and regulating unit leading communication bus is defective or disturbed, the system goes into a fallback with limited functionality or even completely fails.

It is therefore an object of the present invention to increase the availability of the brake functionality for electrical errors in a combined brake system of the type mentioned. Furthermore, the robustness by using standard bus systems, such. B. CAN, be increased. In addition, the use of special and control lines or buses and special parking brake controls should be avoided. A further object of the invention is to reduce the number of supply and control lines on the electromechanical actuator and to ensure full diagnosability at an electro-mechanical actuator. to ensure mechanical actuator even with a bus error.

The above-listed tasks are inventively achieved in that each of the electromechanical actuators associated electronic control unit has at least two high-speed buses, one of which directly with another electronic control unit and the other directly or indirectly with the electro-hydraulic control and Control unit is connected.

In an advantageous development of the subject invention, the pedal travel sensor is connected on two separate paths indirectly or directly connected to the electromechanical actuators associated electronic control and regulation units. The separate paths are preferably formed by buses or signal lines. The distributed to the individual control units control pedal position information, which need not be redundant as a single, can be processed by communication of the control units with each other with respect to the information available in each case to a redundant (secure) information, which in turn acts autonomously the control devices, for example, methods of brake pads or applying the brake pads, or even perform brake operations are used.

A further increase in the operational safety of the brake system according to the invention is achieved in another embodiment variant of the invention in that at least one of the high-speed buses is used as a point-to-point connection. Point connection is performed, although the bus system is usually designed for use with many partners.

In a particularly preferred embodiment of the subject invention, it is provided that the operating element for actuating the parking brake is connected directly to an electronic control and regulating unit. The electronic control unit is the electro-hydraulic control unit or another control and regulating unit, such as a motor control and regulating unit or a chassis controller. The connection to the electrohydraulic control unit makes it possible, without routing the signals via other partners, etc., directly via the e.g. hydraulically operated wheels immediately initiate allrädrig initiated dynamic deceleration. A parking brake switch coupled in via another control unit allows the parking brake to be operated even in the event of complete failure of the control unit (for example the electrohydraulic control unit).

A further advantageous embodiment of the subject of the invention is that in the event of a fault of a high-speed bus, all system-relevant data (eg braking request) are automatically or indirectly fed directly via another high-speed bus to the electronic control unit connected thereto. This important part of the design makes it possible to ensure the full functionality of the system (braking, parking, etc.) even in the event of a "big mistake", such as the failure of a high-speed bus and not to put any restrictions on the performance. An indication, eg by warning lamp or reference to workshop service, however, makes sense.

In another advantageous embodiment of the subject invention is provided that in case of failure of an electromechanical actuator associated control and regulation unit or their electrical connection with malfunctioning connected to one or more signal and / or supply lines, the rest of the system is still fully available and parking brake - As well as service brake function can be used. In case of failure of a wheel unit or the supply of these, the remainder of the system can still operate completely self-sufficient, i. Dynamic deceleration can then be controlled via two to three vehicle wheels. Shutdown and release the parking brake can continue to be done on request with a Radaktuator. A restriction by the parking brake with only one wheel is of course present in the hill hold force.

A particularly reliable working variant provides that the electrical supply of one or more electromechanical actuators individually or jointly by the control of one or more electrical switches by a logical OR operation of a signal supplied by the electro-hydraulic control unit and an ignition signal or a is carried by a further electronic control unit signal supplied. A further increase in the reliability of the brake system according to the invention is achieved in one embodiment of the subject invention in that all high-speed buses are used in normal operation continuously for data transfer and thus monitored.

In a particularly preferred embodiment of the invention, it is provided that in case of failure of the electro-hydraulic control and regulation unit, in which a detection of the braking request by the electro-hydraulic control and regulation unit or their transmission to the electronic control and regulating units, the pedal travel sensor information is used for the activation of electromechanical actuators. If the electrohydraulic control unit has failed, the hydraulically operated wheels are still used hydraulically, ie usually without electronic control.

The electromechanically braked wheels no longer receive all the information and can still perform a braking function in a fallback level. The brake function can be done because of the twice supplied pedal sensor and possibly additional wheel speed information to the electromechanical actuators.

Another advantageous embodiment provides that the electromechanical actuators associated electronic control and regulation units communicate the braking request with each other and / or plausibility. Equal and plausibility check as well as possibility to build up the brake force etc. equally. (Sentence construction ???) In a particularly reliable braking system according to the invention, finally, the electronic control and regulating units assigned to the electromechanical actuators are each designed to be intrinsically safe and thereby perform the braking request and / or the parking brake request with a reliable single or redundant command. The intrinsic safety, ie own fault detection and redundant own Abschaltpfade for safety-critical functions, allows it without intervention, eg hardwire release line, a second or third control unit to perform functions such as braking or deceleration.

In another advantageous embodiment of the invention, a plurality of commands of at least one electronic control unit, e.g. Electro-hydraulic control unit on at least two high-speed buses (such as CAN), that is redundantly sent, and the data are indirectly or directly supplied to the different ways, so redundant, of the electronic control units of the electromechanical actuators. (Please, by the measures reached, supplement beneficial effects!)

A further increase in the operational safety of the brake system according to the invention is achieved according to an embodiment of the subject invention in that at least one electronic control unit of an electromechanical actuator using the data of the other data path in case of failure of the data of one data path. The data transmission on the high-speed buses can be considered safe by suitable monitoring mechanisms.

In a particularly preferred embodiment of the invention, it is provided that data which reach an electronic control unit of an electromechanical actuator, but are not intended for this actuator, on the other high-speed bus of the electromechanical actuator, z, B. to the actual receiver , to be passed on.

The invention will be explained below in connection with six embodiments with reference to the accompanying drawings. In the drawing show:

1 shows a circuit diagram of a first embodiment of the brake system according to the invention with hydraulically and electromechanically actuated brakes.

FIG. 2 shows a second embodiment of the brake system according to the invention in a simplified representation compared with FIG. 1; FIG.

3 shows a circuit diagram of a third embodiment of the brake system according to the invention with hydraulically and electromechanically actuated brakes;

4 shows a circuit diagram of a fourth embodiment of the brake system according to the invention in a representation corresponding to FIG. 3; 5 shows a circuit diagram of a fifth embodiment of the brake system according to the invention in a representation corresponding to FIG. 4; and

Fig. 6 is a circuit diagram of a sixth embodiment of the brake system according to the invention in a Fig. 5 corresponding representation.

The first embodiment of the motor vehicle brake system according to the invention shown in FIG. 1 essentially has an actuating unit 1 which can be actuated by means of a brake pedal 2. The actuation unit 1 in turn consists of a pneumatic brake booster or a vacuum brake booster 3 and a brake master cylinder 4 connected downstream of the vacuum brake booster 3, to which an electro-hydraulic control unit 5 is connected by means of a hydraulic line 6. To the electro-hydraulic control and regulation unit 5 are hydraulically actuated wheel brakes 7, 8 are connected by means of hydraulic lines 15, 16, which are assigned in the example shown a first vehicle axle or front axle.

As FIG. 1 further shows, wheel brakes 9, 10 are assigned to a second vehicle axle or the rear axle, the actuation of which is effected by electromechanical actuators 11, 12 in accordance with the hydraulic pressure applied in the hydraulically actuated wheel brakes 7, 8. The mentioned hydraulic pressure is determined by means of pressure sensors, not shown, which are integrated in the electro-hydraulic control unit 5. Based on this pressure value, the electromechanical nisch operable wheel brakes 9, 10 driven, ie, taking into account a braking force distribution function between the front and rear axles Zuspannkraft the wheel brakes 9, 10 is set. In addition, the electromechanically actuated brakes 9, 10 can be controlled in accordance with the actuation path of the brake pedal 2, ie in accordance with the driver deceleration request. For this purpose, the actuating travel of the brake pedal 2 is determined by means of a preferably redundantly designed pedal travel sensor 22. The control of the rear axle associated with wheel brakes 9, 10 is decentralized by an electronic control and regulation unit 19, 20 made.

As is indicated only schematically in Fig. 1, the brake system shown is equipped with a parking brake functionality. For this purpose, the electromechanically actuable wheel brakes 9, 10 have parking brake devices, not shown, with which the wheel brakes 9, 10 can be locked in the tightened state. The parking brake devices can be controlled by means of a control element 14, which is designed as a button and the three switch positions for the commands "clamping", "neutral" and "release" has.

The present invention now provides that the output signals of the pedal travel sensor 22 via a signal line 17 to another electronic control and regulation unit 18 is supplied, which may be formed for example by a chassis controller. A first high-speed bus 23 forms a direct connection between the aforementioned electrohydraulic control unit (HECU) 5 and the further electronic control unit. and control unit 18, which is directly connected by means of another high-speed bus 24 with the electronic control unit 19 of the electromechanical actuator 11. A second signal line 28 is used for signal transmission between the parking brake control element 14 and the electro-hydraulic control unit (HECU) 5, which is directly connected by means of a third Hochgeschwindigkeitsbusses 25 with the electronic control unit 20 of the electromechanical actuator 12, so that the Output signals of the parking brake control element 14 of said electronic control and regulation unit 20 are supplied. A fourth high-speed bus 26 forms a direct connection between the electronic control and regulation units 20 and 19 of the electromechanical actuators 12 and 11. The dashed line 28 represents an optionally existing line to possibly further control and regulating units all power supply terminals of the elements shown in Fig. 1 denotes. From the illustration in Fig. 1 it can be seen that the high-speed buses 23 and 24 form a first indirect connection of the HECU 5 with the electronic control unit 19 of the electromechanical actuator 11, while a second, indirect connection between said elements through the high-speed buses 25 and 26 is formed.

In the second embodiment of the combined brake system according to the invention shown in FIG. 2, the actuating unit 1 is formed by a brake pedal 102 with a pedal travel sensor 122 assigned to it. A first high-speed bus 123 connects the actuator unit 1 with the HECU 5, while a second high speed bus 124 connects the actuator unit 1 to the electronic control unit 19 of the electromechanical actuator 11. To the mentioned in connection with FIG. 1 line 27, for example, a sensor cluster 30 and another, freely selectable electronic control unit 31 are connected. To the HECU 5 is another communication interface, z. B. a vehicle bus 32 is connected. Otherwise, the circuit shown in Fig. 2 corresponds to the circuit of FIG. 1, wherein corresponding components are provided with the same reference numerals.

The embodiment of the actuation unit 1 of the third embodiment shown in FIG. 3 corresponds to that of the actuation unit 1 according to FIG. 2. The signal transmission between the pedal travel sensor 122 and the electronic control units 19 and 20 of the electromechanical actuators 11, 12 serve signal lines 33, 34 , wherein the HECU 5 is directly connected to the electronic control unit 19 by means of another high-speed bus 35. The circuit diagrams shown both in FIG. 2 and in FIG. 3 show that both variants shown can only operate in the "brake-by-wire" mode.

The construction of the fourth embodiment of the subject invention shown in Fig. 4 corresponds largely to that of the embodiment of FIG. 3. The difference is that at the HECU 5 with the electronic control unit 19 directly connecting high-speed bus 35 both in connection with Fig. 1 mentioned electronic control unit 18 as well the optionally existing line 27 are connected to the components 30, 31 shown in FIG. The output signals of the parking brake control element 14 are supplied via a signal line 36 of the electronic control unit 18 and from there via the high-speed buses 35 and 26 to the electronic control units 19 and 20 of the electromechanical actuators 11, 12 connected.

The construction of the fifth embodiment of the subject invention shown in Fig. 5 largely corresponds to that of the embodiment of FIG. 2. The difference is that the power supply of the electromechanical actuators 11, 12 by means of a switching relay 38, 39 is switched. The switching relays 38, 39 are driven by output signals of two logical OR circuits 40, 41, the inputs of which are supplied by the HECU 5 generated signals 42 and signals IGN, which are generated for example by the vehicle ignition.

In the sixth embodiment of the subject invention shown in Fig. 6, a further electronic control and regulating unit 18 is connected in the signal path (23, 24) between the HECU 5 and the electromechanical actuator 11 associated electronic control unit 19, for example, in connection was mentioned with Fig. 1 and the signal generated via the signal line 17 from the brake pedal sensor 122 Bremswunschsignale be supplied. In the Fig. 5 corresponding switched power supply of the electromechanical actuators 11, 12 are the inputs of the two switching relays 38, 39 associated with OR circuits 40, 41 instead of the ignition signals IGN Control signals 43 supplied, which are generated by the further electronic control unit 18.

Claims

Claims:

1. Combined brake system, in particular for motor vehicles, associated with a first vehicle axle, electromechanically or hydraulically actuated wheel brakes and associated with a second vehicle axle actuated by electromechanical actuators wheel brakes, wherein the second vehicle axle associated, electromechanically actuated wheel brakes in accordance with one of the first Vehicle axle associated with the wheel brakes predetermined braking request or derived therefrom data via a vehicle bus and / or in accordance with output signals of a redundantly running pedal travel sensor or driver brake wish detection sensor, which determines the actuation of a brake pedal or Bremsenbedienelements actuated, and wherein the at least two electromechanically actuated wheel brakes a Parking brake device comprise, which can be controlled by means of a parking brake control element, with one of the first vehicle axle associated electronis chen or electro-hydraulic control unit, each with a the electromechanical actuators of the second vehicle axle associated electronic control unit, with wheel speed sensors whose signals the electronic or electro-hydraulic control unit and / or the electronic control units electromechanical actuators, as well as with a communication bus between the electrohydraulic control unit and the electronic control and regulating unit. characterized in that each electronic control unit (19, 20) associated with the electromechanical actuators (11, 12) has at least two high-speed buses (24, 26 and 25, 26), one of which (24) directly with another electronic control unit (18) and the other (26) are directly or indirectly connected to the electronic or electro-hydraulic control unit (5).

2. Combined brake system according to claim 1, characterized in that the pedal travel sensor (22, 122) on two separate paths directly or indirectly with the electromechanical actuators

(11, 12) associated electronic control and regulating units (19, 20) is connected.

3. Combined brake system according to claim 2, characterized in that the separate paths by buses (24, 26) or signal lines (33, 34) are formed.

4. Combined brake system according to one of claims 1 to

3, characterized in that at least one of the high-speed buses (23, 24, 25, 26) is designed as a point-to-point connection.

5. Combined brake system according to one of claims 1 to

4 characterized in that the operating element (14) for actuating the parking brake directly to an electronic control unit (5, 18) ange- release i st.

6. Combined brake system according to claim 5, characterized in that the electronic control unit is the electro-hydraulic control unit (5).

7. Combined brake system according to claim 5, characterized in that the electronic control unit is another control and regulating unit (18).

8. Combined brake system according to one of claims 1 to

7 characterized in that in case of failure of a high-speed bus (23 - 26) all system-relevant data such as a braking request automatically via another high-speed bus (23 - 26) indirectly or directly the electronic control unit connected thereto (19, 20) are supplied or that they are used there anyway permanently with launched data in the disturbance.

9. Combined brake system according to one of claims 1 to

8, characterized in that in case of failure of an electromechanical actuator (11, 12) associated control and regulating unit (19, 20) or their electrical connection with malfunction connected to one or more signal and / or supply lines, the rest system still fully available and is suitable for parking brake and service brake functions. can be used.

10. Combined brake system according to one of claims 1 to

9 characterized in that the electrical supply of one or more electromechanical Aktuato- ren (11, 12) individually or jointly by the control of one or more electrical switches (38, 39) by a logical OR operation (40, 41) one of electro-hydraulic control and regulating unit (5) supplied signal (42) and an ignition signal (IGN) or of a further electronic control unit (18) supplied signal (43).

11. Combined brake system according to one of claims 1 to

10 characterized in that all high-speed buses (23 - 26) are used in normal operation continuously for data transfer and thus monitored.

12. Combined brake system according to one of claims 1 to

11 characterized in that in case of failure of the electro-hydraulic control unit (5), in which a detection of the braking request by the electrohydraulic control unit (5) or their Ü bermittlung to the electronic control and regulation units (19 , 20) is no longer safely possible, the pedal travel sensor information for the activation of the e- lektromechanischen actuators (11, 12) is used.

13. Combined brake system according to claim 12, characterized in that the electromechanical actuators (11, 12) associated electronic control and Control units (19, 20) communicate the braking request with each other and / or plausibility.

14. Combined brake system according to claim 12 or 13, characterized in that the electromechanical actuators (11, 12) associated with electronic control and regulation units (19, 20) are each designed intrinsically safe and thereby with safe single or redundant command the braking request and / or execute the parking brake request.

15. Combined brake system according to claim 1 to 12, characterized in that a plurality of commands at least one electronic control unit (5, 18, 19, 20), for. electro-hydraulic control unit (5) are sent redundantly on at least two Hochgeschwindigkeitsbussen and the data so indirectly or directly on the different ways so the redundant electronic control units (19, 20) of the electromechanical actuators (11, 12) are supplied ,

16. Combined brake system according to claim 15, characterized in that at least one electronic control unit (19, 20) of an electromechanical actuator (11, 12) in case of failure of the data of one data path uses the data of the other data path.

17. Combined brake system according to claim 1 to 15, characterized in that the data transmission on the Hochgeschwindigkeitsbussen (23 - 26) by suitable Monitoring mechanisms can be considered safe.

18. Combined brake system according to claim 1 to 15, characterized in that data which reach an electronic control unit (19, 20) of an electromechanical actuator (11, 12), but are not intended for this actuator, on the other High-speed bus (?) Of the electromechanical actuator (11, 12) are passed, for example to the actual receiver.