Fail-Safe Parking Brake for Motor Vehicles

• US 20130282249A1
• Filed: 10/17/2011
• Published: 10/24/2013
• Est. Priority Date: 10/18/2010
• Status: Active Grant

• Current Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Original Assignee: Continental Teves AG & Company HG (Continental AG)
• Inventors: Heise, Andreas, Schade, Kai
• Granted Patent: US 9,428,159 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60T 13/588 both fluid and mechanical assistance or drive
• CPC Class Codes: B60T 13/741 acting on an ultimate actuator
• CPC Class Codes: B60T 13/745 acting on a hydraulic system, e.g. a master cylinder
• CPC Class Codes: B60T 13/746 and mechanical transmission of the braking action
• CPC Class Codes: B60T 13/748 acting on electro-magnetic brakes combined with fluid-pressure brake systems B60T13/667
• CPC Class Codes: B60T 17/221 Procedure or apparatus for checking or keeping in a correct functioning condition of brake systems hydraulic pressure systems in general F15B19/00, F15B21/04; testing structures or apparatus G01M
• CPC Class Codes: B60T 2270/413 Plausibility monitoring, cross check, redundancy
• CPC Class Codes: B60T 7/042 by electrical means, e.g. using travel or force sensors
• CPC Class Codes: B60T 7/045 with locking and release means, e.g. providing parking brake application
• CPC Class Codes: B60T 7/107 with electrical power assistance
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00

Abstract

The invention relates to an electronic controller for a brake system of a motor vehicle, which comprises at least one interface to a control element, in particular a parking brake control switch, and at least two drive circuits for electric actuators, in particular electric parking brake actuators. According to the invention, the electronic controller comprises two or a plurality of independent arithmetic units, which are directly connected to each other via a data bus. A motor vehicle equipped with a controller or brake system according to the invention requires no transmission lock in an automatic gearbox.

Claims

1. An electronic controller for a brake system of a motor vehicle, which comprises at least one interface to a control element, in particular a parking brake control switch, and at least two drive circuits for electric actuators, in particular electric parking brake actuators, characterized by two or a plurality of independent arithmetic units, which are directly connected to each other by means of a data bus.

2. The electronic controller as claimed in claim 1, characterized in that at least two independent arithmetic units are each associated with a power supply, which preferably comprises at least one voltage converter and at least one fuse, in particular in each case a battery and/or a generator.

3. The electronic controller as claimed in at least one of the preceding claims, characterized in that the independent arithmetic units and the data bus are integrated on a substrate, in particular a silicon chip.

4. The electronic controller as claimed in at least one of the preceding claims, characterized in that at least two of the independent arithmetic units are implemented at least partly in redundant form.

5. The electronic controller as claimed in claim 4, characterized in that at least one of the arithmetic units, in particular two, is in the form of a redundant core microcontroller, in particular with two processor cores working in lockstep mode.

6. The electronic controller as claimed in claim 4 or 5, characterized in that at least one of the arithmetic units is in the form of a microcontroller with asynchronous redundancy, wherein two processor cores at least partly access common devices, in particular a volatile or non-volatile memory protected with parity checking.

7. The electronic controller as claimed in at least one of the claims 4 through 6, characterized in that at least one of the arithmetic units is in the form of a microcontroller protected by a watchdog counter, which runs two processes that monitor each other.

8. The electronic controller as claimed in at least one of the preceding claims, characterized in that at least two independent drive circuits for electric parking brake actuators, in particular pulse width modulation circuits and bridge circuits, are provided, each of which is associated with a power supply, which preferably comprises at least one voltage converter and at least one fuse, in particular in each case a battery and/or a generator.

9. The electronic controller as claimed in at least one of the preceding claims, characterized in that at least one of the arithmetic units comprises means for error recognition, which outputs a signal on the data bus and/or to an error interface when a fault occurs.

10. The electronic controller as claimed in claim 9, characterized in that a first arithmetic unit is connected to two drive circuits for electric parking brake actuators, in particular bridge circuits, wherein a switch is disposed in the connection between the first arithmetic unit and at least one drive circuit, which is connected to a second arithmetic unit and an error interface of the first arithmetic unit.

11. The electronic controller as claimed in claim 9, characterized in that a first arithmetic unit is connected to a first drive circuit for electric parking brake actuators and a second arithmetic unit is connected to a second drive circuit for electric parking brake actuators.

12. The electronic controller as claimed in claim 9, characterized in that a first switch is disposed in the connection between a first arithmetic unit and a first drive circuit, and a second switch is disposed in the connection between a second arithmetic unit and a second drive circuit, wherein the first switch is connected to the second arithmetic unit and an error interface of the first arithmetic unit, and the second switch is connected to the first arithmetic unit and an error interface of the second arithmetic unit.

13. The electronic controller as claimed in at least one of the preceding claims, characterized by at least one acceleration sensor, at least one yaw rate sensor and at least one interface for wheel revolution rate sensors.

14. The electronic controller as claimed in at least one of the preceding claims, characterized by at least one interface to an external data bus, in particular a CAN or FlexRay bus.

15. The electronic controller as claimed in at least one of the preceding claims, characterized by at least one electrically controllable hydraulic valve, at least one electric hydraulic pump and at least one interface for pressure sensors.

16. A brake system for a motor vehicle, comprising a service brake on all wheels and electric parking brake actuators on at least two wheels, characterized by an electronic controller as claimed in at least one of the preceding claims, which is connected to the electric parking brake actuators.

17. The brake system as claimed in claim 16, characterized in that the service brake comprises at least one hydraulic brake circuit and the electronic controller provides traction control and/or driving dynamics control.

18. The brake system as claimed in claim 16 or 17, characterized in that the wheels of at least one axle comprise electromechanical friction brakes as a service brake.

19. A motor vehicle, characterized by a brake system as claimed in at least one of the claims 16 through 18.

20. The motor vehicle as claimed in claim 19, characterized in that an internal combustion engine and/or an electric motor is connected to the wheels of at least one axle via an automatic gearbox without a transmission lock.