Method and system for controlling brake equipment which can be activated when a motor vehicle is stationary

• US 20030214185A1
• Filed: 06/18/2003
• Published: 11/20/2003
• Est. Priority Date: 12/18/2000
• Status: Active Grant

• Current Assignee: Lucas Automotive GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: Lucas Automotive GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Kinder, Ralf, Leiter, Ralf, Endres, Franz-Josef, Maack, Lorenz, Klapper, Gerhard, Shokoufandeh, Reza, Sons, Andreas
• Granted Patent: US 7,401,872 B2
• Time in Patent Office: Days
• US Class Current: 303/192
• CPC Class Codes: B60T 11/103 in combination with other control devices conjoint control of brake system and at least another sub-unit B60W10/188
• CPC Class Codes: B60T 2201/06 Hill holder; Start aid systems on inclined road
• CPC Class Codes: B60T 7/122 for locking of reverse movement

Abstract

The present invention provides a method and a system for controlling a braking equipment of a motor vehicle in order to activate the braking equipment at a standstill of the motor vehicle such that braking forces are built up which are necessary to keep the motor vehicle in a state of standstill. To this end it is established on the basis of vehicle movements whether the vehicle is at a standstill. If vehicle movements are detected that cannot occur during driving modes of the motor vehicle, the motor vehicle is in a state of standstill. Subsequently, the braking equipment, and in particular a holding brake mechanism included in the braking equipment, are activated. In order to provide braking forces keeping the motor vehicle at a standstill also when it is on a slope, the braking equipment, and in particular the holding brake mechanism, are controlled in response of the vehicle inclination present in the state of standstill.

Claims

1. A method for controlling a braking equipment adapted to be activated at a state of standstill of a motor vehicle independently of an actuation of the braking equipment (6, 10), comprising the following steps:

establishing an operating state of a motor vehicle in which the motor vehicle is in the state of standstill and

controlling a braking equipment (6, 10) of the motor vehicle so that, independently of an actuation of the braking equipment (6, 10) by a vehicle driver, braking forces are built up that hold the motor vehicle in a state of standstill;

characterized in that

in order to establish the state of standstill of the motor vehicle

vehicle movements are detected and

it is checked whether the detected vehicle movements are vehicle movements that cannot occur during operating states in which the motor vehicle is in a driving state.

2. The method according to claim 1, in which for detecting the state of standstill of the motor vehicle vehicle movements in the form of

dynamic movements,

inclinations of the motor vehicle about its transverse and/or longitudinal axis or

changes in the inclination of the motor vehicle about its transverse and/or longitudinal axis

are detected.

3. The method according to claim 1 or 2, in which

the braking equipment (6, 10) is controlled to build up the braking forces necessary for the state of standstill if, upon reaching the state of standstill, the brake pressure generated by a service braking device (10) is equal to or larger than a preset reference brake pressure (pB_ref).

4. The method according to claim 3, in which

the braking equipment (6, 10) is controlled to build up the braking forces necessary for the state of standstill when the brake pressure generated by the service braking device (10) is present for a predetermined period of time (Bt).

5. The method according to one of the preceding claims, in which

a holding brake mechanism (6) is activated to build up the braking forces necessary for the state of standstill during the control of the braking equipment.

6. The method according to one of the preceding claims, in which

the braking equipment (6, 10) is controlled after a predetermined period of time after reaching the state of standstill to build up the braking forces necessary for the state of standstill.

7. The method according to one of the preceding claims, in which

the braking equipment (6, 10) is controlled in such a manner to build up the braking forces necessary for the state of standstill that the braking forces correspond to the braking forces available when reaching the state of standstill, and/or to braking forces which are detected in response to an inclination of the motor vehicle in the state of standstill and/or the vehicle weight, and/or correspond to braking forces that are elevated at a predetermined rate with respect to the braking forces available when reaching the state of standstill, and/or that clamping forces are generated which have a predetermined ratio relative to maximally possible braking forces.

8. The method according to one of the preceding claims, in which

a service braking device (10) is activated while controlling the braking equipment (6, 10) to build up the braking forces necessary for the state of standstill.

9. The method according to claim 8, in which

the service braking device (10) is activated for a specific period of time.

10. The method according to claim 8 or 9, in which

a holding brake mechanism (6) is activated after a predetermined period of time after the activation of the service braking device (10).

11. The method according to claim 10, in which

the service braking device (10) is deactivated after a predetermined period of time after the activation of the holding brake mechanism (6).

12. The method according to claim 11, in which

the holding brake mechanism (6) is deactivated for a predetermined period of time after the deactivation of the service braking device (10) in order to detect parameters characterizing braking forces made available by the holding brake mechanism (6).

13. A system for controlling a braking equipment adapted to be activated in the state of standstill of a motor vehicle, comprising:

a control unit (2) and

detection means (8, 12, 16, 18, 20, 22, 24, 26) for detecting parameters characterizing current operating states of the motor vehicle, and interfaces (4, 14) for controlling a braking equipment (66, 10), with the control unit (2) being adapted to be operated according to one of the methods of one of claims 1 to 12.

14. A computer program product having

program code portions for performing the steps according to one of claims 1 to 12.

15. The computer program product according to claim 14,

stored on a computer readable recording medium or a computer readable recording device.