Technique for determining an actuating force applied to a vehicle brake that can be actuated hydraulically and mechanically

Patent metadata

Field	Value
Publication number	US-9457774-B2
Application number	US-201214116351-A
Country	US
Kind code	B2
Filing date	Mar 2, 2012
Priority date	May 10, 2011
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

A technique for determining an actuating force applied to a vehicle brake is described, wherein the vehicle brake is equipped with an electromechanical brake actuator, and wherein a first actuating-force component is generated mechanically by actuating the electromechanical brake actuator and a second actuating-force component is generated hydraulically by actuating a hydraulic pressure source. A method aspect comprises the steps of detecting a first parameter relative to the electromechanical brake actuator and indicating the first actuating-force component, determining a second parameter indicating the second actuating-force component from a progression of the detected first parameter, and determining the actuating force applied to the vehicle brake from the first and the second parameters.

First claim

The invention claimed is:

1. A method for determining an actuating force applied to a vehicle brake, wherein the vehicle brake is equipped with an electromechanical brake actuator, comprising the following steps:
mechanically generating a of actuating-force component by actuation of the electromechanical brake actuator;
hydraulically generating a second actuating-force component by actuation of a hydraulic pressure source;
detecting a first parameter related to the electromechanical brake actuator and indicating the first actuating force component;
determining a second parameter indicating the second actuating force component from a progression of the detected first parameter, wherein the second parameter is determined from a temporal progression of electrical current consumption; and
determining the actuating force applied to the vehicle brake from the first and the second parameters.

2. The method according to claim 1 , wherein the first parameter is detected during the actuation of the electromechanical brake actuator and corresponds to the electrical current consumption of an electric motor assigned to the electromechanical brake actuator.

3. The method according to claim 2 , wherein the second parameter indicates an idling phase of the electric motor.

4. The method according to claim 3 , wherein the second parameter corresponds to a duration of the idling phase of the motor.

5. The method according to claim 3 , wherein the second parameter corresponds to an integrated motor speed during the idling phase of the motor.

6. The method according to claim 1 , wherein the second actuating-force component is determined from the second parameter and from a brake stiffness.

7. The method according to claim 1 , wherein the first actuating-force component and the second actuating-force component are generated during one or more actuation phases.

8. The method according to claim 7 , wherein during at least one actuation phase the electromechanical brake actuator and the hydraulic pressure source are actuated simultaneously.

9. The method according to claim 8 , wherein the force component generated in the case of simultaneous actuation is generated in approximately equal parts by the electromechanical brake actuator and the hydraulic pressure source.

10. The method according to claim 1 , wherein the first actuating-force component and the second actuating-force component are generated in three actuation phases, wherein during the first actuation phase the electromechanical brake actuator is actuated, during the second actuation phase the hydraulic pressure source is actuated, and during the third actuation phase the electromechanical brake actuator and the hydraulic pressure source are actuated simultaneously.

11. The method according to claim 10 , wherein the actuating force applied during the first actuating procedure amounts to more than 60% of the actuating force that is capable of being provided maximally by the electromechanical brake actuator.

12. The method according to claim 1 , wherein the second actuating force component is additionally determined from a current consumption, detected during the actuation of the hydraulic pressure source, of an electric motor assigned to the hydraulic pressure source.

13. The method according to claim 12 , wherein for the purpose of checking plausibility, the second actuating-force component determined from the current consumption of the electric motor assigned to the hydraulic pressure source is compared with the second actuating-force component determined from the second parameter.

14. The method according to claim 1 , wherein the method for determining the actuating force is carried out within the scope of a parking-brake procedure.

15. The method according to claim 1 , wherein the method is implemented by a computer-program product with program code when the computer-program product is executed on a computer device.

16. The method according to claim 15 , wherein the computer program product has been stored on a computer-readable recording medium.

17. The method according to claim 1 , wherein the first parameter is detected at the vehicle brake.

18. An apparatus for determining an actuating force applied to a vehicle brake, wherein the vehicle brake is equipped with an electromechanical brake actuator, the apparatus including the following components;
a first actuating-force component mechanically generated by actuation of the electromechanical brake actuator;
a second actuating-force component hydraulically generated by actuation of a hydraulic pressure source;
a device for detecting a first parameter related to the electromechanical brake actuator and indicating the first actuating-force component;
a device for determining a second parameter indicating the second actuating-force component from the progression of the detected first parameter, wherein the second parameter is determined from a temporal progression of electrical current consumption; and
a device for determining the actuating force applied to the vehicle brake from the first and second parameters.

19. The apparatus according to claim 18 , further including a comparator for comparing the actuating-force component that is capable of being determined from the second parameter with the second actuating-force component determined from a current consumption of the hydraulic pressure source.

20. The apparatus according to claim 18 , wherein the first parameter is detected at the vehicle brake.

21. A motor-vehicle braking system including an electromechanical brake actuator, a hydraulic circuit with hydraulic pressure source, a wheel brake coupled with the electromechanical brake actuator and with the hydraulic pressure source, and an apparatus for determining an actuating force applied to a vehicle brake, wherein the vehicle brake is equipped with an electromechanical brake actuator, the apparatus including the following components:
a first actuating-force component mechanically generated by actuation of the electromechanical brake actuator;
a second actuating-force component hydraulically generated by actuation of hydraulic pressure source;
a device for detecting a first parameter related to the electromechanical brake actuator and indicating the first actuating-force component;
a device for determining a second parameter indicating the second actuating-force component from the progression of the detected first parameter, wherein the second parameter is determined from a temporal progression of electrical current consumption; and
a device for determining the actuating force applied to the vehicle brake from the first and second parameters.

22. The apparatus according to claim 21 , wherein the first parameter is detected at the vehicle brake.

Assignees

• Knechtges Josef
• Lucas Automotive Gmbh

Inventors

• Knechtges Josef

Classifications

• B60T13/58

  Combined or convertible systems · CPC title

• B60T13/66 Primary

  Electrical control in fluid-pressure brake systems · CPC title

• B60T13/588 Primary

  both fluid and mechanical assistance or drive · CPC title

• B60T13/741

  acting on an ultimate actuator · CPC title

• B60T8/17

  Using electrical or electronic regulation means to control braking {(detecting or indicating faulty operation B60T8/885)} · CPC title