Brake control apparatus for vehicle

• US 20070138861A1
• Filed: 12/15/2006
• Published: 06/21/2007
• Est. Priority Date: 12/15/2005
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Yokoyama, Atsushi, Nishigaito, Takaomi, Kawahara, Yoshinari, Nogami, Tadahiko
• Granted Patent: US 7,565,954 B2
• Time in Patent Office: Days
• US Class Current: 303/20
• CPC Class Codes: B60T 13/741 acting on an ultimate actuator

Abstract

A brake control apparatus for a vehicle having brake devices for generating pad-pressing forces at respective wheels includes brake control units for individually controlling the pad-pressing forces at the respective wheels; a storing unit for storing drive data required for controlling the pad-pressing force at each wheel; a vehicle-driving-state detector for detecting a driving state of the vehicle; and a vehicle controller for controlling a vehicle driving state using the brake control unit for each wheel. Memory data representing the relationship between a motor position and the pad-pressing force is updated using the state of brake actuators obtained when the driving state of the vehicle is stabilized by operating the brake devices during braking.

Claims

1. A brake control apparatus for a vehicle having brake means for applying braking forces to wheels using respective brake friction members, the brake control apparatus comprising:

brake control means for individually controlling displacements of the brake friction members;

storing means for storing drive data required for controlling the displacements;

a vehicle-driving-state detector for detecting a physical value that indicates a driving state of the vehicle; and

a vehicle controller for controlling the driving state of the vehicle using the brake control means for each wheel on the basis of the detected physical value,

wherein the vehicle controller acquires control data as a result of controlling the driving state of the vehicle with the brake means, corrects the drive data stored in the storing means using the acquired control data, and updates the drive data stored in the storing means.

4. The brake control apparatus according to claim 1, wherein the vehicle controller acquires the control data on the basis of a pressing force applied to each wheel after vehicle-stabilizing control, the vehicle-stabilizing control being performed when a yaw angular velocity is equal to or more than a predetermined value during brake control performed in response to a brake command.

6. The brake control apparatus according to claim 1, wherein the drive data is corrected and updated at the time when legally required inspections of the vehicle is performed.

7. The brake control apparatus according to claim 1, wherein the vehicle controller receives a travel distance of the vehicle from a travel-distance detector and issues a warning that the drive data is to be corrected and updated when the total travel distance reaches a predetermined value.

8. The brake control apparatus according to claim 1, wherein the drive data includes characteristic data representing the relationship between a motor position and a pressing force applied to a brake pad.

9. The brake control apparatus according to claim 4, wherein the correction of the drive data is performed when a predetermined time is elapsed after the start of the vehicle-stabilizing control, when a steering angle during braking performed by the brake means is less than a predetermined value, and when a variation width of the yaw angular velocity during the vehicle-stabilizing control is less than a predetermined value.

10. The brake control apparatus according to claim 1, wherein the brake means includes a motor and a piston for each wheel, the motor generating a driving force to move the piston, the movement of the piston causing the corresponding brake friction member to come into contact with a rotating member that rotates together with the wheel, and

wherein the drive data is characteristic data representing the relationship between data of displacement of the piston and data of pressing force applied between the brake friction member and the rotating member.

2. A brake control apparatus for a vehicle having brake means for applying braking forces to wheels using respective brake friction members, the brake control apparatus comprising:

brake control means for individually controlling displacements of the brake friction members;

storing means for storing drive data required for controlling the displacements;

a vehicle-driving-state detector for detecting a physical value that indicates a driving state of the vehicle; and

a vehicle controller for controlling the driving state of the vehicle using the brake control means for each wheel on the basis of the detected physical value,

wherein the vehicle controller acquires control data as a result of causing the brake means to perform a predetermined operation while the vehicle is stationary, corrects the drive data stored in the storing means using the acquired control data, and updates the drive data stored in the storing means.

5. The brake control apparatus according to claim 2, wherein the vehicle controller receives a correction command signal for correcting the drive data, performs a pressing-force increasing/decreasing operation of increasing and decreasing a pressing force applied to each wheel after confirming that the vehicle is stationary, and then acquires the control data based on a motor current obtained as a result of the pressing-force increasing/decreasing operation.

3. A brake control apparatus for a vehicle having brake means for applying braking forces to wheels using respective brake friction members, the brake control apparatus comprising:

brake control means for individually controlling displacements of the brake friction members;

storing means for storing drive data required for controlling the displacements;

a vehicle-driving-state detector for detecting a physical value that indicates a driving state of the vehicle; and

a vehicle controller for controlling the driving state of the vehicle using the brake control means for each wheel on the basis of the detected physical value,

wherein the vehicle controller acquires control data as a result of controlling the driving state of the vehicle with the brake means and also acquires control data as a result of causing the brake means to perform a predetermined operation while the vehicle is stationary, and

wherein the vehicle controller corrects the drive data stored in the storing means using the acquired control data, and updates the drive data stored in the storing means.