Method and device for controlling a brake system for a vehicle

• US 20040207257A1
• Filed: 05/10/2004
• Published: 10/21/2004
• Est. Priority Date: 09/04/1997
• Status: Active Grant

• Current Assignee: Helmut Wiss, Ian Faye
• Original Assignee: Helmut Wiss, Ian Faye
• Inventors: Faye, Ian, Wiss, Helmut
• Granted Patent: US 6,962,396 B2
• Time in Patent Office: Days
• US Class Current: 303/125
• CPC Class Codes: B60T 2201/03 Brake assistants
• 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
• CPC Class Codes: B60T 8/3275 Systems with a braking assistant function, i.e. automatic full braking initiation in dependence of brake pedal velocity

Abstract

A method and a device for controlling a brake system of a vehicle, with an automatic braking action being triggered when a threshold value is exceeded. The threshold value is varied as a function of a quantity derived from the distance to an obstacle located in front of the vehicle.

Claims

1. A method for controlling a brake system of a vehicle, comprising the steps of:

modifying a braking force at wheel brakes of the vehicle when the brake system is controlled by a driver of the vehicle;

determining at least one performance quantity indicative of a hazardous situation as a function of a distance from the vehicle to an obstacle located in front of the vehicle;

triggering an automatic braking action using at least one signal when at least one predetermined threshold value is exceeded, the at least one signal representing an operation of a braking element of at least one of the wheel brakes, wherein the at least one predetermined threshold value is dependent on the at least one performance quantity; and

if a potential danger of a hazardous situation increases, increasing a sensitivity of the triggering of the automatic braking action.

2. The method according to claim 1, wherein the at least one performance quantity is indicative of a relative velocity of the vehicle with respect to the obstacle.

3. The method according to claim 2, wherein the relative velocity of the vehicle is determined as a function of a change in the distance from the vehicle to the obstacle and as a function of a road speed of the vehicle.

4. The method according to claim 1, wherein the at least one performance quantity is indicative of status information of a cruise control system, the status information indicating whether the cruise control system is operating in a servo control mode.

5. The method according to claim 1,

wherein the automatic braking action is triggered as a function of a closing status of a brake switch of the vehicle in the hazardous situation, and

wherein the closing status is detected as a function of the at least one performance quantity.

6. The method according to claim 1, further comprising the step of:

modifying the at least one predetermined threshold value only if a cruise control system of the vehicle is inactive.

7. The method according to claim 1, wherein the braking force is modified by increasing or decreasing the braking force.

8. A device for controlling a brake system of a vehicle having wheel brakes, the device comprising:

a control unit modifying a brake force at the wheel brakes when a driver of the vehicle controls a braking input, the control unit receiving a signal representing an operation of a control element for at least one of the wheel brakes activated by the driver, the control unit including an arrangement providing at least one predetermined threshold value for triggering an automatic braking action of the vehicle,

wherein the control unit initiates the automatic braking action when an operating quantity-exceeds the at least one predetermined threshold value, and

wherein the control unit modifies the at least one predetermined threshold value as a function of at least one performance quantity indicative of a hazardous situation, the at least one performance quantity being determined as a function of a distance from the vehicle to an obstacle located in front of the vehicle.

9. The device according to claim 8, wherein the control unit modifies a brake force by increasing or decreasing the brake force.

10. The device according to claim 8, further comprising:

a further control unit controlling an adaptive cruise control system and providing the at least one performance quantity to the control unit.