Patent ID: 6889786

Claim:
An automatic brake system of a motor vehicle that has a brake pedal and a steering wheel installed therein, the system comprising: a first section that detects a relative connection between the vehicle and a preceding object ahead of the vehicle, said relative connection being provided based on a relative vehicle interval distance and a relative vehicle speed between the vehicle and the preceding object; a second section that, when actuated, produces a braking force applied to the vehicle, the braking force produced by the second section being isolated from a braking force produced by the brake pedal; a third section that, based on the relative connection detected by the first section, carries out a judgment as to whether or not a possible collision of the vehicle with the preceding object is avoidable by operation of at least one of the steering wheel and the brake pedal; a fourth section that, based on the relative connection detected by the first section, carries out an estimation as to whether or not, after expiration of a predetermined time from the time of detection of the relative connection, a possible collision of the vehicle with the preceding object is avoidable by operation of at least one of the steering wheel and the brake pedal; a fifth section that actuates and controls the second section in accordance with both a result of the judgment made by the third section and a result of the judgment made by the fourth section, thereby to control the braking force applied to the vehicle, wherein the fifth section is configured to carry out: causing the second section to produce a first grade braking force when the fourth section estimates that after expiration of the predetermined time the possible collision would be unavoidable by operation of either of the steering wheel and the brake pedal; and causing the second section to produce a second grade braking force when the third section judges that the possible collision would be unavoidable by operation of either of the steering wheel and the brake pedal, the second grade braking force being greater than the first grade braking force.