Automatic brake device for vehicle

PURPOSE: To prevent vibrational deceleration in the vicinity of an objective deceleration and also increase the accuracy of feedback control with quick deceleration assured at the time of automatic braking. CONSTITUTION: A control part 50 is provided which automatically increases the brake pressure of every wheel at a specific duty ratio for evading touching a forward obstacle and so on, and also feedback-controls the brake pressure so that the actual deceleration of own vehicle becomes the objective deceleration. The control part 50 has a dead zone setting means 53, regulating the increase and decrease of brake pressure always when a difference between the actual deceleration of own vehicle and the objective deceleration is in a dead zone having a given width during feedback control; and a correcting means 56, lessening the duty ratio of both pressure increase and decrease sides, and making correction so as to narrow the width of the dead zone when the actual deceleration of the own vehicle enters the dead zone. COPYRIGHT: (C)1993,JPO&Japio