Patent Number: 6,305,757

Title: Brake booster negative pressure controller

Abstract: In order to provide a brake booster negative pressure controller which reduces deterioration in the fuel consumption due to operation for closing a throttle to assure a brake booster negative pressure while assuring the braking capability required according to driving conditions and can safely assure a braking capability even when a failure occurs in a negative pressure sensing system, said brake booster negative pressure controller comprises a brake booster for assuring a master vac negative pressure by using a negative pressure of an engine, a throttle valve whose opening angle can be operated independently from the stroke of an accel pedal, and a brake operation sensing means, wherein the negative pressure controller has a speed sensing means and a means for closing the throttle valve by a predetermined amount when the vehicle speed sensed by the vehicle speed sensing means is equal to or higher than a predetermined value and application of the brake is sensed by the brake operating sensing means.

Inventors: Ohsaki; Satoru (Hitachinaka, JP), Takano; Yoshiya (Hitachinaka, JP), Yano; Hirofumi (Yokohama, JP)

Assignee: Hitachi, Ltd.

International Classification: B60T 13/46 (20060101); B60T 17/00 (20060101); B60T 17/02 (20060101); F02D 41/00 (20060101); B60T 008/44 ()

Expiration Date: 10/23/2018