Other

Aisin Seiki Kabushiki Kaisha

Aisin Seiki K.k.

Koichi Kondo

Hiroshi Isono

Toshihisa Kato

Nobuyasu Nakanishi

Hiroaki Takeuchi

Yasuji Mizutani

Motoshi Suzuki

Hirofumi Nitta

Hiroshi Toda

Yasushi Kobayashi

Yutaka Onuma

Masaki Banno

Yasuhiro Abe

Hiroyuki Matsubayashi

Shinji Tsugawa

Hideyasu Miyata

Vehicle braking system including a vacuum booster for transmitting a boosted brake operating force to a master cylinder such that the boosting ratio is reduced at a fixed transition point before the boosting limit point is reached, a brake having a wheel brake cylinder connected through a fluid passage to a master cylinder serving as a first hydraulic pressure source, for braking a wheel, and a pressure increasing device having a second hydraulic pressure source connected to the fluid passage, and wherein the pressure increasing device initiating a pressure increasing operation, when the brake operating force has increased to the transition point, to increase the wheel cylinder pressure to be higher than the master cylinder pressure, by using the second hydraulic pressure source.

Braking system having vacuum booster whose boosting ratio is lowered at fixed transition point at which wheel cylinder pressure increase is initiated

The present invention is directed to an unpaved road detection system wherein a slip rate is calculated on the basis of wheel speeds detected by wheel speed sensors and a vehicle speed detected by a vehicle speed detection device. A linear acceleration sensor is provided for detecting an acceleration of the vehicle in a longitudinal direction thereof to produce a signal linearly proportional to the detected acceleration. A variation of the signal produced by the linear acceleration sensor corresponding to the variation of the slip rate is calculated. The variation of the signal is compared with a reference value. If the variation exceeds the reference value, it is determined that the vehicle is traveling on an unpaved road. The variation may be provided by calculating a difference between a first signal detected by the linear acceleration sensor when the slip rate exceeded a first reference rate, and a second signal detected by the linear acceleration sensor when the slip rate exceeded a second reference rate.

Unpaved road detection system

An anti-lock brake system is arranged such that the recirculation line from the overflow reservoir feeds into one of the brake lines downstream of the lines dividing point. A constriction, which may take the form of a simple nozzle is positioned between the recirculation line junction and the brake line dividing point for reducing the coupling of pressure fluctuations between the brake lines when the anti-lock system is actuated. With this arrangement, even upon the occurrence of sharp pressure fluctuations in one of the brake lines due to actuation of the anti-lock function, the pressure of the other brake line is not affected thereby allowing proper controlled braking in each wheel.

Wheel braking control apparatus for reducing pressure fluctuations

Growing community of inventors

Kasugai, Japan

Koichi Kondo