Aisin Seiki Kabushiki Kaisha

Yoichi Terasaki

Kaoru Tsubouchi

Akihiko Miwa

Nobuyuki Hirota

Minoru Watanabe

A vacuum type brake booster for a vehicle is capable of compensating for inadequacy of the force with which a driver steps on a brake pedal during emergency braking whereby a reaction force corresponding to the output of the booster is applied to the brake pedal. A good brake pedal operation feeling is thereby obtained in both the outward and return strokes of the brake pedal and during when the booster has been switched to normal braking and when it has been switched to emergency braking.

Vacuum type brake booster for vehicle

A vacuum servo unit includes a partition member having an outer periphery that engages the movable wall member in an air tight manner. A receiving chamber is defined between the partition member and the movable wall member, and the receiving chamber is adapted to be communicated with the atmosphere. A passage that introduces atmospheric air into the receiving chamber is engaged in an air tight manner with the partition member and extends through the constant pressure chamber. A change member in the form of a solenoid valve selectively communicates the receiving chamber with the constant pressure chamber or with the atmosphere. Accordingly, the servo efficiency of the vacuum servo unit is increased. In addition, the unit can be operated automatically by supplying electric power to thereby increase brake force so that the brake feeling is advanced.

Growing community of inventors

Kariya, Japan

Yoichi Terasaki