Aisin Seiki Kabushiki Kaisha

Advics Co., Ltd.

Nobuyuki Hirota

Kaoru Tsubouchi

Akihiko Miwa

Minoru Watanabe

Tomoyasu Sakai

Yoichi Terasaki

Yoji Inoue

Kenichi Kobayashi

Yu Furuta

Eri Tanimoto

A valve mechanism of this negative pressure type booster device has: a negative pressure valve seat provided on a valve body; an atmospheric valve seat provided on a plunger; and a valve part provided with a negative pressure valve section constituting a negative pressure valve together with the negative pressure valve seat and an atmospheric valve section constituting an atmospheric valve together with the atmospheric valve seat. The valve mechanism is provided with a tilting part which is provided on at least one of the valve body and the valve part and tilts the atmospheric valve section relative to a first plane formed when the negative pressure valve section and the negative pressure valve seat are brought into contact with each other to put the negative pressure valve in a closed state.

Negative pressure-type booster device

A vacuum booster which moderates a retraction speed of a valve seat member to restrain a contact noise between a key member retracting in a unitary manner with the valve seat member and a flange surface of a plunger. The vacuum booster includes a noise restriction device.

Vacuum booster

A negative pressure type booster device possesses a valve mechanism constructed to compensate for insufficient depressing force applied to a brake pedal upon emergency braking. Upon depression of the brake pedal, first negative pressure valves contact first negative pressure valve seats to block a variable pressure chamber from communication with a constant pressure chamber, and an atmosphere valve seat is separated from an atmosphere valve to communicate the variable pressure chamber with atmosphere. A partition member thus moves forwards depending on the pressure difference between the chambers to output a propelling force from an output rod. When the brake pedal is stepped on quickly, a valve member is urged backwards by a spring member causing second negative pressure valve seats to contact second negative pressure valves and move the valve member backwards. The atmosphere valve separates from the atmosphere valve seat, and the variable pressure chamber quickly communicates with atmosphere.

Negative pressure type booster device

A negative pressure type booster, comprising a valve seat member ( ), a spring ( ) energizing the valve seat member ( ), and a holding member ( ) having an engaging part ( ) disposed on a power piston ( ) movably only in radial direction and engaged with the valve seat member ( ) and a tapered part ( ) in contact with a plunger ( ), whereby, when the amount of movement of an input member ( ) relative to the power piston ( ) is larger than a specified value, the input member ( ) is brought into contact with the tapered part ( ) and moves the holding member ( ) in radial direction to disengage the holding member ( ) from the valve seat member ( ) in order to allow the valve seat member ( ) to be moved rearwards.

Negative pressure type booster

A negative pressure type servo unit which allows the size of the actuator to be reduced includes a housing, a movable wall positioned in the housing, a power piston, an input member, a plunger, a valve mechanism, an output rod, an actuator and a seal member. The seal is designed to include a first engaging portion and a second engaging portion producing a pressure difference on a front side and a rear side of the seal.

Negative pressure type servo unit

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.

Growing community of inventors

Aichi-ken, Japan

Nobuyuki Hirota