Patent ID: 8096122
Filing Date: 2012-01-17
Classification: B60T

Abstract:
1. An electric booster, comprising: an axial member movable forward and backward in response to an operation of a brake pedal; a cylindrical member disposed around the axial member so as to be movable relative to the axial member; and an electric actuator operable to cause a forward/backward movement of the cylindrical member, wherein the axial member and the cylindrical member face a primary pressure chamber of a tandem master cylinder having a secondary piston which separates the primary pressure chamber and a secondary pressure chamber; a reactive force of a brake fluid pressure generated in the tandem master cylinder is transmitted to the axial member; and the electric booster comprises a transmission member operable to transmit a reactive force by a fluid pressure in the secondary pressure chamber of the tandem master cylinder to the axial member when a fluid pressure is not generated in the primary pressure chamber by a movement of the axial member.