| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce a dimension in the axial direction while eliminating a sense of incongruity of brake pedal operation when executing regenerative cooperative control, in an electric booster. <P>SOLUTION: In ordinary braking, operation of an electric motor 14 is controlled in response to an operation quantity of a brake pedal 13, and a pressing member 17 is driven via a belt transmission mechanism 15 and a ball screw mechanism 16, and braking force is provided by generating hydraulic pressure in a master cylinder 2 by pressing a piston 7. Constant reaction is imparted to the brake pedal 13 by a reaction spring 34 of a stroke simulator 18, and the sense of incongruity of brake operation by a hydraulic pressure variation in the master cylinder 2 is eliminated by maintaining a clearance δ between the pressing member 17 and a movable member 33. When the electric motor 14 falls, the movable member 33 abuts on the pressing member 17 (δ=0), and the braking function is maintained by directly pressing the piston 7. The dimension in the axial direction is reduced by inserting a rear end part of the pressing member 17 into a guide member 32 and the reaction spring 34. <P>COPYRIGHT: (C)2012,JPO&INPIT |
