| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotary motion/linear motion converting mechanism (screw member) of an electric braking device of a vehicle, capable of keeping a high lubricating state for a long period.SOLUTION: A rotary motion of an electric motor is converted into a linear motion of a pressing member for pressing a frictional member, by a screw member. A lubricant is accumulated in a clearance gap of the screw member. Control means rotates the electric motor in a direction of normal rotation, when pressing force is increased, and rotates the electric motor in a reverse direction when the pressing force is decreased. When the pressing force is decreased, a rigidity value Gcp as an amount of change of the pressing force Fba to an amount of change of a rotary angle Mka of the electric motor is calculated, and the electric motor is rotated in the reverse direction until a time point t5 when a state that the rigidity value Gcp is less than a prescribed value gcpx, is continued over a time when a rotation angle Mka is changed by a prescribed rotation angle mky in the reverse direction. |
