| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotational-linear motion conversion mechanism (screw member) of an electric braking device of a vehicle that can maintain satisfactory lubrication state in a long term.SOLUTION: Rotational motion of an electric motor is converted to linear motion of a pressing member that presses a friction member through a screw member. Lubricant is provided in gaps (Cfk1, Cfk2, Csm, Cso) of the screw member. Control means rotates the electric motor in a normal rotation direction when pressing force is increased, and rotates the electric motor in a reverse rotation direction when the pressing force is decreased. When the pressing force is decreased, the electric motor is rotated in the reverse rotation direction while the lubricant existing in the gaps (Cfk1, Cfk2, Csm, Cso) moves from a position except first contact parts (Fmn1, Fon1) of the screw member that are in contact with each other when the pressing force is increased to the first contact parts (Fmn1, Fon1). |
