Patent ID: 6971484

Claim:
An electric disc brake comprising a piston for pressing a pad to a rotor via a ball ramp mechanism by driving an electric motor, wherein the ball ramp mechanism includes: a spherical member; two squeezing members, rotatable relatively, each having a circular-arc-shaped groove with a gradually changed depth, squeezing the spherical member in the circular-arc-shaped grooves, an excess rotation preventing mechanism for restricting excess rotation between the squeezing members to a predetermined range of rotation angle, wherein the excess rotation preventing mechanism comprises a first projected portion formed at one of the squeezing members and a second projected portion at other member thereof, and the first projected portion and the second projected portion are able to butt each other, and wherein the first projected portion is formed at a central opening of the one member, and the second projected portion is inserted into a central opening of the other member.