Abstract: An engaging projection formed on a back surface of a pressure plate is inserted into an engaging hole formed in an outside shim plate. A flat surface parts of the engaging projection constituting a side surface thereof are opposed to a linear parts of the engaging hole constituting an inner peripheral edge thereof. When the outside shim plate exists at a neutral position with respect to the pressure plate, the flat surface parts and linear parts are slightly inclined with respect to each other. A rotation of the outside shim plate about an axis of a piston based on a rotation force applied from a leading end face of the piston to the outside shim plate is regulated by line contact between the flat surface parts and linear parts.

Abstract: An engaging projection formed on a back surface of a pressure plate is inserted into an engaging hole formed in an outside shim plate. A flat surface parts of the engaging projection constituting a side surface thereof are opposed to a linear parts of the engaging hole constituting an inner peripheral edge thereof. When the outside shim plate exists at a neutral position with respect to the pressure plate, the flat surface parts and linear parts are slightly inclined with respect to each other. A rotation of the outside shim plate about an axis of a piston based on a rotation force applied from a leading end face of the piston to the outside shim plate is regulated by line contact between the flat surface parts and linear parts.

Abstract: An electric brake with a parking mechanism includes a parking lock device. A rotating side engaging surface of the parking lock device is formed with rotating side engaging projections at a plurality of places in a circumference direction of the rotating side engaging surface. One side surfaces in the circumference direction of the rotating side engaging projections are inclined edges which are inclined relative to a direction a restraining side engaging member of the parking lock device is displaced. The inclined edges are inclined in such a direction that a range in which the inclined edges and distal ends of the restraining side engaging member engage with each other is increased as the inclined edges go forward in a direction the restraining side engaging member moves based on an elastic force of an elastic member of the parking lock device.