Electric motor-driven brake apparatus

An electric motor-driven brake apparatus comprising:

• an electric motor driven according to a driving command;
• and
• a ball-screw mechanism converting rotation of the electric motor into a rectilinear motion to generate braking force;
• the ball-screw mechanism having a circular cylindrical nut member driven to rotate by a rotor core of the electric motor and a screw shaft engaged with an inner peripheral portion of the nut member through rolling elements and moved rectilinearly by rotation of the nut member;
• the nut member having a nut part engaged with the screw shaft and a rotor part axially extending from the nut part, the rotor core and the rotor part being connected to each other by press fitting.

An electric motor-driven brake apparatus comprising:

• a casing;
• an electric motor provided in the casing and driven according to a driving command from a controller;
• a rotation-rectilinear motion conversion mechanism supported by the casing and converting rotation of the electric motor into a rectilinear motion to propel a piston in a master cylinder;
• and
• a rotation detector installed in the casing and detecting a rotational position of the electric motor;
• the electric motor having a stator with windings and a rotor with permanent magnets;
• the rotation-rectilinear motion conversion mechanism having a cylindrical rotating member driven to rotate by the rotor of the electric motor, and a rectilinearly moving shaft member engaged with an inner peripheral portion of the rotating member through rolling elements and moved rectilinearly by rotation of the rotating member;
• the rotating member having an engaging part engaged with the rectilinearly moving shaft member and a rotor mounting part axially extending from the engaging part;
• the rotor being secured to the rotor mounting part by press fitting.