Patent attributes
Provided is an electric actuator (1), including: a motor part (A); and a motion conversion mechanism part (B). The motion conversion mechanism part (B) includes: a ball screw shaft (33); and a ball screw nut (32), which is rotatably fitted to an outer periphery of the ball screw shaft (33), and is provided so as to be capable of transmitting torque with a rotor (24) of the motor part (A) rotatably supported through intermediation of a rolling bearing (27, 30). The ball screw shaft (33) advances toward one side in the axial direction or retreats toward another side in the axial direction in accordance with a rotation direction of the ball screw nut (32). In the electric actuator (1), a needle roller bearing (47) serving as a thrust bearing is arranged adjacent to the ball screw nut (32) on the another side in the axial direction.