ELECTRIC DIRECT-ACTING ACTUATOR AND ELECTRIC BRAKE DEVICE

摘要

An electric direct-acting actuator capable of securing a large boosting function without assembling a separate speed reduction mechanism therein and an electric brake device. A plurality of planetary rollers (7) are interposed between the outer diameter surface of the rotor shaft (5) of an electric motor and the inner diameter surface of an outer ring member (1) fixed to the outer diameter side of the rotor shaft (5). Peripheral grooves (10) in which spiral projected lines formed of line members (9) peripherally fixed to spiral grooves (8) formed in the inner diameter surface of the outer ring member (1) are fitted are formed in the outer diameter surfaces of the planetary rollers (7) at the same pitch as that of the spiral projected lines so that the planetary rollers (7) can be revolved around the rotor shaft (5) while rotating about its axis according to the rotation of the rotor shaft (5). By converting the rotating motion of the rotor shaft (5) into the linear motion of the planetary rollers (7), the large boosting function can be secured without assembling the separate speed reduction mechanism therein.