Abstract: A locking mechanism capable of locking and unlocking the rotation of the rotor shaft of an electric motor is constituted by a plurality of recesses formed in one side surface of one gear of a plurality of gears of a reduction gear mechanism. A locking pin is movable toward and away from the recesses, and is configured such that when the locking pin moves toward the recesses, the locking pin engages in one of the recesses and locks the one gear. A linear solenoid is configured to move the locking pin toward and away from the recesses, and a protrusion extends from one end surface of each recess.

Abstract: A locking mechanism capable of locking and unlocking the rotation of the rotor shaft of an electric motor is constituted by: a plurality of recesses formed in one side surface of one gear of a plurality of gears of a reduction gear mechanism; a locking pin movable toward and away from the recesses, and configured such that when the locking pin moves toward the recesses, the locking pin engages in one of the recesses, and locks the one gear; and a linear solenoid configured to move the locking pin toward and away from the recesses. A protrusion extends from one end surface of each recess.

Abstract: An electric linear motion actuator includes a locking mechanism for locking and unlocking the rotor shaft of an electric motor. The locking mechanism includes circumferentially arranged locking holes provided in a gear of a reduction gear mechanism, a locking pin moved toward and away from the locking holes, and engaged in one locking hole to lock the gear when the locking pin is moved toward the gear, and a linear solenoid for moving the locking pin toward and away from the gear. The plunger of the linear solenoid and the locking pin are formed as separate parts, and disposed coaxial with each other with their end faces axially facing each other. This prevents the moment load applied from the gear to the locking pin from acting on the plunger, thereby preventing damage to a bobbin slidably supporting the radially inner surface of the plunger.

Abstract: An electric linear motion actuator includes: a rotary shaft to be driven by an electric motor; a plurality of planetary rollers kept in rolling contact with a cylindrical surface formed on an outer periphery of the rotary shaft; a carrier which retains the planetary rollers such that the planetary rollers are rotatable about axes thereof while revolving around the rotary shaft, and of which axial movement is restricted; and an outer ring member surrounding the planetary rollers and supported so as to be slidable in an axial direction. Helical ribs are formed on an inner periphery of the outer ring member; and circumferential grooves are formed on an outer periphery of each of the planetary rollers so as to be engaged with the helical ribs. A rotation of the rotary shaft is thus converted to a linear motion of the outer ring member.

Abstract: An electric linear motion actuator includes a locking mechanism for locking and unlocking the rotor shaft of an electric motor. The locking mechanism includes circumferentially arranged locking holes provided in a gear of a reduction gear mechanism, a locking pin moved toward and away from the locking holes, and engaged in one locking hole to lock the gear when the locking pin is moved toward the gear, and a linear solenoid for moving the locking pin toward and away from the gear. The plunger of the linear solenoid and the locking pin are formed as separate parts, and disposed coaxial with each other with their end faces axially facing each other. This prevents the moment load applied from the gear to the locking pin from acting on the plunger, thereby preventing damage to a bobbin slidably supporting the radially inner surface of the plunger.

Abstract: An electric linear motion actuator is provided which can set the clearance during normal braking operation of an electric brake system. The linear motion actuator includes a load sensor for detecting the magnitude of the load with which a friction pad is pressed against the brake disk, a temperature sensor for compensating for the influence of temperature on the load sensor, and an electronic control unit. The electronic control unit is adapted to calculate a target rotational angle from the position of the electric motor corresponding to the magnitude of the load detected by the load sensor to the position of the electric motor where the clearance is at a predetermined value, and control the electric motor to rotate the electric motor by the target rotational angle.

Abstract: A ball ramp mechanism is configured such that a driving-side rotor and a driven-side rotor are located on the same axis in opposing relationship with each other; three opposed pairs of arc-shaped ramp grooves are provided on the respective opposing faces of the two rotors at uniform intervals in the circumferential direction, with the depth thereof being changed gradually in the circumferential direction and the direction of the change being made opposite therebetween; a ball is incorporated between each set of the opposing paired ramp grooves; the balls are retained by the cage; and flexibility is imparted to pillar sections defined between pockets of the cage so as to make the pillar sections elastically deformable; dimensional variations due to manufacturing tolerances of the ramp grooves are absorbed via elastic deformation of the pillar sections so that each of the plurality of balls is enabled to contact the ramp grooves uniformly.

Abstract: An electric linear motion actuator capable of accurately controlling the axial position of an outer ring member is provided. A plurality of planetary rollers are kept in rolling contact with the cylindrical surface formed on the outer periphery of a rotary shaft. Helical ribs formed on the inner periphery of the outer ring member are engaged in circumferential grooves formed on the outer periphery of each of the planetary rollers. A carrier retains the plurality of planetary rollers. A revolution sensor detects the rotation angle of the carrier.

Abstract: An electric linear motion actuator is provided which can set the clearance during normal braking operation of an electric brake system. The linear motion actuator includes a load sensor for detecting the magnitude of the load with which a friction pad is pressed against the brake disk, a temperature sensor for compensating for the influence of temperature on the load sensor, and an electronic control unit. The electronic control unit is adapted to calculate a target rotational angle from the position of the electric motor corresponding to the magnitude of the load detected by the load sensor to the position of the electric motor where the clearance is at a predetermined value, and control the electric motor to rotate the electric motor by the target rotational angle.