Patent ID: 8266976

Claim:
A direct drive electromechanical rotary-to-linear actuator, comprising: an elongated housing; a first electric motor, including a first stator fixed within the housing and a first rotor supported for rotation relative to the first stator; a second electric motor, including a second stator fixed within the housing and an elongated annular second rotor supported for rotation relative to the second stator; and, a planetary drive unit, comprising: an elongated central shaft coupled to the first rotor for conjoint rotation therewith and having one or more helical threads disposed on an external surface thereof; a planetary nut having a plurality of helical threads on an internal surface thereof and coupled to the annular second rotor within the annulus thereof for conjoint rotation therewith and for relative axial sliding movement therein; a plurality of planetary rollers disposed concentrically between the central shaft and the planetary nut, each roller having a helical thread on an external surface thereof that is complementary to and in rolling engagement with a thread of the shaft and a thread of the nut; and, a double-armature, double-disc solenoid clutch brake for independently locking respective ones of the first and second rotors against rotation relative to their respective stators.