Patent ID: 7777385

Claim:
An actuator assembly, comprising: a motor assembly including a motor and a motor shaft, the motor configured to supply a first torque to the motor shaft; a harmonic drive gearbox coupled to receive the first torque from the motor shaft and operable, in response thereto, to supply a second torque; an actuator coupled to receive the second torque from the harmonic drive gearbox and configured, in response thereto, to move to a position; a latch rotor coupled to the motor shaft to rotate therewith, the latch rotor comprising a main body having a plurality of lobes that extend radially therefrom; one or more permanent magnets spaced apart from and at least partially surrounding the latch rotor, each of the one or more permanent magnets having one or more pole pairs and supplying a permanent magnetic field that opposes rotation of the latch rotor; and a latch electromagnet adapted to receive a flow of electrical current and configured, upon receipt thereof, to generate a magnetic field that simultaneously opposes all of the permanent magnetic fields supplied from the one or more permanent magnets or simultaneously aids all of the permanent magnetic fields supplied from the one or more permanent magnets, the electromagnet comprising: a latch stator non-rotationally mounted adjacent to, and at least partially surrounding, the latch rotor, the latch stator having the one or more permanent magnets mounted thereon, and a plurality of latch windings wound around at least a portion of the latch stator, the latch windings disposed adjacent the one or more permanent magnets and adapted to receive the flow of electrical current, the latch windings wound on the latch stator such that, upon receipt of the flow of electrical current, the latch windings generate the same number of magnetic pole pairs as there are permanent magnet pole pairs.