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AssigneeWestinghouse Electric Corp.
InventorsHerbert E. Ferree, Thomas R. Wagner, Michael D. Hecht, Thomas J. Donnelly
Estimating the term…
An improved electric actuator is provided, having in association therewith a resolver. The actuator includes a stationary and a rotatable housing, and an electric motor within it. The electric motor drives the rotary housing through a speed reducing harmonic drive mechanism. The actuator has an opening in the rotary housing, and a cavity inwardly of the opening having a mating anchoring element connected with the stationary housing. A modular resolver is provided, of a shape and size to have a major portion of it occupy the cavity provided in the actuator, and having a mating part for engaging the mating part of the stationary housing, upon assemblage of the resolver to the actuator. A rotatable part of the resolver is secured to the rotary housing. A heat dissipation system is provided, including a fan mounted on a rotary member of the actuator and a closed circuit for the passage of air between the fan and a heat conductive plate forming a part of the stationary housing. Stability for the rotary housing is provided by widely spaced ball bearings supporting a rotary shaft extending from the rotary housing, the ball bearings being located at the maximum axial spacing within the stationary housing. In addition, an electromagnetic brake of lightweight construction is provided to prevent rotation of the rotary housing, and the resolver includes a coupling of the bellows type for elastic isolation from distortion of the parts, due to stresses between the fixed and rotary parts of the resolver.
In combination,
An electric robotic actuator comprising a stationary first housing, a second housing rotatably supported about said first housing in coaxial relationship therewith, rotating means for rotating said second housing relative to said first housing, said rotating means comprising a stator on said first housing and a rotor on a rotating member within said housings, speed reducing harmonic drive means for drivably connecting said rotor to said second housing, and heat transferring means for transferring heat from within said actuator to the exterior thereof, said heat transferring means comprising a heat conductive back plate of said first actuator housing and gas circulating means for circulating gas within said housings from a source of heat energy to said heat conducting back plate, said gas circulating means comprising a fan blade affixed to said rotating member within said housings, and passage means providing an air-circulation path from said fan blade to said heat conducting back plate and return from said heat conducting back plate to said fan blade.
Dependencies are inferred from the claim text.