PERFECCIONAMIENTOS EN MECANISMOS DE BARRAS DE CONTROL DE REACTORES NUCLEARES.

摘要

A control rod drive of the type wherein the load is actuated by a non-rotatable screwshaft driven axially within a sealed tubular enclosure includes a spinning nut assembly consisting of roller nuts mounted on pivoted segment arms and movable into and out of mesh with the screwshaft by energization and deenergization of an induction-type motor. The segment arms form a portion of the rotor so that when the field of stator rotates the roller nuts planetate to drive the shaft. A combined support and convection-controlling housing structure for the mechanism is adapted to be attached to the cover of a reactor vessel and includes an upwardly extending torque-taking piston-carrying section connected to the screwshaft and a snubbing cylinder for controlling the rate of descent and absorbing shock in event of scan, and means for parking the screwshaft in a raised position.