RECIRCULATING BALL SCREW ROTARY ACTUATOR

• Main Author: MELLOR, MITCHELL
• Format: Patent
• Language: English; French
• Published: 01.10.2021
• Subjects: AEROPLANES; AIRCRAFT; AVIATION; BLASTING; COSMONAUTICS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR; ENGINEERING ELEMENTS AND UNITS; FLUID-PRESSURE ACTUATORS; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; HELICOPTERS; HYDRAULICS OR PNEUMATICS IN GENERAL; LIGHTING; MECHANICAL ENGINEERING; PERFORMING OPERATIONS; SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS

A rotary actuator for a hinged panel assembly, e.g., of a fixed-wing aircraft, includes ball bearings, an outer cylinder, a piston, and an inner shaft. The outer cylinder admits fluid pressure from a fluid pressure supply. The piston is circumscribed by the outer cylinder. The piston, outer cylinder, and ball bearings collectively forming an outer ball screw. The piston translates along a longitudinal center axis in response to the fluid pressure. The inner shaft is circumscribed by the piston, with the inner shaft, piston, and ball bearings collectively forming an inner ball screw that is concentric with the outer ball screw. The ball screws form an interlaced ball circuit with one or more shared ball paths. Piston translation rotates the piston and inner shaft, and to thereby recirculates the ball bearings between the outer ball screw and the inner ball screw through the interlaced ball circuit.