Linear actuator and rocking controller for railway vehicle

Abstract

To provide a compact linear actuator having small back drive force. The linear actuator includes: a hollow rotor that has a magnet fixed to a part of the outer peripheral surface thereof and having an open end and a closed end; a main body that has a hollow structure having an open end and a closed end and rotatably accommodates the rotor in the hollow structure, and is fixed with a stator winding facing the magnet; a linear motion converting section that is arranged in the hollow section of the rotor and is linearly moved in the axial direction by the rotation of the rotor; a linear motion rod that has one end fixed to the linear motion converting section, and the other end extended from the open end of the main body, and has, on the outer periphery thereof, a slide section made to slide in the axial direction with respect to a linear motion seal of the opening of the main body; and a resolver that is configured by a rotator fixed at the radial outer side of the outer peripheral surface of the rotor and on the open end side of the closed end section of the rotor, and a stator fixed to the main body at a part of the angular range on the radial outer side of the rotator, the linear actuator being configured such that the rotor is supported by the main body at the open side and the closed end of the magnet and the stator winding so as to be rotatable about the axis of the rotor, and such that the whole of the hollow rotor is accommodated in the sealed space.