Patent ID: 7471019
Filing Date: 2008-12-30
Classification: H02K

Abstract:
1. A linear motor adapted to generate axial thrust on a shaft, the linear motor comprising: a pressure tube defining an annular volume with a pressure tube aperture to provide fluid to the annular volume; a plurality of stator windings; a shaft with a lumen extending therethrough from a radial aperture located in a portion of the shaft within the annular volume to an external aperture external to the annular volume, the shaft having magnetic generators to provide axial thrust in response to excitation of the stator windings, wherein the external aperture and the pressure tube aperture in the pressure tube are in fluid communication through the lumen in the shaft and the radial aperture, and wherein the stator windings comprise one or more axially distributed spacings through which fluid communication is provided between the radial aperture and the pressure tube aperture in the pressure tube.