Patent ID: 7804213
Filing Date: 2010-09-28
Classification: F04D,H02K,Y10T

Abstract:
1. A miniature electrical motor and fluid pump assembly comprising: an impeller rotating about an axial shaft and including an impeller vane and a recess in a back side of the impeller, wherein the vane curves radially outward from a center air inlet coaxial to the axial shaft to an air discharge region radially outward of the impeller; a permanent magnet rotor arranged rotatably and concentrically with a stator, wherein the stator is coplanar with the rotor and magnetic fields of said stator being generated by energizing coils on the stator by an electronic commutator unit connected to the coils of the stator, the permanent magnet rotor is fixed to the back side of the impeller and an annular radial air gap separates the permanent magnet rotor and the energizing coils on the stator; a one-piece stator housing molding including a thermoplastic material of the housing integrally molded with the stator, wherein at least a portion of the stator housing molding extends into the recess in the backside of the impeller and the portion of the stator housing molding is coplanar with the impeller vanes and wherein the stator housing is adjacent an outer radial edge of the back side of the impeller; the coils are wound onto the stator and the coils are below the impeller vanes along an axial direction parallel to the axial shaft, and a bearing assembly seated in the stator housing molding, wherein the axial shaft is mounted in the bearing assembly and the bearing assembly includes a first bearing separated by a biasing device from a second bearing which are coaxial to and rotatably support the axial shaft, the first bearing is entirely above a first plane and the vane of the of the impeller is entirely below the first plane, and a second plane extends through the second bearing and the coils of the stator.