Patent ID: 9059621
Filing Date: 2015-06-16
Classification: H02K

Abstract:
1. An electric rotating machine comprising a rotor with a rotor shaft located on a rotor axis and a stator rotatably receiving the rotor, wherein said stator includes a plurality of teeth, which extend towards a peripheral surface of said rotor and terminate at inner peripheral surfaces facing the peripheral surface of said rotor, and a plurality of slots, each between the adjacent two of the teeth, providing spaces in which a conductor wire is wound to form coils around said teeth for input of driving electric power, wherein said rotor has a plurality of permanent magnets embedded therein so as to let magnetic force act on that surface portions of the teeth which are opposed to the permanent magnets, wherein said rotor within said stator is driven to revolve by reluctance torque derived from magnetic flux passing through said teeth, rear surface sides of the teeth and said rotor when current passes through said coils and magnet torque in the form of attraction and repulsion derived from interference with said permanent magnets, wherein an outer diameter ratio of an outer diameter Dr of said rotor to an outer diameter Ds of said stator falls in a range effective for minimizing torque ripple, wherein the electric rotating machine is configured to satisfy conditions expressed as: where: Lt is the thickness of each of said plurality of teeth, Lb is the thickness of the rear surface side of each of said plurality of teeth, d is the diameter of said conductor wire of said coils, and Ls is the width of opening of each of said plurality of slots.