Patent ID: 7554226

Claim:
An axial air gap type electric motor comprising: a stator having tease portions on first and second side faces; first and second rotors, each rotor having a permanent magnet oppositely arranged with a predetermined air gap between the permanent magnet and the respective tease portion; a rotating shaft arranged on a rotating axis of the first and second rotors and fixing the first and second rotors thereto; first and second ball bearings each having an inner ring fixed to the rotating shaft by pivoting the rotating shaft; an outer ring of the first ball bearing fixed to the stator; a pre-pressurizing section for pre-pressurizing an outer ring of the second ball bearing in a first axial direction, the pre-pressurizing section comprising a ring-shaped leaf spring located between the outer ring of the second ball bearing and the stator, the leaf spring having a vertex contacting the outer ring of the second ball bearing and a vertex contacting the stator; a stopper located between the vertex contacting the outer ring of the second ball bearing and the stator; a magnetic pre-pressurizing section for pre-pressurizing the inner rings in a second axial direction by a difference of magnetic force of the axial direction in one of the air gaps and the other of the air gaps, wherein the first axial direction and the second axial direction are the same, and a plurality of stoppers located between the ring-shaped leaf spring and the stator, wherein the stoppers are arranged in diametrically opposed pairs with respect to the rotating axis.