Patent ID: 8664826

Claim:
An electric motor ( 1 ) comprising a stator ( 2 ) and a radially symmetric, permanent-magnet excited rotor ( 4 ) provided for rotation relative to the stator ( 2 ) about a common motor axis (X), the stator ( 2 ) having a radially symmetric iron core ( 6 ) with a plurality (N) of stator teeth ( 10 ) adjacent to each other in a circumferential direction and separated by stator slots ( 8 ) forming slot openings ( 8 a ), the rotor ( 4 ) having a plurality (P) of circumferentially distributed pole magnets ( 14 ), the pole magnets ( 14 ) being adjacent to one another via pole transitions ( 14 a ), an annular gap ( 18 ) being formed radially between the pole magnets ( 14 ) of the rotor and the stator teeth ( 10 ), each stator tooth ( 10 ) of the stator teeth having, on its surface ( 20 ) facing the gap ( 18 ), two side regions, each of the side regions circumferentially proximate to one of the slot openings ( 8 a ), each of the two side regions forming a relief-like topographic region ( 22 ) radially enlarging the gap ( 18 ), each topographic region having a plurality of concave recesses ( 24 ) merging into one another without interruption and forming an uninterrupted, wave-like, smooth and edge-free profile in the circumferential direction, each stator tooth having, on its surface ( 20 ) facing the gap ( 18 ), only concave recesses that are part of one of the pluralities of concave recesses, each concave recess of each plurality of concave recesses having a radially measured maximum depth, the maximum depths of each plurality of concave recesses decreasing with increasing angular distance (φ) from a central axis of the slot ( 26 ).