Patent ID: 8106609

Claim:
A drive and evaluation unit for displacing an object comprising: a commutator motor with a stator having two diametrically opposed permanent magnets, the magnets each embodied by a cross-section having a circumferential contour segment with a radially inner circumferential contour segment; an armature having ten slots spaced apart circumferentially, the slots receiving armature windings embodied as lap windings, the armature windings each have a coil width that extends over three slots of the armature, wherein the radially inner circumferential contour segment of the magnets encompass the armature each via a respective inner circumferential angle thereof, and the circumferential angle of the radially inner circumferential contour segment of at least one of the permanent magnets is between 101° and 111°; a device for determining a rotary position of the armature by evaluating a waviness of the armature current or ripple count, wherein a lateral circumferential contour segment is provided on each of two sides of the permanent magnet, which sides are spaced apart in a circumferential direction and which connect the radially inner and radially outer circumferential contour segments to one another, and the lateral circumferential contour segments protrude in the circumferential direction past the radially inner circumferential contour segment in such a way that the permanent magnet encompasses the armature over a maximum circumferential angle between 106° and 117°.