Laminated stator core for dynamoelectric machines

Claim 1

A stator core for a dynamoelectric machine, having slots which open radially inwardly to a circular bore and in which windings can be received to produce a pair of starting poles and a pair of running poles, the poles of each pair being disposed at opposite sides of one of a pair of mutually perpendicular diametral planes that lie on the axis of the bore, said core comprising flatwise superimposed laminations, and the laminations being characterized by: A. each lamination having 1. a substantially circular inner edge, 2. circumferentially spaced slots of two different radial depths opening to the inner edge, the slots of each depth being arranged in two like groups of circumferentially adjacent slots, a. the two groups of slots of smaller depth being at opposite sides of one of a pair of mutually perpendicular straight lines through the center of the inner edge, b. the two groups of slots of larger depth being at opposite sides of the other of said lines, and c. the two groups of slots of each depth being arranged symmetrically to both of said lines, and 3. the outer edge of each lamination having straight portions which are parallel to said lines and which peripherally alternate with arcuate portions curved on a uniform radius about said center, a straight portion parallel to said one line being closer to said center than any straight portion parallel to said other line and also being closer to said center than its diametrically opposite outer edge portion so that the lamination is asymmetrical about at least said one line; and B. said laminations being flatwise stacked in the core with their circular inner edges concentric and with substantially half of the laminations oriented at 180* to the other half, the orientations of the laminations along the stack varying in a regular sequence.