Two speed single phase motor

Claim 1

A multiple speed dynamoelectric machine having at least a high speed and a low speed mode of operation comprising: a rotor assembly; a stator core constructed from a stack of laminations of suitable magnetic material, each of said laminations having a central opening therethrough with a plurality of notches extending generally radially outwardly from said central opening, the latter constituting a bore extending longitudinally through said core for reception of said rotor assembly and said notches constituting a plurality of slots extending longitudinally through said core for forming a plurality of winding receiving slots; a main winding including two physical poles, the latter each having one or more coils therein which are inserted in selected slots of said core with the main winding physical poles being on generally opposite sides of said bore, said main winding having a first predetermined number of effective turns therein in high speed mode and a second predetermined number of effective turns in low speed mode of operation; a supplemental winding including two physical poles, the latter each having at least one coil which is inserted in selected slots of said core, said supplemental winding having a third predetermined number of effective turns therein; a first auxiliary winding; a second auxiliary winding; and a plurality of leads electrically connected to said main, supplemental, and auxiliary windings for multiple speed operation of said dynamoelectric machine, said leads being so connected to said windings such that during high speed operation of the dynamoelectric machine said supplemental winding is energized and the high speed breakdown torque of the dynamoelectric machine is proportional to the inverse square of the sum of said first predetermined number of turns in said main wind plus the predetermined number of effective turns in said supplemental winding, and such that during low speed operation said supplemental winding is de-energized and the low speed breakdown torque of the dynamoelectric machine is proportional to the inverse square of the said second predetermined number of effective turns of said main winding whereby the torque of the dynamoelectric machine when operated at low speed may be preselected to be less than, equal to, or greater than the torque of the dynamoelectric machine when operated at high speed by selectively varying the number of turns in said main and supplemental winding.