A multi cyclone collector with an improved structure is disclosed for providing the highest number of second cyclone collector by disposing a plurality of second cyclone collector in a non circular shape arrangement along a first cyclone collector, thereby increasing collecting efficiency. In one aspect, a power supply control circuit includes a controller to be coupled to a switch to regulate an output of a power supply in response to a feedback signal and a parameter change signal. The motor 10 generates electromagnetic resistance to oppose against rotations which input into the rotary shaft 11.