Patent ID: 6321030
Filing Date: 2001-11-20
Classification: H02P

Abstract:
A controller for DC motors, comprising:A) a source of A.C. voltage passing through A.C. zero voltage two times per cycle;B) first full wave rectifying means having a first input connected to said AC voltage and two first outputs producing a first wave rectified voltage going to zero voltage in synchronization with said A.C. zero voltages;C) D.C. motor means having first and second inputs, said first input being connected to one of said two first outputs;D) second full wave rectifying means having a second input connected to said AC voltage and a second output providing a full wave rectified voltage going to zero voltage in synchronization with said A.C. zero voltages;E) means for generating an output signal synchronized to said A.C. zero voltages;F) means for generating a unipolar waveform output voltage with a zero start voltage that coincides with said output signal;G) switching means for turning on and off the connection of the second input of said D.C. motor means to the other output in response to said unipolar waveform output driving said switching means, said switching means being synchronized with said A.C. zero voltages; andH) means for varying times for turning on and off said switching means by changing the pulse width of said unipolar waveform output voltage driving said switch means.