Circuit and method of driving a DC motor
 A circuit and a method of driving a DC motor is provided in which a DC power to be supplied to the DC motor is oscillated in phase for producing a variable torque. As the torque is varied, its peak value increases while its average remains unchanged. Hence, the maximum torque needed for starting rotation will successfully be obtained. Once the rotation starts, a lower torque is accepted for continuous rotation of a load. The rotation can thus be conducted by a lower amplitude of the variable torque. Accordingly, when the rotating torque of the motor becomes low due to increase in unwanted load or declination in capability, the motor can remain operable without troublesome repair or replacement. 
Nippon Densan Corporation
H H
H02P H02P
inventional inventional
Yoichi
Mori