| 摘要 |
PURPOSE:To eliminate the influence of frequency by a method wherein a condenser is charged and discharged through variable resistance and a fixed condenser by the voltage between both poles of a current control element serially connected with an electromotor and said voltage is impressed on a control element gate. CONSTITUTION:An induction motor 6 and a current control element 7 are serially connected with an AC power 9 to charge and discharge a condenser 5 through the composite impedance of variable resistance 3 and a fixed condenser 2 by the voltage between both poles of the control element, said voltage is impressed on a gate 10 of the control element 7 to control the revolution speed of the motor 6. By further properly selecting the value of the variable resistance 3 and the condenser 2 and the like in this way a widely usable control device, of which control action does not depend on whether the power source frequency of 50Hz or 60Hz, can be obtained. |
