Patent ID: 8461785

Claim:
A variable speed electric motor speed controller comprising: a. A bridge rectifier comprising a plurality of bridge diodes connected to a filter capacitor C 1 for supplying power from a power source to an electric motor wherein the bridge rectifier maintains a constant polarity of power to the electric motor regardless of input polarity of power to the bridge rectifier; b. A first transistor Q 1 that receives power from the bridge rectifier and is connected to a second transistor Q 3 which is connected to a power transistor Q 5 in emitter follower configuration; c. A load resisting sensor R 9 connected to the motor and a Zenor Diode (D 5 ) whereby in an idle motor condition the first transistor Q 1 is forward biased by the power source and the second transistor Q 3 conducts and amplifies current that is then fed through the load resisting sensor R 9 to the motor and then back to the Zenor Diode D 5 and to the emitter of the first transistor Q 1 resulting in an output voltage of the motor equal to the voltage of the Zenor Diode D 5 and results in the motor turning at minimum speed; and d. A first variable resistor VR 1 wherein the first variable resistor VR 1 is connected to the load resisting sensor R 9 and monitors load increase to a third transistor Q 4 which causes the transistor Q 3 to conduct more power and thereby cause the motor speed to increase or decrease to match the applied load.