Capacitor-type motor speed controller

A motor speed controller for quietly controlling the speed of an AC motor driven by an AC source, comprising:

• a) a first impedance comprising a first capacitor in series with a first resistor electrically connected in series with said AC motor and said AC source to establish a first AC motor speed;
• b) a second impedance comprising a second capacitor in series with a second resistor adapted to be selectively electrically connectable in parallel with said first impedance to establish a second AC motor speed, less than said first AC motor speed;
• and
• c) switch means between said first and second impedances for selectively connecting said second impedance in parallel with said first impedance to vary the drive signal provided by said AC source to drive said AC motor.

A motor speed controller for controlling the speed of an AC motor driven by an AC source such that minimal audible noise is generated at switching motor speeds, comprising:

• a) a first impedance comprising a first capacitor in series with a first resistor electrically connected in series with said AC motor and said AC source to establish a first AC motor speed;
• b) second through N impedances, each comprising a capacitor in series with a resistor and arranged to be placed in parallel with said first impedance;
• and
• c) N-1 switching means each connected between two adjacent impedances in sequential order to decrease the AC signal applied to said AC motor and cause said motor to operate at a lesser speed.