Voltage-induction type electrostatic film motor driven by two- to four-phase ac voltage and electrostatic induction

This paper describes a voltage-induction type electrostatic film motor that operates by feeding electric power to the slider by electrostatic induction. In the electrostatic motor, applying voltages to both of its stator and slider contributes to its fine positioning resolution and better controllability. However, in some cases such as relatively small motors, the electric wires connected to the slider could cause mechanical disturbances to the motor motion. In the new electrostatic motor, electric wires are connected only to the stator, thus the slider motion is not disturbed. The power to the slider is transferred by electrostatic induction between induction electrodes fabricated in both of the stator and the slider. The proposed motor has a two- to four-phase driving-electrode configuration, which consists of a two-phase driving electrode in the slider and a four-phase driving electrode in the stator. The paper first analyzes the thrust force characteristics of the driving-electrode configuration, and then analyzes the characteristics of voltage-induction configuration, both based on capacitance-network analysis. Experimental results showed good agreements with the analyses, confirming the feasibility of the voltage-induction type electrostatic motor.