PURPOSE: To perform power transmission in non-contact state, by performing the power transmission with a capacitance between the first electrode forming member supported by a static system and the second electrode forming member supported by a rotary system and arranged oppositely to the first electrode forming member.

CONSTITUTION: The first electrode forming member 1 is supported by a static system, while the second electrode forming member 2 is supported by a rotary system. The second electrode forming member 2 is also allowed freedom of rotation right and left as shown in an arrow 4 with a central shaft 3 as the centre of rotation, keeping the condition to face the first electrode forming member 1. Having an AC power source the static system is constituted, while having a load the rotary system is constituted. A conjunction with a capacitor 7 formed by the first and second electrodes 1 and 2 between both systems enables the AC power to transfer from the static system to the rotary system in non-contact state.