Patent ID: 7999649

Claim:
A power transmission transformer for a noncontact power transfer device including a transmitting coil and a drive coil for self-oscillation on a power transmission device side, the power transmission transformer comprising a bobbin in which the transmitting coil and the drive coil are provided in a prescribed location, wherein the transmitting coil and the drive coil are configured by an air-core coil using self-bonding wire, the bobbin has: a first bobbin including a winder spindle on both surfaces opposed to each other across a collar composed of a flat plate, and a mating portion in one end portion of the winder spindle; and a second bobbin including a plurality of external terminals and a mating hole in the central portion, the drive coil is mounted on the winder spindle of the first bobbin on the mating portion side, and the transmitting coil is mounted on the other, opposed winder spindle across the collar, and the first bobbin and the second bobbin are fitted together.