Patent attributes
The present invention provides a power transmission transformer of which workability in implementing and reliability of connection are considered in a noncontact power transfer device using individual self-oscillation circuits. The power transmission transformer for a noncontact power transfer device including a transmitting coil L1 and a drive coil L2 for self-oscillation on a power transmission device side includes a bobbin in which the transmitting coil and the drive coil L2 are disposed, in which the transmitting coil and the drive coil L2 are configured by an air-core coil using self-bonding wire, and the bobbin 1 includes a winder spindle 1a, 1b on both surfaces opposed to each other across a collar 2 formed of a flat plate, and a mating portion 3 for mating with an external portion in an end portion of the winder spindle 1b, and the drive coil L2 is mounted on the winder spindle 1b and the transmitting coil L1 is mounted on the other, opposed winder spindle 1a across the collar.