Patent ID: 9349532
Filing Date: 2016-05-24
CPC Classification: E02F,H01F,H02J

Claim Text:
1. A turning joint for an electric excavator, comprising: a DC/AC converter positioned at an upper swing structure of the excavator and configured to convert DC electric energy of an electric energy storage device into AC electric energy; an upper coil wound around the upper swing structure and configured to transfer an AC component converted by the DC/AC converter to a lower traveling structure by electromagnetic induction; a lower coil wound around the lower traveling structure and configured to receive an electromotive force of the AC component transferred from the upper coil; and an inverter configured to supply the electromotive force of the AC component transferred from the lower coil to an electric motor for traveling the lower traveling structure, as power required for operation of the electric motor; and a power interruption means for supplying the power only when the electric motor for traveling of the lower traveling structure requires the power by interrupting the power from the DC/AC converter so as to reduce an energy loss.