WIRELESS POWER TRANSMISSION DEVICE

摘要

A wireless power transmission device includes a main body, a first transmitter coil and a second transmitter coil. The second transmitter coil is partially stacked over the first transmitter coil. If the wireless power transmission device is operated in a detecting mode, a magnetic flux oriented in the direction toward the top surface of the main body is generated by the first transmitter coil. The magnetic flux is attenuated by the second transmitter coil. Consequently, the electromagnetic wave is inhibited. If the wireless power transmission device detects that an electronic device is located near the first transmitter coil, the first transmitter coil is controlled to be in a charging mode to transmit the magnetic flux to the electronic device, and the magnetic flux is no longer attenuated by the second transmitter coil.

主权项

1. A wireless power transmission device for wirelessly charging an electronic device, the wireless power transmission device comprising:
a main body; a driving circuit disposed within the main body, and providing a first voltage or a second voltage; a first transmitter coil disposed within the main body and located near a first lateral side of the main body; and a second transmitter coil disposed within the main body, located away from the first lateral side of the main body, and partially stacked over the first transmitter coil, wherein if the electronic device is not placed on the main body and the first transmitter coil is in a detecting mode, the driving circuit periodically provides the first voltage to the first transmitter coil at a first predetermined time interval, wherein a first magnetic flux is generated by the first transmitter coil according to the first voltage and the first magnetic flux is attenuated by the second transmitter coil, so that the attenuated first magnetic flux is periodically outputted from the wireless power transmission device at the first predetermined time interval, wherein if the electronic device is not placed on the main body and the second transmitter coil is in a detecting mode, the driving circuit periodically provides the first voltage to the second transmitter coil at the first predetermined time interval, wherein a second magnetic flux is generated by the second transmitter coil according to the first voltage and the second magnetic flux is attenuated by the first transmitter coil, so that the attenuated second magnetic flux is periodically outputted from the wireless power transmission device at the first predetermined time interval, wherein if the electronic device is placed on the main body and located near the first transmitter coil, the driving circuit provides the second voltage to the first transmitter coil, so that the first transmitter coil is in a charging mode and the first transmitter coil generates a third magnetic flux to a receiver coil of the electronic device, wherein if the electronic device is placed on the main body and located near the second transmitter coil, the driving circuit provides the second voltage to the second transmitter coil, so that the second transmitter coil is in the charging mode and the second transmitter coil generates a fourth magnetic flux to the receiver coil.