Wireless power-supply system

• US 9,461,506 B2
• Filed: 02/03/2012
• Issued: 10/04/2016
• Est. Priority Date: 02/04/2011
• Status: Expired due to Fees

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Hatanaka, Takezo
• Primary Examiner(s): Wells, Kenneth B
• Assistant Examiner(s): Pacheco, Rafael
• Application Number:
  US13/983,085
• Publication Number:
  US 20140035385A1
• Time in Patent Office: 1,705 Days
• Field of Search: 307/104
• US Class Current: 1/1
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

The purpose of the present invention is to provide a wireless power-supply system using magnetic resonance, which is different from the conventional point of view. In a wireless power-supply system (101), the positional relationship (distance C) between a power-supply resonator (102) and a power-receiving resonator (103) denotes the power-supply range (F). In the power-supply range (F), the electric power transmitted as magnetic energy by resonating the power supply resonator (102) and the power receiving resonator (103) is more than the predetermined effective power. Therefore, the predetermined effective power can be transmitted only in the power-supply range (F) that maintains the positional relationship. On the other hand, when the power-receiving resonator (103) deviates from the power-supply range (F), the electric power cannot be transmitted.

Claims

1. A wireless power-supply system comprising:

a power transmission device including a power supply unit configured to supply power, and a power-supplying resonator configured to transmit the power supplied from the power supply unit in the form of electromagnetic energy; and

a movable power-receiving device including a power-receiving resonator and a power-receiving unit, the power receiving resonator having a same resonance frequency as that of the power-supplying resonator and being configured to receive the electromagnetic energy transmitted from the power-supplying resonator in the form of power, the power-receiving unit being configured to operate when the power received by the power-receiving resonator is predetermined effective power or more, wherein;

an area of a predetermined distance from the power transmission device is set as a power supply range, the predetermined distance being defined so as to correspond to a positional relation between the power-supplying resonator and the power-receiving resonator in which power transmitted in the form of electromagnetic energy by having the power-supplying resonator and the power-receiving resonator resonate with each other yields the predetermined effective power or more; and

the power-receiving unit is configured to operate only when the power-receiving device is within the power supply range.

2. The wireless power-supply system according to claim 1,

wherein

the positional relation between the power-supplying resonator and the power-receiving resonator is such that, at the resonance frequency band, a rate of the power output to the power-receiving unit relative to the power supplied to the power-supplying resonator is a rate that yields the effective power or more.

3. The wireless power-supply system according to claim 2, wherein:

the power-supplying resonator includes a power-supplying coil connected to the power supply unit and a power-supply end resonance coil; and

the power-receiving resonator includes a power-receiving coil connected to the power-receiving unit and a power-reception end resonance coil.

4. The wireless power-supply system according to claim 3, wherein:

a first distance between the power-supplying coil and the power-supply end resonance coil and/or a second distance between the power-reception end resonance coil and the power-receiving coil is freely settable.

5. A wireless power-supply method for a wireless power-supply system,

the system comprising:

a power transmission device including a power supply unit configured to supply power, and a power-supplying resonator configured to transmit the power supplied from the power supply unit in the form of electromagnetic energy; and

a movable power-receiving device including a power-receiving resonator and a power-receiving unit, the power-receiving resonator having a same resonance frequency as that of the power-supplying resonator and being configured to receive the electromagnetic energy transmitted from the power-supplying resonator in the form of power, the power-receiving unit being configured to operate when the power received by the power-receiving resonator is predetermined effective power or more,

the method comprising;

setting an area of a predetermined distance from the power transmission device as a power supply range, the predetermined distance being defined so as to correspond to a positional relation between the power-supplying resonator and the power-receiving resonator in which power transmitted in the form of electromagnetic energy by having the power-supplying resonator and the power-receiving resonator resonate with each other yields the predetermined effective power or more, and causing the power-receiving unit to operate only when the power-receiving device is within the power supply range.

6. A wireless power-supply system comprising:

a power transmission device including a power supply unit configured to supply power, and a power-supplying resonator configured to transmit the power supplied from the power supply unit in the form of electromagnetic energy; and

a plurality of movable power-receiving devices each including a power-receiving resonator and a power-receiving unit, the power receiving resonator having a same resonance frequency as that of the power-supplying resonator and being configured to receive the electromagnetic energy transmitted from the power-supplying resonator in the form of power, the power-receiving unit being configured to operate when the power received by the power-receiving resonator is predetermined effective power or more, wherein;

values of the predetermined effective power of the power-receiving devices are different from each other; and

for each power-receiving device, an area of a predetermined distance from the power transmission device is set as a power supply range, the predetermined distance being defined so as to correspond to a positional relation between the power-supplying resonator and the power-receiving resonator of the power-receiving device in which power transmitted in the form of electromagnetic energy by having the power-supplying resonator and the power-receiving resonator resonate with each other yields the predetermined effective power or more, and each power-receiving unit is configured to operate only when the corresponding power-receiving device is within its power supply range.