Method of data transmission embedded in electric power transmission and a charging stand and battery device using transmitting coil current change to receive that data transmission

• US 8,188,854 B2
• Filed: 07/02/2009
• Issued: 05/29/2012
• Est. Priority Date: 07/03/2008
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Yamashita, Takahiro
• Primary Examiner(s): HOFSASS, JEFFERY A
• Application Number:
  US12/496,988
• Publication Number:
  US 20100001845A1
• Time in Patent Office: 1,062 Days
• Field of Search: 340/558, 3406361-6362, 320/108, 336/DIG.2
• US Class Current: 340/538
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/0045 concerning the insertion or the connection of the batteries

Abstract

The method of data transmission embedded in electric power transmission disposes a transmitting coil 11 and a receiving coil 31 in close proximity, transmits electric power in a non-contact fashion from the transmitting coil 11 to the receiving coil 31 by magnetic induction, and transmits data from the receiving coil 31 side to the transmitting coil 11 side. The method of data transmission changes the load on the receiving coil 31 and detects transmitting coil 11 current change corresponding to that load variation to send data from the receiving coil 31 side to the transmitting coil 11 side.

Claims

1. A method of data transmission embedded in electric power transmission that disposes a transmitting coil and receiving coil in close proximity to transmit power in a non-contact fashion from the transmitting coil to the receiving coil by magnetic induction, the method comprising:

a step to change the load on the receiving coil; and

a step to detect transmitting coil current change corresponding to the load variation to receive data transmitted from the receiving coil to the transmitting coil.

2. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein the load on the receiving coil is changed in specific patterns to transmit data to the transmitting coil side.

3. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein data are transmitted in an asynchronous fashion at the receiving coil side and the transmitting coil side.

4. The method of data transmission embedded in electric power transmission as cited in claim 3 wherein asynchronous data are transmitted at rate of 50 bits per second (bps) to 500 bps.

5. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein batteries are charged by output from the receiving coil, and data indicating the condition of the batteries being charged are sent from the receiving coil side to the transmitting coil side.

6. The method of data transmission embedded in electric power transmission as cited in claim 5 wherein transmitting coil power transmission is stopped when battery full-charge data are sent from the receiving coil side to the transmitting coil side.

7. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein data sent from the receiving coil side to the transmitting coil side are data indicating excessive supply of power or insufficient supply of power.

8. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein data sent from the receiving coil side to the transmitting coil side are data for the batteries charged by the receiving coil, and that data are battery voltage, current, temperature, or battery identification (ID) information.

9. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein the load on the receiving coil is changed by open-circuiting the load.

10. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein the load on the receiving coil is changed by reducing the load resistance.

11. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein the load on the receiving coil is changed in a transient fashion for pulse transmission of data.

12. The method of data transmission embedded in electric power transmission as cited in claim 1 wherein data sent from the receiving coil side to the transmitting coil side are charging error data.

13. A charging stand and battery device comprising:

a charging stand that has a transmitting coil and supplies alternating current (AC) power to that transmitting coil; and

a battery device that has a receiving coil disposed in close proximity to the charging stand transmitting coil;

the battery device further comprising;

a data transmission circuit that changes the load on the receiving coil according to data to be transmitted to the charging stand;

the charging stand further comprising;

a data receiving circuit that detects transmitting coil current to determine the change in load on the receiving coil;

wherein the battery device changes the receiving coil load corresponding to the data to be sent, and the charging stand data receiving circuit detects the change in load to determine the data sent from the battery device.

14. The charging stand and battery device as cited in claim 13 wherein the battery device data transmission circuit is provided with a switching device that open circuits the load on the receiving coil.

15. The charging stand and battery device as cited in claim 13 wherein the data transmission circuit is provided with a switching device connected in parallel with the receiving coil, and this switching device is switched from OFF to ON to make a closed circuit around the receiving coil and reduce the load resistance.

16. The charging stand and battery device as cited in claim 13 wherein an AC adapter connected to the charging stand is provided, a plurality of charging stands are connected to that AC adapter, and when batteries set in a given charging stand become fully charged, the AC adapter is switched to another charging stand to sequentially supply power to a plurality of charging stands from a single AC adapter and sequentially charge batteries contained in the battery device set in each charging stand.

17. The charging stand and battery device as cited in claim 16 wherein the charging stand, which charges battery device batteries first, is provided with an input switch, which controls power supplied to the charging stand that will charge batteries next, and when batteries in the battery device become fully charged, the input switch is switched ON to supply power from the AC adapter to the next charging stand.

18. The charging stand and battery device as cited in claim 17 wherein the charging stand is provided with a power supply circuit that converts input power to AC power to supply the transmitting coil, and an output terminal connected to the input-side of the power supply circuit through the input switch;

when battery device batteries become fully charged, the power supply circuit is switched OFF and the input switch is switched ON to output the input power through the output terminal and supply AC adapter power to the next charging stand.

19. The charging stand and battery device as cited in claim 13 wherein the data transmission circuit holds the switching device in the OFF state and briefly switches it ON in pulse fashion to transmit a standby for charging condition to the charging stand on the transmitting coil side.

20. The charging stand and battery device as cited in claim 13 wherein the switching device is held continuously in the OFF state for a prescribed time interval, and when this condition is detected, power transmission from the transmitting coil to the receiving coil is stopped.

21. The charging stand and battery device as cited in claim 13 wherein the battery device contains a magnet, the charging stand contains a Hall-effect integrated circuit (IC) in a position opposite the battery device magnet, and the Hall-effect IC detects the battery device to establish conditions for power transmission from the transmitting coil to the receiving coil.

22. A charging stand capable of non-contact charging of a battery device having a receiving coil, the charging stand comprising:

a transmitting coil that can supply AC power to the receiving coil; and

a data receiving circuit that detects transmitting coil current to determine changes in receiving coil load;

wherein with the battery device receiving coil in close proximity to the transmitting coil, data sent from the battery device to the charging stand can be detected by changing the receiving coil load according to the data to be sent from the battery device to the charging stand and by detecting the change in load with the data receiving circuit of the charging stand.

23. A battery device capable of being charged in a non-contact fashion using a charging stand having a transmitting coil comprising:

a receiving coil to receive AC power supplied from the charging stand transmitting coil; and

a data transmission circuit that changes the receiving coil load according to data to be sent to the charging stand;

wherein with the receiving coil in close proximity to the charging stand transmitting coil, the data transmission circuit changes the receiving coil load according to data to be sent to the charging stand, and the load changes are detected at the charging stand side to allow data to be sent from the battery device to the charging stand.