DEVICE HOUSING A BATTERY AND CHARGING PAD

• US 20100315039A1
• Filed: 06/14/2010
• Published: 12/16/2010
• Est. Priority Date: 06/15/2009
• Status: Active Grant

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: TOYA, Shoichi, TERAO, Kyozo
• Granted Patent: US 8,410,751 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/12 of the resonant type
• 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

Abstract

A device housing a battery 50 includes a receiving coil 51, and a charging pad 10 includes a transmitting coil 11 that magnetically couples with, and supplies charging power to the receiving coil 51. The device further includes a modulator circuit 61 that changes the impedance of the receiving coil according to internal battery 52 data. The charging pad further includes a detection circuit 17 that detects receiving coil impedance changes to detect the battery data. The modulator circuit 61 has a load circuit 62 that is connected in parallel with the receiving coil 51 and has a series-connected switching device 64 and impedance modulating capacitor 63, and a control circuit 65 that switches the load circuit 62 switching device 64 ON and OFF according to the battery data. The modulator circuit 61 switches the switching device 64 ON and OFF to transmit battery data to the charging pad 10.

Claims

1. A device housing a battery and charging pad comprising:

a device housing a battery having an receiving coil that supplies charging power to the internal battery; and

a charging pad having a transmitting coil that magnetically couples with the receiving coil in the device housing a battery and supplies charging power;

wherein

the device housing a battery is provided with a modulator circuit that modulates the impedance of the receiving coil with internal battery information;

the charging pad is provided with a detection circuit that detects battery information via the transmitting coil by detecting receiving coil impedance changes made by the modulator circuit;

the modulator circuit is provided with a load circuit connected in parallel with the receiving coil and having a series-connected impedance modulating capacitor and switching device, and a control circuit that switches the load circuit switching device ON and OFF with battery information; and

the modulator circuit switches the switching device ON and OFF to transmit battery information to the charging pad.

2. The device housing a battery and charging pad as cited in claim 1 wherein the detection circuit detects receiving coil impedance changes to detect battery information by voltage level changes in the transmitting coil.

3. The device housing a battery and charging pad as cited in claim 1 wherein the detection circuit detects receiving coil impedance changes to detect battery information by current level changes in the transmitting coil.

4. The device housing a battery and charging pad as cited in claim 1 wherein the detection circuit detects receiving coil impedance changes to detect battery information by changes in the current-voltage phase relation in the transmitting coil.

5. The device housing a battery and charging pad as cited in claim 1 wherein the detection circuit detects receiving coil impedance changes to detect battery information by transmission efficiency changes in the transmitting coil.

6. The device housing a battery and charging pad as cited in claim 1 provided with a series capacitor connected in series with the receiving coil.

7. The device housing a battery and charging pad as cited in claim 1 wherein the device housing a battery transmits battery information to the charging pad that includes battery voltage during charging.

8. The device housing a battery and charging pad as cited in claim 1 wherein the device housing a battery transmits battery information to the charging pad that includes battery charging current.

9. The device housing a battery and charging pad as cited in claim 1 wherein the device housing a battery transmits battery information to the charging pad that includes battery temperature during charging.

10. The device housing a battery and charging pad as cited in claim 8 wherein the device housing a battery transmits battery information to the charging pad that includes the serial number of the battery being charged.

11. The device housing a battery and charging pad as cited in claim 10 wherein the device housing a battery transmits battery information to the charging pad that includes the allowable charging current that sets the charging current for the battery being charged.

12. The device housing a battery and charging pad as cited in claim 1 wherein the device housing a battery transmits battery information to the charging pad that includes the allowable temperature that controls charging.

13. The device housing a battery and charging pad as cited in claim 1 wherein the device housing a battery is provided with a rectifying circuit that rectifies AC power induced in the receiving coil from the transmitting coil, and the load circuit is connected to the input-side of the rectifying circuit.

14. The device housing a battery and charging pad as cited in claim 13 wherein the rectifying circuit is a synchronous rectifying circuit.

15. The device housing a battery and charging pad as cited in claim 13 wherein the rectifying circuit is a diode-bridge circuit.

16. The device housing a battery and charging pad as cited in claim 1 wherein the charging pad is provided with a case having a charging region where a device housing a battery can be placed in a removable manner, a moving mechanism that moves the transmitting coil to a position in close proximity to the receiving coil, and a position detection controller that determines the position of the receiving coil in the device housing a battery placed on the charging region and controls the moving mechanism to move the transmitting coil close to the receiving coil in the device housing a battery;

the position detection controller is provided with position detection coils fixed to a top plate, a detection signal generating circuit that supplies position detection signals to the position detection coils, a receiving circuit that receives echo signals output from the receiving coil to the position detection coils due to excitation of the receiving coil by position detection signals supplied to the position detection coils from the detection signal generating circuit, and a discrimination circuit that determines receiving coil position from the echo signals received by the receiving circuit;

the device housing a battery is provided with a rectifying circuit connected to the receiving coil that converts AC induced in the receiving coil to DC to supply the internal battery with charging power, and a series capacitor connected in series with the receiving coil to input receiving coil AC to the rectifying circuit; and

when the position detection controller issues position detection signals, the modulator circuit control circuit switches the switching device ON to connect the impedance modulating capacitor to the receiving coil.

17. The device housing a battery and charging pad as cited in claim 1 wherein the load circuit is provided with a pair of series-connected switching devices, and an impedance modulating capacitor connected in series with each switching device;

the connection node between the pair of switching devices is connected to the ground line; and

the pair of switching devices is simultaneously controlled ON and OFF by the control circuit.

18. The device housing a battery and charging pad as cited in claim 17 wherein the device housing a battery is configured with a single capacitor serving as both the series capacitor and the impedance modulating capacitor;

and the switching device switches the capacitor to act as the series capacitor or the impedance modulating capacitor.

19. The device housing a battery and charging pad as cited in claim 18 wherein the capacitor is connected between the receiving coil and the rectifying circuit, and the switching device implements a shorting circuit that short circuits the rectifying circuit side of the capacitor.

20. The device housing a battery and charging pad as cited in claim 1 wherein the switching device is a photo-transistor that switches ON and OFF via light.