CONTACTLESS BATTERY CHARGER, ELECTRONIC DEVICE, BATTERY PACK, AND CONTACTLESS CHARGING SYSTEM

• US 20130057206A1
• Filed: 11/02/2012
• Published: 03/07/2013
• Est. Priority Date: 11/08/2006
• Status: Active Grant

• Current Assignee: Panasonic Automotive Systems Company of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Takahashi, Hiroyuki, Oku, Hiroyuki, Oshimi, Masanori
• Granted Patent: US 9,407,109 B2
• Time in Patent Office: Days
• US Class Current: 320/108
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/446 Initial charging measures
• CPC Class Codes: H01M 10/448 End of discharge regulating measures
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• 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: Y02E 60/10 Energy storage using batteries

Abstract

A contactless charging system is made up of an electronic device and a contactless charger 200 that recharges the electronic device in a contactless manner. The electronic device transmits a full charge command indicating completion of charge. Upon receipt of the full charge command, the contactless charger shifts to a charge stop state in which charge of the electronic device is not performed. In the charge stop state, the contactless charger generates a load check signal for checking whether or not the electronic device is placed in the contactless charger in a rechargeable state, and transmits the signal. Further, the contactless charger also generates a charge restart check command for checking whether or not the electronic device requests recharge in a charge stop state, and transmits the command.

Claims

1. A contactless charger for charging, in a contactless manner, an electronic device using a secondary battery as a power source, the charger comprising:

a transceiving section that receives from the electronic device a full charge command indicating completion of recharge; and

a control section that shifts, upon receipt of the full charge command, the contactless charger to a charge stop state in which charge of the electronic device is not performed,

wherein the control section intermittently generates, in the charge stop state, a load check signal for checking whether or not the electronic device is placed on the contactless charger in a rechargeable manner, and the transceiving section sends the load check signal,

wherein the control section further intermittently generates, in the charge stop state, a charge restart check command for checking whether or not the electronic device requires recharge, and the transceiving section transmits the charge restart check command,

wherein the control section intermittently generates the load check signal and the charge restart check command, and

wherein time intervals at which the charge restart check command is generated are larger than time intervals at which the load check signal is generated.

2. The contactless charger according to claim 1, wherein

when it is ascertained by the load check signal that the electronic device is placed, the control section maintains the contactless charger in a charge stop state, and

when it is ascertained by the load check signal that the electronic device is not placed, the control section shifts the contactless charger to an initial state achieved immediately after activation of a power source.

3. The contactless charger according to claim 1, wherein the transceiving section includes a coil that transmits power for recharging the electronic device;

and the contactless charger further comprises a modulation section that superimposes the load check signal and the charge restart check command on power and that modulates the power.

4. The contactless charger according to claim 1, wherein the transceiving section includes a coil that transmits power for recharging the electronic device;

and the control section determines, based on a phase change in an electric current developing in the coil, that the electronic device is placed.

5. The contactless charger according to claim 1, wherein, when the transceiving section receives a recharge command indicating that the electronic device requests recharge in response to the charge restart check command, the control section shifts the contactless charger to a power transfer state;

and, when the transceiving section does not receive the recharge command in response to the charge restart check command, the control section holds the contactless charger in a charge stop state.

6. The contactless charger according to claim 5, wherein the transceiving section includes a coil for transmitting power for charging the electronic device, and the control section determines the full charge command and the recharge command based on a phase change in an electric current developing in the coil.

7. An electronic device that uses as a power source a secondary battery which can be charged by the contactless charger according to claim 1.

8. The electronic device according to claim 7 further comprising:

a control section that generates a full charge command indicating that the contactless charger is shifted to a charge stop state in which charging of the electronic device is not performed in response to completion of charge of the secondary battery; and

a transceiving section for transmitting the full charge command to the contactless charger,

wherein, when the transceiving section receives from the contactless charger the charge restart check command for checking whether or not the electronic device requests recharge in the charge stop state, the control section checks whether or not the secondary battery requests recharge; and

, when the recharge is requested, the control section generates the recharge command indicating a request for recharge, and the transceiving section transmits the recharge command to the contactless charger.

9. An electronic device according to claim 7, wherein the transceiving section includes a coil that receives from the contactless charger power for charging the secondary battery;

and the electronic device further comprises a modulation section that superimposes the full charge command and the recharge command on an electric current generated by the electronic device and that modulates the electric current.

10. The electronic device according to claim 9, wherein the modulation section differentiates the full charge command and the recharge command in terms of a difference in data sequence.

11. A battery pack attachable to an electronic device that uses, as a power source, a secondary battery which can be charged by a contactless charger for effecting charge in a contactless fashion,

wherein the electronic device includes a control section that generates, in response to completion of charge of the secondary battery, a full charge command indicating that the contactless charger is shifted to a charge stop state in which the electronic device is not charged, and

wherein the battery pack includes:

the secondary battery; and

a coil for transmitting the full charge command to the contactless charger.

12. An electronic device that allows attachment of the battery pack according to claim 11.

13. A contactless charging system including an electronic device and a contactless charger for charging the electronic device in a contactless fashion, wherein

the electronic device transmits a full charge command indicating that charge of the electronic device is completed;

the contactless charger shifts to a charge stop state in which charge of the electronic device is not performed, upon receipt of the full charge command;

the contactless charger intermittently generates, in the charge stop state, a load check signal for checking whether or not the electronic device is placed on the contactless charger in a state where the electronic device can be recharged, and transmits the load check signal;

the contactless charger further generates, in the charge stop state, a charge restart check command for checking whether or not the electronic device requests recharge, and transmits the command; and

wherein time intervals at which the charge restart check command is generated are larger than time intervals at which the load check signal is generated.