Electronic device, control method for electronic device, recharge-rate estimating method for secondary battery, and charging control method for secondary battery

• US 6,316,909 B1
• Filed: 01/05/2000
• Issued: 11/13/2001
• Est. Priority Date: 03/24/1998
• Status: Expired due to Term

• Current Assignee: Chamiraux Management LLC
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Honda, Katsuyuki, Hayakawa, Motomu, Kosuda, Tsukasa, Aoshima, Ichiro
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/424,204
• Time in Patent Office: 678 Days
• Field of Search: 320/108, 320/129, 320/132, 320/156, 320/157, 320/160, 320/162, 320/165, 968/888, 968/503, 968/889, 968/892, 362/204
• US Class Current: 320/108
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G04C 10/00 Arrangements of electric power supplies in time pieces circuits G04G19/00; mounting, assembling of components of electromechanical watches G04C3/008, of electronic watches G04G17/00
• CPC Class Codes: H02J 50/005 Mechanical details of housing or structure aiming to accommodate the power transfer means, e.g. mechanical integration of coils, antennas or transducers into emitting or receiving devices
• CPC Class Codes: H02J 50/10 using inductive coupling
• 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 7/0044 specially adapted for holding portable devices containing batteries H02J7/0045 takes precedence

Abstract

A first circuit having a first coil electrically charges a second circuit having a second coil through electromagnetic coupling of the two coils. When data signals are to be transferred between the first and second circuits, signal transfer is started only after the second circuit has been charged for a predetermined period of time. The position relationship between the coils is also detected, and a charging/transfer selector changes a duty ratio between charge transfer and data transfer in accordance with the detected result. The charge is transferred in an intermittent manner, and the charging rate is adjusted according to the difference between the voltage of a secondary battery observed during a charging phase and the voltage of the secondary battery observed a certain time after interruption of the charging phase, or vice versa.

Claims

1. An electronic device having a first device and a second device, said electronic device comprising:

charging/signal transfer means for charging the second device by the first device from a side of the first device to a side of the second device, and for transferring a signal between said first device and said second device; and

charging/signal transfer control means for starting transferring of the signal by said charging/signal transfer means after charging the second device by said charging/signal transfer means for a predetermined period.

3. An electronic device according to claim 1 or 2, wherein said charging/signal transfer control means transmits, prior to the signal transfer, a communication start command for informing a start of communication.

4. An electronic device according to claim 1 or 2, wherein when said charging/signal transfer means transfers the signal, said charging/signal transfer means is operated in accordance with a driving frequency higher than a driving frequency when said charging/signal transfer means is not transferring the signal.

5. An electronic device according to claim 1 or 2, wherein said charging/signal transfer control means alternately controls charging and transferring of the signal by said charging/signal transfer means.

2. An electronic device having a first device and a second device, said electronic device comprising:

charging/signal transfer means for charging the second device by the first device from a side of the first device to a side of the second device by one of electromagnetic coupling and electromagnetic induction, for transferring a signal between the first device and said second device; and

charging/signal transfer control means for starting transferring of the signal by said charging/signal transfer means after charging the second device by said charging/signal transfer means for a predetermined period.

6. An electronic device having a first device and a second device for transferring at least one of power and signals through electromagnetic coupling or electromagnetic induction between a first coil disposed in said first device and a second coil disposed in said second device, said first and second coils being disposed in opposing positions, said electronic device comprising:

an initiation input receiver for receiving a start signal causing said first coil to generate an external magnetic field;

a signal generator controlling a power transfer cycle in which a power signal is transmitted through said first coil to said second device during a first phase and status data from said second device is expected during a second phase, said status data being characteristic of the amount of power stored in said second device, said signal generator responding to a lack of status data from said second device by reinitiating said power transfer cycle up to a predetermined number of power transfer cycles;

a control circuit issuing a warning signal in response to the elapse of said predetermined number of power transfer cycles without receiving said status data from said second device.

7. The electronic device of claim 6, wherein said first and second phase have regular intervals such that said predetermined number of power transfer cycles constitute a predetermined wait period during which no status data is received from said second device without causing said control circuit to issue said warning signal.

8. An electronic device according to claim 6, further comprising a status transmission circuit effective for transmitting said status data only when the amount of power stored in said second device is above a predetermined threshold value.

16. An electronic device according to claim 6, further comprising:

signal transfer means for transferring a signal between the first and second devices;

rectifying means for rectifying a signal flowing through the second coil; and

electricity accumulating means for accumulating the signal rectified by said rectifying means.

9. An electronic device having a first device and a second device for transferring at least power or signals through coils, said electronic device comprising:

a first coil disposed in said first device;

a second coil disposed in said second device and adapted to be electromagnetically coupled with said first coil;

a signal supply circuit to supply a signal to said first coil to generate an external magnetic field;

a current detecting circuit to detect a current flowing through said second coil in accordance with said external magnetic field;

an interrogator circuit disposed in said first device and transmitting an query signal requesting status information of said current flow in said second coil, said current detecting circuit responding to said query signal only when the value of said current flow is above a predetermined threshold value; and

a position determining circuit to determine a positional relationship between said first and second coils based on the number of query signals transmitted without a corresponding response from said current detecting circuit.

10. An electronic device for transferring at least power or signals to a partner device through electromagnetic coupling or electromagnetic induction between a first coil disposed in said electronic device and a second coil disposed in the partner device, the first and second coils being disposed in opposing positions, said electronic device comprising:

signal supply means for supplying a signal to the first coil;

position determining means for determining a positional relationship between the first and second coils upon receiving a command from said partner device after said signal supply means has supplied the signal to the first coil; and

informing means for informing the positional relationship determined by said position determining means, wherein when said position determining means does not receive the command from the partner device for a certain period, said informing means informs an absence of said partner device.

11. An electronic device according to claim 10, wherein when the positional relationship between the first and second coils is determined to be in predetermined relation by said position determining means, said informing means informs the determination result.

12. An electronic device according to claim 10, wherein the first coil disposed comprises an air-core type coil.

13. A position detecting method for an electronic device having a first device and a second device for transferring at least power or signals through electromagnetic coupling or electromagnetic induction between a first coil disposed in the first device and a second coil disposed in the second device, said first and second coils being disposed in opposing positions, said method comprising the steps of:

supplying a signal to said first coil in said first device to generate an external magnetic field;

submitting status requests for information of a current flow through said second coil;

detecting said current flowing through said second coil in said second device in accordance with said external magnetic field and responding to said status requests only when said current flow is above a predetermined threshold;

determining a positional relationship between the first and second coils in accordance with the response and lack of response to said status requests.

14. An electronic device having a first device and a second device for transferring at least power or signals through electromagnetic coupling or electromagnetic induction between a first coil disposed in the first device and a second coil disposed in the second device, the first and second coils being disposed in opposing positions, said electronic device comprising:

signal supply means for supplying a first signal to the first coil to generate an external magnetic field;

state detecting means for detecting an electrical state of said second coil in accordance with the external magnetic field;

control means for controlling said first signal supplied by said signal supply means in accordance with a result detected by said state detecting means;

signal transfer means for transferring a second signal between the first and second devices, wherein said signal transfer means transfers the second signal after said signal supply means has supplied the first signal for a predetermined period;

rectifying means for rectifying a power signal flowing through the second coil; and

electricity accumulating means for accumulating the power signal rectified by said rectifying means.

15. An electronic device according to claim 6 or 14, wherein the electrical state is a current state or a voltage state.

17. An electronic device according to claim 14, wherein said signal transfer means transfers the second signal after a communication start command for informing the start of communication has been transmitted.

18. An electronic device according to claim 14, wherein when transferring the second signal between the first and second devices, operation is performed in accordance with a higher frequency than a frequency when not transferring the second signal.

21. An electronic device according to claim 14, wherein a result detected by said current detecting means is transferred by said signal transfer means.

22. An electronic device according to claim 6 or 14, wherein the second device comprises a portable type device.

23. An electronic device according to claim 6 or 14, wherein the first or second coil comprises an air-core type coil.

19. An electronic device having a first device and a second device for transferring at least power or signals through electromagnetic coupling or electromagnetic induction between a first coil disposed in the first device and a second coil disposed in the second device, the first and second coils being disposed in opposing positions, said electronic device comprising:

signal supply means for supplying a first signal to the first coil to generate an external magnetic field;

state detecting means for detecting an electrical state of said second coil in accordance with the external magnetic field;

control means for controlling said first signal supplied by said signal supply means in accordance with a result detected by said state detecting means;

signal transfer means for transferring a second signal between the first and second devices;

rectifying means for rectifying a power signal flowing through the second coil; and

electricity accumulating means for accumulating the power signal rectified by said rectifying means;

wherein said control means alternately controls execution of the first signal supplied by said signal supply means and the second signal transferred by said signal transfer means.

20. An electronic device having a first device and a second device for transferring at least power or signals through electromagnetic coupling or electromagnetic induction between a first coil disposed in the first device and a second coil disposed in the second device, the first and second coils being disposed in opposing positions, said electronic device comprising:

signal supply means for supplying a first signal to the first coil to generate an external magnetic field;

state detecting means for detecting an electrical state of said second coil in accordance with the external magnetic field;

control means for controlling said first signal supplied by said signal supply means in accordance with a result detected by said state detecting means;

signal transfer means for transferring a second signal between the first and second devices;

rectifying means for rectifying a power signal flowing through the second coil; and

electricity accumulating means for accumulating the power signal rectified by said rectifying means;

wherein when the positional relationship between the first and second coils is determined to be in a predetermined relation, said control means changes a duty ratio between the signal supplied by said signal supply means and the signal transferred by said signal transfer means.

24. An electronic device for transferring at least power or signals to a partner device through electromagnetic coupling or electromagnetic induction between a first coil disposed in said electronic device and a second coil disposed in the partner device, the first and second coils being disposed in opposing positions, said electronic device comprising:

signal supply means for supplying a signal to the first coil; and

control means for controlling the signal supplied by said signal supply means upon receiving a command from the partner device after said signal supply means has supplied the signal to the first coil;

wherein upon receiving no commands from the partner device for a predetermined period, said control means terminates the signal supplied by said signal supply means.

25. An electronic device according to claim 24, wherein upon receiving, from the partner device, a command informing that the charging is not required, said control means terminates the signal supplied by said signal supply means.

26. An electronic device according to claim 24, wherein when the communication start command is transmitted from the partner device, said signal transfer means transfers the signal.

27. An electronic device comprising:

charging means for charging a secondary battery in an intermittent manner;

first voltage detecting means for detecting a voltage of the secondary battery after a predetermined time has lapsed from interruption of the charging by said charging means; and

estimating means for estimating a recharge rate of the secondary battery in accordance with the voltage detected by said voltage detecting means.

28. An electronic device according to claim 27, further comprising second voltage detecting means for detecting a voltage of said secondary battery during the charging by said charging means;

and

subtracting means for subtracting the voltage detected by said first voltage detecting means from the voltage detected by said second voltage detecting means;

said estimating means estimating a recharge rate of the secondary battery from a voltage difference calculated by said subtracting means.

29. An electronic device according to claim 28, further comprising determining means for determining whether the recharge rate estimated by said estimating means reaches to a predetermined value.

30. An electronic device according to claim 29, wherein if the recharge rate reaches the predetermined value as determined by said determining means, said charging means terminates charging by said charging means.

31. An electronic device comprising:

a charging circuit to charge a secondary battery in an intermittent manner;

a voltage detecting circuit to detect a voltage of the secondary battery after a predetermined time has lapsed from interrupting of the charging by said charging circuit; and

an estimating circuit to estimate a recharge rate of the secondary battery in accordance with the voltage detected by said voltage detecting circuit.

32. A recharge-rate estimating method for a secondary battery, comprising the steps of:

(a) charging the secondary battery in an intermittent manner;

(b) interrupting the charging of the secondary battery in step (a);

(c) detecting a voltage of the secondary battery after a certain time has lapsed from the interruption of the charging in step (b); and

(d) estimating a recharge rate of the secondary battery in accordance with the detected voltage in step (c).

33. An electronic device in which a charging device transfers power to a charged device through electromagnetic coupling or electromagnetic induction between a first coil disposed in said electronic device and a second coil disposed in the charged device, the first and second coils being disposed in opposing positions and the charged device charges the transferred power into a secondary battery in an intermittent manner, said electronic device comprising:

first voltage detecting means for detecting a voltage of the secondary battery after a predetermined time has lapsed from interruption of the charging;

transfer means for transferring the voltage detected by said first voltage detecting means or an estimated result based on the voltage detected by said first voltage detecting means through the first and second coils; and

control means for controlling the charging of the secondary battery in accordance with a result transferred by said transfer means.

34. An electronic device according to claim 33, wherein said control means alternately controls the charging by said charging means and transferring of the signal by said signal transfer means, and also controls a duty ratio between the charging by said charging means and the signal transferred by said signal transfer means in accordance with the result transferred by said transfer means.

35. An electronic device according to claim 33, wherein the charged device comprises a portable type device.

36. An electronic device according to claim 33, wherein the first or second coil comprises an air-core type coil.

37. An electronic system in which a charging device transfers power to a charged device through electromagnetic coupling or electromagnetic induction between a first coil disposed in said charging device and a second coil disposed in said charged device, said first and second coils being disposed in opposing positions and said charged device applying the transferred power to a secondary battery in an intermittent manner, said electronic system comprising:

a first voltage detecting circuit for detecting a voltage of the secondary battery after a predetermined time has lapsed from interruption of the charging, said predetermined time being selected such that the detected voltage includes a voltage sub-component due to the internal resistance of said secondary battery;

a transfer circuit for transferring the voltage detected by said first voltage detecting circuit or an estimated result based on the voltage detected by said first voltage detecting means through said first and second coils; and

a control circuit for controlling the charging in accordance with said voltage sub-component due to the internal resistance of said secondary battery.

38. A charging control method for an electronic system in which a charging device transfers power to a charged device through electromagnetic coupling or electromagnetic induction between a first coil disposed in said electronic device and a second coil disposed in said charged device, said first and second coils being disposed in opposing positions and said charged device stores the transferred power into a secondary battery, said method comprising the steps of:

(a) interrupting the charging of said secondary battery;

(b) detecting a voltage of said secondary battery after a predetermined time has lapsed from the interruption of the charging in step (a), said predetermined time being selected such that the detected voltage includes a voltage sub-component due to the internal resistance of said secondary battery;

(c) transferring the detected voltage in step (b) or an estimated result based on the detected voltage in step (b) through the first and second coils; and

(d) controlling the charging of the secondary battery in accordance with said voltage sub-component due to the internal resistance of said secondary battery.

39. An electronic device comprising:

charging means for charging a secondary battery in an intermittent manner;

first voltage detecting means for detecting a first voltage of the secondary battery at a time immediately after interrupting of charging by said charging means;

second voltage detecting means for detecting a second voltage of the secondary battery at a time immediately before resumption of charging by said charging means after interrupting of charging by said charging means; and

estimating means for estimating a recharge rate of the secondary battery in accordance with a voltage difference between the first voltage of the secondary battery detected by said first voltage detecting means and the voltage of said secondary battery detected by said second voltage detecting means.

40. An electronic device comprising:

a charging circuit to charge a secondary battery in an intermittent manner;

a first voltage detecting circuit to detect a first voltage of the secondary battery at a time immediately after interrupting of charging by said charging circuit;

a second voltage detecting circuit to detect a second voltage of the secondary battery at a time immediately before resumption of charging by said charging circuit after interrupting of charging by said charging circuit; and

an estimating circuit to estimate a recharge rate of the secondary battery in accordance with a voltage difference between the first voltage of said secondary battery detected by said first voltage detecting circuit and the second voltage of said secondary battery detected by said second voltage detecting circuit.

41. A recharge-rate estimating method for an electronic device, comprising the steps of:

(a) charging a secondary battery;

(b) interrupting the charging of the secondary battery in step (a);

(c) resuming the charging of the secondary battery after step (b);

(d) detecting an interruption voltage provided as a voltage of the secondary battery at the time immediately after interruption of the charging in step (b);

(e) detecting a resumption voltage of the secondary battery at the time immediately before resumption of the charging in step (c); and

(f) estimating a recharge rate of the secondary battery in accordance with a voltage difference between the interruption voltage and resumption voltage.

42. An electronic device comprising:

charging means for charging a secondary battery in an intermittent manner;

first voltage detecting means for detecting a first voltage of the secondary battery at a time immediately before resumption of charging by said charging means after interruption of charging by said charging means;

second voltage detecting means for detecting a second voltage of the secondary battery at a time immediately after resumption of the charging by said charging means; and

estimating means for estimating a recharge rate of the secondary battery in accordance with a voltage difference between the first voltage of the secondary battery detected by said first voltage detecting means and the second voltage of the secondary battery detected by said second voltage detecting means.

43. An electronic device comprising:

a charging circuit to charge a secondary battery in an intermittent manner;

a first voltage detecting circuit to detect a first voltage of the secondary battery at a time immediately before resumption of charging by said charging circuit after interruption of charging by said charging circuit;

a second voltage detecting circuit to detect a second voltage of the secondary battery at a time immediately after resumption of the charging by said charging circuit; and

an estimating circuit to estimate a recharge rate of the secondary battery in accordance with a voltage difference between the first voltage of said secondary battery detected by said first voltage detecting circuit and the second voltage of said secondary battery detected by said second voltage detecting circuit.

44. A recharge-rate estimating method for an electronic device, comprising the steps of:

(a) charging a secondary battery;

(b) interrupting the charging of the secondary battery of step (a);

(c) resuming the charging of the secondary battery after step (b);

(d) detecting a just-before-resumption voltage of the secondary battery at a time immediately before resumption of the charging of step (c);

(e) detecting a just-after-resumption voltage of the secondary battery at the time immediately after resumption of the charging of step (c); and

(f) estimating a recharge rate of the secondary battery in accordance with a voltage difference between the just-before-resumption voltage detected in step (d) and the just-after-resumption voltage detected in step (e).

45. An electronic device having a first device and a second device, said electronic device comprising:

a charge/signal transfer circuit for charging of the second device by the first device from a side of the first device to a side of the second device, and for transferring a signal between said first device and said second device; and

a charge/signal transfer controller for starting the transfer of said signal by said charge/signal transfer circuit after charging of the second device by said charge/signal transfer circuit for a predetermined period.

46. An electronic device having a first device and a second device, said electronic device comprising:

a charge/signal transfer circuit for charging of the second device by the first device from a side of the first device to a side of the second device by one of electromagnetic coupling and electromagnetic induction, and for transferring a signal between the first device and said second device; and

a charge/signal transfer controller for starting transfer of said signal by said charge/signal transfer circuit after charging of the second device by said charge/signal transfer circuit for a predetermined period.

47. An electronic device for transferring at least power or signals to a partner device through electromagnetic coupling or electromagnetic induction between a first coil disposed in said electronic device and a second coil disposed in the partner device, the first and second coils being disposed in opposing positions, said electronic device comprising:

a signal source for supplying a signal to the first coil;

a position detector for determining a positional relationship between the first and second coils upon receiving a command from said partner device after said signal source has supplied the signal to the first coil; and

a status transmitter for conveying the positional relationship determined by said position detector, wherein when said position detector does not receive the command from the partner device for a certain period, said status transmitter conveys an absence of said partner device.

48. An electronic device having a first device and a second device for transferring at least power or signals through electromagnetic coupling or electromagnetic induction between a first coil disposed in the first device and a second coil disposed in the second device, the first and second coils being disposed in opposing positions, said electronic device comprising:

a signal source for supplying a first signal to the first coil to generate an external magnetic field;

a state detector for detecting an electrical state of said second coil in accordance with the external magnetic field;

a controller for controlling said first signal supplied by said signal source in accordance with a result detected by said state detector;

a signal transmitter for transferring a second signal between the first and second devices, wherein said signal transmitter transfers the second signal after said signal source has supplied the first signal for a predetermined period;

a rectifier for rectifying a power signal flowing through the second coil; and

an electricity accumulating sub-circuit for accumulating the power signal rectified by said rectifier.

49. An electronic device having a first device and a second device for transferring at least power or signals through electromagnetic coupling or electromagnetic induction between a first coil disposed in the first device and a second coil disposed in the second device, the first and second coils being disposed in opposing positions, said electronic device comprising:

a signal source for supplying a first signal to the first coil to generate an external magnetic field;

a state detector for detecting an electrical state of said second coil in accordance with the external magnetic field;

a controller for controlling said first signal supplied by said signal source in accordance with a result detected by said state detector;

a signal transmitter for transferring a second signal between the first and second devices;

a rectifier for rectifying a power signal flowing through the second coil; and

an electricity accumulating sub-circuit for accumulating the power signal rectified by said rectifier;

wherein said controller alternately controls execution of the first signal supplied by said signal source and the second signal transferred by said signal transmitter.

50. An electronic device having a first device and a second device for transferring at least power or signals through electromagnetic coupling or electromagnetic induction between a first coil disposed in the first device and a second coil disposed in the second device, the first and second coils being disposed in opposing positions, said electronic device comprising:

a signal source for supplying a first signal to the first coil to generate an external magnetic field;

a state detector for detecting an electrical state of said second coil in accordance with the external magnetic field;

a signal controller for controlling said first signal supplied by said signal supply means in accordance with a result detected by said state detector;

a signal transmitter for transferring a second signal between the first and second devices;

a rectifier for rectifying a power signal flowing through the second coil; and

an electricity accumulating sub-circuit for accumulating the power signal rectified by said rectifier;

wherein when the positional relationship between the first and second coils is determined to be in a predetermined relation, said controller changes a duty ratio between the signal supplied by said signal source and the signal transferred by said signal transmitter.

51. An electronic device for transferring at least power or signals to a partner device through electromagnetic coupling or electromagnetic induction between a first coil disposed in said electronic device and a second coil disposed in the partner device, the first and second coils being disposed in opposing positions, said electronic device comprising:

a signal source for supplying a signal to the first coil; and

a controller for controlling the signal supplied by said signal source upon receiving a command from the partner device after said signal source has supplied the signal to the first coil;

wherein upon receiving no commands from the partner device for a predetermined period, said controller terminates the signal supplied by said signal source.

52. An electronic device comprising:

a charger for charging a secondary battery in an intermittent manner;

a first voltage detector for detecting a voltage of the secondary battery after a predetermined time has lapsed from interruption of the charging by said charging means; and

a rate determining circuit for determining an expected recharge rate of the secondary battery in accordance with the voltage detected by said voltage detecting means.

53. An electronic device in which a charging device transfers power to a charged device through electromagnetic coupling or electromagnetic induction between a first coil disposed in said electronic device and a second coil disposed in the charged device, the first and second coils being disposed in opposing positions and the charged device charges the transferred power into a secondary battery in an intermittent manner, said electronic device comprising:

a first voltage detector for detecting a voltage of the secondary battery after a predetermined time has lapsed from interruption of the charging;

a signal transfer circuit for transferring the voltage detected by said first voltage detecting means or an estimated result based on the voltage detected by said first voltage detecting means through the first and second coils; and

a controller for controlling the charging of the secondary battery in accordance with a result transferred by said signal transfer circuit.

54. An electronic device comprising:

a charger for charging a secondary battery in an intermittent manner;

a first voltage detector for detecting a first voltage of the secondary battery at a time immediately after interruption of charging by said charger;

a second voltage detector for detecting a second voltage of the secondary battery at a time immediately before resumption of charging by said charger after interruption of charging by said charger; and

a rate determining circuit for determining an expected recharge rate of the secondary battery in accordance with a voltage difference between the first voltage of the secondary battery detected by said first voltage detector and the voltage of said secondary battery detected by said second voltage detector.

55. An electronic device comprising:

a charger for charging a secondary battery in an intermittent manner;

a first voltage detector for detecting a first voltage of the secondary battery at a time immediately before resumption of charging by said charger after interruption of charging by said charger;

a second voltage detector for detecting a second voltage of the secondary battery at a time immediately after resumption of charging by said charger; and

a rate determining circuit for determining an expected recharge rate of the secondary battery in accordance with a voltage difference between the first voltage of the secondary battery detected by said first voltage detector and the second voltage of the secondary battery detected by said second voltage detector.