Detector, power transmitter, power receiver, power feed system, and detection method

• US 10,250,080 B2
• Filed: 03/31/2016
• Issued: 04/02/2019
• Est. Priority Date: 03/31/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Murakami, Tomomichi, Yoshino, Yoshitaka
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): Mourad, Rasem
• Application Number:
  US15/087,542
• Publication Number:
  US 20160261149A1
• Time in Patent Office: 1,097 Days
• CPC Class Codes: G01R 27/2611 Measuring inductance
• CPC Class Codes: G01V 3/10 using induction coils
• 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 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• 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

Abstract

There are provided a detector and the like that are capable of conveniently detecting conductor or a circuit including a coil. The detector includes a detecting section that determines a Q value or a degree of variation thereof in a circuit including a coil capable of electromagnetic coupling with an external object and that performs detection concerning a state of the electromagnetic coupling with the external object based on a determined result.

Claims

1. A detector, comprising:

detection circuitry configured to;

send a signal to an external object,

receive a response to the signal,

determine whether communication with the external object is possible, based on whether the response to the signal is received,

determine, in respective ones of a first case where communication with the external object is possible and a second case where nothing is present in the vicinity of the resonance circuit, a Q-value of a resonance circuit including a coil, or a degree of variation of the Q-value of the resonance circuit, the Q-value being based on a voltage or an impedance, and

determine whether a foreign object is present in a vicinity of the coil, based on the determination of the Q-value or degree of variation of the Q-value.

2. The detector according to claim 1, wherein the resonance circuit further comprises a capacitor electrically connected with the coil in series, and the Q-value is a ratio of a first voltage across the coil to a second voltage across the coil and the capacitor.

3. The detector according to claim 1, the detection circuitry comprising an arithmetic processing section configured to calculate the Q-value, and output a calculation result.

4. The detector according to claim 1, the detection circuitry comprising a rectifier configured to convert an alternating current signal from the resonance circuit to a direct current signal.

5. The detector according to claim 1, the detection circuitry comprising an analog-to-digital converter configured to convert an analog signal from the resonance circuit to a digital signal.

6. The detector according to claim 1, wherein the detection circuitry is configured to determine whether the foreign object is present by comparing the Q-value or the degree of variation of the Q-value to a predetermined value.

7. The detector according to claim 6, wherein the predetermined value is a threshold that corresponds to a reference Q-value.

8. The detector according to claim 1, wherein the detection circuitry is configured to selectively allow a power transmission between the resonance circuit and the external object.

9. The detector according to claim 1, wherein the detection circuitry is configured to:

compare the Q-value or the degree of variation of the Q-value to a predetermined value; and

based on a result of the comparison, allow the power transmission between the resonance circuit and the external object.

10. The detector according to claim 1, wherein the detection circuitry is configured to:

compare the Q-value or the degree of variation of the Q-value to a predetermined value; and

based on a result of the comparison, not allow the power transmission between the resonance circuit and the external object.

11. A power transmission device, comprising:

a resonance circuit including a coil; and

detection circuitry configured to;

send a signal to an external object,

receive a response to the signal,

determine whether communication with the external object is possible, based on whether the response to the signal is received,

determine, in respective ones a first case where communication with the external object is possible and in a second case where nothing is present in the vicinity of the resonance circuit, a Q-value of the resonance circuit, or a degree of variation of the Q-value of the resonance circuit, the Q-value being based on a voltage or an impedance,

determine whether a foreign object is present in a vicinity of the coil, based on the determination of the Q-value or degree of variation of the Q-value.

12. The power transmission device according to claim 11, wherein the resonance circuit further comprises a capacitor electrically connected with the coil in series, and the Q-value is a ratio of a first voltage across the coil to a second voltage across the coil and the capacitor.

13. The power transmission device according to claim 11, further comprising an arithmetic processing section configured to calculate the Q-value, and output a calculation result to the detection circuitry.

14. The power transmission device according to claim 11, further comprising a rectifier configured to convert an alternating current signal from the resonance circuit to a direct current signal.

15. The power transmission device according to claim 11, further comprising an analog-to-digital converter configured to convert an analog signal from the resonance circuit to a digital signal.

16. The power transmission device according to claim 11, wherein the detection circuitry is configured to determine whether the foreign object is present by comparing the Q-value or the degree of variation of the Q-value to a predetermined threshold Q-value.

17. The power transmission device according to claim 16, wherein the predetermined threshold Q-value corresponds to a Q-value in a case where the object is not present.

18. The power transmission device according to claim 11, wherein the detection circuitry is configured to selectively allow a power transmission between the resonance circuit and the external object.

19. The power transmission device according to claim 18, wherein the detection circuitry is configured to, in a case where the communication is possible, allow the power transmission between the resonance circuit the external object.

20. The power transmission device according to claim 18, wherein the detection circuitry is configured to, in a case where the communication is not possible, prevent the power transmission between the resonance circuit and the external object.

21. A detector, comprising:

detection circuitry configured to;

send a signal to an external object,

receive a response to the signal,

determine whether communication with the external object is possible, based on whether the response to the signal is received,

determine, in respective ones of a first case where communication with the external object is possible and a second case where nothing is present in the vicinity of the resonance circuit, a Q-value of a resonance circuit including a coil, or a degree of variation of the Q-value of the resonance circuit, the Q-value being based on a voltage or an impedance,

compare the Q-value or the degree of variation of the Q-value to a predetermined value,

determine whether a foreign object is present in a vicinity of the coil, based on a result of the comparison, and

based on the result of the comparison, determine whether to allow the power transmission between the resonance circuit and the external object.