NON-CONTACT CHARGER AND NON-CONTACT CHARGING SYSTEM

• US 20080205919A1
• Filed: 02/25/2008
• Published: 08/28/2008
• Est. Priority Date: 02/28/2007
• Status: Active Grant

• Current Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Original Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Inventors: Takagi, Izumi
• Granted Patent: US 8,373,385 B2
• Time in Patent Office: Days
• US Class Current: 399/50
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/60 responsive to the presence of foreign objects, e.g. detection of living beings
• CPC Class Codes: H02J 7/0042 characterised by the mechanical construction
• CPC Class Codes: H02J 7/0044 specially adapted for holding portable devices containing batteries H02J7/0045 takes precedence
• CPC Class Codes: H04M 1/72502 with one base station connected to a single line

Abstract

A non-contact charger includes: a casing having a recessed portion in which a cordless handset is placeable; a primary coil which is provided in the casing to be opposed to the cordless handset upon placement of the cordless handset in the recessed portion of the casing; an oscillating portion which is oscillatable to generate a magnetic flux energy from the primary coil; a detecting portion which detects at least one of a current value and a voltage value in the oscillating portion; and a controller which stops a generation of the magnetic flux energy based on at least one of the current value and the voltage value detected by the detecting portion.

Claims

1. A non-contact charger comprising:

a casing having a recessed portion in which a cordless handset is placeable;

a primary coil which is provided in the casing to be opposed to the cordless handset upon placement of the cordless handset in the recessed portion of the casing;

an oscillating portion which is oscillatable to generate a magnetic flux energy from the primary coil;

a detecting portion which detects at least one of a current value and a voltage value in the oscillating portion; and

a controller which stops a generation of the magnetic flux energy based on the at least one of the current value and the voltage value detected by the detecting portion.

2. The non-contact charger according to claim 1, wherein the controller stops the generation of the magnetic flux energy in a case where the at least one of the current value and the voltage value detected by the detecting portion does not satisfy a predetermined condition.

3. The non-contact charger according to claim 2, wherein the detecting portion detects the current value as the at least one of the current value and the voltage value, and

wherein the controller determines that the current value does not satisfy the predetermined condition in a case where the current value detected by the detecting portion is smaller than a predetermined current reference value, and stops the generation of the magnetic flux energy.

4. The non-contact charger according to claim 1, wherein the controller stops the generation of the magnetic flux energy by stopping an oscillation of the oscillating portion.

5. The non-contact charger according to claim 1, further comprising a switch portion, and

wherein the controller stops the generation of the magnetic flux energy by operating the switch portion.

6. The non-contact charger according to claim 5, wherein the switch portion is provided in a portion of the oscillating portion in which a current flowing therethrough is minimized.

7. The non-contact charger according to claim 2, wherein the controller includes an energy-restarting portion which restarts the generation of the magnetic flux energy in a case where a second condition different from the predetermined condition as a first condition is satisfied after the generation of the magnetic flux energy is stopped.

8. The non-contact charger according to claim 7, wherein the second condition includes a condition in which a predetermined time elapses after the generation the magnetic flux energy is stopped.

9. The non-contact charger according to claim 8, wherein the controller includes a timer portion which detects elapse of the predetermined time, and

wherein the controller restarts the generation of the magnetic flux energy based on a detection of the elapse of the predetermined time by the timer portion.

10. The non-contact charger according to claim 1, wherein the controller includes a two-reference-value-comparing controller which compares the at least one of the current value and the voltage value as a detected value detected by the detecting portion with two reference values different from each other, and which controls the generation of the magnetic flux energy based on first comparison of the detected value with one of the two reference values and second comparison of the detected value with the other of the two reference values.

11. The non-contact charger according to claim 10, wherein the two reference values consist of a lower current reference value and an upper current reference value as the one and the other of the two reference values.

12. The non-contact charger according to claim 11, wherein the controller includes an oscillation-maintaining portion which controls the oscillating portion to maintain the generation of the magnetic flux energy while the detected value detected by the detecting portion after the generation of the magnetic flux energy is started is not smaller than a first current reference value as the one of the two reference values.

13. The non-contact charger according to claim 1, wherein the controller includes an erroneous-determination-preventing-type stop portion which stops the generation of the magnetic flux energy, and prevents an erroneous determination, which erroneously determines that a foreign matter is placed in the recessed portion of the casing based on the detected value when the detected value is in a transient state.

14. The non-contact charger according to claim 13, wherein the erroneous-determination-preventing-type stop portion includes a re-detecting portion which causes the detecting portion to detect again the detected value in a case where the detected value is in the transient state.

15. The non-contact charger according to claim 14, wherein the controller includes a two-reference-value-comparing controller which compares the at least one of the current value and the voltage value as a detected value detected by the detecting portion with two reference values different from each other, and which controls the generation of the magnetic flux energy based on first comparison of the detected value with one of the two reference values and second comparison of the detected value with the other of the two reference values, and

wherein the re-detecting portion determines that the detected value is in the transient state in a case where the detected value is between the two reference values, and causes the detecting portion to detect again the detected value after elapse of a waiting time that is longer than a first transitional time and a second transitional time, the first transitional time corresponding to a length of time from the placement of the cordless handset in the recessed portion of the casing until placement of the detected value from the transient state to a first steady state, the second transitional time corresponding to a length of time from removal of the cordless handset from the recessed portion of the casing until placement of the detected value from the transient state to a second steady state.

16. The non-contact charger according to claim 14, wherein the re-detecting portion includes a transitional-state detecting portion which causes the detecting portion to detect the detected value twice with a predetermined interval so as to obtain two detected values and which determines that the detected value is in the transient state in a case where a difference between the two detected values is not smaller than a predetermined difference.

17. The non-contact charger according to claim 13, wherein the erroneous-determination-preventing-type stop portion causes the detecting portion to detect the detected value twice so as to obtain two detected values with an interval that is longer than a first transitional time and a second transitional time, the first transitional time corresponding to a length of time from the placement of the cordless handset in the recessed portion of the casing until placement of the detected value from the transient state to a first steady state, the second transitional time corresponding to a length of time from removal of the cordless handset from the recessed portion of the casing until placement of the detected value from the transient state to a second steady state, and stops the generation of the magnetic flux energy in a case where both of the two detected values are between the two reference values.

18. The non-contact charger according to claim 1, wherein the detecting portion includes a circuit which detects the current value in the oscillating portion.

19. A non-contact charging system comprising:

the non-contact charger according to claim 1; and

the cordless handset which is freely attachable to and detachable from the recessed portion of the casing and which includes a secondary coil which is opposed to the primary coil upon placement of the cordless handset in the recessed portion.

20. The non-contact charging system according to claim 19, wherein the cordless handset further includes a constant current circuit which controls a current in the secondary coil such that the current is controlled to have a predetermined constant value.