Battery Charger With Charge Abnormality Checking Function

• US 20110101911A1
• Filed: 10/29/2010
• Published: 05/05/2011
• Est. Priority Date: 10/29/2009
• Status: Active Grant

• Current Assignee: Hitachi KOKI Company Limited (Koki Holdings Co., Ltd.)
• Original Assignee: Hitachi KOKI Company Limited (Koki Holdings Co., Ltd.)
• Inventors: Aradachi, Takao
• Granted Patent: US 8,841,880 B2
• Time in Patent Office: Days
• US Class Current: 320/107
• CPC Class Codes: H02J 7/00036 Charger exchanging data with battery
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence

Abstract

A battery charger has an abnormal condition checking function for checking unintentional or accidental charging of a secondary battery. A charge circuit charges the battery when a switching element interposed between a power source and the battery is turned on. Current which may flow in the charge circuit is detected when the battery is not to be charged by turning the switching element on. When the current is detected in such a condition, an abnormality signal is produced to cause the charge circuit to be disabled.

Claims

1. A battery charger comprising:

a battery connecting section to which a secondary battery to be recharged is connectable;

a charge circuit configured to charge the secondary battery;

a current detecting section configured to detect current flowing in the charge circuit when charging the secondary battery has been stopped; and

a signal outputting section configured to output an abnormality signal when the current detecting section detects the current.

2. The battery charger according to claim 1, further comprising an interrupting section configured to interrupt power supply to the charge circuit based on the abnormality signal output from the signal outputting section.

3. The battery charger according to claim 1, further comprising a battery detecting section configured to detect that the secondary battery is connected to the battery connecting section,

wherein the current detecting section detects the current flowing in the charge circuit when detection made by the battery detecting section indicates that the secondary battery is not connected to the battery connecting section.

4. The battery charger according to claim 2, further comprising a battery detecting section configured to detect that the secondary battery is connected to the battery connecting section,

wherein the current detecting section detects the current flowing in the charge circuit when detection made by the battery detecting section indicates that the secondary battery is not connected to the battery connecting section.

5. The battery charger according to claim 1, further comprising:

a temperature detecting section configured to detect temperature of the secondary battery; and

a charge stop section configured to stop charging the secondary battery depending upon the temperature detected by the temperature detecting section,

wherein the current detecting section detects the current flowing in the charge circuit when the charge stop section stops charging the secondary battery.

6. The battery charger according to claim 2, further comprising:

a temperature detecting section configured to detect temperature of the secondary battery; and

a charge stop section configured to stop charging the secondary battery depending upon the temperature detected by the temperature detecting section,

wherein the current detecting section detects the current flowing in the charge circuit when the charge stop section stops charging the secondary battery.

7. A battery charger comprising:

a battery connecting section to which a secondary battery to be recharged is connectable;

a charge circuit configured to charge the secondary battery;

a charge changeover section configured to changeover a charge condition to a charge stop condition and vice versa wherein the secondary battery is charged by the charge circuit in the charge condition whereas the secondary battery is not charged in the charge stop condition;

a current detecting section configured to detect current flowing in the charge circuit when the charge condition is changed over to the charge stop condition by the charge changeover section; and

a signal outputting section configured to output an abnormality signal when the current detecting section detects the current.

8. The battery charger according to claim 7, further comprising an interrupting section configured to interrupt power supply to the charge circuit based on the abnormality signal output from the signal outputting section.

9. The battery charger according to claim 7, further comprising a battery detecting section configured to detect that the secondary battery is connected to the battery connecting section,

wherein the charge changeover section changes over the charge condition to the charge stop condition when detection made by the battery detecting section indicates that the secondary battery is not connected to the battery connecting section.

10. The battery charger according to claim 8, further comprising a battery detecting section configured to detect that the secondary battery is connected to the battery connecting section,

wherein the charge changeover section changes over the charge condition to the charge stop condition when detection made by the battery detecting section indicates that the secondary battery is not connected to the battery connecting section.

11. The battery charger according to claim 7, further comprising a temperature detecting section configured to detect temperature of the secondary battery,

wherein the charge changeover section changes over the charge condition to the charge stop condition depending upon the temperature detected by the temperature detecting section.

12. The battery charger according to claim 8, further comprising a temperature detecting section configured to detect temperature of the secondary battery,

wherein the charge changeover section changes over the charge condition to the charge stop condition depending upon the temperature detected by the temperature detecting section.

13. A battery charger comprising:

a switching power source that supplies power to a secondary battery to be recharged;

a charge on/off determining circuit that determines whether to charge the secondary battery based on qualitative information of the secondary battery;

a charge current detecting circuit that detects charge current supplied to the secondary battery for recharging;

a charge current detection controlling section configured to control the charge current detecting circuit so that detection of the charge current is to be executed or not; and

a disabling section that disables the switching power source when the charge current detecting circuit detects the charge current,

wherein when the charge on/off determining circuit determines to charge the secondary battery, the charge current detection controlling section does not allow the charge current detecting section to perform detection of the charge current whereas when the charge on/off determining circuit determines not to charge the secondary battery, the charge current detection controlling section allows the charge current detection section to perform detection of the charge current.

14. The battery charger according to claim 13, wherein the qualitative information is information about temperature of the secondary battery.

15. A battery charger comprising:

a battery connecting section to which a secondary battery to be recharged is connectable;

a charge circuit configured to charge the secondary battery;

a current detecting section configured to detect current flowing in the charge circuit;

a charge changeover section configured to changeover a charge condition to a charge stop condition and vice versa wherein the secondary battery is charged by the charge circuit in the charge condition whereas the secondary battery is not charged in the charge stop condition;

a current detection controlling section configured to allow the current detecting section to detect the current flowing in the charge circuit when the charge condition is changed over to the charge stop condition by the charge changeover section; and

a signal outputting section configured to output an abnormality signal when the current detecting section detects the current.