Charging circuit and battery charger

• US 6,794,851 B2
• Filed: 10/28/2002
• Issued: 09/21/2004
• Est. Priority Date: 02/28/2002
• Status: Expired due to Fees

• Current Assignee: Mitsumi Electric Co., Ltd. (MinebeaMitsumi Inc.)
• Original Assignee: Mitsumi Electric Co., Ltd. (MinebeaMitsumi Inc.)
• Inventors: Murakami, Kouji, Hamai, Hidetoshi
• Primary Examiner(s): TIBBITS, PIA FLORENCE
• Application Number:
  US10/281,832
• Publication Number:
  US 20030160592A1
• Time in Patent Office: 694 Days
• Field of Search: 320/119, 320/116, 320/124, 320/125, 320/126, 320/160, 320/162, 320/163, 307/64, 307/66, 307/56
• US Class Current: 320/119
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0045 concerning the insertion or the connection of the batteries
• CPC Class Codes: H02J 7/00712 the cycle being controlled or terminated in response to electric parameters
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

A charging circuit charging predetermined first and second batteries includes: a circuit configuration by which a second charging current charging the second battery is obtained by subtracting a first charging current charging the first battery from a current supplied by a power source; and a current setting part that sets the second charging current smaller than the first charging current at least at the beginning of charging.

Claims

1. A charging circuit for charging at least a first battery either individually or together with a second battery from current supplied by a power source, the charging circuit comprising:

a circuit configuration providing a first charging current for charging the first battery and a second charging current for charging the second battery, wherein the second charging current is substantially a difference of the first charging current and the current supplied by the power source; and

a current setting part for maintaining the amount of the second charging current to be less than the amount of the first charging current for at least an initial portion of time of charging one or more batteries, wherein the current setting part comprises a diode inserted in a charging path of the second battery for decreasing a charging voltage of the second battery.

2. The charging circuit as claimed in claim 1, further comprising:

a voltage comparing part that compares the charging voltage of the second battery and a supply voltage of the power source; and

a charging current preventing part that prevents the flow of the second charging current when the supply voltage is less than the charging voltage of the second battery.

3. A charging circuit for charging at least a first battery either individually or together with a second battery from current supplied by a power source, the charging circuit comprising:

a circuit configuration providing a first charging current for charging the first battery and a second charging current for charging the second battery, wherein the second charging current is substantially a difference of the first charging current and the current supplied by the power source; and

a current setting part for maintaining the amount of the second charging current to be less than the amount of the first charging current for at least an initial portion of time of charging one or more batteries, wherein the current setting part comprises a resistor inserted in a charging path of the second battery for decreasing a charging voltage of the second battery.

4. The charging circuit as claimed in claim 3, further comprising:

a voltage comparing part that compares the charging voltage of the second battery and a supply voltage of the power source; and

a charging current preventing part that prevents the flow of the second charging current when the supply voltage is less than the charging voltage of the second battery.

5. A battery charger for charging at least a first battery either individually or together with a second battery from current supplied by a power source, the battery charger comprising:

a housing containing a charging circuit therein and having a first holding part and a second holding part, wherein the first holding part is configured to hold a mobile set in which to insert the first battery and the second holding part is configured to hold the second battery, and wherein said charging circuit comprises;

a circuit configuration providing a first charging current for charging the first battery and a second charging current for charging the second battery, wherein the second charging current is substantially a difference of the first charging current and the current supplied by the power source; and

a current setting part for maintaining the amount of the second charging current to be less than the amount of the first charging current for at least an initial portion of time of charging one or more batteries, wherein the current setting part comprises a diode inserted in a charging path of the second battery for decreasing a charging voltage of the second battery.

6. The battery charger as claimed in claim 5, further comprising:

a voltage comparing part that compares the charging voltage of the second battery and a supply voltage of the power source; and

a charging current preventing part that prevents the flow of the second charging current when the supply voltage is less than the charging voltage of the second battery.

7. A battery charger for charging at least a first battery either individually or together with a second battery from current supplied by a power source, the battery charger comprising:

a housing containing a charging circuit therein and having a first holding part and a second holding part, wherein the first holding part is configured to hold a mobile set in which to insert the first battery and the second holding part is configured to hold the second battery, and wherein said charging circuit comprises;

a circuit configuration providing a first charging current for charging the first battery and a second charging current for charging the second battery, wherein the second charging current is substantially a difference of the first charging current and the current supplied by the power source; and

a current setting part for maintaining the amount of the second charging current to be less than the amount of the first charging current for at least an initial portion of time of charging one or more batteries, wherein the current setting part comprises a resistor inserted in a charging path of the second battery for decreasing a charging voltage of the second battery.

8. The battery charger as claimed in claim 7, further comprising:

a voltage comparing part that compares the charging voltage of the second battery and a supply voltage of the power source; and

a charging current preventing part that prevents the flow of the second charging current when the supply voltage is less than the charging voltage of the second battery.

9. A battery charger for charging at least a first battery either individually or together with a second battery from current supplied by a power source, the battery charger comprising:

a housing containing a charging circuit therein and having a first holding part and a second holding part, wherein the first holding part is configured to hold the first battery and the second holding part is configured to hold the second battery, and wherein said charging circuit comprises;

a circuit configuration providing a first charging current for charging the first battery and a second charging current for charging the second battery, wherein the second charging current is substantially a difference of the first charging current and the current supplied by the power source; and

a current setting part for maintaining the amount of the second charging current to be less than the amount of the first charging current for at least an initial portion of time of charging one or more batteries, wherein the current setting part comprises a diode inserted in a charging path of the second battery for decreasing a charging voltage of the second battery.

10. The battery charger as claimed in claim 9, further comprising:

a voltage comparing part that compares a the charging voltage of the second battery and a supply voltage of the power source; and

a charging current preventing part that prevents the flow of the second charging current when the supply voltage is less than the charging voltage of the second battery.

11. A battery charger for charging at least a first battery either individually or together with a second battery from current supplied by a power source, the battery charger comprising:

a housing containing a charging circuit therein and having a first holding part and a second holding part, wherein the first holding part is configured to hold the first battery and the second holding part is configured to hold the second battery, and wherein said charging circuit comprises;

a circuit configuration providing a first charging current for charging the first battery and a second charging current for charging the second battery, wherein the second charging current is substantially a difference of the first charging current and the current supplied by the power source; and

a current setting part for maintaining the amount of the second charging current to be less than the amount of the first charging current for at least an initial portion of time of charging one or more batteries, wherein the current setting part comprises a resistor inserted in a charging path of the second battery for decreasing a charging voltage of the second battery.

12. The battery charger as claimed in claim 11, further comprising:

a voltage comparing part that compares the charging voltage of the second battery and a supply voltage of the power source; and

a charging current preventing part that prevents the flow of the second charging current when the supply voltage is less than the charging voltage of the second battery.