Battery recharging circuit with indicator means

• US 4,563,629 A
• Filed: 09/13/1983
• Issued: 01/07/1986
• Est. Priority Date: 09/13/1983
• Status: Expired due to Term

• Current Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Inventors: Keiper, R. Steven
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): NOT, DEFINED
• Application Number:
  US06/531,632
• Time in Patent Office: 847 Days
• Field of Search: 320/2, 320/48, 320/DIG. 1, 340/636
• US Class Current: 320/134
• CPC Class Codes: F21L 4/085 Pocket lamps
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: Y10S 320/21 State of charge of battery

Abstract

A recharging circuit including a diode and a battery serially connected and coupled in parallel to a power source includes (a) a first indicator connected across the power source and illuminated by a charging current delivered by the power source; (b) a second indicator connected between the power source and the junction of the battery and diode, and which is illuminated by discharge current delivered by the battery in the absence of charging current from the power source, and (c) a transistor coupled across the power source and to the second indicator, and being biased by charging current so as to prevent illuminated of the second indicator. The recharging circuit is included in a rechargeable flashlight and the first and second indicators are formed by a single bi-color light emitting diode.

Claims

1. A recharging circuit including a diode and a battery serially connected and coupled in parallel to a power source, comprising:

first means connected across said power source for indicating the presence of a charging current delivered by the power source;

second means connected between said power source and the junction of said diode with said battery for indicating the presence of a discharge current delivered by said battery; and

a transistor coupled across said power source and to said second indicating means, said transistor being biased on by said charging current to prevent energization of said second indicating means and being off in the absence of said current to permit energization of said second indicating means by said discharge current.

2. The battery recharging circuit of claim 1, wherein said transistor has a base, a collector and an emitter, said base and said emitter being coupled to said power source, and said collector being coupled to said second indicating means.

3. The battery recharging circuit of claim 1, wherein said transistor is coupled to said power source via a divider network comprising serially connected resistors coupled in parallel with said power source.

4. The battery recharging circuit of claim 1, wherein said first indicating means includes a serially connected light emitting diode.

5. The battery recharging circuit of claim 1, wherein said first indicating means includes a switch for selectively decoupling said first indicating means from said power source and for selectively decoupling said second indicating means from said battery.

6. The battery recharging circuit of claim 1, wherein said second indicating means includes a light emitting diode.

7. The battery recharging circuit of claim 1, further comprising a lightbulb and a switch connected in series across said battery, said lightbulb being selectively connected to said battery through said switch.

8. The battery recharging circuit of claim 1, wherein said first indicating means includes a first light emitting diode and said second indicating means includes a second light emitting diode, said first and second light emitting diodes together comprising a bi-color light emitting diode.

9. A recharging circuit with means for indicating the presence or absence of a charging current across a rechargeable battery connected in parallel with a power source, comprising:

a power charging indicating circuit with means for indicating the absence of said charging circuit;

a power failure indicating circuit with means for indicating the absence of said charging current; and

a transistor coupled to said power failure indicator circuit and said power source, said transistor being biased on in the presence of said charging current thereby do-energizing said power failure indicator circuit, and being off in the absence of said charging current, said power failure indicator circuit thereby being energized by a current from said battery.

10. The recharging circuit of claim 9, wherein said power charging indicating circuit includes a serially connected light emitting diode and a resistor with the cathode of said diode being coupled to the power source, the anode of said diode being coupled to one end of said resistor and the other end of said resistor being coupled to the power source.

11. The recharging circuit of claim 9, wherein said power failure indicating circuit includes a serially connected light emitting diode and a resistor, all being coupled in parallel across said rechargeable battery, said light emitting diode having an anode and a cathode, and said battery having one positive and one negative terminal with the positive battery terminal being connected to one end of said resistor and the other end of said resistor being coupled to the anode of said light emitting diode, the cathode of said diode being connected to the negative terminal of said battery, such that battery current is provided to said diode.

12. The recharging circuit of claim 9, wherein said transistor has a base, a collector and an emitter, said base and said emitter being coupled to the power source, and said collector being coupled to said power failure indicating circuit.

13. The recharging circuit of claim 9, further comprising a diode connected in series between said power source and said rechargeable battery, said diode being back biased in the presence of a battery voltage, thereby ensuring that the battery current does not flow to the power source.

14. The recharging circuit of claim 9, further comprising a voltage divider network coupled across said power source, said voltage divider including two serially coupled resistors, and said transistor being coupled to said power source via said voltage divider network, whereby said voltage divider network provides a biasing voltage for turning on said transistor in the presence of a charging current from said power source.