Rechargeable flashlight combined with a constant current battery charging circuit

• US 4,398,139 A
• Filed: 02/23/1981
• Issued: 08/09/1983
• Est. Priority Date: 11/30/1978
• Status: Expired due to Fees

• Current Assignee: Onno M. Prinsze
• Original Assignee: Onno M. Prinsze
• Inventors: Prinsze, Onno M.
• Primary Examiner(s): BEHA JR, WILLIAM
• Application Number:
  US06/236,971
• Time in Patent Office: 897 Days
• Field of Search: 320/2, 320/3, 320/10, 320/17, 320/39, 320/48, 362/183, 323/273
• US Class Current: 320/114
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits

Abstract

Apparatus for charging rechargeable batteries includes a constant current regulator connected in combination with a current limiting resistor to provide constant current for charging the rechargeable battery and a pair of light emitting diodes are used to indicate the charging status of the rechargeable battery.

Claims

1. Flashlight charging apparatus, comprising, in combination:

a rechargeable flashlight, including

a rechargeable battery comprising one or more cells,

a lamp,

a switch, having a closed position for connecting the rechargeable battery and the lamp, and having an open position for disconnecting the battery and the lamp, and

first terminal means for connecting the rechargeable flashlight to a battery charging circuit;

battery charging circuit means, including

a voltage source for charging the rechargeable battery in the rechargeable flashlight when the switch is in the closed position,

current means for providing substantially constant current for recharging the rechargeable battery without regard to the number of cells in the battery, including

voltage means connected to the voltage source, and

a first resistor combined with the voltage means for providing the substantially constant current to the rechargeable battery,

a second resistor and a diode connected in series, and

a third resistor;

a first light emitting diode connected in series with the third resistor of the current means to provide a visual indication that the rechargeable battery is being charged from the voltage source and the current means, said third resistor and first light-emitting diode being in parallel with the second resistor and diode for providing a higher substantially constant current for recharging the rechargeable battery than may flow through the first light-emitting diode; and

a second light emitting diode connected to the rechargeable battery to provide visual indication that the rechargeable battery is not being charged from the voltage source and the current means.