Battery pack charger and tester

• US 4,147,969 A
• Filed: 10/03/1977
• Issued: 04/03/1979
• Est. Priority Date: 10/03/1977
• Status: Expired due to Term

• Current Assignee: Neuromedics Incorporated
• Original Assignee: Med General, Inc.
• Inventors: Miller, Curtis H., Arp, Robert A., Kaldun, Mark R.
• Primary Examiner(s): Hickey, Robert J.
• Application Number:
  US05/838,491
• Time in Patent Office: 547 Days
• Field of Search: 320/2-5, 320/48, 340/636
• US Class Current: 320/113
• CPC Class Codes: G01R 31/3646 for indicating electrical conditions or variables, e.g. visual or audible indicators
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: H02J 7/0049 Detection of fully charged condition
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: Y10S 320/18 Indicator or display

Abstract

A charging stand for a rechargeable battery pack having a receptacle for receiving a battery pack to be charged and/or tested and having indicator means for providing a visual indication of the condition of the battery pack. The charging stand is adapted to be connected to the output of a standard AC to DC converter and includes a circuitry for applying a charging current to the battery pack as well as sensing and indicating that charging is in progress and that the battery potential is low or fully charged. A manually operated switch is also provided to permit the testing of the condition of a battery pack. When the pack to be tested is inserted into the receptacle in the test stand and the switch is operated, a battery, which is partially discharged, will result in a "low" indication being given, but if fully charged, a "high" indication will result.

Claims

1. A charging test stand for use in recharging and testing rechargeable battery packs comprising:

(a) a receptacle having a pair of contacts therein adapted to mate with a battery pack to be charged or tested;

(b) a jack adapted to be connected to a source of direct current potential;

(c) first indicator means coupled in a series path between said jack and said pair of contacts, for providing a visual indication that charging current is flowing through said series path;

(d) a first semiconductor current control means having emitter, collector, and base electrodes, said base electrode being coupled to a first of said pair of contacts and said emitter electrode being coupled to said jack;

(e) a second semiconductor current control means having emitter, collector and base electrodes, said base electrode of said second semiconductor current control means also being coupled to said first of said pair of contacts, the emitter electrode of said second semiconductor current control means being coupled to said collector electrode of said first semiconductor current control means;

(f) second indicator means coupled between said collector electrode of said second semiconductor current control means for indicating a first state of charge of said battery packs;

(g) a third semiconductor current control means having emitter, collector and base electrodes, said base electrode of said third semiconductor current control means being coupled to said collector electrode of said second semiconductor current control means and said collector electrode of said third semiconductor current control means being coupled to said jack; and

(h) a third indicator means connected between the emitter electrodes of said second and third semiconductor current control means for indicating a second state of charge of said battery pack.

2. Apparatus as in claim 1 and further including a normally open test switch having one of its contacts connected to said jack and the other of its contacts coupled to said base electrode of said first semiconductor current control means.

3. Apparatus as in claim 1 wherein said first, second and third semiconductor current control means are PNP type transistors.

4. Apparatus as in claim 1 wherein said first, second and third indicator means are light emitting diodes.

5. Apparatus as in claim 4 wherein said light emitting diodes are mounted on said receptacle so as to be visually observable.