Storage battery charging and monitoring apparatus

• US 4,571,533 A
• Filed: 01/21/1983
• Issued: 02/18/1986
• Est. Priority Date: 01/21/1983
• Status: Expired due to Fees

• Current Assignee: Ranjit Dey
• Original Assignee: Ranjit Dey
• Inventors: Dey, Ranjit
• Primary Examiner(s): HICKEY, ROBERT
• Application Number:
  US06/459,888
• Time in Patent Office: 1,124 Days
• Field of Search: 320/DIG. 2, 320/57, 320/59, 320/39, 320/40, 320/25, 320/26, 320/48
• US Class Current: 320/163
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: Y10S 320/12 Precharging analysis, e.g. determining presence of battery
• CPC Class Codes: Y10S 320/20 Polarity
• CPC Class Codes: Y10S 320/21 State of charge of battery

Abstract

A battery charging apparatus automatically charges a storage battery to a predetermined voltage level in a rate proportional to the voltage condition of the battery. The charging apparatus is operative only when the battery is properly connected to its output terminals and a suitable alternating current source is present at its input. The apparatus also has means to signal improper reverse polarities connection to the storage battery. A monitoring device is provided in association with the charging apparatus, which is operative to provide a sequential light signal to indicate the voltage condition of the battery.

Claims

1. A battery charging apparatus having a first output terminal and a second output terminal, for charging a storage battery having a positive electrode operatively connected to said first output terminal and a negative electrode operatively connected to said second output terminal, comprising

a stepdown transformer means operative to provide an alternating current of a selected level, said stepdown transformer means having a secondary winding with a centre tap connected to said first output terminal,

silicon controlled rectifier means coupled to said transformer means having an output terminal connected to said second output terminal, said rectifier means being operative selectively to provide and to terminate a direct current for charging said storage battery, control means comprising two transistor means each having base, emitter and controller electrodes wherein the emitter electrodes are commonly connected to said first output terminal, one transistor means having resistor means connected to the base electrode therein and responsive to current flowing through said resistor means to establish a reference voltage, the second transistor means having adjustable resistor means connected to the base electrode therein, said adjustable resistor means being operative to establish a selected charging voltage level, said second transistor means being responsive to comparison of said selected charging voltage level to said reference voltage to selectively activate and deactive said silicon controlled rectifier means for charging said storage battery with said direct current.

a diode means having a cathode terminal and an anode terminal, a resistor means connected to said cathode terminal of said diode means and said commonly connected emitter electrodes of said two transistor means, and said anode terminal of said diode means being connected to said first output terminal, a second resistor means connected in series to said adjustable resistor means, a switch connected in parallel to said second resistor means and operative to short circuit said second resistor means to provide a second selected voltage level for charging said storage battery,

a second diode means and a third diode means each having a cathode terminal and an anode terminal, the anode terminals of said second diode means and third diode means being commonly connected together,

said silicon controlled rectifier means having a first silicon controlled rectifier and a second silicon controlled rectifier both having an anode terminal connected commonly to said second output terminal, said first silicon controlled rectifier having a cathode terminal connected to one terminal of said secondary winding of said transformer means and a gating terminal connected to said cathode terminal of said second diode means, said second silicon controlled rectifier having a cathode terminal connected to a second terminal of said secondary winding of said transformer means, and a gating terminal connected to said cathode terminal of said third diode means, a first resistive means connected between said gating terminal of said first silicon controlled rectifier and said first terminal of said transformer means,

a second resistive means connected between said gating terminal of said second silicon controlled rectifier and said second terminal of said transformer means, a light emitting means having a cathode terminal connected to said cathode terminal of said second silicon controlled rectifier,

a third transistor means having a collector electrode, emitter electrode and a base electrode, said anode terminal of said light emitting means being connected to said collector electrode of said third transistor means, a second resistive means having one terminal connected to said emitter electrode of said third transistor means and a second terminal connected to said second output terminal, a third resistive means having one terminal connected to said base electrode of said third transistor means and a second terminal connected to said second output terminal.

2. A battery charging apparatus according to claim 1 including a fourth diode means having an cathode terminal and an anode terminal, siad cathode terminal being connected to said second output terminal, a sound signal generating means having a first input terminal and second input terminal, said anode terminal of said fourth diode means being connected to said first terminal of said sound signal generating means, a fourth resistive means connected to said second input terminal of said fourth diode means and also connected to said first output terminal, a capacitor means connected between said anode terminal of said fourth diode means and said first output terminal.

3. A battery charging apparatus according to claim 2 including a monitoring means operative to connect to said storage battery to provide sequential light indications of said instant voltage level of said battery.

4. A voltage monitoring apparatus for a storage battery, comprising first terminal means and second terminal means operative for connecting to the positive and negative electrodes respectively of said battery,

a transistor means having a base electrode, emitter electrode and collector electrode, said emitter electrode being connected to said second terminal means, said collector electrode being connected to a cathode terminal of a light emitting diode, said light emitting diode having an anode electrode connected to a series resistor and said series resistor being connected to said first terminal means, a first resistor means having one terminal and a second terminal, a second resistor means having one terminal and a second terminal, a third resistor means having one terminal and a second terminal, a fourth resistor means having one terminal and a second terminal, said one terminal of said first resistor means being connected to said emitter electrode of said transistor means, and said second terminal of said first resistor means being connected to said one terminal of said second resistor means, said second terminal of said second resistor means being connected to said base electrode of said transistor means, said one terminal of said third resistor means being connected to said base electrode of said transistor means, said second terminal of said third resistor means being connected to said one terminal of said fourth resistor means, said second terminal of said fourth resistor means being connected to said first terminal means, at least one light indication means connected between said first terminal means and second terminal means, said light indication means comprising a switching transistor means having a base electrode, emitter electrode and collector electrode wherein said emitter electrode is connected to said second terminal of said first resistor means, said base electrode is connected to a series resistor, and said series resistor being connected to said second terminal of said first resistor means, said base electrode is also connected to a second series resistor, and said second series resistor being connected in series to a zener diode means, and said zener diode means being connected to said first terminal means, a light emitting diode having a anode terminal and a cathode terminal, said collector electrode of said switching transistor means being connected to said cathode terminal of said light emitting diode and said cathode terminal of said light emitting diode and said anode terminal of said light emitting diode being connected to said one terminal of said fourth resistor means.