BATTERY CONDITION INDICATOR

• US 3,832,629 A
• Filed: 01/26/1973
• Issued: 08/27/1974
• Est. Priority Date: 01/26/1973
• Status: Expired due to Term

• Current Assignee: Edward Cernek Jr
• Original Assignee: Edward Cernek Jr
• Inventors: Cernek, Edward Jr.
• Primary Examiner(s): Smith, Alfred E.
• Assistant Examiner(s): Hille, Rolf
• Application Number:
  US05/326,894
• Time in Patent Office: 578 Days
• Field of Search: 324/29.5 340/248B,248C,248D,249 320/48
• US Class Current: 324/436
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36

Abstract

A Battery Voltage Indicator is provided for indicating the condition of the battery or dry cells or the like by providing light flashes or a steady light from a light emitting diode when the battery voltage is in the range for a usable battery. A multi-vibrator is connected to derive its operating voltage from the battery being tested and produces an output wave that fluctuates above and below a given fraction of the multi-vibrator battery voltage but having upper and lower levels each dependent upon the battery voltage. A circuit for the light emitting diode is provided which is energized when the voltage input is above the predetermined level. Consequently the diode either emits light continuously, flashes, or remains dark, depending upon whether the battery is good, weak, or dead.

Claims

1. A Battery Condition Indicator comprising in combination:

a pair of input terminals for connection to a battery, the condition of which is to be tested;

an oscillator having an input connected to said terminals and having as a voltage output an oscillation wave that is DC biased by the voltage of said battery connected to said input;

an indicator circuit including a switch having a voltage responsive control element and means coupling said control element to the output of said oscillator, whereby the response of the indicator is dependent upon the voltage attained by the oscillator output.

2. A Battery Condition Indicator as described in claim 1 wherein the oscillator is an astable multi-vibrator with:

a load circuit; and

coupling means between a point in said load circuit and said switch control element.

3. A Battery Condition Indicator as described in claim 2 wherein the switch is a transistor with a relatively low saturation voltage and the coupling between the switch control element and the multi-vibrator circuit includes means for depressing the voltage applied to the control element.

4. A Battery Voltage Indicator as described in claim 2 in which the load circuit coupling to the switch control element comprises a Zener diode.

5. A Battery Condition Indicator as described in claim 1 wherein the switch comprises a transistor with a base, collector and emitter with a base-current discharge resistor connected between the base and the emitter, with a Zener diode coupling the base to the oscillator output.

6. A Battery Condition Indicator as described in claim 1 wherein the switch is responsive to a predetermined minimum voltage and a lamp is included in the indicator circuit whereby the battery condition is indicated by steady illumination from said lamp, flashing light, or the lamp remaining dark dependent upon the upper and lower voltage level output of the oscillator in relation to the voltage at which the switch becomes responsive.

7. A Battery Condition Indicator as described in claim 6 wherein the lamp is a light emitting diode connected in series with the switch to said input terminals.

8. A Battery Condition Indicator, comprising:

a pair of inpUt terminals for connection to a battery, the condition of which is to be tested;

a voltage responsive circuit connected to said input terminals for producing an oscillation wave that is DC biased by the voltage of said battery, the maximum and minimum voltages of said oscillation wave having a voltage level which is proportional to the voltage difference between said input terminals; and

an indicator circuit including a switch which is actuated by a predetermined voltage level, said switch coupled to said oscillation wave, said indicator producing a signal whenever said oscillation wave voltage exceeds said predetermined voltage level.