Battery status indicator

• US 5,099,210 A
• Filed: 06/01/1990
• Issued: 03/24/1992
• Est. Priority Date: 06/01/1990
• Status: Expired due to Fees

• Current Assignee: Koss Corporation
• Original Assignee: Koss Corporation
• Inventors: Blandino, Tom, Fortney, Neil K.
• Primary Examiner(s): Wieder, Kenneth A.
• Application Number:
  US07/531,948
• Time in Patent Office: 662 Days
• Field of Search: 324/433, 324/436, 324/426, 324/427, 324/435, 324/133
• US Class Current: 324/433
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: G01R 31/3646 for indicating electrical conditions or variables, e.g. visual or audible indicators

Abstract

A circuit for monitoring and indicating the outut level of an energy source, such as the voltage level of a battery. The circuit includes a triangle wave generator, and a comparison circuit for comparing the triangle wave form to the battery output level and generating a comparison signal. A dual color LED set displays the comparison signal. The diode set is activated in one color when the battery signal is greater than the triangle wave form, while the other color diode is activated when the battery signal is less than the triangle wave form. When the frequency of the triangular wave is two Hertz, the LED set produces discernable flashes between the first color LED and the second color LED when the battery signal is within the peak-to-peak value. The ratio of the times the LEDs are activated is a linear representation of the battery voltage between predetermined "warning" and "discharge" voltages. When the frequency of the triangular wave is thirty Hertz or greater, any flashes produced by the diode set switching between activated LEDs are not discernable by the human eye, resulting in a mixing of colors when the battery signal is within the peak-to-peak value of the triangle wave form.

Claims

1. Means for monitoring and indicating the output level of an energy source, comprising:

means for generating a signal having a triangle wave form having a predetermined peak-to-peak value;

means for comparing said triangle wave form signal to a signal related to said output level of said energy source and generating a comparison signal therefrom; and

two-state indicating means for receiving said comparison signal, and being in a first state when said comparison signal indicates that said signal related to the output level of said energy source is greater than said triangle wave form and being in a second state when said comparison signal indicates that said signal related to the output level of said energy source is less than said triangle wave form, resulting in a substantially linear representation of the output level of said energy source caused by said indicating means continually changing state, in a linear manner generally proportional to the proximity of the output level to the upper or lower peaks of said triangle wave form, while said output level is within said peak-to-peak value.

2. Monitoring means as recited in claim 1 wherein said triangle wave form has a frequency of two Hertz or less, such that said two-state indicating means produces discernable flashes between states when the output level of said energy source is within said peak-to-peak value.

3. Monitoring means as recited in claim 1 wherein said triangle wave form has a frequency of thirty Hertz or greater, such that any flashes produced by said two-state indicating means switching between states is not normally discernable.

4. A circuit for monitoring the voltage level of a battery comprising:

a wave form generating circuit for generating a voltage having a triangular wave form having a predetermined peak-to-peak value;

a comparator circuit for comparing a signal related to the battery voltage with said triangular wave form voltage; and

a dual color light emitting diode set, wherein a LED of a first color is activated when said signal related to the battery voltage is greater than said triangular wave form voltage, and wherein a LED of a second color is activated when said signal related to the battery voltage is less than said triangular wave from voltage, resulting in a substantially linear representation of said battery voltage level caused by said light emitting diodes continually being activated alternatively, in a substantially linear manner generally proportional to the proximity of the battery voltage to the upper or lower peaks of said triangle wave form, while said battery voltage level is within said peak-to-peak value of said triangular wave form.

5. A circuit as recited in claim 4 wherein said battery has a predetermined voltage at which it is substantially discharged, and when said battery voltage reaches said substantially discharged voltage, said LED of said second color is substantially continuously activated.

6. A circuit as recited in claim 4 wherein said triangular wave form has a frequency of two Hertz or less, such that said LED set produces discernable flashes between said first color LED and said second color LED when said battery voltage is within said peak-to-peak value.

7. A circuit as recited in claim 4 wherein said triangular wave form has a frequency of thirty Hertz or greater, such that any flashes produced by said LED set switching between activated LEDs is not normally discernable, resulting in a mixing of colors when said battery voltage is within said peak-to-peak value of said triangular wave form.

8. Means for monitoring and indicating the output level of an energy source, comprising:

means for generating a signal having a triangle wave form having a predetermined peak-to-peak value;

means for comparing said triangle wave form signal to a signal related to but attenuated from said output level of said energy source and generating a comparison signal therefrom; and

two-state indicating means for receiving said comparison signal, and being in a first state when said attenuated signal is greater than said triangle wave form and being in a second state when said attenuated signal is less than said triangle wave form, resulting in a substantially linear representation of the output level of said energy source caused by said indicating means continually changing state, in a linear manner, generally proportional to the proximity of the attenuated signal to the upper or lower peaks of said triangle wave form, while said attenuated signal is within said peak-to-peak value.