Low battery voltage detection and warning system

• US 5,900,734 A
• Filed: 12/22/1997
• Issued: 05/04/1999
• Est. Priority Date: 12/22/1997
• Status: Expired due to Fees

• Current Assignee: Edward J Munson Jr (Edward J. Munson)
• Original Assignee: Edward J Munson Jr (Edward J. Munson)
• Inventors: Munson, Edward J
• Primary Examiner(s): Do, Diep N.
• Application Number:
  US08/995,837
• Time in Patent Office: 498 Days
• Field of Search: 324/426, 324/427, 324/429, 324/433, 324/435, 340/636, 320/134, 320/136
• US Class Current: 324/433
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: G01R 31/006 on road vehicles, e.g. automobiles or trucks testing of ignition installations peculiar to internal combustion engines F02P17/00
• CPC Class Codes: G01R 31/3647 for determining the ability of a battery to perform a critical function, e.g. cranking
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm

Abstract

A low battery voltage detection and warning system connected to sense a voltage charge of a power source within a vehicle such as the vehicle battery. The low battery voltage detection and warning system includes a voltage sensor connected to the power source for sensing a voltage value of the power source and a processing device connected to the voltage sensor for comparing the sensed voltage value to a reference value and determining if the sensed voltage value is less than the reference value. An alarm is connected to the processing device for generating an alarm upon a determination by the processing device that the sensed voltage value is less than the reference value. The alarm may produce at least one of an audible and visual alarm to alert the operator of the vehicle that the battery voltage is low and should be checked. The determination that the battery voltage is low indicates that the vehicle will only start a few more times before the battery is charged to a value too small to start the vehicle.

Claims

1. In a vehicle having an engine, ignition, and a battery for starting said vehicle, a low battery voltage detection and warning system comprising:

a) a voltage sensor connected to said battery for sensing the full voltage value of said battery;

b) a source of a fixed voltage which is the reference voltage;

c) comparator means connected to said voltage sensor and to said reference voltage source for comparing the full voltage value of said battery with said reference voltage;

d) an alarm connected to said comparator means for generating an alarm upon a determination by said comparator means that the voltage value of said battery is less than the reference voltage;

e) an ignition switch connected between said alarm and said comparator means normally open when said ignition is off wherein activation of said ignition by closing of said switch energizes said alarm when the battery voltage value is below said reference voltage; and

f) said alarm including means for indicating visually on the dashboard whether the battery voltage is above or below said reference voltage comprising a voltage regulator to regulate the amount of voltage provided by said comparator means and a green LED and a red LED connected to the output of said voltage regulator with said green LED in a forward biased direction and said red LED in a reversed bias direction so that said green LED is illuminated when said comparator means provides a signal indicative of a sensed voltage below the reference voltage and said red LED is illuminated when said comparator means provides a signal indicative of a sensed voltage above that of the reference voltage.

2. The low battery voltage detection and warning system of claim 1 in which said battery has positive and negative terminals and said voltage sensor is connected across said positive and negative terminals.

3. The low battery voltage detection and warning system of claim 2 in which an audible alarm is also generated when said battery voltage value is less than said reference voltage.