System to monitor fuel level in a tank, and fuel dispensed from the tank, to determine fuel leakage and theft losses

Claim 1

In apparatus to monitor liquid fuel inventory in a tank, and employing dispenser means to dispense liquid fuel from the tank, and including pulse producing means that produces electrical pulses corresponding to volumetric increments of liquid fuel dispensed, the combination comprising: a) interface means operatively connected to said pulse producing means to sense said pulses from time t o to time t n and to convert said pulses into first volume indicating data values corresponding to amount of fuel dispensed from the tank between t o and t n , b) sensor means at the tank to sense liquid level in the tank at t o and at t n and said interface means operatively connected to said sensor means, to provide second volume indicating data values corresponding to the amount of fuel leaving the tank by said dispensing and also by any theft or leakage, between t o and t n , c) and computer means operatively connected to said interface means to receive said first and second data values and to process said first and second data values for providing an output indicative of non-dispensed loss from the tank.