Apparatus for the measurement of vehicle fuel consumption

Claim 1

Vehicle fuel consumption rate measurement apparatus comprising control circuitry, an odometer linkage unit, electrically connected to the control circuitry, a fuel flow sensor unit electrically connected to the control circuitry, and a numeric display electrically connected to the control circuitry wherein (a) the odometer linkage unit includes means for producing an electrical pulse train, in which the number of pulses is related to the distance traveled by the vehicle, to drive a counter in the control circuitry; (b) the fuel sensor unit includes a fuel input port and a fuel output port with an upper fuel path and a lower fuel path therebetween, the upper fuel path including an electrically actuated valve which is adapted for being switched by the control circuitry to an open position and a closed position, and the lower fuel path including an input column and an output column extending downward of the upper fuel path on either side of the valve, the output column including a lower electrical contact, a center electrical contact and an upper electrical contact, the lower fuel path containing a body of electrolyte, which electrolyte is denser than the fuel and not miscible with the fuel, which said electrolyte is included in sufficient quantity to fill the input and output columns to a level between the lower contact and the center contact; (c) the numeric display is adapted for being activated by the control circuitry to indicate fuel consumption; and (d) the control circuitry includes a valve actuator, electrically connected to the upper contact and the lower contact, for opening the valve during a preselected recovery and readout time interval, which is initiated when the electrolyte bridges between the upper contact and the lower contact, a counter, a counter control electrically connected to the center contact and the lower contact and to the valve actuator by an actuator link and to the counter, which counter control includes means for resetting the counter to zero and enabling the counter to respond to the electrical signal from the odometer linkage unit when the electrolye bridges between the center contact and the lower contact, which counter control also includes means for disabling the counter from further response at the start of the recovery and readout time interval upon receiving a signal from the actuator link; in which said apparatus the number of pulses per unit distance travelled and the volume of the output column between the center electrical contact and the upper electrical contact are selected such that the count registered in the counter and displayed on the display is a direct reading of the fuel consumption rate.