Fuel meter

• US 4,596,216 A
• Filed: 06/01/1982
• Issued: 06/24/1986
• Est. Priority Date: 06/01/1982
• Status: Expired due to Fees

• Current Assignee: Microfuel Technologies Incorporated
• Original Assignee: Microfuel Technologies Incorporated
• Inventors: Speed, Robert F.
• Primary Examiner(s): Miller, Carl Stuart
• Application Number:
  US06/383,462
• Time in Patent Office: 1,484 Days
• Field of Search: 123/357-359, 123/494, 73/119 A, 73/113
• US Class Current: 123/357
• CPC Class Codes: F02M 59/44 Details, components parts, or accessories not provided for in, or of interest apart from, the apparatus of groups F02M59/02 - F02M59/42; Pumps having transducers, e.g. to measure displacement of pump rack or piston
• CPC Class Codes: F02M 65/00 Testing fuel-injection apparatus, e.g. testing injection timing testing of ignition F02P17/00; measuring fuel consumption G01F9/00; Cleaning of fuel-injection apparatus
• CPC Class Codes: G01F 9/023 with electric, electro-mechanic or electronic means

Abstract

Apparatus for measuring fuel consumption in an internal combustion engine having controllable fuel injectors that meter fuel to corresponding cylinders at predetermined delivery rates under throttle control senses the amount of fuel being delivered to each cylinder by a potentiometer that generates a signal which is proportional to the linear displacement of a throttle rack gear. In one embodiment a transducer generates another signal proportional to the rotary speed of the engine and both signals are amplified at a fixed gain corresponding to the number of working engine cylinders to produce a product signal that is applied to an analog meter or a digital display circuit which indicate the rate of engine fuel consumption. Another embodiment is provided with a totalizer circuit that is responsive to the product signal relative to a predetermined time frame for indicating the total fuel consumed and both embodiments function to provide accurate readings without opening any fuel piping systems to meter and register fuel flow.

Claims

1. In an internal combustion engine having a plurality of adjustable-volume fuel injectors metering fuel to corresponding ones of engine cylinders at a unit volume rate adjustably responsive to the setting of a manual throttle control comprising a rack gear engaging a pinion gear of each injector for predetermining the volume of an injection chamber thereof, a fuel input line leading to each chamber from a fuel source, a fuel overflow line returning from each chamber to the fuel source and a fuel output line communicating each chamber with a corresponding engine cylinder, the improvement comprising, in combination:

monitor means generating an alternating current signal at a frequency related directly to the rotary speed of the engine;

signal converter means adapted to receive the alternating current signal and converting same to a direct current voltage proportional to the rotary speed of the engine;

potentiometer means mechanically linked to the rack gear for linearly tracking the lateral displacement thereof, the potentiometer means having a pair of terminals connected to the signal converter means to receive the direct current voltage as a source of operating voltage and a slider terminal at which is generated a quotient signal representing the direct current voltage divided by the lateral displacement of the rack gear which is proportional to the precise unit volume fuel charge of one injector;

multiplier means having an input connected to the slider terminal and an output generating a signal corresponding to the product of the quotient signal and a constant multiplier representing the number of working engine cylinders;

first display means coupled to the multiplier means and responsive to the output signal for displaying a precise rate of engine fuel consumption;

a calibration potentiometer having a pair of terminals connected across the output of the multiplier means;

a voltage to frequency converter having an input connected to a slider terminal of the calibration potentiometer and an output producing a high frequency alternating current signal related to the magnitude of the voltage at the slider terminal;

a binary counter adapted to receive the high frequency alternating current signal and to divide down same to a predetermined rate corresponding to the quantity of fuel consumed; and

second display means coupled to the binary counter and responsive to the divided signal for displaying the quantity of fuel consumed.

3. The improvement as claimed in claim 1 wherein the multiplier means comprises an operational amplifier having an adjustable feedback loop for setting the amplifier gain to correspond to the predetermined constant multiplier and wherein the output signal is a second direct current voltage that is proportional to the rate of fuel consumption.

4. Apparatus as claimed in claim 3 wherein the display means comprises an analog voltmeter calibrated in predetermined volume units of fuel consumed per unit time.

5. The improvement as claimed in claim 3 wherein the first display means comprises an analog to digital converter operatively connected to a digital display.

6. The improvement as claimed in claim 3 wherein the first display means comprises a microprocessor programmed to provide a visual readout, input and output ports under control of the program and a video monitor operatively connected to the output port.

2. A method for measuring fuel consumption in an internal combustion engine having a plurality of adjustable-volume fuel injectors metering fuel to corresponding ones of engine cylinders at a unit volume rate adjustably responsive to the setting of a manual throttle control comprising a rack gear engaging a pinion gear of each injector for predetermining the volume of an injection chamber thereof, a fuel input line leading to each chamber from a fuel source, a fuel overflow line returning from each chamber to the fuel source and a fuel output line communicating each chamber with a corresponding engine cylinder, comprising the steps of:

generating an alternating current signal at a frequency related directly to the rotary speed of the engine;

converting the alternating current signal to a direct current voltage proportional to the rotary speed of the engine;

linearly tracking the lateral displacement of the rack gear via potentiometer means and generating a quotient signal at a slider terminal thereof representing the direct current voltage divided by the lateral displacement of the rack gear which is proportional to the precise unit volume fuel charge of one injector;

generating a product of the quotient signal and a constant multiplier representing the number of working engine cylinders;

displaying a precise rate of engine fuel consumption coresponding to the product of the quotient signal and the constant multiplier;

converting the product of the quotient signal and the constant multiplier to a low frequency counter signal recurring at a frequency related to the magnitude of the product of the quotient signal and the constant multiplier;

counting the recurrences of the counter signal; and

displaying the counted recurrences as precise quantified units of fuel consumed.

7. A method as claimed in claim 2 wherein the step of converting the product of the quotient signal and the constant multiplier to a low frequency counter signal comprises the intermediate steps of:

converting the product of the quotient signal and the constant multiplier to a high frequency alternating current signal recurring at a frequency related to the magnitude of the product of the quotient signal and the constant multiplier; and

dividing down the high frequency alternating current signal to the low frequency counter signal.