ELECTRONIC FUEL CONSUMPTION METER

• US 3,812,710 A
• Filed: 07/07/1971
• Issued: 05/28/1974
• Est. Priority Date: 07/09/1970
• Status: Expired due to Term

• Current Assignee: Gunther Bauman, Hermann Eisele, Josef Wahl, Peter Schmidt
• Original Assignee: Gunther Bauman, Hermann Eisele, Josef Wahl, Peter Schmidt
• Inventors: Bauman, Gunther, Schmidt, Peter, Eisele, Hermann, Wahl, Josef
• Primary Examiner(s): Queisser, Richard C.
• Assistant Examiner(s): Kreitman, Stephen A.
• Application Number:
  US05/160,302
• Time in Patent Office: 1,056 Days
• Field of Search: 73/113-117,206 307/273
• US Class Current: 73/114.52
• CPC Class Codes: F02D 2200/0406 Intake manifold pressure
• CPC Class Codes: F02D 41/3005 Details not otherwise provided for
• CPC Class Codes: F02D 41/407 of the in-line type
• CPC Class Codes: G01F 9/001 with electric, electro-mechanic or electronic means G01F9/008 and G01F9/02 take precedence
• CPC Class Codes: G08C 15/00 Arrangements characterised by the use of multiplexing for the transmission of a plurality of signals over a common path

Abstract

Electric signals, corresponding to two or more engine operating parameters, such as rotational speed of the engine drive shaft and the setting of the throttle valve or a rotational speed and the pressure in the intake manifold or the pressure in the intake manifold and the setting of the throttle valve, are obtained by transducers, these signals being fed to an evaluating circuit that produces an electric output that is conducted to a meter that reads fuel consumption in unit distance, or unit time, travelled.

Claims

1. An arrangement for continuously measuring and indicating the instantaneous fuel consumption of an internal combustion engine, comprising, in combination, transducer means for converting at least two engine operating parameters related to fuel consumption into corresponding electric signals;

an evaluating circuit connected to said transducer means to receive as input said corresponding electric signals for providing an electric output signal indicative of fuel consumption;

meter means connected to receive as input said output signal for visually showing the fuel consumption of the engine, wherein said evaluating circuit includes a constant frequency oscillator, a gate connected to receive as input the output of said oscillator, a circuit having an output for providing pulses of which the lengths correspond to the time that fuel is supplied to the engine, the output of said correction circuit being connected to said gate to control the operation of the latter so that the number of oscillator pulses passed by said gate corresponds to said time, a first counter connected to the output of said gate, said first counter having a reset input, a store connected to receive as input the output of said first counter, said store including a control input, said meter means being connected to the output of said store, to provide a visual indication of the fuel consumption rate, a pulse generator for providing pulses at a frequency proportional to engine speed, a second counter connected to receive as input the output of said pulse generator for providing a reset output pulse after a predetermined number of pulses has been received from said pulse generator, said second counter having a reset input, the output of said second counter being connected to said control input of said store.

2. An arrangement as defined in claim 1, and further including a digital to analog converter connected to receive as input the output of said store, and wherein said meter means is connected to the output of said store through the intermediary of said converter so that said meter means provides an analog indication of the fuel consumption rate.

3. An arrangement as defined in claim 1, and further including a time delay circuit connected between the output of said second counter and the reset inputs of the first and second counters, so that a reset output pulse from said second counter resets both said first and second counters after a delay period determined by said time delay circuit.

4. An arrangement for continuously measuring and indicating the instantaneous fuel consumption of an internal combustion engine, comprising, in combination, transducer means for converting at least two engine operating parameters related to fuel consumption into corresponding electric signals;

an evaluating circuit connected to said transducer means to receive as input said corresponding electric signals for providing an electric output signal indicative of fuel consumption; and

meter means connected to receive as input said output signal for visually showing the fuel consumption of the engine, wherein said evaluating circuit includes a pulse generator for generating pulses of which at least two characteristics are varied in dependence upon said corresponding electrical signals, wherein said pulse generator is a monostable multivibrator, said evaluating circuit further including means for triggering said monostable multivibrator to the unstable state in synchronism with the rotation of the engine drive shaft, and further wherein said transducer means controls the width of said pulses.

5. The arrangement as defined in claim 4, including electronic fuel injection control means, said control means at least in part comprising said evaluating circuit.

6. The arrangement as defined in claim 5, wherein said monostable multivibrator is specific to said evaluating circuit.

7. The arrangement as defined in claim 5, as used in a motor vehicle, wherein said meter means has a plurality of scales, One for each constant transmission ratio of the engine, for showing the fuel consumption per unit distance travelled.

8. The arrangement as defined in claim 5, as used in a motor vehicle, wherein said meter means has a single scale, and wherein said evaluating circuit includes means for switching for each gear so as to show on said single scale the fuel consumption in each gear.

9. The arrangement as defined in claim 7, wherein one engine operating parameter is the rotational speed of the drive shaft.

10. The arrangement as defined in claim 7, wherein one engine operating parameter is the rotational speed of the driven wheels.

11. The arrangement as defined in claim 8, wherein one engine operating parameter is the rotational speed of the drive shaft.

12. The arrangement as defined in claim 8, wherein one engine operating parameter is the rotational speed of the driven wheels.

13. The arrangement as defined in claim 9, further including a fuel injection pump, said fuel injection pump having a control rod for varying, in dependence on the position thereof, the amount of fuel injected, and wherein one engine operating parameter is the position of said control rod.

14. The arrangement as defined in claim 10, further including a fuel injection pump, said fuel injection pump having a control rod for varying, in dependence on the position thereof, the amount of fuel injected, and wherein one engine operating parameter is the position of said control rod.

15. The arrangement as defined in claim 11, further including a fuel injection pump, said fuel injection pump having a control rod for varying, in dependence on the position thereof, the amount of fuel injected, and wherein one engine operating parameter is the position of said control rod.

16. The arrangement as defined in claim 12, further including a fuel injection pump, said fuel injection pump having a control rod for varying, in dependence on the position thereof, the amount of fuel injected, and wherein one engine operating parameter is the position of said control rod.

17. An arrangement for continuously measuring and indicating the instantaneous fuel consumption of an internal combustion engine, as used in a motor vehicle, comprising, in combination, transducer means for converting at least two engine operating parameters related to fuel consumption into corresponding electric signals;

and evaluating circuit connected to said transducer means to receive as input said corresponding electric signals for providing an electric output signal indicative of fuel consumption; and

meter means connected to receive as input said output signal for visually showing the fuel consumption of the engine, wherein said evaluating circuit includes a pulse generator for generating pulses of which at least two characteristics are varied in dependence upon said corresponding electrical signals, wherein said pulse generator is a monostable multivibrator, said evaluating circuit further including means for triggering said monostable multivibrator to the unstable state in synchronism with the rotation of the engine drive shaft, and further wherein said transducer means controls the width of said pulses, further including electronic fuel injection control means and electromagnetic fuel injection spray valves, said electronic fuel injection control means including a monostable multivibrator for controlling in dependence on said engine operating parameters the opening times of said electromagnetic fuel injection spray valves, and wherein said monostable multivibrator is also said pulse generator of said evaluating circuit, further including a correction circuit connected to receive as input the pulse output of said monostable multivibrator for providing, as output, pulses shortened, with respect to the multivibrator pulse output, an amount corresponding to the reaction times of said electromagnetic fuel injection spray valves.

18. The arrangement as defined in claim 17, further including an invertiNg stage connected to the output of said monostable multivibrator, and wherein said correction circuit includes a normally conductive delay transistor connected to receive as input the pulse output of said inverting stage, a charging circuit connected in the base current path of said delay transistor for cutting off the latter an amount of time equal to the reaction time of the fuel injection spray valves, a normally conductive summing transistor connected to receive as input the output of said inverting stage and of said delay transistor for being non-conductive when said delay transistor is conductive while an output pulse is present from said inverting stage, and an output transistor connected to receive as input the output of said summing transistor for being conductive when the latter is non-conductive.

19. The arrangement as defined in claim 17, further including circuit means for providing a voltage that is proportional to the time per unit distance travelled.

20. The arrangement as defined in claim 19, further including means for generating reference pulses related to the speed of the vehicle, and wherein said circuit means includes a saw-tooth generator connected to receive as input said reference pulses, said saw-tooth generator generating a saw-tooth pulse for each reference pulse, said saw-tooth pulse having a peak value that is directly proportional to the time per unit distance travelled, said circuit means further including a peak voltage rectifier connected to receive as input the saw-tooth pulses for changing the peak voltages of the latter into a direct current voltage that is proportional to the time per unit distance travelled, said direct current voltage being the output voltage of said circuit means.

21. The arrangement as defined in claim 20, wherein said saw-tooth generator includes a constant current source and a capacitor, said capacitor being connected to said constant current source to be charged by the latter.

22. The arrangement as defined in claim 20, wherein said meter means is connected to the output of said circuit means and to the output of said correction circuit to be connected by the latter to the polarity necessary to complete a circuit through said meter means and for a time that is directly proportional to the length of time that fuel is injected during each injection.

23. In a vehicle, in combination with an internal combustion engine provided with an electromagnetic fuel injection valve for injecting fuel into an engine cylinder, an arrangement for determining and indicating the rate of fuel consumption per predetermined number of engine revolutions comprising, in combination, signal generating means for generating a first signal indicative of the rate of fuel consumption, said signal generating means comprising electronic fuel injection control means including a monostable multivibrator connected to said electromagnetic fuel injection valve and operative for controlling the opening and closing of the latter in dependence upon predetermined engine operating conditions by applying to said electromagnetic fuel injection valve a train of valve-opening pulses of variable pulse duration for opening said valve for time durations corresponding to the time durations of said valve-opening pulses, said train of valve-opening pulses constituting said first signal, and said signal generating means further including means for generating a second signal indicative of the number of rotations of said engine per unit time;

and signal processing means connected to said signal generating means and operative for receiving said first and second signals and generating an output signal indicative of the rate of fuel consumption per predetermined number of engine revolutions, said signal processing means including integrating means, and said signal processing means comprising means for applying to said integrating means a train of pulses corresponding in pulse duration to said train of valve-opening pulses, said integrating means compRising means for integrating said train of pulses corresponding in pulse duration to said train of valve-opening pulses to develop an electrical output signal dependent upon the sum of the time durations of successive openings of said fuel injection valve, to thereby develop an electrical signal dependent upon the total quantity of fuel injected by said fuel injection valve during such plurality of successive openings of said fuel injection valve.

24. A combination as defined in claim 23, wherein said integrating means comprises means operative for generating a signal proportional to the time integral of the product of said first and second signals.