US 4,052,663 A · Timing system for measuring angle of advance of fuel injection

Abstract

A fuel injected engine timing instrument measures timing advance of fuel injection onset as referenced to a predetermined cylinder top-dead-center to provide an analog output signal proportional to fuel injection advance for the engine. This output signal is obtained by measuring the time required for an engine flywheel to move a predetermined distance which movement is sensed by a transducer responsive to timing indicia on the flywheel. An output signal from the transducer is applied to a gating circuit in combination with a signal derived from a transducer detecting the onset of fuel injection into the reference cylinder of the engine. The gating circuit is enabled by these two signals to control the duration of application of output signals from a fixed frequency oscillator to a counter. The output signal from the transducer sensing the movement of a flywheel is also used to control a second gating circuit arranged to apply the output signals from the oscillator to a second counter. The count signals from the first and second counters are compared by a ratio computing circuit to produce an analog output signal representative of the timing advance in degrees of the fuel injection onset before top-dead-center.

Claims10

Dependent claims

A fuel injection timing instrument for a fuel injected engine comprising

first means for producing a first timing signal corresponding to the occurrence of fuel injection into an engine reference cylinder,
second means for producing a second and a third timing pulse corresponding to the movement of a flywheel on the engine through a predetermined number of degrees between a first position and a second position, respectively, with said third pulse representing top-dead-center of the reference cylinder,
third means for producing a succession of fixed time division signals,
fourth means responsive to said second means and said third means for producing a first output signal having a characteristic representative of the time between the occurrence of said second and said third pulses representing the predetermined movement of the flywheel,
fifth means responsive to said first, second and third means for producing a second output signal having a characteristic representative of the time between the occurrence of the onset of the fuel injection into the engine reference cylinder and said second timing pulse, and
computing means for multiplying the ratio of said first and second output signals by a signal representative of the number of degrees on the flywheel between said first and second timing pulses to produce an output signal representative of a timing advance of the fuel injection onset before top-dead-center of the reference cylinder.

3 more elements

Dependencies are inferred from the claim text.

Timing system for measuring angle of advance of fuel injection

Life of this patent

Timing system for measuring angle of advance of fuel injection

Life of this patent

Abstract

Claims10