초록 ▼

The operation of an internal combustion engine in the region of its lean-running limit is controlled on the basis of engine roughness as measured by an inductive crankshaft transducer. Its periodic signal gates the counting in a digital down-counter, from a pre-set number, at a frequency proportiona

The operation of an internal combustion engine in the region of its lean-running limit is controlled on the basis of engine roughness as measured by an inductive crankshaft transducer. Its periodic signal gates the counting in a digital down-counter, from a pre-set number, at a frequency proportional to r.p.m. The content of the down counter is counted up or down in a subsequent up-down counter depending on the value of its own most significant bit which indicates the algebraic sign of the phase comparison between the transducer frequency and the r.p.m.-proportional frequency. Two digital integrating stages eliminate effects due to constant engine acceleration. A decoder supplies a control signal to a final control element for fuel, air or exhaust control.

대표청구항 ▼

A method for obtaining a signal for controlling the operation of an internal combustion engine, said engine including a rotating crankshaft, comprising the steps of: sensing the rotation of the crankshaft and generating a first signal representative of the irregularities of crankshaft motion; derivi

A method for obtaining a signal for controlling the operation of an internal combustion engine, said engine including a rotating crankshaft, comprising the steps of: sensing the rotation of the crankshaft and generating a first signal representative of the irregularities of crankshaft motion; deriving a pulse signal from said first signal; generating a second signal representative of a regularly rotating crankshaft; performing a phase comparison between said first signal and said second signal; generating a second pulse train of variable frequency from the twice-integrated results of said phase comparison; applying said second pulse train to the counting input of a down counter circuit; gating said down counter circuit by the first pulse train of a frequency substantially less than that of said second pulse train; supplying the contents of said down counter circuit to the jam of an up-down counter and gating said up-down counter by said first pulse train for counting at a constant system clock frequency; thereby performing said phase comparison and generating a datum whose duration is proportional to changes in the period of rotation of the crankshaft.