JPS57200670A - Ignition timing controlling apparatus for internal- combustion engine - Google Patents

Abstract

PURPOSE:To accomplish fine control on the ignition timing of an internal-combustion engine, by judging the intensity of knocking from the logical product or logical sum of the outputs of a plurality of knocking detecting circuits, and determining the quantity of delay of the ignition timing according to the result of the above judgement. CONSTITUTION:Monostable multivibrators 4127, 4227 connected to respective knocking detectors are connected respectively to an AND circuit 431 and an OR circuit 432 of a circuit 43 for varying the quantity of delay of the ignition timing. Further, a voltage- current converter 434 is provided for converting the output signals of the AND circuit and a buffer circuit 433 into current. The apparatus of this invention further comprises a circuit 44 for calculating the quantity of delay of the ignition timing, which calculates the quantity of delay of the ignition timing to a standard igntion timing from knocking signals and output signals of the circuit 43 relared to the quantity of delay of the ignition timing per one knocking. Thus, since a plurality of knocking detectors are connected to the AND circuit 431 and the OR circuit 432 and the quantity of delay of the ignition timing can be determined from the output signal of these circuits, the ignition timing can be controlled finely according to the intensity of knocking.