Control device for ignition timing of internal combustion engine

Abstract

Abstract PURPOSE:To prevent fuel consumption from getting worse by stopping a feed-back control by a low-load detecting signal of an engine during the time when a feed-back control of ignition timing is carried out on the basis of a crank angle for the maximum inner cylinder pressure. CONSTITUTION:A control circuit 10 detectes a crank angle for the maximum inner cylinder pressure by cylinder pressure sensors 1-4 and a crank angle sensor 7, and carries out the feed-back control of the ignition timing in such a manner that when the air intake rate from a air-flow meter 8 is larger than a predetermined value and if a defference between the detected crank angle for the maximum cylinder inner pressure and the predetermined target value is possitive, the basic ignition timing is advanced by a predetermined value it the difference is negative, it is retarded by a predetermined value. When the air intake rate is smaller than the predetermined value, the engine is judged in a low load condition, and if the corrective value to the basic ignition timing is positive, a predetermined value is subtracted from the corrective value, and if it is negative, a predetermined value is added so as to force the corrective value approach '0' so that the erroneous correction can be avoided by controlling the ignition timing at the value near the basic ignition timing, thus preventing fuel consumption from worsening.

Inventors

• 👤 Mamoru Shinshi
• 👤 進士　守

Bibliographic Details