| 摘要 |
PURPOSE:To make knock occurrence frequency maintainable in spite of a variation in engine speed, by operating plural types of knocking occurrence rates with the operation factor varied according to the engine speed and thereby setting a timing advance correction value. CONSTITUTION:The table value stored in a memory 36c from the engine speed detected via a crank angle sensor 20 is retrieved by a central processing unit 36b at a control unit 36 whereby a reference knock occurring ignition number, a timing advance judging ignition number and a timing advance stand-by ignition number are selected. And, whether there is knocking or not is confirmed from output of a knock sensor 32, and when no knocking occurs there, the knock occurrence factor subtracting the reference knock occurring ignition number by the timing advance judging ignition number is operated. When this knock occurrence factor exceeds the specified value, timing advance correction is stopped, but when it is less than the specified value, the elapse of the timing advance stand-by ignition number is judged and this timing advance correction takes place. With this constitution, even if the engine speed is varied to some extent, knock occurrence frequency is equalizable. |
