| 摘要 |
PURPOSE:To perform a lag advance at high speed rotation and make an engine preventable from seizure or binding as well as to make an output characteristic rationalizable according to an engine speed, by varying the reference voltage to be compared with charging voltage with a lag advance circuit. CONSTITUTION:With each pulse out of pulsers 11 and 12, waveform shaping circuits 15 and 17 output a set signal SS and a reset signal RR. Charging voltage Vc of a first integrator 50 is amplified by a nonlinear circuit 80, and in time of low speed, or not reached to charging voltage Vc2 of a second integrator 55, a comparator 90 does not output any more so that ignition takes place with the RR signal. When an engine speed goes up, the Vc2 comes down whereby the comparator 90 outputs a logical signal 1 earlier than the RR signal, making it perform the timing advance. When the engine speed goes up further, the charging voltage Vc2 comes more down, and thereby a timing advance degree is made rather into a lag advance but when exceeding this speed range, the charging voltage Vc2 and a first stage tilting part of the output voltage of the circuit 80 is intersected, therefore the timing advance is stopped and thus kept in constant. |
