PURPOSE: To make it possible to prevent engine operating failure by providing a signal processing circuit for delivering false pulses as an ignition control signal when either one of first and second reference position pulses is disappeared.
CONSTITUTION: Transistors TR1, TR2 are turned of and off, respectively, by ignition control signals S14, S15 due to reference position pulses S7, S8 so that ignition plugs #1, #4 and the ignition #3, #2 are ignited, alternately. Estimating that the pulses S7 are not delivered, caused by the breaking of wire in a magnetic sensor SN1, since the ignition control signal S15 sets a flip-flap circuit 16 in this case, the output signal S18 of the flip-flap circuit 16 is at high level but the inverted signal S19 is at low level so that a counter 7 counts crank angle pulses. However, a signal S10 becomes rectangular pulses, since the counter 7 is not reset, so that a differential signal S11 during the rise time of the rectangular signal is delivered from a circuit 9, and a signal S12 is delivered from an AND circuit 10 since both signals S11, S18 are at high level, thereby the ignition control signal S14 is delivered without disappearing.
FUJII MASAHIKO
HIROZAWA YOSHIAKI
HONDA MOTOR CO LTD
| JPS591107U | 1984-01-06 | |||
| JPS5263530A | 1977-05-26 |