Crank angle detecting apparatus for an internal combustion engine.

摘要

There is disclosed a crank angle sensor 1, 11 which creates a reference position signal (G1, G2) and a crank angle signal (C1 to C12) as an internal combustion engine rotates. A counter means (2, 12) counts the crank angle signals and, when its count value has reached a first set value, it goes to a second set value. When the count value of the counter means (2, 12) changes from the first to the second set value before the generation of the reference position signal, a control means (4, 15) sets the counter means (2, 12) to the second set value when the reference position signal is created. When the count value of the counter means (2, 12) does not change from the first to the second set value before the generation of the reference position signal, the control means (4, 15) sets the counter means to the second set value under the conditions that the counter means is at the first set value and that the reference position signal has been produced.