Three types of camshaft crankshaft sensor(3)

The photoelectric camshaft crankshaft sensor is generally installed in the distributor and consists of a signal generator and a signal plate with a light hole. The signal plate and the distributor shaft photoelectrically rotate together. The outer ring of the signal plate has 360 photoetching slits to generate a signal with a crank angle of 1 °; a little bit inside, there are 6 light holes evenly spaced at 60 °, resulting in a crank angle of 120. ° signal, one of the light holes is wider, used to generate a signal relative to the top dead center of cylinder 1. The signal generator is installed on the shell of the distributor and consists of two light-emitting diodes, two photodiodes and a circuit. The light-emitting diode is facing the photodiode. The signal plate is located between the light-emitting diode and the photodiode. Because there are light holes on the signal plate, the phenomenon of light transmission and shading alternately occurs. When the light beam of the light-emitting diode hits the photodiode, the photodiode generates a voltage; when the light-emitting diode beam is blocked, the voltage of the photodiode is 0. After these voltage signals are partially reshaped and amplified by the circuit, they send signals when the crankshaft angle is 1° and 120° to the electronic control unit, and the electronic control unit calculates the engine speed and crankshaft position based on these signals.