The types of crankshaft position sensors are as follows:
1. Magnetoelectric induction type:
Magnetoelectric induction speed sensor and crankshaft position sensor are installed on the upper and lower floors of the distributor. The sensor consists of a permanent magnet induction detection coil and a rotor (timing rotor and speed rotor) rotating with the distributor shaft. The timing rotor has one, two or four teeth, while the speed rotor has 24 teeth. The permanent magnet induction detection coil is fixed on the distributor body. If we know the speed sensor signal, the crankshaft position sensor signal and the working sequence of each cylinder, we can know the crankshaft position of each cylinder. The rotor signal disk of the magnetoelectric induction speed sensor and the crankshaft position sensor can also be installed on the crankshaft or camshaft.
2. Hall effect formula:
Hall effect speed sensor and crankshaft position sensor are signal generators using Hall effect. Hall signal generator is installed in the distributor, coaxial with the distributor head, and integrally fixed on the distributor through the packaged Hall chip and permanent magnet. The number of notches on the trigger impeller is the same as the number of engine cylinders. When the blade on the trigger impeller enters between the permanent magnet and the Hall element, the magnetic field of the Hall trigger is bypassed by the blade, so there is no Hall voltage and the sensor has no output signal. When the gap on the trigger impeller enters between the permanent magnet and the Hall element, the magnetic field lines enter the Hall element, the Hall voltage rises, and the sensor outputs a voltage signal.
3. Photoelectric type:
The photoelectric crankshaft position sensor is usually installed in the distributor and consists of a signal generator and a signal board with luminous holes. The signal disk rotates with the distributor shaft, and there is a 360 photoetching gap on the outer ring of the signal disk, which produces a signal with the crank angle of1. There are six 60-degree evenly distributed light holes inside, which can generate the signal of 120-degree crank angle, and one light hole is wider to generate the signal relative to 1 cylinder top dead center. 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 faces the photodiode. The signal disk is located between the light emitting diode and the photodiode. Because there are light holes in the signal disk, there is an alternating phenomenon of light transmission and light shielding. When the light beam of the light emitting diode irradiates on the photodiode, the photodiode generates voltage; When the LED beam is blocked, the photodiode voltage is 0. These voltage signals are shaped and amplified by the circuit part, that is, the signals when the crank angle is 1 and 120 are sent to the electronic control unit, and the electronic control unit calculates the engine speed and crankshaft position according to these signals.