What Are the Types of Crankshaft Position Sensors?

[McPaisley]

Crankshaft position sensors mainly come in the following three types: 1. Magnetic Induction Type. The magnetic induction speed sensor and crankshaft position sensor are installed in two layers within the distributor. The sensor consists of a permanent magnet induction detection coil and a rotor (timing rotor and speed rotor), with the rotor rotating along with the distributor shaft. The timing rotor can have one, two, or four teeth, among other forms, while the speed rotor has 24 teeth. The permanent magnet induction detection coil is fixed on the distributor body. By knowing the signals from the speed sensor and crankshaft position sensor, as well as the firing order of the cylinders, the crankshaft position of each cylinder can be determined. The rotor signal discs of the magnetic induction speed sensor and crankshaft position sensor can also be installed on the crankshaft or camshaft. 2. Hall Effect Type. The Hall effect speed sensor and crankshaft position sensor are signal generators that utilize the Hall effect. The Hall signal generator is installed inside the distributor, coaxial with the distributor rotor, and consists of an encapsulated Hall chip and a permanent magnet fixed together on the distributor plate. The number of notches on the trigger wheel matches the number of engine cylinders. When the blades on the trigger wheel enter between the permanent magnet and the Hall element, the magnetic field of the Hall trigger is bypassed by the blades, resulting in no Hall voltage and no output signal from the sensor. When the notched part of the trigger wheel enters between the permanent magnet and the Hall element, the magnetic flux enters the Hall element, increasing the Hall voltage, and the sensor outputs a voltage signal. 3. Photoelectric Type. The photoelectric crankshaft position sensor is typically installed inside the distributor. It consists of a signal generator and a signal disc with light holes. The signal disc rotates with the distributor shaft, featuring 360 light-etched slits on the outer ring to generate a signal for a 1° crankshaft rotation angle. Slightly inward, there are six evenly spaced light holes at 60° intervals, producing a signal for a 120° crankshaft rotation angle, with one wider light hole used to generate a signal relative to the top dead center of the first cylinder.