Crankshaft position detection device and crankshaft signal wheel

The invention discloses a crankshaft position detection device which comprises a crankshaft signal wheel, a sensor and a controller, wherein a gear teeth lacking region, two standard gear teeth regions and a narrow gear teeth region are arranged on the periphery of the crankshaft signal wheel; the two standard gear teeth regions are used for separating the gear teeth lacking region from the narrow gear teeth region; a plurality of standard gear teeth are uniformly distributed on each standard gear teeth region; the gear teeth lacking region lacks one or a plurality of gear teeth; a plurality of narrow gear teeth are uniformly distributed on the narrow gear teeth region; each narrow gear tooth is narrower than each standard gear tooth; the distance between two tooth crests on the narrow gear teeth region is smaller than that on the standard gear teeth region; the sensor is mounted on the periphery of the crankshaft signal wheel and is used for outputting pulse electric signals to the controller with the rotation of the crankshaft signal wheel; and the controller distinguishes the crankshaft position according to the space change of the falling edges of the pulse electric signals output by the sensor. The invention further discloses the crankshaft signal wheel. The crankshaft position detection device and the crankshaft signal wheel can improve the speed for distinguishing the crankshaft position.