Process and arrangement for recognizing the rotating direction of an internal-combustion engine

An arrangement for carrying out a process for recognizing a rotational direction of an internal-combustion engine, which process assigns a defined first crankshaft position to a defined camshaft position, said defined first crankshaft position existing when the internal-combustion engine rotates in reverse;

• assigns a defined second crankshaft position to the same defined camshaft position, said second crankshaft position existing when the internal-combustion engine rotates in a forward direction;
• and queries the assignments to recognize the rotational direction of the internal-combustion engine, the arrangement comprising:
• a crankshaft angle sensor interacting with a generator gear mounted on a crankshaft and having a plurality of teeth;
• a camshaft angle sensor interacting with a generator gear mounted on a camshaft and having at least one tooth;
• and
• an electronic internal-combustion engine control unit having a storage device, said control unit receiving and processing signals from the crankshaft angle sensor and the camshaft angle sensor;
• wherein a defined first crankshaft angle portion is assigned to at least one defined signal edge of the signal from the camshaft angle sensor caused by a tooth of the camshaft generator gear, said defined first crankshaft angle portion being determined by a tooth portion of the crankshaft generator gear which exists when the internal-combustion engine rotates in a forward direction;
• and
• wherein a defined second crankshaft portion determinable by a further tooth portion which exists when the internal-combustion engine rotates in a reverse direction is assigned to the same defined signal edge of the camshaft angle sensor, wherein the internal-combustion engine control unit queries the assignments stored therein to recognize the rotational direction of the internal-combustion engine.

A software product for recognizing a rotational direction of an internal-combustion engine, the product comprising a computer readable medium having stored thereon a program having code segments that:

• assign a defined first crankshaft position signal which exists when the internal-combustion engine is rotating in a reverse direction to a defined camshaft position signal;
• assign a defined second crankshaft position signal which exists when the internal-combustion engine rotates in a forward direction to said defined camshaft position signal;
• and
• queries said assignments to recognize the rotation direction of the internal-combustion engine.

A computer program embodied on a computer-readable medium for recognizing a rotational direction of an internal-combustion engine based on crankshaft angle sensor signals and camshaft angle sensor signals, the computer program comprising code segments that:

• determine when the internal-combustion engine begins to rotate by detecting a crankshaft angle sensor signal;
• determine a crankshaft angle based on a reference mark in the crankshaft angle sensor signal;
• detect a defined position of a camshaft angle sensor signal;
• determine whether the defined position of the camshaft angle sensor signal corresponds to a position of the crankshaft angle sensor signal indicative of a forward rotation or a rearward rotation of the internal-combustion engine;
• and
• recognize the rotational direction of the internal-combustion engine based on the defined position of the camshaft angle sensor signal relative to the crankshaft angle sensor signal.