Crankshaft position sensing in a combustion engine
AssigneeScania CV AB (publ)
InventorHåkan Fröjdh
Life of this patent
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Abstract
An arrangement for a combustion engine with a control system for determining the engine's crankshaft position and direction, including two independent sensors (S1, S2), each of which cooperates with a group of rotational position markings (r). The two sensors (S1, S2) are crankshaft sensors and they are mutually displaced (a/A) in the rotation direction relative to the midpoints of the respective rotational position markings so that during crankshaft rotation the direction of rotation can be determined by comparison of the sensor signal sequences from the two sensors.
Claims10
An arrangement for a control system for a combustion engine for determining a position and rotation direction of an engine crankshaft, the arrangement comprising:
- an engine crankshaft which is rotatable;
- a group of rotational position markings arrayed around the crankshaft;
- first and second independent crankshaft sensors for sensing the rotation of the rotational position markings past each of the sensors, the sensors being located substantially opposite each other around the crankshaft but displaced such that when the first sensor is directly opposite a midpoint or a first rotational position marking, the second sensor is located a predetermined distance from a midpoint of a second rotational position marking that is 180 degrees from the first rotational position marking, the direction of rotation of the crankshaft being determined by comparing respective sensor signals from the first and second sensors;
- and
- a gap in the rotational position markings around the crankshaft, so that the gap is sensed by the first or the second sensor and enables a detection of the rotational position of the crankshaft.
An arrangement for a control system for a combustion engine for determining a position and rotation direction of an engine crankshaft, the arrangement comprising:
- an engine crankshaft which is rotatable;
- a group of rotational position markings arrayed around the crankshaft;
- first and second independent crankshaft sensors for sensing the rotation of the rotational position markings past each of the sensors, the sensors being located substantially opposite each other around the crankshaft but displaced such that when the first sensor is directly opposite a midpoint or a first rotational position marking, the second sensor is located a predetermined distance from a midpoint of a second rotational position marking that is 180 degrees from the first rotational position marking, the direction of rotation of the crankshaft being determined by comparing respective sensor signals from the first and second sensors;
- and
- a gap in the rotational position markings around the crankshaft, so that the gap is sensed by the first or the second sensor and enables a detection of the rotational position of the crankshaft, wherein an engine flywheel is disposed on and rotates with the crankshaft and the rotational position markings comprise recesses spaced apart in the engine flywheel.
An arrangement for a control system for a combustion engine for determining a position and rotation direction of an engine crankshaft, the arrangement comprising:
- an engine crankshaft which is rotatable;
- a group of rotational position markings arrayed around the crankshaft;
- first and second independent crankshaft sensors for sensing the rotation of the rotational position markings past each of the sensors, the sensors being located substantially opposite each other around the crankshaft but displaced such that when the first sensor is directly opposite a midpoint or a first rotational position marking, the second sensor is located a predetermined distance from a midpoint of a second rotational position marking that is 180 degrees from the first rotational position marking, the direction of rotation of the crankshaft being determined by comparing respective sensor signals from the first and second sensors;
- and
- a gap in the rotational position markings around the crankshaft, so that the gap is sensed by the first or the second sensor and enables a detection of the rotational position of the crankshaft, wherein the predetermined distance differs from zero, from one-half of a spacing between adjacent rotational position markings, and from even multiples of the spacing between adjacent rotational position markings.
Dependencies are inferred from the claim text.