Rotation angle detecting device for a camshaft provided in an internal combustion engine

A rotation angle detecting comprising:

• a sensor having a first yoke made of a magnetic material on which a magnet is mounted, a second yoke made of a magnetic material on which a magnetic flux detector is mounted, the second yoke being disposed opposite to said first yoke with a preset space set between the first and second yokes, and a housing for supporting said first yoke and said second yoke;
• and
• a vane having a wall portion, said vane being secured directly to a camshaft of an internal combustion engine and positioned relative to said first and second yokes so that said wall portion can pass through said preset space between said first yoke and said second yoke as the vane rotates with the camshaft;
• wherein said housing is mounted on said internal combustion engine;
• wherein positioning of the housing of said sensor to the internal combustion engine is executed with positioning pins provided on the housing of said sensor or the internal combustion engine, said positioning pins being positioned a predetermined radial distance from a center axis of said camshaft;
• and
• wherein a rotation angle of said shaft of the internal combustion engine is detected in accordance with a signal provided at said magnetic flux detecting device by passage of the wall portion of said vane through said space which blocks the passage of magnetic flux generated by said magnet.