Patent ID: 7640902

Claim:
A camshaft adjuster according to the vane-type motor principle, comprising: a stator which has at least two protrusions facing a center of the stator, a rotor which has at least one vane located in a vicinity of the at least two protrusions and which is angularly movable, said rotor having a first and a second planar face, at least two contra-rotating hydraulic regions being formed between said at least one vane and the at least two protrusions by an angular movement of the rotor, and channels to the hydraulic regions, one of the channels being formed at least partially by a central screw passage of the rotor, said central screw passage of the rotor accommodating a central screw for attaching the rotor to a camshaft and having a diameter that is larger than a diameter of said central screw, wherein: the rotor is provided as a composite system of at least two components, a flat cover and a rotor core which upon contact with each other form a covered channel portion parallel to one of said planar faces, and the flat cover sealingly covers at least one point of the rotor which is in contact with both a stationary part of the camshaft adjuster and a moving part of the camshaft adjuster, said moving part of the camshaft adjuster including at least one of the camshaft, a trigger wheel and a camshaft adjuster cover.