Variable valve timing camshaft

A variable valve timing camshaft which is connected to a continuous variable valve timing apparatus having a rotor and a stator which are adapted to relatively rotate with each other and is operated to vary open/close timing of a valve, the variable valve timing camshaft comprising:

• a non-control camshaft coupled to the continuous variable valve timing apparatus, having a first drive gear rotating together with the rotor and a second drive gear rotating together with the stator, the non-control camshaft rotating according to rotation of an engine;
• a control camshaft having an outer shaft rotating according to one of the first drive gear or the second drive gear, an inner shaft rotatably inserted into the outer shaft and rotating according to the other of the first drive gear or the second drive gear, an outer cam fixed to the outer shaft, and an inner cam fixed to the inner shaft, wherein a phase along a circumferential direction is varied between the outer shaft and the inner shaft according to relative rotation of the rotor and the stator;
• and
• a limiting device limiting end play of the inner shaft, wherein the limiting device includes:
• a locking pin penetrating the outer shaft along a radial direction and to be inserted into the inner shaft;
• a locking groove formed along an external circumference of the inner shaft such that the locking pin is inserted thereto;
• and
• a locking pin hole formed at the outer shaft such that the locking pin penetrates the outer shaft.