Valve duration control apparatus and engine provided with the same

An engine comprising:

• a camshaft;
• a plurality of cylinders;
• a plurality of wheel pins and a plurality of cam pins;
• a plurality of wheels mounted to the camshaft, wherein each wheel includes a wheel pin, the plurality of wheels being disposed corresponding to each cylinder of the plurality of cylinders;
• a plurality of cam portions each including a cam and a cam pin, the camshaft being inserted through the plurality of cam portions so that a relative phase angle of each of the plurality of cam portions with respect to the camshaft is variable;
• a plurality of inner brackets, wherein each inner bracket includes a first pin guide hole and a second pin guide hole, wherein each wheel pin of the plurality of wheel pins is connected to the corresponding wheel of the plurality of wheels and slidably inserted into the corresponding first pin guide hole of the plurality of first pin guide holes, and wherein each cam pin of the plurality of cam pins is connected to the corresponding cam of the plurality of cams and inserted into the corresponding second pin guide hole of the plurality of second pin guide holes, the plurality of inner brackets respectively and rotatably inserted into a plurality of slider housings;
• a plurality of cam caps each including a hinge hole, wherein the plurality of slider housings are respectively and rotatably mounted to a hinge hole of each cam cap of the plurality of cam caps;
• and
• a control portion moving the plurality of slider housings so as to change a position of a rotation center of the plurality of inner brackets relative to a rotation center of the camshaft.