A rotating mechanism comprises a retaining plate having a track and a groove, both of which are defined in the retaining plate and parallel to each other; a rotating plate being capable of rotating in a plane parallel to the plane of the retaining plate by a shaft, the rotating plate has a slot and a slit, both of which are defined in the rotating plate and extending along a imaginary line; a biasing member including a first biasing member end and a second biasing member end; a peg retained on the first biasing member end and extending into the groove and the slot; a rail retained on the second biasing member end and extending into the track and the slit.