US Patent 7486974 Hinged device

A hinged device. A first frame comprises a first contact surface and a first through hole. A second frame rotatably connects to the first frame. A second cam is movably disposed in the second frame, comprises a second contact surface abutting the first contact surface and a second through hole. When the first and second frames are rotated oppositely around a first direction, the second cam moves along the first direction. An elastic member is disposed between the second frame and the second cam, providing a first elastic force on the second cam. An electrical transmission media passes through the first and second through holes.