A hinge is mounted between a cover and a base of an electronic device. A lid covers the hinge and is attached securely to the base. The hinge has a cam wing, a sleeve, a rotating shaft and a pin. The rotating shaft is mounted slidably in the sleeve. The pin is mounted slidably and transversely through the sleeve, is attached securely to the rotating shaft and slides along the outer edge of the cam wing. When the cover is pivoted to a certain angle, the pin slide at part of the cam wing having larger diameter to gradually lift up the cover so the cover is selectively distant away from the lid. Therefore, the shape of the electronic device does not need to be disfigured and the cover still does not bump against the lid.