US Patent 7395100 Portable communication apparatus having keys moved up/down by rotation

A portable communication apparatus equipped with up/down keys. The portable communication apparatus includes a main housing, a sliding housing adapted to slide to be opened and closed while continuously facing the main housing, a number of keys arranged in a predetermined position on the top surface of the main housing and adapted to be moved up to be exposed and moved down to be hidden, when the sliding housing is opened and closed, respectively, and an elastic body positioned below the keys to provide a force for moving them up.