There is provided an antenna device of a radio apparatus, including a fed partial element, a folded partial element and an open-ended partial element. In one embodiment, an electric cable comprises a cable member, a first connector and a second connector. An oil-supply hole is formed at the orbiting scroll so that grease may be supplied into the bearing for lubrication; There is a self rotation preventing device for the orbiting scroll and another oil supply hole to that device. The metal spring may be a coil spring or a leaf spring, and may be prestressed in compression or tension.