Retractable antenna device having a rodlike antenna and a helix antenna which is electrically isolated from the rodlike antenna in the retracted condition of the antenna device

摘要

An antenna device is withdrawable from and receivable in a body of a portable radio device. A rodlike antenna is covered with a rodlike antenna cover, and a helix antenna to which an initial elastic strain is imparted is covered with a cap. A control portion of an electrically-conductive member is movably received in a groove formed in a portion of connection between the rodlike antenna cover and the cap. The rodlike antenna cover is supported on the body of the radio device. In an extended condition of the rodlike antenna, a connection portion of the electrically-conductive member is urged against the rodlike antenna by a restoring load of the helix antenna to electrically connect the spiral antenna to the rodlike antenna. In a retracted condition of the rodlike antenna, the electrically-conductive member is caused to abut against an antenna holder to be spaced apart from the rodlike antenna, thereby interrupting an electrical connection between the helix antenna and the rodlike antenna. In the retracted position of the rodlike antenna, an engagement projection of the cap is releasably engaged with a retaining pawl on the body to hold the rodlike antenna in its retracted position. With this arrangement, antenna characteristics are restrained from being degraded in the retracted condition of the rodlike antenna.