The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 21, 1981
Filed:
Jan. 25, 1979
Koichi Sekiguchi, Asaka, JP;
Hikaru Takematsu, Higashikurume, JP;
Kazutada Tatsukura, Tokorozawa, JP;
Iwasaki Tsushinki Kabushiki Kaisha, Tokyo, JP;
Abstract
A key telephone system adapted to selectively connect a plurality of key telephone sets to a plurality of CO lines through a key service unit and pluralities of talking lines and control lines and provided with a calling device in at least one of the key telephone sets, in which automatic holding of the CO line is enabled upon depression of a calling key. In case of transferring the incoming call from a receiving key telephone set to a called one of the other key telephone set, depression of the individual calling switch automatically starts calling of the called key telephone set and enables the called party to recognize the incoming call by means of lamp indication and answer the calling CO line. The number of cable conductors interconnecting the key service unit and the key telephone sets is effectively reduced.