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:
Jan. 14, 1986
Filed:
May. 23, 1984
Kabushiki Kaisha Toshiba, , JP;
Abstract
A terminal interface device comprises in-service detector connected to a plurality of CO lines leading to a main unit in a key telephone system and also connected to a terminal unit having a CO line interface, for detecting the in-service state of the respective lines, that is, whether the CO line is currently being used by the terminal unit and for sending an in-service signal indicative of the detected in-service state to the main unit of the system, and a switch controllably operated by a switching control signal generated from the main unit on the basis of the in-service signal and a signal indicative of the state of the CO lines in the main unit to connect one of the plural lines to the terminal unit.