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:
Sep. 18, 1990
Filed:
Apr. 04, 1988
Masanobu Shimanuki, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A control system for a plurality of telephone sets connected as branched to a central office line allows extension calling, privacy function setting and hold releasing operations between the telephone sets. Each of the telephone sets in the branched connection comprises keys through which a control data corresponding to a desired control operation is inputted, a transmission circuit for sending to the central office line a control signal corresponding to the control data inputted by the keys, a reception circuit for receiving the control signal from the line, and a control circuit for performing a predetermined control operation on the basis of the control signal received by the reception circuit, whereby the respective operations of the telephone sets are mutually controlled on the basis of the control signal.