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:
Apr. 21, 1987
Filed:
Feb. 18, 1986
Kinzi Tanaka, Kawasaki, JP;
Toru Tagawa, Kawasaki, JP;
Yoshiji Tanimoto, Tokyo, JP;
Minoru Okumura, Tokyo, JP;
Nitsuko Limited, Kanagawa, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
An extension ringing arrangement for a key telephone system wherein a plurality of key telephone sets are connected respectively through associated plurality of channel units to main equipment including a main CPU. The channel units as well as an interface unit, including a sub-CPU interconnected to the main CPU are connected in parallel to the main equipment. The interface unit is of the type used for interconnecting individual line telephone sets to the key telephone system, whereby a ringing of a selected one of the key telephone sets from a calling party is made possible, with a simple arrangement effectively utilizing existing components of the key telephone system.