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. 26, 1994
Filed:
Jul. 10, 1992
Applicant:
Inventors:
Masashi Hiraiwa, Yokohama, JP;
Yoshiaki Asambo, Yokohama, JP;
Assignees:
Hitachi, Ltd., Tokyo, JP;
Hitachi Software Engineering Co., Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ; H04M / ;
U.S. Cl.
CPC ...
379219 ; 379230 ; 379279 ;
Abstract
A switching control system is provided for an electronic switcher employing a common channel signalling. This system is designed to keep the common channel signalling for a speech path in parallel to the associated signalling system, invalidate the speech information in the associated signalling system for a speech path if the signal link is in a normal state and control the speech path in the common channel signalling system, and if failure takes place on the signal link, control the speech path in the associated signalling system.