logo

For the Inventor, By the Inventor

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.:

US 5142571 B1

PDFFull Text
Date of Patent:
Aug. 25, 1992

Filed:

May. 21, 1991

Digital telephone set having an emergency switching function and

Applicant:
Inventors:

Yutaka Suzuki, Yokohama, JP;

Shigehiko Yazawa, Kawasaki, JP;

Michihiro Hamada, Yokohama, JP;

Yoshiaki Inoue, Kawasaki, JP;

Assignee:

Fujitsu Limited, Kawasaki, JP;

Attorney:

Staas & Halsey

Primary Examiner:

James L Dwyer

Assistant Examiner:

Ahmad F Matar

Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
379279 ; 379-2 ; 379 32 ;
Abstract

A digital telephone set includes a digital telephone circuit and an emergency analog circuit. Normally, the digital telephone circuit is made active so that a handset provided in common therewith is connected to a digital transmission line. In an emergency, the emergency analog circuit is made active instead of the digital telephone circuit so that the handset is connected to an analog transmission line. A dial key pad unit and a speaker are provided in common with the digital telephone circuit and the emergency analog circuit.

Find Patent Forward Citations

Suzuki, Yutaka. (1992). Digital telephone set having an emergency switching function and (U.S. Patent No. 5142571). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/5142571

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

Loading…