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:
Mar. 04, 2014
Filed:
May. 09, 2011
Applicant:
Takuma Aoshima, Shizuoka, JP;
Inventor:
Takuma Aoshima, Shizuoka, JP;
Assignee:
NEC Access Technica Ltd, Shizuoka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M 3/00 (2006.01); G08B 3/10 (2006.01);
U.S. Cl.
CPC ...
Abstract
A call signal generating device, whose pair of output terminals is connected to a telephone set, includes a rectifier rectifying an inputted high frequency signal and maintaining an output polarity in one of two polarities; and a polarity reverser generating a call signal by periodically reversing the output polarity of the rectifier and supplying it to the telephone set via the pair of output terminals.