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:
Jan. 10, 1995
Filed:
Aug. 09, 1991
Applicant:
Inventors:
Assignee:
Tamura Electric Works, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
379387 ; 379413 ; 379322 ;
Abstract
A power source control circuit for a telephone set, includes a power source switch, a detecting circuit, a power hold circuit, and a control circuit. The power source switch supplies an external power to the telephone set. The detecting circuit detects an off-hook operation of the telephone set or an incoming signal arriving at a line. The power hold circuit holds the power source switch in an ON state for a predetermined time period on the basis of an output from the detecting circuit. The control circuit is activated by supply of the external power and transmits an extension signal for extending the ON state of the power source switch within the predetermine time period.