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:
May. 09, 2000
Filed:
Jun. 20, 1994
Aastra Technologies Inc, North York, CA;
Abstract
An extension-in-use exclusion apparatus is for use in a telephone system. The system has a telephone device, a telephone line, and two telephone extensions connected to the line. The apparatus is connected between one extension and the telephone device. The apparatus has an exclusion controller connecting the line to the telephone device when all extensions other than the extension for the telephone device are on-hook and the telephone device extension is off-hook. The exclusion controller does not connect the line to the telephone device when another extension is off-hook and the telephone device is off-hook. A user operable switch can instruct the exclusion controller to connect the line to the telephone device when another extension is off-hook and the telephone device is off-hook. The apparatus automatically returns to exclusion mode when the telephone device returns to off-hook. A by-pass allows FSK signals to pass directly through to the telephone device. The apparatus has no polarity and is symmetrical.