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. 08, 1991
Filed:
Jun. 29, 1989
Jin-Pyo Eun, Seoul, KR;
SamSung Electronics Co., Ltd., Suwon, KR;
Abstract
A break-in method and a circuit in a key system for switching a key system to a conference-call state by use of a conference-call circuit is disclosed in the invention. In the break-in method, when an attendant perceives a telephone subscriber on the line, the attendant breaks in forcefully upon the subscriber's call currently on the line, changing the present call to a conference call. Thereafter, if the attendant hangs on the phone, the subscriber having waited for being switched breaks into the conference-call replacing the attendant. To achieve the improved method the inventive subject includes: a microprocessor MPU for controlling the key system; a subscriber circuit SBC for interfacing a state of an extension-line subscriber ST1 to STn with a main system 100; an office line circuit OLC for interfacing office-line codes Co1, Co2 with the main system 100; a switching circuit S/W for providing and switching a line controlling under control microprocessor MPU; a conference-call circuit CFC for providing telephone subscribers with the conference-call operation by means of controlling microprocessor MPU; and a memory MRY for reading and writing data by controlling under control microprocessor MPU.