Patent · US Expired

Key telephone system intercom arrangement

US3976847A · kind A · utility

12Cited by
5References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 12, 1975
Grant dateAug 24, 1976
Priority date
Expiry dateNov 12, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M9/10
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A key telephone system is disclosed in which intercom calls may be answered "hands-free" at the called station. Intercom calls are originated in the standard manner, with the subscriber picking up the handset at the calling station and dialing the number of the called station. A voice communication path is established through the station selector to the telephone set represented by the dialed number. DC bias on this communication path through the station selector activates a loudspeaker and microphone arrangement in the called telephone set. The called party may thus converse "hands-free" with the calling party by utilizing the activated loudspeaker and microphone of the station set, and need not manipulate the station set for the duration of the conversation.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.