Patent · US Expired

Door intercom

US6233328A · kind A · utility

29Cited by
13References
8Claims
0Family size

Inventor

Key dates

Filing dateDec 22, 1997
Grant dateMay 15, 2001
Priority date
Expiry dateDec 22, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M1/0291
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An automatic door answering system comprises a door intercom system, a recording machine, a telecommunication system, first, second and third interfaces, and a microprocessor-based switching device. The switching device is coupled to the door intercom system, the recording machine, and the telecommunication system by way of the first, second, and third interfaces, respectively. The switching device switches back and forth between coupling the door intercom system to a telecommunication system, coupling the door intercom system to a recording machine, and coupling the telecommunication system to the recording machine. If the recipient of a visitor is not available, the automatic door answering system establishes a communication link between the visitor and the recipient using the door intercom system and the telecommunication system. If the recipient of the visitor is not available, the automatic door answering system allows the visitor to record a message for the recipient. The message may be time-stamped to provide additional information. The recording system may also be used to play messages to the visitor and to request information from the visitor, such as the identity of the r…

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