Electrical apparatus having the appearance of a public intercom, using the telephone network to link up just one or more than one predetermined party or for controlling the opening of a door

摘要

The visible casing 1 includes: a control button 5 which controls all the normal functions of a telephone which has been programmed for one or more predetermined party numbers; the publicly inaccessible casing 2 includes a "hands free" telephone with an electronic toggle 11, a timing means 14 or 17, a means for lifting the party's receiver, an electricity supply means with a built-in backup battery 13, a keypad with memory, a tone detection means, a means of detecting the engaged tone (hang up), a means 21 acting as a relay, the connection to the telephone line 7. The invention applies in particular to chat phones and/or door openers. IMAGE