Improvements in Electric Switches suitable for use in connection with Telephonic Apparatus and for other purposes.

Abstract

Abstract 11,368. Graham, E. A. May 17. Telephones.-For use in connection with telephonic apparatus in exposed positions, such as described in Specification No. 7966, A.D. 1903, portions of mercury or other conducting-liquid are enclosed in sealed, preferably exhausted, receptacles or tubes having sealed-in wires connected to external conductors, so that different circuits are closed according to the position of the tubes. The tubes are bedded in soft material, and are enclosed with their terminals in water-tight casings of ebonite or other strong material. Fig. 2 shows the switch applied to the rotatable casing of a telephone, in which two curved glass vacuum tubes 1, 2 contain portions of mercury 3, 4 and sealed-in platinum wires 5, 5<a>, 6, 6<a>, 7, 7<a>, which are connected to terminal blocks 14 to 19. They are enclosed in a casing 9 made of two halves suitably recessed and screwed together and packed with Chatterton's composition or other material that will make a water-tight joint. Soft material 13 is placed between the tubes and the walls of their recesses, and the connections between the sealed-in wires and the terminals are also made flexible, in order to prevent strain and shock. The flexible conductors 20, 21, 22, 23, 24 lead respectively to the telephone bell, one line-wire, receiver, transmitter, and second line-wire. A connection 26 is made between the terminals 15, 17. When the casing occupies the position shown in full lines, the bell is in circuit, while in the position shown in dotted lines the transmitter and receiver take its place. The modified form shown in Fig. 3 is adapted for a hand telephone.

Inventors

• 👤 Edward Alfred Graham

Bibliographic Details