Improvements in Appliances for Protecting Electric Apparatus against Currents of Excessive Strength or Voltage.

摘要

25,153. Soc. Industrielle des TÚlÚ- phones Constructions Electriques, Caoutchouc Cables. Dec. 13, 1904, [date applied for under Patents Act, 1901]. Safety apparatus for use with electric conductors. -Carbon blocks are arranged to protect an electromagnetic cut-out in a telephonic, telegraphic, or other electric circuit. A tube A of insulating- material encloses a solenoid B with a movable core C, and a non-magnetic hook D pivoted at a engages the spring b, which carries an indicator o passing through a hole in the tube A. The core C carries on its upper end a non-magnetic rod e, and on its lower end an insulating rod f. The ends of the bobbin B are of iron, and the magnetic circuit is closed by iron screws d in the iron casing E. The tube A is closed by metal caps c, c1, the instruments being connected through the caps c1, solenoid B, hook D, spring b, and cap c to the linewire. The apparatus combined with high-tension fuses is shown on a double telephonic line in Fig. 3. Two cut-outs E, supported by springs, are connected in series with fuse wires F in narrow tubes G provided with an opening q covered by a membrane r. The hole q contains an explosive, which bursts the membrane when the wire fuses, or the membrane r may be formed of such material as to change colour. The line-wires are connected to the terminals g, g1, and through the fuses F to the caps c of the cut-outs E. Lightning.. arresters are provided by connecting carbon blocks n to the caps c and other carbon blocks p to earth by the terminal T. The blocks n, p are separated by thin perforated sheets of paper or mica. The solenoid B is thus protected from lightning, which passes through the fuse F and carbon blocks n, p to earth. When an excessive current passes, the core C is drawn up to strike the hook D, and releases the spring b, breaking the circuit and causing the indicator o to pass through the casing A. The device may be re-set by pushing inwards the indicator o, and the whole apparatus is protected by a cover preferably of insulating. material.