136,287. King, J. Dec. 18, 1918. Mine signalling systems; order apparatus. - Signalling-apparatus designed particularly for mines comprises a number of lamps illuminating stencilled or other signs which form the front of compartments in a locked frame in which the lamps are situated. A bell is also provided for giving a number of rings corresponding with the visual signal. The lamps are selected by turning the handle of a switch, and the bell is rung by a separate device in the switch. In the switch shown in Fig. 7, leads i1, l5, &c. from the lamps are connected to contacts 1, 5, &c., and a circuit is completed through the contact x on the switch arm v through a battery to the common lead from the lamps. The bell leads are connected through semicircular wires s, t to contacts z, 6, which can be brought together by depressing the hinged part y. In the switch shown in Fig. 8, the common lead from the lamps is connected to a ring 16 mounted on an insulating-disk 13. Connexion is thus made through a brush 23 with a stud 17 connected to one of the lamps and selected by turning the handle 28 till the pointer 25 registers with a numbered notch. The bell is rung by depressing the knob 32, when a plate 34 bridges across the two sides of the bell circuit, which are connected to the contacts 35, 36.
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