Publication: Electrical World
New York, NY, United States
Broomhall's Insulators and Pole Caps.
The cuts illustrating this article will give an excellent view of the inventions by Mr. George L. Broomhall, of Paterson, N. J., of a cap to protect the tops of telegraph poles from the action of the weather, combined with screw-pins, to which glass insulators can't be easily and firmly adjusted, and extra points for securing wires be thus obtained at a portion of the pole not often utilized.
Fig. 1 represents the flat cap, covering the entire top of the pole. From its depending flange project lateral screw-pins, on which, as on the vertical pin in centre of cap, the glass insulators are shown as fitted. The flange, which sets closely to the properly rounded top of the pole, prevents splitting, and the wires bracing from these three newly provided positions give additional firmness to the shaft. The cap is secured by a screw from its inner surface, which is sunken in the timber and by spikes through holes provided; or by pointed pins in place of the screw and inward projecting lugs on the inner circumference of the dependent flange.
Fig. 2 is a modification of the same idea and for like purposes. A metallic cap, with a vertical screw-pin to receive the glass insulator, is fitted on the top of the pole; the pins or prongs are driven into the pole, and it is further fastened by spikes through the holes provided in the plate.
The plates may be cast flat, as in Fig. 1, or conical, shown by Fig. 2, and there are several other modifications described and claimed by the inventor in his specification whereby his caps and pins can be applied to poles under any and all circumstances and positions, insuring, by their use, preservation and increased firmness for the pole and economy of pole surface with rapid adjustment and perfect insulation of wires.
Though these caps are of metal and sufficiently heavy and strong to bear any possible strain upon them, they can be furnished at a comparatively low cost and the advantages offered are worthy the consideration of all interested in aerial wire lines.