GB190506271A - Improvements in Electric Switches. - Google Patents

Abstract

6271. Bonnella, G. J., and Bonnella, A. March 24. Switches.-In Pressel switches for electric lighting, a sliding bridge-piece, with inclined surfaces part conducting and part insulating, connects two of three contacts in either of its two positions. An insulating-base a, Figs. 1, 2, and 3, carries three terminals b, c, d, from each of which projects a spring-pressed rounded knob e. The insulating bridge-piece f, shaped as shown in Fig. 2, carries a bent metal plate g, Fig. 4, which fits under the block f, and on two side faces. Two metal rods h, i with heads q are fastened to the block f by a screwed rod k, which passes through the block and may be made as part of one of the rods h, i. Plates screwed to the base a serve as guides for the rods h, i, and the case is slotted at o. As shown, the contacts.b, c are connected, but if the rod i be pressed inwards the contacts b, d are connected. The spring knobs e pass from one inclined surface to another with a snap action, giving a quick change from one circuit to the other. Slots v are provided for the passage of two leads, the third being fastened directly to the contact b. A modification is described for use on a single circuit, the middle terminal b being omitted. An insulating-block r and a metal block s fit together, preferably as shown in Fig. 6, the metal block s being insulated from the rod which supports it. The circuit is broken by pressing the rod i inwards.