GB190517888A - Improvements in Combined Electric Switches and Automatic Circuit Breakers. - Google Patents

Abstract

17,888. Holmes, J. H. Sept. 4. switches.-Relates to combined switches and automatic circuit-breakers in which the switch cannot be held on while the automatic circuitbreaker is in action, and, when circuit is broken, the handle returns to the 'off' position ready. for reclosing. The blade of a quick-break switch is moved by a toggle which may be tripped by hand or by the core of an electro-magnet directly or through a second toggle. The hand-lever 4, Figs. 1 and 2, moves the pivot 5, which connects the toggle-levers 2, 3. The switch lever 6 carries a pin 7, which can slide in a slot 8 in the lever 3. The toggle may be tripped by the rod 10, actuated by an electro-magnet &c. on an overload. This lifts the lever 3, and enables the spring 11, or its equivalent, to move the lever 6 to break the circuit, as in Fig. 2. The circuit may also be broken by lifting the handle 4, in which case the pin 7 remains in the slot 8 in the position shown in Fig. 1. The outer lever 2 may be disconnected instead of the lever 3, or the abutment 1 may rock on a centre. The pivot of the handle 4 may be supported by a slider in guides, Fig. 4, a detent 9 engaging a projection 13 on the slider. The detent 9 may be tripped by the solenoid core &c. 10 acting on the lever 9<a>, allowing the switch to be opened by the spring 11. It may be opened by hand without moving the abutment, and a slot 4<a> provides for lost motion and a quick break. In a modification, Fig. 7, the pin 5 carries a slotted link 14, in which works a pin 15 on an arm 16 attached to the handle. The detent 17 engages with a projection 18, and is connected to an arm 17<a> loosely pivoted on the pin of the handle. In another modification, Fig. 10, a supplementary pair of toggle-levers is employed to trip the main toggle, composed of the lever 3 and the arm 2 of the handle. The end of the lever 3 has a notch 9 to engage a pivoted bar 17, and is kept in engagement by the spring 18. The bar 17 is locked by a catch rod 19 with a transverse notch through which the tail of the bar 17 passes when an overload causes the core 10 to turn the rod 19. The movement of the bar 17 unlocks the lever 3, and allows the switch arm 6 to move under the action of the spring 11. The switch may be opened by the handle 4 without disengaging the toggle-lever 3 from the bar 17.