GB240243A - Improvements in electrical time switches - Google Patents

Abstract

240,243. Railing, M. J., Turner, H. C., and Sherwin, A. June 30, 1924. Clockwork actuation. - Relates to switches, which may misfunction for an interval, in which clockwork-actuated tappets A, B operate at predetermined times levers C, D to cause a switch arm H first to close and later to open. The lever D is pivoted at d to a link E pivoted to a fixed axis c and an arm F also pivoted at d can move through a small angle relatively to the lever D. The arm H is held against a fixed contact h<2> by a shouldem d<2> on the lever D engaging a projection h<3> on the am H. At a predetermined time the tappet B moves the lever D to the right releasing the arm H which is pulled down by a spring, the projection h<3> sliding along the left hand side of the shoulder d<2>, and the end of the arm F being brought against a stop c<1> on the lever C. At a later time the tappet A moves the lever C to the right causing the arm F and lever D to be moved down till the shoulder d<2> engages beneath the projection h<3>. Then when the lever C is released due to the passage of the. tappet, a spring K pulls the arms D and H back to the position shown in the Figure. Should it be desired that the switch should remain open and not function for a day, the lever F is hooked by hand over the stop C<1> during the previous day. The tappet B will then open the switch as usual but on the following day the movement of the lever C produced by the tappet A will have no effect on the lever F. When however the lever C is released its momentum will carry it past the arm F and the parts are then ready again for normal functioning.