GB824687A - Improvements in electric time switches - Google Patents

Abstract

824,687. Time switches. HORSTMANN GEAR CO. Ltd. Nov. 27, 1957 [Dec. 14, 1956], No. 38226/56. Class 38 (5). The switch comprises a rotating dial plate with adjustable " on " and " off " tappets, the " on " tappet being engageable with a lever to move the switch " on," and a spring-loaded retaining lever which holds the switch in that position in the event of a second engagement of the lever by an " on " tappet before the switch is moved " off by an "off" tappet. When the " on " tappet 13 is moved clockwise to engage a lever 14 pivoted at 15, the lever tilts counter-clockwise and lowers a lever 17 pivoted thereto at 19, this action stressing a spring 38 attached to lever 17 and a lever 34, and positioning a step 20 on lever 17 below an arm 40 of the lever 34 pivoted to a base-plate 4 at 36. Eventually tappet 13 disengages the lever 14 which is rotated clockwise by spring 38 into engagement with a stop 46. At the same time, lever 17 is raised and carries lever 34 with it. This movement of the lever 34 causes a button 50, carried at the rear of plate 4 by a pin 48 on the lever 34, to allow a contact blade to engage a fixed contact (Fig. 4, not shown). Also, the arm 40 is raised above a catch 29 on a lever 27 which is thus pivoted clockwise by a spring 31 to latch the arm 40, even though the step 20 on lever 17 may be moved down again by a second engagement of lever 14 by the same or a further " on " tappet. The switch is opened when an "off" tappet 11 engages a lever 12 which carries a pin 22 located in a slot 18 in lever 17 and an arm 26 which engages an arm 27<SP>1</SP> of lever 27 so that steps 20 and 29 are both removed from below lever 34 which is tilted clockwise by spring 38. The mechanism may be applied to the switch of Specification 744,612. The switch may be manually tripped open by moving to the left an arm 43 on a lever 41, thereby causing an arm 41<SP>11</SP> thereon to engage an arm 25 on the lever 12 which is thus moved to release the lever 34. Movement of the arm 43 to the right causes an arm 41<SP>1</SP> on lever 41 to tilt lever 34 counter-clockwise to reclose the contacts, the lever 34 becoming latched as before. Specifications 329,633, 331,083, [both in Class 38 (v)], 373,554 and 500,670 also are referred to.