ES363641A1 - Time switch - Google Patents

Abstract

An insulating frame 13 comprises a front portion 29 supporting a time switch mechanism in an insulating housing (11, Figs. 1, 2, 3, not shown) and a rear portion (30, Fig. 6, not shown) which supports a synchronous motor (26) geared to a pinion 49 meshing with a cupshaped gear 47 having a boss 46 coupled to a shaft 56 by a helical spring friction clutch 55. This allows manual setting by a knob (34, Figs. 1, 2, 3, 6 and 10, not shown) which is integral with a twenty-four hour time dial (32) secured to the front end of shaft 56, but removed in Fig. 11 for clarity. Angularly adjustable "on" and "off " arms (35, 36) mounted on the time dial (32) for clockwise rotation carry respective lugs 85 and 86 which at preset times respectively engage the ends of forwardly-extending arms 87, 88 of quadrantal bell-crank levers 89, 90, loaded by springs 105, 106 to cause stepping of a rotary contact actuator 114. When lug 85 engages arm 87 spring 105 is stressed and the end 139 of the other arm of bell-crank 89 rides up and passes over the sloping face 137 of a sawtooth projection 135 on a disc-like portion 134 of actuator 114. When lug 85 leaves the arm 87 the bellcrank 89 snaps back, due to spring 105, and the end 139 engages the steep face of tooth 135 to turn the actuator 114 nearly 90 degrees. Completion of the 90 degree step, and location of actuator 114, is provided by a spring-urged dog (147, Figs. 13 and 16, not shown), which co-operates with a four-lobed portion 145 of actuator 114. A two-lobe cam 25 near the upper part of actuator 114 is thus turned to allow a contact on spring blade 24 to engage a fixed contact carried by terminal connector 119, and a sawtooth diametrically opposite to the tooth 136 on the upper side of disc 134 is simultaneously brought into position to be subsequently engaged by the end 140 of bell-crank 90 when " off " lug 86 acts on arm 88 whereupon the actuator 114 is snapped another 90 degrees rotation and cam 25 moves blade 24 to open the contacts (as in Fig. 12, not shown). An edgewheel 37 is coupled to actuator 114 by gears 158, 157 for manual operation of the contacts and carries ON and OFF indicia (Figs. 4 and 14, not shown). The shaft 56 may be manually moved axially by its knob (34) between two positions, located by a wire spring (63, Figs. 6 and 10, not shown) entering one of two circumferential grooves (61, 62), and when in the forward position renders the lugs 85, 86 ineffective.