GB601856A - Improvements in or relating to time-controlled electric switches - Google Patents

Abstract

601,856. Time switches. BAIGENT, G. M. Oct. 9, 1945, No. 26254. [Class 38 (v)] A time switch comprises a fixed dial-plate 3 bearing time indications 5, 6, and having an arcuate slot 4, in which cam members 7 are adjustably mounted to engage a lever 9, pivoted on an arm 8 fixed to a rotatable shaft 1 to operate a mercury switch 19. The switch 19 is mounted on a pivoted lever 16, one end of which bears in a groove 15 in a sleeve 14 slidable on the shaft 1. A second groove 13 on the sleeve 14 receives one end 12 of the lever 9, the other end of which is bifurcated so as to be moved in either direction by the cam 7. As the shaft 1 is rotated by a motor 24, the lever 9 is moved about its pivot by successive cams 7 to operate the switch 19. Each cam may have a squared portion co-operating with the slot 4 to prevent rotation of the cam, and a round portion to allow adjustment to its three positions, the "on " position (not shown), the inoperative position shown in Fig. 1 and the" off position (not shown). In a modification, Fig. 4, the knob 36 is only slidable along the slot, the cam 7 being rotated by first depressing, and then rotating, knob 37. In a further' modification, Fig. 7, the cam is not rotatable, its movement into its three positions being effected by a lever 44 pivoted at 49 and having an enlargement 48 working in a slot 47 in the cam 7. The position of the lever 9 may be adjusted to agree with the indications 5, 6, by the provision of a disc 25 viewed through a window 27 in the plate 3, and in one embodiment the lever 9 may be pivoted on a lug attached to the disc 25.