GB534395A - Improvements in and relating to electric switches for electric cookers - Google Patents

Abstract

534,395. Interrupters. TURNER, C. A., and DIAMOND H SWITCHES, Ltd. Nov. 24, 1939, No. 34932/38. [Class 38 (v)] [Also in Group XXXV] A motor-driven shaft 4 carries a cam 5 whereby a spring blade 6 carrying a contact 8 is caused to vibrate. A manually-operated shaft 12 carries a pair of cams 11, 13 of which 11 can be moved from the off position, Fig. 3, so as to bring a contact 10 on a further spring blade 9 into the path of movement of contact 8 so as to close the circuit to the heating element 24 of a cooker. The duration of the contactengagement varies in accordance with the angular displacement of 11 and can be progressively varied unti, when the hump on the cam engages the blade, the contacts are in continuous engagement. In this position, a further hump on cam 13 engages a blade to open the motor circuit at 14, 15. The off position of contacts 10, 14 is determined by the engagement of sprung balls. 17 with dents in a cam 16 on shaft 12. The shaft 4 rotates at two or three revolutions per minute and may operate a number of such switches mounted, 'with the motor and reducing gearing on a common frame, Fig. 4 (not shown). The shaft 12 may have a handle carrying suitable markings or temperature indications. A timing- device may be added so as to initiate the cooking operation at a certain time.