GB1513891A - Energy regulators for electric cooking or heating appliances - Google Patents

Abstract

1513891 Thermal switches K FISCHER 9 May 1975 [10 May 1974 6 Sept 1974] 19547/75 Heading H1N An energy regulator for an electric cooking or heating appliance comprises a temperature responsive expansion element 44 for actuating a snap action switch 45 having a snap action spring 48 whose actuation point 49 has a path of movement of less than 0À02 mm, and a manually operable adjusting member 27 for adjusting, via two spring biased levers 28, 33, the position of the expansion element 44 so as to adjust the energy fed to the appliance. One of the levers 28, 33 is composed wholly (228, Fig. 9, not shown) or partly (34 as shown) of a bimetal to provide temperature compensation. The levers 28, 33 may act on an expansion rod 44 containing an insulated resistance wire through which current flows when the switch 45 is closed so as to heat the rod 44. The expansion movement may be transmitted to the switch 45 by the sleeve of the rod 44, as shown, or by the resistance wire (Fig. 7, not shown). A shaft 15 carrying the adjusting member 27 also carries a cam (22) (Fig. 3, not shown) for activating contacts (23, 24). The expansion element may alternatively comprise a bimetal member (144) (Fig. S, not shown) riveted to the lever 33 and acting at a free end on the snap switch 45 via a ceramic rod (44<1>). The bimetal (144) is heated by current passing through it or by an external heater.