GB758132A - Improvements in or relating to electric immersion heaters - Google Patents

Abstract

758,132. Electric immersion heaters. HOTPOINT ELECTRIC APPLIANCE CO., Ltd. April 12, 1955 [April 13, 1954], No. 10795/54. Class 39(3). Two immersion heating elements are selectively energisable for heating the lower and upper regions respectively of the contents of a vessel, and are under control of a single thermostat responsive to temperature in said upper region. In Fig. 2, a thermostat T mounted between the tubes of heating elements U, L, is adjustable primarily by rotation of a boss T<SP>1</SP> provided with an indicator and fingerpiece T<SP>3</SP>. A member T<SP>5</SP> for "fine " adjustment of the thermostat is rotatable by a switch knob S<SP>2</SP> by means of a pin and arm S4, T4, a switch S permitting either element L or element U to be energized or both elements to be switched off. Upon turning the switch knob from "high" to "low" elements U, L, are respectively disconnected and connected and the thermostat member T5 is rotated thus setting the thermostat say 5‹ F. higher than it was when the switch was in the "high" position. Cold water in the lower region of the container is thus able to attain a temperature approximately equal to the initial temperature of the hot upper region before the lower heating element L, is deenergised by actuation of the thermostat. In a similar manner, change of the switch from "low" to "high" position adjusts the thermostat to a setting 5‹ F. lower for the element U than for the element L. In a modification, Fig. 1, a switch S<SP>1</SP> of the push bar kind is operated by a sliding U-shaped member B carrying an arm A which engages a peg P for rotating a spring-loaded blade D engaging a temperature adjusting slot for "fine" adjustment of a thermostat T, H. Main adjustment of the thermostat is by means of a knob K connected by friction drive -to the blade D.