GB172036A - Improvements in and relating to electric heaters for heating liquids - Google Patents

Abstract

172,036. Marks, E. C. R., (Langguth & Haar). May 21, 1920. Heating by electricity; electric radiators.-An electric heater for liquids in which the heating- element may be entirely removed without affecting the liquid-containing part of the heater, comprises a tank 9 of round, square, radiator, or other shape having a base with a tapered recess in which wedge-shaped heating-element is inserted. The recess is formed in a metal body 13 which is formed with a flange 17 adapted to be screwed to the base of the tank. The resistance 10 is tightly pressed between two tapered metallic plates 11, 12 and is held in the tapered recess by screws 15 and a closing-plate 16. The current through the resistance is controlled by a switch 18 operated by the dilation and contraction of a liquid contained in the space between two tubes the inner tube being flexible and carrying a rod 20 pivoted to a lever 22. The lever 22 is pivoted on a standard 31 rising from the base plate 30 of the switch and is provided at each side with an abutment through which the screwed stem of a hook passes. Springs 24 connect these hooks with hooks on a U-shaped switch member 23 pivoted in brackets 32 and carying a bridge piece 33. Expansion of the liquid raises the rod 20 moving the lever 22 until the axes of the springs pass the pivot of the switch member 23. The n,ember 23 then lifts and the circuit remains open until the rod 20 falls sufficiently to bring the axes of the springs below the pivot of the switch member again. By adjusting the tension of the springs the temperature at which the switch is operated may be varied. The inlet 26 for the water or other liquid to be heated is so situated that the flow is directed first on to the thermostat and then on to the heating-element.