Radiant heater in a cooking hob with a thermal switch

- A radiant heater adapted to an electric cooking hob with a glass ceramic type hotplate and at least said radiant heater comprising:

• an insulating base (104) substantially parallel to the top hotplate (2), and a heating resistor (5) extended according to a given geometric configuration supported on the central surface area (104a) of the insulating base, a peripheral wall of the insulating ring (6) defining a heated plate area (2a) and an air cavity (13) along with a central surface area (104a) in the insulating base, an outer cover or metal tray (3) forming with said insulating ring (6) an outer peripheral wall (3,6) of the radiant heater, a thermal switch (107) of the bimetal sensor type built into the radiant heater, and an electrical power connector (8) fixed in said peripheral wall (3,6).
• wherein the bimetal sensor (107c) of the thermal switch is provided with a heat-receiving metal base (107b,107d) for the detection of a temperature value (ST) in the bimetal sensor (107c) in correspondence with the actual temperature (ZT) of the plate area (2a), and with an electrical contact (109) associated with the bimetal sensor (107c) which is set at a switching point (SWC′,SWO′) correlated to a low temperature range (TU) of the plate area (2a) during the two radiant heater heating and cooling processes, for the switching of an indicator of the condition of hot plate (2a), and
• said thermal switch (107), having a compact body (107a) of heat-resistant ceramic material, is fixed in a given position (A,S) in said air cavity (13) below the heated plate area (2a), such that the compact body (107a) of the switch is supported on said central insulating surface area (104a) insulated thermally from said peripheral wall, and with said metal base (107b,107d) oriented towards at least one segment of the heating resistor (105a), and positioned very close (A) to a segment of said heating resistor (105a) or substantially in direct thermal contact with it, for the direct reception of the heating radiation on the bimetal sensor (107).