Patent ID: 7652229
Filing Date: 2010-01-26
Classification: H05B

Abstract:
1. An electrical heating arrangement comprising: a cooking plate ( 4 ) having an upper surface ( 6 ) for receiving a cooking utensil ( 8 ), and a lower surface ( 10 ); an electric heater ( 12 ) incorporating at least one electric heating element ( 20 ), the heater being supported in contact with the lower surface of the cooking plate; and a temperature sensor assembly ( 30 ), wherein the temperature sensor assembly comprises: an elongate substantially planar substrate ( 32 ) located in the heater and extending at least partially across the heater from a peripheral region ( 34 ) at least to a central region ( 36 ) of the heater, the substrate having an upper surface ( 38 ) located in contact with, or in close proximity to, the lower surface of the cooking plate, and also a having a lower surface ( 66 ), the upper and/or lower surface or surfaces of the substrate being provided with at least one first temperature-sensitive electrical resistance element ( 40 ) of film form at a first region ( 42 ) of the substrate proximate the peripheral region of the heater, the upper and/or lower surface or surfaces of the substrate being provided with at least one second temperature-sensitive electrical resistance element ( 54 ; 54 A; 54 B) of film form at a second region ( 56 ) of the substrate proximate the central region of the heater, the first and second temperature-sensitive electrical resistance elements being provided with electrical connecting leads ( 44 , 46 , 58 , 60 ) for electrical connection to external control circuit means ( 28 ) for the heater; at least one support member ( 70 , 102 ) secured to the substrate and underlying at least the first region of the substrate; and thermal insulation means ( 74 ) interposed between at least the lower surface of the substrate and the at least one support member substantially only at the first region of the substrate.