Patent ID: 7105781
Filing Date: 2006-09-12
Classification: H05B

Abstract:
1. Apparatus for detecting an abnormal rise in temperature as-sociated with a combination of a cooking utensil and a cooking surface overlying an electric heater, the apparatus comprising: a first temperature-responsive device adapted to monitor temperature of the cooking surface; a second temperature-responsive device adapted to monitor temperature of the cooking utensil and to provide an electrical output as a function of temperature of the cooking utensil; means for calculating first and second derivatives with time of the temperature sensed by the second temperature-responsive device over an operating temperature range of the heater; means for monitoring the first derivative of time so as to determine stabilisation of the first derivative within stabilising threshold limit values for a predetermined time; and means to compare, once stabilisation has been detected, the first and second derivatives with first and second predetermined threshold values and to detect an abnormal rise in temperature when the first and second predetermined threshold values are exceeded.