Method and device for detection of a boil dry condition of a utensil placed on a glass-ceramic cooking surface of a cooking unit

US6300606A · kind A · utility

Assignee

• Schott Glas · DE

Inventors

• Harry Engelmann · Ingelheim am Rhein, DE
• Kurt Schaupert · Hofheim, DE

Key dates

• Filing date: Feb 3, 2000
• Grant date: Oct 9, 2001
• Expiry date: Feb 3, 2020

Classification

• Technology area (CPC H): Electricity
• CPC primary: H05B2213/07
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

The method for detecting a boil dry condition of a cooking utensil or vessel placed on a glass-ceramic cooking surface of a cooking unit having at least one cooking zone includes determination of definite criteria for occurrence of the boil dry condition based on the first and second derivatives of the cooking zone temperature, on detection of operation of the heating element power control device and the power input to the heating element in accordance with a three stage comparison of the cooking zone temperature and the shutoff temperature. When the measured cooking zone temperature is well below the shutoff temperature and after a predetermined time interval from last operation of the heating element control device by an operator, the occurrence of positive first and second derivatives signals the boil dry condition. The device for detecting a boil dry condition of a cooking utensil or vessel placed on a glass-ceramic cooking surface of a cooking unit having at least one cooking zone includes a cooking zone temperature sensor; signal generating devices for detecting operation of the heating element power control device, for energy input to the heating element and for the shutoff …