Method and apparatus for rapid heat-up of a glass-ceramic cooktop

• US 6,350,968 B1
• Filed: 10/16/2000
• Issued: 02/26/2002
• Est. Priority Date: 10/16/2000
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Schnore, Austars Raymond Jr., Connolly, Allan John
• Primary Examiner(s): PAIK, SANG YEOP
• Application Number:
  US09/687,112
• Time in Patent Office: 498 Days
• Field of Search: 219/481, 219/482, 219/490, 219/492, 219/494, 219/497, 219/509, 219/510, 219/448.11, 219/448.12
• US Class Current: 219/497
• CPC Class Codes: G05D 23/1902 characterised by the use of a variable reference value
• CPC Class Codes: H05B 2213/07 Heating plates with temperature control means
• CPC Class Codes: H05B 3/746 Protection, e.g. overheat cutoff, hot plate indicator

Abstract

An apparatus for rapidly heating a cooktop is provided. The apparatus comprises a radiant heating element positioned proximate to the cooktop. A controller is provided and is connected to the radiant heating element. The controller includes a fast heat-up circuit selectively coupled to the radiant heating element. A look-up table is selectively coupled to the fast heat-up circuit. The look-up table comprises a plurality of user power levels. Each of the plurality of user power levels is correlated to a respective user-selected temperature. The apparatus further comprises a user power input device connected to the controller. The user power input device also allows selection of at least a first of the plurality of user power levels wherein the first power level corresponds to a first respective user selected temperature in the look-up table. A temperature sensor is connected to the controller for measuring a temperature of the cooktop.

Claims

1. An apparatus for rapidly heating a cooktop, the apparatus comprising:

a radiant heating element positioned below the cooktop;

a controller connected to the radiant heating element, the controller comprising;

a first switching device connected to the radiant heating element;

a fast heat-up circuit connected to the first switching device, the fast heat-up circuit comprising;

a proportional-plus-integral (PI) controller connected to the first switching device;

a minimum selector having a minimum selector output, the minimum selector connected to the PI controller and the minimum selector output connected to the first switching device; and

an anti-wind up controller connected to the PI controller and the minimum selector output;

a second switching device connected to the PI controller; and

a look-up table connected to the second switching device, the look-up table comprising a plurality of user power levels wherein each of the plurality of user power levels correlates to a respective user-selected temperature;

a user power input device connected to the controller and allowing selection of at least a first of the plurality of user power levels wherein the first user power level corresponds to a first respective user-selected temperature in the look-up table; and

a temperature sensor connected to the controller to measure a temperature of the cooktop.

2. The apparatus of claim 1 wherein the look-up table supplies at least the first respective user-selected temperature to the PI controller via the second switching element when the measured temperature is less than about the first respective user-selected temperature, and the controller connecting the PI controller to the radiant heating element when the measured temperature is less than about the first respective user-selected temperature.

3. The apparatus of claim 1 wherein a predetermined maximum temperature is supplied to the PI controller when the measured temperature is greater than about the first respective user-selected temperature, and the controller being connected to the radiant heating element when the measured temperature is greater than about the first respective user-selected temperature.

4. The apparatus of claim 1 wherein a predetermined maximum temperature is supplied to the PI controller when the measured temperature is substantially equal to about the first respective user-selected temperature, and the controller being connected to the radiant heating element when the measured temperature is greater than about the first respective user-selected temperature.

5. The apparatus of claim 1 wherein the temperature sensor is positioned proximate to the cooktop.

6. The apparatus of claim 1 wherein the cooktop comprises a glass ceramic cooktop.

7. The apparatus of claim 6 wherein the temperature sensor is located inside the glass ceramic cooktop.

8. The apparatus of claim 1 wherein the first switching device comprises a software program receiving and selectively providing an output from the PI controller and the minimum selector output to the radiant heating element.

9. The apparatus of claim 1 wherein the second switching device comprises a software program receiving and selectively providing the output from the look-up table and a predetermined maximum temperature to the PI controller.

10. The apparatus of claim 1 wherein the look-up table comprises a software program comprising a list of the plurality of user power levels and the respective user-selected temperatures corresponding to each of the plurality of user power levels.

11. The apparatus of claim 1 wherein the look-up table comprises a database comprising a list of the plurality of user power levels and the respective user-selected temperatures corresponding to each of the plurality of user power levels.

12. The apparatus of claim 1 wherein the look-up table comprises an algorithm comprising a list of the plurality of user power levels and the respective user-selected temperatures corresponding to each of the plurality of user power levels.

13. The apparatus of claim 1 wherein the look-up table comprises a memory device comprising a list of the plurality of user power levels and the respective user-selected temperatures corresponding to each of the plurality of user power levels.

14. A method for rapidly heating a cooktop, the method comprising the steps of:

selecting a user power level using a user input device, the user power level corresponding to a respective user-selected temperature;

measuring a temperature of the cooktop using a temperature sensor;

comparing the measured temperature to the respective user-selected temperature;

supplying the respective user-selected temperature to a proportional-plus-integral (PI) controller of a fast heat-up circuit when the measured temperature is less than about the respective user-selected temperature;

connecting the PI controller to a radiant heating element when the measured temperature is less than about the respective user-selected temperature; and

applying a maximum power to the radiant heating element from the PI controller of the fast heat-up circuit for a predetermined amount of time when the measured temperature is less than about the respective user-selected temperature.

15. The method of claim 14 further comprising the steps of:

supplying a predetermined maximum temperature to the PI controller when the measured temperature is greater than about the respective user-selected temperature; and

connecting a controller to the radiant heating element when the measured temperature is greater than about the user selected temperature.

16. The method of claim 15 further comprising the steps of:

supplying a predetermined maximum temperature to the PI controller when the measured temperature is substantially equal to about the respective user-selected temperature; and

connecting the controller to the radiant heating element when the measured temperature is substantially equal to about the respective user-selected temperature.

17. A method for rapidly heating a cooktop, the method comprising the steps of:

selecting a user power level using a user input device, the user power level corresponding to a respective user-selected temperature;

measuring a temperature of the cooktop using a temperature sensor;

comparing the measured temperature to the respective user-selected temperature;

supplying the respective user-selected temperature to a proportional-plus-integral (PI) controller of a fast heat-up circuit when the measured temperature is less than about the respective user-selected temperature;

connecting the PI controller to the radiant heating element when the measured temperature is less than about the respective user-selected temperature;

supplying a predetermined maximum temperature to the PI controller when the measured temperature is greater than about the respective user-selected temperature;

connecting a controller to the radiant heating element when the measured temperature is greater than about the respective user-selected temperature;

supplying a predetermined maximum temperature to the PI controller when the measured temperature is substantially equal to about the respective user-selected temperature; and

connecting the controller to the radiant heating element when the measured temperature is substantially equal to about the respective user-selected temperature.

18. An apparatus for rapidly heating a cooktop, the apparatus comprising:

a radiant heating element positioned proximate to the cooktop;

a controller connected to the radiant heating element, the controller comprising;

a fast heat-up circuit selectively coupled to the radiant heating element, the fast heat-up circuit comprising;

a proportional-plus-integral (PI) controller selectively coupled to at least the look-up table;

a minimum selector having a minimum selector output, the minimum selector connected to the PI controller; and

an anti-wind up controller connected to the PI controller and the minimum selector output;

a look-up table selectively coupled to the fast heat-up circuit, the look-up table comprising a plurality of user power levels wherein each of the plurality of user power levels correlates to a respective user-selected temperature;

a user power input device connected to the controller and allowing selection of at least a first of the plurality of user power levels wherein the first power level corresponding to a first respective user selected temperature in the look-up table; and

a temperature sensor connected to the controller for measuring a temperature of the cooktop.

19. The apparatus of claim 18 further comprising:

a first switching device connected to the radiant heating element, the minimum selector output and PI controller;

a second switching device connected to the PI controller, the look-up table and a predetermined maximum temperature.

20. The apparatus of claim 19 wherein the first switching device comprises a software program receiving and selectively providing an output from the PI controller and the minimum selector output to the radiant heating element.

21. The apparatus of claim 19 wherein the second switching device comprises a software program receiving and selectively providing the output from the look-up table and a predetermined maximum temperature to the PI controller.

22. The apparatus of claim 18 wherein the look-up table comprises a software program comprising a list of the plurality of user power levels and the respective user-selected temperatures corresponding to each of the plurality of user power levels.

23. The apparatus of claim 18 wherein the look-up table comprises a database comprising a list of the plurality of user power levels and the respective user-selected temperatures corresponding to each of the plurality of user power levels.

24. The apparatus of claim 18 wherein the look-up table comprises an algorithm comprising a list of the plurality of user power levels and the respective user-selected temperatures corresponding to each of the plurality of user power levels.

25. The apparatus of claim 18 wherein the look-up table comprises a memory device comprising a list of the plurality of user power levels and the respective user-selected temperatures corresponding to each of the plurality of user power levels.