Systems and methods of using multiple microcontrollers for fail-safe control and enhanced feature operation of an appliance

• US 7,069,109 B2
• Filed: 11/09/2004
• Issued: 06/27/2006
• Est. Priority Date: 11/09/2004
• Status: Active Grant

• Current Assignee: EGO Elektro-Gerã¤Tebau GmbH (EGO Blanc und Fischer & Company GmbH)
• Original Assignee: E.G.O. North America Inc. (Blanc & Fischer Familienholding GmbH)
• Inventors: Huffington, Jeff
• Primary Examiner(s): PATEL, RAMESH B
• Application Number:
  US10/985,107
• Publication Number:
  US 20060100718A1
• Time in Patent Office: 595 Days
• Field of Search: 700/1, 700/19, 700/20, 700/21, 700/23, 700/17, 700/83, 700/207, 700/211, 219/391, 219/413, 219/414, 126/19, 126/20, 126/21, 126/22, 126/39, 236/46
• US Class Current: 700/211
• CPC Class Codes: G05B 9/03 with multiple-channel loop, i.e. redundant control systems

Abstract

Multiple microcontrollers are used in controlling operation of an appliance thereby providing enhanced safety. User input deactivating the appliance is received and processed by a first and second microcontrollers, which separately and independently act to remove power from the appliance upon receipt of user input. Failure of one microcontroller in processing user input does not result in the appliance entering into an unsafe mode. Further, a third processor in a power supply module is used to control power into, and out of, the power supply module, so that under certain conditions, power may be remove from the system entirely or to certain components.

Claims

1. A system for controlling a kitchen cooking appliance comprising:

a first microcontroller executing a first program, the first microcontroller receiving a user input signal for controlling operation of the kitchen cooking appliance, the first microcontroller providing a first power control signal to vary the amount of power provided to a heating element in the kitchen cooking appliance;

a second microcontroller executing a second program, the second microcontroller receiving the user input signal, the second microcontroller providing a control signal;

a power generator module receiving the first power control signal from the first microcontroller and providing the power over a circuit to the heating element, the amount of the power provided to the heating element determined by the first power control signal; and

a switching element receiving the power control signal from the second processor capable of interrupting the circuit providing the power to the heating element.

2. The system of claim 1 wherein the switching element is a transistor.

3. The system of claim 1 wherein the switching element in a relay.

4. The system of claim 1 wherein the first power control signal is a square wave having a periodic frequency.

5. The system of claim 1 wherein the power provided to the heating element is based on a nominal household voltage of either 120 volts or 240 volts.

6. The system of claim 1 wherein the control signal has two voltage levels, wherein one level causes the interruption of the circuit providing the power to the heating element.

7. A system for controlling an appliance comprising:

a function controller module comprising;

a first microcontroller executing a first program, the first microcontroller receiving a user input for controlling operation of the appliance, the first microcontroller providing a first power control signal to vary the amount of power provided to a heat generating component in the appliance; and

a second microcontroller executing a second program, the second microcontroller receiving a status input signal associated with the status of the appliance, the second microcontroller providing a fail-safe control signal in response to the status input signal;

a power generator module receiving the first power control signal from the first microcontroller and providing in response a second power control signal to vary the amount of power provided to the heat generating component; and

a switch receiving the fail-safe control signal from the second processor and interrupting a circuit conveying the second power control signal.

8. The system of claim 7 wherein the status input signal is associated with detecting a voltage level.

9. The system of claim 7 wherein the status input signal is associated with detecting a current level.

10. The system of claim 7 wherein the status input signal is associated with detecting a temperature level.

11. The system of claim 10 wherein the temperature level is associated with the heat generating component.

12. The system of claim 10 wherein the temperature level is associated with an oven.

13. The system of claim 7 wherein the fail-safe control signal removes power provided to the heat generating component in the appliance.

14. The system of claim 13 wherein the fail-safe control signal has one of two operating voltages.

15. The system of claim 7 wherein the first program is written using a different microcontroller instruction set than the second program.

16. A system for controlling an appliance comprising:

a function controller module comprising;

a first microcontroller executing a first program receiving a user input directed to the control of the appliance, the first microcontroller providing a first power control signal to vary the amount of power provided to a heating generating component in the appliance; and

a second microcontroller executing a second program, also receiving the user input directed to the control of the appliance, the second microcontroller providing a control signal;

a power generator module receiving the first power control signal from the first microcontroller and providing in response a second power control signal to vary the amount of power provided to the heat generating component; and

a switching means receiving the control signal from the second processor and interrupting a circuit conveying the second power control signal.

17. The system of claim 16 further comprising

a display operatively controlled by the first microcontroller presenting data to a user regarding the amount of power provided to the heat generating component.

18. The system of claim 16 further comprising a keypad for the user to provide input regarding a desired level of power provided to the heat generating component.

19. The system of claim 16 wherein the first power control signal comprises LIN-based protocol messages.

20. The system of claim 19 wherein the second power control signals comprises a modulated signal.

21. The system of claim 16 wherein the switching means comprises a relay.

22. The system of claim 16 wherein the switching means comprises a transistor.

23. The system of claim 16 wherein the switching means comprises an opto-isolator.

24. The system of claim 16 wherein the heat generating component is one from the group comprising an induction element, radiant heat coil, and resistance heating element.

25. The system of claim 16 wherein the power supply module incorporates a switching power supply.

26. The system of claim 16 further comprising an opto-isolator disposed between the second microcontroller and the power supply module to provide opto-isolation of the signal from the second microcontroller to the power supply module.

27. The system of claim 16 further comprising a relay disposed between the second microcontroller and the power supply module to transfer the second power control signal.

28. The system of claim 16 wherein the second microcontroller generates the control signal thereby completing the circuit conveying the second power control signal.

29. The system of claim 16 wherein the second microcontroller generates the control signal thereby interrupting the circuit conveying the second power control signal.

30. The system of claim 16 wherein the first program is a software routine comprising a program that is different from the second program.

31. A method of operating an appliance comprising the steps of:

receiving an input signal from an input device of a household cooking appliance at a first microcontroller executing a first control program, the input signal indicating a change in the operation of a heating element in the appliance;

generating a first power control signal from the first microcontroller, the first signal controlling the amount of power provided to the heating element;

receiving the input signal at a second microcontroller executing a second control program;

generating a control signal at the second microcontroller, the control signal controlling a circuit conveying the first power control signal; and

interrupting the circuit conveying the first power control signal thereby removing power to the heating element.

32. The method of claim 31 wherein the first power control signal actuates a relay controlling the circuit conveying the first power control signal.

33. The method of claim 32 wherein the user input signal indicates deactivation of the heating element and the actuating of the relay comprises interrupting the circuit.

34. The method of claim 31 wherein the first power control signal is a time varying periodic signal.

35. The method of claim 31 wherein the second microcontroller ascertains the status of the first microcontroller prior to generating the control signal.

36. A method for operating an appliance comprising the steps of:

generating an input signal in response to a user action indicating a change of the operation of a heat generating component in the appliance;

receiving the input signal at a first microcontroller executing a first program, the first microcontroller generating a first power control signal conveying one of a plurality of values associated with a plurality of heating levels associated with the heat generating component of the appliance;

receiving the first power control signal at a power control module wherein the power control module generates a second power control signal;

receiving the input signal at a second microcontroller, the second microcontroller executing a second program;

generating at the second microcontroller a control signal controlling the switching a circuit conveying the power control signal; and

the power control module altering the heating level associated with the heat generating component in the appliance in response to the first power control signal.

37. The method of claim 36 wherein the first power control signal controlling the operation of the appliance is further associated with one of a plurality of heat generating components.

38. The method of claim 36 wherein the control signal controlling the switching a circuit interrupts the circuit conveying the second power control signal to be interrupted.

39. The method of claim 38 wherein the control signal is generated in response to the input signal indicating a deactivation of the heat generating component.

40. The method of claim 38 wherein the control signal is generated in response to a temperature signal.

41. The method of claim 40 wherein the temperature signal indicates an unsafe condition of the appliance.

42. The method of claim 36 wherein the second microcontroller queries the first microcontroller prior to generating the control signal.

43. The method of claim 42 wherein the second microcontroller generates the control signal in response to the status of first microcontroller.

44. A method for operating an appliance comprising the steps of:

generating an input signal in response indicating a change in the operation of a heat generating component in an appliance;

receiving the input signal at a first microcontroller executing a first program, the first microcontroller generating a first message controlling the operation of the appliance;

receiving the input at a second microcontroller, the second microcontroller executing a second program;

generating at the second microcontroller a control signal switching a circuit conveying a power control signal; and

altering the operation of the heat generating component in the appliance in response to the power control signal.

45. The method of claim 44 further comprising the steps of:

receiving the first message at a third microcontroller associated with a power control module;

selecting one of two heat generating components controlled by the power control module, the selection based on the contents of the first message;

determining the power output control signal of the third microcontroller; and

providing the power output control signal to the selected heat generating component.

46. A method for operating of an appliance comprising the steps of:

generating an input signal in response to a user action indicating a change in operation of a heat generating component in an appliance;

receiving the input signal at a first microcontroller executing a first program, the first microcontroller generating a first signal controlling the operation of the appliance;

receiving a status input signal at a second microcontroller, the second microcontroller executing a second program;

generating at the second microcontroller a second signal controlling a switching device controlling a circuit conveying a power control signal;

receiving the first signal at a power module wherein the power module generates the power control signal;

the power module altering the operation of the heat generating component in the appliance in response to the power control signal; and

the second microcontroller altering the second signal based on the input signal, the second signal causing the switching device to interrupt the circuit conveying the power control signal.

47. The method of claim 46 wherein the input from the user indicates the heat generation component is to be deactivated and the second microcontroller generates in response the second signal.