Electronic gas cooktop control with simmer system and method thereof

• US 7,255,100 B2
• Filed: 06/18/2001
• Issued: 08/14/2007
• Est. Priority Date: 10/18/1999
• Status: Expired due to Fees

• Current Assignee: Compuvalve LLC
• Original Assignee: Compuvalve LLC
• Inventors: Zhou, Feng, Shute, Suzanne J., Repper, Pierre P., Olson, Allen L., Shute, Christa B., Shute, Alan B.
• Primary Examiner(s): Price; Carl D.
• Application Number:
  US09/884,828
• Publication Number:
  US 20020045142A1
• Time in Patent Office: 2,248 Days
• Field of Search: 126/39.BA, 126/39.E, 431/12, 431/78, 431/262, 251/129.05, 251/129.08, 137/65, 137/66, 137/599.08
• US Class Current: 126/39.0BA
• CPC Class Codes: F23N 1/005 using electrical or electromechanical means F23N1/04 - F23N1/10 take precedence
• CPC Class Codes: F23N 2227/10 Sequential burner running
• CPC Class Codes: F23N 2227/36 Spark ignition, e.g. by means of a high voltage
• CPC Class Codes: F23N 2227/42 Ceramic glow ignition
• CPC Class Codes: F23N 2231/20 Warning devices
• CPC Class Codes: F23N 2231/22 using warning lamps
• CPC Class Codes: F23N 2235/16 variable flow or proportional valves
• CPC Class Codes: F23N 2237/02 two or more burners
• CPC Class Codes: F23N 2237/10 High or low fire
• CPC Class Codes: F23N 2241/08 Household apparatus
• CPC Class Codes: F23N 5/10 using thermocouples
• CPC Class Codes: F23N 5/203 using electronic means
• CPC Class Codes: F24C 3/126 on ranges
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2217/96066 Thumbwheel, potentiometer, scrollbar or slider simulation by touch switch
• CPC Class Codes: H03K 2217/960785 with illumination

Abstract

An electronically activated gas cooktop control system, responsive to a touch-sensitive user interface, and capable of providing a predetermined range of cooking and simmer levels of BTU output, has two complementary heating modes of operation A first heating mode of operation is provided to produce a wide selection of simmer levels of BTU output, by electronically sequencing a solenoid-operated modulating gas valve “on” and “off”, at a predetermined level of flame. A second cooking mode of operation is provided by electronically modulating the level of flame, through use of a pulse-width-modulation (PWM) output signal to produce a wide selection of cooking levels of BTU output. An igniter system capable of insuring proper ignition of gas without generating harmful electromagnetic interference is also provided.

Claims

1. A cooktop, comprising a gas burner, a dual function gas valve, a user interface, an electronic controller, an igniter, and a flame sensor, wherein said electronic controller is connected to said dual function gas valve to control gas flow to said gas burner, wherein said user interface is for user entry of burner heating level for said gas burner, wherein said electronic controller is operative to control said dual function gas valve in accordance with said user entry, wherein said flame sensor is connected and placed to monitor for presence of flames at said gas burner, wherein said dual function gas valve includes a first mechanism to operate in a first electronically controlled mode and a second mechanism to operate in a second electronically controlled mode, said first mode providing a continuous flame at said gas burner modulated to a predetermined lower first heating level or to a predetermined higher second heating level, and said second mode providing intermittent flame at said gas burner for producing heating levels less than said lower first heating level for simmering operation, said igniter connected to ensure reignition of the gas delivered to said gas burner when said dual function gas valve is operating in said second electronically controlled mode.

2. A cooktop as in claim 1, wherein said user interface comprises one or more touch-sensitive pads.

3. A cooktop as in claim 2, wherein said user interface further comprises a visual interface including a display selected from the list consisting of:

a) seven-segment LED displays;

b) discrete LED displays;

c) bar-graph LED displays;

d) LCD displays;

e) vacuum fluorescent displays; and

f) field-emission displays.

4. A cooktop as in claim 2, wherein said user interface further comprises an audible interface including an annunciator selected from the list consisting of:

a) an external drive piezo-acoustic element;

b) a built-in drive piezo-acoustic element;

c) an external drive magnetic transducer;

d) a built-in drive magnetic transducer;

e) an external drive speaker; and

f) a built-in drive speaker.

5. A cooktop as in claim 1, further comprising a plurality of gas burners, one said dual function gas valve for each said gas burner, wherein each of said gas valves includes a proportionally controlled solenoid-operated modulating gas valve, wherein no gas flows in its fully closed position.

6. A cooktop as in claim 5, wherein each of said dual function gas valves comprises a proportionally controlled solenoid-operated modulating gas valve wherein maximum gas flows in its fully open position.

7. A cooktop as in claim 6, wherein each of said dual function gas valves is also capable of providing any intermediate controlled position.

8. A cooktop as in claim 1, wherein said user interface comprises a multiplicity of touch-sensitive pads operable to select burner heating levels in a predetermined set of user-selectable steps.

9. A cooktop as in claim 8, wherein a lowest portion of said user-selectable steps corresponds to a flame “

on/off”

sequencing mode of flow settings of said dual function gas valve.

10. A cooktop as in claim 8, wherein a highest portion of said user-selectable steps corresponds to a continuous flame modulation mode of flow settings of said dual function gas valve.

11. A cooktop as in claim 8, wherein each of said user-selectable steps corresponds to one of a multiplicity of flow settings of said dual function gas valve in a predetermined range.

12. A cooktop as in claim 1, wherein said igniter comprises a resistive hot-surface igniter.

13. A cooktop, comprising:

a) a gas burner;

b) a dual function gas valve connected to control gas flow to said gas burner wherein said dual function gas valve includes a first mechanism to operate in a first electronically controlled mode and a second mechanism to operate in a second electronically controlled mode, said first mode providing a continuous flame at said gas burner modulated to a predetermined lower first heating level or to a higher second heating level, and said second mode providing intermittent flame at said gas burner for producing heating levels less than said lower first heating level for simmering operation;

c) a user interface for user entry of burner heating level for said gas burner, wherein said user interface comprises a multiplicity of touch-sensitive pads operable to select burner heating levels in a predetermined set of user-selectable steps and wherein a lowest portion of burner heating levels corresponds to a flame “

on/off”

sequencing mode of flow settings of said dual function gas valve;

d) a controller operative to control said dual function gas valve in accordance with said user entry;

e) an igniter connected to ensure reignition of the gas delivered to said gas burner when said dual function gas valve is operating in said second electronically controlled mode; and

f) a flame sensor connected and placed to monitor the presence of flames at said gas burner.

14. A cooktop as in claim 13, wherein said gas valve comprises a proportionally controlled solenoid-operated modulating gas valve wherein no gas flows in its fully closed position.

15. A cooktop as in claim 13, wherein said gas valve comprises a proportionally controlled solenoid-operated modulating gas, valve wherein maximum gas flows in its fully open position.

16. A cooktop as in either of claims 14 and 15, wherein said gas valve comprises a proportionally controlled solenoid-operated modulating gas valve is also capable of providing any intermediate controlled position.

17. A cooktop as in claim 13, wherein a highest portion of said user-selectable steps corresponds to a continuous flame modulation mode of flow settings of said dual function gas valve.

18. A cooktop as in claim 13, wherein each of said user-selectable steps corresponds to one of a multiplicity of flow settings of said dual function gas valve in a predetermined range.

19. A cooktop as in claim 13, wherein said user interface further comprises a visual interface including a display selected from the list consisting of:

a) seven-segment LED displays;

b) discrete LED displays;

c) bar-graph LED displays;

d) LCD displays;

e) vacuum fluorescent displays; and

f) field-emission displays.

20. A cooktop as in claim 13, wherein said user interface further comprises an audible interface including an annunciator selected from the list consisting of:

a) an external drive piezo-acoustic element;

b) a built-in drive piezo-acoustic element;

c) an external drive magnetic transducer;

d) a built-in drive magnetic transducer;

e) an external drive speaker; and

f) a built-in drive speaker.

21. A cooktop as in claim 13, wherein said igniter comprises a resistive hot-surface igniter.

22. A cooktop as in claim 13, further comprising a main in-line solenoid safety valve.

23. A heating device, comprising:

a gas burner;

a single dual function valve including both a first electronically controlled mechanism and a second electronically controlled mechanism within said single dual function valve, said single dual function valve connected to provide gas to said gas burner;

an electronic controller for electronically controlling said first electronicaily controlled mechanism and said second electronically controlled mechanism;

said first electronically controlled mechanism capable of providing at least two different on-levels of continuous gas flow to said gas burner; and

said second electronically controlled mechanism capable of stopping and starting flow of gas to said gas burner, wherein combination of said first electronically controlled mechanism and said second electronically controlled mechanism provides capability to achieve a lower temperature than is achievable with just continuous flow of gas from said first electronically controlled mechanism.

24. A heating device as recited in claim 23, wherein said first electronically controlled mechanism is capable of providing 30 different on-levels of gas flow.

25. A heating device as recited in claim 23, wherein said gas burner is capable of providing a flame, wherein said electronic controller is capable of controlling said second mechanism far sequencing the flame on and off at a predetermined level of flame.

26. A heating device as recited in claim 25, wherein said controller comprises a microcontroller, wherein sequencing the flame on and off is controlled by said microcontroller.

27. A heating device as recited in claim 26, wherein said microcontroller further comprises a pulse width modulation output port and an A/D converter.

28. A heating device as recited in claim 25, wherein sequencing the flame on and off is controlled by time.

29. A heating device as recited in claim 25, wherein sequencing the flame on and off is accomplished with the on level set to a predetermined medium level of flame or with the on level set to a medium-low level of BTU output.

30. A heating device as recited in claim 25, wherein sequencing the flame on and off is accomplished with gas flow on and off for time periods to correspond to a desired simmer level.

31. A heating device as recited in claim 23, wherein said controller uses pulse-width-modulation for controlling said first mechanism.

32. A heating device as recited in claim 23, further comprising an igniter, wherein said igniter assures re-ignition of said gas when said second mechanism is used.

33. A heating device as recited in claim 32, wherein said igniter does not need to be synchronized with on/off cycling of said flow of gas during simmer made.

34. A heating device as recited in claim 33, wherein said igniter is continuously powered when said second mechanism is used.

35. A heating device as recited in claim 32, wherein said igniter comprises a resistive hot-surface igniter.

36. A heating device as recited in claim 35, wherein said igniter comprises a ceramic hot-surface igniter capable of constant re-ignition.

37. A heating device as recited in claim 23, further comprising a main in-line solenoid safety valve.

38. A heating device as recited in claim 23, further comprising a plurality of gas burners and a plurality of said dual function valves, wherein each of said plurality of gas burners has one of said plurality of dual function valves connected to provide gas.

39. A heating device as recited in claim 23, wherein said first mechanism comprises a variable orifice solenoid that has a plurality of positions controlled by application of a voltage signal.

40. A heating device as recited in claim 23, further comprising an igniter for igniting gas when said first electronically controlled mechanism provides flow of gas.

41. A heating device as recited in claim 40, wherein said igniter is a hot-surface igniter.

42. A heating device as recited in claim 40, further comprising an igniter for igniting gas when said fist electronically controlled mechanism and said second electronically controlled mechanism provides flow of gas.

43. A beating device as recited in claim 42, wherein said igniter is set to be on continuously when said second electronically controlled mechanism is being used to stop and start flow of gas to said gas burner.

44. A heating device as recited in claim 40, further comprising a circuit to monitor ignition, said circuit including a sensor for sensing at least one from the group consisting of flame and current flowing in said igniter.

45. A heating device as recited in claim 23, further comprising a user interface.

46. A heating device as recited in claim 45, wherein said user interface comprises a dial control.

47. A heating device as recited in claim 45, wherein said user interface comprises touch switches.

48. A heating device as recited in claim 47, wherein said touch switches comprises a touch pad.

49. A heating device as recited in claim 45, wherein said user interface comprises a capacitive touch keyboard.

50. A heating device as recited in claim 45, wherein said user interface comprises a power key, an on key, power level control keys, and an off key.

51. A heating device as recited in claim 23, further comprising a digital visual display of cooking level of each said gas burner.

52. A heating device as recited in claim 51, wherein said digital visual display comprises an LED, LCD, or a vacuum fluorescent display.

53. A heating device as recited in claim 23, further comprising a burner base and a flame sensor fixed to said burner base.

54. A heating device as recited in claim 53, further comprising an igniter and a circuit to detect current flowing in said igniter, wherein if no current flows in said igniter during an ignition period or no flame is sensed then visual and audible alarms are generated.

55. A heating device as recited in claim 23, further comprising a main in-line valve for closing off flow if a fault condition occurs.

56. A heating device as recited in claim 55, further comprising an igniter, wherein said igniter is de-energized if a fault condition occurs.

57. A device for controlling flow of a fluid, comprising:

a dual function valve including both a first electronically controlled mechanism and a second electronically controlled mechanism;

an electronic controller for electronically controlling said first electronically controlled mechanism and said second electronically controlled mechanism;

said first electronically controlled mechanism capable of providing at least two different on-levels of continuous fluid flow; and

said second electronically controlled mechanism capable of continuously being sequenced between allowing fluid flow on and sealed off to prevent fluid flow thereby providing an intermittent flow of fluid, wherein said second electronically controlled mechanism is set to allow flow for a fraction of time and is otherwise set to be sealed off, wherein overall flow is proportional to said fraction.

58. A device as recited in claim 57, wherein said fluid comprises gas.

59. A device as recited in claim 58, wherein said first electronically controlled mechanism is capable of providing any intermediate level of gas flow.

60. A device as recited in claim 58, wherein said first electronically controlled mechanism is capable of providing 30 different on-levels of gas flow.

61. A device as recited in claim 58, wherein said electronic controller is capable of controlling said second mechanism for sequencing flow on and off at a predetermined level.

62. A device as recited in claim 61, wherein said controller comprises a microcontroller, wherein sequencing fluid flow on and off is controlled by said microcontroller.

63. A device as recited in claim 62, wherein said microcontroller further comprises a pulse width modulation output port and an A/D converter.

64. A device as recited in claim 61, wherein sequencing the flow on and off is controlled by time.

65. A device as recited in claim 61, wherein sequencing the flow on and off is accomplished with the on level set to a medium-low level.

66. A device as recited in claim 61, wherein sequencing the flow on and off is accomplished with gas flow on for 1 second and off for 8 seconds.

67. A device as recited in claim 57, further comprising a digital visual display of flow.

68. A device as recited in claim 67, wherein said digital visual display comprises an LED, LCD, or a vacuum fluorescent display.

69. A device as recited in claim 57, wherein said controller uses pulse-width-modulation for controlling said first mechanism.

70. A device as recited in claim 57, further comprising a main in-line solenoid safety valve.

71. A device as recited in claim 57, wherein said first mechanism comprises a variable orifice solenoid that has a plurality of positions controlled by application of a voltage signal.

72. A device as recited in claim 57, wherein said fluid comprises gas and wherein a single gas valve includes both said first electronically controlled mechanism and said second electronically controlled mechanism.

73. A device as recited in claim 57, further comprising a user interface.

74. A device as recited in claim 73, wherein said user interface comprises a dial control.

75. A device as recited in claim 73, wherein said user interface comprises touch switches.

76. A device as recited in claim 75, wherein said touch switches comprises a touch pad.

77. A device as recited in claim 73, wherein said user interface comprises a capacitive touch keyboard.

78. A device as recited in claim 73, wherein said user interface comprises a power key, an on key, power level control keys, and an off key.