System and method for controlling a dryer appliance

• US 20040200093A1
• Filed: 04/23/2004
• Published: 10/14/2004
• Est. Priority Date: 05/02/2000
• Status: Active Grant

• Current Assignee: Haier US Appliance Solutions, Inc. DBA GE Appliances (Haier Group Company)
• Original Assignee: Alexander Carswell Cambon, Cathy Diane Emery, Mahmoud Fariz Ismail, Michel Dion, William Joseph Wunderlin, Zubair Hameed
• Inventors: Dion, Michel, Hameed, Zubair, Emery, Cathy Diane, Cambon, Alexander Carswell, Wunderlin, William Joseph, Ismail, Mahmoud Fariz
• Granted Patent: US 7,013,578 B2
• Time in Patent Office: Days
• US Class Current: 34/606
• CPC Class Codes: D06F 2101/00 User input for the control of domestic laundry washing machines, washer-dryers or laundry dryers
• CPC Class Codes: D06F 2103/10 expressed as capacitance or resistance
• CPC Class Codes: D06F 2103/38 Time, e.g. duration
• CPC Class Codes: D06F 2103/44 Current or voltage
• CPC Class Codes: D06F 2105/28 Electric heating
• CPC Class Codes: D06F 2105/46 Drum speed; Actuation of motors, e.g. starting or interrupting
• CPC Class Codes: D06F 2105/52 Changing sequence of operational steps; Carrying out additional operational steps; Modifying operational steps, e.g. by extending duration of steps
• CPC Class Codes: D06F 2105/56 Remaining operation time; Remaining operational cycles
• CPC Class Codes: D06F 2105/58 Indications or alarms to the control system or to the user
• CPC Class Codes: D06F 2105/60 Audible signals
• CPC Class Codes: D06F 34/08 Control circuits or arrangements thereof
• CPC Class Codes: D06F 58/38 of drying, e.g. to achieve the target humidity
• CPC Class Codes: D06F 58/46 Control of the operating time

Abstract

System and method for controlling an appliance for drying clothing articles is provided. The appliance has a container for receiving the clothing articles. A motor is provided for rotating the container about an axis. A heater is provided for supplying heated air to the container during a dry cycle. A sensor is provided for providing a signal indicative of moisture content of the articles. Memory is provided memory for storing historical stop time data of respective dry cycles. A noise-reduction filter is coupled to receive the signal from the moisture sensor to provide selectable filtering to that signal. A timer provides a signal indicative of elapsed time upon start of the dry cycle. A module is responsive to the historical data in the memory for determining an initial estimate of the stop time of the dry cycle to be executed. A processor allows for estimating the stop time of the dry cycle as the cycle is being executed. The estimation of the stop time is based on a respective functional relationship of the noise-reduced sensor signal, and the timer signal, relative to one or more characteristics of the articles and one or more desired values of predetermined dry-cycle parameters selectable by a respective user of the dryer. The initial estimate of the stop time is superceded by the stop time estimated by the processor as the cycle is being executed.

Claims

1. An appliance for drying clothing articles, the appliance comprising:

a container for receiving the clothing articles;

a motor for rotating the container about an axis;

a heater for supplying heated air to the container during a dry cycle;

a sensor for providing a signal indicative of moisture content of the articles;

memory for storing historical stop time data of respective dry cycles;

a noise-reduction filter coupled to receive the signal from the moisture sensor to provide selectable filtering to that signal;

a timer for providing a signal indicative of elapsed time upon start of the dry cycle;

a module responsive to the historical data in the memory for determining an initial estimate of the stop time of the dry cycle to be executed; and

a processor for estimating the stop time of the dry cycle as the cycle is being executed, the estimation of the stop time based on a respective functional relationship of the noise-reduced sensor signal, and the timer signal, relative to one or more characteristics of the articles and one or more desired values of predetermined dry-cycle parameters selectable by a respective user of the dryer, the initial estimate of the stop time being superceded by the stop time estimated by the processor as the cycle is being executed.

2. The appliance of claim 1 further comprising a control decision module coupled to the processor to receive the stop time being estimated therein for controlling the appliance subsequent to the dry cycle.

3. The appliance of claim 2 wherein the control decision module is further configured for controlling execution of a sanitize cycle subsequent to the dry cycle.

4. The appliance of claim 1 wherein the memory further stores summary statistics of the historical data.

5. An appliance for drying clothing articles, the appliance comprising:

a container for receiving the clothing articles;

a motor for rotating the container about an axis;

a heater for supplying heated air to the container during a dry cycle to be executed; and

a module for estimating an initial stop time of the dry cycle to be executed based on historical stop time data of previously executed dry cycles.

6. The appliance of claim 5 wherein the module for estimating the initial stop time is configured to execute a moving average of the historical stop time data.

7. The appliance of claim 6 wherein the moving average executed on the historical data is an exponentially-weighted moving average.

8. The appliance of claim 5 further comprising a sub-module for maintaining consistent relationships for each estimated initial stop time regardless of respective characteristics of the articles and desired values of respective dry-cycle parameters selectable by a respective user of the dryer.

9. The appliance of claim 8 wherein the sub-module is configured to execute the following:

constructing a table having a plurality of cells respectively populated with initial stop time estimates corresponding to the respective characteristics of the articles and desired values of the dry-cycle parameters;

selecting one of the plurality of cells as a reference cell;

retrieving the last value of the reference cell;

retrieving an estimated stop time value of the last-executed dry cycle;

retrieving the actual stop time value of the last-executed dry cycle; and

calculating a present value of the reference cell based on executing a predetermined moving average on the respective retrieved values.

10. The appliance of claim 9 wherein the sub-module is further configured to execute the following:

updating each initial stop time estimate in each cell, other than the reference cell, based on a respective weighing ratio relative to the calculated present value of the reference cell.

11. An appliance for drying clothing articles, the appliance comprising:

a container for receiving the clothing articles;

a motor for rotating the container about an axis;

a heater for supplying heated air to the container during a dry cycle;

a sensor for providing a signal indicative of moisture content of the articles;

a noise-reduction filter coupled to receive the signal from the moisture sensor to provide selectable filtering to that signal, the noise-reduction filter configured to detect changes in the level of the signal and/or in the slope of the received signal to execute the selectable filtering.

12. The appliance of claim 11 wherein the noise-reduction filter comprises a Holt'"'"'s linear filter.

13. The appliance of claim 11 wherein the noise-reduction filter is selected from the group consisting of a Holt'"'"'s linear filter, a median polish filter, a locally-weighted sum of squares filter, a resistant smoothing filter and a spline fit filter.

14. The appliance of claim 12 wherein the Holt'"'"'s linear filter has first and second smoothing constants having respective values selected based on a rate for sampling the sensor signal.

15. The appliance of claim 14 wherein the respective values of the first and second smoothing constants are further based on the expected noise characteristics of the sensor signal.

16. The appliance of claim 11 further comprising a single exponential smoothing filter having an adjustable smoothing constant having a first value when the level of the sensor signal being smoothed is increasing and having a second value being smaller relative to the first value when the level of the sensor signal is decreasing.

17. An appliance for drying clothing articles, the appliance comprising:

a container for receiving the clothing articles;

motor for rotating the container about an axis;

a heater for supplying heated air to the container during a dry cycle;

a sensor for providing a signal indicative of moisture content of the articles;

a timer for providing a signal indicative of elapsed time upon start of the dry cycle;

a processor for estimating the stop time of a respective dry cycle as the cycle is being executed, the estimation of the stop time based on a respective functional relationship of the sensor signal, and the timer signal, relative to one or more characteristics of the articles and one or more desired values of predetermined dry-cycle parameters selectable by a respective user of the dryer.

18. The appliance of claim 17 wherein the stop time estimated by the processor is bounded between a lower minimum time and a maximum time for executing the dry cycle, each respective lower and maximum time being chosen based on the one or more characteristics of the articles and the one or more desired values of the dry-cycle parameters.

19. The appliance of claim 17 wherein the processor is responsive to selection signals supplied thereto indicative of the fabric type of the articles to be dried and/or the heating level to be applied during the respective dry cycle to select the respective functional relationship to be executed to estimate the stop time.

20. The appliance of claim 17 wherein the processor includes a module for estimating the stop time even if the sensor signal approaches a region having a relatively flat response to further changes in the moisture content of the articles.

21. The appliance of claim 20 wherein the module for estimating the stop time notwithstanding of the flat response of the sensor signal is configured to execute the following:

receiving an estimate of the time required to reach a first level of moisture content in the articles for a respective article fabric based on a respective functional relationship of the sensor and timer signal relative to that fabric; and

estimating the time to reach a second level of moisture content in the articles for the respective fabric, the second level of moisture content being lower relative to the first level of moisture content and corresponding to a sensor signal in the region having a relatively flat signal response, the time for reaching the second level being estimated based on adding a predetermined percentage of the time required to reach the first level.

22. The appliance of claim 17 wherein the predetermined functional relationship of the sensor signal, and the timer signal, for determining the stop time relative to the predetermined characteristics of the articles and the desired values of the dry-cycle parameters comprises a continuous relationship.

23. The appliance of claim 17 wherein the processor includes a module for estimating the stop time to achieve a desired level of moisture content while adjusting for moisture loss or gain during a cool-down cycle.

24. The appliance of claim 23 wherein the moisture loss or gain is based on the moisture content in the articles prior to execution of the cool-down cycle.

25. An appliance for drying clothing articles, the appliance comprising:

a container for receiving the clothing articles;

a motor for rotating the container about an axis;

a heater for supplying heated air to the container during a dry cycle;

a sensor for providing a signal indicative of moisture content of the articles;

memory for storing historical stop time data of respective dry cycles;

a timer for providing a signal indicative of elapsed time upon start of the dry cycle;

a module responsive to the historical data in the memory for determining an initial estimate of the stop time of the dry cycle to be executed;

a processor for estimating the stop time of a respective dry cycle as the cycle is being executed, the estimation of the stop time based on a respective functional relationship of the noise-reduced sensor signal, and the timer signal, relative to one or more characteristics of the articles and one or more desired values of dry-cycle parameters selectable by a respective user of the dryer; and

a stop time update module configured to update the estimated initial stop time as the dry cycle is being executed based on the stop time estimation from the processor.

26. The appliance of claim 25 further comprising a display for displaying data related to the stop time estimate for the dry cycle.

27. The appliance of claim 26 wherein the display comprises a light-emitting diode display.

28. The appliance of claim 26 wherein the display comprises a liquid crystal display.

29. The appliance of claim 26 wherein the display in response to respective control signals applied thereto is configured to execute the following:

displaying the initial estimate of the stop time;

counting down to a minimum stop time for the cycle being executed;

displaying the stop time estimate from the processor upon a respective moisture threshold level being reached; and

displaying an await indication in case the threshold level has not being reached.

30. The appliance of claim 29 wherein the display comprises a plurality of segments being selectively lighted in response to the control signals.

31. The appliance of claim 29 wherein the control signals applied to the display are programmed for sequentially illuminating adjacent segments at the periphery of the display at a predetermined rate to give the appearance of movement around the periphery of the display and thus conveying to the user the await indication.

32. The appliance of claim 29 wherein the predetermined rate is chosen proportional to the time remaining for completing the dry cycle being executed.

33. The appliance of claim 26 wherein the stop time update module is configured to update the stop time being presently displayed without substantial time jumps through the use of await indications in case the estimated stop time by the processor is longer relative to the presently displayed stop time.

34. The appliance of claim 33 wherein the display comprises a plurality of segments being selectively lighted in response to control signals applied thereto.

35. The appliance of claim 34 wherein the control signals applied to the display are programmed for sequentially illuminating adjacent segments at the periphery of the display at a predetermined rate to give the appearance of movement around the periphery of the display and thus conveying to the user the await indication.

36. The appliance of claim 35 wherein the predetermined rate is chosen proportional to the time remaining for completing the dry cycle being executed.

37. An appliance for drying clothing articles, the appliance comprising:

a container for receiving the clothing articles;

a motor for rotating the container about an axis;

a heater for supplying heated air to the container during a dry cycle;

a sensor for providing a signal indicative of moisture content of the articles;

a timer for providing a signal indicative of elapsed time upon start of the dry cycle;

a processor for estimating the stop time of a respective dry cycle as the cycle is being executed, the estimation based on a respective functional relationship of the sensor signal, and the timer signal, relative to one or more characteristics of the articles and one or more desired values of predetermined dry-cycle parameters selectable by a respective user of the dryer; and

a control decision module coupled to the processor to receive the stop time being estimated therein for controlling the appliance subsequent to the dry cycle, the control decision module being configured for controlling execution of a sanitize cycle subsequent to the dry cycle by energizing the heater to supply heated air at a respective heat level for a respective period of time upon execution of the dry cycle.

38. The appliance of claim 37 wherein the respective period of time for executing the sanitize cycle is selected based on the stop time estimation from the processor.

39. The appliance of claim 38 wherein the respective heat level and period of time is selected to substantially reduce any microorganisms likely to be encountered in the articles upon execution of the dry cycle.

40. The appliance of claim 37 wherein the control decision module is responsive to a single actuation by the user of a sanitize selection key for selecting said sanitize cycle.

41. The appliance of claim 37 wherein the control decision module has a sub-module for preventing selection of the sanitize cycle depending on the article fabric selected by the user.

42. The appliance of claim 41 comprising a stop time update module configured to update the stop time estimation from the processor based on any additional time required for executing the sanitize cycle.

43. The appliance of claim 42 further comprising a display for displaying data related to the stop time estimate for the dry cycle and the sanitize cycle.

44. A method for drying clothing articles in a dryer appliance, the method comprising:

generating a signal indicative of moisture content of the articles;

storing historical stop time data of respective dry cycles;

executing selectable filtering to the sensor signal to generate a smoothed signal;

generating a signal indicative of elapsed time upon start of the dry cycle;

determining an initial estimate of the stop time of the dry cycle to be executed based on the historical stop time data; and

estimating the stop time of the dry cycle as the cycle is being executed, the estimation of the stop time based on a respective functional relationship of the noise-reduced signal, and the elapsed time signal, relative to one or more characteristics of the articles and one or more desired values of predetermined dry-cycle parameters selectable by a respective user of the dryer, the initial estimate of the stop time being superceded by the stop time estimated as the cycle is being executed.

45. The method of claim 44 further comprising processing the stop time estimated as the cycle is being executed for controlling the appliance subsequent to the dry cycle.

46. The method of claim 45 further comprising controlling execution of a sanitize cycle subsequent to the dry cycle.

47. The method of claim 44 wherein the storing step comprises storing summary statistics of the historical data.

48. A method for drying clothing articles in a dryer appliance, the method comprising estimating an initial stop time of the dry cycle to be executed based on historical stop time data of previously executed dry cycles.

49. The method of claim 48 wherein estimating the initial stop time comprises executing a moving average on the historical stop time data.

50. The method of claim 49 wherein the moving average executed on the historical data is an exponentially-weighted moving average.

51. The method of claim 48 further comprising maintaining consistent relationships for each estimated initial stop time regardless of respective characteristics of the articles and desired values of respective dry-cycle parameters selectable by a respective user of the dryer.

52. The method of claim 51 wherein maintaining consistent relationships comprises:

constructing a table having a plurality of cells respectively populated with initial stop time estimates corresponding to the respective characteristics of the articles and desired values of the dry-cycle parameters;

selecting one of the plurality of cells as a reference cell;

retrieving the last value of the reference cell;

retrieving an estimated stop time value of the last-executed dry cycle;

retrieving the actual stop time value of the last-executed dry cycle; and

calculating a present value of the reference cell based on executing a predetermined moving average on the respective retrieved values.

53. The method of claim 52 further comprising updating each initial stop time estimate in each cell, other than the reference cell, based on a respective weighing ratio relative to the calculated present value of the reference cell.

54. A method for drying clothing articles in a dryer appliance, the method comprising:

generating a signal indicative of moisture content of the articles;

executing a filtering technique on the generated signal to reduce the level of noise therein, the filtering technique selected to detect changes in the level of the signal and/or in the slope of the generated signal.

55. The method of claim 54 wherein the filtering technique comprises a Holt'"'"'s linear filtering technique.

56. The method of claim 54 wherein the filtering technique is selected from the group consisting of a Holt'"'"'s linear filtering technique, a median polish filtering technique, a locally-weighted sum of squares filtering technique, a resistant smoothing filtering technique and a spline fit filtering technique.

57. The method of claim 55 wherein the Holt'"'"'s linear filtering has first and second smoothing constants having respective values selected based on a rate for sampling the sensor signal.

58. The method of claim 57 wherein the respective values of the first and second smoothing constants are further based on the expected noise characteristics of the sensor signal.

59. The method of claim 54 further comprising a single exponential smoothing filtering having an adjustable smoothing constant having a first value when the level of the signal being smoothed is increasing and having a second value being smaller relative to the first value when the level of the signal is decreasing.

60. A method for drying clothing articles in a dryer appliance, the method comprising:

generating a signal indicative of moisture content of the articles;

generating a signal indicative of elapsed time upon start of the dry cycle;

estimating the stop time of a respective dry cycle as the cycle is being executed, the estimation of the stop time based on a respective functional relationship of the moisture-indicative signal, and the elapsed-time signal, relative to one or more characteristics of the articles and one or more desired values of predetermined dry-cycle parameters selectable by a respective user of the dryer.

61. The method of claim 60 wherein the estimated stop time is bounded between a lower minimum time and a maximum time for executing the dry cycle, each respective lower and maximum time being chosen based on the one or more characteristics of the articles and the one or more desired values of the dry-cycle parameters.

62. The method of claim 60 further comprising supplying selection signals indicative of the fabric type of the articles to be dried and/or the heating level to be applied during the respective dry cycle to select the respective functional relationship to be executed to estimate the stop time.

63. The method of claim 60 further comprising estimating the stop time even if the moisture-indicative signal approaches a region having a relatively flat response to further changes in the moisture content of the articles.

68. A method for drying clothing articles in a dryer appliance, the method comprising:

generating a signal indicative of moisture content of the articles;

storing historical stop time data of respective dry cycles;

generating a signal indicative of elapsed time upon start of the dry cycle;

processing the historical data for determining an initial estimate of the stop time of the dry cycle to be executed;

estimating the stop time of a respective dry cycle as the cycle is being executed, the estimation of the stop time based on a respective functional relationship of the moisture-indicative signal, and the time-elapsed signal, relative to one or more characteristics of the articles and one or more desired values of dry-cycle parameters selectable by a respective user of the dryer; and

updating the estimated initial stop time as the dry cycle is being executed based on the stop time estimation as the cycle is being executed.

69. The method of claim 68 further comprising displaying data related to the stop time estimate for the dry cycle.

70. The method of claim 69 wherein the displaying comprises:

displaying the initial estimate of the stop time in a display;

counting down to a minimum stop time for the cycle being executed;

displaying the stop time estimate from the processor upon a respective moisture threshold level being reached; and

displaying an await indication in case the threshold level has not being reached.

71. The method of claim 70 further comprising selectively lighting a plurality of display segments in response to control signals applied thereto.

72. The method of claim 70 wherein the control signals are programmed for sequentially illuminating adjacent segments at the periphery of the display at a predetermined rate to give the appearance of movement around the periphery of the display and thus conveying to the user an await indication.

73. The method of claim 72 wherein the predetermined rate is chosen proportional to the time remaining for completing the dry cycle being executed.

74. The method of claim 70 wherein the updating of the stop time being presently displayed is executed without substantial time jumps through the use of await indications in case the estimated stop time is longer relative to the presently displayed stop time.

75. The method of claim 74 further comprising selectively lighting a plurality of display segments in response to control signals applied thereto.

76. The method of claim 75 wherein the control signals applied to the display are programmed for sequentially illuminating adjacent segments at the periphery of the display at a predetermined rate to give the appearance of movement around the periphery of the display and thus conveying to the user the await indication.

77. The method of claim 76 wherein the predetermined rate is chosen proportional to the time remaining for completing the dry cycle being executed.

78. A method for drying clothing articles in a dryer appliance, the method comprising:

generating a signal indicative of moisture content of the articles;

generating a signal indicative of elapsed time upon start of the dry cycle;

estimating the stop time of a respective dry cycle as the cycle is being executed, the estimation of the stop time based on a respective functional relationship of the moisture-indicative signal, and the time-elapsed signal, relative to one or more characteristics of the articles and one or more desired values of predetermined dry-cycle parameters selectable by a respective user of the dryer; and

controlling the appliance subsequent to the dry cycle to execute a sanitize cycle by energizing a heater to supply heated air at a respective heat level for a respective period of time upon execution of the dry cycle.

79. The method of claim 78 wherein the respective period of time for executing the sanitize cycle is selected based on the estimated stop time.

80. The method of claim 79 wherein the respective heat level and period of time is selected to substantially reduce any microorganisms likely to be encountered in the articles upon execution of the dry cycle.

81. The method of claim 78 further comprising a single actuation by the user of a sanitize selection key for selecting said sanitize cycle.

82. The method of claim 78 further comprising preventing selection of the sanitize cycle depending on the article fabric selected by the user.

83. The method of claim 82 further comprising updating the stop time estimation from the processor based on any additional time required for executing the sanitize cycle.

84. The method of claim 83 further comprising displaying data related to the stop time estimate for the dry cycle and the sanitize cycle.

85-125. -125. (canceled)