Dryer appliances and methods for operating same

Dryer appliances and methods for operating dryer appliances are provided. A method includes calculating an initial cycle time, and counting down from the initial cycle time for an initial countdown time. The method further includes determining, during the step of counting down from the initial cycle time for the initial countdown time, whether a load size value and an air flow value have been established. The method further includes calculating, when the load size value and the air flow value have been established, a first updated remaining cycle time based on the load size value and the air flow value.

FIELD OF THE INVENTION

The present subject matter relates generally to dryer appliances and associated methods for operating dryer appliances.

BACKGROUND OF THE INVENTION

Dryer appliances generally include a cabinet with a drum mounted therein. In many dryer appliances, a motor rotates the drum during operation of the dryer appliance, e.g., to tumble articles located within a chamber defined by the drum. Alternatively, dryer appliances with fixed drums have been utilized. Dryer appliances also generally include a heater assembly that passes heated air through the chamber of the drum in order to dry moisture-laden articles disposed within the chamber. This internal air then passes from the chamber through a vent duct to an exhaust conduit, through which the air is exhausted from the dryer appliance. Typically, a blower is utilized to flow the internal air from the vent duct to the exhaust duct. When operating the blower may pull air through itself from the vent duct, and this air may then flow from the blower to the exhaust conduit.

One issue that exists with dryer appliances is the predictability of the drying time for a load of articles being dried. It is generally understood that drying time is a function of, for example, the desired cycle, the desired amount of heat, and the desired dryness. One presently known solution for predicting drying time based on such variables during operation of a dryer appliance is provided in U.S. Patent Application Publication No. 2006/0191161, filed on Jan. 20, 2006 and published on Aug. 31, 2006, which is incorporated by reference herein in its entirety.

Nevertheless, issues remain with accurately predicting drying time. In some cases, a drying cycle may conclude earlier than the predicted drying time that was initially or subsequently displayed during operation of the dryer appliance. In these cases, articles can be left in the dryer appliance to wrinkle for substantial periods of time. In other cases, a drying cycle may continue past the predicted drying time. The display of predicted drying time can revert to “racetrack” mode, outputting a rotating display of light indicators, or another indicator output to indicate that the predicted drying time is being adjusted. This can be frustrating to a user to expects to see a relatively accurate drying time display.

Accordingly, improved dryer appliances and methods for operating dryer appliances are desired. In particular, dryer appliances and methods that provide improved drying time prediction accuracy would be advantageous.

BRIEF DESCRIPTION OF THE INVENTION

In one embodiment, a method for operating a dryer appliance is provided. The method includes calculating an initial cycle time, and counting down from the initial cycle time for an initial countdown time. The method further includes determining, during the step of counting down from the initial cycle time for the initial countdown time, whether a load size value and an air flow value have been established. The method further includes calculating, when the load size value and the air flow value have been established, a first updated remaining cycle time based on the load size value and the air flow value.

In another embodiment, a dryer appliance is provided. The dryer appliance includes a cabinet defining an interior, and a drum positioned within the interior, the drum defining a chamber for receipt of articles for drying. The dryer appliance further includes a heating assembly, an inlet duct providing fluid communication between the drum and the heating assembly, and an outlet assembly, the outlet assembly comprising a vent duct and an exhaust conduit. The dryer appliance further includes a controller. The controller is operable for calculating an initial cycle time, and counting down from the initial cycle time for an initial countdown time. The controller is further operable for determining, during the step of counting down from the initial cycle time for the initial countdown time, whether a load size value and an air flow value have been established. The controller is further operable for calculating, when the load size value and the air flow value have been established, a first updated remaining cycle time based on the load size value and the air flow value.

DETAILED DESCRIPTION

FIG. 1illustrates a dryer appliance10according to an exemplary embodiment of the present subject matter.FIG. 2provides another perspective view of dryer appliance10with a portion of a cabinet or housing12of dryer appliance10removed in order to show certain components of dryer appliance10. While described in the context of a specific embodiment of dryer appliance10, using the teachings disclosed herein it will be understood that dryer appliance10is provided by way of example only. Other dryer appliances having different appearances and different features may also be utilized with the present subject matter as well. Dryer appliance10defines a vertical direction V, a lateral direction L, and a transverse direction T. The vertical direction V, lateral direction L, and transverse direction T are mutually perpendicular and form and orthogonal direction system.

Cabinet12includes a front panel14, a rear panel16, a pair of side panels18and20spaced apart from each other by front and rear panels14and16, a bottom panel22, and a top cover24. These panels and cover collectively define an external surface60of the cabinet12and an interior62of the cabinet. Within interior62of cabinet12is a drum or container26. Drum26defines a chamber25for receipt of articles, e.g., clothing, linen, etc., for drying. Drum26extends between a front portion37and a back portion38, e.g., along the lateral direction L. In exemplary embodiments the drum26is rotational. Alternatively, however, the drum26may be fixedly mounted within the interior62.

Drum26is generally cylindrical in shape, having an outer cylindrical wall or cylinder28and a front flange or wall30that may define an entry32of drum26, e.g., at front portion37of drum26, for loading and unloading of articles into and out of chamber25of drum26. Drum26also includes a back or rear wall34, e.g., at back portion38of drum26. In alternative embodiments, entry32may be defined in top cover24and cylinder28, and front wall30may be a generally solid wall.

A motor31may be in mechanical communication with a blower48such that motor31rotates a blower fan49, e.g., of the blower48. Blower48is configured for drawing air through chamber25of drum26, e.g., in order to dry articles located therein as discussed in greater detail below. In alternative exemplary embodiments, dryer appliance10may include an additional motor (not shown) for rotating fan49of blower48independently of drum26.

Drum26may be configured to receive heated air that has been heated by a heating assembly40, e.g., in order to dry damp articles disposed within chamber25of drum26. Heating assembly40includes a heater43, such as a gas burner or an electrical resistance heating element, for heating air. As discussed above, during operation of dryer appliance10, motor31rotates fan49of blower48such that blower48draws air through chamber25of drum26. In particular, ambient air enters heating assembly40via an entrance51due to blower48urging such ambient air into entrance51. Such ambient air is heated within heating assembly40and exits heating assembly40as heated air. Blower48draws such heated air through inlet duct41to drum26. The heated air enters drum26through an outlet42of duct41positioned at rear wall34of drum26.

Within chamber25, the heated air can remove moisture, e.g., from damp articles disposed within chamber25. This internal air in turn flows from the chamber25through an outlet assembly64positioned within the interior62. The outlet assembly64includes a vent duct66, the blower48, and an exhaust conduit52. The exhaust conduit52is in fluid communication with the vent duct66via the blower48. During a dry cycle, internal air flows from the chamber25through the vent duct66to the blower48and through the blower48to the exhaust conduit52, and is exhausted from the exhaust conduit52.

In exemplary embodiments, vent duct66can include a filter portion70and an exhaust portion72. The exhaust portion72may be positioned downstream of the filter portion70(in the direction of flow of the internal air). A screen filter of filter portion70(which may be removable) traps lint and other particulates as the internal air flows therethrough. The internal air may then flow through the exhaust portion72and the blower48to the exhaust conduit52.

After the clothing articles have been dried, they are removed from the drum26via entry32. A door33provides for closing or accessing drum26through entry32.

One or more selector inputs80, such as knobs, buttons, touchscreen interfaces, etc., may be provided on a cabinet backsplash81and in communication with a processing device or controller82. Signals generated in controller82operate motor31and heating assembly40, including heater43, in response to the position of selector inputs80. Additionally, a display84, such as an indicator light or a screen, may be provided on cabinet backsplash82. The display84may be in communication with the controller82, and may display information in response to signals from the controller82. As used herein, “processing device” or “controller” may refer to one or more microprocessors or semiconductor devices and is not restricted necessarily to a single element. The processing device can be programmed to operate dryer appliance10. The processing device may include, or be associated with, one or more memory elements such as e.g., electrically erasable, programmable read only memory (EEPROM).

In some embodiments, dryer appliance10may additionally include one or more sensors. For example, dryer appliance10may include one or more temperature sensors90. A temperature sensor90may be operable to measure internal temperatures in the dryer appliance10. In some embodiments, for example, a temperature sensor90may be disposed in the inlet duct41, such as at outlet42of the inlet duct41, which corresponds to the inlet to drum26. Additionally or alternatively, for example, a temperature sensor90may be disposed in the drum26, such as in the chamber25thereof, at an outlet of the drum26such as in vent duct66, or in any other suitable location within the dryer appliance10. Temperature sensors90may be in communication with the controller82, and may transmit readings to the controller82as required or desired.

Dryer appliance10may further include, for example, a dampness sensor92. The dampness sensor92may be operable to measure the dampness of articles within the chamber25during operation of the dryer appliance10. In particular, the dampness sensor92may measure voltages associated with dampness, as is generally understood. In exemplary embodiments, dampness sensor92may be a moisture sensor. The dampness sensor92may be disposed on rear wall34or at any other suitable location within the dryer appliance10. Dampness sensor92may be in communication with the controller82, and may transmit readings to the controller82as required or desired.

Dryer appliance10may further include, for example, an air flow sensor94. The air flow sensor94may be operable to measure air flow through the dryer appliance10during operation of the dryer appliance10. The air flow sensor94may be disposed within the inlet duct41, exhaust conduit52, or at any other suitable location within the dryer appliance10. Air flow sensor94may be in communication with the controller82, and may transmit readings to the controller82as required or desired. Notably, in alternative embodiments, air flow may be calculated without the use of an air flow sensor94, such as though use of a suitable algorithm as is generally understood in the art. Such algorithm may in some embodiments utilize temperatures measured by temperature sensor(s)90. Examples of suitable algorithms are provided in, for example, U.S. Pat. No. 7,322,126, filed on Apr. 27, 2006 and issued on Jan. 29, 2008, which is incorporated by reference herein in its entirety.

Dryer appliance10may further include, for example, a weight sensor96. The weight sensor96may be operable to measure the weight of a load of articles during operation of the dryer appliance10. The weight sensor96may be disposed on outer wall28, or at any other suitable location within the dryer appliance10. Weight sensor96may be in communication with the controller82, and may transmit readings to the controller82as required or desired. Notably, in alternative embodiments, weight may be calculated without the use of a weight sensor, such as though use of a suitable algorithm as is generally understood in the art. Such algorithm may in some embodiments utilize temperatures measured by temperature sensor(s)90. Examples of suitable algorithms are provided in, for example, U.S. Pat. No. 7,322,126, filed on Apr. 27, 2006 and issued on Jan. 29, 2008, which is incorporated by reference herein in its entirety.

It should be understood that, whileFIGS. 1 and 2illustrate embodiments wherein dryer appliance10is a horizontal axis dryer appliance, in other embodiments dryer appliance10may be, for example, a vertical axis dryer appliance or another suitable dryer appliance. In a vertical axis dryer appliance10, for example, cylinder28of drum26may extend along the vertical axis V between rear wall34and front wall30. Accordingly, the present disclosure is not limited to horizontal axis dryer assemblies. Rather, any suitable dryer appliance is within the scope and spirit of the present disclosure.

Referring now toFIGS. 3 and 4, the present disclosure is further directed to methods for operating dryer appliances, as denoted generally by reference numeral100. Methods in accordance with the present disclosure may advantageously provide improved accuracy in the prediction of the cycle time for the dryer appliance10, through advantageous use of various values associated with the load of articles being dried and advantageous updating of the cycle time prediction during operation. In particular, use of the load size and the air flow during operation of the dryer appliance10facilitate more accurate cycle time prediction. Further, updating of the predicted cycle time at various dampness thresholds for the load of articles may further facilitate more accurate cycle time prediction.

Advantageously, in exemplary embodiments, the various method steps discussed herein may be performed by controller82, which may for example be in communication with sensors90,92,94,96, algorithms and/or other various components such as selector inputs80as discussed herein.

Method100may include, for example, the step110of calculating an initial cycle time112. The initial cycle time112calculation may, for example, be based on various inputs provided by a user through use of the selector inputs80, including for example a cycle value114, a heat value116, and a dryness value118. Cycle value114may be based on the cycle selected by a user, such as a normal cycle, cottons, delicate, mixed load, towels, etc. Each cycle may be assigned a value, which may be determined through experimental iteration and programmed into the controller82. Heat value116may be based on a desired amount of heat selected by a user, such as high heat, normal heat, low heat, etc. Each cycle may be assigned a value, which may be determined through experimental iteration and programmed into the controller82. Dryness value118may be based on a desired dryness selected by a user, such as normal dry, extra dry, damp, slightly damp, etc. Each cycle may be assigned a value, which may be determined through experimental iteration and programmed into the controller82. Initial cycle time112may additionally be based on other values, such as a detangle value, an efficiency value, etc., each of which may be assigned a value, which may be determined through experimental iteration and programmed into the controller82. Additionally, initial cycle time112may be based on a cool down value119, which may be determined through experimental iteration and programmed into the controller82. Initial cycle time112may, for example, be calculated by multiplying cycle value114(which may be a base time for the selected cycle) by various other values, such as heat value116, dryness value118, etc. (which may be multipliers) and then adding cool down value119to the resulting corrected cycle value.

Method100may further include, for example, the step120of counting down from the initial cycle time112for an initial countdown time122. The initial countdown time122may, for example, be a predetermined amount of time that may be programmed into the controller82. In some embodiments, the time may be, for example, between approximately 2 minutes and approximately 5 minutes. In some embodiments, the initial countdown time122may be based on the cycle value114or another suitable value, and a specific time122may be utilized depending on the cycle or other variable chosen. In other embodiments, the initial countdown time122may be independent of such values and variables, and may simply be a programmed amount of time.

Method100may further include, for example, the step130of determining whether a load size value132and an air flow value134have been established. Such step130may occur, for example, during the step120of counting down from the initial cycle time112for the initial countdown time122. The load size value132may be based on, for example, the weight of a load of articles sensed by weight sensor96or calculated by a suitable algorithm as discussed herein, or the size of the load as measured using another suitable measurement apparatus or method, as are generally understood in the art. In some embodiments, categories for the load size value132may include, for example, small, large, medium, etc. The air flow value134may be based on, for example, the air flow sensed by air flow sensor94, calculated by a suitable algorithm as discussed herein, or measured using another suitable measurement apparatus or method, as is generally understood in the art. In some embodiments, categories for the air flow value134may include, for example, low, high, medium, etc.

In accordance with step130, during the step120of counting down, it is determined whether a load size value132and an air flow value134have been established. Method100may further include, for example, the step140of calculating an updated remaining cycle time142, such as a first updated remaining cycle time142, based on the load size value132and the air flow value134. Such step140may occur, for example, when the load size value132and the air flow value134have been established, such as during the initial countdown time122. The first updated remaining cycle time142may in exemplary embodiments be further based on the cycle value114, heat value116, dryness value118, cool down value119, and other suitable values as discussed above in the context of step120.

In some embodiments, each category of load size value132and air flow value134may be assigned a value, which may be determined through experimental iteration and programmed into the controller82. In other embodiments, a value, which may be known as a correction factor, may be assigned to a set or combination of categories. For example, a value may be assigned to each combination of categories for load size value132, air flow value134, and cycle value114. These values may be determined through experimental iteration and programmed into the controller82.

Updated remaining cycle time142may, for example, be calculated by initially calculating an updated cycle value. The updated cycle value may be calculated by, for example, dividing the correction factor by the initial cycle time112, and multiplying this result by the cycle value114. After obtaining the updated cycle value, the updated remaining cycle time142may be determined by multiplying the updated cycle value by the various other values, such as heat value116, dryness value118, etc. and then adding cool down value119to the resulting updated corrected cycle value. Finally, the total elapsed time of the cycle may be subtracted from this value to obtain an updated remaining cycle time142.

The calculation of updated remaining cycle time142in accordance with the present disclosure may advantageously improve the accuracy of the cycle time prediction, by utilizing load size values132and the air flow values134to update the cycle time prediction during operation of the appliance10. Further, additional updating as discussed herein may further increase the cycle time prediction accuracy.

For example, method100may further include the step150of counting down from the first updated remaining cycle time142for a first subsequent countdown time152. The first subsequent countdown time152may, for example, be a predetermined amount of time that may be programmed into the controller82. In some embodiments, the first subsequent countdown time152may be based on the cycle value114or another suitable value, and a specific time152may be utilized depending on the cycle or other variable chosen. In other embodiments, the first subsequent countdown time152may be independent of such values and variables, and may simply be a programmed amount of time.

Method100may further include, for example, the step155of determining whether a first dampness value157has been reached. Such step155may occur, for example, during the step150of counting down from the first updated remaining cycle time142for the first subsequent countdown time152. The first dampness value157may be based on, for example, the dampness sensed by the dampness sensor92, which may for example be a voltage or other suitable variable. The first dampness value157may be determined through experimental iteration and programmed into the controller82. Notably, the value157may further be associated with a specific category of dryness value118, such as damp.

In some cases, the threshold of the first dampness value157may not be reached during first subsequent countdown time152. Method100may thus further include, for example, the step160of transmitting an extended time indicator162. Such step160may occur, for example, when the first subsequent countdown time152expires and, at the time of this expiration, the first dampness value157has not been reached. The extended time indicator162may, for example, be transmitted to the display84. In some embodiments, the display84may indicate a “racetrack” mode when the extended time indicator162is transmitted thereto. The extended time indicator162may remain and continue to be transmitted until the first dampness value157is reached, at which point the method may proceed to step165as discussed below.

In other cases, the threshold of the first dampness value157may be reached during first subsequent countdown time152. In some embodiments, as illustrated inFIG. 3, method100may thus further include, for example, the step165of calculating a second updated remaining cycle time167based on the load size value132and the air flow value134. Such step165may occur when, for example, the first dampness value157has been reached.

For example, in some embodiments, a second value, or correction factor, may be assigned to a set or combination of categories of load size value132and air flow value134. For example, a second value may be assigned to each combination of categories for load size value132, air flow value134, and cycle value114. These second values may be determined through experimental iteration and programmed into the controller82.

Second updated remaining cycle time167may, for example, be calculated by multiplying an elapsed time to reach the first dampness value157, denoted by the reference numeral169, by the various other values, such as heat value116, dryness value118, etc. and then subtracting the elapsed time169from the result. Further, this result may then be multiplied by a second correction factor. Finally, the total elapsed time of the cycle may be subtracted from this value to obtain a second updated remaining cycle time167.

In some embodiments, method100may further include the step170of counting down from the second updated remaining cycle time167for a second subsequent countdown time172. The second subsequent countdown time172may, for example, be a predetermined amount of time that may be programmed into the controller82. In some embodiments, the second subsequent countdown time172may be based on the cycle value114or another suitable value, and a specific time172may be utilized depending on the cycle or other variable chosen. In other embodiments, the second subsequent countdown time172may be independent of such values and variables, and may simply be a programmed amount of time.

Method100may further include, for example, the step175of determining whether a second dampness value177has been reached. Such step175may occur, for example, during the step170of counting down from the second updated remaining cycle time167for the second subsequent countdown time172. The second dampness value177may be based on, for example, the dampness sensed by the dampness sensor92, which may for example be a voltage or other suitable variable. The second dampness value177may be determined through experimental iteration and programmed into the controller82. Notably, the value177may be less than the first dampness value157, and may further be associated with a specific category of dryness value118, such as less damp or slightly damp.

In some cases, the threshold of the second dampness value177may not be reached during second subsequent countdown time172. Method100may thus further include, for example, the step180of transmitting an extended time indicator182. Such step180may occur, for example, when the second subsequent countdown time172expires and, at the time of this expiration, the second dampness value177has not been reached. The extended time indicator182may, for example, be transmitted to the display84. In some embodiments, the display84may indicate a “racetrack” mode when the extended time indicator182is transmitted thereto.

In other cases, the threshold of the second dampness value177may be reached during second subsequent countdown time172. In some embodiments, as illustrated inFIG. 3, method100may thus further include, for example, the step185of calculating a third updated remaining cycle time187based on the load size value132and the air flow value134. Such step185may occur when, for example, the second dampness value177has been reached.

For example, in some embodiments, a third value, or correction factor, may be assigned to a set or combination of categories of load size value132and air flow value134. For example, a third value may be assigned to each combination of categories for load size value132, air flow value134, and cycle value114. These third values may be determined through experimental iteration and programmed into the controller82.

Third updated remaining cycle time187may, for example, be calculated by multiplying an elapsed time to reach the second dampness value177, denoted by the reference numeral189, by the various other values, such as heat value116, dryness value118, etc. and then subtracting the elapsed time189from the result. Further, this result may then be multiplied by a third correction factor. Finally, the total elapsed time of the cycle may be subtracted from this value to obtain a third updated remaining cycle time187.

In some embodiments, method100may still further include the step190of counting down from the third updated remaining cycle time187for a third subsequent countdown time192. The third subsequent countdown time192may, for example, be a predetermined amount of time that may be programmed into the controller82. In some embodiments, the third subsequent countdown time192may be based on the cycle value114or another suitable value, and a specific time192may be utilized depending on the cycle or other variable chosen. In other embodiments, the third subsequent countdown time192may be independent of such values and variables, and may simply be a programmed amount of time.

Method100may further include, for example, the step195of determining whether a final dampness value197has been reached. Such step195may occur, for example, during the step190of counting down from the third updated remaining cycle time187for the third subsequent countdown time192. The final dampness value197may be based on, for example, the dampness sensed by the dampness sensor92, which may for example be a voltage or other suitable variable. The final dampness value197may be determined through experimental iteration and programmed into the controller82. Notably, the value197may be less than the first dampness value157and the second dampness value177, and may further be associated with a specific category of dryness value118, such as normal dry, extra dry, or any other suitable dryness level that is dryer than the damp or slightly/less damp settings discussed herein. In exemplary embodiments, the final dampness value197is a value associated with the selected dryness value118.

In some cases, the threshold of the final dampness value197may not be reached during third subsequent countdown time192. Method100may thus further include, for example, the step200of transmitting an extended time indicator202. Such step200may occur, for example, when the third subsequent countdown time192expires and, at the time of this expiration, the final dampness value197has not been reached. The extended time indicator202may, for example, be transmitted to the display84. In some embodiments, the display84may indicate a “racetrack” mode when the extended time indicator202is transmitted thereto.

In other cases, the threshold of the final dampness value197may be reached during third subsequent countdown time192. In some embodiments, as illustrated inFIG. 3, method100may thus further include, for example, the step205of calculating a final updated remaining cycle time207based on the load size value132and the air flow value134. Such step205may occur when, for example, the final dampness value197has been reached. Calculation of the final updated remaining cycle time207is generally understood in the art. Examples of suitable methods for calculation of the final updated remaining cycle time207are provided in, for example, U.S. Pat. No. 7,013,578, filed on Apr. 23, 2004 and issued on Mar. 21, 2006, which is incorporated by reference herein in its entirety.

Once the final updated remaining cycle time207is calculated, a final countdown period and cool down period may be completed. For example, in some embodiments, method100may further include the step210of counting down from the final updated remaining cycle time207until the cool down value119is reached. Once the cool down value119is reached, a cool down cycle may be performed, as is generally understood in the art.

It should be noted that, in the above described embodiments, method100may include various steps that continue beyond the determination of a first dampness value157, which in exemplary embodiments may be associated with a damp category, and a second dampness value177, which in exemplary embodiments may be associated with a slightly damp or less damp category. However, in some embodiments, a user may have selected damp or slightly/less damp as a dryness value118. In these embodiments, method100need not include various of these steps. Rather, a truncated method may be utilized, wherein for example the method proceeds from step155to step205′ as illustrated inFIG. 4or from step175to a similar final updated remaining cycle time step (not illustrated). Step205′ may include, for example, calculating a final updated remaining cycle time207based on the load size value132and the air flow value134. Such step205′ may occur when, for example, the first dampness value157has been reached. Calculation of the final updated remaining cycle time207is generally understood in the art. Examples of suitable methods for calculation of the final updated remaining cycle time207are provided in, for example, U.S. Pat. No. 7,013,578, filed on Apr. 23, 2004 and issued on Mar. 21, 2006, which is incorporated by reference herein in its entirety.