Self programming clothes dryer system

Information

  • Patent Grant
  • 6519871
  • Patent Number
    6,519,871
  • Date Filed
    Friday, May 25, 2001
    23 years ago
  • Date Issued
    Tuesday, February 18, 2003
    21 years ago
Abstract
A method and apparatus for operating an automatic cycle of a clothes dryer wherein after initiation of an automatic cycle, a CPU displays the expected time remaining during the current cycle. At various times during the cycle, the expected time remaining is updated by comparing the time required to reach certain moisture levels of the articles contained therein to reference times. The comparison also results in the expected times being updated for future uses of the clothes dryer. Finally, the invention includes a system for updating the amount of time required to reach a desired final temperature during a cooldown sequence.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a control system for a clothes dryer. In particular, a moisture sensor is provided to terminate a drying process when the amount of moisture present in the clothes inside the dryer reaches a desired level as selected by a user. Additionally, the clothes dryer of this invention includes a drying schedule which estimates the amount of drying time left in the current cycle, by taking into account differences between an initial estimation and the final result each time the dryer has been run. The length of a cooldown sequence is also updated.




2. Discussion of the Prior Art




It is well known in the art to provide a clothes dryer with a simple time-dry control, in addition to a sensor-dry mode. When the time-dry control is used, the user places the wet articles inside the dryer and selects a duration for the drying process. Because there is little or no automatic control or adjustment during the process, the drying process simply continues until the time expires. The result can be inefficient, because it is difficult for a user to accurately estimate the time required to reach a desired, final moisture level prior to operating the machine.




In comparison, sensor-dry modes are provided to automatically control a drying operation. Specifically, when a sensor-dry mode is selected, the user places wet articles inside the dryer drum and selects a final dryness level. Instead of forcing the user to guess how long the process should take, the machine stops when the desired dryness level is reached. For this purpose, the machine includes at least one sensor for detecting the level of moisture of the articles. The machine simply operates until the moisture sensor detects the final desired dryness level selected by the user. By terminating the process upon achieving the desired final dryness level, there is no need to re-start the process to finish incomplete drying. In addition, extra energy is not expended to dry the articles beyond the desired dryness level.




Electronic controls have been developed to assist in the operation of such an automatic drying processes. For example, U.S. Pat. No. 3,762,064, to Offut, discloses a system for automatic operation of a dryer in which extra time is added to a drying process according to a predetermined table. A selection of a dryness level beyond a predetermined level (e.g. damp-dry) results in the addition of extra time. The duration of this extra time is dependent upon the length of time required to reach the predetermined dryness level and the desired final dryness level selected by the user. While this system incorporates a moisture sensor for making a drying operation more efficient, this system is nevertheless highly inefficient, because only one threshold dryness level is detected and the final dryness level is never actually measured, as the time to reach that level is only estimated. Therefore, just as in time dry modes, the articles will often be either under-dried and still wet, or over-dried. Even if the system were able to accurately estimate the time required to be added to a single cycle to reach a desired dryness level, the estimation would need to be performed each time the clothes dryer is run. Therefore, the system does not allow the circuitry to “learn” about how the clothes dryer is being run to more efficiently operate and give more accurate time readings for completion of a drying cycle.




U.S. Pat. No. 4,477,892, to Cotton, represents an improvement over the system disclosed in the '064 patent, and includes sensors or electrodes which contact the wet articles to determine the current moisture level contained therein. Through the system of this patent, the current moisture level inside the machine can be measured at a variety of continuous levels. By comparing the number of conductive electrode “hits” during a given time period, it is possible to estimate the current degree of dryness. In any event, when a sense dry mode is selected in a conventional clothes dryer, the user is given little, if any, indication that the cycle is coming to an end.




It is also common to utilize a cooldown sequence or procedure at the conclusion of a drying cycle. During this cooldown procedure, cool or non-heated air is passed through the drum of the clothes dryer for a predetermined period of time to more slowly bring articles of clothing down to room temperature and help prevent creasing therein. In the majority of clothes dryers with a cooldown procedure, the cooldown time is either determined by the user or is preset as a static and unchangeable period of time.




As a result, cooldown sequences can be as inefficient as certain drying operations. First, for a user to correctly estimate the amount of time required for a cooldown cycle, he must take into account, (1) temperature of the drying cycle, (2) clothes load, (3) clothes type, and (4) temperature of the cool air being introduced. Hence, accurate estimations are nearly impossible, and the load is often not cooled sufficiently, or is “over-cooled”. Even when a preset cooldown duration is utilized, the result is usually the same. Because individuals use their machines differently, i.e. with different typical clothes loads, different typical clothes type mixtures, and have varying cool air inlet temperatures, any preset cooldown duration will, in all likelihood, be inaccurate.




Therefore, there exists the need in the art to provide a control system for a clothes dryer which allows for an adjustable duration setting for both a sensor dry estimation and a cooldown sequence for subsequent uses.




SUMMARY OF THE INVENTION




The present invention is particularly directed to a control system for a clothes dryer including a timer and a sensor which measures a drying parameter to calculate how long, with respect to a predetermined time, the clothes dryer needs to be operated to reach a particular condition and to update the predetermined time for subsequent uses. Additionally, a display is included to show the user the amount of time remaining in the current drying cycle, according to the predetermined time.




In a first embodiment, a moisture sensor is included to measure a current moisture level of articles contained within the clothes dryer. Prior to initiating a drying cycle, the user selects a drying temperature and a dryness level. Through a CPU, the control system determines and displays an expected drying cycle time. At certain times in the drying process, the control system checks the actual duration against the expected duration and updates the time remaining displayed. In addition, the expected duration for subsequent cycles is altered. Specifically, during the first few, preferably ten, runs of the clothes dryer, one-half of the difference between the actual run time and the expected run time is respectively added or subtracted from the expected run time value. And, after each later operation, i.e., operations following the first ten, the expected run time is altered by one-quarter of the difference.




By calculating the expected run time, the expected remaining duration can be advantageously displayed to the user. Accordingly, each time the clothes dryer is run, the time required to reach the selected dryness condition is used to update the existing expected time, to more accurately estimate the time remaining. In this manner, average load conditions are “learned” by the clothes dryer.




The “average” load condition is also used to adjust the length of a cooldown sequence at the end of the drying cycle. In the second embodiment, the clothes dryer includes a temperature sensor for measuring the temperature of an exhaust air flow. Specifically, the control system of the invention measures the temperature of the exhaust air flow when the cooldown sequence is complete. If the temperature is equal to or over 100° F. (37.8° C.), the control system adds one minute to the next cooldown sequence. If, however, the temperature of the exhaust air flow is less than 100° F. (37.8° C.), one minute is subtracted from the next cooldown sequence.




Additional objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment thereof, when taken in conjunction with the drawings, wherein like reference numerals refer to corresponding parts in the several views.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a front perspective view of a clothes dryer incorporating a drying schedule according to the invention;





FIG. 2

is a front view of a control panel provided on the clothes dryer of

FIG. 1

;





FIG. 3A

is a diagrammatic representation of an initial portion of drying control sequence according to the invention; and





FIG. 3B

is a diagrammatic representation of a latter portion of a drying control sequence according to the invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




A clothes dryer


1


of the current invention is shown in FIG.


1


and generally includes an outer cabinet


10


, having an opening leading to a rotatable drum


14


and a door


18


for closing the opening. Disposed on the upper surface of the outer cabinet is a control panel


22


establishing a desired operational sequence for programming the clothes dryer


1


of the invention.





FIG. 2

depicts a close-up view of control panel


22


and includes a plurality of buttons and other elements for controlling clothes dryer


1


. Although control panel


22


is described below in a specific arrangement, it is understood that the particular arrangement is only exemplary, as a wide range of layouts would suffice. Accordingly, disposed on the left side of control panel


22


is a temperature selector


40


, which includes buttons for selecting the heat output of the clothes dryer


1


. In the most preferred embodiment, temperature selector


40


includes an air fluff button


42


, a delicate button


44


, a medium button


46


and a regular button


48


.




Next to temperature selector


40


is a moisture monitor


55


for displaying the current moisture state of articles contained within clothes dryer


1


. Moisture monitor


55


is shown as including a set of LEDs


58


for indicating the specific moisture level. Because the LEDs


58


are vertically arranged, individual LEDs


58




a-f


can be illuminated to indicate a current moisture level. For example, a low moisture level can be signified by illuminating only LED


58




a


, while a higher moisture level can be shown by illuminating LED


58




d


alone or LEDs


58




a


,


58




b


,


58




c


and


58




d


simultaneously.




Proximate to moisture monitor


55


is a signal controller


62


. Signal controller


62


is provided to selectively regulate the operation of a buzzer (not shown), and includes an OFF button


64


and an ON button


66


. The selection of ON button


66


causes the buzzer to sound upon completion of the drying operation, while selection of OFF button


62


prevents the buzzer from sounding upon completion of the drying operation. Additionally, control panel


22


includes a start button


70


for commencing operation of clothes dryer


1


.




Control panel


22


also includes a display


75


for showing a variety of information to the user. If display


75


is used to only give the user the amount of time remaining in the current cycle by displaying a two-digit number representing a number of minutes, a simple arrangement of two seven-segment LEDs may be utilized to represent the numbers zero through ninety-nine. However, if more information, such as cycle selected, temperature selected, or any of a variety of machine conditions or error messages are to be displayed to the user, a standard LCD panel or LED interface would be more appropriate. In such a case, display


75


can take the form of a 128×96 dot matrix display.




Finally, control panel


22


includes a control dial


100


for programming clothes dryer


1


. Disposed on the periphery of the center surface of dial


100


is a location pointer


101


which indicates an established setting for dial


100


. Annularly disposed about the periphery of dial


100


is indicia


103


which illustrates the various settings. Specifically, indicia


103


includes a first sense-dry zone


105


, a second sense-dry zone


10


and a time-dry zone


113


, each defining a portion of indicia


103


and designed to indicate the mode of dryer operation, i.e. a sense-dry mode or a time-dry mode. Sense-dry zones


105


and


110


each include a MORE DRY setting


120




a


,


120




b


and a LESS DRY setting


125




a


,


125




b


with continuous levels therebetween. First sense-dry zone


105


also includes a cooldown setting


128


. A plurality of time increments


130


are defined by indicia


103


in time-dry zone


113


. Finally, disposed between each of zones


105


,


110


and


113


are OFF positions


132


. Depending upon the operational state of clothes dryer


1


, dial


100


, and hence location pointer


101


, will reference the appropriate indicia


103


.




With reference to

FIG. 1

, clothes dryer


1


also includes a control circuit generally indicated at


200


. Specifically a CPU


210


is provided with a drying schedule


215


stored therein, preferably stored in an internal memory (not shown) of CPU


210


, in addition to a timer


220


. However, the memory may be external or remote from CPU


210


. Connected to both display


75


and CPU


210


is a display driving circuit


225


. A moisture sensor


230


, also linked to moisture monitor


55


, is provided as an additional input to CPU


210


, and may be any conventional moisture sensor known in the art, such as the moisture sensor described in U.S. Pat. No. 4,477,982, to Cotton, herein incorporated by reference. A temperature sensor


240


is also connected to CPU


210


for monitoring the temperature of an exhaust air flow during operation of clothes dryer


1


. A motor


250


is also included to rotate dial


100


. CPU


210


is also used to direct the operation of a heater


260


.




After wet articles are placed within drum


14


, a user selects an operation in a generally conventional manner. First, temperature selector


42


is used to chose a desired operational temperature for clothes dryer


1


. While selection of regular button


48


uses the highest temperature setting and results in the fastest drying time, the “regular” setting may be too hot for some articles. Therefore, additional temperature levels are provided. Before pressing start button


70


and beginning operation of clothes dryer


1


, the user rotates dial


100


from OFF setting


132


into time-dry


113


, first sense-dry zone


105


or second sense-dry zone


110


. If dial


100


is rotated such that location pointer


101


is in a time-dry zone


113


, the clothes dryer


1


is in time-dry mode, and simply operates until the time indicated by time increment


130


expires. CPU


210


directs motor


250


to rotate dial


100


at a rate coinciding to time increments


130


.




The present invention is particularly directed to the manner in which clothes dryer


1


is used in a sense-dry mode, as indicated by the position of dial


100


, wherein clothes dryer


1


continues to run until the dryness level selected by rotating dial


100


is reached. Once start button


70


is pressed, CPU


210


begins operation of clothes dryer


1


. After starting rotation of drum


14


and initiating heating, CPU


210


reads the position of dial


100


and, through drying schedule


215


, determines an expected drying time. In a preferred embodiment, drying schedule


215


is essentially a table of expected drying times for the various dryness levels and temperature selections but, in another embodiment, drying schedule


215


includes an algorithm into which the temperature selection and selected dryness level are input for determining the expected drying time. In accordance with the invention, prior to the first operation of clothes dryer


1


, the following table is preferably loaded into memory as an example of the expected drying times, in minutes, for specified temperatures and dryness levels:


















TABLE 1











Damp Dry




Less Dry




Normal Dry




More Dry




Very Dry





























Extra Low




40




48




58




64




70






Low




38




44




54




60




66






Medium




35




40




52




58




64






Regular




32




38




50




56




62














For example, if medium button


46


and NORMAL DRY are selected, CPU


210


would read thirty-eight minutes as an expected drying time. In order to give the user a visual indication as to the expected finish time, CPU


210


also directs display driving circuit


225


to show the current expected time remaining on display


75


. As can be seen from the above table, the times for MORE DRY and VERY DRY are calculated by adding six and twelve minutes respectively to the times found in the NORMAL DRY column. Because display


75


is initiated at the outset of the drying cycle and initially indicates the number read from the table, the reading on display


75


is decremented every minute as directed by timer


220


and display driving circuit


225


.




The table of expected drying times is updated every time clothes dryer


1


completes a cycle, both for the current cycle and for subsequent cycles. Because the articles contained within drum


14


of clothes dryer


1


must pass through lower dryness levels on the way to higher dryness levels, the expected drying times are updated as the various dryness levels are passed. For example, if VERY DRY is selected, drying schedule


215


is updated as each of DAMP DRY, LESS DRY, NORMAL DRY and MORE DRY are reached, resulting in five independent updates of drying schedule


215


.




Additionally, CPU


210


also updates drying schedule


215


for “dryer” dryness levels when certain dryness levels are selected. In a preferred embodiment, if the user selects DAMP DRY, both the LESS DRY and NORMAL DRY expected drying times are updated as DAMP DRY is reached. However, if the user selects more dry, for example, drying schedule


215


will be updated as the moisture level passes through each of the respective dryness levels.




As a particular dryness level is reached, drying schedule


215


is updated for the selected temperature. The difference between the duration of the current cycle, or cycle time, and the expected drying time (as read from the table of drying schedule


215


) is calculated. One-quarter of the calculated difference is respectively added or subtracted to the expected drying time for that dryness level and selected temperature. Because the time differences between the different dryness levels are constant, the entire row, i.e., expected drying times for a temperature selection, is updated. In a preferred embodiment, as exemplified in Table 1, the expected drying times for MORE DRY and VERY DRY are calculated from adding six and twelve minutes respectively to the expected drying time for NORMAL DRY. The remainder of constant differences can be determined by analyzing Table 1. For example, because the difference between the expected times for LESS DRY and NORMAL DRY for the regular temperature selection is twelve minutes, adding any time to the expected time to LESS DRY would result in the same amount being added to NORMAL DRY as well. An example of this procedure is exemplified in

FIG. 3

, as also described in detail below.




In accordance with the most preferred form of the invention, the first ten times clothes dryer


1


is run a “level set” function is performed and the dryness schedule


215


for each of the temperatures and dryness levels is updated. Specifically, one-half of the calculated difference is respectively added or subtracted to the expected times for medium and regular temperatures and one-quarter of the calculated difference is added or subtracted to the lower two temperature selections. After the first ten cycles, one-quarter of the calculated difference is either added or subtracted, depending on whether the calculated difference is positive or negative, to the expected time for only the selected temperature. In a most preferred embodiment, only the times for the selected dryness level are updated, rather than for each desired dryness level, after the first ten cycles.




Drying schedule


215


also preferably includes a cooldown sequence to be used when dial


100


is rotated to each of first and second sense-dry zones


105


and


110


, with the cooldown time being substantially greater with first sense-dry zone


105


. After the articles are dried to the selected dryness level, as sensed by moisture sensor


230


, lower temperature air, for example, air from inside the room, is introduced into drum


14


to quickly cool the articles, while drum


14


is still tumbling. This reduces or prevents wrinkles or creases from forming once the clothes are dry. The procedure for programming CPU


210


with the position of dial


100


may be any conventional method known in the art or the procedure described in commonly assigned U.S. Patent Application entitled, “Strategy for Dryness Detection in a Clothes Dryer”, filed on even date herewith and incorporated herein by reference.




If dial


100


has been rotated into first sense-dry zone


105


, when the articles reach the selected dryness level, CPU


210


causes cool air to be introduced into drum


14


to reduce the temperature therein. CPU


210


then reads, or calculates if an algorithm is utilized, a cooldown time from drying schedule


215


. Just as for expected drying time, the cooldown time may be in the form of a number or an algorithm through which a number may be calculated indicating the amount of time the cooldown sequence is to continue. CPU


210


also causes display driving circuit


225


to direct display


75


to indicate the number of minutes remaining in the cooldown sequence. Timer


220


is used to decrement display


75


. The cooldown sequence then continues for the time indicated by the cooldown time, as read from drying schedule


215


.




Once the cooldown time has expired and display


75


reads zero, CPU


210


updates the cooldown time stored in CPU


210


for the selected temperature. At the end of the cooldown sequence, temperature sensor


240


measures the temperature of exhaust air from drum


14


. This temperature reading is compared to a reference value, preferably 100° F. (37.8° C.). If the temperature is less than the reference temperature, indicating to CPU


210


that the cooldown sequence has actually proceeded too long, CPU


210


subtracts one minute from the next cooldown sequence and stores this value in drying schedule


215


. If, however, the temperature is greater than or equal to the reference temperature, CPU


210


adds one minute. In order to avoid extreme cooldown times, at both the short and long ends, CPU


210


is preferably prohibited from increasing the length of the cooldown time beyond twenty minutes and from decreasing the length below five minutes.





FIG. 3

represents a typical operation of clothes dryer


1


. Specifically, the operation described in

FIG. 3

details the operation of CPU


210


when clothes dryer


1


is operated with regular heat, the wrinkle-free operation and a VERY DRY dryness level after the first ten runs. Initially, a user selects the desired options (Step


302


), i.e. heat level, cycle type and dryness level, and presses start (Step


304


). CPU


210


then reads the expected drying time from drying schedule


215


and shows that number on display


75


(Step


306


). Timer


220


is then started to begin timing the drying cycle and to decrement display


75


through display driving circuit


225


(Step


308


). In Step


310


, CPU


210


begins operation of clothes dryer


1


by rotating drum


14


and initiating the heater according to the selected heat level. Using moisture sensor


230


, CPU


210


measures the dryness level of the articles and compares the level to a reference indicating DAMP DRY (Step


312


). If the DAMP DRY level has not been reached, CPU


210


returns clothes dryer


1


to Step


310


, wherein drum


14


and heater


260


are operated until the DAMP DRY level is reached. If, however, the DAMP DRY level has been reached, CPU


210


reads the duration from the start, as indicated by timer


220


, and compares this value to the number read from the table of dryness schedules


215


corresponding to a regular heat and DAMP DRY moisture level (Step


314


). The table and display


75


are updated in Step


316


by taking one-quarter of the difference between the two numbers and adding the result to each of the values representing the expected drying times for the LESS DRY, NORMAL DRY, MORE DRY and VERY DRY times. Additionally, display driving circuit


225


adjusts display


75


to read the new expected drying time as the estimated drying time remaining. As a result, display


75


initially displays the expected drying time read from drying schedule


215


and counts down until being updated, where it begins to count down again.




After updating the table and display (Step


316


), CPU


210


continues operation of clothes dryer


1


until the LESS DRY threshold is reached (Step


320


). Again, the difference between the duration since the drying operation was begun and the expected drying time corresponding to a regular heat and LESS DRY moisture level is calculated (Step


322


) and the table and display


75


are updated just as in Step


316


, i.e. one-quarter of the calculated difference is added to the expected drying times for regular heat and display


75


is changed to reflect the new expected drying time (Step


324


). Drying the clothes continues (Step


326


) until the NORMAL DRY threshold is reached (Step


328


), where the difference between the expected drying time and the actual duration is again calculated (Step


330


) and the table and display


75


are updated (Step


332


), just as for the previous dryness levels. The same general procedure follows for the MORE DRY dryness level, i.e., continue drying (Step


334


), when MORE DRY threshold is reached (Step


336


), calculate the difference in times (Step


338


), and update the table and display


75


(Step


340


). Again, drying continues (Step


342


) until the VERY DRY threshold is reached (Step


344


), and the difference in times is calculated (Step


346


). But because the articles have now reached the selected dryness level, only the table needs updating (Step


348


).




As the wrinkle-free cycle was initially selected (Step


302


), the cooldown sequence now begins with continued tumbling of drum


14


but no added heat. Again, each of the sense-dry cycles actually includes a cooldown cycle portion. In the wrinkle-free cycle, this portion is simply longer. In any event, the cooldown time is incorporated into the estimated drying time for the particular cycle. However, there would be a designated minimum cooldown time for each cycle. If this minimum amount of time is reached by timer


220


before Step


344


is realized, the timer


220


would be stopped until cooldown (Step


354


) is reached. In any event, CPU


210


causes display driving circuit


225


to show the cooldown time on display


75


and restarts timer


220


, as needed, to time the duration of the cooldown sequence. Cool air is introduced into drum


14


(Step


354


) until the reading from timer


220


equals the cooldown time as indicated by drying schedule


215


(Step


356


). The exhaust temperature is measured by temperature sensor


230


(Step


358


) and compared to 100° F. (37.8° C.) (Step


360


), although the final temperature level may vary in accordance with the invention. If the exhaust air temperature is greater than or equal to 100° F. (37.8° C.), CPU


210


increases the cooldown time for the next cycle by one minute (Step


362


). If, however, the temperature of the exhaust air flow is less than 100° F. (37.8° C.), the cooldown time is decreased by one minute for the next cooldown sequence (Step


364


). However, it must be remembered that, as discussed above, CPU


210


is required to maintain the cooldown time between five and twenty minutes, regardless of sensed temperature. Finally, the tumbling of drum


14


is terminated. At this point, it should be understood that the cool down time could be included in the displayed expected time remaining.




With this arrangement, dryer settings are not limited to those preset at the factory, but rather the settings are automatically customized based on varying environmental conditions, as well as customary user applications and preferences. By continually updating the display, the user is provided with a more accurate end-of-cycle time indication. Because the system is adaptive and learns, further “drying cycle” updates are incorporated into future cycles.




Although described with reference to preferred embodiments of the invention, it should readily understood that various changes and/or modifications could be made to the invention without departing from the spirit thereof. For example, it is possible to provide control panel


22


with a single heat selection to simplify the operations and drying schedule


215


. Additionally, the number of dryness levels may be decreased to further simplify operation, or increased to give greater flexibility to the user. Furthermore, the invention could be modified to actually end the cool down portion of the cycle based solely upon sensing a predetermined temperature for the dryer, regardless of the actually displayed expected drying time. Finally, it is within the scope of this invention to utilize moisture sensor


230


to continually update or adjust moisture monitor


55


to show the current moisture level of the articles. In any event, the invention is only intended to be limited by the scope of the following claims.



Claims
  • 1. A method of controlling a clothes dryer comprising:reading a desired dryness level selected by a user for articles of clothing to be dried in the clothes dryer; establishing a drying cycle at a temperature for the clothes dryer in accordance with a drying schedule which is predetermined, depending upon the selected dryness level; sensing an operational parameter of the drying cycle during the drying cycle; and adjusting the drying schedule, for subsequent drying cycles established for at least the selected dryness level, based upon the sensed operating parameter.
  • 2. The method of claim 1, wherein said sensing step includes detecting a moisture level of articles of clothing contained within the clothes dryer.
  • 3. The method of claim 2, further comprising: determining the drying schedule from an algorithm.
  • 4. The method of claim 2, further comprising: reading the drying schedule from a table of expected drying times for at least one operation temperature and at least one dryness level.
  • 5. The method of claim 4, further comprising: displaying a remaining drying time as read from the table.
  • 6. The method of claim 4, further comprising:determining a drying cycle time required to reach an intermediate dryness level as a sensed moisture level; and calculating a time difference between the drying cycle time required to reach the intermediate sensed moisture level and the expected drying time as read from the table.
  • 7. The method of claim 6, wherein the intermediate dryness level is equal to the selected dryness level.
  • 8. The method of claim 6, further comprising: adding a percentage of the time difference to the expected drying time for subsequent drying cycles.
  • 9. The method of claim 6, further comprising: adjusting the values of expected drying times for each dryness level and operation temperature based upon the sensed moisture levels during the cycle.
  • 10. The method of claim 9, wherein the values of expected drying times are adjusted by respectively adding or subtracting a percentage of the time difference.
  • 11. The method of claim 6, further comprising: adjusting values of expected drying times for the selected dryness level based upon the sensed moisture levels at at least one time during the cycle.
  • 12. The method of claim 1, wherein said drying cycle includes a cooldown step and the sensing of the operational parameter includes measuring a temperature of an exhaust air stream of said clothes dryer.
  • 13. The method of claim 12, further comprising: comparing the temperature of the exhaust air stream to a reference temperature to determine the duration of said cooldown steps of future cycles.
  • 14. The method of claim 13, wherein said adjusting step includes subtracting time from a cooldown segment of the drying schedule if the temperature of the air stream is less than the reference temperature or, in the alternative, adding time to the cooldown segment of the drying schedule if the temperature of the exhaust air stream is not less than the reference temperature.
  • 15. A clothes dryer comprising:an outer cabinet shell; a drum rotatably mounted within said outer cabinet shell, said drum being adapted to receive articles of clothing to be heated and dried therein; a system for sensing an operating parameter associated with the clothes dryer; a control panel, attached to the outer cabinet shell, including at least one temperature selection member, a cycle selection element moveable through a first cycle zone during operation of said clothes dryer, and indicia, representative of said first cycle zone, extending adjacent at least a portion of said cycle selection element on said control panel; a memory including a drying schedule; and means for adjusting said drying schedule during a drying operation of said clothes dryer based on the sensed operating parameter.
  • 16. The clothes dryer according to claim 15, wherein said operating parameter is a moisture level of articles placed in the drum.
  • 17. The clothes dryer according to claim 16, wherein said drying schedule is determined from an algorithm.
  • 18. The clothes dryer according to claim 16, wherein said drying schedule includes a table of expected drying times for at least one dryness level.
  • 19. The clothes dryer according to claim 18, further comprising: a display adapted to visually convey an expected drying time to a user of the clothes dryer.
  • 20. The clothes dryer according to claim 16, wherein said cycle selection element is used to select a desired dryness level for the articles from among different dryness levels shown by said indicia.
  • 21. The clothes dryer according to claim 20, further comprising:a timer adapted to measure a time for a drying cycle; and means for comparing a time required to reach said desired dryness level, as measured by said timer and said sensing system, to an expected drying time.
  • 22. The clothes dryer according to claim 21, further comprising: a display adapted to visually convey said expected drying time to a user of the clothes dryer.
  • 23. The clothes dryer according to claim 21, wherein said comparing means is adapted to compare said expected drying time to said cycle time during said drying cycle.
  • 24. The clothes dryer according to claim 18, wherein said table of expected drying times includes expected drying times for different desired final dryness levels.
  • 25. The clothes dryer according to claim 15, wherein said drying operation includes a cooldown operation and said operating parameter is a temperature of an exhaust air stream of said clothes dryer.
  • 26. The clothes dryer according to claim 25, further comprising:means for comparing the temperature of the exhaust air stream to a reference temperature, and for subtracting time from said drying schedule if the temperature of the exhaust air stream is less than the reference temperature or, in the alternative, adding time to the drying schedule if the temperature of the exhaust air stream is not less than the reference temperature.
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