Patent Publication Number: US-2006010611-A1

Title: Washing machine water level controller

Description:
FIELD OF THE INVENTION  
      This invention relates generally to washing machines and specifically to predetermined or preset rinse depth levels.  
     CROSS-REFERENCE TO RELATED APPLICATIONS  
      N/A  
     STATEMENT REGARDING FEDERALLY FUNDED RESEARCH  
      This invention was not made under contract with an agency of the US Government, nor by any agency of the US Government.  
     BACKGROUND OF THE INVENTION  
      Prior to the invention of a washing machine, clothes were washed in streams and pounded with rocks in order to loosen dirt and oils from the woven fibers. Cleaning laundry moved from the stream to large tubs where laundry was left to soak. It was then rubbed over corrugated washboards and the water was wrung out by hand.  
      The evolution of the washing machine includes hand-operated machines that gave way to steam engines and gasoline motors to drive the machinery. Electric-powered washing machines were introduced in the early 1900&#39;s. In addition, electric washing machines became more popular as in-door plumbing and electricity was widely available in households.  
      The washing machine is one of the more complicated appliances in the home. Various washing machines offer several settings for washing many types and quantities of materials. Its primary functions are to wash, rinse and partially dry laundry by mechanical extraction of the trapped water.  
      The washing machine holds an outer tub and an inner perforated basket that holds the laundry. After detergent is added to the laundry, the operator selects the desired settings for the overall water level, water temperature, and the duration and speed of the wash and rinse cycles. Typically, washing machines offer three settings of low, medium, and high water levels that are maintained through out all cycles. Dark and light colored laundry are divided and washed separately to eliminate the possibility of a color fade from darker fabrics on to lighter fabrics. Whites and cottons are best cleaned in hot water, while fragile materials require cooler temperatures and slower speeds. A timer within the control panel is used to regulate the wash, rinse and water extraction cycles. Of interest to this application is that the timer controls the length of time the pump is activated. A greater length of time provides a deeper water level. The timer also controls the duration of the cycles.  
      Currently, many parts of the United States of America are facing varying degrees of drought that have raised the cost of water and many local governments have restricted the days and hours that water may be used on lawns and gardens. Households may need to use cost effective and easily administered alternatives to control the water use by appliances inside their homes in order to save money.  
      Various items of prior art may be considered that address the operation and cycles of the washing machine.  
      U.S. Pat. No. 6,360,567 issued Mar. 26, 2002 to Lu for WASHING MACHINE ADAPTED TO BE SUPPLIED WITH DIFFERENT LEVELS OF WATER DURING A WASHING OPERATION teaches what seems to be no less than three wash/rinse cycles, and that during the first such operations the water level may be reduced. The &#39;567 patent is not at all clear what the relationship between “wash” water and “rinse” water may be in the &#39;567 patent. It may not deal with any difference in water level between a “wash” cycle and a following “rinse” cycle but rather may deal with three washes and three rinses, only varying the level compared between rinses, not rinses in comparison to washes.  
      U.S. Pat. No. 6,029,298 issued Feb. 29, 2000 to Dausch et al for SYSTEM AND METHOD FOR DETERMINING A LIQUID LEVEL SETTING IN A WASHING MACHINE teaches a complex fuzzy logic algorithm which compensates for differing types of materials in the wash load.  
      U.S. Pat. No. 5,987,679 issued Nov. 23, 1999 to Won for WATER LEVEL SENSING METHOD AND APPARATUS IN WASHING MACHINE determines a variable water level by sensing the difference between dry and wet laundry.  
      U.S. Pat. No. 5,768,729 issued Jun. 23, 1998 to Cracraft for ADAPTIVE FILL CONTROL FOR AN AUTOMATIC WASHER is similar to the &#39;298 patent in using a complex fuzzy logic process to determine laundry materials and compensate for the differing absorptions of such materials.  
      U.S. Pat. No. 5,737,790 issued Apr. 14, 1998 to Badger et al for RINSING PROCEDURE FOR AUTOMATIC WASHING MACHINE teaches a comparison of rinse cycle water use, by teaching that a rinse may be replaced with a series of spray rinses. The amount of water used is sensed in a first spray rinse cycle, then a proportion of that amount is used in later spray rinses. Thus a proportion of wash cycle water to rinse cycle water is never determined.  
      U.S. Pat. No. 3,030,789 issued Apr. 24, 1962 to Rothenberger for AUTOMATIC CLOTHES WASHING MACHINE teaches a machine that supplies water throughout the wash cycle according to a simple time dependency.  
      It would be advantageous to have a device providing an easy and inexpensive retrofit to an existing washer that reduces the rinse cycle water level to wash cycle water ratio with a control indicating a choice of reductions.  
     SUMMARY OF THE INVENTION  
      General Summary  
      The invention revolves around altering the rinse cycle water level. The normal rinse cycle water level is changed to a different rinse cycle water level: there are two different rinse cycle water levels: a default level normally built into a washing machine and a new level (based upon the invention) which is a fraction of the normal level. Thus the machine will have at least three water levels: a first water level (a wash level), a second water level (rinse) and a third water level (rinse level based upon use of the invention water level instead of the second water level).  
      The invention comprises a microprocessor based electronic circuitry device that limits rinse water amounts to a fraction of wash cycle amounts. The device may be wired inside the front panel of the normal (factory) “top loading” automatic clothes washer or a “front loading” automatic clothes washer. Power for a micro-controller is supplied by a low voltage power supply. Interfaces exist to the water valves and timer motor from the micro-controller. The retrofitted on original equipment micro-controller commands the hot and cold valves to start filling the tub and measures the analog water level input from the water level sensor. This number is stored in the micro-controller memory as a “wash water level” during a first cycle (wash cycle). Normally, a second water level would be used for the rinse level If the Water Saver Control (including Disable) switch is enabled by an operator the “Wash Water Level” is divided by an operator selectable percentage of the wash or first rinse cycle, providing a new third “Rinse Water Level” (in the rinse cycle) that is one half the normal rinse level, or another selected fractional amount. Thus a third water level may be an option for the user of the machine: instead of the normal second cycle water level, a third, fractional water level may be used.  
      Summary in Reference to Claims  
      It is one aspect, advantage, embodiment and objective of the present invention to provide a washing machine water level controller comprising an over-ride circuit operatively connected to a cycle control circuit of a washing machine. The over-ride circuit having a timer operatively connected to the operation of the cycle control circuit of the washing machine, a monitoring circuit monitoring a first cycle of the washing machine having a first wash water level, a reduction circuit calculating the selected preset percentage (i.e. one half) of the water level of the first (wash) water level the over-ride circuit operatively connected to over-ride, a second (rinse) water level of the washing machine (the second water level being a “default” rinse water level, perhaps the same water level as the first water level used during the rinse cycle) but the over-ride circuit permitting the washing machine to fill to only a third (rinse) water level for use during the rinse cycle, the third rinse water level being a fraction of the “normal” second rinse water level. The reduction circuit calculating fractions of less than one selected from the group consisting of 1/10, 2/10, 3/10, 4/10, 5/10, 6/10, 7/10, 8/10, 9/10, ¼, or ¾, or another fractional amount of water, and switches on the front panel selected from the group consisting of analog, digital, mechanical, slider, toggle, multi-positioning, button, and touch panel.  
      It is another aspect, advantage, embodiment and objective of the present invention to provide a washing machine water level controller comprising a mechanical over-ride of a first wash water level, the mechanical over-ride of a second (default rinse) water level of the washing machine, the mechanical over-ride to a third water level (a different rinse water level) of the washing machine, the mechanical reduction calculating fractions of less than one selected from the group consisting of 1/10, 2/10, 3/10, 4/10, 5/10, 6/10, 7/10, 8/10, 9/10, ¼, or ¾, or another fractional amount, and switches on the front panel selected from the group consisting of analog, digital, mechanical, slider, toggle, multi-positioning, button, and touch panel.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller comprising: an over-ride circuit operatively connected to a cycle control circuit of a washing machine, a timer of the circuitry operatively connected to the operation of the cycle control circuit of the washing machine, a monitoring circuit monitoring a first cycle of the washing machine having a first wash water level, a reduction circuit calculating a fraction of the water level of the first wash water level, the over-ride circuit operatively connected to over-ride a second rinse water level of the washing machine, the over-ride circuit permitting the washing machine to fill to only a third (rinse) cycle water level, the third rinse water level being the fraction of the second rinse water level.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller further comprising a reduction circuit calculating fractions of less than one selected from the group consisting of 1/10, 2/10, 3/10, 4/10, 5/10, 6/10, 7/10, 8/10, 9/10, ¼, or ¾.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller further comprising switches on the front panel selected from the group consisting of analog, digital, mechanical, slider, toggle, multi-positioning, button, and touch panel.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller further comprising the mechanical over-ride of a second rinse water level of the washing machine.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller further comprising the mechanical over-ride to a third rinse water level of the washing machine.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller wherein the calculation of the fractional water level is performed on the basis of fill time during which the water valves are open.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller wherein the selected fraction comprises one member selected from the group consisting of ⅛, 1/16, 1/32, 1/64, ⅓, ⅔, ⅜, ⅝ and ⅞.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller wherein the selected fraction is determined by an analog input device operated by the user.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a washing machine level controller wherein the analog input device is a potentiometer.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a method of washing clothing in an automatic washing machine, the method comprising the steps of: a) monitoring a first cycle of the washing machine having a first water level, b) calculating a selected fraction of the water level of the first water level, c) permitting the washing machine to fill to only a third water level, the third water level being the selected fraction of the second water level.  
      It is therefore another aspect, advantage, objective and embodiment of the present invention to provide a method wherein the selected fraction comprises one member selected from the group consisting of: 1/10, 2/10, 3/10, 4/10, 5/10, 6/10, 7/10, 8/10, 9/10, ¾, ⅛, 1/16, 1/32, 1/64, ⅓, ⅔, ⅜, ⅝ and ⅞. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a block diagram washing machine water saver.  
       FIG. 2  is a cross sectional view of a washing machine tub.  
       FIG. 3  is a cross sectional view of a washing machine tub with dry laundry.  
       FIG. 4  is a cross sectional view of a washing machine tub with wet laundry.  
       FIG. 5  is a cross sectional view of a washing machine tub with optional water levels.  
       FIG. 6  is a block diagram of the control flow of the present invention and the user control of the present invention. 
    
    
     INDEX TO REFERENCES NUMBERS  
     
         
           10  Low Voltage Power Supply, for example DIGIKEY©/T309-P6P-ND  
           11  Water Level Sensor (Amplified Pressure Sensor)-FUJIKURA© XFPMC-025KPG  
           12  Isolation and Logic Level Conversion  
           13  Micro-controller—PIC18C67X or equivalent  
           14  Isolation and Timer Motor Drive  
           15  Hot and Cold Water Valve Isolator and Driver  
           16  Hot and Cold Water Valves  
           17  Cycle Position Switch From Timer  
           18  Timer Enable Switch  
           19  Existing Mechanical Water Level Switch  
           20  Analog Water Level  
           21  Water Saver Control Switch on Front Panel  
           200  Outer basket  
           201  Inner perforated basket  
           202  Center area volume  
           203  Low level water setting  
           204  Medium level water setting  
           205  High level water setting  
           300  Dry non-compact laundry  
           400  Wet compact laundry after centrifugal water extraction  
           500  Normal rinse level (second level)  
           501  Fractional rinse level of invention (third level)  
           602  Cycle controller  
           604  Timer  
           606  Washing machine  
           608  User input device  
           610  Monitor  
           612  Reduction circuit  
           614  Over-ride circuit  
       
    
     DETAILED DESCRIPTION  
      In the presently preferred embodiment and best mode presently contemplated for carrying out the invention a washing machine water level controller may utilize a microprocessor based electronic system that automatically reduces the amount of water used for the rinse cycle of either a “top loading” automatic clothes washer or a “front loading” automatic clothes washer. Switches on the front panel may be selected from the group consisting of analog, digital, mechanical, slider, toggle, multi-positioning, button, and touch panel.  
      The device embodiment of the invention is wired inside the front panel of the standard “top loading” automatic clothes washer or a “front loading” automatic clothes washer. The device embodiment of the invention may be a retrofit or original equipment provided by the manufacturer.  
      The electrical design of the controller follows in  FIG. 1 .  
      All electrical interfaces with a Micro-controller  13  are Logic Level  12  and will be optically isolated from a 115 VAC line. An alternative micro-controller device of a similar nature may be used. A 5 VDC current to the Micro-controller  13  is supplied by a Low Voltage Power Supply  10 , as described in  FIG. 1 , supplied by DIGIKEY or other manufacturer. The interfaces to water valves  15  and timer motor  14  are isolated from the 115 VAC line, and may look like one TTL load to the Micro-controller  13 .  
      At the initial operation of the washing machine, a Cycle Position Sensor  17  senses that a Timer  14  is in a first cycle wash and the Timer Enable Switch  18  (machine start) is engaged. With the machine in a normal (factory) wash cycle, the Micro-controller  13  commands a Hot and Cold Water Valves  16  to start filling a washtub. The Micro-controller  13  monitors an Existing Mechanical Water Level Switch  19 . When the Existing Mechanical Water Level Switch  19  indicates full it commands the Hot and Cold Water Valves  16  to stop filling the washtub, and confirms a Tub Full internal electronic indication. At the Tub Full indication a Timer Motor Drive  14  is engaged. Additionally at the Tub Full, measurements of an Analog Water Lever  20  from a Water Level Sensor  11  are read and converted by the microprocessor and the microprocessor stores this number in its memory as “Wash Water Level” of the first cycle. The Water Level Sensor  11  may be provided by FUJIKURA or other manufacturer.  
      At the start of the second cycle (rinse cycle), as determined by the Cycle Position Switch  17  for the timer, the Micro-controller  13  checks the position of a Water Saver Control/Disable Switch  21 . If it is in a Disable Mode, it commands the Hot and Cold Water Valves  16  to start filling the washtub. In addition, the Micro-controller  13  checks the position of a Water Saver Control Switch  21 . If it is in a Disable Mode, it commands the Hot and Cold Water Valves  16  to stop filling the washtub when the Existing Mechanical Water Level  19  switch indicates “full”, Tub Full. At the Tub Full indication the Micro-controller  13  engages the Timer Motor Drive  14 . The Micro-controller  13  checks the position of the Water Saver Disable Switch  21  and if it is in an enable mode, it commands the Hot and Cold Water Valves  15  to start filling the washtub. Thus the user may have a selection as simple as “Rinse Water Saver YES” or “Rinse Water Saver NO.” Or the user as discussed in regard to other embodiments, may have a choice of the fractional reduction and savings.  
      As the Micro-controller  13  is performing the above functions, it checks the position of the Water Saver Control Switch  21 . A reduction circuit, within the Micro-controller  13 , sensing an enable mode multiplies the “Wash Water Lever” (first cycle) by the fraction selected by the Control Switch and provides an appropriate “Rinse Water Level”. Upon checking the position of the Water Saver Control Switch  13  for an enable mode, it compares the Analog Water Level  20  to the “Rinse Water Level”. If the Analog Water Level  20  is greater than or equal to the “Rinse Water Level”, the Micro-controller  13  commands the Hot and Cold Water Valves  16  to stop filling the washtub, with the internal electronic indication of “Tub Full”. At “Tub Full”, the Timer Motor Drive  14  is engaged.  
      An alternative embodiment may configure the reduction circuit to calculate fractions less than a whole number selected from the group consisting of 1/10, 2/10, 3/10, 4/10, 5/10, 6/10, 7/10, 8/10, 9/10, ¼, or ¾ thereby offering the operator more options for water levels and savings in dollars and water used. Thus the third water level (water saving rinse), as a fraction of the second (normal rinse) water level, may be adjusted.  
      Alternative embodiments may include a mechanical means to adjust all water levels used in the washing machine. This may increase the inventions use to consumers in areas where there may be an extreme scarcity of water and circuitry is not employed in a locally produced washing machine.  
       FIG. 2  is a cross sectional view of a washing machine tub. The standard washing machine utilizes an outer tub  200  with an inner perforated basket  201 . Generally, three water levels are used in a wash (first cycle) and rinse (second cycle) that fills into a center area  202  of the inner perforated basket  201 . A low  203 , medium  204 , and high  205  water levels are possible options an operator may choose on a front panel of the washing machine. An operator choosing the low  203 , medium  204 , or high  205  water level setting for a first cycle (wash) is obligated to accept the same water level for all subsequent rinse cycles, in the prior art, with the only option being manually resetting the setting during the cycle. The present invention, however, obviates that necessity.  
       FIG. 3  is a cross sectional view of a washing machine tub with dry laundry. The dry condition of laundry  300  fills the inner perforated basket  201  of the washing machine. An operator may or may not perceive the amount or density of the laundry  300  prior to its water saturation during a first cycle (wash).  
       FIG. 4  is a cross sectional view of a washing machine tub with wet laundry. A centrifuge (in the form of an inner basket) is the common means of draining water from the washtub. As the inner perforated basket  201  spins the centrifugal action forces the water and laundry to the outside edge of the inner perforated basket  201 . During this spin cycle, water may be sprayed from an area around the upper edge of the inner perforated basket  201  that may help to pull any remaining detergent out of laundry  400  as the inner perforated basket  201  spins, providing an extra rinse. The remaining water may be pulled out of the laundry through the perforated sides of the inner basket leaving damp laundry  400 . In this damp condition, the laundry has lost a fluffy density that it may have held prior to the first cycle (wash) and before water saturation. The compressed nature of the water-saturated laundry that occurs during the first cycle (a wash) may allow less water to be used during the second cycle (a rinse) towards completing the task of washing, draining soapy water, rinsing and culminating with damp laundry.  
       FIG. 5  is a cross sectional view of a washing machine tub with optional water levels. Ref.  500  shows a normal rinse water level of a washing machine tub and  501  represents a fractional water level a washing machine tub.  
       FIG. 6  is a block diagram of the control flow of the present invention and the user control of the present invention. Cycle controller  602  comprises a washing machine water level controller having a timer  604  operatively connected to the operation of the cycle control circuit of the washing machine. By means of timer  604 , cycle controller  602  controls operations of the washing machine, for example, the length of time a valve is open to admit water, length of a spin cycle and the like. Controller  602  may also measure water levels inside the washing machine  606  to determine when proper water levels are achieved.  
      Over-ride circuit  614  operatively connected to the cycle control circuit  602  of the washing machine  606  may implement the invention. Monitoring circuit  610  monitors a first cycle of the washing machine having a first water level, the first cycle presumably being a wash cycle, and thus the first water level being a “wash” water level.  
      Reduction circuit  612  receives data from monitor  610  and then calculates a selected fraction of the water level of the first water level. The selected fraction of the water level may be selected by an analog or digital user input device  608  located upon the front of the machine. Over-ride  614  is operatively connected to over-ride a second water level of the washing machine, the second water level may correspond to a rinse cycle water level, commonly 100% of the first water level used in the wash cycle.  
      The over-ride  614  permits the washing machine  606  to fill to only a third water level, which is the selected fraction of the second water level, thus saving water, energy and money.  
      If a family of four people were to complete five loads of laundry on a weekly basis using a washing machine with a forty-four gallon capacity wash/rinse tub, and using the calculations offered by the inventor for saving water during the rinse (second) cycle we may see the following savings:  
      At forty-four gallons of water used per rinse cycle, divided by two (savings of 50%), 22 gallons is saved per cycle. The resulting energy savings per load may be 11 kWh, in regions in which clean water requires 0.5 kWh to produce.  
      At fifty-five gallons water used per rinse cycle divided by 2 (assuming one half is saved) equals 27.5 gallons saved with an energy savings per load of 13.75 kWh, in regions of high elevation in which each gallon of clean water requires 0.5 kWh to produce. Under present testing, it seems likely that 27.5 gallons may not be the maximum savings: amounts up to 44 gallons per cycle may be savable, with a consequent increase in the energy savings.  
      Assuming one million families, at only 11 kWh, the energy savings for a single use of each machine (for a family of four, a mere day or two of ordinary clothing usage) means an energy savings of 11 gigawatthours of energy, 22 million gallons of water, and a cost savings of millions of dollars. (In terms of costs, the financial cost per gallon reprocessed is known to each water board for its own operations.)  
      Some modern washing machines allow two rinse cycles in one overall use cycle of the machine. Differential amounts in additional rinse cycles may be provided. For example, in alternative embodiments, the invention may allow the washing machine to use the normal default water level for one rinse cycle but use the fractional amount for another cycle, or may use the fractional water level more than once (multiplying overall savings) or may even allow more than one fractional water level to be selected. As an example, a user of a machine offering multiple rinses, having an embodiment installed which allows selection of multiple fractions of the wash cycle water level, might well select a rinse water level of 75% of normal (or 75% of the wash cycle water level) and a second rinse water level of only 50% of the normal (or 50% of the wash cycle water level).  
      The disclosure is provided to allow practice of the invention by those skilled in the art without undue experimentation, including the best mode presently contemplated and the presently preferred embodiment. Nothing in this disclosure is to be taken to limit the scope of the invention, which is susceptible to numerous alterations, equivalents and substitutions without departing from the scope and spirit of the invention. The scope of the invention is to be understood from the claims accompanying this application.