Patent Application
20130025072
Laundry treating appliances, such as a washing machine, are known to have a configuration where a rotating drum may be provided and defines a treating chamber in which laundry may be placed for treatment. The laundry treating appliance may have a controller that implements a number of user-selectable, pre-programmed cycles of operation. Hot water, cold water, or a mixture thereof along with various treating chemistries may be supplied to the treating chamber in accordance with the cycle of operation.
The invention relates to a laundry treating appliance and method for forming water paths through the laundry by applying water to the top of the laundry and letting the water travel through the laundry, after the forming of the water paths, applying a first detergent solution to the top of the laundry and letting at least some of the first detergent solution follow the water paths to replace the water, with at least some of the replaced water and the first detergent solution forming a first mixture in the tub, forming a second detergent solution from at least some of the first mixture, with the second detergent solution forming a concentration less than the first detergent solution, and applying the second detergent solution to the top of the laundry and letting at least some of the second detergent solution follow the water paths to replace the first detergent solution.
In the drawings:
Washing machines are typically categorized as either a vertical axis washing machine or a horizontal axis washing machine. As used herein, the “vertical axis” washing machine refers to a washing machine having a rotatable drum, perforate or imperforate, that holds fabric items and a clothes mover, such as an agitator, impeller, nutator, and the like within the drum. The clothes mover moves within the drum to impart mechanical energy directly to the clothes or indirectly through wash liquid in the drum. The clothes mover may typically be moved in a reciprocating rotational movement. In some vertical axis washing machines, the drum rotates about a vertical axis generally perpendicular to a surface that supports the washing machine. However, the rotational axis need not be vertical. The drum may rotate about an axis inclined relative to the vertical axis. As used herein, the “horizontal axis” washing machine refers to a washing machine having a rotatable drum, perforated or imperforate, that holds fabric items and washes the fabric items by the fabric items rubbing against one another as the drum rotates. In some horizontal axis washing machines, the drum rotates about a horizontal axis generally parallel to a surface that supports the washing machine. However, the rotational axis need not be horizontal. The drum may rotate about an axis inclined relative to the horizontal axis. In horizontal axis washing machines, the clothes are lifted by the rotating drum and then fall in response to gravity to form a tumbling action. Mechanical energy is imparted to the clothes by the tumbling action formed by the repeated lifting and dropping of the clothes. Vertical axis and horizontal axis machines are best differentiated by the manner in which they impart mechanical energy to the fabric articles. The illustrated exemplary washing machine of
As illustrated in
A rotatable drum 30 having an open top may be disposed within the interior of the housing 14 and may define a treating chamber 32 for treating laundry. An imperforate tub 34 may also be positioned within the housing 14 and may define an interior within which the drum 30 may be positioned. The drum 30 may include a plurality of perforations (not shown), such that liquid may flow between the tub 34 and the drum 30 through the perforations. While the illustrated laundry treating appliance 10 includes both the tub 34 and the drum 30, with the drum 30 defining the laundry treatment chamber 32, it is within the scope of the invention for the laundry treating appliance to include only one receptacle, with the receptacle defining the laundry treatment chamber for receiving the load to be treated.
A clothes mover 38 may be located in the drum 30 to impart mechanical agitation to a load of laundry placed in the drum 30. The drum 30 and the clothes mover 38 may be driven by an electrical motor 40 operably coupled with the drum 30 and clothes mover 38. A clutch assembly 41 may be provided to selectively operably couple the motor 40 with either the drum 30 and/or the clothes mover 38. The clothes mover 38 may be oscillated or rotated about its axis of rotation during a cycle of operation in order to produce high water turbulence effective to wash the load contained within the treating chamber 32. The motor 40 may rotate the drum 30 at various speeds in either rotational direction about an axis of rotation.
A liquid supply system may be provided to liquid, such as water or a combination of water and one or more wash aids, such as detergent, into the treating chamber 32. The liquid supply system may include a water supply configured to supply hot or cold water. The water supply may include a hot water inlet 44 and a cold water inlet 46, a valve assembly, which may include a hot water valve 48, a cold water valve 50, and a diverter valve 55, and various conduits 52, 56, 58. The valves 48, 50 are selectively openable to provide water, such as from a household water supply (not shown) to the conduit 52. The valves 48, 50 may be opened individually or together to provide a mix of hot and cold water at a selected temperature. While the valves 48, 50 and conduit 52 are illustrated exteriorly of the housing 14, it may be understood that these components may be internal to the housing 14.
As illustrated, a detergent dispenser 54 may be fluidly coupled with the conduit 52 through a diverter valve 55 and a first water conduit 56. The detergent dispenser 54 may include means for supplying or mixing detergent to or with water from the first water conduit 56 and may supply such treating liquid to the tub 34. It has been contemplated that water from the first water conduit 56 may also be supplied to the tub 34 through the detergent dispenser 54 without the addition of a detergent. A second water conduit, illustrated as a separate water inlet 58, may also be fluidly coupled with the conduit 52 through the diverter valve 55 such that water may be supplied directly to the treating chamber through the open top of the drum 30. Additionally, the liquid supply system may differ from the configuration shown, such as by inclusion of other valves, conduits, wash aid dispensers, heaters, sensors, such as water level sensors and temperature sensors, and the like, to control the flow of treating liquid through the laundry treating appliance 10 and for the introduction of more than one type of detergent/wash aid.
A liquid recirculation system may be provided for recirculating liquid from the tub 34 into the treating chamber 32. More specifically, a sump 60 may be located in the bottom of the tub 34 and the liquid recirculation system may be configured to recirculate treating liquid from the sump 60 onto the top of a laundry load located in the treating chamber 32. A pump 62 may be housed below the tub 34 and may have an inlet fluidly coupled with the sump 60 and an outlet configured to fluidly couple to either or both a household drain 64 or a recirculation conduit 66. In this configuration, the pump 62 may be used to drain or recirculate wash water in the sump 60. As illustrated, the recirculation conduit 66 may be fluidly coupled with the treating chamber 32 such that it supplies liquid into the open top of the drum 30. The liquid recirculation system may include other types of recirculation systems.
The laundry treating appliance 10 may further include a controller 70 coupled with various working components of the laundry treating appliance 10 to control the operation of the working components. As illustrated in
The controller 70 may be operably coupled with one or more components of the laundry treating appliance 10 for communicating with and/or controlling the operation of the components to complete a cycle of operation. For example, the controller 70 may be coupled with the hot water valve 48, the cold water valve 50, diverter valve 55, and the detergent dispenser 54 for controlling the temperature and flow rate of treating liquid into the treating chamber 32; the pump 62 for controlling the amount of treating liquid in the treating chamber 32 or sump 60; the motor 40 and clutch 41 for controlling the direction and speed of rotation of the drum 30 and/or the clothes mover 38; and the user interface 24 for receiving user selected inputs and communicating information to the user. The controller 70 may also receive input from a temperature sensor 76, such as a thermistor, which may detect the temperature of the treating liquid in the treating chamber 32 and/or the temperature of the treating liquid being supplied to the treating chamber 32. The controller 70 may also receive input from various additional sensors 78, which are known in the art and not shown for simplicity. Non-limiting examples of additional sensors 78 that may be communicably coupled with the controller 70 include: a weight sensor, and a motor torque sensor.
The laundry treating appliance 10 may perform one or more manual or automatic treating cycles or cycle of operation. A common cycle of operation includes a wash phase, a rinse phase, and a spin extraction phase. Other phases for cycles of operation include, but are not limited to, intermediate extraction phases, such as between the wash and rinse phases, and a pre-wash phase preceding the wash phase, and some cycles of operation include only a select one or more of these exemplary phases. Regardless of the phases employed in the cycle of operation, the method described below may relate to an increased chemical action of a detergent or other treating chemistry, which may be supplied into the treating chamber 32 during a cycle of operation.
The previously described laundry treating appliance 10 provides the structure necessary for the implementation of a method of the invention. One embodiment of the method will now be described in terms of the operation of the laundry treating appliance 10.
Generally, in normal operation of the laundry treating appliance 10, a user first selects an appropriate cycle of operation via the user interface 24. Non-limiting examples of cycles of operation include normal, delicate, and heavy-duty. The user-selection may occur prior to the start of the method 100. If a user selects a cycle of operation that does not use treating chemistry such as a rinse only cycle, the method 100 may not be performed for that single cycle of operation. However, if the user selects a cycle of operation that does not exclude the use of a treating chemistry then the controller 70 may execute the method 100.
The method 100 assumes that a user has provided the appropriate detergent, with or without enzyme additives, in the detergent dispenser 54, placed a laundry load within the treating chamber 32, and selected a cycle of operation that includes dispensing the detergent. The method 100 may be initiated automatically when the user closes the lid 28, or at the start of the user-selected cycle of operation. At 102, water may be supplied to the treating chamber 32 through the water inlet 58 and the laundry located within the drum 30 may be wet from the top such that water paths are formed through the laundry load. Such water paths may be formed when the water is applied to the top of the laundry load and allowed to travel through the laundry in response to gravity. As the water travels through the laundry it forms water paths (represented by dots in laundry 110 in
Ideally, the water will completely saturate the laundry load, resulting in an infinite number of paths. Practically, such will not happen for a variety of reasons, such as the laundry is never evenly distributed, which leads to laundry having thicker/deeper portions, which locally require more water to saturate than thinner/shallower portions. The laundry is also rarely comprised of equally absorbent items, resulting in some portions will be more absorbent than others. Even if the laundry were evenly distributed, the differing absorbency would lead to different portions of the laundry having different water paths. The water is also typically not evenly applied to the laundry load. To obtain perfect wetting with the minimal amount of water in a top application, it would be necessary to match the water supplied to the top of each portion of the load with the corresponding absorbency of a vertical section through the laundry load.
To address the practical limitations, the described embodiment takes the approach of wetting the laundry with an amount of liquid that, under ideal conditions, should be sufficient to uniformly wet the laundry and then distributes the water as evenly as possible to increase the likelihood that as many water paths as possible will be formed.
Depending on the particular cycle of operation cold and/or hot water may be supplied to form the water paths. For purposes of this disclosure, it will be presumed that only cold water will be supplied, with the understanding that any combination of hot and cold water may be supplied.
To form the water flow paths, the cold water supplied at 102 may be supplied through the open top of the drum 30 by opening the cold water valve 50 and directing the flow of water through the diverter valve 55 to the water inlet 58. The time period for supplying the cold water or the amount of cold water supplied may be controlled by the controller 70. Alternatively, it has been determined that water amounts for specific loads may be controlled through measuring a water column formed in the sump 60 and that the addition of water may be stopped when it has been determined that a minimal amount of water has reached the sump 60. Water amounts may vary by load type and for a standard AHAM cotton load may be 125-200 weight percent of the dry fabric weight. By way of non-limiting example, cold water in the amount of 8 liters may be supplied during 102 for load having a weight of 3.6 Kg, and comprising an AHAM standardized load containing towels, pillowcases, and bedsheet fabric types. Such a volume of water may be sufficient to saturate the laundry in the treating chamber 32, assuming ideal conditions. To more evenly distribute the incoming water and aid in the formation of more water paths through the laundry load, the drum 30 may be rotated while the water is being supplied from the water inlet 58 during 102, which will tend to compensate for uneven dispersing of water from the water inlet 58.
It has been contemplated that the laundry may be moved by the clothes mover 38 during 102 to aid in forming the water paths. This movement of the laundry by the clothes mover 38 may occur while the water may be supplied from the water inlet 58, after the water has been supplied from the water inlet 58, or both during and after the water has been supplied. It has also been contemplated that during 102, some of the water may travel through the laundry load to the tub 34. Water in the tub 34 may be recirculated by the pump 62 through the recirculation conduit 66 such that it may be sprayed back on top of the laundry to aid in forming the water paths. During this recirculation, the clothes mover 38 may be driven by the motor 40 such that the laundry may be moved during this recirculation. Thus, a non-limiting example of 102 may include an initial supply of 8 liters of water while the drum 30 is rotating, followed by a driving the clothes mover 38 and/or the drum 30 for a predetermined time, such as a minute or so, which is followed by water in the tub 34 being recirculated for a predetermined time, such as 18 seconds or so, while the drum 30 is being rotated. Further, the drum 30 may be rotated after the water is supplied to aid in the distribution of the water throughout the load.
After the water paths are formed in 102, a first detergent solution may be applied to the top of the laundry at 104. This may be accomplished by opening the cold water valve 50 and directing the flow of water through the diverter valve 55 to the water conduit 56 and the detergent dispenser 54. The time period for supplying the cold water or the amount of cold water supplied may be controlled by the controller 70. The volume of water supplied to the detergent dispenser 54 may be sufficient to mix with the detergent in the detergent dispenser 54 and carry the detergent to the tub 34. When the water and detergent enter the tub 34 they may mix with any water supplied in 102, which may be located in the tub 34, to form a first detergent solution.
Such a first detergent solution may be applied to the top of the laundry load by activating the pump 62 such that the first detergent solution may be supplied through the recirculation conduit 66 and be sprayed on top of the laundry. It is contemplated that the drum 30 may be rotating while the first detergent solution may be applied to the top of the laundry, after the first detergent solution has been applied, or both during and after the first detergent solution has been applied. Further, it has been contemplated that the laundry may be moved by the clothes mover 38 during 104 to mechanically agitate the laundry. This movement of the laundry by the clothes mover 38 may occur while the first detergent solution may be applied to the top of the laundry, after the first detergent solution has been applied, or both during and after the first detergent solution may be applied. Such movement of the drum 30 and/or clothes mover 38 may aid in the distribution of the first detergent solution both while the first detergent solution may be applied and after. A more uniform detergent distribution may promote more effective and uniform cleaning
The first detergent solution (represented by the plus signs in
It should be noted that the detergent solution will have a lower surface tension than the water because of the wetting agents, such as surfactants, typically found in detergents. The lower surface tension will more readily provide the detergent solution with the ability to spread out within the laundry (
The amount of water supplied to the detergent dispenser 54 at 104 may be limited to reduce the amount of the first detergent solution that travels completely through the laundry back to the tub 34 to minimize the wasting of water. The amount of water supplied to the detergent dispenser 54 at 104 may be selected to have an increased concentration of the detergent in the first detergent solution. This is further beneficial in that, within the practical limits of the clothes washer environment, the greater the concentration of the detergent solution, the better the cleaning action is. By way of non-limiting example, water in a range of 2 to 4 liters may be supplied to the tub 34 through the detergent dispenser 54 during 104. As described, the volume of water supplied during the forming of the water paths in 102 is greater than the volume of water supplied during the forming of the first detergent solution in 104.
Thus, a non-limiting example of 104 may include an initial supply of 3 liters of water to the detergent dispenser 54, which enters the tub to form a first detergent solution, and recirculating the first detergent solution onto the laundry while the drum 30 rotates, followed by a driving the clothes mover 38 and/or the drum 30, which may be conducted for a predetermined time, such as one minute. At this point, it is contemplated that the first mixture in the tub 34 may be recirculated by the pump 62 through the recirculation conduit 66 such that it may be sprayed back on top of the laundry. It is also contemplated that such a recirculation may occur during the period of driving the clothes mover 38 and/or drum 30, which may follow the application of the first detergent solution.
At 106, a second detergent solution may be formed in the tub 34 with the second detergent solution forming a concentration less than the first detergent solution. The second detergent solution may be formed from at least some of the first mixture, additional water from the water supply, and additional detergent if any residual detergent remains in the detergent dispenser 54. Forming the second detergent solution may be accomplished by opening the cold water valve 50 and directing the flow of water through the diverter valve 55 to the water conduit 56 and the detergent dispenser 54. The time period for supplying the cold water or the amount of cold water supplied may be controlled by the controller 70. The volume of water supplied to the detergent dispenser 54 may be sufficient to mix with residual detergent in the detergent dispenser 54 and carry the residual detergent to the tub 34. When the water and residual detergent enter the tub 34 they may mix with the first mixture formed in 104, which may be located in the tub 34, to form a second detergent solution.
In the context of this embodiment, the second detergent solution is formed to ensure that all of the detergent in the dispenser has been removed. While it is generally preferred to maintain the concentration of detergent as high as possible, and the addition of more water will tend to dilute the first detergent solution, it has been found that a second supply of water to form the second detergent solution may introduce new detergent into the second detergent solution to minimize the reduction, if any, of the detergent concentration for the second detergent solution. Thus, only enough water is added to flush out any remaining detergent, which will serve to maximize the detergent concentration in the second detergent solution. By way of non-limiting example, water in a range of 1 to 3 liters may be supplied to the tub 34 through the detergent dispenser 54 during 106. The total water amount in the washing machine 10 after the addition at 106 may be significantly lower than current total water volumes in most conventional washers and enables concentrated washing.
At 108, the second detergent solution may be applied to the top of the laundry and at least some of the second detergent may be allowed to follow the water paths to replace the first detergent solution. Such a second detergent solution may be applied to the top of the laundry load by activating the pump 62 such that the second detergent solution may be supplied through the recirculation conduit 66 and be sprayed on top of the laundry. It is contemplated that the drum 30 may be rotating while the second detergent solution may be applied to the top of the laundry, after the second detergent solution has been applied, or both during and after the second detergent solution may be applied. Further, it has been contemplated that the laundry may be moved by the clothes mover 38 during 108. This movement of the laundry by the clothes mover 38 may occur while the second detergent solution may be applied to the top of the laundry, after the second detergent solution has been applied, or both during and after the second detergent solution may be applied. Such movement of the drum 30 and/or clothes mover 38 may aid in the distribution of the second detergent solution both while the second detergent may be applied and after. At least some of the second detergent solution may follow the water paths in the laundry and replace the first detergent solution such that the first detergent solution enters the tub 34.
It is contemplated that after such applying of the second detergent solution in 108, the laundry may be allowed to soak for a predetermined time as most of the detergent is now residing in the laundry load. The soaking will give the detergent more time to chemically react with the soils on the laundry.
It is contemplated that the volume of the second detergent solution may be sufficient such that during the soaking at least some of the second detergent solution travels through the laundry and into the tub 34. It is further contemplated that at least some of the second detergent solution may be recirculated back onto the laundry during the soaking. During such recirculation, the laundry may be moved by the clothes mover 39 and/or the drum 30 may be rotated. After such recirculation, the laundry may continue to soak. Placing such a recirculation partway through the soak allows any of the second detergent solution that previously traveled into the tub 34 to be recirculated back on top of the laundry, which may increase the amount of chemistry on the laundry load and thus increase the chemical action applied to the laundry by the detergent. It is believed that the second detergent solution, which made its way to the tub 34, will be more chemically active than the second detergent solution residing in the laundry load. Thus, it is desirable to recirculate the more chemically active solution onto the laundry. It is also contemplated that the soak may also be preceded by a recirculation of the liquid in the tub 34.
After the second detergent solution may be applied and after any soaking period, the cycle of operation may then continue with a main wash phase. Such a main wash phase may include supplying water to the tub 34 in an amount to at least partially submerge the laundry to form a wash liquid and agitating the laundry in the wash liquid. This may include opening either or both of the valves 48, 50 and directing the flow of water through the diverter valve 55 to the water inlet 58. The time period for supplying the wash water or the amount of wash water supplied may be controlled by the controller 70. The amount of water added is normally sufficient for the liquid level in the tub to rise above the bottom of the basket to submerge at least some of the laundry.
The wash phase may be followed by one or more rinse phases. Such a rinse phase may include draining any liquid from the tub 34 and supplying rinse water to the laundry. The draining may be accomplished by operating the pump 62 such that it directs the liquid in the tub 34 to the household drain 64. Supplying the rinse water may include opening either or both of the valves 48, 50 and directing the flow of water through the diverter valve 55 to the water inlet 58. The time period for supplying the rinse water or the amount of rinse water supplied may be controlled by the controller 70.
The one or more rinse phases may be followed by an extraction phase wherein the rinse water may be drained from the tub 34, by operating the pump 62 such that it directs the liquid in the tub 34 to the household drain 64, and the drum 30 may be rotated by the motor 40 to centrifugally remove rinse water from the laundry, which may also be drained. The method 100 may end when the cycle of operation ends, or when detergent supply for the cycle of operation ends.
The invention described herein offers increased chemical action of the supplied detergent and additional advantages unrelated to the increased chemical action. The above invention balances using water to uniformly apply a high concentration detergent to laundry while maintaining the high concentration. Enough water is used to dispense and disperse the detergent but not reduce its high concentration. Detergent chemical adhesion is strong on dry fabrics and once the detergent is attached thereto it may be hard to transport the detergent to uniformly distribute it. Direct dispensing of a detergent solution on dry fabrics may also lead to the detergent penetrating into an interior of the fibers and due to the above described strong adhesion may make movement out of the fiber interior difficult such that transport of the detergent to different stains may decrease. The water paths formed in the inventive method provide a transport medium where the detergent remains dissolved and may more easily move on the laundry allowing for greater detergent uniformity and hence more uniform and better cleaning. The invention uses less water than other contemporary washing machines and achieves a greater distribution of the highly concentrated detergent, which results in an increased chemical action of the detergent because more detergent remains on the laundry. Advantageously, the greater distribution may be accomplished with less liquid than contemporary methods. In many cases, the distribution may be at a higher concentration because less liquid is used. Further, this wider distribution of a higher concentration of detergent solution has an increased chemical action and improves the removal of the soils because more chemistry gets to more of the laundry. The dispensed detergent solution may be permitted to sit and soak into the soils. The minimized amount of water significantly reduces the overall water requirements, and consequently, the electric energy required for heating the water.
While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. Reasonable variation and modification are possible within the scope of the forgoing disclosure and drawings without departing from the spirit of the invention which is defined in the appended claims.
