Patent Publication Number: US-11661699-B2

Title: Low pressure laundry treating appliance

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 17/014,033, filed on Sep. 8, 2020, now U.S. Pat. No. 11,242,646, issued Feb. 8, 2022, which is a continuation of U.S. patent application Ser. No. 16/288,665 filed Feb. 28, 2019, now U.S. Pat. No. 10,816,266, issued Oct. 27, 2020, which claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 62/724,917, filed Aug. 30, 2018, entitled “LOW PRESSURE LAUNDRY TREATING APPLIANCE,” all of which are herein incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     Laundry treating appliances, such as clothes washers, clothes dryers, refreshers, and non-aqueous systems, can have a configuration based on a rotating drum that defines a treating chamber having an access opening through which laundry items are placed in the treating chamber for treating. The laundry treating appliance can have a controller that implements a number of pre-programmed cycles of operation having one or more operating parameters. 
     In some applications, the treating chamber can be a low pressure chamber for enabling and promoting evaporation of water from laundry items. Differing conditions, non-limiting examples of which can include pressure differences and temperature differences, between an area within the treating chamber and an area outside of the treating chamber, or generally between two areas within the laundry treating appliance, can contribute to evaporation of water from laundry items. 
     Systems or assemblies for water reclamation or water recycling can be employed to remove contaminants from a used liquid and reclaim purified liquid that can then be stored or re-used as desired. One common method for reclaiming or recycling water is through vapor compression distillation. In a vapor compression distillation process, influent liquid is brought to the boiling point to effect evaporation. During evaporation, the water is converted to water vapor, while contaminants present in the influent liquid are left behind and can be collected and removed from the assembly. The water vapor is compressed, then moves to a condenser, where it condenses at a higher temperature than the evaporation temperature to allow the energy of condensation to be used for evaporating more water. The condensed effluent distillate can be output from the water reclaiming assembly to be stored or re-used. 
     BRIEF SUMMARY 
     In one aspect, the disclosure herein relates to a laundry treating appliance for treating laundry according to an automatic cycle of operation, the laundry treating appliance has a drum assembly with an outer drum defining an outer drum interior. The outer drum has an outer surface with an infrared absorbing coating and an infrared heater connected with the outer surface. The drum assembly also has an inner drum located within the outer drum interior. The inner drum at least partially defines a treating chamber having an access opening, and the inner drum is spaced from the outer drum to define an interstitial space. The laundry treating appliance further has a closure selectively closing the access opening, a vacuum pump fluidly coupled to the interstitial space, and a cooling assembly fluidly coupled to the vacuum pump 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG.  1    is a perspective view of a laundry treating appliance in the form of a combination washer/dryer according to an aspect of the disclosure herein. 
         FIG.  2    is an exploded view of a tub and drum assembly with a vent and drain system for the laundry treating appliance of  FIG.  1   . 
         FIG.  3    is a schematic of the combination washer/dryer including a motor assembly. 
         FIG.  4    is an exploded view of the motor assembly of  FIG.  3    according to an aspect of the disclosure herein. 
         FIG.  5    is an assembled cross-sectional view of the motor assembly from  FIG.  4   . 
         FIG.  6    is an assembled perspective view of the vent and drain system of  FIG.  2    according to an aspect of the disclosure herein. 
         FIG.  7    is an assembled cross-sectional perspective view of the combination washer/dryer of  FIG.  1   . 
         FIG.  7   a    is the same assembled cross-sectional perspective view of the combination washer/dryer of  FIG.  7    with some of the 3-D lines removed for clarity. 
         FIG.  8    is a schematic view of a laundry treating appliance in the form of a dryer according to another aspect of the disclosure herein. 
         FIG.  9    is a perspective rear view of the dryer from  FIG.  8    according to an aspect of the disclosure herein. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of the present disclosure relate to a laundry treating appliance having a drum with an inner and outer wall that utilizes a vacuum pump to create a negative pressure between the inner and outer walls to enable and promote evaporation, including flash evaporation, during a drying cycle. Flash evaporation is an extremely high rate of evaporation that can occur when water suddenly finds itself in a condition that is above the boiling point defined by the pressure and temperature of the water. The laundry treating appliance can be a washer/dryer combination or a stand-alone dryer. 
     Traditional vapor compression distillation assemblies and processes for distillation or reclamation of water can be effective, but can also be inefficient, employ high operating temperatures, and use expensive materials for construction. Heating the liquid to the boiling point for evaporation calls for significant energy input and can result in long start-up times for the system to warm up to appropriate operating temperatures. As a result, there is either a significant lag time to allow for pre-heating from a cold start, which can take several hours, or the assembly must be run as a steady state process, such as a standby mode which continuously maintains preheat temperature so that startup can occur quickly, which wastes energy. The high temperatures sustained within the vapor compression distillation assembly create a need to use expensive materials that can withstand the high temperatures without cracking or damage, as well as for insulative materials to be incorporated to reduce the amount of heat energy lost from the vapor compression distillation assembly. Additionally, after evaporation and condensation, the distillate liquid can also have a high temperature, which may not be suitable for the desired end use, for example, if the distillate is intended to be used for immediate washing or rinsing with cold water. 
     While the laundry treating appliance described herein has a horizontal axis, the exemplary laundry treating appliance is not limited to implementations in a horizontal axis laundry treating appliance. Depending on the implementation, a vertical axis dryer or a combination washing machine and dryer; a tumbling or stationary refreshing/revitalizing machine; an extractor; or a non-aqueous washing apparatus; can all be suitable environments for the disclosure as described herein. 
     As used herein, the term “vertical axis” and “horizontal axis” refer to the manner in which mechanical energy is primarily applied to laundry treated in the laundry treating appliance and is not an express limitation on the operational axis of the appliance. For vertical axis washing machines, a clothes mover, such as an impeller, pulsator, agitator, etc., rotates or reciprocates within a basket, which is typically stationary at the time, about a generally vertical axis to impart mechanical energy to the laundry. In a horizontal axis washing machine, a drum or basket is rotated about a generally horizontal axis to lift the laundry, which then falls in response to gravity. The repeated lifting/falling, which is referred to as tumbling, provides the mechanical energy to the laundry. In either machine the rotational axis need not be perfectly vertical or horizontal, as the case may be. It is acceptable that the axis be at an angle of inclination to the vertical or horizontal axis. 
       FIG.  1    is a schematic view of a laundry treating appliance in the form of a combination washer/dryer  10 . The combination washer/dryer  10  includes a structural support system comprising a cabinet  12  which defines a housing within which a laundry holding system  14  resides. The cabinet  12  can be a housing having a chassis and/or a frame defining an interior enclosing components typically found in a conventional combination washer/dryer, including but not limited to motors, pumps, fluid lines, controls, sensors, transducers, and the like. Only components necessary for a complete understanding of the disclosure set forth herein will be described in more detail as necessary. 
     The laundry holding system  14  can include a tub  16  supported within the cabinet  12  by a suitable suspension system and a drum assembly  17  provided within the tub  16 . An external containment cavity  15  can be defined as the space between the tub and the drum assembly  17 . The drum assembly  17  can include an outer drum  18  and an inner drum  20  provided within the outer drum  18  and defining an interstitial space  38  between the outer drum  18  and the inner drum  20 . The outer drum  18  can include drain ribs  70 . The inner drum  20  further defines at least a portion of a laundry treating chamber  22 . An interior wall  24  defining the inner drum  20  can include integral lifts  26  such that the interior wall  24  has a wave form with circumferentially spaced troughs  28  and crests  30 . Integral can refer to a structure that is one-piece or monolithic, such that the integral lifts  26  are part of the structure forming the inner drum  20 . While illustrated as integral lifts  26 , it is contemplated that the interior wall  24  can include conventional lifts coupled to the interior wall  24  and circumferentially arranged about the laundry treating chamber  22 . 
     A rear inner wall  32  and a front inner wall  34  define at least a portion of the laundry treating chamber  22 . The front inner wall  34  can have perforations  36  fluidly coupling the laundry treating chamber  22  to the external containment cavity  15 . The inner drum  20  extends along a substantially horizontal axis between the rear inner wall  32  and the front inner wall  34 . It should be noted and will be explained in more detail herein that the laundry treating chamber  22  and the interstitial space  38  between the outer and inner drums  18 ,  20  are isolated from each other to an extent that a pressure difference can be established between the two spaces. 
     A door  40  can be movably mounted relative to the cabinet  12 , by way of non-limiting example rotatably mounted to the left side of an opening  42  in the cabinet  12  through which laundry can be received within the laundry treating chamber  22 . The door  40  can selectively close both the tub  16  and the laundry treating chamber  22 . The door  40  can seal only against the tub  16  while leaving small gaps between the drum assembly  17  and the tub  16 . The small gaps ensure that clothing articles remain within the treating chamber  22 . An inner surface  44  of the door  40  defines a portion of the laundry treating chamber  22  when the door  40  is closed. A heater  46 , by way of non-limiting example an infrared heating element, can be mounted to the inner surface  44  of the door  40 . It is further contemplated that the heater can be located in any suitable location including a sump  94  ( FIG.  3   ) for heating both the water during a wash cycle and the drum assembly  17  during a dry cycle along with the air during a de-wrinkling cycle. At least one nozzle  48  can be provided between the tub  16  and the outer drum  18  within the external containment cavity  15 . The at least one nozzle  48  can be fluidly coupled to any number of water supplies to supply water to the tub  16 . 
       FIG.  2    is an exploded view of the tub  16  and drum assembly  17  where it can more clearly be seen that the front inner wall  34  can include a plurality of lifters  56  circumferentially arranged about an opening  58 . Lifters  56  can aid in lifting and tumbling laundry during operation, while integral lifts  26  can also perform a similar function while also directing water as will be described in more detail herein. The tub  16  can extend axially between a front and rear bulkhead  50 ,  52 . The front bulkhead  50  includes an opening  54 . The lifters  56  extend axially from the front inner wall  34 . Openings  54  and  58  are axially aligned with opening  42  in the cabinet  12  when assembled. The inner drum  20  can be sealed at the rear by the rear inner wall  32 . The rear inner wall  32  can be a ribbed wall as illustrated to direct water and engage laundry items during operation. 
     A vent and drain system  60  can be disposed in the interstitial space  38  ( FIG.  1   ). A coupling ring  61  can be formed to receive the inner drum  20  and circumscribe the outer drum  18 . A drain channel  62  formed by axially spaced channel walls  63  can be provided at the coupling ring  61 . The drain channel  62  can include lift walls  64  axially extending between the axially spaced channel walls  63 . Circumferentially spaced notches  65  can be disposed along an inner channel wall  63   a . A plurality of collection conduits  66  can extend axially from the coupling ring  61 . A plurality of drain conduits  68  can extend radially inward from the drain channel  62 . While illustrated as five collection conduits  66  and three drain conduits  68 , it should be understood that any number or combination of collection conduits and drain conduits is contemplated and is not meant to be limited by those illustrated. 
     The outer drum  18  includes the drain ribs  70  forming at least a portion of a collection of circumferentially disposed collection channels  72  within the outer drum  18 . The drain ribs  70  form conduits along an interior surface  71  of the outer drum  18 . The outer drum  18  can be sealed at the rear by a rear outer wall  74 . 
     A schematic of the combination washer/dryer  10  is illustrated in  FIG.  3    with the laundry holding system  14  including only the tub  16  and one nozzle  48  in dashed line for clarity purposes only with it being understood that the drum assembly  17  is in place as described herein. The combination washer/dryer  10  can include a reuse tank  80  fluidly coupled to a pump, illustrated herein as a vacuum pump  82 . It will be understood that the pump can be any suitable compressor or pump for creating a negative pressure relative to atmospheric pressure, including, by way of non-limiting example, a compressor or vacuum pump such as a positive displacement pump, an impeller driven compressor, or a piston pump compressor. A first vent  84  can be located at the top of the reuse tank  80  to vent air in and out as the reuse tank  80  is filled or drained. The first vent  84  can also vent non-condensable gases pumped into it. Non-condensable gases can be present in the liquid within the combination washer/dryer  10  as it is removed from laundry items. Non-condensable gases can include, by way of non-limiting example, gases dissolved in the liquid, other volatiles that may be present in the liquid, air that may be left within the laundry holding system  14  after the draw down to negative pressure due to an imperfect vacuum, or air that may leak into the laundry holding system  14  due to imperfect seals. It is also contemplated that a sensor  86 , by way of non-limiting example a conductivity sensor, is located within the reuse tank  80  to detect if the reuse tank  80  is full. By way of non-limiting example the reuse tank  80  can hold 25 to 32 liters of a liquid. 
     A flash evaporation starter  88  can be fluidly coupled to the reuse tank  80 . It is contemplated that the flash evaporation starter is directly coupled to the reuse tank  80  or indirectly coupled to the reuse tank  80  via the vacuum pump  82 . The flash evaporation starter  88  can be any apparatus to encourage flash evaporation of the liquid present within the laundry holding system  14 . Non-limiting examples of such an apparatus include a heating element or heater or an additional pump or compressor to aid in creating the negative pressure within the laundry holding system  14 . The heating element or heater can be located within a small pressure vessel to superheat a small volume of water that can be injected into the laundry holding system to provide an initial high volume of water vapor to begin the vapor compression process. 
     The combination washer/dryer  10  can also include a process tank  90 . The process tank  90  can be formed with a capacity of, by way of non-limiting example 18 liters to 25 liters. The process tank  90  can be fluidly coupled to a transfer pump  92  for moving water from a sump  94  to the process tank  90 , by way of non-limiting example at the end of a wash cycle or during/after a rinse cycle. It is further contemplated that a second vent  96  is located at a high point of the process tank  90  to allow air in or out as the process tank  90  is filled or drained. A second sensor  98 , by way of non-limiting example a float sensor, can be located within the process tank  90  to prevent from over filling. 
     A flow control mechanism  100 , by way of non-limiting example a pump, such as a positive displacement pump, or a valve, is fluidly coupled to the process tank  90  to allow water to be drawn or pumped from the lowest point in the tank into the at least one nozzle  48 . During operation, low pressure within the tub  16  can cause water from the process tank  90  to be drawn into the at least one nozzle  48  without the need of a pump or valve. Therefore, it is contemplated that in some aspects of the disclosure herein no flow control mechanism  100  is required. 
     A motor assembly  102  can include a motor  104  mechanically coupled to the laundry holding system  14  for rotating the tub  16  and/or the drum assembly  17 . It should be understood, that while the motor assembly  102  can be used for rotation of the tub  16 , a non-rotating tub is also contemplated and the motor assembly can be utilized for other mechanisms. A compressor assembly  106  can be part of the motor assembly  102 . A rear manifold  108  can be fluidly coupled to the compressor assembly  106  for moving fluids, including but not limited to condensate and condensable gases out of the laundry holding system  14  via the vacuum pump  82  to the reuse tank  80 . 
       FIG.  4    is an exploded view along an axis of rotation  101  of the motor assembly  102  according to an aspect of the disclosure herein. The motor assembly  102  can include the motor  104  for driving the tub  16  and/or drum assembly  17  and can include the compressor assembly  106 . The motor  104  can include a rotor  110  and a stator  112 . When assembled the stator  112  circumscribes the rotor  110  and is mounted to a stator mounting plate  114 . A separating wall  116  in the form of an open cylinder, can extend between the rotor  110  and the stator  112 . 
     The compressor assembly  106  can include an impeller  122  with a cover  120 . The impeller  122  can be have a standard impeller shape by way of non-limiting example a frusto-conical shape as illustrated. This shape is for illustrative purposes only and not meant to be limiting. Impeller vanes  124  can extend radially outward from a central axis of the impeller  122  corresponding to the axis of rotation  101 . An impeller housing  126  can include a first cylindrical portion  130  for housing the impeller  122  and a second cylindrical portion  132 , by way of non-limiting example circumferentially smaller than the first cylindrical portion  130 , for receiving a compressor motor housing  134 . The impeller housing  126  can include openings  128  through which fluids can flow. The impeller housing  126  can couple with the impeller  122  such that when the impeller  122  is operating fluids within the impeller vanes  124  can be ejected through the openings  128 . 
     The compressor motor housing  134  can include a circular base  136  from which a cylindrical housing  138  extends axially towards the cover  120 . The cylindrical housing  138  includes a cylindrical wall  144  extending from the circular base  136  and terminating in a tapered end  146  with an opening  148  ( FIG.  5   ). A connection conduit  149  can extend within the cylindrical wall  144  in a direction substantially parallel to the axis of rotation  101 . While illustrated as parallel to axis of rotation  101 , it should be understood that the connection conduit  149  can be disposed in any functional direction or orientation. A compressor motor  140  can extend through the cylindrical housing  138  with a portion extending through the opening  148  to mechanically couple to the impeller  122 . The rear manifold  108  includes a dividing arm  142  received within the cylindrical housing  138 . 
       FIG.  5    is an assembled cross-sectional view of the motor assembly  102  taken along line V-V of  FIG.  4   . The stator  112  can include a plurality of circumferentially spaced windings  150 . A plurality of corresponding circumferentially spaced magnets  152  are disposed within the rotor  110 . The rear manifold  108  includes two cooling cavities  154  for introducing cooling air to the compressor motor  140 , where at least one cooling cavity provides heated air exhaust. The rear manifold  108  can also include an exit conduit  156  fluidly coupling the vent and drain system  60  to the reuse tank  80  via the vacuum pump  82  ( FIG.  3   ). It can more clearly be seen that the impeller  122  defines a collection of circumferentially arranged openings  121  within the cover  120  to define a compressor inlet  125 . 
       FIG.  6    is an assembled perspective view of the vent and drain system  60  coupled to the inner drum  20  with the outer drum  18  illustrated in dashed line for clarity. The integral lifts  26  define at least a portion of the circumferentially disposed collection channels  72 . The crests  30  as described in  FIG.  1    form outer troughs  76  along an outer surface  78  of the inner drum  20 . The plurality of collection conduits  66  fluidly couple the interstitial space  38  between the outer and inner drums  18 ,  20  to the drain channel  62 . The plurality of drain conduits  68  fluidly couple the drain channel  62  to the motor assembly  102 . During operation, due to the combination of the compressor and an extreme volume change that occurs when a gas condenses to a liquid, compressed water vapor will move from right to left with respect to  FIG.  6    along outer surface  78  of the inner drum  20 . In turn non-condensable gasses will also move to the left end of channels  72 . The collection conduits  66  are provided to enable an exit of these non-condensable gasses from a trap formed at the left end of the collection channels  72 . The drain ribs  70  facilitate the movement of condensate formed along the interior surface  71  ( FIG.  2   ) of the outer drum  18 . The condensate moves within the channels  72  due to a rotation of the outer drum  18  at, by way of non-limiting example 130 rpm producing around 5 g, causing the much denser condensate to accumulate on the interior surface  71  of the outer drum  18  within the drain ribs  70 , which are sloped to collect condensate prior to extraction through drain conduits  68 . Extraction through the drain conduits  68  can occur when the drum is slowed at regular intervals to redistribute clothing within the treating chamber  22 . 
     Turning to  FIG.  7   , an assembled cross-sectional perspective view of the combination washer/dryer  10  is illustrated. The connection conduit  149  can fluidly couple the plurality of drain conduits  68  to the exit conduit  156 . A drain pipe  160  can fluidly connect the exit conduit  156  to the reuse tank  80  via the vacuum pump  82  ( FIG.  2   ), thus also fluidly connecting the interstitial space  38  with the reuse tank  80  and vacuum pump  82 . 
     A method of draining fluids disposed within the vent and drain system  60  can include flowing fluids (F) through the collection channels  72 . The drain ribs  70  can facilitate the flow of fluids (F), including but not limited to condensate and condensable gases, through the collection channels  72  and into the collection conduits  66 . The method can further include draining the fluids (F) into the drain channel  62  via the notches  65 . Collecting the fluids (F) in the collection conduits  66  can be facilitated by the lifts walls  64  through rotation. The lift walls  64  can form a “ferris wheel” for the water, lifting the water as the coupling ring  61  turns to a point where gravity works to pull the water down through the drain conduits  68 . The method can further include disposing fluids (F) into the motor assembly  102 . 
     The method can further include removing the fluids (F) through the exit conduit  156  via the connection conduit  149  and moving the fluids (F) into the reuse tank  80 . The fluids (F) drain out when the outer drum  18  has slowed so that there is less than 1 g of force on the outer or inner drums  18 ,  20 . The movement of the fluids (F) during such a draining method through the collection channels  72 , collection conduits  66 , drain conduits  68 , and into the exit conduit  156  to the reuse tank  80  can be facilitated completely by gravity. The drum must be slowed intermittently to drain out condensate that collects in drain channel  62 . 
     The combination washer/dryer  10  can perform washing and drying of clothing, as well as distilling any water used in washing to remove soil, detergents, water mineral hardness, etc. in order for the used water to be reused in a subsequent cycle. By way of non-limiting example, laundry items can be treated in 18 liters of water. Upon completion of a treatment cycle, used water can be drained into the process tank  90 . 
     In an exemplary cycle, the reuse tank  80  can hold 32 liters, providing a wash amount of 18 liters and two smaller 7 liter amounts provided directly from the reuse tank, can be used to rinse the treated laundry items. The smaller amount of water can be extracted via a spin cycle to, by way of non-limiting example 125% RMC (Remaining Moisture Content by weight). Typical horizontal washing machines extract 40%-50% RMC by spinning at high speeds producing g-forces ranging from 250 to 500 g&#39;s in order to extract water to these levels. In order for a 125% RMC to be achieved only speeds of between 120 and 140 rpm producing 3-7 g&#39;s is necessary. A lighter and less robust suspension system would be required and out of balance forces would be far less than in a typical washing machine. It is further contemplated that no suspension system at all would be required. A rubber boot typical for large vibrations and damping can also be eliminated in the combination washer/dryer  10  as described herein. 
     During the rinse cycle, water can be sprayed on the inside of the laundry items while the laundry items are held against the interior wall  24  of the inner drum  20  during, by way of non-limiting example, a 5 g spin. A slight slope of the inner drum  20  would cause used rinse water to flow toward the front inner wall  34  and through the perforations  36  in the front inner wall. Rinse water would then flow within the external containment cavity  15  to the sump  94 . The flow of used water can be further facilitated by the troughs  28  of the integral lifts  26 . This used water can also be transferred to the process tank  90  leaving 5 or 6 liters in the clothing to be extracted during a dry cycle. 
     The reuse tank  80  can be configured to hold liquid, which can include both water from condensation and a small amount of water vapor together with any non-condensible gases vented during a drying/distillation cycle. Any water from the vacuum pump  82  can be discharged into the reuse tank  80 . In order to further conserve water vapor, the water vapor can be condensed as it passes through any condensate already in the reuse tank  80 . Air and non-condensible gases can be vented in and out of the reuse tank via the vent  84 . The sensor  86  can detect if the reuse tank  80  is full. At the commencement of a wash cycle, the condensed water can be drained into the treating chamber  22  by the opening of a valve due to gravity. 
     At the end of the wash cycle and during/after the rinse cycle, the transfer pump  92  can move the water from the sump  94  at the bottom of the treating chamber  22  into the process tank  90 . When the wash cycle and/or rinse cycle have been completed and the drying and distillation cycle is to be commenced, the flow control mechanism  100  can allow water to be drawn from the process tank  90  into the at least one nozzle  48  to spray the used water on external surfaces of the outer drum  18  so that the water can be distilled. 
     When the drying and distillation cycle is commenced, evaporation of the water is initiated. In an exemplary embodiment, the initiation of the evaporation is a flash evaporation step. Vapor compression distillation methods can utilize heat in order to begin flash evaporation. Aspects of the present disclosure provide for a vapor compression distillation in which the need for heat to begin flash evaporation is reduced by instead or in addition using reduced pressure to cause flash evaporation while requiring less heat. The vacuum pump  82  can be operated to reduce the pressure within the treating chamber  22  to a negative pressure relative to atmospheric pressure. Specifically, the vacuum pump  82  can reduce the pressure within the treating chamber  22  by operating to draw air out of the treating chamber  22  and create a low pressure environment. The pressure within the treating chamber  22  can be reduced to the point at which the liquid spontaneously boils and flash evaporates. By reducing the operating pressure sufficiently, distillation and flash evaporation can occur at or near room or ambient temperature. This reduces start-up time requirements, and removes some high temperature-related needs for costly materials and insulation. Rather than lengthy pre-heating times, the initial draw down phase according to aspects of the present disclosure can be as short as minutes or seconds. An additional heating element, heater, pump, or compressor can aid in creating the negative pressure within the treating chamber  22 . Additionally coating the exterior of the outer drum wall  18  with a coating such as Cerakote™, or any suitable coating with a black body emissivity in the ninety percentile range, can enable absorbing of the infrared (IR) radiation from the heater  46  more readily than a stainless surface which typically has very low IR absorption. With a near vacuum state, transferring heat by convection is limited. By way of non-limiting example, an electric tubular heater, such as a Calrod heater, can be designed to radiate at 95% and above efficiency in the infrared spectrum, so that most of the energy can be transferred into the drum to build up the rate of evaporation over a period of time needed for the process. 
     It is contemplated that when the treating chamber  22 , and more specifically the external containment cavity  15 , is at a low pressure or near vacuum state, no additional pump or flow control mechanism is required for moving the used water from the process tank  90  into the nozzles  48 . Due to the low pressure or near vacuum state of the external containment cavity  15 , water will naturally flow from the process tank  90  into the at least one nozzle  48  toward the lower pressure or vacuum state of the external containment cavity  15 . As long as the flow rate of water is low compared to the gas removal rate of the vacuum pump  82 , the vacuum pump  82  can be utilized. If the vacuum pump  82  is not sufficient to provide a required spraying pressure, it is contemplated that an additional pump, which can be, by way of non-limiting example, a small diaphragm pump, can be utilized to pump the dirty water to be distilled onto external surfaces of the outer drum  18 . 
     Pumping water onto the external surfaces of the outer drum  18  can improve the efficiency of the vapor compression distillation process by allowing for the energy of condensation after the initial flash evaporation occurs to be transferred back through the outer drum  18  to sustain further evaporation. The exterior surface area of the outer drum  18  can serve to encourage and maximize evaporation performance, in addition to the use of low pressure or heat to cause spontaneous boiling and flash evaporation. This can serve to keep the distillation process going without requiring additional input of energy or while requiring minimal additional input of energy to the system. Additionally, the resulting distillate can be at or near room temperature, so it can be used for many end purposes without the need for cooling the distillate. The second sensor  98  can determine when all the water has been distilled. 
     The flash evaporation can be thought of as a method for rapidly initiating the vapor compression distillation process, and can also result in a slight reduction in the temperature of the treating chamber  22  and the outer drum  18 . Thus, in order for subsequent evaporation to continue, the heat lost during flash evaporation can be replaced by the heat of condensation that transfers through the outer drum  18  to sustain evaporation once the flash evaporation has initiated the process. It will be understood that the flash evaporation can provide a high rate of evaporation for a short period of time until the condensation portion of the process begins and serves to sustain the evaporation. 
     Upon commencing a dry cycle, when the vacuum pump  82  and compressor assembly  106  are turned on, a low pressure, or near vacuum, environment can be produced, which can be specifically in the external containment cavity  15 , to further extract used water from the laundry items. The compressor assembly  106  can include a compressor to pump the external containment cavity  15  to between 200 and 300 mBar, leaving the vacuum pump  82  to accomplish the remaining pressure decrease of between 170 and 270 mBar to accomplish a pressure of less than or equal to 30 mBar. In a preparation step for drying the laundry items and/or distilling the used water, the vacuum pump  82  and compressor assembly  106  are turned on and all appropriate valves are closed in order to evacuate the external containment cavity  15  to create a low pressure and near vacuum environment. It is contemplated that depending on the size of the vacuum pump  82 , this initial draw-down process can take 8-10 minutes. 
     In one aspect of the disclosure, the compressor assembly can be a turbo compressor, or 550 Watt compressor. Unlike centrifugal compressors, turbo compressors, or turbo chargers, are capable of generating higher pressure decreases. Utilizing a turbo compressor can provide high power during a draw-down process. A turbo compressor can provide at least 200 mBar of pressure decrease, requiring the vacuum pump  82  to provide at least 800 mBar instead of a full vacuum of 1000 mBar to reach a near vacuum state. Combining the turbo compressor with the vacuum pump  82  reduces the power that would otherwise be needed in the vacuum pump  82  for drawing down the external containment cavity  15  to a low pressure value of at 28 mBar, or as close to zero as possible. This pressure environment enables a flash evaporation at or near room temperature, which can be at or around 23° C. 
     In one aspect of the disclosure, the spontaneous evaporation can be started when a small amount, by way of non-limiting example 150 cc, of distilled water from the reuse tank  80  is introduced to the flash evaporation starter  88 . The flash evaporation starter  88  can be a small heated chamber that when in a closed state is a pressure vessel. Heat, by way of non-limiting example 700 W for 7-10 minutes, can be introduced to the small amount of distilled water in the small heated chamber to produce a super-heated state, which is the phenomenon in which a liquid is heated to a temperature higher than its boiling point, without boiling. 
     To ignite a vapor compression distillation process, the flash evaporation starter  88  is opened and throttled appropriately in order to release the super-heated distilled water between 15 to 20 seconds into the tub  16 . Spontaneous boiling and/or flash evaporation of the liquid within the treating chamber  22  occurs due to the operation of the flash evaporation starter  88  and the reduced pressure environment within the treating chamber  22 . Water contained within the liquid is evaporated to water vapor. 
     Simultaneously, the water vapor that is evaporated from the clothing and from the flash evaporator/starter  88  is drawn into the compressor inlet  125  of the compressor assembly  106  by the impeller  124 . The water vapor can come from treating chamber  22 , the external containment cavity  15 , or both. The water vapor becomes compressed and moves into the interstitial space  38  between the drum walls. The water vapor remains in a modest superheat condition at a higher pressure where condensation can occur in collection channels  72 . 
     Also during the drying and distillation process, the clothing is spun, by way of non-limiting example at 130 rpm to press the clothing against the interior wall  24  of the inner drum  20  with around 5 g&#39;s. This speed utilizes all of the surface area of the interior wall  24  of the inner drum  20  by increasing a contact surface area of a laundry item that may have very little actual surface contact at 1 g. The space present in between layers of wet clothing decreases and therefore reduces the heat transfer rate into the clothing. Simultaneously, water from the process tank  90  can be sprayed on external surfaces of the outer drum  18 . Water evaporated from the laundry items and condensing on the outer surface  78  of the inner drum  20  along with the distillation taking place on exterior surfaces  118  of the outer drum  18  can equal a total of up to 500 cc/minute evaporation and condensation. 
     Because the water condensing on the outer surface  78  of the inner drum  20  has a slightly elevated temperature due to the compression process, and then comes into contact with the outer drum  18 , which has a lower temperature than the water vapor due to the liquid from the process tank  90  being sprayed on and evaporated from the external surfaces of the outer drum  18 , the water vapor is condensed between the inner drum  20  and the outer drum  18 , where it then flows to the vent and drain system  60  as previously described. In addition, as the water vapor condenses on the inner drum  20 , the energy of condensation is transferred through the outer drum  18  to further encourage evaporation on the outer surfaces of the outer drum  18 . The resulting distillate exits the vent and drain system  60  at a temperature that can be only a few degrees above the temperature of the liquid originally in the treating chamber  22 , resulting in only a small amount of energy loss due to the vapor compression distillation method. 
     It is contemplated that the rate of treatment of the used water in the process tank  90  would exceed the rate at which condensation is formed from the clothing on the inside. In one non-limiting example, the maximum evaporation rate is 120 cc/min, or equal to a typical vented dryer, and the distillation process is 380 cc/min. As the laundry items become dry, the rate of evaporation would inevitably decrease to near zero and the rate of distillation on the exterior surfaces  118  of the outer drum  18  would approach 500 cc/min. 
     In one non-limiting example, the entire load of water that for evaporation and distillation is 25-31 liters, at the rates described herein, the drying/distilling cycle would take approximately 50-70 minutes. This is an improvement over typical combination washer/dryers. Additionally the combination washer/dryer  10  is ventless, and therefore does not pump prodigious air out of the house necessitating balance by an air conditioner or heater in the house. Furthermore, because of the distillation process, a net use of 1.5 liters of water is required for the washing process, vastly improving water usage when compared to a typical combination washer/dryer. 
     Additionally, a de-wrinkling process can occur at a conclusion of the drying and distillation cycle. The heater  46  in the door  40  can be turned on while the drum speed is slowed to allow tumbling. The laundry items can therefore be heated to a temperature that combined with the little remaining moisture, would de-wrinkle the clothing. When the distillation process is done, and de-wrinkling accomplished, the machine can be stopped, at which point the vacuum can be released via a valve. 
     Any dirty water left in the sump  94  or in the bottom of the process tank  90  can be pumped to a removable reservoir  380  ( FIG.  9   ). A user can remove the reservoir and dump the dirty water prior to the next cycle. The user can rinse and fill the reservoir with 1.5 liters for the next cycle. The 1.5 liters can ensure replacement of any lost condensate or any remaining water in the laundry items. 
     Additionally, a filter can be provided at the compressor to capture whatever lint could otherwise be carried into the vacuum pump  82 . While very little lint is expected to be suspended at such a low pressure, a filter can prevent any long term accumulation of lint on the walls in the interstitial space  38  between the outer and inner drums  18 ,  20 . 
     It should be understood that all numerical values used are for illustrative purposes only and not meant to be limiting. The numerical values could vary based on tradeoff decisions during manufacture while the process described herein would remain the same. 
       FIG.  7   a    more clearly illustrates the separate laundry treating chamber  22 , interstitial space  38 , and the external containment cavity  15  by removing some of the lines representing the 3-D nature of  FIG.  7   . It can more easily be seen that the laundry treating chamber  22  is defined by the inner drum  20 . The interstitial space  38  is defined between the outer and inner drums  18 ,  20 . Furthermore the external containment cavity  15  is separated from the interstitial space  38  by the outer drum  18 . 
     Turning to  FIG.  8   , a schematic view of a dryer  210  according to another aspect of the disclosure herein is illustrated. Aspects of the dryer  210  are similar to the combination washer/dryer  10 . Therefore, like parts will be identified with like numerals increased by 200, with it being understood that the description of the like parts of the combination washer/dryer  10  apply to the dryer  210  unless otherwise noted. 
     The dryer  210  includes an outer and inner drum  218 ,  220  defining an interstitial space  238 . An infrared absorbing coating can line an outer surface  318  of the outer drum  218 . An infrared heater  246  can be coupled to the outer surface  318  to radiate the outer surface  318  as it is rotated. The infrared heater  246  can be mounted to or connected with the outer surface  318  in any suitable manner. A laundry treating chamber  222  is defined by the inner drum  220  and sealed by a door  240 . A release button  362   a  can be provided within the laundry treating chamber  222 , by way of non-limiting example on the door  240 . A relief valve  364  can also be provided at a rear portion of the dryer  210 . A vacuum pump  282 , motor  302 , and compressor assembly  306  can be fluidly coupled to the interstitial space  238 . 
     The compressor assembly  306  can be driven by the motor  302  and a separate motor not shown can drive the outer and inner drums  218 ,  220  by a belt as is used in a typical venter dryer. A flash evaporation starter  288  along with a vacuum pump  282  can also be provided in the dryer  210 . Alternatively the heater  246  can add energy to the outer drum  218  to build up to the full rate over a period of time. 
     It is further contemplated that the heater  246  can be utilized to initiate the process in place of the flash evaporation starter  288  described herein. In one aspect, the heater  246  can be located where the flash evaporation starter  288  is illustrated, below the outer drum  218 . It is also contemplated that the heater  246  be located in the sump  94  as described for the washer/dryer combo  10  and is the same heater as is used to heat the water during a washing cycle. The heater  246  can include a high emmissivity coating and can be a standard calrod heater with a reflector under it. Due to an absence of any gasses, infrared radiation provides a primary means to heat the outer drum  218  while in a near vacuum state. The heater  246  can provide temperatures between 450 and 550 C and an IR radiation of between 2 micrometers and 10 micrometers. Other suitable temperatures and ranges for IR radiation are contemplated as well. The heater can be used to both start the process and warm the laundry items to the end of a cycle. 
     The relief valve  364  can open on a discharge side of the compressor assembly  306  coupling the interstitial space  238  to the atmosphere when the relief valve  364  is opened. At a predetermined lower pressure in the interstitial space  238 , the atmospheric pressure outside the relief valve  364  would cause the relief valve  364  to close. By way of non-limiting example, this predetermined lower pressure could be 75% atmospheric pressure inside the tub walls, allowing the compressor assembly to pump at a very high rate initially, and reducing the amount that must be pumped down by the vacuum pump  282 . The vacuum pump  282  is connected to the interstitial space  238  into which the compressor assembly  306  discharges. In an aspect of the disclosure herein, the laundry treating chamber  222  operates at or about 28 mBar while the interstitial space  238  is at 87 mBar (and substantially below atmosphere of 1000 mBar), a pressure ratio of 3.1:1. The vacuum pump  282 , would only need to draw down to 87 mBar which, by way of non-limiting example, a small, low technology positive displacement pump could achieve. 
     The release button  362   a  can be in the form of a large obvious button placed inside the drum on the door, or in any other convenient location which would instinctively be pressed in an attempt to escape. Pressing of the release button  362   a  would cause a valve, by way of non-limiting example the relief valve  364 , to open allowing atmosphere back into the laundry treating chamber  222  and preventing the vacuum pump  282  from continuing to evacuate the laundry treating chamber  222 . It is further contemplated that the release button  362   a  would include an external button  362   b  that also capable of breaking the vacuum in the event a user external of the laundry treating chamber  222  realized a situation of entrapment has occurred. While illustrated on the dryer  210 , it is also contemplated that a release button  362   a  can be incorporated in the combination washer/dryer  10  as described herein. 
     Turning to  FIG.  9   , a perspective rear view of the dryer  210  according to an aspect of the disclosure herein is illustrated. It is contemplated that the condensate tank  390  is located on top of the dryer  210  for easier access for a user. A vent and drain system  260  can be integral with the dryer  210  and fluidly coupled to a cooling assembly  360  including an air conduit  374 . It is further contemplated that the vent and drain system  260  features ribbed walls  370  that can form collection channels  272 , illustrated in dashed line and more clearly described previously as collection channels  72 , in the interstitial space  238  between the outer and inner drums  218 ,  220 . The collection channels  272  can be fluidly coupled to the compressor assembly  306  by a plurality of collection conduits  266 . 
     Similar to the combination washer/dryer  10  described herein, the dryer  210  can utilize vapor compression distillation and flash evaporation for drying laundry items. In flash evaporation, the extremely high rate of evaporation that can occur when water suddenly is above the boiling point defined by the pressure and temperature of the water, by way of non-limiting example, when laundry items and water are heated to 43° C., which is 20° C. above a 23° C. boiling point at 28 mBar, a large potential of evaporation can be produced using a low power heater. Reduction of pressure, by way of non-limiting example utilizing the vacuum pump  82 , will enable the evaporation at a high rate until the heat content of the 20° C. difference in the wet clothing is consumed. This allows a brief surge period of evaporation during which condensation can be established at a high rate. The process can then be sustained at that high rate using a low power rate of 400-500 watts. 
     In another aspect of the disclosure herein, a fan  372  can be provided at a bottom portion of the air conduit  374  and exhaust under the outer and inner drums  218 ,  220 . The air conduit  374  includes an inlet  376  around the condensate tank  390 , in the top corner of the cabinet  212 , thus heating the air (A 1 ) and claiming some heat in non-condensable gases and uncondensed water vapor and the condensate itself that may be lost otherwise to the process. This air (A 1 ) can be cooling air (A 2 ) for the compressor assembly  306  due to the relatively lower temperature with respect to the compressor assembly  306  during operation. Rejected heat from the compressor assembly  306  can be captured forming hot air (A 3 ) which is then blown over the vacuum pump  282  and under the outer and inner drums  218 ,  220  where it will rise over the tub and transfer some of the heat into the tub. The air blown over the pump down low can induce air around it thus taking cool air from down low to aid in cooling the pump motor. A convection is set up around the tub where the cooled air drops down to the bottom to be reheated. The cabinet  212  can be insulated to prevent heat loss. In other words, the cooling assembly  360  draws air through a heat exchanger into the condensate tank  390  to cool residual water vapor from the vacuum pump  282  venting into the condensate tank. This cooling air then proceeds via a conduit  374  to cool the compressor assembly  360 , motor  302 , and vacuum pump  282 . The cooling assembly  360  can be fluidly coupled to a condensate tank  390 . 
     It is further contemplated that any steam or water vapor created when laundry items contact the inner drum  218  will transfer that heat further into the treating chamber  222 . If this heat re-condenses, this energy is not lost, but will eventually cause evaporation towards the center of the laundry treating chamber  222 , as previously described in detail with respect to the combination washer/dryer  10 . It is therefore contemplated that zero or very little rotation may be needed to complete drying. This is possible because the heat of condensation is conducted through a wall and into contact directly with the clothing. 
     A removable reservoir  380  can be provided at any portion of the dryer  210  either on a front bulkhead near the door, or in a back bulkhead, for collecting water during a drying cycle with a provision for the customer to remove it and dump it at the conclusion of the cycle, or to have a drain into a small sump pump after the vacuum is released with a pressure actuated valve. The water can be removed by the customer down low, or pumped with a small pump up to a reservoir up high. 
     The low pressure drying process can be controlled such that some wetness remains in the laundry items at the end of a cycle, as opposed to being bone dry. Since the specific heat of clothing without water is significantly less when dry, a warming can occur without the expenditure of significant amounts of energy when clothing is mostly dry. Additionally, the vacuum can be released during this warming allowing air to convect some heat in addition to direct contact with the drum. If needed, the drum can rotate more quickly for a more vigorous tumble in a de-wrinkling cycle as previously described herein, for a short time, thus still limiting clothing damage. 
     Pressure within the laundry treating chamber  222  and the interstitial spaces  238  can be monitored using temperature sensors and/or conduction sensors. By way of non-limiting example, after the drying process is started, the evaporation rate can decrease due to less water available to evaporate, the pressure can therefore be lowered inside the laundry treating chamber  222  and/or raised inside interstitial space  238 , because there is less water vapor flow. In the event that the compressor assembly continues operating at the same rate, the pressure inside the laundry treating chamber  222  will lower, since it is now ahead of the evaporation rate. This pressure drop can signal a controller that evaporation has slowed. The machine can then respond by reducing the speed of the compressor assembly until the pressure is returned and maintained at a desired set point. As the cycle progresses, the speed of the compressor assembly can be lowered to a point that further speed changes affect very little in terms of the sensors. Little change in the sensors can be a signal that very little evaporation is occurring and the laundry items are dry. On the other hand, if the pressure rises inside the tub, this is indication that the compressor is not keeping up with evaporation. Thus an impeller speed increase is in order. A supplemental temperature measure could be done to back up the primary decision using pressure. 
     The aspects of the disclosure described herein disclose a laundry treating appliance, for example, a dryer or a combination washer/dryer, as well as a laundry treating method for said laundry treating appliance, wherein vapor compression distillation can be leveraged to aid in and accomplish drying of the laundry items to be treated. This results in improved efficiency of the laundry treating appliance, less water consumption needed for a cycle of operation, and a shorter cycle time than typical, in particular in the context of the combination washer/dryer. In addition, as compared to a typical vapor compression distillation assembly, the assemblies and methods of the present disclosure allow for the elimination of the considerations associated with the high temperatures of traditional vapor compression distillation assemblies, such as allowing for the use of less expensive materials that do not need to be able to withstand higher temperatures, and eliminating the need for insulative materials to be included to prevent heat loss from the vapor compression distillation assembly. By operating the laundry treating appliance below atmospheric pressure and at or near ambient temperatures, the expense of additional heaters or heating elements can be eliminated or reduced. The compressor or vacuum pump, such as a positive displacement compressor, can be small and low cost and can reduce pressure sufficiently in a short period of time to reduce pre-heating and start up time. 
     The dryer or combination washer/dryer disclosed herein can be provided with a vapor compression distillation assembly similar to or the same as the vapor compression distillation assembly in U.S. Provisional Patent Application No. 62/646,551, filed Mar. 22, 2018, entitled “VAPOR COMPRESSION DISTILLATION ASSEMBLY,” which is herein incorporated by reference in full. 
     To the extent not already described, the different features and structures of the various embodiments of the present disclosure may be used in combination with each other as desired. That one feature may not be illustrated in all of the embodiments is not meant to be construed that it cannot be, but is done for brevity of description. Thus, the various features of the different embodiments may be mixed and matched as desired to form new embodiments, whether or not the new embodiments are expressly described. 
     While aspects of the present disclosure have 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 present disclosure which is defined in the appended claims.