Patent Publication Number: US-10314459-B2

Title: Dishwasher with sound attenuation toe kick panel

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims priority to and is a continuation-in-part of U.S. patent application Ser. No. 15/065,232, filed Mar. 9, 2016, now U.S. Pat. No. 10,098,520, which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Automatic dishwashers for use in a typical household include a tub defining a treating chamber and a spraying system for recirculating liquid throughout the tub to remove soils from the dishes and utensils. Two common configurations are a door-type, where a pivoting door provides access to a treating chamber where dishes are washed or a drawer-type where a drawer provides access to the as well as defining a major portion of the treating chamber. In either configuration, a rack for holding dishes to be cleaned is typically provided within the treating chamber. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one aspect, the disclosure relates to a dish treating appliance for treating dishes according to an automatic cycle of operation. The dish treating appliance includes a tub at least partially defining a treating chamber and having an access opening to the treating chamber. A cover selectively opens and closes the access opening. A condenser assembly includes an inlet and an outlet, with the inlet fluidly coupled to the tub. A toe kick panel includes an exhaust conduit fluidly coupled to the outlet of the condenser assembly. The toe kick panel further includes at least one noise attenuation structure disposed in the exhaust conduit. 
     In another aspect, the disclosure relates to a toe kick panel for an appliance having a treating chamber and a condenser fluidly coupled to the treating chamber for treating an article according to an automatic cycle of operation. The toe kick panel includes a frame defining an interior and having an inlet and an outlet. An exhaust conduit extends between the inlet and the outlet, and fluidly couples the condenser at the inlet. At least one noise attenuation structure is provided in the exhaust conduit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings: 
         FIG. 1  is a schematic, cross-sectional view of a dishwasher with a condenser. 
         FIG. 2  is a schematic view of a controller of the dishwasher of  FIG. 1 . 
         FIG. 3  is a top perspective view of the dishwasher of  FIG. 1 . 
         FIG. 4  is a bottom perspective view of the dishwasher of  FIG. 3  illustrating an outlet section of the condenser showing a typical outlet in dashed line. 
         FIG. 5  is a schematic, cross-sectional view of the condenser walls showing a multi-layer material. 
         FIG. 6  is a schematic, cross-sectional view of the multi-layer material showing compressed and non-compressed sections. 
         FIG. 7  is a plot illustrating exemplary decibel levels for the dishwasher of  FIG. 1  and a contemporary dishwasher. 
         FIG. 8  is a bottom perspective view of the dishwasher of  FIG. 3  having a toe kick area with insulation. 
         FIG. 9  is a front view of a toe kick plate including an exhaust conduit having noise attenuation structures. 
         FIG. 10  is sectional view taken across section X-X of  FIG. 9 , illustrating perforations in baffles as the noise attenuation structures. 
         FIG. 11  is an exploded view of the toe kick panel of  FIG. 9 . 
     
    
    
     DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     Automatic dishwashers can include a drying cycle which can include heating the treating chamber to evaporate a part of liquid used to wash or rinse the dishes and can include a condenser to further remove humidity from the humid air within the treating chamber. Typical condensers highly depend on the temperature difference between the humid air and the condenser walls. A reduction in this temperature difference reduces condenser efficiency. Often, the walls are thin, requiring minimal cooling to maintain the temperature difference. Condenser walls permit noise to escape from the condenser and the treating chamber, generating noise pollution into a consumer&#39;s kitchen or home. In order to combat the noise, sound blankets and other insulation are used to attenuate the noise pollution created by the dishwasher but these add cost and assembly time to the dishwasher. 
     In  FIG. 1 , an automated dishwasher  10  includes a chassis  12  to define an interior of the dishwasher  10  and can include a frame, with or without panels mounted to the frame. A tub  14  can be provided within the chassis  12  and can at least partially define a treating chamber  16 , having an open face, for washing dishes. A closure such as a cover or a door assembly  18  can be movably mounted to the dishwasher  10  for movement between opened and closed positions to define an access opening  22 , the door assembly  18  selectively opening and closing the access opening  22 . Thus, the door assembly  18  provides accessibility to the treating chamber  16  through the access opening  22  for the loading and unloading of dishes or other washable items. It should be appreciated that the door assembly  18  can be secured to the lower front edge of the chassis  12  or to the lower front edge of the tub  14  via a hinge assembly (not shown) configured to pivot the door assembly  18 . When the door assembly  18  is closed, user access to the treating chamber  16  can be prevented, whereas user access to the treating chamber  16  can be permitted when the door assembly  18  is open. 
     The chassis  12  can further comprise a bottom panel  20  disposed beneath the pivot point of the door assembly  18 . The door assembly  18  is shown in an exemplary closed position, but can be selectably opened to provide access to the treating chamber through an access opening  22 . 
     Dish holders, illustrated in the form of upper and lower dish racks  24 ,  26 , are located within the treating chamber  16  and receive dishes for washing. The upper and lower racks  24 ,  26  are typically mounted for slidable movement in and out of the treating chamber  16  for ease of loading and unloading. Other dish holders can be provided, such as a silverware basket. As used in this description, the term “dish(es)” is intended to be generic to any item, single or plural, that can be treated in the dishwasher  10 , including, without limitation, dishes, plates, pots, bowls, pans, glassware, and silverware. 
     A spray system is provided for spraying liquid in the treating chamber  16  and is provided in the form of a first lower spray assembly  28 , a second lower spray assembly  30 , a rotating mid-level spray arm assembly  32 , and/or an upper spray arm assembly  34 . Upper sprayer  34 , mid-level rotatable sprayer assembly  32  and lower rotatable sprayer assembly  28  are located, respectively, above the upper rack  24 , beneath the upper rack  24 , and beneath the lower rack  26  and are illustrated as rotating spray arms. The second lower spray assembly  30  is illustrated as being located adjacent the lower dish rack  26  toward the rear of the treating chamber  16 . The second lower spray assembly  30  is illustrated as including a vertically oriented distribution header or spray manifold  52 . Such a spray manifold is set forth in detail in U.S. Pat. No. 7,594,513, issued Sep. 29, 2009, and titled “Multiple Wash Zone Dishwasher,” which is incorporated herein by reference in its entirety. 
     A recirculation system is provided for recirculating liquid from the treating chamber  16  to the spray system. The recirculation system can include a sump  40  and a pump assembly  42 . The sump  40  collects the liquid sprayed in the treating chamber  16  and can be formed by a sloped or recessed portion of a bottom wall of the tub  14 . The pump assembly  42  can include both a drain pump  44  and a recirculation pump  46 . The drain pump  44  can draw liquid from the sump  40  and pump the liquid out of the dishwasher  10  to a household drain line (not shown). The recirculation pump  46  can draw liquid from the sump  40  and the liquid can be simultaneously or selectively pumped through a supply tube  50  to each of the assemblies  24 ,  26 ,  28 ,  30  for selective spraying. While not shown, a liquid supply system can include a water supply conduit coupled with a household water supply for supplying water to the treating chamber  16 . A heating system including a heater  54  can be located within the sump  40  for heating the liquid contained in the sump  40  or heating the dishwasher during a drying cycle, for example. 
     A controller  60  can also be included in the dishwasher  10 , which can be operably coupled with various components of the dishwasher  10  to implement a cycle of operation. The controller  60  can be located within the door  18  as illustrated, or it can alternatively be located somewhere within the chassis  12 . The controller  60  can also be operably coupled with a control panel or user interface  62  for receiving user-selected inputs and communicating information to the user. The user interface  62  can include operational controls such as dials, lights, switches, and displays enabling a user to input commands, such as a cycle of operation, to the controller  60  and receive information. 
     A condenser  70  can be provided between the chassis  12  and the tub  14 , extending along a side portion of the tub  14 . The condenser  70  can mount to the chassis  12  or the tub  14 , such as by fastening with fasteners or by welding. An inlet section  72  can provide fluid communication between the treating chamber  16  and the condenser  70  near the top of the treating chamber  16 . The inlet section  72  feeds air from the treating chamber  16  to the condensing section  74 . The condensing section  74  can comprise an integrated water inlet  76 , such that water and condensed liquid can be supplied to the treating chamber  16  from the water inlet  76 . An outlet section  78  fluidly couples to the condensing section  74  opposite of the inlet section  72 . The outlet section  78  comprises an outlet conduit  80  and an exhaust outlet  82  for exhausting the condensed airflow to the ambient. The outlet section  78  can be formed from multi-layer material or a molded polyester to improve sound attenuation. 
     As illustrated schematically in  FIG. 2 , the controller  60  can be coupled with the heater  54  for heating the wash liquid during a cycle of operation, the drain pump  44  for draining liquid from the treating chamber  16 , and the recirculation pump  46  for recirculating the wash liquid during the cycle of operation. Additionally, the controller  60  can be coupled to the condenser  70  for selectively operating the condenser  70  during the cycle of operation, such as a drying cycle. The controller  60  can be provided with a memory  64  and a central processing unit (CPU)  66 . The memory  64  can be used for storing control software that can be executed by the CPU  66  in completing a cycle of operation using the dishwasher  10  and any additional software. For example, the memory  64  can store one or more pre-programmed cycles of operation that can be selected by a user and completed by the dishwasher  10 . The controller  60  can also receive input from one or more sensors (not shown). Non-limiting examples of sensors that can be communicably coupled with the controller  60  include a temperature sensor and turbidity sensor to determine the soil load associated with a selected grouping of dishes, such as the dishes associated with a particular area of the treating chamber. 
     Turning to  FIG. 3 , the chassis  12  has been removed from the dishwasher  10  illustrating the outer sides of the tub  14 . The condenser  70  includes a plurality of walls  100  disposed within the condensing section  74 . The walls  100  extend from the sides of the condenser  70  partially across the condensing section  74  internally, defining a serpentine airflow path within the condensing section  74 . The condensing section  74  further includes an inlet wall  102 , separating the water inlet  76  ( FIG. 1 ) from the rest of the condensing section  74 . A supply of water can be fed to the condenser  70  from a water conduit  104 , where the supply of water can be fed into the treating chamber  16  through the water inlet  76 . The condenser  70  can mount to the tub  14  or, alternatively, the chassis  12  by a suspension  84 , illustrated as an exemplary spring. 
     An intermediate conduit  106  fluidly couples the condenser conduit  74  to the outlet section  78 . The outlet conduit  80  can run along the bottom of the dishwasher  10 , behind the bottom panel  20 , exhausting the condensed air through the exhaust outlet  82 . Additionally, the bottom panel  20  can comprise a toe kick area  108 , extending below the bottom panel  20 . The toe kick area  108  can comprise, for example, a kick plate preventing a user from kicking the outlet section  78 . The outlet conduit  80  can extend along the toe kick area  108  having the exhaust outlet  82  located opposite of the condensing section  74  relative to the dishwasher  10 . The outlet conduit  80  can extend along part of or the entire toe kick area  108 , defined by placement of the exhaust outlet  82 . 
     Turning now to  FIG. 4 , a bottom perspective view of the dishwasher  10  best illustrates the outlet section  78  of the condenser  70 . The outlet section  78  couples to the condensing section  74  via the intermediate conduit  106 , feeding a fan  122  of the condenser  70  the condensed air from the condensing section  74 . The fan  122  can draw moist air from the treating chamber  16  through the inlet section  72  and into the condensing section  74  to condense the moist air. 
     The outlet conduit  80  can further comprise a forward conduit section  124 , a ducting turn  126 , a lateral conduit section  128 , and an exhaust section  132 . The fan  122  pushes the condensed air through a forward conduit section  124  of the outlet conduit  80 . The forward conduit section  124  moves the condensed air toward the front of the dishwasher  10  where it turns at a ducting turn  126  and moves along the front of the dishwasher  10  along a lateral conduit section  128 . The lateral conduit section  128  extends along at least a portion of the toe kick area  108 . The lateral conduit section  128  fluidly couples to an exhaust section  132  where the condensed air exhausts through the exhaust outlet  82 . The lateral conduit section  128  can mount to the bottom of the tub  14  or to a cover plate  130  for covering the controller. 
     A contemporary exhaust outlet  134  utilized in the prior art is shown in dashed line. The contemporary exhaust outlet  134  is located such that the fan  122  typically pushes the condensed air forward and immediately out of the condenser  70  and dishwasher  10 . The noise associated with the fan  122  also travels out the typical exhaust outlet  134 , generating a noise audible and recognizable by a user. Replacement of the contemporary exhaust outlet  134  with the illustrated and above described outlet section  78  greatly reduces the amount of noise emitted from the dishwasher  10 . 
     The condenser  70 , referred to hereinafter as a condenser assembly  70 , can comprise one or more of the inlet section  72 , the condensing section  74 , the outlet section  78 , the outlet conduit  80 , the exhaust outlet  82 , the intermediate conduit  106 , the fan  122 , the forward conduit  124 , the turn  126 , the lateral conduit section  128 , and the exhaust section  132 . Contemporary drying systems also utilize plastic, which does not contribute much for sound attenuation. The condenser assembly  70  described herein can be made of a multi-layer material or a molded polyester, both of which provide better sound attenuation. 
       FIG. 5  illustrates a multi-layer absorptive acoustic material  140  that can be utilized in portions of the condenser assembly  70 . Such a multi-layer material  140  attenuates the sound emanating from the treating chamber  16  and travelling through the condenser assembly  70  and out the outlet conduit  80 , as well as sounds generated by the fan  122  and the pump assembly  42 . The multi-layer material  140  can comprise multiple layers of molded polyester or other materials. The multi-layer material  140  can include, but is not limited to, two outer layers of polyester  142  with an inner layer of plastic  144  between the polyester layers  142  to form a composite acting as a moisture barrier. The total thickness of the multi-layer material  140  can be a minimum of 2.0 millimeters (mm) and a maximum of 25 mm. During a drying cycle, most of the noise generated by the dishwasher  10  is emanated as airborne noise. The multi-layer material  140  attenuates the airborne noise. Changing the noise frequency to a lower frequency to provide a more appealing sound quality. This reduces the dry noise sound of the dishwasher  10  and reduces the overall spectrum of the dry noise. 
     Turning to  FIG. 6 , the multi-layer material  140  can further be compressed where required to accommodate for the condenser assembly  70 , while remaining non-compressed where sound absorption is required. The multi-layer material  140  can have an interior flow conduit  152 , which can be any conduit described herein, for directing a flow of air  154  through the condenser  70 . A compressed portions  156  can be compressed to modify the condenser geometry by reducing the thickness of a portion of the condenser  70  providing additional dishwasher space where necessary. Non-compressed portions  158  can be utilized where sound attenuation is required, as the non-compressed portions  158  provide increased noise attenuation relative to the compressed portions  156 . 
     It should be appreciated that the layered structure as illustrated in  FIG. 5  is merely exemplary and that the multi-layer material  140  can comprise additional layering configurations, such as more or less layers, having additional or alternative materials between layers of polyester, etc. In one such example, the multi-layer material  140  can include a compressed four-layer material having two outer layers of polyester with two middle plastic layers. Additionally, polyester and plastic materials are exemplary and can be replaced with any suitable materials for attenuating noise within the condenser assembly  70 . 
     Looking at  FIG. 7 , a plot illustrates the decibel levels  180  for a similar dishwasher at different frequencies for a contemporary condenser and decibel levels  182  for the dishwasher  10  having a condenser assembly  70  utilizing the multi-layer material  140 . The decibel levels  180  for the contemporary condenser include a maximum decibel (dBA) level of about 39 dBA at 1250 Hertz (Hz), while the decibel levels  182  for the condenser assembly  70  having the multi-layer material  140  has a maximum decibel level of about 34 dBA at a frequency of about 800 Hz. The multi-layer material  140  is beneficial in attenuating the noise, decreasing the overall decibel level of the condenser assembly  70 , and shifting the frequency at which the highest decibel level occurs. 
     Furthermore, the multi-layer absorptive acoustic material  140  can attenuate the high frequency sound, as compared to a single layer of hard plastic material. Additionally, the multi-layer material  140  improves psychoacoustic metrics, such as time decay, loudness, and pleasantness, which helps to gain perception of improved drying sounds quality. The sound then emitted from the condensing section  72  is quieter, having less frequency content as compared to a single-layer plastic material. Overall sound quality emitted from the condenser assembly  78  is improved. 
     Turning now to  FIG. 8 , it can be appreciated that the toe kick area  108  can be moved forward, relative to the front of the dishwasher  10 . The forward disposition of the toe kick area  108  provides room for inserting layered insulation  150 , illustrated in dashed line, between the lateral conduit section  128  and the toe kick area  108 . While it is contemplated that the multi-layer material  140  can eliminate the need for insulation,  FIG. 8  contemplates utilizing additional insulation  150  between the condenser assembly  78  and the toe kick area  108 . It will be understood that the insulation  150  can be a minimal amount and that the overall insulation requirement for the dishwasher  10  can still be reduced as compared to contemporary machines. Thus, insulation cost can be reduced and space within the dishwasher chassis  12  is increased with less utilized insulation  150 . 
     It should be appreciated that the condenser assembly  70  in combination with the use of a multi-layer material  140  provides for attenuation of noise generated by the dishwasher  10 . The reduced noise provides for quieter operation with less frequency content for a preferable consumer experience. Additionally, the reduced noise levels require minimal or no insulation for noise attenuation for the condenser assembly  70 , increasing utilizable space within the dishwasher unit without increasing the overall noise of the dishwasher. Furthermore, the reduction of insulation reduces overall production cost for the unit. Routing the lateral conduit section  128  of the outlet conduit  80  and the condenser assembly  70  across the toe kick area  108  provides additional space for reducing the noise moving with the dry air. The increased space increases overall time in which air travels through the condenser assembly  70 , providing for longer opportunity to attenuate the condenser noise. The multi-layer material  140 , that can include materials such as polyester provides, for a reduction in overall decibel levels of the noise moving through the condenser unit as well as minimizes the frequency of the noise, providing a more appealing sound quality. 
     Referring now to  FIG. 9 , a toe kick panel  200 , which can be a toe kick panel provided at the toe kick area  108  of  FIGS. 3-8 , includes a frame  202 . For example, the toe kick panel  200  can be the exterior bottom panel  20  ( FIG. 1 ) covering the front of the dishwashing appliance at the base. Alternatively, the toe kick panel  200  can be a combination of the toe kick area  108  and the lateral conduit and exhaust sections  128 ,  132  for providing for exhausting of condensed air from the condenser  70 . See  FIG. 8 , for example. 
     The frame  202  can be made of the multi-layer absorptive acoustic material, such as the multi-layer material  140  of  FIG. 5 , for example, or any multi-layer material as described herein. Such multi-layer material can be compressed, as described in  FIG. 6 . An insulator  204  can at least partially define an exhaust conduit  206  with the frame  202 . The insulator  204  can be made of an insulative material, such as a polyester in one non-limiting example, and can be uncompressed as compared to the compressed material of the frame  202 . Such an insulator  204  can provide dampening of striking forces, such as kick, to the toe kick panel  200 . Simultaneously, the polyester can provide for noise attenuation at the toe kick panel  200 . The exhaust conduit  206  can fluidly couple a condenser to the exterior of the appliance, can be any condenser described herein, such as the condenser  70  of  FIG. 8 . 
     An inlet  208  and an outlet  210  can define a flow passage  212  through the exhaust conduit  206 . The inlet  208  can fluidly couple the exhaust conduit  206  to a condenser, such as the condenser  70  of  FIG. 8 , being coupled via the fan  122 . The outlet  210  can exhaust to the ambient, such as at the front and bottom of the appliance. At least one noise attenuation structure  214  can be provided in the exhaust conduit  206 , such that an airflow passing along the flow passage  212  passes through the noise attenuation structures  214 . While illustrated as extending fully across the exhaust conduit  206 , it should understood that the noise attenuation structures  214  can extend partially across the exhaust conduit  206 . Additionally, while two noise attenuation structures  214  are illustrated, any number, including one or more noise attenuation structure  214  can be included. 
     The noise attenuation structure  214  can attenuate noise passing along the exhaust conduit  206  while permitting exhausting of condensed air from a condenser. The reduced noise provides for quieter operation with less frequency content for a preferable consumer experience, while providing for exhausting of the condensed air exterior of the appliance. Additionally, less noise insulation is required reducing costs. Finally, condensed air is exhausted to the ambient as opposed to in a confined area adjacent the appliance, where waterproofing would otherwise be required, further reducing costs. 
     Referring now to  FIG. 10 , showing the toe kick panel  200  taken along section X-X of  FIG. 9 , the frame  202  includes a front panel  220  and a rear panel  222 . The front panel  220  couples to the rear panel  222  to define an interior  224  of the toe kick panel  200 . The insulator  204  is provided in the interior  224 , separated into a front portion  226  and a rear portion  228  complementary to the shape of the front and rear panels  220 ,  222 . The front portion  226  and rear portion  228  can be a single, integral component, and need not be separated. 
     Alternatively, the front panel  220  and the front insulator  226  can be a single integral element. As a multi-layer material  140 , similar to that of  FIG. 6 , the front panel  220  can be a compressed portion and the front portion  226  can be a non-compressed portion, as a single, integral unit. Similarly, the rear panel  222  can be a compressed portion and the rear portion  228  can be a non-compressed portion. The combination of the two units can define the exhaust conduit  206  and insulator  204 . The non-compressed portions further attenuate noise with improved sound absorption along the exhaust conduit  206 . The compressed portions as the front and rear panels  220 ,  222  attenuate any excess noise emanating from the non-compressed portions. 
     The noise attenuation structure  214  can be physical structure, such as a baffle  230 , for example, extending across the entire cross-sectional area of the exhaust conduit  206 . Alternatively, the noise attenuation structure  214  can be a panel having air passages or perforations. For example, the panel can be a multi-layer acoustic absorptive material, such as the multi-layer material as described herein, including a plurality of round perforations. In another example, the noise attenuation structure can be any porous material, wherein the air passages are defined by the pores of the porous material. While shown as extending across the entire exhaust conduit  206 , it should be appreciated that the baffle  230  can extend only partially across the exhaust conduit  206 . For example, the baffles  230  can be organized within the exhaust conduit  206  in an alternative pattern, extending only partially across the exhaust conduit  206 , to define a serpentine path through the exhaust conduit  206 . A serpentine path for the exhaust conduit  206  can further attenuate sound passing through the toe kick panel  200 . The baffle  230  can include a plurality of air passages, shown as perforations  232 , permitting a flow of air to pass through the baffles  230 . The perforations  232  permit the flow of air to pass along the exhaust conduit  206 , while providing the noise attenuation at the noise attenuation structure  214 . While the perforations  232  are shown as large openings, it should be appreciated that the perforations  232  can be much smaller. For example, the baffle  230  can be made of a porous material, with the perforations  232  represented as a porosity of the baffle  230 , permitting the flow of air to pass through the baffles  230  at a much slower rate as compared to the larger perforations  232 , while providing improved noise attenuation at the baffles  230 . Thus it should be appreciated that the concentration and size of the perforations  232  can be particularly adapted based upon the expected air flow rate through the exhaust conduit  206  and the noise attenuation needs along the exhaust conduit  206 . 
     Referring now to  FIG. 11 , the front and rear panels  220 ,  222  have been exploded illustrating front and rear insulators  226 ,  228 . The baffles  230  mount to the front insulator  226 , being spaced from one another by a distance Δ. While two baffles  230  are shown at the particular distance Δ, it should be understood that  FIG. 11  is only exemplary. Any number of noise attenuation structures  214  can be used at any distance Δ within the size of the appliance. Further, it should be understood the baffles  230  can mount to any structure adjacent the exhaust conduit  206 , such as to the frame  202 . The toe kick panel  200  can include any number of baffles  230  spaced at any distance Δ. The number of baffles  230  and the distance Δ between the baffles  230  can be adapted based upon the particular noise attenuation needs of the particular appliance. As such, the distance Δ would be equal among multiple baffles  230  throughout the exhaust conduit  206 , except for any anticipated dampening of the noise along the airflow path based upon the total number of baffles  230 . For example, the multi-layer material of the condenser, as described herein, can attenuate sound at a first anticipated frequency or loudness. The toe kick panel  200  can attenuate the sound exiting the condenser having another frequency and loudness, based upon the resultant attenuation within the condenser upstream of the toe kick panel  200 . 
     In one non-limiting example, the appliance can have a noise spectrum having a predetermined frequency of noise passed to the toe kick panel  200 . The predetermined frequency can be determined based upon noise generated in the tub or treating chamber, or passing through the condenser. Such a predetermined frequency can be determined based upon the particular appliance, or model thereof. The predetermined frequency can also be representative of a maximum or minimum frequency. Based upon the predetermined frequency of the particular appliance, the wavelength can be determined in air. Based upon the predetermined frequency and predetermined wavelength thereof, the baffles  230  can be spaced at the distance Δ defined as a quarter (25%) of the wavelength to attenuate the noise. At the distance Δ defined as the quarter wavelength, the baffles  230  effectively attenuate the noise of the exhausted, condensed air passing through the toe kick panel  200  and exhausting to the ambient. In addition to the spacing of the noise attenuation structures  214  or baffles  230 , the toe kick panel  200  can be made of the multi-layer material, such as that of  FIGS. 5 and 6 , to further attenuate any sound contacting the toe kick panel  200  within the exhaust conduit  206  in the areas between adjacent noise attenuation structures  214 . Furthermore, the bottom panel  20  ( FIG. 1 ) can be made of the multi-layer material, or other noise attenuation material as described herein, to attenuate any noise leaking from the toe kick panel  200 . Additional insulation material can be provided between the bottom panel  20  and the toe kick panel  200 , however, the noise attenuation can be significant enough that such insulation is not required or that the required insulation is reduced. 
     Such spacing of the noise attenuation structures, as well as the particular implementation thereof, including location, size, number, thickness, porosity, spacing, material, the air passages including number or size thereof, the frame, the multi-layer material, or the condenser, in non-limiting examples, can be tuned or particularly tailored based upon the anticipated frequency and loudness of the sound entering the toe kick panel  200 . 
     The toe kick panel  200  as described effectively attenuates noise or sound while permitting exhausting of condensed air from a condenser to the exterior of the appliance at the front. Spacing the noise attenuation structures at the quarter-wavelength can provide for improved noise reduction based upon a predetermined frequency of the particular appliance or model. Such a frequency, for example, can be a minimum or maximum frequency expected. The reduced noise provides for quieter operation with less frequency content for a preferable consumer experience. Additionally, less noise insulation is required reducing costs. Finally, condensed air is exhausted to the ambient as opposed to in a confined area adjacent the appliance, where waterproofing would otherwise be required, further reducing costs. 
     To the extent not already described, the different features and structures of the various embodiments 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 may not 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. All combinations or permutations of features described herein are covered by this disclosure. 
     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.