Abstract:
A dish washing machine including a tub configured to form a space for a dish to be washed, a door configured to open or close the tub, and an exhaust duct extended to an under portion of the door to exhaust air in the tub. Further, the exhaust duct has a lower end sloped with respect to an installation surface of the dish washing machine.

Description:
CROSS-REFERENCE TO A RELATED APPLICATION 
       [0001]    This application claims the benefit of Korean Patent Application No. 10-2007-0088674, filed on Aug. 31, 2007, which is hereby incorporated by reference in its entirety as if fully set forth herein. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a dish washing machine, and more particularly, to a dish washing machine that is capable of preventing moisture from being formed on a bottom or a wall around the bottom of the dish washing machine and preventing the bottom or the wall of the dish washing machine from being deformed due to the moisture. 
         [0004]    2. Discussion of the Related Art 
         [0005]    A related art dish washing machine sprays washing water on dishes placed in a tub to remove foreign matter, such as food waste left on the dishes, thereby automatically washing the dishes. Further, the operation of the dish washing machine generally includes a washing cycle for spraying washing water mixed with detergent in the tub containing the dishes to remove the foreign matter left on the dishes, a rinsing cycle for spraying washing water not mixed with the detergent in the tub to remove the remaining foreign matter and the detergent after performing the washing cycle, and a drying cycle for drying the dishes. 
         [0006]    Some dish washing machines use heated washing water or that spray steam during the washing cycle or during the rinsing cycle to further increase the washing effect. For example,  FIG. 1  illustrates a related art dish washing machine. 
         [0007]    As shown in  FIG. 1 , the related art washing machine includes a case  100  forming the external appearance of the dish washing machine, and a door  120  for opening and closing the case  100 . A tub  150  is also mounted in the case  100  and defines a space for receiving dishes to be washed. Further, a sump  200  is mounted below the tub  150  for storing washing water. 
         [0008]    In addition, the tub  150  includes shelves  160  and  170  for holding the dishes and spray arms  220  and  230  for spraying water toward the shelves  160  and  170 . Further, and as shown in  FIG. 1 , the washing machine also includes a fan  90  and exhaust duct  92  mounted at the door  120 . The fan  90  and exhaust duct  92  remove wet air from the tub  150 . In more detail, the exhaust duct  92  extends to a lower part of the dish washing machine and guides air exhausted by the fan  90  out of the dish washing machine. 
         [0009]    However, the related art dish washing machine has the following problems. 
         [0010]    First, as shown in  FIG. 2 , the dish washing machine is generally installed in a kitchen in a built-in structure together with other articles of kitchen furniture “f”, such as a sink, stove, etc. As a result, the opposite sides and the rear of the dish washing machine are closed and only the front of the dish washing machine having the door is unobstructed. 
         [0011]    Further, the exhaust duct  92  extends to the lower part of the dish washing machine, and therefore air is exhausted out of the dish washing machine through the lower part of the dish washing machine. However, and with reference to  FIGS. 1 and 2 , some of the exhausted is not exhausted through the front of the dish washing machine, but rather flows to the rear and the sides of the dish washing machine. 
         [0012]    Then, when the exhausted air flows to the rear and the sides of the dish washing machine, the air is not exhausted from the dish washing machine, because the rear and the sides of the dish washing machine are closed. As a result, the walls of the kitchen furniture “f”, installed adjacent to the sides of the dish washing machine or the installation surfaces of the dish washing machine become deformed due to the relatively high temperature, high-humidity air. Furthermore, the relatively high-temperature, high-humidity air is introduced into a gap defined between the bottom of the dish washing machine and the floor where the dish washing machine is installed, with the result that the bottom of the dish washing machine becomes covered with rust. 
       SUMMARY OF THE INVENTION 
       [0013]    Accordingly, one object of the present invention is directed to a dish washing machine that substantially obviates one or more problems due to limitations and disadvantages of the related art. 
         [0014]    Another object of the present invention is to provide a dish washing machine that is capable of preventing moisture from being formed on the bottom or the wall around the bottom of the dish washing machine and preventing the bottom or the wall of the dish washing machine from being deformed due to the moisture. 
         [0015]    To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the present invention provides in one aspect a dish washing machine including a tub configured to form a space for a dish to be washed, a door configured to open or close the tub, and an exhaust duct extended to an under portion of the door to exhaust air in the tub. Further, the exhaust duct has a lower end sloped with respect to an installation surface of the dish washing machine. 
         [0016]    In another aspect, the present invention provides a dish washing machine including a tub configured to form a space for a dish to be washed, a door configured to open or close the tub, and an exhaust duct configured to exhaust air in the tub to an under portion of the door and toward an opening direction of the door. 
         [0017]    Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings: 
           [0019]      FIG. 1  is a sectional view illustrating a structure of a related art dish washing machine; 
           [0020]      FIG. 2  is a front view illustrating the dish washing machine of  FIG. 1 , which is installed in a built-in structure; 
           [0021]      FIG. 3  is a sectional view illustrating a structure of a dish washing machine according to an embodiment of the present invention; 
           [0022]      FIG. 4  is a front view illustrating an interior of a door of the dish washing machine shown in  FIG. 3 ; 
           [0023]      FIG. 5  is a perspective view illustrating a portion of an exhaust duct of the washing machine shown in  FIG. 3 ; and 
           [0024]      FIG. 6  is a sectional view illustrating the lower end of the exhaust duct of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]    Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. 
         [0026]      FIG. 3  is a sectional view illustrating a fan and a fan housing of a dish washing machine according to an embodiment of the present invention. As shown in  FIG. 3 , the dish washing machine includes the case  100  forming the external appearance of the dish washing machine, the door  120  for opening and closing the case  100 , the tub  150 , the shelves  160  and  170 , and the spray arms  220  and  230 . These components are similar to those of the previously-described related dish washing machine, are denoted by the same reference numerals, and therefore a detailed description thereof is omitted. 
         [0027]    In addition, as shown in  FIG. 3 , the dish washing machine also includes a control panel  130  and a sump  205 . Further, the sump  205  includes a pump  210  for pumping washing water and a filter (not shown) for filtering the washing water. The sump  205  also includes a sump heater  290  for heating the washing water. 
         [0028]    In addition, the sump  205  is connected to a first water supply pipe  250 , through which fresh water is supplied from an external water source, and a drainage pipe  270 , through which the washing water in the sump  205  is drained to an outside of the washing machine. A first water supply valve  255  for controlling the supply of water into the sump  205  is also mounted on the sump  205 . 
         [0029]    Further, the upper shelf  160  and the lower shelf  170  are mounted at the upper part and the lower part of the tub  150 , respectively. Also, the upper spray arm  230  and the lower spray arm  220  are mounted at the upper part and the lower part of the tub  150  for spraying the water pumped by the pump  210  toward the upper shelf  160  and the lower shelf  170 , respectively. 
         [0030]    In addition, a top nozzle  240 , for spraying the water pumped by the pump  210  from the upper part to the lower part of the tub  150 , is mounted in the upper part of the tub  150 . A connecting pipe  110  connects the pump  210  and the top nozzle  240 . Further, in one embodiment, steam may be also sprayed or supplied into the tub  150  by the pump  210  and the spray arms  230  and  220  in addition to the washing water sprayed into the tub  150 . In more detail, the washing machine includes a steam generator  300  which is driven separately from the sump heater  290  mounted in the sump  205 . 
         [0031]    As shown in  FIG. 3 , the steam generator  300  communicates with a second water supply pipe  260  and also communicates with the tub  150  via a steam supply pipe  280 . A second water supply valve  265  for controlling the supply of water into the steam generator  300  is also mounted on the second water supply pipe  260 . 
         [0032]    In addition, the steam generator  300  includes a steam heater  310  for heating water supplied into the steam generator  300  and a water level sensor  320  for sensing the water level in the steam generator  300 . The water level sensor  320  may sense, for example, a low water level and a high water level. 
         [0033]    In more detail, the low water level is established to protect the steam heater  310 , and the high water level is established to prevent the overflow of the water supplied into the steam generator  300  from the steam generator  300 . Also, the steam generator  300  may further include a steam supply valve (not shown) for controlling the opening and closing of the steam supply pipe  280  to supply steam at a desired time. 
         [0034]    In addition, the dish washing machine may further include a contamination sensor (not shown) for sensing a contamination degree of washing water used to wash the dishes. For example, the contamination sensor may be mounted at one side of the sump  205  for sensing the contamination degree of washing water circulating in the tub. 
         [0035]    Further, a control unit (not shown) for controlling the dish washing machine is electrically connected to electrically-operating components, such as the control panel  130 , the pump  210 , and the steam generator  300 , to control the operation of the dish washing machine. In addition, the upper side of the tub  150  includes mounted components for exhausting high-temperature wet air in the tub  150 , heated by the steam and the heated washing water, out of the dish washing machine. 
         [0036]    As shown in  FIGS. 3 and 4 , the component for exhausting air inside the washing machine includes an exhaust fan  390  for suctioning high-temperature wet air from the tub  150 , a housing  394  defining a space for receiving the exhaust fan  390 , and an exhaust duct  392  for guiding the high-temperature wet air, suctioned by the exhaust fan  390 , out of the dish washing machine. 
         [0037]    Further, the exhaust fan  390  may be a bidirectional suction fan. Specifically, the exhaust fan  390  suctions the high-temperature wet air from the tub  150  into the housing  394 , and, at the same time, suctions low-temperature, low-humidity air from the outside into the exhaust duct  392 , such that the condensation of moisture is performed in the housing  394  or the exhaust duct  392 . 
         [0038]    Consequently, the amount of moisture contained in the exhausted air is reduced, and the temperature of the exhausted air is also lowered. Accordingly, the formation of moisture on the installation surface of the dish washing machine and the walls of the furniture installed adjacent to the dish washing machine are minimized. 
         [0039]    Of course, the present invention is not limited to the above-described construction. For example, the exhaust fan  390  according to an embodiment of the present invention may be configured to suction and exhaust only the air in the tub  150 . Further, the exhaust duct  392  may be coupled to one side of the housing  394  such that the exhaust duct  392  communicates with the housing  394 . 
         [0040]    Also, as shown in  FIG. 4 , the exhaust duct  392  extends downward through the interior of the door  120  toward the installation surface of the dish washing machine. Consequently, air exhausted from the housing  394  is exhausted to the lower part of the door  120  along the exhaust duct  392 . The exhaust duct  392  also includes ribs  399  for guiding the flow of air exhausted from the exhaust duct  392 . 
         [0041]    Next,  FIG. 5  is a perspective view illustrating the exhaust duct  392  according to an embodiment of the present invention, and  FIG. 6  is a sectional view illustrating the lower end of the exhaust duct of  FIG. 5 . 
         [0042]    As shown in  FIG. 5 , one side of the middle part of the exhaust duct  392  includes a water recovering hole  393 , which communicates with the tub  150  for recovering water flowing in the exhaust duct  392  to the tub  150 . As shown in  FIGS. 5 and 6 , the exhaust duct also includes a first bent part  397  such that a lower end  391  of the exhaust duct  392  is inclined at a predetermined angle with respect to the installation surface of the dish washing machine. 
         [0043]    In addition, the first bent part  397  is formed adjacent to the lower end  391  of the exhaust duct  392 . Consequently, the lower end  391  of the exhaust duct  392  is inclined at the predetermined angle to the installation surface of the dish washing machine such that the lower end  391  of the exhaust duct  392  is directed in the direction in which the door  120  is directed (i.e., the direction in which the door  120  is opened). 
         [0044]    Further, one reason why the lower end  391  of the exhaust duct  392  is directed in the direction in which the door  120  is directed is as follows. When the dish washing machine is installed in a built-in structure, the opposite sides of the dish washing machine are closed by the sides of the kitchen furniture “f” (see  FIG. 2 ), the rear of the dish washing machine is also closed by the wall, and an open space for opening and closing the door  120  is formed at the front of the dish washing machine. Therefore, the lower end  391  of the exhaust duct  392  is directed to the open space in the direction in which the door  120  is directed such that air exhausted from the exhaust duct  392  is exhausted toward the open space, 
         [0045]    As described above, the exhaust duct  392  is mounted in the door  120 . In addition, the door  120  includes various parts, such as a frame for maintaining the strength of the door  120  and a noise isolation member for isolating noise. As a result, the interior space of the door  120  is limited. Consequently, as shown in  FIG. 6 , the exhaust duct  392  is mounted in the door  120 , such that the exhaust duct  392  is in tight contact with the inside of a panel  122  constituting the front of the door  120 , for maximum spatial utilization. 
         [0046]    However, when the exhaust duct  392  having the first bent part  397  is mounted in the door  120  such that the exhaust duct  392  is in tight contact with the inside of the panel  122 , the lower end  391  of the exhaust duct  392  protrudes outward from the front of the dish washing machine by the first bent part  397 , which reduces the aesthetical appearance of the dish washing machine. 
         [0047]    Consequently, as shown in  FIGS. 5 and 6 , the exhaust duct  392  preferably includes a second bent part  398  at the exhaust duct  392  such that the inclined lower end  391  of the exhaust duct  392  is located in the door  120  of the dish washing machine. In addition, the second bent part  398  is formed at the upper side of the first bent part  397  of the exhaust duct  392 . In more detail, the second bent part  398  is bent at least once in the rearward direction of the door  120 , which is opposite to the direction in which the first bent part  397  is bent. Consequently, the first bent part  397 , which is inclined to be directed toward the door  120 , does not protrude outward from the dish washing machine, thereby increasing the aesthetical appearance of the dish washing machine. 
         [0048]    That is, the exhaust duct  392  is formed such that the second bent part  398  is bent in the direction opposite to the direction in which the door  120  is opened, and the first bent part  397  is bent in the direction in which the door is opened. 
         [0049]    In addition, the present invention is not limited to the above-described construction. For example, when the inner space of the door  120  is sufficient, the exhaust duct  392  may be spaced by the protruding length of the inclined lower end  391  of the exhaust duct  392  from the panel  122  constituting the front of the door  120 . 
         [0050]    In addition, as discussed above, the exhaust duct  392  shown in  FIG. 4  includes the ribs  399  for guiding the flow of air exhausted from the exhaust duct  392 . That is, one or more ribs  399  are preferable formed at the lower end  391  of the exhaust duct  392 . The ribs  399  are also preferably inclined such that exhausted air flows not toward the sides of the dish washing machine, but toward a vertical center line C of the door  120  as shown in  FIG. 4 . 
         [0051]    That is, as shown in  FIG. 4 , the vertical center line C of the door  120  is an imaginary perpendicular line drawn perpendicularly to the installation surface at the outer middle part of the door  120 . In addition, the ribs  399  being inclined minimizes the contact of the air exhausted from the exhaust duct  392  with the sides of the kitchen furniture located at the sides of the dish washing machine. 
         [0052]    In addition, the present invention is not limited to the above-described construction. For example, the lower end of the exhaust duct may be inclined toward the vertical center line of the door. 
         [0053]    Meanwhile, as shown in  FIG. 4 , the exhaust duct  392  is mounted in the door  120 , and preferably, the exhaust duct  392  is mounted in the door  120  such that the exhaust duct  392  is deviated to the left side or the right side when viewed from the front. The following description will be given on the assumption that the exhaust duct  392  is deviated to the left side. 
         [0054]    In more detail, to reduce the flow loss of the air flowing in the exhaust duct  392 , and as shown in  FIGS. 4 and 5 , the exhaust duct  392  is preferably formed such that the air is gradually diffused during the flow of the air in the exhaust duct  392 . In addition, a sectional area of the exhaust duct  392  is gradually widened so the air is diffused in the exhaust duct. 
         [0055]    Also, when the exhaust pressure of the air exhausted from the exhaust duct  392  is too low, the air is mixed with external air, the air is not sufficiently exhausted out of the dish washing machine, and is then diffused toward the bottom, the installation surface, and the sides of the dish washing machine. Consequently, an appropriate exhaust pressure is preferred. 
         [0056]    In more detail, an appropriate exhaust pressure is related to the distance between the lower end  391  of the exhaust duct  392  and the outer surface of the door  120  of the dish washing machine, the sectional area and shape of the exhaust duct  392 , and the blowing pressure of the exhaust fan  390 . However, these factors may be changed depending upon the size or model of the dish washing machine. 
         [0057]    As previously described, the frame for maintaining the strength of the door and various components for noise isolation and watertightness are mounted in the door  120 , with the result that the inner space of the door  120  is very small. Consequently, the cross section of the exhaust duct  392  is preferably gradually lowered along the downward direction of the exhaust duct  392 , whereas the width of the exhaust duct  392  is gradually increased along the downward direction of the exhaust duct  392 , to avoid interference with the components and to diffuse the air flowing in the exhaust duct  392 . 
         [0058]    Specifically, the cross section of an inlet end of the exhaust duct  392 , which is coupled to the housing  394 , is higher than the cross section of the lower end  391  of the exhaust duct  392  through which air is exhausted. Also, the width of the inlet end of the exhaust duct  392  coupled to the housing  394  is greater than the width of the lower end  391  of the exhaust duct  392  through which air is exhausted. 
         [0059]    In addition, as shown in  FIG. 5 , the exhaust duct  392  is also preferably formed in a structure in which the exhaust duct  392  has a step part  395  at least once such that the cross section of the exhaust duct  392  is gradually decreased along the downward direction of the exhaust duct  392 . 
         [0060]    In addition, the step part  395  is preferably formed to avoid interference with the components mounted in the door  120 . Also, the step part  395  may be formed to serve as a guide  396  for guiding the water flowing in the exhaust duct  392  to the water recovering hole  393  along the step part  395 . 
         [0061]    In addition, when the step part  395  is formed to serve as the guide  396 , the top of the step part  395  is preferably formed to be inclined downward toward the water recovering hole  393 . Specifically, the water flowing along the inside of the exhaust duct  392  is guided to the water recovering hole  393  along the guide  396  of the step part  395 . 
         [0062]    As previously described, the cross section of the exhaust duct  392  is gradually lowered along the downward direction of the exhaust duct  392 , whereas the width of the exhaust duct  392  is gradually increased along the downward direction of the exhaust duct  392 . 
         [0063]    Further, the side (i.e., the right side) of the exhaust duct  392  facing the imaginary vertical center line C of the door  120  of the right and left sides of the exhaust duct  392  is preferably gradually inclined toward the vertical center line C of the door  120  along the downward direction of the exhaust duct  392 . 
         [0064]    Also, the side (i.e., the left side) of the exhaust duct  392  opposite to the side of the exhaust duct  392  facing the vertical center line C of the door  120  of the right and left sides of the exhaust duct  392  is preferably substantially formed perpendicularly to the installation surface. In addition, the point where the right side of the exhaust duct  392  starts to be inclined may be located above the middle height of the exhaust duct  392 . 
         [0065]    Further, because the right side of the exhaust duct  392  is inclined toward the vertical center line C of the door  120 , and the left side of the exhaust duct  392  is substantially formed vertically, the width of the exhaust duct  392  is gradually increased along the downward direction of the exhaust duct  392 . Consequently, the air flowing in the exhaust duct  392  is gradually diffused during the movement of the air to the lower end  391  of the exhaust duct  392 , whereby flow loss or noise is reduced. 
         [0066]    Also, the air exhausted from the exhaust duct  392  has inertia in which the air will diffuse in the exhaust duct  392 . Consequently, the air exhausted from the exhaust duct  392  is exhausted toward the vertical center line C of the door  120 , and therefore, the formation of moisture on the sides of the furniture located at the sides of the dish washing machine is minimized. 
         [0067]    Consequently, the air in the tub of the dish washing machine according to an embodiment of the present invention is exhausted outside through the following process. In more detail, when the exhaust fan  390  is operated, high-temperature, high-humidity air in the tub  150  is suctioned into the housing  394  and is guided to the exhaust duct  392  by the exhaust fan  390 . 
         [0068]    In addition, the side of the exhaust duct  392  facing the vertical center line C of the door  120  is inclined in the direction in which the exhaust duct  392  is widened. Consequently, the air flowing in the exhaust duct  392  is diffused in the direction in which exhaust duct  392  is widened, whereby flow loss or noise is reduced. 
         [0069]    Meanwhile, moisture contained in the air is condensed in the exhaust duct  392  such that condensed water flows in the exhaust duct  392 . Further, the condensed water flows along the inside of the exhaust duct  392 , is guided to the water recovering hole  393  along the guide  396  formed at the step part  395 , and is collected in the tub  150 . 
         [0070]    Also, the flow direction of air in the exhaust duct  392  is bent at the second bent part  398  of the exhaust duct  392  in the direction opposite to the direction in which the door is directed, and is bent at the first bent part  397  of the exhaust duct  392  in the direction in which the door is directed, i.e., in the opening direction of the door. Consequently, the air is exhausted from the exhaust duct  392  toward the front of the dish washing machine such that the flow direction of the air is at a predetermined angle to the installation surface. 
         [0071]    In addition, because the ribs  399  are formed at the lower end  391  of the exhaust duct  392 , the air is exhausted toward the vertical center line C of the door  120 . As a result, the air is smoothly exhausted out of the dish washing machine without contact of the air with the furniture located at the sides of the dish washing machine. 
         [0072]    As apparent from the above description, the present invention has several advantages. 
         [0073]    First, the air exhausted from the exhaust duct is directed in the opening direction of the door, and therefore, the air flows toward the open front of the dish washing machine. Consequently, the air is smoothly exhausted out of the dish washing machine without the introduction of the air to the sides and the rear of the dish washing machine, whereby the formation of moisture on the installation surface of the dish washing machine is minimized. In addition, the high-temperature air is smoothly exhausted out of the dish washing machine, and therefore, the deformation of the installation surface of the dish washing machine due to heat is minimized. 
         [0074]    Secondly, the air exhausted from the exhaust duct flows toward the vertical center line of the door of the dish washing machine. Consequently, the flow of the air exhausted from the exhaust duct to the sides of the dish washing machine is prevented, whereby it is possible to solve the problems which may occur due to the contact of the high-temperature, high-humidity exhausted air with the walls of kitchen furniture installed at the sides of the dish washing machine. 
         [0075]    It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.