Abstract:
A dish washing machine capable of improving spatial utilization of a washing tub through the enlargement of the washing tub. The dish washing machine includes a washing tub, a sump mounted in the washing tub to receive and pump wash water, a sump housing forming an external appearance of the sump, a washing impeller to pump wash water from the sump housing, a drainage channel disposed at an inner edge of the sump housing, a pump motor surrounded by the drainage pump to drive the washing impeller, and a pump motor receiving part to receive the pump motor. The pump motor receiving part protrudes above the drainage channel.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. application Ser. No. 11/806,520, filed May 31, 2007, which in turn claims the benefit of Korean Patent Application No. 10-2006-0065596, filed on Jul. 12, 2006 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    The present invention relates to a dish washing machine. More particularly, to a dish washing machine capable of improving spatial utilization of a washing tub through the enlargement of the washing tub. 
         [0004]    2. Description of the Related Art 
         [0005]    A conventional dish washing machine is a machine that automatically washes dishes using cold water or hot water. A conventional dish washing machine includes a machine body, a washing tub formed in the machine body, baskets mounted in the washing tub, and main and sub nozzles mounted at the upper part, the middle part, and the lower part of the washing tub to inject wash water, which is disclosed in Korean Unexamined Patent Publication No. 2005-54700. 
         [0006]    A sump is mounted at the bottom of the washing tub to receive wash water and pump the wash water to the respective nozzles. The sump includes a sump housing forming the external appearance of the sump, a heater mounted in the sump housing, a washing impeller disposed in the sump housing to pump wash water, a channel to guide the wash water pumped from the washing impeller to the respective nozzles, a channel control valve mounted in the channel to control the flow of wash water, and a pump motor mounted at the outside of the sump housing to drive the washing impeller. 
         [0007]    In the conventional dish washing machine, however, the heater is mounted in the sump housing such that the height of the sump housing is increased. Furthermore, the pump motor is mounted at the bottom of the sump housing such that the height of an assembly of the sump and the pump motor is increased. 
         [0008]    Consequently, a ratio of the height of the sump and pump motor assembly to the height of the machine body of the dish washing machine is increased, and therefore, the space of the washing tub is relatively reduced. 
       SUMMARY OF THE INVENTION 
       [0009]    Accordingly, it is an aspect of the present invention to provide a dish washing machine capable of reducing the height of a sump and pump motor assembly and, at the same time, enlarging the space of a washing tub, thereby improving spatial utilization of the washing tub. 
         [0010]    Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the invention. 
         [0011]    The foregoing and/or other aspects of the present invention are achieved by providing a dish washing machine including a washing tub, a sump mounted in the washing tub to receive and pump wash water, a sump housing forming an external appearance of the sump, a washing impeller to pump wash water from the sump housing, a drainage channel disposed at an inner edge of the sump housing, a pump motor surrounded by the drainage pump to drive the washing impeller, and a pump motor receiving part to receive the pump motor, the pump motor receiving part protruding above the drainage channel. 
         [0012]    According to an aspect of the present invention, the pump motor receiving part is formed at a bottom of the sump housing, and the pump motor receiving part includes an open lower part, through which the pump motor is inserted into and mounted to the pump motor receiving part. 
         [0013]    The pump motor includes screw insertion holes formed in an edge thereof such that screws are inserted through the screw insertion holes, and the pump motor receiving part includes screw coupling protrusions protruding therefrom such that the screws inserted through the screw insertion holes are coupled to the screw coupling protrusions. 
         [0014]    The dish washing machine further includes a heater disposed in a shape surrounding the sump. 
         [0015]    The dish washing machine further includes a heater receiving groove formed at the bottom of the washing tub in a shape surrounding the sump such that the heater is received in the heater receiving groove, and a heater cover disposed at the heater receiving groove to cover the heater, the heater cover having a plurality of through-holes, through which wash water contacts the heater. 
         [0016]    The dish washing machine further includes main nozzles disposed in the washing tub to constantly inject wash water at the time of washing dishes, a sub nozzle disposed in the washing tub to selectively inject wash water at the time of washing dishes, a main channel disposed in the sump, the main channel communicating with the main nozzles, a sub channel disposed in the sump while being separated from the main channel, the sub channel communicating with the sub nozzle, and a channel control valve disposed in the sub channel to selectively intermit the flow of wash water flowing to the sub nozzle. 
         [0017]    The dish washing machine further includes an impeller casing to receive the washing impeller, and an impeller casing cover disposed on the impeller casing to cover the impeller casing, the impeller casing cover having a guide channel communicating with the sub channel to guide the wash water to the sub nozzle. 
         [0018]    The impeller casing includes a filth chamber communicating with the main channel to collect dirt contained in wash water. 
         [0019]    The filth chamber includes an open upper part, and the dish washing machine further includes a mesh filter disposed at the open upper part of the filth chamber to separate dirt from wash water such that only the wash water overflows from the filth chamber. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: 
           [0021]      FIG. 1  is a side sectional view of a dish washing machine according to an embodiment of the present invention; 
           [0022]      FIG. 2  is a perspective view illustrating an interior of a machine body of the dish washing machine according to an embodiment of the present invention; 
           [0023]      FIG. 3  is an exploded perspective view of a sump according to an embodiment of the present invention; 
           [0024]      FIG. 4  is an exploded perspective view of a sump housing and a pump motor according to an embodiment of the present invention; 
           [0025]      FIGS. 5 and 9  are assembled views of the sump housing and the pump motor according to an embodiment of the present invention; 
           [0026]      FIG. 6  is a perspective view illustrating the upper part of the sump according to an embodiment of the present invention; 
           [0027]      FIG. 7  is a perspective view illustrating the upper part of the sump housing according to an embodiment of the present invention; and 
           [0028]      FIG. 8  is an assembled perspective view of the sump housing and an impeller casing according to an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0029]    Reference will now be made in detail to the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below to explain the present invention by referring to the figures. 
         [0030]    As shown in  FIG. 1 , the dish washing machine comprises a machine body  1  forming, an external appearance of the dish washing machine, a washing tub  2  disposed in the machine body  1 , and a rack  5  fixed to a sidewall of the washing tub  2 . The rack  5  comprises an upper rack  5   a  and a lower rack  5   b , by which an upper basket  7   a  and a lower basket  7   b  are supported, respectively. Dishes are placed in the upper basket  7   a  and the lower basket  7   b.    
         [0031]    At the upper part, the middle part, and the lower part of the washing tub  2  are mounted main nozzles  10   a  and  10   b  and a sub nozzle  10   c , respectively, to inject wash water. The wash water injected through the nozzles  10   a ,  10   b  and  10   c  is directed toward the baskets  7   a  and  7   b . The nozzles  10   a ,  10   b  and  10   c  are rotated by the injection pressure of the wash water injected through the nozzles  10   a ,  10   b  and  10   c . The wash water injected through the nozzles  10   a ,  10   b , and  10   c  collides with the dishes in the baskets  7   a  and  7   b  to strongly wash the dishes. 
         [0032]    A sump  13  is mounted at the bottom of the washing tub  2  to receive, pump, and supply wash water to the respective nozzles. 
         [0033]    A feeding pipe  11  is disposed at a rear of the washing tub  2  to supply wash water to the main nozzles  10   a  and  10   b . The lower end of the feeding pipe  11  is connected to the sump  13 . Consequently, the wash water flows to the main nozzles  10   a  and  10   b  through the feeding pipe  11  due to strong pumping pressure of the sump  13 . 
         [0034]    The sub nozzle  10   c  is directly connected with an upper center part of the sump  13 . Consequently, some of the wash water is injected through the sub nozzle  10   c  to wash dishes placed in the lower basket  7   b  adjacent to the sub nozzle  10   c.    
         [0035]    When the quantity of dishes is relatively small, the dishes may be placed only in the upper basket  7   a , and wash water be injected only through the main nozzles  10   a  and  10   b  while the wash water is not injected through the sub nozzle  10   c , and vice versa. 
         [0036]    The sump  13  comprises a sump housing  16  forming the external appearance of the sump, a sump cover  19  to cover the sump housing  16 , a washing impeller  21  disposed in the sump housing  16 , an impeller casing  24  to which the washing impeller  21  is mounted, and an impeller casing cover  27  disposed on the impeller casing  24 . 
         [0037]    A pump motor  30  is mounted at the bottom of the sump housing  16  to drive the washing impeller  21 . Specifically, a pump motor receiving part  300  is disposed at the bottom of the sump housing  16  such that the pump motor  30  is received in the pump motor receiving part  300 . 
         [0038]    The pump motor  30  is securely coupled with the sump housing  16  by means of screws. However, the present invention is not limited hereto and other coupling members may used to accomplish the coupling between the pump motor  30  and the sump housing  16 . 
         [0039]    As shown in the drawings, the lower part of the sump  13  overlaps with the upper part of the pump motor  30  by a predetermined height. 
         [0040]    Thus, a height of an assembly of the sump  13  and the pump motor  30  is reduced by the overlap. The decrease of the height of the sump and pump motor assembly leads to the relative increase of the vertical height of the washing tub  2 . 
         [0041]    A drainage pump  33  is mounted at the side of the sump housing  16  to discharge wash water and dirt in the sump  13  out of the dish washing machine. 
         [0042]    A heater  36  is mounted at an edge of the sump  13  to heat wash water. At the bottom of the washing tub  2  is formed a heater receiving groove  39 , which extends along the edge of the sump  13 . The heater  36  is received in the heater receiving groove  39 . 
         [0043]    After the heater  36  is received in the heater receiving groove  39 , the heater  36  is covered by a heater cover  42  to prevent the heater  36  from being exposed to the outside. 
         [0044]    In  FIG. 2 , an inlet port  3  is formed through one side of the washing tub  2  such that wash water can be introduced into the washing tub  2  through the inlet port  3 . Wash water introduced through the inlet port  3  falls to the bottom of the washing tub  2  and is introduced into the sump  13 . 
         [0045]    The sub nozzle  10   c  is rotatably coupled to a center of the sump  13 . The feeding pipe  11  is connected with a rear end of the sump  13  such that wash water is guided to the main nozzles  10   a  and  10   b  through the feeding pipe  11 . 
         [0046]    The sump cover  19  is mounted on the sump  13 . Inlet holes  19   a  are formed along an edge of the sump cover  19  and are arranged in regular intervals. Consequently, wash water is introduced into the sump  13  through the inlet holes  19   a.    
         [0047]    On the sump cover  19  is mounted a filter cover  20 . A mesh filter  20   a  is mounted to the filter cover  20  to prevent dirt collected in a filth chamber (to be described later), from overflowing from the filth chamber and to allow only wash water to flow out of the filth chamber. 
         [0048]    The heater  36  is mounted at an edge of the sump  13  in the shape of a ring. The heater cover  42  is mounted on the heater  36 . A plurality of through-holes  42   a , through which wash water flows to the heater  36 , are defined through the heater cover  42 . The wash water is heated by the heater  36 , and is then introduced into the sump  13 . 
         [0049]      FIG. 3  illustrates the structure of the sump  13 , according to an embodiment of the present invention. At one side of the sump housing  16  is disposed a pump fixing part  50 , to which the drainage pump  33  is fixed. To one side of the pump fixing part  50  is connected a drainage pipe  51 , through which wash water and filth are discharged. 
         [0050]    The pump motor  30  is mounted at the bottom of the sump housing  16 , specifically, to the pump motor receiving part  300 . Around the pump motor receiving part  300  (shown in  FIGS. 1 and 4 , for example) is disposed a drainage channel  160 , which surrounds the pump motor receiving part  300 . The drainage channel  160  comprise first, second, and third drainage channels  161 ,  162 , and  163  surrounding the pump motor receiving part  300 . The first and second drainage channels  161  and  162  communicate with each other through the third drainage channel  163 , which serves to guide wash water and filth to the drainage pump  33 . 
         [0051]    The top surface of the pump motor receiving part  300  is located above the bottom surface of the drainage channel  160 . 
         [0052]    Consequently, the pump motor  30  is received in the pump motor receiving part  300  without reduction of the wash water and filth discharge operation through the drainage channel  160 , and therefore, the height of the sump and pump motor assembly is considerably reduced. 
         [0053]    A rotary shaft  30   a  of the pump motor  30  extends through the pump motor receiving part  300 . At the pump motor receiving part  300  is disposed a sealing member  53 , which surrounds the rotary shaft  30   a  to prevent wash water from leaking to the pump motor  30 . 
         [0054]    The impeller casing  24  is disposed on the sump housing  16 . A communication hole  24   a  is formed in a center of the impeller casing  24  and communicates with the sump housing  16 . Around the communication hole  24   a  is disposed an impeller receiving part  24   b , in which the washing impeller  21  is received. 
         [0055]    The washing impeller  21  is coupled with the rotary shaft  30   a  of the pump motor  30  such that the washing impeller  21  is rotated to pump wash water introduced into the sump housing  16  upward. 
         [0056]    The impeller casing  24  comprises a main channel  24   c  and a sub channel  24   d , which diverge from the impeller receiving part  24   b . The main channel  24   c  guides wash water to the main nozzles  10   a  and  10   b  (see  FIG. 1 ). The sub channel  24   d  guides wash water to the sub nozzle  10   c  (see  FIG. 1 ). 
         [0057]    The main channel  24   c  serves as a primary channel to guide the flow of wash water in the sump  13 . Consequently, wash water constantly passes along the main channel  24   c  during a washing operation of the dish washing machine. 
         [0058]    The main channel  24   c  extends from the impeller receiving part  24   a  in a shape of a curve, to prevent drop of the injection pressure of wash water flowing along the main channel  24   c.    
         [0059]    When the main channel  24   c  is sharply bent, wash water collides with the sharply bent part of the main channel  24   c  with the result that kinetic energy of the wash water is lost. Consequently, the main channel  24   c  is formed in the shape of a curve to minimize the loss of kinetic energy. 
         [0060]    A channel control valve  25  is rotatably mounted in the sub channel  24   d  to intermit the flow of wash water to the sub channel  24   d . When the quantity of dishes to be washed is small, the sub channel  24   d  is closed by the channel control valve  25  such that wash water can flow only to the main channel  24   c.    
         [0061]    Wash water flowing along the main channel  24   c  is injected through the main nozzles  10   a  and  10   b  (see  FIG. 1 ) to wash dishes. Consequently, the amount of wash water used is reduced when the quantity of dishes to be washed is small. 
         [0062]    A filth chamber  24   e  is formed beside the main channel  24   c  to collect dirt introduced into the main channel  24   c  together with wash water. A drainage connection pipe  26  is mounted adjacent to the inlet of the filth chamber  24   e , which is connected to the drainage pump  33 . When the drainage pump  33  is operated, dirt collected in the filth chamber  24   e  is discharged to the drainage pipe  51  through the drainage connection pipe  26 . 
         [0063]    According to an embodiment of the present invention, the main channel  24   c , the sub channel  24   d , and the filth chamber  24   e  are formed at the impeller casing  24 . 
         [0064]    The impeller casing cover  27  is disposed on the impeller casing  24 . The impeller casing cover  27  comprises a guide channel  27   a , which communicates with the sub channel  24   d . The guide channel  27   a  extends from an edge of the impeller casing cover  27  to the center of the impeller casing cover  27  in a shape of a curve. 
         [0065]    Consequently, when the sub channel  24   d  is opened by the channel control valve  25 , wash water pumped by the washing impeller  21  passes through the channel control valve  25 , and flows along the sub channel  24   d . At this time, the wash water is guided to the sub nozzle  10   c  (see  FIG. 1 ) along the guide channel  27   a , which communicates with the sub channel  24   d , and is then injected through the sub nozzle  10   c.    
         [0066]    The sump cover  19  is disposed on the impeller casing cover  27 . In the center of the sump cover  19  is formed an engaging hole  19   c , in which the lower end of the sub nozzle  10   c  (see  FIG. 1 ) is engaged. The inlet holes  19   a , through which wash water is introduced, are formed along the edge of the sump cover  19  such that the inlet holes  19   a  are arranged in regular intervals. 
         [0067]    In the sump cover  19  is formed a connection hole  19   b , through which the feeding pipe  11  (see  FIG. 2 ) extends to the main channel  24   c.    
         [0068]    The filter cover  20  is disposed on the sump cover  19 . The mesh filter  20   a  is mounted to the filter cover  20 . The mesh filter  20   a  covers an upper surface of the filth chamber  24   e  to prevent dirt collected in the filth chamber  24   e  from passing through the mesh filter  20   a  together with wash water. 
         [0069]    Specifically, when dirt and wash water are introduced into the filth chamber  24   e , the wash water passes through the mesh filter  20   a . However, the dirt is filtered by the mesh filter  20   a  and is left in the filth chamber  24   e.    
         [0070]    The wash water separated from the dirt is introduced into the sump  13  through the inlet holes  19   a , and is then continuously circulated through the above-described course. 
         [0071]    The heater  36  (see  FIG. 2 ) and the heater cover  42  are disposed at the edge of the sump  13  such that the heater  36  and the heater cover  42  surround the edge of the sump  13 . 
         [0072]    As shown in  FIG. 4 , the pump motor receiving part  300  is disposed in the center of the sump housing  16 . Screw coupling protrusions  16   a  are formed at the pump motor receiving part  300  and protrude downward from the pump motor receiving part  300 . 
         [0073]    The first, second, and third drainage channels  161 ,  162 , and  163  are formed around the pump motor receiving part  300 . The drainage channel  160  is disposed below the pump motor receiving part  300 . 
         [0074]    Screw insertions holes  30   a  are formed in an edge of the pump motor  30  corresponding to the screw coupling protrusions  16   a.    
         [0075]    When screws  31  are inserted through the screw insertion holes  30   a  and coupled with the screw coupling protrusions  16   a , as shown in  FIG. 5 , the pump motor  30  is surrounded by the drainage channels  161 ,  162 , and  163  while the pump motor  30  is received in the pump motor receiving part  300 . 
         [0076]    The pump fixing part  50  is disposed at one side of the sump housing  16 . The drainage pump  33  is fixed to the pump fixing part  50 . At the sump housing  16  is mounted a sensor  170  to detect the turbidity and the water level of wash water received in the sump housing  16 . The drainage pump  33  discharges wash water and dirt out of the sump housing  16  based on information detected by the sensor  170 . 
         [0077]    At the bottom of the sump housing  16  is mounted a valve driving motor  62  to drive the channel control valve (not shown) such that the sub channel (not shown) can be opened or closed by the channel control valve 
         [0078]    As shown in  FIG. 6 , wash water is heated by the heater  36 , and is then introduced into the sump  13 . As shown in  FIG. 7 , the wash water received in the sump housing  16  is pumped upward to the impeller casing  24  as the washing impeller  21  mounted to the rotary shaft is rotated. 
         [0079]    The pumped wash water is moved from the impeller receiving part  24   b  to the main channel  24   c  (in the direction indicated by arrow ‘A’) and the sub channel  24   d  (in the direction indicated by arrow ‘B’) due to the rotating force of the washing impeller. When the sub channel  24   d  is closed by the channel control valve  25 , the wash water is moved only to the main channel  24   c.    
         [0080]    The wash water flowing along the main channel  24   c  in the direction indicated by arrow ‘A’ is raised through the feeding pipe  11  (see  FIG. 2 ), due to the strong pressure of the washing impeller  21 , and then reaches the main nozzles  10   a  and  10   b  (see  FIG. 1 ). 
         [0081]    When the quantity of dishes to be washed is small, and therefore, it is necessary to operate only the main nozzles  10   a  and  10   b  (see  FIG. 1 ), the sub channel  24   d  is closed by the channel control valve  25 . As a result, wash water flows along only the main channel  24   c . The wash water flowing along the main channel  24   c  reaches the main nozzles  10   a  and  10   b  through the feeding pipe  11 , and is then injected through the main nozzles  10   a  and  10   b.    
         [0082]    When the quantity of dishes to be washed is large, and therefore, it is necessary to operate the sub nozzle  10   c  (see  FIG. 1 ) as well as the main nozzles  10   a  and  10   b , the sub channel  24   d  is opened by the channel control valve  25 . As a result, wash water flows in the direction indicated by arrow B. Subsequently, the wash water reaches the sub nozzle  10   c , and is then injected through the sub nozzle  10   c.    
         [0083]    The filth chamber  24   e  is connected to the main channel  24   c . Consequently, dirt mixed with some wash water is moved (in the direction indicated by arrow ‘C’), and is then collected in the filth chamber  24   e.    
         [0084]    The drainage connection pipe  26  connected to the drainage pump  33  is adjacent to the inlet of the filth chamber  24   e . Consequently, the dirt collected in the filth chamber  24   e  is discharged to the outside (in the direction indicated by arrow ‘D’) during an operation of the drainage pump  33 . 
         [0085]    As shown in  FIG. 8 , the guide channel  27   a  is formed at the impeller casing cover  27  disposed on the impeller casing  24  such that the guide channel  27   a  communicates with the sub channel  24   d  (see  FIG. 7 ) 
         [0086]    When the washing impeller  21  (see  FIG. 7 ) is operated in the state that the sub channel  24   d  is opened by the channel control valve  25  (see  FIG. 7 ), wash water also flows along the sub channel  24   d . The wash water flowing along the sub channel  24   d  is guided to the center of the impeller casing cover  27  along the guide channel  27   a , is moved to the sub nozzle  10   c  (see  FIG. 1 ) in the direction indicated by arrow ‘A’, and is injected through the sub nozzle  10   c.    
         [0087]    Arrow ‘B’ indicates the flow direction of the wash water flowing to the main nozzles  10   a  and  10   b  (see  FIG. 1 ). 
         [0088]    As shown in  FIG. 9 , wash water and dirt introduced into the filth chamber  24   e  (see  FIG. 7 ) along the main channel  24   c  (see  FIG. 7 ) are pushed toward the mesh filter  20   a  due to the pressure of subsequent wash water. However, the dirt does not pass through the mesh filter  20   a . Consequently, the dirt is left in the filth chamber  24   e  (see  FIG. 7 ). Only the wash water passes through the mesh filter  20   a  in the direction indicated by arrow ‘E’, and is then discharged out of the sump  13 . 
         [0089]    The discharged wash water is reintroduced into the sump  13 , and flows inside the sump  13  to perform the washing operation as previously described. 
         [0090]    As apparent from the above description, according to an embodiment of the present invention, the pump motor is mounted to the sump housing while the pump motor is received in the sump housing. Consequently, a height of the sump and pump motor assembly is reduced by the height of the pump motor received in the sump housing, and therefore, a ratio of the volume of the washing tub to the volume of the machine body is increased. 
         [0091]    Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.