Patent Publication Number: US-2023148829-A1

Title: Dishwasher

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application PCT/KR2021/007807, filed Jun. 22, 2021, and claims foreign priority to Korean application 10-2020-0090722, filed Jul. 22, 2020. 
    
    
     BACKGROUND 
     1. Field 
     The present disclosure relates to a dishwasher, and more particularly, to a dishwasher including an improved water tank structure. 
     2. Description of Related Art 
     In general, a dishwasher is a device for washing and drying stored dishes by spraying washing water at a high pressure. The dishwasher operates such that washing water is sprayed at a high pressure into a washing chamber in which the dishes are stored, and the sprayed washing water comes into contact with the dishes to wash foreign substances such as food waste on a surface of the dishes. 
     Particularly, the dishwasher includes a tub in which a washing chamber is formed and a sump mounted on a bottom of the tub to store washing water. Washing water is moved to a spray nozzle by a pumping action of a sump pump mounted inside the sump, and the washing water moved to the spray nozzle is sprayed at a high pressure through a spray hole formed at an end of the spray nozzle. The washing water sprayed at a high pressure hits a surface of the dishes, and foreign substances, such as food waste, on the dishes falls to the bottom of the tub. 
     The dishwasher is provided with a water tank that delivers the supplied washing water to the sump. A regenerator chamber supplying water to a regenerator may be provided in the water tank. At this time, it is required to store more than a certain amount of water in the regenerator chamber for the operation of the regenerator. 
     SUMMARY 
     One aspect of the present disclosure provides a dishwasher including a water softener to which a filter is mountable, a regenerator, and a water tank including a soft water chamber configured to receive water softened by the water softener as soft water, and to store the received soft water, and a regeneration water chamber configured to receive soft water stored in the soft water chamber from the soft water chamber, store the soft water received from the soft water chamber, and supply soft water stored in the regeneration water chamber to the regenerator to regenerate the filter while the filter is mounted to the water softener. 
     The water tank may further include a communication flow path connecting the soft water chamber to the regeneration water chamber so as to allow soft water stored in the soft water chamber to flow from the soft water chamber to the regeneration water chamber. 
     The communication flow path may be formed in a middle of the water tank to allow soft water stored in the soft water chamber to flow to the regeneration water chamber after the soft water chamber is filled with soft water. 
     The water tank may further include a water tank case forming an exterior of the water tank. The communication flow path may be recessed on one surface of the water tank case. 
     The water tank may further include a first flow path wall forming a first flow path receiving water from an outside of the water tank, and a second flow path wall forming a second flow path to supply water from the first flow path to the water softener. The regeneration water chamber may be formed between the first flow path wall and the second flow path wall. 
     The communication flow path may bypass the second flow path wall to extend vertically between the soft water chamber and the regeneration water chamber. 
     The regeneration water chamber may include a pressure holder connected to an outside of the soft water chamber to allow a pressure in the regeneration water chamber to be equilibrated with atmospheric pressure. 
     The pressure holder may allow the soft water chamber and the regeneration water chamber to communicate with each other. 
     The pressure holder may be arranged at an upper portion of the water tank to store water at a high level in the water tank. 
     The water tank may include an inclined rib inclined with respect to a water surface in the water tank. The pressure holder may be formed below the inclined rib. 
     The water tank may include a water tank case forming an exterior of the water tank. The pressure holder may be recessed on one surface of the water tank case. 
     The regenerator may be arranged below the water tank. The water tank may further include a regeneration water inlet valve arranged below the regeneration water chamber to control whether to input water so as to input water, stored in the regeneration water chamber, to the regenerator. 
     In order to prevent water of the soft water chamber from being discharged to the regeneration water chamber, the regeneration water inlet valve may be opened in response to a water level in the soft water chamber being lower than a water level in the regeneration water chamber. 
     The regeneration water inlet valve may be opened in response to the soft water chamber being empty. 
     The water tank may further include a damper provided in the communication flow path so as to adjust an amount of water flowing from the soft water chamber to the regeneration water chamber. 
     Another aspect of the present disclosure provides a dishwasher including a washing chamber, a water tank storing water to supply water to the washing chamber, a water softener connected to the water tank, and a regenerator connected to the water softener to regenerate the water softener. The water tank includes a soft water chamber receiving water, which is softened, from the water softener, and storing the soft water, a regeneration water chamber receiving the soft water from the soft water chamber and connected to the regenerator to supply regeneration water to the regenerator, and a regeneration water inlet valve arranged in the regeneration water chamber to input water, which is stored in the regeneration water chamber, to the regenerator. 
     The regenerator may be arranged below the water tank, and the regeneration water inlet valve may be arranged below the regeneration water chamber to allow the water of the regeneration water chamber to flow to the regenerator. 
     The regeneration water inlet valve may be opened in response to a water level in the soft water chamber being lower than a water level in the regeneration water chamber. 
     The regeneration water inlet valve may be opened in a drying cycle of the dishwasher. 
     The dishwasher may further include a main body and a door rotatably installed on the main body. The regeneration water inlet valve may be opened in response to the door being closed. 
     Additional aspects of various embodiments 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 embodiments. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       Aspects, features, and advantages of embodiments of the present disclosure will be more apparent from the following description taken in conjunction with the accompany drawings, in which: 
         FIG.  1    is a cross-sectional view illustrating a dishwasher according to an embodiment of the present disclosure. 
         FIG.  2    is a perspective view illustrating a water tank assembly mounted on a tub in the dishwasher according to  FIG.  1   , according to an embodiment of the present disclosure. 
         FIG.  3    is an exploded perspective view illustrating a water tank case in the dishwasher according to  FIG.  1   , according to an embodiment of the present disclosure. 
         FIG.  4    is a plan view illustrating a second water tank case in the dishwasher shown in  FIG.  3   , according to an embodiment of the present disclosure. 
         FIG.  5    is a view illustrating a part A in the dishwasher shown in  FIG.  4   , according to an embodiment of the present disclosure. 
         FIG.  6    is a view illustrating a part B of the dishwasher shown in  FIG.  4   , according to an embodiment of the present disclosure. 
         FIG.  7    is a view illustrating water supply and discharge in the dishwasher shown in  FIG.  1   , according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments described in the disclosure and configurations shown in the drawings are merely examples of the embodiments of the disclosure, and may be modified in various different ways at the time of filing of the present application to replace the embodiments and drawings of the disclosure. 
     In addition, the same reference numerals or signs shown in the drawings of the disclosure indicate elements or components performing substantially the same function. 
     Also, the terms used herein are used to describe the embodiments and are not intended to limit and/or restrict the disclosure. The singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. In this disclosure, the terms “including”, “having”, and the like are used to specify features, numbers, steps, operations, elements, components, or combinations thereof, but do not preclude the presence or addition of one or more of the features, elements, steps, operations, elements, components, or combinations thereof. 
     It will be understood that, although the terms first, second, third, etc., may be used herein to describe various elements, but elements are not limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the disclosure, a first element may be termed as a second element, and a second element may be termed as a first element. The term of “and/or” includes a plurality of combinations of relevant items or any one item among a plurality of relevant items. 
     In the following detailed description, the terms of “front”, “rear”, “left”, “right”, and the like may be defined by the drawings, but the shape and the location of the component is not limited by the term. 
     Various embodiments of the present disclosure are directed to providing a dishwasher capable of easily storing and supplying regeneration water. 
     According to various embodiments of the present disclosure, it is possible to smoothly supply regeneration water to a regenerator by using an improved structure in a water tank. 
     Further, various embodiments of the present disclosure are directed to providing a dishwasher capable of smoothly operating a regenerator. 
     The disclosure will be described more fully hereinafter with reference to the accompanying drawings. 
       FIG.  1    is a cross-sectional view illustrating a dishwasher according to one embodiment of the present disclosure.  FIG.  2    is a perspective view illustrating a water tank assembly mounted on a tub in the dishwasher according to  FIG.  1   . 
     As illustrated in  FIGS.  1  and  2   , a dishwasher  1  may include a main body  10  forming an exterior. 
     The dishwasher  1  may include a tub  12  provided inside the main body  10 . The tub  12  may be provided in a substantially box shape. One surface of the tub  12  may be open. That is, the tub  12  may include an opening  12   a.  As an example, a front surface of the tub  12  may be opened. 
     The dishwasher  1  may further include a door  11  configured to open and close the opening  12   a  of the tub  12 . The door  11  may be installed in the main body  10  to open and close the opening  12   a  of the tub  12 . The door  11  may be rotatably installed in the main body  10 . 
     The dishwasher  1  may further include a storage container provided inside the tub  12  to accommodate dishes. The storage container may include a plurality of baskets  51 ,  52 , and  53 . Dishes having a relatively large volume may be accommodated in the plurality of baskets  51 ,  52 , and  53 . However, the types of dishes accommodated in the plurality of baskets  51 ,  52  and  53  are not limited to relatively large-volume dishes. That is, not only relatively large-volume dishes but also relatively small-volume dishes may be accommodated in the plurality of baskets  51 ,  52 , and  53 . 
     The plurality of baskets  51 ,  52  and  53  may include an intermediate basket  52  positioned in a middle portion with respect to a height direction of the dishwasher  1 , and a lower basket  51  positioned in a lower portion with respect to the height direction of the dishwasher  1 . The intermediate basket  52  may be provided to be supported by an intermediate guide rack  13   a,  and the lower basket  51  may be provided to be supported by a lower guide rack  13   b.  The intermediate guide rack  13   a  and the lower guide rack  13   b  may be installed on a side surface  12   d  of the tub  12  so as to be slidable toward the opening  12   a  of the tub  12 . The side surface  12   d  of the tub  12  may include a right inner surface of the tub  12  and a left inner surface of the tub  12 . 
     The plurality of baskets  51 ,  52  and  53  may include an upper basket  53  positioned in an upper portion with respect to the height direction of the dishwasher  1 . The upper basket  53  may be formed in a rack assembly type to accommodate relatively small-volume dishes. It is appropriate that the upper basket  53  may accommodate a cooking utensil such as a ladle, a knife, or a turner, or cutlery. In addition, the rack assembly may accommodate a small cup such as an espresso cup. However, the kind of dishes accommodated in the upper basket  53  is not limited to the above example. 
     The dishwasher  1  may further include a sump  70  provided to store washing water. The dishwasher  1  may include a washing chamber C formed inside the tub  12 . The washing chamber C is a space in which dishes placed in the baskets  51 ,  52  and  53  are washed by the washing water and dried. 
     The washing chamber C may be defined as an inner space of the tub  12  formed by the front and rear surface, a lower surface  12   b  of the tub, and the sump  70  communicating with the lower surface  12   b.    
     The dishwasher  1  may further include a plurality of spray units  41 ,  42 , and  43  configured to spray washing water. The spray unit may include a first spray unit  41  arranged below the lower basket  51  with respect to the height direction of the dishwasher  1 , a second spray unit  42  arranged below the intermediate basket  52  with respect to the height direction of the dishwasher  1 , and a third spray unit  43  arranged above the upper basket  53  with respect to the height direction of the dishwasher  1 . 
     The first spray unit  41  may be configured to be rotated about a first rotating shaft  41   a,  and the second spray unit  42  may be configured to be rotated about a second rotating shaft  42   a,  and the third spray unit  43  may be configured to be rotated about a third rotating shaft  43   a.    
     However, the disclosure is not limited thereto. The first spray unit  41  may be fixed to one side of the lower surface  12   b  unlike the second spray unit  42  and the third spray unit  43 . In this case, the first spray unit  41  may be configured to spray washing water in a substantially horizontal direction by a fixed nozzle, and the washing water sprayed in the horizontal direction from the nozzle of the first spray unit  41  may be directed to the upper side because a direction of the sprayed water is changed by a switching assembly (not shown). 
     The third spray unit  43  may spray the washing water toward the dishes stored in the upper basket  53 , the intermediate basket  52 , and the lower basket  51 . The second spray unit  42  may spray the washing water toward the dishes stored in the intermediate basket  52  and the upper basket  53 . 
     The first spray unit  41  may be arranged on the lower surface  12   b  of the tub  12 , unlike the second spray unit  42  and the third spray unit  43 . Particularly, the first spray unit  41  may be fixed to the sump  70 . 
     The dishwasher  1  may include a circulation pump  30  configured to pump water stored in the sump  70  toward the spray units  41 ,  42 , and  43 . The washing water pumped by the circulation pump  30  may be supplied to the first spray unit  41  through an alternating device  80  connected to the circulation pump  30 . Alternatively, the washing water pumped by the circulation pump  30  may be moved upward by a duct  90  and then supplied to the second spray unit  42  or the third spray unit  43 . 
     As mentioned above, the washing water stored in the sump  70  or washing water introduced into the dishwasher  1  from the outside may flow to the alternating device  80  by the circulation pump  30 . The alternating device  80  may supply the washing water to the first spray unit  41  through a connector (not shown) connected to the first spray unit  41 , and may supply the washing water to the duct  90  through a flow path  62  connected to the duct  90 . 
     The alternating device  80  may selectively supply the washing water to at least one of the connector and the duct  90 . The alternating device  80  may be arranged in a machine room L arranged below the washing chamber C. 
     The dishwasher  1  may include the machine room L arranged below the tub  12 . The machine room L may be formed by a lower frame  20 . 
     The above-described circulation pump  30 , sump  70 , and alternating device  80  may be arranged in the machine room L and further a water supply hose  131   a  and a drain hose  137   a  described later may be arranged in the machine room L (refer to  FIG.  7   ). 
     The dishwasher  1  may include the water supply hose  131   a  provided to supply washing water from the outside to the inside of the tub  12 , and the drain hose  137   a.    
     The dishwasher  1  may include the water supply hose  131   a  provided to supply washing water from the outside to the inside of the tub  12 . One end of the water supply hose  131   a  may be connected to the water tank assembly  100  communicating with the tub  12 . The other end of the water supply hose  131   a  may penetrate the lower frame  20  and be connected to an external water supply source (not shown). 
     The water tank assembly  100  is provided to be connected to a connection hole  12   e  formed on the side surface  12   d  of the tub  12 . 
     The water tank assembly  100  includes a water tank case  110 . The water tank case  110  may further include a tub fixer  123  configured to fix the water tank assembly  100  to the side surface  12   d  of the tub  12 . At least one fixer  123  may be formed. 
     The water tank case  110  may be formed in a shape and size corresponding to the side surface  12   d  of the tub  12 . In an embodiment of the disclosure, the water tank case  110  has a size and shape corresponding to the side surface  12   d  of the tub  12 , but is not limited thereto. For example, the water tank case may be smaller than the tub. 
       FIG.  3    is an exploded perspective view illustrating a water tank case in the dishwasher according to  FIG.  1   .  FIG.  4    is a plan view illustrating a second water tank case in the dishwasher shown in  FIG.  3   . 
     Referring to  FIGS.  3  and  4   , the water tank assembly  100  may be provided to supply washing water into the tub  12 . The water tank assembly  100  may be mounted on the tub  12 . The water tank assembly  100  may be mounted on the side surface  12   d  of the tub  12 . 
     The water tank assembly  100  may include the water tank case  110 . The water tank case  110  may include a first water tank case  111  and a second water tank case  112 . The water tank case  110  may be formed by coupling the first water tank case  111  and the second water tank case  112  to each other. 
     The first water tank case  111  is provided to be coupled to the tub  12 . The first water tank case  111  is provided to be in contact with and coupled to the side surface  12   d  of the tub  12 . An air hole  111   a  for discharging air to the outside or introducing air from the outside may be formed in at least a part of the first water tank case  111 . 
     A tub connection hole  113  communicating with the tub  12  may be formed in the first water tank case  111  for introducing air to the tub  12  or discharging air from the tub  12 . The tub communication hole  113  may be connected to the connection hole  12   e  formed on the side surface  12   d  of the tub  12 . 
     The first water tank case  111  and the second water tank case  112  may be coupled to each other to form the water tank case  110 . 
     The water tank case  110  may be provided with the tub fixer  123  configured to couple the water tank assembly  100  to the side surface  12   d  of the tub  12 . One or more tub fixer  123  may be provided. The tub fixer  123  may be provided on the first water tank case  111 . At least a part of the tub fixer  123  may be provided on the second water tank case  112 . The water tank case  110  may be fixed to the side surface  12   d  of the tub  12  through the tub fixer  123 . 
     The tub fixer  123  may include a first tub fixer  123   a,  a second tub fixer  123   b,  a third tub fixer  123   c,  and a fourth tub fixer  123   d  formed in the first water tank case  111 . The first tub fixer  123   a  to the fourth tub fixer  123   d  may be spaced apart from each other. In an embodiment of the disclosure, it is described that four tub fixers including the first tub  123   a  to the fourth tub  123   d  are spaced apart from each other in a water tank  300 , but the disclosure is not limited thereto. For example, the number of tub fixers may vary according to the size of the water tank case and the size and shape of the tub. 
     The tub fixer  123  may include a fifth tub fixer  123   a′  and a sixth tub fixer  123   d′  which are formed at a position, corresponding to the first tub fixer  123   a  and the fourth tub fixer  123   d,  in the second water tank case  112 . The fifth tub fixer  123   a′  and the sixth tub fixer  123   d′  may be formed to correspond to the first tub fixer  123   a  and the fourth tub fixer  123   d  so as to be coupled to the first tub fixer  123   a  and the fourth tub fixer  123   d,  respectively. 
     The water tank assembly  100  may include the air hole  111   a.  The air hole  111   a  may be formed in the water tank case  110 . The air hole  111   a  may be formed in the lower left side of the first water tank case  111 . Outside air may be introduced into the tub  12  or air inside the tub  12  may be discharged to the outside through the air hole  111   a.  In an embodiment of the disclosure, it is described that the air hole  111   a  is formed in the first water tank case  111  of the water tank assembly  100  but the disclosure is not limited thereto. 
     The water tank assembly  100  may further include a first flow path  210  provided inside the water tank case  110  to allow washing water to be introduced, and a first flow path wall  211  forming the first flow path  210 . The first flow path wall  211  may be provided in a pair. 
     The water tank assembly  100  may further include a second flow path  212  provided inside the water tank case  110  to allow washing water to be discharged, and a second flow path wall  213  forming the second flow path  212 . The second flow path wall  213  may be provided in a pair. 
     The water tank assembly  100  may include an air break  230  provided to prevent water from flowing backwards. The air break  230  may include an air break hole  231  formed by opening at least a portion of the second flow path  212 . 
     The water tank assembly  100  may further include an air break chamber  250  communicating with the air break  230  and provided to store water discharged from the air break  230 . 
     The water tank assembly  100  may include a third flow path  220  connecting the air break chamber  250  and the tub  12  so as to guide water of the air break chamber  250  to the tub  12 . 
     The water tank assembly  100  may include the water tank  300  provided in the water tank case  110  to store water passing through the first flow path  210 . 
     The water tank assembly  100  may include an inclined rib  270 . The inclined rib  270  may be formed to define the water tank  300  and the air break chamber  250  so as to allow a highest water level of the water tank to be higher than a height of the air break  230 . 
     The water tank assembly  100  may include a water supply pipe  131  formed at a lower end of the water tank case  110  to supply water from the outside, a regeneration water inlet valve  132  provided to discharge regeneration water stored inside the water tank case  110 , a water softener connector  133  provided to allow water, which is introduced into the water tank case  110 , to be moved to a water softening device, a sump drain connector  136  connected to the sump to allow washing water, which is after use, to be discharged to the outside by a drain pump (not shown), and a drain hose connector  137  provided to allow water, which is moved to the sump drain connector  136 , to be discharged to the outside. 
     The water tank assembly  100  may include a water tank inlet  134  formed at a lower end of the lower tank case  110  so as to allow water of the water softening device  160  to be introduced into the water tank  300 , and a sump connector  135  provided to discharge water stored in the water tank  300 . Water may be discharged to a sump connection hose  135   a  through the sump connector  135  (refer to  FIG.  7   ). 
     The water tank inlet  134  and the sump connector  135  may be located at the lower end of the water tank  300  of the water tank case  110 . 
     The water tank  300  of the water tank assembly  100  may be provided inside the water tank case  110 . The water tank  300  may be formed between the first water tank case  111  and the second water tank case  112 . The water tank  300  may be formed inside the first water tank case  111 . 
     The water tank  300  may include a plurality of ribs  301  guiding the flow of the water to allow the water to be smoothly moved through the water tank inlet  134  and the sump connector  135 . The rib  301  may include a first rib  301   a  arranged to be oblique, and a second rib  301   b  arranged in a direction perpendicular to the first rib  301   a.  A plurality of first ribs  301   a  and second ribs  301   b  may be spaced apart from each other. The plurality of ribs  301  may allow water to smoothly move inside the water tank  300 . 
     The water supply pipe  131  and the water softener connector  133  of the water tank assembly  100  may be provided to be connected to the first flow path  210 . The first flow path  210  of the water tank assembly  100  may be formed by using the first flow path wall  211  formed inside the water tank case  110 . The first flow path  210  may be formed in the first water tank case  111  and the second water tank case  112 , respectively. 
     The regeneration water inlet valve  132  of the water tank assembly  100  may be connected to the second flow path  212 . The second flow path  212  of the water tank assembly  100  may be formed by using the second flow path wall  213  formed inside the water tank case  110 . The second flow path  212  may be formed in the first water tank case  111  and the second water tank case  112 , respectively. 
     In an embodiment of the disclosure, it is described that each flow path wall is provided but the disclosure is not limited thereto. For example, the first flow path may be formed by the first flow path wall formed in the first water tank case and by the inner surface of the second water tank case. 
     At least a portion of the first and second flow paths  210  and  212  of the water tank assembly  100  may be curved inside the water tank case  110  to have a predetermined curvature. The first and second flow paths  210  and  212  may include at least one curved member to secure flow stability of the introduced water. 
     The water tank assembly  100  may be provided with a sensor  151  configured to detect an amount of washing water introduced into the water tank case  110 . The sensor  151  may be provided in the first flow path  210 . The sensor  151  may be installed in the first flow path  210  to detect the amount of washing water introduced through the water supply pipe  131 . The sensor  151  may be installed in a sensor installation member  215  formed in the water tank case  110 . The sensor installation member  215  may be formed on the first water tank case  111  and the second water tank case  112 , respectively. The sensor installation member  215  may be formed on a path of the first flow path  210 . 
     The air break chamber  250  of the water tank assembly  100  may be formed to communicate with the air break  230  of the first flow path  210 , and may store water discharged from the air break  230 . 
     The air break chamber  250  may include a guide  260  guiding water discharged from the air break  230 . The guide  260  may include a first guide rib  261  connected to the air break  230  and formed in a first inclination, and a second guide rib  262  spaced apart from the first guide rib  261  and formed in a second inclination so as to guide water to the third flow path  220 . The second guide rib  262  may be disposed below the first guide rib  261 . The second guide rib  262  may be located below the air break  230 . The second guide rib  262  may be located below the air break hole  231 . 
     The water tank case  110  may include a water flow wall  221  forming the third flow path  220  connecting the air break chamber  250  and the tub  12  so as to allow the water of the air break chamber  250  to be guided to the tub  12 . The water flow wall  221  may be formed on the first water tank case  111 . The water flow wall  221  may be formed by recessing at least a portion of the first water tank case  111  backward. The water flow wall  221  may be formed to be connected to at least a portion of the air break chamber  250 . The water flow wall  221  may be formed to connect between the air break chamber  250  and the tub  12 . 
     The water flow wall  221  may be provided to form at least a portion of the third flow path  220  provided to guide water, which is discharged through the air break hole  231  of the air break  230 , to the tub  12 . Another portion of the third flow path  220  may be formed by the first flow path wall  211  forming the first flow path  210  inside the water tank case  110 . The third flow path  220  may be formed between the air break chamber  250  and the tub communication hole  113 . 
     The water tank assembly  100  may further include a soft water chamber  310  and a regeneration water chamber  320 . The soft water chamber  310  and the regeneration water chamber  320  may be formed in the water tank  300 . 
     The soft water chamber  310  may be formed by the second flow path wall  213  and the water tank case  110  wall. The soft water chamber  310  may store water softened by a water softener  162  to be described later. That is, water may be supplied into the soft water chamber  310  through the water tank inlet  134 . 
     The soft water chamber  310  may be formed in a space from a space, in which water flows into the water tank inlet  134 , to the inclined rib  270 . That is, water may be stored in the soft water chamber  310  up to a free end  270   a  located at a lowest position of the inclined rib  270 . At this time, a state in which water is stored up to the free end  270   a  in the water tank  300  may be regarded as a full water level P. 
     The regeneration water chamber  320  may be formed between the first flow path wall  211  and the second flow path wall  213 . The regeneration water chamber  320  may supply regeneration water to a regenerator  161  to be described later. That is, water may be supplied to the regenerator  161  through the regeneration water inlet valve  132 . The regeneration water chamber  320  may extend up to the upper portion of the water tank  300 . 
       FIG.  5    is a view illustrating a part A in the dishwasher shown in  FIG.  4   .  FIG.  6    is a view illustrating a part B of the dishwasher shown in  FIG.  4   . 
     Referring to  FIGS.  5  and  6   , a pressure holder  340  may be provided at an upper portion of the regeneration water chamber  320  to store water without forming a water pocket in the regeneration water chamber  320 . The pressure holder  340  may be formed to be recessed on one surface of the second water tank case  112 . Therefore, because the pressure holder  340  is recessed, the soft water chamber  310  and the regeneration water chamber  320  may achieve atmospheric pressure equilibrium regardless of the second flow path wall  213 . 
     The pressure holder  340  may extend in the left and right direction to allow the regeneration water chamber  320  and the soft water chamber  310  to communicate with each other. The soft water chamber  310  may be connected to the outside through the open upper portion of the inclined rib  270 , the third flow path  220 , and the air hole  111   a.  Accordingly, the pressure holder  340  may allow the pressure in the regeneration water chamber  320  to be equilibrated with the pressure outside the water tank  300  (i.e., atmospheric pressure). 
     The pressure holder  340  may be formed at a higher position than the full water level P and thus the pressure holder  340  may not be submerged even when the water is stored in the water tank  300  at the full water level P. That is, the pressure holder  340  may be formed between the inclined rib  270  and the position of the full water level P. Accordingly, water may be stored at a high level in the water tank  300 . However, the position of the pressure holder  340  is not limited thereto, and may be formed in various positions as long as an air pocket is not formed in the regeneration water chamber  320  and water may be stored. 
     In addition, it is described that the shape of the pressure holder  340  is a rectangular shape with a long side in the left and right direction, but is not limited thereto. Alternatively, the pressure holder  340  may include various shapes. 
     A communication flow path  330  allowing the soft water chamber  310  to communicate with the regeneration water chamber  320  may be formed in the water tank  300 . Water introduced from the water tank inlet  134  may be stored in the soft water chamber  310 , and after the water reaches a predetermined level, the water may flow to the regeneration water chamber  320  through the communication flow path  330 . That is, the water may flow from the soft water chamber  310  to the communication flow path  330  and may flow from the communication flow path  330  into the regeneration water chamber  320 . Accordingly, the communication flow path  330  may be formed in a middle of the water tank  300  and thus after the soft water chamber  310  is filled with a predetermined soft water, the soft water may be moved to the regeneration water chamber  320 . Accordingly, water transferred from the soft water chamber  310  to the sump may be stored in a predetermined amount or more in the regeneration water chamber  320 . 
     The communication flow path  330  may be formed to be recessed on one surface of the water tank case  110 . Particularly, the communication flow path  330  may be recessed on one surface of the second water tank case  112 . Accordingly, water may flow from the soft water chamber  310  to the regeneration water chamber  320  through the recessed communication flow path  330  without interfering with the second flow path wall  213 . 
     The communication flow path  330  may bypass the second flow path wall  213  to extend vertically between the soft water chamber  310  and the regeneration water chamber  320 . That is, the communication flow path  330  and the second flow path  212  are not directly connected. Therefore, the water flowing through the communication flow path  330  may not be mixed with the water flowing through the second flow path  212 . Accordingly, water may be smoothly supplied to each of the soft water chamber  310  and the regeneration water chamber  320 . 
     The communication flow path  330  may extend vertically to allow water to flow from top to bottom. In the drawing, the communication flow path  330  is shown in a rectangular shape with a long side in the vertical direction, but is not limited thereto. Alternatively, the communication flow path  330  may be formed in various shapes. 
     A damper  331  may be provided in the communication flow path  330  to control an amount of water flowing from the soft water chamber  310  to the regeneration water chamber  320 . The damper  331  may adjust a flow rate and flow velocity to prevent the generation of the air pocket caused by a large amount of water rapidly flowing into the regeneration water chamber  320 . The damper  331  may open and close the communication flow path  330  by a controller (not shown) provided in the dishwasher  1 . 
       FIG.  7    is a view illustrating water supply and discharge in the dishwasher shown in  FIG.  1   . 
     Referring to  FIG.  7   , the dishwasher may further include the water softening device  160 . The water softening device  160  may include the water softener  162  to which an ionization resin filter is mounted and a regenerator  161  functioning to purify the ionization resin filter installed in the water softener  162  by using a substance such as salt. 
     The water softening device  160  may be arranged under the water tank  300 . That is, the water softener  162  and the regenerator  161  may be arranged under the water tank  300 . However, the position of the water softening device  160  is not limited thereto and may be arranged in various positions such as above the water tank  300 . 
     When water is supplied from the outside to the water supply pipe  131 , provided at the lower end of the water tank case  110 , through the water supply hose  131   a  for supplying the water into the water tank assembly  100 , the supplied water may flow along the first flow path  210 . The water flowing along the first flow path  210  may be moved to the second flow path  212  and the water flowing along the second flow path  212  may be moved to the water softener  162  from the water softener connector  133  through the water softener connection hose  133   a  formed at the lower end of the case  110 . Water, which is softened by the water softener  162 , may be connected to the water tank inlet  134  through the water tank connection hose  134   a.  Water introduced into the water tank  300  from the water tank inlet  134  may be stored in the soft water chamber  310 . When the water is stored and reaches the same water level as the communication flow path  330 , the water in the soft water chamber  310  may be moved to the regeneration water chamber  320  through the communication flow path  330 . Water stored in the regeneration water chamber  320  may be stored in the regeneration water chamber  320  based on the regeneration water inlet valve  132  not being opened. When a water level of the water stored in the regeneration water chamber  320  reaches the water level at the same position as the communication flow path  330 , the water level of the soft water chamber  310  and the water level of the regeneration water chamber  320  may rise to the same height. When water is continuously supplied from the water softener  162 , the water may be stored up to the full water level P. 
     The water constantly supplied to the soft water chamber  310  may also be stored in the regeneration water chamber  320  and thus the regeneration water chamber  320  may stably store regeneration water to be supplied to the regenerator  161 . That is, water for regeneration may be sufficiently stored in the regeneration water chamber  320 . Accordingly, water for regeneration may be sufficiently supplied into the regenerator  161 , and a reduction in performance of the water softener  162  may be prevented. In addition, it is possible to reduce difficulty in supplying regeneration water caused by the installation environment of the dishwasher  1 . 
     In response to opening the regeneration water inlet valve  132 , regeneration water may be supplied to the regenerator  131  through the regeneration water input hose  132   a.  Accordingly, the regenerator  161  may regenerate the water softener  162 . 
     The regeneration water inlet valve  132  may be provided at the lower portion of the regeneration water chamber  320  and control whether to supply water to be supplied to the regenerator  161 . In order to prevent the water stored in the soft water chamber  310  from being discharged into the regeneration water chamber  320 , the regeneration water inlet valve  132  may be opened in response to the water level in the soft water chamber  310  being lower than the water level in the regeneration water chamber  320 . For example, the regeneration water inlet valve  132  may be opened when the soft water chamber  310  is empty. However, it is not limited to the above examples. 
     Alternatively, when the dishwasher  1  is in a drying cycle, the regeneration water inlet valve  132  may be opened. That is, the regeneration water inlet valve  132  may be opened during a final cycle of the dishwasher  1 . However, it is not limited to special cycle. Alternatively, in response to closing the door  11 , the regeneration water inlet valve  132  may be opened. 
     The regeneration water inlet valve  132  may be opened in the above-mentioned states. Accordingly, the water stored in the water tank  300  may be prevented from leaking even when a user opens the door  11  or stops the dishwasher  1  during operation. At this time, it is possible to detect whether the door is open or not through a sensor (not shown) provided on the door  11 . 
     While the present disclosure has been particularly described with reference to exemplary embodiments, it should be understood by those of skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the present disclosure.