Patent Publication Number: US-2023144208-A1

Title: Dishwasher

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application PCT/KR2021/007811, filed Jun. 22, 2021, and claims foreign priority to Korean application 10-2020-0090728, filed Jul. 22 2020, the disclosures of which are incorporated herein by reference in their entireties. 
    
    
     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 high pressure into a washing tub 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 tub 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 a bottom of the tub. 
     The dishwasher is provided with a water tank that delivers the supplied washing water to the sump. The water tank may previously store water used for washing and set cold water of a water supply to a temperature corresponding to the room temperature. Accordingly, it is possible to reduce energy used to heat the washing water. 
     However, when the dishwasher is laid down during the after-sales service, the washing water stored in the water tank may flow out into an outside air inlet formed in the water tank to maintain an internal pressure. 
     In general, a flow meter configured to detect a flow rate of water supplied to the water tank and a printed circuit board (PCB) coupled to the flow meter are accommodated in the water tank such that the flow meter, the PCB and the water tank are fused integrally with each other so as not to be separated from each other. Accordingly, if a defect occurs in the PCB, the entire water tank may need to be replaced. 
     SUMMARY 
     One aspect of the present disclosure provides a dishwasher including a tub forming a washing chamber, a water tank mounted on an outer circumferential surface of the tub and including a reservoir in which washing water is storable, and an inclined rib configured to, with washing water stored in the reservoir, have an inclination with respect to a water surface of the washing water to allow an air pocket to be formed under the inclined rib. The dishwasher may further include a sump configured to receive washing water stored in the reservoir and to supply the received washing water to the tub. 
     The water tank may further include a partition wall forming a side of the reservoir. The inclined rib may include an extension connected to the partition wall, and a free end at one end of the extension to allow washing water in the reservoir to flow to an upper portion of the inclined rib. 
     The inclined rib may be inclined to allow the extension to be positioned higher than the free end. 
     The partition wall, the extension, and the water surface of the washing water may form a closed space, thereby forming the air pocket. 
     The water tank may further include a first flow path along which washing water is suppliable to the water tank from an outside. The partition wall may form a portion of a flow path wall forming the first flow path. 
     The water tank may further include a tub connection port formed to communicate with the tub, an outside air inlet, and a second flow path connecting the reservoir, the tub connection port, and the outside air inlet to allow air to flow. 
     The inclined rib may be provided to trap a portion of the washing water stored in the reservoir in response to the water tank being rotated. 
     The water tank may further include a water overflow prevention rib extending along a periphery of the tub connection port so as to interfere with a flow of washing water, which overflows from the reservoir, along the second flow path due to the rotation of the water tank. 
     The water tank may further include a water collecting rib formed between the tub connection port and the outside air inlet so as to collect the washing water in response to the rotation of the water tank. 
     The water collecting rib may include a first wall extending from the tub connection port to a lateral side of the water tank, a second wall connected to the first wall and extending upward, and a third wall connected to the second wall and extending to an upper side of the tub connection port. 
     The water tank may further include a plurality of leakage prevention ribs formed between the water collecting rib and the outside air inlet so as to prevent water, which is not collected by the water collecting rib, from leaking to the outside air inlet in response to the rotation of the water tank. 
     The water tank may further include a flow meter configured to detect a flow rate of washing water supplied to the water tank, a first case in which the flow meter is accommodated, and a second case corresponding to the first case and provided to cover a portion of the flow meter. 
     The second case may include a folding flange provided to be foldable and including a hook formed on one end of the folding flange. The hook may be coupled to the cover to allow the folding flange to cover the flow meter. 
     The flow meter may include a body including an impeller, and a printed circuit board (PCB) detachably mounted to the body so as to be connected to a wire. The second case may include a wire hanger formed to be cut so as to guide the wire. 
     The second case may further include a guard protruding from an outer surface of the second case to prevent moisture from penetrating into the PCB. 
     Another aspect of the present disclosure provides a dishwasher including a tub forming a washing chamber, and a water tank mounted on an outer circumferential surface of the tub so as to receive washing water from an external water source. The water tank includes a flow meter including a sensor configured to detect a flow rate of supplied washing water, a first case in which the flow meter is accommodated, and a second case coupled to the first case and including a folding flange provided to cover the flow meter. 
     The second case may include a cover provided to cover a portion of the flow meter. The folding flange may be formed integrally with the second case so as to be foldable, and a hook coupled to the cover may be formed on one end of the folding flange. 
     The flow meter may include a body including an impeller, and a printed circuit board (PCB) detachably mounted to the body so as to be connected to a wire. The second case may include a wire hanger formed to be cut so as to guide the wire. 
     Another aspect of the present disclosure provides a dishwasher including a tub forming a washing chamber and a water tank mounted on an outer circumferential surface of the tub to communicate with the tub. The water tank includes a reservoir provided to store washing water and including a washing water outlet, a partition wall forming one side surface of the reservoir, an outside air inlet provided to maintain an internal pressure, a flow path connecting the reservoir to the outside air inlet, and an inclined rib having an inclination with respect to a water surface of the washing water in the reservoir and provided to form an air pocket. The inclined rib includes an extension connected to the partition wall, and a free end provided at one end of the extension to form the washing water outlet. 
     The free end may be positioned to be lower than the extension. 
     Additional aspects 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 presented embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features, and advantages of certain embodiments of the present disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which: 
         FIG.  1    is a perspective view of a dishwasher according to one embodiment of the present disclosure. 
         FIG.  2    is a schematic side cross-sectional view of the dishwasher according to one embodiment of the present disclosure. 
         FIG.  3    is a view illustrating a state in which a water tank of the dishwasher according to an embodiment of the present disclosure is mounted on a tub. 
         FIG.  4    is an exploded view illustrating a configuration of the water tank of the dishwasher according to an embodiment of the present disclosure. 
         FIG.  5    is a view illustrating a state in which the water tank of the dishwasher according to an embodiment of the present disclosure is rotated. 
         FIG.  6    is an enlarged view of a part A of  FIG.  4   . 
         FIG.  7    is a view illustrating a portion of a flow path of the dishwasher according to one embodiment of the present disclosure. 
         FIG.  8    is an enlarged view of a part C of  FIG.  5   . 
         FIG.  9    is an enlarged view of a part B of  FIG.  4   . 
         FIG.  10    is an enlarged view illustrating a state in which a flow meter is mounted on a part D of  FIG.  4   . 
         FIG.  11    is an exploded view of the flow meter of  FIG.  10   . 
         FIG.  12    is a view illustrating a state in which a folding flange is not folded in the water tank of the dishwasher according to one embodiment of the present disclosure. 
         FIG.  13    is a view illustrating a state in which the folding flange of  FIG.  12    is folded. 
         FIG.  14    is a cross-sectional view taken along line A-A″ of  FIG.  13   , illustrating a state in which the folding flange is not folded. 
         FIG.  15    is a view illustrating a state in which the folding flange of  FIG.  14    is folded. 
     
    
    
     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. Shapes and sizes of elements in the drawings may be exaggerated for clear description. 
     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. 
     According to various embodiments of the present disclosure, a dishwasher includes an improved structure to prevent washing water from leaking to an outside even when a water tank is rotated during an after-sales service. 
     According to various embodiments of the present disclosure, a dishwasher includes an improved structure to allow only a printed circuit board (PCB) sensor inside a water tank to be replaced. 
     According to various embodiments of the present disclosure, an inclined rib is provided to form an air pocket, and thus when a water tank is tilted, it is possible to minimize an amount of washing water overflowing out of a reservoir by using an air pressure. 
     According to various embodiments of the present disclosure, even when washing water overflows out of a reservoir, it is possible to prevent the washing water from leaking to an outside through an outside air inlet. 
     According to various embodiments of the present disclosure, it is possible to separate and replace only a printed circuit board (PCB) from an outside of a dishwasher because a folding flange is provided. Accordingly, it is possible to reduce production and repair costs. 
     The disclosure will be described more fully hereinafter with reference to the accompanying drawings. 
       FIG.  1    is a perspective view of a dishwasher according to one embodiment of the present disclosure.  FIG.  2    is a schematic side cross-sectional view of the dishwasher according to one embodiment of the present disclosure. 
     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, in the plurality of baskets  51 ,  52 , and  53 , not only large-volume dishes but also relatively small-volume dishes may be accommodated. 
     The storage container 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 . Particularly, the intermediate guide rack  13   a  and the lower guide rack  13   b  may be installed on an inner surface of the side surface  12   d  of the tub  12 . 
     The storage container 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. 
     In addition, the shape of the storage container is not limited to the shape shown in  FIGS.  1  to  3   . For example, the upper basket  53  may be removed according to the size of the tub  12 . Therefore, the storage container may be implemented only with the intermediate basket  52  and the lower basket  51 . 
     The dishwasher  1  may 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 may be defined as an inner space of the tub  12 . The sump  70  may be configured to supply washing water to the tub  12 . 
     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 a 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. The switching assembly may be installed on a rail by a holder, and translated along the rail. 
     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 arranged to 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 unit. 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  81  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  81  and the duct  90 . 
     The dishwasher  1  may include a machine room L arranged below the tub  12 . At least a portion of the connector  81 , and the flow path  62  may be arranged in the machine room L arranged below the washing chamber C. That is, at least a portion of the connector  81  and the flow path  62  may be arranged lower than the lower surface  12   b  of the tub  12  with respect to the height direction of the dishwasher  1 . 
     Through the connector  81  and the flow path  62 , the washing water may flow to the first spray unit  41  and the duct  90  arranged inside the washing chamber C. The washing water may flow to the second spray unit  42  and the third spray unit  43  through the duct  90 . 
     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 (not shown) and a drain hose (not shown) may be arranged in the machine room L. 
     The tub  12  may include a connection hole  12   e  formed in the side surface  12   d . The connection hole  12   e  may be provided to communicate with a tub connection port  240  of a water tank  100  to be described later. 
       FIG.  3    is a view illustrating a state in which a water tank of the dishwasher according to an embodiment of the present disclosure is mounted on the tub  12 .  FIG.  4    is an exploded view illustrating a configuration of the water tank of the dishwasher according to an embodiment of the present disclosure.  FIG.  5    is a view illustrating a state in which the water tank of the dishwasher according to an embodiment of the present disclosure is rotated.  FIG.  6    is an enlarged view of a part A of  FIG.  4   .  FIG.  7    is a view illustrating a portion of a flow path of the dishwasher according to one embodiment of the present disclosure.  FIG.  8    is an enlarged view of a part C of  FIG.  5   .  FIG.  9    is an enlarged view of a part B of  FIG.  4   . 
     As illustrated in  FIG.  3   , the dishwasher  1  may include the water tank  100 . The water tank  100  may be mounted on an outer circumferential surface of the tub  12 . Particularly, the water tank  100  may be mounted on the side surface  12   d  of the tub  12 . The water tank  100  may be connected to the sump  70  to supply washing water to the sump  70 . However, a specific connection related thereto is not shown in  FIG.  3   . 
     The water tank  100  may typically include a flow meter  110  configured to detect an amount of washing water supplied to the inside of the dishwasher  1 . In addition, a folding flange  320  configured to be folded may be formed on the outer circumferential surface of the water tank  100 . Details related to this will be described later. 
     In recent years, more functions have been added to the water tank  100  due to an energy saving issue. The water tank  100  may previously store the washing water used for washing, so as to allow cold water of a water supply to be a temperature at the same as the room temperature. 
     The washing water may be stored in a reservoir  210  of the water tank  100  for a predetermined period of time, and accordingly, a temperature of the washing water (about 15° C.) is similar to the room temperature (about 23° C.). Therefore, it is possible to reduce an amount of energy that is used to increase the temperature of the washing water. 
     Accordingly, it is possible to reduce the energy required to heat the washing water used for washing. 
     Referring to  FIG.  4   , the water tank  100  may include a plurality of cases  200  and  300 . The water tank  100  may include a first case  200  and a second case  300 . The first case  200  and the second case  300  may be coupled to each other. Particularly, the first case  200  and the second case  300  may be fused to each other. 
     The first case  200  and the second case  300  may be coupled to each other to form the water tank  100 . The first case  200  may be provided to correspond to the second case  300  to form a plurality of flow paths  231 ,  232 ,  233 , and  234  and the reservoir  210  in the water tank  100 . 
     Accordingly, unless otherwise described, structures of an inner surface of the first case  200  and the second case  300  facing each other may be formed to be mostly the same. Hereinafter the first case  200  will be described, but the second case  300  may also include the same structure and be given the same reference numerals. 
     The first case  200  is provided to be coupled to the tub  12 . The first case  200  is provided to be coupled to the side surface  12   d  of the tub  12 . The second case  300  may be coupled to the first case  200  to be arranged outside the tub  12  more than the first case  200 . 
     The first case  200  may include an outside air inlet  250  provided to discharge air to the outside or introduce air from the outside. Alternatively, the outside air inlet  250  may be formed in the second case  300 . 
     The first case  200  may include the tub connection port  240  provided to introduce air into the tub  12  or provided to discharge air from the tub  12 . The tub connection port  240  may be connected to the connection hole  12   e  formed in the side surface  12   d  of the tub  12 . 
     The water tank  100  may include a cap member  180  connecting the water tank  100  and the side surface  12   d  of the tub  12  without the leakage. The cap member  180  may be mounted on the tub connection port  240  of the water tank  100  and the connection hole  12   e  of the tub  12  to maintain the sealing. 
     A tub fixer  120  configured to couple the water tank  100  to the side surface  12   d  of the tub  12  may be provided in the first case  200 . One or more tub fixer  120  may be provided. The water tank  100  may be fixed to the side surface  12   d  of the tub  12  through the tub fixer  120 . 
     The tub fixer  120  may include a first tub fixer  121 , a second tub fixer  122 , a third tub fixer  123 , and a fourth tub fixer  124 . 
     The first tub fixer  121  to the fourth tub fixer  124  may be arranged to be spaced apart from each other. In the embodiment of the present disclosure, the four tub fixers including the first tub fixer  121  to the fourth tub fixer  124  are illustrated as being spaced apart from each other in the water tank  100 , but the present disclosure is limited thereto. For example, the number of tub fixers  120  may vary according to the size of the first case  200  and the size and shape of the tub  12 . 
     The water tank  100  may include a coupling member  190 . The coupling member  190  may be inserted into the first tub fixer  120  formed in the first case  200  and the second case  300  of the water tank  100  so as to assist the coupling between the tub  12  and the water tank  100 . 
     The water tank  100  may include the reservoir  210 . Washing water that is softened may be introduced into the reservoir  210  through a water supplier  131  to be described later. As the washing water introduced into the reservoir  210  is stored inside the reservoir  210  and maintained at the room temperature, it is possible to reduce energy required for heating the washing water. 
     The water tank  100  may include the water supplier  131  formed on a lower end  281   b  of the first case  200  and configured to receive water from the outside. The water tank  100  may include a water softener connector  133  provided to allow water introduced from the water supplier  131  to be moved to a water softener (not shown). 
     In addition, the water tank  100  may include a soft water inlet  134  formed at the lower end  281   b  and provided to allow water, which is softened, to be introduced from the water softer (not shown) to the reservoir  210 , and a sump connector  135  provided to allow washing water stored in the reservoir  210  to be discharged to the sump  70 . 
     The water tank  100  may include a sump drain connector  136  connected to the sump  70  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 introduced into the sump drain connector  136 , to be discharged to the outside. 
     In addition, the water tank  100  may include a regeneration water inlet  132  through which washing water flows from the reservoir  210  for ion exchange of the water softer (not shown) that is separately provided. 
     The water tank  100  may include the flow meter  110 . The flow meter  110  may be configured to detect the flow rate of the washing water supplied from the water supplier  131 . A detailed configuration of the flow meter  110  will be described later. 
     The water tank  100  may include a plurality of ribs  150 . Particularly, the plurality of ribs  150  may be formed in the reservoir  210  of the water tank  100 . The plurality of ribs  150  may guide the flow of washing water introduced from the water supplier  131  to the reservoir  210 . Particularly, the plurality of ribs  150  may be provided to allow the washing water to be uniformly moved in various directions and supplied to the reservoir  210 . 
     Accordingly, a pressure applied to the water tank  100  by the washing water may be uniformly formed, thereby preventing the bulging of the water tank  100 . 
     As shown in  FIG.  5   , the water tank  100  may be laid down when the after-sales service is performed. Particularly, the water tank  100  may be rotated such that a position of the outside air inlet  250  provided at the lower left is located at the lower right. That is, the water tank  100  may be rotated counterclockwise, and at this time, a washing water flow hole  212  to be described later may be located above the outside air inlet  250 . 
     Referring to  FIGS.  4  and  5   , the water tank  100  may include a plurality of flow paths  62 . Particularly, the water tank  100  may include a first flow path  231 , a second flow path  232 , a third flow path  233 , and a fourth flow path  237 . 
     Hereinafter an original state in which the water tank  100  is erected is referred to as a first state, and a state in which the water tank  100  is rotated and laid down as shown in  FIG.  5    for the after-sales service is referred to as a second state. 
     The water tank  100  may include the first flow path  231  provided to allow washing water to be supplied from the outside and to flow in the first state. The first flow path  231  is provided to allow washing water to be introduced from the water supplier  131  and to be discharged to the water softener connector  133 . A flow path wall  236  may be provided to form the first flow path  231 . 
     The flow meter  110  may be installed in the first flow path  231  so as to detect the amount of washing water introduced from the water supplier  131 . 
     At least a portion of the first flow path  231  of the water tank  100  may be bent inside the water tank  100  to have a predetermined curvature. The first flow path  231  includes at least one bent member in order to secure a flow stability of the introduced water. 
     An air break hole  160  may be formed on the first flow path  231  of the water tank  100 . Particularly, the air break hole  160  may be formed in the flow path wall  236  forming the first flow path  231 . Details related thereto will be described later. 
     Washing water discharged to the water softener connector  133  is introduced into the reservoir  210  through the soft water inlet  134  after passing through a softening process in the water softer. The water softener (not shown) may include a water softening tank (not shown) equipped with an ionization resin filter, and a regeneration tank (not shown) containing substances such as salt to purify the ionization resin filter mounted on the water softening tank. Washing water that is softened by the water softer and introduced into the water tank  100  may be stored in the reservoir  210 . 
     The water tank  100  may include the plurality of ribs  150  provided to guide the movement of the washing water so as to allow the washing water to be smoothly moved through the soft water inlet  134  and the sump connector  135  in the first state of the water tank  100 . The plurality of ribs  150  may be formed in the reservoir  210 . Each of the ribs may include a first rib  151  disposed diagonally and a second rib  152  disposed in a direction substantially perpendicular to the first rib  151 . A plurality of first ribs  151  and second ribs  152  may be disposed to be spaced apart from each other. The plurality of ribs  150  may be provided to guide the water to be smoothly moved in the reservoir  210  inside the water tank  100 . 
     In the first state, the reservoir  210  may be filled with the introduced washing water until the washing water comes into contact with an inclined rib  220 . At this time, the inclined rib  220  may be formed to allow an air pocket (P) to be formed under the inclined rib  220 . The inclined rib  220  may be provided to have an inclination with respect to a water surface of the washing water. Details related to the inclined rib  220  will be described later. 
     The water tank  100  may include the second flow path  232 . The second flow path  232  may be provided to allow washing water overflowing from the reservoir  210  to be moved. The washing water flow hole  212  may be provided at one side of the inclined rib  220  to allow washing water to be moved from the reservoir  210  to an upper portion of the inclined rib  220 . The washing water may be introduced into the tub  12  through the tub connection port  240  from the reservoir  210  along the second flow path  232 . 
     Further, the second flow path  232  may be provided to allow air to be moved. The second flow path  232  may be provided to connect the reservoir  210 , the tub connection port  240 , and the outside air inlet  250 . Accordingly, an internal pressure of the tub  12  and an internal pressure of the water tank  100  may be maintained at atmospheric pressure. Therefore, because a closed space is not filled with the washing water, washing water may be easily supplied into the water tank  100  without resistance. 
     The water tank  100  may include the third flow path  233 . The third flow path  233  is provided to regenerate the water softer (not shown) by using washing water stored in the reservoir  210 . The third flow path  233  may be provided to connect the reservoir  210  to the regeneration water inlet  132 . The washing water stored in the reservoir  210  is moved to the third flow path  233  through a second water flow wall  235 . 
     The water tank  100  may include the fourth flow path  237 . The fourth flow path  237  may be provided as a drain flow path  62 . The fourth flow path  237  may be provided to connect the sump drain connector  136  to the drain hose connector  137 . The fourth flow path  237  may be provided to allow the washing water, which is after use, to be discharged to the outside by the drain pump (not shown). 
     In the embodiment, the outside air inlet  250  may be provided to be located at the lower left side of the water tank  100 , and the washing water flow hole  212  may be located at the upper right side of the water tank  100  based on the first state. However, the position of the outside air inlet  250  may vary according to the position of the washing water flow hole  212 . For example, when the washing water flow hole  212  is provided to be located at the upper left side of the water tank  100 , the outside air inlet  250  may be located at the lower right side of the water tank  100 . 
     In the second state of the water tank  100 , the washing water stored in the reservoir  210  may flow into the second flow path  232  through the washing water flow hole  212 . As the washing water flow hole  212  and the outside air inlet  250  are arranged in a substantially diagonal direction in the water tank  100 , a flow path of the washing water overflowing through the washing water flow hole  212  may be increased. Accordingly, a plurality of structures may be formed on the second flow path  232  to prevent the washing water from leaking into the outside air inlet  250 . 
     Referring to  FIGS.  4  to  6   , the water tank  100  may include the inclined rib  220 . The inclined rib  220  may be formed above the reservoir  210 . 
     The water tank  100  may include a partition wall  211 . The partition wall  211  may be provided to form the side surface  12   d  of the reservoir  210 . The partition wall  211  may be provided to form a portion of the flow path wall  236  forming the first flow path  231 . Particularly, the partition wall  211  may be provided to form a left side surface of the reservoir  210 . 
     The inclined rib  220  may include an extension  221  and a free end  222 . The inclined rib  220  may be provided to be connected to the partition wall  211 . The extension  221  is a portion, connected to the partition wall  211 , in the inclined rib  220 . The free end  222  may be formed at one end of the extension  221 . The washing water flow hole  212  may be formed on a lateral side of the free end  222 . The washing water stored in the reservoir  210  may be moved to the upper portion of the inclined rib  220  through the washing water flow hole  212 . 
     The washing water introduced into the reservoir  210  may rise until the washing water comes into contact with an inclined rib  220 . A water level, when the water surface of the washing water is in contact with the inclined rib  220 , is referred to as a full water level of reservoir F. 
     The inclined rib  220  may be provided to have an inclination with respect to the water surface of the washing water. Particularly, the inclined rib  220  may have an inclination to allow the extension  221  to be positioned higher than the free end  222 . In this case, when the washing water rises and reaches the full water level of reservoir F, the extension  221  and the partition wall  211  of the inclined rib  220 , and the water surface of the washing water may form a closed space. The air pocket P may be formed in the closed space. 
     Therefore, by the air pocket P, washing water under the inclined rib  220  may not rise above the full water level of reservoir F. 
     Washing water, which is additionally supplied after reaching the full water level of reservoir F, may be moved to the upper portion of the inclined rib  220  through the washing water flow hole  212 . The washing water flow hole  212  may form the second flow path  232  so as to connect the reservoir  210  and the tub connection port  240 . 
     An inclination angle θ of the inclined rib  220  may be provided to be 10 degrees or less. When the inclined rib  220  has a relatively large inclination angle θ, an area of the air pocket P formed among the partition wall  211 , the inclined rib  220  and the water surface may be slightly large and it is difficult to secure a predetermined amount of washing water, stored in the reservoir  210 , or more. That is, according to the embodiment, the inclination angle θ of the inclined rib  220  may be provided to be 10 degrees or less in order to secure the predetermined amount of the washing water, or more. 
     When the water tank  100  is rotated from the first state to the second state, the above-described air pocket P formed under the inclined rib  220  may prevent washing water stored in the reservoir  210  from passing through the washing water flow hole  212  to a certain extent. In other words, even when the water tank  100  is tilted at the full water level, the outflow of the washing water from the reservoir  210  may be interfered with the pressure of the air pocket P, thereby minimizing the overflow of the washing water. Accordingly, it is possible to reduce a risk of leaking the washing water to the outside air inlet  250  along the second flow path. 
     Referring to  FIGS.  4 ,  5 , and  7   , the air break hole  160  of the water tank  100  may be formed on the first flow path  231 . The air break hole  160  may be formed in the flow path wall  236  forming the first flow path  231 . Particularly, the air break hole  160  may be formed in a bent member positioned at an upper portion of the bent member of the flow path wall  236 . 
     The water tank  100  may include a flow rate increasing member  170 . The flow rate increasing member  170  is installed in the first flow path  231  to increase the flow rate. The flow rate increasing member  170  may be coupled to the flow path wall  236  so as to reduce a cross-sectional area of the first flow path  231 , thereby increasing the flow rate. 
     The water tank  100  may include a plurality of guide  161  and  162 . The plurality of guides  161  and  162  may be provided to guide the washing water flowing out through the air brake hole  160 . 
     The plurality of guides  161  and  162  may include a first guide  161  and a second guide  162 . The first guide  161  is formed on the flow path wall  236  forming the first flow path  231  and has a first inclination. The first inclination may be provided at an angle substantially perpendicular to the ground. The second guide  162  may be formed to be spaced apart from the first guide  161 , and have a second inclination to guide water to the second flow path  232 . The second guide  162  may be disposed below the first guide  161 . The second guide  162  may be located under the air brake hole  160 . 
     In addition, the water tank  100  may include a first water flow wall  234  forming the second flow path  232  to guide water, which overflows from the reservoir  210 , to the tub  12 . In accordance with a position of the first water flow wall  234 , a portion of the flow path wall  236  forming the first flow path  231  may be cut to form the second flow path  232 . The flow path wall  236  may include a flow groove  236   a  that is cut by a height of the first water flow wall  234 . 
     The first water flow wall  234  may be formed by recessing at least a portion of the first case  200  to a rear side. The rear side is a direction toward the tub  12  from the first case  200 . 
     Washing water may flow on the second flow path  232  through the first water flow wall  234  and the flow groove  236   a . Particularly, washing water overflowing from the reservoir  210  may flow to the upper portion of the inclined rib through the washing water flow hole  212  as described above, and may be moved to the lateral side of the water tank  100  through the first water flow wall  234  and the flow groove  236   a . The washing water flowing to the lateral side may be discharged from the water tank  100  to the tub connection port  240  by gravity. 
     Hereinafter a structure for preventing the leakage of the washing water when the water tank  100  is rotated to the second state for the after-sales service of the dishwasher  1  will be described. 
     Referring to  FIGS.  5  and  8   , the water tank  100  may be rotated for the after-sales service. As shown in  FIG.  5   , the state in which the washing water flow hole  212  is located at the upper portion and the outside air inlet  250  is located at the lower portion may be referred to as the second state. For the after-sales service of the dishwasher  1 , the water tank  100  may be rotated in various directions. However, when the water tank  100  is rotated in a direction, in which the door  11  of the dishwasher  1  is located on the floor, opposite to that shown in  FIG.  5   , the outside air inlet  250  is located at the upper portion of the water tank  100  and thus the leakage of the washing water may not occur. Therefore, the second state in which the water tank  100  is laid down such that the outside air inlet  250  is located at the lower right side of the water tank  100  as shown in  FIG.  5   , for the after-sales service will be described. 
     When the water tank  100  is rotated to the second state, the leakage of the washing water stored in the reservoir  210 , to the outside air inlet  250  may be primarily prevented by the inclined rib  220 . 
     Particularly, because the inclined rib  220  is provided to form the side surface  12   d  of the reservoir  210 , the inclined rib  220  may serve to confine a portion of the washing water stored in the reservoir  210  during rotation of the water tank. 
     In addition, when the water tank  100  is rotated, the air pocket P shown in  FIG.  6    may be moved along the water surface of the washing water, thereby preventing the washing water from leaking into the washing water flow hole  212  to a certain extent. By the pressure of the air pocket P, it is possible to prevent the primary outflow of the washing water flowing through the second flow path  232 . 
     However, due to the washing water flow hole  212 , it is impossible to completely prevent the washing water from leaking into the second flow path  232 . Accordingly, various structures may be formed to prevent the washing water, which flows along the second flow path  232 , from leaking into the outside air inlet  250 . 
     The water tank  100  may include a water overflow prevention rib  260 . The water overflow prevention rib  260  may be formed at the end  281   b  of the second flow path  232 . The water overflow prevention rib  260  may guide the washing water to the tub connection port  240  in the first state of the water tank  100 . However, in the second state of the water tank  100 , the water overflow prevention rib  260  may interfere with the flow of the washing water along the second flow path  232  so as to prevent the washing water from overflowing to a side adjacent to the outside air inlet  250 . The water overflow prevention rib  260  may extend along a periphery of the tub connection port  240 . Particularly, the water overflow prevention rib  260  may extend in a direction, which is opposite to gravity based on the second state of the water tank  100 , to interfere with the flow of washing water. 
     The water tank  100  may include a water collecting rib  270 . The water collecting rib  270  may be formed between the tub connection port  240  and the outside air inlet  250 . The water collecting rib  270  may be provided to collect the washing water overflowing from the water overflow prevention rib  260  in the second state of the water tank  100 . 
     The water collecting rib  270  may include a first wall  271 , a second wall  272 , and a third wall  273 . The first wall  271  may extend from the tub connection port  240  to the lateral side of the water tank  100 . The second wall  272  may be connected to the first wall  271  and extend upward based on the first state of the water tank  100 . The third wall  273  may be connected to the second wall  272  to extend upwards of the tub connection port  240  based on the first state of the water tank  100 . Accordingly, a water collecting space may be formed between the first wall  271 , the second wall  272 , and the third wall  273 , so as to collect the washing water. 
     The water tank  100  may include a plurality of leakage prevention ribs  281 ,  282 , and  283 . The plurality of leakage prevention ribs  281 ,  282 , and  283  may be provided between the water collecting rib  270  and the outside air inlet  250 . The plurality of leakage prevention ribs  281 ,  282 , and  283  may prevent water, which is not collected by the water collecting rib  270  and overflows from the water collecting rib  270 , from leaking to the outside air inlet  250  when the water tank  100  is rotated. 
     Each of the leak prevention ribs  281 ,  282 ,  283  may include a connector  281   a  and an end  281   b . The connector  281   a  may be connected to an inner wall  201  of the water tank  100  or spaced apart from the inner wall  201  of the water tank  100 . The end  281   b  may be formed at one end of the connector  281   a  to allow air to pass therethrough. 
     The adjacent leakage prevention ribs  281 ,  282 , and  283  may allow the flow path  62 , through which the air flows, to be a zigzag pattern and thus it is difficult for the washing water to pass through the flow path  62  while the air easily passes through the flow path  62 . Particularly, each of the leak prevention ribs  281 ,  282 , and  283  may be inclined to allow the end  281   b  to be higher than the connector  281   b  based on the first state of the water tank  100 . 
     Referring to  FIGS.  4  and  9   , the water tank  100  may include the second water flow wall  235 . The second water flow wall  235  may be formed by being recessed to the rear of the water tank  100 . The second water flow wall  235  may be provided to allow the washing water stored in the reservoir  210  to flow into the third flow path  233 . 
     The water softener (not shown) is configured to adsorb and remove heavy metals and metallic ions contained in the washing water flowing into the water supplier  131 . The water softener (not shown) changes washing water into soft water with excellent cleaning power. However, as an ion exchange resin adsorbs the metallic ions contained in the washing water, a volume of the ion exchange resin inside the water softener (not shown) is increased, and thus a capacity of the ion exchange resin for adsorbing the metallic ions may be reduced. 
     Therefore, by supplying water to the regeneration water inlet  132  for the ion exchange, it is possible to regenerate the ion exchange resin of the water softener (not shown) to restore the water softening ability. Regeneration of the ion exchange resin is a process of removing metallic ions contained in the ion exchange resin. Accordingly, the ions in the ion exchange resin, which are depleted as the softening reaction continues, may be reduced by the ion exchange reaction. 
     Therefore, through the second water flow wall  235 , it is possible to store and supply the washing water required for regeneration of the water softener (not shown). 
     As in the above-described embodiment of the present disclosure, the inner surfaces of the first case  200  and the second case  300  are not limited to being provided to partition the above-described respective structures. For example, the above-described structure may be provided only on the inner surface of the first case  200 , and the inner surface of the second case  300  may be provided with a flat surface to cover the first case  200 , thereby providing a closed space inside the water tank  100 . Alternatively, the above-described structure may be provided only on the inner surface of the second case  300 , and the inner surface of the first case  200  may be provided with a flat surface to cover the second case  300 , thereby providing a closed space inside the water tank  100 . 
     Even when the water tank  100  is rotated as the dishwasher  1  is rotated upon performing the after-sales service, the washing water stored in the water tank  100  may not leak to the outside by the above-mentioned structure. Accordingly, it is possible not to affect products around the dishwasher  1 , and thus the service satisfaction of the consumer may be increased. 
       FIG.  10    is an enlarged view illustrating a state in which a flow meter is mounted on a part D of  FIG.  4   .  FIG.  11    is an exploded view of the flow meter of  FIG.  10   . 
     Referring to  FIGS.  10  and  11   , the water tank  100  may include the flow meter  110 . The flow meter  110  may be mounted on a flow meter installation member  140  of the first case  200 . The flow meter installation member  140  may include an accommodation space  142  to accommodate the flow meter  110 . The flow meter  110  is installed on the first flow path  231  to detect the flow rate of the washing water supplied from the water supplier  131 . 
     The flow meter  110  may include an impeller  113 , a body  111 , and a printed circuit board (PCB)  112 . 
     The body  111  may include a flow path hole  111   a  forming the flow path  231  and provided to allow washing water to be supplied from the water supplier and to flow. The body  111  may include a PCB mounting member  111   b  on which the PCB  112  is mounted. In addition, the body  111  may include a PCB fixing protrusion  111   c  provided to fix a position of the PCB  112 . Accordingly, the PCB  112  may be detachably mounted on the body  111 . 
     The PCB mounting member  111   b  may be formed on an upper surface of the body  111 . The PCB  112  may be mounted on the upper surface of the body  111  such that a portion of the PCB  112  is exposed to the outside of the water tank  100 . The PCB  112  may be connected to a wire for receiving power from the outside and sending and receiving signals. 
     The impeller  113  may be accommodated in the body  111 . The impeller  113  may be mounted on an impeller mounting member  141  of the first case  200 . The impeller  113  may include a magnet seating member  113   a . The impeller  113  may be rotated by the supplied washing water. Through a magnet (not shown) mounted on the impeller  113 , a signal regarding a rotation speed of the impeller  113  may be transmitted to the PCB  112  so as to detect the flow rate. 
       FIG.  12    is a view illustrating a state in which a folding flange is not folded in the water tank of the dishwasher according to one embodiment of the present disclosure.  FIG.  13    is a view illustrating a state in which the folding flange of  FIG.  12    is folded. 
     Referring to  FIGS.  10  to  13   , the second case  300  may cover the flow meter  110  mounted on the first case  200 . The second case  300  may be provided to fix the position of the flow meter  110  accommodated in the first case  200 . Particularly, the second case  300  may include a cover  310  provided to cover a portion of the flow meter  110 . 
     The second case  300  may include a folding flange  320 . The folding flange  320  is provided to be foldable. The folding flange  320  may be integrally formed with the second case  300 . 
     The folding flange  320  may include a hook  321 . The hook  321  may be formed at one end of the folding flange  320 . The hook  321  may be coupled to the cover  310  to allow the folding flange  320  to cover the flowmeter  110 . 
     The folding flange  320  may include a protector  322  extending in the same direction as the hook  321 . When the folding flange  320  is folded, the extension  221  may cover a portion of a space between the PCB  112  and the second case  300  so as to protect the PCB  112 . 
     The folding flange  320  may include a folding member  323 . The folding member  323  may be formed to be deformable to allow the folding flange  320  to be folded. 
     The cover  310  may include a hook insertion hole  311 . When the folding flange  320  is in a folded state, the hook  321  may be inserted into the hook insertion hole  311 . 
     The second case  300  may include an opening  330  provided adjacent to the cover  310 . The opening  330  may be formed by cutting a portion of the second case  300 . Through the opening  330 , the PCB  112  of the flow meter  110  may be exposed to the outside. Accordingly, the PCB  112  exposed through the opening  330  may be connected to a wire. 
     As illustrated in  FIGS.  3 ,  12  and  13   , the second case  300  may include a wire hanger  340  connected to the opening  330 . The wire hanger  340  may be formed by cutting a portion of the second case  300 . The wire hanger  340  may be cut from the opening  330  toward the lower portion of the water tank  100 . 
     A wire groove  350  may be formed between the opening  330  and the wire hanger  340 . The wire groove  350  may be formed by cutting a portion of the second case  300  to the rear side. A position of the wire connected to the PCB  112  may be temporarily fixed through the wire groove  350 . Accordingly, the wire hanger  340  may be formed to guide the wire connected to the PCB  112 . 
     The second case  300  may include a guard  360 . The guard  360  may protrude from an outer surface of the second case  300  to prevent moisture from penetrating into the PCB  112 . 
       FIG.  14    is a cross-sectional view taken along line A-A′ of  FIG.  13   , illustrating a state in which the folding flange is not folded.  FIG.  15    is a view illustrating a state in which the folding flange of  FIG.  14    is folded. 
     Referring to  FIGS.  14  and  15   , the hook  321  of the folding flange  320  may include a connector  321   b  and a locker  321   a . The connector  321   b  may extend to the outside of the folding flange  320  by approximately a thickness of the second case  300 . The locker  321   a  may be formed at one end of the connector  321   b . In the folded state of the folding flange  320 , the locker  321   a  passes through the hook insertion hole  311  of the cover  310  and is caught by the cover  310 . 
     The hook  321  may further include a flat member  321   c . The flat member  321   c  may be provided on the locker  321   a . The water tank  100  according to the present disclosure is generally formed by injection molding. Because the hook  321  includes the flat member  321   c , a mold for injection molding the hook  321  may be provided in a vertical separation structure. In other words, a separate slide core is not required and the mold is formed by separating only upper and lower parts of the mold. Accordingly, it is possible to reduce a mold manufacturing cost. 
     The PCB  112  of the flow meter  110  is typically fused together inside the water tank  100 . Accordingly, when a defect or malfunction occurs, it is impossible to only replace the PCB  112 , but it is required to replace the entire water tank  100 . 
     However, according to the present disclosure, because the folding flange  320  is formed in the water tank  100 , a user or an engineer can selectively release the coupling between the folding flange  320  and the cover  310 . 
     Accordingly, when a user removes the hook  321  of the folding flange  320  from the cover  310  by using a simple tool on the outside of the dishwasher  1 , the user can access the PCB  112 . Accordingly, it is possible to easily replace only the PCB  112  and thus it is possible to reduce a repair cost and a service cost. 
     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.