Patent Publication Number: US-11382483-B2

Title: Dishwasher

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a National Stage application under 35 U.S.C. § 371 of International Application No. PCT/KR2019/001567, filed on Feb. 8, 2019, which claims the benefit of Korean Application No. 10-2018-0015783, filed on Feb. 8, 2018. The disclosures of the prior applications are incorporated by reference in their entirety. 
     TECHNICAL FIELD 
     The present disclosure relates to a dishwasher and, more particularly, to a dishwasher that washes dishes or cooking utensils by spraying wash water and steam. 
     BACKGROUND ART 
     A dishwasher is a home appliance that washes dishes or cooking utensils, etc. (hereinafter referred to as a ‘cleaning target’) to remove waste such as food residues therefrom by high-pressure wash water sprayed from a spray arm. 
     The dishwasher washes the cleaning target using heated wash water or performs a washing operation or a sterilizing operation by supplying steam to the cleaning target. A structure where a heater is installed in a wash pump to efficiently generate steam has been proposed. In addition, a structure where a steam nozzle for spraying steam is disposed on a lower end of a door so that steam is efficiently applied to the cleaning target has been proposed (Korean Patent Laid-Open Publication No. 10-2017-0016180). 
     When steam is generated, bubbles surrounding gas-phase steam with liquid-phase water in the form of a thin film are created. There is a problem that a flow velocity in the steam path is reduced, while the bubbles created as such move along a steam path together with the steam. 
     Furthermore, there is a problem that the bubbles are burst while the bubbles move along the steam path, so that resistance in the steam path is increased and consequently an amount of the steam sprayed from the steam nozzle is reduced. 
     DISCLOSURE 
     Technical Problem 
     The present disclosure proposes a dishwasher that removes bubbles flowing along a steam path, thus increasing an amount of steam sprayed from a steam nozzle. 
     Furthermore, the present disclosure proposes a dishwasher that separates water and steam in a steam path, thus securing the straightness of steam sprayed from a steam nozzle and improving visibility when the steam is sprayed. 
     Furthermore, the present disclosure proposes a dishwasher configuration in which a filter for removing bubbles in a steam path is disposed to achieve the maximum effect. 
     Technical objects to be achieved by the present disclosure are not limited to the aforementioned technical objects, and other technical objects not described above may be evidently understood by a person having ordinary skill in the art to which the present disclosure pertains from the following description. 
     Technical Solution 
     A dishwasher according to an embodiment of the present disclosure may include a case accommodating a cleaning target therein; a sump connected to an interior of the case to collect wash water; a wash pump into which the wash water flows from the sump, and generating steam; a steam nozzle into which the steam flows from the wash pump, and spraying the steam into the case; and a bubble filter disposed on a steam path between the wash pump and the steam nozzle to remove a bubble in the steam path. 
     The bubble filter may include a bubble chamber configured such that a first end thereof is located to be higher than a water level in the wash pump, and a second end thereof is located to be lower than the water level in the wash pump, while the dishwasher is operated in a steam spray mode, and a bubble breaker disposed in the bubble chamber to break the bubble. 
     The bubble breaker may be disposed higher than the water level in the wash pump, while the dishwasher is operated in the steam spray mode. 
     Furthermore, the bubble breaker may include a plurality of breaking plates extending in a direction where the steam flows in the bubble chamber. The plurality of breaking plates may be arranged such that neighboring breaking plates face each other, with a steam flow space being formed between the neighboring breaking plates. 
     According to an embodiment of the present disclosure, the bubble breaker may form the steam flow space between a breaking plate adjacent to an inner surface of the valve chamber among the plurality of breaking plates and the inner surface of the valve chamber. 
     According to an embodiment of the present disclosure, the bubble breaker may include a pair of guide protrusions on both sides thereof that face each other. 
     The bubble chamber may include a pair of guide grooves into which the pair of guide protrusions is inserted, so that the bubble breaker may be slidably coupled to the bubble chamber. 
     According to an embodiment of the present disclosure, the bubble breaker may include a first connecting plate connecting first sides of the plurality of breaking plates to each other, and a second connecting plate connecting second sides of the plurality of breaking plates to each other. Each of the first connecting plate and the second connecting plate may include a guide protrusion. 
     According to an embodiment of the present disclosure, the bubble chamber may include a bubble-chamber upper member and a bubble-chamber lower member. The bubble breaker may be disposed between a bubble-chamber upper member and a bubble-chamber lower member. Furthermore, the bubble breaker may be supported upwards by the bubble-chamber lower member, and be supported downwards by the bubble-chamber upper member. 
     According to an embodiment of the present disclosure, the dishwasher may further include a steam hose connecting the bubble filter and the steam nozzle. The bubble filter may be coupled at a first end thereof to the wash pump, and coupled at a second end thereof to the steam hose. 
     According to an embodiment of the present disclosure, the bubble filter may be disposed on a base of the case, on which the sump and the wash pump are disposed. 
     Specific details of other embodiments are included in the detailed description and drawings. 
     Advantageous Effects 
     A dishwasher according to the present disclosure has one or more effects as follows. 
     First, it is advantageous in that only steam moves to a steam nozzle by removing bubbles flowing along a steam path, thus increasing an amount of the steam sprayed from a steam nozzle. 
     Second, it is advantageous in that water and steam in a steam path are separated, so that flow resistance in the steam path is reduced, thus securing the straightness of steam sprayed from a steam nozzle and improving visibility when the steam is sprayed. 
     Third, it is advantageous in that a bubble filter is coupled to a wash pump in which steam is generated, so that the bubble filter can effectively remove bubbles in a beginning part of a steam path. 
     Effects which may be obtained by the present disclosure are not limited to the aforementioned effects, and other technical effects not described above may be evidently understood by a person having ordinary skill in the art to which the present disclosure pertains from the following description. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a diagram illustrating a schematic structure of a dishwasher in accordance with an embodiment of the present disclosure. 
         FIG. 2  is a diagram illustrating a configuration of the dishwasher in accordance with the embodiment of the present disclosure. 
         FIG. 3  is a schematic view illustrating the steam spray of the dishwasher in accordance with the embodiment of the present disclosure. 
         FIG. 4  is an exploded perspective view of a bubble filter of the dishwasher in accordance with the embodiment of the present disclosure. 
         FIG. 5  is a front view of the bubble filter of the dishwasher in accordance with the embodiment of the present disclosure. 
         FIG. 6  is a rear view of the bubble filter of the dishwasher in accordance with the embodiment of the present disclosure. 
         FIG. 7  is a sectional view of the bubble filter of the dishwasher in accordance with the embodiment of the present disclosure. 
         FIG. 8  is a diagram illustrating a bubble-chamber upper member and a bubble breaker of the dishwasher in accordance with the embodiment of the present disclosure, when seen from above. 
         FIGS. 9 and 10  are diagrams illustrating a portion of the configuration of the dishwasher in accordance with the embodiment of the present disclosure. 
     
    
    
     MODE FOR INVENTION 
     The above and other objects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description when taken in conjunction with the accompanying drawings. However, it is to be understood that the present disclosure may be embodied in many different forms without being limited to embodiments which will be described later. These embodiments are intended to make the disclosure of the invention complete. The present disclosure will be described to be understood by a person having ordinary skill in the art to which the present disclosure pertains. 
     Hereinafter, the terms “front (F)/rear (R)/left (Le)/right (Ri)/up (U)/down (D)” may be defined as shown in the drawings. However, they are merely used for the convenience of description. The terms “front (F)/rear (R)/left (Le)/right (Ri)/up (U)/down (D)” may be defined differently from those designated in the drawings. 
       FIG. 1  is a diagram illustrating a schematic structure of a dishwasher in accordance with an embodiment of the present disclosure. 
       FIG. 2  is a diagram illustrating a configuration of the dishwasher in accordance with the embodiment of the present disclosure. 
     The dishwasher  1  in accordance with the embodiment of the present disclosure a case  11  which defines an appearance thereof, a tub  12  which is provided in the case  11  and defines a wash chamber  12   a  accommodating a cleaning target therein, a door  20  which is provided on a front of the tub  12  to open or close the wash chamber  12   a , a sump  100  which is disposed under the tub  12  to store wash water, a plurality of spray arms  13 ,  14 , and  15  which sprays wash water into the tub  12 , a wash pump  150  which supplies the wash water stored in the sump  100  to the plurality of spray arms  13 ,  14 , and  15  to generate steam, a steam nozzle  195  which sprays the steam generated in the wash pump  150  to the wash chamber  12   a , a bubble filter  200  which is disposed on a steam path between the wash pump  150  and the steam nozzle  195  to remove bubbles in the steam path, a steam hose  190  which connects the wash pump  150  and the steam nozzle  195  or the bubble filter  200  and the steam nozzle  195 , and a switch valve  130  which is disposed on the sump  100  to distribute wash water to the plurality of spray arms  13 ,  14 , and  15 . 
     The case  11  may accommodate dishes which are the cleaning target. The case  11  may accommodate the tub  12  and all of components of the dishwasher  1 . 
     The tub  12  is formed in the shape of a hexahedron which is opened at the front, and defines a wash chamber  12   a  therein. A communication hole  12   c  is formed in a bottom  12   b  of the tub  12  so that wash water flows into the sump  100 . The wash chamber  12   a  is provided with a plurality of racks  16  and  17  to receive the cleaning target. The plurality of racks  16  and  17  includes a lower rack  16  disposed in a lower portion of the wash chamber  12   a , and an upper rack  17  disposed in an upper portion of the wash chamber. The lower rack  16  and the upper rack  17  may be vertically disposed to be spaced apart from each other, and may be taken out from the tub  12  by sliding forwards. 
     The plurality of spray arms  13 ,  14 , and  15  is vertically disposed. The plurality of spray arms  13 ,  14 , and  15  includes a lower spray arm  13  which is disposed on a lowermost portion to spray wash water towards the lower rack  16  from bottom to top, an upper spray arm  14  which is disposed above the lower spray arm  13  to spray wash water towards the upper rack  17  from bottom to top, and a top spray arm  15  which is disposed on an upper end of the wash chamber  12   a  that is an upper side of the upper spray arm  14  to spray wash water from top to bottom. 
     The plurality of spray arms  13 ,  14 , and  15  is supplied with wash water through a plurality of spray arm connecting paths  18 ,  19 , and  21  from the wash pump  150 . The plurality of spray arm connecting paths  18 ,  19 , and  21  includes a lower spray arm connecting path  18  connected to the lower spray arm  13 , an upper spray arm connecting path  19  connected to the upper spray arm  14 , and a top spray arm connecting path  21  connected to the top spray arm  15 . 
     The sump  100  is disposed under the bottom  12   b  of the tub  12  to collect the wash water. The sump  100  is connected to a water supply path  23  through which the wash water supplied from an external water source flows. A water supply valve  22  is provided on the water supply path  23  to regulate the wash water supplied from the external water source. If the water supply valve  22  is opened, the wash water supplied from the external water source flows through the water supply path  23  into the sump  100 . A flowmeter  27  is provided on the water supply path  23  to measure the flow rate of the wash water flowing through the water supply path  23  to the sump  100 . 
     The sump  100  is connected to a drain path  24  which guides the stored wash water to an outside of the dishwasher  1 . A drain pump  25  is provided on the drain path  24  to drain the wash water in the sump  100  through the drain path  24 . If the drain pump  25  is driven, the wash water stored in the sump  100  flows through the drain path  24  to the outside of the case  11 . 
     A filter  26  is mounted in the communication hole  12   c  to filter waste from the wash water which flows from the tub  12  to the sump  100 . 
     The wash pump  150  supplies the wash water stored in the sump  100  to at least one of the plurality of spray arms  13 ,  14 , and  15 . The wash pump  150  is connected to the switch valve  130  via a wash-water supply path  180 . If the wash pump  150  is driven, the wash water stored in the sump  100  flows through a water collecting path  170  into the wash pump  150 , and then is pumped through the wash-water supply path  180  to the switch valve  130 . 
     The wash pump  150  may heat the wash water transferred to the wash-water supply path  180 . The wash pump  150  heats the wash water stored therein to generate steam. The wash pump  150  is connected to the steam hose  190 . The steam generated in the wash pump  150  is supplied through the steam hose  190  to the steam nozzle  195 . 
     The wash pump  150  is installed on aside of the sump  100 . Since the wash pump  150  may use any one of conventional known pumps, a detailed description of the wash pump  150  will be omitted herein. 
     The heater  140  is coupled to a lower side of the wash pump  150  to heat the wash water in the wash pump  150 . The heater  140  heats the wash water flowing in the wash pump  150  when the wash pump  150  is operated, thus generating hot water. The heater  140  heats the wash water stored in the wash pump  150  when the wash pump  150  is stopped, thus generating steam. 
     The hot water generated by the heater  140  is sprayed into the tub  12  through at least one of the plurality of spray arms  13 ,  14 , and  15 . The steam generated by the heater  140  flows along the steam hose  190  and then is discharged through the steam nozzle  195  into the tub  12 . 
     The bubble filter  200  may be disposed on the steam path between the wash pump  150  and the steam nozzle  195 . The bubble filter  200  may include a bubble chamber  210 ,  220  which holds the steam and the wash water therein, and a bubble breaker  230  which is disposed in the bubble chamber  210 ,  220  to break the bubble. The bubble filter  200  may break the bubble passing through the bubble filter  200 , so that water in the liquid phase may be accumulated in the bubble chamber  210 ,  220 , and steam in the gas phase may flow along the steam path into the steam nozzle  195 . The bubble filter  200  will be described later in detail with reference to  FIG. 3  and the like. 
     The steam nozzle  195  is provided on the lower end of the door  20  to spray the steam to the wash chamber  12   a . The steam sprayed from the steam nozzle  195  acts on the cleaning target received in the lower rack  16  and/or the upper rack  17 . 
     The switch valve  130  selectively connects the sump  100  to at least one of the plurality of spray arms  13 ,  14 , and  15 . The switch valve  130  selectively supplies the wash water pumped by the wash pump  150  to at least one of the lower spray arm  13 , the upper spray arm  14 , and the top spray arm  15 . The switch valve  130  selectively connects the wash-water supply path  180  to at least one of the plurality of spray arm connecting paths  18 ,  19 , and  21 . 
     A check valve  175  is disposed between the sump  100  and the wash pump  150  to be opened in a direction from the sump  100  to the wash pump  150 . The check valve  175  is opened so that the wash water flows from the sump  100  to the wash pump  150 , and is closed so that the steam does not flow from the wash pump  150  to the sump  100 . A lower portion of the check valve  175  rotates about an upper portion, so that the check valve is opened. The check valve  175  is disposed in the water collecting path  170  or connects the water collecting path  170  and the wash pump  150  to open or close the water collecting path  170 . 
     The check valve  175  is closed when the heater  140  generates the steam. The check valve  175  is opened when the wash pump  150  is operated, so that the wash water flows, and is closed when the wash pump  150  is stopped, so that the wash water does not flow. The check valve  175  is opened by the flow pressure of the wash water of the wash pump  150 . According to an embodiment, the check valve  175  may be a solenoid valve that is opened or closed by an electronic signal. 
     The check valve  175  is formed so that the wash water flows from the wash pump  150  to the sump  100 , even when the check valve is closed during the operation of the drain pump  25 . 
       FIG. 3  is a schematic view illustrating the steam spray of the dishwasher in accordance with the embodiment of the present disclosure. 
     Referring to  FIG. 3 , the wash pump  150  may be connected to a water collector  102  of the sump  100  via a water collecting pipe, so that water may be introduced from the water collector  102 . 
     The bubble chamber  210 ,  220  may be coupled at a lower end to the wash pump  150 , so that wash water and/or steam may be introduced from the wash pump  150 . The bubble chamber  210 ,  220  may be connected to a negative-pressure part of the wash pump  150 . 
     The negative-pressure part of the wash pump  150  is a part in which negative pressure is generated when a pump motor is operated, and may be defined as a part which stores wash water introduced into a wash motor. The negative-pressure part of the wash pump  150  may be distinguished from a positive-pressure part of the wash pump  150  which discharges the wash water pumped by the wash pump  150 . 
     Meanwhile, although not shown in the drawings, the bubble filter  200  may not be directly connected to the wash pump  150 , but may be connected thereto via a hose. 
     If water is accommodated in the water collector  102  of the sump  100 , water may also be accommodated in the wash pump  150  and the bubble filter  200  connected to the wash pump  150 . In this case, a water level in the wash pump  150  and the bubble filter  200  may be the same as a water level of the water collector  102 . 
     The bubble filter  200  may include the bubble breaker  230 , and the bubble chamber  210 ,  220  defining internal space in which wash water is accommodated. 
     While the dishwasher  1  is operated in a steam spray mode, one end (upper end) of the bubble chamber  210 ,  220  may be located to be higher than the water level in the wash pump  150 , and the other end (lower end) may be located to be lower than the water level in the wash pump  150 . In other words, the bubble chamber  210 ,  220  may accommodate the wash water up to a medium height in the chambers. 
     The heater  140  may heat wash water in a state where the wash water is accommodated in the wash pump  150 , thus generating steam. The generated steam may be introduced into the bubble filter  200 . Alternatively, steam may be generated in the bubble filter  200  by the heat generated by the heater  140 . 
     For example, if the heater  140  is turned on in a state where wash water is accommodated in the bubble filter  200 , the wash water in the wash pump  150  as well as the wash water in the bubble filter  200  may be heated. If the wash water in the wash pump  150  first reaches 100 degrees Celsius to generate steam, the steam may flow through the discharge pipe of the wash pump  150  to the bubble filter  200 . At this time, the bubble may be introduced from the wash pump  150  to the bubble filter  200 . 
     For example, if the heater  140  is turned on in a state where wash water is accommodated in the bubble filter  200 , so that the wash water in the bubble filter  200  reaches 100 degrees Celsius, steam may be generated in the bubble filter  200 . At this time, bubbles surrounding the steam with liquid-phase water may be generated together. 
     The steam and/or bubble generated in the bubble filter  200  or introduced into the bubble filter  200  may flow along the bubble filter  200 . 
     The steam may flow along the steam path. The steam path may include the bubble chamber  210 ,  220 , the steam path, and a path in the steam nozzle, and may be defined to refer to all passages through which the steam passes. 
     The bubble breaker  230  may be disposed in the bubble chamber  210 ,  220  to be higher than the wash water. While the dishwasher  1  is operated in the steam spray mode, the bubble breaker  230  may be disposed in the bubble chamber  210 ,  220  to be higher than the level of the wash water in the bubble chamber  210 ,  220 . 
     The bubble breaker  230  may break the bubble which is introduced into the bubble breaker  230  while flowing along the bubble chamber  210 ,  220 . The bubble may be defined as a shape of a sphere formed by surrounding air or gas with a thin liquid film. The bubble breaker  230  may break the bubble so that gas (or air) in liquid comes out of the bubble. 
     The bubble breaker  230  may break the bubble by causing the bubble to come into contact with a contact surface of the bubble breaker  230 . 
     The bubble breaker  230  may break the bubble, so that the gas-phase steam may pass through the bubble breaker  230  and the liquid-phase water may not pass through the bubble breaker  230 . 
     The steam passing through the bubble breaker  230  may flow to the upper end of the bubble chamber  210 ,  220  to be discharged through a bubble-chamber outlet  211  to the steam hose  190 . 
     The steam hose  190  may connect the bubble filter  200  and the steam nozzle  195 , thus guiding the steam discharged from the bubble filter  200  to the steam nozzle  195 . 
     The steam nozzle  195  may spray the steam into the wash chamber  12   a.    
     The bubble filter  200  configured as such may remove the bubble in the steam path, and cause the steam to effectively flow along the steam path, thus improving the flowability of the steam. 
     In other words, when the steam moves along the steam path in a bubble state, the mobility of the steam may be reduced. When the bubble moving along the steam path is broken and water forms in the steam path, the path resistance of the steam path may be increased. 
     The bubble filter  200  filters the bubble, generated in the wash pump  150 , in the bubble chamber  210 ,  220  which is a beginning part of the steam path, thus allowing the gas-phase steam to move along the steam path. 
     Furthermore, the bubble filter  200  configured as such prevents the bubble from being sprayed when the steam is sprayed from the steam nozzle  195 , thus allowing the steam to be effectively sprayed. 
     In other words, if the steam and the bubble are sprayed from the steam nozzle  195  in a mixed state, a spray distance in the tub  12  may be reduced as compared with when only the steam is sprayed. Furthermore, when steam and water drops are mixed and sprayed from the steam nozzle  195 , the spray amount of the steam may also be reduced. 
     The bubble filter  200  may break the bubble in the bubble chamber  210 ,  220  to capture water drops and cause steam to pass therethrough, so that the spray amount of the steam from the steam nozzle  195  may be increased, and the spray range of the steam may also be enhanced. 
     Meanwhile, the bubble filter  200  may minimize a curve part of the steam path and thereby minimize a pressure loss. 
     When the steam hose  190  connects the wash pump  150  and the steam nozzle  195  without the bubble filter  200 , the steam hose  190  includes a plurality of bent curve parts. The curved path is a point in which a difference in rotating radius of fluid flowing along the path is large, and may have a larger hydraulic loss compared to a straight path. 
     Since the bubble filter  200  is connected to the wash pump  150  and steam is created in the bubble filter  200 , the flow distance of the steam may be reduced, and in addition, the number of curved paths may be reduced. 
     By way of example, since a bubble-chamber inlet  221  of the bubble-chamber lower member  220  is formed in a curved path and steam is formed in the middle of the bubble chamber  210 ,  220 , the steam does not pass through the bubble-chamber inlet  221  and the bubble-chamber lower member  220  and the number of the curve parts of the steam path may be reduced. 
     The dishwasher  1  may be set such that the water level in the water collector  102 , the wash pump  150 , and the bubble chamber  210 ,  220  is above a certain height in the steam spray mode. In the state where wash water is stored in the bubble chamber  210 ,  220 , the wash water may be heated by the heater  140 , thus generating steam. When the wash water reaches 100 degrees in the bubble chamber  210 ,  220 , the steam may be generated. At this time, the steam may be generated at the surface of the wash water. 
     Therefore, as the level of the wash water increases, a distance the generated steam moves to the steam nozzle may be reduced. In the state where the level of the wash water in the bubble chamber  210 ,  220  of the bubble filter  200  is above a certain height, steam may be effectively generated. 
       FIG. 4  is an exploded perspective view of the bubble filter of the dishwasher in accordance with the embodiment of the present disclosure. 
       FIG. 5  is a front view of the bubble filter of the dishwasher in accordance with the embodiment of the present disclosure. 
       FIG. 6  is a rear view of the bubble filter of the dishwasher in accordance with the embodiment of the present disclosure. 
       FIG. 7  is a sectional view of the bubble filter of the dishwasher in accordance with the embodiment of the present disclosure. 
       FIG. 8  is a diagram illustrating a bubble-chamber upper member and the bubble breaker of the dishwasher in accordance with the embodiment of the present disclosure, when seen from above. 
     Referring to  FIG. 4 , the bubble filter  200  may include the bubble chamber  210 ,  220  whose one end is located to be higher than the water level in the wash pump  150  and the other end is located to be lower than the water level in the wash pump  150 , while the dishwasher  1  is operated in the steam spray mode. The bubble filter  0  may include the bubble breaker  230  which is disposed in the bubble chamber  210 ,  220  to break the bubble. 
     The dishwasher  1  may be operated in any one of the plurality of spray modes including the wash-water spray mode in which wash water is sprayed through the plurality of spray arms  13 ,  14 , and  15 , and the steam spray mode in which steam is sprayed through the steam nozzle  195 . 
     The bubble chamber  210 ,  220  may be generally provided in the shape of a bar that extends vertically to a predetermined length. The bubble chamber  210 ,  220  may have the shape of a polygonal container that defines a space therein. 
     The bubble chamber  210 ,  220  may include the bubble-chamber upper member  210  and the bubble-chamber lower member  220 . The bubble-chamber upper member  210  and the bubble-chamber lower member  220  vertically combine each other, thus defining the appearance of the bubble filter  200 . 
     The bubble chamber  210 ,  220  may be formed of a material having low strain at high temperature. The bubble chamber  210 ,  220  may be formed of a material that may be resistant to heat, while the wash water contained therein is heated up to 100 degrees by the heater  140 . The bubble chamber  210 ,  220  may be formed of a material whose heat conductivity is a predetermined level or less. The bubble chamber  210 ,  220  may be formed of a material whose thermal expansion coefficient is a predetermined level or less. 
     The bubble-chamber upper member  210  may have on a lower end thereof a coupler which couples the bubble-chamber upper member to the bubble-chamber lower member  220 . The bubble-chamber upper member  210  may include a coupled which protrudes downwards to be inserted into the bubble-chamber lower member  220 . 
     The bubble-chamber upper member  210  may have a bubble-chamber outlet  211  through which the steam in the bubble chamber  210 ,  220  is discharged. The bubble-chamber outlet  211  may be a pipe which extends to the front of the bubble-chamber upper member  210 . 
     One end of the bubble-chamber outlet  211  may communicate with the interior of the bubble chamber  210 ,  220 , and the other end may communicate with the exterior of the bubble chamber  210 ,  220 . The bubble-chamber outlet  211  may be coupled to the steam hose  190  to discharge the steam in the bubble chamber  210 ,  220  to the steam hose  190 . 
     The bubble-chamber outlet  211  may be provided on an upper end of the bubble-chamber upper member  210 , so that an upper surface of the bubble-chamber upper member  210  may be connected to an inner surface of the bubble-chamber outlet  211 . Thereby, it is possible to reduce path resistance acting on steam flowing in the bubble chamber  210 ,  220 . 
     An inner surface of the bubble-chamber outlet  211  which is connected to an inner surface of the bubble-chamber upper member  210  is rounded, thus ensuring smooth connection. Thereby, it is possible to reduce path resistance acting on steam introduced into the bubble-chamber outlet  211 . Furthermore, stress acting on a portion at which the bubble-chamber outlet  211  and the bubble-chamber upper member  210  are connected is dispersed, thus improving durability. 
     The upper end of the bubble-chamber upper member  210  is inclined downwards towards the rear, so that it is possible to reduce path resistance acting on the flow of the steam introduced into the bubble-chamber outlet  211  in the bubble chamber  210 ,  220 . 
     The bubble-chamber lower member  220  may be provided with the bubble-chamber inlet  221  through which wash water flows into the bubble chamber  210 ,  220 . The bubble-chamber inlet  221  may be a pipe extending to the rear of the bubble-chamber lower member  220 . 
     One end of the bubble-chamber inlet  221  may communicate with the interior of the bubble chamber  210 ,  220 , and the other end may communicate with the exterior of the bubble chamber  210 ,  220 . The bubble-chamber inlet  221  may be coupled to the wash pump  150 , so that wash water in the wash pump  150  may be introduced into the bubble filter  200 . 
     The bubble-chamber inlet  221  may be provided on the lower end of the bubble-chamber lower member  220 , so that the lower surface of the bubble-chamber lower member  220  may be connected to the inner surface of the bubble-chamber inlet  221 . Thereby, it is possible to reduce path resistance acting on wash water flowing in the bubble chamber  210 ,  220 . 
     An inner surface of the bubble-chamber inlet  221  which is connected to an inner surface of the bubble-chamber lower member  220  is rounded, thus ensuring smooth connection. Thereby, it is possible to reduce path resistance acting on wash water flowing from the bubble-chamber inlet  221  into the bubble chamber  210 ,  220 . 
     Furthermore, stress acting on a portion at which the bubble-chamber inlet  221  and the bubble-chamber lower member  220  are connected is dispersed, thus improving durability. 
     The bubble-chamber lower member  220  may have on an upper end thereof a coupler which couples the bubble-chamber lower member to the bubble-chamber upper member  210 . 
     Referring to  FIG. 7 , the bubble-chamber lower member  220  may include the coupler  224  that is shaped to engage with the coupler  212  of the bubble-chamber upper member  210 . The bubble-chamber upper member  210  may be partially inserted into the bubble-chamber lower member  220  to be coupled thereto. The bubble-chamber upper member  210  may be partially inserted into the interior of the bubble-chamber lower member  220  to be coupled thereto. 
     The bubble-chamber lower member  220  may be provided with a stopper  222  which guides the coupling height of the bubble-chamber upper member  210 . 
     The stopper  222  may have the shape of a step formed on the upper end of the bubble-chamber lower member  220 . The stopper  222  may be in contact with the lower end of the coupler  212  of the bubble-chamber upper member  210  to support the bubble-chamber upper member  210  upwards. 
     The bubble-chamber lower member  220  may include the coupler  224  which surrounds the outside of the coupler  212  of the bubble-chamber upper member  210 . The coupler  224  may be connected to the stopper  222 , thus covering the outside of the coupler  212  of the bubble-chamber upper member  210  seated on the stopper. 
     Thereby, the bubble-chamber upper member  210  and the bubble-chamber lower member  220  are provided in a crossing shape to be coupled to each other, thus sealing the bubble chamber  210 ,  220  so that fluid contained therein does not leak out from the bubble chamber  210 ,  220 . 
     The bubble-chamber lower member  220  may include a pair of guide grooves  223   a  and  223   b  into which a pair of guide protrusions  234   a  and  234   b  that will be described later is inserted. The pair of guide grooves  223   a  and  223   b  may guide an insert position so that the bubble breaker  230  is vertically inserted. 
     The pair of guide grooves  223   a  and  223   b  may be formed on the inner surface of the bubble-chamber lower member  220 , and be grooves which are recessed below the stopper  222 . 
     The pair of guide grooves  223   a  and  223   b  may be provided on front and rear portions to face each other. 
     The bubble breaker  230  may be provided in the bubble chamber  210 ,  220  to be located higher than the water level in the bubble chamber  210 ,  220  while the dishwasher  1  is operated in the steam spray mode. 
     The dishwasher  1  may be set such that the water level in the sump  100  and the wash pump  150  in the steam spray mode is higher than the water level in the sump  100  and the wash pump  150  in the wash-water spray mode. The dishwasher  1  may be set such that the water level in the sump  100  and the wash pump  150  in the wash-water spray mode is lower than that in the steam spray mode, thus allowing the wash motor to effectively convey the wash water in the wash-water spray mode. 
     The bubble breaker  230  may be disposed higher than the water level of the wash water to break the bubble which is generated at the surface of the wash water and then introduced into the bubble breaker  230 . Since the efficiency of the bubble breaker  230  may be reduced when a portion of the bubble breaker  230  sinks in the wash water, the bubble breaker  230  is preferably disposed higher than the water level of the wash water. 
     The bubble breaker  230  may be formed of a material having low strain at high temperature. The bubble breaker  230  may be formed of a material that may withstand steam or bubble heated to 100 degrees or higher. The bubble breaker  230  may be formed of a material whose heat conductivity is a predetermined level or less. The bubble breaker  230  may be formed of a material whose thermal expansion coefficient is a predetermined level or less. 
     Thereby, it is possible to prevent the bubble breaker  230  from being deformed by heat and changed in placement in the bubble chamber  210 ,  220 . Alternatively, it is possible to prevent the bubble breaker  230  from expanding and thereby prevent the bubble chamber  210 ,  220  from being damaged. 
     Referring to  FIGS. 4 and 8 , the bubble breaker  230  may include a plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  extending in a direction where steam flows in the bubble chamber  210 ,  220 . The steam in the bubble chamber  210 ,  220  may flow from bottom to top along the vertically extending bubble chamber  210 ,  220 . 
     The plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  may be provided in the shape of a plate having a thickness. The plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  may be formed to have a predetermined thickness. 
     The plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  may be formed to have a smooth surface. 
     Although not shown in the drawings, protrusions may be formed on surfaces of the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d , thus increasing a contact surface between the bubble and each breaking plate. Thereby, the bubble may be more effectively broken. 
     Contact surfaces of left and right sides of each of the breaking plates  231   a ,  231   b ,  231   c , and  231   d  coming into contact with the bubble may be formed of a hydrophilic material. Thereby, when the bubble comes into contact with the contact surface of each of the breaking plates  231   a ,  231   b ,  231   c , and  231   d , the bubble may be easily burst. 
     The plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  may be arranged in a front-rear direction or a left-right direction so that neighboring breaking plates  231   a ,  231   b ,  231   c , and  231   d  face each other. Spaces in which steam flows may be formed between neighboring breaking plates  231   a ,  231   b ,  231   c , and  231   d.    
     The plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  may be arranged to be spaced apart from each other by a predetermined interval. 
     For example, the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  may be arranged to be spaced apart from each other by the interval of 3 to 5 mm. 
     Thereby, it is possible to prevent a bubble exceeding a predetermined size from passing between the breaking plates  231   a ,  231   b ,  231   c , and  231   d , and to limit the inflow of wash water between the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d.    
     Among the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d , the breaking plates  231   a  and  231   d  adjacent to the inner surface of the bubble chamber  220  are disposed to be spaced apart from the inner surface of the bubble chamber  220  by a predetermined distance, so that the steam flow space may be formed between the breaking plates  231   a  and  231   d  and the inner surface of the bubble chamber  220 . 
     When the breaking plates  231   a  and  231   d  adjacent to the inner surface of the bubble chamber  220  are provided to be in contact with the inner surface of the bubble chamber  220 , only one of both contact surfaces of the breaking plates  231   a  and  231   d  comes into contact with the bubble, thus reducing bubble removal efficiency. Therefore, the breaking plates  231   a  and  231   d  are disposed to be spaced apart from the inner surface of the bubble chamber  220 , so that both contact surfaces of the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  may come into contact with the bubble. 
     The bubble breaker  230  may include a first connecting plate  232  connecting first sides of the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  to each other. The bubble breaker  230  may include a second connecting plate  233  connecting second sides of the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d  to each other. 
     The first connecting plate  232  may be connected to a front end of each of the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d . The first connecting plate  232  may be formed to have a predetermined thickness in the front-rear direction, and extend vertically. 
     The first connecting plate  232  may be provided with a surface which is in contact with the inner surface of the bubble chamber  210 ,  220 . The first connecting plate  232  may be formed in a shape corresponding to the curvature of the inner surface of the bubble chamber  210 ,  220  to be in close contact with the inner surface of the bubble chamber  210 ,  220 . 
     The second connecting plate  233  may be connected to a rear end of each of the plurality of breaking plates  231   a ,  231   b ,  231   c , and  231   d . The second connecting plate  233  may be formed to have a predetermined thickness in the front-rear direction, and extend vertically. 
     The second connecting plate  233  may be provided with a surface which is in contact with the inner surface of the bubble chamber  210 ,  220 . The second connecting plate  233  may be formed in a shape corresponding to the curvature of the inner surface of the bubble chamber  210 ,  220  to be in close contact with the inner surface of the bubble chamber  210 ,  220 . 
     The bubble breaker  230  may have a pair of guide protrusions  234   a  and  234   b  on both sides facing each other. The pair of guide protrusions  234   a  and  234   b  may be provided on the first connecting plate  232  and the second connecting plate  233 , respectively. 
     The first guide protrusion  234   a  may protrude forwards from the first connecting plate  232 . 
     A vertical length of the first guide protrusion  234   a  may be formed to correspond to a vertical length of the guide groove  223   a . For example, the vertical length of the first guide protrusion  234   a  may be smaller than or equal to the vertical length of the guide groove  223   a.    
     A horizontal length of the first guide protrusion  234   a  may be formed to correspond to a horizontal length of the guide groove  223   a . For example, the horizontal length of the first guide protrusion  234   a  may be smaller than or equal to the horizontal length of the guide groove  223   a.    
     A protruding length of the first guide protrusion  234   a  in the front-rear direction may be formed to correspond to a recessed depth of the guide groove  223   a  in the front-rear direction. For example, the length of the first guide protrusion  234   a  in the front-rear direction may be formed to be smaller than or equal to the length of the guide groove  223   a  in the front-rear direction. 
     The second guide protrusion  234   b  may be provided to be symmetrical with the first guide protrusion  234   a . The second guide protrusion  234   b  and the first guide protrusion  234   a  may be symmetrical with each other in the front-rear direction. 
     The second guide protrusion  234   b  may protrude forwards from the second connecting plate  233 . 
     A vertical length of the second guide protrusion  234   b  may be formed to correspond to a vertical length of the guide groove  223   b . For example, the vertical length of the second guide protrusion  234   b  may be smaller than or equal to the vertical length of the guide groove  223   b.    
     A horizontal length of the second guide protrusion  234   b  may be formed to correspond to a horizontal length of the guide groove  223   b . For example, the horizontal length of the second guide protrusion  234   b  may be smaller than or equal to the horizontal length of the guide groove  223   b.    
     A protruding length of the second guide protrusion  234   b  in the front-rear direction may be formed to correspond to a recessed depth of the guide groove  223   b  in the front-rear direction. For example, the length of the second guide protrusion  234   b  in the front-rear direction may be formed to be smaller than or equal to the length of the guide groove  223   b  in the front-rear direction. 
     Referring to  FIG. 7 , a thickness of the coupler  212  of the bubble-chamber upper member  210  is formed to be greater than a width of the stopper  222  of the bubble-chamber lower member  220 , so that the coupler may protrude inwards further than the inner surface of the stopper  222 . 
     A portion of the coupler  212  of the bubble-chamber upper member  210  which protrudes inwards further than the inner surface of the stopper  222  may support the guide protrusions  234   a  and  234   b  of the bubble breaker  230  downwards. 
     Thereby, the bubble breaker  230  may be secured in place while being vertically supported by the bubble-chamber upper member  210  and the bubble-chamber lower member  220 . 
       FIGS. 9 and 10  are diagrams illustrating a portion of the configuration of the dishwasher in accordance with the embodiment of the present disclosure. 
     Referring to  FIGS. 9 and 10 , the bubble filter  200  may be connected at a lower end thereof to the wash pump  150 , and connected at an upper end thereof to the steam hose  190 . 
     The bubble filter  200  may be coupled to the discharge pipe of the wash pump  150 . The discharge pipe of the wash pump  150  may be a pipe communicating with the steam nozzle  195 . 
     The bubble filter  200  may be coupled to the wash pump  150  by a separate fastening member. The fastening member may be coupled while surrounding an inlet pipe of the bubble filter  200  and the discharge pipe of the wash pump  150 . 
     The bubble filter  200  may be disposed in a vertical direction that is the same as the gravity direction of the bubble chamber  210 ,  220 , thus preventing the bubble chamber  210 ,  220  from being tilted to one side and thereby preventing the wash water in the bubble chamber  210 ,  220  from coming into contact with the bubble breaker  230 . 
     The bubble filter  200  may be disposed on a base  11   a  of the case  11  on which the sump  100  and the wash pump  150  are disposed. 
     The bubble filter  200  may be disposed to be spaced apart from other components adjacent to the bubble chamber outlet  211  by a predetermined distance or more. For example, the bubble filter  200  may be disposed in the base  11   a  so that other components of the dishwasher  1  are not located within 14 mm from an end of the bubble chamber outlet  211 . 
     Thereby, it is possible to secure a space for coupling the bubble chamber outlet  211  to the steam hose  190 . 
     Meanwhile, the bubble filter  200  configured as such may minimize the curve part in the steam path, thus minimizing a pressure loss. 
     When the steam hose  190  connects the wash pump  150  and the steam nozzle  195  without the bubble filter  200 , the steam hose  190  includes a plurality of bent curve parts. The curved path is a point in which a difference in rotating radius of fluid flowing along the path is large, and may have a larger hydraulic loss compared to a straight path. 
     Since the bubble filter  200  is connected to the wash pump  150  and steam is created in the bubble filter  200 , the flow distance of the steam may be reduced, and in addition, the number of curved paths may be reduced. 
     By way of example, since the bubble-chamber inlet  221  of the bubble-chamber lower member  220  is formed in a curved path and steam is formed in the middle of the bubble chamber  210 ,  220 , the steam does not pass through the bubble-chamber inlet  221  and the bubble-chamber lower member  220  and the number of the curve parts of the steam path may be reduced. 
     The dishwasher  1  may be set such that the water level in the water collector  102 , the wash pump  150 , and the bubble chamber  210 ,  220  is above a certain height in the steam spray mode. In the state where wash water is stored in the bubble chamber  210 ,  220 , the wash water may be heated by the heater  140 , thus generating steam. When the wash water reaches 100 degrees in the bubble chamber  210 ,  220 , the steam may be generated. At this time, the steam may be generated at the surface of the wash water. 
     Therefore, as the level of the wash water increases, a distance the generated steam moves to the steam nozzle may be reduced. In the state where the level of the wash water in the bubble chamber  210 ,  220  of the bubble filter  200  is above a certain height, steam may be effectively generated. 
     Although the present disclosure was described with reference to specific embodiments, it is apparent to those skilled in the art that the present disclosure may be changed and modified in various ways without departing from the scope of the present disclosure, which is described in the following claims. 
     
       
         
           
               
             
               
                   
               
               
                 [Description of reference numerals] 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
            
               
                 1: dishwasher 
                 11: case 
               
               
                 12: tub 
                 16, 17: rack 
               
               
                 20: door 
                 100: sump 
               
               
                 130: switch valve 
                 23: water supply path 
               
               
                 24: drain path 
                 26: filter 
               
               
                 13, 14, 15: a plurality of spray arms 
               
               
                 18, 19, 21: a plurality of spray-arm connecting 
               
               
                 paths 
               
               
                 140: heater 
                 150: wash pump 
               
               
                 170: water collecting path 
                 175: check valve 
               
               
                 180: wash-water supply path 
                 190: steam hose 
               
               
                 195: steam nozzle 
                 200: bubble filter