Dishwasher

A dishwasher includes: a tub which defines a space in which dishes are washed; a sump which accommodates washing water to be supplied into the tub; and a descaling solution supply device which supplies a descaling solution to the sump, in which the descaling solution supply device includes: a main flow path which guides washing water to be supplied to the sump; a solution accommodating unit which accommodates a descaling agent and has a solution outlet through which washing water, in which the descaling agent is dissolved, is discharged to the main flow path; a solution discharge valve which opens and closes the solution outlet; and a branch flow path which branches off from the main flow path, supplies the washing water into the solution accommodating unit, and has an atmosphere communicating port that communicates with the atmosphere.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Korean Patent Application No. 10-2014-0092097, filed on Jul. 21, 2014 and No. 10-2014-0109907, filed on Aug. 22, 2014 in the Korean Intellectual Property Office, all of which are incorporated by reference in their entirety for all purposes as if fully set forth herein.

BACKGROUND

1. Field of the Disclosure

The present disclosure relates to a washing machine.

A washing machine is an apparatus that washes contaminated objects using water. As a washing machine, there are a laundry washing machine (typically called a laundry machine) for washing laundry such as clothes or bedding, and a dishwasher for washing dishes and/or pots and pans.

Washing water having hardness of 60 ppm or more is generally called hard water, and when the hard water is heated, scale is inevitably formed. Since most of the washing machines perform a process of heating the washing water, there may be various problems due to accumulation of scale in a case in which hard water is not appropriately processed.

An appropriate amount of descaling agent needs to be supplied in order to remove the scale formed in the washing machine, but because a significant amount of formed scale is discharged from the dishwasher together with drained water, the amount of descaling agent, which is actually required, is very small. A required amount of descaling agent needs to be accurately input because there may occur a problem with product reliability when an excessive amount of descaling agent is supplied, and performance in removing scale may deteriorate when a very small amount of descaling agent is supplied. However, it is difficult and very inconvenient for a user to accurately measure a required amount of descaling agent.

Meanwhile, the descaling agent, which remains on the objects that are completely washed, may cause problems when the descaling agent has a component hazardous to humans. Particularly, in a case in which the object to be washed is necessarily and often used in contact with humans, the problem becomes severe because the component of the remaining descaling agent has an adverse effect on health of a human. Therefore, a descaling agent harmless to humans needs to be used in a case in which there is likelihood that the descaling agent remaining on the objects to be washed (laundry, dishes, etc.) in the laundry machine or the dishwasher will be absorbed by humans.

SUMMARY OF THE DISCLOSURE

The present invention has been made to provide a dishwasher which has a function of preventing formation of scale and removing formed scale.

The present invention has also been made to provide a dishwasher capable of quantitatively supplying a descaling agent.

The present invention has also been made to provide a dishwasher capable of quantitatively supplying a descaling solution even though pressure of washing water being supplied to the dishwasher is changed.

The present invention has also been made to provide a dishwasher which supplies a descaling solution made of a material harmless to humans.

The present invention has also been made to provide a washing machine which inputs organic acid harmless to humans as a descaling agent.

The present invention has also been made to provide a washing machine capable of automatically inputting organic acid.

The present invention has also been made to provide a washing machine which inputs organic acid harmless to humans as a descaling agent.

The present invention has also been made to provide a washing machine capable of automatically inputting organic acid.

An exemplary embodiment of the present invention includes a dishwasher comprising: a tub including a space in which dishes are washed; a sump to contain washing water to be supplied into the tub; and a descaling solution supply device to supply a descaling solution to the sump, in which the descaling solution supply device includes: a main flow path to guide washing water to be supplied to the sump; a solution accommodating unit to contain a descaling agent including a solution outlet through which washing water, in which the descaling agent is dissolved, is discharged to the main flow path; a solution discharge valve to open and close the solution outlet; and a branch flow path which branches off from the main flow path, supplies the washing water into the solution accommodating unit, and includes an atmosphere communicating port that communicates with the atmosphere.

The branch flow path may include: an upstream side branch flow path which guides washing water flowing upward from the main flow path; and a downstream side branch flow path which guides the washing water guided downward along the upstream side branch flow path, and wherein a water level in the downstream side branch flow path may be restricted to a predetermined height by atmospheric pressure applied through the atmosphere communicating port. The dishwasher may further include an intermediate flow path through which the washing water discharged from the upstream side branch flow path passes in the process of flowing into the downstream side branch flow path, in which the atmosphere communicating port is formed in the intermediate flow path. The dishwasher may further include a water supply device to supply the washing water to the main flow path, in which the atmosphere communicating port communicates with the atmosphere through the water supply device.

The atmosphere communicating port may be exposed to the atmosphere while the washing water flows into the solution accommodating unit.

An area of an outlet of the upstream side branch flow path may be smaller than an area of an inlet of the downstream side branch flow path. The area of the outlet of the upstream side branch flow path may be equal to or smaller than 1/10 of the area of the inlet of the downstream side branch flow path.

The washing water outlet may be positioned at a position lower than a height to which a water level in the downstream side branch flow path is restricted.

The main flow path may include a solution merging path to guide the washing water downward and then guide the washing water upward.

The solution outlet may be in the solution merging path. A water level in the tub may be restricted to be below a height to which a water level in the downstream side branch flow path is restricted. An outlet, through which the washing water is discharged, may be in the tub at a position below the height to which the water level in the downstream side branch flow path is restricted.

The descaling solution supply device may include: an accommodating unit main body including the solution accommodating unit and the main flow path; and a main body cover coupled to the accommodating unit main body and forms the branch flow path. The solution accommodating unit may be open at an upper side thereof, and the main body cover may cover the upper side of the solution accommodating unit. The accommodating unit main body and the main body cover may be separably coupled to each other.

A washing water inlet through which the washing water flows into the main flow path may be included in the main body cover.

A descaling agent input opening, which communicates with the solution accommodating unit, may be included in the main body cover, and a stopper may be opens and closes the descaling agent input opening.

The dishwasher may further include a residual quantity detecting sensor to detect a quantity of residual descaling agents in the solution accommodating unit. The residual quantity detecting sensor may detect a change in concentration of the descaling solution.

The dishwasher may further include: an information device; and a controller which determines when to supplement the descaling agent based on a value detected by the residual quantity detecting sensor, and controls the information device to display that it is time to supplement the descaling agent. The dishwasher may further include: a partition which divides the inside of the solution accommodating unit into a space into which the descaling agent is input and a space in which the residual quantity detecting sensor is disposed, in which the partition has a through hole which allows the washing water to flow between the two spaces.

The descaling agent may include organic acid in the form of particles or powder. The organic acid may include one or more kinds of acid selected from a group consisting of citric acid, malic acid, tartaric acid, acetic acid, lactic acid, and formic acid.

The dishwasher may further include a sterilizing device to sterilize washing water accommodated in the solution accommodating unit. The sterilizing device may discharge antimicrobial materials into washing water.

The sterilizing device may emit ultraviolet rays into washing water.

The dishwasher may further include a controller which controls the solution discharge valve. The controller may control the solution discharge valve so that the solution discharge valve is opened based on the number of cycles performed including a series of processes.

The controller may control the solution discharge valve so that the solution discharge valve is opened each time a cycle including a series of processes is carried out.

The dishwasher may further include: an input unit to receive a predetermined course for inputting the descaling agent that is selected by a user; and a controller to control the solution discharge valve so that when the predetermined course is selected by using the input unit, the solution discharge valve is opened while the predetermined course is carried out. The input unit may provide the predetermined course separately from a washing course and a rinsing course.

The dishwasher may further include: a hardness sensor to detect hardness of washing water being supplied from an external water source to the descaling solution supply device; and a controller to set an amount of organic acid, which is input through the descaling agent supply device, based on a value detected by the hardness sensor.

DETAILED DESCRIPTION

Advantages, features and methods for achieving those of embodiments may become apparent upon referring to embodiments described later in detail together with attached drawings. However, embodiments are not limited to the embodiments disclosed hereinafter, but may be embodied in different modes. The embodiments are provided for perfection of disclosure and informing a scope to persons skilled in this field of art. The same reference numbers may refer to the same elements throughout the specification.

FIGS. 1 and 2are block diagrams illustrating a configuration of a washing machine1according to an exemplary embodiment of the present invention. Referring toFIGS. 1 and 2, the washing machine1according to the exemplary embodiment is an apparatus for washing contaminated objects to be washed using washing water. The washing machine may include a washing water accommodating unit20which accommodates washing water supplied for washing the objects to be washed, and a descaling agent supply device100which discharges a descaling agent to the washing water to be supplied into the washing water accommodating unit20.

The descaling agent supply device100may discharge the descaling agent in the form of particles or a liquid, or a solution in which the descaling agent is dissolved in accordance with exemplary embodiments. The descaling agent is discharged in a state of being dissolved in the washing water, and hereinafter, the descaling agent is defined as a material that bonds with metal ions (e.g., Ca2+, Mg2+) in hard water and inhibits formations of scale or removes formed scale, and a solution in which the descaling agent is dissolved is defined as a descaling solution.

The descaling agent includes acid compositions, for example, chemicals such as organic acid including hydrochloric acid, citric acid, malic acid, tartaric acid, acetic acid, lactic acid, and formic acid, phosphoric acid, and sulfamic acid which react with alkaline carbonate and the like in the scale. The chemicals in a liquid phase as well as in a solid phase such as powder or particles may be accommodated in a descaling device. Particularly, the organic acid such as the citric acid is an environmentally-friendly material harmless to humans.

Particularly, the organic acid has an ability to bond with metal ions (e.g., Ca2+, Mg2+) in hard water so as to inhibit formation of scale or remove formed scale. Therefore, by supplying the organic acid through the descaling agent supply device100at an appropriate point of time, it is possible to prevent components, which are often in contact with washing water, such as, for example, a washing water accommodating unit20,20b, or20c, (seeFIGS. 3, 5, 6, and 21), and a washing space20aor22(seeFIGS. 5 and 21), which accommodates the object to be washed, from being contaminated by scale.

The descaling agent supply device100may input one or more kinds of organic acid selected from a group consisting of citric acid, malic acid, tartaric acid, acetic acid, lactic acid, and formic acid. The organic acid is not only known as a material harmless to humans, but also proven to have a descaling effect even though a tiny amount of organic acid is used.

The descaling agent supply device100may include a solution accommodating unit which accommodates the descaling agent such as the organic acid, and a solution discharge valve which adjusts the amount of descaling solution discharged from the solution accommodating unit. Hereinafter, the solution discharge valve may be opened and closed by being controlled by a controller11, illustrated inFIG. 2. The solution discharge valve may be configured as a solenoid valve.

Meanwhile, in a case in which the descaling agent includes organic acid, the organic acid may be input in the form of a liquid, considering that the organic acid has an excellent descaling ability even though a tiny amount of organic acid is used, it is advantageous to input the organic acid in a state of being dissolved in advance in order to uniformly distribute the organic acid in the washing water, and the organic acid needs to be easily and quantitatively input.

As further illustrated inFIG. 2, the washing machine1may include an input unit12which receives various types of commands from a user, the controller11which controls overall operations of the washing machine1, and/or a hardness sensor13which detects hardness of the washing water.

The input unit12may have various input means such as buttons, dials, and touchpads so as to receive, from the user, commands for setting various types of courses such as a washing course, and a rinsing course, or commands for setting a point of time at which the organic acid is input through the descaling agent supply device100.

The controller11may control the discharge means in accordance with the setting input through the input unit12so that the discharge means is opened at a set point of time at which the organic acid is input.

In accordance with exemplary embodiments, the solution discharge valve may be controlled by the controller11based on hardness of the washing water which is detected by the hardness sensor13. The hardness sensor13may detect hardness of the washing water being supplied from an external water source such as a faucet. In this case, the hardness is detected in a state in which no detergent is input into the washing water. As a value of the hardness detected by the hardness sensor13is increased, the controller11may increase an opening frequency or an opening time of the solution discharge valve.

Characteristics of the hardness of the washing water supplied to the washing machine1are determined according to locations where the washing machine1is installed, and are substantially constant as long as the washing machine1is not installed at other locations or treatment of the input water has not changed. The washing machine1may provide a particular function of setting the amount of descaling agent to be supplied each time the descaling agent is supplied using the input unit12. In this case, in a case in which hardness of the washing water at the location where the washing machine1is installed is detected when the washing machine1is installed, and the amount of descaling agent to be supplied is set based on the detected value of hardness by using the input unit12, it is not necessary to substantially change the amount of descaling agent to be supplied except for a special situation such as movement of the washing machine1.

The setting of the amount of descaling agent to be supplied using the input unit12may be carried out in advance by a manufacturer in consideration of characteristics of the location where the washing machine1is sold before the product is shipped.

The input of the descaling agent through the descaling agent supply device100may be carried out each cycle of the washing machine1. A typical fully automatic washing machine automatically performs a series of processes such as a washing process, a rinsing process, a drying process, and a spin-drying process in accordance with the setting of the input unit12. In a case in which the series of processes constitute a single cycle, the controller11may control the solution discharge valve so that the solution discharge valve is opened each cycle.

Otherwise, the input of the descaling agent through the descaling agent supply device100may be carried out based on the number of cycles performed. The washing machine1may include a counter that counts the number of cycles performed. When the number of cycles performed counted by the counter reaches a predetermined number, the controller11may control the solution discharge valve so that the solution discharge valve is opened while the cycle of which the number of cycles performed reaches the predetermined number is carried out. After the descaling agent is supplied by the descaling agent supply device100, the counter is initialized, the number of cycles performed is counted again, and the organic acid is repeatedly input each time the number of cycles performed reaches the predetermined number.

In another manner, the input of the descaling agent through the descaling agent supply device100may be carried out when a predetermined course is input through the input unit12. The input unit12may provide a predetermined course (hereinafter, referred to as a descaling course) in which the descaling agent is supplied to remove or inhibit scale. When the descaling course is selected, the controller11may control the solution discharge valve so that the solution discharge valve is opened while the descaling course is carried out. The predetermined course may be provided separately from the washing course or the rinsing course.

Meanwhile, a single cycle may include a series of processes including a prewashing process, a main washing process, a rinsing process, and/or a heating and rinsing process. The controller11may control the solution discharge valve130so that the solution discharge valve130is opened while the processes are carried out. In this case, the opening time of the solution discharge valve may be controlled differently in accordance with the process that is being carried out.

In several exemplary embodiments as described above, the supply of the descaling agent through the descaling agent supply device100may be quantitatively controlled so that a constant amount of descaling agent is input each time the descaling agent is needed, and to this end, the controller11may control the opening time of the solution discharge valve based on a predetermined time.

Hereinafter, an example of the descaling agent supply device100, which may quantitatively input the descaling agent, will be described with reference toFIG. 3.

FIG. 3illustrates the washing water accommodating unit20which accommodates the washing water, and the descaling agent supply device100which inputs the descaling solution into the washing water accommodating unit20. The descaling agent supply device100includes a solution accommodating unit111which accommodates a descaling agent d, a main flow path112which guides the washing water to the washing water accommodating unit20during a process of supplying the washing water so that the washing water bypasses the solution accommodating unit111, and a branch flow path123which branches off from the main flow path112, and guides the washing water, which is guided along the main flow path112, to the solution accommodating unit111. A water supply valve150may be provided to control supplying of washing water along the main flow path112.

The main flow path112may be divided into an upstream side main flow path112apositioned at an upstream side and a downstream side main flow path112bpositioned at a downstream side, based on a portion where the main flow path112is connected with an inlet of the branch flow path123.

The descaling agent in the form of powder or particles may be input into the solution accommodating unit111. Hereinafter, for example, the descaling agent is an organic acid.

In the solution accommodating unit111, the overall amount of organic acid is not dissolved in the washing water, but only a part of the organic acid is dissolved, and the remaining part of the organic acid is present in a precipitated state. That is, the washing water in the solution accommodating unit111is maintained in a saturated or supersaturated state for a sufficient time until the organic acid is consumed and the washing water becomes an unsaturated state.

The number of times at which the solution discharge valve130is opened to supply the organic acid may be set so that the organic acid may be input roughly 4,000 to 5,000 times until the washing water in the solution accommodating unit111becomes an unsaturated state.

The solution accommodating unit111has a solution outlet111hthrough which an organic acid solution produced in the solution accommodating unit111is discharged, and the solution discharge valve130opens and closes the solution outlet111h. The solution outlet111his maintained in a closed state by the solution discharge valve130during the process of supplying the washing water.

The main flow path112communicates with the washing water accommodating unit20through a washing water outlet path112hand supplies washing water to the washing water accommodating unit20therethrough.

The branch flow path123includes an atmosphere communicating port123dwhich is positioned above the solution outlet111hand communicates with the atmosphere. The atmosphere communicating port123dmay communicate with the atmosphere even while the washing water is supplied into the solution accommodating unit111. Because atmospheric pressure is applied through the atmosphere communicating port123d, the water head is constantly maintained at a downstream side123bof the atmosphere communicating port123don the branch flow path123even though the supply of the washing water is shut off in a state in which the solution accommodating unit111is filled with the washing water. Particularly, because the supply of the washing water into the washing water accommodating unit20is carried out in a state in which the solution outlet111his closed, and a substantially constant atmospheric pressure is applied to the atmosphere communicating port123d, the washing water in the branch flow path123maintains a constant head difference with respect to the solution outlet111hwhen the supply of the washing water is shut off. As a result, the organic acid solution may be quantitatively discharged from the solution accommodating unit111when the solution discharge valve130is opened. Particularly, because a water level in the branch flow path123is constantly maintained with respect to the solution outlet111h, the organic acid may be quantitatively discharged through the solution outlet111heven though water supply pressure varies in accordance with characteristics of locations where the washing machine1is used.

Meanwhile, when the solution accommodating unit111is filled with the washing water supplied through the branch flow path123in a state in which the solution outlet111his closed by the solution discharge valve130, the washing water does not flow into the solution accommodating unit111, but is discharged through the atmosphere communicating port123d. Thereafter, when the supply of the washing water is shut off, the amount of washing water exceeding a maximum water level H in the downstream side branch flow path123band the amount of washing water remaining in the upstream side branch flow path123a, of the overall amount of washing water in the branch flow path123, are moved downward by its own weight and flow into the washing water accommodating unit20along the main flow path112.

When the supply of the washing water is shut off in a state in which the solution accommodating unit111is filled with the washing water, the water level H in the downstream side branch flow path123bis constantly set, and the water level maintains a constant head difference ΔH with respect to the solution outlet111h, such that the water level is defined as a head difference maintaining water level H. The water level in the tub20amay be maintained to be the head difference maintaining water level H or lower.

Meanwhile, in the exemplary embodiment, the branch flow path123has the atmosphere communicating port123dformed at the uppermost end of the flow path, and based on the atmosphere communicating port123d, the upstream side branch flow path123aguides the washing water upward, and the downstream side branch flow path123bguides the washing water downward, but the present embodiment is not necessarily limited thereto. The position of the atmosphere communicating port123dmay be changed as necessary within a range in which the water level in the downstream side branch flow path123bmaintains a constant head difference with respect to the solution outlet111h.

FIG. 4is a perspective view illustrating a dishwasher1aas an example of the washing machine according to the present disclosure.FIG. 5is a view illustrating a state in which a door of the dishwasher1ainFIG. 4is opened.FIG. 6is a view illustrating a configuration of the dishwasher1ainFIG. 4.

Referring toFIGS. 4 to 6, the dishwasher1aincludes a washing water accommodating unit20(not shown, but seeFIGS. 1 to 3) which accommodates washing water for washing dishes, and a descaling agent supply device100(not shown, but seeFIGS. 1 to 3) which discharges a descaling agent into the washing water.

In addition, the dishwasher1amay include a tub20awhich provides a space in which the dishes are washed, and a sump20bin which the washing water, which will be supplied into the tub20a, is collected. The washing water in the sump20bundergoes a circulation process in which the washing water is sprayed into the tub20athrough nozzles8a,8b, and8cwhen a washing pump (not illustrated) is operated, the tub20ais then filled with the sprayed washing water, and then the washing water is collected back to the sump20b. Therefore, since the tub20aand the sump20bare filled with the washing water that is used to wash the dishes, the washing water accommodating unit20is defined as including at least one of the tub20aand the sump20b.

As illustrated inFIG. 4, a casing4may include a cabinet2having a dish entrance opening, and a door3for opening and closing the dish entrance opening. A handle3a, a control panel5for controlling an operation of the dishwasher, and a display6for displaying an operating state of the dishwasher may be provided on the door3. The control panel5may be provided with the input unit12.

In the tub20a, as illustrated inFIG. 5, there are provided racks7aand7bon which the dishes are placed, and the nozzles which are supplied with the washing water from the sump20band spray the washing water to the dishes placed on the racks7aand7b. The number of racks7aand7bmay be one or more, and in the present exemplary embodiment, an upper rack7ais shown, and a lower rack7bis below the upper rack7a. In addition, the number of nozzles8a,8b, and8cmay be more than one so that the washing water is sprayed in various directions, and the nozzles8a,8b, and8cmay include an upper nozzle8awhich sprays the washing water downward toward the upper rack7a, an intermediate nozzle8bwhich is between the upper rack7aand the lower rack7band sprays the washing water downward toward the lower rack7b, and a lower nozzle8cwhich is below the lower rack7band sprays the washing water upward. Although not illustrated, guide flow paths, which guide the washing water from the sump20bto the respective nozzles, may be provided corresponding to the configurations of the nozzles, and a flow path switching unit (not illustrated), which selectively intermits the guide flow paths, may be further provided. There may be further provided a washing pump (not illustrated) which pumps the washing water collected in the sump20bto the guide flow path, and a heater (not illustrated) which heats the washing water in the sump20b.

Referring toFIG. 6, the dishwasher1amay include a water supply device30which supplies washing water to the sump20b. The water supply device30may be between the tub20aand the cabinet2. The water supply device30may include flow paths which guide a flow of the washing water, water chambers which receive the washing water guided by the flow paths, a water supply hose connector32awhich is connected with a water supply hose into which raw water (e.g., tap water) flows, a flowmeter33which detects the amount of raw water flowing into the water supply hose connector32a, a water chamber31which stores the washing water flowing therein, and a vent opening (not illustrated) which communicates the flow paths with the atmosphere in order to prevent siphonage in which the raw water consistently flows in even though the water supply is shut off.

As illustrated inFIG. 3, the solution accommodating unit111may be provided independently of the water supply device30, or may be configured as water chambers formed in the water supply device30in accordance with exemplary embodiments. In this case, the water chamber has the solution outlet111h, and the branch flow path123is connected with the water chamber. The descaling agent supply device100may discharge the organic acid to a flow path of washing water which is provided in the water supply device30.

In another exemplary embodiment, a descaling solution discharged from the descaling agent supply device100may be input directly into the tub20awithout passing through the sump20b.

The water supply device30may further include a sump drain connector32cwhich is connected with a sump drain flow path (not illustrated) along which the washing water used to wash the dishes is guided and drained from the sump20b, and a drain pump inlet connector32dwhich is connected with a drain pump inlet flow path (not illustrated) that guides the washing water flowing into the drain pump.

The washing pump may include a washing water guide (not illustrated) which guides the washing water in the sump20bto the nozzles8a,8b, and8c, an impeller which is rotatably provided in the washing water guide, and a washing motor which rotates the impeller.

A water supply valve (not illustrated), which intermits supply of washing water to the sump20b, may be further provided. According to exemplary embodiments, the water supply valve may be configured to intermit discharge of washing water from the water supply device30in a case in which the washing water is supplied to the sump20bfrom the water supply device30, or configured to intermit supply of washing water from an external water source in a case in which the washing water is supplied directly to the sump20bfrom the external water source. Operations of the water supply valve, the washing motor and the like are controlled by the controller11.

The sump20band the tub20aare in communication with each other, such that the washing water sprayed by the nozzles8a,8b, and8cflows back into the sump20bfrom the tub20a. Furthermore, the tub20ais also in communication with a washing water outlet path112hof the descaling solution supply device100through the sump20b, and as a result, water pressure applied in a washing water outlet path112hvaries according to a water level in the tub20a.

In addition, a filter (not illustrated) may be located in the sump20b, and in this case, the washing water, which has been sprayed into the tub20athrough the nozzles8a,8b, and8c, is filtered while passing through the filter, and then flows back into the sump20b.

In addition, the dishwasher1amay include an additive inputting mechanism which inputs a detergent or a rinse into the washing water, and the additive inputting mechanism inputs the detergent for washing dishes or the rinse for rinsing dishes into the tub20aat a predetermined step during a washing process or a rinsing process.

FIG. 7is a perspective view illustrating a descaling solution supply device100aaccording to another exemplary embodiment of the present invention.FIG. 8is a top plan view of the descaling solution supply device100aillustrated inFIG. 7.FIG. 9is a cross-sectional view taken along line A-A ofFIG. 8.FIG. 10is a cross-sectional view taken along line B-B ofFIG. 8.FIG. 11is a cross-sectional view taken along line C-C ofFIG. 8.FIG. 12is a side view illustrating a configuration of a merging path U of the descaling solution supply device100b.FIG. 13is a partial cross-sectional view taken along line D-D ofFIG. 12. Hereinafter, the descaling solution supply device100aaccording to another exemplary embodiment of the present invention will be specifically described with reference to the drawings.

The descaling solution supply device100aincludes a solution accommodating unit111which accommodates a descaling agent, a main flow path112which guides washing water to a sump20bduring a process of supplying the washing water so that the washing water bypasses the solution accommodating unit111, and a branch flow path123which branches off from the main flow path112and guides the washing water, which is guided along the main flow path112, to the solution accommodating unit111.

Illustrated inFIG. 8, the main flow path112may be divided into an upstream side main flow path112apositioned at an upstream side and a downstream side main flow path112bpositioned at a downstream side, based on a portion where the main flow path112is connected with an inlet of the branch flow path123. According to the aforementioned definition, the solution merging path U, which will be described below, is included in the downstream side main flow path112b.

The solution accommodating unit111has a solution outlet111h(shown inFIG. 11) through which the descaling solution produced in the solution accommodating unit111is discharged. A solution discharge valve130may be further provided to open and close the solution outlet111h. The solution outlet111his maintained in a closed state by the solution discharge valve130during the process of supplying the washing water. A supporters117and127(shown inFIG. 7andFIG. 9) for installing the solution discharge valve130may be formed on an accommodating unit main body110. The solution discharge valve130may be a solenoid valve that is operated by being controlled by a controller11.

As illustrated inFIG. 9, the solution accommodating unit111may be divided into a first accommodating unit111aand a second accommodating unit111bby a partition115. The descaling agent is input into the first accommodating unit111a, and the partition115may have a plurality of through holes (not illustrated) so as to allow washing water to flow between the first accommodating unit111aand the second accommodating unit111b. In a case in which a descaling agent in the form of powder or particles is input into the first accommodating unit111a, the solution inside of the solution accommodating unit111is in a saturated or supersaturated state in which the inputted descaling agent is partially dissolved. In this case, the dissolved components of the descaling agent are diffused into the second accommodating unit111bthrough the through holes, but precipitates, which are not dissolved, are inhibited by the partition115from being moved to the second accommodating unit111b. The solution outlet111hmay communicate the second accommodating unit111bwith the main flow path112, and in this case, the descaling agent, which is not dissolved, is prevented from being discharged through the solution outlet111h.

The dishwasher1amay further include a residual quantity detecting sensor (not illustrated) which detects the quantity of residual descaling agents in the solution accommodating unit111. The residual quantity detecting sensor may be configured as a sensor that detects a change in concentration of the descaling solution. The residual quantity detecting sensor may be disposed in the second accommodating unit111b. The dishwasher may include a controller (not illustrated) that controls various types of components such as the solution discharge valve130, the washing pump, and the drain pump. The controller may determine when to supplement the descaling agent based on a value detected by the residual quantity detecting sensor, and may display that it is time to supplement the descaling agent, through an information device such as a display4and/or an alarm (not illustrated), to alert a user.

The branch flow path123includes an atmosphere communicating port123dwhich is positioned above the solution outlet111hand communicates with the atmosphere. The atmosphere communicating port123dmay communicate with the atmosphere even while the washing water is supplied into the solution accommodating unit111. Because atmospheric pressure is applied through the atmosphere communicating port123d, the water head is constantly maintained at a downstream side123bof the atmosphere communicating port123don the branch flow path123even though the supply of washing water is shut off in a state in which the solution accommodating unit111is filled with the washing water. Particularly, because the supply of washing water to the sump20bis carried out in a state in which the solution outlet111his closed, and a substantially constant atmospheric pressure is applied to the atmosphere communicating port121d, the washing water in the branch flow path123maintains a constant head difference with respect to the solution outlet111hwhen the supply of washing water is shut off, and as a result, the descaling solution may be quantitatively discharged from the solution accommodating unit111when the solution discharge valve130is opened. Particularly, because a water level in the branch flow path123is constantly maintained with respect to the solution outlet111h, the descaling solution may be quantitatively discharged through the solution outlet111heven though water supply pressure varies in accordance with characteristics of locations where the dishwasher is used.

The descaling solution supply device100amay include the accommodating unit main body110which constitutes the solution accommodating unit111, and a main body cover120which has a washing water inlet122into which washing water to be supplied into the solution accommodating unit111flows. In order to easily input and supplement the descaling agent, the main body cover120may be separably coupled to the accommodating unit main body110.

Hereinafter, the configuration in which the washing water flows into the washing water inlet122from the water supply device30is described, but the present embodiment is not necessarily limited thereto, and washing water may flow directly into the washing water inlet122from an external water source such as a faucet through a hose.

The accommodating unit main body110includes the main flow path112. The main flow path112communicates with the sump20bthrough a washing water outlet112f(shown inFIG. 7) and supplies washing water to the sump20b. The main flow path112includes a hose connector112ehaving the washing water outlet112f, and a hose (not illustrated), which communicates the sump20bwith the washing water outlet112f, and may be connected to the hose connector112e. The main flow path112is formed so that the washing water bypasses the solution accommodating unit111and reaches the washing water outlet112f.

The branch flow path123is a flow path along which a part of the washing water, which is guided along the main flow path112and separated from the main flow path112, flows, and may be formed by the main body cover120. The accommodating unit main body110is opened at an upper side thereof in order to input or supplement the descaling agent, and the main body cover120covers the opened upper side. The main body cover120includes a cover portion121(shown inFIG. 7) which covers the opened upper side of the accommodating unit main body110. In the present exemplary embodiment, the main flow path112is opened at the upper side thereof, and the opened side is covered by the cover portion121, thereby preventing washing water from overflowing to the outside of the descaling solution supply device100awhile the washing water is guided.

The branch flow path123extends upward from the cover portion121, and may have an atmosphere communicating port123dformed at an upper end thereof. The branch flow path123may include an upstream side branch flow path123apositioned at an upstream side and a downstream side branch flow path123bpositioned at a downstream side, centered on the atmosphere communicating port123d. The upstream side branch flow path123amay be an upward guide flow path that guides upward the washing water flowing in from the main flow path112, and the downstream side branch flow path123bmay be a downward guide flow path that guides downward the washing water discharged from the upstream side branch flow path123a.

As illustrated inFIG. 9, an outlet123oof the upstream side branch flow path123ais separated from an inlet123iof the downstream side branch flow path123b, and an intermediate flow path123c, through which the washing water discharged from the outlet123oof the upstream side branch flow path123apasses in the process of flowing into the inlet123iof the downstream side branch flow path123b, is formed between the outlet123oand the inlet123i. The intermediate flow path123ccommunicates with the atmosphere through the atmosphere communicating port123d. The branch flow path123may communicate with the atmosphere through the atmosphere communicating port123deven while the washing water is supplied to the sump20b. When the solution accommodating unit111is filled with the washing water supplied through the branch flow path123in a state in which the solution outlet111his closed by the solution discharge valve130, the washing water does not flow into the solution accommodating unit111anymore, but flows into the water supply device30through the atmosphere communicating port123d.

Thereafter, when the supply of washing water is shut off, the amount of washing water exceeding a height of the inlet123iand the amount of washing water remaining in the upstream side branch flow path123a, of the overall amount of washing water in the branch flow path123, move downward by its own weight, reversely flow to the main flow path112, and then flow into the sump20bthrough the washing water outlet112f. In the exemplary embodiment, the downstream side branch flow path123bhas the inlet123ipositioned at the uppermost side of the flow path, and as a result, a maximum water level in the downstream side branch flow path123bis restricted to be equal to or lower than a height of the inlet123iwhen the supply of washing water is shut off. That is, when the supply of the washing water is shut off in a state in which the solution accommodating unit111is filled with the washing water, a water level H2in the downstream side branch flow path123bis constantly set, and the water level maintains a constant head difference (H2−H0) with respect to a water level H0at the solution outlet111h, such that the water level is defined as a head difference maintaining water level H2.

In the exemplary embodiment, the branch flow path123has the atmosphere communicating port123dformed at the uppermost end of the flow path, and based on the atmosphere communicating port123d, the upstream side branch flow path123aguides the washing water upward, and the downstream side branch flow path123bguides the washing water downward, but the present invention is not necessarily limited thereto. The position of the atmosphere communicating port123dmay be changed as necessary within a range in which the water level in the downstream side branch flow path123bmaintains a constant head difference with respect to the solution outlet111h.

Referring toFIG. 13, the outlet123oof the upstream side branch flow path123amay have a smaller cross-sectional area than the inlet123iof the downstream side branch flow path123b. In a case in which the area of the outlet123ois equal to or greater than a predetermined proportion of the area of the inlet123i, a flow rate of washing water discharged through the atmosphere communicating port123dis increased. As a result, there is a problem in that washing water cannot be smoothly supplied to the solution accommodating unit111. The area of the outlet123omay be equal to or smaller than 1/10 of the area of the inlet123i.

Meanwhile, the main flow path112may include the solution merging path U (shown inFIG. 12) into which the descaling solution discharged from the solution outlet111hflows. The solution merging path U is a partial section of the main flow path112, and when the washing water passes through the solution merging path U, the washing water flows together with the descaling solution discharged through the solution outlet111h. The solution outlet111hcommunicates with the solution merging path U, and as a result, the descaling solution is collected in the solution merging path U when the solution discharge valve130is opened in a state in which the washing water being guided along the main flow path112stops flowing, that is, in a state in which the solution merging path U is vacant, or the washing water is accommodated but does not flow in the solution merging path U.

The solution merging path U may be configured to accommodate a predetermined amount of washing water even though the supply of washing water is shut off, and to this end, the solution merging path U may include a downward guide flow path112cwhich guides the washing water downward, and an upward guide flow path112dwhich guides upward the washing water guided along the downward guide flow path112c. In the exemplary embodiment, the solution merging path U is formed in a U shape, and the solution outlet111hmay be positioned in the solution merging path U, particularly, at a position where a flow direction is changed in the solution merging path U. In a state in which the supply of washing water is shut off, a water level in the solution merging path U may be determined in accordance with a position of the washing water outlet112f.

A valve mounting port114in which the discharge valve130is mounted is communicated with the solution merging path U.

When the solution discharge valve130is opened in a state in which no washing water is present in the solution merging path U, the descaling solution is naturally discharged to the solution merging path U by water pressure, but when the solution discharge valve130is opened in a state in which washing water is present in the tub20aat a predetermined water level, the washing water may rather reversely flow from the upward guide flow path112dinto the solution accommodating unit111in accordance with a water level of the washing water in the tub20abecause a section, which is defined from the upward guide flow path112dto the tub20avia the sump20b, is filled with the washing water. Therefore, a water level in the tub20aneeds to be lower than the head difference maintaining water level H2at a point of time at which the solution discharge valve130is opened. To this end, an outlet (not illustrated), which discharges washing water to the outside of the tub20a, may be formed in the tub20aat a position lower than the head difference maintaining water level H2so that a water level in the tub20adoes not exceed the head difference maintaining water level H2. According to exemplary embodiments, a water level detecting sensor (not illustrated), which detects a water level in the tub20a, may be provided, and in this case, the controller controls the supply of washing water so that the supply of washing water is shut off depending on the water level detected by the water level detecting sensor, thereby restricting the water level in the tub20ato be below the head difference maintaining water level H2.

Meanwhile, when the supply of washing water is completed, in a case in which the water level H1in the tub20ais equal to the position of the washing water outlet112f, the descaling solution is quantitatively discharged from the solution accommodating unit111to the main flow path112because of a pressure difference (ΔP=ρ·g·(H2−H1)) between water pressure (P1=ρ·g·H2, ρ: density of washing water, g: gravitational acceleration), which is applied by the washing water accommodated in the solution accommodating unit111at the solution outlet111h(reference water level H0), and water pressure, which is applied from the outside of the solution accommodating unit111, that is, water pressure (P2=ρ·g·H1) which is applied because of a water level in the tub20a. Here, there may actually be a difference in density ρ of the washing water between the inside of the solution accommodating unit111and the inside of the upstream side guide flow path112d, but because a very small amount of descaling agent is dissolved in the washing water, an influence of density is ignored.

FIG. 14is a perspective view illustrating a descaling solution supply device200according to a second exemplary embodiment of the present invention.FIG. 15is a transparent view of the descaling solution supply device200illustrated inFIG. 14.FIG. 16is a view illustrating the inside of an accommodating unit main body210illustrated inFIG. 14.FIG. 17is a top plan view of the descaling solution supply device200illustrated inFIG. 14.FIG. 18is a view illustrating a longitudinal cross section of a branch flow path223.FIG. 19is a partial cross-sectional view taken along line E-E ofFIG. 17.FIG. 20is a cross-sectional view taken along line F-F ofFIG. 17.

Referring toFIGS. 14 to 20, the descaling solution supply device200according to the second exemplary embodiment of the present invention includes an accommodating unit main body210, and a main body cover220, and a solution discharge valve230.

The accommodating unit main body210includes a solution accommodating unit211which accommodates a descaling solution, and a main flow path212which guides washing water during a process of supplying the washing water so that the washing water bypasses the solution accommodating unit211and is guided to a washing water outlet that communicates with a sump20b. The washing water outlet may be formed in a hose connector212fto which a hose (not illustrated) communicated with the sump20bis connected. The main flow path212comprises a flow path212econnecting the connector212fwith the upward guide flow path212d.

At least one partition215, which divides the solution accommodating unit211into two or more spaces, may be provided. In the exemplary embodiment, the solution accommodating unit211is divided, by two partitions215, into a first accommodating unit211a, a second accommodating unit211b, a third accommodating unit211c, and a descaling agent in the form of powder or particles is input into the first accommodating unit211a, and the second accommodating unit211bcommunicates with the main flow path212through a solution outlet211h.

The partition215may have a plurality of through holes215hso as to allow washing water to flow between the accommodating units. In the exemplary embodiment, the through hole215his formed in a slit shape, but the shape of the through hole215hmay of course be changed as appropriate.

A residual quantity detecting sensor (not illustrated), which detects the quantity of residual descaling agents, may be disposed in at least one of the second accommodating unit212band the third accommodating unit212c. Like the aforementioned first exemplary embodiment, the controller may determine when to supplement the descaling agent based on a value detected by the residual quantity detecting sensor, and may display that it is time to supplement the descaling agent, through a display4or an alarm (not illustrated), so as for a user to recognize the time.

A branch flow path223is a flow path along which a part of the washing water, which is guided along the main flow path212and separated from the main flow path212, flows, and may be formed by the main body cover220. The main body cover220covers an opened upper side of the accommodating unit main body210. The main body cover220may include a cover portion221having a descaling agent input opening226, and the branch flow path223may extend upward from the cover portion221. An atmosphere communicating port223dmay be formed at an upper end of the branch flow path223. The branch flow path223may include an upstream side branch flow path223apositioned at an upstream side and a downstream side branch flow path223bpositioned at a downstream side (shown in inFIG. 18), based on the atmosphere communicating port223d. The upstream side branch flow path223amay be an upward guide flow path that guides upward the washing water flowing in from the main flow path212, and the downstream side branch flow path223bmay be a downward guide flow path that guides downward the washing water discharged from the upstream side branch flow path223a.

As shown inFIG. 14, an input opening stopper240, which opens and closes the descaling agent input opening226, may be further provided. It is possible to supplement the descaling agent by opening the stopper240without separating the main body cover220from the accommodating unit main body210.

An outlet223o(not shown) of the upstream side branch flow path223ais separated from an inlet223i(not shown) of the downstream side branch flow path223b, and an intermediate flow path223c(shown inFIG. 18), through which the washing water discharged from the outlet223oof the upstream side branch flow path223apasses in the process of flowing into the inlet223iof the downstream side branch flow path223b, is formed between the outlet223oand the inlet223i. The intermediate flow path223ccommunicates with the atmosphere through the atmosphere communicating port223d. Like the aforementioned exemplary embodiment, the outlet223oof the upstream side branch flow path223amay have a smaller area than the inlet223iof the downstream side branch flow path223b.

The branch flow path223may communicate with the atmosphere through the atmosphere communicating port223deven while the washing water is supplied to the sump20b. When the washing water flows through the branch flow path223and then the solution accommodating unit211is filled with the washing water in a state in which the solution outlet211h(shown inFIG. 20) is closed by a solution discharge valve230, the washing water does not flow into the solution accommodating unit211anymore, but flows into the water supply device30(fromFIG. 6) through the atmosphere communicating port223d.

The main flow path212may include a solution merging path U into which the descaling solution discharged from the solution outlet211hflows. The solution merging path U is a partial section of the main flow path212, and when the washing water passes through the solution merging path U, the washing water flows together with the descaling solution discharged through the solution outlet211h. The solution outlet211hcommunicates with the solution merging path U, and as a result, the descaling solution is collected in the solution merging path U when the solution discharge valve130is opened in a state in which the washing water being guided along the main flow path212stops flowing, that is, in a state in which the solution merging path U is vacant, or the washing water is accommodated but does not flow in the solution merging path U.

The solution merging path U may be configured to accommodate a predetermined amount of washing water even though the supply of washing water is shut off, and to this end, the solution merging path U may include a downward guide flow path212cwhich guides the washing water downward, and an upward guide flow path212dwhich guides upward the washing water guided along the downward guide flow path212c. In the exemplary embodiment, the solution merging path U is formed in a U shape, and the solution outlet211hcommunicates with a portion of the solution merging path U where a flow direction is changed. InFIG. 20, H3indicates a water level of washing water that remains in the solution merging path U in a state in which the supply of washing water is shut off.

The main flow path212may be divided into an upstream side main flow path212apositioned at an upstream side and a downstream side main flow path212bpositioned at a downstream side, based on a portion where the main flow path212communicates with an inlet of the branch flow path223. According to the aforementioned definition, the solution merging path U is included in the downstream side main flow path212b.

The accommodating unit main body210includes an inlet port222through which washing water is introduced. The inlet port222may be communicated with an outlet of the water supply device30or connected a hose which directly supplies washing water from an external water source (e.g. water tap)

A water level in the tub20aneeds to be lower than the head difference maintaining water level H2at a point of time at which the solution discharge valve230is opened. To this end, an outlet (not illustrated), which discharges washing water to the outside of the tub20a, may be formed in the tub20aat a position lower than the head difference maintaining water level H2so that a water level in the tub20adoes not exceed the head difference maintaining water level H2. Like the aforementioned exemplary embodiments, a water level detecting sensor (not illustrated), which detects a water level in the tub20a, may be provided, and in this case, the controller controls the supply of washing water so that the supply of washing water is shut off depending on the water level detected by the water level detecting sensor, thereby restricting the water level in the tub20ato be below the head difference maintaining water level H2.

A first connector224and a second connector225, which are connected with unnecessary washing water outlets provided in the water supply device30, may be provided on the main body cover220for the purpose of shared use of components. A single flow in which washing water flows into any one of the first connector224and the second connector225and is discharged from the other is formed. A space216, which has no opened portion except for the first connector224and the second connector225, is formed in the accommodating unit main body210.

According to exemplary embodiments, the water supply device30may further include a water softener connector (not illustrated) which is connected with a water softener so that washing water flows into the water softener, and a regenerator connector (not illustrated) which is connected with a regenerator so that washing water flows into the regenerator that regenerates the water softener. However, in a case in which the descaling solution supply device200is provided as described in the present exemplary embodiment, a separate water softener is not required, and as a result, the water softener connector and the regenerator connector are also not required. Therefore, the water softener connector is connected with the first connector224, and the regenerator connector is connected with the second connector225, so that washing water, which is discharged from the water chamber of the water supply device30through the water softener connector, sequentially passes through the first connector224and the second connector225, and then flows back into the water chamber through the regenerator connector. The water supply device having the water softener connector and the regenerator connector may be utilized without changing a structure thereof, thereby improving shared use of components.

A process of supplying a descaling solution in the dishwasher according to the aforementioned exemplary embodiments will be described below.

In a state in which the solution outlet111hor211his closed by the solution discharge valve230, washing water is supplied through the water supply device30. The washing water flowing along the main flow path112or212is supplied to the sump20bthrough the hose connected with the hose connector112eor212f, pumped by the washing pump, and sprayed into the tub20athrough the nozzles8a,8b, and8c. The water supply valve (not illustrated), which intermits the supply of washing water, may be provided in accordance with exemplary embodiments, and operations of the water supply valve, the washing pump and the like are controlled by the controller.

When a predetermined condition is satisfied, that is, when a water level in the tub20a, which is detected by the water level detecting sensor, reaches a predetermined water level or when the amount of the supplied washing water detected by the flowmeter33reaches a predetermined amount, the controller controls the water supply valve so that the water supply valve is closed.

Thereafter, the controller opens the solution discharge valve130or230at a predetermined point of time so that the descaling solution is discharged from the solution accommodating unit111or211to the solution merging path U, and thereafter, the controller opens the water supply valve again so that the washing water is additionally supplied to the sump20bvia the solution merging path U. Here, in order to quantitatively supply the descaling solution, the operation of opening the solution discharge valve130or230may be controlled based on time. That is, the time at which the solution discharge valve130or230is opened is constantly controlled, such that the amount of descaling solution, which is supplied through the descaling solution supply device100aor200, may be constantly controlled all the time.

Meanwhile, the dishwasher according to the aforementioned exemplary embodiments may further include a sterilizing device (not illustrated) that sterilizes the washing water accommodated in the solution accommodating unit111or211. The sterilizing device may be a device that discharges antimicrobial materials into washing water, or may include a UV lamp that emits ultraviolet rays into washing water.

FIG. 21is a view illustrating a laundry machine1bas an example of the washing machine according to the present invention. Referring toFIG. 21, the laundry machine1bmay include a casing10, a tub20cwhich is in the casing10and accommodates washing water for washing laundry, a drum22which is disposed in tub20cand into which laundry is inserted, and a descaling agent supply device which discharges organic acid into the washing water. The descaling agent supply device may be any one of descaling agent supply devices100,100a, and200according to the aforementioned exemplary embodiments.

In addition, the laundry machine1bmay include a drive unit35which rotates the drum22, a water supply valve25which intermits supply of washing water from an external water source, and a tub drain hose53through which washing water is discharged from the tub20c. In the present exemplary embodiment, the washing water accommodating unit20(seeFIGS. 1 to 3) includes the tub20c.

The casing10may include a cabinet2awhich defines an external appearance of the laundry machine1band is opened at front and upper sides, a front cover17which is coupled at a front side of the cabinet2aand has a laundry entrance so as to put laundry into and take laundry out of the laundry machine, a control panel5awhich is provided at an upper side of the front cover17and provides a user interface, and a top cover19which is provided at an upper side of the cabinet2a.

An input unit12(seeFIG. 2), which receives various type of control commands from a user, may be provided in the control panel5a. Various programmed courses may be selected by using the input unit12. A controller11(seeFIG. 2) may control overall operations of the laundry machine1b, and may control operations of several components such as the drive unit35and the water supply valve25in accordance with the setting inputted through the input unit12.

A gasket37is provided between the casing10and the tub20c. The gasket37has a front end coupled to the casing10, and a rear end coupled along a circumference of an opened front side of the tub20c. Thereby, the washing water accommodated in the tub20cis prevented from leaking between the tub20cand the casing10. In addition, the gasket37is made of flexible rubber or synthetic resin, and a circumference of the gasket37is folded to have pleats, thereby absorbing vibration in the tub20c.

A door15for opening and closing the laundry entrance is rotatably provided on the front cover17. The control panel5amay be provided with a display unit (not illustrated) which displays various items of information on state of the laundry machine1b, and the input unit12which receives, from the user, various types of control commands about washing courses, operating time for each process, reservation and the like.

The laundry machine1bmay include a detergent box (not illustrated) which accommodates additives such as detergents, fabric softener or bleach, and a detergent box housing34in which the detergent box is detachably accommodated. The detergent box may be provided to be withdrawn through the front side of the front cover17. The detergent box housing34communicates with the tub20c, and when the washing water is supplied, the detergent in the detergent box is mixed with the washing water, and then flows into the tub20cthrough the detergent box housing34.

The tub20cis suspended from the top cover19by a spring24and supported by a damper26. Therefore, vibration in the tub20cis absorbed by the spring24and the damper26. The drum22is rotated by the drive unit35, and a lifter29, which lifts up laundry when the drum22is rotated, is provided in the drum22.

One or more water supply valves25are provided to intermit the supply of washing water into the tub20c. One or more water supply hoses27, which are connected to an external water source such as a faucet and supply washing water, may be provided, and the water supply valves25may intermittently control the water supply hoses27. In addition, a distributor (not illustrated), which distributes the washing water supplied through the water supply hose27to the detergent box, may be further provided. Additives such as the detergent for washing laundry, a rinse for rinsing laundry, and bleach may be dividedly accommodated in the detergent box without being mixed with each other, and washing water is supplied into the respective divided accommodating spaces at a predetermined point of time through the distributor under the control of the controller11, such that the additives may be supplied into the tub20c.

If a route, along which the washing water flowing in through the water supply hose27flows until the washing water is supplied to the tub20c, is defined as a water supply flow path, the descaling agent supply device100,100a, or200may be configured to input a descaling agent, that is, organic acid into the water supply flow path. In this case, the controller11may control the solution discharge valve55,130, or230so that the descaling agent may be input while the washing water is supplied through the water supply flow path.

The present invention is not limited thereto, and the descaling agent supply device100,100a, or200may input the organic acid directly into the tub20cor the drum22in accordance with exemplary embodiments. In this case, the descaling agent supply device100,100a, or200may have an organic acid outlet, which communicates with the tub20cor the drum22, independently of the water supply flow path.

In addition, the laundry machine1bmay further include a drain bellows51which communicates with the tub20c, and a drain pump60which pumps washing water flowing in through the drain bellows51to a drain hose53.

The washing machine according to the present invention may quantitatively supply the descaling solution. Particularly, the supply of descaling solution may be constantly carried out without being affected by deviation of water supply or water supply pressure, and as a result, a required amount of descaling solution may be supplied.

In addition, the washing machine according to the present invention is very convenient because the descaling solution is automatically supplied, and the washing machine supplies a required amount of descaling solution, thereby minimizing the amount of descaling agent to be consumed, and preventing deterioration in durability of products caused by supplying an excessive amount of descaling agent.

The washing machine according to the present invention may use citric acid, malic acid, tartaric acid, acetic acid, lactic acid, formic acid, and the like as the descaling agent, and these materials are very effective in descaling, harmless to humans even if these materials remain on the object to be washed, and environmentally-friendly.

In addition, the washing machine according to the present invention is equipped with a device that automatically inputs the descaling agent, thereby avoiding the user's laborious task of manually and often cleaning the washing machine, and always keeping the washing machine clean.