Apparatus and method for eliminating wrinkles in clothes

Apparatus and method for eliminating wrinkles in clothes in a washing or drying machine using steam to eliminate the wrinkles in clothes, in a state in which the clothes are worn by a user or stored, as well as in a state in which washing of the clothes is terminated. The method includes determining whether or not a wrinkle-eliminating course is selected; supplying hot air to the clothes to eliminate dust from the clothes when it is determined that the wrinkle-eliminating course is selected; and supplying steam to the clothes, from which the dust was eliminated, to eliminate the wrinkles in the clothes.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 2004-100610, filed Dec. 2, 2004, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus and a method for eliminating wrinkles in clothes in a washing or a drying machine having a steam generating device, and more particularly, to an apparatus and a method for eliminating wrinkles in clothes by generating steam to the inside of a washing or a drying machine.

2. Description of the Related Art

Generally, a drying machine is an apparatus for drying wet clothes by rotating a drum containing the clothes (laundry) at a low speed and supplying hot air, obtained by heating and using a heater, to the inside of the drum. Recently, a washing machine having a drying device for performing a drying function (generally, a drum washing machine) is being sold on the market.

Korean Patent Registration No. 10-0435241 discloses a washing machine having a drying device.

When the washing machine, disclosed by the above Patent, performs a drying operation after a dehydrating operation, a drying fan (a blower) generates and sprays compressed air under the condition that a heater is driven to heat an inner space of a chamber.

The sprayed compressed air passes thorough the inner space of the chamber and is converted into hot air, and the hot air is supplied to clothes in a drum to dry the clothes.

The above conventional washing machine removes moisture from the clothes using air of a high temperature heated by the heater under the condition that the dehydrated clothes are placed in the drum, thereby causing the clothes, which have become tangled in the dehydrating operation, to be dried, thus generating wrinkles in the clothes.

In order to solve the above problem, Korean Utility Model Registration No. 0128148 discloses a method for minimizing wrinkles in clothes by supplying steam having a designated moisture content to the dried clothes.

A washing machine, disclosed by the above Utility Model, supplies steam to the clothes, which were dried while in a tangled state, so that the clothes have a designated moisture content. Accordingly, when the clothes are shaken and spread, and are hung out for a designated time, the moisture of the clothes naturally evaporates and the clothes are smoothed out so that the wrinkles in the clothes are minimized. Further, when the clothes are ironed to eliminate the wrinkles, additional moisture is not required, thereby shortening the ironing time. However, since the wrinkles still remain in the clothes, the above method is disadvantageous in that a user must iron the clothes and a drying time taken to naturally evaporate the moisture of the clothes is long.

A drying machine exclusively having a drying function has the above problems, also.

Further, in the case that the steam is supplied to the clothes in a low-temperature state in winter, when the steam at a high temperature is sprayed, a door made of glass may become frozen and crack. When the steam is sprayed to the insides of a duct and a drum at a low temperature, the steam is converted into water and the water falls in the inside of the duct and the drum, or if the steam is sprayed, the steam is condensed on the surface of the glass door at a low temperature and water passes along the surface of the glass door. That is, it is difficult to efficiently spray steam.

Further, in order to reduce the wrinkles in clothes, a method for forming an algorithm for setting courses and functions for forcibly terminating a drying operation when the drying operation at a temperature for a time predetermined according to materials of the clothes is in progress so that ironing is easily performed is suggested. However, the above method eliminates the wrinkles in the clothes only by washing or ironing, but does not have a function for eliminating the wrinkle in the clothes generated when the clothes are put on by a user or stored.

SUMMARY OF THE INVENTION

Therefore, one aspect of the invention is to provide an apparatus and method for eliminating wrinkles in clothes, in which wrinkles in clothes, in a state in which the clothes are worn by a user or stored as well as in a state in which washing of the clothes is terminated by a separate wrinkle-eliminating course using steam, are eliminated.

A further aspect of the invention is to provide an apparatus and method for eliminating wrinkles in clothes, in which steam at a high temperature is sprayed directly to less contaminated clothes necessary to be smoothed down rather than to be washed, thereby effectively eliminating the wrinkles in the clothes without washing, and sterilizing the clothes.

Another aspect of the invention is to provide an apparatus and method for eliminating wrinkles in clothes, in which hot air is supplied to clothes, to which steam was sprayed, thereby efficiently eliminating the wrinkles in the clothes without ironing, and not requiring any additional drying operation.

Yet another aspect of the invention is to provide an apparatus and method for eliminating wrinkles in clothes, in which hot air is supplied to the clothes prior to steam being sprayed to the clothes, thereby eliminating dust or contaminants from the clothes, preventing a door from being frozen and cracking in winter due to the sprayed steam, and inducing the steam to be smoothly sprayed.

In accordance with one aspect, the present invention provides a method for eliminating wrinkles in clothes comprising: determining whether or not a wrinkle-eliminating course is selected; and supplying steam to the clothes and supplying hot air to the clothes, to which the steam was supplied, to eliminate the wrinkles in the clothes, when it is determined that the wrinkle-eliminating course is selected.

Preferably, but not necessarily, the wrinkle-eliminating course may be an independent course for only eliminating the wrinkles in the clothes.

Further, preferably, but not necessarily, a dried state of the clothes may be sensed when the hot air is supplied to the clothes, and the supply of the hot air may be stopped when the drying of the clothes is completed.

Moreover, preferably, but not necessarily, the steam may be supplied to the clothes for a predetermined time; and the hot air may be supplied for another predetermined time, or according to the dried state of the clothes.

Preferably, but not necessarily, hot air obtained by pre-heating may be supplied to the clothes before the steam is supplied to the clothes so as to eliminate dust from the clothes.

In accordance with another aspect, the present invention provides a method for eliminating wrinkles in clothes comprising: determining whether or not a wrinkle-eliminating course is selected; supplying hot air to the clothes to eliminate dust from the clothes when it is determined that the wrinkle-eliminating course is selected; and supplying steam to the clothes, from which the dust was eliminated, to eliminate the wrinkles in the clothes.

In accordance with another aspect, the present invention provides an apparatus for eliminating wrinkles in clothes, contained in a drum, comprising: a signal input unit for selecting a wrinkle-eliminating course; a steam generating device for supplying steam to the inside of the drum; a drying device for supplying hot air to the inside of the drum, to which the steam was supplied; and a control unit for controlling the steam generating device to eliminate the wrinkles in the clothes when the wrinkle-eliminating course is selected.

Preferably, but not necessarily, the wrinkle-eliminating course may be an independent course for only eliminating the wrinkles in the clothes or an operational course for eliminating the wrinkles in the clothes after an operation is completed.

Further, preferably, but not necessarily, the drum may be rotated at a predetermined rpm and a predetermined operation ratio when the steam and the hot air are supplied to the inside of the drum.

Moreover, preferably, but not necessarily, the control unit may operate the steam generating device for a predetermined time to control the steam generating device.

Preferably, but not necessarily, the control unit may sense a dried state of the clothes when the hot air is supplied to the inside of the drum, and cut off the supply of the hot air by stopping the operation of the drying device when the drying of the clothes is completed.

Further, preferably, but not necessarily, the control unit may control the supply of the hot air by operating the drying device at a predetermined temperature for a predetermined time or according to the dried state of the clothes.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Reference will now be made in detail to the embodiments of the present invention, an example of which is illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below to explain the present invention by referring to the annexed drawings.

FIG. 1is a sectional view of a washing machine having a steam generating device in accordance with a first embodiment of the present invention.

InFIG. 1, the washing machine having the steam generating device in accordance with the first embodiment of the present invention comprises a drum-shaped tub11installed in a main body10for containing washing water, and a rotary drum12rotatably installed in the tub11and provided with a plurality of dehydration holes.

A motor13for rotating the rotary drum12in a designated regular direction or its reverse direction to performing washing, rinsing, and dehydrating operations is installed under the tub11, and a washing heater19for heating the washing water, supplied to the inside of the tub11when a user select a temperature of the washing water, is installed on the bottom of the inside of the tub11.

An opening14for allowing the user to take clothes out of the main body10is formed through the front surfaces of the tub11and the rotary drum12, and a door15for opening and closing the opening14is installed on the front surface of the main body10.

A detergent supply device18for supplying detergent to the inside of the tub11, a steam generating device30for supplying steam to the inside of the tub11, and a water supply device20for supplying water to the tub11and the steam generating device30are installed above the tub11.

The inside of the detergent supply device18is divided into plural spaces, and the detergent supply device18is installed in the front portion of the main body10so that the user easily supplies the detergent and a fabric softener to the respective spaces.

The water supply device20includes a water supply pipe21for supplying the water to the tub11, and a water supply valve22installed in the water supply pipe21for controlling the supply of the water into the water supply pipe21. Here, the water supply pipe21is connected to the detergent supply device18so that the water is supplied from the outside to the detergent supply device18. A separate connection pipe23for supplying the water from the detergent supply device18to the tub11is installed between the detergent supply device18and the tub11. The water, supplied to the inside of the tub11, passes through the detergent supply device18, thereby allowing the detergent in the detergent supply device18to dissolve in the water and then to be supplied to the tub11.

The water supply device20further includes a steam water supply pipe24for supplying the water to the steam generating device30, and a steam valve25installed in the steam water supply pipe24for controlling the supply of the water into the steam generating device30.

Although the water supply valve22and the steam valve25are separately formed in this embodiment, the present invention is not limited thereto. That is, the water supply valve22and the steam valve25may be integrated into a conventional motor-driven three-way or four-way valve.

The steam generating device30includes a U-shaped steam heater31installed therein for temporarily heating water passing therethrough to generate steam at a high temperature of more than 100° C., a temperature sensor32installed on the outer surface of the steam generating device30for sensing the temperature of the steam generating device30, a steam supply pipe33extended from the steam generating device30towards a drying duct42for supplying the generated steam to the drying duct42, a steam generating pipe34provided with an inlet connected to the steam water supply pipe24and an outlet connected to the steam supply pipe33, and a spray nozzle35installed at the outlet of the steam supply pipe33.

Although the steam heater31is installed inside the steam generating device30in this embodiment, the present invention is not limited thereto. That is, the steam heater31may be an external heater contacting the outer surface of the upper or lower portions of the steam generating device30, or may surround the outer surface of the steam generating device30.

The washing machine in accordance with the first embodiment of the present invention further comprises a drying device40for drying clothes (laundry). The drying device40includes a drying fan41installed on the tub11, the drying duct42connecting an outlet41bof the drying fan41and an air inlet45formed through the upper portion of the opening14of the tub11, and a condensing duct43installed in the rear of the tub11for connecting an air outlet46formed through the lower part of the rear surface of the tub11and an inlet41aof the drying fan41.

The drying device40further includes a drying heater44installed in the drying duct42for supplying hot air to the inside of the tub11, a drying sensor47installed in the rotary drum12for sensing a dried state of the clothes, a duct temperature sensor48installed in the drying duct42for sensing the temperature in the drying duct42when hot air is supplied to the tub11, and a condensing device installed in the condensing duct43for condensing moisture to eliminate it when steam having a high humidity generated from the drying of the clothes passes through the condensing duct43.

The above constitution of the drying device40causes air, blown by the operation of the drying fan41, to be heated by the drying heater44and then to be supplied to the inside of the tub11, thereby heating and drying the clothes in the tub11. Further, when the steam having a high humidity generated from the drying of the clothes is inhaled into the drying fan41through the condensing duct43, moisture in the air is eliminated.

The condensing device includes a cooling water spray nozzle53installed at the upper portion of the inside of the condensing duct43for spraying cooling water to the inside of the condensing duct43, and a cooling water supply pipe54connected to the water supply device20for supplying the cooling water to the cooling water spray nozzle53. The above constitution of the condensing device causes the cooling water sprayed from the cooling water spray nozzle53to flow down along the inner surface of the condensing duct43, thereby increasing contact between air having a high humidity ascending and the cooling water, thus improving a dehumidifying effect.

The washing machine in accordance with the first embodiment of the present invention further comprises a drainage device50for discharging water in the tub11. The drainage device50includes a drainage pipe51connected to the lower portion of the tub11for guiding the water of the tub11to the outside, and a drainage pump52installed in the drainage pipe51.

Hereinafter, the operation of the above washing machine having the steam generating device will be described.

When the washing machine is operated under the condition that clothes are put into the rotary drum12and a detergent is supplied to the detergent supply device18, the water supply valve22of the water supply device20is opened so that water is supplied to the detergent supply device18. The detergent in the detergent supply device18dissolves in the washing water, which is supplied to the tub11through the detergent supply device18, and is then supplied to the tub11.

After the supply of the washing water is completed, the washing heater19is operated to heat the washing water filling the tub11. After a designated time elapses so that the washing water is heated to a temperature necessary for washing, the rotary drum12is rotated in a designated regular direction or its reverse direction by the operation of the motor13.

Here, lifters installed on the inner surface of the rotary drum12move the clothes so that the clothes are washed by friction between the clothes and the rotary drum12and the decomposition effect of the detergent.

After the washing is completed, a rinsing operation, in which a dehydration of the clothes and a supply of water to the clothes are repeated, is performed. Water for performing the rinsing operation is supplied to the inside of the tub11through the water supply pipe21by opening the water supply valve22, and the water in the tub11is discharged to the outside through the drainage pipe51by the operation of the drainage pump52.

When a final dehydrating operation is performed after the rinsing operation, the drainage pump52is operated and the rotary drum12is rotated at a high speed for a designated time, thereby dehydrating the clothes.

When a drying operation is performed after the dehydration of the clothes is completed as described above, the rotary drum12is slowly rotated by the operation of the motor13so that the clothes in the rotary drum12are dropped. When the drying fan41is operated in this state, air in the tub11is sucked into the drying fan41through the condensing duct43, and is discharged to the inside of the tub11through the drying duct42. This circulation of the air is repeated.

Here, air in the drying duct42is heated by the drying heater44, and is supplied to the inside of the rotary drum12, and the clothes in the rotary drum12are heated and dried by hot air.

FIG. 2is a sectional view of a drying machine having a steam generating device in accordance with a second embodiment of the present invention.

InFIG. 2, the drying machine having the steam generating device in accordance with the second embodiment of the present invention comprises a drum70having a cylindrical structure installed in a housing60having an approximately hexahedral structure and provided with opened front and rear surfaces. The drum70is supported by a front bracket71and a rear bracket73, which slidably support inner cylindrical surfaces of front and rear ends of the drum70, and slide pads93for facilitating the rotation of the drum70are respectively installed between the drum70and the front bracket71and between the drum70and the rear bracket73.

Air suction holes74for sucking hot air therethrough are formed through the upper portion of the rear bracket73, and an air suction duct75for guiding the hot air to the air suction holes74is installed in the rear of the rear bracket73. The air suction duct75is extended from the lower part of the drum70backwards, and is bent upwards so as to be connected to the air suction holes74. A heater76for heating the air sucked from the inside of the housing60is installed at an inlet of the air suction duct75.

A central portion of the front bracket71is opened so that an object to be dried is put into the housing60from a door61therethrough, and air discharge holes72for discharging air containing moisture evaporated from the object are formed through the lower portion of the front bracket71.

An air discharge duct77for discharging the air, discharged from the air discharge holes72, to the outside of the drying machine, an air blast fan78, and a discharge pipe80are installed below the drum70. The air discharge duct77guides the air, discharged from the air discharge holes72, to the lower portion of the housing60. Here, the air discharge duct77is connected to the air blast fan78generating force for inducing the flow of air in the drying machine.

The air, discharged through the air blast fan78, is discharged to the outside of the drying machine by a discharge pipe80, one end of which is connected to a fan casing79of the air blast fan78and the other end of which is extended to the outside of the housing60.

A driving motor90for simultaneously driving the air blast fan78and the drum70is installed in the lower portion of the housing60. A driving shaft is extended outwardly from both ends of the driving motor90so that one extended end of the driving shaft is connected to the air blast fan78and the other extended end of the driving shaft is connected to a pulley91for driving the drum70. The pulley91is connected to the drum70by a belt94, thereby rotating the drum70by the driving of the driving motor90.

In the same manner as the washing machine as shown inFIG. 1, the steam generating device30of the drying machine is installed above the drum70. Since the steam generating device30of the drying machine has the same constitution as that of the washing machine ofFIG. 1, elements of the steam generating device30of the drying machine, which are substantially the same as those of the steam generating device of the washing machine, are denoted by the same reference numerals, and a detailed description thereof will thus be omitted.

Hereinafter, the operation of the above drying machine having the steam generating device will be described.

When the drying machine is operated under the condition that wet clothes are put into the rotary drum70through the door61, the drum70and the air blast fan78are simultaneously rotated by the operation of the driving motor90.

The rotation of the drum70allows the clothes in the drum70to be uniformly mixed and dried, and air in the drum70is discharged to the outside by the rotation of the air blast fan78through the air discharge duct77and the discharge pipe80.

Here, the air in the housing60is supplied to the drum70having a low pressure due to the air discharged therefrom, and compensates for the lowered pressure of the drum70. The air is supplied to the inside of the drum70through the air suction duct75under the condition that the air is heated by the heater76and is converted into hot air. The hot air evaporates moisture contained in the clothes, thereby drying the clothes.

Since control algorithms for eliminating wrinkles in clothes in the washing and drying machines having the steam generating device30by generating steam are the same, hereinafter, the control algorithm for eliminating wrinkles in clothes in the washing machine having the steam generating device30will be exemplarily described.

FIG. 3is a block diagram of a system for controlling the washing machine having the steam generating device in accordance with the present invention. The system comprises a signal input unit100, a water level sensing unit110, a temperature sensing unit120, a dry sensing unit130, a control unit140, and a driving unit150.

The signal input unit100serves to input operating data, such as a washing course, a washing temperature, a dehydration rpm, and whether or not a rinsing operation is added, which are selected by a user according to the materials of the clothes, to the control unit140. Further, the signal input unit100is used to select one of a single wrinkle-eliminating course using steam and a wrinkle-eliminating course after operation.

The water level sensing unit110serves to sense the level of the washing water supplied to the tub11, and the temperature sensing unit120serves to sense the temperature of the washing water in the tub11, the temperature of the steam generating device30, the internal temperature of the tub11(the temperature of the tub11), and the temperature of hot air supplied to the inside of the tub11. The dry sensing unit130serves to detect the temperature and humidity of the clothes, thereby sensing the dried state of the clothes.

The control unit140is a microcomputer for controlling the washing machine according to the operating data inputted from the signal input unit100, and in the case that the single wrinkle-eliminating course using steam or the wrinkle-eliminating course after operation is selected, controls the driving of the steam generating device30and the drying device40so that hot air is supplied after steam is supplied for a designated time so as to eliminate the wrinkles in the clothes.

The driving unit150drives the motor13, the washing heater19, the water supply valve22, the steam valve25, the steam heater32, the drying fan41, the drying heater44, and the drainage pump52according to a driving control signal of the control unit140.

Hereinafter, the operation and function of a process for eliminating wrinkles in clothes in the above washing or drying machine having the steam generating device will be described.

FIG. 4is a flow chart illustrating a method for eliminating wrinkles in clothes using steam in accordance with the present invention. The above method may be performed during the drying operation, or performed independently from the drying operation. Accordingly, a winkle-eliminating operation may be set to a default value so that the wrinkle-eliminating operation is automatically performed when the drying operation is performed, or a separation option key is provided so that the wrinkle-eliminating operation is performed only when a user presses the option key.

When the user puts clothes (laundry), to eliminate wrinkles thereof, into the rotary drum12and selects a single wrinkle-eliminating course or the other option (a wrinkle-eliminating course after operation), the operating data selected by the user are inputted to the control unit140through the signal input unit100(S100).

Here, the clothes in the rotary drum12may be clothes, which require only the elimination of wrinkles generated when the clothes are put on or stored, or clothes, which had been washed.

When the wrinkle-eliminating course is selected, the control unit140controls the drying device40so that hot air at a predetermined temperature (temperature for smoothly spraying steam: approximately 40˜60) is supplied to the rotary drum12(S200).

Hereinafter, the above preheated hot air supply step will be described in more detail.

The rotary drum12is slowly rotated at a predetermined rpm and a predetermined operation ratio by the operation of the motor13. When the drying fan41is operated under the above state, the air in the tub11is sucked into the drying fan41through the condensing duct43, and is then discharged to the inside of the tub11through the drying duct42. This circulation of the air is repeated.

Here, the air in the drying duct42is heated by the drying heater44and is introduced into the rotary drum12, thereby heating the air and the clothes in the rotary drum12.

Since the internal temperature of the rotary drum12is increased by supplying the hot air to the rotary drum12before steam is sprayed onto the clothes in the rotary drum12, it is possible to prevent the glass door15from being frozen and cracking in winter, to smoothly spray steam due to the increase of the temperatures of the drying duct42and the door15, and to separate dust or contaminants from the clothes by supplying hot air to the clothes.

In the preheated hot air supply step, the predetermined rpm and operation ratio of the rotary drum12are values, which are set by a designer using experimental data, and vary according to volumes or design conditions of a product. If necessary, the rotary drum12is not rotated.

In the preheated hot air supply step, since the internal temperature of the rotary drum12is increased by the hot air supplied to the inside of the rotary drum12through the drying duct42, the internal temperature (DT) of the drying duct42is sensed by the temperature sensing unit120and is outputted to the control unit140(S300).

The control unit140compares the internal temperature (DT) of the drying duct42, inputted from the temperature sensing unit120, to a predetermined temperature (DTS: a temperature for smoothly spraying steam, approximately 40˜60° C.), and determines whether or not the internal temperature (DT) is more than the predetermined temperature (DTS) (S400).

When the internal temperature (DT) is more than or equal to the predetermined temperature (DTS), the control unit140determines that the internal temperature of the rotary drum12is increased enough to smoothly spray the steam, and stops the supply of the preheated hot air.

After the supply of the preheated hot air is completed, the control unit140controls the steam generating device30so that steam is supplied to the inside of the rotary drum12for a predetermined time (S500).

Hereinafter, the above steam supply step will be described in more detail.

The rotary drum12is slowly rotated at a predetermined rpm and a predetermined operation ratio (on/off ratio, for example a ratio of 20 seconds/2 seconds) by the operation of the motor13). In this state, the steam valve25is opened, and water is supplied to the steam generating device30through the steam water supply pipe24. The water, supplied to the steam generating device30, is momentarily heated by the steam heater31, and generates steam of a high temperature of more than 100° C. The steam of the high temperature is supplied to the inside of the tub11through the steam generating pipe33and the drying duct42, thereby being sprayed directly onto the clothes in the tub11.

As described above, in the method for eliminating wrinkles in clothes of the present invention, the steam, which is directly sprayed onto the clothes in the tub11, affects a rearrangement of bridge bonds in fiber to eliminate the wrinkles in the clothes, and has a sterilizing effect of the clothes.

In the steam supply step, the predetermined rpm and operation ratio of the rotary drum12are values, which are set by the designer using experimental data, and vary according to volumes or design conditions of a product. Generally, the predetermined rpm and operation ratio of the rotary drum12in the steam supply step are higher than those of the rotary drum12in the preheated hot air supply step.

Thereafter, the control unit140checks the steam supply time of the steam generating device30, and determines whether or not a designated time (T1: the overall operation time of the steam generating device30from the preheating of the heater) has elapsed (S600). When the designated time (T1) has elapsed, the control unit140stops the operation of the steam generating device30.

After the supply of the steam is completed, the control unit140controls the drying device40so that dried hot air of a predetermined temperature (temperature lower than that of a general drying operation; approximately 70° C.) is supplied to the inside of the rotary drum12for a predetermined time (S700).

Hereinafter, the above dried hot air supply step will be described in more detail.

The rotary drum12is slowly rotated at a predetermined rpm and a predetermined operation ratio by the operation of the motor13so that the clothes are dropped in the rotary drum12. When the drying fan41is operated under the above state, the air in the tub11is sucked into the drying fan41through the condensing duct43, and is then discharged to the inside of the tub11through the drying duct42. This circulation of the air is repeated.

Here, the air in the drying duct42is heated by the drying heater44, and is introduced into the rotary drum12, thereby heating and drying the clothes in the rotary drum12.

As described above, in the method for eliminating wrinkles in clothes of the present invention, the hot air, which is supplied to the clothes after the steam is sprayed onto the clothes, efficiently eliminates wrinkles in the clothes without ironing, and the clothes do not require an additional drying step, thus being simply treated.

In the dried hot air supply step, the predetermined rpm and operation ratio of the rotary drum12vary according to volumes or design conditions of a product. Generally, the predetermined rpm and operation ratio of the rotary drum12in the dried hot air supply step are higher than those of the rotary drum12in the steam supply step.

Thereafter, the control unit140checks the hot air supply time of the drying device40, and determines whether or not a designated time (T2: approximately 15 minutes) has elapsed (S800). When the designated time (T2) has elapsed, the control unit140senses the temperature and humidity of the clothes by the drying sensor47, and determines whether or not the drying of the clothes is completed (S900).

When the drying of the clothes is not completed, the control unit140feeds the method back to the step S700so that the dried hot air is continuously supplied, and when the drying of the clothes is completed, the control unit140stops the operation of the drying device40.

Although the exemplary embodiment of the present invention, the determination whether or not the drying of the clothes is completed according to the temperature and humidity of the clothes is performed after the hot air supply time has elapsed, the determination may be performed before the hot air supply time has elapsed, and thus it is possible to stop the supply of the hot air before the designated time has elapsed.

Now, with reference toFIG. 5, the steam supply step of the method for wrinkles in clothes using the steam shown inFIG. 4will be described in more detail.

In order to supply a large quantity of steam of a high temperature of more than 100° C. to the inside of the tub11, the control unit140preheats the steam heater31installed in the steam generating device30(S510).

The preheating of the steam heater31allows the steam generating device30in an initial operating stage to supply pure steam, which is not mixed with water of a normal temperature (23˜24° C.), to the inside of the tub11.

The temperature (ST) of the steam generating device30heated by the preheating of the steam heater31is sensed by the temperature sensing unit120, and is outputted to the control unit140(S520). The control unit140compares the temperature (ST) of the steam generating device30, inputted from the temperature sensing unit120, to a predetermined reference temperature (STS: the lowest temperature at which the steam heater is heated for generating the steam, approximately 100° C.), and determines whether or not the temperature (ST) of the steam generating device30is more than the predetermined reference temperature (STS) (S530).

As a comparison result, when the temperature (ST) of the steam generating device30is more than or equal to the predetermined reference temperature (STS), the control unit140turns the steam valve25on (S540).

When the steam valve25is turned on, water is supplied to the steam generating device30through the steam water supply pipe24, and the water, supplied to the steam generating device30, is momentarily heated by the steam heater32, thus generating steam of a high temperature of more than 100° C.

The steam of the high temperature is supplied to the inside of the tub11through the steam supply pipe33and the spray nozzle35, thus being sprayed onto clothes, to eliminate wrinkles thereof.

Thereafter, when a predetermined time (T3: time for generating pure steam of a high temperature of more than 100° C., approximately 2 seconds) from the turning on of the steam valve25has elapsed (S550), the control unit140turns the steam valve25off (S560).

When a predetermined time (T4: time for increasing the temperature of the steam generating device to a high temperature of more than 100° C., approximately 10 seconds) from the turning off of the steam valve25has elapsed (S570), the control unit140turns the steam valve25on again. Then, the above procedure is repeated.

Although the exemplary embodiment discloses a drum washing machine having a drying function, the present invention is not limited thereto. That is, the present invention may be applied to any washing or drying machine, which can supply steam and hot air.

As apparent from the above description, the present invention provides an apparatus and method for eliminating wrinkles in clothes in a washing or drying machine having a steam generating device, in which wrinkles in clothes, in a state in which the clothes are worn by a user or stored as well as in a state in which washing of the clothes is terminated by a single wrinkle-eliminating course or a wrinkle-eliminating course after operation, are eliminated.

In the apparatus and method for eliminating wrinkles in clothes, steam at a high temperature is sprayed directly to less contaminated clothes necessary to be smoothed down rather than to be washed, thereby effectively eliminating the wrinkles in the clothes without washing, and sterilizing the clothes.

In the apparatus and method for eliminating wrinkles in clothes, since hot air is supplied to the clothes, to which steam was sprayed, it is possible to efficiently eliminate the wrinkles in the clothes without ironing and to omit any additional drying operation, thereby shortening a drying time and easily treating the clothes.

In the apparatus and method for eliminating wrinkles in clothes, hot air is supplied to the clothes prior to the steam being sprayed to the clothes, thereby eliminating dust or contaminants from the clothes, preventing a door from being frozen and cracking in the winter due to the sprayed steam, and inducing the steam to be smoothly sprayed.