Spray type drum washing machine

A spray type drum washing machine including a tub mounted in a cabinet, and adapted to contain wash water therein, a circulation line connected between a portion of the tub and another portion of the tub to circulate wash water through the tub, a pump installed at the circulation line, and adapted to forcibly feed wash water through the circulation line for the circulation of the wash water through the tub, and an atomizing device provided at the circulation line, and adapted to atomize the wash water fed through the circulation line, whereby the wash water to circulate through the tub is supplied in an atomized state into the tub. The wash water can rapidly permeate clothes contained in the drum, so that it can more effectively come into contact with contaminants attached to the clothes. As a result, it is possible to achieve an enhancement in washing and rinsing performances while reducing the consumption of wash water.

The Non-provisional application claims priority under 35 U.S.C. & 119 (a) on patent application Ser. No. (s) 10-2003-0023320 and 10-2003-0024911 filed in Korea on Apr. 14, 2003 and Apr. 19, 2003, respectively, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a drum washing machine adapted to wash clothes, and more particularly to a spray type drum washing machine capable of atomizing wash water contained in a tub, and spraying the atomized wash water into a drum, thereby achieving an enhancement in washing performance.

2. Description of the Related Art

Drum washing machines are generally adapted to wash laundry contained in a drum, such as clothes or bedding, through wash, rinse, and spin-dry cycles, in order to remove contaminants attached to the laundry in accordance with the action of wash water contained in a tub.

FIG. 1is a partially-broken perspective view illustrating a conventional drum washing machine.FIG. 2is a sectional view illustrating the conventional drum washing machine.

As shown inFIGS. 1 and 2, the conventional drum washing machine includes a base1, and a cabinet2installed on the base1while defining the appearance of the washing machine. The cabinet2is provided with an access opening2afor loading and unloading of clothes m. The conventional drum washing machine also includes a door4hingably mounted to a front wall of the cabinet2, and adapted to open and close the access opening2a, a tub6mounted in the cabinet2while being supported by a damper, a water supply unit10adapted to supply wash water w into the tub6, a drainage unit12adapted to drain the wash water w from the tub2to the outside of the cabinet2, a drum20rotatably mounted in the tub6, and adapted to contain clothes therein, and a drum motor30adapted to rotate the drum20.

The tub6is provided with an access opening7arranged in rear of the access opening2aof the cabinet2to allow the user to put clothes m into the drum20and to take the clothes out of the drum20.

The drum20is also provided with an access opening21arranged in rear of the access opening2aof the cabinet2to allow the user to put clothes m into the drum20and to take the clothes out of the drum20. The drum20is arranged such that a bottom portion thereof is dipped in wash water contained in the tub6. The drum20is also formed with a plurality of water holes22at peripheral and rear walls thereof to allow wash water to flow between the tub6and the drum20.

Lifters26are mounted to an inner peripheral surface of the drum20. The lifters26serve to raise clothes contained in the drum20to the top of the drum20, and then to release the clothes, thereby allowing the clothes to be dropped due to gravity.

The drum motor30is mounted to a rear wall of the tub6at the outside of the tub6. The drum motor30has a rotating shaft32extending horizontally or approximately horizontally through a central portion of the rear wall of the tub6into the drum20. The rotating shaft32is connected to a central portion of a rear wall of the drum20.

InFIG. 1, reference numeral48designates a gasket mounted to the tub6, and adapted to prevent leakage of wash water between the access openings of the door4and tub6in a closed state of the door4.

Operation of the conventional drum washing machine having the above described configuration will now be described.

When the drum washing machine is operated under the condition in which the door4has been closed after clothes m have been put into the drum20, wash water is supplied into the tub6in accordance with operation of the water supply unit10, so that it is contained in a bottom portion of the tub6. In this state, the bottom portion of the drum20is also dipped in the wash water as the wash water is introduced into the drum20through the water holes22. As a result, the clothes in the drum20are wetted by the wash water.

Thereafter, the motor30is driven to rotate the drum20. Thus, the clothes m contained in the drum20are repeatedly raised and dropped in the drum20. As a result, stains are removed from the clothes m in accordance with the frictional action of the wash water and the inner surface of the drum20.

After completion of this wash cycle, the wash water existing in the water tub10in a contaminated state is externally drained from the drum washing machine through the drainage unit12.

Subsequently, the drum washing machine performs, several times, a rinse cycle for rinsing the washed clothes m to remove bubbles remaining on the clothes m. In this rinse cycle, wash water is supplied into the tub6by the water supply unit10. Thereafter, the drum motor30is driven to rotate the drum20, thereby causing the clothes m contained in the drum20to be repeatedly raised and dropped in the drum20. As a result, bubbles are removed from the clothes m.

The contaminated wash water containing the removed bubbles is externally drained from the washing machine through the drainage unit12.

After performing the rinse cycle several times, the washing machine performs a spin-dry cycle to remove moisture form the clothes m.

That is, when the drum motor30rotates the drum20at high speed, moisture permeated into the clothes m is centrifugally removed from the clothes m, and then collected in the tub6after being discharged from the drum20through the water holes22. Finally, the collected moisture is externally drained through the drainage unit12.

In the above mentioned conventional drum washing machine, however, there is a problem in that the clothes put into the drum20are simply naturally wetted by wash water supplied into the drum20or contained in the tub6. That is, detergent supplied into the drum20is insufficiently dissolved in the wash water. Also, the speed, at which wash water permeates the clothes, is low.

Furthermore, although washing of clothes is carried out in the conventional drum washing machine, using wash water contained in the tub6, a part of the wash water contained in the tub6may be insufficiently used in the clothes washing process. In order to obtain sufficient washing performance, it is necessary to use a large amount of wash water.

SUMMARY OF THE INVENTION

Therefore, the present invention has been made in view of the above mentioned problems involved with the related art, and it is an object of the invention to provide a spray type drum washing machine in which wash water contained in a tub is atomized to be sprayed into a drum, thereby being capable of achieving an enhancement in washing and rinsing efficiencies while using a reduced amount of wash water in accordance with circulation of the sprayed wash water.

Another object of the invention is to provide a spray type drum washing machine in which wash water circulating in the drum washing machine is heated to generate steam, and the generated steam is sprayed into the drum, thereby being capable of achieving an enhancement in washing and sterilization performances.

In accordance with one aspect, the present invention provides a spray type drum washing machine comprising: a cabinet; a tub mounted in the cabinet, and adapted to contain wash water therein; a circulation line connected between a portion of the tub and another portion of the tub to circulate wash water through the tub; a pump installed at the circulation line, and adapted to forcibly feed wash water through the circulation line for the circulation of the wash water through the tub; and atomizing means provided at the circulation line, and adapted to atomize the wash water fed through the circulation line, whereby the wash water to circulate through the tub is supplied in an atomized state into the tub.

The atomizing means may comprise a case arranged at the circulation line, and adapted to allow wash water to pass therethrough, diffusion means provided at an inlet portion of the case, and adapted to diffuse wash water to be introduced into the case, thereby atomizing the wash water, and a blowing fan adapted to forcibly feed, into the tub, the atomized wash water emerging from the diffusion means.

The diffusion means may comprise at least one centrifugal plate adapted to be rotated about an axis passing through a center thereof by a driving force, and a diffusion net arranged around the centrifugal plate, and adapted to diffuse wash water radially projected from the centrifugal plate in an atomized state.

The at least one centrifugal plate may comprise a plurality of centrifugal plates axially spaced apart from one another.

The centrifugal plate and the blowing fan may be rotated by a dual-shaft motor adapted to generate the driving force.

The circulation line may be provided, at an outlet end thereof, with a diffusion nozzle.

The spray type drum washing machine may further comprise a steam generating device installed at the circulation line, and adapted to heat the atomized wash water emerging from the atomizing means, thereby changing the atomized wash water into steam, and to supply the steam into the tub.

The steam generating device may comprise a container arranged at the circulation line, and adapted to allow the atomized wash water emerging from the atomizing means to pass therethrough, and a heater adapted to heat the atomized wash water passing through the container.

The steam generating device may further comprise temperature sensing means adapted to measure an internal temperature of the container.

In accordance with another aspect, the present invention provides a spray type drum washing machine comprising: a cabinet; a tub mounted in the cabinet, and adapted to contain wash water therein; a circulation line connected between a portion of the tub and another portion of the tub to circulate wash water through the tub; a pump installed at the circulation line, and adapted to forcibly feed wash water through the circulation line for the circulation of the wash water through the tub; atomizing means provided at the circulation line, and adapted to atomize the wash water to circulate through the tub; and steam generating means installed at the circulation line, and adapted to heat the atomized wash water emerging from the atomizing means, thereby changing the atomized wash water into steam, and to supply the steam into the tub.

In accordance with still another aspect, the present invention provides a spray type drum washing machine comprising: a cabinet; a tub mounted in the cabinet while carrying a drum therein, and adapted to contain wash water therein; a circulation line connected between bottom and top portions of the tub to circulate wash water through the tub; a pump installed at the circulation line, and adapted to forcibly feed wash water through the circulation line for the circulation of the wash water through the tub; atomizing means provided at the circulation line downstream from of the pump, and adapted to atomize the wash water to circulate through the tub; and a diffusion nozzle provided at an outlet end of the circulation line, and adapted to spray, into the tub, the wash water atomized while passing through the atomizing means.

The atomizing means may comprise a case arranged at the circulation line, and adapted to allow wash water to pass therethrough, at least one centrifugal plate arranged in the case, and adapted to centrifugally radially project the wash water introduced into the case, a diffusion net arranged around the centrifugal plate, and adapted to atomize the wash water centrifugally radially projected from the centrifugal plate when the wash water passes therethrough, a blowing fan adapted to forcibly feed, into the tub, the atomized wash water emerging from the diffusion net, and drive means adapted to rotate the centrifugal plate and the blowing fan.

The spray type drum washing machine may further comprise steam generating means installed at the circulation line, and adapted to heat the atomized wash water emerging from the atomizing means, thereby changing the atomized wash water into steam, and to supply the steam into the tub.

The steam generating device may comprise a container arranged at the circulation line, and adapted to allow the atomized wash water emerging from the atomizing means to pass therethrough, a heater adapted to heat the atomized wash water passing through the container, temperature sensing means adapted to measure an internal temperature of the container, and control means adapted to control the heater in accordance with a signal outputted from the temperature sensing means.

In the spray type drum washing machine according to one aspect of the present invention, wash water discharged from the tub is centrifugally radially projected by the centrifugal plates, and is then atomized while passing through the diffusion net. The atomized wash water is forcibly fed by the blowing fan so that it is sprayed into the drum. Accordingly, the wash water can rapidly permeate clothes contained in the drum, so that it can more effectively come into contact with contaminants attached to the clothes. As a result, it is possible to achieve an enhancement in washing and rinsing performances while reducing the consumption of wash water.

In the spray type drum washing machine according to another aspect of the present invention, wash water is atomized in the circulation line connected between the bottom and top of the tub to circulate wash water through the tub, and is then heated while passing through the container heated by the heater, so that steam is generated. Thus, hot steam is sprayed into the tub at the top of the tub. Accordingly, it is possible to rapidly wet clothes with wash water while obtaining enhanced sterilization and washing effects.

Since wash water particle formed in accordance with the atomization of wash water is changed into steam as it is heated, it is possible to effectively perform washing of clothes at high temperature, using a reduced amount of wash water. Accordingly, it is possible to reduce waste of wash water and electrical energy.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, embodiments of a spray type drum washing machine according to the present invention will be described in detail with reference to the annexed drawings.

FIG. 3is a partially-broken perspective view illustrating a spray type drum washing machine according to an exemplary embodiment of the present invention.FIG. 4is a sectional view illustrating the spray type drum washing machine according to the illustrated embodiment of the present invention.

As shown inFIGS. 3 and 4, the spray type drum washing machine according to the illustrated embodiment of the present invention includes a base51, and a cabinet52installed on the base51while defining the appearance of the drum washing machine. The cabinet2is provided at a front wall thereof with an access opening54for loading and unloading of clothes m. A door56is hingably mounted to the front wall of the cabinet52to open and close the access opening54.

A tub60is mounted in the cabinet52to contain wash water w therein.

The tub60is provided with an access opening62arranged in rear of the access opening54of the cabinet52to allow the user to perform loading and unloading of clothes m therethrough. A gasket64is fitted around the access opening62of the tub60to prevent wash water from being leaked between the door56and the access opening54. The tub60is connected, at the bottom thereof, to a damper66mounted to the base51so that it is supported by the base51in a dampable state. The tub60is also connected, at the top thereof, to the top of the cabinet52via a spring68such that it is supported by the cabinet52in a suspended state while being dampable.

A drum70is arranged in the tub60to contain clothes.

The drum70is provided with an access opening72arranged in rear of the access openings54and62of the cabinet52and tub60to allow the user to put clothes m into the drum70and to take the clothes out of the drum70. The drum70is also formed with a plurality of water holes74at peripheral and rear walls thereof to allow wash water to flow between the tub60and the drum70. Lifters76are mounted to an inner peripheral surface of the drum70. The lifters76serve to raise clothes contained in the drum70to the top of the drum70, and then to release the clothes, thereby allowing the clothes to be dropped due to gravity.

The spray type drum washing machine also includes a drum motor80adapted to generate a drive force for rotating the drum70.

The drum motor80is mounted to a rear wall of the tub60at the outside of the tub60. The drum motor80has a rotating shaft82extending horizontally or approximately horizontally through a central portion of the rear wall of the tub60into the drum70. The rotating shaft82is connected to a central portion of a rear wall of the drum70.

Alternatively, the drum motor80may be mounted to the bottom of the tub60, as compared to the above case in which the drum motor80is mounted to the rear wall of the tub60. In this case, a separate shaft (not shown) is rotatably mounted to the rear wall of the tub60to extend horizontally or approximately horizontally through the central portion of the rear wall of the tub60into the drum70. The shaft is connected to the rotating shaft of the drum motor80via a belt.

The spray type drum washing machine further includes a water supply unit90adapted to supply wash water into the tub60, a heater100installed at the bottom of the tub60inside the tub60, and adapted to heat wash water contained in the tub60, a drainage unit110adapted to drain wash water from the tub60to the outside of the cabinet52, an atomizing device120adapted to atomize wash water drained from the tub60, a circulation line adapted to supply wash water from the tub60to the atomizing device120, and to supply the atomized wash water into the drum70, thereby circulating the wash water, and a pump122installed at the circulation line133, and adapted to cause wash water to flow forcibly along the circulation line133.

The water supply unit90includes a water supply hose94adapted to guide wash water, a detergent box96provided with a water supply passage for receiving wash water supplied through the water supply hose94, and a detergent storing space communicating with an outlet of the water supply passage while being adapted to store detergent therein, and a water supply bellows98communicating with the tub60to guide wash water emerging from the detergent box96into the tub60.

The drainage unit110includes a drainage bellows112communicating with a bottom portion of the tub60to drain wash water from the tub60, a drainage pump114adapted to pump wash water drained from the tub60through the drainage bellows112, and a drainage hose116adapted to guide the wash water emerging from the drainage pump114to the outside of the drum washing machine. In place of the drainage pump114, a drainage valve may be used. In this case, the drainage valve opens or closes the drainage bellows112to allow or prevent drainage of wash water from the tub60through the drainage bellows112.

The atomizing device120and circulation line133will be described in detail with reference toFIGS. 5 and 6.

FIG. 5is a sectional view illustrating the atomizing device and circulation line.FIG. 6is an exploded perspective view illustrating the atomizing device.

As shown inFIGS. 3 to 6, the atomizing device120includes a diffusion means including a case, through which wash water pumped by the pump122passes, centrifugal plates124adapted to centrifugally radially project wash water introduced into the case, and a diffusion net126arranged around the centrifugal plates124, and adapted to atomize the wash water centrifugally radially projected from the centrifugal plates124when the projected wash water passes therethrough, a blowing fan128adapted to forcibly feed, into the tub60, the wash water atomized while passing through the diffusion net126, and a drive means adapted to rotate both the centrifugal plates124and the blowing fan128, for example, a dual-shaft motor130.

The case includes a net case136arranged around the diffusion net126to define a flow passage for guiding the atomized wash water, and a fan case138coupled to the net case136, and arranged around the blowing fan128to define a flow passage for guiding the atomized wash water forcibly fed by the blowing fan128.

As shown inFIG. 5, the centrifugal plates124are spaced apart from each other. Although two centrifugal plates124are shown inFIG. 5, an increased number of centrifugal plates may be used. Of course, a single centrifugal plate may be used. However, the former case is preferable because wash water flowing from one centrifugal plate124to another centrifugal plate124arranged downstream from the one centrifugal plate124along a peripheral edge of the upstream centrifugal plate124without being centrifugally radially projected can be centrifugally radially re-projected from the upstream plate124, along with wash water returned to the upstream plate124after striking the diffusion net126.

As shown inFIGS. 5 and 6, the diffusion net126may have a circular strip structure having a height greater than the total height of the centrifugal plates124such that it completely surround the centrifugal plates124. Alternatively, the diffusion net126may have a top portion upwardly spaced apart from an uppermost one of the centrifugal plates124, a bottom portion downwardly spaced apart from a lowermost one of the centrifugal plates124, and a peripheral portion arranged around the centrifugal plates124, so that the diffusion net126completely surrounds the centrifugal plates124.

As shown inFIGS. 5 and 6, the dual-shaft motor130includes a rotating shaft131aextending axially through respective rotating centers of the centrifugal plates124to firmly support the centrifugal plates124, and a rotating shaft131b extending axially through a rotating center of the blowing fan126to firmly support the blowing fan126, as shown inFIGS. 5 and 6. The dual-shaft motor130is arranged between the centrifugal plates124and the blowing fan128.

As shown inFIGS. 3 to 6, the circulation line133includes a pump hose132connected, at one end thereof, to a drainage port formed at the tub60while being connected, at the other end thereof, to an inlet of the pump122, in order to guide wash water from the tub60into the pump122. The circulation line133also includes a first circulation pipe134connected, at one end thereof, to an outlet of the pump122while being connected, at the other end thereof, to the net case136such that the other end thereof is spaced apart from the centrifugal plates124. The first circulation pipe134guides wash water pumped by the pump122into the net case136. The circulation line133further includes a second circulation pipe140adapted to guide, into the drum70, wash water forcibly fed by the blowing fan128in an atomized state.

The pump hose132may have, at a middle portion thereof, a bellows portion to prevent the ends thereof connected to the tub60and pump122from being separated from the tub60and pump122.

The first circulation pipe134extends through the net case136such that the end thereof arranged in the interior of the net case136is spaced apart from a lower surface of the lowermost centrifugal plate124.

The net case136is provided, at a wall thereof, with a through hole136aadapted to allow the first circulation pipe134to extend therethrough. In the illustrated case, the through hole136ais formed at the bottom wall136cof the net case136. The net case136is also provided, at a wall thereof facing the fan case138, that is, the top wall thereof, with an opening136badapted to allow the forcibly fed atomized wash water to be introduced into the fan case138. The net case136is also provided with a suction hole136e, at the wall thereof having the through hole136a, that is, the bottom wall136cthereof, to suck air into the interior of the net case136. Although the suction hole136eis formed at the bottom wall136cof the net case136in the illustrated case, it may be formed at a peripheral wall136dof the net case136.

The fan case138is provided, at a wall thereof facing the net case136, that is, the bottom wall thereof, with an opening138ato receive the atomized wash water from the net case136. A discharge hole138bis provided at the top wall of the fan case138to discharge the atomized wash water from the fan case138.

The second circulation pipe140is connected, at one end thereof, to the discharge hole138bof the fan case138. The second circulation pipe140extends upwardly from the discharge hole138bsuch that the other end thereof is upwardly protruded through a top portion of the gasket64.

As shown inFIGS. 3 and 4, it is preferred that the other end of the second circulation pipe140be inclinedly arranged toward the center of the interior of the drum70.

A trumpet-shaped diffusion nozzle146is mounted to the other end of the second circulation pipe140to allow the atomized wash water injected into the interior of the drum70to be spread in a diffused state.

InFIGS. 5 and 6, reference numeral152designates support rods adapted to firmly hold the diffusion net126in the net case136in a state of being spaced apart from the bottom of the net case136. Reference numeral154designates a motor mounting member adapted to fixedly mount the dual-shaft motor130to the fan case138.

Now, operation of the drum washing machine having the above described configuration according to the illustrated embodiment of the present invention will be described.

When the drum washing machine is operated under the condition in which the door56has been closed after clothes m have been put into the drum70, as shown inFIGS. 3 and 4, wash water is supplied from the water supply unit90into the tub6, so that it is contained in a bottom portion of the tub6while being contained in the pump hose132.

In this state, the bottom portion of the drum70is also dipped in the wash water as the wash water is introduced into the drum70through the water holes74. As a result, the clothes in the drum70are wetted by the wash water.

Thereafter, the drum motor80is driven to rotate the drum70. Thus, the clothes m contained in the drum70are repeatedly raised and dropped in the drum70. As a result, stains are removed from the clothes m in accordance with action of the wash water.

Meanwhile, both the pump122and the dual-shaft motor130are driven during the above described water supply cycle or wash cycle executed in the spray type drum washing machine. Accordingly, the wash water in the tub60is pumped by the pump122. Also, the centrifugal plates124and blowing fan128are rotated in accordance with the operation of the dual-shaft motor130.

The wash water pumped by the pump122is guided into the net case136via the first circulation pipe134, and then strikes one surface of each centrifugal plate124. Thereafter, the wash water is centrifugally radially projected toward the diffusion net126while being guided by the centrifugal plates124, so that it is atomized while passing through the diffusion net126.

The wash water atomized while passing through the diffusion net126is forcibly fed by the blowing fan128so that it is introduced into the second circulation pipe140. The atomized wash water is then sprayed in the form of rain or mist into the drum70through the gasket64as it is discharged from the second circulation pipe140.

The atomized wash water sprayed into the drum70through the gasket64directly wets the clothes m contained in the drum70, so that it rapidly reacts upon contaminants attached to the clothes m, thereby enhancing the washability thereof.

After completion of the above described wash cycle, the wash water existing in the tub60in a contaminated state is externally drained from the tub60through the drainage unit110.

Subsequently, the spray type drum washing machine performs, several times, a rinse cycle for rinsing the washed clothes m to remove bubbles remaining on the clothes m. In this rinse cycle, wash water is supplied into the tub60through the water supply unit90. Thereafter, the drum motor80is driven to rotate the drum70, thereby causing the clothes m contained in the drum70to be repeatedly raised and dropped in the drum70. As a result, bubbles are removed from the clothes m.

Meanwhile, both the pump122and the dual-shaft motor130are driven during the above described water supply cycle or rinse cycle executed in the spray type drum washing machine. Similarly to the wash cycle, accordingly, the wash water in the tub60is pumped by the pump122, and then atomized by the centrifugal plates124and diffusion net126. Subsequently, the atomized wash water directly wets the clothes m contained in the drum70, so that it rapidly rinses the clothes m to remove bubbles from the clothes m in accordance with an enhanced rinse ability thereof.

After completion of the above described rinse cycle, the wash water existing in the tub60in a contaminated state is externally drained from the tub60through the drainage unit110.

After performing the rinse cycle several times, the drum washing machine performs a spin-dry cycle to remove moisture form the clothes m. That is, when the drum motor80rotates the drum70at high speed, moisture permeated into the clothes m is centrifugally removed from the clothes m, and then collected in the bottom portion of the tub60after being discharged from the drum70through the water holes74. Finally, the collected moisture is externally drained through the drainage unit110.

FIG. 7is a partially-broken perspective view illustrating a spray type drum washing machine according to another embodiment of the present invention.FIG. 8is a sectional view illustrating the spray type drum washing machine according to the embodiment of the present invention illustrated inFIG. 7.

As shown inFIGS. 7 and 8, the spray type drum washing machine according to this embodiment of the present invention includes a cabinet152defining the appearance of the drum washing machine, and a tub156mounted in the cabinet152such that it is connected, at the top thereof, to the top of the cabinet152via a spring154in a suspended state while being supported by a damper155. The drum washing machine also includes a drum158rotatably mounted in the tub156, and adapted to contain wash water and clothes m to be washed, and lifters159mounted to an inner peripheral surface of the drum158such that they are radially protruded from the inner peripheral surface of the drum158while being circumferentially uniformly spaced apart from one another. The lifters159serve to raise clothes contained in the drum158to the top of the drum158, and then to release the clothes, thereby allowing the clothes to be dropped. The drum washing machine further includes a drum motor160connected with the drum158, and adapted to rotate the drum158, a water supply unit162, and a detergent box164. The water supply unit .162and detergent box164are arranged above the tub156to simultaneously supply wash water and detergent into the tub156and drum158.

The spray type drum washing machine further includes a circulation pump170installed at a circulation line172adapted to connect the bottom and top of the tub156, and adapted to pump wash water from the bottom of the tub156to the top of the tub156via the circulation line172or to drain wash water from the tub156via a drainage line174, an atomizing device180installed at the circulation line172such that it is connected to the circulation pump170, and adapted to atomize wash water discharged from the circulation pump170, and a steam generating device190installed at the circulation line172such that it is connected to the atomizing device180, and adapted to heat wash water particulates emerging from the atomizing device180, thereby changing the wash water particulates into steam.

The circulation line172extends vertically to connect the bottom and top of the tub156. The circulation pump170is installed at a lower portion of the circulation line172connected to the bottom of the tub156. The atomizing device180is installed at the circulation line172downstream from the circulation pump170. The steam generating device190is installed at an upper portion of the circulation line172connected to the top of the tub156.

The atomizing device180and steam generating device190will be described in detail with reference toFIGS. 9 and 10.

FIG. 9is a sectional view illustrating the atomizing device.FIG. 10is a sectional view illustrating the steam generating device.

The atomizing device180includes a case182installed at the circulation line172while being provided at a peripheral wall thereof with a suction port181for receiving wash water, and at a top wall thereof with a discharge port183for discharging wash water particulates, a blowing fan184rotatably mounted in the case182, and adapted to blow the wash water particulates, and a dual-shaft motor185mounted in the case182beneath the blowing fan184such that it is connected with the blowing fan184, and adapted to rotate the blowing fan184. The atomizing device180also includes a plurality of centrifugal plates186arranged in the case182beneath the dual-shaft motor185such that it is connected to the dual-shaft motor185, and adapted to rotate simultaneously with the blowing fan184, thereby radially projecting the wash water introduced into the case182in accordance with a centrifugal force caused by the rotation thereof, and a diffusion net188arranged around the centrifugal plates186in a state of being spaced apart from the centrifugal plates186, and adapted to atomize the wash water radially projected from the centrifugal plates186.

The dual-shaft motor185is arranged in the case182in a state of being radially supported by the case182. The dual-shaft motor185has upper and lower rotating shafts respectively connected to the blowing fan184and the centrifugal plates186.

InFIG. 9, reference numeral189designates a motor mounting member adapted to mount the dual-shaft motor185to the case182.

The steam generating device190includes a container192having an inlet191adapted to receive wash water particulates discharged from the atomizing device180, and an outlet193arranged opposite to the inlet191, and adapted to discharge steam, a heater194arranged on an outer surface of the container192, and adapted to heat the container192, and a temperature sensor196adapted to sense an internal temperature of the container192, thereby allowing a control unit included in the drum washing machine to control operation of the heater194, based on the temperature of steam existing in the container192.

Of course, the container192is made of a material exhibiting a relatively high heat transfer coefficient. The heater194may be mounted to the bottom of the container192. Also, the temperature sensor196may be mounted to the top of the container192while being electrically connected to the heater194.

Meanwhile, the circulation line172extends, at an upper end thereof, through a gasket175arranged between the tub156and the cabinet152to prevent leakage of wash water. A diffusion nozzle173adapted to spray wash water or steam is mounted to the upper end of the circulation line172such that it is directed from the top and front end of the tub156toward the bottom and rear end of the tub156.

Now, operation of the drum washing machine having the above described configuration according to the embodiment of the present invention illustrated inFIGS. 7 to 10will be described.

When a wash cycle is begun under the condition in which clothes m have been put into the drum158, a water supply valve (not shown) is opened, so that wash water is introduced into the water supply unit162and detergent box164. As a result, the wash water is supplied into the tub156and drum158, along with detergent. The amount of wash water supplied into the tub156is appropriately determined, based on the amount of clothes contained in the tub156.

Under the condition in which an appropriate amount wash water has been supplied into the tub156, the drum motor160is operated to rotate the drum158. In accordance with the rotation of the drum158, the lifters159raise the clothes m contained in the drum158, and then release the clothes m at a certain level in the drum158, thereby allowing the clothes m to be dropped. Thus, the wash cycle is executed.

When the circulation pump170is operated during the execution of the wash cycle in accordance with an associated operating condition set by the user, the wash water contained in the tub156is pumped from the bottom of the tub156to the top of the tub156, and sprayed into the tub156, so that effective flows of wash water are formed. In addition to such effective flows of wash water, an effect of beating the clothes m with the wash water is generated. Thus, an enhancement in washing performance is obtained.

In accordance with the operating condition set by the user, the dual-shaft motor185and heater194are operated, simultaneously with the operation of the circulation pump170to pump wash water into the circulation line172. Accordingly, the wash water introduced from the bottom of the tub156into the circulation line172is sprayed into the tub156at the top of the tub156after being atomized and then changed into steam while sequentially passing through the atomizing device180and steam generating device190.

This will be described in more detail. The wash water pumped by the circulation pump170is introduced into the case182via the circulation line172. As the dual-shaft motor185operates, the blowing fan184and centrifugal plates186are rotated. As a result, the wash water introduced into the case182is radially projected after striking the centrifugal plates186, and is than atomized in the form of particulates while passing through the diffusion net188. The wash water particulates emerging from the diffusion net188are then discharged from the case182by the blowing fan184. Thus, the wash water particulates are discharged from the atomizing device180.

The wash water particulates discharged from the atomizing device180are introduced into the container192via the circulation line172. As the heater194operates, the wash water particulates are heated while passing through the container192, so that they are changed into hot steam. The hot steam is then sprayed into the tub156at the top of the tub156after passing through the circulation line172.

Of course, the heater194is controlled by the temperature sensor196, based on the temperature of steam in the container192.

Thus, wash water is pumped from the bottom of the tub156during the wash cycle to pass through the atomizing device180and steam generating device190, so that it is changed into hot steam, and then sprayed into the tub156at the top of the tub156. Accordingly, it is possible to achieve an enhancement in washing and sterilization performances.

Where the above procedure is carried out prior to the supply of wash water into the tub156, it is possible to rapidly wet the clothes by the hot steam, and thus, to achieve an enhancement in washing performance.

After completion of the wash cycle, the circulation pump170is operated in a state of being connected to the drainage line174, so that it drains the wash water contained in the tub156. After the drainage of wash water, the drum motor160is driven at high speed, so that the drum158is rotated at high speed to perform an intermittent spin-dry cycle for extracting wash water from the clothes in accordance with a centrifugal force generated during the rotation of the drum158. After the spin-dry cycle, the water supply valve is re-opened to supply wash water into the drum158. Simultaneously, the drum158is rotated. Thus, a rinse cycle is executed.

After repeated execution of the rinse cycle and intermittent spin-dry cycle, a spin-dry cycle is finally executed. Thus, washing of the clothes is completed.

As apparent from the above description, in the spray type drum washing machine according to the first embodiment of the present invention, wash water discharged from the tub is centrifugally radially projected by the centrifugal plates, and is then atomized while passing through the diffusion net. The atomized wash water is forcibly fed by the blowing fan so that it is sprayed into the drum. Accordingly, the wash water can rapidly permeate clothes contained in the drum, so that it can more effectively come into contact with contaminants attached to the clothes. As a result, it is possible to achieve an enhancement in washing and rinsing performances while reducing the consumption of wash water.

In the spray type drum washing machine according to the second embodiment of the present invention, wash water is atomized in the circulation line connected between the bottom and top of the tub to circulate wash water through the tub, and is then heated while passing through the container heated by the heater, so that steam is generated. Thus, hot steam is sprayed into the tub at the top of the tub. Accordingly, it is possible to rapidly wet clothes with wash water while obtaining enhanced sterilization and washing effects.

Since wash water particle formed in accordance with the atomization of wash water is changed into steam as it is heated, it is possible to effectively perform washing of clothes at high temperature, using a reduced amount of wash water. Accordingly, it is possible to reduce waste of wash water and electrical energy.