Laundry treatment apparatus

A laundry treatment apparatus includes a drum rotatably supported within a cabinet and configured to receive laundry therein, a connection duct into which air inside the drum is discharged, and a discharge duct that extends in a longitudinal direction of the drum and that is connected to the connection duct. The laundry treatment apparatus also includes a filter assembly including a filter unit located in the discharge duct to filter air and an impurity remover unit configured to remove and compress impurities remaining on the filter unit.

Pursuant to 35 U.S.C. §119(a), this application claims the benefit of Korean Patent Application No. 10-2012-0157984, filed on Dec. 31, 2012, which is hereby incorporated by reference as if fully set forth herein.

FIELD

The present disclosure relates to a laundry treatment apparatus.

BACKGROUND

A laundry treatment apparatus is a generic term of home appliances including a washing machine for washing laundry, a dryer for drying laundry, and a combined drying and washing machine for both washing and drying laundry.

In addition, a laundry treatment apparatus capable of drying laundry (e.g., washed clothing) may be classified into an exhaust type laundry treatment apparatus and a circulation type laundry treatment apparatus.

More specifically, a laundry treatment apparatus may be classified into the exhaust type laundry treatment apparatus which is configured to exhaust hot and humid air discharged from a drum to the outside of the laundry treatment apparatus, and the circulation type laundry treatment apparatus that uses a heat exchanger that implements condensation and heating of air discharged from the drum while hot and humid air discharged from the drum is resupplied into the drum (e.g., during circulation of air discharged from the drum).

The air discharged from the drum during drying may contain impurities (e.g., lint, etc.) dropped from an object to be dried, such as laundry. Accumulation of the impurities on internal components of the laundry treatment apparatus may cause breakdown of the laundry treatment apparatus, and the impurities discharged outward from the laundry treatment apparatus may cause air contamination of an indoor space where the laundry treatment apparatus is placed. Therefore, laundry treatment apparatus having a drying function may remove the impurities from the air discharged from the drum.

A laundry treatment apparatus having a drying function may include a connection duct arranged in a height direction of a drum, and a discharge duct arranged in a longitudinal direction of the drum. The connection duct may be provided with a filter to filter air discharged from the drum.

SUMMARY

In one aspect, a laundry treatment apparatus includes a cabinet defining an external appearance of the laundry treatment apparatus, a drum rotatably supported within the cabinet and configured to receive laundry therein, and a connection duct into which air inside the drum is discharged. The laundry treatment apparatus also includes a discharge duct that extends in a longitudinal direction of the drum and that is connected to the connection duct. The laundry treatment apparatus further includes a filter assembly including a filter unit located in the discharge duct and configured to filter air, and an impurity remover unit configured to remove impurities remaining on the filter unit and compress impurities removed from the filter unit. In addition, the laundry treatment apparatus includes a drive unit configured to reciprocate the impurity remover unit along the filter unit.

Implementations may include one or more of the following features. For example, the cabinet may have a filter insertion hole that communicates with the discharge duct and the filter assembly may pass through the filter insertion hole based on the filter assembly being inserted into the discharge duct or separated from the discharge duct. In this example, the filter assembly may include a housing in which the impurity remover unit is received. The housing may be configured to store impurities removed from the filter unit by the impurity remover unit.

In some implementations, the filter unit may include a filter frame located at an upper side of the housing, an air introduction hole defined in the filter frame and configured to allow air introduced into the discharge duct to be introduced into the housing and a filter attached to the filter frame and configured to filter air moving from the housing to the discharge duct. In these implementations, the impurity remover unit may include a compressor located within the housing and configured to compress impurities within the housing by reciprocating within the housing based on force generated by the drive unit and a brush secured to the compressor and configured to separate, from the filter, impurities remaining on the filter. Further, in these implementations, the impurity remover unit may include a rack arranged in a longitudinal direction of the housing and connected to the compressor and the drive unit may include a rack gear rotatably coupled to the filter frame and engaged with the rack, and a motor gear located in the discharge duct and separably coupled to the rack gear.

The filter assembly may include a rack retraction preventing member located in the housing and configured to guide the rack in a manner that prevents the rack from being retracted outward from the housing during movement of the compressor. The rack may include a first rack and a second rack respectively provided at opposite ends of the compressor and the rack gear may include a first rack gear rotatably supported at the filter frame and engaged with the first rack, a second rack gear rotatably supported at the filter frame and engaged with the second rack, and a connection shaft configured to connect the first rack gear and the second rack gear to each other. The motor gear may be secured to a motor rotating shaft that is rotated by a motor. The motor may be located at an exterior of the discharge duct and the motor gear may be located within the discharge duct.

In addition, the filter frame may include a first frame having the air introduction hole and a second frame rotatably coupled to the first frame via the connection shaft. The second frame may be separable from the housing. Further, the compressor may include a compression plate configured to reciprocate within the housing and a plurality of through-holes perforated in the compression plate. The brush may be secured to the compression plate.

In some examples, the filter assembly may include a scraper located at the filter frame and configured to separate impurities from the brush. In these examples, the filter assembly may include a rib configured to support the filter, the scraper may have a plurality of scraper bosses protruding from the rib and spaced apart from one another by a predetermined distance, and the brush may have a plurality of brush bosses protruding from the compressor toward the filter and spaced apart from one another by a predetermined distance. In addition, in these examples, the plurality of brush bosses may pass through spaces between adjacent scraper bosses.

In some implementations, the apparatus may include a position sensing unit configured to sense a position of the impurity remover unit. In these implementations, the position sensing unit may include a magnetism generator secured to the impurity remover unit and a magnetism sensor configured to generate a control signal based on the magnetism generator reaching a preset position. Further, in these implementations, the filter assembly may include a housing in which the impurity remover unit is received such that impurities, removed from the filter unit by the impurity remover unit, are stored in the housing, a first hole perforated in a bottom surface of the housing, and a second hole perforated in the bottom surface of the housing and spaced apart from the first hole by a predetermined distance. The magnetism sensor may be a first magnetism sensor secured within the discharge duct at a position below the first hole and the apparatus may include a second magnetism sensor secured within the discharge duct at a position below the second hole.

In some examples, the discharge duct may include a path guide configured to guide air discharged from the connection duct to the air introduction hole and the filter assembly may include a frame guide that protrudes from an upper surface of the filter frame and contacts the path guide. In these examples, the filter assembly may include a guide slope configured to connect an upper surface of the frame guide and the upper surface of the filter frame to each other and the discharge duct may include a first duct guide configured to contact the guide slope and a second duct guide configured to contact the upper surface of the filter frame based on the filter assembly being inserted into the discharge duct.

In some implementations, the cabinet may include a rear panel having an air outlet through which air, discharged from the drum through the discharge duct, is discharged to outside of the cabinet and a base panel located below the drum. In these implementations, the rear panel may be secured to the base panel and the base panel may have a duct guide configured to guide positioning of the discharge duct in a manner that facilitates coupling of the discharge duct to the air outlet.

In some examples, the duct guide may include at least one position guide configured to guide both lateral sides of the discharge duct to coincide with both lateral sides of the air outlet and at least one height guide configured to guide a top and bottom of an outer peripheral surface of the discharge duct to coincide with a top and bottom of an outer periphery of the air outlet. In these examples, each of the at least one position guide and the at least one height guide includes a first plate and a second plate extending perpendicular to the first plate with the second plate having a slope, the at least one position guide includes at least one pair of position guides each secured to the base panel via the second plate, and the at least one height guide is secured to the base panel via the first plate.

In some implementations, the filter unit may include two cover frames extending from opposite ends of the filter frame and configured to receive opposite surfaces of the housing and covers located respectively at the cover frames and each being configured to define a predetermined space between the cover frame and the cover. In these implementations, the filter unit may include a connection plate slit in each of the cover frames that extends in a longitudinal direction of the housing, and the drive unit may include a first rack and a second rack, each of which is secured to the compressor through the connection plate slit and located in a space between the cover frame and the cover. The drive unit also may include a first intermediate gear rotatably coupled to a first cover frame and configured to reciprocate the first rack in a longitudinal direction of the housing and a second intermediate gear rotatably coupled to a second cover frame and configured to reciprocate the second rack in a longitudinal direction of the housing, a separable gear rotatably coupled to a first cover and configured to penetrate the first cover to thereby be engaged with the first intermediate gear, a connection shaft penetrating the first and second cover frames, a first connection gear located on the connection shaft and engaged with the first intermediate gear, and a second connection gear located on the connection shaft and engaged with the second intermediate gear. The drive unit further may include a motor secured to an exterior of the discharge duct and having a rotating shaft penetrating the discharge duct and a motor gear secured to the rotating shaft and located within the discharge duct. The separable gear may be connected to the motor gear.

In some examples, the drive unit may include a first rack gear rotatably coupled to the first cover frame and configured to connect the first intermediate gear and the first rack to each other and a second rack gear rotatably coupled to the second cover frame and configured to connect the second intermediate gear and the second rack to each other. In these examples, the first rack and the second rack may have a same configuration and the first rack may include a rack body having a shape of a bar, a geared portion protruding from a surface of the rack body and engaged with the first rack gear, and a connection plate located at the rack body and configured to be inserted into the connection plate slit to thereby be coupled to the compressor.

In some implementations, the filter unit may include a rack guide provided at each of the first and second cover frames and configured to guide movement of the first rack or the second rack. In these implementations, the rack guide may include a rack body receiving portion in which the rack body is received. The rack body receiving portion may extend from a bottom of the connection plate slit to a lower portion of the cover frame. The rack guide also may include a gear receiving portion in which the geared portion is received. The gear receiving portion extends from the rack body receiving portion toward an upper portion of the cover frame.

The rack body receiving portion may extend in a longitudinal direction of the connection plate slit and may be spaced apart from the connection plate slit by a distance equal to or less than a thickness of the rack body. Also, the rack guide may include a rack body support portion located within the rack body receiving portion and configured to contact an upper surface of each rack body.

In some examples, the filter assembly may include a housing having a storage space configured to store impurities, an air introduction hole perforated in the housing, through which air introduced into the discharge duct is introduced into the storage space through the air introduction hole, and a housing through-hole perforated in the housing, the filter unit being located at the housing through-hole. In these examples, the impurity remover unit may be rotatably supported within the housing and may be configured to separate, from the filter unit, impurities remaining on the filter unit and to compress impurities separated from the filter unit within the housing.

In some implementations, the impurity remover unit may include a brush frame located within the housing and configured to reciprocate over a predetermined area of the filter unit, the brush frame compressing impurities within the housing. In these implementations, the impurity remover unit also may include a brush located at the brush frame and configured to contact the filter unit and a brush rotating shaft configured to rotatably secure the brush frame to the housing. In addition, in these implementations, the drive unit may include a motor secured to the discharge duct, a driving gear coupled to a rotating shaft of the motor and located within the discharge duct, and a driven gear provided on the brush rotating shaft and located at an exterior of the housing so as to be engaged with the driving gear.

DETAILED DESCRIPTION

A laundry treatment apparatus100, as shown inFIG. 1, includes a cabinet1defining an external appearance of the laundry treatment apparatus100, a drum2rotatably placed within the cabinet1, the drum2being configured to receive laundry therein, an air supply unit3configured to supply heated air (e.g., hot air) or unheated air into the drum2, a discharge path4configured to discharge air outwardly from the drum2, and a filter assembly5(seeFIG. 3) configured to remove impurities from the air discharged from the drum2.

The cabinet1is constituted of a front panel11having an opening111, a rear panel13having an air inlet131that communicates with the interior of the drum2, and a base panel15located below the drum2. The front panel11and the rear panel13are supported by the base panel15.

A user may put or take laundry into or out of the drum2through the opening111. The opening111is opened or closed by a door113that is rotatably secured to the front panel11.

A control panel115may be attached to the front panel11. The control panel115is provided with an input unit that allows a user to input control instructions to the laundry treatment apparatus100and a display unit that displays control details of the laundry treatment apparatus100.

The rear panel13is located opposite to the front panel11so as to face the front panel11(e.g., the rear panel13is spaced apart from the front panel11by a predetermined distance in a longitudinal direction of the drum2). The air inlet131is perforated in the rear panel13to allow air supplied from the air supply unit3to be introduced into the drum2.

The rear panel13may further have an air outlet133, through which the air discharged from the drum2through the discharge path4moves outward from the cabinet1.

The rear panel13may further have a rear support flange135configured to rotatably support a rear surface of the drum2. This will be described later in more detail.

The base panel15serves to support the laundry treatment apparatus100on the ground. The front panel11and the rear panel13are secured to the base panel15.

The base panel15may have duct guides151and153(seeFIG. 2(a)) configured to facilitate assembly of a discharge duct43provided in the discharge path4and the air outlet133perforated in the rear panel13. This will be described later in more detail.

A drum support structure17is further provided within the cabinet1to rotatably support a front surface of the drum2. The drum support structure17includes a support body171secured to an inner surface of the cabinet1and a support structure through-hole173perforated in the support body171for communication between the opening111and the interior of the drum2.

Accordingly, laundry introduced into the cabinet1through the opening111may move into the drum2through the support structure through-hole173.

The drum support structure17may further include a front support flange175configured to rotatably support the front surface of the drum2. The front support flange175is formed at an outer periphery of the support structure through-hole173.

In this case, the diameter of the front support flange175may be greater than the diameter of the support structure through-hole173in consideration of the diameter of the drum2.

The drum2may have the shape of a cylinder, the front surface and the rear surface of which are open. As described above, the front surface of the drum2is rotatably supported by the front support flange175, and the rear surface of the drum2is rotatably supported by the rear support flange135.

A drum drive unit is provided to rotate the drum2. The drum drive unit may include a drum motor21, and a belt23that connects a rotating shaft of the drum motor21and an outer peripheral surface of the drum2to each other.

The air supply unit3serves to supply heated air or unheated air into the drum2to allow heat exchange between laundry and the air. The air supply unit3may include a heater housing31formed at the rear panel13, a heater (e.g., a device configured to increase temperature of air passing through the heater housing31)33accommodated in the heater housing31, and a fan35located in the discharge path4(more particularly, located in a connection duct41or the discharge duct43).

The heater housing31is configured to enclose the air inlet131perforated in the rear panel13, and has a housing inlet311for introduction of air into the heater housing31.

Providing the heater housing31at the exterior of the cabinet1, rather than the interior of the cabinet1, may increase the drying capacity of laundry.

If the quantity of laundry increases, it may be necessary to supply a greater quantity of air into the drum2to achieve drying of laundry within a predetermined time. Accordingly, to dry a large quantity of laundry, the laundry treatment apparatus100may increase the quantity of air supplied into the drum2, and may employ a large capacity heater to heat a large quantity of air.

If the large capacity heater is placed within the cabinet1, however, the volume of the cabinet1is increased. Moreover, the large capacity heater may increase an internal temperature of the cabinet1, which may cause damage to internal components within the laundry treatment apparatus100.

To address these issues, in the laundry treatment apparatus100, the air supply unit3is secured to the exterior of the cabinet1. As such, the laundry treatment apparatus100may be utilized as a commercial laundry treatment apparatus that is capable of drying large amounts of laundry per load.

The discharge path4, as described above, serves to discharge air inside the drum2to the outside of the cabinet1. The discharge path4may include the connection duct41arranged in a height direction of the drum2, and the discharge duct43arranged in a longitudinal direction of the drum2, through which air supplied from the connection duct41is discharged to the outside of the cabinet1.

The connection duct41is located below the opening111(in front of the support structure through-hole173) and serves to move air inside the drum2to the discharge duct43. That is, the connection duct41connects an outer periphery of the opening111and a duct connection hole (435, seeFIG. 2(a)) of the discharge duct43to each other.

The discharge duct43is configured to connect the connection duct41and the air outlet133to each other and serves to discharge the air discharged from the drum2through the connection duct41to the outside of the cabinet1.

In this case, the fan35included in the air supply unit3may be secured to the exterior of the cabinet1to suction air from inside the discharge duct43.

To dry a large quantity of laundry, as described above, large air volume may be used. However, it may not be easy to install a large capacity fan within the cabinet1having a limited volume.

Accordingly, as shown inFIG. 1, the fan35is secured to the rear panel13to outwardly discharge air inside the drum2through the air outlet133, which enables installation of a large capacity fan without a change in the size of the cabinet1.

The discharge duct43, as shown inFIG. 2(a), may be first assembled with the base panel15located below the drum2after the drum2is assembled with the base panel15.

In this case, for assembly of the discharge duct43, a worker needs to push the discharge duct43from the front side of the drum2toward the rear panel13in order to couple the discharge duct43into the air outlet133of the rear panel13. However, if the drum2obstructs a worker's field of vision, the worker may have difficulty in coupling the discharge duct43into the air outlet133.

Accordingly, the base panel15may be provided with the duct guides151and153to facilitate coupling of the discharge duct43and the air outlet133.

The duct guides may include at least one pair of position guides151and at least one height guide153. The position guides151assist in positioning both lateral sides of the discharge duct43to coincide with both lateral sides of the air outlet133, and the at least one height guide153assists in positioning the top and bottom of an outer peripheral surface of the discharge duct43to coincide with the top and bottom of an outer periphery of the air outlet133.

Providing the position guide151and the height guide153with the same configuration may be advantageous in terms of reduction of manufacturing costs. To this end, each of the position guide151and the height guide153may include a first plate1511and a second plate1513extending perpendicular to the first plate1511, the second plate1513having a slope1515.

The position guide151is secured to the base panel15via the second plate1513, whereas the height guide153is secured to the base panel15via the first plate1511.

Accordingly, once the discharge duct43is inserted into a space defined by the pair of position guides151, both lateral sides of the discharge duct43may be moved to positions where both lateral sides of the discharge duct43coincide with both lateral sides of the air outlet133under guidance of the first plates1511of the position guides151.

While the discharge duct43is moved toward the air outlet133, the bottom of the outer peripheral surface (e.g., a bottom surface) of the discharge duct43is adjustable in height by the slope1515of the height guide153. In this manner, the top and bottom of the outer peripheral surface of the discharge duct43may coincide with the top and bottom of the outer periphery of the air outlet133.

If the width of the discharge duct43, as shown inFIG. 2, is not constant, the position guides151may include a pair of front position guides arranged on the base panel15at the front side of the discharge duct43, and a pair of rear position guides arranged on the base panel15at the rear side of the discharge duct43(e.g., arranged at positions adjacent to the air outlet133).

The filter assembly5included in the laundry treatment apparatus100is arranged in a direction parallel to the rotating axis C of the drum2(e.g., in a longitudinal direction of the drum2) to filter air discharged from the drum2.

More specifically, the filter assembly5included in the laundry treatment apparatus100is separably coupled to the discharge duct43, rather than the connection duct41, thereby filtering air discharged from the drum2.

In some laundry treatment apparatus, the connection duct41is provided with a filter. However, the length of the connection duct41is not variable so long as the height of the laundry treatment apparatus is not varied, which may make it difficult to increase the filtration capacity of the filter.

The laundry treatment apparatus100may achieve a significant increase in the filtration capacity of the filter assembly5because the filter assembly5is provided in the discharge duct43extending in a longitudinal direction of the drum2(e.g., parallel to the rotating axis C of the drum2).

Accordingly, the laundry treatment apparatus100may be utilized as a commercial laundry treatment apparatus that is capable of drying large amounts of laundry per load.

The filter assembly5may be separably coupled to the discharge duct43. To this end, the front panel11may be provided with a filter support panel19.

As shown inFIG. 3, the filter support panel19has a filter insertion hole191for insertion of the filter assembly5. The filter support panel19may be located below the front panel11(e.g., below the door13).

Hereinafter, a configuration of the filter assembly5will be described with reference toFIGS. 3 and 4.

The filter assembly5includes a housing51defining a storage space511in which impurities are stored. The housing51is configured to be inserted into the discharge duct43through the filter insertion hole191of the filter support panel19. The housing51may be provided at a front surface thereof with a handle513to facilitate introduction and retraction of the housing51.

The housing51may be a hexahedral housing, one side of which faces the connection duct41and is open. In this case, a filter unit53is located at the open side of the housing51.

An impurity remover unit B is accommodated in the housing51and serves to remove impurities remaining on the filter unit53and compress the impurities removed from the filter unit53within the housing51.

The impurity remover unit B may include a brush57configured to separate impurities remaining on the filter unit53, and a compressor55configured to compress the impurities separated by the brush57within the storage space511. This will be described later in more detail.

The filter unit53includes a filter frame531located at the open side of the housing51and a filter533secured to the filter frame531.

The filter frame531has an air introduction hole5317communicating with the duct connection hole435. Accordingly, the air discharged from the drum2through the connection duct41is introduced into the housing51through the duct connection hole435and the air introduction hole5317, and, in turn, the air introduced into the housing51is discharged outward from the housing51(e.g., from the interior of the discharge duct43) by way of the filter533.

In this case, the discharge duct43may further be provided with a path guide (431, seeFIG. 9) to allow air discharged from the connection duct41to move to the air introduction hole5317.

The filter frame531may include a first frame5311having the air introduction hole5317, and a second frame5313rotatably coupled to the first frame5311. This structure may facilitate removal of impurities stored in the storage space511of the housing51.

When removal of impurities stored in the housing51is needed, the user first retracts the filter assembly5from the discharge duct43, and then separates the filter frame531from the housing51, in order to remove impurities stored in the housing51.

The filter assembly5included in the laundry treatment apparatus100may be designed to attempt to maximize air filtration capacity, which may result in increase in the size and weight of the housing51. Accordingly, if the filter frame531is constructed by a single frame, the user may be inconvenienced by having to remove impurities within the housing51due to the weight of the filter assembly5.

However, the filter frame531may reduce the above-described problem because the filter frame531includes the first frame5311and the second frame5313, and the second frame5313is rotatably coupled to the first frame5311and is separable from the housing51.

In addition, the filter frame531may have a rack gear receiving portion5315in which a rack gear65that will be described in more detail hereinafter is received. The rack gear receiving portion5315may be provided at a junction (e.g., boundary) between the first frame5311and the second frame5313.

As described above, the impurity remover unit B may include the brush57and the compressor55.

The brush57is configured to reciprocate within the housing51(more particularly, within the storage space511) and serves to separate impurities remaining on the filter533. The compressor55is configured to reciprocate within the housing51and serves to compress impurities stored in the storage space511.

Accordingly, if the brush57is located at an upper surface of the compressor55to come into contact with the filter533as shown inFIG. 4, both the brush57and the compressor55may be operated using only a single drive unit6(e.g., brush drive unit) that serves to reciprocate the brush57within the storage space511.

The compressor55may include a compression plate551placed within the housing51, and a first rack554and a second rack555located respectively at opposite ends of the compression plate551.

Each of the first rack554and the second rack555may include a bar-shaped body and gears protruding from the body at a constant interval.

In this case, a rack guide59is provided in the open side of the housing51to guide movement of the racks554and555.

That is, the rack guide59is interposed between the filter frame531and the housing51and serves to guide movement of the first rack554and the second rack555.

To this end, the rack guide59may include a guide body591supported by the open upper side of the housing51, and rack receiving portions593protruding from an upper surface of the guide body591to enable seating of the first rack554and the second rack555on the rack guide59.

Each of the rack receiving portions593may include a first guide plate5931formed at a longitudinal outer edge of the guide body591, and a second guide plate5933spaced apart from the first guide plate5931by a sufficient distance to receive the first rack554or the second rack555.

The second guide plate5933may not extend throughout the longitudinal length of the guide body591, but may be formed only at a portion of the guide body591.

The second guide plate5933may restrict movement of the compressor55past the portion of the guide body591over which the second guide plate5933extends, thereby determining the quantity of impurities to be compressed by the filter assembly5via the second guide plate5933.

The impurities, separated from the filter533by the brush57, are moved by the compression plate551in a given direction from the air introduction hole5317(e.g., from the front side of the housing51) toward the air outlet133(e.g., toward the rear side of the housing51) located opposite to the air introduction hole5317until the impurities reach a position of the second guide plate5933.

Accordingly, the impurities within the housing51are compressed and stored in a rear space of the housing51corresponding to the length of the second guide plate5933by the compression plate551. The size of the rear space of the housing51corresponding to the length of the second guide plate5933may determine the maximum storage quantity of impurities of the filter assembly5(e.g., the maximum storage quantity of impurities to prevent deterioration of drying efficiency).

Whether or not the quantity of impurities within the housing51exceeds the predetermined maximum storage quantity is judged via a storage quantity sensing unit. This will be described later in more detail.

The compressor55, as shown inFIGS. 5(a) and 5(b), may further include a plurality of through-holes552perforated in the compression plate551. The through-holes552serve to reduce (e.g., prevent) reduction in flow rate due to the compression plate551.

Since the compression plate551is configured to reciprocate within the housing51, the compression plate551may prevent air, introduced into the housing51through the air introduction hole5317, from moving rearward of the housing51if the compression plate551is not provided with the through-holes552. Therefore, the air filtration capacity of the filter assembly5may be reduced by the compression plate551.

In addition, if the compression plate551has no through-holes552, the compression plate551may fail to implement normal reciprocation due to resistance of air introduced into the housing51, and may cause overload of the drive unit6.

The compression plate551may further be provided at opposite ends thereof with rack connection recesses553into which the first rack554and the second rack555are fitted respectively.

The brush57may have a plurality of brush bosses571arranged on an upper surface of the compression plate551.

In this case, the filter frame531may further be provided with a scraper535to separate impurities from the brush57.

The filter frame531may have a plurality of ribs5312configured to support the filter533. The scraper535may include a plurality of scraper bosses5351protruding from the ribs5312.

The plurality of brush bosses571may be arranged at a predetermined interval on the upper surface of the compression plate551. The respective brush bosses571may be arranged to pass each space between adjacent scraper bosses5351.

More specifically, the plurality of brush bosses571may be spaced apart from one another so as to pass each space between one scraper boss5351and another scraper boss5351when the brush57reciprocates within the storage space511.

This serves to prevent the brush bosses571from coming into contact with the scraper bosses5351and from hindering movement of the compression plate551when the compression plate551reciprocates within the storage space511.

In other examples in which the scraper bosses5351are configured to come into contact with the brush bosses571, in order to prevent the scraper bosses5351from hindering movement of the compressor55to the maximum extent, each scraper boss5351may have a scraper slope S (seeFIG. 4) formed at a side thereof facing the air introduction hole5317.

The compressor55and the brush57as described above are adapted to reciprocate within the storage space511by the drive unit6.

As shown inFIG. 6, the brush drive unit6may include a motor61(e.g., brush motor) secured to the exterior of the discharge duct43, a motor gear63located within the discharge duct43, and a rack gear65(seeFIG. 4) located in the rack gear receiving portion5315to enable rotation of the first and second racks554and555.

Although the motor61may be placed within the discharge duct43, providing the motor61at the exterior of the discharge duct43may be advantageous in terms of repair and maintenance.

In the case in which the motor61is secured to the exterior of the discharge duct43, the motor gear63may be coupled to a rotating shaft611of the motor61penetrating the discharge duct43.

The rack gear65may include a first rack gear651and a second rack gear653respectively received in a pair of rack gear receiving portions5315of the frame531. The first rack gear651and the second rack gear653may be connected to each other via a connection shaft655.

If a great quantity of impurities is stored in the storage space511or remains on the filter533, the compressor55or the brush57may be affected by large resistance during reciprocation thereof. Therefore, provision of only one rack gear may cause difficulty in removing the impurities from the filter533and compressing the removed impurities within the storage space511.

For example, as the first rack gear651and the second rack gear653are connected to each other via the connection shaft655, and the first rack gear651and the second rack gear653are respectively engaged with the first rack554and the second rack555, the drive unit6may stably transmit power to the brush57and the compressor55, even if only one of the first rack gear651and the second rack gear653is connected to the motor gear63.

As shown inFIGS. 3 and 6, a distance between the filter insertion hole191and the rack gears651and653may be less than a distance between the filter insertion hole191and the motor gear63.

This serves to allow one of the rack gears651and653to be separated from the motor gear63when the filter assembly5is retracted from the discharge duct43and to allow one of the rack gears651and653to be connected to the motor gear63when the filter assembly5is inserted into the discharge duct43.

The connection shaft655may function as a hinge shaft that rotatably connects the first frame5311and the second frame5313of the filter frame531to each other.

In this case, the user may remove impurities stored in the housing51by opening the second frame5313. Accordingly, as compared to the case in which the first frame5311and the second frame5313of the filter unit53are integrated with each other, it may be possible to more easily remove the impurities stored in the housing51.

The laundry treatment apparatus100may further include a storage quantity sensing unit that judges the quantity of impurities stored in the storage space511of the housing51.

The storage quantity sensing unit may have any configuration suitable to sense the quantity of impurities within the storage space511.

FIG. 7shows an example of a storage quantity sensing unit that is adapted to sense a position of the compressor55or the brush57upon operation of the drive unit6, thereby judging the quantity of impurities stored in the storage space511. The storage quantity sensing unit will hereinafter be referred to as a position sensing unit7.

The position sensing unit7may include a magnetism generator71provided at the compressor55or the brush57, and at least two magnetism sensors73and75adapted to sense a position of the magnetism generator71.

As shown inFIG. 7, if the magnetism generator71is provided at the compressor55, the magnetism sensors73and75may be fixed within the discharge duct43to sense the magnetism generator71through holes514and515perforated in a bottom surface of the housing51defining the storage space511.

The magnetism generator71may be a permanent magnet or an electromagnet. The magnetism sensors73and75may be reed switches that generate an ON-OFF control signal using magnetism provided by the magnetism generator71to transmit the control signal to the controller.

The magnetism sensors may include a first magnetism sensor73that senses whether or not the compressor55is located at a preset initial position (e.g., a first reciprocation threshold position L1of the compressor55), and a second magnetism sensor75that judges whether or not the storage quantity of impurities exceeds a preset storage quantity (e.g., whether or not the compressor55is movable to a second reciprocation threshold position L2).

The initial position may be set to any position within the housing51so long as the compressor55does not hinder flow of air introduced into the filter assembly5through the air introduction hole5317.FIG. 7shows the case in which the initial position is set to the front surface of the housing51(e.g., a surface of the housing51where the handle513is located, or a space between the air introduction hole5317and the handle513).

Once the filter assembly5is inserted into the discharge duct43, the first magnetism sensor73and the magnetism generator71may face each other through the first hole514perforated in the bottom surface of the housing51.

The second magnetism sensor75is positioned to judge the maximum quantity of impurities that may be stored in the housing51.

The maximum quantity of impurities that may be stored in the housing51may be set to a position where drying efficiency is deteriorated. If movement of the compressor55or the brush57is restricted by the second guide plate5933, the second magnetism sensor75may be located at the same position as a front edge of the second guide plate5933facing the air introduction hole5317.

Accordingly, the controller may check whether or not the first magnetism sensor73senses the magnetism generator71before operation of the laundry treatment apparatus100, thereby checking whether or not the brush57or the compressor55is located at an initial position and whether or not the filter assembly5is mounted in the discharge duct43.

In addition, the controller may check whether or not the second magnetism sensor75senses the magnetism generator71, thereby judging a removal time of impurities stored in the filter assembly5.

Accordingly, the controller may request that the user remove impurities stored in the filter assembly5(e.g., stop operation of the rotating shaft611of the motor61) via an alarm device (e.g., a display device and/or a speaker) if the second magnetism sensor75does not sense the magnetism generator71.

In the case of the filter assembly5having the above-described configuration, if the compressor55reciprocates within the housing51between the first reciprocation threshold position L1and the second reciprocation threshold position L2, the racks554and555may be exposed to the outside of the housing51.

This may restrict the size of the filter assembly5that is separably placed within the discharge duct43. Therefore, the filter assembly5may further include a rack retraction preventing member517.

Referring toFIGS. 8(a) and 8(b), the rack retraction preventing member517is placed within the housing51and serves to prevent the racks554and555from being exposed to the outside of the housing51when the compressor55is moved to the second reciprocation threshold position L2.

More specifically, a pair of rack retraction preventing members517is provided respectively at opposite sides of the housing51to move the first rack554and the second rack555forward of the housing51after the first rack554and the second rack555are moved rearward of the housing51.

To this end, the rack guide59may further include body through-holes (595, seeFIG. 4) perforated in the guide body591for connection of the rack retraction preventing members517.

The rack retraction preventing member517, as shown inFIG. 8, may include a semicircular portion extending from the top to the bottom of the housing51, and a linear portion extending from a lower end of the semicircular portion to the top of the housing51(seeFIG. 8(a)).

Note that the linear portion may extend parallel to the bottom surface of the housing51toward the front surface of the housing51(seeFIG. 8(b)).

Further, the filter assembly5is separable from the discharge duct43, and thus may be moved within the discharge duct43during operation of the drive unit6.

As the rack gear65disposed on the filter assembly5is engaged with the motor gear63located within the discharge duct43, the impurity remover unit B may be moved within the housing51.

Accordingly, the filter assembly5provided with the rack gear65may be moved upward and downward within the discharge duct43during rotation of the motor gear63. Such movement of the filter assembly5within the discharge duct43may cause separation between the motor gear63and the rack gear65as well as generation of noise.

To address these issues, the laundry treatment apparatus100may further include a filter guide433configured to restrict (e.g., prevent) movement of the filter assembly5inserted in the discharge duct43.

As shown inFIG. 9, the filter guide433may be placed within the discharge duct43to support an upper surface of the filter assembly5.

The filter assembly5may further include a frame guide536protruding from an upper surface of the filter frame531to extend in a longitudinal direction of the filter frame531(e.g., in a longitudinal direction of the discharge duct43), and a guide slope5361formed at the frame guide536to connect an upper surface of the frame guide536and the upper surface of the filter frame531to each other.

In this case, the filter guide433may include a first guide4331configured to come into contact with the guide slope5361, and a second guide4333configured to come into contact with the upper surface of the filter frame531.

The first guide4331serves to prevent the filter assembly5from being moved rearward of the discharge duct43during rotation of the motor gear63, and the second guide4333serves to restrict (e.g., prevent) the filter assembly5from being separated from the bottom surface of the discharge duct43during rotation of the motor gear63.

In addition, the discharge duct43may be provided with the path guide431configured to guide air discharged from the connection duct41to the air introduction hole5317of the filter frame531.

The path guide431extends from the bottom of the duct connection hole435of the discharge duct43toward the filter frame531. The path guide431may be configured to come into contact with the frame guide536.

This serves to allow the path guide431to restrict (e.g., prevent) the front surface of the filter assembly5from being separated from the bottom surface of the discharge duct43during rotation of the motor gear63.

FIGS. 10 to 13illustrate another example filter assembly included in the laundry treatment apparatus100.

The filter assembly5, as shown inFIG. 11, includes the housing51having the storage space511in which impurities are stored and the handle513, a filter unit52disposed on the housing51to filter air to be moved from the interior of the housing51to the outside of the housing51(e.g., to the discharge duct43), and the impurity remover unit B placed within the housing51(e.g., within the storage space511) to separate impurities remaining on the filter unit52and compress the impurities separated from the filter unit52within the housing51.

The filter unit52includes a filter frame521secured to the housing51, and a filter523secured to the filter frame521to filter air.

The filter frame521is configured to receive an upper surface and both lateral surfaces of the housing51. The filter frame521includes a first frame5211and a second frame5212to which the filter523is secured.

The first frame5211and the second frame5212are located at the open upper side of the housing51. The second frame5212is rotatably coupled to the filter frame521and is separable from the housing51.

Both the first frame5211and the second frame5212have holes to which the filter523is secured. A grid type rib (5213, filter support rib) is provided at the holes to support the filter523.

The first frame5211has an air introduction hole5214, through which air introduced into the discharge duct43is moved into the housing51.

Accordingly, the air, introduced into the discharge duct43through the connection duct41, is moved into the housing51through the air introduction hole5214by way of the path guide431. Then, the air inside the housing51is filtered by the filter523while moving to the discharge duct43.

The impurity remover unit B may include the compressor55placed within the housing51to compress impurities within the housing51, and the brush57disposed on the compressor55to separate impurities remaining on the filter523from the filter523.

The compressor55may include the compression plate551configured to reciprocate within the housing51via operation of the drive unit6, and the plurality of through-holes552perforated in the compression plate551.

In this case, the brush57may have the plurality of brush bosses571arranged on the upper surface of the compression plate551and spaced apart from one another by a predetermined distance.

The rib5213of the filter frame521may be provided with a scraper525. The scraper525may serve to separate impurities from the brush bosses571and assist in moving the impurities into the storage space511of the housing51.

The scraper525, as shown inFIG. 10, may have a plurality of scraper bosses5251, which are formed at the rib5213and spaced apart from one another by a predetermined distance in a width direction of the housing51.

The position relationship of the scraper bosses5251and the brush bosses571and the shape of the scraper bosses5251have been described above, and thus a detailed description thereof will be referenced, rather than repeated.

In some examples, two cover frames5215are provided at opposite ends of the filter frame521to receive opposite longitudinal surfaces of the housing51.

Each of the cover frames5215has a connection plate slit5216perforated therein in a longitudinal direction of the housing51. A cover5218is secured to the cover frame5215to define a predetermined space between the cover5218and the cover frame5215.

Accordingly, the cover5218serves to prevent the connection plate slit5216from being exposed to the outside.

The connection plate slit5216serves to allow a rack connection plate683or693, which serves to transmit power of the drive unit6to the compression plate551, to penetrate the cover frame5215. This will be described later in more detail.

The cover frame5215has a frame slope5217formed at an upper surface thereof. With provision of the frame slope5217, a rear portion of the upper surface of the cover frame5215has a lower height than that of a front portion of the upper surface.

The filter guide433located within the discharge duct43is coupled to the frame slope5217and the rear portion of the upper surface of the cover frame5215. This coupling restricts (e.g., prevents) the filter assembly5from being moved within the discharge duct43during operation of the drive unit6. Functions of the frame slope5217and the filter guide433have been described above with reference toFIG. 9, and thus a detailed description thereof will be referenced, rather than repeated.

The impurity remover unit B is adapted to reciprocate within the housing51upon receiving power from the drive unit6. Hereinafter, a configuration of the drive unit6will be described with reference toFIG. 11.

The drive unit6may include the motor61located at the exterior of the discharge duct43, a motor gear63coupled to the rotating shaft611of the motor61and located within the discharge duct43, a separable gear62rotatably secured to the cover5218and separably engaged with the motor gear63, a first intermediate gear641located between the cover frame5215and the cover5218and connected to the separable gear62, a first rack68located between the cover frame5215and the cover5218and connected to the compression plate551, and a first rack gear651configured to connect the first rack68and the first intermediate gear641to each other.

The motor61, as shown inFIG. 13, is secured to the exterior of the discharge duct43. The rotating shaft611of the motor61penetrates the discharge duct43and is coupled to the motor gear63located within the discharge duct43.

A separable gear rotating shaft621coupled to the separable gear62, as shown inFIG. 11, penetrates the cover5218and is coupled to the first intermediate gear641. The first intermediate gear641is connected to the first rack68via the first rack gear651that is rotatably coupled to the cover frame5215.

Accordingly, once the filter assembly5is inserted into the discharge duct43, the separable gear62is engaged with the motor gear63to enable transmission of power from the motor61to the first rack68.

Note that the first rack gear651may be omitted if the first intermediate gear641is directly engaged with the first rack68.

To ensure that the compression plate551stably reciprocates within the housing51, the drive unit6may further include a second rack69which is located between the cover frame5215and the cover5218and is secured to the compression plate551.

In this case, the drive unit6may further include a second intermediate gear643connected to the first intermediate gear641via a connection gear, and a second rack gear653configured to connect the second intermediate gear643and the second rack69to each other.

The connection gear may include a first connection gear671which is provided at the cover frame5215and is coupled to the first intermediate gear641, and a second connection gear673which is coupled to the first connection gear671via a connection shaft677and is coupled to the second intermediate gear643.

The connection shaft677may be arranged in a width direction of the housing51and may penetrate both the cover frames5215provided respectively at opposite ends of the filter frame521.

Accordingly, the connection shaft677may serve not only to connect the first connection gear671and the second connection gear673to each other, but also to rotatably secure the second frame5212to both the cover frames5215.

The first connection gear671and the second connection gear673may be rotatably arranged above the first and second intermediate gears641and643respectively, and the first rack gear651and the second rack gear653may be rotatably secured to the respective cover frames5215and located below the first and second intermediate gears641and643respectively.

The first rack68and the second rack69are respectively secured to opposite ends of the compression plate551via the connection plates683and693penetrating the connection plate slits5216. The first rack68and the second rack69are moved in a space between the cover frame5215and the cover5218via operation of the motor61, which allows the impurity remover unit B to reciprocate within the housing51.

The first rack68includes a first rack body681in the form of a bar, a first geared portion685formed at a surface of the first rack body681and engaged with the first rack gear651, and the first connection plate683formed at the first rack body681and inserted into the connection plate slit5216to thereby be secured to the compression plate551. The first geared portion685is located only at a partial region of the first rack body681.

The second rack69includes a second rack body691in the form of a bar, the second connection plate693formed at the second rack body691and inserted into the connection plate slit5216to thereby be secured to the compression plate551, and a second gear portion695located only at a partial region of the second rack body691and engaged with the second rack gear653.

In this case, the cover frame5215may further include a rack guide5219configured to guide movement of the rack68or69.

As shown inFIGS. 12(a) to (c), the rack guide5219may include a rack body receiving portion G2in which the rack body681or691is received, and a gear receiving portion G1in which the geared portion685or695is received, the gear receiving portion G1extending from the rack body receiving portion G2.

In this case, the rack body receiving portion G2may be located below the connection plate slit5216(e.g., at a position spaced apart from the connection plate slit5216by a distance equal to or less than the thickness of the rack body681or691) to ensure that the connection plate slit5216is covered by the rack body681or691when the compression plate551reciprocates within the housing51.

This arrangement may reduce malfunction of the drive unit6caused when impurities within the housing51are moved to the cover frame5215through the connection plate slit5216.

As described above, since the connection plate slit5216is perforated in the cover frame5215, there is risk of impurities within the housing51being moved to the cover frame5215through the connection plate slit5216in a state in which the connection plate slit5216is open, thereby preventing rotation of the gears641,643,651,653,671, and673.

However, the filter assembly5may address this issue as the rack body681or691closes the connection plate slit5216regardless of a position of the compression plate551within the housing51.

More specifically, the rack body681or691may be divided into a front body6811or6911and a rear body6813or6913on the basis of the connection plate683or693, and the length of the front body6811or6911may be greater than the length of the connection plate slit5216.

The rack body receiving portion G2extends from a lower portion of the cover frame5215to an upper portion of the cover frame5215where the connection plate slit5216is formed. An end of the rack body receiving portion G2located in the lower portion of the cover frame5215is connected to the gear receiving portion G1.

The gear receiving portion G1extends from the lower portion of the cover frame5215to the upper portion of the cover frame5215. The rack gear651or653is located at the junction of the gear receiving portion G1and the rack receiving portion G2.

In addition, a rack body support portion G3configured to support an upper surface of the rack body681or691may further be formed within the rack body receiving portion G2.

As shown, the rack body681or691is moved in the rack body receiving portion G2as the geared portion685or695is engaged with the rack gear651or653. In this case, the rack body681or691may bend in the rack body receiving portion G2, thus blocking the rack body receiving portion G2due to a height difference between the rack body681or691and the geared portion685or695.

The rack body support portion G3serves to address this issue.

To this end, the geared portion685or695may be spaced apart from one end of the rack body681or691by a distance equal to the length of the rack body support portion G3.

That is, a width L3of the geared portion685or695may be less than a width L4of the rack body681or691, in order to prevent the geared portion685or695from interfering the rack body support portion G3even if the geared portion685or695is moved into the rack body receiving portion G2.

Moreover, a partial region of a space provided by the gear receiving portion G1where the rack gear651or653is located may have the same height as that of the geared portion685or695, but the remaining region of the space may have a greater height that that of the geared portion685or695.

The geared portion685or695is engaged with the rack gear651or653in a connection region of the gear receiving portion G1and the rack body receiving portion G2because minimizing interference between the geared portion685or695and the gear receiving portion G1in the remaining region may be advantageous in terms of movement of the rack68or69.

The position sensing unit may be provided to measure the quantity of impurities stored in the housing51.

The position sensing unit may include the magnetism generator secured to the compression plate551, the first magnetism sensor secured within the discharge duct43at the first reciprocation threshold position L1, and the second first magnetism sensor secured within the discharge duct43at the second reciprocation threshold position L2,

In this case, the housing51may further have the first hole perforated in the housing51defining the storage space511to allow the first magnetism sensor to sense the magnetism generator and the second hole formed to allow the second magnetism sensor to sense the magnetism generator.

FIGS. 14 and 15illustrate another example filter assembly included in the laundry treatment apparatus.

The filter assembly5includes the housing51in which impurities are stored, the housing51being separable from the discharge duct43through the filter insertion hole191of the filter support panel19, the filter unit53configured to filter air introduced into the housing51, and an impurity remover unit58rotatably placed within the housing51, the impurity remover unit58serving to remove impurities from the filter unit53and to compress the impurities separated from the filter unit53within the housing51.

As shown inFIG. 15, the housing51may be a hexahedral housing defining a storage space. The handle513is provided at the front surface of the housing51, and the air introduction hole512is formed in the upper surface of the housing51such that air introduced into the discharge duct43is moved into the housing51through the air introduction hole512.

A plurality of housing through-holes520is formed in the upper surface and the bottom surface of the housing51to communicate the interior of the housing51with the exterior of the housing51(e.g., the interior of the discharge duct43). The filter unit53is secured to the housing through-holes520.

A plurality of filter support ribs516configured to support the filter unit53may be provided at the housing through-holes520.

The impurity remover unit58may include a brush frame581rotatably secured within the housing51via a brush rotating shaft585, and a brush583provided at an outer peripheral surface of the brush frame581to come into contact with the filter unit53.

The brush583may have a plurality of bosses (e.g., brush bosses) protruding from the outer peripheral surface of the brush frame581to come into contact with the filter unit53. Accordingly, the brush583may separate impurities remaining on the filter unit53from a surface of the filter unit53during rotation of the brush frame581.

In this case, the filter support rib516may be provided with a scraper518, which comes into contact with the brush583to separate impurities from the brush583during rotation of the brush frame581.

The scraper518may have a plurality of bosses (e.g., scraper bosses) protruding from the filter support rib516. The respective brush bosses may be arranged to pass each space between adjacent scraper bosses.

The brush frame581is rotated within the housing51by the drive unit6that is provided at the exterior of the housing51. The drive unit6may include the motor61secured to the discharge duct43and the gear66configured to transmit power of the motor61to the brush frame581.

The motor61may be secured to the exterior of the discharge duct43. In this case, a rotating shaft of the motor61may penetrate the discharge duct43.

The gear66, as shown inFIG. 14, may include a driving gear661(e.g., motor gear) secured to the rotating shaft of the motor61and located within the discharge duct43, and a driven gear663coupled to the brush rotating shaft585and located at the outside of the housing51.

Accordingly, if the controller operates the motor61, the driving gear661and the driven gear663are rotated, and the brush frame581secured to the brush rotating shaft585is rotated within the housing51via rotation of the driven gear663.

Note that the controller may rotate the motor61forward or in reverse to allow the brush frame581to reciprocate over a predetermined interior region of the housing51.

If the brush frame581reciprocates within the housing51, the brush583may separate impurities from the surface of the filter unit53. The impurities separated from the surface of the filter unit53may be compressed in one side of the housing51by the brush frame581.

In addition, a gear receiving recess519in which the driving gear661and the driven gear663are received may further be formed in the outer peripheral surface of the housing51. The gear receiving recess519serves to prevent the gear66from protruding from the outer peripheral surface of the housing51, thereby protecting the gear66when the filter assembly5is inserted into or retracted from the discharge duct43.

As is apparent from the above description, a laundry treatment apparatus may increase the filtration capacity of a filter.

Further, a laundry treatment apparatus may provide a configuration to increase the quantity of hot air to be supplied into a drum in which laundry is received and to increase the filtration capacity of a filter, thereby being usable as a commercial drying machine.

Furthermore, a laundry treatment apparatus may judge whether or not a filter is mounted in the laundry treatment apparatus and judge the quantity of impurities remaining on the filter.

In addition, a laundry treatment apparatus may inform a user of a cleaning time of a filter based on the quantity of impurities remaining on the filter.

It will be apparent that, although examples have been shown and described above, the disclosure is not limited to the above-described examples, and various modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the appended claims. Thus, it is intended that the modifications and variations are part of the disclosure and covered by the appended claims.