Abstract:
A wet-type dust collector for a vacuum cleaner. The disclosed wet-type dust collector includes a first separating portion, the inside of which is filled with water for separating dust from air that is suctioned in from the outside; an exhaust pipe unit having an exhaust outlet and installed inside the first separating portion; and a passage-closing unit installed inside the exhaust pipe unit, wherein the passage-closing unit closes the exhaust outlet of the exhaust pipe unit by means of the combined forces of the suctioning force through the exhaust pipe unit and the buoyant force of the water, in order to prevent the water from leaking out from the first separating portion.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a U.S. National Phase application of PCT/KR2010/004009 filed Jun. 21, 2010 and claims the priority benefit of Korean Application No. 10-2009-0079416 filed Aug. 26, 2009 in the Korean Intellectual Property Office, the contents of both of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    The invention relates to a wet-type dust collector for a vacuum cleaner which collects dust using water, and more particularly, to a wet-type dust collector for a vacuum cleaner which is capable of efficiently preventing leakage of water filled in the wet-type dust collector. 
         [0004]    2. Description of the Related Art 
         [0005]    Generally, a vacuum cleaner, which operates to separate dust using centrifugal force, and a wet-type dust collector with improved dust separating efficiency, filling an interior of a dust bin with water and collecting dust using the water, has been distributed. 
         [0006]    A conventional wet-type dust collector may have an increasingly contaminated interior due to foreign matters combined with water when the water of the dust bin is discharged outside the wet-type dust collector through an exhaust outlet of the dust bin, possibly resulting in hygienic problems. Further, if the water leaks inside the vacuum cleaner and enters the fan motor unit, the interior of the fan motor unit may be corroded and moisture or water may overflow outside the vacuum cleaner. 
         [0007]    Accordingly, various constructions have been suggested to prevent the leakage of the water of the dust bin of a wet-type dust collector into the vacuum cleaner. 
         [0008]    One of such examples is disclosed in Japanese Patent Publication No. 2002-102124 (‘Conventional art 1’), Japanese Patent No. 3291377 (‘Conventional art 2’), and Korean Patent Publication No. 2006-0101060 (‘Conventional art 3’). 
         [0009]    Conventional art 1 discloses a wet-type dust collector constructed such that a floater is provided inside a dust bin to close an exhaust outlet of a dust bin by rising in accordance with the rise of the water level. 
         [0010]    Conventional art 2 discloses a vacuum cleaner in which a pre-filter with a floater accommodated in a fluid communicating port thereof is connected to a fan motor unit so that the floater closes the fluid communicating port as the level of water rises in the water tank. 
         [0011]    Conventional art 3 discloses a wet-type dust collector in which a floater is arranged inside a filter installed at an exhaust outlet of a dust bin, to close the exhaust outlet by rising in response to the introduction of water into the filter. 
         [0012]    As explained above, the conventional arts prevent the leakage of water into the vacuum cleaner by using a floater which floats on water and rises in accordance with the increasing water level as the water is over-charged in the dust bin or the like. 
         [0013]    However, since the conventional arts are constructed to close the exhaust outlet of the dust bin by the floater which rises in accordance with the water level, reliability of preventing water leakage into the vacuum cleaner deteriorates. That is, if water shakes while the vacuum cleaner is driven, the floater alone cannot prevent the leakage of water through the exhaust outlet efficiently. Further, if water drops (droplets) are generated from the water, it is impossible to prevent leakage of such droplets in the exhausted air to outside of the wet-type dust collector. 
         [0014]    Further, in conventional arts 2 and 3 in which the floater is arranged inside a vertical exhaust pipe of a centrifuging portion, the suction force at the upper portion of the exhaust pipe is directly transmitted to the surface of the water on which the floater is positioned. Accordingly, the water shakes can occur by the suction force on the surface of the water on which the floater is positioned. In this case, if the droplets are generated by the water shakes, it is impossible to prevent leakage of the generated droplets to outside of the wet type dust collector due to the suction force. 
         [0015]    Further, although the water of the dust collecting device such as dust bin or water tank is at such a level that does not cause the floater to close the exhaust outlet, at high water level, water can be discharged out of the wet-type dust collector due to suction force generated in the driving of the vacuum cleaner, and leaked into the vacuum cleaner. 
         [0016]    In order to overcome the above-mentioned problems in the conventional arts, an object of the following disclosure is to provide a wet-type dust collector for use in a vacuum cleaner which is capable of efficiently preventing leakage of water filled in the wet-type dust collector. 
         [0017]    Further, another object of the invention is to provide a wet-type dust collector for use in a vacuum cleaner in which shaking of water filling in the wet-type dust collector due to suction force during operation of the vacuum cleaner, or leakage of the water along an exhaust pipe unit in a slip stream of the dust collector, is prevented. 
       SUMMARY 
       [0018]    Additional aspects and/or advantages will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the invention. 
         [0019]    In order to achieve the above-mentioned objects, a wet-type dust collector includes: a first separating portion, the inside of which is filled with water for separating dust from air that is suctioned in from the outside; an exhaust pipe unit having an exhaust outlet and installed inside the first separating portion; and a passage-closing unit installed inside the exhaust pipe unit, wherein the passage-closing unit closes the exhaust outlet of the exhaust pipe unit by means of the combined forces of the suctioning force through the exhaust pipe unit and the buoyant force of the water, in order to prevent the water from leaking out from the first separating portion. 
         [0020]    The passage-closing unit may include a closing plate mounted inside the grill to be moveable upward and downward, a floater installed inside the exhaust pipe unit, and a closing plate support rod which connects the floater and the closing plate. 
         [0021]    A rod insertion hole may be formed in the floater, and the closing plate support rod may be inserted into the rod insertion hole to be moveable upward and downward. 
         [0022]    The closing plate support rod may include a length so that a lower end is not separated from the rod insertion hole when the closing plate closes the exhaust outlet of the exhaust pipe unit. 
         [0023]    When the water level is above a normal level, but not at a location to allow the closing plate to close the exhaust outlet, the closing plate may be raised by the suction force of the vacuum cleaner to close the exhaust outlet when the vacuum cleaner is driven. 
         [0024]    The passage-closing unit may be constructed to close the exhaust outlet of the exhaust pipe unit by the suction force transmitted through the exhaust pipe unit, if the water level is above a normal level. 
         [0025]    The exhaust pipe unit may additionally include a locking jaw positioned on a lower portion of the grill to restrict upward and downward movement of the passage-closing unit; and a plurality of water inlets pierced through the exhaust pipe unit, and may be installed in the first separating portion in such a manner that an upper end of the exhaust pipe unit is in fluid communication with outside, and a lower end is submerged in water filled in the wet-type dust collecting region. 
         [0026]    The wet-type dust collector may additionally include a second separating portion to separate dust particles entrained in air discharged from the first separating portion with water filled inside. 
         [0027]    The second separating portion may additionally include a plurality of second introducing pipe units formed on a side surface of the first separating portion. 
         [0028]    In order to achieve the above-mentioned objects, a wet-type dust collector includes: a first separating portion, filled with water, to separate dust from air that is suctioned in from outside; an exhaust pipe unit having an exhaust outlet and installed inside the first separating portion to pass air; and a passage-closing unit installed inside the exhaust pipe unit to prevent the ingress of water, wherein the passage-closing unit comprises a closing plate mounted inside a grill to be moveable upward and downward to prevent the ingress of water, based on a combined suction force. 
         [0029]    In order to achieve the above-mentioned objects, a wet-type dust collector may also include an apparatus to prevent water leakage, including: an inlet to pass external air into the apparatus by suctioning; a first separating portion, filled with water, to separate dust from the external air; an exhaust pipe unit having an exhaust outlet and installed inside the first separating portion to pass air out of the apparatus; and a passage-closing unit installed inside the exhaust pipe unit to prevent the ingress of water, wherein the passage-closing unit comprises a closing plate mounted inside a grill to be moveable upward and downward to prevent the ingress of water, based on a combined suction force. 
         [0030]    According to the present disclosure described above, if the level of the water filled in the wet-type dust collector exceeds a predetermined level, since the closing plate closes the exhaust pipe unit, water leakage to outside is prevented. 
         [0031]    Further, according to the present disclosure, since the closing plate in normal water level closes the closing plate support rod moving hole formed in the lower portion of the grill of the exhaust pipe unit, transmission of suction force through the exhaust pipe unit is blocked, and as a result, water shaking due to suction force or rising through the exhaust pipe unit and leaking outside are prevented. 
         [0032]    Further, according to the present invention, even when the closing plate is at high water level that does not close the exhaust pipe unit, since the closing plate is risen by the suction force to close the exhaust pipe unit as the vacuum cleaner is driven to generate suction force, water leakage to outside is prevented. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0033]    The above features and/or other aspects and advantages will become apparent and more readily appreciated from the following description of the embodiments taken in conjunction with the accompanying drawings in which: 
           [0034]      FIG. 1  is a perspective view of a wet-type dust collector  1 , according to an example embodiment; 
           [0035]      FIG. 2  is a cross-section view of the wet-type dust collector  1  taken along line II-II of  FIG. 1 ; 
           [0036]      FIG. 3  is a front view of a grill  211 ′, according to a modified embodiment; 
           [0037]      FIG. 4  is a cross-section view taken along line II-II of the wet-type dust collector  1  of  FIG. 1 , illustrating water filling up to the level that causes a closing plate  701  to be positioned between the exhaust outlet  212  and a closing plate support rod moving hole  211   d;  and 
           [0038]      FIG. 5  is a cross-section view taken along line II-II of the wet-type dust collector  1  of  FIG. 1 , illustrating a state in which the closing plate  701  closes the exhaust outlet  212 . 
       
    
    
     DETAILED DESCRIPTION 
       [0039]    Reference will now be made in detail to the embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below to explain the present disclosure by referring to the figures. 
         [0040]      FIG. 1  is a perspective view of a wet-type dust collector according to an embodiment, and  FIG. 2  is a cross-section view taken along line II-II of  FIG. 1 . 
         [0041]    The wet-type dust collector  1  includes a centrifugal separating assembly  200  and a dust bin unit  300 . 
         [0042]    The centrifugal separating assembly  200  (referring to  FIG. 2 ) includes a handle unit  100 , a first inlet  201 , an exhaust chamber  270 , a partitioning wall  250  which defines a second passage  240  at an upper portion of the dust bin unit  300 , a first centrifugal separating region  200   c  at a lower portion, and a plurality of second centrifugal separating regions  210   c,  a first centrifugal separating pipe  200   a,  a first exhaust pipe unit  210 , a passage-closing unit  700 , a plurality of second centrifugal separating pipes  210   a  in fluid communication with the exhaust chamber  270 , and a plurality of second introducing pipe units  230 . 
         [0043]    The handle unit  100  is formed on the centrifugal separating assembly  200  and constructed for carrying of the centrifugal separating assembly  200 , or to fix or separate the centrifugal separating assembly  200  to or from the dust bin unit  300 . If the handle unit  100  is in a position to firmly fix the connection between the centrifugal separating assembly  200  and the dust bin unit  300 , a grip portion  101  is fixed in position so as not to be rotated by a holder  150 . 
         [0044]    The first inlet  201  is formed on a side surface of the centrifugal separating assembly  200  to pass the external air from a brush assembly (not illustrated) of the like of the vacuum cleaner into the first centrifugal separating region  200   c.    
         [0045]    The exhaust chamber  270  is formed such that the second exhaust outlets  252  are all placed inside on one side surface of the centrifugal separating assembly  200  which the second exhaust outlets  252  exhausting air from the second centrifugal separating pipes  210   a  are formed. According to the construction explained above, the exhaust chamber  270  combines the exhaust air from the second exhaust outlets  252  and exhausts the air to a fan motor unit (not illustrated) of the vacuum cleaner (not illustrated). 
         [0046]    The partitioning wall  250  includes, formed on a lower surface thereof, a first exhaust outlet  202  in fluid communication with the first exhaust pipe unit  210  and a plurality of second inlets  231  in fluid communication with the plurality of second introducing pipe units  230 . The partitioning wall  250  is placed transversely on an inner side of the upper portion of the centrifugal separating assembly  200  to separate the area of the centrifugal separating assembly  200  into the second passage  240  at the upper portion and the first centrifugal separating region  200   c  at the lower portion, and the plurality of second centrifugal separating regions  210   c.  The second passage  240  formed by the partitioning wall  250  passes the air exhausted from the first exhaust outlet  202  to the plurality of second centrifugal separating regions  210   c  through the plurality of second inlets  231  and the second introducing pipe units  230 . 
         [0047]    The first centrifugal separating pipe  200   a  defines the first centrifugal separating region  200   c  at which larger and heavier dust particles are separated from the external air introduced through the first inlet  201 . The first centrifugal separating pipe  200   a  may be formed into various shapes to have rectangular, trapezoidal or inverted trapezoidal cross-section. 
         [0048]    The first centrifugal separating pipe  200   a  with the above-explained structure is installed on a lower surface of the partitioning wall  250  so that the upper portion is kept in fluid communication with the first exhaust outlet  202 . 
         [0049]    The first exhaust pipe unit  210  is an embodiment of the exhaust pipe unit according to the prevent disclosure, which is formed as a cylindrical pipe that includes a guide  203 , a grill  211  and a sealing member  220 . 
         [0050]    The guide  203  protrudes in a spiral pattern on the upper and outer circumferential surface of the first exhaust pipe unit  210  to induce rotation of the introduced air. 
         [0051]    The grill  211  has a structure in which a plurality of exhaust holes  211   a  are formed to filter out foreign matters entrained in the air exhausted through the first exhaust pipe unit  210 . The grill  211  is formed at a center portion of the first exhaust pipe unit  210 . The upper area of the grill  211  becomes the exhaust outlet  212 , while the lower area thereof becomes the closing plate support rod moving hole  211   d.    FIG. 3  is a front view of the grill  211 ′ according to a modified embodiment, in which the grill  211 ′ has a plurality of grill ribs  211   c  protruding from the circumferential surface at a predetermined angle to form the exhaust outlets  211   a′.    
         [0052]    The sealing member  220  is attached to a lower surface of the first exhaust pipe unit  210 . 
         [0053]    Further, on an inner circumferential surface of the first exhaust pipe unit  210  that forms the lower surface of the grill  211 , a locking jaw  211   b  extends to the direction of center so that the central portion forms the closing plate support rod moving hole  211   d.    
         [0054]    The first exhaust pipe unit  210  with the above-explained structure is connected to the centrifugal separating assembly  200  by being attached to the lower surface of the partitioning wall  250  in a fluid communication with the second passage  240  through the first exhaust outlet  202  inside the first centrifugal separating pipe  200   a.    
         [0055]    As the centrifugal separating assembly  200  with the first exhaust pipe unit  210  connected thereto is connected to the dust bin unit  300 , the sealing member  220  is engaged with a water distributing hole  501  of the water distributing passage portion  500 . Accordingly, the water distributing passage portion  500  and the first wet-type dust collecting region  300   c  are isolated from each other due to the presence of the sealing member  220 . 
         [0056]    The passage-closing unit  700  is installed inside the first exhaust pipe unit  210  to prevent the ingress of water W into the vacuum cleaner (not illustrated) through the first exhaust pipe unit  210 . 
         [0057]    The passage-closing unit  700  includes a closing plate  701 , a floater  703  and a closing plate support rod  702  which connects the closing plate  701  with the floater  703 . 
         [0058]    The closing plate  701  is formed into a shape corresponding to the cross-section of the inner circumference of the first exhaust pipe unit  210  to seal off the internal passage of the grill and the exhaust outlet  212 . The closing plate  701  is moveable upward and downward inside the grill  211 . 
         [0059]    The floater  703  is installed inside the first exhaust pipe unit  210  at which the water introducing hole  213  is formed. On an outer circumferential surface of the lower end of the first exhaust pipe unit  210  at which the water introducing hole  213  is formed, a net  214  in a mesh structure is attached to prevent ingress of relatively larger particles of foreign matters through the plurality of water introducing holes  213 . The floater  703  is moveable upward and downward due to the buoyant force of the water W filling in the first dust bin  300   a.    
         [0060]    The closing plate support rod  702  is inserted into a rod insertion hole  752  of the floater  703  to be moveable upward and downward. When the cleaner is not in operation or the water level is low so that the closing plate is in a low position as illustrated in  FIG. 2  (‘normal, or below normal water level’), bottom of the closing plate support rod  702  is brought into contact with the lower surface of the rod insertion hole  752  of the floater due to the self gravity of the closing plate support rod  702 . Then as the closing plate  701  rises to above the central portion of the grill  211  as illustrated in  FIG. 4  (‘above normal water level’) and the cleaner is operated, the closing plate  701  and the closing plate support rod  702  are lifted due to the suction force to the state illustrated in  FIG. 5 . (This will be explained in greater detail below.) 
         [0061]    Further, the closing plate support rod  702  has a predetermined length so that the floater  703  and the closing plate  701  are moved upward and downward at a predetermined distance from each other. The length of the closing plate support rod  702  is kept within a range that does not allow separation of the closing plate  701  from the rod insertion hole  752  when in a state of closing the exhaust outlet  212 . That is, the closing plate support rod  702  has the length such that, when the closing plate  701  is drawn out of the floater  703  and extended due to the suction force, the lower end does not separate from the rod insertion hole  752  irrespective of where the floater  703  is located. Further, the closing plate support rod  702  may have varying length depending on the height, width and degree of suction force of the first dust bin  300   a,  and has an optimum length that is confirmed through experiments as not causing water overflow. 
         [0062]    Due to the distance between the floater  703  and the closing plate  701 , i.e., due to the closing plate support rod  702 , unlike the prior art, even when the water level of the first dust bin does not enable the floater  703  to seal off the exhaust outlet  212 , water overflow or leakage through the exhaust outlet  212  can be effectively prevented due to the presence of the closing plate  701 . 
         [0063]    The plurality of second centrifugal separating pipes  210   a  each has a cylindrical shape. On an upper surface of the second centrifugal separating pipes  210   a  is formed a second exhaust outlet  252  in fluid communication with the exhaust chamber  270 . Further, the plurality of second centrifugal separating pipes  210   a  has an inner diameter smaller than that of the first centrifugal separating pipe  200   a  to filter out minute dusts that are not removed in the first centrifugal separating pipe  200   a.    
         [0064]    Each of the second centrifugal separating pipes  210   a  with the above-explained structure is engaged with the lower surface of the partitioning wall  250 , to accommodate therein the second inlets  231 . When engaged as explained above, the second centrifugal separating pipes  210   a  define the second centrifugal separating regions  210   c.    
         [0065]    The plurality of second centrifugal separating pipes  210   a  are arranged on a side surface of the first centrifugal separating pipe  200   a,  in parallel, and integrated by the fluid communication with each other through the second passage  240 . 
         [0066]    The second introducing pipe unit  230  is formed in the shape of a cylindrical pipe with upper and lower open portions. On the lower end area of the second introducing pipe unit  230 , an impeller  235   a  is formed. The impeller  235   a  has a plurality of passing holes and an impeller rib  235   a  bent at a predetermined angle. The second introducing pipe unit  230  is connected to a lower surface of the partitioning wall  250  to be in fluid communication with the second passage  240  through the second inlet  231  inside each of the second centrifugal separating regions  210   c . The impeller  235  is submerged in water W in the second centrifugal separating regions  210   c . The impeller  235  causes the air discharged through the second introducing pipe unit  230  to be discharged in a circular motion around the second introducing pipe unit  230 . Accordingly, the air of the second centrifugal separating regions  210   c  and the water W of the second wet-type dust collecting region  310   c  are rotated. 
         [0067]    The dust bin unit  300  (see  FIG. 2 ) includes a first dust bin  300   a,  a plurality of second dust bins  310   a,  and a lower cover  400  which defines a water distributing passage portion  500  to connect lower portions of the first dust bin  300   a  and the second dust bins  310   a  in a fluid communication with each other, 
         [0068]    The first dust bin  300   a  defines a first wet-type dust collecting region  300   c  at which dust is collected due to the rotating water W. The first dust bin  300   a  may have a variety of cross-sections including rectangle, trapezoid or inverted trapezoid. 
         [0069]    The second dust bins  310   a  define the plurality of second wet-type dust collecting regions  310   c  to collect minute dust with the rotating water W. The second dust bins  310   a  defining the second wet-type dust collecting regions  310   c  are formed in parallel along the side surface of the first dust bin  300   a  at a location that corresponds to the lower surface of the second centrifugal separating pipes  210   a.    
         [0070]    The first wet-type dust collecting region  300   c  and the plurality of second wet-type dust collecting regions  310   c  are connected in fluid communication with each other at lower portions thereof, so that it is possible to fill the water W concurrently. 
         [0071]    As the centrifugal separating assembly  200  with the structure explained above is connected to the upper portion of the dust bin unit  300 , the wet-type dust collector  1  is constructed. 
         [0072]    If the centrifugal separating assembly  200  is connected to the upper portion of the dust bin unit  300 , the first centrifugal separating pipe  200   a  is inserted into the first dust bin  300   a . At this time, the sealing member  220  is engaged with the water distributing hole  501  to isolate the water distributing passage portion  500  from the first wet-type dust collecting region  300   c.    
         [0073]    If the centrifugal separating assembly  200  is engaged with the dust bin unit  300 , the second introducing pipe units  230  are also inserted into the corresponding second centrifugal separating pipes  210   a,  respectively. 
         [0074]    If the centrifugal separating assembly  200  is engaged with the dust bin unit  300 , the first centrifugal separating pipe  200   a  and the first dust bin  300   a  are engaged with each other, to form a first separating portion A. 
         [0075]    The second centrifugal separating pipes  210   a  and the second dust bins  310   a  form second centrifugal separating portions B′, respectively. The second centrifugal separating portions B′ with the structure explained above, separate minute dust particles which are not removed in the first separating portion A. All the second centrifugal separating portions B′ form a second separating portion B at which minute dust particles, which are not removed at the first separating portion A, are separated. 
         [0076]    In the construction explained above, the centrifugal separating assembly  200  and the dust bin unit  300  may be constructed only with the first centrifugal separating pipes  200   a  and the first dust bins  300   a,  i.e., without requiring the second centrifugal separating pipes and the second dust bins  210   a,    310   a.  In such a case, a combined form of the first centrifugal separating pipes  200   a  and the plurality of second centrifugal separating pipes  210   a,  or the first centrifugal separating pipes  200   a  may become the centrifugal separating pipe according to the present invention. Alternatively, the combined form of the first dust bins  300   a  and the second dust bins  310   a,  or the first dust bins  300   a  alone may become the dust bin unit of the present invention. 
         [0077]    When the wet-type dust collector  1 , connected in the manner explained above, is mounted in the vacuum cleaner (not illustrated), the exhaust chamber  270  is connected to a passage which is in fluid communication with the fan motor unit (not illustrated) of the vacuum cleaner (not illustrated). Further, the first inlet  201  is connected to an introducing passage (not illustrated) connected to a component such as brush assembly (not illustrated). As a result, the wet-type dust collector  1  forms the passage for the air current inside the vacuum cleaner (not illustrated). 
         [0078]    When the vacuum cleaner is driven in the assembled state explained above, externally-drawn air is introduced into the first centrifugal separating regions  200   c  through the first inlet  201 . 
         [0079]    The air introduced into the first centrifugal separating regions  200   c  rotates around the first exhaust pipe unit  210 . As the air rotates around the first exhaust pipe unit  210 , due to the rotational force of the air, water W in the first wet-type dust collecting regions  300   c  of the first dust bins  300   a  also rotates. As a result, foreign matter are separated by the centrifugal force in the first centrifugal separating regions  200   c,  and the separated foreign matters are collected by the rotating water W in the first wet-type dust collecting regions  300   c.    
         [0080]    After the foreign matters are separated due to the centrifugal force from the rotating air and also by the rotating water W at the first separating portion A, the air is introduced into the second passage  240  via the grill  211  and the first exhaust pipe unit  210 . 
         [0081]    The air introduced into the second passage  240  is passed through the plurality of second inlets  231  formed in the partitioning wall  250 , and the second centrifugal separating pipes  210   a  in fluid communication with the second inlets  231 , and then introduced into the second wet-type dust collecting regions  310   c.  As the air is introduced into the second wet-type dust collecting regions  310   c,  the air is rotated in a predetermine direction and discharged by the impeller  235   a.  Accordingly, water W in the second wet-type dust collecting regions  310   c  rotates. Since the water W rotates in the second wet-type dust collecting regions  310   c,  dust is collected due to the surface tension or polarity thereof, while centrifugal force is applied to the minute dust particles entrained in the air discharged into the water W. Accordingly, efficiency of separating and collecting minute dust particles increases. 
         [0082]    After minute dust particles are separated due to the water W in the second wet-type dust collecting regions  310   c,  the air moves upward, passed through the second exhaust passage  602  formed between the second centrifugal separating pipes  210   a  and the second introducing pipe unit  230 , and discharged into the exhaust chamber  270 . 
         [0083]    In the vacuum cleaner operating in the manner explained above, the passage-closing unit  700  prevents leakage of the water W from the dust bin unit  300  to the outside. 
         [0084]      FIG. 4  illustrates water filling up to the level that causes a closing plate  701  of  FIG. 2  to be positioned between the exhaust outlet  212  and the closing plate support rod moving hole  211   d,  and  FIG. 5  illustrates a state in which the closing plate  701  closes the exhaust outlet  212 . 
         [0085]    Referring to  FIGS. 2 ,  4  and  5 , the operation of the passage-closing unit  700  will be explained in greater detail. The passage-closing unit  700  is seated on the upper portion of the locking jaw  211   b , if the water W level is so low that the closing plate  701  is seated on the upper surface of the locking jaw  211   b  (see  FIG. 2 ). 
         [0086]    In such a situation, the normal operation of the wet-type dust collector is performed, in which the suction force is transmitted via the exhaust outlet  212  and the grill  211  to the first wet-type dust collecting regions  300   c,  and the externally-drawn air through the first inlet  201  is separated in the first centrifugal separating pipes  200   a  and the first wet-type dust collecting regions  300   c,  and discharged through the grill  211  and the exhaust outlet  212 . 
         [0087]    Referring to  FIG. 4 , if the water level is at about middle area of the first centrifugal separating regions  200   c,  the floater  703  moves upward due to the buoyant force of the water, and the closing plate connected thereto is placed at about the middle area of the grill. At this situation, the closing plate  701  does not close the exhaust outlet  212 . However, since the closing plate  701  is in proximity to the exhaust outlet  212  according to the water level, the closing plate  701  rises as shown in  FIG. 5  as the suction force is transmitted through the exhaust outlet  212  to thereby close the exhaust outlet  212 . That is, even when the level of water W in the first dust bins  300   a  is lower than the location that enables the closing plate  701  to close the exhaust outlet  212 , if the closing plate is at a location above the middle area of the grill, the suction force transmitted through the exhaust outlet  212  can directly move the closing plate  701  upwardly to close the exhaust outlet  212  as the vacuum cleaner (not illustrated) is driven. 
         [0088]    The water can shake due to the suction force even when the water is filled up to the height as illustrated in  FIG. 4 , and the droplets due to the shaking air may be entrained in the air to leak out through the exhaust outlet. However, the path closing unit constructed according to the present invention prevents leakage of the internal water W of the dust bin unit  300  to outside efficiently. 
         [0089]    Although not explained, the reference numeral  201   b  refers to a backflow preventive rib to prevent backward flow of the water, through the grill  211  when the water shakes in the first wet-type dust collecting regions  300   c.    
         [0090]    The wet-type dust collector  1  with the constitution and function explained above operates as a dry-type dust collector if water W is not filled. 
         [0091]    The above disclosure can be applied in cleaning apparatuses, such as, domestic, commercial, and industrial cleaners. 
         [0092]    Although a few embodiments have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.