Patent Publication Number: US-2007095029-A1

Title: Upright vacuum cleaner

Description:
BACKGROUND  
      This description relates to upright vacuum cleaners used for suctioning dirt and dust from carpets and floors.  
      Upright vacuum cleaners include a cleaner body having a handle, by which an operator of the vacuum cleaner may grasp and maneuver the cleaner, and a nozzle section which travels across a floor, carpet, or other surfaces being cleaned.  
      The cleaner body is often formed as a rigid plastic housing which encloses a dirt and dust collecting filter bag. The underside of the nozzle section includes a suction opening formed therein which is in fluid communication with the filter bag. A suction source such as a motor and fan assembly is enclosed within the cleaner body. The suction source generates the suction force required to pull dirt from the carpet or floor through the suction opening and into the filter bag.  
      Another type of upright vacuum cleaner utilizes cyclonic airflow to avoid the need for vacuum filter bags, and the associated expense and inconveniences of replacing filter bags. The cyclonic airflow is used instead of a filter bag to separate a majority of the dirt and other particulates from the suction airflow. The air is then filtered to remove residual particulates, returned to the motor, and exhausted.  
      However, conventional cyclonic airflow upright vacuum cleaners have not been found to be entirely effective and convenient to use. For example, with conventional cyclonic airflow vacuum cleaners, the process of emptying dust and dirt from dust collector may be inconvenient.  
      Also, in a conventional vacuum cleaner having the above-mentioned configuration, the dirt and dust stored in the dust collector rise because of the swirling forces being produced by the suction source.  
      Also, in the conventional vacuum cleaner having the above-mentioned configuration, the process of handling the cleaner body and the nozzle section is difficult when a user controls the cleaner body for operating the vacuum cleaner.  
     SUMMARY  
      In one general aspect, a vacuum cleaner includes a nozzle section, a cleaner body coupled to the nozzle section and being in fluid communication with the nozzle section, and a dust collecting container operatively coupled with the cleaner body. The vacuum cleaner may include a primary cyclone for separating dust and dirt from a suction airflow flowing into the dust collecting container. The vacuum cleaner may include at least one secondary cyclone disposed along a periphery of the primary cyclone for separating dust and dirt entrained in the airflow discharged from the primary cyclone.  
      The vacuum cleaner may include a discharge member being centrally arranged in the primary cyclone for filtering the airflow prior to the airflow being discharged from the primary cyclone.  
      The vacuum cleaner also may include a floatation prevention member attached to an underside of the discharge member for preventing swirling airflow in the dust collecting container. The floatation prevention member may include an inclined portion and at least one cross blade attached to an underside of the inclined portion.  
      The discharge member may include holes formed along a periphery of the discharge member. The discharge member may be mounted on the upper end of the primary cyclone. An inner diameter of the discharge member may reduce gradually along a central axis of the discharge member.  
      The vacuum cleaner may include a main filter assembly located on an upper part of the at least one secondary cyclone for filtering dust and dirt from the airflow discharged from the at least one secondary cyclone.  
      The suction source may include a suction source inlet adjacent to a secondary airflow outlet of the at least one secondary cyclone.  
      A periphery of the at least one secondary cyclone may be partially defined by the dust collecting container.  
      A primary airflow inlet of the primary cyclone may be tangentially oriented in relation to an axial centerline of the primary cyclone and a primary airflow outlet of the primary cyclone is located in a center of an upper surface of the primary cyclone.  
      A secondary airflow inlet of the at least one secondary cyclone may be located in an upper periphery of the at least one secondary cyclone and the secondary airflow outlet of the at least one secondary cyclone may be located along a longitudinal axis of the at least one secondary cyclone.  
      The dust collecting container may include a primary dust storing part for storing dust and dirt separated in the primary cyclone. The dust collecting container may include a secondary dust storing part for storing dust and dirt separated in the at least one secondary cyclone.  
      In another general aspect, a vacuum cleaner includes a nozzle section, a cleaner body coupled to the nozzle section and in fluid communication with the nozzle section, and a dust collecting container operatively coupled with the cleaner body. The vacuum cleaner may include a primary cyclone for separating dust and dirt from a suction airflow flowing into the dust collecting container.  
      The vacuum cleaner may include at least one secondary cyclone for separating dust and dirt entrained in the airflow discharged from the primary cyclone.  
      The vacuum cleaner may include a main filter assembly located on an upper part of the at least one secondary cyclone for filtering dust and dirt from the airflow discharged from the at least one secondary cyclone. The main filter assembly may include a main filter element and a filter supporter for supporting and installing the main filter element. An auxiliary filter assembly may be disposed downstream from the main filter assembly.  
      The vacuum cleaner may include a bottom panel coupled to the dust collecting container for covering the dust collecting container. The primary cyclone may be located in the dust collecting container and a periphery of the at least one secondary cyclone may be at least partially defined by the dust collecting container.  
      In another general aspect, an upright vacuum cleaner includes a nozzle section, an upright cleaner body pivotally mounted to the nozzle section and in fluid communication with the nozzle section, and a rotation shaft provided at the upright cleaner body for pivotally mounting the upright cleaner body to the nozzle section. The vacuum cleaner may include a body release lever for selectively controlling an inclined operative position of the upright vacuum cleaner. The vacuum cleaner may include an agitator motor mounted in the nozzle section for driving an agitator of the vacuum cleaner. The vacuum cleaner may include a suction source mounted in the upright cleaner body for generating a suction force in the upright cleaner body.  
      The vacuum cleaner may include a dust collecting container selectively mounted in at least one of the upright cleaner body and the nozzle section.  
      The vacuum cleaner may include a primary cyclone for separating dust and dirt from a suction airflow flowing into the dust collecting container. The vacuum cleaner also may include at least one secondary cyclone for separating dust and dirt entrained in the airflow discharged from the primqary cyclone. The at least one secondary cyclone may be disposed along a periphery of the primary cyclone. The at least one secondary cyclone and the primary cyclone may be formed as a single piece.  
      The main filter assembly may be located on an upper part of the at least one secondary cyclone for filtering dust and dirt from the airflow discharged from the at least one secondary cyclone.  
      The primary airflow inlet of the primary cyclone may be tangentially oriented in relation to an axial centerline of the primary cyclone.  
      The dust collecting container may include a primary dust storing part for storing dust and dirt separated in the primary cyclone. The dust collecting container may include a secondary dust storing part for storing dust and dirt separated in the at least one secondary cyclone.  
      The vacuum cleaner may include a top cover detachably connected to the dust collecting container and positioned at an upper end of the dust collecting container.  
      The vacuum cleaner may include a conduit extending from the at least one secondary cyclone to the suction source.  
      The vacuum cleaner may include a primary airflow outlet of the primary cyclone located in a center of an upper surface of the primary cyclone.  
      The at least one secondary cyclone may include a plurality of secondary cyclones disposed along a periphery of the primary cyclone. The vacuum cleaner may include secondary airflow inlets for each of the secondary cyclones, the secondary airflow inlets being positioned above a position of the primary airflow outlet of the primary cyclone.  
      The vacuum cleaner may provide a simple coupling structure, may be convenient to use, and may prevent dust and dirt from rising out of dust collection container due to the spiral airflow.  
      Other features and advantages will be apparent from the following description, including the drawings, and the claims.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a perspective view of a cyclonic airflow upright vacuum cleaner.  
       FIG. 2  is a partial, perspective view of an operative mode of the upright vacuum cleaner of  FIG. 1 .  
       FIG. 3  is a side view of the vacuum cleaner of  FIG. 1 .  
       FIG. 4  is a rear view of the vacuum cleaner of  FIG. 1 .  
       FIG. 5  is a bottom, plan view of the vacuum cleaner of  FIG. 1 .  
       FIG. 6  is a partial, side sectional view of the vacuum cleaner of  FIG. 1 .  
       FIG. 7  is an exploded, perspective view of the dust collector shown in  FIG. 1 .  
       FIG. 8  is a perspective view illustrating an upper part of the dust collector shown in  FIG. 7 .  
       FIG. 9  is a partial, side sectional view of the dust collector shown in  FIG. 7 . 
    
    
     DETAILED DESCRIPTION  
      Referring to  FIGS. 1-6 , an upright vacuum cleaner includes a cleaner body  100 , a nozzle section  200  connected to the cleaner body  100 , and conduits for guiding the suction airflow from the nozzle section  200  to the atmosphere while passing through the cleaner body  100 .  
      The cleaner body  100  and the nozzle section  200  are connected through a pivot or hinge, such as a suitable hinge assembly, so that the cleaner body  100  pivots between a generally vertical storage position (as shown) and an inclined, operative position. The hinge assembly includes a rotation shaft  150  and rotating shaft holes  151  corresponding to the rotation shaft  150 . The rotation shaft  150  protrudes from two lower opposing sides of the cleaner body  100  and the rotating shaft holes are provided at nozzle section  200  for retaining the rotation shaft  150 .  
      The cleaner body  100  and nozzle section  200  are connected to each other as the rotation shaft  150  is inserted into the rotating shaft hole  151 , allowing the cleaner body and the nozzle section to rotate freely with respect to each other.  
      The nozzle section  200  includes a nozzle case  210 , a suction opening  211  which is formed at the underside of the nozzle case  210 , and a rotating brush assembly which is provided in the nozzle case  210 . Front wheels  121  and rear wheels  120  are rotatably mounted to underside of the nozzle case  210  to enable the nozzle section  200  to smoothly move on a floor.  
      The suction opening  211  extends substantially across the width of the nozzle case  210  at the front end thereof. The suction opening  211  is in fluid communication with the cleaner body  100  through a first conduit  410 .  
      The rotating brush assembly includes an agitator  220 , an agitator brush  230  which is provided at the outer circumference of the agitator  220 , and an agitator motor  280  for driving the agitator  220 .  
      The agitator  220  is positioned in the region of the suction opening  211  for contacting and scrubbing the surface being vacuumed to loosen embedded dirt and dust. The agitator  220  is axially connected to a shaft of the agitator motor  280  mounted in the nozzle case  210 . When the rotational force of the agitator motor  280  is transferred to the agitator  220 , the agitator rotates and brushes up contaminants from the surface being cleaned.  
      In addition to the agitator motor  280 , a suction source  180  is mounted in the cleaner body for generating a suction force in the cleaner body  100 . In this case, it is preferable that a is capacity of the agitator motor is smaller than that of the suction source.  
      A height adjustment knob  110  is rotatably mounted in the nozzle section  200 . The user rotates the height adjustment knob  110  with his/her hand to raise or lower a shaft supporting front wheels (not shown) of the vacuum cleaner, and thus adjust the height of the nozzle section  200 . In one implementation, the height adjustment knob  110  is capable of adjusting the height of the nozzle section incrementally and in accordance with the state of the surface to be cleaned.  
      The cleaner body  100  includes a control part (not shown) for controlling the vacuum cleaner, the suction source  180  for generating the required suction airflow for cleaning operations, and a dust collector  300  for separating contaminants entrained in the suction airflow passed through the suction opening  211 . The cleaner body may also include a coupling device including a latch  327  and a coupling protrusion  190  for coupling the dust collector to the cleaner body. The cleaner body may further include a socket  195  for selectively holding the dust collector  300 . The socket is formed as a recess having several grooves corresponding to the surface of the dust collector.  
      The suction source  180  includes an electronic motor and a fan generating a suction force in a suction source inlet  181  and an exhaust force in a suction source outlet  183 .  
      The suction source outlet  183  is in fluid communication with a final filter assembly  600  for filtering the exhaust airflow of any contaminants immediately prior to its discharge into the atmosphere. The suction source inlet  181  is in fluid communication with the dust collector  300  of the cleaner body  100 . Alternatively, the suction source may be disposed in the nozzle section  200 .  
      The cleaner body  100  further includes a handle  700  extending upwardly therefrom by which a user of the vacuum cleaner is able to grasp and maneuver the vacuum cleaner. The handle  700  includes a telescopic release lever  710  for adjusting the height of the handle according to a height of the user.  
      The cleaner body  100  further includes a cord hook provided at rear side of the cleaner body  100 . The cord hook includes an upper cord hook  141  and a lower cord hook  140  corresponding to the upper cord hook. The space between the upper cord hook  141  and the lower cord hook  140  is sufficient to accommodate the number of turns necessary to store the entire length of the cord. A cord holder (not shown) adjacent to the cord hook prevents the cord releasing from its stored position.  
      The conduits include a first conduit  410  connecting the suction opening  211  to dust collector  300 , a second conduit  420  connecting the dust collector  300  to the suction source inlet  181 , and a third conduit  430  connecting the suction source outlet  183  to the atmosphere.  
      The first conduit  410  includes hoses supported and connected by fitting members. One side of a first fitting member  171  is connected to a first hose  411  and the other side of the first fitting member  171  is connected to a passage  170  which is in fluid communication with the suction opening  211 .  
      A second fitting member  173  connects the first hose  411  to a second hose  412  and a third fitting member  175  connects the second hose  412  to the cleaner body. Each of first and second hose ( 411 ,  412 ) is detachably connected to the second fitting member  173 . The vacuum cleaner further includes a body release lever  130  for an inclined, operative position of the vacuum cleaner. The body release lever  130  is pivotably mounted on a mounting portion  131  which is provided at the nozzle section. The body release lever  130  has a locking protrusion  132  protruding from a side thereof. The locking protrusion  132  is sequentially locked in one or more locking recesses  135  provided at a lower side of cleaner body. When the vacuum cleaner is in use, a locking protrusion  132  is locked in one of the inclined position recesses  135  with the cleaner body  100  rotated at a predetermined angle with respect to a surface to be cleaned.  
      Referring to the  FIGS. 7-9 , the dust collector  300  includes a cyclonic chamber  320 , a dust collecting container  330 , a bottom panel  340  which is positioned at a lower end of the dust collecting container  330  and a top cover  310  which is positioned at an upper end of the cyclonic chamber  320 .  
      The dust collecting container and the cyclonic chamber may be formed as a single piece.  
      The dust collector  300  further includes a dust collector handle  350  which is provided on the exterior of the dust collecting container  330  for handling the container. The latch  327  is positioned at the upper end of the dust collector handle  350  for coupling the dust collector to the cleaner body, and the coupling protrusion  190  (as shown in  FIG. 6 ) is formed at a front portion of the cleaner body.  
      The cyclonic chamber  320  includes a primary cyclone  321  and at least one secondary cyclone  323 . The primary cyclone  321  separates dust and dirt from the suction airflow passed through the suction opening  211 . The secondary cyclone  323  separates dust and dirt entrained in the airflow discharged from the primary cyclone  321 .  
      The primary cyclone  321  has a downwardly-opened, cylindrical container shape. A primary airflow inlet  321   a  is formed through an upper portion of the primary cyclone  321  at one side of the primary cyclone  321 . A primary airflow outlet  321   b  is formed through the top of the primary cyclone  321  so that the primary airflow outlet  321   b  extends vertically.  
      The primary airflow inlet  321   a  is tangentially oriented and arranged so that the airflow entering the primary cyclone  321  through the primary airflow inlet  321   a  moves in a spiral within the primary cyclone  321 . That is, the primary airflow inlet  321   a  guides dirt-laden air into the cyclonic chamber  320  in a tangential direction of the primary cyclone  321  so that the air flows spirally along an inner wall surface of the primary cyclone  321 .  
      The one or more secondary cyclones  323  have peripheral walls formed integrally with a peripheral wall of the cyclonic chamber  320 . The secondary cyclones  323  are partitioned each from other by peripheral walls of the secondary cyclones  323 . The cyclonic chamber  320  may be constructed as a single piece with the dust collecting container  330  and at least partially defining the dust collecting container  330 .  
      In particular, the secondary cyclones  323  are circumferentially arranged around the primary cyclone  321 . Each secondary cyclone  323  has an upper end upwardly protruding to a level higher than that of the upper end of the primary cyclone  321 .  
      The peripheral wall of each secondary cyclone  323  is vertically cut out at a region where the peripheral wall is upwardly protruded above the upper end of the primary cyclone  321 , thereby forming a secondary airflow inlet  323   a  communicating with the primary airflow outlet  321   b.    
      Each secondary cyclone  323  may also be formed with a partial conical shape. The secondary cyclone  323  has a conical portion  323   d  formed at a lower portion of the secondary cyclone  323  such that the conical portion  323   d  has a diameter gradually reduced as the conical portion extends toward the bottom of the dust collecting container  330 .  
      A contaminants discharge port  323   c  is formed at a lower end of each secondary cyclone  323  to downwardly discharge contaminants such as dust.  
      The secondary cyclones  323  have an integrated structure such that adjacent secondary cyclones of the secondary cyclones  323  are in contact with each other to prevent air from leaking between the adjacent secondary cyclones  323 .  
      The cyclonic chamber  320  may further include a chamber cover  325  mounted to the upper end of the cyclonic chamber  320  to open or close the upper ends of the secondary cyclones  323 .  
      A flow passage guide  326  is provided at the underside of the chamber cover  325 . The flow passage guide  326  guides air emerging from the primary airflow outlet  321   b  more smoothly to the secondary cyclones  323 .  
      The secondary airflow inlet  323   a  of each secondary cyclone  323  guides air discharged from the primary airflow outlet  321   b  to flow in a tangential direction of the secondary cyclone  323 , so that the air entering the secondary airflow inlet  323   a  flows spirally along an inner wall surface of the secondary cyclone  323 . Secondary airflow outlets  323   b  are formed at the chamber cover  325  along the peripheral portion of the chamber cover  325  to discharge air from the secondary cyclones  323 .  
      Dust separated in the primary cyclone  321  and secondary cyclones  323  is stored in a dust storing part formed by the dust collecting container  330  and the bottom panel  340 . The stored dust is subsequently outwardly discharged by virtue of gravity when the bottom panel  340  is opened.  
      An opening/closing device  360  is mounted to the peripheral wall of the dust collecting container  330  to open or close the bottom panel  340 . The opening/closing device  360  includes a locking hook  361  for locking the bottom panel  340 . The bottom panel  340  may include a bottom hook  341  corresponding to the locking hook  361 .  
      The dust collecting container  330  may be at least partially transparent so that an operator of the vacuum cleaner is able to view the level of dirt and dust accumulated therein for purposes of determining when the dust collecting container should be emptied.  
      The dust storing part may include a primary dust storing part  331  for storing the dust separated by the primary cyclone  321 , and a secondary dust storing part  333  for storing dust separated by the secondary cyclones  323 .  
      The primary dust storing part  331  and secondary dust storing part  333  are partitioned by a substantially cylindrical boundary wall  335 , which is connected to the secondary cyclones  323 , and has a diameter smaller than that of the peripheral wall of the dust collecting container  330 .  
      The boundary wall  335  has a lower end extending downward to the bottom of the dust collecting container  330 , such as the upper surface of the bottom panel  340 , beyond the lower end of the primary cyclone  321 .  
      The boundary wall  335  may have a circumferentially corrugated shape, in order to prevent the dust stored in the primary dust storing part  331  from floating upwardly due to a spiral air flow formed in the primary cyclone  321 .  
      A sealing member  342  is mounted between the boundary wall  335  and the bottom panel  340 . The sealing member  342  having a cylindrical shape may be made from an elastic material. Accordingly, the sealing member  342  prevents the primary dust storing part  331  from communicating with the secondary dust storing parts  333 .  
      Other implementations may include a dust collector  300  including a discharge member  370  mounted on the upper end of the primary cyclone  321 . A plurality of holes  371  are formed at a peripheral wall of the discharge member  370  in order to allow the discharge member  370  to communicate with the primary airflow outlet  321   b  of the primary cyclone  321 .  
      The discharge member  370  may be centrally arranged in the primary cyclone  321 , may extend axially through the primary cyclone  321 , and may have a substantially conical structure having an opened upper end and a closed lower end while having a diameter gradually reducing as the discharge member  370  extends downward.  
      When the discharge member  370  has such a structure, the velocity of the spiral air flow in the primary cyclone  321  is gradually reduced toward the lower end of the primary cyclone  321 . Therefore, it is possible to prevent dust from being influenced by a suction force exerted in the discharge member  370 . Alternatively, the discharge member  370  may have a cylindrical shape.  
      The upper end of the discharge member  370  is separably coupled to the peripheral edge of the primary airflow outlet  321   b . For example, a coupling part  376  is coupled to a coupling protrusion  321   c  formed at the upper edge of the primary airflow outlet  321   b . An annular sealing member (not shown), which provides a sealing effect, is interposed between the upper end of the discharge member  370  and the primary airflow outlet  321   b.    
      A floatation prevention member  373  may also be mounted to the lower end of the discharge member  370  in order to prevent the dust collected in the primary dust storing part  331  from rising due to the spiral air flow and entering the secondary cyclones  323 .  
      For example, the floatation prevention member  373  may have an inclined portion formed integrally with the lower end of the discharge member  370 . The inclined portion may also have a radially-extending and downwardly-inclined, upper surface. Specifically, the floatation prevention member  373  may have a conical structure having a diameter gradually increasing as the floatation prevention member  373  extends downward.  
      A cross blade  375  may be attached under the inclined portion for preventing swirling airflow and air turbulence in the primary dust storing part  331  causing dust to rise up. However, the structure of the floatation prevention member  373  may be modified for specific airflows.  
      The dust collector  300  may include a guide rib  380  provided at the primary cyclone  321 . The guide rib  380  guides air entering the primary airflow inlet  321   a  to flow in a direction tangential to the inner peripheral wall surface of the primary cyclone  321 . The guide rib  380  prevents the air entering the primary airflow inlet  321   a  from being directly introduced into the discharge member  370 .  
      A main filter assembly  500  may be located on the dust collector  300  for filtering contaminants from the airflow discharged from the secondary cyclone  323 .  
      The main filter assembly  500  includes a filter housing  510  and a main filter element  520  mounted in the filter housing  510 , and a filter housing knob  530  for handling the filter housing. The filter housing  510  is detachably coupled to the cleaner body and receives and retains the main filter element  520 . The filter housing  510  includes a plurality of apertures, slots, or other passages formed therethrough, such as in the lower half thereof, so that the suction airflow flows freely from the cover discharge port  313 , into the filter housing  510  and to the main filter element  520 .  
      The main filter element  520  may be made of permeable material. For cleaning the main filter element  520 , the user is able to detach the filter housing  510  from the cleaner body by rotating and drawing out the filter housing knob  530 .  
      The main filter element  520  may include Porex R™ brand high density polyethylene-based, open-celled porous media available commercially from Porex Technologies Corp., Fairburn, Ga. 30213, or an equivalent foraminous filter member. The main filter element  520  is a rigid open-celled foam that is moldable, machinable, and otherwise workable into any shape as deemed advantageous for a particular application. The preferred filter element has an average pore size in the range of 45 μm to 90 μm to optimize filtration, but also to allow sufficient airflow rates.  
      The main filter assembly  500  may further include a filter supporter (not shown) for supporting and fixing the main filter element  520 . The filter supporter may be formed at the inner frame of the filter housing. The main filter assembly  500  may be positioned in the top cover  310 .  
      The cleaner body  100  also includes a final filter assembly  600  for filtering the suction airflow immediately prior to its exhaustion into the atmosphere. The preferred final filter assembly  600  includes a final filter element  610  and a final filter housing  620  for retaining the final filter element.  
      The final filter element  610  may be a high efficiency particulate arrest (HEPA) filter element in a sheet or block form. The final filter housing  620  has protective grid or grate structure for securing the final filter element  610  in place.  
      The vacuum cleaner may further include an auxiliary filter assembly (not shown) disposed downstream from the main filter assembly. The auxiliary filter assembly includes an auxiliary filter element (not shown), a filter supporter for supporting and installing the auxiliary filter element, and an auxiliary filter housing (not shown) for retaining the auxiliary filter element. The final filter assembly  600  will remove the contaminants, such that only contaminant-free air is discharged into the atmosphere. An exemplary operation of the vacuum cleaner will be described with reference to  FIGS. 1-9 .  
      The activation of the suction source  180  establishes a suction force at its suction source inlet  181 , in the elongated first conduit, and thus in the primary cyclone  321 .  
      The suction force or negative pressure in primary cyclone  321  is communicated to the suction opening  211  formed in the nozzle underside through the hoses and associated fitting members. In combination with the scrubbing action of the rotating brush assembly, the suction force causes dust and dirt from the surface being cleaned to be entrained in the suction airflow and pulled into the primary cyclone  321  through the primary airflow inlet  321   a.    
      The air introduced into the primary cyclone  321  is guided by the guide rib  380  to flow in a direction tangential to the inner peripheral surface of the primary cyclone  321  without being directly introduced into the discharge member  370 , thereby forming a spiral flow.  
      The air acquires a certain swirling force, and the swirling force separates heavy and large dust particles. As a result, relatively heavy and large dust is separated from the air in accordance with the cyclone principle, and is then stored in the primary dust storing part  331  after falling downward.  
      The dust stored in the primary dust storing part  331  is prevented from floating in accordance with the functions of the floatation prevention member  373  and corrugated boundary wall  335 . The air, from which relatively heavy and large dust has been separated, is discharged from the primary cyclone  321  through the primary airflow outlet  321   b  communicating with the holes  371  formed at the peripheral wall of the discharge member  370 .  
      The finer dust is then filtered through the discharge member  370  placed between the primary cyclone  321  and the secondary cyclones  323 . The air is then introduced into the secondary cyclones  323  so that the air is again subjected to a dust separation process in order to separate relatively light and fine dust from the air.  
      The air, from which relatively light and fine dust has been separated in the secondary cyclones  323 , is introduced into the interior of the top cover  310  detachably connected to the dust collecting container  330 .  
      The air introduced into the interior of the top cover  310  is discharged through a cover discharge port  313  formed at the center of the top cover  310 . The air emerging from the cover discharge port  313  is introduced into the main filter assembly  500 .  
      The air passes through the apertures formed in the filter housing  510 , passes through the main filter element  520  so that residual contaminants are removed, and exits the main filter assembly  500 . The air discharging from the main filter assembly  500  is introduced into the suction source  180  through the second conduit  420 . The air emerging from the suction source outlet  183  is then introduced into the final filter assembly  600  through the third conduit  430 .  
      In the final filter assembly  600 , the air is filtered again by the HEPA filter to remove any contaminants that passed through the dust collector  300  and the main filter assembly  500 . The air passed through the final filter assembly  600  is discharged outwardly from the vacuum cleaner to atmosphere.  
      Implementations of the above-described vacuum cleaner may provide one or more of the following advantages. For example, the simple coupling structure may be relatively convenient to use since the cleaner body is coupled to the nozzle section by a simple hinge assembly.  
      Dust and dirt are prevented from rising due to the spiral airflow by the floatation prevention member restricting the spiral movement of the dirt and dust. The vacuum cleaner may also separate dust and dirt from the airflow and deposit the dust and dirt easily and conveniently into the dust collecting container.  
      Other implementations are within the scope of the following claims.