Abstract:
A vacuum cleaner with a separation module includes an advanceable filter media for filtering a debris-containing working airstream. The filter media can extend over an exhaust grill having openings through which air may pass. The filter media can be mounted on a pair of moveable reels, such that the filter media can periodically be replaced with new filter media.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application No. 61/715,404, filed Oct. 18, 2012, which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    Upright vacuum cleaners employing separation modules are well known. Some separation modules use frusto-conical-shaped separators and others use high-speed rotational motion of the air/debris to separate the debris (which may include dirt, dust, soil, hair, and other debris) by centrifugal force. Typically, working air enters and exits at an upper portion of the separation module and the bottom portion of the separation module is used to collect debris. Before exiting the separation module or passing to a downstream separation stage, the working air may flow through an exhaust grill. The exhaust grill can have openings through which air may pass. The openings may be defined by perforations or holes, or may be defined between spaced vanes or louvers. In some cases, a foam filter is provided inside or on the exterior of the exhaust grill. During operation, the foam filter may become clogged with debris, which inhibits or prevents air flow through the vacuum cleaner. A user must then stop vacuuming to clean or replace the foam filter. 
       BRIEF SUMMARY 
       [0003]    According to one aspect of the invention, a vacuum cleaner includes a housing comprising a suction nozzle, a suction source provided on the housing in fluid communication with the suction nozzle for creating a working airstream through the housing, and a filter assembly positioned within the working airstream, the filter assembly having a supply reel, a take-up reel, and a filter media wound about the supply reel and connected to the take-up reel, and positioned within the path of the working airstream to filter air passing through the filter assembly, wherein the filter media can be advanced from the supply reel to the take-up reel by rotation of the supply and take-up reels. 
         [0004]    According to another aspect of the invention, a vacuum cleaner includes a housing comprising a suction nozzle, a suction source provided on the housing in fluid communication with the suction nozzle, a cyclone separator having at least one separation chamber for separating contaminants from a debris-containing working airstream and comprising an air inlet in fluid communication with the suction nozzle and an air outlet, a collection chamber adjacent to the cyclone separator for receiving contaminants separated by the cyclone separator, an exhaust grill defining at least one opening in fluid communication with the air outlet, and a roll of filter media having a portion overlying the at least one opening of the exhaust grill to filter air passing through the exhaust grill, wherein the filter media is advanced relative to the exhaust grill to replace the portion overlying the at least one opening of the exhaust grill with an unused portion of the filter media. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    In the drawings: 
           [0006]      FIG. 1  is a perspective view of a vacuum cleaner having a separation module according to a first embodiment of the invention; 
           [0007]      FIG. 2  is a cross-sectional view through line II-II of the separation module of  FIG. 1 ; 
           [0008]      FIG. 3  is an exploded view of the separation module of  FIG. 1 , the separation module including a filter assembly; 
           [0009]      FIG. 4  is a top cross-sectional view through the filter assembly of  FIG. 3 ; 
           [0010]      FIG. 5  is a side cross-sectional view through the filter assembly of  FIG. 3 ; and 
           [0011]      FIG. 6  is a cross-sectional view through a separation module according to a second embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    The invention relates to vacuum cleaners and in particular to vacuum cleaners having cyclonic dirt separation. In one of its aspects, the invention relates to an improved exhaust grill for a cyclone module assembly. For purposes of description related to the figures, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in  FIG. 1  from the perspective of a user behind the vacuum cleaner, which defines the rear of the vacuum cleaner. However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. 
         [0013]    Referring to the drawings, and in particular to  FIG. 1 , an upright vacuum cleaner  10  comprises housing illustrated as an upright handle assembly  12  and a foot assembly  14  pivotally mounted to the upright handle assembly  12 . The handle assembly  12  further comprises a primary support section  16  with a grip  18  on one end to facilitate movement by a user. A motor cavity  20  is formed at an opposite end of the handle assembly  12  to contain a conventional suction source such as a vacuum fan/motor assembly (not shown) oriented transversely therein for creating a working airstream through the housing of the vacuum cleaner  10 . A post-motor filter housing  22  is formed above the motor cavity  20  and is in fluid communication with the vacuum fan/motor assembly. The handle assembly  12  pivots relative to the foot assembly  14  through a pivot axis that is coaxial with a motor shaft (not shown) associated with the vacuum fan/motor assembly. A mounting section  24  on the primary support section  16  of the handle assembly  12  receives a separation module  26  according to a first embodiment of the invention for separating debris (which may include dirt, dust, soil, hair, and other debris) and other contaminants from the debris-containing working airstream created by the suction source and collecting the debris for later disposal. As illustrated herein, the separation module  26  is shown as a cyclone module assembly  26 . However, it is understood that other types of separation modules can be used, such as centrifugal separators or bulk separators. 
         [0014]    The foot assembly  14  comprises a housing  28  with a suction nozzle  30  formed at a lower surface thereof and that is in fluid communication with the vacuum fan/motor assembly. While not shown, an agitator can be positioned within the housing  28  adjacent the suction nozzle  30  and operably connected to a dedicated agitator motor, or to the vacuum fan/motor assembly within the motor cavity  20  via a stretch belt as is common in the vacuum cleaner art. Rear wheels  32  are secured to a rearward portion of the foot assembly  14  and a pair of support wheels (not shown) are secured to a forward portion of the foot assembly  14  for moving the foot assembly  14  over a surface to be cleaned. 
         [0015]      FIG. 2  is a sectional view through the separation module  26  of  FIG. 1 . The separation module  26  illustrated herein comprises a single-stage cyclone separator  34  for separating contaminants from the debris-containing working airstream and a dirt cup  36  which receives contaminants separated by the cyclone separator  34 . The cyclone separator  34  defines a separation chamber  38  and comprises a side wall  40 , a top wall  42 , and an open bottom defined by an edge  44 . An inlet  46  to the separation chamber  38  is formed in the side wall  40  and can be defined by an inlet conduit extending outwardly from the side wall  40 . While not illustrated, the inlet  46  is in fluid communication with the suction nozzle  30  ( FIG. 1 ). 
         [0016]    The dirt cup  36  defines a collection chamber  48 , and comprises a side wall  50 , a bottom wall  52 , and an open top defined by an edge  54  that is selectively joined to the bottom edge  44  of the cyclone separator  34 . A gasket  56  can be provided between the edges  44 ,  54 . While the separation chamber  38  and collection chamber  48  are shown herein as being defined by separate housings, it is also contemplated that the separation chamber  38  and collection chamber  48  can be defined by a common or integral housing. In this case, the bottom wall  52  defining the collection chamber  48  can be provided with a dirt door for selectively releasing debris collected therein. In this case, the separation module can be referred to as a “bottom-empty” separation module. 
         [0017]    An air outlet  58  from the separation module  26  can be provided in the top wall  42  of the cyclone separator  34 . While not illustrated, the outlet  58  is in fluid communication with the suction source in the motor cavity  20  ( FIG. 1 ). The separation module  26  further comprises a filter assembly  60  positioned within the separation chamber  38 , downstream of the outlet  58 . The filter assembly  60  can be at least partially detachably mounted within the separation module  26  and includes a filter housing  62 , a bottom cover  64 , and a replaceable, dual-cartridge filter  66 . 
         [0018]      FIG. 3  is an exploded view of the separation module  26 . The filter housing  62  comprises a cylindrical body having a side wall  68 , an open bottom defined by a bottom edge  70 , and a top wall  72 . The top wall  72  includes an opening defining an air outlet  74  from the filter assembly  60 . The top wall  72  can further include means for attaching the filter housing to the separation module  26 , such as a screw-type or bayonet fastener  76 . The bottom cover  64  is removably attached to the bottom edge  70  of the filter housing  62 , and closes the open bottom of the filter housing  62 . 
         [0019]    The side wall  68  is provided with an exhaust grill  78  and a closed portion  80 . The exhaust grill  78  includes a plurality of vertical vanes or louvers  82  and openings  84 , which are defined between adjacent louvers  82 . The openings  84  provide an air inlet to the filter assembly  60 . Two slots  86  are provided in the side wall  68 , on either side of the exhaust grill  78 . The closed portion  80  of the side wall  68  may be positioned adjacent the inlet  46  of the separation module  26 , and prevents working air entering the cyclone separator  34  from immediately passing through the filter assembly  60 . Instead, the working air must travel at least partially around the cyclone separator  34 , which increases separation efficiency. 
         [0020]    The dual-cartridge filter  66  comprises a roll of sheet-type filter media  88  and two cartridges, including a supply cartridge  90  which holds unused filter media  88  and a take-up cartridge  92  which collects and holds soiled filter media  88 . The cartridges  90 ,  92  can be fixedly mounted within the filter housing  62 , and removable therefrom as unit since they are connected to each other by the filter media  88 . As best shown in  FIG. 4 , the supply cartridge  90  includes a slot  94  providing an exit for unused filter media  88  and the take-up cartridge  92  includes a similar slot  96  providing an entrance for the soiled filter media  88 . 
         [0021]    The filter media  88  stretches between the supply cartridge  90  and the take-up cartridge  92 , such that there is an exposed portion  98  of the filter media  88  which is positioned to filter air passing through the filter housing  62 . The exposed portion  98  can overlie the openings  84  of the exhaust grill to filter air passing through the exhaust grill  78 . Specifically, in the embodiment shown herein, the filter media  88  extends between the slots  94 ,  96  and is threaded through the slots  86  in the filter housing  62 , such that the exposed portion  98  of the filter media  88  is located on the exterior of the filter housing  62 , over the exhaust grill  78 . Alternatively, the exposed portion  98  of the filter media  88  can be located on the interior of the filter housing  62 , but still overlie the exhaust grill  78 . 
         [0022]    Although not shown in the figures, alignment features can be formed on the filter housing  62  for aligning the filter media  88  on the exterior of the filter housing  62 , relative to the openings  84 . Examples of alignment features can include flanges or channels that engage the edges of the filter media  88  to limit its vertical position so that the filter media  88  always covers the openings  84  and filters air passing therethrough. Alternatively, the height of the openings  84  can be reduced, which increases the overlap between the upper and lower edges of filter media  88  and solid portion of the filter housing  62  so that the filter media  88  always covers the openings  84  and filters air passing therethrough. 
         [0023]    The filter media  88  can comprise a long, thin sheet of an air filtration material. One example is a porous, melt-blown sheet material, such as polypropylene, polyethylene terephthalate, or fine glass fiber sheets. The filter media  88  can further comprise a fragrance additive and/or an odor eliminator, one example of which is Febreze®. 
         [0024]      FIG. 5  is a cross-sectional view through the filter assembly  60 . The supply cartridge  90  comprises an internal chamber  100  which contains a supply reel  102  on which the unused filter media  88  is wound. The supply reel  102  is supported within the supply cartridge  90  for rotation, such as via a bearing assembly  104 . When initially installed, the supply reel  102  can hold a roll of the filter media  88 , with one end of the filter media  88  coupled to the supply reel  102 . 
         [0025]    The take-up cartridge  92  comprises an internal chamber  106  which contains a take-up reel  108  on which the soiled filter media  88  is wound. The take-up reel  108  is supported within the take-up cartridge  92  for rotation, such as via a bearing assembly  110 . When initially installed, the take-up reel  108  can hold very little filter media  88 , with one end of the filter media  88  coupled to the take-up reel  108 . The take-up reel  108  is adapted to collect soiled filter media  88  by rotating to wrap the filter media  88  around the reel  108 , which also acts to pull unused filter media  88  off the supply reel  102 . 
         [0026]    The bottom cover  64  includes an actuator  112  for a filter advancing mechanism  114 , which controls the movement of the filter media  88  onto the take-up reel  108  and off of the supply reel  102 . The example of the filter advancing mechanism  114  shown herein comprises a gear train  116  coupling the actuator  112  to the take-up roll  108 . The actuator  112  shown herein is a rotatable knob  118  provided on the exterior surface of the cover  64  which is coupled to a drive gear  120  provided on the interior surface of the cover  64 . The drive gear  120  is enmeshed with a driven gear  122  which is fixedly coupled to the take-up reel  108 . Rotation of the knob  118  is transmitted to the take-up reel  108  via the enmeshed gears  120 ,  122 , such that when a user rotates the knob  118 , the take-up reel  108  rotates to pull the filter media  88  across the exhaust grill  78  and around the take-up reel  108 . The force on the filter media  88  also rotates the supply reel  102  as unused filter media  88  is pulled off the supply reel  102 . 
         [0027]    The dual-cartridge filter  66  is positioned so that the exposed portion  98  of the filter media  88  wraps around the exterior side of the exhaust grill  78 . As the exposed portion  98  of the filter media  88  becomes clogged with debris during use, the user can manually index the take-up reel  108 , by rotating the knob  118 , to pull a clean, fresh portion of filter media  88  from the supply reel  102  around the exhaust grill  78 . The soiled portion of the filter media is collected by the take-up reel  108 . Thus, the user does not have to remove the filter assembly  60  from the vacuum cleaner  10  in order to replace the exposed portion  98  of the filter  88 . In the illustrated embodiment, the user can remove the dirt cup  36  to access the knob  118 . When provided on a bottom-empty separation module, the user can remove the separation module from the vacuum cleaner and open the dirt door to access the knob  118 . 
         [0028]    The filter advancing mechanism  114  can be an indexable mechanism, such that one particular operation is repeated at defined intervals of actuator  112  movement. In one example, one full rotation of the knob  118  can be sufficient to replace the soiled filter media over the exhaust grill  78  with unused filter media. In another example, half of a full rotation of the knob  118  can be sufficient to replace the soiled filter media over the exhaust grill  78  with unused filter media. The filter advancing mechanism  114  can be provided with a user feedback feature which can let a user know when the knob  118  has been rotated a sufficient amount to replace the soiled filter media over the exhaust grill  78  with unused filter media, such as by providing tactile feedback or audible feedback, such as a click sound. 
         [0029]    Referring to  FIG. 2 , a sensor  124  can be provided for detecting a condition indicative of the need to replace the filter media  88 . The sensor  124  can alert the user to the condition, such as by turning on an indicator light  126  on the vacuum cleaner  10 . When the indicator light  126  is on, the user is prompted to manually index the take-up reel  108  to pull a clean, fresh portion of filter media  88  from the supply reel  102  around the exhaust grill  78 . One example of a suitable sensor  124  is an airflow sensor that detects a decrease in air velocity through the working air flow path through the vacuum cleaner. This type of sensor  124  can detect a clogged condition of the filter media  88 , i.e. when the exposed portion  98  becomes so soiled that air flow through the filter assembly  60  is inhibited. Another example of a suitable sensor  124  is a pressure sensor that detects a drop in pressure in the working air flow path through the vacuum cleaner, which also detects a clogged condition of the filter media  88 . In yet another example, the sensor  124  can detect an operating time of the vacuum cleaner, and be configured to prompt the user to replace the filter media  88  after a predetermined operating time has elapsed. 
         [0030]      FIG. 6  is a cross-sectional view through a separation module  26  according to a second embodiment of the invention. The second embodiment of the separation module  26  can be substantially similar to the first embodiment, and like elements are referred to with the same reference numerals. The second embodiment of the separation module  26  can be used with the vacuum cleaner  10  shown in  FIG. 1 , and differs from the first embodiment in that the filter advancing mechanism  114  is automated. The sensor  124  can be coupled to the automatic filter advancing mechanism  114  and can trigger the mechanism  114  to automatically index the take-up reel  108  when the exposed portion  98  of the filter media  88  needs to be replaced. One example of a suitable automatic filter advancing mechanism  114  comprises a motor  128  coupled to the take-up reel  108 . The motor  128  can have a drive shaft  130  which is coupled to the gear train  116  to drive the drive gear  120  when the motor  128  is activated by the sensor  124 . 
         [0031]    The motor  128  can be supported by the bottom cover  64 , or elsewhere within the separation module  26 . In one example (not shown), the automatic filter advancing mechanism  114  can be positioned near the top of the separation module  26 , with the filter assembly  60  depending therefrom, such that the filter assembly  60  can be removed from the separation module  26  without removing the motor  128 . In this example, the drive shaft  130  of the motor  128  can releasably couple with the gear train  116  to selectively attach or remove the filter assembly  60  from the separation module  26 . 
         [0032]    While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. For example, while the filter assemblies illustrated herein are shown mounted within the separation chamber of a single stage cyclone separator, it is understood that the filter assemblies could be applied to a dual stage separator, multiple parallel first and/or second stage, or additional downstream separators, or other types of cyclone separators. Moreover, the filter assemblies could be mounted downstream from the cyclone separator or suction source. Reasonable variation and modification are possible with the scope of the foregoing disclosure and drawings without departing from the spirit of the invention which, is defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.