Abstract:
A dirt separation and collection assembly suitable for use in a bagless vacuum cleaner including two dirt separation and collection zones is provided. Dirty air enters the upper portion of a container and enters a first stage dirt separation zone including a disruptor ring extending inwardly from the outer wall to allow coarse dirt particles and fibers to pass through and collect at the base of the outer wall of the device. The spinning air is then drawn through a conical shroud and fed into a second stage conical separator for separating fine dirt particles and collecting them in an inner substantially cylindrical collection chamber. Air exits the conical separator at the opposite cone opening before being drawn to the suction source. Elements may be oriented upwardly or downwardly depending upon the configuration of the housing for receiving the dirt separation and collection assembly.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     This invention relates to dirt separation and collection devices and, more particularly to a vacuum cleaner including a dirt cyclonic separation and collection assembly having a first separation zone with a decoupling ring for separating and collecting coarse dirt particles and a second stage separating zone including a frusto-conical cyclone for separating and collecting fine dirt particles.  
         [0002]     Cyclonic vacuum cleaners have been known for some time. For example, European Patent No. EP 0 042 723 and U.S. Pat. No. 4,593,429 to James Dyson disclose a vacuum suction cleaning device including two cyclone units in series operating successively to extract dirt particles from an air flow. One of the two cyclones has a substantially frusto-conical shape serving to increase the velocity of the dirt particles so that the cyclone is capable of depositing the fine dust particles in a small diameter collection chamber relative to the diameter of the cone opening. Prior to the air entering the cyclone, dirty air enters tangentially against the wall of a cylindrical outer chamber operating as a cyclone to remove coarse dirt particles from the dirty air entering the device.  
         [0003]     In addition to devices wherein the successive cyclones are coaxial as in the above noted publications, Dyson in U.S. Pat. No. 4,373,288 places frusto-conical cyclones side by side. In this configuration, the device is designed to remove dirt through the two cyclones operating in series. The principal objective in all these devices is to avoid the need to utilize a bag as in conventional vacuum cleaners. In these conventional devices, air is drawn through the appliance by a fan that creates a large pressure drop as the bag fills with dirt. This increase in pressure drop lowers the cleaning efficiency of the unit. It is for this reason that configurations for bagless vacuum cleaners are extremely appealing.  
         [0004]     A bagless cleaning device is disclosed in WO 99/42198 based on PCT/GB99/00507 by the applicant herein. The full text of this publication is incorporated herein by reference. In this device dirty inlet air is passed into the upper portion of a cyclone having a cylindrical cross-section and a lower frusto-conical section. This cyclone separation stage is designed to separate fine dirt particles in a collection chamber below the cone opening. The cylindrical portion of the device includes a transition zone connected to an adjacent side chamber for collection of coarse dirt particles. In another embodiment disclosed therein, coarse dirt is collected in an outer larger cylindrical chamber surrounding the inner frusto-conical cyclone separator.  
         [0005]     Other bagless vacuum cleaner designs are shown in a series of related applications that issued to Royal Appliance Mfg. Co. based on an application that initially issued as U.S. Pat. No. 6,003,196 on Dec. 21, 1999. These patents disclose various types of upright vacuum cleaners including an air separation chamber that may be a cyclonic separation device. All the vacuum cleaners described in these patents include a filter disposed in the cyclonic air flow chamber or dirt cup upstream of the suction source.  
         [0006]     U.S. Pat. No. 6,192,550 to Sanyo Electric Co., Ltd. also discloses a vacuum cleaning device having a rotatable filter disposed in a cyclonic air separation chamber. This device is particularly effective, because the rotatable feature of the filter allows removal of dirt entrained in the filter into the bottom of the dirt cup for easy disposal when the dirt cup is removed for cleaning. The contents of this patent are incorporated herein by reference.  
         [0007]     While many of these bagless designs are improvements over conventional vacuums utilizing bag technology, it remains desirable to provide continued improvements and alternative designs to improve the separation of dirt particles from air without the need to include filters in the air separator chamber or in the dirt cup.  
       SUMMARY OF THE INVENTION  
       [0008]     Generally speaking, in accordance with the invention, a dirt separation and collection assembly for a vacuum cleaner including a first substantially cylindrical separation zone with a decoupling ring is provided. The separation and collection assembly has an elongated cylindrical container including the cylindrical separation zone with an inlet at the upper region and a decoupling ring or short section of an inverted frusto-conical cone positioned mid-way down the container wall at the lower and of the separation zone. A second stage fine dust separating cyclone maybe coaxially mounted within the cylindrical container with a conical shroud surrounding the cone to allow air to travel to the large cone opening. The cylindrical separator removes coarse dirt particles from the dirty inlet air before the air is fed into the fine dirt cyclone separator.  
         [0009]     Dirty air enters tangentially into the interior of the upper portion of the air separation zone and travels down the container wall until the air reaches the decoupling ring. Here, the air is directed off the inner wall and passes through a conical shroud disposed about the inner conical cyclone. Coarse dirt and fibrous materials pass through the space between the decoupling ring and shroud. Dirt removed from the air flow is deposited in the bottom of the container. Air then enters the larger cone opening to the interior of the inner conical separator wherein fine dirt particles are removed through the smaller cone opening at the opposite end and clean exhaust air is withdrawn at the center of the larger cone opening.  
         [0010]     Accordingly, it is an object of the invention to provide an improved dirt separation and collection assembly for a vacuum cleaner that provides greater dirt separation over existing designs.  
         [0011]     It is another object of the invention to provide a dirt separation container including a cylindrical separator with a decoupling ring or inverted conical section mounted on the inner wall of the container.  
         [0012]     It is a further object to the invention to provide a separation and collection container having a second stage fine frusto-conical separation disposed coaxially within the cylindrical container.  
         [0013]     Yet another object of the invention is to provide a dirt separation container including a frusto-conical shroud with holes about an inner cyclonic separator for directing air to the large cone opening of the conical separator.  
         [0014]     Still another object of the invention is to provide a shroud for dirt separation container including a plurality of holes angled in the direction of air flow about the shroud.  
         [0015]     Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.  
         [0016]     The invention accordingly comprises the features of construction, combination(s) of elements, and arrangement of parts which will be exemplified in the construction(s) hereinafter set forth, and the scope of the invention will be indicated in the claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]     For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawing(s), in which:  
         [0018]      FIG. 1  is a side sectional view of an upright vacuum cleaner of the type disclosed in the prior art including a filter within a removable cylindrical cyclonic air separation and collection chamber;  
         [0019]      FIG. 2  is a front sectional view of the upright vacuum cleaner illustrated in  FIG. 1 ;  
         [0020]      FIG. 3  is a perspective view of a dirt separation and collection assembly with a clear substantially cylindrical side wall with an inverted disrupter ring constructed and arranged in accordance with the invention;  
         [0021]      FIG. 4  is a sectional view of the air separation and collection assembly of  FIG. 3 ;  
         [0022]      FIG. 5  is an exploded view of the elements of the dirt separation and collection assembly of  FIGS. 3 and 4 ;  
         [0023]      FIG. 6  is an exploded view of the shroud and fine dirt separation assembly of  FIGS. 3-5 ; and  
         [0024]      FIG. 7  is a cross-sectional view of an air separation and collection assembly as shown in  FIG. 1  with vanes below the disrupter ring in accordance with another embodiment of the invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]      FIGS. 1 and 2  illustrate a side sectional view and a front sectional view of the upright vacuum cleaner of the type shown in U.S. Pat. No. 6,192,550, the disclosure of which is incorporated herein by reference. Here, a suction nozzle  2  for floors is formed at a lower portion of a main body  1  of the vertical type vacuum cleaner with a handle  3  for operating main body  1  at an upper portion thereof, all of which are formed in an uniform manner.  
         [0026]     Suction nozzle  2  for floors has a suction inlet  4  at a bottom surface side and further incorporates therein a rotating brush  5  to face suction inlet  4 . Rotating brush  5  is connected to a rotating shaft of a motor fan  6  that is incorporated in the lower portion of main body  1  to be driven in a rotating manner. A pair of laterally arranged front wheels  7  are attached frontward of the bottom surface of suction nozzle  2  for floors, while a pair of laterally arranged rear wheels  8  are attached rearward of a lower portion of main body  1 .  
         [0027]     A pipe  9  is attached on either side of the suction nozzle  2  for floors that communicates with suction inlet  4 . Pipe  9  extends upward along main body  1  to a tip end portion of a hose  10  in a freely attachable and detachable manner. Hose  10  is disposed to the rear surface side of the main body  1  by means of a holding portion  11  arranged on a rear surface side of the handle  3  for operating the main body and is connected to a suction cylinder  12  which is formed to be shifted to either side with respect to a center of the rear surface side.  
         [0028]     A dust-collecting device (dust-collecting unit)  20  is fitted to a central portion on the front surface side of the main body  1  of the vacuum cleaner in a freely attachable and detachable manner. Dust-collecting device  20  includes cylindrical pre-filter  22  made of transparent resin or the like fitted into the interior of a substantially cylindrical dust-collecting case  21  made of transparent resin or the like, with a substantially cylindrical main filter  23  inside of pre-filter  22 .  
         [0029]     Dust-collecting case  21  is provided with a grip  24  at a central portion on a side that faces to the front when being attached to main body  1 . Grip  24  is so arranged as to extend in a longitudinal direction in a successive manner downward to handle  3  for operating main body  1  with a groove  25  is formed on a surface of the grip  24 .  
         [0030]     A handle  26  is rotatable for rotating the pre-filter  22  that is attached to an upper side of grip  24  in such a manner that it is freely foldable in a transverse direction with respect to a rotating axis  27  thereof. Handle  26  can be accumulated in groove  25  of grip  24  while a knob  26   a  of handle  26  is fitted to a concave portion  25   a  formed in groove  25  of grip  24  to be fixed thereat. It is possible to discharge dust accumulated within dust-collecting case  21  by holding grip  24 , and the handle  26  can also be accumulated by efficiently utilizing the grip  24  which is not needed at the time of performing cleaning.  
         [0031]     A clamp  28  is engaged with main body  1  when dust-collecting device  20  is fitted to main body  1  is provided on an upper side of the handle  26  of the dust-collecting device  20 .  
         [0032]     A bottom lid  32  is attached which is arranged to be freely openable and closeable by a hinge  31  provided in a lower portion of grip  24 . Bottom lid  32  is so arranged that by pushing a lever  33  provided in a lower portion of the grip  24 , a clamp  34  formed on an opposing side of the dust-collecting case  21  to be connected to the lever  33  is disengaged from an engaging jaw  35  to thereby release a discharge outlet  36  for the dust.  
         [0033]     A spiral rib  52  is formed as to extend in vertical directions on an outer periphery of the pre-filter  22 . The spiral rib  52  is disposed about pre-filter  22  so that dust which has accumulated and compressed within dust-collecting case  21  is pushed out in a direction of the discharge outlet when bottom lid  32  is opened for rotating the filter is rotated in a rightward direction.  
         [0034]     Air that has been filtered of dust within dust-collecting device  20  exits through the aperture on the lower portion side of cylindrical body  40  of main filter  23  to the exterior of dust-collecting case  21 . Filter air is taken in by motor fan  6  via a filter  56  shown in  FIG. 1  to be exhausted through an exhaust outlet  58  formed on a lower portion of a front surface of main body  1  to the exterior by being passed from motor fan  6  through an exhaust filter  57 .  
         [0035]     Dust which has been scraped up by rotating brush  5  of the suction nozzle  2  for floors passes through pipe  9  and hose  10  into dust-collecting case  21  through suction cylinder  12  located to be shifted in either direction with respect to a center of the rear surface side of main body  1  and is made to flow downward by being revolved along the inner wall thereof while large-sized dirt particles (coarse dirt) are deposited on the bottom.  
         [0036]     Mesh  51  of pre-filter  22  for sucking air is formed to be located downward within dust-collecting case  21 . Dust that has entered together with air through suction hole  30  located upward within the dust-collecting case  21  is pushed downward by being revolved at a high speed so as to be deposited on the bottom surface (bottom lid  32 ) of dust-collecting case  21  in a pressed condition.  
         [0037]     Further, small-sized dust particles (minute dust) enters into pre-filter  22  by passing through mesh  51  arranged in the lower portion of pre-filter  22  and is filtered by the pleat-like main filter  23 . Thus, only clean air enters main filter  23  to flow downward through the motor fan  6  to be finally exhausted through the exhaust outlet  58  to the exterior.  
         [0038]     Discharge of dust which has been accumulated in the dust-collecting case  21 , by holding grip  24  of dust-collecting case  21  and drawing the case out with pushing an operating portion of clamp  28  disposed above the grip  24  upward, the dust-collecting case  21  is detached from the main body  1  of the vacuum cleaner.  
         [0039]     By pushing a lever  33  provided in the lower portion of the dust-collecting case  21 , clamp  34  is detached whereby bottom lid  32  is released to enable discharge of dust that has been accumulated in dust-collecting case  21 . At this time, especially flock-like dust adheres to the inner wall of dust-collecting case  21  in a compressed state so that dust does not easily come off as it is. Thus, handle  26  is rotated in a specified direction (in this case in a rightward direction) for rotating pre-filter  22  in a specified direction whereby spiral rib  52  provided on outer periphery of pre-filter  22  acts to push out dust such as flock-like dust in a compressed state so that easy discharge is enabled.  
         [0040]     In an effort to eliminate the need for a filter in the air separation and collection chamber in the type of upright vacuum shown in  FIGS. 1 and 2 , a dirt separation and collection assembly  101  as shown  FIG. 3  constructed in accordance with the invention may be substituted for dust collecting case  21  in a vacuum cleaner, such as main body  1 . The individual elements in dirt separation and collection assembly  101  are shown in  FIGS. 4-6 .  
         [0041]     Referring now to  FIG. 3 , dirt separation and collection assembly  101  includes a cylindrical container  102  formed with a substantially cylindrical sidewall  103 , a selectively openable bottom  104  and a cover  106  . Bottom  104  is secured to sidewall  103  by a hinge  107  and is opened by a latch  108  for cleaning in the same manner as described in connection with the vacuum cleaner of  FIGS. 1 and 2 . A dirty air inlet  109  is provided at the upper portion of sidewall  103 .  
         [0042]     A decoupler or disrupter ring  111  is positioned on the inside of sidewall  103  about mid-way along its height. Ring  111  is in the form of a short inverted frusto-conical projection having a lower opening  112  a portion of the distance from sidewall  103 . Disrupting ring  111  and cover  106  define an air separation zone  113  within container  102 . A frusto-conical shroud  116  surrounding a conical separation  117  shown in  FIG. 4  is disposed on the axis of container  102  in zone  113 . Ring  111  projects into cylinder  102  between about 20 to 50% of the annular distance between sidewall  103  and shroud  116 . A coarse dirt collection region  114  is formed at the bottom of container  102  and is defined by a central column  118 , sidewall  102  and bottom  104 .  
         [0043]     Dirty air enters assembly  101  through inlet  109  in sidewall  103  and enters tangentially along sidewall  103  in air separation zone  113 . Disrupter ring  111  causes circulating air to be lifted off sidewall  103  and coarse dirt to be collected in outer collection region  114 . Second stage fine dirt separation zone  125  shown in  FIG. 4  is coaxially disposed in container  102  with center column  118  in which fine dirt particles are collected in a second collection region  119  defined by column  118  and bottom  104 .  
         [0044]      FIG. 4  is a cross-sectional view of second stage shroud  116  and cyclone  117 . Shroud  116  and cyclone  117  are inverted frusto-conical in shape with a space  121  therebetween. Shroud  116  has a plurality of holes  120  (shown in  FIG. 6 ) to allow air to enter space  121  between shroud  116  and the outer side of cone  117 .  
         [0045]     Cone  117  has a large upper cone opening  122  and a lower small cone opening  123 . Similarly shroud  116  has a large upper cone opening  124  and a lower smaller cone opening  126  terminating at the top of central column  118 . A gasket  127  is provided at the top of column  118  to isolate space  121  from collection region  119  and isolate the inner region of cone  117  from air separation air  113 .  
         [0046]     A plurality of inlet vanes  130  for feeding air to the interior of cyclone  117  are placed between shroud opening  124  and cone opening  122 . Cyclone  117  is mounted on central column  118  by gasket  127 . Shroud  116  is conical in shape and configured to fit over cyclone  117  and provide a passage for air to flow through holes  120  to vanes  130  before entering conical separator  117 .  
         [0047]     Cyclone  117  extends from the top of container  102  to a point about three quarters of the height of container  102  with large cone opening  122  at the top and small cone opening  123  at the bottom. A deflector plate  128  is mounted at small cone opening  123  supported by at least one rib  129 .  
         [0048]     Shroud  116  extends downwardly to gasket  127  that fits snugly into column  118 . Gasket  127  includes an outwardly extending skirt  131  below disrupter ring opening  112 .  
         [0049]      FIG. 5  is an exploded view of assembly  101  showing cylindrical container  102 , bottom  104 , hinge  107 , latch  108 , shroud  116 , inlet  109 , and cover  106 .  
         [0050]      FIG. 6  is an exploded view of the elements of shroud  116  and conical separator  117 . Vanes  130  are shown at top opening  122  of cone  117 . Shroud  116  is assembled from four shroud plates  131  mounted on a shroud frame  138 . Holes  120  in shroud plates are angled in the direction of air flow in separation zone  113  to facilitate passage into space  121 . This also reduces collection of fine dirt on shroud  116  and in holes  120  of shroud  116  during operation.  
         [0051]      FIG. 7  is a cross-sectional view of a modification of assembly  101 . Here, a plurality of vanes  151  are disposed on container wall  103  below disrupter ring  111 . All the remaining elements of assembly  101  are present in this embodiment. Air entering the first stage separator rotates in space  113  between sidewall  103  and shroud  116  with large dirt particles passing through the space between ring  111  and skirt  131 . These particles are collected on base  104  in region  114 . Paddles or baffles may be placed on the inside surface of base  104  to prevent re-entrainment of dirt during operation of the separation device.  
         [0052]     Air circulating in first stage separator zone  113  passes through holes  120  (shown in  FIG. 6 ) in shroud  116 . It then travels upwardly to a series of directional vanes  130  and is directed into a second stage frusto-conical separator  117  coaxially oriented within container  102 . Second stage conical separator  117  has a large cone opening  122  at the top and a smaller cone opening  123  at the bottom. The separation elements may be oriented in any direction.  
         [0053]     Air then rotates downwardly along the inside wall of cone  117  and then turns upwardly to exit through an outlet  133  and passes through exhaust or outlet conduits on the outside of vessel  102 . Fine dirt is expelled through lower cone opening  123  and collected in collection zone  119  at the base of column  118 . Exiting clean air then passes through a filter, such as a HEPA filter, to a suction source such as motor fan  6  in the vacuum cleaner of  FIG. 1 . A deflector plate  128  may be placed at the outside of small cone opening  123  to increase efficiency of the separation in conical separator  117 .  
         [0054]     In the embodiment illustrated in  FIGS. 3-7 , holes  120  in shroud  116  are angled at about 45°. The more tangential the angle, the better, but generally between about 30 to 75 degrees.  
         [0055]     During operation coarse particles and fibers are separated from the dirty inlet air in first stage separator  113 . These coarse particles are collected in the base of vessel  102 . Fine dirt particles separated in second stage cyclonic separator  125  are collected in second stage collection zone  119 .  
         [0056]     Dirt separation and collection assembly  101  is interchangeable and usable with the type of vacuum cleaner as illustrated in  FIGS. 1 and 2 . In addition, assembly  101  may be used with a stick vacuum or a canister vacuum cleaner. Here, dirty air enters towards the middle to upper portion of vessel  102  and exits through cap  106  and is transported to motor fan  6  at the base of main body  1 .  
         [0057]     It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.  
         [0058]     It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention that as a matter of language, might be said to fall therebetween.