Abstract:
A cyclonic separation device in accordance with an embodiment of the present application preferably includes a first cyclone chamber having a cylindrical shape with a predetermined diameter, the first cyclone chamber including, a tangential inlet positioned on a first longitudinal end of the first cyclone chamber, a baffle plate positioned in the first cyclone chamber a predetermined distance from the tangential inlet, a tangential dirt outlet positioned on a second end of the cyclone chamber, opposite the inlet and on an opposite side of the baffle plate from the tangential inlet and a center exit duct mounted in the center of the cyclone chamber having an inlet opening positioned upstream from the baffle plate such the centrifuged fluid without particles flows into the center exit duct and out of the cyclone chamber.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. nonprovisional application Ser. No. 12/074,438 filed Mar. 8, 2008 entitled CENTRIFUGAL DIRT SEPARATION CONFIGURATIONS FOR HOUSEHOLD-TYPE AND SHOP-TYPE VACUUM CLEANERS which claims benefit of and priority to U.S. Provisional Patent Application Ser. No. 60/892,723 filed Mar. 2, 2007 entitled CENTRIFUGAL DIRT SEPARATION CONFIGURATIONS FOR HOUSEHOLD-TYPE AND SHOP-TYPE VACUUM CLEANERS, the entire contents of which are hereby incorporated by reference herein. 
    
    
     BACKGROUND 
     1. Field of the Disclosure 
     The present application relates to an apparatus for separating dirt or dust particles from an air flow by cyclonic means. The application relates particularly, but not exclusively, to a cyclonic dust separation apparatus for use in a vacuum cleaner. 
     2. Related Art 
     Cyclone dust separation devices typically include a frusto-conical (truncated cone) cyclone having a tangential air inlet at the one end having a large diameter and a cone opening leading to a dirt or dust collection area at the other end which has a smaller diameter. 
     There are numerous patents describing a variety of bagless vacuum cleaners now on the market by manufacturers such as Dyson, Hoover, Bissell; i.e. U.S. Pat. Nos. 5,858,038; 5,062,870; 5,090,976; 5,145,499; 6,261,330 and 5,853, 440; English Patent Pub. No. GB727137; and French Patent Pub. No. FR1077243. 
     U.S. Pat. No. 6,261,330 discloses a device including a fan for causing fluid to flow through the cyclone separator, the cyclone separator having an inlet and an interior wall having a frusto-conical portion tapering away from the inlet, wherein the fan is positioned in the inlet to the cyclone separator chamber on the same axis thereof, such that fluid passing through the fan is accelerated towards the interior wall, and thereby, given sufficient tangential velocity to cause cyclonic separation of particles from the fluid flow within the cyclonic separator chamber. The fan motor is located on the centerline of the cyclone separator chamber, and thus, adds to the size of the cyclone separator chamber. 
     In U.S. Pat. No. 6,261,330, the inlet port arrangement and the concentric exit port connectors to the cyclone separator are not optimum. The cyclone chamber depends on gravity to keep the dirt in the bottom of the collection chamber, thus requiring the suggested alternate configuration in which the motor is connected to the fan by a long shaft that extends through the cyclone chamber to the fan at the top of the chamber. This position is not ideal for providing suction to lift dirt from the floor. The patent contends that this is an advantageous design because it lowers the center of gravity of the device as a whole when compared to the embodiment shown with the motor at the top of the vertical cyclone separation chamber. 
     Since many standard vacuum cleaner motors now run at very high RPM&#39;s (22,000 RPM, for example) they provide good airflow and vacuum performance with reduced weight. Having a long shaft through the cyclone separator chamber, however, as suggested by the referenced patent, would not be ideal since shaft critical speed vibration problems are likely to result, thus preventing any weight reduction options to improve the desirability of the vacuum cleaner for the public use. 
     All of the cyclonic separator type vacuum cleaners now on the market have their cyclone separator chamber on the suction side of the fan so that they are driven by the air flow that is being sucked through them. This has the advantage of only clean air being pulled through the fan impeller, but provides much less velocity and energy than would be available by placing the cyclone separation chamber on the discharge side of the vacuum fan. 
     Accordingly, it would be desirable to provide a cyclonic dust separation device, preferably suitable for use in a home vacuum cleaner that avoids the problems discussed above. 
     SUMMARY 
     It is an object of the present invention to provide an apparatus for separating particles from a fluid flow having a cyclone separator which is efficient, compact, lightweight, and easy to service and maintain. 
     A cyclonic separation device in accordance with an embodiment of the present application preferably includes a first cyclone chamber having a cylindrical shape with a predetermined diameter, the first cyclone chamber including, a tangential inlet positioned on a first longitudinal end of the first cyclone chamber, a baffle plate positioned in the first cyclone chamber a predetermined distance from the tangential inlet, a tangential dirt outlet positioned on a second end of the cyclone chamber, opposite the inlet and on an opposite side of the baffle plate from the tangential inlet and a center exit duct mounted in the center of the cyclone chamber having an inlet opening positioned upstream from the baffle plate such the centrifuged fluid without particles flows into the center exit duct and out of the cyclone chamber. 
     The cyclonic separation device of the present application may be used in a variety of applications, including, but limited to use in centrifugal separation type vacuum cleaners. 
     A vacuum cleaner in accordance with an embodiment of the present invention preferably includes a handle and a floor housing to which the handle is pivotally connected. The floor housing preferably includes a suction fan motor, a suction fan driven by the motor and including a plurality of fan blades driven at a high velocity by the suction fan motor to suck a fluid from a first side of the fan to the second side of the fan, a pick up head positioned adjacent to a floor and in fluid communication with the suction fan and a cyclonic separator device. The cyclonic separator device includes a first cyclone chamber having a cylindrical shape with a predetermined diameter, the first cyclone chamber including a tangential inlet positioned on a first longitudinal end of the first cyclone chamber, a baffle plate positioned in the first cyclone chamber a predetermined distance from the tangential inlet, a tangential dirt outlet positioned on a second end of the cyclone chamber, opposite the inlet and on an opposite side of the baffle plate from the tangential inlet; and a center exit duct mounted in the center of the first cyclone chamber having an inlet opening positioned upstream from the baffle plate such the centrifuged fluid without particles flows into the center exit duct and out of the first cyclone chamber, wherein the pick up head and suction fan are connected in fluid communication with the first cyclone chamber such that fluid flows from the pick up head through the tangential inlet into the first cyclone chamber and rotates therein at high velocity such that particles in the fluid are forced out to the inner surface of an outer wall of the first cyclone chamber and beyond the baffle plate to be discharged through the dirt discharge outlet. 
     A vacuum cleaner in accordance with another embodiment of the present invention preferably includes a handle and a floor housing to which the handle is pivotally attached, The floor housing preferably includes a suction fan motor, a suction fan, driven by the motor, a first cyclone separator connected to an inlet of the suction fan. The first cyclone separator preferably includes a first cyclone chamber having a cylindrical shape with a predetermined diameter, the cyclone chamber including a tangential inlet positioned on a first longitudinal end of the first cyclone chamber, a baffle plate positioned in the chamber a predetermined distance from the tangential inlet, a tangential dirt outlet positioned on a second end of the cyclone chamber, opposite the inlet and downstream of the baffle plate, a center exit duct mounted in the center of the cyclone chamber having an inlet opening positioned downstream from the baffle and in fluid communication with the suction fan inlet such that rotation of the suction fan draws fluid into the first cyclone chamber to rotate at high velocity forcing particles in the fluid past the baffle plate and out of the tangential dirt outlet and a removable dirt collector in fluid communication with the tangential dirt outlet and structured to store the particles discharged from the tangential dirt outlet. 
     Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING(S) 
         FIG. 1  illustrates an upright floor sweeper vacuum cleaner in accordance with an embodiment of the present application 
         FIG. 2  shows a top view of the vacuum cleaner described for  FIG. 1 . 
         FIG. 3  shows a front view of the conceptual configuration of  FIG. 1 . 
         FIG. 4  shows a cross sectional side view of the upright floor sweeper of  FIG. 1 . 
         FIG. 5  shows a schematic type top view of the vacuum shown in  FIG. 4 . 
         FIG. 6  shows a perspective schematic type view of a basic pressure driven cyclone separator for use with the vacuum cleaner of  FIG. 1 . 
         FIG. 7  shows a schematic type side view of a basic pressure driven compact cyclone separator for use with the vacuum cleaner of  FIG. 1 . 
         FIG. 8   a  shows a partial cross sectional perspective flow drawing of a bank of small diameter cyclone separators for a secondary separator for use with the vacuum cleaner of  FIG. 1 . 
         FIG. 8   b  is a top view schematic of  FIG. 8   a.    
         FIG. 9  shows a cross section of a floor sweeper upright type vacuum including the secondary separator of  FIG. 8 . 
         FIG. 10   a  illustrates an alternative embodiment of a vacuum cleaner in accordance with the present invention. 
         FIG. 10   b  illustrates another alternative embodiment of a vacuum cleaner in accordance with the present invention. 
         FIG. 11   a  shows the vacuum cleaner of  FIG. 10   a  with a bottom dirt collector removed. 
         FIG. 11   b  shows the vacuum cleaner of  FIG. 10   b  with a bottom dirt collector removed. 
         FIG. 12  shows an alternative embodiment of a primary cyclone separator of the vacuum cleaner of  FIG. 1 . 
         FIG. 13  shows a side view of an embodiment of a primary cyclone separator for the vacuum cleaner of  FIG. 1 . 
         FIG. 14   a  shows an alternate configuration of the vacuum cleaner of  FIG. 10 . 
         FIG. 14   b  shows the vacuum cleaner of  FIG. 14   a  with the dirt bag removed and the retention spring rolled back. 
         FIG. 15  is an exemplary illustration of a HEPA type very small particle filter for use with the vacuum cleaner of the present application. 
         FIG. 16  illustrates another exemplary embodiment of a vacuum cleaner in accordance with the present application. 
         FIG. 17  shows a bottom view of the vacuum cleaner of  FIG. 16  without a bottom cover. 
         FIG. 18  shows an external view of the bottom of the vacuum cleaner of  FIG. 17  with the bottom cover in place. 
         FIG. 19  shows cross sectional side view of the vacuum cleaner of  FIGS. 16-18 . 
         FIG. 20  shows a more detailed view of the primary cyclone separator of the vacuum cleaner of  FIGS. 16-19 . 
         FIG. 21  shows an alternative embodiment of the primary cyclone separator of  FIG. 20 . 
         FIG. 22  shows a secondary cyclone separator suitable for use in the vacuum cleaner of  FIG. 16 . 
         FIG. 23  illustrates a vacuum cleaner in accordance with another embodiment of the present application. 
         FIG. 24  shows an illustration of a high performance cyclone separator of the concept illustrated in  FIG. 6  applied to replace a cleanable filter cloth in a central vacuum system in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     The theory of cyclone dirt or dust separation suggests that efficiency can be increased by increasing the tangential velocity of the air in the separation chamber. This would typically suggest providing a more powerful motor to create a higher rate of fluid flow. However, there are limits to the size and weight of motors that the market will tolerate for domestic vacuum chambers, since the size and weight of these chambers naturally influences the size and weight of the resulting domestic home vacuum cleaner as a whole. Increased complexity and size also add to the cost of the vacuum cleaner, which is also an important consideration in the competitive home vacuum cleaner market. 
     Thus, reducing the size of the motor required to provide a simple high efficiency domestic home vacuum cleaner or shop vacuum cleaner is very desirable. Smaller, lighter weight, more energy efficient vacuum cleaners provide significant advantages in such a competitive market. The vacuum cleaner of the present application allows for a reduction in motor size in that it preferably provides the dirt separation chamber on the output, or blowing, side of the suction fan, which allows the suction fan to impart more speed to the dirt laden air as it is provided to the separation chamber. Thus, higher speed air is provided in the separation chamber without the need to use a larger motor. In addition, the diameter of the separation chamber may also be reduced, which also aids in maintaining high velocity air flow therein and provides better separation while reducing overall vacuum size. These features are described in further detail below. 
     In the vacuum cleaner  1  (See  FIG. 1 ), for example, of the present application, the design of the fan motor and fan can be separately optimized while maintaining proper motor cooling. Further, the vacuum cleaner of the present application is preferably buildable using existing highly developed domestic vacuum cleaner motors now in production. In addition, the incoming flow to the fan impeller does not have to be compromised and the cyclonic separating chamber can be optimized separately without the need to compromise its design for motor or fan considerations, as is the case in the prior art discussed above. 
     The design of the present application minimizes the opportunities for flow passage blockage that is a problem in other cyclone dirt separation vacuum cleaners now on the market since all of the air flow elements are preferably close connected with minimum duct work and high velocity air. This reduces the opportunity for velocity and pressure drops as air flows through the cleaner. 
       FIG. 1  illustrates a conceptual perspective view of an upright type vacuum floor cleaner  1  in accordance with an embodiment of the present application. The cleaner  1  includes a handle assembly  4  which can be pivotally mounted to the side of the vacuum cleaner housing assembly  5  which is partially carried by rear wheel assembly  7  and whose pick up head  9  rides in close proximity to a carpet or floor. The head area  9  preferably includes small rollers (not shown) mounted under the housing  5  as well. 
     The vacuum cleaner suction fan and motor assembly  20  generates suction that is connected to the head area  9  of the vacuum cleaner  1 . The suction lifts dirt and dust from the floor and into the vacuum  1 . This dirt-laden air then passes through the motor driven fan  6  (See  FIG. 4 ) and is accelerated by the high velocity of the fan rotor blades  8 . In a preferred embodiment, the velocity of the blades  8  may be almost the speed of sound (1100 ft/sec) such that the air and dirt is thrown through the tangential input connecting duct  11  to the primary cyclone separator  22 . The primary cyclone separator  22  preferably includes a relatively small diameter cyclone chamber  10  (preferably approximately 4 inches in diameter) where the dirt is moved against the outside walls by the very high centrifugal forces and passes the baffled plate  12  (See  FIGS. 6 and 7 ) to be discharged tangentially from the chamber  10  through tangential dirt outlet  23  into a dirt collection bag or container  14 . 
     The dirt free air, however, moves towards the center of the cyclone chamber  10  and exits through a central duct  16  where it can then be finally filtered by filter  18 , if desired, or run through a secondary cyclone separator  65  which preferably includes a group of small diameter cyclone chambers  60  which generate very high g-forces due to their smaller diameter. 
     It is preferred that the air velocity remain high and that the components of the cleaner  1  are closely coupled together to provide for minimum pressure drop between components and to maintain a very open flow design. 
     The secondary cyclone separator  65  is shown in more detail in  FIGS. 8   a  and  8   b , and is preferably embodied as a group of small diameter tangential entry chambers  60  on top of truncated cones  62  that taper to a decreased radius for increasing centrifugal force and including truncated opening  63  at the bottom thereof to provide for dirt discharge into a separate, very fine dirt collection chamber  64 . This chamber  64  can also be separately cleaned less often than the larger dirt collection chamber  14 . The dirt exit, or openings  63  of each of the small truncated cones  62  can have a reverse cone shape to spread the spinning dirt outwardly and allow more separation between the discarded dirt and the returning air circulation at this location. Air preferably enters the chambers  60  via the inlets  61   
     The primary, first, cyclone chamber  10  removes all of the larger dirt and a large part of the smaller dirt because of its high velocity, before the air is discharged into these small diameter chambers  60  through connecting duct openings which allow them to operate at maximum efficiency. Thus, the primary cyclone chamber  10  effectively deals with the larger, more voluminous dirt by discharging it into a large collection container  14  which can be several times the capacity of the low efficiency cyclone first stage chamber of bag-less vacuum cleaners now on the market since they have to capture the large dirt in the lower part of their cyclone chamber and provide sufficient space to accommodate dirt storage and cyclonic separation. In contrast, in the cleaner  1 , for example, of the present application, the dirt is discharged tangentially from the primary cyclone chamber into a separate container for dirt storage. Thus, the size of the primary cyclone chamber is reduced and this provides improved efficiency. Dirt storage can be increased as well, since a separate chamber is provided for the separated dirt, this chamber can be rather large which allows the chamber to be emptied less often. It is noted that the dirt collection chamber  14  is preferably removably attached to the cleaner  1  to allow it to be easily removed and emptied. 
     The secondary cyclone section  65  has high efficiency and includes a plurality of small diameter cyclone chambers  60  which are left to function in their optimum condition with comparatively clean air, i.e. air only including particles with a diameter of 50 microns. 
     The air can then be withdrawn centrally from each of the second stage high efficiency cyclones chambers  60  via the ducts  70  and exhausted, if desired, through exit duct  80  to HEPA filter  18 , if desired. However some, or most of this air may alternatively be returned to the vacuum pick up head  9  through the opening  13  to provide jet assisted suction at the pick up area ( FIG. 9 ). The opening  13  is preferably positioned to discharge the returned air substantially parallel to the floor, creating an area of low pressure just above the floor due to the high velocity of the returned air. This area of low pressure (i.e. Bernoulli pressure) aids in suction at the pick up head  9 . The return air is in turn sucked back into the vacuum  1  again where the cycle is repeated. In this manner, the air sucked into the cleaner  1  can be recycled to aid in further suction and separation. 
     The primary cyclone separation chamber  10  provided in the cleaner  1  of the present application preferably has a relatively small diameter (4 inches, for example) which is quite small when compared to that required when the dirt is being separated on the suction side of the vacuum fan, as in the prior art discussed above. This allows for a much more compact, lighter weight and lower manufacturing cost vacuum cleaner. Also, the configuration of the cleaner  1  ensures that the dirt is not captured at the bottom of the primary cyclone chamber, but is discharged tangentially into a bag or dirt compartment  14  separated from the cyclone chamber  10 . This, as previously stated, also allows for a reduction of the size of the cyclone separation chamber and more versatility to allow the cyclone dirt separation chamber to be used in a variety of vacuum cleaners configurations including shop vacuums or canister type vacuums, as well as carpet sweeper uprights such as that illustrated in  FIG. 1 . 
     The vacuum cleaner design of the present application also has many advantages over prior art vacuum cleaners that use disposable porous bags which must be purchased separately and require frequent replacement. These bag-type vacuums lose effectiveness as the filter bags becoming full and fine particles become trapped by the filter bag to degrade its permeability and cause a loss of suction. While vacuum cleaners using cyclonic separation chambers are known in the art and avoid the problems of replaceable bag cleaners discussed above, these cyclone separation vacuum cleaners are very large, since they must accommodate the larger separation chambers necessary to provide separation and dirt storage. 
     One of the important features of the vacuum cleaner described herein is to provide for open air flow and to separate the dirt from the air by intense centrifugal force cyclone action such that filtration is only a final back-up if necessary at all. 
     In a preferred embodiment, the vacuum cleaner  1  of the present application preferably includes a pick up head  9  with a power driven carpet brush  3  (See  FIG. 4 ). The suction fan and motor assembly  20  preferably includes an electric motor and impeller, impeller inlet and fan  6  with a tangential discharge outlet that is aligned with the tangential inlet  11  of the primary cyclone separation chamber  10  which has cylindrical walls. The dirt collection chamber  14  may be embodied as a simple non-porous bag or a separate chamber and is connected to a tangential outlet  23  of the chamber  10 . A back up filter  18  may be provided as well, if desired. A secondary cyclone separator  65  may also be provided in the discharge flow path of the primary separator chamber  10 . This secondary separator  65  is preferably optimized to remove fine particles from the air. 
     Referring to  FIG. 2  which is a top view looking down on the vacuum housing assembly  5  of the cleaner  1  of  FIG. 1 , the air flow path from the dirt pick up head  9  through the suction fan and motor assembly  20  and into the primary cyclone dirt separator chamber  10  can be seen. 
       FIG. 3  shows a front view of the cleaner  1  of  FIG. 1 .  FIG. 4  shows a cross sectional side view of the upright floor sweeper cleaner  1  of  FIG. 1  showing the direct tangential close coupled connection between the suction motor and fan rotor assembly  20  and the tangential inlet  11  to the cyclone separator chamber  10  along with the brush  3  (add to  FIG. 4 ). The brush  3  may be driven by a belt connected to the fan  6  or motor shaft (not shown).  FIG. 5  shows a schematic type top view of the vacuum shown in  FIG. 4 .  FIG. 6  shows a perspective schematic type view of the primary cyclone chamber  10  for use with the vacuum cleaner of  FIG. 1 . In particular,  FIG. 6  illustrates the exit duct  16  which allows cleaned air to exit the chamber  10 . It is noted that the separation chamber  10  of  FIG. 6 , for example may be used in a variety of applications including various vacuum cleaner configurations with the same benefits.  FIG. 7  shows a schematic type front view of the primary cyclone separator chamber  10  with tangential inlet  11  and dirt outlet  23  and with the central air exit passage  16  with inlet  24 . The baffle plate  12  separates the tangential dirt discharge area proximate the outlet  23  from the recirculation area of the chamber  10 . 
       FIG. 12  illustrates an alternative embodiment of the primary cyclone separation section  22  in which the center central air exit duct  16  include an inlet  24 , as illustrated in  FIG. 7  covered by a perforated cylinder including a plurality of small diameter holes  25  (i.e. 0.076-0.2 inches) rather than being fully open. The holes  25  provide noise isolation and prevent any large dirt or fluff from carpet being discharged from the chamber  10  during any periods of pressure fluctuation, i.e. momentary pressure fluctuations when the vacuum moves from a carpet to a bar floor. 
     In operation, the dirt-laden air enters tangential inlet  11  as shown by the airflow lines  11   a . The dirt is moved to the outer walls of the chamber  10  by the centrifugal force resulting from the high velocity of the inlet dirty air and the relatively small diameter of the chamber  10 . The centrifugal dirt separation force may be determined based on the following equation:
 
 F=w/gv   2   /r  
 
where “F” represent the centrifugal force, “w” represents the weight flow, g is a gravitational constant, “v” is the velocity of the air and “r” is the inside radius of the chamber  10 . The dirt particles move down the chamber  10  and pass the baffle plate  12  to be discharged from the chamber  10  at high velocity out of tangential outlet  23 . The outlet  23  is preferably connected to the collection chamber  14 , or to a bag to collect the dirt. The lighter air that accompanies the dirt into the chamber  14  is recirculated back as is illustrated by the line  23   c  of  FIG. 12  and into the chamber, or swirl area  27  downstream of the baffle  12  and recirculated in this area. The air flow exits the cyclone separator chamber through the holes  25  in the duct  16 . This exit air is very clean due to the high centrifugal force in the chamber  10 , which separates particles form the airflow. Only the clean air near the center of the chamber  10  is allowed to exit.
 
       FIG. 13  shows a side view of the primary cyclone separator chamber  10  with an additional perforated liner duct, or insert,  17  inserted into the duct  16  to provide sound (noise) dampening. The duct  17  is designed to provide a Helmholtz resonator effect due to its hole sizes and cavity spacing behind the liner walls to reduce the noise emitted from the cleaner  1 , for example. 
       FIG. 10   a  shows a conceptual perspective view of a canister type or shop vacuum cleaner  100  in accordance with another embodiment of the present application. The cleaner  100  preferably includes a top cover and frame  102  on which the basic vacuum cleaner elements may be mounted, including, suction fan motor and fan assembly  120 , centrifugal separator  122 , and final filter  108 . A vacuum hose (not shown) may be attached to the suction fan inlet  110 . Further, there is preferably a carrying handle  125  provided along with a lower dirt collecting housing  114 . 
       FIG. 11   a  illustrates cleaner  100  of  FIG. 10   a  without the dirt collecting housing  114  such that the mounting of the basic components  120 ,  122 ,  118 / 108  can be seen as well as the tangential inlet  111  to the centrifugal separator  122  and the suction fan tangential discharge port  116  as well as the tangential dirt discharge port  23  of the centrifugal separator  122 . 
     In  FIG. 10   b , the suction fan inlet  110  is shown connected to the inside top area of  120  of the primary dirt collection chamber  114   a  where the inlet  110   b  to the vacuum cleaner  100   b  is moved to enter the primary dirt collection chamber  114   a . This positioning allows nails or other large items of debris commonly cleaned using a shop vacuum to be collected before the air passes through the fan. In addition, if the vacuum  100   b  is used to pick up water, for example, the majority of the water will be trapped in the main container  114   a  before complete separation is achieved by the primary cyclone separation chamber. Thus, the collector chamber preferably includes low pressure side  114   a  and a fan discharge pressure side  114   b  that collects dirt or water separated from the suction air and discharged from the separator  122  out tangential discharge outlet  123  into the chamber  114   b.    
     The design of  FIG. 10   b  represents a much improved shop vacuum (or wet pick-up shop vacuum) which typically only clean air with a washable sponge or cloth filter such that the discharged air is often very dusty. Similarly, when liquid is picked up, the discharge air tends to be very wet since the filter is saturated by water still in the air that is passing through the discharge opening. 
       FIG. 11   b  shows the under side of the vacuum top assembly of  FIG. 10   b  with the container  114  removes. The motor and suction fan inlet  110  is now relocated inside the vacuum cover  120  to provide suction by inlet  110  directly into the container portion  114   a.    
       FIG. 14   a  illustrates an alternate configuration of the vacuum cleaner  100  of  FIG. 10   a  with a non-porous plastic or paper bag  86  attached to the cyclone chamber&#39;s tangential discharge  123 . The throw away bag  86  is preferably held in place with a roll spring  85  which can be rolled over the bag opening to clamp it to the tangential dirt discharge duct.  FIG. 14   b  shows the vacuum cleaner  100  with the dirt bag  86  removed and the retention spring  85  rolled back to expose slot  87  which is preferably formed on the outlet  123  to accommodate the spring  85  to keep the bag  86  in place. The shop vacuum cleaner of  FIGS. 10   b  and  11   b  may also utilize a bag as well to collect discharge dirt, if desired. The bag may be positioned in, or in place of the chamber  114   b , if desired 
       FIG. 15  is a partial sectional view of the HEPA type very small particle filter  18  that is shown on the upright floor sweeper vacuum cleaner  1  of  FIG. 1 , or on the alternative embodiment of  FIG. 22 , discussed below. The filter  18  preferably receives air discharged from the secondary cyclone separator  65  in  FIG. 1 , or to the air discharge duct of the primary or secondary separator sections of the embodiment of  FIG. 22 . The filter  18  provides for final air filtration if desired. The filter  18  preferably includes a housing  84  and an inlet  82  into which the cleaner air from the primary and secondary cyclone separation sections  22 ,  65  pass for final filtering. 
       FIG. 16  illustrates a compact, light weight cyclone (centrifugal) dirt separator, bagless re-circulated air and sound suppressed vacuum cleaner  200  in accordance with an embodiment of the present application. The vacuum cleaner  200  preferably includes a suction fan drive motor  220 , fan  206 , a large dirt centrifugal separator section  222  connected to the suction fan inlet  217  and a large collection chamber  214 , where all of these components are mounted in the floor housing  201 . See also  FIG. 17   
     A handle  205  is preferably pivotally attached to the housing  201 . A secondary cyclone separator section  260  is preferably mounted on the handle  205 , which is at least partially hollow to allow air to flow from housing  201  to the separator  264 . A second removable dirt collector  265  is provided with the secondary separator  264  which is for very fine dirt and need only be cleaned periodically. In addition, a HEPA filter  284  may also be provide to provide additional final filtering, if desired, as shown in  FIG. 22 . 
       FIG. 17  shows an internal perspective view of the housing  201  with a bottom cover removed such that the major components are visible. As illustrated, the primary cyclone separator section  222  is mounted adjacent to the suction fan motor and housing  220 . The fan  206  rotates to create suction and pull dirt and air from the pick up head area  209  through the tangential inlet  211  and into the cyclone chamber  219  of the separator  222 . The dirt rotates in the chamber  210  at high velocity and moves to the inner surface of the outer walls of the chamber and past the baffle  212  into the discharge area  227  from which it is discharged through tangential outlet  223  into the removable large dirt collector or bag  214  shown in  FIG. 16 . A belt  218  is preferably connected to a shaft of the motor or fan and is used to rotate brush  215  in the pick up head area  209  to help lift dirt off the floor. An exit duct  216  is positioned in the chamber  219  to allow the cleaned air to exit the chamber through the holes  225  formed in a wall therein. The duct  216  is connected to the fan inlet at  217 . Element  227  refers to the dirt swirl section, or collection section, of the chamber  219  which is downstream of the baffle  212  and includes the tangential dirt discharge outlet  223  for the dirt to be blown into the removable large dirt container  214 . Another advantage of discharging the dirt from the cyclone chamber is that the large dirt collection chamber or bag can take any desired shape to maximize dirt volume storage efficiency. 
     The suction fan  206  air is discharged into the hollow handle mounting  204  with some or most of it being provided to the collection duct  270  for connection to a jet assist slot  271  (See  FIG. 18 ) in the bottom cover  205 . Jet assisted suction is discussed above with reference to the vacuum cleaner  1  of  FIGS. 1-9 , for example. Generally, the high velocity air produces a low-pressure area just above the carpet or floor due to the Bernoulli effect. 
       FIG. 18  shows a bottom view of the vacuum cleaner  200  of  FIG. 17  with the bottom cover replaced. In addition, a recirculation air jet assist slot  271  around the suction pick-up opening  209  is shown with the rotating floor brush  215 . 
       FIG. 19  illustrates a cross sectional view of the housing  201  illustrating how a portion of the cleaned air from the chamber  10  can be redirected to the jet assist slot  271  of the head area  209  while other air is directed up the hollow handle portion  204  to the secondary separator  265 . 
       FIG. 20  is a schematic view of the centrifugal dirt separator section  222  and suction fan  206 . As illustrated, the exit air duct  216  of the chamber  210  is connected to the inlet of the fan  206 .  FIG. 20  also illustrates the relationship of the tangential inlet  211  of the chamber  210  and the tangential dirt outlet  223  as well as the openings  225  that are preferably formed to provide an inlet for the exit duct  216  to allow the cleaned air to escape chamber  222 . The suction fan  206  is shown attached to the centrifugal separator exit duct  216  so as to provide noise isolation from the intake of the vacuum cleaner  200  near the suction head area  209   
       FIG. 21  is an improvement on the features illustrated in  FIG. 20 . In this embodiment, a second insert  280  provided in the air exit duct  216  to provide Helmholtz dampening of sound. This absorbs the high velocity fan blade and high velocity air noise from coming back out the inlet  211 . 
       FIG. 22  illustrates the secondary cyclone separator  260  mounted on the handle  205  of the cleaner  200 . The separator  264  is optimized for separating very small particles from the cleaned air provided from the primary separator  222 . The separator chamber  264  thus includes a plurality of small diameter chambers  290  similar to the chambers  60  described above with reference to  FIGS. 8   a  and  8   b . The chambers include small tangential inlets and tapered walls but are arrange around the handle  204 . Slots are provided in the handle  205  to correspond to these inlet slots. The cup  265  is provided for dirt collection and is preferably removable. In one embodiment a disposable bag may be placed into the cup  265  to collect dirt. 
       FIG. 23  illustrates an alternative embodiment of a vacuum cleaner  300  where the primary cyclone separator  322  is mounted on hollow handle  308  and the larger dirt and much of the very small dirt is deposited into a non-porous bag or container  314 . The container  314  may be made larger in this embodiment since it is not part of the floor assembly. Secondary cyclone separation is provided in the separator  360 , which may also include a HEPA filter, if desired. The first and second separators  322 ,  360  however are similar to those described above with reference to vacuum  200 . 
       FIG. 24  shows the application of the disclosed cyclone separator illustrated in  FIGS. 6 and 12 , for example, in place of the cleanable filter  403  commonly used in central vacuum systems. Generally, in conventional systems such as system  400  dirt is sucked into a removable container  414  as shown in  FIG. 24 , so it can be discarded. However, the air is typically filtered by a cloth bag or other cleanable filter (see element  403 , for example) which is dusty to clean and reduces performance of the system as it gets clogged with dirt and dust. 
     In accordance with the present application, the central vacuum  410  has element  401  which represents a suction fan drive motor, and element  402  representing the suction fan while the cyclone separator is identified as element  413  which can be used to replace the filter  403  in the housing of a central vacuum cleaner  400 . The inlet port  406  from the central home vacuum is connected to the house vacuum piping which is connected to the tangential inlet of the separator  413 . A center air discharge duct similar to duct  16  of  FIG. 6  is preferably connected to the suction fan inlet  402  to allow the suction fan to draw air at high velocity through the tangential inlet of the cyclone centrifugal separator  413 . The separated dirt is discharged out tangential discharge  416  and drops into the container  414 . 
     Although the present invention has been described in relation to particular embodiments thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. It is preferred, therefore, that the present invention be limited not by the specific disclosure herein, but only by the appended claims.