Patent Publication Number: US-9844309-B2

Title: Vacuum

Description:
RELATED APPLICATIONS 
     The present application is a continuation of U.S. Continuation In Part application Ser. No. 14/310,763, filed on Jun. 20, 2014 and U.S. application Ser. No. 13/431,302 now Granted U.S. Pat. No. 9,271,620 on Mar. 1, 2016 entitled “VACUUM”, the contents of which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The present invention is directed toward a construction site or tool shop vacuum and, in particular, to a vacuum including a filter system and an airflow arrangement that periodically cleans the filter system during operation. 
     BACKGROUND OF THE INVENTION 
     Tool shop vacuum cleaners (e.g., wet-dry vacuums) are designed to collect debris from a work area or connected tool via suction. Such vacuums typically include a tank and motor that drives an impeller to generate an airstream within the tank. Since the airstream includes debris, care must be taken to prevent the debris from reaching the motor and causing damage. In light of this, conventional systems further include a filter positioned upstream from the motor to capture debris as the contaminated airflow passes through the tank. Over time, however, the debris accumulates on the filter, restricting airflow and hampering performance. For example, a filter initially enabling airflow of approximately 80 cfm may begin degrading within minutes of operation, diminishing airflow capacity to approximately 10 cfm. Consequently, conventional vacuum systems require regular cleaning or replacement of the filter. This process requires a user to stop vacuum operation, open the tank, and remove the filter for cleaning or replacement. This is a time-intensive process that interrupts workflow. 
     Thus, it would be desirable to provide an airflow arrangement configured to clean a filter during operation, thereby increasing filter life and extending time between manual cleaning of the filter, as well as filter replacement. 
     SUMMARY OF THE INVENTION 
     The present invention is directed toward a construction site shop vacuum including a tank and a lid coupled to the tank. A separator plate is disposed within the vacuum such that the lid generally defines a motor chamber and the tank generally defines a collection chamber. The motor chamber houses a motor assembly, which is supported by the separator plate. The collection chamber, oriented upstream from the motor assembly, houses a filter system suspended from the separator plate. The separator plate includes conduits that permit airflow between the collection and motor chambers. Airflow between the chambers is controlled utilizing a valve assembly that selectively opens and closes the conduits. 
     Specifically, the valve assembly operates in a first mode, in which contaminated airflow is drawn into the collection chamber, passing through the filter system in a first direction. The filter medium of the filter system captures debris present in the airflow, cleaning the air passing therethrough. The filtered airflow is then directed into the motor chamber, exiting the vacuum as exhaust. 
     The valve assembly further operates in a second mode, in which at least a portion of the filtered airflow is redirected from the motor chamber back into the collection chamber. Specifically, the airflow is directed through the filter system in a second direction to expel debris that has accumulated on the filter medium. With this configuration, the media of the filter system are periodically cleaned during operation of the vacuum. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a front perspective view of a vacuum in accordance with an embodiment of the invention. 
         FIG. 2  illustrates a rear perspective view of the vacuum device shown in  FIG. 1 . 
         FIG. 3  illustrates a wheel assembly structure for rollably supporting the vacuum on a floor surface. 
         FIG. 4  illustrates an arrangement of the wheel assembly of  FIG. 3  on the vacuum of  FIG. 1 . 
         FIG. 5  illustrates a hook tethered by a flexible strap to a connector secured to the vacuum of  FIG. 1 . 
         FIG. 6A  illustrates the hook and strap of  FIG. 5  securing a hose to the vacuum of  FIG. 1 . 
         FIG. 6B  illustrates the hook and strap of  FIG. 5  secured respectively to a lip of a tank and a head of the vacuum of  FIG. 1 . 
         FIG. 7A  illustrates a light source and pivotable support structure attached to the vacuum of  FIG. 1 . 
         FIG. 7B  illustrates an enlarged view of the light source and pivotable support structure of  FIG. 7A . 
         FIG. 8A  illustrates a cross sectional view of a sealing mechanism. 
         FIG. 8B  illustrates a bottom perspective view of the sealing mechanism of  FIG. 8A . 
         FIG. 9A  illustrates an isolated view of a separator plate in accordance with an embodiment of the invention. 
         FIG. 9B  illustrates a top perspective view of the separator plate shown in  FIG. 9A . 
         FIG. 9C  illustrates a bottom perspective view of the separator plate shown in  FIG. 9A . 
         FIG. 10A  illustrates a top perspective view of a valve assembly in accordance with an embodiment of the invention, the valve assembly being mounted on the separator plate of  FIG. 9A . 
         FIG. 10B  illustrates an isolated, front perspective view of the valve assembly shown in  FIG. 10A . 
         FIG. 10C  illustrates an isolated, rear perspective view of the valve assembly shown in  FIG. 10A . 
         FIG. 10D  illustrates a cross sectional view of a conduit and a valve of the valve assembly, showing the forces acting upon a disc. 
         FIG. 10E  illustrates a side perspective of an embodiment of a ski of the valve assembly of  FIG. 10A . 
         FIG. 10F  illustrates a side perspective view of another embodiment of a ski of the valve assembly of  FIG. 10A . 
         FIG. 11A  illustrates an isolated view of an airflow assembly in accordance with an embodiment of the invention. 
         FIGS. 11B and 11C  illustrate perspective views of the airflow assembly of  FIG. 11A  mounted on the separator plate shown in  FIG. 9A . 
         FIGS. 12A, 12B, and 12C  illustrate the vacuum system with the vacuum head and manifold removed, showing a motor shroud mounted on the separator plate of  FIG. 9A . 
         FIG. 13A  illustrates a front perspective view of a manifold in accordance with an embodiment of the invention, shown in isolation. 
         FIG. 13B  illustrates a cross sectional view of the manifold shown in  FIG. 13A . 
         FIG. 13C  illustrates a bottom perspective view of the manifold shown in  FIG. 13A . 
         FIG. 13D  illustrates a perspective cross-sectional view through manifold of  FIG. 13A . 
         FIG. 13E  illustrates a side cross-sectional view through the manifold of  FIG. 13A . 
         FIG. 13F  illustrates an enlarged side cross-sectional view of the manifold shown in  FIG. 13A . 
         FIG. 14A  illustrates an exploded view of the tank and the manifold of the vacuum system, showing the positional relationship between the manifold and the separator plate of  FIG. 9A . 
         FIGS. 14B and 14C  illustrate perspective views of vacuum system with the vacuum head removed for clarity, showing the manifold of  FIG. 13A  mounted on the separator plate of  FIG. 9A . 
         FIG. 15A  illustrates a perspective view of a filter assembly in accordance with an embodiment of the invention, shown mounted on the separator plate of  FIG. 9A . 
         FIG. 15B  illustrates a cross sectional view of the filter assembly shown in  FIG. 15A . 
         FIG. 16A  illustrates an exploded view of a filter device in accordance with an embodiment of the invention. 
         FIG. 16B  illustrates a perspective view of the filter device shown in  FIG. 16A . 
         FIGS. 17A-17C  illustrate schematic views showing the operation of the airflow assembly. 
         FIGS. 18A and 18B  illustrate a schematic views showing airflow through the filter device. 
         FIGS. 19A and 19B  illustrate a schematic views showing airflow through the airflow assembly. 
         FIG. 20  illustrates an electrical diagram in accordance with an embodiment of the invention. 
     
    
    
     Like reference numerals have been used to identify like elements throughout this disclosure. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIGS. 1 and 2 , a vacuum system  10  in accordance with an embodiment of the invention (e.g., a wet/dry vacuum cleaner) includes a body  100  having a tank portion  105  coupled to a head or head  110  via one or more latch devices  112 . Tank  105  may possess any dimensions and shapes suitable for its described purpose. 
     The tank portion  105  may further include one or more latch receptacles formed into the side wall  205 . Each latch receptacle receives a corresponding latch device operable to couple the tank  105  to the head  110 . 
     Referring to  FIGS. 3 and 4 , a vacuum supporting wheel assembly (e.g., rear wheels) may be in the form of a caster  305  including a wheel  315  disposed below a support structure  318 . The wheel  315  is rotatably mounted to a fork  320  that, in turn, is pivotally coupled to the support  318  via a central pin  322 . Support  318  includes an opening  316  for receiving pin  322  having an axis  319 . Wheel  315  may rotate about axis  319  in opening  316  or it may be held stationary as fork  320  is engaged by rotational stoppers  317 . Fork  320  extends from pin  322  such that a rotational axis of wheel  315  does not intersect with an axis of pin  312 . In this arrangement the axis of wheel  315  is offset from pin  322  as shown at the right in  FIG. 4  The wheel base is thereby shifted rearward providing for a larger wheel base with respect to the front wheels of the vacuum than a non-offset or centrally mounted wheelbases such as shown at the left in  FIG. 4 .  FIG. 4  illustrates how the offset pinned caster arrangement  306  provides a greater wheel base than the centrally arranged caster arrangement of  307 . 
     (e.g., rear wheels) Referring back to  FIG. 1 , the tank  105  further includes an intake port  255  formed into the side wall  205  (along the forward portion of the side wall). A vacuum connector  260 , secured to the exterior side of the intake port  255 , couples to a hose connector  265 , which, in turn, couples to a flexible tube (e.g., a hose) utilized to capture debris. 
     As illustrated in  FIGS. 5, 6A and 6B , a hook  530  is tethered to the vacuum via a flexible cord  532 . The cord is connected to an anchor  534  on an opposite end of the cord from the hook. The anchor is secured to the vacuum (e.g., on the head  110  of the vacuum). The hook may be pulled so that the cord extends around an object (e.g., the debris suction hose mentioned above) and then hooked to the vacuum. 
     A light  402  may be secured to a top of head  110 . The light may include a halogen lamp  404  or other type light.  FIGS. 7A and 7B  illustrate the light accessory. The light may pivot about an axis Ap and rotate about an axis Ax. A rotation structure  420  includes a first rotator  430  that is secured to the vacuum body  100  and a second rotator  440  that is fixed to and rotates with lamp  404 , but relative to first rotator  430 . A pivot structure  455  which is attached to second rotator  440  includes a first pivot  450  that pivots relative to a second pivot  460  about an axis Ap. Lamp  404  is attached to second pivot so that it can pivot up and down about axis Ap in a direction PD relative to body  100 . Lamp  404  can also swivel or rotate 360° about axis Ax in the SWD direction. The lamp can be powered by an independent extension cord to a wall outlet or power may be supplied by the vacuum directly or through an outlet socket on the vacuum (supplied by the vacuum main power cord). 
       FIGS. 8A and 8B  illustrate the interface and seal between head  110  and tank  105 . Two vertical walls  982 A and  982 B extend downward from the outer lower surface of separator plate  900 . At lower distal ends of the walls inwardly facing projections may extend. A channel or strip  983  of flexible sealing material (e.g., foam) may be inserted between the walls and within the projections to secure the material within the walls and projections. The channel  983  is shown deformed in  FIG. 8A  may be made of foam, rubber, flexible polymer or any suitable flexible material that may provide a good vacuum seal between head  110  and tank  105 . When assembled, channel  983  may extend below the walls  982 A and B. When head  110  is sealed to tank  105 , channel  983  is forced into contact with rim surface  984  of tank  105  thereby fluidly sealing the interface between tank  105  and head  110 . 
     Referring to  FIGS. 9A, 9B, and 9C , a separator plate  900  engages the tank rim  212 , separating the tank cavity  214  (the collection chamber) from the cavity of the vacuum head  110  (also called a motor chamber). The separator plate  900  includes a platform  905  (e.g., a generally circulate plate) and one or more leg members  907 A- 907 D. The platform  905  includes an upper (head facing) surface  910  and a lower (tank facing) surface  912 . The shaped and dimensions of the platform  905  may be any suitable for its described purpose. By way of example, the platform  905  may be substantially planar and possess a generally circular shape. A perimetral wall  915 , protruding upward from the platform upper surface  910 , extends about the circumference of the platform  905 . As noted above, the upper surface  910  of the platform  905  may further include one or more connection posts  917  that engage (e.g., mate, receive, etc.) corresponding connection posts  707  extending from the vacuum head  110 . Fasteners may extend through the connection posts  707 ,  917  to secure the lid  110  to the separator plate  900 . A pair of diametrically opposed lips  920 A,  920 B extends axially (upward) from the perimetral wall  915  to provide an engagement member for each of the latch devices  112 , as described above. The platform  905  may further include one or more reinforcing ribs  921  spanning the platform upper surface  910  to enhance the strength of the platform. 
     The leg members  907 A- 907 D, extending distally from the platform lower surface  912 , are configured to elevate the platform  905  and, in particular, to suspend the filter system above a supporting surface when the separator is placed directly upon the supporting surface. That is the length of the legs is selected to prevent the filters from contacting the ground when the separator plate  900  and/or head  110  is removed from the tank and set on a surface (seen in  FIGS. 7E and 15A ). The leg members  907 A- 907 D are located proximate the outer edge of the separator plate, being disposed a predetermined angular positions thereon. 
     The leg members  907 A- 907 D, moreover, are configured to key the separator plate  900  to the tank  105  such that the separator plate is oriented in a specific rotational position when inserted into the tank  105 . As shown in the figures, the platform  905  includes a first forward leg  907 A, a second forward leg  907 B, a first rearward leg  907 C, and a second rearward leg  907 D. Each leg  907 A- 907 D includes a proximal leg portion  922  and a distal leg portion  925 . The proximal leg portion  922  of the forward legs  907 A,  907 B includes a notch  927  (e.g., a tapered (V-shaped) notch) configured to receive the guide element  675 A,  675 B protruding from the interior surface  670  of the tank  105 . As explained above, the guide element  675 A,  675 B is positioned at predetermined positions along the tank. The notch  927  aligns with each of the tank guide elements  675 A.  675 B such that the first guide element  675 A is received within the notch of the first forward leg  907 A and the second guide element  675 B is received within the notch of the second forward leg  907 B. Consequently, in order for the separator plate  900  to be inserted into the tank cavity, the notch  927 A of first leg member  907 A must be aligned with the first guide element  675 A and the notch  927 B of the second leg member  907 B must be aligned with the second guide element  675 B. Should the forward (notched) leg members  907 A,  907 B not be aligned with their corresponding guide elements  675 A,  675 B (i.e., should the rotational position of the separator plate  900  differ from the normal/predetermined position such that no leg or an unnotched leg is aligned with the guide elements), insertion of the separator plate  900  into the tank cavity  214  will be prohibited. 
     The separator plate  900  further includes a conduit system to enable the flow of air between the tank  105  (the collection chamber  214 ) and the head  110  (the motor chamber). In the embodiment illustrated, the platform  905  of the separator plate  900  includes a central, raised platform or deck  902  with a first conduit pair  935  and a second conduit pair  940 . The first conduit pair  935  includes a first (forward) suction conduit or port  935 A and a first (rearward) cleaning conduit or port  935 B. Similarly, the second conduit pair  940  includes a second (forward) suction conduit or port  940 A and a second (rearward) cleaning conduit or port  940 B. The conduits  935 A,  935 B of the first conduit pair  935  are positioned such that the conduits are disposed over the first filter  1505 A ( FIG. 15 ) of the filter system, while the conduits  940 A,  940 B of the second conduit pair  940  are positioned such that they are disposed over the second filter  1505 B of the filter system (i.e., each filter is in fluid communication with a conduit pair). 
     The conduits  935 A,  935 B,  940 A,  940 B may possess any shape and dimensions suitable for their described purpose. By way of example, each conduit  935 A,  935 B,  940 A,  940 B may be generally cylindrical. Each conduit, moreover, may include a conduit baffle operable to direct the airflow in a predetermined direction. As seen best in  FIG. 9A , the suction conduit  935 A,  940 A may include an inboard conduit baffle  942 A that curves radially inward with respect to the platform  905  to direct the air inboard, while the cleaning conduits  935 B,  940 B may include an outboard conduit baffle  942 B that curves radially outward to direct air outboard (toward the perimeter of the platform). 
     The upper surface  910  of the platform  905  further includes first  945 A, second  945 B, and third  945 C support walls that cooperate to support the airflow assembly. As shown, the first support wall  945 A extends upward from the upper surface  910  of the platform  905 , being oriented between the suction  935 A,  940 A and the cleaning  935 B,  940 B conduits. The second support wall  945 B is disposed proximate the cleaning conduits  940 A,  940 B (i.e., is disposed outboard with respect to the first support wall). The third support wall  945 C, moreover, is positioned outboard from the second support wall  945 B. Each support walls  945 A- 945 C is spaced from its adjacent support wall to define a cavity therebetween. Specifically, the first  945 A and second  945 B support walls define a fan cavity  950  that receives the fan of the airflow assembly. Similarly, the second  945 B and third  945 C support walls cooperate to define a motor cavity  955  that receives the motor of the airflow assembly. Each support wall  945 A,  945 B,  945 C includes a cut-out section  947  that receives and supports various components of the airflow assembly. By way of example, the second and third support walls cooperate to support the motor of the airflow assembly, with the motor resting within the cut-out section. The motor cavity  955  further includes areas  957  for supporting valve solenoid switches (discussed in greater detail below). 
     The separator plate  900  further includes a pair of opposed motor intake walls  958  extending from the third support wall  945 C to the perimetral wall  915 . The motor intake walls  958  cooperate with a motor shroud  1205  ( FIG. 12A ) to define a motor air intake area  960  that aligns with second head vent  715 B. Similarly, opposed walls  962  cooperate with the motor shroud  1205  to define a motor exhaust area  965  that aligns with third head vent  715 C. 
     A deflection wall or baffle  970  extends upward from platform upper surface  910  (e.g., the height of the wall may be substantially equal to or greater than the height of the deck  902 ). The platform baffle  970  is positioned between the deck  902  and the perimetral wall  915 . The platform baffle  970  gradually curves such that it extends from a position along a lateral side of the deck  902  to a position along the forward side of the deck. The platform baffle  970  is operable to direct cooling air exhausted by the manifold  1305  ( FIG. 13A ) toward electronics housed within the head  110 , thereby cooling the electronics (discussed in greater detail below). 
     The platform  905  further includes a first yoke  975 A located proximate the first cleaning conduit  935 B and a second yoke  975 B located proximate the second cleaning conduit  940 B. Each yoke  975 A,  975 B supports an associated butterfly valve  1005 A,  1005 B ( FIG. 10A ) of the valve assembly to enable rotation of the valve on the yoke (discussed in greater detail below). 
     A series of downward-extending, angled fins  985  may be angularly spaced about the platform  905 , being located near the outer edge of the platform, proximate the shoulder  980 . The fins  985  serve as guides during the insertion of the separator plate  900  into the tank cavity  214 . A bracket  990  is also disposed on the platform lower surface  912  that receives the conductive member  635  of the electrostatic discharge device. As shown, the conductive member  635  is coupled to the platform  905  via the conductive fastener  655 . 
     A valve assembly, disposed on platform upper surface  910 , opens and closes one or more of the separator conduits  935 A,  935 B,  940 A,  940 B to selectively permit fluid (air) therethrough. In the embodiment illustrated in  FIGS. 10A-10C , the valve assembly  1000  includes a first solenoid  1002 A in communication with to a first butterfly valve  1005 A and a second solenoid  1002 B in communication with to a second butterfly valve  1005 B. The first butterfly valve  1005 A is supported by the first platform yoke  975 A, while the second butterfly valve is supported by the second platform yoke  975 B. As seen in  FIG. 10A , the valve assembly  1000  is positioned on the separator plate  900 , with each solenoid  1002 A,  1002 B being positioned within areas  957  as described above. The solenoids  1002 A,  1002 B may be secured to the platform  905  by a cover or bridge  1040  coupled thereto. 
     The first butterfly valve  1005 A selectively permits airflow through the first conduit pair  935 A,  935 B. Similarly, the second butterfly valve  1005 B selectively permits airflow through the second conduit pair  940 A,  940 B. Each butterfly valve  1005 A,  1005 B includes an elongated shaft  1010 A,  1010 B supporting a first or distal disc  1015 A and a second or proximal disc  1015 B longitudinally spaced along the shaft and rotationally offset from the distal disc by, e.g., approximately 45°. 
     The proximal end of the shaft  1010 A,  1010 B is connected to a crank arm  1017 A,  1017 B, which, in turn, is pivotally coupled to a linking member  1020 A,  1020 B via a pivot pin  1022 A,  1022 B. The linking member  1020 A,  1020 B is repositioned via a plunger  1025 A,  1025 B that is driven by the solenoid  1002 A,  1002 B. Specifically, the plunger  1025 A,  1025 B reciprocates axially to rotate the discs. The linking member  1020 A,  1020 B may further include a downward-extending, curved support or ski  1030 A,  1030 B configured to slide along the platform upper surface  910  as the plunger  1025 A,  1025 B reciprocates. The ski  1030 A,  1030 B maintains the positioning of the plunger  1025 A,  1025 B with respect to the solenoid during the plunger&#39;s reciprocal motion, keeping the plunger aligned with the drum of the solenoid  1002 A,  1002 B and preventing the plunger from becoming jammed in the solenoid drum at full extension. With this configuration, each solenoid  1002 A,  1002 B may be selectively engaged to rotate the shaft  1010 A,  1010 B about its longitudinal axis in a clockwise or counter clockwise direction. The degree of rotation includes, but is not limited to, approximately 45°.  FIGS. 10E and 10F  respectively show alternate embodiment skis  1020 C and  1020 D. Ski  1020 D also includes an opening location member  1022 D disposed in proximity to the opening in which plunger  1025 A would be pinned. Opening location member  1022 D aids in positioning the plunger for pinning to ski  1020 D and for maintaining ski  1020 D orientation with respect to plunger  1025 A. 
     As a result, the valve assembly  1000  may selectively position each disc  1015 A,  1015 B with respect to its associated conduit  935 A,  935 B,  940 A,  940 B to enable the passage of fluid (e.g., air) therethrough. In operation, the valve assembly  1000  rotationally positions the discs  1015 A,  1015 B in a first position, in which the suction conduits  935 A,  940 A are opened and the cleaning conduits  935 B,  940 B are closed. That is, the butterfly valve  1005 A,  1005 B positions the shaft  1010 A,  1010 B such that the first disc  1015 A is oriented generally transverse to the opening defined by the suction conduit  935 A,  940 A (as illustrated in  FIG. 10A ), thereby permitting airflow between the tank  105  (the collection chamber  214 ) and the head  110  (the motor chamber). The second disc  1015 B, meanwhile, is positioned such that the disc completely covers the opening of the cleaning conduit  935 B,  940 B preventing the flow of air between the head  110  to the tank  105 . Alternatively, the valves  1005 A,  1005 B may rotationally position the discs  1015 A,  1015 B in a second (reversed) position, in which the suction conduits  935 A,  940 A are closed and the cleaning conduits  935 B,  940 B are opened. 
     As shown in  FIG. 10D , the conduits  935 A,  935 B,  940 A,  940 B and discs  1015 A,  1015 B are configured such that air flowing through the conduit creates a balanced system in which the forces on the butterfly valve  1005 A,  1005 B are equally applied across both surfaces of the disc  1015 A,  1015 B (indicated by arrows F 1  and F 2 ). Specifically, when an air pressure (positive or negative) is experienced on the upper side of the disk, the downward force (F 1  upper) on one side of the rotating axis is generally equal to the downward force (F 2  upper) on the other side of the axis. Therefore, a pressure on the top side of the disk does not significantly increase the force necessary to toggle the valve. Likewise, when an air pressure is experienced on the lower side of the disk, the upward force (F 1  lower) on one side of the rotating axis is generally equal to the upward force (F 2  lower) on the other side of the axis. Therefore, a pressure on the lower side of the disk does not significantly increase the force necessary to toggle the valve to its next operating condition. This enables the utilization of a small solenoid to rotate the valve  1005 A,  1005 B as described above, and provides an advantage over other valve types (e.g., piston valves, etc.) which have larger pressures to overcome and require large forces to toggle between operating positions. That is, the conduit structure enables the use of a lower power solenoid since valve rotation does not require overcoming a significant eccentric force applied to the disc  1015 A,  1015 B by the air in or airflow through the conduit. 
     An airflow assembly, housed within the motor chamber defined by head  110  and supported on the upper platform surface  910 , generates air pressure (positive and/or negative), within the vacuum device  10 , as well directs the flow of air within the head  110 . Referring to  FIGS. 11A-11C , the airflow assembly includes an airflow generating device  1102  having a centrifugal fan  1105  driven by a motor  1107 . The fan  1105  includes an annular housing or baffle  1110  and a plurality of slots  1112  disposed about the perimeter of the housing. The slots  1112  may be angled (e.g., offset and/or nonparallel to the rotational axis of the housing) to direct air in a predetermined direction. With this configuration, air is drawn into the central channel  1115  and is directed radially outward (from the fan rotational axis) through the slots  1112 . The airflow generating device  1102  may further include a forward gasket  1122  coupled to the forward (inboard facing) side of the fan  1105 , and a manifold spacer  1125  coupled to the rearward side of the fan. The motor  1107  may include any type of motor suitable for its described purpose. By way of example, the motor  1107  may include a universal series motor with a central channel  1127 . The motor  1107  is configured to drive (e.g., rotate) the fan  1105  in a clockwise and/or counterclockwise direction, as well as to draw cooling air into the motor channel  1127 . In an embodiment, the motor  1107  rotates the fan  1105  in a predetermined direction to generate a negative pressure within the vacuum device  10 , which, in turn, generates a suction airstream (an intake airstream) that enters the tank portion  105  via the inlet port  255 . As illustrated, the forward side of the motor  1107  may be coupled to the rearward (outboard facing) side of the fan  1105 , and a rearward gasket  1130  may be coupled to the outboard side of the motor. 
     Referring to  FIGS. 11B and 11C , the airflow generating device  1102  is oriented on the separator plate platform  905  such that it is located between the butterfly valves  1005 A,  1005 B, with the fan  1105  and manifold spacer  1125  being positioned within the fan cavity  950  of the platform  905 , as well as aligned with the cut out section  947  formed into the first  945 A and second  945 B walls. The motor  1107 , moreover, is position within motor cavity  955  such that the motor channel  1127  is aligned with the cut-out sections formed into the second  945 B and third  945 C platform walls. In a preferred embodiment, the fan  1105  is oriented such that its rotational axis R is oriented generally horizontally, i.e., such that the rotational axis is generally parallel to the platform  905  of the separator plate  900 . Stated another way, the fan rotational axis R is oriented generally transverse (e.g. orthogonal) to the longitudinal axis of a filter  1505 A,  1505 B ( FIG. 15 ). As such, the air intake direction of the fan  1105  may be oriented generally transverse (e.g., generally orthogonal) to the airflow passing through the conduit pairs  935 ,  940 . 
     Referring to  FIGS. 12A and 12B , the motor  1107  is housed in a motor shroud  1205  defining a motor air intake port  1210  and a motor air outlet or exhaust port  1220 . The motor shroud  1205  separates the cooling airstream generated by the motor from the vacuum airstream. The intake port  1210  cooperates with walls  958  on the platform  905  to define the motor intake area  960  as described above. Similarly, the exhaust port  1220  cooperates with the walls  962  on the platform upper surface  910  to define the motor exhaust area  965  as described above. In operation, the ambient air is drawn into the motor air intake  1210 , travels over the motor (cooling it), and is then exhausted via motor air exhaust  1220 . 
       FIG. 12C  shows a top perspective view of separation plate  900  including a baffle  970 D for directing air from discharge of the fan  1105  to electronics  720 D for cooling of the electronics.  FIG. 12C  illustrates cooling air flow arrows CAF 2  showing the path which air takes on its way to dashboard  720 D. 
     The airflow assembly further includes a manifold operable to direct the airflow in predetermined directions. The manifold includes a plurality of chambers that function as baffles, cooperating to direct airflow in predetermined directions. Referring to  FIGS. 13A-13C , the manifold  1305  includes a forward inlet chamber  1310 , an intermediate fan discharge chamber  1315 , and a rearward exhaust chamber  1320 . The exhaust chamber  1320  includes an exhaust port  1325  to permit exhaust of the filtered air from the manifold  1305 . In addition, the fan discharge chamber  1315  includes a first window or opening  1330  configured to permit the flow of fluid between the fan discharge chamber  1315  and the exhaust chamber  1320 . Additionally, the fan discharge chamber  1315  includes a second window or opening  1335  including an interior deflector  1337  extending angularly inward into the fan discharge chamber such that it directs a portion of the air flowing downstream, through the manifold out of the manifold and into the cavity defined by the head  110 . 
     In another embodiment, manifold  1305  includes a forward inlet chamber  1310 D. Adjacent to forward inlet chamber  1310 D is a fan discharge chamber  1315 D. A blower baffle  1316 D is disposed in fan discharge chamber  1315 D. A portion of fan discharge air  1306 D is directed toward motor  1107  by blower baffle  1316 D and passes over motor  1107 . At times during vacuum operation, discharge air  1306 D is at a lower temperature than motor  1107  and serves to cool motor  1107  as it passes over motor  1107 . 
     In an alternate embodiment, like with the prior described vacuum, the vacuum includes a forward inlet chamber  1310  for defining an airflow passage between suction ports  935 A,  940 A and the fan intake. In the alternate embodiment however, air passing through the fan discharge chamber  1315 D can be redirected to flow over the exterior of motor  1107  before it is discharged into the vacuum head  110 . At times during vacuum operation, discharge air  1306 D is at a lower temperature than motor  1107  and serves to cool motor  1107  as it passes over motor  1107 . Air discharged from discharge chamber  1315  may also be diverted toward vacuum electronics to cool such electronics. After contacting and cooling the motor, the electronics, and any other components it contacts, the air is discharged from the vacuum through openings in vacuum head  110 . 
       FIGS. 13D-F  show blower baffle  1316 D disposed in fan discharge chamber  1315 D. Baffle  1316 D serves as an air diversion baffle or structure for directing at least a portion of the discharge air from the fan discharge  1105  toward and onto motor  1107 .  FIG. 13F  illustrates cooling air flow arrows CAF 1  showing the path which motor  1107  cooling air takes between the fan discharge and motor  1107 . 
     Referring to  FIGS. 14A-14C , once coupled to the separation plate  900 , the inlet chamber  1310  is positioned over the suction conduits  935 A,  940 A, the discharge chamber  1315  is positioned over the fan  1105  and the cleaning conduits  935 B,  940 B, and the exhaust chamber  1320  is positioned over the motor shroud  1205 . The operation of the manifold  1305  is discussed in greater detail below. 
     The vacuum device  10  includes a filter assembly that captures particles within the contaminated airstream entering the tank  105 , cleaning the airstream as the airstream flows through the body  100  of the vacuum device  10 . In the embodiment illustrated in  FIGS. 15A and 15B , the filter assembly  1500  includes a first filter  1505 A and a second filter  1505 B. The filters  1505 A,  1505 B may be coupled to the platform lower surface  912 , being generally radially aligned along opposite sides of plate center point and suspended above the floor of the tank  105 . Additionally, as best seen in  FIG. 15B , each filter  1505 A,  1505 B is in communication with both conduits  935 A,  935 B,  940 A,  940 B forming a conduit pair  935 ,  940  (i.e., the first filter  1505 A is in fluid communication with the first conduit pair  935 , while second filter  1505 B is in fluid communication with second conduit pair  940 ). 
     Referring to embodiment illustrated in  FIGS. 16A and 16B , each filter  1505 A,  1505 B may include a substantially rigid, inner cage  1605  generally concentrically disposed within a core member or outer cage  1610 . The inner cage  1605 , which houses a ball float  1612 , may be generally cylindrical. The outer cage  1610 , which formed of wire screen, may possess a generally frustoconical shape. The outer cage is generally rigid, providing stiffness from end to end such that it can be threadingly tightened along one of the ends to an end cap. Specifically, the lower (narrower) terminus of the outer cage  1610  couples to a lower end cap  1615 , while the upper (wider) terminus of the outer cage couples to an upper end cap  1620 . The lower end cap  1615  may be in form of a solid, circular plate with an exterior wall extending upward from the plate and extending about its periphery, as well as an inner wall or rib  1622  concentric with the outer wall and configured to engage the core member  1610  lower end. The upper end cap  1620  may be generally annular, including a plurality of ratchet teeth  1625  disposed along on its upper side (being angularly spaced about the perimeter of the cap). The inner channel  1630  of the upper end cap  1620 , moreover, is threaded to mate with corresponding threads on a filter mount  1635  (discussed in greater detail below). 
     A filter medium  1640  operable to remove particulates from the airstream is mounted on the outer cage  1610 . As shown, the filter medium  1640  may in the form of a sleeve including a hollow channel  1642  defined by the interior surface of a wall  1643  and a plurality of longitudinal fins  1644  angularly spaced about the exterior surface of the wall. The filter medium  1640  may possess a shape and dimensions that enable it to contour to the exterior surface of the outer cage  1610  (e.g., the filter may be generally frustoconical). By way of specific example, the filter medium  1640  may possess an upper (wide end) diameter of approximately 6.4 inches, a lower (narrow end diameter) of approximately 5.25 inches, and a length (height) of approximately 5.2 inches. It should be understood that the filter medium  1640  may possess any suitable shape and dimensions, and may be formed of any material an have any structure suitable for its described purpose. 
     The filter mount  1635 , secured to the lower surface  912  of the separator plate  900  (e.g., via fasteners), couples to the upper end cap  1620 . The filter mount  1635  includes a seat member  1655  (e.g., a ball seat), a base  1660 , and a threaded plug  1665  that engages the threads of the inner channel  1630  of the upper end cap  1620 . A channel  1670  is formed into the filter mount  1635  to permit airflow from the filter to its associated conduit pair  935 ,  940 . 
     The operation of the vacuum device  10  is explained with references to  FIGS. 17A-17C  and  FIGS. 18A-18C . The motor  1107  is activated (e.g., via controls  725  on dashboard  720 ), rotating the fan  1105 . The fan  1105  creates a vacuum (suction) airflow within the body  100  of the vacuum device  10 . Referring to  FIGS. 17A and 18A , in a first operational mode, the butterfly values  1005 A,  1005 B are positioned in their normal, full suction position. In this position, the vacuum device  10  generates suction airflow that is filtered through the filter medium  1640  of each filter  1505 A,  1505 B. Specifically, the butterfly valves  1005 A,  1005 B are set such that both the first suction conduit  935 A and the second suction conduit  940 A are opened, and both the first cleaning conduit  935 B and the second cleaning conduit  940 B are closed. As a result, the fan  1105  draws contaminated air A 1  including debris (particulate material) into the tank  105  (e.g., via an inlet/hose). The contaminated air A 1  travels through the collection chamber  214  and is drawn toward the filters  1505 A,  1505 B. Specifically, the air passes through the filter medium  1640  in a first filter direction, with the air entering the filter medium via the medium exterior surface. As the contaminated air A 1  passes through the filter medium  1640  of the filters  1505 A,  1505 B, particles and other debris within the contaminated air are captured by the filter medium. Larger debris falls (via gravity) to the bottom of the tank  105 , while smaller debris becomes attached and/or embedded within the filter medium  1640 . This airstream, now filtered air A 2 , passes upward, through the central channel of the filter (as defined by inner cage  1605 ) and toward the suction conduit  935 A,  940 A. 
     The filtered air A 2  passes through the suction conduit  935 A,  940 A, i.e., from the collection chamber defined by the tank  105  and into the motor chamber defined by the vacuum head  110 . Specifically, the filtered air A 2  enters the manifold  1305  of the air assembly disposed within the motor chamber, entering the inlet chamber  1310 . The filtered air A 2  is drawn into the fan central aperture  1115  and is directed radially outward therefrom as fan exhaust or discharge air A 3  (indicated by arrows). The discharge air A 3  is directed, via the slots  1112 , into the manifold discharge chamber  1315 . The cleaner conduits  935 B,  940 B are closed/sealed; consequently, a portion of the discharge air A 3  is directed from the discharge chamber  1315 , through the first window  1330 , and into the exhaust chamber  1320 . Additionally, a portion of the discharge air A 3  is deflected by manifold deflector  1337  such that it passes through the second window  1335 . As such, a portion of the discharge air A 3  exits the manifold  1305  (and the vacuum system  10 ) as manifold exhaust air A 4  via manifold exhaust outlet  1325 . Additionally, a portion of the discharge air is recycled as electronics coolant A 3 ′, exiting the manifold  1305  and returning to the motor chamber defined by the head  110  to cool electronics housed in the head (discussed in greater detail below). 
     Referring to  FIGS. 17B and 18B , in a second operational mode, the filter medium  1640  of the first filter  1505 A is purged of debris. In this mode, the first butterfly valve  1005 A is engaged to reorient the valve from its normal position to its purge position. Specifically, the first rod  1010 A is rotated such that distal disc  1015 A covers/seals the first suction conduit  935 A and the proximal disc  1015 B is positioned such that it is oriented generally transverse to the opening of the first cleaning conduit  935 B. In this configuration, the first cleaning conduit  935 B is opened, while the first suction conduit  935 A is closed/sealed. The second butterfly valve  1005 B remains in its normal position as described above, with the second suction conduit  940 A being opened and the second cleaning conduit  940 B being closed/sealed. 
     In this configuration, the suction airflow through the first filter  1505 A ceases. That is, contaminated air A 1  no longer passes through the filter medium  1640  of the first filter  1505 A via the filter medium exterior surface. Suction airflow through the second filter  1505 B, however, is maintained. The filtered air A 2  from the second filter  1505 B enters the manifold  1305 , where it is drawn into the fan  1105  and expelled through fan slots  1112  as discharge air A 3 . With the cleaning conduit  935 B in its opened position, at least a portion of the discharge air A 3  is directed downward, into the first cleaning conduit  935 B (indicated by arrow). The discharge air A 3  enters the central channel of the first filter  1505 A (as defined by the inner cage  1605 ) and is forced radially outward, passing through the filter medium  1640  in a second filter direction. As shown in  FIG. 18B , this outward airflow functions as a purging airflow effective to dislodge at least a portion of the debris and/or particles  1800  previously attached to and/or embedded within the filter medium  1640 . Any remaining discharge air A 3  (i.e., and discharge air not directed into the cleaning conduit  935 B) is directed as indicated above, being expelled from the tank as either manifold exhaust A 4  or being recycled as electronics coolant A 3 ′. 
     In a third operational mode, the filter medium  1640  of the second filter  1505 B is purged. The same operation described above with regard to the first filter  1505 A occurs with the second filter  1505 B. Referring to  FIGS. 17C and 18B , the first butterfly valve  1005 A is returned to its normal position, in which the first suction conduit  935 A is opened and first cleaning conduit  935 B is sealed/closed. In addition, the second butterfly valve  1005 B is engaged, moving the valve from its normal position to a purge position, in which the second suction conduit  940 A is closed and the second cleaning conduit  940 B is opened. Similar to that described above, discharge airflow A 3  drawn into the manifold  1305  as filtered air is either directed into the second cleaning conduit  940 B, out of the head  1010  via the manifold exhaust chamber  1320 , or back into the head  1010  via second window  1035 . The discharge air A 3  that is directed through the cleaning conduit passes through the filter medium  1640  of the second filter  1505 B in a second direction (opposite the first direction), thereby purging the filter medium of debris captured thereon. 
     The amount of time for the purge is not particularly limited. By way of example, the airflow system may operate in the suction mode for a first predetermined period of time and in the purging/cleaning mode for a second predetermined period of time, with the second period of time being less than the first period. In an embodiment, the valve system cycles, generating suction air for approximately 30 seconds, and then generating purge air for approximately 0.3 seconds, alternately purging the first filter  1505 A and the second filter  705 B. This process continues, with the filters  1505 A,  1505 B alternately being purged in approximately every 20 seconds. 
     Referring to  FIGS. 19A and 19B , during operation, cooling air A 5  for the motor  1007  is drawn in through the motor intake port  1210  of the motor shroud  1205 , where it is directed across the motor, cooling it, and then out through motor exhaust  1220  as motor exhaust air A 5 ′. As mentioned above, the motor airflow A 5 , A 5 ′ remains separate from the vacuum airflow A 1 , A 2 , A 3 , A 3 ′, A 4  vacuum filtered air, with the motor shroud preventing the motor air A 5 , A 5 ′ from entering the manifold  1305 . 
       FIG. 20  illustrates an electrical schematic for the vacuum device  10  in accordance with an embodiment of the invention. As shown, the electrical system  2000  includes a microprocessor  2005  in communication with the motor via motor connect  2010 , as well as the butterfly valves  1005 ,  1005 B via a solenoid connect  2015 , which, in turn, is in communication with solenoid switches  1002 A,  1002 B. The system  2000  may further include a pressure or flow sensor  2020  operable to indicate when the intake airflow A 1  is reaches (e.g., is above or below) a predetermined threshold value. By way of example, it may indicate when the airflow pressure or flow velocity is below a specified value, thereby notifying the user that the filters must be removed for manual cleaning or replacement. 
     While the present invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. It is to be understood that terms such as “top”, “bottom”, “front”, “rear”, “side”, “height”, “length”, “width”, “upper”, “lower”, “interior”, “exterior”, and the like as may be used herein, merely describe points of reference and do not limit the present invention to any particular orientation or configuration.