Abstract:
An impeller for use in a two-chamber extracting blower that separates liquid and solid contaminants from a supply of and provides a supply of clean air moving at high velocity air. The impeller includes a plurality of blades wherein each blade includes a first section perpendicular to and formed of the blade and a second section perpendicular to the first section, also formed of the blade and radiating outward. The height of each section and the construction of the main section of the blade create differing pressure zones during rotation of the impeller, segregating air contain the impurities and prompting separation of the impurities. The construction of the first and second sections promotes more efficient and quieter operation, strengthens the blade, and permits removal of the impeller.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     None. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not Applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention pertains to two-chamber extracting blowers that separate liquid and solid contaminants from a supply of and provide a supply of clean air moving at high velocity air. 
     2. Description of the Related Art 
     Blowers for providing air flow are well known. Also well known is the obstacle of heavier-than-air contaminants in the air intake and the desire to remove those contaminants before outflow, particularly as such contaminants can be damaging to downstream equipment. The prior art includes two-chamber extracting blowers that separate contaminants from an intake supply and provide a supply of clean air moving at high velocity. These blowers typically function by rotating an impeller within a divided housing, which draw air axially into the housing and across the blades of the impeller and use the centrifugal effect of the blades to separate the air from the heavier contaminants. In operation, the construction of the blades of the impeller create an area of low pressure that draws air into the blower. Once drawn into the blower, the rotation of the blades causes the air to be forced radially outward between the blades. The air having little or no contamination is quickly forced to the edge of the blades before that air can pass axially into the second chamber within the housing. Air carrying contaminants and having momentum from being drawn into the blower continues axially moving into the second chamber and is redirected by the rotation of the blades in that second chamber, causing the air and contaminants to be directed to the exterior of the second chamber, wherein the contaminants are expelled. This construction has shortcomings, including blade maintenance, noise generation, and effectiveness. 
     Prior attempts to overcome these shortcomings have included notching the outer edge of the impeller blades to extend about the housing divider or partition separating the first and second chambers (the clean and dirty air chambers). While reducing the contaminant-free air lost to the second chamber, this construction can impede the motion of contaminant-bearing air to the second chamber and precludes removal of the impeller without simultaneous removal of the partition. Impeller removal can be of significant importance when trying to maintain clean blades so as to promote direction of contaminant-free air. 
     Other prior art attempts have utilized a wiper welded to each blade to guide contaminants to the second chamber. However, because contaminant-bearing air necessarily is flowing over and impacting the weld, the weld surface can become pitted and subject to abrasion. Moreover, as the weld is contacted by corrosive contaminants, the weld is further weakened, causing the cracks inherent in a weld to propagate. 
     Other prior art attempts have attempted to use wiper-free blades in an impeller notch about the chamber partition in conjunction with an third chamber formed on the outer edge of the first chamber to skim the air of the first chamber for lighter contaminants and heavier contaminants which did not pass to the second chamber are separated from the volume of “clean” air exiting the blower and to cause the contaminants in the air to be ejected with the contaminant-bearing air. This construction, however, requires the addition of components to the housing. 
     Other prior attempts have attempted to affix a wiper to each blade of an impeller notch about the chamber partition and to construct the blades of the impeller to provide differing cross-sectional areas for the portions of each blade in the first and second chambers to provide pressure differentials between the two chambers. Thus, in addition to shortcomings of a wiper-based impeller, the impeller cannot be easily removed. 
     Thus, there is a need in the art for an impeller for use in an two-chamber contaminant-extracting blower which operates efficiently and more quietly, permits ease of access and removal of the impeller, avoids welds and additional parts, and generates a pressure differential between the two chambers. 
     SUMMARY OF THE INVENTION 
     The present invention therefore meets the above needs and overcomes one or more deficiencies in the prior art by providing an impeller with blades with cross sections areas sized to the two chambers, increases the efficiency of removal of contaminants, avoids the notching about the partition between the chambers, and features sections of the blade bent to provide increased strength 
     Unlike prior inventions, the invention avoids the notch fixing the impeller within the blower housing, avoids the use of crack-inducing welds in favor of material bending, and utilizes differing sizes for the first and second sections of the blade outer edge to promotion air flow and contaminant separation. 
     In particular, the invention, which may be a blower or the impeller for use in a two-chamber contaminant-extracting blower, where the impeller includes a rear circular plate with a mounting hub and a plurality of outwardly-radiating blades affixed thereto sized to fit within the housing of the blower, and each blade includes a second-chamber section extending from the mounting hub and having a large cross-sectional area, a first-chamber section extending upward from the outer portion of the second-chamber section, a first blade extension formed by perpendicularly bending the portion of the blade extending beyond the second-chamber section and which extends from the first-chamber section of the blade into the second-chamber section of the blade, and a second blade extension formed by perpendicularly bending a portion of the first blade extension to be parallel to and outwardly extending from the blade and which extends from the first-section of the toward the end of the first blade extension. 
     Additional aspects, advantages, and embodiments of the invention will become apparent to those skilled in the art from the following description of the various embodiments and related drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the described features, advantages, and objects of the invention, as well as others which will become apparent are attained and can be understood in detail; more particular description of the invention briefly summarized above may be had by referring to the embodiments thereof that are illustrated in the drawings, which drawings form a part of this specification. It is to be noted, however, that the appended drawings illustrate only typical preferred embodiments of the invention and are therefore not to be considered limiting of its scope as the invention may admit to other equally effective embodiments. 
       In the drawings: 
         FIG. 1  is an illustration of a view one embodiment of the present invention of the impeller positioned relative to the housing. 
         FIG. 2  is an illustration of a bottom view of one embodiment of the present invention of the impeller positioned relative to the housing and the intake cover. 
         FIG. 3  is an illustration of a side view of one embodiment of the present invention of the impeller positioned relative to the housing and the intake cover. 
         FIG. 4  is an illustration of a rear view of one embodiment of the present invention of the impeller positioned relative to the housing and the intake cover. 
         FIG. 5  is an illustration of a side view of one embodiment of the present invention of the impeller positioned within the housing and the housing side cover. 
         FIG. 6  is an illustration of one embodiment of the impeller of the present invention. 
         FIG. 7A  is an illustration of a cutaway view of one embodiment of the present invention of the impeller positioned relative to the housing and showing the air movement through the housing during operation. 
         FIG. 7B  is an illustration of a view of one embodiment of the present invention showing the air movement through the housing during operation. 
         FIG. 8  is an illustration of a side view of one embodiment of the present invention of the impeller positioned relative to the housing and showing the air movement through the housing during operation. 
         FIG. 9  is an illustration of a side view of one embodiment of the present invention of the impeller positioned within the housing and the housing side cover. 
         FIG. 10  is an illustration of an alternate embodiment of the impeller of the present invention. 
         FIG. 11  is an side-view illustration of an embodiment of the impeller of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring primarily to  FIGS. 1 and 6 , the invention, which may be a blower  102  or the impeller  101  for use in a two-chamber contaminant-extracting blower  102 , includes a mounting hub  602  and a plurality of outwardly-radiating blades  603  affixed thereto sized to fit within the housing  103  of the blower  102 , and each blade  603  includes a second-chamber section, or lower main blade section  606 , extending from the mounting hub  602  and having a large cross-sectional area, a first-chamber section, or upper main blade section,  607  extending upward from the outer portion of the second-chamber section  606 , a first blade extension  614  formed by perpendicularly bending the portion of the blade  603  extending beyond the second-chamber section  606  and which extends from the first-chamber section  607  of the blade  603  into the second-chamber section  606  of the blade  603 , and a second blade extension  616  formed by perpendicularly bending a portion of the first blade extension  614  to be parallel to and outwardly extending from the blade  603  and which extends from the first-chamber section  607  of the blade  603  toward the end  615  of the first blade extension  614 . The embodiment may further include a rear circular plate  601  which may be solid to provide a surface against which contaminants may collide and then be redirected by blades  603 . 
     Referring to  FIG. 1 , the blower housing  103  includes a housing front wall  104 , a partition  106 , and a housing rear wall  105 , with at least the front housing wall  104  and the partition  106  having a circular opening therethrough with a common longitudinal axis  111 , and sized to permit the impeller  101  to pass therethrough. Housing  103  includes an intake opening  112  in communication with said front chamber  107 . Housing rear wall  105  may likewise have a similarly sized opening if the impeller  101  is to pass through the housing rear wall  105  to permit rear removal. When enclosed with the housing side wall  901  depicted in  FIG. 9 , the front housing wall  104  and the partition  106  form a front housing chamber, or front chamber,  107 . Likewise, when enclosed with the housing side wall  901  depicted in  FIG. 9 , the rear housing wall  105  and the partition  106  form a rear housing chamber, or rear chamber,  108 . The front chamber  107  is in communication with a front chamber outlet  109 , permitting air regarded as contaminant free, or clean, to exit the blower  102 . Similarly, the rear chamber  108  is in communication with a rear chamber outlet  110 , permitting contaminants and/or air regarded as containing or bearing contaminants, or dirty air, to exit the blower  102 . As depicted in  FIGS. 1-5  and  8 - 9 , the impeller  101  is positioned within the housing  103  and in front chamber  107  and the rear chamber  108 . A motor (not shown) may be positioned adjacent to or fixed to the housing  103 , such as at a motor mount  113 , and the motor shaft coupled to the impeller  101 . 
     Referring to  FIGS. 2 ,  3  and  4 , the blower  101  may further include an intake cover  201 , which is fixed to housing  103  adjacent the housing front wall  104 . The intake cover  201  covers the opening in housing front wall  104  and permits air flow to the front housing chamber  107  while protecting blower  102 . 
     Referring to  FIG. 3 , the intake cover  201  may permit air flow to the front housing chamber  107  through an opening near the housing  103  to limit the access to front housing chamber  107  to air only. 
     Referring to  FIGS. 3 and 6 , the impeller  101  includes a mounting hub  602  at its center, adapted to connect to a driven shaft. The impeller  101  further includes a plurality of outwardly-radiating blades  603  affixed thereto sized to a blade height  605  to fit within the housing  103  of the blower  102  and radiating outward from the center of the impeller  102 . Thus, each of the blades  603  has a blade height  605  sufficient to position the to top edge  604  of the blade  603  adjacent the housing front wall  104  when the impeller  101  is installed in the blower  102 . Each of the blades  603  is fixed in relation to the mounting hub and to each other, which may be, among other structures, by permanently affixing each blade  603  to the mounting hub  602  or by permanently affixing each blade  603  to a rear circular plate  601  and the mounting hub  602  to the rear circular plate  601 . 
     Each blade  603  has a main blade section  618  which may be considered to have a lower main blade section  606 , and an upper main blade section  607 . The main blade section  618  has a lower outer edge  612 , which is proximate the outer edge  608  of said rear circular plate  601 , when the circular plate  601  is used and has a lower main blade section bottom edge  610 , which is permanently attached to the rear circular plate  601 , when the circular plate  601  is used. Referring to  FIGS. 6 and 11 , each blade  603  may be inclined in the lower outer edge  612  of the impeller  101  in the direction  621  of rotation. This blade has an incline  619  in the range of 60 to 80 degrees, relative to the rear circular plate  601 , and optimally at 70 degrees. This incline  619  reduces noise and increases efficiency. 
     Returning to  FIG. 6 , the lower main blade section  606  of each blade  603  extends from proximate, or about or near to, the center of the rear circular plate  601  or the mounting hub  602 . The lower main blade section  606  has a length extending to proximate, or about or near to, the rear circular plate outer edge  608 , if the rear circular plate  601  is present, but in all respects, sized to fit within the openings of at least the housing front wall  104  and the partition  106  and potentially the housing rear wall  105 . Ideally, the lower main blade section  606  increases in height  609  distant from the center of the rear circular plate  601  or the mounting hub  602  but does not become so tall as to extend above the rear housing chamber  108 . Thus, the lower main blade section height  609  of each of lower main blade section  606  is preferably sufficient to position the lower main blade section  606  solely within the rear housing chamber  108 , and not within the housing front chamber  107  when the impeller  101  is installed in the blower  102 . 
     The upper main blade section  607  of each blade  603  extends upward from the lower main blade section  606  to the top edge  604  of the blade  603 . The upper main blade section  607  presents a trapezoidal cross section from the lower main blade section  606 , characterized by the upper blade section inner edge  617  and the upper blade section outer edge  622  both approaching a centerline  623  of the upper main blade section  607  towards the top edge  604  of the blade  603 , which centerline  623  is perpendicular to the rear circular plate  601 . The shape of the upper main blade section  607  of each blade  603  is thus sufficiently open at its center to create a pressure differential during rotation between the air contacting the upper main blade section  607  and the air contacting the lower main blade section  606 . 
     Each blade  603  also includes a first blade extension  614  extending along the upper main blade section  607  to along the lower main blade section  606 . Thus, the first blade extension  614  extends along the upper main blade section  607  and preferably covers the entirety of the upper main blade section  607  to ensure contaminants in the housing front chamber  107  are captured and redirected to the rear housing chamber  108 . The first blade extension  614  has an end  615  some distance from the rear circular plate  601 , providing, inter alia, an opening for carried contaminants to fall into the rear housing chamber  108 . Also differing from the prior art, this first blade extension  614  is integrally formed of the blade  603  by bending the material, rather than by welding. Preferably, the first blade extension  614  is bent to an angle of 90′ relative to the main blade section  618  and in the direction  621  of the rotation of impeller  101 , such that the first blade extension  614  leads the main blade section  618 . 
     Each blade  603  also includes a second blade extension  616  extending from the first blade extension  614  in a plane parallel to said main blade section  618  and extending away from said main blade section  618 . This second blade extension  616  extends along the outer edge of the first blade extension  614  to a second blade extension lower edge  624 , which is some distance from the first blade extension end  615 , and intermediate the upper main blade section  607  and said rear circular plate  601  or lower edge of the main blade section  618 , providing, inter alia, an opening for carried contaminants to fall into the rear housing chamber  108 . Also differing from the prior art, this second blade extension  616  is integrally formed of the blade  603  by bending the material, rather than by welding. Preferably, the second blade extension  616  is bent to an angle of 90′ relative to the first blade extension  614  so as to be parallel to the plane of the main blade section  618 . The second blade extension  616  has a second blade extension outer edge  625  which is parallel to said housing longitudinal axis  111 . 
     The blade top edge  604  of each blade  603 , and therefore the position of each blade  603 , may be maintained in relative position by permanently affixing a front circular plate  620 , with an orifice  626  therethrough to the blade top edge  604  of each blade  603 . Ideally the opening or orifice  626  is sufficiently sized to permit the sufficient inflow of air to the impeller  603  in operation. This may be accomplished by using a front circular plate which presents a surface no wider than the blade top edge  604  of each blade  603 . Alternatively, the blades  603  may be maintained in position by the use of struts  1001  between and among the blades  603 . 
     In operation, the main blade section  618 , the first blade extension  614  and the second blade extension  616 , in conjunction with the pitch or blade incline  619  of the impeller blade  603  and the speed of rotation of impeller  101  funnel residual impurities to the rear housing chamber  108  and does so more efficiently and provides quieter operation, in part because of the blade incline  619  of the blade  603  and because the first blade extension  614  and the second blade extension  616  are made part of the blade  603  with smooth radius bends of a single material sheet rather than a rough weld. This construction allows for a more laminar flow across the blade  603 . 
     Referring to  FIGS. 7A and 7B , when energized, the rotary drive drives the shaft mounted impeller  101 . As the impeller  101  turns, centrifugal forces build and the impeller blades  603  propel the air within the inside diameter of the impeller  101  into the front housing chamber  107  and the rear housing chamber  108 . The rotating blades  603  of the impeller  101  propel the air outward into the housing  103  creating a cyclonic current of air within both the front housing chamber  107  and the rear housing chamber  108  moving in the direction of rotation  621 . The current of air within the front housing chamber  107  is directed through the front chamber outlet  109  and directly into the area being cooled. While the current of air within the rear housing chamber  108  remains segregated and is directed through the rear chamber outlet  110 . As the air leaves the area within the inside diameter of the impeller  101 , a low pressure zone, or first impeller zone,  801  is created and new air rushes in through the intake cover to fill this low pressure zone  801 . This new, “dirty” air, depending on the operating environment, can contain water droplets, dust, dirt, sand, bugs, etc, collectively referred to as “impurities”. As the speed of rotation of the impeller  101  increases, the pressure drops and the speed of the incoming dirty air increases to fill this low pressure zone  801 . 
     The unique design of the impeller blades  603  creates two distinct pressure zones  801 ,  802  within the impeller  101 , the low pressure zone  801  and a second impeller zone  802  which helps separate the impurities. The portion of the blade  603 , including the upper main blade section  607  and portions of the first blade extension  614  and the second blade extension  616 , in the front housing chamber  107  is designed to direct more air into the front housing chamber  107 . Because more air is moving into the housing front housing chamber  107 , the pressures around the leading edge of the blades  603  over the low pressure zone  801  are lower than the pressures around the leading edge of the impeller blades  603  over the second impeller zone  802 . This area of lower relative pressure attracts more of the incoming airstream as it first enters. However, due to the abrupt change in direction needed to move into the front housing chamber  107 , the speed of the airstream, the mass and inertia of the impurities, only clean air is pulled directly in the low pressure zone  801 . The remainder of the airstream continues into the second impeller zone  802 . In the second impeller zone  802 , the incoming airstream meets the higher pressure area (relative to the low pressure zone  801 ), which begins to slow the forward motion of the air and deflect the airstream outward. The forward motion of the lighter air slows more quickly and the heavier impurities travel further into the second impeller zone  802 , due to their higher relative mass and inertia. In the second impeller zone  802 , the air and impurities are struck with the wider lower main blade section  606  of impeller blade  603 . The angular design combined with the speed of rotation act to move both the air and impurities in a downward and lateral motion toward the rear housing chamber  108 . As the impurities migrate down and out they enter the rear housing chamber  108  where they are caught in the cyclonic effect described earlier and washed around the housing and funneled to the rear chamber outlet  110  for the rear housing chamber and discarded. The heavier the impurity, the further it travels into zone two before being swept down and out by the pitch of the impeller. 
     A portion of the impurities may come into contact with the impeller blades  603  relatively high in the second impeller zone  802  where they may be drawn back toward the low pressure zone  801  by the lower pressures associated with it. When this happens the impurities migrate along the impeller blade  603  in an outward motion. Unlike the prior art, the unique shape of the impeller blade redirects the migration down toward the second impeller zone  802  and out through the rear chamber outlet  110 . 
     The impeller  101  further differs from the prior art by elimination of the notching present in many impellers to accommodate the partition  106 , which elimination permits removal of the impeller  101  from either side of the housing  103 . Previously, the use of a notch was necessary to improve the seal between the housing front chamber  107  and the rear housing chamber  108 , but prevented removal of the impeller  101  from the rearside  114 . The unique design of the impeller  101  of the present invention avoids the need for a notch by creating an isolating wind curtain around the air gap between the impeller blade  603  and the partition  106 . This isolating wind curtain is created by continuing the second blade extension  616  of the blade  603  dedicated to moving higher velocity air into the low pressure zone  801  into the rear housing chamber  108 , creating a curtain of higher speed air which runs across the gap and along the portion of the rear housing chamber  108  adjacent the partition  106 . This curtain of high speed air at a portion of rear housing chamber  108  seals the gap between the partition  106  and the impeller  101 , allowing for additional clearance. The additional clearance between the partition  106  and impeller  101  makes removal of impeller  101  via the rearside  114  possible. 
     The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof.