Abstract:
A blower for a downdraft cooktop that includes a blower housing, having a top portion and a bottom portion, which includes an inlet that can be fluidly coupled to a downdraft cooktop and an outlet for removing air from the blower housing, a fan located between the input and the outlet of the blower housing, a motor having a rotor with a shaft, having a top portion and a bottom portion, and a stator, wherein the bottom portion of the rotor is operatively attached to the fan, a rotatable member operatively attached to the top portion of the rotor, and a motor housing enclosing the motor, having a top portion, a bottom portion, at least one inlet opening and at least one outlet opening, wherein air for cooling the motor is drawn through the motor housing without utilizing the air located within the blower housing.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority of U.S. Provisional Patent Application No. 61/582,030 filed Dec. 30, 2011, which is hereby incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Typically, blowers for gas and electric downdraft cooktop applications rely on blower dilution air for cooling. There is a significant issue with utilizing dilution air from the blower motor as an intake for cooling the motor since system resistance can result in reversing the motor which expels grease laden air into the cooking environment. Due to insufficient blower performance, a known commercial solution is to use a separate blower for a gas cooking unit and a separate blower for an electric cooking unit associated with the same stove because of insufficient blower performance. In addition, it is important for a blower to be able to pass the Underwriters Laboratories Inc. (“UL”) Articulated Finger Probe Test, which was designed to consider accessibility by small children, as well as the UL Knife Probe Test to determine human access to moving or rotating parts. 
     The present invention is directed to overcoming one or more of the problems set forth above. 
     SUMMARY OF INVENTION 
     The present invention is directed to a blower for a downdraft cooktop. The blower includes a blower housing, having a top portion and a bottom portion, which includes an inlet that can be fluidly coupled to a downdraft cooktop and an outlet for removing air from the blower housing, a fan located between the input and the outlet of the blower housing, a motor having a rotor with a shaft, having a top portion and a bottom portion, and a stator, wherein the bottom portion of the rotor is operatively attached to the fan, a rotatable member operative attached to the top portion of the rotor, and a motor housing enclosing the motor, having a top portion, a bottom portion, at least one inlet opening and at least one outlet opening, wherein air for cooling the motor is drawn through the at least one inlet opening of the motor housing through the rotation of the rotatable member and dispelled through the at least one outlet opening of the motor housing so that cooling of the motor does not require direct access to air located within the blower housing. 
     The present invention is directed to a blower for a downdraft cooktop. The blower includes a blower housing, having a top portion and a bottom portion, which includes an inlet that can be fluidly coupled to a downdraft cooktop and an outlet for removing air from the blower housing, a fan located between the input and the outlet of the blower housing, a motor having a rotor with a shaft, having a top portion and a bottom portion, and a stator, wherein the bottom portion of the shaft for the rotor is attached to the fan and the top portion of the shaft for the rotor is attached to a rotatable member, and a housing for the motor having a top support member, at least one cooling band, a bottom support member, wherein the top support member, the at least one cooling band and the bottom support member are connected together to enclose the rotor and the stator of the motor, and an outer enclosure that is positioned above the rotatable member, wherein the rotatable member can draw air through at least one inlet opening in the outer enclosure in fluid relationship with the top support member and the stator before exiting through at least one outlet opening in the outer enclosure and the rotatable member can draw air through at least one inlet opening in the bottom support member in fluid relationship with the rotor and the stator prior to exiting through at least one outlet opening in the lower portion of the motor housing so that cooling of the motor does not require direct access to air located within the blower housing. 
     Still yet another aspect of the present invention is that a method for utilizing a blower for a downdraft cooktop is disclosed. The method includes rotating a rotor shaft, having a top portion and a bottom portion, with a motor, enclosed in a housing, wherein the bottom portion of the rotor shaft is operatively attached to a fan located within a blower housing, having an inlet and an outlet, where the fan is capable of drawing air from a downdraft cooktop through the inlet into the blower housing and then through the outlet of the blower housing and the top portion of the rotor shaft is operatively attached to a rotatable member to draw air into the motor housing through at least one inlet opening of the motor housing and dispel the air through at least one outlet opening of the motor housing for cooling of the motor without directly accessing the air from within the blower housing. 
     These are merely some of the innumerable aspects of the present invention and should not be deemed an all-inclusive listing of the innumerable aspects associated with the present invention. These and other aspects will become apparent to those skilled in the art in light of the following disclosure and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       For a better understanding of the present invention, reference may be made to the accompanying drawings in which: 
         FIG. 1  is a bottom perspective view of a preferred embodiment of a blower for a standard downdraft gas and/or electric cooktop in accordance with the invention; 
         FIG. 2  is a top perspective view of a preferred embodiment of a blower for a standard downdraft gas and/or electric cooktop in accordance with the invention; 
         FIG. 3  is a side elevational view of a preferred embodiment of a blower for a standard downdraft gas and/or electric cooktop in accordance with the invention, with the mechanical attachment mechanisms for the blower housing removed; 
         FIG. 4  is a bottom view of a preferred embodiment of a motor assembly associated with a blower for a standard downdraft gas and/or electric cooktop in accordance with the invention; 
         FIG. 5  is a perspective view of a preferred embodiment of a motor assembly associated with a blower for a standard downdraft gas and/or electric cooktop in accordance with the invention; 
         FIG. 6  is a cut-away front view through the longitudinal axis of a preferred embodiment of a blower for a standard downdraft gas and/or electric cooktop in accordance with the invention; 
         FIG. 7  is a cut-away front view through the longitudinal axis of a preferred embodiment of a blower for a standard downdraft gas and/or electric cooktop in accordance with the invention; 
         FIG. 8  is identical to  FIG. 6  with the addition of air flow indicated both into and out of the motor assembly for the blower for a standard downdraft gas and/or electric cooktop in accordance with the invention; and 
         FIG. 9  is identical to  FIG. 7  with the addition of air flow indicated both into and out of the motor assembly for the blower for a standard downdraft gas and/or electric cooktop in accordance with the invention. 
     
    
    
     Reference characters in the written specification indicate corresponding items shown throughout the drawing figures. 
     DETAILED DESCRIPTION OF THE INVENTION 
     In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as to obscure the present invention. 
     The preferred embodiment of a blower for a standard downdraft gas and/or electric cooktop is generally indicated by numeral  10  in  FIG. 1 . There is a housing for the blower that is generally indicated by numeral  12  that has a top portion  14  and a bottom portion  16 . There is an inlet  18  that draws in smoke, fumes and other airborne discharge created during the cooking process. A wide variety of geometric shapes will suffice, but a circular shape is preferred. There is an inlet screen  20  that prevents physical objects from going into the blower  10 . There is an outlet  22  for removing smoke, fumes and other airborne discharge created during the cooking process from the blower  10  that was received through the inlet  18 . 
     Referring now to  FIG. 2 , the housing  12  can be in a wide variety of shapes and sizes with the preferred shape being cylindrical with an outer extension  24  extending toward the outlet  22 . A wide variety of geometric shapes will suffice for the outer extension  24 , but a rectangular shape is preferred. Referring now to  FIGS. 1 and 3 , the blower housing  12  also includes sidewalls  26  that extend between the top portion  14  and the bottom portion  16 . There is an upper flange member  28  for the top portion  14  that extends over the sidewalls  26  and a lower flange member  30  that also extends over the sidewalls  26 . There are a series of attachment mechanisms, e.g., screws,  32  in the bottom portion  16  of the blower housing  12  that provide for attachment of the blower  10  to a standard downdraft gas and/or electric cooktop (not shown). 
     Referring now to  FIGS. 1 and 2 , an illustrative, but nonlimiting, example of the outlet  22  includes a coupler  34  that attaches to the outer extension  24 . The outlet  22  can be a myriad of geometric shapes and is preferably circular, while the outer extension  24  can also be a myriad of geometric shapes and is preferably rectangular. The coupler  34  transitions between the outlet  22  and the outer extension  24  with the illustrative, but nonlimiting, example being a circular shaped outlet  22  to a rectangular outer extension  24 . A wide variety of securing mechanisms  36 , e.g., screws, can be used to secure the outlet  22  to the outer extension  24 , with the illustrative, but nonlimiting example, of slots  38  in the coupler  34  that allow securing mechanisms  36 , e.g., screws, to attach to the outer extension  24  in threaded holes (not shown) located therein. An illustrative, but nonlimiting, number of securing mechanisms  36  include four (4) with two (2) located on top of the outlet  22  and two (2) located on the bottom of the outlet  22 . 
     Referring now to  FIG. 2 , there are preferably a plurality of mechanical attachment mechanisms  40 , e.g., nut and bolt combinations, which connect the top portion  14  of the blower housing  12  to the bottom portion  16  of the blower housing  12  resulting in the sidewalls  26  being secured in place. 
     As shown in  FIGS. 1 ,  2 ,  3 ,  4 , and  5 , there is a motor assembly that is generally indicated by numeral  42 , which includes a motor housing  44 , which is otherwise known as a cooling case. There is a conduit box  46  for receiving electrical power that is attached to the motor housing  44 . There is a ground lug  49  shown in  FIG. 4 . 
     A wide variety of motors  64 , shown in  FIGS. 6 ,  7 ,  8 , and  9 , may be utilized with the motor assembly  42  of the present invention. A preferred illustrative, but nonlimiting, example of motor  64  is a variation is the permanent-split capacitor (“PSC”) motor. This is also known as a capacitor start and run motor. This motor utilizes a starting capacitor inserted in series with the startup windings or second windings (not shown) connected to a power source, e.g., 115 Volts, 60 Hertz, from the conduit box  46  through a capacitor  48 , creating an LC circuit which is capable of a much greater phase shift along with run windings (not shown). 
     The capacitor  48  ranges from 3 to 25 microfarads, e.g., 7.5 microfarads at 370 Volts AC, is connected in series with the “start” windings (not shown) and remains in the circuit during the run cycle. By changing taps on the “running winding” (not shown) for the motor  64 , shown in  FIGS. 6 through 9 , there can be multiple and distinctive speeds, e.g., low speed at 1775 r.p.m. at 0.23 Amperes and 26 Watts for idle and 1000 r.p.m. at 0.78 Amperes and 85 Watts under loaded conditions, medium speed at 1778 r.p.m. at 0.32 Amperes and 36 Watts for idle and 1200 r.p.m. at 0.96 Amperes and 107 Watts under loaded conditions and high speed at 1784 r.p.m. at 0.50 Amperes and 55 Watts for idle and 1400 r.p.m. at 1.26 Amperes and 142 Watts under loaded conditions. Motor wiring connections (not shown) though the conduit box  46  include a wire for common, a wire for ground, a separate wire for each of the three speeds and two wires for the capacitor  48 . There is distinctive speed separation with a PSC motor. An illustrative, but nonlimiting, example of an permanent-split capacitor (“PSC”) motor  64  for the present invention, includes No. 70903281, Type U90B1, which is manufactured by Regal Beloit Corporation (Fasco Motors Group), having a place of business at 200 State Street, Beloit, Wis. 53511-6254. 
     The conduit box  46  also includes a cord strain relief  50 , shown in  FIGS. 4 ,  6  and  8 . There is a lid  52  for the conduit box  46  that is attached to the conduit box with a first attachment mechanism  54 , e.g., threaded screw, and a second attachment mechanism  56 , e.g., threaded screw, as shown in  FIGS. 1 ,  2 ,  3 ,  4  and  5 . 
     Referring now to  FIGS. 1 ,  3  and  5 , there is a top portion  58  of the motor housing  44  and a bottom portion  60  of the motor housing  44 . Referring now to  FIGS. 4 and 5 , the bottom portion  60  of the motor housing  44  includes a plate  62  with a plurality of vents  68 , e.g., sixteen (16) for providing cold air intake into the motor housing  44  for cooling. The plate  62  is attached to the bottom portion  60  of the motor housing  44  by a series of spot welds  86 , e.g., Typ four (4), or any of a wide variety of attachment mechanisms. The vents  68  can be any of wide variety of shapes and sizes with the preferred illustrative, but nonlimiting, configuration being a tapered oval. 
     Referring now to  FIGS. 6 and 7 , the motor  64  includes a rotatable rotor  70 , having a top portion  72  and a bottom portion  74 . The bottom portion  74  of the rotor  70  can be removably attached to a receptacle  76 . The receptacle  76  is fixedly or removably attached to a fan  78  that is rotatable. Therefore, the smoke, fumes and other airborne discharge created during the cooking process will come into the inlet  18  past the curved sidewalls  19  and into the inlet screen  20  by the rotation of the fan  78  and then out of the blower housing  12  that is sealed. This includes the top portion  14 , bottom portion  16 , and sidewalls  26  of the blower housing  12  through the outlet extension  24  through the outlet  22 . Therefore, the motor  64  and the associated cooling system is completely independent and does not use the air having the smoke, fumes and other airborne discharge from the downdraft cooking process to cool the motor  64 . Since this cooling system for the motor  64  is completely independent, there is no fluctuation with regard to system resistance to the blower  10 . Consequently, when system resistance is encountered, the motor  64  does not provide warm grease laden air when rotation of the rotor  70  is reversed. This results in a significant improvement over prior systems when grease laden air cannot escape the blower  10  and then contaminate the room. Moreover, a HEPA filter (not shown) can be utilized in a ductless application. As shown in  FIG. 1 , the fan  78  can be any of a myriad of geometric shapes and configurations, with the illustrative and nonlimiting example being that of a hollow cylindrical structure with a plurality of protruding ridges  80 . 
     Referring again to  FIGS. 6 and 7 , the bottom portion  74  of the rotor  70 , having a first flange member  81 , is rotatably held in position by a first sealed bearing  82  and the top portion  72  of the rotor  70 , having a second flange member  84 , is rotatably held in position by a second sealed bearing  83 . When the bottom portion  74  of the rotor  70  passes between the bottom portion  60  of the motor housing  44  to the top portion  14  of the blower housing  12 , there are a plurality of connectors  88 , e.g., four (4) connector bolts and associated nut combinations. 
     As best shown in  FIG. 4 , there is a finned end ring venturi  77  positioned around a shaft seal  79  to enclose the bottom portion  74  of the rotor  70  passes between the bottom portion  60  of the motor housing  44  to the top portion  14  of the blower housing  12 . The shaft seal  79  prevents the grease laden air from escaping from the blower housing  12  and into the consumer&#39;s environment but does not have any influence on the cooling system for the motor  64 . The shaft seal  79  is sandwiched between the bottom portion  60  of the motor housing  44  and blower housing  12  but does not touch the bottom portion  74  of the rotor  70 , e.g., shaft. The smaller the distance between the bottom portion  60  of the motor housing  44  to the top portion  14  of the blower housing  12 , the easier it will be to pass the Underwriter&#39;s Laboratories (hereinafter, “UL”) Articulating Probe Test and the UL Knife Probe test, which is a significant advantage of the present invention. There are a series of raised embossments  89 , e.g., four, that operate as spacers and elevate the bottom portion  60  of the motor housing  44  in relationship to the top portion  14  of the blower housing  12  and are secured to the top portion  14  of the blower housing  12  by a series of attachment mechanisms  93 , e.g., four screws. 
     The rotor  70  also includes a middle portion  90 . Preferably, but not necessarily this middle portion  90  extends outward from the rotor  70  and includes fins  92 . Preferably, but not necessarily, this middle portion  90  of the rotor  70  is cylindrical. This middle portion  90  of the rotor  70  is surrounded by the stator  94  and is rotatable therein. The top portion  72  of the rotor  70  is attached to a rotatable member  96  that has a top portion  98  and a bottom portion  100 , where the top portion  98  of the rotatable member  96  has a smaller radius than the bottom portion  100  of the rotatable member  96  with a curved arc between the top portion  98  of the rotatable member  96  and the bottom portion  100  of the rotatable member  96  to form an umbrella fan as an illustrative, but nonlimiting example. The rotatable member  96  is preferably, but not necessarily cylindrical. 
     There is a top support member  102  that is attached to the second sealed bearing  83  and a bottom support member  104  that is attached to the first sealed bearing  82 . Attached to the top support member  102  and the bottom support member  104  is a cooling band  106  that surrounds the outside of the stator  94 . The bottom support member  104  is located between the first sealed bearing  82  and the spacers  89 , e.g., four (4) raised embossments located on top portion  14 . The top support member  102 , bottom support member  104 , and cooling band  106  are all preferably, but not necessarily, cylindrical. The windings (not shown) on the stator  94  are electrically connected (not shown) through the conduit box  46 . The conduit box  46  is adjacent to the cooling band  106 . The top portion of the motor housing  44  includes an outer enclosure  108  that extends over the top of the rotatable member  96  and is adjacent to the capacitor  48 . There is a sleeve member  110  located between the cooling band  106  and the outer enclosure  108  with a first attachment mechanism, e.g., threaded screw  122  that connects the sleeve member  110  to the outer enclosure  108 . There is a second attachment mechanism, e.g., threaded screw  124  that connects the sleeve member  110  to the outer enclosure  108 . 
     The capacitor  48  can be secured to the outer enclosure  108  by a wide variety of mechanisms. An illustrative, but nonlimiting, example includes a strap  112  that is attached to the outer enclosure  108  by a first attachment mechanism, e.g., threaded screw,  114 , and a second attachment mechanism, e.g., threaded screw  116 , as shown in  FIG. 2 . 
     Mounted to the top of the outer enclosure  108  is an air intake cap  118  that provides locations for cooling air to be delivered to the inside of the motor housing  44 . The air intake cap  118  provides a plurality of air vents  120 , as shown in  FIG. 2 . A preferred, but nonlimiting, number of air vents would include three (3); however, any number may suffice. 
     Referring now to  FIGS. 8 and 9 , first cooling air stream  126  that is drawn into the outer enclosure  108  by the rotatable member, e.g., umbrella fan,  96  and then splits into a second cooling air stream  128  that passes through the stator  94 , a third cooling air stream  130  that passes over the outside of the stator  94 , and a fourth cooling air stream  132  that passes between the outer enclosure  108  and the cooling band  106 . The second cooling air stream  128 , the third cooling air stream  130 , and the fourth cooling air stream  132  then recombine to form a fifth cooling air stream  134  that exits the motor housing  44 . There is a sixth cooling air stream  136  that enters through the plurality of vents  68 , which appear to be hidden, in the bottom portion  60  of the motor housing  44  and flows around the finned end ring venturi  77  with splitting and reconnecting to join and combine with the fifth cooling air stream  134 . There is a seventh cooling air stream  138  that enters through the plurality of vents  68 , which also appear to be hidden, in the bottom portion  60  of the motor housing  44  and flows around finned end ring venturi  77  with splitting and reconnecting and then exit through an opening in the conduit box  46  as an eighth cooling air stream  140 . There is a ninth cooling air stream  142  that is drawn into the outer enclosure  108  by the rotatable member, e.g., umbrella fan,  96  and then splits into a tenth cooling air stream  144  that passes through the stator  94 , an eleventh cooling air stream  146  that passes over the outside of the stator  94 , and a twelfth cooling air stream  148  that passes between the outer enclosure  108  and the cooling band  106 . The tenth cooling air stream  144 , the eleventh cooling air stream  146 , and the twelfth cooling air stream  148  then recombine to form a thirteenth cooling air stream  150  that exits the motor housing  44 . 
     The blower  10  reduces vibration significantly from prior systems, e.g., sixty-five percent (65%), noise, e.g., twenty-five percent (25%) and energy, e.g., twenty percent (20%). This blower  10  works in an elevated ambient, and only due to the completely integrated nature of this cooling system can this blower  10  operate. 
     Furthermore, it should be understood that when introducing elements of the present invention in the claims or in the above description of the preferred embodiment of the invention, the terms “have,” “having,” “includes” and “including” and similar terms as used in the foregoing specification are used in the sense of “optional” or “may include” and not as “required.” Similarly, the term “portion” should be construed as meaning some or all of the item or element that it qualifies. 
     Thus, there have been shown and described several embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims that follow.