Abstract:
An air intake housing and flow enhancing plate for a carburetor with a fluted and contoured air intake opening that flushly aligns with and matches the shape of the carburetor air intake opening. The low profile plate is made of metal for durability and heat resistance. The centrally located air intake opening of the plate has a clover leaf or undulating shape that conforms to the shape of the carburetor air intake opening. The plate is secured directly over the top of the carburetor, and extends radially outward to provide a larger area for securing its fiberglass housing. The housing holds a conventional ring shaped air filter located around the carburetor air intake opening. The plate provides smooth transitions between surfaces to decrease turbulence and improve air flow.

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    This invention pertains to a metal plate for securing a fiberglass air intake housing over a contoured carburetor air intake opening, where the air intake opening of the plate is contoured to match the shape of the carburetor intake opening and is also fluted to thereby improve air flow into the carburetor and engine performance. 
       BACKGROUND OF THE INVENTION 
       [0002]    The carburetor of an internal combustion engine controls the air and fuel mixture entering the cylinders of the engine for ignition. Obtaining a desired fuel-to-air ratio helps the engine operate more efficiently and produce more power. Engine power can be increased by increasing the amount of fuel entering each cylinder. However, simply increasing the amount of fuel to increase power is not enough. Problems occur when the fuel-to-air ratio is too “rich” or too “lean.” 
         [0003]    Increasing air flow into the carburetor to mix with the fuel is often problematic, particularly in racecar applications. The air intake opening of conventional carburetors allow a certain volume of air to enter the carburetor in a given amount of time. The volumetric flow rate of the carburetor can limit how much fuel can be mixed with the air entering the cylinders, and how much power the engine will produce. Air scoops and cowl intakes located by the windshield help direct compressed air into the carburetor when the vehicle is moving. Compressed air increases the amount of air entering the carburetor. More air means more fuel can be mixed with that air, which allows the engine to produce more power. Still, air scoops and cowl intakes only go so far to increase air flow into a carburetor. 
         [0004]    Turbochargers and superchargers are frequently added to increase airflow into a carburetor. These devices typical compress air from about 14.7 psi to about 22 psi to provide about 50 percent more air into the engine. Yet, these devices are frequently inappropriate. They are expensive and prone to braking. In addition, while cowl intakes or air scoops are permitted for many racing events, turbochargers and superchargers are not. 
         [0005]    The present invention is intended to solve these and other problems. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0006]    The present invention pertains to an air intake housing and flow enhancing plate for a carburetor. The plate has a fluted and contoured air intake opening that flushly aligns with and matches the shape of the carburetor air intake opening. The low profile plate is made of metal for durability and heat resistance. The centrally located air intake opening of the plate has a clover leaf or undulating shape that conforms to the shape of the carburetor air intake opening. The plate is secured directly over the top of the carburetor, and extends radially outward to provide a larger area for securing its fiberglass housing. The housing holds a conventional ring shaped air filter located around the carburetor air intake opening. The plate provides smooth transitions between surfaces to decrease turbulence and improve air flow. 
         [0007]    An advantage of the present carburetor air intake plate is its increased volumetric air flow to the carburetor. This increase in flow rate is believed to be a result of the shape of the plate, which eliminates surface discontinuities along the air flow path of travel. In particular, the rounded or fluted and contoured shape of its air intake opening flushly mates with the carburetor air intake opening to reduce turbulence and increase the volumetric flow rate into the carburetor. The following test results were achieved, and dynamometer testing confirmed these results. 
         [0000]    
       
         
               
             
               
               
               
             
               
             
               
               
               
             
               
             
               
               
               
             
           
               
                   
               
             
             
               
                 20″ water column w/90% flow 
               
               
                 Using 3½″ tall air filter 
               
             
          
           
               
                   
                 Present housing and air flow enhancing plate 
                 717 CFM 
               
               
                   
                 Conventional housing and securement plate A 
                 720 CFM 
               
               
                   
                 Conventional housing and securement plate B 
                 714 CFM 
               
             
          
           
               
                 20″ water column w/90% flow 
               
               
                 Using 3″ tall air filter 
               
               
                 (common for most applications) 
               
             
          
           
               
                   
                 Present housing and air flow enhancing plate 
                 718 CFM 
               
               
                   
                 Conventional housing and securement plate A 
                 711 CFM 
               
               
                   
                 Conventional housing and securement plate B 
                 704 CFM 
               
             
          
           
               
                 40″ water column w/90% flow 
               
               
                 (representing a motor with more horsepower) 
               
               
                 Using 3″ tall air filter 
               
             
          
           
               
                   
                 Present housing and air flow enhancing plate 
                 927 CFM 
               
               
                   
                 Conventional housing and securement plate A 
                 912 CFM 
               
               
                   
                 Conventional housing and securement plate B 
                 910 CFM 
               
               
                   
                   
               
             
          
         
       
     
         [0008]    Another advantage of the present plate is that the increase in the volumetric air flow rate increases the amount of fuel that can be mixed with the air entering the cylinders without creating too rich a fuel mixture. The extra fuel increases the power the engine produces, which is particularly important in race car applications. An engine equipped with the present housing and air flow enhancing plate design produces about 5 to 8 horsepower more than if it were using a conventional housing and securement plate design. 
         [0009]    A further advantage of the present plate is the flush coplanar alignment of its inner perimeter and air intake opening with the sidewall of the contoured carburetor air intake opening. The structure of this contoured inner perimeter of the plate as well as its fluted upper end and flat lower end are readily machined with a three axis (3-axis) milling machine. The inner perimeter of the plate is thicker than the radius of the rounding or fluting of the plate along its upper surface, which creates a flat region proximal the bottom surface of the plate. This flat region is contoured to flushly align in coplanar registry with the sidewall forming the contoured carburetor air intake opening. The fluting and flush, contoured, coplanar alignment of the inner perimeter of the plate with the contoured carburetor air intake opening. 
         [0010]    A still further advantage of the present air intake plate is its low profile and radial structure. The low profile design allows it to fit beneath the hood of a car with no or minimal modification to the car hood. The radial structure allows the plate to fit centrally over the top of the carburetor, which allows for use with conventional ring shaped air filters. The centrally located and radially shaped plate allows the weight of the plate, filter and housing to be evenly distributed around the plate and carburetor. 
         [0011]    A still further advantage of the present carburetor air intake plate is its ability to accommodate its use with an air scoop or induction cowl intake duct. In this way, the plate facilitates compression of the air prior to entering the carburetor, which further increases the amount of fuel that can be mixed with the air. This design further increases the power of the engine, which is particularly important for racing applications. 
         [0012]    A still further advantage of the present carburetor air intake plate invention is its ease of installation. The lower surface of the plate is shaped to fit over the top of a conventional carburetor. A circular rib extending from the plate provides a socket to snuggly secure the plate around the perimeter of the carburetor. A conventional wing nut is used to secure the plate and housing in place. An air intake housing or scoop is easily secured to the plate via screws and uniformly spaced slots around the perimeter of the plate. This allows the plate or the entire housing to be easily and quickly installed and removed, which is particularly important for racing applications. 
         [0013]    Other aspects and advantages of the invention will become apparent upon making reference to the specification, claims and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1A  is a perspective view of a vehicle with an internal combustion engine having a four barrel carburetor, and equipped with a conventional air filter and intake housing and securement plate, and showing an enlargement of the plate secured to the carburetor and the contoured hourglass shape of the carburetor air intake opening. 
           [0015]      FIG. 1B  is a cross-sectional view of  FIG. 1A  showing the conventional securement plate secured to the carburetor with its rounded inner perimeter extending over the top of the carburetor, and showing surface discontinuities that disrupt the flow of air along its path of travel. 
           [0016]      FIG. 2  is a perspective view of a vehicle with an internal combustion engine having a four barrel carburetor equipped with the inventive housing and air flow enhancing plate. 
           [0017]      FIG. 3  is a perspective view of an internal combustion engine having a four barrel carburetor equipped with the inventive housing and air flow enhancing plate. 
           [0018]      FIG. 4  is a perspective view of the present inventive housing and air flow enhancing plate mounted over the top of a four barrel carburetor. 
           [0019]      FIG. 5  is a cross-sectional view of  FIG. 4  taken along line  5 - 5  showing the flow enhancing plate mounted over the top of the carburetor and the air intake and filter housing secured to the radial perimeter of the plate, with the plate forming smooth transitions between surfaces along the air flow path of travel. 
           [0020]      FIG. 6  is an exploded view of the housing and air flow enhancing plate. 
           [0021]      FIG. 7  is an enlarged, top perspective view of the securement and air flow enhancing plate and its fluted and contoured air intake opening. 
           [0022]      FIG. 8  is an enlarged, bottom perspective view of the securement and air flow enhancing plate and its fluted and contoured air intake opening, as well as the sleeve flange for securing the plate to the top of the carburetor. 
           [0023]      FIG. 9  is a cross-sectional view of  FIG. 7  taken along line  9 - 9  showing the shape of the main body of the securement and air flow enhancing plate, its fluted and contoured air intake opening, its lower carburetor mounting rib and its radial flange for securing its housing. 
           [0024]      FIG. 10  is a top view of the air flow enhancing plate secured over the top of a four barrel carburetor showing its central alignment with the carburetor and the flush alignment of the contoured air intake openings of the plate and carburetor. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0025]    While this invention is susceptible of embodiment in many different forms, the drawings show and the specification describes in detail a preferred embodiment of the invention. It should be understood that the drawings and specification are to be considered an exemplification of the principles of the invention. They are not intended to limit the broad aspects of the invention to the embodiment illustrated. 
         [0026]    Conventional vehicles  5  with internal combustion engines  7  use carburetors  10  to mix liquid fuel with outside air as shown in  FIGS. 1A and 1B . The resulting vaporized air-fuel mixture is sent to the cylinders of the engine  7  to ignite and power the vehicle  5 . Carburetors  10  typically have two or four fuel and air mixing barrels  11  and two overflow tubes  12 . The carburetor  10  has a generally flat, horizontal top surface  13  with a centrally located, hourglass or clover leaf shaped air-fuel mixing chamber  14 . The continuous arcuate sidewall or throat  15  of the chamber  14  is generally vertical or perpendicular to its top surface  13  to form an edge that creates an air flow disruption or discontinuity. The barrels  11  are symmetrically located inside the hourglass or clover leaf shaped chamber  14  when viewed from above. One barrel  11  is located in each leave of the chamber  14 . The contoured air inlet opening  16  allows air to flow down into the barrels  11  of the carburetor  10 . The hourglass shape of the opening  16  has four outermost points  17 . The top surface  13  of the carburetor  10  forms a flat upper rim around its mixing chamber  14 . The perimeter of this rim  13  is formed by the round outer sidewall surface  18  of the carburetor  10 . A lip  19  extends radially out from the side surface  18  to support an air intake and filter housing. 
         [0027]    Carburetors  10  are provided with an air intake and filter housing  20  that holds a conventions ring shaped air filter  21  to filter the outside air before it enters the centrally located carburetor  10 . Racecars and other high performance vehicles typically use an air intake housing or air scoop to take in higher pressure or compressed air produced by the movement of the car  5 . The housing  20  has lower and upper mating shell portions  22  and  23  made of fiberglass. The housing  20  forms a free or open end  24  for taking in air and a carburetor end  25  with a domed portion  26  that holds the air filter  21 . The lower portion  22  of the housing  20  includes a metal securement plate  27  that is fastened to the fiberglass housing. 
         [0028]    The metal plate  27  has a downwardly extending shoulder and round central opening. The shoulder is sized and shaped to fit around the outside wall  18  of the carburetor  10  and rest on its radially extending flange  19 . The shoulder includes a gasket (not shown) to help form an air tight seal. The plate  27  extends over the top  13  of the carburetor  10 , and its round central opening is sized so that the plates rounded end forming the opening intersects the four outermost points  17  of the hourglass shape of the contoured carburetor air intake opening  16  as shown in the enlarged view of  FIG. 1A . The remainder and majority of the plate terminates short of the opening  16  to create edged shelve surfaces or discontinuities  30  that disrupt the air flow as shown in  FIG. 1B . These surface discontinuities  30  along the air flow path between the housing  20  and carburetor  10  disrupt the air flow  29 , and create a more turbulent air flow. A center bolt  28  and wing nut  29  hold the fiberglass housing  20  and metal plate  29  in place against the top  13  of the carburetor  10 . 
         [0029]    The present invention pertains to an air intake housing and its securement and air flow enhancing plate shown generally by reference numbers  40  and  50 , respectively, as shown in  FIGS. 2-10 . The air intake housing  40  is formed by upper and lower duct portions  41  and  42 . The housing  40  has an open or free end  43  for taking in outside air, and a carburetor end  44  for securing to the top of the carburetor  10 . The carburetor end  44  has a slot  45  for holding a conventional ring shaped air filter  21 . This end  44  also has a rounded domed portion  46  to lower the housing  40  inside the engine compartment of the car  5 . The domed portion  46  includes a flat, horizontal radial flange  47  with uniformly spaced securement slots  48 . The inner or free end of the flange  47  forms a round central opening  49  having a diameter of about seven inches. 
         [0030]    The securement and air flow enhancing plate  50  has a generally disc shape to give it a low profile to minimize the height of the air intake housing  40  relative to the engine  7 . The plate  50  has a wedge shaped main body  51  with lower and upper surfaces  52  and  53 . A flat outer rim  55  extends radially from the main body  51 . The flat rim  55  is located between its outer edge or perimeter  56  and a lip  57  located proximal the main body  51 . Slots  58  are formed through the rim  55  at uniform intervals to allow screws (not shown) to secure the plate  50  to the flange  47  of the housing  40 . The plate  50  is inserted into housing opening  49  and secured along flange  47  via these screw fasteners. 
         [0031]    The lower surface  52  of the plate  50  includes a downwardly extending rib  61  with a lower end  62  that forms a mounting socket  65  sized and shaped to receive the sidewall  18  and top  13  of the carburetor  10 . The lower end  62  of the rib  61  abuts the radial flange  19 , and the lower surface  52  of the plate  50  rests on the top surface  13  of the carburetor  10 . The center bolt  28  and wing nut  29  hold the housing  40  and metal plate  50  in place. A gasket can be used to help form an air tight seal. 
         [0032]    The main body  51  has a wedge shaped or inclined portion  71  with a thinner outer portion  72  of about 0.2 inches, and a thicker inner portion  73  of about 0.7 inches as best shown in  FIG. 9 . The upper surface  53  of the inclined portion  71  slopes radially downward toward its outer perimeter to help maintain its low profile. The thicker inner portion  73  has a smoothly curved transitional or rounded portion  75  that culminates at its inner perimeter  77 . The machined rounded portion  75  has a constant radius of preferably about ½ inch curvature. This rounding radius remains constant around the entire inner perimeter  77  of the plate  50 , and leaves a vertical flat region  78  of about ¼ inch around the inner perimeter  77 . Notches  79  are formed on opposite sides of the inner perimeter  77  to accommodate the overflow tubes  12  of the carburetor. 
         [0033]    The inner perimeter  77  of the plate  50  is contoured to match the shape of the sidewall  15  of the carburetor chamber  14  as best shown in  FIGS. 5 ,  6  and  10 . The perimeter  77  is shaped so that arcuate air intake opening  90  flushly aligns with the arcuate or hourglass shape of the air intake opening  16  of the carburetor  10 . The undulating or hourglass shape of opening  90  is flushly aligned with the hourglass shaped opening  16  of the carburetor  10 . The flat region  78  of the plate is in flush registered coplanar alignment with the vertical sidewall  15  forming the chamber  14 . 
         [0034]    The undulating nature of the inner perimeter  77  of the plate  50  provides inner contoured areas  85  of the plate  50  that extend inside the outermost points  17  of the hourglass shaped carburetor opening or throat  16 . These contoured areas  85  avoid the shelving effect and formation of discontinuities found in conventional plate designs. The hourglass or undulating shape of the perimeter  77  produces alternating wider  86  and narrower  87  contoured areas  85  that extend inwardly of the outermost points  17  of the hourglass shaped carburetor air intake opening  16 . The flat lower surfaces  52  of these areas  85  rest on the top surface  13  of the carburetor  10 . The round outer perimeter  56  and an arcuate inner perimeter  77  of the plate  50  give it a somewhat ring-like disc or donut shape. 
         [0035]    While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the broader aspects of the invention.