Abstract:
A modified air intake mechanism for an internal combustion engine. The air intake mechanism includes an air passageway that contains a fixed vane located in a plane that is parallel to the air flow within the passageway. More specifically, the vane is stationary and is located in the air horn or the air intake passageway of the cylinder head.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims the benefit under 35 U.S.C. §119(e) of prior U.S. Provisional Application No. 60/177,771 filed Jan. 24, 2000; which is hereby incorporated by reference. 
     
    
     
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
         [0002]    This invention has been created without the sponsorship or funding of any federally sponsored research or development program.  
         BACKGROUND OF THE INVENTION  
         [0003]    The present invention is directed to the air intake features of an internal combustion engine. For most internal combustion engines, ambient air is mixed with a vaporized fuel. The air fuel mixture is introduced into the working cylinder portion of the engine. Power can be increased by increasing air flow into the cylinder. One way to increase air flow to an internal combustion engine is to add a “velocity stack” or “air horn” to a carburetor or fuel injector. A “velocity stack” is a generally cone-shaped device that is open to the outside and directs airflow to the air-fuel system. These devices are more commonly used on engines that are intended for extra power including automobile, motorcycle or power boat engines. The velocity stack has a relatively large inlet opening and a relatively small outlet opening. Generally, when a velocity stack is used on an engine, an air filter is not used.  
           [0004]    Many engine designs include an adjustable vane in the air horn, air intake port of the cylinder head or both. The vane functions as a valve to control the air flow to accommodate variations in power needs. In one known engine design, the vane in the air intake passageway of the cylinder head is fixed within the passageway. The vane gradually twists so that the cross-section area of the air intake passageway gradually narrows toward the inlet port of the cylinder. Therefore, the primary effect of the vane is to direct the air flow.  
           [0005]    Many of the prior art air intake devices that employ vanes restrict air flow in the intake port in such a way that the air flow is biased toward one side of the valve opening and it&#39;s velocity is maintained. In each case, a circular air flow is created within the combustion cylinder around the cylinder axis. This increases mixing of the charge in the cylinder for best fuel efficiency. Therefore, the prior art air intake devices which employ a vane increase air turbulence to increase fuel efficiency not power. These and other difficulties experienced with the prior art air horn and cylinder head designs have been obviated by the present invention.  
           [0006]    A principle object of the present invention is to provide an air intake system for an internal combustion engine that will produce an increased air flow to the engine and a resulting increase in horsepower.  
           [0007]    A further object of the invention is the provision of an air intake system for an internal combustion engine that includes a modification in the path of the air flow leading to the engine.  
           [0008]    Another object of the invention is the provision of a vane structure in either the air passageway of the air horn or cylinder head for reducing turbulence and increasing air flow to the cylinder.  
         BRIEF SUMMARY OF THE INVENTION  
         [0009]    In general, the invention consists of a modified air intake mechanism for an internal combustion engine. The air intake mechanism includes an air passageway that contains a fixed vane located in a plane that is parallel to the air flow within the passageway. More specifically, the vane is stationary and is located in the air horn, an air intake passageway of an air horn or the cylinder head. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The character of the invention, however, may be best understood by reference to the accompanying drawings, in which:  
         [0011]    [0011]FIG. 1 is a top plan view of an air horn which forms part of the air intake of a motorcycle engine and embodying the principles of the present invention;  
         [0012]    [0012]FIG. 2 is a vertical cross-sectional view taken along line II-II of FIG. 1 and looking in the direction of the arrows;  
         [0013]    [0013]FIG. 3 is a vertical cross-sectional view taken along line III-III of FIG. 1 and looking in the direction of the arrows;  
         [0014]    [0014]FIG. 4 is a bottom plan view of a modified velocity stack for an internal combustion engine and embodying the principles of the present invention;  
         [0015]    [0015]FIG. 5 is a vertical cross-sectional view taken along line  5 - 5  of FIG. 4 and looking in the direction of the arrows;  
         [0016]    [0016]FIG. 6 is a vertical cross-sectional view taken along line  6 - 6  of FIG. 4 and looking in the direction of the arrows;  
         [0017]    [0017]FIG. 7 is a cross-sectional view of the cylinder head of an internal combustion engine equipped with an air horn of the present invention; and  
         [0018]    [0018]FIG. 8 is a cross-sectional view similar to FIG. 7 without an air horn and having a vane in the air intake passageway of the cylinder head. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0019]    Referring to FIGS.  1 - 3 , there is shown an “air horn” or “velocity stack”, generally indicated by the reference numeral  10 , for use on some types of engines. Air horn  10  has a frusto conical wall  12  that has an inlet opening  14  at one end of the air horn and an outlet opening  16  at the opposite end of the air horn. Wall  12  of the air horn flares outwardly as at  18  at the inlet opening  14 . The wall  12  defines an internal air passageway  19  that extends from the inlet opening  14  to the outlet opening  16 . A mounting flange  21  is located adjacent the outlet opening  16 . A vane  20  is located in the passageway  19  and is located in a plane that is parallel to the air flow path. The vane  20  spans the passageway  19  in a lateral direction and extends nearly the entire length of the passageway  19  in the longitudinal direction. Air horn  10  is located on the outside of the motorcycle and is operatively connected to the carburetor of the motorcycle. Under circumstances other than for an internal combustion engine, the presence of a vane in an air passageway would be detrimental to air flow. The vane reduces the cross-sectional area of the passageway and creates a drag to air flow. This is confirmed by bench tests which show that air flow through the air horn is reduced when a vane is added to the chamber of the air horn. However, tests also showed that when the air horn is operatively connected to an internal combustion engine, air flow and horsepower are both increased. It is believed that an internal combustion engine causes a vortex to develop in the air inlet passageways leading from the outside to the cylinders of the engine. It is also believed that the presence of the vane within the air horn prevents a vortex from forming in the passageway of the air horn. Although the vane also impedes air flow, the disruption of, or prevention of a vortex results in a net gain in air flow to the engine. Best results for increased air flow and the resulting increase in horsepower have been achieved by having the vane extend substantially along the entire length of the air horn. Substantial beneficial results have also been obtained with a vane having a length which is at least equal to the smallest diameter of the air horn.  
         [0020]    Referring to FIGS.  4 - 6 , there is shown a second type of air horn of a type commonly used on motorcycles and has been modified in accordance to the present invention. The air horn shown in FIGS.  4 - 6  is generally indicated by the reference numeral  25  and has a frusto conical side wall  26  that extends from an inlet opening  28  to an outlet opening  30 . The wall  26  flares outwardly at  32  at the inlet opening  28 . A mounting flange  33  is located adjacent the outlet opening  30 . An air filter  34  is located at the inlet opening  28 . A vane  36  is located in the passageway  35 . A side wall  26  defines a passageway  35 . The vane  36  extends transversely across the entire width of the passageway  35  as shown in FIG. 5 and extends longitudinally from the filter  34  to the outlet opening  30 . It is preferred that the vane  36  extends substantially the entire length of the air horn  25 . However, a substantial increase in air flow and a resulting increase in horsepower are obtained from a longitudinal vane length which is at least equal to the smallest diameter of the air horn, i.e. diameter of the outlet opening  30 .  
         [0021]    [0021]FIG. 7 shows the air horn  10  of the present invention applied to the cylinder head of an internal combustion engine. The cylinder head is indicated by the reference numeral  37  and includes an air intake passageway  38 . The cylinder head  37  is shown affixed to the combustion end of a cylinder  39 . A carburetor  43  is located between the air horn  10  and the cylinder head  27 . The carburetor  43  includes a passageway  45  which connects the passageway  19  of the air horn  10  to the air intake port  38 .  
         [0022]    Referring to FIG. 8, there is shown a modification of the invention wherein the air horn is not utilized. A vane  50  similar to vane  20  of the air horn is located within the air intake passageway  38 . The vane  20  spans the entire width of the air intake passageway  38  and extends longitudinally from the opening  44  of the air intake passageway  38 . The longitudinal length of the vane  50 , is at least equal to the diameter of the inlet opening  44 . Tests have shown that the inclusion of a vane in the passageway  38 , such as that shown in FIG. 8 or passageway  19  of the air horn as shown in FIG. 7, results in increased air flow to the cylinder of the internal combustion engine, with a resulting increase in horsepower for a wide range of rpm of the engine. Test results appear to indicate that, without a vane, a vortex is created in the air flow to the internal combustion engine. Test results also appear to show that the presence of a vane in the path of the air flow between the cylinder of the engine and the opening to ambient air eliminates or disrupts the vortex sufficiently to increase the air flow to the engine with a resulting increase in horsepower.