Abstract:
In an internal combustion engine having multiple cylinders, each cylinder defining a cylinder wall, and having a cylinder head, there being a piston movable axially within each cylinder to define a combustion zone between the piston top and the cylinder head, each cylinder having intake porting, the combustion comprising a manifold for delivering air to said combustion zones, via the intake porting at each cylinder, the manifold including air induction ducts, which are configured with branching to deliver substantially the same quantity of gas to each said porting.

Description:
This application is a continuation-in-part of Ser. No. 09/232,245, filed Jan. 19, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates generally to improvements in internal engine combustion, and more particularly to improvements in control of combustion gas flow in combustion chambers, and also to equalization of air or gas (fuel and air mixture) supply to the multiple combustion chambers in an engine. 
     There is need for such improvements in combustion gas flow within combustion chambers, and for distribution of pressurized air in equal quantities to such combustion chambers, for example to obtain better efficiency, greater power output, and smoother running of engines and reduced emissions. 
     SUMMARY OF THE INVENTION 
     It is a major object of the invention to provide such improvements, as referred to. 
     Basically, the invention is embodied in an internal combustion engine that has multiple cylinders, each cylinder defining a cylinder wall, and having a cylinder head, there being a piston movable axially within each cylinder to define a combustion zone between the piston top and the cylinder head, each cylinder having intake porting. In this combination the invention provides: 
     a) a manifold for delivering air to said combustion zones, via the intake porting at each cylinder, 
     b) said manifold including gas induction ducts, which are configured with branching to deliver substantially the same quantity of air to each said porting. 
     As will be seen, the ducts typically include branches, each branch supplying gas such as air to two of the intake ports. 
     In this regard, a standard 6-cylinder engine will have each cylinder receiving different amounts of air, when the air manifold is supplied with air at one entry point. The normal engine is supplied with 10 to 15 percent over supply of fuel in order to supply sufficient combustible mixture to all cylinders. 
     In the present invention, when the air supply from a turbocharger is changed from one supply duct or tube to three supply tubes, the manifold is considered as looped. One air supply duct or tube will supply air to two valves. Each valve will receive the same amount of air at the same air pressure under these conditions. 
     With the looped induction system used in an engine, all intake valves at the cylinders receive the same amount of air. The fuel supply can be reduced from the 10 to 15 percent over supply level to the exact (reduced) amount needed for stoichiometric fuel mixture. This does away with the rich and lean areas associated with the over supply of fuel. 
     Accordingly, another object is to provide an engine device blower, or turbocharger, delivering air to multiple of such ducts, each duct supplying air to at least two of intake ports. 
     Further, where there are six of such ports, three manifold ducts (each receiving the same amount of air) are caused to branch so that two branches from each of the three ducts delivers air to two of the ports, respectively. Such ducts have equal lengths, and the branches also have equal (shorter) lengths. 
     Multiple of such cylinders, heads, pistons, and dished recesses may typically be provided in the engine, each recess having an axial cross-section of substantially parabolic shape. Such an engine may be of Diesel type or of spark combustion type, as will be seen. 
     If of Diesel type, the engine typically has at least one fuel injector oriented to inject fuel into the combustion zone and toward the parabolic recess, whereby combustion explosion of the injected fuel causes combustion gases to be received by that recess and to be directed generally axially, as aforesaid. The recess may then be in the piston top, in the path of injected fuel flow. Two or more of such recesses may be employed in the piston top, as will be seen. 
     Another object is to provide a second dished recess in the other of the piston top and head, and configured to receive and direct gases at the time of compression and combustion to flow generally axially toward said one of the piston top and head. The second recess is also typically of substantially parabolic shape in axial cross-section. 
     If the engine employs spark plugs for ignition, the electrodes are located in the paths of combustion gas flow from the dished parabolic recesses, as will be seen. 
     These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which: 
    
    
     DRAWING DESCRIPTION 
     FIG. 1 is a section taken vertically and axially through an internal combustion engine cylinder and piston, and showing a parabolic recess; 
     FIG. 2 is a section taken vertically and axially through a piston, showing dual parabolic recesses; 
     FIG. 2 a  is like FIG. 2, but shows a modification; 
     FIG. 3 is a top plan view of a cylinder head showing provision of a pear shaped or oblong recesses outline, the recess being parabolic in elevation and in a direction that bisects dual valves; 
     FIG. 4 is a top plan view of a cylinder head showing four valves usable with a piston having a central parabolic recess as in FIG. 1 or recesses as in FIG. 2; 
     FIG. 5 is a view like FIG. 2, showing a parabolic recess in a piston, the recess offset relative to the piston axis; 
     FIG. 6 is a view like FIG. 5, showing the offset recess tilted relative to the piston axis; 
     FIG. 7 is a vertical axial section showing a central parabolic recess in the piston, and a central parabolic recess in the head, with two valves at the top of the parabolic recess in the head; 
     FIG. 8 is a side elevation view of multiple manifold ducts leading to intake valving; 
     FIG. 9 is an end view of the FIG. 8 ducting; 
     FIG. 10 is a schematic plan view showing a complete air induction system. 
     FIG. 11 is a view like FIG. 2 a  showing a modification; 
     FIG. 12 is a plan view of apparatus as shown in FIG. 11; and 
     FIG. 13 is an elevation showing separation of air or gas and particulate prior to induction. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows an internal combustion engine  10  having a cylinder  11  defining a cylinder wall  12 . A cylinder head  13  extends over the combustion chamber  14 , and the head has an inner surface  15  exposed to  14 . A piston  16  reciprocates up and down in the direction of a central axis  26 . The head has ports  17  and  18  for inflow of intake air, and for outflow of gaseous combustion products. Valves  19  and  20  are located at the ports and movable to open and close the ports to control such flow in timed relation to piston reciprocation, as is well know. The engine is further characterized by: 
     a) manifold means for delivering air to the combustion zone, 
     b) at least one of the piston top and the head defining a first dished recess configured to receive and direct gases at the time of combustion to flow generally axially toward the other of the piston top and head 
     Intake manifold ducting appears at  22 . In this example, the first dished recess, operating as referred to, is seen at  23 , in the piston top. Preferably, the recess  23  is parabolic, either laterally in the direction  24 , or in a lateral direction normal to  24 , or in both lateral directions, or all lateral directions about axis  26 . The focus of the parabola shown appears at  27 . The parabolic surface  23   a  of the recess  23  causes the gaseous pressure waves, received as during combustion, to travel back upwardly with increased axial direction, i.e. the waves travel with increased straightening, to achieve better mixing and burning of the air and fuel. Fuel is typically injected as at  29  generally toward the focus  27 , so that combustion waves at or near the focus traveling toward parabolic surface  23   a  will be reflected axially or generally axially upwardly. 
     The parabola can be designed to direct the reflected air energy to any point in the cylinder that is needed. 
     Combustion noise can be further reduced, by provision of a piston combustion chamber that uses two different recesses parabolic surfaces have two focal points. The two different sine waves produced upon reflection of combustion gases at the two parabolic surfaces will tend to cancel each other out and give a very quiet running Diesel is engine. The first parabola is typically a very shallow curve, the purpose of which is to direct more gases axially straight up the cylinder without bouncing off the cylinder walls. 
     FIG. 2 shows a piston  32  having dual. parabolic recesses  33  and  34  at its top surface  35  exposed to the combustion chamber  37 . Recess  33  intersects surface  35 , at  33   a  which maybe circular about central axis  36 . Recess  34  intersects the inner parabolic surface  33   b  of the recess  33 , at  34   a , which may be circular about central axis  37  of recess  34 . Axis  37  is offset from axis  36 . The focal points  33   d  and  34   d  of the two parabolic recesses are offset in the axial direction, and laterally, so as to cause the waves reflected generally axially from the parabolic surfaces  33   b  and  34   b  to tend to cancel one another, reducing engine noise. This is important for Diesel engines. The cylinder and valves appear at  133 ,  134  and  135 . 
     The second parabola is designed to give the exact dimensions to give the proper compression ratio for the engine. The squish band is shown at  39 . 
     FIG. 2 a  is like FIG. 2, but the two parabolas are co-axial. 
     The parabola  34   b  can take up to 60% of bore for best power and can be dimensioned to take up to 30% of bore, to lower emission even more. 
     Other type engines can also use parabola pistons and heads. For example, the combustion chambers on two-valve gasoline engines can use such parabolas (three parabolas). 
     Four-valve engines can also use the parabola on a concave piston (using the stroke axis as the focal point). 
     FIG. 3 shows an example of an engine cylinder head  40  having parabolic recessing. The parabolic recess  41  shown is pear shaped, as defined by recess edge  41   a  to accommodate two valves  42  and  43 , one of which may be for air-fuel mixture intake, and the other for discharge of combustion products. The recess  41  is parabolic between points  46  and  47  of intersection with the flat surface (squish band)  48  of the head, surrounding the recess  41 . A spark plug is shown as located at  49 . Such a parabolic recess in the head tends to reflect combustion gas compression waves generally axially toward the piston, for higher engine efficiency. 
     Certain new engines have four-valves per cylinder. These engines are relatively smaller, produce good horsepower, but gas fuel consumption mileage is the same as larger pear-shaped older engines. The new engines do not have the torque of the older engines and the new engines horsepower is limited as the castings are not strong enough to withstand 650 to 750 HP. 
     FIG. 4 shows an example of a four-valve head  50 , for use with a piston having a top recess, as in FIG.  1 . Note valves  51 - 54  in head surface  55 , and a central spark plug location. Parabolic recess elongated regions appear at  55  and  56 , one between lines or planes  55   a  and  56   a , and the other between  56   a  and  57   a , which are parallel. 
     FIG. 5 shows a piston in  60  axial section, with a parabolic recess  61  sunk in the piston top  62 . The recess is offset relative to the piston axis  63 . See recess axis  64 . Recess parabolic surface  61   a  is everywhere spaced below top  62 , and the recess periphery intersects annular wall  65  that extends generally axially, and about axis  64 , and that tends to further confine the pressure waves reflected by the parabolic surface  61   a , to travel axially. The recess axis  64  is parallel to and offset relative to axis  63 . 
     FIG. 6 is like FIG. 5, and bears the same identifying numbers; however, the parabolic recess axis  64   a  is angled relative to axis  63  (see angle α), and directed to the side  60   a  of the piston  60  closest to recess  61 . 
     Parabola formulas are as follows: 
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Parabola Formulas 
               
             
          
           
               
                   
                 Piston Combustion Chamber 
                 Piston Parabola 
               
               
                   
                   
               
               
                   
                 F = .5″ 
                 F − 3.2″ 
               
               
                   
                 x 2  = y4F 
               
               
                   
                 y = x 2   
               
               
                   
                 4f 
               
               
                   
                 y = x 2   
                 y = x 2   
               
               
                   
                 4x.5 
                 4 × 3.2 
               
               
                   
                 Volume of Parabola 
               
               
                   
                 V = ½π × a 2  × H 
                 a = radius at 
               
               
                   
                   
                 parabola 
               
               
                   
                   
                 H = height 
               
               
                   
                   
               
             
          
         
       
     
     Piston Combustion Chamber Parabola 
     2.4″ diameter 
     Focal Length 0.5″ 
     Piston Shape Parabola—Piston 4″ Diameter 
     Parabola 3.50″ diameter 
     Focal Length 3.2″ 
     Focal Volume of Piston Parabola and Combustion Chamber 
     45.5 c.c.=2.78 cu inches 
     
       
         
               
               
             
               
               
               
               
             
           
               
                   
               
               
                 Combustion Chamber Parabola 
                 Piston Parabola 
               
               
                   
               
             
             
               
                 F − .5 
                 F − 3.2 
               
               
                 y = x 2   
                 y = x 2   
               
               
                 4 × .5 
                 4 × 3.2 
               
             
          
           
               
                 x 
                 y 
                 x 
                 y 
               
               
                  .1 
                 .005 
                  .1 
                 .00078 
               
               
                  .2 
                 .02 
                  .2 
                 .003 
               
               
                  .3 
                 .045 
                  .3 
                 .007 
               
               
                  .4 
                 .08 
                  .4 
                 .0125 
               
               
                  .5 
                 .125 
                  .5 
                 .0195 
               
               
                  .6 
                 .180 
                  .6 
                 .028 
               
               
                  .7 
                 .245 
                  .7 
                 .038 
               
               
                  .8 
                 .320 
                  .8 
                 .05 
               
               
                  .9 
                 .405 
                  .9 
                 .063 
               
               
                 1.0 
                 .500 
                 1.0 
                 .078 
               
               
                 1.1 
                 .600 
                 1.1 
                 .0945 
               
               
                 1.2 
                 .720 
                 1.3 
                 .132 
               
               
                   
                   
                 1.5 
                 .1757 
               
               
                   
                   
                 1.6 
                 .200 
               
               
                   
                   
                 1.7 
                 .2257 
               
               
                   
                   
                 1.75 
                 .2392 
               
               
                   
               
             
          
         
       
     
     Volumes of Piston and Combustion Chamber Piston Combustion Chamber Volume (Parabola) 
     
       
         
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                 V + ½ π a 2  H 
                   
               
               
                   
                 F = .5 
                 a = radius of 
               
               
                   
                   
                 parabola 
               
               
                   
                 V − ½ 3.14 × (1.2) 2  × .72 
                 H = height of 
               
               
                   
                   
                 parabola 
               
               
                   
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 Piston Parabola - Volume 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 F − 3.2 
                   
               
               
                   
                 V = ½ 3.14 × (1.75) 2  × .2392 
               
               
                   
                 V − 1.5 cu. inches 
               
               
                   
                 F = .5 
                 V = 1.63 cu. inches 
               
               
                   
                 F − 3.2 
                 V − 1.15 cu. inches 
               
               
                   
                   
               
             
          
         
       
     
     Total Volume=2.78 cu. inches or =45.5 cu. Cm. 
     FIG. 7 shows a cylinder  80  and piston  81 . A shallow parabolic recess  82  is formed in the piston top  83 . A shallow parabolic recess  84  is also sunk in the inner surface  85  of the cylinder head  86 . Both recesses are directed toward the combustion chamber  87 , and assist one another in directing pressurized combustion product waves generally axially, in the direction of axis  88 . Intake and discharge valves  89  and  90  are located at ports  89   a  and  90   a  in the parabolic surface  84   a  of  84 . Fuel is injected at  140 . 
     FIGS. 8 and 9 show the provision of manifold means  100  including multiple ducts  101 - 103  located to deliver equal quantities of air (or air-fuel mixture) to intake valves, as referred to. Such tubes maybe looped. Intake ports appear at  150 - 155 , in casting  156 . Such equalization of air delivery is preferred. 
     Induction manifolds typically do not deliver the same amount of air to each cylinder. This is evidenced by the fact that the fuel supplied to each cylinder (injected into the engine) is 10 to 15% rich in order to cover all lean and rich running cylinders in the engine. 
     Installing the looped induction manifold will eliminate this problem. Each cylinder will receive the same amount of air in each cylinder. Fuel injection can be cut back by 10 to 15%. In turn, CO, HC and NOX will be reduced by the same amount. 
     FIG. 10 schematically shows a modified preferred system. A blower  110  delivers equal amounts of pressurized air to ducts  101 - 103  and such air can be cooled as by a cooler  110   a , to achieve higher density for increased horsepower. Each duct delivers air to a plenum  109  in the head casting  109   a , and each plenum supplies air to intakes  108 , via valves, of two cylinders. Fuel is injected at  107 , at each cylinder. Parabolic recesses are employed, in the combustion chambers, as disclosed herein. 
     FIGS. 11 and 12 show the use of twin and like fuel injectors, as at  150  and  151 , in each cylinder. The injectors have axes  150   a  and  151   a , such axes directed at angles Δ 1  and Δ 2  from the cylinder axis  152  and at opposite sides of that axis. The angles Δ 1  and ΔA 2  are typically the same, and are between 30° and 60° from axis  152 . 
     The fuel distribution path for one injector  151 , is at the right side of a vertical plane  153  through axis  152 , and normal to a plane  154  defined by the two axis  150   a  and  151   a . The fuel is injected at least substantially throughout the right side of the combustion chamber; and the injector  150  likewise injects fuel at least substantially throughout the left side of the combustion chamber. An injected fuel flow path also appears at  150   b  and  151   b , in FIG. 11, that path moving downwardly with the path forward boundary  155  moving downwardly toward two parabolic dished surfaces  33   b  and  34   b , as in FIG. 2 a . See arrows  155   a . The downward convexity of moving surface  155  correlates generally to the downward convexities  33   b  and  34   b , of the parabolic recesses in the cylinder head, whereby the benefits of better mixing and burning of air and fuel reduced emissions, and more straightening, as referred to above, are enhanced, as by symmetry provided by twin injections. The piston and cylinder are indicated at  158  and  159 , and the head at  160 . 
     FIG. 13 shows the inclusion in the engine systems, as described above, of a cyclone type separator and muffler  170  receiving products of combustion from the engine, as via exhaust valving, schematically indicated at  171 . The separator/muffler has a conical shell wall  172 , closed at the top, and open at the bottom  173 . The inlet pipe  174  from the valving  171  is directed generally tangentially with the shell, whereby gases and particles spin around vertical axis  175 , with particles centrifugally thrown outwardly to travel downwardly at  176  to the bottom outlet  173 . A heating grid  177  or collector receives the particles from outlet  173 , and acts to collect and burn the combustible particles, to eliminate them. The separated exhaust gases travel at  178  back up into an exhaust pipe  179  to exhaust to atmosphere. A conical baffle  180  within the shell interior maintains separation between paths  176  and  178 . 
     Results 
     2-Parabolas Looped Induction 
     1. Particulate emissions will be lowered due to complete burning of the fuel. 
     2 Parabolas 
     2. NO, will be reduced and proper head shape will allow engine to run with less-heat. 
     6 Twin Injectors 
     3. CO and HC will be lowered as fuel will travel 50% less distance to side wall and air will mix better with fuel as the distance for fuel to travel in order to mix with air is cut 50% 
     4. Power is up 5 to 10% 
     5. Acceleration will be much better. 
     By adding all the increases together a smaller engine can be built which by its construction will be more efficient, again lowering emissions. 
     Further aspects of the invention are summarized below. 
     Parabola Combustion Chamber Shape 
     When a parabola shape is used for a recess in a piston or cylinder, as described herein, it will cause parallel travel of the pressure waves as they travel up the bore under compression. As the fuel fires, energy will be reflected by the cylinder head to the parabolic recess in the piston and will be reflected parallel back up the cylinder, spreading throughout the combustion area. This will decrease the differentiation of rich and lean areas in the exhaust gases, mixing being much better, and resulting in lowering the non-combusted emissions. 
     Reason for Lower Emission 
     1. The squish band—the fuel is squeezed into the combustion chamber. 
     2. Center fired spark plug—cuts down on the distance that the fuel or burning fuel has to travel to mix with the air under compression in the combustion chamber. The injected fuel is much heavier than the compressed air and will push the air out of the way. When the piston approaches T.D.C., the air and fuel tend to burn with some areas lean and some areas rich. With the proper control of the burning fuel, much of the differentiation between lean and rich areas can be eliminated by squeezing the air/fuel into the center combustion chamber. The closer to T.D.C. the piston travels, the cleaner the engine will run and the more power it will produce. With twin injectors, the fuel is injected by the two fuel injectors so that the burning fuel zones will meet at the center of the bore and meet at the back walls-forcing the compressed air to mix with the burning fuel. The injection units area directional as described herein. 
     With twin injectors, the distance the burning fuel travels is about 75 percent less than with a center fire injector. This retards the injection timing and allows more fuel to be added. This in turn produces: more torque and horsepower along with a much cleaner running engine, at a lower RPM.