Patent Publication Number: US-8528510-B2

Title: Intake manifold

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This patent application claims priority to U.S. Provisional Patent Application Ser. No. 61/295,257 filed Jan. 15, 2010 which is hereby incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     Exemplary embodiments of the present invention relate to a V-configured 3-cylinder engine and, more particularly, to a low profile, compact intake manifold therefore. 
     BACKGROUND 
     Environmental sustainability, increasing global energy demands and the resulting rise in fuel cost and relatively new demand in developing economies for independent but less costly transportation is driving vehicle and powertrain designers towards smaller and more fuel efficient vehicles. It is not uncommon to find inline 3 and 4 cylinder engines powering many medium to small sized vehicles. However, these engines are length constrained by their inline cylinder configurations which operate to define the minimum vehicle architectural space in which they may be packaged. Narrow angle V-configured engines offer some additional packaging advantages by staggering pistons in offset banks, offering additional pistons and resulting power, without unnecessarily increasing the length of the engine package. However, engine height may suffer in such engines due to the use of a single cylinder head having a height beyond that required for an inline engine. 
     SUMMARY OF THE INVENTION 
     In an exemplary embodiment, an internal combustion engine comprising an engine block having a lower end closed by an oil pan and an upper end extending at an angle α from a rear of the engine block to a front thereof, a first, two-cylinder, cylinder head housing assembly reclined from vertical, towards the rear of the engine block, about an axis of the crankshaft by an angle β, a second, single-cylinder, cylinder head housing assembly oriented an angle γ, about an axis of the crankshaft, from the first, two-cylinder, cylinder head housing assembly has a low profile intake assembly configured to conduct combustion air to the first, two-cylinder, cylinder head housing assembly and the second, single-cylinder, cylinder head housing assembly. The low profile intake assembly comprises an intake manifold, a centrally extending plenum that extends axially in parallel to the crankshaft axis and defines a plenum axis, a first plurality of intake runners, in fluid communication with the centrally extending plenum, extend from the front side of the plenum and transition through a circumferential arc around the upper side thereof to fluidly couple with, and deliver combustion air to, the first, two-cylinder, cylinder head housing assembly, a single intake runner, in fluid communication with the centrally extending plenum, extends from the rear side of the plenum and transitions through a circumferential arc around the upper side thereof to fluidly couple with, and deliver combustion air to, the second, single-cylinder, cylinder head housing assembly and a zip tube configured to deliver combustion air to the central plenum at a location that is between one of the first plurality of intake runners and the single cylinder intake runner, wherein the zip tube approaches the central plenum from the front side and transitions through a circumferential arc around the upper side thereof to fluidly couple with, and deliver the combustion air to the central plenum. 
     In another exemplary embodiment, a low profile intake assembly for a 3-cylinder, V-configured engine comprises an intake manifold configured to conduct combustion air to a first, two-cylinder, cylinder head housing assembly and a second, single-cylinder, cylinder head housing assembly comprises a centrally extending plenum that extends axially in parallel to a crankshaft axis of the 3-cylinder, V-configured engine and defines a plenum axis, a first plurality of intake runners, in fluid communication with the centrally extending plenum, extend from the front side of the plenum and transition through a circumferential arc around the upper side thereof to fluidly couple with, and deliver combustion air to, the first, two-cylinder, cylinder head housing assembly, a single intake runner, in fluid communication with the centrally extending plenum, extends from the rear side of the plenum and transitions through a circumferential arc around the upper side thereof to fluidly couple with, and deliver combustion air to, the second, single-cylinder, cylinder head housing assembly and a zip tube, configured to deliver combustion air to the central plenum at a location that is between one of the first plurality of intake runners and the single cylinder intake runner, wherein the zip tube approaches the central plenum from the front side and transitions through a circumferential arc around the upper side thereof to fluidly couple with, and deliver the combustion air to the central plenum. 
     The above features and advantages, and other features and advantages of the invention are readily apparent from the following detailed description of the invention when taken in connection with the accompanying drawings. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       Other objects, features, advantages and details appear, by way of example only, in the following detailed description of the embodiments, the detailed description referring to the drawings in which: 
         FIG. 1  is side view of a V-configured 3-cylinder engine embodying features of the invention; 
         FIG. 2  is an end or side view of an intake manifold embodying features of the invention; and 
         FIG. 3  is a top or plan view of the intake manifold of  FIG. 2 . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
     Referring to  FIG. 1 , in an exemplary embodiment there is shown a V-configured 3-cylinder engine  3 . The engine  3  includes an engine block assembly  12  having an open lower portion or rim  14  that is closed by an oil reservoir or pan  16 . The upper end  18  of the engine block assembly  12  extends at an angle “α” from the rear  20  of the engine  3  to the front  22  of the engine and is closed by an engine block cover  24 . In an exemplary embodiment it is contemplated that the angle α may vary in a range from about 0° to about 45° depending upon the particular vehicle configuration and other application driven variables of the engine  3 . The combination of the engine block assembly  12 , the oil pan  16  and the engine block cover  24  defines a crankcase  26  that houses and supports a crankshaft  28 , and one or more balance shafts (not shown), for rotation therein. The crankshaft  28  is coupled by a belt, chain or gear drive to rotatably operate a camshaft defining a camshaft axis  33 . The camshaft acts upon pushrods (not shown) that extend into cylinder heads  78  and  120  for operation of valve gear (not shown) disposed therein. 
     In an exemplary embodiment, the crankshaft  28  comprises a crank snout  30  at a first end. The crank snout  30  extends outwardly of the front of the engine block assembly  12  and supports a crankshaft pulley  34  thereon. The crankshaft pulley  34  may be connected via an accessory drive belt (not shown) to various engine driven accessories such as an alternator  152 , an air conditioner compressor (not shown), an air pump  156  or a combination thereof. 
     In an exemplary embodiment two engine cylinders (not shown) are disposed within a first, two-cylinder, cylinder head housing assembly  72  for reciprocation therein. Additionally, a third engine cylinder (not shown) is disposed within a second, single-cylinder, cylinder head housing assembly  118  for reciprocation therein. Closing the upper end of the first, two-cylinder, cylinder head housing assembly  72  is a first cylinder head  78  and closing the upper end of the second, single-cylinder, cylinder head housing assembly  118  is a cylinder head  120 . 
     In an exemplary embodiment, the angling of the upper end  18  of engine block assembly  12  facilitates the angling or reclining from vertical (towards the rear of the engine block) of the first, two-cylinder, cylinder head housing assembly  72  about an axis of the crankshaft by an angle β, for the purposes of packaging the engine  3  in an efficient, low profile manner in a vehicle. In the embodiment illustrated in  FIG. 1 , the rearward bank angle β of the first, two-cylinder, cylinder head housing assembly  72  is about 70° from vertical. It is contemplated, however, that the rearward bank angle β may vary from about 30° to about 90° depending upon the particular vehicle configuration and other application driven variables. The third engine cylinder and second, single-cylinder, cylinder head housing assembly  118  may be oriented at an angle “γ” that is about 90 degrees from the two inline cylinders of the first, two-cylinder, cylinder head housing assembly  72  respectively. It is contemplated, however, that the angle “γ” may vary from about 25° to about 115°; again depending upon the particular vehicle configuration and other application driven variables. Such an orientation, as is illustrated in  FIG. 1 , will allow the V-configured 3-cylinder engine  3  to maintain a low profile while providing extra power that may be required for certain applications and is not available in a 2-cylinder, inline configuration. The single, relatively upright oriented second, single-cylinder, cylinder head housing assembly  118  is small enough and centrally located so as to result in the same vehicle packaging and interior space benefits that may be realized with an inline 2-cylinder engine. 
     A low profile intake assembly  80  is configured to conduct combustion air to the cylinder heads  78 ,  120 . Referring to  FIGS. 1-3 , the intake assembly  80  comprises an intake manifold  122  having an inlet runner or “zip tube”  124  for receiving metered combustion air through a throttle body  126 . The inlet runner  124  fluidly connects with and delivers combustion air to a centrally extending plenum  88  of the intake manifold  80 . The centrally extending plenum  88  extends axially in parallel to the crankshaft axis  31  and defines a plenum axis  134 . A plurality of intake runners  128 ,  130  and  132  are in fluid communication with the centrally extending plenum  88  and conduct combustion air to the cylinder heads  78  and  120 . More specifically, the intake runners  128  and  132  extend from the front side  138  of the plenum  88  and transition through a circumferential arc around the upper side  136  thereof to fluidly couple with and deliver combustion air to the two cylinders (not shown) of the first cylinder head  78  of the first, two-cylinder, cylinder head housing assembly  72 ,  FIG. 1 . Alternatively, the intake runner  130  extends from the rear side  139  of the plenum  88  and transitions through a circumferential arc around the upper side  136  thereof to fluidly couple with and deliver combustion air to the single cylinder (not shown) of the second cylinder head  120  of the second, single-cylinder, cylinder head housing assembly  118  providing a low profile, crossover configured intake manifold  122  with well balanced combustion airflow in a compact package. 
     Due to the unique configuration of the 3 cylinder V-configured engine  3 , the inlet runner or “zip tube”  124  delivers air to the central plenum  88  at a location that is between one of the 2-cylinder intake runners  128 ,  132  and the single cylinder intake runner  130 . In the exemplary embodiment of  FIG. 1  the inlet runner or “zip tube”  124  delivers air to the central plenum  88  at a location that is between the 2-cylinder intake runner  132  and the single cylinder intake runner  130  and in the exemplary embodiment of  FIGS. 2 and 3  the inlet runner or “zip tube”  124  delivers air to the central plenum  88  at a location that is between the intake runner  128  and the single cylinder intake runner  130 . The difference is defined solely by application and packaging constraints of the engine  3 . The inlet runner or “zip tube”  124  approaches the central plenum  88  from the front side  138  and transitions through a circumferential arc around the upper side  136  thereof to fluidly couple with and deliver combustion air to the central plenum; again providing a low profile, crossover configured intake manifold  122  with well balanced combustion airflow in a compact package. Referring again to  FIG. 1 , the intake manifold  122  assembles easily in the space between the first and second cylinder head housing assemblies  72  and  118  without extending above or adding to the height of the second, single cylinder head  120 . 
     While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the present application.