Patent Publication Number: US-10767608-B2

Title: Air intake assembly for motorcycle

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/711,025 filed Sep. 21, 2017, the entire contents of which are incorporated herein by reference. 
    
    
     FIELD OF THE DISCLOSURE 
     The present disclosure relates to motorcycles, and more particularly to an air intake assembly for a motorcycle. 
     BACKGROUND 
     Conventional high-flow air intake assemblies for motorcycles may include a tubular conduit supporting an exposed cone filter. The tubular conduit extends from a side of a motorcycle and toward a rider&#39;s leg once the rider is positioned on the motorcycle. Such air intake assemblies may extend from the side of the motorcycle so as to interfere with a comfortable riding position for some riders. 
     SUMMARY 
     In one aspect, an air intake assembly includes a filter element and an intake conduit having a first end supporting the filter element. The first end forms an inlet opening having a first shape and a second end being adapted for attachment to an engine. The second end forms an outlet opening having a second shape different than the first shape of the inlet opening. The intake conduit also includes a body having an inner wall defining a passageway coupling the inlet and outlet openings. The inner wall has a maximum lateral dimension measured transverse to a central axis of the passageway within a plane that interests both the inlet and outlet openings. The maximum lateral dimension is located adjacent the outlet opening. 
     In another aspect, an air intake assembly includes an air filter subassembly having a base end adapted to couple to an intake conduit. The air filter subassembly includes a first filter element having a front end and a rear end. The air filter subassembly also includes a velocity stack coupled to the rear end of the first filter element to inhibit relative movement between the velocity stack and the first filter element. The velocity stack includes an interior surface having an inlet opening and a non-circular outlet opening. The interior surface tapers from the inlet opening to the outlet opening. 
     Other aspects of the disclosure will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of a motorcycle including an air intake assembly according to an embodiment of the disclosure. 
         FIG. 2  is a top view of the motorcycle of  FIG. 1  with a portion of the motorcycle in cross-section taken along  2 - 2  of  FIG. 1  illustrating a rider&#39;s leg positioned adjacent the air intake assembly. 
         FIG. 3  is an exploded view of the air intake assembly of  FIG. 1 . 
         FIG. 4  is an outlet end view of a conduit of the air intake assembly of  FIG. 1 . 
         FIG. 5  is an inlet end view of the conduit of  FIG. 3 . 
         FIG. 6  is a perspective view of an outlet end of a velocity stack subassembly of the air intake assembly of  FIG. 3 . 
         FIG. 7  is a perspective view of an inlet end of the velocity stack subassembly of  FIG. 6 . 
         FIG. 8  is an end view of the outlet end of the velocity stack subassembly of  FIG. 6 . 
         FIG. 9  is a cross-sectional view of the air intake assembly taken along  9 - 9  of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. 
       FIG. 1  illustrates a motorcycle  10  including a drive assembly  14 , a frame  18 , a front fork assembly  22 , a swing arm or rear fork assembly  26 , a front wheel  30 , a rear wheel  34 , a seat  38 , and a fuel tank  42 . The motorcycle  10  defines a longitudinal or vertical plane  46  (e.g., parallel to a XY plane as best shown in  FIGS. 1 and 2 ) extending between the front and rear wheels  30 ,  34  and oriented substantially perpendicular to ground  50  that supports the motorcycle  10  when the motorcycle  10  is in an upright position as illustrated in  FIG. 1 . The motorcycle  10  also defines a lateral or horizontal plane  54  (e.g., parallel to a XZ plane as best shown in  FIG. 1 ) that intersects an air intake assembly  82  coupled to the motorcycle  10 , as discussed in more detail below. In some embodiments, the horizontal plane  54  is oriented substantially parallel to the ground  50  when the motorcycle  10  is in the upright position. 
     The front fork assembly  22  is pivotally coupled to the frame  18  at a front end of the motorcycle  10  and rotatably supports the front wheel  30 . The front fork assembly  22  includes a pair of handle bars  58  (only one handle bar  58  is shown in  FIGS. 1 and 2 ) for steering the motorcycle  10 . The rear fork assembly  26  is coupled to the frame  18  at a rear end of the motorcycle  10  and rotatably supports the rear wheel  34 . The seat  38  and footrests  60  (e.g., foot pegs) are coupled to the frame  18  to support a rider  62  positioned on the motorcycle  10  ( FIG. 2 ). The fuel tank  42  is also coupled to the frame  18  and provides fuel to the drive assembly  14 . 
     With continued reference to  FIG. 1 , the drive assembly  14  is coupled to the frame  18  beneath the seat  38  between the front wheel  30  and the rear wheel  34  of the motorcycle  10 . The drive assembly  14  includes an internal combination engine  66  and a transmission  70 . The engine  66  is a V-twin engine including a first or front cylinder block  74  and a second or rear cylinder block  78 . The engine  66  is operable to drive the rear wheel  34  via the transmission  70 , for example at a plurality of different selectable speed ratios, in order to move the motorcycle  10  relative to the ground  50 . 
     An air intake assembly  82  is also illustrated in  FIG. 1  that is selectively attached to the engine  66  with the horizontal plane  54  intersecting the air intake assembly  82  (e.g., at section line  8 - 8 ). Particularly, the air intake assembly  82  mounts to a lateral side of the engine  66 . With reference to  FIGS. 2 and 3 , the air intake assembly  82  includes a bracket  86 , a conduit  90  generally shaped as an oblique elbow, and an air filter subassembly  94 . The bracket  86  is mountable to the engine  66  ( FIGS. 1 and 2 ) via, for example, by two bolts and includes threaded bracket apertures  98  positioned around an engine air inlet port  102  of the bracket  86 . The bracket  86  can establish fluid communication for the air intake assembly  82  to a throttle body inlet (not shown) to provide throttled air for combustion in the engine  66 . 
     As best shown in  FIG. 3 , the conduit  90  includes an outlet or first end  106  that interfaces with the bracket  86 , an inlet or second end  110  that interfaces with the air filter subassembly  94 , and a body  114  that extends between the outlet  106  and the inlet  110 . The illustrated outlet  106  includes an outlet flange  118  having a planar outlet flange surface  122  ( FIG. 4 ) that abuts the bracket  86 . In the illustrated embodiment, the planar outlet flange surface  122  is substantially parallel to the vertical plane  46  of the motorcycle  10 . The outlet flange  118 —and ultimately the conduit  90 —is fixed to the bracket  86  by bracket fasteners  126  (e.g., bolts;  FIG. 3 ) extending through outlet flange apertures  130  of the outlet  106  to engage the threaded bracket apertures  98 . In some embodiments, the conduit  90  can be manufactured from carbon fiber, aluminum, or the like. In addition, a first bracket gasket  134  is positioned between the bracket  86  and the planar outlet flange surface  122  to provide an air-seal between the bracket  86  and the conduit  90 , and a second bracket gasket  136  is positioned downstream of the bracket  86  to provide an air-seal between the bracket  86  and the engine  66 . 
     With reference to  FIG. 4 , the outlet  106  also includes an outlet opening  138 . In the illustrated embodiment, the outlet opening  138  is circular-shaped and includes an outlet radius  142  of about 1.30 inches, which matches the geometry of the engine air inlet port  102  of the bracket  86 . As such, the area of the outlet opening  138  is about 5.33 inches squared. In other embodiments, the outlet radius  142  can be more or less than 1.30 inches, which will increase or decrease the area of the outlet opening  138 , respectively. In further embodiments, the outlet opening  138  can be of different geometry (e.g., ellipse, square, rectangular, triangular, etc.). 
     With reference to  FIG. 5 , the inlet  110  includes an inlet opening  146  and an inlet flange  150  having a planar inlet flange surface  154  surrounding the inlet opening  146 . The illustrated planar inlet flange surface  154  is obliquely oriented relative to the planar outlet flange surface  122 . In other words, the planar inlet flange surface  154  is oriented at an oblique angle relative to the vertical and horizontal planes  46 ,  54 . In other embodiments, the planar inlet flange surface  154  can be oriented perpendicular to the planar outlet flange surface  122 . In the illustrated embodiment, the inlet opening  146  is non-circular (e.g., ellipse-shaped) and includes a minor diameter or dimension  158  of about 2.43 inches and a major diameter or dimension  162  of about 3.53 inches. As such, the area of the inlet opening  146  is about 6.73 inches squared. In the illustrated embodiment, a ratio of the area of the inlet opening  146  over the area of the outlet opening  138  is about 1.26. In some embodiments, the area of the inlet opening  146  is plus or minus 20 percent of the area of the outlet opening  138 , and can be equal to the area of the outlet opening  138  in some constructions. In other embodiments, the area of the inlet opening  146  may vary from the area of the outlet opening  138  by more than 20 percent, for example, by increasing or decreasing at least one of the minor dimension  158  and the major dimension  162  compared to the illustrated embodiment. In the illustrated embodiment, the minor dimension  158  is a horizontal dimension of the inlet opening  146 , and the major dimension  162  is a vertical dimension of the inlet opening  146 . In particular, the minor dimension  158  is oriented relative to the horizontal plane  54  at an angle less than about 6 degrees, and the major dimension  162  is oriented relative to the vertical plane  46  at an angle less than about 16 degrees ( FIG. 5 ). In other embodiments, the minor dimension  158  can be perpendicular to the planar outlet flange surface  122  (e.g., parallel to the horizontal plane  54 ), and the major dimension  162  can be parallel to the planar outlet flange surface  122  (e.g., parallel to the vertical plane  46 ). 
     With reference to  FIGS. 4, 5, and 9 , the body  114  is curved and defines a central axis  166  extending between center points of the inlet  110  and the outlet  106 . The central axis  166  can be a 2-dimensional or 3-dimensional curve, and can have a constant curvature or different portions with different curvatures, including linear portions. In the illustrated embodiment, the sharpest bend in the central axis  166 , defined by the smallest radius, is positioned adjacent the outlet  106  or at least closer to the outlet  106  than the inlet  110  ( FIG. 9 ). However, no portion of the central axis  166  includes a bend greater than 90 degrees so that the central axis  166  does not include any sharp bends or curves between the inlet  110  and the outlet  106 . 
     With continued reference to  FIGS. 4, 5, and 9 , when the conduit  90  is arranged so that the lateral plane  54  intersects both the inlet opening  146  (i.e., the center point of the inlet opening  146  as illustrated in  FIG. 9 ) and the outlet opening  138 , a first lateral dimension  167  of the body  114  is defined in the lateral plane  54 , transverse to the central axis  166 , in a portion of the body  114  adjacent the inlet  110  ( FIG. 9 ). Likewise, a second lateral dimension  168  of the body  114  is defined in the lateral plane  54 , transverse to the central axis  166 , in another portion of the body that is adjacent the outlet  106  ( FIG. 9 ). Furthermore, the body  114  includes a first height dimension  169  ( FIG. 5 ) that is transverse to the lateral plane  54  and the central axis  166  at an axial location of the first lateral dimension  167 . The body  114  also includes a second height dimension  170  ( FIG. 4 ) that is transverse to the lateral plane  54  and the central axis  166  at an axial location of the second lateral dimension  168 . Because the inlet opening  146  is ellipse-shaped and the outlet opening  138  is circular-shaped, the first lateral dimension  167  is less than the second lateral dimension  168  and the first height dimension  169  is greater than the second height dimension  170  (e.g., the body  114  is an ellipse-shaped body adjacent the inlet opening  146  and transitions into a circular-shaped body adjacent the outlet opening  138 ). In the illustrated embodiment, the inlet opening  146  includes a first shape (e.g., ellipse-shaped), the outlet opening  138  includes a second shape (e.g., circular-shaped), and a portion of the body  114  between the inlet opening  146  and the outlet opening  138  has a different shape (e.g., ellipse-shaped) than the second shape of the outlet opening  138 . In other embodiments, the inlet opening  146  and the outlet opening  138  can be the same shape (e.g., circular-shaped) with a portion of the body  114  between the inlet opening  146  and the outlet opening  138  being of a different shape (e.g., ellipse-shaped). 
     With continued reference to  FIG. 9 , the illustrated body  114  includes an outer surface  172  that defines an outside portion of the body  114  as the body  114  bends in the horizontal plane  54  away from the outlet  106  and toward the inlet  110  (e.g., the body  114  bends toward a front of the motorcycle  10 ). The body  114  also includes an inner surface  174  that defines an inside portion of the body  114  as the body  114  bends in the horizontal plane  54 . Accordingly, the inner surface  174  generally faces toward the engine  66  and the outer surface  172  generally faces away from the engine  66 . In the illustrated embodiment, the outer surface  172  includes an apex or midpoint  178  within the horizontal plane  54  between the inlet  110  and the outlet  106 . The illustrated apex  178  is positioned at a distance  180  of less than 2.90 inches from the planar outlet flange surface  122  of the outlet  106  in a direction perpendicular to the planar outlet flange surface  122  ( FIG. 9 ). In other embodiments, the distance  180  can be less than 2.50 inches or less than 2.00 inches. For example, the distance  180  can be about 1.90 inches. Furthermore, when the conduit  90  is arranged so that the lateral plane  54  intersects both the inlet opening  146  and the outlet opening  138  ( FIG. 9 ), a third lateral dimension  181  of the body  114  is defined in the lateral plane  54 , transverse to the central axis  166  and intersects the apex  178  ( FIG. 9 ). The body  114  also includes a third height dimension  183  ( FIG. 4 ) that is transverse to the lateral plane  54  and the central axis  166  at an axial location of the third lateral dimension  181 . The third lateral dimension  181  is less than the second lateral dimension  168  and the third height dimension  183  is greater than the second height dimension  170 . 
     With reference to  FIG. 3 , the air filter subassembly  94  includes a rear end cap  182 , a velocity stack  186 , a first filter element  190 , a front end collar  194 , a second filter element  198 , and an air-impermeable cap  202 . In the illustrated embodiment, a total length  206  of the air filter subassembly  94  between the rear end cap  182  and the front end collar  194  is about 6.35 inches ( FIG. 9 ). The illustrated velocity stack  186  serves as a base or mount of the first filter element  190  for coupling the air filter subassembly  94  to the body  114 . In particular, the velocity stack  186  includes threaded velocity stack apertures  210  (e.g., four threaded velocity stack apertures  210 ). The velocity stack  186  and the rear end cap  182 —and ultimately the air filter subassembly  94 —is selectively coupled to the conduit  90  by air filter subassembly fasteners  214  (e.g., bolts;  FIG. 3 ) extending through inlet flange apertures  218  of the inlet flange  150  and rear end cap apertures  222  of the rear end cap  182  to engage the threaded velocity stack apertures  210 . As described above, the planar inlet flange surface  154  is oriented at an oblique angle relative to the vertical and horizontal planes  46 ,  54 , which also orients the velocity stack  186  at the same oblique angle relative to the vertical and horizontal planes  46 ,  54 . The velocity stack  186  also includes an ellipse-shaped groove  226  that receives an air filter subassembly gasket  230 . With reference to  FIG. 6 , the air filter subassembly gasket  230  and a portion of the velocity stack  186  extend through a central opening  234  of the rear end cap  182  so that the velocity stack  186 , the air filter subassembly gasket  230 , and the rear end cap  182  abut the inlet flange  150  of the conduit  90  to provide an air-seal between the conduit  90  and the air filter subassembly  94  (e.g., the air filter subassembly gasket  230  is compressed between the velocity stack  186  and the conduit  90  by tightening the fasteners  214 ;  FIG. 9 ). In particular, the air filter subassembly gasket  230  is compressed in an axial direction parallel to a longitudinal axis of each fastener  214 . In other embodiments, the air filter subassembly gasket  230  can be formed as a rubber overmold on at least one of the rear end cap  182  and the velocity stack  186 . In further embodiments, the rear end cap  182  and the velocity stack  186  can be formed as a single component. In some embodiments, the rear end cap  182  and/or the velocity stack  186  can be manufactured from carbon fiber, cast aluminum, or the like. 
     As best shown in  FIG. 7 , the velocity stack  186  also includes a channel  238  surrounding an interior or curved surface  242  of the velocity stack  186  that receives a rear end  246  of the first filter element  190  ( FIG. 9 ). In particular, the velocity stack  186  is fixedly coupled to the first filter element  190  so that there is no relative movement therebetween. The illustrated interior surface  242  includes an inlet end  250  and an opposing outlet end  254  with the interior surface  242  tapering from the inlet end  250  to the outlet end  254  (e.g., the inlet end  250  is larger than the outlet end  254 ). The outlet end  254  ( FIG. 6 ) is ellipse-shaped to interface with the inlet opening  146  of the conduit  90 . In other words, an interior surface of the ellipse-shaped outlet end  254  mates flush with an interior surface of the ellipse-shaped inlet  110  of the conduit  90  ( FIG. 9 ) so that there are no sharp curves or bends at the interface between the velocity stack  186  and the conduit  90 . In the illustrated embodiment, a thickness  258  of the velocity stack  186  between the inlet and outlet ends  250 ,  254  is about 0.837 inches ( FIG. 9 ). As such, a ratio of the thickness  258  of the velocity stack  186  over the total length  206  of the air filter subassembly  94  is about 0.13. 
     As best shown in  FIG. 8 , the outlet end  254  of the velocity stack  186  includes a center point  259  that is offset between opposing lateral sides  260  of the velocity stack  186 . In particular, the center point  259  is laterally spaced from the first side  260  of the velocity stack  186  (e.g., the side of the velocity stack  186  facing away from the motorcycle  10 ) at a first distance  261 , and the center point  259  is laterally spaced from the second side  260  of the velocity stack  186  (e.g., the side of the velocity stack  186  facing toward the motorcycle  10 ) at a second distance  263 . In the illustrated embodiment, the first distance  261  is smaller than the second distance  263 . 
     With reference to  FIG. 9 , the first filter element  190  tapers from the velocity stack  186  to the front end collar  194  with the front end collar  194  coupled to a front end  262  of the first filter element  190  (e.g., the rear end  246  of the first filter element  190  is larger than the front end  262 ). As described above, the velocity stack  186  is oriented at an oblique angle relative to the vertical and horizontal planes  46 ,  54 ; however, the first filter element  190  is oriented at an oblique angle relative to the velocity stack  186  so that the first filter element  190  points in a forward direction of the motorcycle  10 , i.e., a direction parallel to the vertical and horizontal planes  46 ,  54  ( FIG. 9 ). A front end  266  of the second filter element  198  is also coupled to the front end collar  194 . In contrast, the second filter element  198  tapers from the front end collar  194  to the impermeable cap  202  so that the second filter element  198  extends into the first filter element  190  toward the velocity stack  186 . As a result, the impermeable cap  202  is positioned within the first filter element  190  and is coupled to a rear end  270  of the second filter element  198  (e.g., the front end  266  of the second filter element  198  is larger than the rear end  270 ). In the illustrated embodiment, a length  274  of the second filter element  198  between the front end collar  194  and the impermeable cap  202  is about 2.63 inches ( FIG. 9 ). As such, a ratio of the length  274  of the second filter element  198  over the total length  206  of the air filter subassembly  94  is about 0.41. 
     With reference to  FIG. 2 , once the rider  62  mounts the motorcycle  10  and the rider&#39;s foot  278  is positioned on the corresponding footrest  60 , the illustrated air intake assembly  82  provides maximum clearance compared to a conventional air intake assembly (a portion of a conventional air intake assembly having a 90 degree bend is illustrated in broken lines within  FIG. 9 ) for the rider&#39;s leg  282  (e.g., the rider&#39;s knee) so that the air intake assembly  82  does not impede a comfortable riding position of the rider  62  on the motorcycle  10 . The ellipse-shaped inlet  110  allows for the outer surface  172  of the conduit  90  to be positioned closer to the engine  66  (e.g., the front cylinder block  74 ) to provide more room for the rider&#39;s leg  282  adjacent the conduit  90  than a conventional air intake assembly. For example, because the apex  178  of the outer surface  172  is positioned at the distance  180  of less than 2.90 inches from the planar outlet flange surface  122  of the outlet  106  (compared to 2.90 inches of a conventional 90 degree bend air intake assembly), the air intake assembly  82  provides more room for the rider&#39;s leg  282  and the rider  62  can sit on the motorcycle  10  more comfortably. In addition, because the center point  259  of the velocity stack  186  is offset between opposing lateral sides  260  of the velocity stack  186 , the air filter subassembly  90  can be positioned closer to the motorcycle  10  than if the center point  259  was centered between the opposing lateral sides  260 , which also increases leg room. 
     As the motorcycle  10  operates (e.g., the engine  66  is running), ambient air  286  is sucked into the air filter subassembly  94 . In particular, the ambient air  286  travels through the first filter element  190  and the second filter element  198  ( FIG. 9 ) to inhibit foreign particles (e.g., dirt and debris) from entering into the air filter subassembly  94 . Thereafter, the filtered ambient air  286  passes through the velocity stack  186  to allow for the velocity stack  186  to transform the relatively turbulent ambient air  286  into a smooth and even air flow (e.g., laminar air flow) that enters into the conduit  90 . In addition, because the velocity stack  186  mates flush with the conduit  90 , the laminar air flow is not disturbed by the interface between the air filter subassembly  94  and the conduit  90 . The laminar ambient air  286  then follows a flow path through the conduit  90  that moves substantially parallel to the central axis  166  from the inlet  110  to the outlet  106  before passing through the engine air inlet port  102  of the bracket  86  and entering the engine  66 . As described above, no portion of the central axis  166  includes a bend greater than 90 degrees, which impacts (e.g., decreases) a velocity of the airflow  286  traveling through the conduit  90  less than if the airflow  286  travels through the conventional 90 degree bend air intake assembly illustrated in  FIG. 9  (e.g., a velocity of the airflow  286  through the conduit  90  is greater than a velocity of the airflow  286  through the conventional air intake assembly). Accordingly, the combination of the velocity stack  186  and the geometry of the conduit  90  provide an increased air flow performance compared to a conventional air intake assembly without impeding a riding position of the rider  62  on the motorcycle  10 . 
     Various features and advantages of the disclosure are set forth in the following claims.