Abstract:
A combined air cleaning and flow rate sensing system for the combustion air of an internal combustion engine is disclosed. The system includes a housing providing an inlet and a filter at least partially disposed in the housing. The air cleaner system also includes a conduit adjacent the housing and providing a flange and an outlet. The air cleaner system also includes a compressible seal disposed between the filter and the flange. The air cleaner system also includes a locking mechanism adapted to selectively secure the conduit to the housing such that the seal may be compressed between the conduit and the filter. The air cleaner system also includes an accessory mounted to the conduit. The air entering the inlet exits through the outlet.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to air induction systems for the combustion air of internal combustion engines. In particular, the present invention relates to air induction systems providing an integral mass airflow sensor, to measure the amount of air flowing through an air cleaner system. 
     BACKGROUND OF THE INVENTION 
     It is well known to provide an air cleaner for purifying raw air before mixing the raw air with fuel for combustion in an internal combustion engine. Such known air cleaners are typically used in automobiles. In operation, such known air cleaners provide for the intake of raw air, the purification of the raw air and the routing of the purified air to a cylinder of an internal combustion engine. In fuel injected engines, this flow rate of combustion air is monitored by a mass airflow sensor disposed someplace in the combustion airflow path. These mass airflow sensors are typically calibrated before installation and are inserted into tubes, housings or conduits that communicate with the combustion airflow path. One problem with these sensors is that they are quite sensitive to alignment and orientation. Furthermore, they are easily damaged during replacement and testing. It would be beneficial, therefore, to provide a mass airflow sensor that is coupled to a readily removable conduit that will protect the sensor elements and also more readily permit sensor testing. Since air cleaners are often provided with readily removable conduits to permit the replacement of air filter elements, it would also be advantageous to dispose of the mass airflow sensor in such a conduit associated with the air cleaner. 
     SUMMARY OF THE PRESENT INVENTION 
     The air cleaner and mass airflow rate sensing system includes a housing providing an inlet and a filter at least partially disposed in the housing. The system also includes a conduit adjacent the housing and providing a flange and an outlet. The system also includes a compressible seal disposed between the filter and the flange. The system also includes a locking mechanism adapted to selectively secure the conduit to the housing such that the seal may be compressed between the conduit and the filter. The system also includes mass airflow sensor mounted to the conduit. 
     The present invention further relates to an air induction and mass airflow rate sensing assembly at least partially disposed in a housing of an air cleaner system for purifying air. The housing provides an inlet and the air cleaner system provides a filter at least partially disposed within the housing, a compressible seal and a locking mechanism. The air induction assembly includes a conduit having a first end and adapted for placement at least partially within the housing and the filter such that a second end extends at least partially from the housing. The air induction assembly also includes a flange extending about the circumference of the conduit. The air induction assembly also includes a mass airflow sensor mounted to the conduit. The seal is disposed between the filter and the flange and the locking mechanism is configured to selectively secure the conduit to the housing. 
     The present invention further relates to an air cleaning and flow rate measuring system. The system includes a filter element for filtering air. The air cleaner system also includes a housing for supporting the filter element and surrounding the filter element. The system also includes an inlet for introducing air into the housing and into the filter element. The system also includes a conduit providing a flange and an outlet and being disposed adjacent to the filter element. The system also includes a seal for inhibiting the leakage of air from the filter element and disposed between the filter element and the housing. The system also includes a locking means for securing the conduit to the seal and to the housing. The system also includes a mass airflow rate sensor mounted to the conduit. Air enters the housing through the inlet, the air is purified by the filter element, and the air exits the housing through the outlet. 
     It is an object of this invention to provide an air induction assembly that is capable of rapid replacement. It is also an object of this invention to provide a sensor assembly that is easily accessible and capable of rapid testing or calibration. It is a further object of this invention to provide a sensor that readily interfaces with an air filter. Other objects, features and advantages of the invention will become apparent to those skilled in the art upon review of the following FIGURES, the detailed description and the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partially fragmentary exploded perspective view of an air cleaner system in accordance with a preferred embodiment of the present invention; 
     FIG. 2 is a fragmentary exploded perspective view of the air cleaner system of FIG. 1; 
     FIG. 3 is a perspective view of an air induction system according to a preferred embodiment of the present invention; 
     FIG. 4 is a top plan view of the air induction system of FIG. 3; and 
     FIG. 5 is a side elevation view of the air induction system of FIG.  3 . 
    
    
     Before explaining in detail at least one preferred embodiment of the invention, it is to be understood that the subject matter recited in the claims is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or shown in the FIGURES. The subject matter recited in the claims is capable of other embodiments or being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1, an air cleaner system  10  for purifying raw air is shown according to a preferred embodiment of the present invention. System  10  includes an air induction assembly  60  coupled to a replaceable filter assembly  140 , which is contained within a housing  12 . In the operation of system  10 , raw air is drawn from the exterior of housing  12  into a conduit (shown as a snorkel  18 ). The raw air is directed through filter assembly  140 , is purified, and the resulting purified air is directed to an outlet  66  of air induction assembly  60 . An arrow  188  shows the general directional flow of the air through air cleaner system  10 . 
     Referring to FIG. 3, air induction assembly  60  is shown according to a preferred embodiment of the present invention. Air induction assembly  60  defines an airflow path for the purified air as indicated by arrow  188 . Air induction assembly  60  includes a conduit (shown as tube  62 ) having an inlet  64  and outlet  66 . Inlet  64  of tube  62  is positioned within the interior of housing  12 . Outlet  66  of tube  62  extends from the exterior of housing  12 . A fastener (shown as a capture clamp  162 ) secures a conduit (shown as a hose  160 ) to outlet  66  of tube  62 . Hose  160  has an interior diameter  186  greater than an exterior diameter  180  of outlet  66 . Hose  160  directs the purified air from outlet  66  to other engine systems (not shown) for processing (e.g., to a carburetor for the mixing of the purified air with fuel, and the eventual placement of the resulting mixture in the cylinder of an internal combustion engine). 
     Referring to FIGS. 3 through 5, a mass airflow rate sensor assembly (shown as assembly  100 ) is mounted to the exterior of tube  62 . Assembly  100  is positioned between an inward ridge  82  and an outward ridge  80  of tube  62 . Assembly  100  includes an upper housing  112  secured to a lower housing  114  that encapsulate a mass airflow rate sensor  116  and a temperature sensor  118 . Upper housing  112  and lower housing  114  may serve to protect sensor  116  and temperature sensor  118  from environmental factors (e.g., debris, water, heat, vibration, physical manipulation, damage during shipping, etc.). A detector (not shown) capable of monitoring environmental variables (e.g., combustion air speed, air temperature, air density, air moisture, etc.) extends from lower housing  114  into the interior of tube  62 . An electrical conductor (shown as a wire  120 ) connects assembly  100  to an engine system (not shown) such as a computer. According to any preferred or alternative embodiments as shown in FIGS. 1 through 3, assembly  100  may be integrally mounted to tube  62  and may be provided as a complete unit pre-calibrated to known variables related to tube  62  (such as engine size, air temperature, the geometry of tube  62 , the distance between the periphery of tube  62  and the detector, etc.). 
     Referring to FIG. 2, a generally circular-shaped air filter element (shown as a canister  142 ) of filter assembly  140  is positioned within the interior of housing  12  and supported by a cradle  26 . Canister  142  includes an air receiving surface (shown as an outer wall  150 ) and an air emitting surface (shown as an inner wall  152 ). In the operation of system  10 , raw air enters canister  142  through outer wall  150  and is directed through a filter media  156  (such as pretreated, pleated corrugated paper). During the purification of the raw air, impurities (e.g., debris, particulates, gasses, dirt, pollution, etc.) may be entrapped in filter media  156 . The purified air exits filter media  156  through inner wall  152  of canister  142 . A covering (shown as an end cap  148 ) circumscribes and surrounds the bottom of canister  142 . End cap  148  promotes the entry of raw air through outer wall  150  by covering or blocking the lower portion of canister  142 . Filter assembly  140  also includes a generally “V”-shaped flexible, compressible seal  154  mounted to the upper portion canister  142 . Seal  154  extends radially around an aperture  158  of canister  142 . A fastener (not shown), such as an adhesive or glue, may secure seal  154  to canister  142 , and may secure a left end  144  of filter media  156  to a right end  134  of filter media  156 . Alternatively, seal  154  may be integrally molded to canister  142 . 
     When system  10  is in a fully assembled condition (as shown in FIG.  1 ), canister  142  is positioned within housing  12 , and inlet  64  of tube  62  is positioned within canister  142 . An outer diameter  190  of inlet  64  is less than a diameter  182  of an aperture  158  of canister  142 . A diameter  184  of an aperture  52  of an upper shell  14  of housing  12  is greater than an outer diameter  192  of end cap  148 , and outer diameter  190  of inlet  64  is less than diameter  182  of aperture  158  of canister  142 . (See FIG. 2.) 
     A flange  68  integrally mounted to tube  62  extends about the periphery of tube  62 . A housing connector system  40  of upper shell  14  secures filter assembly  140  to a conduit connector system  70  of flange  68 . Housing connector system  40  and conduit connector system  70  may serve to compress seal  154  and form a closure or connection between filter assembly  140  and air induction assembly  60  such that air is inhibited from bypassing canister  142 . Housing connector system  40  includes outwardly extending protrusions (shown as fingers  42 ) and inwardly extending indentations (shown as fingers  44 ) spaced generally evenly about the periphery of aperture  52  of upper shell  14 . Conduit connector system  70  includes reciprocal outwardly extending protrusions (shown as fingers  72 ) and inwardly extending indentations (shown as fingers  74 ) spaced generally evenly about the periphery of flange  68  of tube  62 . Conduit connector system  70  also includes a cover  76  positioned over fingers  74  (see FIG.  4 ). To create the effective closure or connection between filter assembly  140  and air induction assembly  60 , a compressive force is applied to air induction assembly  60  to compress seal  154  between a seal engaging surface  78  of flange  68  and canister  142 . Fingers  72  of conduit connector system  70  are aligned with and inserted into fingers  44  of housing connector system  40 . Tube  62  is rotated relative to upper shell  14  (or vice versa) such that fingers  72  of conduit connector system  70  are positioned below fingers  42  of housing connector system  40  (i.e., the fingers of the housing connector system and the conduit connector system are rotated until they are intertwined and interconnected) and cover  76  is positioned over fingers  44  of housing connector system  40 . The compression of seal  154  and the interconnection of the fingers  42  and fingers  72  maintain such compressive force. 
     A locking system  90  inhibits further rotation of tube  62  relative to upper shell  14  (such rotation may cause a disconnection between fingers  42  of housing connector system  40  and fingers  72  of conduit connector system  70 ). Locking system  90  includes a ramp  46  mounted to the exterior of upper shell  14  and positioned adjacent to the periphery of aperture  52 . Ramp  46  includes an inclined surface  48  and a vertical surface  50 , which is orthogonal to fingers  42  of upper shell  14 . To secure locking system  90  in a closed position, tube  62  is rotated relative to upper shell  14  (or vice versa) such that a glide  92  mounted to flange  68  slides over inclined surface  48  of ramp  46 . Tube  62  is rotated until a catch  94  of glide  92  passes beyond vertical surface  50  of ramp  46 . Further rotation of glide  92  is inhibited by a vertically extending protrusion (shown as a stop  54 ), which is positioned orthogonal to fingers  42  of shell  14 . Thus, when locking system  90  is in the closed position, glide  92  is secured between vertical surface  50  of ramp  46  and stop  54 . To release locking system  90  from the closed position to an opened position, a force is exerted on a stem  96  of glide  92  to lift stem  96  above both vertical surface  50  and stop  54  such that tube  62  may be further rotated. Upon such further rotation of tube  62 , fingers  42  of housing connector system  40  and fingers  72  of conduit connector system  70  become nonaligned and disconnected such that the closure or seal between seal engaging surface  78  of flange  68  and canister  142  is broken. According to an alternative embodiment as shown in FIGS. 3 and 4, locking system  90  may include reinforcing tabs  98  to secure flange  68  to glide  92 . 
     Referring to FIG. 2, housing  12  includes upper shell  14  mounted to a lower shell  16 . Upper shell  14  includes a cavity (shown as a reservoir  194 ) and aperture  52  for receiving filter assembly  140  in reservoir  194 . A downward sealing surface  20  engages an upward sealing surface  22  of lower shell  16 . Lower shell  16  includes a cavity (shown as a reservoir  196 ) for the housing or encapsulation of filter assembly  140 . A support structure (shown as cradle  26 ) provides support to canister  142 . Cradle  26  includes a radial support (shown as a flange  28 ) and a transverse support (shown as a flange  30 ). A generally “U”-shaped indent  32  of flange  30  provides a surface upon which outer wall  150  of canister  142  may rest. A generally “V”-shaped indent  38  of flange  28  (having a bottom leg  34  and a side leg  36 ) provides a surface upon which the lower portion of canister  142  may rest, such that bottom leg  34  supports end cap  148  of canister  142  and side leg  36  supports outer wall  150  of canister  142 . According to other alternative embodiments as shown in FIGS. 1 and 2, upper shell  14  may include apertures (not shown), which provide a convenient mounting point for mounting elements such as an air or fluid shock mounting (shown as a grommet  164 ). According to any preferred or alternative embodiment, the exterior of the upper shell may include surface textures to provide additional support to the housing and to assist in the channeling of elements (e.g., air, water, debris, etc.) across the housing. 
     According to a particularly preferred embodiment, the air cleaner system is used to purify raw air before the raw air is routed to an automotive or vehicular engine. The upper shell and the lower shell of the air cleaner system are preferably constructed of plastic that are vibration welded together at about 120 hertz. The hose mounted to the air induction assembly is preferably made of polyvinylchloride (PVC). The filter element is preferably constructed of paper folded in a zigzag configuration. The end cap is preferably constructed of aluminum metal and encapsulated in urethane. The seal is preferably generally “V”-shaped and constructed of urethane rubber. The accessory is preferably a mass airflow sensor, which measures the amount of raw air purified by the air cleaner, that is pre-calibrated to the geometry of the air induction assembly (e.g., by running a known airflow through the conduit and accounting for various environmental factors such as air speed, air temperature, the diameter of the conduit, the type of engine associated with the air induction assembly, etc.). 
     It should be noted that the use of the term “conduit” is not meant as a term of limitation, insofar as any valve, hose, tube or like structure providing a channel or passageway through which air may flow is intended to be included in the term. It should also be noted that the use of the term “directed” is not meant as a term of limitation, insofar as any routing or leading of raw or purified air into, through and out of the air cleaner system is intended to be included in the term. It should also be noted that the use of the term “engine system” is not meant as a term of limitation, insofar as any “engine” or like machine for using fuel to produce motion or accompanying accessory (e.g., catalytic convert, carburetor, cylinder, fuel injection system, computer system, fan, etc.) is intended to be included in the term. 
     While a preferred embodiment of the invention is as described above, there are several substitutions that may be made without departing from the beneficial features of the above-described invention such as variations in sizes, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, or use of materials. For example, the mounting of the upper shell and the lower shell of the housing may be replaced with such well known substitutions as an interlocking tab and slot arrangement (which would have the added benefit of permitting the upper shell to be removed entirely from the lower shell), the hinging of the upper shell to the lower shell (which would permit the shells to be pivotally opened and closed), or other suitable fastening devices (such as welding, ultrasonic welding, vibration welding, glue, screws, rivets, clamps or other conventional methods) or the housing may be provided as a single piece. The aperture in the upper shell may be provided in either or both of the shells. 
     According to other alternative embodiments associated with the filter assembly, the filter element may be disposable. The filter material may be constructed of a porous material (e.g., cardboard, corrugated paper, carbon block, etc.) or a natural or synthetic fibrous material (e.g., spun polyethylene, glass wool, microbial filter, etc.). The effective closure or seal between the air induction assembly and the housing may be formed by any known connection system (such as a bayonet connector system, a threaded connection, a clamp, etc.) and may be maintained by any locking mechanism (e.g., a detent, a tumbler lock, a tacky adhesive, etc.). The seal may be mounted to the upper shell, fixed to a rigid or semi-rigid framework that also extends about the periphery of the filter element, or detached from both the upper shell and the filter element. The seal may be positioned between the filter and the air induction assembly or between the air induction assembly and the housing. The inlet of the air induction assembly may be positioned in close proximity to the filter element or a space may be provided between the inlet of the air induction assembly and the filter element. Likewise, the filter element may be positioned in close proximity to the periphery of the aperture of the upper shell or a space may be provided between the filter element and the periphery of the aperture of the upper shell. The base of the lower shell may support the bottom portion of the filter element. 
     According to other alternative embodiments associated with the air induction assembly, the air induction assembly may be disposable or selectively removable from the filter assembly. A screen of geometric cells (e.g., hexagonal cells) may cover the conduit or a flow straighter may be provided within the conduit to inhibit the formation of undesirable airflow (e.g., eddies) around the detector. A vapor management valve may be provided in the flow path of the air induction assembly. The accessory may be permanently or removably mounted to the air induction assembly. Such mounting of the accessory may be integral (such as by the use of potting compounds or adhesives) or removable (such as by known fastening devices). The accessory and the detector may be mounted at any position on the conduit or may be positioned either upstream or downstream from the airflow path through the conduit. 
     Thus, it should be apparent that there has been provided in accordance with the present invention an air cleaner system that fully satisfies the objectives and advantages set forth above. Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the invention is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the preferred embodiments without departing from the spirit of the invention as expressed in the appended claims.