Abstract:
The present invention generally relates to snowmobiles. More particularly, the present invention relates to the components of a snowmobile such as the frame, running boards and various other assemblies.

Description:
[0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/302,394, filed on Feb. 8, 2010, and U.S. Provisional Patent Application Ser. No. 61/337,676, filed on Feb. 9, 2010, the complete disclosures of which are expressly incorporated by reference herein. 
     
    
     BACKGROUND 
       [0002]    The present invention generally relates to snowmobiles. More particularly, the present invention relates to the components of a snowmobile such as the frame, suspension, running boards and various other assemblies. 
         [0003]    Generally, there are a variety of configurations of snowmobiles available for applications such as deep snow, high performance, luxury touring, trail riding, etc. Most snowmobiles include a frame, a power train, a pair of front skis, and an endless belt assembly. Typically, features such as engine displacement and track length vary depending upon the specific application for which the snowmobile is targeted. For example, snowmobiles designed primarily for deep snow application may include an endless belt assembly having a longer track length, i.e. 166 inches (4.2 meters), than a snowmobile designed primarily for trail riding, i.e. 135 inches (3.4 meters). A snowmobile designed for deep snow may also include a relatively large displacement engine, i.e. 900 cc 3  (54.9 inches 3 ), to provide suitable power when operating in a mountain environment at higher elevations with less oxygen. Other features of a deep snow snowmobile may be added to improve ride and handling characteristics such as side hilling. 
         [0004]    A deep snow snowmobile is shown in our patent application Ser. No. 11/501,454 filed Aug. 9, 2006, the contents of which are incorporated herein by reference. 
       SUMMARY 
       [0005]    One illustrative embodiment of the present invention includes a snowmobile comprising a frame, a power train supported by the frame; a running board assembly supported by the frame and comprising a toe clip, a front wall and a foot tread; and a shroud laterally encompassing the toe clip and the back wall, with the toe clip extending rearwardly, beyond a rear edge of the shroud. 
         [0006]    Another illustrative embodiment of the present invention includes a frame; a power train supported by the frame; a running board assembly supported by the frame and comprising a toe clip, a front wall and a foot tread; and a shroud laterally encompassing the toe clip and the back wall, with the back wall extending substantially aligned with a rear edge of the shroud. 
         [0007]    Another illustrative embodiment of the present invention includes a snowmobile comprising: a frame; a power train supported by the frame; and a running board assembly supported by the frame and comprising a toe clip, a front wall and a foot tread; the foot tread having upturned embossed openings having gripping surfaces thereon. 
         [0008]    Another illustrative embodiment of the present invention includes a snowmobile comprising a frame; a power train supported by the frame; and a running board assembly supported by the frame and comprising a toe clip, a front wall and a foot tread; the foot tread having upturned embossed openings and openings through the running board. 
         [0009]    Another illustrative embodiment of the present invention includes a snowmobile comprising a frame; a power train supported by the frame; a running board assembly supported by the frame and comprising a toe clip, a front wall and a foot tread; and a shroud laterally encompassing the toe clip and the back wall, with the back wall extending substantially aligned with a rear edge of the shroud. 
         [0010]    The above mentioned and other features of this invention, and the manner of attaining them, will become more apparent and the invention itself will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a front perspective view of an illustrative embodiment of a snowmobile; 
           [0012]      FIG. 2  is a rear perspective view of the embodiment shown in  FIG. 1 ; 
           [0013]      FIG. 3  is a side view of the left hand side of the embodiment shown in  FIG. 1 ; 
           [0014]      FIG. 4  is a side view of the right side of the embodiment shown in  FIG. 1 ; 
           [0015]      FIG. 5  is a top view of the embodiment shown in  FIG. 1 ; 
           [0016]      FIG. 6  is a front view of the embodiment shown in  FIG. 1 ; 
           [0017]      FIG. 7  is a rear view of the embodiment shown in  FIG. 1 ; 
           [0018]      FIG. 8  is a bottom view of the embodiment shown in  FIG. 1 ; 
           [0019]      FIG. 9  is an enlarged view of the running board assembly of the embodiment shown in  FIG. 1 ; 
           [0020]      FIG. 10  is an enlarged view of the foot tread of the embodiment shown in  FIG. 1 ; 
           [0021]      FIG. 11  is an enlarged side view of a front portion of the running board; 
           [0022]      FIG. 12  is an exploded view of the tunnel; 
           [0023]      FIG. 13  is an enlarged view of the rear snow flap; 
           [0024]      FIG. 14  is a partial front perspective view of the snowmobile with the front body removed; 
           [0025]      FIG. 15  is an enlarged front perspective of the front frame; 
           [0026]      FIG. 16  is a front perspective of the cast frame member; 
           [0027]      FIG. 17  is an underside perspective view of the cast frame member of  FIG. 16 ; 
           [0028]      FIG. 18  is a rear view of the cast frame member; 
           [0029]      FIG. 19  is a front perspective view of the steering assembly; 
           [0030]      FIG. 20  is a side view of the steering assembly mounted to the cast frame member of  FIG. 16 ; 
           [0031]      FIG. 21  is a side perspective view of a heat shield member mounted to an inside of the body panel; and 
           [0032]      FIG. 22  is an exploded perspective view of the air intake system; 
           [0033]      FIG. 23  is a side showing the suspension system removed from the tunnel; and 
           [0034]      FIG. 24  shows an exploded view of a rear bumper. 
       
    
    
     DETAILED DESCRIPTION 
       [0035]    Corresponding reference characters indicate corresponding parts throughout the several views. Although the drawings represent embodiments of the present invention, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate and explain the present invention. 
         [0036]    The embodiments disclosed below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may utilize their teachings. For example, while the following description refers primarily to a snowmobile, it should be understood that the principles of the invention apply equally to other snow vehicles. While the present invention primarily involves a snowmobile, it should be understood, however, that the invention may have application to other types of vehicles, such as motorcycles, ATVs, utility vehicles, scooters, and mopeds. 
         [0037]    Referring to  FIGS. 1-8 , one illustrative embodiment of a snowmobile  10  is shown. Snowmobile  10  includes a frame  12 , supported by front skis  14  and by endless belt assembly  16 . Front skis are coupled to a front suspension  18 , and endless belt assembly is supported by a rear suspension  20 . Snowmobile also includes a seat assembly  22 , front outer body  24 , and a steering assembly  26 . Steering assembly  26  is operably coupled to steering arms  28  ( FIG. 2 ) which allows a rider to steer snowmobile  10 . A power train is covered by outer body  24  and provides power to endless belt assembly  16 . Running board assemblies  32  extend along the sides of the seat assembly which are supported by the frame  12 . A snow flap  34  ( FIG. 2 ) is also supported by the frame rearward of the endless belt. 
         [0038]    With reference to  FIGS. 1 and 2 , frame  12  includes a tunnel  40  having a top wall  42  and side walls  44 . As shown best in  FIG. 2 , endless belt  16  at least partially runs up into tunnel  40  between side walls  44  and upwardly towards top wall  42 . As shown, running board assemblies  32  include a rider&#39;s foot grip assembly  50  ( FIG. 4 ) and a foot tread assembly  52 , where the foot grip assembly  50  and foot tread assembly  52  are supported by the tunnel sidewall  44 . As shown best in  FIGS. 11 and 12 , the tunnel  40  also include a plurality of cutout portions  46  which reduce the material in locations where fasteners are not needed. These cutouts  46  help to reduce the weight of the entire vehicle. The surface to which sidewalls  44  abut (not shown), also include notches but complement notches  46  such that the notches do not overlap. Other cutouts could be provided elsewhere as well. 
         [0039]    With reference now to  FIG. 9 , the foot grip assembly  50  is shown in greater detail. Foot grip assembly  50  includes frame member  100  which extends over the top wall  42  of tunnel  40 , having a first portion  102  extending downwardly and away from the tunnel, and a second portion  104  extending downwardly and reversely bent towards the tunnel. The end of portion  104  is flattened and includes a flange at  106 . Foot grip assembly  50  further includes a tube portion  110  which is fastened to the side of the tunnel and connected to frame portion  100  for example, by welding. A toe clip  112  extends between frame member  110  and frame portion  102 . Finally, foot grip assembly  50  includes a back wall  114  attached at marginal edges  115  and  116 , and comprises plural slotted openings  118 . 
         [0040]    With reference to  FIGS. 9-12 , foot tread assembly  52  is comprised of an elongate frame member  122  and running board plate  124 . Elongate frame member  122  is comprised of a tube  126  and a frame bracket  128 . As shown in  FIG. 12 , frame bracket  128  is discreet from tube  126 . Bracket  128  includes a bracket foot  130  which extends into tube  126  and a bracket arm  132  for attachment to flange  106 . Bracket foot  130  may be attached to tube  126  by way of fasteners, welding or adhesives, or a combination thereof. As shown ( FIG. 9 ), the flattened surfaces of flanges  106  and bracket arms  132  are positioned back to back and attached by way of fasteners  134  ( FIG. 9 ). Furthermore, the planes of the flat surfaces of flanges  106  and bracket member  132  extend in a longitudinal direction as described herein. 
         [0041]    With respect now to  FIGS. 9 and 10 , running board plate  124  is comprised of a plate portion  140  having a lip  142  positioned and attached to elongate tube member  126  as shown. The opposite side of the plate portion  140  has a marginal edge  144  which is attached to the tunnel side wall  44 . As shown in  FIG. 12 , the running board plate  124  is integral with the tunnel side wall  44 , however this connection could also be by fastening, such as by welding, adhesives or riveting. 
         [0042]    The running board plate  124  further includes a plurality of upturned embossments  150  ( FIG. 10 ) having a generally triangular shape with gripping serrations  152  positioned thereon. Intermediate each of the upturned embossments  150  is an opening  156 , of reverse triangular shape, where the embossments  150  rigidify the plate portion  140  whereas openings  156  maximize the open area of the foot tread to allow snow to drop downwardly therethrough. This provides a smooth bottom surface to plate portion  140 , having no interference with the snow. 
         [0043]    Thus, as shown in  FIG. 9 , an enlarged ventilation area is defined by the spacing at  160  and within the slots  118 . The longitudinal disposition of the flanges  106  and  132  as described above also maximizes the ventilation area  160 , particularly for the removal heat from the engine compartment as described herein. 
         [0044]    Finally, with respect to  FIGS. 9-11 , an outer shroud  180  covers foot grip assembly  50  and includes a shroud portion  182  which encompasses portions  102  and  104  of frame tube  100 . Shroud  180  also includes a rear edge  184  ( FIG. 11 ) which is proximate to back wall  162 . As shown best in  FIG. 11 , toe clip  112  extends rearwardly beyond rear edge  184  of shroud  180  which provides easy access for the rider to place their boot in the toe clip, yet prevents forming a pocket into which snow may accumulate and pack. Also, the forward angle of edge  184  allows a rider&#39;s foot to position sideways, overlapping the foot tread assembly  52 , and yet stay retained behind foot grip assembly  50 . 
         [0045]    With reference now to  FIG. 13 , snow flap  34  is shown in an enlarged view. Snow flap  34  is hingedly mounted to the tunnel  40  along a rear edge  190 . The snow flap  34  includes a plurality of apertures  192  which reduces the overall weight of the component. These could be machined or molded in. 
         [0046]    With reference now to  FIG. 14 , the outer body  24  has been removed which better exposes the engine compartment  200 , the steering assembly  26 , the frame front portion  202 , and the power train  204 . The power train  204  includes an engine  206  having an exhaust system  208 , an intake system  210  and a drive system including a CVT  212 . As mentioned above, the ventilation area  160  was defined around the foot grip area, and this allows the CVT ventilation to exhaust through ventilation area  160 . 
         [0047]    With reference now to  FIG. 15 , the front portion  202  of the frame is shown in greater detail. Front portion  202  includes a cast coupling or connector  220  configured to attach plural frame tubes, namely front frame tubes  222 ,  224  and rear frame tubes  226  and  228  thereto. The frame tubes  222 ,  224 ,  226 ,  228  may be attached to the cast coupling  220  by way of fasteners such as  230  and/or may be adhesively fixed to the cast coupling  220 . As shown, the cast coupling  220  further includes two support webs  232  and  234 . Each of the webs is provided with threaded apertures, for example,  236  and  238 . As also shown in  FIG. 15 , a steering post  260  of steering assembly  26  is directly coupled to webs  232  and  234  of the cast coupling  220 , as described herein. 
         [0048]    With reference now to  FIGS. 16-18 , cast coupling  220  will be described in greater detail. Cast coupling  220  further includes a first circular channel ( FIG. 16 ) defined by portions  240  and  242  having threaded bosses  244  extending downwardly therethrough. A second circular channel is defined by portions  246  and  248  having threaded bosses  250  therein. The circular channels are intersected by cylindrical members  252  and  254 . Thus, with a comparison of  FIGS. 15 and 16 , it should be appreciated that frame tubes  222  and  224  are positioned across the circular channels with fasteners such as  230  positioned through the frame tubes  222 ,  224  and into the threaded bosses  244 ,  250 . Adhesive may also be applied. Meanwhile, frame tubes  226  and  228  are positioned in the cylindrical members  252  and  254 , and may also be fixed in place by way of fasteners and adhesive. 
         [0049]    With reference now to  FIG. 18 , cast coupling  220  includes machined mounting surfaces  232 A and  234 A on the backside of the webs  232  and  234 , respectively, for mounting the steering post as described below. Finally as best shown in  FIG. 17 , cast coupling  220  includes an integral fuel tank mounting tab shown at  258 . 
         [0050]    With reference now to  FIG. 19 , the steering assembly is shown in greater detail. As shown, steering post  260  includes an upper and lower bearing posts  270  and  272  which attach to the backside of the webs  232 ,  234  respectively, with fasteners being attached to threaded apertures  236  and  238 , respectively. This rigidly connects the steering post  260  to the cast coupling  220  yet allows the steering post to pivot about the corresponding bushings  270  and  272 . As also shown, handlebars  276  of steering assembly  26  are attached to the steering post  260  by way of a clamp at  278 . 
         [0051]    Steering assembly  26  further comprises a lower steering post  280  which is operatively coupled to steering post  260  by way of respective link arms  282 ,  284 , connected together by way of a link  286 . Lower steering post  280  is ultimately connected to steering arms  28  by way of a further steering arm, not shown, to maneuver the steering skis  14 . 
         [0052]    With reference now to  FIG. 20 , steering assembly  26  is shown mounted to the backside of cast coupling  220  with the bushings  270 ,  272  ( FIG. 19 ) mounted to the surfaces  232 A,  234 A ( FIG. 18 ), respectively. As shown, steering post  260  is nearly vertical and could be in the range where angle θ could be between 0 and 15 degrees and as shown is about 13 degrees. As steering post  260  is positioned at a substantially upright angle, the ergonomics is improved for the deep snow rider. 
         [0053]    As known, when side hilling, a rider is often standing on only one side of the running board assemblies  32  and the maneuverability of the steering post and handlebars  276  is substantially increased when the steering post  260  is close to vertical. This prevents the handlebars  276  from dipping down or raising up on either side when attempting to steer the snowmobile while standing on only one side. 
         [0054]      FIG. 20  also shows a fuel tank  258  having a front end positioned adjacent to the integral fuel tank mounting tab  256  to retain a front end of the fuel tank  258 . Fuel tank  258  may be attached to tab  256  through fasteners, or fuel tank could have a molded slot to be applied over tab  256 . 
         [0055]    With respect now to  FIG. 21 , front side panel  300  (see also  FIG. 4 ) on the right hand side of the snowmobile is provided with sound insulation  302  as well as a heat shield  304 . The foam includes a front surface  306 , a back surface  308 , and a plurality of cutouts  310  extending between the front and back surface. Heat shield  304  includes a plate  320  having a plurality of mounting feet  322  which correspond in location to the apertures  310 . An adhesive is provided against the back surface  308  to retain sound insulation to the inside surface of the panel  300 . Heat shield  304  can be placed with the feet  322  aligned with the associated apertures  310  and pressed against the foam  302  until the feet contact the adhesive, through the apertures, which retains the heat shield to the foam member  302 . This prevents any fasteners or additional dimensional requirements for attaching the heat shield to the foam. This also provides less weight for the snowmobile yet provides a heat shield  304  adjacent to a portion of the exhaust system of the snowmobile power train as described above. The adhesive could be a double-sided sticky tape, double sided foam tape, or any other adhesive for the purposed described. 
         [0056]    Referring now to  FIG. 22 , air inlet  210  ( FIG. 15 ) is shown in greater detail as comprised of inlet housing  350 , retainer housing  352  and sound-deadening foam  354 . Housing  350  is generally rectangular having a plurality of apertures  356  extending therethrough, where the rectangular housing has a front wall  360 , sidewall  362  opposite side wall  366  and rear wall  368 . Retainer  352  includes a front wall  370 , sidewall  372  having lugs  374 , opposite sidewall  376  and a partial rear wall  378 . Sound-deadening foam  354  generally includes a foam body portion  380  having locating apertures at  382 . 
         [0057]    It should be appreciated that the foam  354  is positioned on an inside of the retainer member  352  with lugs  374  aligned with apertures  382  of the foam  354 . The retainer and foam together are then snapped around housing  350  with the front wall  370  of retainer  352  positioned against front wall  360  of housing  350 , sidewalls  372  and  376  positioned adjacent to corresponding sidewalls  362  and  366 , respectively, and with partial wall  378  at retainer  352  positioned against back wall  368 . The retainer  352  and housing  350  can be held together by way of corresponding latch members such as lug  390  and aperture  392  to retain the two components together. This provides an easy to assemble two component intake system  210  having an internal housing  350  and a retainer housing  352  whereby air traveling through the intake system can be sound-deadened by foam member  354 . 
         [0058]    With reference now to  FIG. 23 , rear suspension  20  is shown removed from the tunnel, understanding that the rear suspension is attached to the underside of tunnel  40 . Suspension  20  includes a frame  400  having laterally spaced frame rails  402  with slide rails  404  attached thereto. Suspension  20  includes two coil over shocks  406  and  408  providing dampening between the tunnel  40  and frame  400 . A track roller  410  is mounted on the outside of the slide rail  402 , and as shown, has an outer radial surface  412  which extends beyond lower surface  414  of slider  404 . Track rollers  410  are located at a position proximate a maximum pressure point between the sliders  404  and track (absent the track wheel) which allows the track a slight spacing between the sliders  404  preventing substantial frictional heating. Suspension  20  also includes idler rollers  420  and  422 . Scratchers  426  are also provided on the side of frame  404  to break up crusted snow in order that the track can throw snow against the underside of tunnel  40 , as the tunnel includes a heat exchanger for engine water. 
         [0059]    With reference now to  FIGS. 13 and 24 , a rear bumper assembly  450  is shown including a rear bumper member  452  and side brackets  454 . Bumper member  452  is comprised of a carbon fiber material and as best shown in  FIG. 24  has an outer diameter  456 , an inner diameter  458 , and apertures  460 . Side brackets  454  are comprised of an extruded aluminum and include apertures  462  for mounting the side brackets to tunnel  40  by way of fasteners  464  ( FIG. 13 ). As shown, extruded brackets  454  have extruded openings at  466  and apertures  468  which extend into openings  466 . A cap  470  is also provided having a lip  472 , and a reduced diameter portion  474  having apertures  476 . 
         [0060]    To assemble bumper assembly  450 , bumper member  452  is positioned in openings  466  of extruded members  454 . Caps  470  are positioned with diameter portions  474  within inner diameter  458  and with the lips  472  against the extruded side bracket  454 , with apertures  460  and  476  aligned. Fasteners  480  are then placed through the extruded members  454 , bumper member  452  and cap  470  to retain the bumper member thereto. Fasteners  464  could be set screws, bolts, rivets or any similar fastening device, although as shown, fasteners  480  are rivets. As also shown in  FIG. 13 , snow flap  34  includes a stop member  490  integrally molded with the flap which has an upper stop surface  492  which abuts against the bumper member  452 . 
         [0061]    It should be generally understood that the description provided herein relates only to the specific embodiment, and that other variations could be envisions. For example, while referring herein to tubes, cylindrical tubes are shown, but it is contemplated that other structural geometries, such rectangular or square tubes could also be used. 
         [0062]    While this invention has been described as having an exemplary design, the present invention may be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.