Abstract:
A snowmobile having a hood releasably secured to the snowmobile via interlocking male-female members, the hood being manually releasable from the snowmobile without the use of tools. A snowmobile having a hood releasably secured to the snowmobile via a hook and elastic connector, and having fairings with a moveable section constructed and arranged to conceal or cover the hook and elastic connector.

Description:
This application claims priority to U.S. provisional application Ser. No. 60/738,979, filed Nov. 23, 2005, which is incorporated herein by reference. 

   FIELD OF THE INVENTION 
   The present invention relates to snowmobiles, and more particularly, snowmobile hood attachment systems. 
   BACKGROUND OF THE INVENTION 
   Conventional snowmobiles have a set of fairings at the front thereof surrounding the engine. While different snowmobiles may have different reasons for employing such fairings, some typically are improving the aerodynamics of the snowmobile, improving the aesthetics of the snowmobile, protecting the engine and surrounding components from the environment, and protecting against inadvertent contact of the engine. 
   Typically, these fairings comprise a hood covering (and usually defining) the upper portion of the engine compartment and a belly pan covering (and usually defining, at least in part) the bottom portion of the engine compartment. The fairings may also comprise one or more movable side panels, depending on the particular construction of the vehicle. 
   The prior art snowmobile  1000 , a SKI-DOO™ MX-Z™ manufactured by Bombardier Recreational Products of Valcourt, Canada, shown in  FIGS. 1 and 2  provides a good illustration of conventional fairings. Snowmobile  1000  has a hood  1002  and a belly pan  1004  that form collectively the fairings  1006  of the vehicle. 
   The hood  1002  of the snowmobile  1000  is affixed at the front portion thereof via a conventional hinge (not shown) via bolts or rivets, so that it may swing open about a lateral axis toward the front of the vehicle and permit access to the engine  1008  and other components in the engine compartment. The hood  1002  is shown in  FIG. 1  in a closed position and in  FIG. 2  in an open position. 
   Referring to  FIG. 2 , when the hood  1002  is being opened, to prevent it from over rotating and swinging completely forward and breaking, a wire or small cord  1010  is attached between the hood  1002  and a point on the snowmobile. Thus, in the open position, the hood  1002  is pivoted forward enough so that its center of gravity is forward of the hinge thus urging the hood to flip all the way open. The wire  1010  is long enough to let the center of gravity of the hood  1002  pass the hinge, but not long enough to allow the hood  1002  to over-rotate and break. The weight of the hood  1002  against the wire  1010  holds the hood  1002  in the open position. 
   While this construction is adequate to enjoy the sport of snowmobiling, there are some drawbacks with this design, particularly, in very windy conditions. In this respect, when the hood  1002  is opened in the direction of the blowing wind, the relatively large surface area of the hood  1002  catches a lot of wind. The force created in this situation can be sufficient to break the wire  1010  itself or to cause the wire to become unattached from either the hood  1002  or snowmobile body. Because it is desirable to use components in the manufacture of a snowmobile that are as light as possible (as at times the snowmobile must be moved by hand), the hood  1002  is typically made of plastic. Therefore the force required to break the wire  1010  free from the hood is (typically at its point of attachment to the hood) not that great. A broken hood is clearly undesirable. 
   In a different order of things,  FIG. 3 , which is a partial rear perspective view of the snowmobile  1 , shows one prior art embodiment of how the hood  1002  is held closed (during operation of the snowmobile  1000 ). As shown in  FIG. 3 , a latch fastener  1012  may be employed. The latch fastener  1012  includes an elastic connector  1014  and a hook  1016 . The elastic connector  1014  is anchored or secured to the snowmobile  1000  (typically to a metal portion thereof) using a fastener  1018 . The elastic connector  1014  includes an opening  1020 . The hook  1016  is provided on the hood  1002  and cooperates with the opening to maintain the hood  1002  in a closed position. Specifically, to secure the hood  1002  in the closed position the elastic connector  1014  is stretched until the opening  1020  can be passed over the hook  1016 , and the elastic connector  1014  is released such that the hook  1016  is secured in place via the elastic connector  1014 , preferably under a predetermined tension. In the coupled position, the hook  1016  protrudes through and out of the opening  1020  such that the hook  1016  remains exposed to the surrounding environment. 
   Again, while this configuration is completely adequate to enjoy the sport of snowmobiling, there are some drawbacks to this configuration. Specifically, the hook  1016  is exposed (outside of the fairings) and thus can be contacted while riding or being seated on the snowmobile  1000  such that loose clothing or other material may inadvertently become momentarily caught on the hook  1016 . The hook  1016  is also in plain view and is not aesthetically pleasing. 
   In view of the above, it would be desirable to have a hood attachment system that ameliorates some of the drawbacks noted above with current systems. 
   SUMMARY OF THE INVENTION 
   Thus, as embodied and broadly described herein, in one aspect, the present invention provides a snowmobile, comprising: a frame including a tunnel; an engine supported by the frame; an endless drive track below the tunnel and supported by the frame, the endless drive track being operatively connected to the engine to propel the snowmobile; a straddle seat above the tunnel and supported by the frame; two steering skis forward of the tunnel and supported by the frame; handlebars disposed on the frame forward of the seat, the handlebars being operatively connected to the skis to steer the snowmobile; and fairings supported by the frame, the fairings including a hood, the hood being releasably secured to the snowmobile at least via interlocking male-female connectors, the hood being manually releasable from the snowmobile without the use of tools. 
   The expression “male-female connectors” in the context of the present application includes all mating structures wherein one portion thereof penetrates another in order to interlock the two. For example, it is not necessary that the male potion be perfectly cylindrical or pin shaped, as for example, L-shaped structures should be understood as being included in the male portions. In such a case, the female portion might be a slot into which the L-shaped male portion is first inserted and then slid (into an interlocking position). Nor is it necessary that the mating structures each be singularly male or female, one or both of them could be simultaneously both. 
   The expression “tools” in the context of the present invention includes hand held manual tools such as screwdrivers, wrenches, pliers, and the like; as well as electric or battery operated tools such as drills. It is not meant to include keys that operate locks locking the hood to the snowmobile. 
   One advantage of this aspect of the present invention is that the hood is manually releasable from the snowmobile, such that, should it be desirable to access the engine compartment of the snowmobile under windy conditions, a person may simply remove the hood altogether and place it on the ground next to the snowmobile (for example). Thus he or she need not be concerned with whether the wind will catch the hood and break it, or make it difficult or impossible to maintain the hood in an open position (depending on the orientation of the snowmobile with respect to the wind). Further, the hood is manually releasable from the snowmobile without the use of tools so that it is not necessary to carry any such tools on the snowmobile, thereby eliminating the risk of not having the tool and the weight added by carrying such tools around. Given the generally cold weather conditions in which snowmobiles are operated, it is preferred, although certainly not required, that the hood be manually releasable by gloved hands (as opposed to naked hands). 
   Preferably, there is more than one set of interlocking male-female connectors, most preferably two sets, that releasably secure the hood to the snowmobile. However, depending on the configuration of the hood and snowmobile, a single set would be possible. 
   Preferably, the hood has a forward end and a rearward end and portions of the interlocking male-female connectors disposed on the hood, e.g. in most cases either one of the male connector or the female connector, are located closer to the forward end of the hood than the rearward end of the hood. The forward end and rearward end should be understood as being defined with respect to the forward direction of travel of the snowmobile. 
   It is preferred that the male connectors be disposed on the hood and the female connectors be disposed on the snowmobile. However the reverse configuration, with the female connectors disposed on the hood and the male connectors disposed on the snowmobile, is also within the scope of the present invention. 
   While no particular shape of the male connectors is required, it is preferred that the male connectors be shaped such that securing the hood to the snowmobile through insertion of the male connectors into the female connectors requires movement of the hood in more than one direction. An example would be the preferred L-shaped male connector described above. This would discourage inadvertent releasing of the hood from the snowmobile. 
   In addition to the interlocking male-female connectors, it is preferred that the hood be further releasably secured to the snowmobile via a hook and an elastic connector having an opening therein for receiving the hook. It is more preferred that one of the hook and elastic connector be disposed on the hood closer to the rearward end of the hood than to the forward end of the hood. 
   Where such hooks and elastic connectors are employed, it is highly preferred that the fairings further include a section movable between an open position and a closed position, that the fairings be constructed and arranged on the snowmobile such that in the closed position, the section conceals the hook and the elastic connector from view and/or covers the hook and the elastic connector. This aspect of the invention is described below. 
   In another aspect, as embodied and broadly described herein, the present invention provides a hood suitable for use on a snowmobile having: a frame including a tunnel; an engine supported by the frame; an endless drive track below the tunnel and supported by the frame, the endless drive track being operatively connected to the engine to propel the snowmobile; a straddle seat above the tunnel and supported by the frame; two steering skis forward of the tunnel and supported by the frame; handlebars disposed on the frame forward of the seat, the handlebars being operatively connected to the skis to steer the snowmobile; a system for releasably securing the hood to the snowmobile without the use of tools, the system including portions of male-female connectors disposed on the snowmobile and at least one of a hook and a corresponding elastic connector with an opening; the hood comprising: a body; portions of male-female connectors disposed on the body and configured to mate with the portions of male-female connectors disposed on the snowmobile; and at least the other of the hook and the corresponding elastic connector disposed on the body. 
   In yet another aspect, as embodied and broadly described herein, the present invention provides a method of releasably securing, without the use of tools, a hood on a snowmobile, the snowmobile having, a frame including a tunnel; an engine supported by the frame; an endless drive track below the tunnel and supported by the frame, the endless drive track being operatively connected to the engine to propel the snowmobile; a straddle seat above the tunnel and supported by the frame; two steering skis forward of the tunnel and supported by the frame; handlebars disposed on the frame forward of the seat, the handlebars being operatively connected to the skis to steer the snowmobile; a system for releasably securing the hood to the snowmobile without the use of tools, the system including portions of male-female connectors disposed on the snowmobile and at least one of a hook and a corresponding elastic connector with openings; the hood having, a body; portions of male-female connectors disposed on the body and configured to mate with the portions of male-female connectors disposed on the snowmobile; and at least the other of the hook and the corresponding elastic connector disposed on the body; the method comprising: (i) interlocking the portions of the male-female connectors disposed on the hood with the portions of the male-female connectors disposed on the snowmobile through movement of the hood; (ii) stretching one of the elastic connectors; (iii) passing the opening of the stretched elastic connector over its corresponding hook; (iv) releasing the stretched elastic connector; and (v) if there is more than one elastic connector, repeating steps (ii) to (iv) for each of the elastic connectors of the system. 
   In the context of the present invention, it should be understood that the movable fairing section concealing the hook and elastic connector need not be of any particular shape or size as long as it is shaped and sized to carry out, in whole, or in part in cooperation with other movable fairing sections, its intended function, i.e. to conceal the hook and the elastic connector from view. In the latter case, i.e. where more than one movable fairing sections cooperate to conceal the hook and elastic connector from view, all such coopering sections should be considered to together be a “section” in the context of the present invention. 
   In the context of the present invention, the difference between the section concealing the hook and/or elastic connector from view and covering the hook and/or elastic connector is in that the latter, holes or see-through portions or the like are permitted in the section such that the hook and/or the elastic connector could be seen but not accessed when the section is in the closed position, whereas in the former the hook and/or elastic connector could not be seen. 
   One advantage of this aspect of the present invention is that the hook and elastic connector securing the hood to the snowmobile are concealed during the operation of the snowmobile. Thus, it is far more difficult for either the hook or the elastic connector to be inadvertently contacted by a user or other material during the operation of the snowmobile. In addition, some people will find this configuration (with the hook and the elastic connector out of view or covered), aesthetically pleasing. 
   Preferably, the hood is releasably secured to the snowmobile via a plurality of hooks and elastic connectors, and the fairings include a plurality of sections movable between open positions and closed positions, and the fairings are constructed and arranged on the snowmobile such in their closed positions, the sections conceal the hooks and the elastic connectors from view or cover them. In this manner, there can be at least one set of hooks and elastic connectors on each side of the snowmobile, to better secure the hood to vehicle, and each such set will have a corresponding movable fairing section to conceal it from view or cover it when closed. Preferably, there is a one to one correspondence between each pair of corresponding hooks and elastic connectors and each movable section, however, embodiments where a single movable section conceals more than one set of hooks and elastic connectors are also considered to be within the scope of the present invention. 
   Other aspects, objects and features of the invention will become apparent by reference to the following description and the drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Having thus generally described the nature of the invention, reference will now be made to the accompanying drawings, showing by way of illustration preferred embodiments thereof and in which: 
       FIG. 1  is a side view of a prior art snowmobile; 
       FIG. 2  is a side view of the snowmobile shown in  FIG. 1 , with the hood in a partially-open position; 
       FIG. 3  is a partial rear perspective view of a snowmobile showing one embodiment of how a snowmobile hood is held closed in the prior art; 
       FIG. 4  is a perspective view of a snowmobile equipped with a hood attachment system of the present invention (among other features). 
       FIG. 5  is a rear perspective view of a hood according to one embodiment of the present invention; 
       FIG. 6  is a front perspective view of the hood shown in  FIG. 5 ; 
       FIG. 7  is a partial front perspective view of the hood shown in  FIGS. 5 and 6 , in a tilted position for installation on the snowmobile; 
       FIG. 8  is a partial rear perspective view of a snowmobile of the present invention showing how the front of the snowmobile hood couples with the snowmobile in one embodiment of the present invention; 
       FIG. 9  is a partial rear perspective view of the snowmobile showing how the rear of the snowmobile hood attaches to the snowmobile in one embodiment of the present invention; 
       FIG. 10  is a partial rear perspective view of the snowmobile showing one of the side panels swung open to allow access to the point at which the rear of the snowmobile hood is attached to the snowmobile; 
       FIG. 11  is a partial rear perspective view of the snowmobile showing one of the side panels in the closed position in one embodiment of the present invention; and 
       FIG. 12  is a partial rear perspective view of the latch maintaining one of the side panels in the closed position being disengaged to allow the side panel to be opened. 
   

   In the drawings, preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood that the description and drawings are only for purposes of illustration and as an aid to understanding, and are not intended to be a definition of the limits of the invention. 
   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   Referring now to  FIG. 4 , a snowmobile incorporating embodiments of the present invention is designated generally by reference numeral  10 . This snowmobile is commercially available from Bombardier Recreational Products of Valcourt, Canada under the designation SKI-DOO™ FREESTYLE™. Although certain aspects of the present invention are applicable in other types of vehicles, the present invention has particular utility in connection with snowmobiles. 
   The snowmobile  10  includes a forward end  12  and a rearward end  14  which are defined consistently with a travel direction of the vehicle. The snowmobile  10  includes a frame or chassis  16  which normally includes a rear tunnel  18 , an engine cradle portion  20  and a front suspension assembly portion  22 . An engine  24 , which is schematically illustrated in  FIG. 4 , is carried by the engine cradle portion  20  of the frame  16 . A ski and steering assembly (not indicated) is provided, in which two skis  26  are positioned at the forward end  12  of the snowmobile  10  and are attached to the front suspension assembly portion  22  of the frame  16  through a front suspension assembly  28 . The front suspension assembly  28  includes ski legs  30 , supporting arms  32  and ball joints (not shown) for operatively joining the respective ski legs  30 , supporting arms  32  and a steering column  34 . The steering column  34  at its upper end is attached to a steering device such as a handlebar  36  which is positioned forward of a rider and behind the engine  24  to rotate the ski legs  30  and thus the skis  26 , in order to steer the vehicle. 
   An endless drive track  38  is positioned at the rear end  14  of the snowmobile  10  and is disposed under tunnel  18 , being connected operatively to the engine  24  through a belt transmission system  40  which is schematically illustrated by broken lines in  FIG. 4 . Thus, the endless drive track  38  is driven to run about a rear suspension assembly  42  for propulsion of the snowmobile  10 . The rear suspension assembly  42  includes a pair of slide rails  44  in sliding contact with the endless drive track  38 . The rear suspension assembly  42  also includes one or more shock absorbers (not shown) which may further include a coil spring (not shown) surrounding the individual shock absorbers . Front and rear suspension arms (not shown) are provided to attach the slide rails  44  to the frame  16 . One or more idler wheels  52  are also provided in the rear suspension assembly  42 . 
   At the front end  12  of the snowmobile  10 , fairings  54  enclose the engine  24  and the belt transmission system  40 , thereby providing an external shell that not only protects the engine  24  and the belt transmission system  40 , but can also be decorated to make the snowmobile  10  more aesthetically pleasing. Typically, the fairings  54  include a hood  55  and one or more side panels  56  which can be opened to allow access to the engine  24  and the belt transmission system  40  when this is required, for example, for inspection or maintenance of the engine  24  and/or the belt transmission system  40 . In the particular snowmobile  10  shown in  FIG. 4 , the side panels can be opened along a vertical axis to swing away from the snowmobile  10 . A windshield  41  is connected to the hood. The windshield  41  acts as a wind screen to lessen the force of the air on the rider while the snowmobile  10  is moving. 
   The engine  24  is a type of internal combustion engine that is supported on the frame  16  and is located at the engine cradle portion  20 . The internal construction of the engine  24  may be of any known type, however the engine  24  drives an engine output shaft (not shown) that rotates about a horizontally/laterally disposed axis that extends generally transversely to a longitudinal centerline  61  extending in a front to rear direction of the snowmobile  10 . The engine output shaft drives the belt transmission system  40  for transmitting torque to the endless drive track  3   8  for propulsion of the snowmobile  10 . 
   A straddle seat  58  is positioned atop the tunnel  18  of the frame  16  and extends from the rear end  14  of the snowmobile  10  to the fairings  54 . A rear portion  59  of the seat  58  may include a storage compartment or can be used to accommodate a passenger seat. Two footrests  60  are positioned on opposite sides of the snowmobile  10  below the seat  58  to accommodate the driver&#39;s feet. 
     FIGS. 5 and 6  show a rear and a front perspective view, respectively, of the removable hood  55  according to an embodiment of the present invention. The hood  55  includes two male connectors in the form elongated L-shaped fingers  110  and  111  attached to the underside of the front portion and two rubber elastic connectors  112  and  113  fixed to the underside of the rear portion. Although the rubber elastic connectors  112  and  113  are fixed to the hood  55 , they can be removed and replaced in case of breakage. The hood  55  further comprises a central opening  114  in its front face to accommodate a headlight structure and two openings  116  and  117  in its rear face to accommodate two analog or digital displays.  FIG. 4 . shows that the hood  55  also includes a windshield  41 . 
   To install the hood  55  on the snowmobile  10 , the rear portion of the hood  55  is tilted slightly towards the front  12  of the snowmobile  10  and the front portion of the hood is tilted slightly downward towards the ground. This position of the hood  55  is depicted in the partial perspective view of the snowmobile  10  in  FIG. 7 . The hood  55  is then moved forward and downward and rotated in direction  100  until the elongated fingers  110  and  111  engage with corresponding female connectors, slots  118  and  119  in the front fairing  117  to hold the front portion of the hood  55  in place.  FIG. 8  shows finger  110  in an engaged position with slot  118 , and finger  111  not yet in an engaged position with slot  119 . Once finger  111  is in the engaged position with slot  119 , the rear portion of the hood can then be lowered in direction  105  shown in  FIG. 7  until fitted appropriately on the vehicle. The elastic members  112  and  113  are then engaged with hooks  120  (not shown) and  122  by stretching and positioning them such that the openings therein engage the hooks  120  and  122  on the frame  16  thus discouraging the hood  55  from moving relative to the frame  16 .  FIG. 9  shows the elastic member  113  in the process of being engaged with the hook  122 . 
   To remove the hood  55  from the frame  16  of the snowmobile  10 , the elastic members  112  and  113  are first disengaged from hooks  120  and  122 , again by stretching. The rear portion of the hood  55  is then lifted in a direction opposite to direction  105  in  FIG. 7 . The hood  55  is then slid in a direction opposite to direction  100  until fingers  110  and  111  are disengaged from slots  118  and  119  thus freeing the hood from the snowmobile  10 . 
   According to another embodiment, a side panel  56 , which opens about a generally vertical axis at the front of the snowmobile  10  conceals the elastic members  112  and  113  and the hooks  120  and  122  from view (and covers them) when the side panel  56  is in the closed position.  FIG. 11  shows the side panel  56  in the closed position.  FIG. 10  shows the side panel  56  in the open position. The side panel  56  pivots about a hinge  126  and swings towards the front  12  of the snowmobile  10  to open. A latch means  128  shown in  FIG. 11  secures the side panel to the frame  16  when the side panel  56  is in the closed position as is depicted in  FIG. 11 . 
   Before the hood  55  can be removed, the side panel  56  must be opened.  FIG. 12  shows how the latch means  128  is disengaged from the side panel  56  to allow the side panel  56  to swing into the open position. When the side panel  56  is in the open position, the rubber elastic members  112  and  113  are accessible to the user and can be disengaged from the hooks  120  and  122  to allow the hood  55  to be removed. 
   In another preferred embodiment, the design of the hood  55  and side panel  56  include multi-dimensional planes which enhance the aerodynamic utility and the aesthetic appeal of the snowmobile  10 . 
   In an alternative embodiment (not shown), two elongated fingers are attached to the front of the frame  16  or front fairing  117 . These fingers engage with corresponding slots in the removable hood  55  in an interlocking male-female arrangement. 
   The above description of preferred embodiments should not be interpreted in a limiting manner since other variations, modifications and refinements are possible within the spirit and cope of the present invention. The scope of the invention is defined in the appending claims and their equivalents.