Abstract:
A modular snowmobile ski is provided with a base that has longitudinally extending retainers, as shown, slots, or longitudinally extending slidable engaging projections that will accept ribs, keels, and the like with complimentary retainers. Various types of center keels or ribs can be provided for changing the aggressiveness of the ski, that is, the amount the ski will bite into the snow. Stabilizing or tracking ribs also can be provided along the ski edges. The base of the ski is provided with retainers that will hold side extensions in place on the ski when desired.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     The present application is based on and claims the benefit of U.S. provisional patent application Ser. No. 60/617,916, filed Oct. 12, 2004, the content of which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The present invention relates to a snowmobile ski that permits adding ribs that can form a keel, side ribs and snow deflectors, and other modules to tune the ski for use, and make it adaptable for trail riding, racing, and general use. The modules are added to the sides and/or the underside of the ski.  
         [0003]     Snowmobile skis generally have formed keels that are molded in place on the bottom of the ski. Ribs projecting from the bottom along the sides of the ski are also known, when molded or formed in place. Most snowmobile skis are molded from synthetic materials. The control offered by the various keel shapes available is not suitable for all uses. A rider may have different desires as far as the ability to control the snowmobile, and if any changes are to be made to improve control, the changes usually require replacing an entire ski.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention relates to a modular snowmobile ski that has modular replaceable components, particularly for the bottom side of the ski. A replaceable center keel permits changing the aggressiveness or bite of the keel easily and simply. Also, modular ribs may be added to or removed from the ski, at locations outboard of the center keel for superior directional control, turning and tracking.  
         [0005]     The bottom portion of the ski of the present invention is provided with longitudinal dovetail slots, or other configurations or types of retainers that will receive slide in ribs. In addition, the center keel has a sturdy longitudinal T-bar support extending the desired length of the ski, and the keels that are used have T-slots that slide onto the T-bars or supports and then can be latched or retained in place. For example, an end wear bar that will hold the keel in place can be used.  
         [0006]     In one form of the invention, a snow diverter or deflector module is placed on the ski to direct snow toward the center of the snowmobile to lubricate the track when the snowmobile is going over hard ground, or places where there is not an adequate covering of snow in the center.  
         [0007]     Another aspect is the addition of outer edge slides that extend the width of the ski.  
         [0008]     The configuration is such that the base ski and the replaceable modules can be easily molded from suitable durable plastics. The keels, ribs and defectors can easily be inserted and replaced. The ribs and keels can be formed on a full width modular slide that spans the entire bottom of the ski base and is retained as a bottom unit.  
         [0009]     Front ski handle retainers are molded in place on the ski, and a molded handle can be removably attached. The handle can be changed as well. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]      FIG. 1  is a side elevational view of a snowmobile ski made according to present invention;  
         [0011]      FIG. 2  is a top plan view of the ski of  FIG. 1 ;  
         [0012]      FIG. 3  is a sectional view taken generally along line  3 - 3  in  FIG. 2  showing details of a handle mounting;  
         [0013]      FIG. 4  is a sectional view taken generally along line  4 - 4  in  FIG. 1  showing the cross-section of the rear portion of the ski;  
         [0014]      FIG. 5  is a perspective view of a typical longitudinally extending rib that is removed from the ski;  
         [0015]      FIG. 6  is a sectional view taken along the same line as  FIG. 4 , and showing modifications including side extensions that can be provided on the sides of the ski;  
         [0016]      FIG. 7  is a bottom plan view of the ski of  FIG. 6 ;  
         [0017]      FIG. 8  is a sectional view taken on substantially the same line as  FIG. 4  showing a type of a modular keel installed on the ski;  
         [0018]      FIG. 9  is a perspective view of the modular keel shown in cross-section in  FIG. 8 ;  
         [0019]      FIG. 10  is a cross-sectional view of the ski illustrating a flexible carbide section keel that is installed on the ski;  
         [0020]      FIG. 11  is a side view of the flexible carbide steel keel;  
         [0021]      FIG. 12  is a bottom plan view of the ski having a carbide keel insert shown in  FIG. 11 ;  
         [0022]      FIG. 13  is a cross sectional view of a ski having a modified keel and ski module;  
         [0023]      FIG. 14  is a cross section of the keel and rib module shown on a ski in  FIG. 12 ;  
         [0024]      FIG. 15  is a fragmentary cross-sectional view of a ski having an outwardly diverging edge surface to provide a sideward directed spray of snow;  
         [0025]      FIG. 16  is a bottom view of the ski portion shown in  FIG. 15 ;  
         [0026]      FIG. 17  is a side view of the replaceable ski handle shown in  FIGS. 1 and 2 ;  
         [0027]      FIG. 18  is a bottom view of the handle of  FIG. 16A ;  
         [0028]      FIG. 19  is a perspective view of the handle of  FIG. 16A ; and  
         [0029]      FIG. 20  is a sectional view taken on line  20 - 20  in  FIG. 17 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0030]      FIGS. 1 and 2  show a snowmobile front steering ski indicated generally at  10  that is provided with an attachment bracket  12  for attaching it to the steering spindles of the snowmobile (not shown). The ski  10  has a base portion  14  that extends longitudinally, with a turned-up tip portion  16 , and a tail portion  18 . The attachment bracket or mounting bracket  12 , as can be seen in  FIG. 2 , comprises a pair of spaced upright walls  20 , on which suitable metal bracket connectors  22  are mounted in a suitable place. Additionally, the tip portion  16  of the ski has a handle  24  attached to the top thereof. The handle  24  is replaceable as will be further explained.  
         [0031]     Referring to  FIG. 4 , it can be seen that base portion  14  of the ski, has a plurality of longitudinal dovetail slots  28 A,  28 B,  28 C, and  28 D. The slots  28 A- 28 D extend longitudinally, and are of suitable size for the uses and loads involved. The dovetail slots form first parts of interfitting modular member retainers.  
         [0032]     The dovetail slots  28 A- 28 B can be used for retaining slide-in longitudinal traction guide and control ribs. In  FIG. 4 , which is an exploded view, four different types of longitudinal ribs are shown. These include a trapezoidal cross section rib  30 , a triangular cross section rib  32 , a rib  34  that has concave or inwardly scalloped sides, and a rectangular cross section rib  36 . One or more of these cross sectional shape ribs can be inserted and held in the slots  28 A- 28 D. The ribs on a ski can all be the same shape, or can be more than one shape, depending on the desired results. For example, it may be desirable to have the trapezoidal shaped ribs  30  attached through the outer grooves  28 A and  28 D, and the triangular shaped ribs  32  attached through the inner grooves  28 B and  28 C. If desired, one of the other cross section shape ribs could be placed in the inner grooves. The dovetail flanges on the ribs form second parts of the interfitting modular member retainers.  
         [0033]      FIG. 5  shows a full length view of the rectangular cross-section rib  36 , and it can be seen that the dovetail slide tops of all of the ribs have dovetail flanges illustrated generally with an “A” designation after the rib number. For example, the dovetail flanges  36 A are on the rib  36 , dovetail flanges  34 A are on the rib  34 , and dovetail flanges  30 A and  32 A are on the ribs  30  and  32 , respectively. These dovetail flanges are shaped and sized to slide into the dovetail slots  28 A- 28 D. The longitudinal ribs can be latched or locked in place in any desired manner including set screws, pins or the like, or by merely placing removable blocks at the ends of the dovetail slots to block longitudinal movement or sliding of the ribs along the slots. The ribs are installed by sliding them along the dovetail slots.  
         [0034]      FIG. 6  shows a modified base  14 A of a ski, and in this case, base  14 A has the dovetail slots  28 A- 28 D as before, but it also has longitudinal dovetail slots  40 A and  40 B that are formed on the side edge surfaces of the ski. This permits an elongated longitudinal side or width extension flange  42  to be placed into the dovetail slot  40 A, and held in place in a suitable manner so that it would have an appearance from the bottom that is shown in  FIG. 7 .  
         [0035]     As a variation of construction, a concave, rounded or part cylindrical recess  41  is formed at the lower side edge of the side extension  42 . The concave recess  41  extends the length of the ski. As shown in  FIG. 7 , a snow diverter surface  41 A at the rear portion of the concave recess concave slot  41  tapers laterally outwardly to spray snow toward the center of the snowmobile on which the ski is mounted. The snow spray is to help provide track slide lubrication. The snow diverter surface  41 A provides a spray right onto the track and track slide of the snowmobile (not shown).  
         [0036]     The dovetail slot  40 B on the opposite side of the ski base  14 A has an elongated longitudinal side extension  44  installed and held in dovetail slot  40 B. The side extension  44  also includes a depending edge rib  47  along the outer side thereof, to provide for additional control. The surface of the rib  47  also can have an outwardly tapered rear end surface to provide a snow spray toward the track if the rib is on a side of the ski adjacent the track.  
         [0037]     As shown in  FIG. 7  in the bottom view, the side extensions  42  and  44  extend forwardly to where the ski tip starts to curve upwardly, and extend all the way to the rear end. The rear ends of the side extension can be tapered or cut as shown for smoothness or streamlining.  
         [0038]     The bottom view of  FIG. 7  also shows longitudinal ribs  30 ,  32 ,  34  and  36  in the slots  28 A- 28 D. The ribs can be any desired cross-sectional shape, in addition to the shapes previously specifically discussed.  
         [0039]     In addition to the dovetail slots, the ski base  14 , and also the ski base  14 A, are provided with a T-shaped longitudinally extending protruding support  48 , in the center or keel region of the ski. The T-shaped support  48  forms a first part of an interfitting modular member retainer. The T-shaped support  48  is shown in  FIG. 4  with a rectangular cross-sectional keel  50  slid into place. In  FIG. 6 , the T-shaped support  48  is shown with a trapezoidal keel  52 , which is shown in cross-section with sharper corners at the bottom side edges to be more aggressive and helping to keep the ski from sliding sideways. The ribs and the keel sections can all be molded from a suitable plastic or other synthetic material, and can be brightly colored if desired.  
         [0040]      FIGS. 8 and 9  show a further modified keel  56  in position. The keel  56  has a triangular cross section bottom portion with a longitudinal edge  57 . The keel  56  has a T-shaped slot  58  that slides over the T-shaped support  48  as shown.  FIG. 9  shows the length of the triangular keel  56 , for illustrative purposes, with the slot  58 . The slot  58  has an opening along its length and can be slid onto the T-shaped support  48 . T-shaped supports and slots can also be provided for holding ribs instead of the dovetail slots and flanges, if desired. The T-shaped slots that slide onto the T-shaped supports form second parts of interfitting modular member retainers that are T-shaped.  
         [0041]      FIGS. 10, 11  and  12 , show a base  14  of a snowmobile ski with a sectional, longitudinally flexible carbide keel  60  in position. The carbide keel  60  has a body  61  that has a T-shaped slot that slides over the T-shaped support  48 . The body  61  also has a lower longitudinally extending slot  62  in which carbide steel segments  64  are positioned and held with suitable fasteners  66  or held in other ways. The carbide steel segments  64  form runners that are embedded into and held by a support or frame  68 , and held in place. The supports or frames  68  are formed as short sections, so that the body or support housing  61  can flex slightly when the ski flexes without breaking the carbide inserts. Also as can be seen, the carbide inserts have sharpened lower edges  70  for gripping ice and hard surfaces.  
         [0042]      FIG. 12  is a bottom view of the ski  14  that shows the carbide keel  60  in position, with the individual steel segments  64  shown. The carbide sections  64  protrude from the body  61  along a short portion of the length of the ski. The number of carbide keel sections  60  can be varied, as desired.  
         [0043]     In  FIGS. 13 and 14 , a unitary bottom rib and keel wear base or plate attachment  71  that can be slid onto a base  14 A is shown. The wear base attachment  71  can be provided with keel structures, ribs, and/or also side extensions as illustrated. The ski base  14 A, which has the bottom dovetail slots as shown in  FIG. 6 , and also slots along the side edges, is used for mounting the molded modular wear base attachment  71 , and as can be seen, the wear base attachment has dovetail slides  72  that will fit into the dovetail grooves  28 A- 28 D as well as side slides  72  that slide into the side grooves  40 A and  40 B. In addition, the keel wear base  71  has a center keel section  74  with a T-shaped slot  76  that will slide over the T-shaped support  48  on the base  14 A.  
         [0044]     The keel wear base or plate  71  includes ski side extensions  78  and  80 . The wear base or plate  71  can be slid into the dovetail slots of the base  14 A and along the T-shaped support  48 , so that the assembly is made as shown in  FIG. 13 .  FIG. 14  shows the modular keel wear base  71  separately. Ribs  82  extend downwardly from the lower surface of the keel wear base  71 .  
         [0045]     A T-shaped rib or support  84  is provided in the center of the keel wear base for receiving keel members that have slots that slide on the T-shaped support  48 . The keel members would be held in place as discussed previously.  
         [0046]     A single molded replacement modular keel wear base can be slid into place on a ski base. The modular keel wear base can have molded in ribs and side extensions. The keel wear base  71  includes a support  84  for adding a keel member in the center. The modular keel wear base will slide easily onto a ski base  14 A so that the user can change the entire base configuration at once as a modular unit, if desired.  
         [0047]      FIGS. 15 and 16  show the concave snow spray diverter surface on a ski base  14 A without side extensions. The ski base  14 A has a longitudinal part cylindrical concave surface or recess  100  that will rest on snow as the ski moves forwardly in the direction shown by arrow  102  in  FIG. 16 . The surface  100  joins an outwardly tapered, concave surface section  104  at the rear of the ski base  14 A. This sprays snow toward the track slide to help in lubricating the track.  
         [0048]     Other laterally outwardly tapered surface shapes can be used. For example, a rear portion of one of the ribs can incline toward the center. A side surface of one of the ribs can be inclined. The inclined surface should be near or at the inside edge of the ski.  
         [0049]     In  FIGS. 17-20 , the handle  24  is illustrated. The handle  24  is shown removed from the snowmobile ski, and it can be seen that it is curved in an arch, with a pin receiving hole  92  at one end, so it can be pinned to ski brackets, and a type of a T-shaped retaining lug  94  at its other end that can be slid into a slot on the tip of the ski. The handle  24  can be easily replaced and held in position. A lock pin hole  96  is provided to receive a pin to lock the handle  24  in place. Replacement of the retainer pins can be done easily, and the handle  24  will slip into place with the T-shaped retainer  94 . Then the hub  91  that has the hole or bore  92  will be put into the place and the retainer pins then passed through the brackets on the ski to hold the handle  24 . The handle  24  can thus be replaced easily as a modular component.  
         [0050]     The center keel shown can extend all the way forwardly to where the handle fastens in place, and the handle  24  can form a stop to prevent the keel from being removed. This is generally shown at  FIG. 3 , where the handle is in cross-section.  
         [0051]     The skis can be for snowmobiles as described, or for other power vehicles used in snow, such as all terrain vehicles adapted for snow use.  
         [0052]     Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.