Patent Abstract:
A snow lubrication device attaches to a vehicle body of a snowmobile and includes a pair of snow rake rods extending from the vehicle body to contact a snow surface. A snow rake member located at the end of the snow rake rod scatters snow. The scattered snow lubricates gaps between a track belt and the slide rail and/or between the track belt and the drive wheel. The lubrication of the track belt improves operation of the snowmobile if the lower part of the snow rake rod strikes a stone or the like, the snow rake rod temporarily deflects further rearward. The snow lubrication device has relatively few components, is low in cost, and is hard to dislodge from a snowmobile.

Full Description:
RELATED APPLICATIONS 
   The present application is based on and claims priority under 35 U.S.C. §119(a)-(d) to Japanese Patent Application No. 2005-026039, filed on Feb. 2, 2005, the entire contents of which are hereby expressly incorporated by reference herein. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a snow lubrication device for a snowmobile. Preferably, the snow lubrication device is attached to the front of the snowmobile and lubricates the gap between a track belt and a part of the snowmobile that is in contact with the track belt by raking and scattering snow. 
   2. Description of the Related Art 
   Snowmobiles are conventionally used by people moving on snowfields or the like in snowy regions. In the snowmobile, a track belt is routed around and between a drive wheel and a rear wheel. The snowmobile runs forward as the track belt is driven and circulated by the drive of an engine. In some snowmobiles, part of the track belt in contact with the drive wheel or part of the track belt in contact with a slide rail is lubricated. A snow rake-up means on the front of the vehicle body or on the underside of the steering skis scatters snow toward the rear part of the track belt. 
   These known snow rake-up means include a swing arm that extends in up and down directions in a rotatable state to the underside part of the vehicle body. The snow rake-up means provides a stopper for preventing the swing arm from moving forward beyond a specified position and a spring for urging a lower part of the swing arm forward. Therefore, when the snowmobile runs, the lower end of the swing arm rakes up and scatters snow toward the rear. When the lower end of the swing arm strikes earth or small stones under the snow surface, the swing arm moves back against the resilience of the spring, which prevents shock from being transmitted to the vehicle body. However, the snow rake-up means is complicated and costly due to the parts such as the spring and stopper. 
   SUMMARY OF THE INVENTION 
   An aspect of the present invention is directed toward addressing one or more of these problems and provides a snow lubrication device having a simple structure that lubricates a drive belt. Preferably, the snow lubrication device is attached to the front of the snowmobile and lubricates the gap between a track belt and a part of the snowmobile in contact with the track belt by raking and scattering snow. A snow lubrication device, which is configured in accordance with the embodiments disclosed herein, is simpler, lower in cost, and is less likely to become dislodged from the vehicle body. 
   When the track belt is pressed against the snow surface, the snow lubrication device scatters snow on the snow surface to lubricate the contact part of the track belt and part of the snowmobile in contact with the track belt. The snow lubrication device comprises a fixing member made up of a fixing part fixed to the front side part of the vehicle body of the snowmobile. The fixing member includes a cylindrical member into which a rod-shaped member having elasticity with its one end part is inserted, clamped, and/or fixed. The snow lubrication device also includes a snow rake member with its root end part fixed to the other end part of the rod-shaped member. A front-end of the snowmobile is formed with a blade part for raking snow. 
   The rod-shaped member can be fixed to the fixing member by clamping and fixing one end part of the rod-shaped member by applying a force to the outside round surface of the cylindrical part in the state of one end part of the rod-shaped member being inserted into the cylindrical part of the fixing member. Therefore, it is possible to firmly fix the rod-shaped member and the fixing member. Further, clamping and fixing can be accomplished by a crimping process. The parts of the snowmobile in contact with the track belt of the snowmobile include the drive wheel, the slide rail, or the like. 
   The joint between the fixing member and the rod-shaped member can be covered with a seal member. In this way, water is prevented from finding its way into the joint. In embodiments where the rod-shaped member is made of metal, covering the joint with a seal member inhibits rust from forming. The seal member may also improve the appearance of the joint between the fixing member and the rod-shaped member. 
   The root end part of the snow rake member can be thinner than the other end part of the rod-shaped member. The rod-shaped member can be fixed to the snow rake member by putting the root end part of the snow rake member end to end with the other end of the rod-shaped member. A cylindrical fixing member can be fitted over the end-to-end joint and fixed by clamping. The gap between the cylindrical fixing member and the root end part of the snow rake member can be at least partially filled with adhesive. In this way, the snow rake member has a reduced size and weight. Further, because the gap between the cylindrical fixing member and the root end part of the snow rake member is at least partially filled with adhesive, the snow rake member is firmly fixed through the cylindrical fixing member to the rod-shaped member, although the root end part of the snow rake member is thinner than the other end part of the rod-shaped member. 
   The joint part of the cylindrical fixing member and the rod-shaped member can be covered with a seal member. Water is prevented from finding its way into the joint area between the cylindrical fixing member and the rod-shaped member. Further, if the rod-shaped member is made from a metal prone to rust corrosion, a seal member covering the outside surface of the rod-shaped member or part of the rod-shaped member joined to the cylindrical fixing member can inhibit such corrosion or rusting. By covering the joint area between the cylindrical fixing member and the rod-shaped member with the seal member, the external appearance also can be improved. 
   A snow lubrication device is also proposed in which a wire having pliability is used in place of the swing arm design described above. To fix the wire of this snow lubrication device to the vehicle body of the snowmobile, one end of the wire is inserted into a hole formed in a fixing member and stopped with a screw. The wire is fixed through the fixing member to the vehicle body. In some applications, vibrations or other conditions may cause the screw or other fattener to become dislodged. With this snow lubrication device, however, it is possible that the screw for fixing the wire to the fixing member may loosen, resulting in the wire being dislodged from the fixing member. 
   Another aspect is a snow lubrication device for a snowmobile for running on snow. The snow mobile has an endless track belt driven with a drive wheel by the drive of an engine, wherein the track belt is pressed against the snow surface, and wherein the snow lubrication device is configured to be attached to a front portion of the snowmobile for raking and scattering snow on the snow surface. The scattering snow lubricates a contact part between the track belt and a part of the snowmobile that is in contact with the track belt. The snow lubrication device comprises a fixing member comprising a fixing part fixed to the forward portion of the vehicle body of the snowmobile and a cylindrical member, a rod-shaped member having elasticity having a first end part coupled with the cylindrical part of the fixing member, and a snow rake member having a root end part coupled with a second end part of the rod-shaped member and having a front-end formed with a blade part for raking snow. 
   Another aspect is a snow lubrication device for a snowmobile having an endless track belt driven with a drive wheel by an engine, the snow lubrication device being attached to a front portion of the snowmobile. The snow lubrication device comprises a fixing member comprising a fixing part, the fixing part enabling the snow lubrication device to be fixed to the front portion of the snowmobile, an elastic rod-shaped member extending from the fixing member, and a snow rake member having a root end and a blade, the root end being fixed to the rod-shaped member, the blade being configured to rake and scatter snow to lubricate a contact region between the endless track belt and the snowmobile. 
   Another aspect is a snowmobile having a snow lubrication device attached to a front portion of the snowmobile and configured to rake and scatter snow to lubricate a contact region between an endless track belt and the snowmobile. The snowmobile comprises an engine, a drive wheel driven by the engine, an endless track belt driven by the drive wheel, and a seat located on a rear upper part of the snowmobile. The snowmobile further comprises handlebars configured for a rider to control a direction of movement for the snow mobile, a fixing member comprising a fixing part, the fixing part enabling the snow lubrication device to be fixed to the front portion of the snowmobile, an elastic rod-shaped member extending from the fixing member, and a snow rake member having a root end and a blade, the root end being fixed to the rod-shaped member, the blade being configured to rake and scatter snow to lubricate a contact region between the endless track belt and the snowmobile. 
   An aspect is a method for lubricating a contact region between an endless belt and a snowmobile having a snow lubrication device attached to a front portion of the snowmobile. The method comprises configuring an endless belt to contact against a snow surface so as to move a snowmobile in a forward direction, configuring to scatter snow at a location forward of the contact between the endless belt and the snow surface, configuring to direct the scattering snow rearward and toward said endless belt, configuring to lubricate the endless belt with the scattering snow, configuring to contact a snow lubrication device with a rock on the snow surface, and configuring to elastically deform the snow lubrication device as a result of the contact with the rock. 
   Another aspect is a method for manufacturing a snow lubrication device for a snowmobile, the snowmobile having an endless track belt driven with a drive wheel rotated by the drive of an engine. The method comprises providing a fixing member having a fixing part configured to be fixed to the snowmobile and a cylindrical member, inserting an end part of a rod-shaped member having elasticity into the cylindrical member of the fixing member, clamping the end part within the cylindrical member, and fixing a root end of a snow rake member to the other end part of the rod-shaped member, a rearward facing end of the snow rake member having a blade part configured to rake snow. 
   The systems and methods of the invention have several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of the invention as expressed by the claims which follow, its more prominent features have been discussed briefly above. After considering this discussion, and particularly after reading the section entitled “Detailed Description of the Preferred Embodiments” one will understand how the features of the system and methods provide several advantages over traditional snow lubrication systems. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     These and other features, aspects and advantages of the present invention will now be described in connection with preferred embodiments of the invention, in reference to the accompanying drawings. The illustrated embodiments, however, are merely examples and are not intended to limit the invention. The following are brief descriptions of the drawings. 
       FIG. 1  is a side view of a snowmobile having a snow lubrication device according to a first embodiment of the invention. 
       FIG. 2  is a plan view of the snowmobile shown in  FIG. 1 . 
       FIG. 3  is an enlarged front side view of the snowmobile and snow lubrication device according to the first embodiment. 
       FIG. 4  is a plan view of the snowmobile from  FIG. 3 . 
       FIG. 5  is a front face view of a snow rake rod from the snow lubrication device for use on the left side of the snowmobile. 
       FIG. 6  is a side face view of the snow rake rod from  FIG. 5 . 
       FIG. 7  is a front face view of a snow rake rod for use with the snow lubrication device on the right side of the snowmobile. 
       FIG. 8A  is a front view of a fixing member. 
       FIG. 8B  is a side view of the fixing member shown in  FIG. 8A . 
       FIG. 9A  is a plan view of the snow rake member. 
       FIG. 9B  is a front view of the snow rake member shown in  FIG. 9A . 
       FIG. 9C  is a side view of the snow rake member shown in  FIG. 9A . 
       FIG. 10  is an oblique view of a state in which the snow rake rod rakes up snow and ice on the snow surface. 
       FIG. 11  is a front face view of a snow rake rod for use with the snow lubrication device according to a second embodiment having one or more seal members. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The following detailed description is now directed to certain specific embodiments of the invention. However, the invention can be embodied in a multitude of different systems and methods. In this description, reference is made to the drawings wherein like parts are designated with like numerals throughout. 
     FIG. 1  is a side view of a snowmobile SM comprising a first embodiment of a snow lubrication device  20 .  FIG. 2  is a plan view of the snowmobile SM shown in  FIG. 1  having a vehicle body  10 . The snowmobile SM further comprises a windshield  11  located on the upper front part of the vehicle body  10  for averting wind. Handlebars  12  are located rearward of the windshield  11  and used to operate the snowmobile SM. A seat  13  for a rider is provided on a rear upper part of the vehicle body  10 . 
   Drive wheels (not shown) comprising sprockets are located on both sides of the front part of the vehicle body  10 . Rear wheels  14  are provided on both sides of the rear part of the vehicle body  10 . A track belt  15  is routed around the drive wheels and the rear wheels  14 . The track belt  15  has an outer circumferential surface with projections for engaging with the snow surface. As illustrated in  FIG. 1 , slide rails  16 , free wheels  17   a,    17   b,  etc. are located on a lower portion of the inside of the circumferential surface of the track belt  15 . 
   The slide rails  16 , free wheels  17   a,    17   b,  etc. press the circulating track belt  15  against the snow surface. As a result, the track belt  15  circulates as the projections located on the underside of the track belt  15  engage with the snow surface to cause the snowmobile SM to move forward. Front suspensions  18  are connected to the handlebars  12  on both sides of the vehicle body  10 . For ease of explanation, members of the left front suspension  18  have the same reference numerals as members of the right front suspension  18 . 
   The front suspensions  18  comprise dampers  18   a  on both left and right sides of the vehicle body  10 . Connecting rods  18   c  on both left and right sides connect to the dampers  18   a  through front suspension arms  18   b  and extend below the vehicle body  10 . Corresponding skis  19  for steering are connected to the lower ends of the connecting rods  18   c.  The shapes of the respective members of the left and right front suspensions  18  and the steering skis  19  have left-right symmetry. 
     FIG. 3  is an enlarged front side view of the snowmobile SM and snow lubrication device  20 .  FIG. 4  is a plan view of the snowmobile SM from  FIG. 3 . The front suspension  18  also comprises, as shown in  FIGS. 3 and 4 , an arm part  18   d  for turning the connecting rod  18   c  about its axis. The arm part  18   d  moves back and forth according to the operation of the handlebars  12 . With the back-and-forth motion, the steering ski  19  turns left and right. The steering ski  19  is connected to the connecting rod  18   c  through a support shaft  19   a  connected to the lower end of the connecting rod  18   c.  The steering ski  19  comprises a main part  19   b  in contact with the snow surface and a grip part  19   c.  The grip part  19   c  allows the steering ski  19  to be gripped by hand. 
   The snow lubrication device  20  is in the vicinity of each arm part  18   d  of the vehicle body  10 . The snow lubrication device  20  comprises two fixing arms  21 , each extending from a position slightly behind the arm part  18   d  of the vehicle body  10  obliquely in a downward and forward direction. The snow lubrication device  20  further comprises two snow rake rods  22 ,  22   a  (See  FIG. 7  for  22   a ) fixed to the fixing arms  21  on the sides of the snowmobile SM.  FIG. 5  is a front face view of the snow rake rod  22  for a left side of the vehicle body  10 .  FIG. 6  is a side face view of the snow rake rod  22  from  FIG. 5 , partially in section.  FIG. 7  is a front face view of the snow rake rod  22   a  for a right side of the vehicle body  10 . The snow rake rods  22 ,  22   a  are preferably used as a set on the snow lubrication device  20 . Of course the snow lubrication device  20  could employ a single fixing arm  21  and single snow rake rod  22 , but preferably employs two fixing arms and snow rake rods for both sides of the snowmobile. 
   As illustrated in  FIG. 3 , the fixing arm  21  may be made of a plate-shaped rod member having one or more fixing holes  21   a  along its length. The one or more fixing holes  21  a allow attachment of the snow rake rod  22  at multiple positions. 
   As illustrated in  FIG. 5 , the snow rake rod  22  comprises an elastic rod-shaped member  23 , a fixing member  24  fixed to one end of the rod-shaped member  23  and a snow rake member  25  attached to the other end of the rod-shaped member  23 . A cylindrical fixing member  26  fixes the snow rake member  25  to the rod-shaped member  23 . The rod-shaped member  23  comprises a core member  23   a  made from a wire covered with a plastic cover  23   b.  The core member  23   a  may be made from a metal iron wire or any other suitable, elastic material. In certain embodiments, the rod-shaped member  23  has an approximate length of 250 mm and a diameter of 8 mm. 
     FIG. 8A  is a front view of the fixing member  24 .  FIG. 8B  is a side view of the fixing member  24  shown in  FIG. 8A . The fixing member  24  is preferably made of metal and comprises a fixing part  24   a  fixed to the fixing arm  21 , and a cylindrical part  24   b  fixed to the rod-shaped member  23 . 
   The fixing part  24   a  has a generally oval shape with an attachment hole  24   c  extending therethrough. The attachment hole  24   c  is offset from the center of the fixing part  24   a  in a distal direction towards the fixing arm  21 . The cylindrical part  24   b  has a generally cylindrical shape. The rounded end of the cylindrical part  24   b,  as illustrated in  FIG. 8A , is connected to the fixing part  24   a.  As illustrated in  FIG. 8B , a surface of the fixing part  24   a  is flush with and coupled to a back side surface of the cylindrical part  24   b.  As illustrated in  FIG. 5 , the rod-shaped member  23  and the fixing part  24   a  are fixed together by inserting one end of the rod-shaped member  23  into the cylindrical part  24   b.  The cylindrical part  24   b  is clamped around the inserted end using a crimping process. 
     FIG. 9A  is a plan view of the snow rake member  25 .  FIG. 9B  is a front view of the snow rake member  25  shown in  FIG. 9A .  FIG. 9C  is a side view of the snow rake member  25 . In certain embodiments, the snow rake member  25  comprises cemented carbide. As shown in  FIG. 5  and  FIGS. 9A-9C , a root end part  25   a  is fixed to an end of the rod-shaped member  23 . A front-end side of the root end part  25   a  is fixed to a blade part  25   b.    
   The thickness or horizontal width shown in  FIG. 9A  of the root end part  25   a  is constant. The thickness of the blade part  25   b  decreases near the end of the blade part  25   b.  The width or vertical width shown in  FIG. 9B  is smaller at the root end part  25   a  and increases from the root end part  25   a  side and toward the front-end side. Both side surfaces are formed with irregular parts  25   c  having a wavy irregular shape along a longitudinal direction. Both side surfaces intersect at right angles relative to the width direction of the root end part  25   a.  The blade part  25   b  is shaped to curve from the root end part  25   a  side toward the front-end side. 
   As illustrated in  FIG. 5 , the cylindrical fixing member  26  has a cylindrical shape. In certain embodiments, the cylindrical fixing member  26  is made of metal. The end of the rod-shaped member  23  is inserted into the end of the member  26 . The root end part  25   a  of the snow rake member  25  is inserted into the other end of the member  26  and clamped by a crimping process to fix the rod-shaped member  23  to the snow rake member  25 . A gap between the root end part  25   a  and the cylindrical fixing member  26  is filled with adhesive or other filler agent. The filler agent and the irregular parts  25   c  formed on the root end part  25   a  firmly fix the snow rake member  25  to the rod-shaped member  23  through the cylindrical fixing member  26 . 
   The snow rake rod  22   a  illustrated in  FIG. 7  is the same as the snow rake rod  22  illustrated in  FIG. 5  except that the direction of curvature for the snow rake member  25  of the snow rake rod  22   a  is opposite to the direction of curvature for the snow rake member  25  of the snow rake rod  22 . For ease of explanation, corresponding parts for the left and right sides of the snow mobile SM have the same reference numerals. The snow rake rods  22  and  22   a  described above are fixed to the corresponding fixing arms  21  on the vehicle body  10  through bolts  27  and nuts or through other suitable fasteners. The snow rake rods  22  and  22   a  are attached by first aligning the attachment holes  24   c  of the snow rake rods  22  and  22   a  with one of the fixing holes  21   a  of the fixing arms  21 . The bolts  27  are inserted into both holes. The nuts are then attached to the bolts  27 . 
   A method of operation is described below. First, a switch located in the vicinity of the handlebars  12  is turned on. The switch starts the engine which drives the snowmobile SM. A throttle lever on the handlebar  12  controls the engine. 
     FIG. 10  is an oblique view of a state in which the snow rake rod  22   a  (See  FIG. 7 ) on the right side of the vehicle body  10  rakes up snow and ice on the snow surface. This same description applies equally to the snow rake rod  22  on the left side of the vehicle body  10 . The snow rake rod  22   a  deflects rearward as the blade part  25   b  of the snow rake rod  22   a  comes into contact with the snow surface. The blade part  25   b  rakes up snow and ice on the snow surface and scatters the snow rearward. The scattered snow adheres to the inner surface of the track belt  15  and finds its way into the gap between the track belt  15  and the slide rail  16 , and into the gap between the track belt  15  and the drive wheel. 
   The scattered snow located in the gaps between the track belt  15  and the slide rail  16  and between the track belt  15  and the drive wheel provides lubrication. The lubricated track belt  15  improves the operation of the snowmobile SM. Even if the lower part of the snow rake rod  22   a  strikes a stone or the like, the elasticity of the rod-shaped member  23  allows the snow rake rod  22   a  to deflect further rearward. Even if the snow rake rod  22   a  strikes a stone or the like, the impact does not adversely affect operation of the snowmobile SM. When the snowmobile SM is made to run in reverse, the snow rake rod  22   a  is free to deflect towards the front of the vehicle body  10 . Accordingly, the snow rake rod  22   a  does not hinder operation of the snowmobile SM in forward or reverse directions. 
   As described above, the rod-shaped member  23  is fixed to the fixing member  24  by crimping one end of the rod-shaped member  23  in the cylindrical part  24   b  of the fixing member  24 . The rod-shaped member  23  is firmly fixed to the fixing member  24  to prevent the rod-shaped member  23  from dislodging from the fixing member  24 . Further, since the root end part  25   a  of the snow rake member  25  is thinner than the end part of the rod-shaped member  23 , the snow rake member  25  may have a small size and be light in weight. 
   As illustrated in  FIG. 5 , the rod-shaped member  23  and the snow rake member  25  may be fixed together by abutting the end of the root end part  25   a  of the snow rake member  25  against the end of the rod-shaped member  23 . The adjacent ends are fitted within the cylindrical fixing member  26  and clamped using a crimping process. Further, both surfaces of the root end part  25   a  that are likely to experience shock from the snow surface or the like are formed with the irregular parts  25   c.  The gap between the root end part  25   a  and the cylindrical fixing member  26  is filled with adhesive. Therefore, the snow rake member  25  is firmly fixed to the rod-shaped member  23 . Further, by covering the outer circumference of the core member  23   a  with a plastic cover  23   b,  the core member  23   a  is inhibited from developing rust. 
     FIG. 11  is a front face view of a snow rake rod  32  for use with the snow lubrication device according to a second embodiment. The snow rake rod  32  is the same as the snow rake rod  22  described with reference to  FIG. 5  except that the snow rake rod  32  comprises seal members  38 ,  39 . For ease of explanation, the same parts are provided with the same reference numerals without repeating their descriptions. Like the embodiment described with reference to  FIG. 5 , the embodiment illustrated in  FIG. 11  includes a pair of snow rake members  25  curving in opposite directions. The seal member  38  may be made of plastic and covers the joint between a rod-shaped part  23  and a fixing member  24 . The seal member  39  may be made of plastic and covers the joint between the rod-shaped part  23  and a cylindrical fixing member  26 . 
   The seal members  38 ,  39  inhibit water from finding its way into the joints between the rod-shaped member  23  and the fixing member  24  and into the joint between the rod-shaped member  23  and the cylindrical fixing member  26 . The seal members  38 ,  39  inhibit water from seeping into the plastic cover  23   b  of the rod-shaped member  23  and inhibit the core member  23   a  inside the cover from developing rust. Further, covering the joint between the rod-shaped member  23  and the fixing member  24  with the seal member  38 , and covering the joint between the rod-shaped member  23  and the cylindrical fixing member  26  with the seal member  39 , improves the external appearance of the snow rake rod  32 . The snow rake rod  32  performs the same function and effect of lubrication as the snow rake rod  22  described with reference to the first embodiment. 
   This invention is not limited to the above-described embodiments but may be appropriately modified and implemented accordingly. For example, while the plastic cover  23   b  and the seal members  38 ,  39  are made of plastic in certain embodiments, it is possible to make them from other materials. Further, in embodiments where the core member  23   a  of the rod-shaped member  23  is made of a rust-free material such as stainless steel, the plastic cover  23   b  may be omitted. Furthermore, shapes and materials of other parts of the snow lubrication device  20  related to this invention may be appropriately modified within the technical scope of this invention. 
   While the above detailed description has shown, described, and pointed out novel features of the invention as applied to various embodiments, it will be understood that various omissions, substitutions, and changes in the form and details of the device or process illustrated may be made by those skilled in the art without departing from the spirit of the invention. The scope of the invention is indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Technology Classification (CPC): 8