Patent Abstract:
A snow vehicle having a combined brake and clutch handle is herein disclosed. Further, the snow vehicle can include a controller for managing operation of the snow vehicle, including shifting and engine management regiments, which can be selected by the operator depending upon operator preferences. Additionally, the snow vehicle can include an engine cooling heat exchanger for cooling liquid which is circulated through the engine.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of and priority to U.S. Provisional Application No. 62/298,438, filed Feb. 22, 2016, titled “Snow Vehicle,” having Attorney Docket Number S.2C.1051-US01, and having inventors: Rick Allen Warne, Andrew Jon Ellsworth, Kevin David Thompson, Cord Miller Christensen, and Andrew Beavis, the contents of which are herein incorporated by reference. This application further claims the benefit of and priority to U.S. Provisional Application No. 62/323,428, filed Apr. 15, 2016, titled “Snow Vehicle,” having Attorney Docket Number S.2C.1051-US02, and having inventors: Rick Allen Warne, Andrew Jon Ellsworth, Kevin David Thompson, Cord Miller Christensen, and Andrew Beavis, the contents of which are herein incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    Various types of snow vehicles are known in the art. Such snow vehicles suffer from a number of inadequacies, however. For example, some such vehicles can be difficult to shift. Further, some such snow vehicles suffer from vehicle architecture that is not conducive to operation in certain terrains and performance may be hindered. 
       SUMMARY 
       [0003]    In light of the foregoing, there remains a need to overcome shortcomings of existing vehicle designs and components. By way of example, in some embodiments, a snow vehicle includes an endless track, a frame, an engine, and a transmission. In some embodiments, the engine and transmission are attached to the frame and the engine is drivingly coupled to the endless track via the transmission. In some embodiments, the vehicle further includes a clutch, and at least a portion of the clutch is rotatably coupled to the transmission. In some embodiments, the vehicle further includes a brake actuator and handlebars. In some embodiments, a hand lever is attached to the handlebars. The hand lever has a first position, a second position, and a third position. In some embodiments, movement of the hand lever from the first position to the second position actuates the clutch and movement of the hand lever from the second position to the third position actuates the brake actuator. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in difference views. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document. 
           [0005]      FIG. 1  shows an embodiment of a snow vehicle. 
           [0006]      FIG. 2  shows an embodiment of a snow vehicle, including an actuator assembly. 
           [0007]      FIG. 3  shows an embodiment of a snow vehicle, including an actuator assembly. 
           [0008]      FIGS. 4 and 5  show embodiments of portions of actuator assemblies. 
           [0009]      FIG. 6  shows a 3-dimensional view of a portion of an actuator assembly. 
           [0010]      FIG. 7  shows a top view of a portion of an actuator assembly. 
           [0011]      FIG. 8  shows a partially exploded view of a portion of an actuator assembly. 
           [0012]      FIG. 9  shows a side view of an embodiment of the actuator assembly of  FIG. 7 . 
           [0013]      FIG. 10  shows a side view of an embodiment of the actuator assembly of  FIG. 7 . 
           [0014]      FIG. 11  shows a top view of an embodiment of an actuator assembly. 
           [0015]      FIG. 12  shows an embodiment of a heat exchanger. 
           [0016]      FIG. 13  shows an embodiment of a snow vehicle having a cooling system. 
           [0017]      FIG. 14  shows a partial view of an inside of an embodiment of a track  16 . 
           [0018]      FIGS. 15A-15C  show view of an embodiment of a track clip. 
           [0019]      FIG. 16  shows a front view of another embodiment of a track clip. 
           [0020]      FIG. 17  shows an embodiment of a snow vehicle, including an actuator assembly. 
           [0021]      FIG. 18  shows a portion of an embodiment of the actuator assembly of  FIG. 17 . 
           [0022]      FIG. 19  shows a side view of an embodiment of an actuator assembly of  FIG. 17 . 
           [0023]      FIG. 20  shows a partial schematic of a hydraulic system. 
           [0024]      FIG. 21  shows an embodiment of a skid frame assembly. 
           [0025]      FIG. 22  shows a side view of the embodiment of the skid frame assembly of  FIG. 21 . 
           [0026]      FIG. 23  shows a cross sectional view of the embodiment of the skid frame assembly of  FIG. 22 . 
           [0027]      FIG. 24  shows an embodiment of a tunnel and skid frame assembly. 
           [0028]      FIG. 25  shows a side view of the embodiment of the tunnel and skid frame assembly of  FIG. 24 . 
           [0029]      FIGS. 26 and 27  show schematics of controller configurations for operation of the snow vehicle  10 . 
           [0030]      FIG. 28  shows an embodiment of a mode selector for selecting various modes of operation. 
           [0031]      FIG. 29  shows an embodiment of a toggle shifter mounted to the handlebars of a snow vehicle  10 . 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    With regard to  FIG. 1 , a snow vehicle  10  comprises a main frame  12 , a prime mover  14  (such as an engine or motor) and a track  16 . The snow vehicle  10  further comprises handlebars  18  and a front suspension assembly  20 . In some embodiments, the front suspension assembly  20  comprises a fork  21 ; in some embodiments, however, the front suspension assembly  20  comprises an A-arm suspension, or any other suitable type of suspension. 
         [0033]    In some embodiments, the snow vehicle  10  further comprises at least one front ski  22  and at least one upright  24 . As illustrated in  FIG. 1 , the upright  24  attaches the front ski  22  to the fork  21  and can include a pin  25  (e.g., bolt), permitting the ski  22  to pivot relative to the upright  24 . In some embodiments, the snow vehicle  10  can comprise a plurality of skis  22 , for example which are spaced laterally from one another. The skis  22  can be attached to the same upright  24  or different uprights. In some embodiments, for example where two skis are used in conjunction with two shocks  26  of a fork  21 , each ski  22  can move along the direction of the shock  26  independently of the other ski. Stated differently, each shock  26  is coupled to one of the skis  22 . 
         [0034]    In some embodiments, the prime mover  14  is a 4-stroke engine. The prime mover  14  can also be a 2-stroke engine, an electric motor, or fuel cell, for example. Where an engine is used, it can be naturally aspirated or it can have a power adder, such as a supercharager (e.g., belt-driven, gear-driven) or turbocharger. The engine can include a carburetor or it can be fuel injected. 
         [0035]    The prime mover  14  is rotatably linked to a transmission  28  via a clutch  30  ( FIG. 2 ) such that actuation of the clutch  30  selectively engages the transmission  28  to the prime mover  14 . In some embodiments, the snow vehicle  10  includes an actuator assembly  29 . In some embodiments, the clutch  30  is actuated by the operator via the actuator assembly  29 , which includes a lever  32 . In some embodiments, the lever  32  is attached to the handlebars  18 . As shown in  FIG. 2 , for example, the lever  32  is attached to the left side of the handlebars  18  such that the lever  32  can be actuated with an operator&#39;s left hand, with one or more of the operator&#39;s fingers. As further shown in  FIG. 2 , movement of the lever  32  actuates the clutch  30  via a clutch actuator  34 . The clutch actuator  34  can comprise a slave cylinder  36 , for example if the clutch  30  is a hydraulic clutch. In some embodiments, the clutch actuator  34  comprises a mechanical linkage, for example a braided wire cable or push-pull cable that is attached to the lever  32 . 
         [0036]    In some embodiments, the clutch  30  is a dirt bike style clutch, for example having one or more clutch plates, friction plate, pressure plate, throw out bearing, clutch release bearing, and/or springs. 
         [0037]    As further shown in  FIG. 2 , in some embodiments, the lever  32  of the actuator assembly  29  is further linked to a brake actuator  38  (e.g., a brake caliper). The brake actuator  38  can be a hydraulic actuator or it can be actuated via a mechanical linkage, such as a brake cable that is connected to the lever  32 . As illustrated in  FIG. 2 , in some embodiments, the brake actuator  38  is located exteriorly of the track  16 . As shown in  FIG. 3 , however, in some embodiments, the actuator  38  is located interiorly of the track  16 . As further shown in  FIG. 3 , a brake disc  40  is coaxial with a track drive member  42  (e.g., sprocket). In the embodiment of  FIG. 2 , however, it is evident that the brake disc  40  is located on an axis that is not coaxial with the axis of drive member  42 . In at least some embodiments, the snow vehicle  10  further includes at least one drive belt or drive chain  44  to transmit power from the transmission to the drive axle  46  and drive member  42 . 
         [0038]    With further regard to  FIG. 2 , in some embodiments, the snow vehicle  10  has a throttle actuator  48 . The throttle actuator  48  can comprises a thumb lever, as in  FIG. 2 , a twist handle, as in  FIG. 3 , or any other suitable type of actuator. Further, the throttle actuator can be linked directly the engine (e.g., throttle body) or it can be routed to an ETC (electronic throttle control), for example via a throttle position sensor. In some embodiments, the snow vehicle  10  includes an accelerometer  50  to measure acceleration or deceleration of the snow vehicle. In turn, the accelerometer  50  can be in electronic communication with the electronic throttle control to control track spin (e.g., “traction control”). Stated differently, if the accelerometer  50  detects that the acceleration of the snow vehicle  10  does not match the speed of track (or engine, transmission, or drive axle RPM), the ETC can limit the power output of the engine  14 . 
         [0039]    In some embodiments, an ETC can limit the power output of the engine  14 , and limit track spin, by way of a controller (e.g., engine control unit (ECU)) which is programmed to compare the rate of increase of RPM (engine and/or transmission and/or drive axle) to a predetermined value. In the event that the rate of increase of RPM exceeds the predetermined value, the controller knows that the track  16  is spinning and can reduce power output of the engine, for example via the ETC, to reduce or prevent track spin. In some embodiments, the snow vehicle  10 , has a switch  54  (button, toggle, or dial, see  FIG. 4 ) to enable or disable the track spin limiting control. 
         [0040]    Turning to  FIG. 4 , in some embodiments, the combined clutch/brake lever  32  utilizes a hydraulic clutch master cylinder  52  and a mechanical brake cable or linkage  56 . As shown in  FIG. 5 , in some embodiments, the combined clutch/brake lever  32  utilizes a mechanical clutch cable (or linkage)  58  and a mechanical brake cable (or linkage)  56 . In both  FIGS. 4 and 5 , the combined clutch/brake lever  32  rotates about a single pivot axis  60 . Any suitable combination of mechanical and hydraulic arrangements can be utilized. For example, the clutch can be a hydraulic system while the brake is mechanical; the clutch can be mechanical while the brake is hydraulic; both clutch and brake are mechanical; or both clutch and brake are hydraulic, as shown in  FIG. 6 . 
         [0041]    As further shown in  FIG. 6 , in some embodiments, the combined clutch/brake lever  32  is pivotably attached to a main body  62  via pivot axis  60 . In some embodiments, the main body  62  comprises at least one fluid housing  64 . The fluid housing  64  has a cover  66 . The fluid housing  64  can be filled with hydraulic fluid, which is used to actuate the clutch and/or brake. In some embodiments, the clutch system and brake system share a common hydraulic reservoir. In some embodiments, however, two fluid housings  64  can be used, one each for the brake system and clutch system. Further still, in some embodiments, a single fluid housing  64  having two compartments within the fluid housing is utilized. The two compartments segregate hydraulic fluid between the respective systems. In some embodiments, the actuator assembly  29  comprises a single master cylinder and two slave cylinders; one slave cylinder for the brake actuator and one slave cylinder for the clutch actuator. 
         [0042]    In some embodiments, the actuator assembly  29  includes a parking brake lock  68 . The parking brake lock  68  which can be rotated about axis  70  (see  FIG. 7 ) to lock the lever  32  against the main body  62 , thereby engaging the brake actuator  38  ( FIGS. 2, 3 ). 
         [0043]    In some embodiments, the actuator assembly  29  comprises a mechanical emergency brake which can, optionally, be in addition to the hydraulic brake system. As shown in  FIG. 6 , for example, an emergency brake cable  72  can be affixed to the actuator assembly and it can be selectively engaged. In some embodiments, the mechanical emergency brake can be independent of the hydraulic brake system, for example. 
         [0044]    Turning to  FIG. 8 , a partially exploded view of a portion of the actuator assembly  29  is shown. As shown, in some embodiments, the lever  32  comprises a first contact surface  74  and a second contact surface  76 . The first contact surface  74  is located adjacent to the first piston  78  (shown via hidden lines) such that when the operator moves the lever  32  toward the handlebars  18 , the first contact surface  74  moves the first piston  78  in the direction of arrow  80 . Similarly, the second contact  76  is located adjacent to the second piston  82  (shown via hidden lines) such that when the operator moves the lever  32  toward the handlebars  18 , the second contact surface  76  moves the second piston  82  in the direction of arrow  84 . 
         [0045]    In some embodiments, the first piston  78  operates the hydraulic system of the clutch actuator  34  while the second piston  82  operates the hydraulic system of the brake actuator  38 . In some embodiments, the first piston  78  is engaged by the first surface  74  before the second piston  82  is engaged by the second surface  76  as the operator moves the lever  32  toward the handlebars  18 . Functionally, therefore, in some embodiments, the clutch  30  is disengaged from the transmission  28  prior to application of the brakes when the operator is trying to slow or stop the snow vehicle  10 . Moreover, when the operator wishes to engage the clutch  30 , the brakes have been released. 
         [0046]    With regard to  FIG. 11 , in some embodiments, the lever  32  has a first position  86 , a second position  88 , and a third position  90 . When the lever  32  is in the first position  86 , the brake is disengaged (the brake disc  40  rotates freely) and the clutch  30  is engaged to the transmission  28  such that power can be transferred from the prime mover  14  to the track  16 . When the lever  32  is in the second position  88 , the clutch  30  is disengaged from the transmission  28  and the brake is disengaged. Finally, when the lever  32  is in the third position  90 , the clutch  30  is disengaged from the transmission and the brake is engaged (the brake disc  40  no longer rotates freely). As will be appreciated, both the clutch actuator  34  and brake actuator  38  have degrees of actuation, such that the clutch  30  can be smoothly engaged and the brake can be applied as desired (e.g., minor braking or major braking). 
         [0047]    Returning to  FIG. 7 , in some embodiments, when the lever  32  is in the first position, the first surface  74  is located more closely to the first piston  78  than the second surface  76  is located relative to the second piston  82 . Stated differently, when the lever  32  is in the first position  86 , the first surface  74  is separated from the first piston  78  by a distance A, where A is ≧0, and when the lever  32  is in the first position  86 , the second surface  76  is separated from the second piston  82  by a distance B, wherein B is &gt;A. Thus, in the first position  86 , B&gt;A≧0. It will be appreciated, that any other suitable arrangement can also be utilized. For example, where the first piston  86  and/or second piston  82  have portions extending toward the respective surfaces ( 74 ,  76 ) of the lever  32 , the distances A and B can be measured with respect to extending portions, which may be intermediate of the respective piston and surface. Further, the first and second pistons  78 ,  82  can have protective covers extending thereover. 
         [0048]    Returning to  FIG. 8 , in some embodiments, the first piston  78  can be in communication with a first hydraulic line  92  and the second piston  82  can be in communication with the second hydraulic line  94 . In some embodiments, the first hydraulic line  92  is connected to the clutch actuator  34  and the second hydraulic line  94  is connected to the brake actuator  38 . 
         [0049]    As further shown in  FIGS. 8 and 9 , in some embodiments, the actuator assembly  29  has hydraulic ports  96 ,  98  to connect to the hydraulic lines (e.g.,  92 ,  94 ). In some embodiments, the lever  32  is canted relative to the horizontal by an angle Θ ( FIG. 10 ). This arrangement may provide improved ergonomics as compared to a lever  32  that moves horizontally. 
         [0050]    In some embodiments, the actuator assembly  29  has a detent  112 , which can be located on the lever  32  or the main body  62  so that the operator can feel when the lever is being moved from the first position  86  to the second position  88  or from the third position  90  to the second position  88 . The detent  112  can interact with a ball (e.g., spherical bearing such as a ball bearing) with a spring (e.g., coil spring) to provide the operator with feedback about the position of the lever  32 . In some embodiments, the lever  32  is formed from a single piece of material, such as aluminum. 
         [0051]    Returning to  FIG. 1 , in some embodiments, the snow vehicle  10  further comprises a foot brake  100 , which can be used in conjunction with or in lieu of the lever  32  to actuate the brake actuator  38 . Although the foot brake  100  is shown on the left hand side, it will be appreciated that the foot brake  100  can be located on either side of the snow vehicle  10 . 
         [0052]    In some embodiments, the snow vehicle  10  comprises a rear brake light  102 , hand warmers, and/or thumb warmers, and a front headlight  103 . 
         [0053]    In some embodiments, the snow vehicle  10  has a front shroud  104 , which can shield the engine and componentry from snow. It can also help shield the operator from terrain and cold air passing by the operator as the snow vehicle is ridden. 
         [0054]    In some embodiments, the snow vehicle  10  comprises a heat exchanger  106 . The heat exchanger  106  can be used in lieu of or in addition to a radiator to cool the engine. In some embodiments, the snow vehicle  10  comprises a track frame  108  to which the heat exchanger  106  is attached. The heat exchange  106  can extend along the entire distance of track frame  108  or it can extend along only a portion of the track frame  108 . In some embodiments, the heat exchanger  106  is located above the track  16 . The heat exchanger  106  can be formed from any suitable material, such as aluminum. Further, the heat exchanger  106  can include a plurality of fins  110  (see  FIG. 12 ) to dissipate heat from the coolant flowing through the heat exchanger  106 . 
         [0055]    In some embodiments, the snow vehicle  10  further includes a cooling system  114  having a coolant tank  116 , shown in  FIG. 13 , a cap  118 , and coolant lines  120  extending between the engine, coolant tank  116 , and heat exchanger  116 . In some examples, at least some of the coolant lines  120  extend outside of the track frame  108 . In some examples, however, at least some of the coolant lines  120  extend interiorly to the track frame  108 . Further, in some examples, the coolant tank is located below the operator&#39;s seat  122  but above the heat exchanger  106 . In some examples, the coolant tank  116  is located above the top of the track frame  108 . In some examples, the coolant tank is located above the operator&#39;s seat  122 . 
         [0056]    Returning to  FIG. 12 , the heat exchanger  106  has an intake fitting  124  and a return fitting  126 . The fittings  124 ,  126  can be arranged in any suitable configuration. 
         [0057]    In some embodiments, the heat exchanger  106  comprises a portion of the track frame  108  and provides stiffness to the track frame  108 . Stated differently, in some embodiments, the heat exchanger  106  can also serve as a structural member, thereby reducing the amount of structure of the track frame  108  and providing a lighter snow vehicle  10 . 
         [0058]    The snow vehicle  10  further comprises foot rests  128  (see  FIG. 13 ), which can be located on one or both sides of the snow vehicle  10 . Moreover, in some embodiments, the track frame  108  is attached to the main frame  12  with a swing arm having a coil spring. Or, the track frame  108  can be attached to the main frame  12  via a rigid strut. Or, the track frame  108  can be attached to the main frame via a torsion spring, an elastomeric member, or in any other suitable configuration. Further still, the track frame  108  can have internal suspension members  130 , which can be used independently or in conjunction with suspension between the track frame  108  and the main frame  12 . In some embodiments, the snow vehicle  10  has a rear flap  132  for deflecting snow; in some embodiments, the snow vehicle  10  has a lift handle  134 , which can be used to lift a rear end of the snow vehicle  10 . 
         [0059]    With regard to  FIG. 14 , an interior of a portion of a track  16  is shown. The track  16  has a plurality of windows  136  and a plurality of track clips  138 . As further shown in  FIGS. 15A-C , in some embodiments, the track clips  138  have a protruding center portion  140  which extends inwardly toward the interior of the track  16 . In some embodiments, the track clips  138  and windows  136  are located along the centerline of the track  16 . 
         [0060]    In some embodiments, as show in  FIG. 16 , the track clips  138  protruding portions  142  at opposing ends of the track clip  138 . Such track clips  138 , whether having protruding portions  142  at opposing ends of the track clip  138  or a protruding center portion  140  are believed to reduce the possibility of a track derailment, especially in conditions where the snow vehicle  10  is traversing a path perpendicular to an incline (e.g., “side hilling”). 
         [0061]    Turning to  FIGS. 17-20 , in some embodiments, the snow vehicle  10  includes an actuator assembly  29 . In some embodiments, the actuator assembly  29  includes a first lever  32   a  and a second lever  32   b.  In some embodiments, the first lever  32   a  actuates both the clutch actuator  34  and the brake actuator  38 , as previously discussed herein. As shown in  FIG. 17 , in some embodiments, the second lever  32   b  actuates the brake actuator  38 . The second lever  32   b  may not be linked to the clutch actuator  34  such that upon squeezing the second lever  32   b,  the brake actuator  38  is actuated but the clutch actuator  34  is not actuated, regardless of how far the second lever  32   b  is squeezed. Stated differently, in some embodiments, the second lever  32   b  is tied only to the brake actuator  38  and is not tied to the clutch actuator  34 . 
         [0062]    As further shown in  FIG. 17 , in some embodiments, the snow vehicle  10  has a first master cylinder  152  and a second master cylinder  154 . The first master cylinder  152  and the second master cylinder  154  can include hydraulic fluid common to both master cylinders  152 ,  154 . In some embodiments, the first master cylinder  152  includes two pistons (e.g.,  78 ,  82 ) as previously described with respect to  FIG. 8 . Further, in some embodiments, the second master cylinder  154  has a single piston which is fluidly connected to a third hydraulic line  156 . In turn, and with regard to  FIGS. 18 and 19 , the third hydraulic line  156  fluidly connects the second master cylinder  152  to the second piston  82  ( FIG. 8 ; e.g., brake piston) so as to actuate the brake actuator  38  as the second lever  32   b  is actuated. In this way, the brake actuator  38  can be actuated by either the right hand brake (e.g.,  32   a ) or the left hand brake (e.g.,  32   b ). 
         [0063]    Although shown in  FIGS. 17-19  with a hydraulic system, the levers  32   a  and  32   b  can also be tied to mechanical systems (e.g., cables), as previously discussed. 
         [0064]    With regard to  FIG. 19 , in some embodiments, the third hydraulic line  156  is coupled to the main body  62 . In some embodiments, however, the third hydraulic line  156  can be coupled to a second hydraulic line  94 , as shown in  FIG. 20 , for example with a fitting  158  (e.g., Y-connector) in the hydraulic line. In this way, the third hydraulic line  156  intersects the second hydraulic line  94  outside or downstream of the main body  62 . As will be appreciated, other arrangements are possible. 
         [0065]    In some embodiments, only one of the levers  32   a  or  32   b  has a parking brake lock  68 . In some embodiments, however, both levers  32   a  and  32   b  have a parking brake lock. Further, in some embodiments, actuation of either of the of the levers  32   a  and  32   b  turns on the brake light  102 . Further still, in some embodiments, the snow vehicle  10  comprises a foot brake (discussed previously) that is also tied into the hydraulic system to actuate the brake actuator  38 . In this way, the snow vehicle  10  can have one, two, or three master cylinders, each of which can be actuated to operate the brake actuator  38 . Moreover, upon actuation of the foot brake  100 , the brake light  102  can turn on. 
         [0066]    Turning to  FIGS. 21-23 , in some embodiments, the snow vehicle  10  comprises a skid frame assembly  200 . The skid frame assembly  200  can include a plurality of bogey wheels  202 , which are spaced from and along the length of a skid rail  204 . In some embodiments, the snow vehicle  10  includes a single skid rail  204  which is located along the longitudinal centerline of the snow vehicle  10 , as illustrated for example in  FIGS. 2 and 3 , as the skid rail  204  works in conjunction with the track  16 . In some embodiments, the skid rail  204  comprises a hollow portion  206 , as shown for example in  FIG. 23 . In some embodiments, the skid rail  204  is blow molded, though it can be formed in other ways; for example, the skid rail  204  can be formed from an extrusion, for example of aluminum or plastic. In some embodiments, the snow vehicle  10  utilizes an embodiment of the suspension shown in U.S. Pub. No. 2015/0166143, having inventor Andrew Beavis and application Ser. No. 14/109,760, which is herein incorporated by reference in its entirety. Further, components disclosed in U.S. Pub. No. 2015/0166143 can also be used in conjunction with the snow vehicle  10 . 
         [0067]    In some embodiments, the skid frame assembly  200  includes a slider joint  208 . In some embodiments, the skid frame assembly  200  includes a spring  210  (e.g., torsion spring or coil spring) and a damper  212 . Further, the spring  210  is coupled to an adjuster  214  that can be moved relative to cross beam  216  so that the suspension can be adjusted, for example by providing a greater or lesser degree of pre-tension. 
         [0068]    With regard to  FIG. 23 , in some embodiments, skid frame assembly  200  further includes a wear strip  218  (e.g., Hyfax) which can be replaced and which contacts a portion of the track clips  138  (e.g.,  FIG. 16 ). 
         [0069]    Turning to  FIGS. 24 and 25 , it will be appreciated that the skid frame assembly  200  can also be coupled to a tunnel  220 . The tunnel  220  can be formed from any suitable material, for example aluminum or plastic. Further, the skid frame assembly  200  can be used with any desired variety of snowmobile (e.g., 2017 Arctic Cat® M) or “snow bike”; another suitable snow vehicle is Arctic Cat&#39;s SVX 450. 
         [0070]    With regard to  FIG. 26 , in some embodiments, the transmission  28  utilizes a shift controller  300 . The shift controller  300  can be a separate unit which may be dedicated to controlling functionality of the transmission  28 . In some embodiments, however, the shift controller  300  is combined with the controller  302  (e.g., engine control unit (ECU)); in some embodiments, however, the shift controller  300  and controller (e.g., ECU) are separate. In some embodiments, the shift controller  300  is in communication with the controller  302  (e.g., ECU) such that the shift controller  300  and controller  300  share information which one another about status of various systems of the snow vehicle  10 . 
         [0071]    As further shown in  FIG. 26 , in some embodiments, the shift controller  300  can receive information from one or more onboard sources. For example, in some embodiments, a mode selector  304  can instruct the shift controller  300 , for example, to operate in manual or automatic modes, as discussed in greater detail below. Further, the controller  302  (e.g., ECU) can receive inputs from one or more sources, such as vehicle speed sensor  306  (e.g., track speed sensor), engine speed sensor  308 , engine load calculator  310 , and shift controller  300 . In turn, the controller  302  can, in response to one or more conditions (e.g., vehicle speed sensor  306 , engine speed sensor  308 , etc.), the controller  302  can control, in combination with shift controller  300 , one or more vehicle functionalities, such as shift actuator  312 , clutch actuator  314 , throttle body position  316 , ignition timing  318 , and fuel injection  320  (e.g., fuel map). In some embodiments, the shift controller  300  signals the shift actuator  312  and clutch actuator  314  to shift gears of the vehicle based on information gathered from one or more of the various input sources. By way of example, in some embodiments, if the snow vehicle  10  is in a low range forward gear (e.g., first gear) and the ECU determines that the RPM is above a threshold level and the load is below a threshold level, the shift controller  300  will instruct the clutch actuator  314  to actuate the clutch. During actuation of the clutch, in order to prevent over-revving of the engine, the ECU will instruct the fuel injection system to reduce fuel to the engine and/or change when, during the engine cycle, fuel is input into the cylinder. As the clutch is actuated, the shift controller  300  will instruct the shift actuator  312  to shift to the next desired gear (e.g., 2 nd  gear). Thereafter, the shift controller  300  will instruct the clutch actuator  314  to “let out” the clutch and the ECU will instruct the fuel injection system to increase fuel supplied to the engine, or as otherwise called-for by the operator. 
         [0072]    In some embodiments, the shift controller  300  will instruct the clutch actuator  314  to disengage and reengage with every shift. In some embodiments, however, the clutch actuator  314  will only disengage and reengage in some shifts and depending upon shift mode (as discussed in greater detail with respect to  FIG. 28 ). For example, where there transmission is a sequential manual gearbox (SMG), it may not be necessary to disengage/reengage the clutch between some or all gears. Again by way of example, if the mode selector  304  is set to race mode (indicated by race mode light  328  in  FIG. 28 ), shifting between forward gears may be conducted without actuation of the clutch actuator  314 . In other modes, however, the clutch actuator  314  may be utilized upon shifting. Further still, in some embodiments, the clutch actuator  314  may not be present at all. Again, by way of example, where an SMG transmission is utilized, a hand clutch (as discussed previously) can be used to start-off in first gear only and, thereafter, the shift actuator  312  performs shifts without disengaging/reengaging the clutch. Of course, the aforementioned examples are merely that—examples—and the shift controller  300  can perform shifts in any appropriate way. 
         [0073]    With further reference to  FIG. 26 , some of onboard information sources and/or vehicle functionalities (e.g.,  304 ,  306 ,  308 ,  310 ,  312 ,  314 ,  316 ,  318 ,  320 ) can both receive information from the shift controller  300  and send information to the shift controller  300 . For example, in some embodiments, one or both of the clutch actuator  314  and shift actuator  312  receive signals from the shift controller  300  to perform their function and, additionally, send signals to the shift controller  300  (or controller  302 ) to monitor the state of the clutch actuator  314  and/or shift actuator  312 . This bi-directional relationship also be the case for any of the onboard information sources and/or vehicle functionalities. 
         [0074]    Another example of a schematic is shown in  FIG. 27 , illustrating that functionalities and/or onboard information sources can be tied directly with the shift controller (e.g., engine load calculator  310 , engine speed sensor  308 ). The schematic is illustrative, and the controller  302  can be combined with the shift controller  300  such that separate controllers are unnecessary. In some embodiments, the shift controller  300  includes an input from a brake sensor  309 . 
         [0075]    In some embodiments, the clutch actuator  314  is a linear actuator, solenoid, rotary actuator, stepper motor, etc. Further, in some embodiments, the shift actuator  312  is a linear actuator, solenoid, rotary actuator, stepper motor, etc. In some embodiments, the shift actuator  312  is coupled to a shift drum to shift gears. 
         [0076]    Turning to  FIG. 28 , an example of a mode selector  304  is shown. In some embodiments, the mode selector  304  is mounted to the handlebars  18  (shown in  FIG. 1 ) or display area so that it can be easily viewed and operated by the operator of the snow vehicle  10 . Although the mode selector  304  can employ any suitable arrangement of switches and modes, in some embodiments, the model selector includes a mode selector switch  330 . In some embodiments, the mode selector  304  further comprises a shift selector switch  332  and, in some embodiments, a neutral selector switch  334 . The neutral selector switch  334  can be used to instruct the shift controller  300  to place the transmission in neutral. With the shift selector switch  332  the operator can select between an “auto” mode and a “manual” mode. In the auto mode, in some embodiments, the mode selector  304  instructs the shift controller  300  to shift the transmission automatically, for example as discussed previously with regard to  FIGS. 26 and/or 27 . Further, in some embodiments, when the auto mode is selected, the operator can further select between a number of shift modes, for example: Trail, Sport, Hill-climb, and Race. In some embodiments, the mode selector switch  330  can be repeatedly pressed to toggle between modes. Upon selection of the specified shift mode, in some embodiments, a light (e.g., light emitting diode) will signify which mode has been selected (e.g., when Trail mode is selected, the trail mode light  322  is illuminated; when the Sport mode is selected, the sport mode light  324  is illuminated; when Hill-climb mode is selected, the hill-climb mode light  326  is illuminated; when the Race mode is selected, the race mode light  328  is illuminated). While shown with a light associated with each mode, the information can be communicated to the operator in any appropriate way, such as on a gauge display, touchscreen, monitor, etc. Moreover, in some embodiments, the selected shift mode will influence how the shift controller  300  controls shifts and, in some embodiments, throttle response, and even the characteristics of the suspension (soft, stiff). 
         [0077]    In some embodiments, the selected shift mode will direct the shift controller  300  to adjust shift points. By way of example, in the Trail mode, the transmission may shift from a first gear to a second gear at a lower RPM when compared to the Sport mode, in order to stay in a more favorable part of the engine&#39;s power-band. Further, in some embodiments, when in the Sport mode, the transmission may downshift from a higher gear at a higher RPM when compared to the Trail mode, in order to stay in a more favorable part of the engine&#39;s power-band. In some embodiments, the Sport mode will generally be associated with more aggressive driving than the Trail mode. In some embodiments, the Hill-climb mode will have a different shift profile than the Trail, Sport, and Race modes. Further, the Race mode will have a different shift profile than the Trail, Sport, and Hill-climb modes. 
         [0078]    In some embodiments, when operated in the manual mode, the operator will instruct the snow vehicle  10  when to undertake an upshift or downshift, for example via toggle shifter  336  ( FIG. 29 ). In some embodiments, the toggle shifter  336  is mounted to the handlebars, for example on the left side of the handlebars  18  and above or below a portion of the grip. When the operator toggles “UP”, the transmission shifts to the next higher gear and when the operator toggles “DOWN”, the transmission shifts to the next lower gear. In some embodiments, while the operator is instructing the transmission to shift, the instructions are being routed through the shift controller  300  to carry out the operator&#39;s demand and, in some embodiments, prevent damage to components (e.g., where the operator selects a downshift that would over-rev the engine). In some embodiments, the manual mode relies on the shift controller  300 . 
         [0079]    In some embodiments, the shift controller  300  prevents the engine from stalling, for example by disengaging the clutch one the engine RPM drops below a threshold value via the clutch actuator  314 . In some embodiments, an operator can place the snow vehicle  10  in gear (e.g., by toggling DOWN on the toggle shifter  336 ) while holding the first or second lever  32   a ,  32   b,  or both levers. 
         [0080]    In some embodiments, the shift controller  300  automatically downshifts the transmission in order to reduce wear on drivetrain components. In some embodiments, the shift controller  300  downshifts the transmission in the event the shift controller  300  has employed the anti-stalling instructions. For example, in the event the shift controller  300  disengages the clutch due to a sensed stall of the engine, the shift controller  300  can also automatically downshift to the next lowest gear or appropriate gear. In some embodiments, gear range is shown on a gauge display in front of the operator. 
         [0081]    The auto/manual/modes/neutral can all be selected by toggling a single switch. Further, these modes can be combined in any suitable combination of switches, etc., and information can be displayed to the operator in any suitable way.

Technology Classification (CPC): 5