Snowmobile ski assembly

A snowmobile ski assembly has a ski having a bottom. At least one wheel is rotatably connected to the ski and a lower portion of the at least one wheel extends below the bottom of the ski. A ski runner operatively connected to the ski is movable between a first position and a second position. A bottom of the ski runner is above the lower portion of the at least one wheel when the ski runner is in the first position and the bottom of the ski runner is below the lower portion of the at least one wheel when the ski runner is in the second position.

TECHNICAL FIELD

The present technology relates to snowmobile ski assemblies.

BACKGROUND

Snowmobiles skis are typically provided with keels extending below to aid in steering of the snowmobile. For instance, deeper keels are desired for aggressive riding of the snowmobile or when the riding surface is covered with soft-packed snow, while shallower keels are desired when the riding surface is covered with hard-packed snow or ice. To help prevent wear of the keels of the skis and to assist in steering on hard-packed snow or ice, metallic ski runners are usually provided against the bottom of the keels. Some snowmobile ski assemblies provide adjustable ski runners where the height of the ski runners can be selected depending on the conditions of the riding surface.

However, when the snowmobile is ridden on a surface that is not covered with snow or ice, such as asphalt, concrete or wood, a portion of the weight of the snowmobile is applied to the keel and/or the ski runner of the skis, thus making the steering of the snowmobile less responsive for the rider. Riding on such surfaces may prematurely wear the bottom surface of the keel and/or the ski runner of the skis.

Therefore, there is a desire for a ski assembly for a snowmobile that can be adjusted for operation of the snowmobile in different riding conditions while not causing premature wear when riding on surfaces that are not covered with snow or ice.

SUMMARY

One object of the present technology is to ameliorate at least some of the inconveniences of the prior art.

According to one aspect of the present technology, there is provided a snowmobile ski assembly including a ski having a bottom, at least one wheel rotatably connected to the ski and the at least one wheel having a lower portion extending below the bottom of the ski. The snowmobile ski assembly has a ski runner being operatively connected to the ski, the ski runner being movable relative to the ski between a first position and a second position, a bottom of the ski runner being above the lower portion of the at least one wheel when the ski runner is in the first position, and the bottom of the ski runner being below the lower portion of the at least one wheel when the ski runner is in the second position.

In some implementations, the snowmobile ski assembly also has a ski runner adjustment assembly connected to the ski runner, the ski runner adjustment assembly selectively moving the ski runner between the first and second positions.

In some implementations, the bottom of the ski runner is closer to the bottom of the ski in the first position than in the second position.

In some implementations, the ski defines a slot, and the ski runner is disposed in the slot.

In some implementations, the at least one wheel is laterally aligned with a longitudinal centerline of the ski.

In some implementations, the ski has a central keel, and the lower portion of the at least one wheel extends below the central keel of the ski.

In some implementations, the ski has an external keel. The external keel is laterally offset from a longitudinal centerline of the ski, and the lower portion of the at least one wheel extends below the external keel of the ski.

In some implementations, the ski pivots about a laterally extending ski pivot axis. The ski runner adjustment assembly is connected about the ski pivot axis, and the ski pivots about the ski pivot axis relative to the ski runner adjustment assembly.

In some implementations, the ski pivots about a laterally extending ski pivot axis. The at least one wheel includes a front wheel rotatably connected to the ski forward of the ski pivot axis, and a rear wheel rotatably connected to the ski rearward of the ski pivot axis.

In some implementations, the rear wheel is rotatably connected to the ski rearward of the ski runner.

In some implementations, the lower portions of the front and rear wheels extend below a central keel of the ski.

In some implementations, the ski has an external keel. The external keel is laterally offset from a longitudinal centerline of the ski, and lower portions of the front and rear wheels extend below the external keel of the ski.

In some implementations, the front wheel is rotatably connected to the ski via a front wheel frame, and the rear wheel is rotatably connected to the ski via a rear wheel frame.

In some implementations, the front wheel frame and the rear wheel frame define a portion of a central keel of the ski.

In some implementations, the front wheel frame is received in the ski in a front slot, and the rear wheel frame is received in the ski in a rear slot.

In some implementations, the front wheel frame has a front ski adapter and a front wheel adapter. The front ski adapter connects the front wheel adapter to the ski. The front wheel is rotatably connected to the front wheel adapter. The rear wheel frame has a rear ski adapter and a rear wheel adapter. The rear ski adapter connects the rear wheel adapter to the ski. The rear wheel is rotatably connected to the rear wheel adapter.

In some implementations, the front wheel adapter is received inside the front ski adapter, and the rear wheel adapter is received inside the rear ski adapter.

In some implementations, the ski has a handle connected to an upturned front portion of the ski.

In some implementations, the at least one wheel includes a front wheel rotatably connected to the ski forward of the slot and a rear wheel rotatably connected to the ski rearward of the slot. The front wheel is rotatably connected to the ski via a front wheel frame. The front wheel frame has a front slot adapted for receiving a front portion of the ski runner. The rear wheel is rotatably connected to the ski via a rear wheel frame. The rear wheel frame has a rear slot adapted for receiving a rear portion of the ski runner.

For the purposes of the present application, terms related to spatial orientation such as forward, rearward, front, rear, upper, lower, left, and right, are as they would normally be understood by a rider of the snowmobile sitting thereon in a normal driving position with the snowmobile being upright and steered in a straight ahead direction.

Should there be any difference in the definitions of term in this application and the definition of these terms in any document included herein by reference, the terms as defined in the present application take precedence.

DETAILED DESCRIPTION

With reference toFIG. 1, a snowmobile20will be described. Although a snowmobile20is presented herein, it is contemplated that aspects of the present technology could be applied to other types of vehicles having skis for operation on snow.

The snowmobile20has a front end22and a rear end24, which are defined consistently with the forward travel direction of the snowmobile20. The snowmobile20includes a frame26. The frame26includes a tunnel28, a motor cradle portion30and a front suspension assembly portion32. A motor34, which is schematically illustrated inFIG. 1, is supported by the motor cradle portion30. In the present implementation, the motor34is a two-stroke, two-cylinder, internal combustion engine. However, it is contemplated that other types of motors could be used such as, but not limited to, an electric motor or a four-stroke internal combustion engine. The engine34powers an electrical system36of the snowmobile20, the electrical system36being also schematically illustrated inFIG. 1.

An endless drive track38is disposed under the tunnel28. The endless drive track38is operatively connected to the engine34through a continuously variable transmission (CVT, not shown). The endless drive track38is suspended for movement relative to the frame26, by a rear suspension assembly40. The rear suspension assembly40includes a pair of spaced apart slide rails42, rear suspension arms44,46and shock absorbers48,50. The slide rails42engage the inner side of the endless drive track38. The rear suspension arms44,46and the shock absorbers48,50pivotally connect the tunnel28to the slide rails42. The endless drive track38is driven to run about the rear suspension assembly40for propulsion of the snowmobile20. A plurality of rollers52define the path over which the endless drive track38travels.

A fuel tank54is supported on top of the tunnel28. A seat56is disposed on the fuel tank54and is adapted to support a rider. Two footrests58(only one of which is shown) are positioned on opposite sides of the tunnel28below the seat56to support the rider's feet. The footrests58are integrally formed with the tunnel28.

Left and right ski assemblies100are positioned at a front of the snowmobile20(only the left one being shown inFIG. 1). Each ski assembly100includes a ski102, a corresponding ski leg104and other components that will be described in greater detail below. Each ski assembly100is attached to the front suspension assembly portion32of the frame26via a front suspension assembly60. Each front suspension assembly60includes an upper A-arm62, a lower A-arm64and a shock absorber66. Each ski leg104is pivotally connected to its corresponding upper and lower A-arms62,64and the corresponding shock absorber66is connected between the lower A-arm64and the front suspension assembly portion32of the frame26. It is contemplated that other types of front suspension assemblies could be used. It is contemplated that the snowmobile20could have only one ski assembly100.

Referring toFIGS. 1 and 13, a steering assembly including a steering column68and a handlebar70is supported by the frame26. The steering column68is attached at its upper end to the handlebar70, which is positioned forward of the seat56. The steering column68is operatively connected to the ski legs104by steering rods72in order to steer the skis102, and thereby the snowmobile20, when the handlebar70is turned.

A display cluster80(a portion of which is shown inFIG. 28) is provided in front of the seat56to display information, such as the vehicle speed, engine speed, vehicle mode, temperature and the like, to the driver of the snowmobile20. The display cluster80includes one or more gauges, display screens, indicator lights and sound output devices such as speakers, alarms and the like.

Referring toFIG. 1, fairings74enclose the engine34, the electrical system36and the CVT, thereby providing an external shell that protects the engine34, the electrical system36and the CVT. The fairings74include a hood and one or more side panels that can be opened to allow access to the engine34, the electrical system36and the CVT when this is required, for inspection or maintenance of the engine34, the electrical system36and/or the CVT for example. A windshield76is connected to the fairings74forward of the handlebar70. It is contemplated that the windshield76could be attached directly to the handlebar70.

Turning now toFIGS. 2 to 15, the left and right ski assembly100of the snowmobile20will be described in more detail. Alternative implementations of the ski assembly will be described with reference toFIGS. 16 to 20. The left ski assembly100includes the left ski102, the left ski leg104, a left ski runner106and a left ski runner adjustment assembly108. In the right ski assembly100, the right ski102, the right ski runner106and the right ski runner adjustment assembly108are identical to those of the left ski assembly100, and the right ski100and the right ski leg104are a mirror image of the left ski leg104. Accordingly, for simplicity, the components of the left and right ski assembly100will be described at once for both ski assemblies100, unless mentioned otherwise. The ski runner adjustment assembly108that is shown inFIGS. 1 to 15is in accordance with an implementation of a ski runner adjustment assembly described in US 2015/0314799 A1 published Nov. 5, 2015, which is incorporated herein by reference in its entirety. It is contemplated that other implementations of a ski runner adjustment assembly could be used, such as the alternative implementations described in US 2015/0314799 A1. It is contemplated that the left and right ski legs104could be identical, or that the left and right ski legs104could have features that differ from each other. It is contemplated that one or more of the right ski102, the right ski runner106and the right ski runner adjustment assembly108could be a mirror image of those of the left ski assembly100or could have one or more features that differ from those of the left ski assembly100. It is contemplated that in some implementations of the ski assembly100, such as in a replacement ski assembly for replacing an existing ski of a snowmobile20, the ski leg104could be omitted as a suitable ski leg104may already be provided on the snowmobile20.

Referring toFIGS. 1 to 15, the ski assembly100includes a front wheel110and a rear wheel112. The front wheel110has a lower portion116and the rear wheel has a lower portion118. Both lower portions116,118extend below a bottom120of the ski102. In the ski assembly100, the ski runner106is operatively connected to the ski102via the ski runner adjustment assembly108. The ski runner adjustment assembly108is used to move the ski runner106inside a slot122(FIG. 12) defined in the ski102to change an amount by which the ski runner106extends below the ski102. By changing the amount by which the ski runner106extends below the ski102, the ski assembly100can be adjusted for different riding conditions. When the ski runner106is moved to a raised position, as shown inFIGS. 2 to 6, a bottom124of the ski runner106extends above the lower portions116,118of the front and rear wheels110,112respectively. When the ski runner106is moved to a lowered position as shown inFIGS. 9 to 11, the bottom124of the ski runner106extends below the lower portions116,118of the front and rear wheels110,112respectively.

Referring toFIGS. 2, 6, 9 and 11, the ski102is pivotally connected to a bottom of the ski leg104by a bolt126, or another fastener such as a rivet for example. The bolt126defines a laterally extending ski pivot axis128about which the ski102pivots relative to the ski leg104. The ski runner adjustment assembly108is connected to the bolt126at the ski pivot axis128and to the ski leg104. As such, the ski102pivots about the ski pivot axis128relative to the ski runner adjustment assembly108. The slot122defined in the ski102, in which the ski runner106is disposed, stabilizes the ski runner106laterally and prevents rotation of the ski runner106relative to the ski102while allowing the ski runner106to move therein.

The only vertical load-bearing connection between the ski runner106and the ski leg104is provided via the ski runner adjustment assembly108as the ski runner106is not connected directly to the ski102. As such, the ski102only bears a vertical load when at least one of the bottom120of the ski, the front wheel110and the rear wheel112is in contact with the surface on which the snowmobile20rides. As can be seen inFIG. 2where the ski runner106is in the raised position, when the snowmobile20is disposed on flat, level ground G, such as when riding on asphalt, concrete or wood, the ski assembly100is supported on the ground G by the front wheel110and the rear wheel112. Under these conditions, a portion of the weight of the snowmobile20results in a force passing through the ski leg104, the ski102, the front wheel110, and the rear wheel112to the ground G without passing through the ski runner adjustment assembly108and the ski runner106. As can be seen inFIG. 9where the ski runner106is in the lowered position, when the snowmobile20is disposed on flat, level ground G, such as when riding on an icy level surface, the ski assembly100is supported on the ground G by the ski runner106as the bottom120of the ski102, the front wheel110and the rear wheel112are spaced from the ground G. Under these conditions, a portion of the weight of the snowmobile20results in a force passing through the ski leg104, the ski runner adjustment assembly108and the ski runner106to the ground G without passing through the ski102.

With reference toFIGS. 6 and 11, the ski leg104has an upper front tab130, a lower front tab132, and a rear tab134. A ball joint138(shown in dotted lines) is connected to the upper front tab130by a nut136(shown in dotted lines) to connect the ski leg104to the end of the upper A-arm62. A ball joint142(shown in dotted lines) is connected to the lower front tab132by a nut140(shown in dotted lines) to connect the ski leg104to the end of the lower A-arm64. A ball joint146(shown in dotted lines) is connected to the rear tab134by a nut144(shown in dotted lines) to connect the ski leg104to the end of the steering rod72. When the rider of the snowmobile20turns the handlebar70, the steering rod72pushes or pulls, as the case may be, on the rear tab134. As a result, the ski leg104pivots about a ski leg pivot axis148passing through the centers of the ball joints138,142.

With reference toFIGS. 2, 3, 9, 10 and 12, the ski102has a ski body150. The ski body150includes a central keel152provided on the bottom120of the ski body150and a handle154connected to the upturned front portion of the ski body150. The central keel152is positioned inline with a longitudinal centerline156of the ski body150. A portion of the central keel152is formed by a front wheel frame158and a rear wheel frame160, as shown inFIG. 12. The front wheel110is rotatably connected to the ski body150through the front wheel frame158and the rear wheel112is rotatably connected to the ski body150through the rear wheel frame160. As shown inFIG. 5, the front wheel frame158is received in a front slot162and the rear wheel frame160is received in a rear slot164; both being defined in the ski body150. Referring toFIGS. 5 and 12, the front wheel frame158can only be inserted in the front slot162in a unique fashion and the rear wheel frame160can only be inserted in rear slot164in another unique fashion as the front and rear slots162,164differ in shape and the front wheel frame158and the rear wheel frame160respectively have a corresponding shape. This feature prevents the front wheel frame158from being inserted in the front slot162in a wrong way, and prevents the front wheel frame158from being inserted in the rear slot164, and vice-versa.

Referring toFIGS. 5, 7 and 8, the front wheel frame158will be described in more detail. The front wheel frame158includes a front ski adapter166and a front wheel adapter168.

The front ski adapter166has front and rear flanges169,171respectively. The front and rear flanges169,171are configured to sit on top of the ski body150. The front ski adapter166connects to the ski body150through six fasteners170extending through the bottom120of the ski102and into the front ski adapter166. The rear face of the front ski adapter166has a slot210which will be described below. The front ski adapter166has front and rear bottom protrusions172,173respectively. The front and rear bottom protrusions172,173match the width of the rear wheel frame160. The front and rear bottom protrusions172,173of the front ski adapter166and the rear wheel frame160form part of the central keel152of the ski body150.

The front wheel adapter168is shaped to be received inside the front ski adapter166. The front wheel adapter168connects to the front ski adapter166via fasteners (not shown) passing through holes174defined in both the front ski adapter166and the front wheel adapter168. The front wheel adapter168has a tongue177(FIG. 5) protruding in the front face of the front wheel adapter168. The tongue177is shaped to fit within a corresponding slot179defined on the bottom of the front ski adapter166by the front protrusion172. Spaced apart shoulders181protrude on the rear face of the front wheel adapter168. The shoulders181of the front wheel adapter168are configured to abut on corresponding shoulders (not shown) defined in the front ski adapter166. The front ski adapter166has a protrusion183(FIG. 5) extending on the front face of the protrusion173. The protrusion183is shaped to fit within a corresponding slot185(FIG. 8) defined between the shoulders181on the rear face of the front wheel adapter168.

The front wheel110is inserted in the front wheel adapter168and is connected thereto using a male bolt176and a female bolt178. The shank of the female bolt178forms the axle about which the front wheel110rotates. The front wheel adapter168has a bottom aperture180configured so that only the lower portion116of the front wheel110extends therethrough. As can be seen inFIG. 6, the length of the bottom aperture180is smaller than the diameter of the front wheel110. Thus, when the front wheel110is connected to the front wheel adapter168, infiltration and accumulation of snow, ice and/or water is reduced in the front wheel adapter168. The front wheel110is inserted in the front wheel adapter168through the top of the front wheel adapter168before being connected thereto using the male and female bolts176,178respectively, and before the front wheel adapter168is connected to the front ski adapter166.

Referring toFIGS. 5 and 6, the rear wheel frame160is understood to have a configuration similar to the front wheel frame158, i.e. the rear wheel frame160includes a rear ski adapter182and a rear wheel adapter184. In addition, it can be seen inFIGS. 5 and 12that the rear wheel frame160is connected to the ski body150using four fasteners170instead of six. It is contemplated that the front wheel frame158and the rear wheel frame160could be configured otherwise.

Referring toFIGS. 3, 5, 10 and 12, the ski body150further includes an external keel186. The external keel186is disposed on the left side of the bottom120of the left ski102. On the right ski102, the external keel186is disposed on the right side of the bottom120of the ski102. The ski body150, the central keel152, the front wheel frame158, the rear wheel frame160and the external keel186are made of ultra-high molecular weight (UHMW) polyethylene. The front and rear wheels110,112are made of rubber that is connected to a rim113(FIG. 8) made of ultra-high molecular weight (UHMW) polyethylene. It is contemplated that the ski body150, the central keel152, the front wheel frame158, the rear wheel frame160, the front wheel110, the rear wheel112and the external keel186could be made of other suitable materials. It is also contemplated that the ski body could differ from the one shown in the present implementation. For instance, the ski body could be free of an external keel186and/or the central keel152could be laterally offset from the longitudinal centerline of the ski body. As mentioned above, the front portion of the ski body150curves upwards. The middle and rear portions of the ski body150, as seen inFIGS. 2 and 9, are generally flat except for a portion adjacent to the rear end that is angled upwards.

Referring toFIGS. 4, 5, 11 and 12, the front and rear of the ski body150are tapered and the sides of the middle portion are parallel. It is contemplated that the ski body150could have a general shape other than as shown in the illustrated implementation. For example, the ski body150could have a sidecut or a flat rear end. The ski body150has left and right longitudinally extending walls188extending upwards from an upper surface of the ski body150. The walls188are disposed laterally inwards of the lateral sides of the ski body150. It is contemplated that the walls188could be disposed along the lateral sides of the ski body150, and that they could extend more or less in the longitudinal direction of the ski body150than as shown in the illustrated implementation. The handle154is connected to the ski body150between the walls188. Apertures190are defined in the walls188to receive the bolt126used to fasten the ski102to the ski leg104. The portions of the walls188surrounding the apertures190are thicker than other portions of the walls188in order to reinforce these portions of the walls188. Ribs192, extending laterally outwards from the walls188, provide structural reinforcement to the walls188. It is contemplated that ribs extending laterally inwards from the walls188could be provided. It is also contemplated that the ribs192could be omitted.

Referring toFIGS. 5 and 12, the slot122is defined by and extends through the ski body150and the central keel152. The slot122extends longitudinally between the walls188and is disposed along the longitudinal centerline156of the ski102. It is contemplated that the slot122could be laterally offset from the longitudinal centerline156of the ski102. It is also contemplated that the slot122could be defined in the central keel152and the ski body150but only open at a bottom of the central keel152and not extend through the central keel152and the ski body150. The longitudinal central portion194of the slot122is wider than the portions of the slot122adjacent to it in order to accommodate a connection between the ski runner106and the ski runner adjustment assembly108.

Referring toFIG. 12, a rear end196of the slot122is defined by the walls198of the rear ski adapter182. The rear ski adapter182includes a slot200. The slot200defines a rear wall202of the slot122. The slot200of the rear ski adapter182is adapted for receiving a rear portion204(FIG. 6) of the ski runner106. A front end206of the slot122is defined by the walls208of the front ski adapter166. The front ski adapter166has the slot210(FIG. 8). The slot210defines a front wall212of the slot122. The slot210is adapted for receiving a front portion214(FIG. 6) of the ski runner106.

In addition, the slots200,210include widened portions216,218respectively. The widened portions216,218may improve the liberty of movement of the ski runner106in the slots200,210. As can be seen inFIGS. 6, 11 and 12, the rear and front walls202,212of the slot122are parallel to each other. In the present implementation, the walls202,212are flat. It is contemplated that the walls202,212could not be flat, but still could provide parallel surfaces along which the ski runner106can move.

Referring toFIGS. 6 and 11, the ski runner106has a ski runner body220. The ski runner body220has a rear flat wall222and a front flat wall224. The walls222,224are parallel to each other. When the ski runner106is inserted in the slot122, the walls220,224are parallel to the walls198,208of the rear and front ski adapters182,164respectively. When the ski runner106is moved in the slot122, the wall222of the ski runner body220translates along the walls198and the wall224of the ski runner body220translates along the walls208. The ski runner body220has a lower edge referred to herein as the ground engaging edge226. The ground engaging edge226is straight and perpendicular to the walls222,224. It is contemplated that the ground engaging edge could not be straight. For example, the ground engaging edge226could be convex. It is also contemplated that the ground engaging edge226could not be perpendicular to the walls222,224. The ground engaging edge226forms a channel inside which are received wearbars228. The wearbars228are brazed to the ski runner body220. The wearbars228, as their name suggest, are intended to make contact with the ground G and wear instead of the ski runner body220. The wearbars228are sometimes referred to as carbides in reference to the material from which they are usually made. It is contemplated that the wearbars228could be connected to the ski runner body220by other means. It is also contemplated that the wearbars228could be omitted. In addition, the ski runner body220defines an arcuate slot230in a central portion thereof. The arcuate slot230is closer to the rear wall222than to the front wall224.

Turning now toFIGS. 2, 6, 9, 11, 14 and 15, the ski runner adjustment assembly108will be described in more detail. The ski runner adjustment assembly108includes a housing300inside which an adjustment mechanism302is housed in part. As will be explained in greater detail below, actuation of the adjustment mechanism302causes the ski runner106to be moved up or down inside the slot122.

The housing300has a pair of spaced apart tabs304. The tabs304define apertures306inside which bushings308are inserted. It is contemplated that the bushings308could be omitted. The bolt126defines an axle about which the ski102can pivot, i.e. the ski102can pivot relative to the ski pivot axis128. The bolt126is received in the bushings308to connect the housing300to the ski leg104. The ski leg104is received between the tabs304. The housing300also has a tab310defining a frustoconical aperture312. As can be seen inFIGS. 6 and 11, a rubber grommet314is disposed in the aperture312of the tab310. The nut140used to connect the ski leg104to the ball joint142connected to the end of the lower A-arm64is received in the grommet314. As a result, the ski runner adjustment assembly108is prevented from pivoting about the pivot axis148relative to the ski leg104. The housing300also defines a slot316(FIG. 15) in a front thereof, the function of which will be described below.

The adjustment mechanism302has two main parts: a shaft318having external threads and a shaft320having internal threads. The threaded portion of the shaft318is received in the threaded portion of the shaft320. As the shaft318rotates, the shaft320slides in and out of the housing300. It is contemplated that the shaft318could have the internal thread and that the shaft320could have the external thread. Other types of adjustment mechanisms are contemplated. For example, the shafts318,320could be replaced by a rack and pinion assembly.

The lower portion of the shaft318is received in the housing300and the top portion of the shaft318protrudes from the top of the housing300. The shaft318is received in a ball bearing322that is press-fit in a top of the housing300. As such, the shaft318can rotate about a rotation axis324. However, the shaft318does not slide along the rotation axis324. The top of the ball bearing322abuts an inner flange326defined by the housing300. The bottom of the ball bearing322abuts the top of a sleeve328inserted in the housing300. The bottom of the sleeve328abuts a C-clip330clipped in the housing300. As such, the C-clip330and the flange326prevent the ball bearing322and the sleeve328from sliding along the rotation axis324. The sleeve328also defines a slot332in alignment with the slot316of the housing300. The shaft318has a shoulder334that abuts the bottom of the ball bearing322. The portion of the shaft318below the shoulder334has an external thread thereon.

The shaft320is received in the sleeve328inside the housing300and protrudes from a bottom of the housing300. The shaft320has a bore336defined in a top thereof. The bore336has an internal thread. The lower threaded portion of the shaft318is received in and engages the thread in the bore336. Grease could be provided in the interface338between the shafts318,320. An aperture340extends from an outer surface of the shaft320in order to permit water entering the bore336to be drained therefrom. The aperture340opens in a front of the shaft320such that water draining from the bore336then drains out of the sleeve328and the housing300via the slot332.

A screw342is inserted through the slots316,332and into a counterbored aperture344in the shaft320. As can be seen inFIG. 15, the aperture344is perpendicular to the rotation axis324and is disposed below the aperture336. As explained above, turning the shaft318causes the shaft320to move along the rotation axis324. The screw342abuts the sides of the slots316,332thereby preventing the shaft320to rotate about the axis rotation with the shaft318. The screw342also prevents the shaft320from moving too far down along the rotation axis324by coming into contact with the bottom portion of the slots316,332, thereby stopping the shaft320before the threads of the shafts318,320disengage from each other. The upward movement of the shaft320is stopped when the top end of the shaft320comes into contact with the shoulder334of the shaft318as shown inFIG. 15.

The screw342is also inserted through a cover346disposed outside the housing300so as to cover the slot316in the housing to reduce the entry of snow and water into the housing300via the slot316. A clearance348(FIG. 14) is provided in the bottom center of the cover346to permit water drainage from the interior of the housing300through the slots316,332. An O-ring350is disposed between the head of the screw342and the cover346to prevent the entry of snow and water. The cover346moves along the outer surface of the housing300with the shaft320as the shaft320is moved along the rotation axis324. For this reason, the cover346is also used as a position indicator. The cover346is provided with triangular projections352that provide an indication of the position of the shaft320, and therefore of the ski runner106, along markings354formed on the outer front surface of the housing300. To ensure that the screw342is not screwed too far into the aperture344of the shaft320, which would squeeze the cover346between the screw head of the screw342and the outer surface of the housing300, thereby hindering movement of the shaft320, the screw320has a shoulder that abuts the bottom of the counterbore of the aperture344once it has been sufficiently screwed in the aperture344.

In order to turn the shaft318, a knob356is mounted over the portion of the shaft318protruding from the top of the housing300. The knob356is fixed to the shaft318by a screw358. To prevent the knob356from turning relative to the shaft318, the central portion of the knob356disposed over the shaft318has a polygonal shape and the top portion of the shaft318has a corresponding polygonal shape. Alternatively, the central portion of the knob356and the top portion of the shaft318could be splined, keyed, or circular but for corresponding flat surface for example. The knob356has a generally oval cross-section (as viewed from above inFIG. 4), with a number of teeth360protruding from its sides to facilitate gripping of the knob356by the user.

Although the shaft320can have an infinite number of positions within its range of positions, in order to make it easier for the user to set the same position on both the left and right ski assemblies100, the ski runner adjustment assembly108provides auditory and haptic feedbacks to the user at a number of pre-set positions. To provide the auditory and haptic feedbacks, the housing300has a pair of notches362along the top edge thereof which are selectively engaged by a clicker364. The clicker364is an annulus disposed in the knob356that is biased against the top edge of the housing300by a spring366. The clicker364has a pair of protrusions on the bottom thereof. When the knob356is turned, the protrusions on the bottom of the clicker364eventually fall into the notches362thereby producing a clicking sound. The spring366provides some resistance to turning the knob356to make the protrusions on the bottom of the clicker364come out of the notches362thereby provide a haptic feedback that a pre-set position has been reached. As the notches362are provided on opposite sides of the housing300, the pre-set positions correspond to every half turn of the knob356. It is contemplated that only one or more than two notches362could be provided. It is also contemplated that only one or more than two protrusions could be provided on the bottom of the clicker364. It is also contemplated that the number of notches362and the number of protrusions provided on the bottom of the clicker364could differ. It is contemplated that the clicker364and its associated component could be omitted and that the user could rely only on the position indicator (i.e. cover346) and markings354to determine the position of the shaft320, and therefor the ski runner106. It is contemplated that the position indicator (i.e. cover346) and markings354could also be omitted. It is contemplated that other means could be provided to determine the position of the ski runner106relative to the ski102, such as, for example, level markings on the side of the ski runner106.

To connect the shaft320to the ski runner106, a pair of bent arms368is connected to lower portion of the shaft320. It is contemplated that the arms368and the shaft320could be integrally formed. Each arm has an aperture370. The ski runner106is inserted between the arms368with the arcuate slot230(FIGS. 6 and 11) aligned with the apertures370. A connector in the form of a pin372(FIGS. 6 and 11) is inserted into the apertures370of the arms370and the arcuate slot230, thereby connecting the ski runner106to the ski runner adjustment assembly108.

The pin372is the only connection between the ski runner106and any other part of the ski assembly100such that the ski runner106is held in place with respect to ski102by the adjustment mechanism302and ski leg104. As such, forces applied to the ski runner106are transferred to the adjustment mechanism302by the connection provided therebetween by the pin372, then from the adjustment mechanism302to the housing300by the connection provided therebetween by the bearing322, and the from the housing300to the ski leg104by the connection provided therebetween by the bolt126.

To adjust the position of the ski runner106relative to the ski102to change the amount by which the ski runner106protrudes from the central keel152, a user only needs to turn the knob356. When the knob356is turned, the shaft320moves along the rotation axis324, which in turn causes the pin372to move in the same direction along an adjustment axis (not shown) parallel to the rotation axis324.

Starting from the position of the ski runner106shown inFIGS. 2 to 6, by turning the knob356in one direction (i.e. clockwise), the ski runner adjustment assembly108moves the pin372down along the adjustment axis (not shown) which causes the ski runner106to move down along a translation axis (not shown) to a lowered position, such as the one shown inFIGS. 9 to 11, where the distance between the bottom124of the ski runner106and the bottom120of the ski102is greater than in the raised position shown inFIGS. 2 to 6. Moreover, it can be seen inFIGS. 2 to 6that the bottom124of the ski runner106extends above the lower portions116,118of the front and rear wheels110,112respectively. InFIGS. 9 to 11, the bottom124of the ski runner106extends below the lower portions116,118of the front and rear wheels110,112respectively. It should also be understood that the ski runner106could be positioned at positions intermediate the raised position and the lowered position shown respectively inFIGS. 2 to 6andFIGS. 9 to 11.

Turning now toFIG. 16, an alternative implementation of the ski runner adjustment assembly108will be described.FIG. 16illustrates a portion of a steering assembly and a ski assembly100as described above, but having a ski runner adjustment assembly400. For simplicity, elements of the ski runner adjustment assembly400that are similar to those of the ski runner adjustment assembly108described above have been numbered with the same reference numerals and will not be described again. In this implementation, the knob356of the ski runner adjustment assembly108and its related components, such as the clicker364and the spring366, are omitted.

An electric motor402is received in a housing404. The housing404is connected to the ski leg104and to a top portion of the ski runner adjustment assembly400. The electric motor402has an output shaft (not shown) and the output shaft includes a socket (not shown). The socket has a polygonal shape and the top portion of the shaft318has a corresponding polygonal shape. Alternatively, the socket and the top portion of the shaft318could be splined, keyed, or circular but for corresponding flat surface for example. When the top portion of the shaft318is connected to the socket of the output shaft of the electric motor402, the electric motor402is operatively connected to the shaft318. The electric motor402can be activated so that the output shaft is rotated clockwise or counter clockwise. A wire406is connected to the electric motor402. The wire406extends along the steering column68and connects to a switch408that is connected to the handlebar70or elsewhere on the snowmobile20such that the rider may operate the switch408while riding. The switch408is understood to be connected to the electrical system36of the snowmobile20. The switch408is a three-position switch having the following positions: an “off” position, turning off the electric motor402; a “ski runner up” position activating the electric motor402such that the ski runner106moves upwardly in the slot122; and a “ski runner down” position activating the electric motor402such that the ski runner106moves downwardly in the slot122. When released from the “ski runner up” position, the switch408returns to the “off” position. When released from the “ski runner down” position, the switch408also returns to the “off” position. It is contemplated that the switch408could differ from the one described herein. It is to be understood that, in one implementation, the position of the ski runners106can be fully controlled by the rider. In some implementations, it is contemplated that each discrete actuation (i.e. click) of the switch408could move the ski runners106up or down from a predetermined amount.

It is also to be understood that both left and right ski runner adjustment assemblies400include an electric motor402, a housing404and a wire406. Both left and right electric motors402are activated using a single switch408so that both ski runners106are simultaneously moved up or down by the same amount. The snowmobile20includes an electronic control module connected to the switch408and connected to the electric motor402for each of the left and right ski runner adjustment assemblies400for controlling the ski runners106of both ski assemblies100.

An illustrative scenario of the operation of the ski runner adjustment assembly400will now be described. The illustrative scenario is based on the hypothesis that both the left and right ski runners106extend initially below the lower portions116,118of the front and rear wheels110,112respectively (i.e. the ski runners106are in the lowered position shown inFIGS. 9 to 11) and that the snowmobile20is ridden on a trail covered with soft snow. As the snowmobile20arrives at a paved road that the trail crosses, the rider stops the snowmobile20and the switch408is moved by the rider from the “off” position to the “ski runner up” position. The electric motors402of the left and right ski runner adjustment assemblies400are activated and rotate the respective shaft318so that the left and right ski runners106are moved upwardly simultaneously. When the front and rear wheels110,112make contact with the ground surface G and when the ski runners106have been moved upwardly such that the bottom124of the ski runners106are above the lower portions116,118of the wheels110,112respectively, the rider releases the switch408which returns to the “off” position. The rider then drives the snowmobile20across the paved road. When the snowmobile20is ridden on the paved road, the front and rear wheels110,112provided on the left and right skis102reduce wear of at least one of the central keel152, the external keel186and the wearbars228of each ski assembly100. Once the paved road is crossed, the rider stops the snowmobile20where the trail covered with soft snow continues. The switch408is moved by the rider from the “off” position to the “ski runner down” position. The electric motors402of the left and right ski runner adjustment assemblies400are activated and rotate the respective shaft318such that the left and right ski runners106are moved downwardly simultaneously. When the bottom124of the ski runners106extend below the lower portions116,118of the front and rear wheels110,112respectively and when the ski runners106have been moved downwardly by a sufficient amount, the rider releases the switch408which returns to the “off” position. The rider then drives the snowmobile20on the trail.

It is contemplated that the ski runner adjustment assembly400could further include some kind of auditory and/or visual feedback apparatus for indicating to the rider the position of the ski runners106with respect to the front and rear wheels110,112of each ski assembly100. For instance, a visual indication could appear on a display cluster of the snowmobile20indicating the position of the ski runners106, and/or a sound could be emitted when the ski runners106are moved such that the bottom124of the ski runners106extend below the lower portions116,118of the front and rear wheels110,112respectively. It is contemplated that the indicator could be provided in the display cluster80(FIG. 28) or a separate indicator located on the handlebar70.

Turning now toFIGS. 17 and 18, an alternative implementation of the ski assembly100will be described.FIGS. 17 and 18illustrate a ski assembly500. For simplicity, elements of the ski assembly500that are similar to those of the ski assembly100described above have been numbered with the same reference numerals and will not be described again.

The ski assembly500shown inFIGS. 17 and 18is a left ski assembly500. The ski assembly500has a single wheel502positioned in a middle portion of the ski504. The wheel502is rotatably connected to the ski504through an axle506. The ends of the axle506are connected to the longitudinally extending walls188of the ski504. The axle506is positioned below the ski pivot axis128(shown inFIGS. 2, 4 and 6). The ski assembly500further includes a ski runner508. The ski runner508has a slot510. The slot510is shaped so as to provide clearance to the wheel502while allowing for vertical movement of the ski runner508. The ski runner508is movable upwardly and downwardly using the ski runner adjustment assembly108, as described above. It is contemplated that the lowest position into which the ski runner508can be configured corresponds to the wheel502contacting the upper portion512of the slot510of the ski runner508. The ski504has a central keel514provided on a bottom516of the ski504. As can be seen onFIG. 17, a lower portion518of the wheel502extends below the central keel514, the bottom516of the ski504and a bottom520of the ski runner508. Still referring toFIG. 17where the ski runner508is in the raised position, when the snowmobile20is disposed on flat, level ground G, such as when riding on asphalt, concrete or wood, the ski assembly500is supported on the ground G by the wheel502. As can be seen inFIG. 18where the ski runner508is in the lowered position, when the snowmobile20is disposed on flat, level ground G, such as when riding on an icy level surface, the ski assembly500is supported on the ground G by the ski runner508as the central keel514, the bottom516of the ski504and the wheel502are spaced from the ground G.

Turning now toFIGS. 19 and 20, an alternative implementation of the ski assembly100will be described.FIGS. 19 and 20illustrate a ski assembly600. For simplicity, elements of the ski assembly600that are similar to those of the ski assembly100described above have been numbered with the same reference numerals and will not be described again.

The ski assembly600shown inFIGS. 19 and 20is a left ski assembly600. The ski assembly600includes a ski604having a ski body606. The ski body606has a bottom608and a central keel152. The ski assembly600includes the ski leg104and the ski runner106is connected to the ski runner adjustment assembly108, as described above. The ski assembly600has four wheels: a front right wheel610, a rear right wheel614, a front left wheel618and a rear left wheel620. Each one of the wheels610,614,618,620extends through a corresponding aperture defined in the ski body604: a front right aperture622, a rear right aperture624, a front left aperture628and a rear left aperture626. The left and right front wheels618,610are rotatably connected to the ski body604via a front axle636extending through the ski body606forward of the ski runner106. The left and right rear wheels618,614are rotatably connected to the ski body606via a rear axle634extending through the ski body606rearward of the ski runner106. Each one of the wheels610,614,618,620has a bottom portion. InFIG. 19, only bottom portions612,616of the right front wheel610and the right rear wheel614, respectively, are shown. The wheels610,614,618,620are disposed on the outer sides of the longitudinally extending walls188of the ski body604. The wheels610,614,618,620are laterally offset from the ski runner106. As can be seen inFIG. 19where the ski runner106is in the lowered position, when the snowmobile20is disposed on flat, level ground G, such as when riding on an icy level surface, the ski assembly600is supported on the ground G by the ski runner106and the bottom608of the ski604and the wheels610,614,618,620are spaced from the ground G. In the case where the ski runner106is in the raised position when the snowmobile20is disposed on flat, level ground G, such as when riding on asphalt, concrete or wood, the ski assembly600is supported on the ground G by the wheels610,614,618,620. In an alternative implementation, the ski assembly600only has one of the front wheels610,618and only one of the rear wheels614,620. For example, the ski assembly600could only have the front right wheel610and the rear left wheel620. In such an implementation, the ski body606would only be provided with the apertures622,626corresponding to the wheels610,620respectively.

Turning now toFIGS. 21 to 28, an alternative implementation of the ski assembly100and ski runner adjustment assembly108will now be described.FIGS. 21 to 26illustrate a ski assembly700having a ski runner adjustment assembly800. The ski assembly700has some elements that are similar to the ski assembly100described above and the ski runner adjustment assembly800has some elements that are similar to the ski runner adjustment assembly108described above. For simplicity, elements of the ski assembly700that are similar to those of the ski assembly100described above have been numbered with the same reference numerals and will not be described again in detail. Also for simplicity, elements of the ski runner adjustment assembly800that are similar to those of the ski runner adjustment assembly108described above have been numbered with the same reference numerals and will not be described again in detail.

The ski assembly700and ski runner adjustment assembly800shown inFIGS. 21 to 26is a left ski assembly700and left ski runner adjustment assembly800. The snowmobile20also includes a right ski assembly700and corresponding right ski runner adjustment assembly800. As the right ski assembly700and ski runner adjustment assembly800are respectively similar to the left ski assembly700and ski runner adjustment assembly800, only the left one will be described herein.

With reference toFIGS. 21 to 26, the ski assembly700includes a ski102, a ski leg104and a ski runner106. The ski102has a ski body150having a bottom120, a central keel152and a handle154. The central keel152is positioned inline with a longitudinal centerline156of the ski body150and entirely formed by the ski body150. A slot702(FIG. 24) is defined by and extends through the central keel152. The ski runner106is disposed in the slot702(FIG. 24) defined in the ski body150. As in the ski assembly100, the ski runner106has a body220including a rear wall222, a front wall224, a ground engaging bottom edge226and wearbars228. The front and rear walls224,222extend vertically and parallel to one another. The ski runner106is operatively connected to the ski102via the ski runner adjustment assembly800which is used to move the ski runner106in the slot702to change an amount by which the ski runner106extends below the ski102.

As in the ski assembly100, the ski assembly700has two wheels including: a front wheel110and a rear wheel112. The front and rear wheel frames158,160of the ski assembly100are however omitted from the ski assembly700.

With reference toFIGS. 21, 23, 24 and 26, a flange740extends upwards from the upper surface of the ski body150around the front end of the slot702. The flange740defines a channel742extending vertically and facing rearwardly. The channel742is formed continuously with the front end of the slot702and extends vertically upwards therefrom. The channel742has a C-shaped cross-section when viewed from a top or bottom as inFIGS. 21, 23 and 24. The C-shaped channel742has a front wall744extending vertically and laterally and a widened portion746. The front wall224of the ski runner106is received in the channel742. Another flange750extends upwards from the upper surface of the ski body150around the rear end of the slot702. The flange750defines a channel752extending vertically and facing forwardly. The channel752is formed continuously with the rear end of the slot702and extends vertically upwards therefrom. Similar to the channel742of the front flange740, the channel752has a C-shaped cross-section as seen best inFIGS. 21 and 24. The C-shaped channel752has a rear wall754extending vertically and laterally and a widened portion756. The rear wall222of the ski runner106is received in the channel752. The widened portions746,756, improve the liberty of movement of the ski runner106in the channels742,752.

With reference toFIGS. 21, 23 and 26, the ski assembly700includes a pair of walls710extending vertically upwards from the upper surface of the ski body150. The walls710extend generally longitudinally and are disposed between the walls188. The left wall710has a central portion712that extends parallel to the longitudinal centerline156on a left side of the ski runner106and the ski leg102. A front portion714of the left wall710extends parallel to the longitudinal centerline156and is disposed longitudinally forward of the front flange740. A rear portion716of the left wall710extends parallel to the longitudinal centerline156and is disposed longitudinally rearward of the rear flange750. Each of the front and rear portions714,716of the left wall710is disposed laterally inwardly of the central portion712. The front portion714is connected to the central portion712by a front connection portion which extends forwardly and laterally inwardly from the central portion712and the rear portion716is connected to the central portion712by a rear connection portion which extends rearwardly and laterally inwardly from the central portion712. The right wall710is similar to a mirror image of the left wall710and as such will not be described again herein. As can be seen inFIG. 23, the bolt126pivotally connecting the ski102to the ski leg104extends through the central portions712of both walls710. It is contemplated that the right wall710could be different from a mirror image of the left wall710.

With reference toFIGS. 23 and 26, the front wheel110is disposed between the front portions714of the left and right walls710and rotatably mounted thereto by a front axle724extending laterally through the front portions714. A portion of the front wheel110below the front axle724is received in a recess760formed in the ski body150. The recess760is shaped to be complementary to the front wheel110. As shown inFIG. 25, the front wheel110, is mounted to the walls710such that the lower portion116of the front wheel110extends through a front aperture762defined in the central keel152and is disposed below the bottom120of the ski body150. The rear wheel112is similarly disposed between the rear portions716of the left and right walls710and rotatably mounted thereto by a rear axle726extending laterally through the front portions714. A portion of the rear wheel112below the rear axle726is received in a recess770formed in the ski body150. The recess770is shaped to be complementary to the rear wheel112. As shown inFIG. 25, the rear wheel112is mounted to the wall710such that the lower portion118of the rear wheel112extends through a rear aperture772defined in the central keel152and is disposed below the bottom120of the ski body150. The walls710are removably mounted to the ski body150so that the wheels110,112can be installed between the walls710before the assembly of wheels110,112and walls710is mounted to the ski body150. In the illustrated implementation, the walls710are removably mounted to the ski body150by the bolt126.

The ski runner adjustment assembly800will now be described with respect toFIGS. 22, 27 and 28. As mentioned above, the ski runner adjustment assembly800has some elements that are similar to the ski runner adjustment assembly108described above. The elements of the ski runner adjustment assembly800that are similar to those of the ski runner adjustment assembly108described above have been numbered with the same reference numerals and will not be described again in detail.

With reference toFIG. 22, in the ski runner adjustment assembly800, the knob356of the ski runner adjustment assembly108and its related components, such as the clicker364and the spring366, have been omitted. The ski runner adjustment assembly800instead includes an electric motor802for adjusting the position of the shaft320and thereby the ski runner106. The motor802is received in a housing804which is connected to the top portion of the housing300enclosing the shafts318and320. The electric motor802has an output shaft (not shown) that is operatively connected to the shaft318. The electric motor802can be activated so that the output shaft, and thereby the shaft318, is rotated clockwise or counter clockwise for raising or lowering the shaft320. The electric motor802is activated based on the position of a switch808(FIG. 27) that is connected to the handlebar70such that the rider may operate the switch808while riding.

With reference toFIG. 27, in the illustrated implementation, the switch808is a toggle switch having eight different positions810. One of the positions810corresponds to the ski runner106being in a raised position as inFIGS. 21 to 24with the bottom126being disposed above the lower portions116,118of the wheels110,112. The remaining seven positions810correspond to different lowered positions of the ski runner106where the bottom126of the ski runner106is disposed lower than the portions116,118of the wheels110,112. The driver of the snowmobile20can toggle the switch808to any one of the eight positions to cause the ski runner106to be placed in a corresponding position with respect to the wheels110,112. It is contemplated that the correspondence between the switch position810and the relative vertical positioning of the ski runner106with respect to the wheels110,112could be different than as described herein. It is contemplated that the number of positions810could be more or less than eight. At least one of the positions810corresponds to the ski runner106being in a raised position where the bottom126of the ski runner106is disposed vertically higher than the lower portions116,118of the wheels110,112such that the ground G is engaged by the lower portions116,118of the wheels110,112as shown inFIG. 22. At least one of the positions810corresponds to the ski runner106being in a lowered position where the bottom126of the ski runner106is disposed vertically lower than the lower portions116,118of the wheels110,112and engages the ground G as shown inFIG. 25.

As shown schematically inFIG. 22, the electric motor802and the switch808are each connected to an electronic control module850for controlling the position of the ski runner106. Although not shown, the electronic control module850is connected to the respective electric motors802of both the left and right ski assemblies800. The electronic control module850receives a signal from the switch808indicative of the position810of the switch808. The electronic control module850simultaneously activates the respective electric motors802of both the left and right ski assemblies800based on the position of the switch808.

As can be seen inFIG. 22, in the illustrated implementation, the ski runner adjustment assembly800includes a runner position sensor830which senses the position of the ski runner106. As an example, the runner position sensor830could be in the form of a linear potentiometer which is configured to be sensitive to the position of the screw342(FIG. 15) or another object fixed to the screw342and moveable therewith. As the screw342is indicative of the position of the ski runner106, the linear potentiometer would be sensitive to the position of the ski runner106. The runner position sensor830is connected to the electronic control module850for providing a signal thereto indicative of the current position of the ski runner106. Although not shown, the electronic control module850is connected to the respective runner position sensors830of both the left and right ski assemblies800.

With reference toFIG. 28, in the illustrated implementation, an indicator820is included in the display cluster80to provide a visual indication of the switch position810and the position of the ski runner106. The indicator820includes an array822of eight rectangles corresponding to the eight switch positions810, with one of the rectangles824being filled to indicate the current position of the ski runner106. When the toggle switch808is moved from a first switch position810corresponding to a current position of the ski runner106to a second switch position810corresponding to a desired position of the ski runner106, the rectangle on the indicator820corresponding to the second switch position810begins flashing. The rectangle corresponding to the second switch position810stops flashing and becomes filled once the ski runner106is disposed in the desired position corresponding to the second switch position810. As can be seen inFIG. 22, the indicator820is connected to the electronic control module850for receiving signals therefrom indicative of the positions of the ski runner106and the switch808.

Other implementations of the ski assembly are also contemplated. For instance, the ski assembly could include three wheels: front and rear wheels as in the ski assembly100and a central wheel as in the ski assembly500. In an alternative implementation, the ski assembly could include two wheels that are laterally offset from the longitudinal centerline of the ski and/or the ski runner. For instance, a front wheel could be connected to the ski on the front right side of the ski runner and a rear wheel could be connected to the ski on the rear left side of the ski runner, or vice-versa.

Modifications and improvements to the above-described implementations of the present may become apparent to those skilled in the art. For example, each ski assembly could be provided with more than one ski runner connected to the ski runner adjustment assembly. The foregoing description is intended to be exemplary rather than limiting. The scope of the present is therefore intended to be limited solely by the scope of the appended claims.