Traction enhancement system

A traction enhancement system (10) for a snowmobile (12) that includes a front plate member (14) and deflection plates (16) mounted ahead of the snowmobile body (18) for deflecting and compressing fresh, ungroomed snow to enhance traction, startability, and stability of the snowmobile in heavy and rough snow conditions. The front plate member (14) comprises an upper screen (40) offset ahead of a lower screen (42), with both screens being attached to the bumper (36) to angle downward toward the tail section (28) of the snowmobile (12). Each deflection plate (16) is bent along a longitudinal axis and mounted to the tip (32) of the skies (30) to deflect snow to either side of the skies (30). The front plate member (14) and the deflection plates (16) are slidably engaged within their respective receiving tubes (61) and (98), which are attached to the snowmobile (12) to facilitate quick and easy attachment and detachment.

TECHNICAL FIELD 
The present invention pertains to devices for improving traction in the 
snow, and, more particularly, to a traction enhancement system for a 
snowmobile that improves traction, stability, and startability in deep 
snow and other unusual conditions. 
BACKGROUND OF THE INVENTION 
Snowmobiles are a common means for traveling in or on snow. Typically, 
snowmobiles are small vehicles with ski-like runners in front used to 
steer the vehicle and tank-like treads in back for propelling the vehicle 
across the snow. To facilitate passage of the snowmobile through deep 
snow, groomed trails are frequently formed, especially in the back country 
and in restricted areas. However, continual use of these trails results in 
the snow becoming compacted and grooved, making passage more difficult and 
the ride uncomfortable. Consequently, snowmobile riders will attempt to 
ride off the trail in fresh snow. Furthermore, it sometimes becomes 
necessary to ride in fresh snow where no trails have been formed, such as 
immediately after or during a snowfall or to travel to a wilderness area. 
One difficulty in riding in deep snow is that the snowmobile is capable of 
only traveling through snow of a certain depth. When fresh snow is more 
than a foot deep, traction is severely reduced, making it difficult to 
initiate movement and maintain stability. 
Although there are a number of devices for grooming snowmobile trails, 
there does not exist any device that attaches to the front of the 
snowmobile for improving traction in heavy or deep snow. For instance, 
U.S. Pat. No. 3,884,498, issued to Cote, Jr., on May 20, 1975 discloses a 
snowmobile trail sweep that is essentially a precurved flap attached to 
the rear of the snowmobile to smooth the snow behind the vehicle as it 
travels over a trail. U.S. Pat. No. 4,057,916, issued to Roemer on Nov. 
15, 1977, discloses a snowmobile trail leveler having a multi-blade 
rotating member positioned between a traction tread and a pair of 
forward-mounted skis for leveling bumps or raises in a snowmobile trail. 
Similarly, U.S. Pat. No. 4,127,949, issued to Sabrowsky et al. on Dec. 5, 
1978, teaches an apparatus designed to break up a wavy and rutted 
snowmobile trail, including packed and icy snow, thus smoothing out an 
already existing trail. None of these references teaches or suggests 
attaching a device to the front of a snowmobile for deflecting and 
compressing snow ahead of a snowmobile. 
SUMMARY OF THE INVENTION 
The present invention is directed to a traction-enhancing system for a 
snowmobile. The system includes a snowmobile having a pair of 
forward-mounted skis with upwardly curving tips and a rear-mounted track. 
A first plate member is mounted between the pair of skis and forward of 
the snowmobile track for pushing and compressing snow. A pair of second 
plate members are each mounted on the tip of a single ski for deflecting 
and compressing snow ahead of the ski. 
In accordance with another aspect of the present invention, the first plate 
member comprises a first plate and a second plate, with the first plate 
being positioned above and forward of the second plate. Ideally, the first 
and second plates are positioned at an angle such that they angle downward 
toward the rear of the snowmobile. 
In accordance with yet another aspect of the present invention, the first 
and second plates and the pair of second plate members are all formed of 
metal mesh plate material. However, it is to be understood that other 
material of suitable strength and functionality may be used without 
departing from the spirit and scope of the invention. 
In accordance with a further aspect of the present invention, each of the 
second plate members are bent along a longitudinal axis such that when 
mounted on the ski, snow is deflected laterally to either side of the ski. 
As will be readily appreciated from the foregoing description, the present 
invention provides a traction enhancement system for a snowmobile that 
enables the snowmobile to travel in deep and fresh snow. Because the snow 
is deflected away from the front skis and compressed forward of the track, 
traction is improved and the startability of the snowmobile in deep snow 
and other unusual conditions is enhanced. In addition, stability is 
increased, thereby increasing safety for the rider and other riders in 
close proximity. Furthermore, all of the plates are easily attached and 
detached from the snowmobile. The system also provides stability in 
different types of terrain, for example, while traversing side hills, 
traveling up or down hills, and while making turns. The present system is 
not designed for and has no use on pre-existing trails. If this type of 
travel is desired, the rider can easily and quickly detach the plates from 
the brackets, although preferably they will remain in place.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
The representative embodiment illustrated in FIG. 1 is directed to a 
traction enhancement system 10 comprising a snowmobile 12, a front plate 
member 14, and a pair of forward-mounted deflection plates 16. With 
respect to the snowmobile 12, since these vehicles are readily 
commercially available, it will not be described in detail herein. 
Briefly, the snowmobile 12 includes a body 18 having a nose cone 20, 
windshield 22, handlebars 24, a seat 26, and a tail section 28. The 
snowmobile 12 is supported above the snow by a pair of spaced-apart 
parallel skis 30 having upwardly curved tips 32. The drive means typically 
consists of a gasoline powered engine (not shown) that drives a track 34 
mounted under the seat 26 and tail section 28. A bumper 36 is mounted on 
the leading edge of the nose cone 20. 
Most snowmobiles are designed to operate on groomed trails or in shallow 
freshly-fallen snow. Operating a snowmobile in deep snow off of a groomed 
trail is unsafe because the track 34 has difficulty achieving traction and 
the forward skis 30 do not provide enough stability, especially while 
traversing the side of a hill, traveling up or down a hill, and while 
making turns. The traction enhancement system 10 formed in accordance with 
the present invention overcomes these disadvantages and permits operation 
of the snowmobile 12 in snow of substantial depths. The present invention 
accomplishes this by having a front plate member 14 mounted ahead of the 
snowmobile body 18 and a pair of deflection plates 16 mounted on the tips 
32 ahead of the skis 30 to deflect the snow and compress it, thus forming 
a rough trail over which the snowmobile 12 can then be ridden. 
As shown more clearly in FIGS. 2 and 3, the traction enhancement system 10 
comprises two main components, the front plate member 14, illustrated in 
disassembled form in FIG. 2, and a pair of deflection plates 16, 
illustrated in disassembled form in FIG. 3. Referring to FIG. 2, the front 
plate member 14 is shown along with the attachment hardware 38. The front 
plate member 14 is comprised of two offset mesh screens, an upper screen 
40 and a lower screen 42. Both screens 40 and 42 are attached to a left 
frame member 44 and a right frame member 46. Ideally the upper and lower 
screens 40 and 42 are formed of wire mesh material having openings 47 
therein. Both screens 40 and 42 are of the same size, being approximately 
11 inches high and 17 inches long. The left and right frame members 44 and 
46 are formed of box tube iron or other suitable metal material such that 
the upper and lower screens 40 and 42 can be attached thereto by welding 
or other suitable method. When the upper screen 40 is so attached to the 
frame members 44 and 46, it will be offset several inches forward of the 
lower screen 42. Furthermore, the left and right frame members 44 and 46 
are so formed that both screens 40 and 42 will angle downward toward the 
tail section 28 of the snowmobile 12 when the front plate member 14 is 
attached to the snowmobile 12. 
The left and right frame members 44 and 46 have lower angled rails 48 and a 
pair of upper horizontal rails 50 that are offset by a vertical rail 52. 
The forward portion 54 of the upper horizontal rails 50 is attached to the 
lower angled rails 48 at its forward most point 56 and a vertical support 
rail 58 attaches the upper horizontal rails 50 to the lower angled rails 
48 at the approximate midpoint. A vertical attachment rail 60 depends 
downward from the rearward end of the upper horizontal rails 50 to form an 
attachment point. 
The attachment hardware 38 includes a pair of attachment plates 64 for each 
frame member 44 and 46, comprising a front attachment plate 66 and a rear 
attachment plate 68. Four bolts 70 are used to attach each pair of plates 
64 to the bumper 36 of the snowmobile 12. A retaining pin 72 is used to 
hold the vertical attachment rail 60 in engagement with the front 
attachment plate 66, as will be described more fully below. 
The deflection plates 16 and their attachment hardware 74 will now be 
described in more detail in conjunction with FIG. 3. As illustrated 
therein, each deflection plate 16 is formed of metal mesh material having 
openings 76 formed therein. Each deflection plate 16 has an approximate 
rectangular shape and is bent along its longitudinal axis at an angle that 
is preferrably between 75 and 90 degrees. A single frame member 78 is 
attached to each deflection plate 16 along the longitudinal axis. The 
frame member 78 includes a longitudinal rail 80 that is attached to the 
deflection plate 16 and a corner rail 82 that is attached to the 
longitudinal rail at an angle such that when the frame member 78 is 
attached to the tip 32 of the ski 30, the deflection plate 16 will be 
angled downward toward the tail section 28 of the snowmobile 12. A brace 
rail 84 is also attached to the longitudinal rail 80 and the corner rail 
82 for reinforcement. The free leg 86 of the corner rail 82 is used to 
attach the deflection plates 16 to the snowmobile 12. 
Also illustrated in FIG. 3 is the attachment hardware 74 that includes a 
corner bracket 88 and a pair of clamps 90 used to attach the corner 
bracket 88 to a mounting rail 92 (shown more clearly in FIG. 1) that is 
attached to the tip 32 of the ski 30. A pair of resilient cushions 94 
prevent scratching of the brackets 88 and rails 92 by the clamps 90. The 
retaining pins 96 maintain the free leg 86 in engagement with the corner 
bracket 88, as will be described in more detail below. Each corner bracket 
88 further includes a receiving tube 98 formed on one leg thereof to 
slidably receive the free leg 86 of the frame member 78. 
Referring next to FIG. 4, the construction and operation of the traction 
enhancement system 10 will now be described. For the attachment of the 
front plate member 14, the rear attachment plate 68 is placed behind the 
bumper 36 and the front attachment plate 66 is aligned in front of the 
rear attachment plate 68 on the front side of the bumper 36. The four 
bolts 70 are inserted through holes in the attachment plates to urge them 
together to grip the bumper 36. Next, the front plate member 14 is brought 
to a position where the vertical attachment rails 60 are aligned with a 
receiving tube 61 that is formed on the front attachment plates 66. The 
vertical attachment rail 60 is then slidably engaged within the receiving 
tube 61 and retained in position by inserting the retaining pin 72 through 
openings in the receiving tube 61 and the vertical attachment rail 60. The 
front plate member 14 is easily removed by pulling out the retaining pins 
72 and lifting the vertical attachment rails 60 out of the receiving tubes 
61. Preferably the attachment plates 64 remain in position on the bumper 
to facilitate quick and easy attachment and removal of the front plate 
member 14. 
The deflection plates 16 are similarly mounted to the skis 30. First, the 
corner brackets 88 are attached to the mounting rails 92 on the ski tip 32 
as illustrated, with the receiving tube 98 being vertically oriented. The 
resilient cushions 94 are wrapped around the mounting bracket 92 and the 
corner bracket 88, and then the clamps 90 are placed around the resilient 
cushions 94 and tightened. Each deflection plate 16 is brought to the 
respective corner bracket 88 and the free leg 86 is slidably engaged 
within the receiving tube 98 on each corner bracket 88. The deflection 
plates 16 are retained within the receiving tube 98 by sliding the 
retaining clips 96 through openings in the receiving tube 98 and the free 
leg 86. As with the front plate member 14, the deflection plates 16 may be 
easily and quickly removed by pulling out the retaining clips 96 and 
lifting the free legs 86 clear of the receiving tubes 98. Preferably the 
corner brackets 88 will remain attached to the mounting brackets 92 on the 
ski tips 32 to facilitate quick and easy attachment and removal of the 
deflection plates 16. 
In operation, the upper and lower screens 40 and 42 and the deflection 
plates 16 contact snow as the snowmobile 12 is propelled forward by the 
track 34 such that the snow will be deflected downward and compressed by 
the front plate member 14 and deflected to either side of the skis 30 by 
the deflection plates 16. With this traction enhancement system 10, a 
rough trail is pregroomed in the snow ahead of the snowmobile 12 to enable 
the track 34 to start the snowmobile 12 moving and enhance traction. In 
addition, the deflection plates 16 allow the skis to stabilize the 
snowmobile 12, especially on hills and when making turns. 
While a preferred embodiment has been illustrated and described, it is to 
be understood that various changes may be made therein without departing 
from the spirit and scope of the invention. For instance, the upper and 
lower screens 40 and 42 and the deflection plates 16 may be formed of 
material other than metal mesh screens, such as very strong lattice 
woodwork or a composite plastic. Furthermore, it is contemplated that the 
mounting angle of the front plate member 14 and the deflection plate 16 
can be mechanically varied by a rider as the snowmobile 12 is being driven 
across the snow to achieve the best traction and stability under different 
conditions. Thus, the scope of the invention is to be limited only by the 
claims that follow.