CRAMPON DE TRACTION POUR MOTONEIGE

SNOWMOBILE TRACTION STUD AND MOUNTING

Abrégé anglais

ABSTRACT OF THE DISCLOSURE
An improvement in a snowmobile having laterally-
spaced, ground-engaging flexible traction bands with supporting
rails positioned intermediate the bands. Transversely-extending
channel bars are secured integrally with the traction bands.
Traction lugs are positioned in the channel bars and extend
transversely and symmetrically relative to the space between the
bands. The lugs serve to engage the surface of travel and to
provide a rigid support against undue distortion of the channel
bars, and to provide increased tractive force.

Revendications

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
1. A snowmobile comprising; a fixed longitudinally
extending track-supporting rail, a longitudinally-propelled
track including laterally-spaced plural bands of flexible
material defining a longitudinal gap therebetween, said rail
being positioned in said gap, a bar extending transversely
across said track and secured to said bands, a transversely
extending traction lug extending across said gap, said lug
having at least one spike portion directed downwardly, and secur-
ing means securing said lug to said bar on opposite sides
of said rail.
2. A snowmobile as set forth in claim 1 wherein said securing
means includes a pair of fasteners extending through said lug
and through said bar, said fasteners being disposed on
opposite sides of said rail.
3. A snowmobile as set forth in claim 2 wherein said
fasteners comprise threaded bolts and nuts.
4. A snowmobile as set forth in claim 2 wherein said
fasteners extend through said respective bands.

Description

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1 This application is a divisional of application serial
number 285,616, filed August 29, 1977.
This invention relates to snowmobiles having ground- ~-
engaging track bands spaced transversely and having supporting
rails therebetween which are integral with the frame. Channel
bars extend transversely of the track bands and are integral
therewith, and are spaced longitudinally of the bands.
This invention supplies a novel traction lug integral with
the channel bars, and which lug bridges the space between the
bands, and resists lateral forces that would tend to distort the
channel bars relative to the supporting rails. The traction lugs
are provided with spikes or teeth to enhance the engagement with
the surface of travel.
An object of this invention is to provide a means of pre-
venting undue distortion of the channel bars where they engage
the supporting rails, and to provide additional ground-engaging
means.
Another object is to provide traction lugs having in-
serted points which are spaced longitudinally in the lug.
Further objects and advantages of this invention will
become apparent from a consideration of the following detailed
description. It is, however, to be understood that the invention
is not to be limited to the details disclosed, but includes all
such variations as fall within the spirit of the invention.
Referring to the drawings:
Fig. 1 is a view of a portion of the track bands looking
upwardly, and normal to the plane thereof, and embracing the trac-
tion lugs of this invention.
Fig. 2 is a section ta}cen at 2-2 of Fig. 1.
Fig. 3 is a section taken at 3-3 of Fig. 1.
Fig. 4 shows a modified form of the traction lug.
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1084563
1 Fig. S is a porjection of Fig. 4 with parts removed.
Referring again to the drawings:
The traction band comprises a central band 10 and outer
bands 12 and 14, which bands are spaced laterally, and travel in
the direction ïndicated by arrow 16 of Fig. 1. Bands 10, 12 and
14 are of fabric-reinforced rubber or similar suitable material,
and which are provided with transverse "ribbing" 18 to improve
traction.
The frame of the sno~mobile is provided with fore-and-aft
extending track-supporting rails which are integral with the
frame and indicated as 20; being laterally spaced intermediate
the bands 10, 12 and 14, as shown in Figs. 1 and 2. Non-metallic
shoe portions 22 are longitudinally-integral with the lower
portion of rails 20, and serve as a friction-reducing supporting
surface for the track band assembly, as the latter slides in the
direction indicated as 16 of Fig. 1.
The traction band, comprising central band 10 and outer
bands 12 and 14 are secured integrally as a unit by a plurality
of channel bars 24, in this instance, only one being shown, and
which bars are directed transversely of the traction band, and
spaced apart longitud;nally along the traction band. Channel
bars 24 are secured integrally to traction bands 10, 12 and 14
by suitable bolts or rivets 26, thus providing a unitary track-
band assembly. Channel bars 24 slidably engage the lower surface
of shoe portions 22 when the snowmobile is in motion.
Traction lugs 28 are positioned in the channels of the
bars 24 so as to extend transversely of shoe portions 22, and
symmetri`cally therewith, Lugs 28 are of steel and of the cupped
shape as shown, and have walls 30 and a bottom panel 32 which
provides sufficient rigidity. Walls 3Q terminate in downwardly-
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I directed spike portions 34 which extend below the walls ofchannel bars 24, as shown in Figs. 2 and 3. One of the walls 30
terminates downwardly in a single spike and the other wall
terminates in a pair of spikes positioned longitudinally, and
symmetrically with respect to the single spike. Lugs 28 are
properly hardened so as to resist wear, and are secured in the
channel bars 24 and bands 10, 12 and 14 by bolts 36 and nuts 38.
Figs. 4 and 5 concern a modified traction lug comprising
i a bar 40 having laterally-spaced studs 42 threadedly inserted
; 10 therein, and having points to provide sufficient traction.
Bolts 44 pass through bar 40, channel bar 24 and bands 10, 12
and 14. Nuts 46 secure bolts 44 in the assembly.
The advantages inherent in the above-described improve-
ments with respect to snowmobiles is evident upon reference to
Fig. 2. The upwardly-directed forces applied during operation
of the snowmobile are indicated by the arrows F, and are d rected
symmetrically with respect to the centers of rails 20. Therefore,
any tendency for upward distortion of the track laterally of
the rails 20 will be held to a minimum.
The above being a complete description of an embodiment
of the invention of which an exclusive property or privilege is
claimed, is as follows.
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