CRAMPONS ET SUPPORTS DE TRACTION POUR MOTONEIGE

SNOWMOBILE TRACTION STUD AND MOUNTING

Abrégé anglais

ABSTRACT.
An improvement in a snowmobile having laterally- spaced,
ground-engaging flexible traction bands with supporting rails
positioned intermediate the bands. Transversely-extending chan-
nel bars are secured integrally with the traction bands. Trac-
tion lugs are positioned in the channel bars and extend trans-
versely 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.
1.

Revendications

P-301
The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
1. An integral lug for increasing the traction of a
snowmobile track comprising a bottom with an upwardly extending
wall extending about the periphery of said bottom, said lug being
elongated so that said wall includes end portions interconnected
by longer side portions, and spike portions extending from said
side portions of said wall.
2. A lug as set forth in claim 1 including a pair of
holes in said bottom for receiving fasteners.
3. A lug as set forth in claim 2 including one of
said spike portions extending from one of said side portions of
said wall and two of said spike portions extending from the
other of said side portions of said wall.
4. A lug as set forth in claim 3 wherein said one
spike portion is disposed at the longitudinal center of said
lug and said two spike portions are disposed symmetrically on
opposite sides of said longitudinal center.

Description

~,~t~r)~
THE SPECIFICATION.
.
This invention relates to snowmobiles having ground-engag-
ing track bands spaced transversely and having supprtlng rails
therebetween which are integral with the frame. Channel bars ex- -
tend trans~ersely of the track bands and are lntegral therewith,
and are spaced lon~ltudinally of the bands.
Thls invention supplies a novel traction lug lntegral 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 relatlve to the supporting rails. The traction lugs
are provided with spikes or teeth to enhance the engagement with
the surface Or travel.
An ob~ect of thls invention ls to provide a means of preven-
tlng undue dlstortlon of the channel bars where they engage the
supportlng rails~ and to provlde addltlonal ground-engaglng means.
Another ob~ect ls to provlde traction lugs having inserted
polnts whlch are spaced longltudlnall~ ln the lug.
Further ob~ects and advantages of this lnvention wlll become
apparent from a consideratlon of the followlng detailed descrlp-
tlon. It ls, however, to be under~tood that the invention ls not
to be ~itmited(~to the detalls dlsclosed, but includes all such varl-
atlons as fall wlthln the spirlt of the invention.
Referrlng to the drawlngs:
Flg. 1 ls a vlew of a portlon of the track bands looklng up-
wardly, and normal to the plane thereof, and embracing the trac-
tlon lugs of thls inventlon.
Fig. 2 is a section taken at 2-2 of Fig. 1.
Flg. 3 ls a section taken at 3-3 of Flg. 1. `
Flg. ~ shows a modlfled form of the traction lug.
Flg. 5 ls a pro~ectlon of Flg. ~ with parts removed.
Referring agaln to the drawlngs:
...
2. ~
. . .

The traction band comprises a central band 10 and outer
bands 12 and 14, which bands are spaced laterally, and travel in
the direction indicated 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 snowmobile is provided with fore-and-aft~
exkending 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 ~n Figs. 1 and 2. Non~metallic shoe por-
tlons 22 are longitudinally-lnte~ral wlth the lower portion of
ralls 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, comprlslng central band 10 and outer bands
12 and 1~ are secured inte~rally as a unit by a plurality of chan- -
nel bars 24, in this lnstance, only one belng shown, and which bars
are dlrected tran~versely of the tractlon band, and spaced apart
long~tudlnally along the traction band. Channel bars 24 are secured
integrally to tractlon bands 10, 12 and 14 by suitable bolts or
rlvets 26, thNs provlding a unitary tracX-band assembly. Channel
bars 24 J~idably engage the lower surface of shoe portlons 22
when the snowmoblle is in motion.
Tractlon lugs 28 are posltioned ln the channels of the bars
24 so as to extend transversely of shoe portlons 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 su~-
ficiant rigldity. Walls 30 termlnate ln downwardly- directed spike
portions 3~ which e~tend below the wallq of channel bars 24, as
shown in Figs. 2 and 3. One of the walls 30 termlnates downwardly
in a single splke and the other wall terminates in a palr of splkes
positloned longltudinally, and symmetrically wlth respect to the
single spike.
3-
... . . - . . .- - ., -

`` 10'~3505
1 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 com-
prising a bar 40 having laterally-spaced studs 42 threadedly
inserted 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 directed
symmetrically with respect to the centers of rails 20. Thereforç,
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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