U.S. patent number 3,613,812 [Application Number 04/887,138] was granted by the patent office on 1971-10-19 for shock mounted skis for snowmobile.
This patent grant is currently assigned to Arctic Enterprises, Inc.. Invention is credited to Edgar E. Hetteen.
United States Patent |
3,613,812 |
Hetteen |
October 19, 1971 |
SHOCK MOUNTED SKIS FOR SNOWMOBILE
Abstract
Each spindle forming a part of the steering mechanism of the
snowmobile is connected to a ski through its spring mechanism and
is also connected through a lever arm extending along the
longitudinal axis of the ski by a shock absorber. The shock
absorber is pivotally connected to the lever arm which is secured
to the spindle at one end, and to the ski at the other end. The
shock absorber resists any changes in substantially vertical and
rotational motions of the ski with respect to the spindle. The ski
is stabilized against sudden impulses by the dampening action of
the shock absorber.
Inventors: |
Hetteen; Edgar E. (Thief River
Falls, MN) |
Assignee: |
Arctic Enterprises, Inc. (Thief
River Falls, MN)
|
Family
ID: |
25390514 |
Appl.
No.: |
04/887,138 |
Filed: |
December 22, 1969 |
Current U.S.
Class: |
280/25; 180/190;
280/21.1; 280/26 |
Current CPC
Class: |
B62M
27/02 (20130101); B62M 2027/026 (20130101); B62M
2027/025 (20130101) |
Current International
Class: |
B62M
27/02 (20060101); B62M 27/00 (20060101); B62b
013/12 (); B62m 027/02 () |
Field of
Search: |
;180/3-6
;280/8,9,10,11,12,13,14,16,17,21,25,26 ;244/108 ;267/31,18,8 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Johnson; Richard J.
Claims
What is claimed is:
1. A forward suspension system for snowmobiles, including:
a. snowmobile body means having bearing means extending
substantially vertically through the forward portion of said body
means;
b. spindle means having a vertically extending shaft portion
rotatably secured within said bearing means and having a lower
portion adapted for transverse rotational connection;
c. ski means disposed beneath said forward portion of said body
means;
d. spring means secured to said ski means for biasing said body
against substantially downward movement;
e. clevis means secured to the upper portion of said spring means
and being rotatably connected to said spindle means through a
transverse member permitting pivotal movement of said spring means
and said ski means with respect to said spindle means;
f. lever arm means extending outwardly from said spindle means and
normal to said transverse member;
g. securing means fixedly securing said lever arm means to said
spindle means and against rotation with respect thereto;
h. and shock absorber means connected to said lever arm means and
to said ski means adjacent one end thereof for dampening any sudden
impulses, said shock absorber means resisting any changes in
substantially upward and pivotal movement of said ski means.
2. The spring means set forth in claim 1 including:
i. a leaf spring assembly pivotally secured at one end thereof to
said ski means and slidably secured at the other end thereof to
said ski means, said clevis means being disposed at substantially
the midpoint of said upper portion of said spring means.
3. The structure set forth in claim 2 including:
j. an inverted U-shaped member secured to said ski means and
overlying one end of said leaf spring assembly, said shock absorber
means secured to said U-shaped member and overlying said leaf
spring assembly.
4. A ski suspension system for snowmobiles comprising:
a. a pair of skis transversely disposed beneath the forward portion
of the snowmobile;
b. a pair of spring mechanisms, each of said pair of spring
mechanisms being secured to one of said pair of skis, said spring
mechanisms biasing the front part of said snowmobile against
substantially downward movement;
c. a pair of clevis members, each of said pair of clevis members
secured to the upper portion of one of said pair of spring
mechanisms;
d. a pair of spindle members, each of said pair of spindle members
rotatably secured to one of said pair of clevis members about an
axis transverse to the longitudinal direction of said skis, said
spindle members including a vertically extending shaft rotatably
secured to said forward portion of the snowmobile and a lever arm
extending outwardly along the longitudinal direction of said skis;
e. and a pair of shock absorbers, each of said pair of shock
absorbers connected to a distinct one of said pair of skis and to a
distinct one of said lever arms of said spindle members and
operative to control the vertical and rotational motions of said
pair of skis with respect to said spindle members.
Description
This application relates to the field of snowmobile suspension
systems and more particularly to shock absorbers used with the skis
on snowmobiles.
It has been found that during the operation of a snowmobile, there
are occasions when the snowmobile moves rapidly over a small mound
or mogul and upon reaching its crest, the machine is propelled into
the air and in so doing, the compression of the springs aids in the
upward movement of the snowmobile. Additionally, the skis have a
tendency to rotate about their spindles disposed at the upper
portion of the spring mechanisms. Thus, there is a substantially
vertical movement imparted to the skis and a rotational movement.
It is also found that when moving over generally open country, or
open terrain, that the skis produce a certain amount of "chatter"
due to the manner in which they have been secured to the steering
mechanism.
Each of the undesirable features just set forth is overcome by the
present invention wherein the vertical movement of the snowmobile
with respect to the skis and the rotational movement of the skis
with respect to the spindle is controlled through a dampening
action. Shock absorbers are secured between the forward portion of
the ski and a lever arm which is fixedly secured to the spindle or
shaft connected to the steering mechanism. Upon compression of the
springs, or rotation of the ski with respect to its pivotal member
on the spring mechanism, the shock absorber tends to dampen or
smooth out any sudden change in movement and thus produce a much
smoother operation of the skis which results in a smoother and more
comfortable ride. The problems just enumerated are quite prevalent
when the snowmobile is operated at a high speed.
It is therefore a general object of this invention to provide a
dampening action to all forms of movement in the skis of a
snowmobile with respect to the snowmobile body.
It is still a further object of this invention to provide dampening
action for all forms of movement of the skis of a snowmobile
regardless of the type of springs being used.
It is still another object of this invention to provide a shock
absorber for skis used on snowmobiles dampening both translational
and rotational motions of the skis.
It is a further object of this invention to provide a shock
absorber for skis used on snowmobiles in which the shock absorber
may be secured to the forward or rear portion of the skis.
These and other objects and advantages of the invention will more
fully appear from the following description, made in connection
with the accompanying drawings, wherein like reference characters
refer to the same or similar parts throughout the several views,
and in which:
FIG. 1 is a perspective view of a snowmobile showing an embodiment
of the invention;
FIG. 2 is a partial elevation view of a ski component showing
additional detail of one embodiment of the invention;
FIG. 3 is a partial elevation view in section showing the
relationship of a lever arm secured to a spindle member;
FIG. 4 is a partial elevation view of a ski component showing
additional detail of another embodiment of the invention; and
FIG. 5 is a partial elevation view showing the relationship of
another lever arm secured to the spindle means.
Referring to FIGS. 1 through 3, a snowmobile 10 is shown having a
body portion 11 and a tread 12 which supports the rear portion of
the snowmobile and produces the means for propelling the
snowmobile. At the forward portion of body 11 is a pair of skis 13
and 14. While the details of the invention are disclosed
particularly with respect to ski 14, it will be understood that ski
13 includes the same type of mechanism. A pair of springs 15 and 16
are secured respectively to skis 13 and 14 by a pivotal connection
at the rear thereof, pivotal member 17 being shown in connection
with ski 14. The springs 15 and 16 are secured to the front of the
skis in a slidable arrangement through the use of a pair of
inverted U-shaped members 20 and 21 which hold the ends of springs
15 and 16 in place and permit a longitudinal sliding action. Member
21 has an upstanding U-shaped member 22 secured thereto by suitable
means such as welding and a shock absorber 23 is connected thereto
through the use of a pin 24. Another clevis member 25 is secured to
spring 16 at its upper portion and in particular at its midpoint by
suitable means such as bolts 26. A spindle member 27 in the form of
an inverted "T" has an upstanding shaft member 28 which is
generally splined at the end thereof for connection to a steering
mechanism, the stem portion or vertically extending shaft member 28
being secured within a bearing 30 that is fixedly held to the body
11. A crossbar portion 31 forming the crossbar of the inverted
T-shaped member is secured transversely between the upstanding lugs
of clevis member 25 by passing a bolt or pin 32 through a bore 33
formed in member 31. In other words, bore 33 is transversely
oriented to the longitudinal axis of ski 14. Suitably secured to
spindle member 27 at a position adjacent cross bar member 31, is a
lever arm 34 that is shown in section in FIG. 3. Lever arm 34 may
be welded to insure that it is fixedly held in place. An arm 35
extends upwardly from shock absorber 23 and is connected to lever
arm 34 by suitable means such as a machine bolt 36. Arm 35 is
connected to the shock absorber piston member.
It will be apparent that ski 14 may be turned and that arm 35 which
is connected to the piston within the shock absorber will not be
materially affected. However, upon compression of spring 16, it
will be noted that piston arm 35 will be directed inwardly to
produce a dampening action for any sudden impulse or vertical
movement of ski 14 with respect to body 11. Additionally, because
pivot bolt 32 permits clevis member 25 to pivot about member 32, it
will be seen that there is a relative motion created between lever
arm 34 and ski 14 thus changing the length of piston arm 35 to
again produce a dampening of any sudden impulses or rotational
movement of ski 14. Therefore, both a pitching and vertical motion
are dampened through the use of the shock absorber to held
stabilize ski 14 and the same mechanism of course, would apply to
ski 13 and the counterparts just mentioned.
An alternate embodiment is shown in FIGS. 4 and 5 in which a
U-shaped clevis member 40 is secured adjacent the front edge of
spring 16 and shock absorber 23 is secured to member 40 through
suitable means such as a pin 42. A shaft 43 passes through a pair
of bores formed in clevis member 25 and through bore 33 of member
31. A pair of pins 44 and 45 are used to secure member 31 to shaft
43 by drilling holes through member 31 and 43 to pin the shaft 43
to the crossbar 31 of the T-shaped member 27. Thus, shaft 43 does
not turn with respect to spindle member 27. It will of course be
recognized that any other suitable means may be used in place of
pins 44 and 45 to secure the two members against movement with
respect to each other. A splined portion 46 is formed on the end of
shaft 43 and a lever arm 47 is secured thereto. Suitable means such
as a pin or bolt 48 is used to pivotally secure piston arm 35 to
lever arm 47. It will thus be seen that any vertical movement of
ski 14 with respect to body 11 will again cause movement of piston
arm 35 and any pitching movement of clevis member 25 and ski 14
about shaft 43 will again produce a movement of piston arm 35.
Thus, it will be seen that another embodiment of the invention has
been disclosed.
From the disclosure set forth herein, it will be seen that a new
and novel means has been provided to dampen any sudden impulses or
movements of the skis of a snowmobile which are caused by hitting
an obstruction or being propelled through the air so that the skis
are free to rotate about their connections with the spindle members
of the steering mechanism. It will be thus seen that a much
smoother and more stable ride is a result.
It will, of course, be understood that various changes may be made
in the form, details, arrangement and proportions of the parts
without departing from the scope of the invention which consists of
the matter shown and described herein and set forth in the appended
claims.
* * * * *