Note: Descriptions are shown in the official language in which they were submitted.
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The present invention generally relates to suspension
means and more particularly, an improved shock-absorbing wheel
suspension assembly.
Many types of shock absorbers have been devised ~or
vehicles. Most such shock absorbers are complicated in construction
and are utilized as separate devices in addition to wheel axles and
other components comprising the primary wheel suspension system for
the vehicle. Moreover, the shock absorbers normally absorb shocks
through the use of a single mechanism or mode of operation, e.g.
resilient compression in a single plane and are subject to con-
siderable wear and stress. Many smaller types of vehicles, such
as wheeled cots, stretchers and wheel chairs incorporate ineffec-
tive or literally no .shock-absorbing means whatsoever, although
shock dampening means would be desirab:le for the same.
United States Patent No. 3,057,642 discloses a novel
type of wheel suspension apparatus which incorporates directly
therein an improved shock absorhing means. This shock absorbing
means comprises a considerable number of interconnected components
carefully fitted together to cause shock absorption and force
dissipation by two separate mechanisms; namely, linear bending and
principally torsional stressing. However, the apparatus is some-
what complicated in construction and expensive to build and main-
tain. Accordingly, it would therefore be desirable to be able to
provide an improved unitary r simple shock absorbing wheel suspen-
sion assembly suitable for a wide variety of uses, which assembly
would be less complicated and less expensive to construct and main-
tain.
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BRIEF SUMMARY OF THE INVENTION
The improved shock absorbing wheel suspension assembly
of the present invention satisEies the Eoregoing needs.
The invention provides an improved shock-absorbing wheel
suspension assembly, said assembly comprising, in combination:
a. a rigid yoke having a generally upwardly extending neck and a
pair oE downwardly diverging hollow tubular sleeves connected to
the lower end of said neck, both of said sleeves being directed
either rearwardly or forwardly relative to said neck; b. a pair of
flexible resilient lever support arms, the upper ends of which
extend into said sleeves, the elongated middle portions of which
are generally parallel to each other and extend downwardly and in
the ~ame rearward or forward direction as said sleeves relative to
said neck and the lower ends of which arms are angled to approxi-
mat:e each other in and about horizontal plane; and c. a wheel
disposed between said lower ends with a central hub which receives
ancl holds said lower ends oE said arms in a fixed position relative
to s~id hubl whereby upward deElection of said wheel exerts flex-
ing and torquing of said arms to effect effective shock absorption
by said assembly.
The invention also provides an improved torsional shock
absorber assembly comprising: a. a pair of torsion arms; bu each
arm having a mid-portion, an upper extension and a lower extension;
c. said lower extension lying at substantially right angles to said
mid~portion; d. said upper extension lying at an angle other than
at a right angle to said mid-portion; e. said torsion arms being
disposed in said assembly so that said upper and lower extensions
are directed inwardly towards one another; and f. means to con-
tinuously confine said arm and upper and lower extenslons in asingle plane, including: (1) a rigid yoke adapted to be attached
to a vehicle and having a plurality of sleeves adapted to receive
said upper extensions while enabling rotational movement therein
of said upper extensions, and (2) a hub adapted to rotatably
retain a wheel therein and receive therein said lower extensions.
The assembly may include an upstanding stem connected to
the yoke neck and connectable to the underside of a vehicle body.
The yoke may be a simple unitary metal casting or the like and
each arm may be formed of a single rod of flexible steel or the
like. Thus, the assembly provides both suspension and shock-
absorb1n~ means in a simple inexpensive efficient construction.
The assembly can have the wheel located in front of or
behind the yoke and stem. Shocks transmitted to the vehicle body
during movement of the assembly, as a result of sudden upward
clisplclcements oE the wheel caused by road bumps, etc., are sub-
.~t~ntially and eEEectively dampened and absorbed primarily by
torsional stressing of the spring bars thernselves. Thus, the wheel
during such displacement travels upwardly in an arc carrying with
it the lower ends of the arms. The center of rotation for this is
located in about the point of which each lever arm enters its
associated sleeve. However, since the two sleeves are sloped
downwardly and away from each other, this wheel displacement also
simultaneously causes each arm to undergo twisting or torsional
stress. The combined flexing and torsion of the arms effectively
dampen and absorb the road shocks. To assist insertion of the
arms into the sleeves and limit the degree of rotation of the arms,
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each sleeve is cut away a predeterrnined amount at its lower end.
Further features of the assembly are set
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fo:rth in the following detailed description and ac-
companying drawings.
BRIEF DESCRIPTION OF THE DRi~WINGS
Figure 1 is a sche~a~ic.side elevation, partly
broken away, of a first preferred embQdiment~ of the
improved shock absorbing wheel suspension assembly
of the present invention showing the assembly attached
to the underside of a vehicle body, and also showing
the path of deflection of the wheel when subjected to
road shocks and the like;
Figure 2 is a schematic front elevation, partly
broken away and partly in section, of the assembly of
Figure l; and
Figure 3 is a schematic perspective view,
partly broken away, of a second preferred embodiment
of the improved shock absorbing wheel suspension
assembly of the present invention, showing the as-
semb].y attached to the underside of a vehicle body.
DETAILED DESCRIP~ION OF THE
PREFERRED EMBODIMENT
Now referring more particularly to Figures 1
and 2 of the accompanying drawings/ a first embodiment
of the improved shock-absorbing wheel suspension as-
sembly of the invention is schematically depicted therein.
Thus, assembly 10 is shown which comprises a yoke 12,
cylindrical stem 14, arms 1.6 and 18 and wheel 20 with
control hub 22. Also .shown is the underside of the
body portion 24 of a vehi¢le (not shown) bearing a
socket 26 into which the upper ends 28 of stem 14
is received, preferably for rotation.
The upper portion 30 of stem 14 may be cylindrical
and is vertical while the lower portion 32 thereof
is angled therefrom with the lower end 24 thereof in-
serted into a cavity 36 in the angled upper portion
or neck 38 of yoke 12 and releasably secured therein,
as by spring pins 40 and 42 ~Figure 13 or the like.
The lower portion 44 of yoke 12 comprises a
pair of hollow tubular sleeves 46 and 48 which extend
downwardly and rearwardly or forwardly from neck 38
at about a 90 angle, although other angles substantially
less than 180 are acceptable. Yoke 12 preferably is
forged or cast of a single rigid piece of s~eel or
moulded of a single piece of high strength plastic
or the like into a unitary body.
Sleeves 46 and 48 preferably diverge from
each other at about a 100 angle (Figure 2), although
other angles are also acceptable~ Sleeves 46 and 48
define central cylindrical passageways 50 and 52,
respectively, within which the upper ends 54 and 56
respectively of flexible resilient cylindrical lever
arms 16 ancl 18 are disposed. Preferably arms 16 and
18 are fabricated of high tensile strength steel rod
or the like. Ends 54 and 56 are preferably dampened
to meet in line and normal to each other and converge
within yoke 12 at the base of neck 38. Ends 54 and
56 are angled relative to the elongated middle portions
58 and 60 of arms 16 and 18, respectively, as shown
in Figure 2, which portions 58 and 60 are parallel to
each other. Rivets 62 and 64 or other means such as
screws, etc. (not shown), may be disposed through
the sleeve wall at the lower ends 66 and 68 of sleeves
46 and 48, respectively, to prevent ends 54 and 56
from sliding out of sleeves 46 and 48.
When viewed from the side (Figure 1), it can
be seen that portions 58 and 60 lie in the same angled
plane as sleeves 46 and 48 and thus extend downwardly
and rearwardly to lower ends 70 and 72 thereof. Ends
70 and 72 are angled to approximate each othex in the
horizontal plane and are releasably secured in opposed
ends of horizontal hub 22 of vertical wheel 20 by any
suitable means, such as for example, in eaçh instance,
a spanner 74 configured sleeve 76 and bearing and
race assembly 78~ The wheel 20 is thus free to rotate
around the axle formed of ends 70 and 72 of arms 16
and 18 while ends 70 and 72 remain in fixed relation
thereto.
When assembly 10 is secured to body 24, as
shown in Figure 1, wheel 20 is largely behind yoke
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12 with wheel 20 centered between sleeves 46 a~d 48
(Figure 2) and preferably in the same vertical plane
as stem 14 and neck 38. When body 24 is moved so that
wheel 20 rotates, shocks due to uneven ground, etc.,
which are transmitted to wheel 20 cause it to deflect
upwardly along an arc 80 (Figure 1) the center of
rotation of which is at about the lower ends 66 and
68 of sleeves 46 and 48. For example, wheel 20 can
be deflected to the position shown in dotted outline
in Figure 1. Ends 70 and 72 are connected thereto
and move therewith.
Ends 66 and 68 of sleeves 46 and 48 are cut
away in the areas dèsignated 82 and 84 in Figures
1 and 2 to facilitate initial insertion of ends 54
and 56 in sleeves 46 and 48 during construction of
assembly 10, and limit the angular rotation of arms ~
16 and 18. Linear flexing and bending of arms 16 and
18 occurs along the length of middle portions 58 and
60 thereof to absorb the deflecting force transmitted
thereto. Moreover, since ends 54 and 56 of arms 16
and 18 are angled away from the plane of rotation of
the portions 58 and 60 of arms 16 and 18 the described
linear flexing is accompanied by torsional stressing
or twisting o arms 16 and 18 in the area of the
juncture of ends 54 and 56 with middle portions 58
and 60 and for some distance therebeyond. This has
an additional deflection damping effect, further
absorbing and minimizing the shock transmitted through
assembly 10 to body 24. Since lower ends 70 and 72
are confined to the plane of arms 16 and ]8 and upper
ends 54 and 56, additional shock absorption takes
place by torsional stressing at the junction of lower
ends 70 and 72 and arms 15 and 18 respectively. Wheel
20 returns to its undeflected positon as arms 16 and
18 recoil from the deflecting force in each instance
for smooth movement of body 26. Accordingly, the
desired wheel suspension and effective shock absorbing
results are obtained with a simple durable assembly.
A modified version of assembly 10 is shown
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schematically in perspective view in Figure 3.
Components shown therein which are similar to those
of assembly 10 as shown in Figures 1 and 2 bear the
same numerals but are succeeded by the letter "a".
Thus, assembly lQa is shown which includes vertical
stem 14a connected to the body 26a and to a vertical
neck 38a of yoke 12a. Yoke 12a includes downwardly
and forwardly diverging sleeves 46a and 48a within
which are received upper ends 54a and 56a of resilient
flexible arms 16a and 18a, respectively, the middle
portions 58a and 60a of arms 16a and 18a, respectively,
being parallel to each other extending forwardly and
-terminating in lower ends 70a and 72a which are angled
into the horizontal plane so as to approximate each
other. Ends 70a and 72a are secured in opposite sides
of hub 22a for rotation of wheel 20a in a vertical
plane therebetween.
Thus, assembly lOa differs in construction
from assembly 10 only in that neck 38a is vertical
rather than angled, sleeves 46a and 48a do not have
cut-away portions on their lower ends, legs 16a and 18a
are directed forwardly rather than rearwardly and
ends 54a and 56a are not pinned or riveted into sleeves
46a and 48a but are free to slide thereon. However,
khe wheel suspending and shock absorbing properties
of assembly lOa are substantially the same as those
already described for assembly 10 and the two assemblies
function similarly. Both are very inexpensive to
make and maintain, durable and efficient and are
adaptable to a wide variety of applications. Both
can be constructed of similar materials.
Various changes, modifications, alterations and
additions can be made in the assembly of the present
invention, its components and their parameters. All
such modifications, additions, alterations and changes
as are within the scope of the appended claims form
part of the present application.
