Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates ~o improvements in rims for use
on off road vehicles such as vehicles utilized to haul large
quantities of earth to construc~ion sites or ore at mining
operations. These vehicles typically haul many tons of material
at one time and usually over rough surfaces so that, therefore,
all parts of the vehicle are sub~ected ko great stress and strain
and this is particularly trua with respect to the rims on which
the vehicle tires are mounted. Since the rims and tires are very
large they can be mounted in the same way that on-road vehicles
such as cars and truck tires where the tires are stretched over
the rims, but attempts by otheræ to do this have proven
unsuccessful. Ins~ead, for large off-road vehicles the rims must
be constructed in a way so that the tires are mounted ~lithout
stretching the bead.
Others have devised rim arrangements for off-road
vehicles such as revealed in the following United States Patents:
3,129,034; 2,660,476; 3,468,584; 2,270,918; Re. 27,22~; 2,521,260;
4,021,077; 3,421,797; and 2,261,637.
Summary of the Invention
The present invention is directed towards improvement in
the state of the art as represented by the present commercially
used off-road vehicle rims as well as those exemplified in the
prior art s~ch as in the above-referenced patents. The rim of the
present invention is formed of a tubular ri-m base having a firs~
and second end. A flrst and second circular bead flange is
employed. One of the bead flanges is a permanently affixed part
of the rim base and the other bead flange is slidably positioned
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65224-367
on the outer circumferential surface of the base. The firs~ bead
flange is either integrall~ formed wi~h the rim base or i5
slidably positioned on the first end of the rim base and welded in
posi~ion.
More specifically, the invention provides a rirn for a
wheel for use on a heavy, off-road vehicle, comprising: a tubular
rim base member having a firs~ and a second end and havin~ an
inner and outer circumferential surface, the rim base member
having a circumferential groove in the outer c~lindrical surface
adjacent the second end thereof; first and second substantiall~
identical circular bead flanges, each having an inner and an outer
end and an inside and an outside surface, each having an internal
diameter permitting sliding reception onto said rim base member,
each having a circumferential recess in said inside surface at
said outer end, the first bead flange being received on and welded
to said rim base member, the weld being formed in said first bead
flange circumferential recess and at said rim base member first
end; and a split lock ring removably receivable within said rim
base member circumferential groove, said second bead flange being
received on said rim base member at said second end and said
recess in the said inside surface at said outer end thereof, said
second bea~ flange when urged towards said rim base second end
engages the lock r~ng to prevent the lock ring from escaping out
of said semi-circular groove, and the lock ring prevents said
second bead flange from passing off the second end of said rim
base member, said first and second bead flanges being configured
to receive the opposed beads of a tire mounted thereon, wherein
55224-367
said rim base member has an external circumferential recess in
said outer circumferential suxface at said inner end, which recess
is opposed to said circumferential recess in said first bead
flange, said weld being formed in said opposed recesses in said
rim base member and said first bead flange.
In a preferred embodiment both bead flanges are
separately formed and slide on the rim ba.se and the bead flanges
are preferably substantially identically configured. Each slide-
on bead flange has in cross-sectional configuration, a generally
flat, horizontal base portion and an integral upstanding radially
extending portion.
The use of a circular lock ring in a semi-circular
recess greatly improves the performance over existing rims in that
the stress load of the lock ring against the rim is more equally
distrlbuted to thereby reduce the chance of fatigue failure of the
rim or its parts.
By the employment of identical, or substantially
identical first and second bead flanges the economy of
construction of the rim is greatly improved and the circular lock
ring lends itself to economy of construction.
A better understanding of the invention will be had by
reference to the following description and claims, taken in
conjunction with the attached drawing.
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Description of the Druwin~
Figure I is a cross-sectional view of a rim
according to this invention, the rim being intended for
use on large off-road vehicles.
Figure 2 is a cross-sectional view as in Figure
1 but showing a more preferred embodiment of the invention
wherein two substantially identical bead flsnges are
employed.
Figure 3 is a cross-sectional view as in Figures
I and 2 but showing an alternate embodiment of the
invention wherein the first bead flange is retained in
position by an integral, increased diameter,
circumferential seat formed as a part of the rim base
member.
Figure 4 is a fragmentary cross-sectional view
of the rim base adjacent the second end and showing the
second bead flange in cross-section and showing an
alternate location of un O-ring seal.
Figure 5 is a fragmentary cross-sectional view
of the embodiment of Figure 4 when the bead flange and
lock ring are in operating positions.
Figure 6 is a fragmentary cross-sectional view
of the first end portion of the rim base member and the
first bead flange and showing an alternate location of the
O-ring gasket.
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Description of Preferred Embodiment
Referring to the drawings, Figure I shows one
embodiment of the invention and is a fragmentary cross-
sectional view of a rim for use on off-road vehicles. The
rim is formed of a rim base member generally indicated by
the numersl 10. In the illustrated arrangement the rim
base member is fabricated of three portions. The first
portion indicated by the numeral 12 includes an integral,
circumferential, bead flange portion 14 providing a
contoured inner tire engaging surface 16. A second, or
intermediate rim base portion 18 is welded at 20 and 22 to
the first rim buse portion 12. The third or outer rim
base portion 24 is welded at 26 and 28 to the intermediate
rim base portion 18. Thus, the three portions 12, 18, and
24 are welded together to form an integrul rim base member
10 having an inner end 30 and an outer end 32 and having
an outer surface 34 and an inner surface 36.
Slidably positioned on the rim base member 10 is
a second bead flange portion generally indicated by the
numeral 38 The second bead flange 38 includes a first
base portion 40 which is generally straight and horizontal
in cross-section, and an integral, radially extending
portion 42 which provides an inner tire engaging contour
surface 44 of substantially the identical shape of the
inner contour surface 16 of bead flange portion 14.
Formed in the rim base member outer surface 34
adjacent the outer end 32 is a semi-circular groove 46.
The second bead flange 38 includes a circumferential
recess 48 which is at the flange outer end 50 and inner
surface 52.
Spaced from the semi-circular groove 46 is a
srnaller depth circumferential groove 54 which receives an
O-ring 56. The function of O-ring 56 is to retain air
within a tire plflced on the rim.
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Received in the semi-circular recess 46 is a
split, circular, lock ring 58 of circular cross-sectional
configuration.
When a tire is to be mounted on the rim 10 the
second bead flange 38 is removed. The tire is placed on
the rim from the outer end 32. The tire is collapsed,
that is, does not have any internal air pressure and,
therefore, the sidewalls are flexible. The second bead
fiange 3B is then slidably positioned on the rim from end
32 and inwardly displaced past the groove 54. O-ring 56
is placed in the groove and the lock ring 58 is placed in
the semi~circular groove 46. Air can then be applied to
the tire which, in Figure 1, is indicated in dotted
outline and ideneified by numeral 60. As the air pressure
expands the sidewalls of the tire outwardly, the second
bead flange 38 moves outwardly, sealing against the O-ring
56. The recess 48 engages the lock ring 58 to trap it
into position. In turn, the trapped lock ring prevents
the further outward sliding displacement of the second
flange 38, thereby retaining tire 60 in position on the
rim.
The cross-sectional configuration of the lock
ring 58 is extremely importunt. Due to the extremely
heavy load and rough terrain over which heavy off-road
vehicles subject a rim, great stresses are applied to all
portions of the rim. This is particularly true of the
lock ring holding the rim in position. With present
Commercial devices, such as exemplified in the issued U.
S. patents previously referenced, lock rings are of
irregular cross-sectional configuration sitting in
irregular shaped grooves. These irregular shapes cause
areas of stress concentration. The present invention
overcomes this problem by providing a circular cross-
sectioned lock ring sitting in a semi-circular cross-
sectioned groove so that the stresses are applied over a
wide area free of points of stress concentration. Tn
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addition, the circular cross-sectioned lock ring is much
more economical to manufacture than lock rings with more
complex shapes.
Figure 2 shows an alternate and preferred
embodiment of the invention. In Figure 2 the rim base
member 62 is a generally tubular member formed of a first
tubular portion 64 and a second tubular portion 66, the
portions being welded together at 68 and 70. The rim base
has an inner end 72 and an outer end 74 and a
circumferential exterior surface 76. The rim of Figure 2
employs two bead flange members the first being generally
indicated by the numeral 78 and the second by the numeral
80. The members 78 and 80 are substantially identical and
preferably are formed from identically made base members
which can be machine formed or cast. It can be easily
appreciated that by manufacturing a rim wherein the bead
flanges 78 and 80 are finished from the same basic
structure the overall cost of manufacture is reduced.
Each of the bead flanges 78 and 80 includes a first
generally straight, horizontal base portion 78A and 80A
respectively, and an integral, generally radially
extending portion 78B and 80B respectively. These
radially extending portions provide tire engaging contour
surfaces 82 and 84.
The inner circumferential surfaces 86 and 88 of
the bead flanges are of an internal diameter to be
slidably received on the exterior surface 76 of the rim
base member.
Each of the bead flanges has a circumferential
recess 90 and 92 respectively, formed at the juncture of
the bottom surfaces 86 and 88 respectively, and the outer
ends 94 and 96 respectively. ~-
ln manufacturing a rim of Figure 2 the first
bead member 78 is slid into position on the rim base 62
and a weld 98 is applied between the recess 90 and the
inner end 72 of the first rim base tubular portion 64.
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After weld 98 is applied the first bead flange 78 remains
permanently affixed to the rim.
The second bead flange 80 functions in the same
manner as described with reference to Figure 1. When a
tire is to be installed it is put on the rim uninflated
and is pushed inwardly to engage the first bead flange
78. The second bead flange 80 is slid into position on
the rim base and pushed inwardly far enough to permit the
placement of an O-ring 100 which fits in groove 102. Next
the split circular cross-sectional lock-ring 104 is
positioned in the semi-circular groove 106. Air pressure
can then be applied to the interior of tire 108 expanding
the sidewall outwardly against the second bead flange 80,
sliding the bead flange towards the rim base outer end 74
trapping the lock ring 104 in place.
The embodiment of Figure 2 has all of the
advantages of the circular cross-sectioned lock ring of
Figure 1, plus the additional advantages of simplicity of
construction. As previously indicated, the use of bead
flanges having substantially identical configuration has
obvious economic advantages. The bead flanges have been
described as being of substantially identical cross-
sectional configuration since they can vary somewhat. For
instance, both bead flanges could be manufactured from the
identical castings or forgings with slight changes made
during final machining of the inner and outer flanges.
For instance, the configuration of the circumferential
recesses 90 and 92 may vary. On the other hand, the rim
can be manufactured wherein the first and second bead
flanges are identical, such as shown in the Figure 2.
In the arrangernent of both of Figures I and 2
the radial flange portions of the bead flanges can be
configured so as to be slightly flexible. This is
achieved by carefully designing the configuration of the
radial portions which provide the contoured surfaces 16
and 44 of Figure I and 82 and 84 of Figure 2. By varying
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the thickness of the flange portions 14 and 42 of Figure I
and 78B and 80B of Figure 2, a degree of flexibility can
be achieved so that slight deflections of the radial
portions of the bead flanges can take place so this
flexibility is optimized for the tire being used, (i.e.,
bias or radial). Flexibility must be controlled, however,
since the bead flange must be sufficiently stiff to
minimize chafing between the tire and the rim.
Note that in ~igures I and 2 all of the welds
are in areas which are subject to the pressure of the air
within tire 108. This means that if a weld breaks or
start to break, air will leak frorn the tire giving an
indication that a failure of the rim muy be imninent.
Referring now to Figure 3 an alternate
embodiment of Figure 2 is shown in which the rim base
member 62A is formed of a unitary structure and has, at
the first end 72 thereof, an enlarged external diameter
circumferential seat portion 110. The seat portion 110
has an edge 112 which is configured to matingly receive
the recess 90 in the first bead flange member 78.
The rim base member 62A has, on the exterior
surface 76, adjacent the bead portion 110, a
circumferential srnall diameter recess 114 which receives
an O-ring gasket 116.
The embodiment of Figure 3 permits the use of
substantially identical flanges 78 and 80 as in Figure 2
but in the arrangement wherein the first flange 78 is
removably received on the rim base member. Since the
first bead flange 78 must be slid into a position over the
first end 74 of the rim base member, the maximum diameter
of the exterior surface 76 of the rim base member must be
maintained substantially uniform, that is, it can not have
any portions between the second end 74 and the seat
portion 110 which is greater in exterior diameter than the
interior diameters of the bead flange 78. The increased
external diameter which provides the circumferential seat
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portion 110 services to strengthen the rim in the same way
that the increased thickness of the rim in the portion
adjacent the first end 74 strengthens the rim.
Figures 4 and 5 show an alternate locution for
the O-ring gasket 100 as previously described with
reference to Figure 2. A small diameter circumferential
groove 118 is provided in the rim base member continguous
to the semi-circular groove 106. As shown in Figure 5,
when the second flange 80 and the lock-ring 104 are in
position on the rim base member, the O-ring 100 is in
sealed engagement with these three members. This means
that during the mounting of a tire, if the lock ring 104
is not in proper position and fully recessed within the
semicircular groove 106 so as to be sealably engaged by
the O-ring 100 around its full circumference, then the
tire will not hold air. This prevents the tire from being
fully inflated if the lock ring is not in its correct
position accomplishing an important safety advantage.
Figure 6 shows a similar arrangement with
respect to the first bead flange 78. In this embodiment a
small diameter groove 120 is forrned in the interior
surface of the first bead flange 78 and receives the O-
ring gasket 116. This gasket seals against the mating
edge 112 of the integral seat portion 110 when the first
bead flange is in proper position. In this way the tire
can not hold air if the first bead flange is not properly
seated with respect to the seat portion 110 of the flange
base member.
It can be seen that in the embodiment of Figures
3 wherein the first and second bead flanges 78 and 80 are
~oth removably supported with respect to the rim buse
member that by using the air seal arrangements of Figures
4 5 and 6 a proper installation indication is achieved
when the tire is positioned on the rim and retains air.
The failure of the tire to properly inflate provides an
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indicution of improper positioning of the elements making
up the rim.
While the invention has been described with a
certain degree of particularity it is manifest that many
cllunges may be made in the details of construction and the
arrangement of components without departing from the
spirit and scope of this disclosure. It is understood
that the invention is not limited to the embodiments set
forth herein for purposes of exemplification, but is to be
limited only by the scope of the attached claim or claims,
including the full range of equivalency to which each
element thereof is entitled.
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