U.S. patent application number 16/249984 was filed with the patent office on 2019-07-04 for irrigation tire.
The applicant listed for this patent is Bridgestone Americas Tire Operations, LLC. Invention is credited to Keith A. Dumigan, Andrew T. Miklic, Jeffrey D. Parker, John J. Regallis, Nobuo Shimizu, Bill J. Wallet.
Application Number | 20190202243 16/249984 |
Document ID | / |
Family ID | 40506841 |
Filed Date | 2019-07-04 |
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United States Patent
Application |
20190202243 |
Kind Code |
A1 |
Wallet; Bill J. ; et
al. |
July 4, 2019 |
Irrigation Tire
Abstract
A non directional pneumatic tire is provided for an agricultural
irrigation system. The tire includes first and second side walls
and a radially outer wall defining an internal inflation chamber. A
non directional tread pattern is defined on the tire and includes a
plurality of longitudinal protrusions positioned substantially
parallel to a rotational axis of the tire. The longitudinal
protrusions are arranged in first and second rows extending from
the first and second side walls toward and across the equatorial
plane of the tire. The longitudinal protrusions of the first and
second rows circumferentially alternate with each other and there
is a circumferential spacing between adjacent longitudinal
protrusions at the equatorial plane so that no portion of one
longitudinal protrusion circumferentially coincides with or
overlaps another.
Inventors: |
Wallet; Bill J.;
(Marshallville, OH) ; Regallis; John J.; (Akron,
OH) ; Parker; Jeffrey D.; (Copley, OH) ;
Shimizu; Nobuo; (Tokyo, JP) ; Miklic; Andrew T.;
(Akron, OH) ; Dumigan; Keith A.; (Akron,
OH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Bridgestone Americas Tire Operations, LLC |
Nashville |
TN |
US |
|
|
Family ID: |
40506841 |
Appl. No.: |
16/249984 |
Filed: |
January 17, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14822954 |
Aug 11, 2015 |
10272724 |
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16249984 |
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11865085 |
Oct 1, 2007 |
9108469 |
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14822954 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60C 13/00 20130101;
B60C 11/033 20130101; B60C 11/032 20130101; B60C 11/0311 20130101;
B60C 11/0316 20130101; B60C 11/0332 20130101; B60C 3/04 20130101;
B60C 11/0304 20130101; B60C 2011/0388 20130101; B60C 2200/08
20130101; B60C 1/00 20130101; B60C 11/1307 20130101 |
International
Class: |
B60C 11/03 20060101
B60C011/03 |
Claims
1. A non-directional pneumatic tire for supporting an agricultural
irrigation system, comprising: first and second sidewalls and a
radially outer wall defining an internal inflation chamber; a
non-directional tread pattern defined on the tire and including a
plurality of longitudinal protrusions positioned substantially
parallel to a rotational axis of the tire; and the longitudinal
protrusions being arranged in a first row extending from the first
sidewall toward and across an equatorial plane of the tire and a
second row extending from the second sidewall toward and across the
equatorial plane of the tire, the longitudinal protrusions of the
first and second rows circumferentially alternating with each other
and there being a circumferential spacing between adjacent
longitudinal protrusions at the equatorial plane so that no portion
of one longitudinal protrusion circumferentially coincides with
another; wherein each longitudinal protrusion includes a contact
surface that increases in circumferential width from its respective
sidewall toward the equatorial plane of the tire and tapers to an
axially inner end; and wherein the contact surface of each
longitudinal protrusion has substantially straight edges between
its respective sidewall and the equatorial plane of the tire.
2. The tire of claim 1, wherein: the axially inner end of each
longitudinal protrusion is rounded.
3. The tire of claim 1, wherein: the contact surface of each
longitudinal protrusion continuously increases in circumferential
width all the way from its respective sidewall to the equatorial
plane of the tire.
4. The tire of claim 3, wherein: the taper to the axially inner end
of each longitudinal protrusion begins substantially at the
equatorial plane.
5. (canceled)
6. The tire of claim 1, wherein: the contact surface of each
longitudinal protrusion circumferentially eccentrically tapers to
the axially inner end.
7. The tire of claim 1, wherein: the contact surface of each
longitudinal protrusion circumferentially symmetrically tapers to
the axially inner end.
8. The tire of claim 1, wherein: the contact surface of each
longitudinal protrusion continuously increases in circumferential
width past the equatorial plane of the tire.
9. The tire of claim 1, wherein: the contact surface of each
longitudinal protrusion continuously increases in circumferential
width to a location short of the equatorial plane of the tire, and
then decreases in circumferential width to and past the equatorial
plane of the tire.
10. The tire of claim 1, wherein the tread pattern has a relatively
low rubber to void ratio over a tire width of less than about
20%.
11. The tire of claim 1, wherein the tread pattern has a rubber to
void ratio over a tire width in the range of from about 16% to
about 20%.
12. The tire of claim 1, wherein an aspect ratio of the tire
defined as tire section height divided by tire section width is no
greater than about 90%, thereby providing a relatively wide
tire.
13. The tire of claim 1, having a tire section width of at least 10
inches.
14. The tire of claim 13, having an outside diameter of at least 40
inches.
15. The tire of claim 1, having a tread pitch in the range of 10 to
25, the tread pitch being defined as the number of longitudinal
protrusions in one of said first and second rows.
16. The tire of claim 15, wherein the tread pitch is in the range
of 15 to 21.
17. The tire of claim 15, wherein an outside diameter of the tire
is at least about 40 inches.
18. The tire of claim 1, wherein: the radially outer wall has an
inner tread defined thereon between the longitudinal protrusions;
and each longitudinal protrusion includes a protrusion side, each
protrusion side including a first taper surface extending from the
contact surface and a second taper surface extending from the first
taper surface to the inner tread.
19. The tire of claim 1, wherein the tire comprises rubber and an
anti-weathering agent, the anti-weathering agent comprising at
least 8 parts per hundred parts of the rubber.
20. The tire of claim 19, wherein the anti-weathering agent
comprises 8-18 parts per hundred parts of the rubber.
21. The tire of claim 19, wherein the anti-weathering agent is
selected from the group consisting of wax, an anti oxidant, resin,
an anti ozonant and combinations thereof.
22. The tire of claim 1, wherein: the tread pattern further
includes a circumferential protrusion spanning the equatorial
plane, each of the longitudinal protrusions having a terminal end
portion overlying the circumferential protrusion.
23. The tire of claim 22, wherein: the terminal end portion of each
longitudinal protrusion is enlarged circumferentially.
24. A non-directional pneumatic tire for supporting an agricultural
irrigation system, comprising: first and second sidewalls and a
radially outer wall defining an internal inflation chamber; and a
non-directional tread pattern defined on the tire and including two
rows of alternating circumferentially spaced circumferentially
eccentric lugs, each lug including a contact surface that increases
in circumferential width from its respective sidewall toward the
equatorial plane of the tire and then tapers to a rounded end.
25. The tire of claim 24, wherein: the contact surface of each
longitudinal protrusion continuously increases in circumferential
width all the way from its respective sidewall to the equatorial
plane of the tire.
26. The tire of claim 25, wherein: the taper to the rounded end of
each longitudinal protrusion begins substantially at the equatorial
plane.
27. The tire of claim 24, wherein: the contact surface of each
longitudinal protrusion has substantially straight edges between
its respective sidewall and the equatorial plane of the tire.
28. The tire of claim 24, wherein: the contact surface of each
longitudinal protrusion circumferentially eccentrically tapers to
the rounded end.
Description
BACKGROUND OF THE INVENTION
Field of the Invention
[0001] The present invention relates generally to tires and to
non-directional tires used in agricultural settings. More
specifically, but without limitation, the present invention relates
to non-directional pneumatic tires designed to support agricultural
irrigation systems.
Technical Background
[0002] The development of specific tires to fill a specific need
for various wheeled devices is well known in the art. Most of this
focus has been directed at the development of tires for vehicles,
such as automobiles, wherein those tires are designed to spend a
great majority, if not all, of their useful life on paved
surfaces.
[0003] Another area of conventional tire development is the
"off-road" tire that is used on various "off-road" vehicles such as
trucks, SUV's, and similar vehicles, where those "off-road"
vehicles spend most of their time on paved surfaces and a smaller
portion of their time on non-paved surfaces. However, most of these
"off-road" tires have a specific direction of rotation designed
into the "off-road" tire. This is due to the fact that these
"off-road" vehicles have a preferred forward direction of movement,
which corresponds into a specific preferred direction of rotation
designed directly into the prior art "off-road" tires. This
preferred direction of rotation for the tire leads to tire designs
having characteristics, such as tread pattern, that cause the tire
to specifically perform better when the tire is rotated in a
specific direction. For example, the "off-road" tires perform
significantly better when rotated in a forward direction with
respect to the vehicle versus a backwards direction with respect to
the vehicle.
[0004] These prior art tires have several drawbacks for vehicles
that spend any significant amount of time moving in both forward
and backward directions. For example, these prior art tires result
in an uncomfortable and turbulent movement to the vehicle supported
by those prior art tires when moved in a reverse direction. A
majority of this turbulence is due to the specific tread pattern on
these prior art tires and the orientation of the various elements,
commonly referred to as lugs, on the tread pattern.
[0005] Additionally, the prior art single directional tires also
require different mounting techniques for each side of the vehicle.
These multiple mounting techniques are normally necessitated by the
fact that the tread of these single directional tires is designed
to operate in a specific orientation with respect to the direction
of travel of the vehicle. As such, these single directional tires
must be properly oriented with respect to the wheel on which these
tires are mounted and more specifically to the side of the wheel
that is to be mounted on the vehicle.
[0006] The field of agriculture is one area in which the apparatus,
or vehicle, supported by wheels and tires can benefit from tires
that are designed to traverse the ground with substantial
similarity in both forward and backward directions (i.e.,
non-directional tires). Additionally, tires for agricultural
apparatus normally are enhanced by a tread pattern that is
specifically designed for use on non paved surfaces. A substantial
portion of agricultural devices, such as tractors, trailers, crop
planting devices, crop harvesting devices, and the like, are used
in locations, such as agricultural fields, when it is undesirable
for the agricultural device to substantially alter the ground upon
which they move.
[0007] One type of agricultural apparatus in particular that is
normally positioned in an agricultural field, can benefit from
non-directional tires, and preferably does not substantially damage
or alter the ground upon which it moves is an irrigation system.
Tires possessing non-directional capability can substantially
improve the operation of the agricultural apparatus in the event
the normal direction of travel is reversed. More importantly, tires
so designed, can shorten the tire and wheel installation time
required for the agricultural apparatus. This is due to the fact
that a non-directional tire can reduce the need for multiple
mounting techniques between the wheel and the apparatus. As such, a
single mounting can be used for all of the wheel mounts regardless
of their orientation with respect to the direction of travel of the
apparatus. Additionally, the installation person would not be
required to specifically align a non-directional tire with respect
to the wheel used on an irrigation system, as would be required for
a single directional tire.
[0008] As such, irrigation tires positioned on the irrigation
system should be designed to move in either direction with similar
ease, possess the proper dimensions to adequately support the
weight of the irrigation system, including weight of the water
supported by the irrigation system, and be designed to be light
enough and have the proper tread pattern to refrain from, or
minimally alter, the ground over which the irrigation system
travels.
[0009] Most conventional irrigation tires, and most conventional
agricultural tires, have a tread pattern that is specifically
designed for a single preferred direction of rotation. Most of
these conventional tires have lugs that angle towards the center
part of the tire and are not parallel with the axis of the tire.
Additionally, a majority of the irrigation tires are comprised of
solid rubber that is molded to the wheel of the irrigation system.
These types of tires can be very heavy and damage the ground upon
which the irrigation system traverses. Also, these irrigation tires
do not contemplate altering the composite of the tires to
specifically protect the tires against the weathering elements to
which the tires are exposed during their useful life.
[0010] What is needed then is an irrigation tire that is designed
for movement in multiple rotational directions, is comprised of
materials designed to have a minimal impact on the ground to which
the irrigation system traverses, is comprised of materials to
lengthen the useful life of the tire and withstand weathering by
the elements, and is designed to facilitate improved traction with
the ground upon which it travels. This needed tire is lacking in
the art.
BRIEF SUMMARY OF THE INVENTION
[0011] Included herein is a non-directional pneumatic tire having a
diameter and a width sufficient to support an agricultural
irrigation system. The tire is preferably used in conjunction with
a wheel to support the agricultural irrigation system. The tire can
further include a top layer and side walls, wherein the top layer
and side walls define an interior chamber when positioned on the
wheel. The interior chamber can be shaped to hold a gas, such as
air, to facilitate the support of irrigation system.
[0012] The tire can include an axis and a tread pattern positioned
on the tire. The tread pattern includes a plurality of longitudinal
protrusions positioned substantially parallel with the axis. The
longitudinal protrusions preferably provide substantially the same
coefficient of friction between the tire and the surface upon which
the tire rotates when the tire is rotated in opposite directions
with respect to the axis. The tread pattern can further include a
circumferential protrusion positioned approximately at the mid
point of the width of the tire.
[0013] Each longitudinal protrusion can further include a terminal
end that extends toward the mid-point of the width of the tire. The
circumferential protrusion can space the terminal end of each
longitudinal protrusion away from the axis of the tire.
Additionally, the terminal end of each longitudinal protrusion can
extend past the terminal end of adjacent longitudinal protrusions.
The longitudinal protrusions have a circumferential spacing between
adjacent longitudinal protrusions at the equatorial plane so that
no portion of one longitudinal protrusion circumferentially
coincides with another.
[0014] The tire can be comprised of rubber, and can further include
an anti-weathering agent. The anti-weathering agent can comprise at
least 8 parts per 100 parts of the rubber of the total composition
of the tire. Preferably the anti weathering agent can comprise
between 8-18 parts per 100 parts of rubber. The anti weathering
agent can comprise wax, an anti oxidant, resin, an anti ozonant or
combinations thereof.
[0015] Also included is a non directional pneumatic tire used to
support an agricultural irrigation system. The tire includes a
raised tread pattern having a substantially centrally positioned
circumferential lug and longitudinal lugs circumferentially
positioned parallel to the axis of the tire. The longitudinal lugs
preferably extend from the side walls of the tire towards the
circumferential lug and include a terminal end positioned on the
circumferential lug. The circumferential lug and terminal ends of
the longitudinal lugs preferably provide a substantially uniform
resistance between the tire and the surface upon which the tire
rolls when the tire is rotated in opposite directions.
[0016] The circumferential lug and longitudinal lugs can also be
positioned to increase the crown strength of the tire and to
increase the traction performance and cleaning ability of tire.
Additionally, the tread design can be designed such that there is a
reduced contact pressure between the tire and the surface upon
which it traverses.
[0017] The tire can include an anti weathering agent to increase
the ozone resistance of the tire. In addition the tire can include
a tread durometer of less than 55 shore A hardness.
BRIEF DESCRIPTIONS OF THE SEVERAL VIEWS OF THE DRAWINGS
[0018] FIG. 1 is a perspective view of a first embodiment of a tire
made in accordance with the current disclosure.
[0019] FIG. 2 is a perspective view of a second embodiment of a
tire made in accordance with the current disclosure.
[0020] FIG. 3 is a perspective view of a third embodiment of a tire
made in accordance with the current disclosure.
[0021] FIG. 4 is a perspective view of a fourth embodiment of a
tire made in accordance with the current disclosure.
[0022] FIG. 5 is a partial plan view of the tread of the tire shown
in FIG. 2.
[0023] FIG. 6 is a cross sectional view of a tire made in
accordance with the current disclosure showing the internal cavity
formed between the side walls, top layer, and wheel.
[0024] FIG. 7 is an elevation view of an example of an agricultural
irrigation system supported by the current invention.
[0025] FIG. 8 is a partial plan view, similar to FIG. 5, of the
tread of a tire made in accordance with the current disclosure.
[0026] FIG. 9 is a partial plan view, similar to FIGS. 5 and 8, of
the tread of a tire made in accordance with the current
disclosure.
[0027] FIG. 10 is a partial cross-sectional view taken along lines
10-10 of FIG. 8 or 9.
[0028] FIG. 11 is a partial cross-sectional view taken along lines
11-11 of FIG. 8 or 9.
[0029] FIG. 12 is a partial cross-sectional view taken along lines
12-12 of FIG. 8 or 9.
[0030] FIG. 13 is a partial cross-sectional view taken along lines
13-13 of FIG. 8 or 9.
[0031] FIG. 14 is a partial cross-sectional view taken along lines
14-14 of FIG. 8 or 9.
[0032] FIG. 15 is a view similar to FIG. 2 showing another
alternative tread design having a different shape enlarged head on
the lugs.
[0033] FIG. 16 is another view similar to FIG. 2 showing still
another alternative tread design having a different shape enlarged
head on the lugs.
DETAILED DESCRIPTION OF THE INVENTION
[0034] Referring generally to FIGS. 1-16, a tire is shown and
generally designated by the numeral 10. The tire 10 is preferably
used to support an agricultural irrigation system 12 as the
agricultural irrigation system 12 traverses across a surface 14.
The surface 14 is preferably a field in need of hydration. Tire 10
is a non-directional pneumatic tire having a diameter 16 and a
width 18 sufficient to support the agricultural irrigation system
12. The tire 10 is used in connection with a wheel 20 to support
the agricultural system 12 on the surface 14.
[0035] Preferably the tire 10 includes a top layer or top wall 22
and side walls 24 and 26 that define an internal chamber 28 when
the tire 10 is positioned on the wheel 20. The internal chamber 28
can be shaped to hold a gas which can provide the pneumatic
properties for the tire 10.
[0036] The tire 10 can include a rotational axis 30 and tread
pattern 32 positioned on the tire 10. The tread pattern 32
preferably includes a plurality of longitudinal protrusions 34,
which can be described as longitudinal lugs 34, positioned
substantially parallel to the axis 30. Preferably the longitudinal
protrusions 34 are positioned to provide substantially the same
coefficient of friction between the tire 10 and the surface 14 when
the tire 10 is rotated in opposite directions relative to the axis
30. This can also be described as the tire 10 being a
non-directional tire.
[0037] Preferably, the tread pattern 32 includes a circumferential
protrusion 36, which can also be described as a circumferential lug
36, positioned approximately at the mid-point or equatorial plane
38 of the width 18 of the tire 10. The circumferential protrusion
36 can space the longitudinal protrusions 34 away from the axis 30.
More specifically, the longitudinal protrusions 34 can include a
terminal end 40 which can be spaced by the circumferential
protrusion 36 away from the axis 30. The terminal end 40 of each
longitudinal protrusion 34 extends towards and across the mid point
or equatorial plane 38 of the tire 10. This can best be seen in
FIGS. 1-5.
[0038] The longitudinal protrusions 34 are arranged in first and
second rows extending from the side walls 24 and 26 towards and
across the mid point or equatorial plane 38 and terminating within
the width of the circumferential protrusion 36. Additionally, the
terminal end 40 of each longitudinal protrusion 34 can extend past
the terminal end 40 of adjacent longitudinal protrusions 34 of the
opposing row.
[0039] As is apparent for example in FIG. 5, the longitudinal
protrusions or lugs 34 of the first and second rows
circumferentially alternate with each other. There is a
circumferential spacing 37 such as shown in FIG. 5 between adjacent
longitudinal protrusions of opposing rows at the equatorial plane
38 of the width of the tire. Thus due to this circumferential
spacing 37 no portion of one longitudinal protrusion or lug 34
circumferentially coincides with or overlaps another adjacent
longitudinal protrusion or lug 34.
[0040] FIG. 5 shows a plan view of a tire with a tread pattern made
in accordance with the current disclosure. The dotted lines in FIG.
5 show the approximate location of the connection line in the tire
10 between the top layer 20 and sidewalls 24 and 26.
[0041] FIGS. 8 and 9 generally show a plan view of a tire with a
tread pattern made in accordance with the current disclosure. FIG.
8 shows an example of the spacing of a tread pattern comprising 15
longitudinal protrusions per side of the tire (i.e. a pitch of 15)
while FIG. 9 shows an example of the spacing of a tread pattern
comprising 18 longitudinal protrusions per side of the tire (i.e. a
pitch of 18).
[0042] FIGS. 10-14 generally show partial cross-sectional views
taken along various lines of FIG. 8 or 9. FIGS. 10-12 show examples
of the protrusion sides 50 having multiple taper sections extending
between the outer and inner contact surfaces as previously
described. The multiple slopes of these surfaces facilitate
traction, increase crown strength, increase tire durability, and
enhance cleaning ability for the tire 10.
[0043] As seen in FIGS. 3-4, the tread pattern 32 can include
additional features to facilitate the performance of the tire. For
example, the longitudinal lugs 34 can include a recessed area 56
used to facilitate the traction of the tire 10. Additionally,
intermediary lugs 58 can be positioned between the longitudinal
lugs 34. These intermediary lugs 58 can take a variety of shapes
including a rib pattern as seen in FIG. 3, a wavy pattern as seen
in FIG. 4, or other similar patterns used to increase the
performance of the tire 10.
[0044] The protrusions 34 can also include tread bars 60 positioned
substantially along the protrusion axis 44 of the longitudinal
protrusions 34.
Shapes of Longitudinal Lugs
[0045] The terminal end 40 of each longitudinal protrusion 34 can
comprise various shapes. For example as shown in FIG. 1, an end can
be substantially round and be described as a rounded end 42. This
rounded end 42 can be positioned substantially along a protrusion
axis 44 (see FIG. 5) for each longitudinal protrusion 34. First and
second bulges 46 and 48, which can also be described as
circumferential enlargements 46 and 48, can extend from the
protrusion axis 44, as best seen in FIGS. 2-5, 8 and 9. These
bulges 46 and 48 can narrow to the rounded end 42. Alternately, the
terminal end 40 of the longitudinal protrusions 34 can be described
as being substantially spade shaped as exemplified in FIGS.
2-5.
[0046] FIG. 15 shows still another alternative shape of enlarged
head which is similar to that of FIG. 5 but does not have the
distinct circumferentially extending bulges 46 and 48. Also in the
design of FIG. 15 the longitudinal lugs 34 extend longitudinally to
the edge of the circumferential lug 36.
[0047] In FIG. 16 still another shape of the longitudinal lugs is
shown. In FIG. 16, the lugs 34 have asymmetrically shaped enlarged
heads with the heads of the first row facing circumferentially in
opposite directions from the heads of the second row.
[0048] These various shapes of the longitudinal protrusions 34
alone, and in combination with, the circumferential protrusion 36
facilitate increased traction performance of the tire 10.
Additionally, these protrusions 34 and 36 can enhance the cleaning
ability of the tire and facilitate the contact of the tire 10 with
the surface 14. Additionally, the tread design, in combination with
the protrusions 34 and 36, facilitate and increases crown strength
in the tire 10.
Representative Dimensions
[0049] Representative dimensions for three proposed sizes of the
tire 10 utilizing the design shown in FIGS. 2, 5, 8 and 9 are set
forth in the following Table I. All dimensions are in inches.
TABLE-US-00001 TABLE I 380/85D24 290/85D38 290/85D24 Champion
Champion Champion Hydro ND Hydro ND Hydro ND Diameter 49.4 57.4
43.5 Section Height 12.7 9.7 9.7 Section Width 15.0 11.4 11.4 Lug
Height 1.48 1.37 1.37 Tie-Bar (Center Lug) Height 0.2 0.2 0.2
Number of Pitches 18 21 16
[0050] Additionally it is noted that there is a relatively wide
spacing between the lugs of each row in the circumferential
direction. This is related to the tread pitch of the tire, the
tread pitch being defined as the number of longitudinal lugs 34 in
either one of the first and second rows. Preferably this tread
pitch is in the range of from 10-25, and more preferably in the
range of from 15-21. These low pitch tires having wide spaces
therebetween provide increased cleaning effectiveness for use in
very muddy environments encountered with irrigation tires. This is
contrasted to designs having much higher pitches which might be
utilized for example to provide more contact area for a tire
operating under more traditional conditions.
[0051] Also, because of their use as irrigation tires, the tires of
the present invention are preferably relatively large tires having
an outside diameter 16 of at least about 40 inches and a tire
section width 18 of at least about 10 inches.
[0052] The large spacing between adjacent lugs 34 on these
relatively large tires also results in a tread pattern having a
relatively low rubber to void ratio, defined as the area of the
radially outer surfaces of the lugs 34, as compared to the total
area across the tire width 18. For the tires of the present
invention such as represented in FIG. 5 and in Table I, the rubber
to void ratio over the tread width 18 is preferably less than about
20 percent, and more preferably in the range of from about 16
percent to about 20 percent.
[0053] Furthermore, these tire dimensions result in a tire 10
having an aspect ratio defined as the tire section height 17 (see
FIG. 6) divided by the tire section width 18 of no greater than
about 90 percent thereby providing a relatively wide tire. As can
be determined from the data of Table I, the aspect ratio of each of
those three tires is about 85 percent.
The Dual-Tapered Lug Sides
[0054] The longitudinal protrusions 34 can include protrusion sides
50 extending from the contact surface 52 of each protrusion 34 down
to lateral grooves 54, which can be described as inner tread 54.
Additionally each protrusion side 50 can be sloped from the contact
surface 52 down to a lateral groove 54. The slope of each of the
protrusion sides 50 can extend around and include a slope for the
rounded end 42 and bulges 46 and 48 from the contact surface 52 to
lateral grooves 54. This can best be seen in FIGS. 2-5, 8, and 9.
The slope of these surfaces facilitates traction, increase crown
strength, increase tire durability, and impediment cleaning ability
for the tire 10.
[0055] For example, the inner tread 54, which can be described as
an inner contact surface 54, can be defined between the protrusion
sides 50 of adjacent longitudinal protrusions 34. As seen in FIGS.
10-12 the protrusion side 50 of each longitudinal protrusion 34 can
include a first taper 62 extending from the contact surface 52 and
a different sloped second taper surface 64 extending from the first
taper surface 62 to the inner tread 54. A third taper 65 can be
positioned between the second taper surface 64 and the inner tread
54. These multiple (dual, bi-, or otherwise) tapered longitudinal
protrusions 34 facilitate an increased durability in the tire 10
and tread pattern 32 by preventing cracking in the longitudinal
protrusions 34, especially near the inner tread 54. The dual taper
edge also reduces the rubber volume required for the lugs. The dual
slope of the protrusion sides 50 also facilitates improved traction
and cleaning ability for the tire 10 through the movement of loose
sections of the ground surface 14 when the tire traverses the
surface 14.
[0056] Each longitudinal protrusion 34 can be described as being
positioned opposite the location of an inner tread 54 and
circumferentially inside oppositely positioned adjacent
longitudinal protrusions 34. Alternately described, as indicated on
FIG. 5, the first and second bulges 46 and 48 of adjacent
longitudinal protrusions 34 (i.e. first and second longitudinal
protrusions 34A and 34B) can define a chord length 66 between the
adjacent longitudinal protrusions 34A and 34B. A longitudinal
protrusion 34C can be positioned opposite the chord length 66 such
that the width 68 of the oppositely positioned longitudinal
protrusion 34C is less than the chord length 66. This results in
the circumferential spacing 37 between the enlarged heads of
adjacent lugs 34 as shown in FIG. 5.
Anti Weathering Agents
[0057] In a preferred embodiment, the tire 10 comprises rubber and
an anti-weathering agent. The anti-weathering agent preferably
comprises at least 8 parts per 100 parts of rubber in the
composition of the tire 10. In a more preferred embodiment, the
anti-weathering agent comprises between 8-18 parts per 100 parts of
rubber. The anti-weathering agent can comprise elements such as
wax, an anti oxidant, resin, an anti ozonant or combination thereof
to provide ozone resistance and prolong the useful life of the tire
10.
[0058] Thus, although there have been described particular
embodiments of the present invention of a new and useful Irrigation
Tire, it is not intended that such references be construed as
limitations upon the scope of this invention except as set forth in
the following claims.
* * * * *