U.S. patent application number 10/889759 was filed with the patent office on 2004-12-23 for run flat tire support and colorant therefor.
Invention is credited to Bennett, Kimberly F., Christenson, Chris P., Cornell, Martin C., Danielsen, Peder E., Jimenez, Patricio JR., Priester, Ralph D. JR., Tabor, Rick L., Wilkomm, Wayne R., Zawisza, Jeffery D..
Application Number | 20040256043 10/889759 |
Document ID | / |
Family ID | 27398214 |
Filed Date | 2004-12-23 |
United States Patent
Application |
20040256043 |
Kind Code |
A1 |
Tabor, Rick L. ; et
al. |
December 23, 2004 |
Run flat tire support and colorant therefor
Abstract
The present invention provides a unitary run flat tire (RFT)
reinforcement that is formed into a relatively rigid shape. The
reinforcement is insertable into a mold for an RFT support and can
maintain the needed structural rigidity for such insertion.
Further, the invention provides an RFT support that is molded and
includes the RFT reinforcement. The invention also provides a wheel
assembly including a tire, a rim, and an RFT support between the
rim and the tire, where the support includes the RFT reinforcement.
The RFT support can have a colored indicator formed or subsequently
applied thereto to indicate one or more attributes of the
support.
Inventors: |
Tabor, Rick L.; (Gurnee,
IL) ; Wilkomm, Wayne R.; (Eric, CO) ; Jimenez,
Patricio JR.; (Lake Jackson, TX) ; Priester, Ralph D.
JR.; (Lake Jackson, TX) ; Cornell, Martin C.;
(Lake Jackson, TX) ; Bennett, Kimberly F.; (West
Columbia, TX) ; Zawisza, Jeffery D.; (Middland,
MI) ; Christenson, Chris P.; (Lake Jackson, TX)
; Danielsen, Peder E.; (Middland, MI) |
Correspondence
Address: |
THE DOW CHEMICAL COMPANY
INTELLECTUAL PROPERTY SECTION
P. O. BOX 1967
MIDLAND
MI
48641-1967
US
|
Family ID: |
27398214 |
Appl. No.: |
10/889759 |
Filed: |
July 13, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10889759 |
Jul 13, 2004 |
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09948025 |
Sep 6, 2001 |
|
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6779572 |
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60231658 |
Sep 11, 2000 |
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60289958 |
May 10, 2001 |
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60300887 |
Jun 25, 2001 |
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Current U.S.
Class: |
152/520 |
Current CPC
Class: |
B29K 2105/08 20130101;
Y10T 428/24091 20150115; B29C 53/8058 20130101; B29K 2105/04
20130101; B60C 15/0236 20130101; B29K 2075/00 20130101; B29C 48/154
20190201; B29C 48/153 20190201; B29K 2267/00 20130101; B29K 2309/08
20130101; B29C 41/045 20130101; B29K 2025/00 20130101; B29C 39/028
20130101; B29C 48/335 20190201; B29C 48/12 20190201; B29C 35/02
20130101; B29C 2793/009 20130101; B29L 2030/00 20130101; B29C
67/246 20130101; B60C 17/04 20130101; Y10T 152/10738 20150115; B29C
39/10 20130101; Y10T 152/10054 20150115; B29C 53/8075 20130101;
B29C 45/0005 20130101; B29C 53/8066 20130101; B29L 2009/00
20130101; B29K 2063/00 20130101; B29K 2105/0032 20130101; B29K
2995/002 20130101; B29C 53/62 20130101; B29C 53/60 20130101; B29C
48/32 20190201; B29C 48/03 20190201; B60C 17/06 20130101; B60C
2017/068 20130101; B29C 48/08 20190201; B29C 31/04 20130101; Y10T
428/24074 20150115; B29C 48/05 20190201; B29C 53/62 20130101; B29C
53/68 20130101 |
Class at
Publication: |
152/520 |
International
Class: |
B60C 017/02 |
Claims
What is claimed is:
1. A run flat tire (RFT) support, comprising: a) a molded portion
having an outer circumference and an inner circumference and
adapted to mount to a wheel rim to support a deflated tire when the
tire is rolling on a surface, the molded portion further comprising
a colored indicator that indicates at least one attribute of the
RFT support; and b) at least one RFT reinforcement molded into the
molded portion.
2. The RFT support of claim 1, wherein the colored indicator is
adapted to indicate at least one operation attribute of the RFT
support.
3. The RFT support of claim 1, wherein the RFT reinforcement
comprises one effective layer and has a rigidity sufficient to
deform about 20% or less when dropped from about two meters high to
a hard surface when an axis of the reinforcement is substantially
perpendicular to gravity.
4. The RFT support of claim 1, wherein the colored indicator is
applied to the molded portion after molding.
5. The RFT support of claim 1, wherein the colored indicator is
applied by gravure, roll, spin, flow, brush, electrostatic, dip,
spray, immersion, powder coat, coat, paint, or some combination
thereof.
6. The RFT support of claim 1, wherein the colored indicator is
formed in the molded portion by a colorant added in a molding
process of the molded portion.
7. The RFT support of claim 6, wherein the colored indicator can be
added to either an A-side or a B-side or a combination thereof in a
reaction injection molding (RIM) process.
8. The RFT support of claim 6, wherein the colored indicator is
formed in the molding process by a reaction of components.
9. The RFT support of claim 6, wherein the colored indicator is a
dye.
10. The RFT support of claim 1, wherein the colored indicator is
substantially uniform across at least one surface of the molded
portion.
11. The RFT support of claim 1, wherein the colored indicator is
formed from one or more indicia and are perpendicular, parallel, or
at one or more angles to a central axis of the molded portion.
12. The RFT support of claim 1, further comprising a wheel rim
wherein the colored RFT support is adapted to be mounted to the
rim.
13. A run flat tire (RFT) support, comprising a molded portion
having an outer circumference and an inner circumference and
adapted to mount to a wheel rim to support a deflated tire when the
tire is rolling on a surface, the molded portion having a colored
indicator that indicates at least one attribute of the RFT
support.
14. The RFT support of claim 13, wherein the colored indicator is
applied to the molded portion after molding.
15. The RFT support of claim 13, wherein the colored indicator is
formed in the molded portion by a colorant added in a molding
process of the molded portion.
16. The RFT support of claim 15, wherein the colored indicator is
formed by adding to either an A-side or a B-side or a combination
thereof in a reaction injection molding (RIM) process.
17. The RFT support of claim 13, wherein the colored indicator is
substantially uniform across at least one surface of the molded
portion.
18. The RFT support of claim 13, wherein the colored indicator is
formed from one or more indicia and are perpendicular, parallel or
at one or more angles to a central axis of the molded portion.
Description
[0001] This application claims the benefit of U.S. Provisional
Application Ser. No. 60/231,658, filed Sep. 11, 2000; Ser. No.
60/289,958, filed May 10, 2001; and Ser. No. 60/300,887, filed Jun.
25, 2001, all incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The field of invention relates to pneumatic tires. The
invention particularly relates to run flat tire supports for
pneumatic tires.
BACKGROUND OF THE INVENTION
[0003] In past years, the automotive industry has provided spare
tires for replacement of punctured or blown out tires while
traveling. However, efforts have been made to eliminate the need
for the spare tire by providing improved designs for tires.
Specifically, efforts have been made to provide a stable and
economical tire that can run with little or no pressure when, for
example, the tire is flat. The term for the efforts has become
known as "run flat tire" (RFT) technology. The RFT concept allows
an operator to continue driving or rolling for an extended period
of time without stopping to replace the tire or seeking emergency
assistance. A tire can be repaired at a later, more convenient
time.
[0004] One embodiment of an RFT wheel assembly includes a rim, a
tire mounted on the rim, and a support sandwiched between an inner
surface of the tire and an outer peripheral surface of a rim. The
support allows the tire to deflect a limited amount so that the
tire does not separate from the rim along each edge of the tire. A
synthetic material, such as a polymer, is typically used for the
support.
[0005] The process of producing an RFT support typically involves
some type of molding. A mold for the support can include a narrow
channel of about three millimeters (mm) in width that is formed
about an inner or outer periphery of the mold. The polymer support
can be reinforced to help maintain its structural integrity during
adverse conditions by providing a reinforcement in the molding
process. The reinforcement is placed in the channel prior to
molding and the polymer typically flows therethrough to encapsulate
the reinforcement into the molded RFT support.
[0006] RFT supports can vary by manufacturer, size, style, and
other attributes. Shipping, installation, repair, and other
post-manufacturing uses need clear identification of the various
RFT supports. For example, different RFT supports can be
unintentionally and perhaps dangerously installed on improper rims
and/or tire combinations.
[0007] Therefore, there remains a need for an RFT support that
includes some visual indicator of one or more of the attributes of
the RFT support to avoid confusion with other RFT supports.
SUMMARY OF THE INVENTION
[0008] The present invention provides a unitary run flat tire (RFT)
support that includes a visual colored indicator. The colored
indicator can be formed reinforcement that is formed into a
relatively rigid shape. Generally, the unitary RFT support
reinforcement can be formed from multiple layers that are coupled
together, such as with an adhesive, to form one effective layer.
The one effective layer can include layers of cloth or,
advantageously, layers of filaments wound into a reinforcement. The
reinforcement is insertable into a mold for an RFT support and can
maintain the needed structural rigidity for such insertion.
[0009] Further, the invention provides an RFT support that is
molded and includes the RFT reinforcement. The invention also
provides a wheel assembly including a tire, a rim, and an RFT
support between the rim and the tire, where the support includes
the RFT reinforcement. The RFT support can have a colored indicator
formed or subsequently applied thereto to indicate one or more
attributes of the support.
[0010] The present invention provides a run flat tire (RFT)
support, comprising a molded portion having an outer circumference
and an inner circumference and adapted to mount to a wheel rim to
support a deflated tire when the tire is rolling on a surface, the
molded portion further comprising a colored indicator that
indicates at least one attribute of the RFT support; and at least
one RFT reinforcement molded into the molded portion.
[0011] An RFT support is provided, comprising a molded portion
having an outer circumference and an inner circumference and
adapted to mount to a wheel rim to support a deflated tire when the
tire is rolling on a surface, the molded portion having a colored
indicator that indicates at least one attribute of the RFT
support.
[0012] A method of manufacturing an RFT support is also provided,
comprising flowing a moldable material into an RFT support mold to
form the RFT support; and visually identifying at least one
attribute of the RFT support by adding a preselected colorant to at
least a portion of the RFT support.
[0013] A method of installing an RFT support on a wheel rim is also
provided, comprising selecting a wheel rim; and selecting an RFT
support suitable to the wheel rim based on a colored indicator
formed on the RFT support, the colored indicator indicating at
least one attribute of the RFT support.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic partial cross sectional view of a
wheel assembly.
[0015] FIG. 2 is a perspective schematic view of an RFT
support.
[0016] FIG. 3 is a schematic side view of another embodiment of the
RFT support.
[0017] FIG. 4 is a schematic view of an RFT reinforcement.
[0018] FIG. 5A is a schematic perspective view of another
embodiment of the RFT support.
[0019] FIG. 5B is a partial schematic cross-sectional view of an
opening formed in the embodiment shown in FIG. 5A.
[0020] FIG. 6 is a schematic view of one system for producing a
filament wound RFT reinforcement.
[0021] FIG. 6a is a detailed schematic of one embodiment of
transverse members and circumferential members and associated
winding.
[0022] FIG. 7 is a schematic view of another embodiment of a system
for producing an RFT reinforcement by wrapping reinforcement
material around a mandrel.
[0023] FIG. 8 is a schematic view of another embodiment of the
system for molding an RFT reinforcement.
[0024] FIG. 9 is a schematic view of another embodiment of the
system for producing a reinforcement having longitudinal
members.
[0025] FIG. 10 is a schematic view of another embodiment of a
system for producing an RFT reinforcement using a tangential
molding process.
[0026] FIG. 11 is a schematic perspective view of a RFT support
having a colored indicator.
[0027] FIGS. 12a-12f is a schematic perspective view of exemplary
colored indicators on a RFT support.
DETAILED DESCRIPTION OF THE INVENTION
[0028] The present invention generally includes a colored run flat
tire (RFT) support including the RFT reinforcement, and a wheel
assembly including the RFT support, tire, and rim. Further, the
invention includes methods of manufacturing the RFT support and
reinforcement.
[0029] FIG. 1 is a schematic partial cross sectional view of a
wheel assembly. A wheel assembly 10 includes a rim 12, a tire 14
mounted on the rim, and an RFT support 16 mounted between an inner
peripheral surface of the tire and an outer peripheral surface of
the rim. In some embodiments, the rim 12 can include a center
support 24 which allows attachment of the wheel assembly 10 to a
vehicle (not shown). The center support 24 can generally can be a
web, spokes, or other attachment element, and can include a
separate multi-piece element, as is known in the commercial
trucking industry for wheel assemblies. The rim 12 also includes a
first rim flange 26 and a second rim flange 28. The outer diameter
of the RFT support 16 is generally the same or greater than the
inner diameter of the tire 14 at the beads 30 and 32. The RFT
support 16 is generally compressed circumferentially in at least
one direction to an elliptical shape so that the RFT support can be
inserted within the tire 14 generally prior to insertion of the RFT
support onto the rim 12. Thus, the support 16 should be relatively
rigid to support a load of the tire in an underinflated condition,
but is also sufficiently flexible to allow changing the shape for
installation. The materials for the RFT support are discussed in
reference to FIG. 2.
[0030] The RFT support 16 includes an outer hoop 18, and inner hoop
20, and a center web 19 disposed therebetween. Further, the RFT
support 16 includes at least one RFT reinforcement 22 molded
therein. The RFT support can have a colored indicator on one or
more of the RFT support surfaces as described more fully in
reference to FIGS. 11-12.
[0031] The RFT Support
[0032] FIG. 2 is a perspective schematic view of an RFT support 16,
shown in FIG. 1. The RFT support 16 includes in one embodiment an
outer hoop 18 generally having a tire support surface 15 for the
tire 14 that is shown in FIG. 1, an inner hoop 20 generally having
a rim support surface 21 for the rim 12 that is also shown in FIG.
1, and a center web 19 disposed therebetween.
[0033] At least one RFT reinforcement 22 is molded into the RFT
support. Generally, the RFT reinforcement is molded into the inner
hoop 20, although the reinforcement could be molded in other areas
of the support, including the outer hoop 18 and the center web 19.
Further, multiple RFT reinforcements can be molded at more than one
position in the RFT support. For example, multiple RFT
reinforcements could be molded at either different diametrical
spacings or different lateral spacings, such as side-by-side, in
the RFT support.
[0034] Generally, the RFT reinforcement is formed into a unitary
member, in that, the reinforcement is a substantially continuous
member, such as a cylinder, having one effective layer prior to
inserting the reinforcement in a mold for molding. If the RFT
reinforcement is formed from a plurality of elements or layers,
then generally the elements or layers are coupled together through
mechanical attachment, chemical attachment, such as with coatings
that would include binders, adhesives, and other substances that
cause adherence between at least two elements or layers, or other
methods that would join such portions together to form one
effective layer. The reinforcement does not need coupling around
the entire periphery to be considered having "one effective layer"
for the purposes of this invention. Rather, such term is defined
functionally, in that the reinforcement is coupled together
sufficiently, so that it can be held together without substantial
delamination, as described herein. Advantageously, the
reinforcement can be coupled around at least the majority of its
periphery. Generally, the coupling of the multiple layers together
should be sufficient to remain intact during customary handling
procedures of a manufacturing process, so that the layers do not
delaminate. Delamination can cause delays in a manufacturing
process during insertion of the reinforced member into the RFT
support mold.
[0035] The loft of the material used in the RFT reinforcement can
be reduced in some embodiments, especially when a coating is used
to reduce the thickness of the material and/or to retain fibers to
adjacent fibers. The thinner material can assist in placement in a
mold. The reinforcement 22 assists in resisting crack propagation
in the RFT support and otherwise contributes to the structural
integrity of the support 16, particularly when the support 16 is
mounted on the rim 12, shown in FIG. 1, and placed in use.
[0036] The center web 19 can include openings 40 to achieve weight
reduction and material savings. The openings 40 can be any
geometric shape and generally are round, elliptical, square,
triangular, rectangular, parallelogram, rhombus, or diamond shaped.
The center web 19 can be made of a flexible material to allow
flexing of the support for installation in the wheel assembly 10,
described in reference to FIG. 1.
[0037] The support 16 can be formed through molding and one
embodiment is formed through reaction injection molding (RIM), a
technique known to those with ordinary skill in the art. For the
purposes of this disclosure, RIM can also include, without
limitation, variations such as structural reaction injection
molding (SRIM) and reinforced reaction injection molding (RRIM).
Other methods can include resin transfer molding (RTM),
thermoplastic injection molding, blow molding, rotational molding,
foam molding, bead foam molding, compression molding, profile
extrusion, and spin casting. These various techniques are known in
the industry for producing molded parts. The material for the RFT
support can be any moldable material. Suitable materials for use in
preparing these RFT supports include, for example, the classes of
thermoplastic elastomers commercially available according to the
"Handbook of Thermoplastic Elastomers," 2nd Edition, edited by B.
M. Walker and Charles P. Rader, Van Nostrand Reinhold, New York,
1988. These are: styrenic block copolymers; rubber-polyolefin
blends; elastomeric alloys; thermoplastic polyurethanes;
thermoplastic copolyesters; and thermoplastic polyamides. Under the
category of elastomeric alloys, there are thermoplastic
vulcanizates (TPVs) and melt processable rubbers (MPRs). Other
useful materials can include polyvinyl chloride; polyethylene
copolymers (including ethylene/styrene copolymers via constrained
geometry catalysis); hydrogenated styrene block copolymers;
polylactic acid polymers; and ethylene/carbon monoxide
copolymers.
[0038] There are also a number of thermosetting or vulcanizable
elastomers commercially available according to "Rubber Technology;"
3rd Edition, edited by M. Morton, Kluwer Academic Publishers,
Boston, 1999 which can be used to prepare the RFT supports. These
elastomers include natural rubber (cis-1,4-polyisoprene);
styrene-butadiene rubbers; polybutadiene rubbers; polyisoprene
rubbers; ethylene-propylene rubbers, polychloroprene polymers;
chlorinated polyethylene; chlorosulfonated polyethylene; silicone
rubbers; flurocarbon elastomers; polyurethane elastomers;
polysulfide elastomers; hydrogenated nitrile rubbers; propylene
oxide polymers (vulcanizable copolymers of PO and allyl glycidyl
ether); epichlorohydrin polymers; and ethylene acrylic elastomers
(ethylene/methyl acrylate/carboxylic acid containing monomer
terpolymers). Another material is polycoprolactam/polyether
copolymers, such as NYRIM.RTM.. Curing, as appropriate, can be
accomplished through self-cure, catalytically induced cure, thermal
cure, photo sensitive cure, free radically initiated cure, actinic
cure, such as X-ray cure, electron beam cure, microwave cure, and
other cures known to those of ordinary skill in the art.
[0039] Further, exemplary polyurethanes suitable for the RFT
support can include at least one polyol, at least one chain
extender, and at least one isocyanate. Such polyurethanes include
those materials cited and prepared in accordance the disclosure in
PCT application WO 01/42000, by The Dow Chemical Company of
Midland, Mich., USA, the assignee of the present invention.
[0040] PCT publication WO 01/42000 describes polyurethane-polymer
compositions that are useful for making a lightweight tire support.
Example 1 of this PCT publication describes one composition that
can be particularly useful, although other materials can be used.
In Example 1, a polyurethane-polymer composition was prepared by
admixing a polyol-side stream and an isocyanate-side stream using
reaction injection molding.
[0041] The polyol-side stream included a polyol formulation. The
polyol formulation included a polyol in an amount of 54.81 weight
percent, a chain extender in an amount of 44.84 weight percent, a
surfactant in an amount of 0.25 weight percent, and a catalyst in
an amount of 0.1 weight percent.
[0042] For the polyol formulation, the polyol was an ethylene-oxide
capped 5,000 molecular-weight triol having a maximum unsaturation
of 0.035 milliequivalents per gram of the total composition
(available from The Dow Chemical Company, Freeport, Tex.). The
chain extender was diethyl toluene diamine (a mixture of
3,5-diethyl-2,4- and 2,6'-toluene diamines) (available from The Dow
Chemical Company, Freeport, Tex.). The surfactant was a silicone
surfactant (L-1000; available from OSI Specialties/Witco Corp.,
Chicago, Ill.). The catalyst included a 50:50 combination of
triethylene diamine (Dabco 3LV) (available from Air Products and
Chemicals, Inc., Allentown, Pa.) and dibutyl tin dilaurate (Fomrez
UL28) (available from Witco Chemical Co., Chicago, Ill.)
[0043] The isocyanate-side stream included a prepolymer
formulation. The prepolymer formulation included a first isocyanate
in an amount of 31.83 weight percent, a polyol in an amount of
63.17 weight percent, and a second isocyanate in an amount of 5.0
weight percent.
[0044] For the prepolymer formulation, the first isocyanate was 98
percent pure p,p'-MDI (Isonate 125M) (available from The Dow
Chemical Company, Freeport, Tex.). The polyol was an ethylene-oxide
capped (15 percent) 6,000 molecular-weight triol with a maximum
unsaturation of 0.02 milliequivalent per gram of total composition
(available from Asahi). And the second isocyanate was 50 percent
p,p'-MDI and 50 percent o,p-MDI (Isonate 50 OP) (available from The
Dow Chemical Company, Freeport, Tex.).
[0045] The isocyanate-side stream and the polyol-side stream were
combined in a weight-ratio blend of 2:15:1 (isocyanate to polyol)
using standard reaction-injection-molding processing
conditions.
[0046] One skilled in the art will recognize that the formulation
in this example can vary for the purposes of the present invention.
For example, testing conditions, tolerances in formulation of raw
materials, and variances with processing can alter the composition
within acceptable ranges. Further, the formulation can be modified
to alter properties of the tire support, such as but not limited
to, altering the ratio of chain extender and polyol, eliminating a
second isocyanate, and using polyols that are not ethylene-oxide
capped. Still further, the ranges given in the PCT publication WO
01/42000 can also produce other suitable formulations.
[0047] FIG. 3 is a schematic side view of another embodiment of the
RFT support. The RFT support 16 in the embodiment shown in FIG. 3
includes a set of components that can be molded in separate
operations. The RFT support 16 includes an outer hoop 18, a center
web 19, and an inner hoop 20, which in at least one embodiment
includes an RFT reinforcement 22. In some embodiments, the hoops
and/or web can be formed from one or more thermoplastic foams, such
as elastomer bead foams. Optionally, the hoops and/or web can be
unfoamed. For example, the inner hoop 20 can be formed of a dynamic
thermoplastic foam.
[0048] The density can be controlled to provide a relatively rigid
inner hoop. The RFT reinforcement 22 can be formed of a fibrous or
other suitable material and, in at least one embodiment, is coupled
to the inner hoop by being affixed or molded therein. The center
web 19 can be formed of a lower density dynamic thermoplastic foam.
The center web 19 can optionally contain load bearing optimized
openings (not shown) for weight reduction. The outer hoop 18 can be
a higher density dynamic thermoplastic foam. The combination can
provide sufficient strength to the inner surfaces, such as the
inner hoop 20, and still be sufficient to allow the shape to change
as needed for installation of the RFT support into the tire 14 and
onto the rim 12, as shown in FIG. 1.
[0049] The hoops and/or web can be molded using a conventional
molding, such as foam or bead foam molding techniques known to
those with ordinary skill in the art. For example, a portion of the
inner hoop 20 can be formed and an RFT reinforcement 22 placed
around the portion to form the inner hoop. The inner hoop 20 can
optionally be prepared using a profile extrusion system. The inner
hoop 20 could be reinforced by the RFT reinforcement 22 molded
therein. The center web 19 can be molded around the inner hoop 20
and the RFT reinforcement 22. The outer hoop 18 can be molded
around the center web 19.
[0050] One skilled in the art having read this specification would
understand that the RFT reinforcement 22 can be disposed in other
positions in the RFT support 16. For example, the RFT reinforcement
can be disposed or otherwise formed in or adjacent to the outer
hoop 18 or the center web 19.
[0051] RFT Reinforcement
[0052] FIG. 4 is a schematic view of an exemplary rigid, unitary
RFT reinforcement. The RFT reinforcement 22 generally includes at
least one transverse member 42. In the embodiment shown, a second
transverse member 42a intercepts the transverse member 42. Further,
the reinforcement 22 can include at least one substantially
circumferential member 44. In at least one embodiment, the
transverse members 42, 42a can be wound symmetrically, that is, at
similar angles with respect to a center axis 23. Transverse angles
.alpha..sub.1, .alpha..sub.2 can be used to describe the angle of
the transverse members 42, 42a, respectively, relative to the
center axis 23. In one embodiment, the transverse angles can be
more than about 0 degrees to less than about 90 degrees, and
advantageously about 70 degrees to about 80 degrees, such as about
78 degrees. Alternatively, the angles can be different from each
other. One exemplary spacing 43 between adjacent transverse members
can be about 20 mm to about 30 mm, such as about 24 mm. The
transverse members can be a variety of widths and in at least one
embodiment can be between about 2 mm to about 5 mm, such as about 3
mm.
[0053] Similarly, in at least one embodiment, the circumferential
members 44 can be a width generally of about 2 mm to about 10 mm,
such as between about 5 mm to about 8 mm. The circumferential
members can be equally or non-equally spaced across a width of the
RFT reinforcement of about 70 mm to about 120 mm, such as about 90
mm. A circumferential angle .beta. can be used to describe the
angle of the circumferential member(s) and generally is a large
angle, that is, almost perpendicular to the axis 23, although any
angle between about 0 degrees and about 90 degrees can be used. In
at least one embodiment, the angle .beta. can be between about 80
degrees to about 90 degrees.
[0054] It would be understood to one with ordinary skill in the art
that the above dimensions are exemplary and the angles, uniform and
nonuniform spacings, sizes, number of members and other dimensions
can all vary depending on various design parameters, such as
materials, desired rigidity, ease of assembly, costs, and strength.
Further, the transverse members and circumferential members can be
formed for different filaments or from a common filament, as
described below regarding FIG. 6.
[0055] The RFT reinforcement of the present invention
advantageously has a higher rigidity than found in prior efforts.
The higher rigidity allows the reinforcement to be manually or
automatically handled and to be placed relatively quickly in
position in an RFT support mold. The speed and efficiency improves
the productivity of an RFT support which should, in turn, allow for
the economic production of the mass quantities of supports required
for the transportation market.
[0056] A prior art RFT reinforcement comprising multiple layers of
a scrim cloth took about 45 seconds to place in an RFT support mold
in one comparative test. In contrast, some tests using at least one
embodiment of the RFT reinforcement disclosed herein took about
10-15 seconds or less to place in the mold, that is, less than
one-third of the time using the prior art. Even more
advantageously, the tests showed that it was possible to reduce the
time to about 2-5 seconds or less and generally about 3 seconds or
less, that is, about an order of magnitude difference in time from
the prior art.
[0057] Initial tests were conducted in manually placing the RFT
reinforcement described herein in the mold. Automatic placement can
also benefit using the RFT reinforcement described herein, for
example and without limitation, through robotic placement or other
automatic or semi-automatic placement systems.
[0058] The RFT reinforcement can also contain openings 46 formed
therethrough. The openings allow liquid reactants to penetrate the
reinforcement during the molding process of the RFT support, so
that the reinforcement becomes an integral part of the RFT support
when the liquid reactants solidify. Preferably, the reinforcement
is substantially encapsulated by the polymer.
[0059] The RFT reinforcement can be made from a variety of moldable
and metallic materials. For example, the transverse members and/or
circumferential members can be made of fiberglass, carbon/graphite
fibers, aramid fibers, polyester fibers, metal fibers and other
materials. The types of fibers can be combined into composites to
include combinations of glass, carbon/graphite, aramid, polyester,
metal and other materials. The material can include metallic cloth
materials, such as wire mesh, or solid rings. The fibers can
additionally include a binder, sizing, dressing, or other coating
to facilitate processing, binding or heat sealing of the
fibers.
[0060] The individual fibers can be formed into filaments or tape.
The fibers can be cut into discrete layers to produce cut fibers
and can be included in a moldable material. In this disclosure, the
term "filament" is used broadly and includes ribbons, fibers,
tapes, yam, tow, roving, and other individual, or groups of,
materials to be wound about the mandrel. Unless explicitly stated
herein, the term "mandrel" includes a member around which the
filaments or other material are wound or formed. The mandrel can be
reused for subsequent winding or forming, or can be integrated into
the RFT reinforcement and/or RFT support in the processing of the
same, for example, by cutting the member as a portion of the RFT
support or RFT reinforcement. A collapsible mandrel can be used to
advantage to facilitate the removal of the RFT reinforcement.
[0061] Additional materials for the reinforcement can include thin
strands of wire woven into the material. Further, the reinforcement
can be made from sheets, and in some embodiments laminated sheets.
The RFT reinforcement can also be made of reinforced thermoplastic
containing fibers. For example, the fiber composition of the
thermoplastic can range from about 20% to about 99%, although other
percentages are possible. Generally, the RFT reinforcement
comprises a weight per square meter of about 50 grams to about 1000
grams per square meter.
[0062] An important aspect is that the reinforcement be
sufficiently rigid to allow relatively quick and easy insertion
into the mold and still be sufficiently flexible to allow
compression of the RFT support for installation of the RFT support
into the wheel assembly, shown in FIG. 1. Further, the
reinforcement can be sufficiently rigid to help provide structural
resistance to the otherwise outward expansion of the molded support
during rotation and the accompanying outward centrifugal forces,
such that the support substantially maintains its structural
integrity during its intended use. For purposes herein, such
stiffness will be referred to as "hoop stiffness," that is, the
ability to resist an outward expansion due to rotating radial
forces.
[0063] To increase hoop stiffness, the fibers can have a coating
applied through spraying, dipping, encapsulating, extruding,
impregnating, combining with films, or other methods known to those
in the art that are available before or after the fibers are formed
into an appropriate shape for the RFT reinforcement to produce a
self-supporting structure that is capable of not collapsing when
the structure is without external supports. Further, the
reinforcement material could be dipped in a coagulation dip coating
prior to forming around a mandrel and a relatively rigid polymer
could be applied to act as an aqueous dispersant to provide
suitable the self-supporting structure. The reinforcement
preferably advantageously has a balanced weight distribution around
the reinforcement periphery to assist the centrifugal balance of
the final RFT support during driving conditions.
[0064] The RFT reinforcement can be made in individual units or can
be made as a tubular member and one or more reinforcement units cut
from the tubular member. The RFT reinforcement can be filament
wound about a mandrel. Alternatively, the RFT reinforcement can be
made from prepared cloth or sheets that are rolled into a desired
shape and the ends or other portions of the material coupled to
each other. The term "coupled," "coupling," and like terms as used
herein includes adhering, bonding, binding, curing, fastening,
attaching, and other forms of securing one piece to another
piece.
[0065] FIG. 5A is a schematic prospective view of another
embodiment of the RFT reinforcement 22. In this embodiment, the RFT
reinforcement 22 includes a relatively solid member that can be
perforated with openings 46. The term "opening" and like terms are
used broadly and include any aperture formed in the support and/or
reinforcement, such as holes, slots, and other apertures. The term
"perforate" and like terms are used broadly and include any method
for forming openings in a material, such as molding, drilling,
stamping, punching, melting, and other aperture forming
methods.
[0066] Openings 46 allow the molding material to flow therethrough.
Advantageously, the openings allow the molding material to flow
through and around the reinforcement 22, so that the reinforcement
22 is at least partially encapsulated, and preferably substantially
encapsulated, by the molding material. It is to be understood that
the openings are optional and other embodiments may not have
substantial openings.
[0067] As an example, the RFT reinforcement can be made from a
relatively thin tube of material and processed by punching,
drilling, cutting or otherwise forming openings 46. The material
can be metal, composites, fiber reinforced composites, plastics, or
other material that can be shaped into an essentially circular
form. The terms "circular" and "cylindrical" are used broadly and
include any shape forming a loop without hard corners, such as
circles, ellipses and irregularly shaped geometric figures.
[0068] FIG. 5B is a partial schematic cross-sectional view of an
opening 46 formed in the RFT reinforcement shown in FIG. 5A. A
surface 48 of the RFT reinforcement 22 has been perforated. In at
least one embodiment, the surface 48 can be perforated, so that a
tab 50 is disposed adjacent surface 48 to form the opening 46. The
tab 50 can be useful in increasing a coupling force to subsequent
molded material of the inner hoop 20 that surrounds the
reinforcement, shown in FIGS. 1 and 2. The tab can also be useful
is locating the reinforcement in a mold. The tab can extend in any
direction, including toward the center of the reinforcement. In
other embodiments, the opening 46 can be formed without producing a
tab 50.
[0069] One property indicating suitable rigidity of the RFT
reinforcement 22 is by measuring the deformation in a drop test. A
test regimen for the reinforcements was to form a cylindrical
reinforcement and determine the average diameter of the
reinforcement from side to side when the reinforcement was lying
horizontally in a state of rest. The reinforcement was rotated
vertically, that is, the axis 23 that is shown in FIG. 4, was
substantially perpendicular to gravity and elevated, so that a
lower portion of reinforcement was at a height of about two meters
above an uncushioned concrete floor. Other hard surfaces could also
be used, such as wood, metal, or relatively rigid polymer surfaces.
The reinforcement was dropped to test the amount of deformation
occurring after the drop when the reinforcement was again lying
horizontally in a state of rest.
[0070] Generally, the resulting shape was elliptical rather than
circular. The dimensions of the resulting ellipse were measured
after recovery when the reinforcement was again horizontal in a
state of rest. The resulting dimension from side to side of the
reinforcement after the drop generally decreased in a direction of
the drop or increased in a corresponding amount in a direction
perpendicular to the drop. A difference between either the
decreased amount in one direction or the increased amount in the
other direction compared to the original average diameter was used
to calculate an average deformation percentage. The reinforcement
was then reshaped into a circle prior to the next test. The test
was repeated several times. Additionally, any delamination was
noted as would cause the RFT reinforcement to be difficult to
insert into a mold.
[0071] It was found that if the deflection percentage was about 20%
or less, then the reinforcement generally had a rigidity that
allowed the reinforcement to be inserted relatively easily into the
support mold. Naturally, the deflection percentage could be more
and still be usable. An advantageous percentage was about 10% or
less, a more advantageous percentage was about 5% or less, and an
even more advantageous percentage was about 1% or less. Some
examples of various reinforcements that were prepared, tested, and
inserted into the support mold in order to mold a support are
described herein.
[0072] The reinforcement can be produced by several methods, some
of which are described below. Generally, the reinforcement can be
produced individually, or can be produced as from tubular members
and individual reinforcements cut therefrom. As used herein, "cut"
includes any type of severing of one piece from another. For
example and without limitation, the cut could be performed by a
cutter, such as a saw with one or more abrasive wheels.
[0073] FIGS. 6-10 show at least five variations of forming the
reinforcements. Some of the variations include, for example,
filament winding around a mandrel, wrapping a material around a
mandrel, molding a reinforcement in a die, supplying longitudinal
members in the winding of a reinforcement, and tangentially molding
a reinforcement. Naturally, other methods are possible and the
examples herein are non-limiting.
[0074] FIG. 6 is a schematic view of one system for producing a
filament wound RFT reinforcement 22 shown in FIGS. 1-5B by a
filament winding method and system. The system 60 includes a
support mandrel 62, one or more reinforcement supplies 64, 66, and
68, such as drums or reels, a heater or other curing element(s) 76,
and can include a cutter 80. The support mandrel 62 provides a
surface about which filaments from the reinforcement supplies can
be wound.
[0075] In at least one embodiment, one or more reinforcement
supplies 64, 66 can be used to wind the filaments around the
mandrel in a transverse direction at an angle to the center axis of
the mandrel. The angle depends upon the speed of the rotating
mandrel coupled with the speed at which the reinforcement supplies
and/or material move along the axis of the mandrel. The angle would
generally be between about 0 degrees and about 90 degrees and
generally is between about 45 degrees and about 90 degrees.
Further, an angle between intersecting filaments can be varied. For
example, the transverse members 42, 42a shown in FIG. 4 can
intersect at angles from greater than about 0 degrees to less than
about 180 degrees.
[0076] In at least one embodiment, a reinforcement supply 68 can
provide a substantially circumferential band of filaments. The band
of filaments forms the one or more circumferential members 44,
shown in FIG. 4. Generally, the circumferential member(s) 44 can be
formed by winding the filaments at a large winding angle, i.e.,
almost perpendicular angle to the mandrel axis, to form a
substantially continuous winding of filaments and spacings from
multiple revolutions of the filaments around the mandrel, although
any angle between about 0 degrees and about 90 degrees can be used.
Thus, the circumferential member(s) 44 can be a continuous band
that progressively is wound along the mandrel in at least one
embodiment. Further, the circumferential member can be formed from
one or more wraps, such as two, three, or more wraps to increase a
hoop strength of the circumferential member. Alternatively, the
filaments can be wound in discrete sections and cut to form a
circumferential member and then the reinforcement supply 68
incrementally positioned to wind another circumferential member
along the mandrel. Further, the filaments can be wound in multiple
layers and/or widths to form a variety of thicknesses and widths of
circumferential members and coupled to create the one effective
layer described herein. Still further, the filaments can be wound
at different rates of traverse, so that some filaments are wound
closer together than other filaments. An example is described in
reference to FIG. 6a.
[0077] Thus, the RFT reinforcement can be formed as an assembly of
transverse and circumferential members. The geometry of the wound
filaments on the mandrel can leave openings for moldable material
to pass therethrough in molding the RFT support. Further, various
lengths of the RFT reinforcement can be made on the mandrel,
including single RFT reinforcements or multiple widths of RFT
reinforcements that can be cut into individual RFT reinforcements
through processing.
[0078] It is to be understood that variations of the winding are
contemplated by the invention. For example, the various figures and
methods described herein can use one or more of the reinforcement
supplies, alone or in combination, to form various combinations of
one or more transverse and/or circumferential members. Further,
several reinforcement supplies are shown, but the number is not
limiting and can vary depending on the various capabilities and
production requirements. Also, the speeds and feeds of the various
supplies can be varied as appropriate to produce desired
thicknesses, spacings, shapes, and so forth, as would be apparent
to those with ordinary skill in the art, given the understanding
provided by the description of the invention contained herein.
[0079] In at least one embodiment, one reinforcement supply can be
used to produce the transverse members by traversing the mandrel in
one direction while winding and then traversing in another
direction to produce another transverse member at a different
angle. Further, the same reinforcement supply can be used to wind
the transverse member or members and the circumferential members,
for example by changing the traverse or rotation speeds for the
transverse members compared to the circumferential members.
[0080] Such production capabilities in accordance with the
teachings of the present invention and any associated software as
could be performed by those with ordinary skill in the art, having
been shown the underlying purposes and intent of the present
invention, can be included with a production machine. One
commercially available filament winding system is available from
Sidewinder Filament Winding Systems of Laguna Beach, Calif.,
USA.
[0081] Returning to FIG. 6, one or more of the reinforcement
supplies can pass through an applicator. For example, an applicator
70 is coupled to the reinforcement supply 64, an applicator 72 is
coupled to the reinforcement supply 66, and applicator 74 is
coupled to the reinforcement supply 68. The filaments pass through
the applicators and become coated with material, such as a
thermoplastic or a thermoset polymer, and then are wound onto the
mandrel. The coating material can include, for example and without
limitation, an epoxy resin, including a vinyl epoxy ester resin,
monomer, monomer mixture, polyurethane, styrene, polyester resin,
phenolic resin, polymer, or other thermoset resins, thermoplastic
resins, or combinations thereof. The applicators 70, 72 and 74 can
include bath, spray, powder coating, extruders, and other forms of
applying a material to a filament or cloth. An exemplary line of
polymer resins is a line of thermoset vinyl epoxy ester resins
known as Derakane.RTM. resins that are manufactured by The Dow
Chemical Company, such as Derakane.RTM. 411, 510N, Momentum, and
other resins suitable for coating a material and causing adherence
to adjacent materials.
[0082] The coating materials, used in their appropriate curing
system, are then allowed to cure to form a tubular member 78
through active methods, such as induced activation, or passive
methods, such as allowing the cure in ambient conditions. For
example, in active methods, a thermoplastic may need to be
crosslinked by passing the mandrel through the curing element 76,
such as a heater or a source of actinic radiation. Other catalytic
reactions can occur without the necessity of heat or actinic
radiation. Further, some resins can be cured with ultraviolet
radiation, X-rays, and other activation methods of a curable
polymer.
[0083] The tubular member 78 can be any length desired. For
example, the tubular member can be formed a sufficient length to
produce multiple sections and then cut into individual
reinforcements. Alternatively, the tubular member can be formed to
a sufficient length necessary for an individual reinforcement.
Either alternative can use any of the methods described herein.
[0084] The tubular member 78 can be brought to a cutting station of
the system 60 which includes a cutter 80. The cutter 80 severs one
or more portions of the tubular member 78 to form a unitary,
relatively rigid reinforcement 82. The tubular member can be cut on
the mandrel or can be self-supporting and removed from the mandrel
prior to cutting. The reinforcement 82 can then be used in forming
the RFT support 16 shown in FIGS. 1-3.
[0085] A variation in the method described relative to FIG. 6
includes providing a thermoplastic film or other polymeric material
on the mandrel 62 prior to winding the filaments from the
reinforcement supply 64, 66, and 68. The filaments are wound onto
the mandrel 62 without necessitating passing the filaments through
the applicators 70, 72 and 74. Stated differently, the coating is
applied to the filaments from the polymeric material on the
mandrel. The wound and coated filaments can be cured as described
above. Alternatively, the polymeric material can be provided after
the filament material is wound on the mandrel by a number of
methods, including applying a polymeric film over the filament
material, spraying, dipping, or otherwise coating the material.
[0086] Another variation is to apply the polymeric material or
other coatings to the filaments prior to winding the filaments.
Such materials, known as pre-impregnated ("pre-preg") materials,
can be partially cured and then subjected to final curing after
assembly. The resin can be cured by reaction, actinic curing, such
as ultraviolet or X-ray curing, heat, or other curing methods.
[0087] In one embodiment, the applicators can use a pultrusion
method to apply a coating to the material. As is known to those in
the art, a pultrusion method is essentially a continuous molding
process. Reinforcing fibers, such as glass fibers, or other
materials are pulled through an applicator such as a resin bath or
thermoplastic extruder to apply a coating to the material. The
material can then be used to form the RFT reinforcement. In such
embodiment, one or more of the applicators 70, 72 and 74 could
include the structure that pulls the material through the coating
process.
[0088] Further, the process could be used to form a sheet of coated
fibers. The resulting sheet could be wound around a mandrel, sealed
upon itself to produce a tubular member, and optionally perforated.
One or more RFT reinforcements can be cut from the tubular
member.
[0089] FIG. 6a is a detailed schematic of one embodiment of
transverse members 42, 42a and circumferential members 44, 44a, 44b
and associated winding. A reinforcement supply 68 can be moved
along the mandrel length to supply the reinforcement to the mandrel
62. The spacing and number of the circumferential members can
depend on the total length of the final RFT reinforcement,
structural characteristics, including the width of the
reinforcement, costs, and other factors and, thus, can vary from
time to time and from product to product.
[0090] Further, the filaments can be wound at different rates of
traverse or rotational speeds, so that some filaments are wound
closer together than other filaments. Thus, transverse members 42,
42a and circumferential members 44, 44a, 44b could be formed from
the same material during a winding process, but formed at different
winding traverses and/or speeds, so that the spacing is changed to
produce the various members.
[0091] In at least one embodiment, one or more circumferential
members 44a, 44b can be disposed adjacent the final edges of the
RFT reinforcement after cutting the RFT reinforcement to length.
Such edges can assist in placement, safety, and/or further
processing. The circumferential members 44a, 44b can be formed at
predetermined intervals, where a cutter 80 can cut the layer of
bonded traverse and circumferential members into at least one RFT
reinforcement 82, as also shown in FIG. 6. The members 44a, 44b can
be formed with a relatively small gap or even no gap therebetween
compared to gaps between adjacent circumferential members 44. Thus,
when an RFT reinforcement is cut from the tubular member 78 between
the members 44a, 44b, the RFT reinforcement is formed with a
circumferential member adjacent each cut edge. The circumferential
members on the edge of the reinforcement can offer improved edge
smoothness.
[0092] One or more of the reinforcement supplies, such as supply
68, can wind the circumferential members 44a, 44b of reinforcement
material on the mandrel in conjunction with winding the members 42,
42a by using the same material and changing the spacing between the
various members. Alternatively, the members 44a, 44b can be formed
as separate members from members 42, 42a.
[0093] In at least one embodiment, the circumferential members 44a,
44b can be formed from a single circumferential member with or
without a small gap between the majority of the windings. If the
members are formed together, then the combined width of the members
can be incrementally wider than a circumferential member 44, such
as twice the width. The cutter 80 can cut the combined
circumferential member to produce an RFT reinforcement that has a
circumferential member adjacent the cut edge(s) that can correspond
in width to the circumferential member 44. The above embodiments
are merely exemplary and the width, quantity, and placement of the
circumferential members 44a, 44b can vary relative to the
circumferential member 44.
[0094] FIG. 7 is a schematic view of another embodiment of a system
for producing an RFT reinforcement by wrapping reinforcement
material around a mandrel. A reinforcement supply 64 provides
reinforcement material, such as one or more filaments, cloths, or
other material, to a mandrel 62. The reinforcement material is
wrapped one or more times about the mandrel and can be cut by
cutter 88. A polymer supply 90 provides a polymeric material in a
form of, for example, a thermoplastic film, a molten web, an
adhesive tape, or other suitable media for application to
reinforcement material. The polymeric material can be wound around
the mandrel with the reinforcement filament from the reinforcement
supply 64. The polymeric material can be cut by cutter 92 to an
appropriate length. The reinforcement filament and polymer can be
pressed together by a roller 94 placed against the mandrel 62. The
materials form a tubular member 78 which can be cured and if
necessary cut to an appropriate length to form a RFT reinforcement,
as described in FIG. 6. The order of the materials can be reversed,
so that the filament is wrapped after the polymer. Thus, the
materials that are wrapped on the mandrel can be wrapped directly
or indirectly on the mandrel herein. Further, the polymer supply 90
can provide a fluid, such as in a spray, and apply the fluid to the
mandrel and/or reinforcement.
[0095] A prefabricated scrim material having apertures formed
therein can be used for the RFT reinforcement material. The
material can be wrapped more than once around the mandrel and,
thus, the apertures on the scrim material might not align with the
underlying apertures of the previous layer. The misalignment can
cause unintended restricted flow of material through the
reinforcement, so that the structural integrity of the molded RFT
support can be affected. Therefore, a mandrel can be used with
indexed "teeth" to align fibers, woven material, or other material
being wound or otherwise placed on the mandrel. Alternatively,
sufficiently large apertures can be used, so that the apertures
will not become unduly restricted through the various layers.
[0096] Alternatively, the material can be treated with a pressure
sensitive adhesive around a mandrel, causing the material to be
coupled to itself. In this method, at least one complete wrapping
of material is used to allow some surface area by which the
material can adhere to itself to form a tubular member and
ultimately the RFT reinforcement.
[0097] FIG. 8 is a schematic view of another embodiment of the
system for molding an RFT reinforcement. The system 60 includes a
support mandrel 62 and one or more reinforcement supplies 64, 66.
The reinforcement supply provides reinforcement material, such as
filaments or cloth, to wind around the mandrel 62 to produce a
wound portion 96. The wound portion 96 is supplied to a profile
extrusion die 98 having an inner and/or outer die. An extruder 100,
for example, a thermoplastic extruder, is coupled to the profile
extrusion die 98 for providing molding material as a coating
thereto. A blowing agent supply 102 can also be coupled to the
profile extrusion die 98. The profile extrusion die provides the
moldable material to the wound portion 96 in a controlled shape and
produces a tubular member 104. The tubular member 104 can be
conveyed through a cooler 106 that can also include support for the
molded RFT reinforcement in the cooling process. If desired, the
tubular member 104 can pass through a perforator 108 to provide
perforations for the tubular member 104, so that moldable material
used to manufacture the RFT support 16 shown in FIG. 1 can flow
therethrough. The tubular member 104 can progress to a cutting
station having a cutter 110 to cut a portion of the tubular member
into one or more RFT reinforcements 112. The cut piece can be
further shaped via compression or thermal shaping if necessary. The
order of the profile extrusion die, cutter, cooler, and perforator
can be varied to produce the RFT reinforcement.
[0098] A variation of the above method can include forming a
combination of extruded or prefabricated thermal plastic films with
reinforcing fabric in a relatively flat orientation. The film and
fabric can be wound by being rolled into a tube using shaping
equipment (not shown).
[0099] FIG. 9 is a schematic view of another embodiment of the
system 60 for producing a reinforcement 82 having longitudinal
members. The system is similar to the system described in FIG. 6.
The system includes a mandrel 62 about which is formed a matrix of
wound filaments. One or more reinforcement supplies 64, 66 provide
one or more transverse members of filament material around the
mandrel 62. Further, one or more reinforcement supplies 130, 132,
134, and 136 provide one or more longitudinal members. Although
various numbers of reinforcement supplies are shown, the number can
vary from one to any number as appropriate in this and any other
embodiment disclosed herein.
[0100] The mandrel 62 can include a film, a molten web, or adhesive
tape to maintain the location of the filaments prior to curing. In
at least one embodiment, the mandrel does not rotate relative to
the reinforcement supplies 130, 132, 134 and 136 while the
longitudinal members are placed. In other embodiments, one or more
of the reinforcement supplies can rotate about the mandrel. Still
further, in other embodiments, both the mandrel and the
reinforcement supply or supplies can both rotate.
[0101] The reinforcement supplies 64 and 66 provide filament
material to the mandrel as the mandrel and/or the reinforcement
supplies 64, 66 are rotated relative to the mandrel. The
longitudinal members can include a fusible polymer to hold
transverse members in position. Alternatively, an applicator 138 is
provided to spray, flow, or otherwise apply a material to the wound
portion 140. The wound portion is allowed to cure. For example, if
a thermoplastic is used, the wound portion 140 can be placed in a
curing element 76 to melt, fuse, or crosslink the thermoplastic.
The resulting tubular member 142 can be removed from the mandrel
and cut into the discrete sections to form the RFT reinforcement
82.
[0102] FIG. 10 is a schematic view of another embodiment of a
system for producing an RFT reinforcement using a tangential
molding process. Generally, the tangential molding process can use
a thermoplastic or other polymeric material that is injected into a
mold. One or more portions of the mold can rotate so that the
injected material is forced around the mold's perimeter. The
rotation causes the polymer to flow around the mold to align
entrained filaments along a circumference of the mold. The molded
part can be allowed to cool and solidify and the RFT reinforcement
removed from the mold with the filaments in appropriate alignment.
Openings in the molded part can be formed to allow molding material
for the RFT support to flow therethrough in the subsequent support
molding process.
[0103] A mold 116 can include one or more sides 118, a bottom 120,
and a top 124. A support 122 can support one or more portions of
the mold 116. A shaft 126 can be inserted through the top 124. One
or more seals, such as seals 115, 117, 119, and 121, can be
disposed at various interfaces between the shaft 126, top 124,
sides 118, and bottom 120. The seal(s) can include a bearing. One
or more motors 123, 125 can be used to rotate and/or translate
portions of the mold. The motors can be coupled to a controller 127
for control thereof. An injection point 129 coupled to one or more
portions of the mold 116 can be used to introduce the molding
material into the mold.
[0104] In operation, the molding material is introduced into the
mold and the shaft can be rotated. The fluid properties of the
molding material in conjunction with the rotating shaft cause the
molding material to accumulate adjacent the sides 118. Filaments
entrained in the molding material can also become aligned around
the circumference of the sides 118. The molded part is allowed to
solidify and removed from the mold. For example, the bottom 120 can
be separated from the top 124 and the molded part removed from the
mold.
[0105] Variations are possible. For example and without limitation,
the shaft 126 can be stationary and one or more other portions of
the mold 116, such as the sides 118, can rotate around the shaft.
Further, the shaft and the one or more other portions of the mold
can rotate together or in opposite directions. The shaft 126 can be
inserted through the bottom 120, the sides can be coupled to the
top 124, the ports can be in one or more alternative positions such
as 129a, 129b, 129c or combinations thereof. Multiple injection
points can be used. The angles of the injection points can also
vary. For example, one or more injection points can be angled along
the side of the mold to assist in prealigning the material, as it
is introduced into the mold. Injection is used broadly and includes
herein any known method of introducing a molding material into a
mold. Other equipment (not shown), such as heaters, coolers, and
electrical controls could vary the production of the
reinforcements. The schematic is used to illustrate a tangential
molding method and is not limiting of the underlying method of a
tangential molding method, as many variations are possible.
[0106] It is to be understood that a similar result can include
using a tangentially directed port(s) with or without the mold or
shaft rotating. For example, a thermoplastic can be injected into
the mold in a direction that forces the polymer to flow around a
reinforcement hoop to circumferentially align entrained filaments.
As the mold is filled with material, the filaments can flow around
the circumference of the mold. The molded part can then allowed to
solidify and the RFT reinforcement removed from the mold with the
fibers in position. For the purposes of this disclosure, tangential
molding is meant to include such variations.
[0107] Colored Indicator for RFT Support
[0108] As described herein, the RFT supports can vary by
manufacturer, size, style, and other attributes. Shipping,
installation, repair, and other post-manufacturing uses can benefit
from some visual indicator of one or more of the attributes of the
RFT support to avoid confusion with other RFT supports. The present
invention provides a heretofore unknown and unused colored
indicator(s) to indicate one or more attributes of the RFT
support.
[0109] FIG. 11 is an exemplary RFT support 16 having an axis 17, an
outer periphery 141, an inner periphery 143, side walls 144, and a
preselected colored indicator 139. In some embodiments, the colored
indicator can be applied to the RFT support on one or more surfaces
of the support. In at least one embodiment, the colored indicator
can be incorporated into materials used to form the RFT support.
For example, the colored indicator can be formed into the RFT
support during a molding process of the RFT support. The colored
indicator could be mixed with the RFT support components to produce
a colored RFT support.
[0110] Where the RFT support is a polyurethane, it can be formed,
for example and without limitation, by a reaction injection molding
(RIM) process. This process is well established in the art and
consists of filling a closed mold with highly reactive liquid
starting components within a very short time, generally by using a
high output, high pressure dosing apparatus after the components
have been mixed. In one embodiment, the reaction injection molding
process consists of the use of at least two liquid streams (A) and
(B) which are impingement mixed under moisture free conditions.
Stream A contains the organic polyisocyanate, typically a liquid
polyisocyanate. Stream B contains the isocyanate-reactive component
which typically is a polyol and/or an amine polyether, and usually
a chain extender containing amino and/or hydroxyl groups. The
mixture is then allowed to cure within the mold to render the
finished product. The colorant can be added to either the "A"
component or the "B" component. Alternatively, the colorant could
be added to both the "A" component and the "B" component.
[0111] The coloring can be visually apparent on one or more
surfaces of the RFT support. Further, the coloring could be
substantially uniform across one or more surfaces of the RFT
support, especially if the coloring is substantially uniformly
mixed with the components. The coloring indicator can be a stable
or inert material, such as a dye, or can be a reactive ingredient
that can be activated chemically, electrically, photochemically,
thermally, or by any other method of causing an ingredient to
react. Further, the reactive ingredient can react with components
used in the molding process of the RFT support to produce one or
more colors.
[0112] FIGS. 12a-12f are exemplary RFT supports having variations
of colored indicators. The colored indicator can be formed, applied
thereto, or otherwise coupled with the RFT support in addition to
or in lieu of the colored indicator being incorporated into the RFT
support as described above. The colored indicator can be coupled to
one or more surfaces of the RFT support. In some embodiments, the
RFT support can be substantially covered with the colored
indicator. A substantial coverage can also form a barrier for
gaseous or liquid fluids or other substances affecting the RFT
support. In some embodiments, the colored indicator can include a
single representation or a plurality of representations of
markings, symbols, or other visually apparent indicia to indicate
the one or more attributes of the RFT support.
[0113] The colored indicator can be a uniform color that is coupled
to one or more surfaces of the RFT support. Alternatively, the
colored indicator can include variations in colors. For example, a
single indicator can be used with different colors indicating
different attributes, such as manufacturer, size, or other
attributes. More complicated schemes can be used with, for example,
multiple colored indicators having multiple colors that can be used
to indicate one or more attributes.
[0114] The colored indicator can also indicate attributes of use,
condition, wear, and other operation-related attributes. For
example, a colored indicator can be applied to the RFT support and
then change colors when one or more operation attributes occur,
such as an operating condition(s) or an event(s), that would cause
a response from the colored indicator. In at least one embodiment,
a colored indicator can change colors when a mounted tire deflates
and rolls against the RFT support during use. The wear could cause
increased heat, friction, or other phenomena and cause the colored
indicator to temporarily or permanently signal a change. Similarly,
colored indicators can be used to indicate operating wear,
unusually high stress, and other operating conditions.
[0115] Further, a colored indicator can be used to indicate one or
more degrees of operating conditions, such as and without
limitation, a time based or stress based intermittent use, average
use, and intensive use. Such indications can be based, for example,
on the amount of heat or other operating conditions produced during
one or more uses. Further, multiple colored indicators can be used
that react to varying degrees of attributes to indicate a range of
conditions. Similarly, multiple colored indicators can be used to
indicate multiple operation-related attributes. Examples of
commercially available signaling paints that can be used for this
invention include Temp-Alarm by Tempil, Inc. of South Plainfield,
N.J., USA and Thermo-Paint by Samkwang Corp. of Buchon-City,
Kyonggi-Do, Korea.
[0116] The colored indicators 150 a-f can be formed, affixed,
placed, or otherwise coupled to the RFT support on one or more
surfaces of the support. For example, the colored indicators can be
coupled to the outer periphery 141, to the inner periphery 143, to
side walls 144, or a combination thereof.
[0117] Still further, the style, number, shape, position and angle
with respect to the axis 17 and other datums, depth, width, and/or
placement of the colored indicator on the RFT support can vary and
the examples shown are not intended to be limiting but merely
representative of some of the possible variations. Other variations
can and would exist. The variations can include the above list and
other variations, such as dashes, stripes, geometric patterns, and
so forth.
[0118] The colored indicators can be applied after the molding of
the RFT support in any conventional method. For example and without
limitation, the colored indicator can be applied by gravure
processes, rolling, spinning, flowing, brushing, electrostatic
deposition, dipping, spraying, immersing, powder coating, or other
coating/painting methods. Optionally, the colored indicator can be
cured on or with the RFT support. The colored indicator can also be
applied in the RFT support mold prior to molding, during molding,
or after molding.
[0119] One exemplary method of using the RFT support having a
colored indicator includes the ability to readily select a wheel
rim and match a RFT support suitable to that wheel rim based on the
colored indicator. Naturally, the tire can be matched with the
appropriate rim and/or support, as well.
[0120] The following example is non-limiting and is intended as
merely representative possibilities of aspects of the invention
disclosed herein.
EXAMPLE 1
Production of an RFT Support
[0121] The following is one example of the production of an RFT
support. Naturally, other procedures are available and the example
is intended to include only one of many possibilities. A
pre-fabricated RFT reinforcement was inserted into the inner radius
of an RFT support mold prior to closing the mold. The RFT
reinforcement can be held in position in the mold by pins or other
locating devices. The locating devices can be coupled to the mold
or to the RFT reinforcement. In at least one embodiment, the
locating devices can be an integral part of the RFT reinforcement,
as when tabs or other elements extend from the RFT
reinforcement.
[0122] An RFT support was reaction injected molded (RIM) into this
mold, using a polyurethane-forming, two component, reaction
injection molding formulation based on methylene diphenyl
isocyanate (MDI), polyether polyols, diamine chain extender, a
catalyst and a surfactant. The polyol formulation and the
isocyanate prepolymer were metered into an impingement mixhead
using a metering machine. The reacting liquid passed from the
mixhead into a centered, bottom, axially-oriented sprue. The liquid
was then directed from the sprue into multiple spoke runners in
this example. The spoke runners fed a circumferential runner,
located on a lower inner diameter relative to the RFT support being
molded. The circumferential runner allowed the reacting polymer to
flow over a film gate into a lower portion of the RFT support being
molded. The RFT support mold cavity was oriented substantially
horizontally, that is, with the axis approximately parallel to
gravity during the mold fill. The top of the mold included release
vents for the expulsion of air. The reacting polymer filled the
mold from bottom to top. The mold was held at a temperature of
about 70.degree. C. during introduction of the reacting
polyurethane. The mixhead was closed upon filling the mold, and the
polymer was allowed to cure for 45 seconds. The mold clamp was
opened and the RFT support removed. At least a portion of the RFT
support was painted with a colored paint and indicated at least one
attribute of the RFT support.
[0123] While the foregoing is directed to various embodiments of
the present invention, other and further embodiments can be devised
without departing from the basic scope thereof. For example, the
various methods and embodiments of the invention can be included in
combination with each other to produce variations of the disclosed
methods and embodiments. Discussion of singular elements can
include plural elements and vice-versa. Also, any directions shown
or described such as "top," "bottom," "left," "right," "upper,"
"lower," and other directions and orientations are described herein
for clarity in reference to the figures and are not to be limiting
of the actual device or system or use of the device or system. The
device or system can be used in a number of directions and
orientations. Further, the order of steps can occur in a variety of
sequences unless otherwise specifically limited. The various steps
described herein can be combined with other steps, interlineated
with the stated steps, and/or split into multiple steps.
Additionally, the headings herein are for the convenience of the
reader and are not intended to limit the scope of the
invention.
[0124] Further, any references mentioned in the application for
this patent as well as all references listed in the information
disclosure originally filed with the application are hereby
incorporated by reference in their entirety to the extent such may
be deemed essential to support the enabling of the invention(s).
However, to the extent statements might be considered inconsistent
with the patenting of the invention(s), such statements are
expressly not meant to be considered as made by the Applicants.
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