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(11) |
EP 0 988 158 B9 |
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CORRECTED EUROPEAN PATENT SPECIFICATION |
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Note: Bibliography reflects the latest situation |
| (15) |
Correction information: |
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Corrected version no 1 (W1 B1) |
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Corrections, see
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| (48) |
Corrigendum issued on: |
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27.10.2004 Bulletin 2004/44 |
| (45) |
Mention of the grant of the patent: |
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17.03.2004 Bulletin 2004/12 |
| (22) |
Date of filing: 17.06.1998 |
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| (86) |
International application number: |
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PCT/US1998/012534 |
| (87) |
International publication number: |
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WO 1998/057812 (23.12.1998 Gazette 1998/51) |
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| (54) |
HIGH PERFORMANCE BROAD APPLICATION WHEEL
HOCHLEISTUNGSRAD MIT WEITEM ANWENDUNGSGEBIET
ROUE HAUTES PERFORMANCES A LARGE CHAMP D'APPLICATION
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Designated Contracting States: |
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AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE |
| (30) |
Priority: |
18.06.1997 US 878392
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| (43) |
Date of publication of application: |
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29.03.2000 Bulletin 2000/13 |
| (73) |
Proprietor: Nimble Bicycle Company |
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Austin, TX 78730 (US) |
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| (72) |
Inventors: |
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- LUTTGEHARM, Clint
Wichita, KS 67235 (US)
- NAYER, David
Austin, TX 78730 (US)
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| (74) |
Representative: Eder, Thomas, Dr.-Ing. et al |
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Eder & Schieschke
Patentanwälte,
Elisabethstrasse 34/II 80796 München 80796 München (DE) |
| (56) |
References cited: :
US-A- 4 995 675 US-A- 5 246 275 US-A- 5 540 485
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US-A- 4 995 765 US-A- 5 246 575
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| Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
|
BACKGROUND OF THE INVENTION
[0001] This invention relates to an improved high performance, broad application wheel in
general. In particular, this invention relates to an improved high performance, broad
application wheel for bicycles.
[0002] The search for better performance is endemic in every industry and the industry concerning
the creation of high performance wheels is no exception. In particular, in the bicycle
industry, a parade of innovations has seemingly addressed every aspect of wheel design.
For example, Lipeles, U.S. Patent No. 5,549,360 discloses a minimum weight wheel rim;
Enders, U.S. Patent No. 5,540,485 discloses a composite bicycle wheel having opposing
spokes radiating from a central hub. Various other spoke wheel apparatus and methods
for creating composite spoke wheels are set forth in U.S. Patent Nos. 5,246,275 (corresponding
to the preamble of claim 1), 5,184,874, 5,104,199; 5,061,013; 4,995,675; 4,930,844;
and 4,930,843, for example. Without exception, prior art wheels have two common features.
The first common feature in most prior art wheels is that the rim depth is universally
constant. The second universal feature of most prior art wheels is that the spokes
have a constant, cross-sectional shape.
[0003] A significant portion of the aerodynamic drag of a bicycle and rider in motion is
created by the wheels. This problem has long been recognized and has been the subject
of significant technical investigation and improvement. The drag associated with the
wheel can be divided into two parts: spoke drag and rim drag.
[0004] Traditional tension wire spoke wheel designs optimized for minimum aerodynamic drag
generally have an aerodynamically contoured rim and as few spokes as possible. The
number of spokes is limited by the structure requirements of the tension wheel design.
To further decrease the spoke drag, these spokes are often of a non-circular (elliptical)
constant cross-section with the exception of the circular region retained for attachment
of the spoke ends. Rim drag is minimized by use of an aerodynamically contoured rim
with different designs utilizing depths of from 2 to 5 tire diameters; however, the
depth is universally constant with any given prior art design.
[0005] Modern "aero" wheels utilize a reduced number (3, 4, or 5) of non-tension spokes.
These spokes are capable of sustaining both bending and compression loads in addition
to tensile loads. The larger cross-sections of these spokes are generally an aerodynamic
contour of constant form and proportion. Some wheels have been fabricated using varying
proportions of a constant formed spoke from the hub to the rim. The rim sections incorporated
in these rims are of constant aerodynamic cross-section. While different designs utilize
depths of from 2 to 5 tire diameters, the depth is universally constant within any
given design.
[0006] The designs of all of these wheels attempt to obtain maximum performance for a given
rider's capabilities. Directly measurable parameters of this performance include apparent
and rotational drag, cross wind drag, rotational moment of inertia, and mass. Less
tangible performance parameters of any given design are the comfort and feel of the
wheel.
[0007] The inventors have determined that the local velocity profiles for a rotating wheel
contain a significant region of flow reversal relative to the intended flow direction
over the spokes. Additionally, the inventors determined that the sharp, trailing edge
of conventional prior art designs produces separation and increased drag in this region
of reverse flow. These effects are most pronounced in the presence of cross winds.
[0008] A drawback to the wheels known in the art is that solid disc wheels with no spokes
are aerodynamically and structurally sound, but offer unacceptable wind resistance
when cross wind exists. In circumstances where cross wind does exist, the wheel of
choice, therefore, is a spoked wheel. Prior art wheels with spokes, however, have
not provided a spoked wheel that is aerodynamically efficient in a head wind as well
as a cross wind. Thus, there is a need in the art for providing a high performance,
broad application wheel that performs as equally well in heads winds as in cross winds.
It, therefore, is an object of this invention to provide an improved high performance,
broad application wheel for providing optimum performance in any wind condition, including
head winds and cross winds.
SHORT STATEMENT OF THE INVENTION
[0009] Accordingly, the wheel of the present invention includes the features of claim 1.
The depth of the rim varies circumferentially and which includes at least one spoke
with a first end connected to the rim and a second end connected to a wheel hub wherein
the cross-section of the spoke varies from the first end to the second end. The rim
depth varies circumferentially so that the depth is greater between the spokes and
less at the spoke. The spoke cross-section is symmetric at the second end and asymmetrical
at the first end. In a preferred embodiment, the symmetrical second end is in the
shape of an ellipse. The asymmetrical first end contains this same elliptical form
as a leading edge while the basic geometric form is a standard airfoil modified to
include an elliptical sector trailing edge. This elliptical trailing edge sector of
the first end is significantly smaller in dimension than the ellipses of the symmetric
second end and the leading edge of the first end.
[0010] The spokes have a variable cross-section so that the first end is symmetric only
about a rolling plane of the wheel and the second end is symmetric about a radial
plane and the rolling plane of the wheel. Additionally, in a preferred embodiment,
the rim varies circumferentially so that the area moment of inertia between the spokes
is greater than the area moment of inertia at the first end of the spokes. Further,
in a preferred embodiment, the rim and/or spoke(s) is a hollow structure manufactured
from multiple nested, tubular braids.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Other objects, features and advantages of the present invention will become more
fully apparent from the following detailed description of the preferred embodiment,
the appended claims and the accompanying drawings in which:
FIGURE 1 is a plan view of a preferred embodiment of the high performance, broad application
wheel of the present invention;
FIGURE 2 is a perspective view of the invention in FIGURE 1;
FIGURE 3 is a side view illustrating the varying circumference of the spokes of the
invention;
FIGURE 4 is a cross-sectional view of prior art spoke shape;
FIGURE 5 is a cross-sectional view of the spoke shape of the invention;
FIGURE 6 is a cross-sectional view of a preferred embodiment of the hollow rim of
the invention in FIGURE 1 with a brake box;
FIGURE 7 is a cross-sectional view of a preferred embodiment of the rim of the invention
in FIGURE 1 with a portion of the brake box cut away as shown in dotted lines for
providing a clincher style rim; and
FIGURE 8 is a cross-sectional view of the hollow spoke of the invention in FIGURE
1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0012] The preferred embodiment of the present invention is illustrated by way of example
in Figures 1-8. With specific reference to Figures 1 and 2, a high performance, broad
application wheel 10 of the present invention, includes rim 12 and spokes 14. Spokes
14 have a first end 16 and a second end 18. First end 16 is connected to rim 12 and
second end 18 is connected to wheel hub 20 of any known design and not discussed or
disclosed further hereafter. As can be most clearly seen in Figure 1, rim 12 varies
in depth circumferentially. As illustrated in Figure 1, the depth of rim 12 at point
22 is significantly greater than the depth of the rim 12 at points 24 where spokes
14 first ends 16 connect with rim 12.
[0013] Referring to Figure 3, spokes 14 are illustrated so as to show that spokes 14 are
symmetrical in cross-section at point 26, (wheel hub 20) and asymmetrical at point
28, where first end 16 attaches to rim 12. It should be noted that most prior art
wheels also require and include a spoke rim flare and/or fillet at point 28, so that
a large area of increased wind resistance is present at point 28. To the contrary,
spokes 14 have no such increased area and, therefore, normal wind resistance is reduced
by spokes 14 at point 28.
[0014] Referring to Figure 4, a cross-sectional illustration of a prior art spoke is shown.
Prior art spokes have a constant cross-sectional geometric form typically of an airfoil
shape. These airfoil shapes generally consist of an elliptical leading edge 30, a
tapered after body 31, and a sharp trailing edge 32. The inventors have determined
that sharp trailing edge 32 of prior art spokes rather than helping actually produces
separation and dramatically increases drag in the region of reverse flow. The inventors
have determined that this region of reverse flow appears primarily between the wheel
hub and the point of ground contact for the wheel.
[0015] Referring to Figure 5, Applicant's invention includes, in a preferred embodiment,
elliptical leading edge 30 in combination with smaller elliptical trailing edge 34.
Referring to Figure 3, elliptical leading edge 30 is generally constant in shape from
second end 18 to first end 16. On the other hand, smaller elliptical trailing edge
34 has the same dimension as elliptical leading edge 30 at point 26 of wheel hub 20,
but has a much smaller elliptical sector at first end 16, reducing across the length
of spoke 14 from point 26 to point 28. While an elliptical shape is preferred, it
is only one of many suitable shapes such as near elliptical, ogive, parabolic, exponential
spandrel, quadratic, cubic or other polynomial, and the like.
[0016] It should be clear from reference to Figures 1, 2, 3, and 5 that spokes 14 have a
variable cross section wherein the first end 16 is symmetrical only about the rolling
plane of high performance, broad application wheel 10. On the other hand, second end
18 of spoke 14 is symmetrical about both the rolling plane and the radial plane of
high performance, broad application wheel 10. It should be understood that near symmetry
and nearly constant shapes are included in this invention so long as the cross-section
varies as required.
[0017] Additionally, the inventors have determined that by way of the variance in the circumference
of rim 12, rim 12 varies circumferentially so that the area moment of inertia between
spokes 14 is greater than the area moment of inertia at the first end 16 of spokes
14. In a preferred embodiment, as shown in Figures 1 and 2, three spokes 14 are connected
with wheel hub 20 and rim 12.
[0018] By way of the present invention, therefore, a high performance, broad application
wheel 10 maximizes aerodynamic performance. Additionally, the inventors have determined
that wheel 10 levels ride feel, lessens road shock, and saves mass. In fact, contrary
to prior art wheels which maximize performance primarily in one category, the inventors
have determined that high performance, broad application wheel 10 is best or near
best in all varieties of conditions, i.e. calm, head wind and cross wind.
[0019] In a preferred embodiment, the rim 12 is a hollow structure manufactured from multiple
nested tubular braids. As shown in the cross sectional diagram of Figure 6, the innermost
braid 40 forms a box structure 52 which carries the compressive loads applied by a
brake caliper (not shown). The braid architecture of this braid is selected to provide
an open braid angle suitable for these loads. This "open" braid angle is defined as
a braid configuration wherein the braid diameter is at or near the maximum possible
which orients the yarns with the circumference of the braid. An optional second inner
braid 41 is added for applications where the rim 12 is to be used with tensioned wire
spokes. An outer braid 42 forms the outer layer of the rim 12. Braid 42 is of a braid
architecture to provide a closed braid angle suitable for the combined bending and
torsional loads present in rim 12. This "closed" braid angle is defined as a braid
configuration wherein the braid diameter is at or near the minimum possible which
aligns the yarns with the longitudinal axis of the braid. These braids are reinforced
with circumferential charges of unidirectional fiber 43 to enhance flexural stiffness
and strength. In a preferred embodiment, these charges are located at the extreme
inner diameter 44 and extreme outer diameter 45. For clincher style rims, the position
of this outer unidirectional charge 43 must move inward as shown in Figure 7. A portion
of the brake box 52 braid 40 and the outer braid 42 are then removed by machine cut
51 (shown in dotted lines) to create the beads 49 of the clincher rim. Additional
filler material 50 may be used in this region to prevent severing of structural plies
40 and 42.
[0020] In a preferred embodiment, the spoke 14 is a hollow structure manufactured from single
or multiple tubular braids as shown in Figure 8. The outer spoke braid 46 is of an
architecture to provide a closed braid angle suitable for the combined bending and
torsional loads present in spoke 14. The outer braid 46 may be supplemented by optional
internal braids 47 to provide a multiple cell, torsion resistant structure. Reinforcement
of unidirectional fiber charges 48 can be added on the sides of spoke 14 to enhance
lateral stiffness and strength. It should be understood that for either the rim 12
or the spoke(s) 14, the individual braids 40, 41, 42 each possess an independent braid
angle, from open to closed, consistent with the intended structural function of the
braid within the rim 12 and/or spoke(s) 14.
[0021] In a preferred embodiment, the rim 12 and/or spoke 14 is comprised of an all composite
carbon graphite material, but any known materials that are sufficiently strong and
resilient so as to provide optimal combinations of light weight and minimal rotational
inertia, while providing the required strength and stiffness are suitable.
[0022] While the wheel of the present invention has been disclosed in connection primarily
with bicycles, it should be appreciated that the high performance, broad application
wheel can be used with any wheels subjected to air conditions that range from calm
to cross wind situations. The present invention provides best or near best performance
in all types of situations, thereby eliminating the need for carrying an inventory
of wheels designed for peak performance in only one category.
[0023] While the present invention has been disclosed in connection with the preferred embodiment
thereof, it should be understood that there may be other embodiments which fall within
the scope of the invention as defined by the following claims.
1. A wheel (10) with a rim (12) comprising at least one spoke (14) with a first end (16)
connected to said rim (12) and a second end (18) connected to a wheel hub (20) wherein
the cross-section of said spoke (14) varies from said first end (16) to said second
end (18) and
wherein said spoke cross-section being asymmetric about a radial plane being perpendicular
to the rolling plane of said wheel (10) at said first end (16)
characterized in that
said spoke cross-section varies in geometric form from said first end (16) to said
second end (18) and
in that said spoke cross-section is near symmetric about said radial plane at said second
end (18).
2. The wheel of Claim 1, wherein said spoke (14) further comprises at least one hollow
spoke of fibrous, composite construction from one or more tubular braids (46, 47).
3. The wheel of Claim 2 wherein said individual braids (46, 47) each possess an independent
braid angle consistent with the intended structural function of the braid (46, 47)
within said rim (12).
4. The wheel of Claim 3 wherein unidirectional fiber (43), oriented in a radial direction,
is positioned at or near extreme sides of the said spoke (14) section.
5. The wheel of Claim 1 wherein said symmetrical second end (18) is in the shape of an
ellipse.
6. The wheel of Claim 5 wherein said spoke (14) has a leading edge (30) elliptical sector
that is constant from said first end (16) to said second end (18) and a trailing edge
(34) elliptical sector that is the same in dimension as said leading edge (30) at
said second end (18) and thereafter decreases in dimension from said second end (18)
to said first end (16).
7. The wheel of Claim 1 wherein said spoke (14) has a variable cross-section so that
said first end (16) is symmetric only about a rolling plane of said wheel (10) and
said second end (18) is symmetric about both a radial plane and said rolling plane
of said wheel (10).
8. The wheel of Claim 5 wherein said leading end trailing edge shapes are chosen from
a group of shapes including near elliptical, ogive, parabolic, exponential spandrel,
quadratic and cubic.
9. The wheel of claim 1 applicable as a high performance, broad application bicycle wheel
comprising at least three spokes (14), wherein the depth of said rim (12) varies circumferentially.
10. The wheel of Claim 9 wherein said rim depth varies circumferentially so that the depth
is greater between said spokes (14) and less at said spokes (14).
11. The wheel of Claim 9 wherein said spokes (14) have a variable cross-section so that
said first end (16) is symmetric only about the rolling plane of said wheel (10) and
said second end (18) is symmetric about both the radial plane and said rolling plane
of said wheel (10).
12. The wheel of Claim 9 wherein said rim (12) varies circumferentially so that the area
moment of inertia between said spokes (14) is greater than the area moment of inertia
at said first end (16) of said spokes (14).
13. The wheel of Claim 9 wherein said spoke cross-section is asymmetric about a radial
plane at said first end (16) and is symmetric or near symmetric about a radial plane
at said second end (18).
14. The wheel of Claim 11 wherein said spoke cross-section varies in both geometrical
form and dimension from said first end (16) to said second end (18).
15. The wheel of Claim 14 wherein the said spoke cross-section at said second end (18)
is an ellipse.
16. The wheel of Claim 15 wherein said spoke cross-section at said first end (16) is a
standard airfoil altered by the substitution of an elliptical trailing edge.
17. The wheel of Claim 16 wherein said rim (12) further comprises a hollow rim of fibrous,
composite construction from multiple, nested tubular braids.
18. The wheel of Claim 17 wherein said individual braids each (40, 41, 42) possess an
independent braid angle consistent with the intended structural function of the braid
(40, 41, 42) within said rim (12).
19. The wheel of claim 18 wherein unidirectional fiber (43), oriented in a circumferential
direction, is positioned at or near extreme portions of the rim section.
1. Rad (10) mit einer Felge (12), die mindestens eine Speiche (14) aufweist, deren erstes
Ende (16) mit der Felge (12) verbunden ist und deren zweites Ende (18) mit einer Radnabe
(20) verbunden ist, wobei der Querschnitt der Speiche (14) vom ersten Ende (16) bis
zum zweiten Ende (18) variiert und
wobei der Querschnitt der Speiche am ersten Ende (16) asymmetrisch um eine radiale
Ebene ist, die senkrecht zur Rollebene des Rads (10) ist,
dadurch gekennzeichnet, dass
der Querschnitt der Speiche in seiner geometrischen Form vom ersten Ende (16) bis
zum zweiten Ende (18) variiert und
dass der Querschnitt der Speiche am zweiten Ende (18) um die radiale Ebene nahezu
symmetrisch ist.
2. Rad nach Anspruch 1, bei dem die Speiche (14) außerdem aus mindestens einer hohlen
Speiche in Form einer Faserverbundwerkstoffkonstruktion aus einem oder mehreren röhrenförmigen
Geflechten (46, 47) besteht.
3. Rad nach Anspruch 2, bei dem die einzelnen Geflechte (46, 47) jeweils einen unabhängigen
Geflechtwinkel besitzen, der mit der vorgesehenen strukturellen Funktion des Geflechts
(46, 47) innerhalb der Felge (12) übereinstimmt.
4. Rad nach Anspruch 3, bei dem unidirektionale Fasern (43), die in einer radialen Richtung
ausgerichtet sind, an oder nahe den äußersten Seiten des Querschnitts der Speiche
(14) positioniert sind.
5. Rad nach Anspruch 1, bei dem das symmetrische zweite Ende (18) in Form einer Ellipse
vorliegt.
6. Rad nach Anspruch 5, bei dem die Speiche (14) einen elliptischen Vorderkantenabschnitt
(30) aufweist, der vom ersten Ende (16) bis zum zweiten Ende (18) konstant ist, und
einen elliptischen Hinterkantenabschnitt (34), der in seiner Abmessung der Vorderkante
(30) am zweiten Ende (18) entspricht und dann in seiner Abmessung vom zweiten Ende
(18) zum ersten Ende (16) abnimmt.
7. Rad nach Anspruch 1, bei dem die Speiche (14) einen variablen Querschnitt aufweist,
so dass das erste Ende (16) nur um eine Rollebene des Rads (10) symmetrisch ist und
das zweite Ende (18) sowohl um eine radiale Ebene als auch um die Rollebene des Rads
(10) symmetrisch ist.
8. Rad nach Anspruch 5, bei dem die Formen der Vorder- und der Hinterkante aus einer
Gruppe von Formen ausgewählt werden, zu welchen eine nahezu elliptische, eine spitzbogenartige,
eine parabolische, die Form einer exponentiellen Spandrille, eine quadratische und
eine kubische Form zählen.
9. Rad nach Anspruch 1, anwendbar als Hochleistungsrad für ein Fahrrad mit breitem Anwendungsgebiet,
das mindestens drei Speichen (14) aufweist, wobei die Tiefe der Felge (12) entlang
dem Umfang variiert.
10. Rad nach Anspruch 9, bei dem die Tiefe der Felge entlang dem Umfang so variiert, dass
die Tiefe zwischen den Speichen (14) größer ist und an den Speichen (14) geringer
ist.
11. Rad nach Anspruch 9, bei dem die Speichen (14) einen variablen Querschnitt haben,
so dass das erste Ende (16) nur um die Rollebene des Rads (10) symmetrisch ist und
das zweite Ende (18) sowohl um die radiale Ebene als auch um die Rollebene des Rads
(10) symmetrisch ist.
12. Rad nach Anspruch 9, bei dem die Felge (12) entlang dem Umfang so variiert, dass das
Bereichs-Trägheitsmoment zwischen den Speichen (14) größer ist als das Bereichs-Trägheitsmoment
am ersten Ende (16) der Speichen (14).
13. Rad nach Anspruch 9, bei dem der Querschnitt der Speiche um eine radiale Ebene am
ersten Ende (16) asymmetrisch ist und um eine radiale Ebene am zweiten Ende (18) symmetrisch
oder nahezu symmetrisch ist.
14. Rad nach Anspruch 11, bei dem der Querschnitt der Speiche sowohl in der geometrischen
Form als auch in der Abmessung vom ersten Ende (16) bis zum zweiten Ende (18) variiert.
15. Rad nach Anspruch 14, bei dem der Querschnitt der Speiche am zweiten Ende (18) eine
Ellipse ist.
16. Rad nach Anspruch 15, bei dem der Querschnitt der Speiche am ersten Ende (16) der
einer Standard-Tragfläche ist, abgeändert durch den Austausch einer elliptischen Hinterkante.
17. Rad nach Anspruch 16, bei dem die Felge (12) außerdem aus einer hohlen Felge aus einer
Faserverbundwerkstoffkonstruktion aus mehreren, ineinandergesetzten röhrenförmigen
Geflechten besteht.
18. Rad nach Anspruch 17, bei dem die einzelnen Geflechte jeweils (40, 41, 42) einen unabhängigen
Geflechtwinkel besitzen, der mit der vorgesehenen strukturellen Funktion des Geflechts
(40, 41, 42) innerhalb der Felge (12) übereinstimmt.
19. Rad nach Anspruch 18, bei dem unidirektionale Fasern (43), die in einer Umfangsrichtung
ausgerichtet sind, an oder nahe den äußersten Bereichen des Querschnitts der Felge
positioniert sind.
1. Roue (10) munie d'une jante (12) comportant au moins un rayon (14) ayant une première
extrémité (16) connectée à ladite jante (12) et une seconde extrémité (18) connectée
à un moyeu de roue (20), la coupe transversale dudit rayon (14) variant à partir de
ladite première extrémité (16) vers ladite seconde extrémité (18), et
ladite coupe transversale du rayon étant asymétrique sur un plan radial perpendiculaire
au plan de roulement de ladite roue (10) au niveau de ladite première extrémité (16),
caractérisée en ce que
ladite coupe transversale du rayon a une forme géométrique qui varie à partir de
ladite première extrémité (16) vers ladite seconde extrémité (18), et
en ce que ladite coupe transversale du rayon est presque symétrique par rapport audit plan
radial au niveau de ladite seconde extrémité (18).
2. Roue selon la revendication 1, dans laquelle ledit rayon (14) comporte de plus au
moins un rayon creux constitué d'une construction composite fibreuse à partir d'une
ou plusieurs tresses tubulaires (46, 47).
3. Roue selon la revendication 2, dans laquelle lesdites tresses individuelles (46, 47)
possèdent chacune un angle de tresse indépendant cohérent avec la fonction structurale
prévue de la tresse (46, 47) dans ladite jante (12).
4. Roue selon la revendication 3, dans laquelle une fibre unidirectionnelle (43), orientée
dans une direction radiale, est positionnée au niveau ou à proximité des côtés extrêmes
de ladite coupe du rayon (14).
5. Roue selon la revendication 1, dans laquelle ladite seconde extrémité symétrique (18)
a la forme d'une ellipse.
6. Roue selon la revendication 5, dans laquelle ledit rayon (14) comporte un secteur
elliptique de bord d'attaque (30) qui est constant à partir de ladite première extrémité
(16) vers ladite seconde extrémité (18), et un secteur elliptique de bord de queue
(34) qui a la même dimension que ledit bord d'attaque (30) au niveau de ladite seconde
extrémité (18), et dont la dimension diminue ensuite à partir de ladite seconde extrémité
(18) vers ladite première extrémité (16).
7. Roue selon la revendication 1, dans laquelle ledit rayon (14) a une coupe transversale
variable, de sorte que ladite première extrémité (16) est symétrique uniquement par
rapport à un plan de roulement de ladite roue (10), et ladite seconde extrémité (18)
est symétrique à la fois par rapport à un plan radial et audit plan de roulement de
ladite roue (10).
8. Roue selon la revendication 5, dans laquelle lesdites formes de bord d'attaque et
de queue sont sélectionnées parmi un groupe de formes comportant des formes pratiquement
elliptiques, en ogive, parabolique, en tympan exponentiel, quadratique et cubique.
9. Roue selon la revendication 1, pouvant être appliquée en tant que roue de bicyclette
à application large et haute performance, comportant au moins trois rayons (14), dans
laquelle la profondeur de ladite jante (12) varie circonférentiellement.
10. Roue selon la revendication 9, dans laquelle ladite profondeur de jante varie circonférentiellement,
de sorte que la profondeur est supérieure entre lesdits rayons (14), et inférieure
au niveau desdits rayons (14).
11. Roue selon la revendication 9, dans laquelle lesdits rayons (14) ont une coupe transversale
variable, de sorte que ladite première extrémité (16) est symétrique uniquement par
rapport au plan de roulement de ladite roue (10), et ladite seconde extrémité (18)
est symétrique à la fois par rapport au plan radial et audit plan de roulement de
ladite roue (10).
12. Roue selon la revendication 9, dans laquelle ladite jante (12) varie circonférentiellement,
de sorte que l'aire de moment d'inertie entre lesdits rayons (14) est supérieure à
l'aire de moment d'inertie au niveau de ladite première extrémité (16) desdits rayons
(14).
13. Roue selon la revendication 9, dans laquelle ladite coupe transversale du rayon est
asymétrique par rapport à un plan radial au niveau de ladite première extrémité (16),
et est symétrique ou presque symétrique par rapport à un plan radial au niveau de
ladite seconde extrémité (18).
14. Roue selon la revendication 11, dans laquelle ladite coupe transversale du rayon varie
à la fois en dimension et en forme géométrique à partir de ladite première extrémité
(16) vers ladite seconde extrémité (18).
15. Roue selon la revendication 14, dans laquelle ladite coupe transversale du rayon au
niveau de ladite seconde extrémité (18) est une ellipse.
16. Roue selon la revendication 15, dans laquelle ladite coupe transversale du rayon au
niveau de ladite première extrémité (16) est une aile standard modifiée par le remplacement
d'un bord de queue elliptique.
17. Roue selon la revendication 16, dans laquelle ladite jante (12) comporte de plus une
jante creuse constituée d'une construction composite fibreuse provenant de multiples
tresses tubulaires emboîtées.
18. Roue selon la revendication 17, dans laquelle lesdites tresses individuelles (40,
41, 42) possèdent chacune un angle de tresse indépendant cohérent avec la fonction
structurale prévue de la tresse (40, 41, 42) dans ladite jante (12).
19. Roue selon la revendication 18, dans laquelle une fibre unidirectionnelle (43), orientée
dans une direction circonférentielle, est positionnée au niveau ou à proximité des
parties extrêmes de la coupe de la jante.