U.S. patent application number 17/730810 was filed with the patent office on 2022-08-18 for bicycle handlebar having different directional stiffnesses.
The applicant listed for this patent is D3 Innovation Inc.. Invention is credited to Jonathan Staples.
Application Number | 20220258828 17/730810 |
Document ID | / |
Family ID | 1000006303175 |
Filed Date | 2022-08-18 |
United States Patent
Application |
20220258828 |
Kind Code |
A1 |
Staples; Jonathan |
August 18, 2022 |
BICYCLE HANDLEBAR HAVING DIFFERENT DIRECTIONAL STIFFNESSES
Abstract
An elongate, tubular handlebar can include a laterally extending
central mounting portion, a tubular left body section extending
laterally from one side of the mounting portion a tubular right
body section extending laterally from the other side of the
mounting portion. The right body section may have an elongate,
tubular right control portion extending laterally from an inboard
end to an outboard end and configured to support a generally
laterally extending grip and a right transition portion having a
non-circular, transition cross-sectional shape at a first location
defining a first width measured in a first direction and a second
width that is greater than the first width and is measured in a
second direction. Whereby right body section has a first stiffness
in the first direction and a second stiffness that is greater than
the first stiffness in the second direction.
Inventors: |
Staples; Jonathan;
(Squamish, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
D3 Innovation Inc. |
Squamish |
|
CA |
|
|
Family ID: |
1000006303175 |
Appl. No.: |
17/730810 |
Filed: |
April 27, 2022 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
16823230 |
Mar 18, 2020 |
11352093 |
|
|
17730810 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B62K 21/145 20130101;
B62K 21/26 20130101 |
International
Class: |
B62K 21/14 20060101
B62K021/14; B62K 21/26 20060101 B62K021/26 |
Claims
1. An elongate, tubular handlebar connectable to a steerer tube of
a bicycle, the handlebar comprising: a) a laterally extending
central mounting portion configured to be connected to the steerer
tube of a bicycle and extending along a mounting axis; b) a tubular
left body section extending laterally from one side of the mounting
portion and comprising a left control portion configured to support
a grip and a left transition portion extending laterally between
the left control portion and the mounting portion; c) a tubular
right body section extending laterally from the other side of the
mounting portion and comprising: i. an elongate, tubular right
control portion extending laterally from an inboard end to an
outboard end and configured to support a generally laterally
extending grip; and ii. a right transition portion extending
laterally between the inboard end of the right control portion and
the mounting portion and having a non-circular, transition
cross-sectional shape at a first location defining a first width
measured in a first direction extending in a plane that is
orthogonal to the mounting axis and a second width that is greater
than the first width and is measured in a second direction that is
measured in the plane and that is at an angle relative to the first
direction, wherein when the handlebar is connected to the steerer
tube forces exerted in the second direction exert steering forces
on the steering tube; whereby when an input force is applied to the
right control portion in the first direction the right body section
has a first stiffness and when the input force is applied to the
right control portion in the second direction the right body
section has a second stiffness that is greater than the first
stiffness.
2. The handlebar of claim 1, wherein the mounting portion has a
substantially circular cross-sectional shape having a mounting
diameter and the right control portion has a substantially circular
cross-sectional shape having a control diameter that is less than
the mounting diameter, and wherein the first width and the second
width are each greater than the control diameter and less than the
mounting diameter.
3. The handlebar of claim 2, wherein the right transition portion
further comprises a second non-circular, transition cross-sectional
shape at a second location that is laterally spaced apart from the
first location and that defines a third width measured in the first
direction that is less than the first width and a fourth width
measured in the second direction that is less than the third width
and the second width.
4. The handlebar of claim 1, wherein the right transition portion
has an inboard end adjacent the mounting portion and an outboard
end adjacent the right control portion and wherein the first
location is disposed substantially equally between the inboard end
and the outboard end
5. The handlebar of claim 4, wherein the right transition zone
comprises a first wall thickness at the inboard end and greater
second wall thickness at the outboard end.
6. The handlebar of claim 4, wherein the right transition portion
has a substantially circular cross-sectional shape at the inboard
end and at the outboard end.
7. The handlebar of claim 1, wherein the second direction is
substantially orthogonal to the first direction.
8. The handlebar of claim 1, wherein the right transition portion
is configured so that when the mounting portion is connected to the
steerer tube of a bicycle the first direction is oriented within
about 45 degrees of an axis of rotation of the steerer tube.
9. The handlebar of claim 1, wherein the right transition portion
is configured so that when the mounting portion is connected to the
steerer tube of a bicycle the first direction is oriented within
about 30 degrees of a vertical plane.
10. The handlebar of claim 1, wherein the right transition portion
is configured so that when the mounting portion is connected to the
steerer tube of a bicycle the second direction is within about 45
degrees of a horizontal plane.
11. The handlebar of claim 1, wherein the second stiffness is
between about 110% and 150% of the first stiffness.
12. The handlebar of claim 1, wherein the first stiffness is
between about 5.5 and about 7.5 (kg/mm) and the second stiffness is
between about 8 and about 10 (kg/mm).
13. The handlebar of claim 1, wherein the first width is between
about 15mm and about 30mm and wherein the second width is between
about 25mm and about 35mm.
14. The handlebar of claim 1, wherein the first width is between
about 60% and about 90% of the second width.
15. The handlebar of claim 1, wherein the right transition portion
has a substantially elliptical transition cross-sectional shape at
the first location and has an eccentricity calculated as 1 - (
first width second width ) 2 ##EQU00006## that is between about 0.5
and about 0.8 at the first location.
16. The handlebar of claim 1, wherein the left transition portion
comprises a third non-circular, transition cross-sectional shape at
a third location defining a fifth maximum width measured in the
first direction and a sixth width that is greater than the fifth
width and is measured in the second direction; whereby when an
input force is applied to the left control portion in the first
direction the left body section has a third stiffness and when the
input force is applied to the left control portion in the second
direction the left body section has a fourth stiffness that is
greater than the third stiffness.
17. The handlebar of claim 1, wherein a distance between an
outboard end of the left control portion and the outboard end of
the right control portion in the lateral transverse direction
defines a handlebar length, and wherein the handlebar length is
between about 700 mm and about 900 mm.
18. The handlebar of claim 1, wherein the right transition portion
has a transition length in the transverse direction that is between
about 15% and about 25% of the handlebar length.
19. The handlebar of claim 18, wherein the right control portion
has a control length in the transverse direction that is greater
than the transition length.
20. The handlebar of claim 1, wherein the right control portion
extends along a right control axis that intersects the mounting
axis at a sweep angle that is between about 0 and about 15 degrees.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation of U.S. patent
application Ser. No. 16/823,230, filed Mar. 18, 2020 and entitled
BICYCLE HANDLEBAR HAVING DIFFERENT DIRECTIONAL STIFFNESSES, the
entirety of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] In one of its aspects, the present disclosure relates to a
handlebar for a bicycle, and in particular a handlebar configured
to have different flexural rigidities (e.g. bending stiffnesses)
when subjected to a given force in different directions.
INTRODUCTION
[0003] U.S. Pat. No. 6,983,949 discloses a bicycle headset
structure that is provided to aid in concealment of wiring from
components mounted in the handlebar area to components mounted on
the rest of the bicycle. The bicycle headset structure basically
comprises a handlebar attachment member and a tubular spacer
member. The handlebar attachment member has wiring passage extends
between the handlebar mounting portion and the steerer tube
attachment portion. The tubular spacer member has a wiring channel
extending between first and second ends of the tubular spacer
member and an axial passageway extending axially between the upper
and lower end openings of the tubular spacer member. The axial
passageway is dimensioned to receive the bicycle steerer tube. The
wiring channel is arranged to communicate with the wiring passage
of handlebar attachment member when the handlebar attachment member
and the tubular spacer member are attached to the bicycle steerer
tube.
[0004] US patent publication no. 2006/0169094 discloses a handlebar
that includes a handlebar main body, a pair of support walls, a
first slit, and a brake lever. The handlebar main body is hollow
and is mounted to the handlebar stem. The hollow interior of the
handlebar main body is formed with the support walls that extend
along at least a portion of the length of the interior of the
handlebar main body. The brake lever has a lever body and a brake
cable attachment portion. The lever body is pivotally supported by
the support walls proximate the first slit. The lever body includes
a brake operating portion that extends away from the handlebar main
body and a pivot support portion that is pivotally mounted to the
support walls.
[0005] U.S. Pat. No. 4,750,754 discloses handlebars that include a
crosspiece connected to a bicycle steerer tube, and first handles
are connected to the crosspiece. Novel second handles extend
forwardly from the crosspiece; these second handles are located so
that, when they are grasped by a rider, the rider's forearms are
located to be supported by the handlebars at positions over the
crosspiece. The second handles are located relatively close
together to encourage the rider to adopt a riding position in which
the frontal area of the rider's silhouette is minimized, and in
which the rider's elbows are located ahead of the rider's
lungs.
SUMMARY
[0006] In accordance with one embodiments of the teachings
described herein an elongate, tubular handlebar may include a
laterally extending central mounting portion configured to be
connected to the steerer tube of a bicycle and extending along a
control axis. A tubular left body section may extend laterally from
one side of the mounting portion and may include a left control
portion configured to support a grip and a left transition portion
extending laterally between the left control portion and the
mounting portion. A tubular right body section may extend laterally
from the other side of the mounting portion and may include an
elongate, tubular right control portion extending laterally from an
inboard end to an outboard end and configured to support a
generally laterally extending grip. A right transition portion may
extend laterally between the inboard end of the right control
portion and the mounting portion and may have a non-circular,
transition cross-sectional shape at a first location defining a
first width measured in a first direction extending in a plane that
is orthogonal to the mounting axis and a second width that is
greater than the first width and is measured in a second direction
that is measured in the plane and that is at an angle relative to
the first direction. When an input force is applied to the right
control portion in the first direction the right body section may
have a first stiffness and when the input force is applied to the
right control portion in the second direction the right body
section may have a second stiffness that is greater than the first
stiffness.
[0007] The mounting portion may have a substantially circular
cross-sectional shape with a mounting diameter and the right
control portion may have a substantially circular cross-sectional
shape with a control diameter that is less than the mounting
diameter. The first width and the second width may each be greater
than the control diameter and less than the mounting diameter.
[0008] The right transition portion further may include a second
non-circular, transition cross-sectional shape at a second location
that is laterally spaced apart from the first location and that
defines a third width measured in the first direction that is less
than the first width and a fourth width measured in the second
direction that is less than the third width and the second
width.
[0009] The third width and the second width may each be greater
than the control diameter and less than the mounting diameter.
[0010] The right transition portion may have an inboard end
adjacent the mounting portion and an outboard end adjacent the
right control portion and wherein the first location is disposed
substantially equally between the inboard end and the outboard
end.
[0011] The right transition zone may have a first wall thickness at
the inboard end and greater second wall thickness at the outboard
end.
[0012] The right transition portion may have a substantially
circular cross-sectional shape at the inboard end and at the
outboard end.
[0013] The second direction may be substantially orthogonal to the
first direction.
[0014] The right transition portion may be configured so that when
the mounting portion is connected to the steerer tube of a bicycle
the first direction is oriented within about 45 degrees of an axis
of rotation of the steerer tube.
[0015] The right transition portion may be configured so that when
the mounting portion is connected to the steerer tube of a bicycle
the first direction is oriented within about 30 degrees of a
vertical plane.
[0016] The right transition portion may be configured so that when
the mounting portion is connected to the steerer tube of a bicycle
the second direction is within about 45 degrees of a horizontal
plane.
[0017] The right transition portion may be configured so that when
the mounting portion is connected to the steerer tube of a bicycle
the second direction is within about 10 degrees of a horizontal
plane
[0018] The second stiffness may be between about 110% and 150% of
the first stiffness.
[0019] The first stiffness may be between about 5.5 and about 7.5
(kg/mm) and the second stiffness may be between about 8 and about
10 (kg/mm).
[0020] The first width may be between about 15 mm and about 30
mm.
[0021] The second width may be between about 25 mm and about 35
mm.
[0022] The first width may be between about 60% and about 90% of
the second width.
[0023] The right transition portion may have a substantially
elliptical transition cross-sectional shape at the first location
and has an eccentricity calculated as
1 - ( first width second width ) 2 ##EQU00001##
that is between about 0.5 and about 0.8 at the first location.
[0024] The right transition portion may be formed from at least one
of a composite material and aluminium.
[0025] The handlebar may be of integral, one-piece
construction.
[0026] The left transition portion may have a third non-circular,
transition cross-sectional shape at a third location defining a
fifth maximum width measured in the first direction and a sixth
width that is less than the fifth width and is measured in the
second direction. When an input force is applied to the left
control portion in the first direction the left body section may
have a third stiffness and when the input force is applied to the
left control portion in the second direction the left body section
may have a fourth stiffness that is greater than the third
stiffness.
[0027] A distance between outboard ends of the left and right
outboard portions in the lateral transverse direction may define a
handlebar length that may be between about 700 mm and about 900
mm.
[0028] The right transition portion may have a transition length in
the transverse direction that is between about 15% and about 25% of
the handlebar width.
[0029] The cross-sectional shape of the right transition portion
may vary along its transition length.
[0030] The right control portion may have a control length in the
transverse direction that is greater than the transition
length.
[0031] The right control portion may extend along a right control
axis that intersects the control axis at a sweep angle that is
between about 0 and about 15 degrees.
[0032] Other advantages of the invention will become apparent to
those of skill in the art upon reviewing the present
specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Embodiments of the present invention will be described with
reference to the accompanying drawings, wherein like reference
numerals denote like parts, and in which:
[0034] FIG. 1 is back view of one example of a handlebar;
[0035] FIG. 2 is a top view of the handlebar of FIG. 1;
[0036] FIG. 3 is a cross-sectional view taken along line 3-3;
[0037] FIG. 4 is a cross-sectional view taken along line 4-4;
[0038] FIG. 5 is a cross-sectional view taken along line 5-5;
[0039] FIG. 6 is a cross-sectional view taken along line 6-6;
[0040] FIG. 7 is a cross-sectional view taken along line 7-7;
[0041] FIG. 8 is a cross-sectional view taken along line 8-8;
[0042] FIG. 9 is a front perspective view of the handlebar of FIG.
1 connected to a bicycle;
[0043] FIG. 10 is a rear perspective view of the handlebar of FIG.
1 connected to a bicycle;
[0044] FIG. 11 is a side view of the handlebar of FIG. 1 connected
to a bicycle and in a first position;
[0045] FIG. 12 is the side view of FIG. 11 with the handlebar in a
different position; and
[0046] FIG. 13 is a side the side view of FIG. 11 with the
handlebar in a different position.
DETAILED DESCRIPTION
[0047] Various apparatuses or processes will be described below to
provide an example of an embodiment of each claimed invention. No
embodiment described below limits any claimed invention and any
claimed invention may cover processes or apparatuses that differ
from those described below. The claimed inventions are not limited
to apparatuses or processes having all of the features of any one
apparatus or process described below or to features common to
multiple or all of the apparatuses described below. It is possible
that an apparatus or process described below is not an embodiment
of any claimed invention. Any invention disclosed in an apparatus
or process described below that is not claimed in this document may
be the subject matter of another protective instrument, for
example, a continuing patent application, and the applicants,
inventors or owners do not intend to abandon, disclaim, or dedicate
to the public any such invention by its disclosure in this
document.
[0048] The handlebars of a bicycle generally serve as a point of
engagement/contact between the bicycle rider/user and the bicycle
itself (e.g. in addition to the seat and pedals). The handlebars
are usually connected to the steering tube of the bicycle and can
be used to transmit steering forces from the user to the bicycle,
thereby turning the bicycle's front wheel. The handlebar can also
transmit vibrations and other forces to the rider then the bicycle
is in use. For example, when a bicycle is travelling over
relatively rough ground (such as when being ridden off-road) the
impacts and bumps experienced by the front tire of the bicycle as
it traverses over bumps, rocks, roots and other obstacles can be
transmitted via the handlebar to the hands and arms of the rider.
These forces and vibrations may be unpleasant for the rider and/or
may contribute to rider fatigue or injury. While some of the
impacts from the front wheel can be mitigated by using shocks or
other suspension components in the front forks of the bicycle, the
rider may still experience shocks and vibrations via the
handlebar.
[0049] In general, the steering forces exerted on the handlebar to
help steer the bicycle are applied in one direction (e.g. to help
rotate the steering tube about its rotation axis) whereas the
impact forces and vibrations may tend to be applied in a different
direction than the steering forces. A mountain bike, for example,
it may be configured such that the steering forces are applied in a
plane that is generally orthogonal to the steering axis of the
bike--and that is generally in the forward/backward direction of
the bicycle. In some configurations, the steering axis may be
within about 0-45 degrees of a vertical direction (and possibly
between about 10 and about 30 degrees) when the bicycle is in use
and therefore the plane in which the steering forces are acting may
be inclined within about 0-45 degrees from the vertical direction
when the bicycle is in use.
[0050] In contrast to the steering forces, the bumps and vibration
forces may tend to be transferred to the rider in a variety of
different directions (based on the direction of impacts acting on
the front wheel) but may tend to be in what can be considered a
generally up/down direction when the bicycle is in use, or
optionally at an inclination of between about 0-45 (and optionally
between about 10 and about 30 degrees) from a vertical axis and/or
from the steering tube axis when the handlebar and bicycle are in
use.
[0051] Reducing the stiffness or flexural rigidity of the handlebar
may help make the handlebar more compliant/deformable when in use
and may help increase the amount of elastic flexing of the
handlebar while in use. As the handlebar flexes it can absorb at
least some of the vibration energy and can help reduce at least the
magnitude of the forces that are eventually transmitted to the
hands and arms of the rider. However, if a handlebar is too
flexible or compliant it may become less effective at transferring
steering forces to the steering tube which may affect the steering
feel and performance of the bicycle. A less stiff handlebar may
also be more prone to plastic deformation and/or bending when in
use and subjected to relatively high forces/loads.
[0052] Therefore, it may be desirable to provide a handlebar that
can help reduce the transmission of forces/vibrations in one
direction to help improve rider comfort while still being
sufficiently strong and/or stiff in another direction(s) to provide
a desired amount of strength and/or performance. For example, to
help reduce the vibrations experienced by the rider, while still
providing a desired degree of stiffness to transmit steering forces
the exemplary handlebars described herein are configured to have
one stiffness or flexural rigidity in the steering direction and a
different, generally lower stiffness or flexural rigidity in the
rider impact (e.g. generally up/down) direction. Such handlebars
can be relatively more flexible in the up/down direction to help
reduce the transfer of shocks and vibrations to the rider while
riding.
[0053] To help reduce the amount of force transferred to the rider
via the handlebar the teachings described herein relate generally
to a new handlebar that can be less stiff in direction(s) that
transfer force to the rider's hands and arms while still being
sufficiently stiff in other directions to function as intended,
including specifically being sufficiently stiff in the steering
direction. To help facilitate this combination of different bending
stiffnesses the handlebars described herein are configured such
that their cross-sectional shape (e.g. a shape taken in a plane
that is generally orthogonal to the elongate direction of the
handlebar or at least the local section thereof) is different at
different locations along the handlebar. When a handlebar is
configured as a generally elongate, tubular object changing its
cross-sectional shape can change its local mechanical properties,
including its area moment of inertial which can change its bending
stiffness/ flexural rigidity. If the cross-sectional area of the
handle bar is different at different locations along its length,
the handlebar may have different stiffnesses at such locations. In
addition, the handlebars described herein are configured such that
the cross-sectional shape in at least some locations along the
handlebar are non-circular and are configured so that the handlebar
has different widths in at least two different directions. If a
given input force is applied in a direction in which the handlebar
width is relatively small, the handlebar may tend to have a
relatively low stiffness in that direction and may tend to
bend/deflect in response to the force. In contrast, if the same
input force is applied in the direction in which the handlebar
width is relatively large the handlebar may tend to have a
relatively high stiffness in that direction and may tend not to be
bend/ deflect in response to the force or may bend/deflect in this
direction less than it did in the direction with the relatively
small width. Configuring the handlebar with cross-sectional shapes
of this manner may help provide at least a portion of the handlebar
that will have different stiffnesses in different directions. The
cross-sectional shape defined by the handlebar may be any suitable
shape that has at least two different widths (measured in different
directions), including oval, rectangular, other arcuate and curved
shapes, hexagonal and other polygonal shapes and the like if they
are configured to provide different widths.
[0054] Referring to FIG. 1, one example of a handlebar 100 for a
bicycle is illustrated. The handlebar 100 has, in this example, an
elongate and generally tubular body 102 that is configured to be
connected to the steerer tube of a bicycle. Referring also to FIG.
2, for the purposes discussion herein, the handlebar 100 can be
considered to have a length 104 that is measured in a transverse
direction between what would be the laterally spaced apart ends 106
and 108 when the handlebar 100 is mounted to the bicycle. In the
configuration illustrated, the end 106 may be considered to be left
end and end 108 may be considered to be the right end of the
handlebar 100. The length 104 separating the ends may be any
suitable length, and may be selected based on the expected use of
the handlebar 100. For example, the length 104 may be between about
600 mm and about 1000 mm, and may preferably be between about 700
mm and about 900 m and in this illustrated example may be about 800
mm. This handlebar 100 may be suitable for use with a mountain
bike, and in particular a mountain bike configured for downhill
riding.
[0055] Referring also to FIGS. 9-11, in this example the handlebar
100 includes a mounting portion 110 that is shaped to be generally
complimentary to an attachment portion such as a stem 200 that is
mounted to an upper end of the steerer tube 202 on a bicycle 204.
The steerer tube 202 can be supported on bearings and can pivot
relative to the head tube of the bicycle frame about a pivot or
steering axis 206 to facilitate steering of the bicycle. This
mounting portion 110 may be located in any suitable location, but
in most embodiments of the handlebar 100 the mounting portion 110
will be positioned in the centre of the handlebar 100 so that the
handlebar 100 is generally symmetrical when mounted to the bicycle.
The size and shape of the mounting portion 110 can be selected to
match a given bicycle. In this example, the mounting portion 110
extends along a mounting axis 111 that is aligned with the lateral
direction of the handlebar 100 in which the length 104 is measured
(FIG. 2) and has a generally circular cross-sectional shape that is
taken in a plane 112 that is generally orthogonal to transverse
direction and axis 111.
[0056] More detail of the cross-sectional shape is shown in the
cross-sectional view of FIG. 3. In this example, the central
mounting portion 110 is formed from a circular portion of the
handlebar body 102 and has a constant radius 116. In this
arrangement the central mounting portion 110 has a width or
mounting diameter 118 measured in a first direction 120 that is, in
this example generally parallel to the plane 112 and a width 122
that is measured in a second direction 124. Because the central
mounting portion 110 is circular, the widths 118 and 122 are
substantially the same as each other in this example.
[0057] Preferably the direction 124 is arranged so as to be
different than the first direction 120, and to be non-parallel and
inclined relative the first direction 120 by an inclination angle
126 (FIG. 3). The angle 126 can be any suitable angle, and may vary
based on the specific cross-sectional shape of a given embodiment
of the handlebar. In the illustrated example the angle 126 is about
90 degrees and the second direction 124 is orthogonal to the first
direction 120.
[0058] The first direction 120 and second direction 124 are
directions of reference that are described in relation to the
handlebar 100. As illustrated in FIGS. 3 (and FIGS. 4-8) the first
direction 120 is a generally vertical or upright direction, and may
be generally vertical and/or aligned with the axis of rotation 206
of the steerer tube 202 (FIGS. 10 and 11) when the handlebar 100 is
in use on a bicycle. In this configuration the second direction 124
may be substantially horizontal (e.g. at an angle 214 that is less
than about 15 degrees or preferably less than about 10 degrees or
about zero degrees from a horizontal plane/axis 216 as shown in
FIG. 11) when the handlebar 100 is attached to a bicycle with the
first direction 120 being generally vertical in this example. If,
alternatively, the first direction 120 is slightly reclined from
vertical by a larger angle 210, the second direction may be
declined from horizontal axis 216 by an analogous angle 214. In
other arrangements the angle 126 may be less than or greater than
90 degrees, and may be between about 120 degrees and about 60
degrees, or may be between about 110 and about 70 degrees, between
about 100 and 80 degrees and other suitable angles.
[0059] That is, referring also to FIGS. 11-13, the handlebar 100 is
preferably configured so that it can be mounted to the bicycle 204
with its first direction 120 being at an angle 210 relative to a
vertical axis 212 that is within about 45 degrees (measured either
forward or backwards from the axis) and may be within about 40
degrees, within about 35 degrees, within about 30 degrees, within
about 25 degrees, within about 20 degrees and within about 15
degrees of the vertical axis 212. Optionally, the handlebar 100 can
be configured so that when mounted to the bicycle 204 the first
direction 120 is at an angle 220 that is within about 45 degrees,
and may be within about 40 degrees, within about 35 degrees, within
about 30 degrees, within about 25 degrees, within about 20 degrees
and within about 15 degrees relative to the axis of rotation 206 of
the steerer tube 204. Similarly, the second direction 124 is
parallel to the horizontal axis 216 and the angle 214 is zero
degrees. Alternatively the handlebar 100 may be mounted in a
different rotational position relative to the steerer tube 202, and
may be rotated backward such that the first direction 120 is
inclined toward the rider of the bike (FIG. 12) or forward such
that the first direction 120 is inclined forwardly and away from
the rider of the bike (FIG. 13). Optionally, as shown in FIG. 11
the handlebar 100 can be mounted so that the first direction 120 is
substantially vertical and is parallel with the vertical axis 212,
such that the angle 210 is zero degrees. FIGS. 12 and 13 illustrate
exemplary locations of the first and second directions 120 and 124
in these rotated arrangements, as well as the angles 210 and
214.
[0060] In the illustrated example the elliptical cross-sectional
shapes in the transition portion 138 are generally symmetrical in
the first and second directions 120 and 124. That is, the curvature
at the left side of the shape in FIG. 5 is generally the same as
the curvature on the right side of the shaped in FIG. 5, and the
upper and lower sides of the shape (i.e. spaced in the first
direction 120) are also the same. This can help give the handlebar
100 generally consistent mechanical properties in the first and
second directions 120 and 124 when in use. This may be desirable as
it may facilitate providing a similar user/rider resiliency in the
first direction 120 with the flex in response to upward
forces/loading being generally consistent with the flex in response
to downward forces/loading. Symmetry in the second direction may
help ensure that the handlebar 100 has the generally the same
stiffness when responding to a right turning input as it does when
responding to a left turning input from the rider, and in the
illustrated example the elliptical cross-sectional shapes.
[0061] Preferably, the central mounting portion 110 has a constant
or at least substantially constant cross-sectional shape along its
length 128 in the transverse direction. This can help provide a
region of generally constant shape to be received in a
corresponding clamp on a steerer tube. Referring also to FIG. 4, a
cross-sectional shape taken along line 4-4 at the transverse edge
of the central mounting portion 110 is the same as the
cross-sectional shape at plane 112, with the same widths 118 and
124. The length 128 can be any suitable length, and preferably can
be selected to fit standard mounting clamps. The length 128 can be
between about 50 mm and about 80 mm, and can be between about 5%
and about 10% of the overall length 104. In the illustrated example
the length 128 is about 60 mm.
[0062] The central mounting portion 110 also has a wall thickness
that is generally constant in this illustrated example, but in
other examples may have varying thicknesses around its perimeter.
The wall thickness may be any suitable size, and preferably can be
relatively small to help reduce the overall weight of the handlebar
100. In this example, the thickness 130 is between about 1 mm and
about 2 mm.
[0063] The handlebar 100 also includes corresponding body sections
that extend laterally from the sides of the central mounting
portion 110. In the illustrated example, this includes a generally
tubular, left body portion 132 extending from a left side of the
central mounting portion 110 and a generally tubular, right body
portion 134 extending from the opposite side. The left body portion
132 includes a left control portion 136 that extends from the
outboard end 106 of the handlebar 100, and a left transition
portion 138 that extends generally laterally between the control
portion 136 and the central mounting portion 110. The right body
portion 134 includes a control portion 136 that is generally the
same as the control portion 136 on the left body portion 132 and a
transition portion 138 that is generally the same as the left
transition portion 138.
[0064] In this example, the control portions 136 are shaped to
receive and support a variety of functional components, including
grips 222 (FIG. 9), brakes and/or shifting equipment. Each control
portion 136 is configured as a generally elongate, tubular member
in this example and extends generally in the lateral/transverse
direction along a respective control axis 137 (FIG. 2) between
respective inboard ends 141 and outboard ends 143. As shown in this
example, the control axis 137 is linear and the control portions
136 are each straight/linear, or at least substantially linear,
tubular sections. Alternatively, the control axis 137 need not be
linear.
[0065] The control axis 137 may be parallel or at least
substantially parallel to the mounting axis 111, or alternatively
may be arranged at a sweep angle 139 relative to the mounting axis
111 as shown in FIG. 2. The sweep angle 139 may be any suitable
angle including about 0 degrees (i.e. the axes 111 and 139 are
substantially parallel) and between about 0 degrees and about 15
degrees or more, or may be between about 5 degrees and about 10
degrees in some examples. In these configurations the control
portions 136, and grips 222 thereon (FIG. 9) can be considered to
be extending in the lateral/ transverse direction (i.e. the
direction in which width 104 is measured) even though they also
have a limited degree of travel/extend in the front/back direction
because of the sweep angle 139. This may be in contrast to other
handle bar styles in which the control portions and/or grips are
arranged in a substantially forward/backward configuration and/or
are substantially orthogonal to the mounting axis 111. In this
arrangement, each control portion 136 extends in the transverse
direction by a respective transverse length 140 that can be
selected to accommodate a desired arrangement of components.
[0066] The control portion 136 is also configured to have a
generally circular cross-sectional shape as shown in the
cross-sectional view in FIG. 8, taken along line 8-8. This shape
can be selected to help the handlebar 100 accommodate grips (see
grips 222 in FIGS. 9-10) and other components that have an industry
standard, generally round cross-sectional shape. The radius 142 is
generally constant and can be sized based on industry standards
and/or to help be comfortably gripped by a rider. The resulting
width or control diameter 145 of the control portion 136 may be
between about 15 mm and about 30 mm, and in this example is about
22 mm. The control diameter 145 is preferably less than the
mounting diameter 118. The wall thickness 144 of this section can
be selected to provide desired mechanical characteristics, and can
be between about 1 mm and about 3 mm (or other suitable
thicknesses).
[0067] While the central mounting portion 110 and the outboard
control portions 136 can have generally circular and substantially
constant cross-sectional areas, the transition portions 138 can be
configured to help provide the desired difference in bending
stiffness for the handlebar 100. While the right transition portion
138 will be referred to in more detail below, the left transition
portion 138 can have the same features. That is, these portions are
generally symmetrical in the embodiment illustrated, and a
description of features on one side (e.g. the right or left) also
apply to the corresponding features on the other side. For example,
for clarity, some of the features of these body portions are
described below only once, with reference to a given body portion,
but the same features can be included in the other body portion.
Alternatively, it is possible that a handlebar need not be
symmetrical, and features found on one side need not be provided on
the other side.
[0068] Referring also to FIGS. 5-7, in this example the right
transition portion 138 is configured to extend between the control
portion 136 and the central mounting portion 110, and has a
transition length 146 in the transverse direction. In this example,
the transition length 146 is greater than the central length 128
and less than the transverse control length 140. It may optionally
be between about 120 mm and about 170 mm, and is about 150 mm in
this example. This can be between about 15% and about 25% of the
overall length 104.
[0069] Within the transition portion(s) 138 the cross-sectional
shape of the handlebar can vary and at different locations along
its length and at one or more location may have a non-circular
cross-sectional area. For example, the transition portion 138 can
have an inboard end 150 that is configured to generally match the
size and shape of the central mounting portion 110, with a
cross-sectional configuration that is the same as that shown in
FIG. 4. Similarly, the outboard end 152 of the transition portion
138 can have a generally circular cross-sectional area that is
configured to generally match the size and shape of the control
portion 136, with a cross-sectional configuration that is the same
as that shown in FIG. 8. Between its ends 150 and 152, the
cross-sectional shape of the transition portion can vary and can be
non-circular.
[0070] Referring to FIG. 5, the cross-sectional shape of the
transition portion 138 taken along line 5-5 is shown. At this
location, the cross-section shape is generally elliptical or
oval-shaped, having a minor radius 156 measured in the first
direction 120 and a longer, major radius 158 measured in the second
direction 124. In this arrangement the transition portion 138 has,
at this location, a width 162 in the first direction that is
different from and less than the width 160 in the second direction.
In this configuration the flexural rigidity/ bending stiffness of
the transition portion 138 will be different in the first direction
120 than it is in the second direction 124. That is, if the
handlebar 100 is mounted via the central mounting portion 110 and a
given input force is applied to the control portion 136 in a
direction that is generally parallel to the first direction 120, as
shown using arrow F in FIG. 1, the right side of the handlebar 100
will have one stiffness and will yield/bend by a certain amount.
However, when an input force of the same magnitude is applied in a
direction that is generally parallel to the second direction 124,
as shown using arrow F in FIG. 2, the right side of the handlebar
100 will have a different stiffness that is greater than the
stiffness in the second direction 124 and will yield/bend by a
lesser amount in the second direction than the it deflected in the
first direction 120. This may advantageously allow the handlebar
100 to be relatively more compliant in the first direction 120
(e.g. the up and down direction when riding) than it is in the
second direction (e.g. the steering direction when in use). This
may help provide a desired rider/user experience while still
providing a desired degree of stiffness when responding to steering
inputs.
[0071] Referring to also to FIGS. 6 and 7, the cross-sectional
shapes of the transition portion 138 at lines 6-6 and 7-7 are shown
illustrating how these cross-sectional shapes are also generally
elliptical/oval-shaped but have slightly differently sized radiuses
156, 158 and widths 160, 162. This can also contribute to the
different in the stiffness of the transition portion 138 in the
first and second directions 120 and 124.
[0072] The widths 160 and 162 can be any suitable widths and can be
between about 20 mm and about 40 mm, and may each be between about
25 mm and about 35 mm. Optionally, the handlebar 100 can be
configured so that the widths 160 and 162 are each less than the
width 118 of the central mounting portion 110 and greater than the
width 145 of the control portions 136. For illustrative purposes,
section 7-7 is taken at about the center of the transition portion
138 in the transverse direction, that is substantially equally
between the inboard end 150 and the outboard end 152.
Alternatively, there may be some regions in the transition portions
138 in which the width 162 is less than the width 145 of the
control portion 136, and optionally where the width 160 is greater
than the width 118 of the mounting portion 110.
[0073] Optionally, the transition portions 138 can be configured so
that an eccentricity of their cross-sectional shapes (taken a
different locations along the length 146) can range between about
0.5 and about 0.8, and may be between about 0.55 and about 0.75,
where eccentricity "e" is calculated as
e = 1 - ( width in first direction width in second direction ) 2 .
##EQU00002##
For example, Table 1 shows some examples of the widths of the
illustrated cross-sectional shapes of the transition portion 138
and the corresponding eccentricity of the handlebar 100 at that
location.
TABLE-US-00001 TABLE 1 Width (mm) in First Width (mm) in Location
Direction 120 Second Direction 124 e section 5-5 28.5 34.8 0.574
(FIG. 5) section 6-6 23 33 0.717 (FIG. 6) section 7-7 21 27 0.629
(FIG. 7) section 4-4 35 35 0 (FIG. 4) section 8-8 22 22 0 FIG.
(8)
[0074] Optionally, the transition portion can be configured so that
the width 162 can be between about 15 mm and about 30 mm, and the
width 160 can between about 25 mm and about 35mm, and/or so that
the width in the first direction is between about 60% and about 90%
of the width in the second direction.
[0075] In this arrangement, the stiffness in the second direction
124 is greater than the stiffness in the first direction 120, and
the handlebar 100 can be configured such that the second stiffness
is between about 110% and about 150% or more of the first
stiffness, and preferably is greater than about 120% of the first
stiffness and may be greater than about 130% of the first
stiffness.
[0076] The wall thickness 170 within the transition portion 138 may
be any suitable thickness, and may be between about 1 mm and bout 5
mm, and preferably may be between about 1.5 mm and about 3 mm. The
wall thickness 170 may remain constant along the length 146 of the
transition portion 138, or as illustrated may vary along the length
146 such that a thickness 170 toward the inboard end 150 is
generally less than the thickness 170 toward the outboard end
152.
[0077] In some embodiments, the handlebar 100 can be shaped and/or
constructed from a suitable material (including composite materials
such as carbon fibre and metals such as aluminium) so that the
stiffness in the first direction is between about 5.5 (kg/mm) and
about 7.5 (kg/mm) and the stiffness in the second direction is
between about 8 (kg/mm) and about 10 (kg/mm).
[0078] The handlebar 100 can be formed in any suitable manner and
may be formed of integral, one-piece construction. In this
arrangement all of the portions 110, 136 and 138 of the bar may be
formed from the same material and the differences in stiffness,
etc. can be the result of the different shape of the different
portions. Alternatively the handlebar may be formed from two or
more pieces, optionally made from different materials.
[0079] The stiffness of a given handlebar may, for the purposes of
the discussion herein, be determined using any suitable techniques,
including calculations, computer modelling and/or empirical testing
or measurement. For example, one technique for determining the
stiffness of the handlebar (and/or portions thereof) can include
calculating the flexural rigidity of the handlebar as EI (with
units Pa m.sup.4), which is the product of Young's modulus (E,
expressed in Pa) and the second moment of area of the handlebar (I,
measured in m.sup.4), as both terms can be used herein to describe
the resistance offered by a structure while undergoing bending. For
example, the flexural rigidity may be calculated generally as
EI .times. .delta. .times. y .delta. .times. x = .intg. 0 x M
.function. ( x ) .times. dx + C , ##EQU00003##
where y is the transverse displacement of the beam/object at
location x, and M(x) is the bending moment at location x.
[0080] For a circular section of the handlebar,
I x = I y = .pi. 4 .times. r 4 , ##EQU00004##
whereas for an oval cross-sectional having a major radius "a" in
the x direction and a minor radius "b" in the y direction
I y = n 4 .times. b 3 .times. a .times. and .times. I x = .pi. 4
.times. ab 3 ##EQU00005##
[0081] Table 2 includes some empirical measurements of stiffness
obtained by testing the handlebar 100 by subjecting it to loading.
Handlebar 100 was mounted in a test fixture and loads were applied
to both left and right control portions is a first directions and a
second direction. In each load case the deflection was measured at
the control area.
TABLE-US-00002 TABLE 2 Direction 2 Direction 1 Stiffness Stiffness
Dir 2 Stiffness/ Description (kg/mm) (kg/mm) Dir 1 Stiffness
Present embodiment 8.6 6.4 1.33 Present embodiment 9.1 6.8 1.34
Present embodiment 8.8 6.6 1.34 average Competitor 1 5.4 7.2 0.75
Competitor 2 6.8 8.9 0.77 Competitor 3 6.3 8.9 0.70 Competitor 6
6.2 8.4 0.74 Competitor 7 6.4 7.9 0.81 Competitor 8 6.4 7.6 0.85
Competitor 9 6.3 8.0 0.79 Competitor 10 6.5 8.9 0.74 Competitor 11
9.8 10.1 0.97 Competitor 12 10.4 10.8 0.96 Competitor 13 6.9 7.3
0.95 Competitor Average 7.0 8.5 0.82
[0082] While this invention has been described with reference to
illustrative embodiments and examples, the description is not
intended to be construed in a limiting sense. Thus, various
modifications of the illustrative embodiments, as well as other
embodiments of the invention, will be apparent to persons skilled
in the art upon reference to this description. It is therefore
contemplated that the appended claims will cover any such
modifications or embodiments.
[0083] All publications, patents and patent applications referred
to herein are incorporated by reference in their entirety to the
same extent as if each individual publication, patent, or patent
application was specifically and individually indicated to be
incorporated by reference in its entirety.
* * * * *