NZ791034A - Bicycle rear suspension system - Google Patents
Bicycle rear suspension systemInfo
- Publication number
- NZ791034A NZ791034A NZ791034A NZ79103417A NZ791034A NZ 791034 A NZ791034 A NZ 791034A NZ 791034 A NZ791034 A NZ 791034A NZ 79103417 A NZ79103417 A NZ 79103417A NZ 791034 A NZ791034 A NZ 791034A
- Authority
- NZ
- New Zealand
- Prior art keywords
- link
- bicycle
- joint
- binary
- coupled
- Prior art date
Links
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- 230000035939 shock Effects 0.000 claims abstract description 179
- 239000006096 absorbing agent Substances 0.000 claims abstract description 132
- 230000001808 coupling Effects 0.000 claims abstract description 18
- 238000010168 coupling process Methods 0.000 claims abstract description 18
- 238000005859 coupling reaction Methods 0.000 claims abstract description 18
- 210000001503 Joints Anatomy 0.000 claims description 53
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- 238000007906 compression Methods 0.000 description 14
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- ASCUXPQGEXGEMJ-GPLGTHOPSA-N [(2R,3S,4S,5R,6S)-3,4,5-triacetyloxy-6-[[(2R,3R,4S,5R,6R)-3,4,5-triacetyloxy-6-(4-methylanilino)oxan-2-yl]methoxy]oxan-2-yl]methyl acetate Chemical compound CC(=O)O[C@@H]1[C@@H](OC(C)=O)[C@@H](OC(C)=O)[C@@H](COC(=O)C)O[C@@H]1OC[C@@H]1[C@@H](OC(C)=O)[C@H](OC(C)=O)[C@@H](OC(C)=O)[C@H](NC=2C=CC(C)=CC=2)O1 ASCUXPQGEXGEMJ-GPLGTHOPSA-N 0.000 description 1
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Abstract
bicycle may include a front triangle and a rear suspension system that couples the front triangle to a rear wheel and is dampened by at least one shock absorber. The rear suspension system includes a six-bar linkage having two ternary links separated from each other by one or more binary links, such that the two ternary links do not share a common joint. One of the ternary links may comprise a chain stay. In some examples, the other ternary link may comprise the front triangle. In some examples, the other ternary link may comprise a rocker arm coupling a seat stay link to the shock absorber. ch that the two ternary links do not share a common joint. One of the ternary links may comprise a chain stay. In some examples, the other ternary link may comprise the front triangle. In some examples, the other ternary link may comprise a rocker arm coupling a seat stay link to the shock absorber.
Description
BICYCLE REAR SUSPENSION SYSTEM
CROSS-REFERENCES
This application claims the benefit under 35 U.S.C. ยง 119(e) of the priority of
U.S. Provisional Patent Application Serial No. 62/370,815, filed August 4, 2016, the
entirety of which is hereby incorporated by reference for all purposes.
FIELD
This disclosure relates to bicycle rear suspension s. More specifically,
the disclosed ments relate to bicycles having a rear suspension system
comprising a six-bar linkage.
INTRODUCTION
A bicycle rear suspension system improves bicycle comfort and performance,
particularly for mountain bicycles, by allowing the rear wheel of the bicycle to track
the n to some extent. This improves rider comfort by reducing the jarring effects
felt when passing over uneven terrain on a led "hard tail" mountain bicycle (i.e.,
one that lacks a rear sion system), and es performance by increasing
traction between the bicycle and the terrain while pedaling, turning and braking.
Various bicycle rear suspension systems have previously been developed.
For example, U.S. Patent No. 5,628,524 to Klassen et al. describes a rear
suspension system in which a pair of rotatable links connects the rear triangle of a
bicycle to the front triangle and a shock absorber, in a manner resulting in an sshaped
travel path of the rear wheel as the shock absorber is ssed. U.S.
Patent No. 8,066,297 also describes a rear suspension system ing a pair of
rotatable links ting the rear le to the front triangle and a shock absorber,
in which one of the links changes its direction of rotation as the shock er is
compressed, resulting in improved riding characteristics.
U.S. Patent No 8,998,235 to Beale describes a rear suspension system in
which three rotatable linkage members connect the rear wheel of a bicycle to the
front triangle and a shock absorber. Systems such as these may be referred to as
"four-bar linkage systems," with the three linkage members ting for three of
the "bars" and the front triangle accounting for the fourth bar. Four-bar linkage
systems may have rear wheel and pedal-related variables which are dependent
upon variables related to the shock absorber. It may be desirable to have these two
sets of variables independent from one another. Systems such as described in US
8.988,235 to Beale may also have acceleration anti-squat values which are related
to braking anti-rise values. It may be ageous to have anti-squat decoupled
from ise. These variables and values are described in greater detail below.
One goal of a rear suspension system such as those described above is to
provide a relatively firm response to pedaling inputs, as when ascending or riding on
smooth ground, but also to provide a relatively forgiving response to bumps or n
inputs, as when descending or tering rough terrain. This s the
unwanted loss of pedaling energy due to unnecessary shock absorption, while
preserving the desirable properties of the suspension system. There remains
significant room for improvement in this regard.
SUMMARY
The present disclosure provides systems, apparatuses, and methods relating
to rear suspension systems for bicycles.
In some embodiments, a bicycle may e: a frame including a rigid front
triangle; and a rear sion system having a shock absorber and coupling the
front triangle to a rear wheel, the rear suspension in ation with the front
triangle comprising a six-bar linkage having exactly two ternary links ted from
each other by at least one binary link, such that the two ternary links have no joints in
common; wherein a first y link of the two ternary links comprises a chain stay
link.
In some embodiments, a bicycle may include: a bicycle frame; and a rear
suspension system coupling the bicycle frame to a rear wheel, the rear suspension
system in combination with the frame comprising a six-bar linkage, the six-bar
linkage including: a chain stay link comprising a first y link coupled at a front
end portion by a first joint to a first binary link and by a second joint to a second
binary link, and coupled at a rear end portion by a third joint to a seat stay link
comprising a third binary link; a fourth binary link coupled by a fourth joint to the seat
stay link; wherein the first binary link is coupled to the bicycle frame by a fifth joint,
the second binary link is coupled to the bicycle frame by a sixth joint, and the fourth
binary link is coupled to the bicycle frame by a seventh joint, such that the bicycle
frame is a second ternary link of the six-bar linkage; and a shock absorber coupling
the fourth binary link to the bicycle frame.
In some embodiments, a bicycle may include: a bicycle frame; and a rear
suspension system coupling the bicycle frame to a rear wheel, the rear sion
system in combination with the frame comprising a six-bar linkage, the six-bar
linkage including: a chain stay link comprising a first ternary link coupled at a front
end portion by a first joint to a first binary link and by a second joint to a second
binary link, and coupled at a rear end portion by a third joint to a seat stay link
comprising a third binary link; a rocker arm coupled by a fourth joint to the seat stay
link; wherein the first binary link is coupled to the rocker arm by a fifth joint, the
second binary link is coupled to the bicycle frame by a sixth joint, and the rocker arm
is coupled to the bicycle frame by a seventh joint, such that the rocker arm
comprises a second y link of the six-bar linkage and the bicycle frame
comprises a fourth binary link of the r linkage; and a shock absorber coupling
the fourth binary link to the bicycle frame.
Features, functions, and advantages may be achieved independently in
various embodiments of the present sure, or may be combined in yet other
embodiments, further details of which can be seen with reference to the ing
description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic right side view of portions of an embodiment of a rear
sion bicycle according to s of the present teachings, showing a shock
absorber in a substantially uncompressed state, .
Fig. 2 is a schematic right side view of the rear suspension bicycle of Fig. 1,
showing the shock absorber in a partially compressed state.
Fig. 3 is a schematic right side view of the rear suspension bicycle of Fig. 1,
showing the shock absorber in a substantially fully ssed state.
Fig. 4 is an illustrative chart depicting dCSL vs. vertical wheel travel for the
bicycle of Fig. 1.
Fig. 5 is an rative chart depicting leverage ratio vs. vertical wheel travel
for the bicycle of Fig. 1.
Fig. 6 is a schematic right side view of portions of another embodiment of a
rear suspension bicycle, g a shock absorber in a substantially uncompressed
state, according to aspects of the present teachings.
Fig. 7 is a schematic right side view of the rear sion e of Fig. 6,
g the shock er in a ntially fully compressed state.
Fig. 8 is a schematic right side view of portions of another embodiment of a
rear suspension bicycle, showing a shock absorber in a substantially uncompressed
state, according to aspects of the present teachings.
Fig. 9 is a schematic right side view of the rear suspension bicycle of Fig. 8,
showing the shock absorber in a substantially fully compressed state.
Fig. 10 is an illustrative chart depicting dCSL vs. vertical wheel travel for the
bicycle of Fig. 8.
Fig. 11 is an illustrative chart depicting leverage ratio vs. vertical wheel travel
for the bicycle of Fig. 8.
Fig. 12 is a schematic right side view of portions of another embodiment of a
rear suspension bicycle, showing a shock absorber in a substantially uncompressed
state, according to aspects of the present teachings.
Fig. 13 is a schematic right side view of the rear suspension bicycle of Fig. 12,
showing the shock absorber in a substantially fully compressed state.
Fig. 14 is a schematic right side view of portions of r embodiment of a
rear suspension bicycle, showing a shock er in a ntially uncompressed
state, according to aspects of the present teachings.
DESCRI PTION
Various aspects and examples of a bicycle having a r linkage rear
suspension ting a rear wheel of the bicycle to the front triangle and a shock
absorber, as well as related methods, are described below and rated in the
associated drawings. Unless otherwise specified, a rear suspension bicycle in
accordance with aspects of the present disclosure, and/or its various components
may, but are not required to, contain at least one of the structure, components,
functionality, and/or ions described, illustrated, and/or incorporated herein.
Furthermore, unless specifically excluded, the process steps, structures,
components, functionalities, and/or variations described, illustrated, and/or
incorporated herein in connection with the present ngs may be included in
other r devices and methods, including being interchangeable between
disclosed embodiments. The following description of various examples is merely
illustrative in nature and is in no way intended to limit the disclosure, its ation,
or uses. Additionally, the advantages provided by the examples and ments
described below are illustrative in nature and not all examples and embodiments
provide the same advantages or the same degree of advantages.
Definitions
The following definitions apply herein, unless otherwise indicated.
"Substantially" means to be more-or-less conforming to the ular
dimension, range, shape, concept, or other aspect modified by the term, such that a
feature or component need not m exactly. For example, a "substantially
cylindrical" object means that the object resembles a cylinder, but may have one or
more deviations from a true er.
"Comprising," "including," and "having" (and conjugations thereof) are used
interchangeably to mean including but not necessarily limited to, and are open-
ended terms not intended to exclude additional, ted elements or method steps.
Terms such as "first", "second", and "third" are used to distinguish or identify
various members of a group, or the like, and are not intended to show serial or
numerical limitation.
"Coupled" means connected, either permanently or releasably, whether
directly or indirectly through intervening components.
Furthermore, the present disclosure generally relates to a e rear
suspension system having particularly desirable riding teristics. These
teristics result from a particular configuration of frame portions and linkage
members that will be described using s terms that have standard meanings in
the field of suspension systems. These terms include:
"Instant center" means the intersection point of two lines, each of which
represents the linear extension of one of the linkage members in the suspension
system. Note that a six-bar linkage system may have a plurality of instant centers.
"Center of curvature" means the center of a circle that intersects the axle of
the rear wheel of the bicycle and has a radius determined from the taneous
travel path of the rear wheel.
"Shock rate" means the ratio of shock compression distance to rear wheel
travel distance.
"Sag" means the compression of the shock absorber when the shock
absorber is compressed by the weight of the rider on the bike.
"Chainstay " or "CSL" means the distance from the axis of the bicycle
bottom bracket (i.e., the axis around which both pedals rotate) to the rear wheel axis.
"Chainstay lengthening" or "dCSL" means the rate of change of chainstay
length as the shock is compressed, or alternatively as the rear wheel of the bicycle
moves vertically upward. The rate of change of tay length may be computed
relative to vertical wheel travel distance.
"d2CSL" means the rate of change of dCSL as the shock is ssed or as
the rear wheel of the bicycle moves vertically upward. The rate of change of dCSL
may be computed relative to al wheel travel distance.
"Braking anti-rise" is a measure of the suspension system's response to
braking, and is defined as a ratio calculated as follows. First, a line is drawn between
the point of contact of the rear wheel with the ground and the t center (defined
above). Then the intersection of this line with a vertical line passing through the front
wheel axle is found. The height of this intersection point above the ground divided by
the height of the center of gravity of the bicycle and the rider is the braking anti-rise
value. It is ntly multiplied by 100 and expressed as a percentage.
"Acceleration anti-squat" is a measure of the suspension system's response
to acceleration, and is defined as a ratio calculated as follows. First, a line is drawn
between the rear wheel axis and the instant center ed above). A second line is
drawn as the chain force line between the front chainring and the rear cassette gear
(for a given gear ratio). A third line is then drawn through the intersection of the first
line (rear wheel point of contact to instant center) and the second line (chain drive
force line) and the rear wheel point of contact. Then the intersection of the third line
with a al line g through the front wheel axle is found. The height of this
intersection point above the ground divided by the height of the center of gravity of
the bicycle and the rider is the acceleration anti-squat value. It is frequently lied
by one hundred, and expressed as a percentage.
A "Stephenson chain" is a type of six-bar e having one four-bar loop and
one ar loop, the linkage including two ternary (i.e., three-joint) links that are
separated from each other by one or more binary (i.e., two-joint) links. Unlike the
Watt type of six-bar e, the two ternary links of a Stephenson chain are not
connected to each other by a shared joint (i.e., no joints in common).
Overview
In general, bicycle rear suspension systems of the t disclosure may
include a six-bar linkage connecting a front triangle of the bike frame to the rear
wheel. Links of the six-bar linkage may have varying lengths and arrangements. In
general, a planar, one degree-of-freedom linkage in the general form known as a
Stephenson chain may be utilized, with two ternary links separated by one or more
binary links. For example, a so-called "Stephenson II" or "Stephenson III" topology
may be utilized. Motion of the linkage may be dampened, e.g., by a shock absorber
device coupled to one or more of the links.
Use of a six-bar linkage in accordance with aspects of the present disclosure
may provide an improved rear suspension as compared to other topologies. Typical
four-bar suspension systems have an inherent dependency characteristic present in
all of the tuned variables of the system. Specifically, in four-bar suspension systems,
if one of the mance variables changes icantly as the suspension moves
from full ion to full compression, then other variables will as well. For e,
there is a relationship n dCSL and the shock rate, and there is a relationship
between pedaling anti-squat and shock rate.
Six-bar systems according to the present teachings allow for r
separation of pedal performance variables from shock performance variables,
essentially giving the system one characteristic for pedaling performance and a
separate characteristic for shock performance. Because of the increased number of
links in the linkage, it is possible to have high rates of change in chain growth (dCSL
and d2CSL) - a desirable goal for pedaling mance - while having very linear (or
at least monotonic) changes in shock rate/leverage ratio - a desirable goal for shock
tuning. Accordingly, the shock rate can be tuned independently from dCSL and
independently from the anti-squat.
Because there is separation between pedal performance variables and shock
tuning variables, it is possible to adjust the geometry of the bike (primarily by
changing the position of the rear axle relative to the bottom bracket) without making
changes to the shock rate. Geometry can be adjusted more easily for different sizes
of bikes without changing key kinematic relationships of the sion system.
Examples, Components, and Alternatives
The following sections describe selected aspects of exemplary rear
suspension systems for bicycles, as well as related systems and/or methods. The
examples in these sections are intended for illustration and should not be interpreted
as limiting the entire scope of the present disclosure. Each section may include one
or more distinct embodiments or examples, and/or contextual or related information,
function, and/or structure.
A. First rative ment
This example bes an illustrative rear suspension e; see Figs. 1-2.
Figs. 1 through 3 depict a schematic right side view of portions of an
embodiment of a rear suspension bicycle, lly indicated at 100. For city,
Fig. 1 shows portions of the frame of the bicycle. Remaining portions of the bicycle,
such as a seat, handlebars, , gears, derailleurs, etc., are unrelated to the
present ngs and are either not shown or are only shown schematically. These
components are well known in the bicycle art.
Bicycle 100 includes a front le 102, a rear wheel 104 having a rear
wheel axis Aw, and a rear triangle, generally ted at 106. Rear triangle 106
comprises a six-bar linkage having a Stephenson III topology, with five links that
move relative to a stationary or ground link formed by the front triangle (i.e., the
frame, in this case the seat tube). Accordingly, bicycle 100 includes a first link 108, a
second link 110, a third link 112, a fourth link 114, and a fifth link 116, each of which
comprises a respective, , substantially rigid member pivotably coupled to one
or more of the other links as described below. Second link 110 may be described as
a chain stay link, because it is in a frame position typical of a bicycle chain stay.
Similarly, third link 112 may be bed as a seat stay link, because it is in a frame
position typical of a bicycle seat stay. Bicycle 100 further includes a shock absorber
118, which is coupled to the linkage at a forward extension of link 114 as shown in
Fig. 1. Generally, the first through fifth links (also referred to as linkage members)
allow the rear wheel axis Aw to move relative to the front triangle as the shock
absorber is compressed. Said another way, the rear wheel pivots relative to the front
triangle as a result of the linkage, and this motion is dampened and, in part, limited
by shock absorber 118.
In some examples, certain features of bicycle 100 may be symmetric with
respect to the plane defined by the bicycle. For example, any of the first through fifth
links 108, 110, 112, 114, and 116 may be right-hand links and bicycle 100 may
further include corresponding left-hand links. The left-hand links may be mirror
images of the right-hand links and may otherwise be identical. In some cases, a left-
hand link and a hand link may form a substantially rigid, ric, link
ing on both left and right sides of the bicycle. Accordingly, any description of a
link should be tood to apply equally well to its symmetric counterpart or to one
side of a single, symmetric link.
In some es, certain es of bicycle 100 may be asymmetric with
respect to the plane defined by the bicycle. In particular, a right-hand component and
a left-hand ent may have a same projection into the plane defined by the
bicycle but may each be disposed a different distance away from the plane of the
bicycle. That is, one side of the e may have one or more components closer to
or r from the center line of the e to accommodate, for example, the
drivetrain which is usually disposed on only one side of the bicycle. In some
examples, a component on one side of the bicycle may be curved while the
corresponding component on the other side of the bicycle may be straight.
With continuing reference to Figs. 1-3, an overview of the six links and seven
joints of the six-bar linkage will now be provided. In general, any or all of the joints
(also referred to as pivotal connections) may include suitable bearings, collets,
and/or the like. In this example, second link 110 and the frame of front triangle 102
are each ternary links, i.e., having three pivoting joints connecting each of them to
other links of the linkage. Specifically, second link 110 is coupled at a front end to
first link 108 by a first rotating joint 120 and to fifth link 116 by a second rotating joint
122, and further coupled at a rear end to third link 112 by a third rotating joint 124.
Front triangle 102 is coupled to fourth link 114 by a fourth rotating joint 126, to fifth
link 116 by a fifth rotating joint 128, and to first link 108 by a sixth rotating joint 130.
Accordingly, the four binary links are connected in the linkage as follows.
Binary link 108 is coupled at a front end to the front triangle by joint 130 and at a rear
end to the second link by joint 120. Binary link 116 is coupled at a front end to the
front triangle by joint 128 and at a rear end to the second link by joint 122. Finally,
binary link 112 is joined to binary link 114 by a seventh rotating joint 132, and to
ternary link 110 by joint 124.
Due to the spacing of joints 120 and 122, second link 110 has a generally
triangular shape, as shown in Figs. 1-3. r, link 110 may be shaped in any
suitable manner that ts with the triangular relationship between its three
. For e, link 110 may have a solid triangular shape, may be formed of
three legs or members arranged in a triangle, or may include fewer or more legs
arranged in a rigid formation facilitating the spacing of joints 120, 122, and 124. For
simplicity, link 110 is shown as a rigid, triangular structure.
In addition to the links and joints that comprise the overall six-bar linkage,
other connections and features may be t to facilitate use of the linkage in a
rear suspension . For example, third link 112 is a binary link, but includes an
additional rotational joint 134 at axis Aw where rear wheel 104 is d to the
suspension. Joint 134 is proximate to but offset from third rotating joint 124 by a
selected distance, e.g., to avoid interference between the wheel axle/hub and the
linkage. In some examples, this selected distance is less than approximately 200
mm. In some examples, this selected distance is less than approximately 100 mm.
The selected distance may be measured center-to-center on the joints. In some
examples, rear wheel 104 may be connected to the chain stay link (i.e., second link
110) instead of the seat stay link (i.e., third link 112) in a similar fashion.
ingly, third link 112 is also shown as a rigid triangular arrangement of
three members, but may include any suitable shape or number of ural
members configured to maintain the relationship between the ng joints.
Additionally, fourth link 114 extends forward of fourth rotating joint 126, creating a
pivoting rocker arm having its fulcrum at joint 126. At the forward end of the rocker
arm, a pivotal connection 136 s link 114 to shock absorber 118, thereby
providing a mechanical dampener for the e by affecting rotation of link 114.
Front triangle 102 includes a bottom bracket shell 140 defining a pedaling axis
Ap, a seat tube 142 providing for attachment of a seat post (not shown), a down tube
144, and a top tube 146. Shock absorber 118 may be disposed in front of the seat
tube and the shock absorber may have a substantially vertical orientation, e.g.,
generally parallel to the seat tube. A pivotal connection 138 couples the shock
absorber and the front le, and is disposed on down tube 144 proximate bottom
bracket shell 140.
The depicted generally vertical disposition and orientation of the shock
absorber in Fig. 1 may have several advantages. In other existing rear suspension
bicycles the shock absorber is often attached to the front le via the top tube.
ng the shock absorber to the top tube imparts forces on the top tube that may
e a reinforced structure, which may increase the weight of the front triangle. In
contrast, as shown in Fig. 1, coupling the shock absorber to the down tube facilitates
a lighter top tube.
Another advantage to orienting shock er 118 in a generally vertical
orientation proximate the seat tube is the space afforded within the front triangle for
other items, such as water s, battery packs, etc. That is, bicycle 100 may have
an empty space 148 between top tube 146 and down tube 144. Empty space 148
may accommodate a water bottle cage (not shown) which could be attached to the
down tube (as is common in standard es). Other existing rear suspension
bicycles having a shock absorber coupled to the top tube typically do not have an
empty space within the front le large enough to accommodate a water bottle
cage.
Shock absorber 118 is configured to attach via pivotal connection 138 to front
triangle 102 and via pivotal connection 136 to the fourth link (i.e., the front end
portion of the rocker arm). The shock absorber may be coupled to the six-bar linkage
of rear triangle 106 via the fourth link, and is therefore ively connected to both
the front triangle and the rear triangle. During operation of the bicycle, the shock
absorber controls the rate and amount of compression of the suspension system due
to inputs from bumps and uneven terrain, and thus controls movement of the rear
wheel 104 relative to the front triangle 102. The shock absorber typically es a
spring and a damper, or ous components that function similarly.
Bicycle 100 may comprise a system, including the six-bar linkage defined by
the five links and the front triangle, along with the shock absorber, having one
degree of freedom. In other words, a single parameter is needed to specify the
spatial pose of the linkage. That is, once a position and orientation any one of the
first through fifth links (and/or the shock absorber) is known relative to the front
le, then a position and orientation of the remainder of the first through fifth links
(and/or the shock er) may be determined.
The six-bar linkage may be configured such that rear wheel rotation axis Aw
traces a non-circular arc when the shock absorber moves between an
uncompressed state and a compressed state. The center of curvature, defined
above, for the non-circular arc may move generally forward as the shock absorber is
compressed. As the center of curvature moves forward, an instantaneous radius of
curvature of the trajectory of the rotation axis may increase. That is, the trajectory of
the rotation axis may have relatively more curvature proximate a point of minimum
compression and relatively less curvature proximate a point of maximum
com pression.
The center of curvature may move from a first location behind pedaling axis
AP to a second location behind, but closer to, the pedaling axis as the shock
absorber moves between an uncompressed state and a compressed state. Along
with any horizontal movement, the center of curvature may also have vertical
nt as the shock absorber is ssed or uncompressed.
The shock rate, defined above, for rear suspension bicycle 100 may rise
generally ly with respect to vertical wheel travel distance as the shock absorber
is ssed from as fully uncompressed state to a fully compressed state. A
ly rising shock rate may be desirable. In some examples, the shock rate may
rise monotonically with vertical wheel travel distance, if not strictly linearly.
A rate of change of tay length, i.e. dCSL defined above, with respect to
al wheel travel distance may be relatively high when the shock absorber is at
sag and relatively low when the shock absorber is more deeply compressed. That is,
dCSL may vary with compression in a manner that is independent of how shock rate
varies with compression. The variation in dCSL with compression may be the
opposite of the variation in shock rate with compression. This independence is
illustrated for bicycle 100 in the charts of Figs. 4 and 5. Fig. 4 is a chart illustrating
the change in dCSL vs. rear wheel travel for bicycle 100, and Fig. 5 is a chart
showing the corresponding change in leverage ratio vs. rear wheel travel. Leverage
ratio is the atical inverse of shock rate.
The independence of changing shock rate with respect to changing chain stay
length is one example of an advantage that six-bar linkage systems may have over
linkage systems having fewer links. Namely, systems of the present disclosure may
generally separate les related to the rear wheel and pedaling axes from
variables related to the shock absorber. Such rear wheel/pedal related variables may
include CSL, dCSL, and d2CSL, among others, and shock absorber d variables
may include ties such as the shock rate and its inverse, the leverage ratio.
In contrast, in rear sion systems having a ar linkage, rear wheel
and pedal-related variables may be dependent upon shock-related variables. In
particular, for a four-bar linkage suspension to have high levels of chain growth at
sag and lower levels of chain growth deeper into travel, the shock rate may also
need to be higher at sag and lower deeper into its travel.
Fig. 1 shows rear suspension e 100 where shock absorber 118 is in a
substantially uncompressed state. Fig. 2 shows rear suspension e 100 where
shock absorber 118 is in a partially compressed state. Finally, Fig. 3 shows bicycle
100 where shock absorber 118 is in a substantially fully compressed state. In moving
from the uncompressed state to the compressed state, first link 108 may first move
in a counter clockwise (CCW) direction and then in a ise (CW) direction with
respect to front joint 130, when viewed from the right side as shown in Figs. 1-3, with
the overall movement being CW. Further, second link 110 may move in a CW
direction, third link 112 may move in a CW direction, fourth link 114 may move in a
CW direction, fifth link 116 may move in a CCW direction, all with t to their
front linkage joints. In addition to rotations of the links, a center of mass of each link
may translate relative to the front triangle as the shock absorber compresses. As the
shock er compresses, rear wheel axis Aw may move closer to seat tube 142.
As described above, e 100 may have a plurality of instant centers with
respect to various arcuate paths, as each of the links may be extended via a line
passing through a pair of pivotal joints of that member, and any two of those lines
may cross. An example of an instant center is presently described with respect to
Fig. 3. First link 108 may be ed via a line Ll passing through its two pivotal
connections at joint 130 and joint 120. Fifth link 116 may be extended via a line L2
passing through its two pivotal connections at joint 128 and joint 122. Lines L1 and
L2 cross at an instant center 160. It will be appreciated that as the shock absorber is
compressed and the first and fifth links , instant center 160 may move
correspondingly.
As mentioned, the first through fifth links may define a plurality of t
centers. Further, a single pair of links may define more than one instant center. For
example, second link 110 has three associated joints (122, 126, and 128). Three
lines may extend through a pair of any two of these pivotal connections and each of
these three lines may ect an extension of another link, say fourth link 114, and
define another instant center.
In some examples there may be three instant centers for a bicycle. In some
examples, if one of the plurality of instant centers has a vertical location that is higher
than a al location of the remainder of the plurality of instant centers, then the
instant center having the highest al location may be used to determine such
values as acceleration anti-squat and/or braking anti-rise, as described below. In
some examples, an effective instant center may be determined based on one or
more of the plurality of instant centers of the links.
In some examples, an instant center of bicycle 100 may move rearward from
an initial location to a final location as the shock absorber is compressed from a
substantially uncompressed state to a ntially fully compressed state. In some
examples, the initial location of an instant center may be in front of pedaling axis Ap.
In some examples, the final location may be in front of the pedaling axis. An instant
center may move in a al direction as the shock absorber is compressed.
As described above, an instant center may be used to define other ties
or variables associated with the rear suspension system, such as acceleration antisquat
and braking anti-rise. An e of determining acceleration anti-squat is
presently described.
A force line F1 may be drawn connecting rear wheel axis Aw and instant
center 160. A chain force line F2 may be drawn based on the front chainring and the
rear te gear. Chain force line F2 may be parallel to a top portion of the chain
WO 27192
n a rear gear and a front gear. An intersection point 162 is defined where
force line F1 crosses chain force line F2. A point of contact 164 (i.e., a contact patch)
is defined between rear wheel 104 and ground 166. A line L3 is drawn between point
of contact 164 and intersection point 162. A vertical line L4 passes through an axle
168 of a front wheel 170 of the e. An intersection 172 of line L3 and line L4
defines the acceleration anti-squat value as the height H1 of intersection 172 above
ground 166. Height H1 may be divided by a height H2 of the combined center of
gravity of the bicycle and the rider and multiplied by 100 in order to express the antisquat
value as a tage. The acceleration anti-squat value may depend upon
which instant center is being considered, which gears are engaged by the chain, the
size of the rider, and the compression of shock absorber 118.
In some examples, the acceleration anti-squat value may decrease as the
shock absorber is compressed. In some examples, the acceleration anti-squat value
may decrease form a value substantially equal to 100% to a value of substantially
equal to zero as the shock absorber is compressed from a fully uncompressed state
to a fully compressed state. In some examples, acceleration anti-squat values
greater than 100% are possible if the height H1 of intersection 172 is greater than
the height H2 of the center of gravity. In some examples, acceleration anti-squat
values less than zero are le if intersection 172 is below ground level.
An example of determining braking anti-rise is presently described. A line L5
may be drawn between point of contact 164 and instant center 160. An ection
174 is where line L5 crosses line L4. A height H3 of intersection 174 above ground
166 is the braking anti-rise value. This value may be divided by the height H2 of the
center of gravity and multiplied by 100 in order to express the braking anti-rise as a
percentage. The braking anti-rise value may depend upon which instant center is
being considered, the size of the rider, and the compression of shock er 118.
In some examples of bicycle 100, the braking anti-rise value may have a
period of decrease followed by a period of increase as the shock er is
ssed from a fully uncompressed state to a fully compressed state. In some
examples, the acceleration anti-squat value may be decoupled from the braking antirise
value as the shock absorber is compressed. In particular, if the ration anti-
squat value generally decreases, while the braking ise value decreases and
then increases as the shock absorber is compressed, then the acceleration anti-
squat value may not depend upon the g anti-rise value.
It may be advantageous to have the acceleration anti-squat value decoupled
from the braking anti-rise value. In systems having only three pivotal links the
acceleration anti-squat values are often related to the braking anti-rise values. In
systems having five pivotal links as described herein, the acceleration anti-squat
values may be unrelated to the braking anti-rise values for any particular
configuration of the five movable links.
Based on the above, this embodiment may be described as a bicycle having a
rear sion system with a generally linear (or monotonically changing) shock
rate, a higher rate of chain stay lengthening in the statically-loaded sag point, and a
rear wheel axle disposed on the seat stay link, where the rotating joint between the
seat stay link and the chain stay link is d within no more than approximately
100 mm (or in some examples no more than approximately 200 mm).
In this and other embodiments described herein, the seat stay link and the
chain stay link are both significantly longer than the remaining movable links. In
some examples, the lengths of the seat stay link and the chain stay link are a
dominant or major contributing factor to the longitudinal position of the rear wheel
relative to the frame and front wheel of the bike. Accordingly, the seat stay link and
the chain stay link may be bed as being d to the frame by the three
other movable (in this case binary) links. However, various length combinations and
relationships between the various links are possible and within the scope of the
present disclosure.
B. onal Illustrative Embodiments
This section describes various additional embodiments of rear sions
for bicycles according to aspects of the present teachings; see Figs. 6-14. All of
these additional embodiments may exhibit one or more of the characteristics
described above, including (i) pedaling-related variables may be separate or
decoupled from shock-related variables, (ii) a change in shock rate or ge ratio
may be independent of a rate of change of chainstay length (dCSL), (iii) generally
linear or monotonic sing shock rate with vertical wheel travel, (iv) decreasing
chain growth with al wheel travel, and (v) a decreasing anti-squat value as the
shock absorber is compressed.
Figs. 6 and 7 are schematic depictions of another illustrative rear suspension
bicycle 200, which is similar to bicycle 100 and also comprises an example of a
Stephenson III topology. r components of bicycle 200 are named and
numbered as their substantially similar rparts in bicycle 100. For example,
front triangle 202 is similar to front triangle 102, and is joined to rear wheel 204 by
rear triangle 206, corresponding to rear wheel 104 and rear triangle 106. Other than
as described below, correspondingly ed ents are substantially as
described above. Fig. 6 shows bicycle 200 with a shock absorber 218 in a
substantially uncompressed state and Fig. 7 shows bicycle 200 with shock absorber
218 in a substantially fully compressed state.
Bicycle 200 may differ from bicycle 100 in the exact disposition and
orientation of the first through fifth links, here referred to as links 208, 210, 212, 214,
and 216. For example, first link 208 and fifth link 216 in this example are joined to the
bike frame more closely together than in the example of bicycle 100. Specifically, the
d joints are spaced closer together than are the rear joints of these links. In
contrast, joints 128 and 130 are spaced farther apart than joints 120 and 122 (see
Figs. 1-3). As with bicycle 100, second link 210 may be described as a chain stay
link, because it is in a frame position typical of a bicycle chain stay, and third link 212
may be described as a seat stay link, because it is in a frame position typical of a
bicycle seat stay.
With continuing reference to Figs. 6-7, an overview of the six links and seven
joints of this six-bar linkage will now be provided. As described above, any or all of
the pivotal connections may include suitable bearings, collets, and/or the like. In this
e, second link 210 and the frame of front le 202 are each ternary links,
i.e., having three pivoting joints connecting each of them to other links of the linkage.
Specifically, second link 210 is d at a front end to first link 208 by a first
rotating joint 220 and to fifth link 216 by a second rotating joint 222, and further
coupled at a rear end to third link 212 by a third rotating joint 224. Front triangle 202
is coupled to fourth link 214 by a fourth rotating joint 226, to fifth link 216 by a fifth
rotating joint 228, and to first link 208 by a sixth rotating joint 230.
Accordingly, the four binary links are connected in the linkage as follows.
Binary link 208 is coupled at a front end to the front triangle by joint 230 and at a rear
end to the second link by joint 220. Binary link 216 is coupled at a front end to the
front triangle by joint 228 and at a rear end to the second link by joint 222. Finally,
binary link 212 is joined to binary link 214 by a seventh rotating joint 232, and to
ternary link 210 by joint 224.
Due to the spacing of joints 220 and 222, second link 210 has a lly
triangular shape, as shown in Figs. 6-7. However, link 210 may be shaped in any
suitable manner that ts with the triangular onship between its three
joints. For example, link 210 may have a solid triangular shape, may be formed of
three legs or members arranged in a triangle, or may include fewer or more legs
arranged in a rigid formation facilitating the spacing of joints 220, 222, and 224. For
simplicity, link 210 is shown as a rigid, ular structure.
In addition to the links and joints that comprise the overall six-bar linkage,
other tions and features may be present to tate use of the e in a
rear suspension system. For example, third link 212 is a binary link, but includes an
onal rotational joint 234 at axis Aw where rear wheel 204 is coupled to the
suspension. Joint 234 is offset from third rotating joint 224, e.g., to avoid interference
between the wheel axle/hub and the linkage. Accordingly, third link 212 is also
shown as a rigid triangular arrangement, but may include any suitable shape or
number of structural members configured to maintain the relationship between the
ng joints. Additionally, fourth link 214 extends forward of fourth rotating joint
226, creating a pivoting rocker arm having its fulcrum at joint 226. At the forward end
of the rocker arm, another rotating joint 236 couples link 214 to shock absorber 218,
thereby providing a mechanical dampener for the linkage by affecting rotation of link
As the shock absorber moves from the substantially uncompressed state (Fig.
6) to the substantially compressed state (Fig. 7), all five of the e links rotate in
a CW direction with respect to their respective forward joints. In general, because
fifth link 216 is coupled to front triangle 202 at a position that is vertically lower than
its rear joint 222, upward motion of the rear wheel causes the rear end of link 216 to
pivot upward as well. In contrast, fifth link 116 of bike 100 is coupled to front triangle
102 at a on that is vertically higher than its rear joint 122, and upward motion of
the rear wheel causes the rear end of link 116 to pivot downward.
In some examples, as shock absorber 218 is compressed from a fully
uncompressed state to a fully compressed state a braking anti-rise value may have a
period of increase followed by a period of decrease. This may generally be the
opposite behavior of the braking anti-rise value of bicycle 100. However, an
acceleration anti-squat value for bicycle 200 may generally decrease with
compression of the shock absorber, a behavior that may be substantially similar to
bicycle 100. Again, the difference between bicycle 200 and bicycle 100 illustrates
how, in six-bar rear suspension systems having five movable links, the g anti-
rise value may be decoupled from the acceleration anti-rise value. In contrast, in
four-bar rear suspension systems having three e links, the braking anti-rise
value is often d to the acceleration anti-rise value.
Figs. 8 and 9 are schematic depictions of another illustrative rear suspension
bicycle 300, which is similar to bicycles 100 and 200, and also comprises an
example of a Stephenson III gy. Similar components of bicycle 300 are named
and numbered as their substantially similar counterparts in bicycle 100. For example,
front triangle 302 is similar to front triangle 102, and is joined to rear wheel 304 by
rear triangle 306, ponding to rear wheel 104 and rear triangle 106. Other than
as described below, correspondingly numbered components are substantially as
described above. Fig. 8 shows bicycle 300 with a shock er 318 in a
substantially uncompressed state and Fig. 9 shows e 300 with shock absorber
318 in a substantially fully compressed state.
Bicycle 300 may differ from bicycle 100 and e 200 in the exact
disposition and orientation of the first through fifth links, here referred to as links 308,
310, 312, 314, and 316. For example, the lower front joint of link 310 is generally
configured to move into and out of the space between the forward joints of the first
and fifth links. In contrast, for example, joint 120 is disposed rearward of joints 128
and 130 at all times. However, upper front joint 122 of link 110 in bicycle 100 does
travel into and out of the space between joints 128 and 130. Accordingly, this portion
of the linkage of bicycle 300 may, in some ts, be regarded as an upside down
version of the corresponding portion of the linkage of bicycle 100. As with e
100, second link 310 may be bed as a chain stay link, because it is in a frame
position typical of a bicycle chain stay, and third link 312 may be described as a seat
stay link, because it is in a frame position typical of a bicycle seat stay.
With continuing reference to Figs. 8-9, an overview of the six links and seven
joints of this six-bar linkage will now be provided. As described above, any or all of
the pivotal connections may include suitable bearings, collets, and/or the like. In this
example, second link 310 and the frame of front triangle 302 are each ternary links,
i.e., having three pivoting joints connecting each of them to other links of the linkage.
Specifically, second link 310 is coupled at a front end to first link 308 by a first
rotating joint 320 and to fifth link 316 by a second rotating joint 322, and further
coupled at a rear end to third link 312 by a third rotating joint 324. Front triangle 302
is coupled to fourth link 314 by a fourth rotating joint 326, to fifth link 316 by a fifth
rotating joint 328, and to first link 308 by a sixth rotating joint 330.
Accordingly, the four binary links are connected in the e as follows.
Binary link 308 is coupled at a front end to the front triangle by joint 330 and at a rear
end to the second link by joint 320. Binary link 316 is coupled at a front end to the
front le by joint 328 and at a rear end to the second link by joint 322. Finally,
binary link 312 is joined to binary link 314 by a h rotating joint 332, and to
ternary link 310 by joint 324.
Due to the spacing of joints 320 and 322, second link 310 has a generally
triangular shape, as shown in Figs. 8-9. However, link 310 may be shaped in any
suitable manner that comports with the triangular relationship between its three
. For e, link 310 may have a solid triangular shape, may be formed of
three legs or members arranged in a triangle, or may include fewer or more legs
arranged in a rigid formation facilitating the spacing of joints 320, 322, and 324. For
simplicity, link 310 is shown as a rigid, triangular structure.
In addition to the links and joints that comprise the l six-bar linkage,
other connections and features may be t to facilitate use of the linkage in a
rear suspension . For example, third link 312 is a binary link, but includes an
additional rotational joint 334 at axis Aw where rear wheel 304 is d to the
suspension. Joint 334 is offset from third rotating joint 324, e.g., to avoid interference
between the wheel axle/hub and the linkage. Accordingly, third link 312 is also
shown as a rigid triangular arrangement, but may include any suitable shape or
number of structural members configured to maintain the relationship between the
ng joints. Additionally, fourth link 314 extends forward of fourth rotating joint
326, ng a pivoting rocker arm having its fulcrum at joint 326. At the forward end
of the rocker arm, another rotating joint 336 couples link 314 to shock er 318,
thereby providing a mechanical er for the linkage by affecting on of link
314.
As the shock absorber moves from the substantially uncompressed state (Fig.
8) to the substantially compressed state (Fig. 9), all of the movable links rotate in a
CW direction with respect to their respective forward joints except first link 308,
which moves in a CCW direction. Upward motion of the rear wheel causes second
link 310 to pivot upward, pulling its forward end rearward and pulling joint 320 of first
link 308 to the rear as well. This is analogous to the movement of fifth link 116 of
bike 100, which is configured such that upward motion of the rear wheel causes the
rear end of link 116 to pivot downward.
In some examples, as shock absorber 318 is compressed from a fully
uncompressed state to a fully compressed state a braking anti-rise value may
generally increase. This may lly be different behavior of the braking anti-rise
values of e 100 and/or bicycle 200. However, an acceleration quat value
for bicycle 300 may generally decrease with ssion of the shock absorber, a
behavior that may be substantially similar to bicycle 100.
Figs. 10 and 11 show respective charts of dCSL and leverage ratio vs. vertical
wheel travel ponding to the suspension of bicycle 300.
Figs. 12 and 13 are schematic depictions of a rear suspension bicycle 400,
which is similar to bicycles 100, 200, and 300, but which comprises a Stephenson II
topology, as described below. r components of bicycle 400 are named and
numbered as their substantially similar counterparts in bicycle 100. For example,
front triangle 402 is similar to front triangle 102, and is joined to rear wheel 404 by
rear le 406, corresponding to rear wheel 104 and rear triangle 106. Other than
as described below, correspondingly numbered components are substantially as
described above. Fig. 12 shows bicycle 400 with a shock absorber 418 in a
substantially uncompressed state and Fig. 13 shows bicycle 400 with shock
absorber 418 in a substantially fully compressed state.
Bicycle 400 may differ from bicycles 100, 200, and 300 in the exact
disposition and orientation of the first through fifth links, here referred to as links 408,
410, 412, 414, 416. Additionally, bicycle 400 may further differ with respect to which
links are coupled to which. In particular, rather than being joined to front triangle 402,
fifth link 416 shares a floating, rotating joint 428 with fourth link 414. Accordingly,
links 410 and 414 are the ternary links in this example, as opposed to link 410 and
the bike frame, and the overall topology is that of a Stephenson II chain as opposed
to a Stephenson III chain. As with bicycle 100, second link 410 may be described as
a chain stay link, because it is in a frame position typical of a bicycle chain stay, and
third link 412 may be described as a seat stay link, because it is in a frame on
l of a e seat stay.
With continuing reference to Figs. 12-13, an overview of the six links and
seven joints of this six-bar linkage will now be provided. As described above, any or
all of the pivotal connections may include suitable bearings, s, and/or the like.
In this example, second link 410 and fourth link 414 are each ternary links, i.e.,
having three pivoting joints connecting each of them to other links of the linkage.
Specifically, second link 410 is coupled at a front end to first link 408 by a first
ng joint 420 and to fifth link 416 by a second rotating joint 422, and further
coupled at a rear end to third link 412 by a third rotating joint 424. Fourth link 414 is
coupled to front triangle 402 by a fourth rotating joint 426, to third link 412 by a
seventh rotating joint 432, and to fifth link 416 by joint 428 as described above.
ingly, the four binary links are connected in the linkage as follows.
Binary link 408 is coupled at a front end to the front triangle by joint 430 and at a rear
end to the second link by joint 420. Binary link 416, which is longer than
ponding links 116, 216, 316, is coupled at an upper/front end to the rocker arm
(rearward of the main fulcrum) by joint 428 and at a lower/rear end to the second link
by joint 422. y, binary link 412 is joined to ternary link 414 by a seventh rotating
joint 432, and to ternary link 410 by joint 424.
Due to the spacing of joints 420 and 422, second link 410 has a generally
triangular shape, as shown in Figs. 12-13. However, link 410 may be shaped in any
suitable manner that comports with the triangular relationship between its three
joints. For e, link 410 may have a solid triangular shape, may be formed of
three legs or members arranged in a triangle, or may include fewer or more legs
arranged in a rigid formation facilitating the spacing of joints 420, 422, and 424. For
simplicity, link 410 is shown as a rigid, triangular structure.
In addition to the links and joints that comprise the overall six-bar linkage,
other connections and es may be present to facilitate use of the linkage in a
rear suspension system. For example, third link 412 is a binary link, but includes an
additional onal joint 434 at axis Aw where rear wheel 404 is coupled to the
suspension. Joint 434 is offset from third rotating joint 424, e.g., to avoid interference
between the wheel axle/hub and the linkage. Accordingly, third link 412 is also
shown as a rigid triangular arrangement, but may include any suitable shape or
number of structural members configured to maintain the relationship n the
rotating joints. Additionally, fourth link 414 extends forward of fourth rotating joint
426, creating a pivoting rocker arm having its fulcrum at joint 426. At the d end
of the rocker arm, another rotating joint 436 couples link 414 to shock absorber 418,
thereby providing a mechanical dampener for the linkage by affecting rotation of link
As the shock absorber moves from the substantially uncompressed state (Fig.
12) to the ntially compressed state (Fig. 13), all five of the movable links rotate
in a CW direction with respect to their tive forward , and may translate in
a generally vertical direction. In some examples, as shock absorber 418 is
ssed from a fully uncompressed state to a fully compressed state a braking
anti-rise value may have a period of decrease followed by a period of increase. This
may qualitatively be similar to behavior of the braking anti-rise values of bicycle 100
and qualitatively different from the behavior of the braking anti-rise values of bicycle
200 and/or bicycle 300. However, an acceleration anti-squat value for e 400
may generally decrease with compression of the shock absorber, a behavior that
may be substantially similar to bicycle 100.
Fig. 14 is a schematic depiction of another rear sion bicycle 500, which
is r to bicycles 100, 200, 300, 400. Similar components of bicycle 500 are
named and numbered as their substantially similar counterparts in bicycle 100. For
example, front triangle 502 is similar to front triangle 102, and is joined to rear wheel
504 by rear triangle 506, corresponding to rear wheel 104 and rear triangle 106.
Other than as described below, correspondingly numbered components are
substantially as described above. Fig. 14 shows bicycle 500 with a shock absorber
518 in a substantially uncompressed state.
Bicycle 500 may differ from bicycle 100 in the exact disposition and
orientation of the first through fifth links, referred to here as links 508, 510, 512, 514,
516, and shock absorber 518. In particular, fourth link 514 may have a different
configuration than fourth link 114 and shock absorber 518 may have a different
disposition and orientation than shock absorber 118. Additionally, third link 512 may
have a greater length than third link 112 as a rotating joint 532 between third link 512
and fourth link 514 may be farther forward than rotating joint 132. As with bicycle
100, second link 510 may be described as a chain stay link, because it is in a frame
position l of a bicycle chain stay, and third link 512 may be bed as a seat
stay link, e it is in a frame position typical of a bicycle seat stay.
In this example, fourth link 514 is coupled to a top tube 546 of front triangle
502 and pivots or rocks on an upper ng joint 526. In contrast, fourth link 114 is
coupled to front triangle 102 at ng joint 126 on seat tube 142. Shock absorber
518 is coupled to fourth link 514 at a rotating joint 536, and to top tube 546 at a
rotating joint 538. In contrast, shock absorber 118 is coupled to the front triangle at
joint 138 proximate bottom bracket shell 140 and/or down tube 144.
As shock absorber 518 moves from the substantially uncompressed state
shown in Fig. 14 to a substantially compressed state, the rocker arm formed by
fourth link 514 rotates in a CCW ion. In contrast, fourth link 114 rotates in a CW
direction as shock er 118 is compressed.
It will be appreciated that the first, second, third, and fifth links of bicycle 500
are most similar to the first, second, third, and fifth links of bicycle 100, respectively,
and that the primary differences between bicycles 500 and 100 are (a) the CW
rotation of the fourth link and (b) the shock absorber being coupled to the top tube. It
will also be appreciated that any or all of bicycles 200, 300, and 400 may also be
reconfigured to include a clockwise rotating fourth link and a shock absorber coupled
to the top tube as shown in Fig. 14.
D. onal Examples and Illustrative Combinations
This section describes additional aspects and es of rear suspension
bicycles, presented without limitation as a series of aphs, some or all of which
may be alphanumerically designated for clarity and efficiency. Each of these
paragraphs can be combined with one or more other paragraphs, and/or with
disclosure from elsewhere in this application in any le manner. Some of the
paragraphs below expressly refer to and further limit other paragraphs, providing
without limitation es of some of the suitable combinations.
Al. A rear suspension e, comprising:
a front triangle; and
a first linkage member, a second linkage member, a third linkage member, a
fourth linkage member, a fifth linkage member, and a shock absorber;
wherein the first linkage member has a pivotal connection with the front
triangle and a pivotal connection with the second linkage member;
wherein the second linkage member has a pivotal connection with the first
linkage member, a pivotal connection with the third linkage member, and a pivotal
connection with the fifth e member;
wherein the third linkage member has a pivotal connection with the second
linkage member, a pivotal connection with a rear wheel on axis, and a pivotal
connection with the fourth linkage member;
wherein the fourth e member has a pivotal connection with the third
linkage member, a pivotal connection with the front triangle, and a pivotal connection
with the shock absorber;
wherein the fifth linkage member has a pivotal connection with the second
linkage member; and
wherein the shock absorber has a pivotal connection with the fourth linkage
member and a pivotal connection with the front triangle, and is configured to control
movement of the first through fifth linkage members relative to the front le.
A2. The rear suspension bicycle of paragraph A1, wherein the fifth linkage
member has a pivotal connection with the front triangle.
A3. The rear suspension bicycle of aph A1, wherein the fifth linkage
member has a pivotal connection with the fourth linkage .
A4. The rear sion bicycle of paragraph A1, wherein the front triangle
includes a seat tube, the shock absorber is disposed in front of the seat tube, and
the shock absorber has a substantially al orientation.
A5. The rear sion bicycle of paragraph A1, n the first through
fifth linkage members, along with the shock absorber, compose a system having one
degree of freedom.
A6. The rear suspension bicycle of paragraph Al, wherein the first, second,
third, fourth, and fifth linkage members and the shock er are configured so
that the rear wheel rotation axis traces a non-circular arc when the shock absorber
moves between an uncompressed state and a compressed state, and wherein an
center of curvature for the rcular arc moves forward as the shock absorber is
compressed.
A7. The rear suspension bicycle of paragraph Al, wherein a shock rate rises
generally linearly with respect to vertical wheel travel distance as the shock absorber
is compressed from a fully uncompressed state to a fully compressed state.
A8. The rear suspension bicycle of aph A7, wherein a rate of change of
chainstay length with respect to vertical wheel travel distance is relatively high when
the shock absorber is at sag and vely low when the shock absorber is more
deeply ssed.
A9. The rear suspension bicycle of aph A8, wherein a change in the
shock rate with respect to vertical wheel travel distance is independent of a rate of
change of a chainstay length with respect to vertical wheel travel distance as the
shock er is compressed.
A10. The rear suspension bicycle of paragraph Al, wherein an t center
moves rd from an initial on in front of a pedaling axis as the shock
absorber is ssed.
A11. The rear suspension bicycle of paragraph A1, wherein the first through
fifth linkage members define a plurality of instant centers.
Al2. The rear suspension bicycle of paragraph A1, wherein an acceleration
anti-squat value decreases as the shock absorber is ssed.
A13. The rear suspension bicycle of paragraph Al2, wherein the acceleration
anti-squat value decreases from a value substantially equal to 100% to a value of
substantially equal to zero as the shock absorber is compressed from a fully
uncompressed state to a fully compressed state.
A14. The rear suspension bicycle of paragraph A1, wherein a braking anti-rise
value has a period of decrease followed by a period of increase as the shock
absorber is compressed from a fully uncompressed state to a fully compressed state.
A15. The rear suspension e of paragraph A1, wherein a braking anti-rise
value has a period of increase followed by a period of decrease as the shock
absorber is compressed from a fully uncompressed state to a fully compressed state.
A16. The rear suspension bicycle of paragraph A1, wherein a braking anti-rise
value generally increases as the shock er is compressed from a fully
uncompressed state to a fully compressed state.
A17. The rear suspension bicycle of aph A1, wherein an acceleration
anti-squat value is decoupled from a braking anti-rise value as the shock absorber is
compressed.
BO. A bicycle comprising:
a frame including a front triangle; and
a rear suspension system having a shock absorber and coupling the front
triangle to a rear wheel, the rear suspension in combination with the front triangle
comprising a six-bar linkage having a Stephenson topology.
Bl. The bicycle of BO, wherein the six-bar e has a Stephenson III
B2. The bicycle of BO, wherein the six-bar linkage has a Stephenson II
topology.
CO. A bicycle comprising:
a frame including a rigid front triangle; and
a rear suspension system having a shock absorber and coupling the front
triangle to a rear wheel, the rear suspension in combination with the front triangle
comprising a six-bar linkage having y two ternary links separated from each
other by at least one binary link, such that the two ternary links have no joints in
common;
wherein a first ternary link of the two ternary links comprises a chain stay link.
Cl. The bicycle of CO, wherein a second y link of the two ternary links
ses a portion of the front triangle.
C2. The bicycle of C1, wherein the portion of the front triangle is a seat
tube.
C2A. The bicycle of C1, wherein the portion of the front triangle is a top tube.
C3. The e of CO, wherein the chain stay link is coupled at a rear end
portion to a seat stay link by a first rotating joint, and coupled at a front end portion to
a pair of binary links by a second ng joint and a third rotating joint, respectively.
C4. The bicycle of C3, wherein the pair of binary links connect the chain
stay link to a second ternary link.
C5. The e of C4, wherein the second ternary link comprises a portion
of the front triangle.
C6. The bicycle of C3, n one link of the pair of binary links connects
the chain stay link to the front triangle and the other link of the pair of binary links
connects the chain stay link to a second ternary link.
C7. The bicycle of CO, wherein a second ternary link of the two ternary links
comprises a rocker arm coupling a seat stay link to the front triangle.
C8. The bicycle of C7, wherein the rocker arm is coupled to the front
le by a rotating joint and by the shock absorber.
C9. The bicycle of CO, wherein the chain stay link is coupled to the second
ternary link by a total of no more than two binary links.
. The bicycle of C9, wherein one of the no more than two binary links is
a seat stay link.
11. The bicycle of CO, wherein the shock absorber is coupled between a
down tube of the front triangle and one of the links of the six-bar linkage.
C12. The bicycle of 011, n the one of the links ses a rocker
arm rotationally joined to a seat tube of the front triangle.
C13. The bicycle of CO, n the six-bar linkage comprises a seat stay
link coupled to the chain stay link by a first rotating joint, and the rear tire is coupled
to the seat stay link by a second rotating joint that is offset from the first rotating joint
by a selected distance.
C14. The bicycle of C13, wherein the second rotating joint is disposed
proximate and rearward of the first rotating joint.
C15. The bicycle of C13, wherein the selected distance is at most
approximately 200 mm.
DO. A bicycle comprising:
a bicycle frame; and
a rear suspension system ng the bicycle frame to a rear wheel, the rear
suspension system in combination with the frame comprising a six-bar linkage, the
six-bar linkage including:
a chain stay link comprising a first ternary link coupled at a front end n
by a first joint to a first binary link and by a second joint to a second binary link, and
coupled at a rear end portion by a third joint to a seat stay link comprising a third
binary link;
a fourth binary link coupled by a fourth joint to the seat stay link;
n the first binary link is coupled to the bicycle frame by a fifth joint, the
second binary link is coupled to the bicycle frame by a sixth joint, and the fourth
binary link is coupled to the bicycle frame by a seventh joint, such that the bicycle
frame is a second ternary link of the six-bar linkage; and
a shock absorber coupling the fourth binary link to the bicycle frame.
Dl. The e of DO, wherein the fourth binary link extends forward of the
seventh joint, such that the fourth binary link comprises a rocker arm coupled on one
side of the seventh joint to the seat stay link and on the other side of the h
joint to the shock absorber.
D2. The bicycle of D1, wherein the shock absorber is connected between
the fourth binary link and a down tube of the bicycle frame.
D3. The bicycle of DO, wherein the rear wheel is rotatably coupled to the
seat stay link proximate the third joint.
D4. The bicycle of D3, wherein an axle of the rear wheel is spaced less
than approximately 200 mm from the third joint.
D5. The bicycle of DO, n the seventh joint is on a top tube of the
bicycle frame.
D6. The bicycle of DO, n the seventh joint is on a seat tube of the
bicycle frame.
D7. The bicycle of D6, wherein the shock absorber has a generally vertical
orientation.
D8. The bicycle of D6, wherein the shock absorber is generally parallel and
adjacent to the seat tube.
D9. The e of DO, wherein the first and second joints of the chain stay
link are spaced farther apart from each other than are the fifth and sixth joints.
D10. The bicycle of DO, n the first and second joints of the chain stay
link are spaced more closely together than are the fifth and sixth .
D11. The bicycle of DO, wherein the second joint of the chain stay link is
disposed generally between the fifth joint and the sixth joint.
D12. The bicycle of DO, wherein the suspension is transitionable between
an ressed configuration, in which the shock absorber is uncompressed and
the four binary links and the chain stay link are in respective first positions, and a
compressed configuration, in which the shock absorber is compressed and the four
binary links and the chain stay link are in respective second positions, each of the
second positions being oriented in a clockwise direction relative to the respective first
positions when viewed from a right side of the bicycle.
EO. A bicycle comprising:
a bicycle frame; and
a rear suspension system coupling the bicycle frame to a rear wheel, the rear
suspension system in combination with the frame comprising a six-bar linkage, the
six-bar linkage including:
a chain stay link comprising a first y link coupled at a front end portion
by a first joint to a first binary link and by a second joint to a second binary link, and
coupled at a rear end portion by a third joint to a seat stay link comprising a third
binary link;
a rocker arm coupled by a fourth joint to the seat stay link;
wherein the first binary link is coupled to the rocker arm by a fifth joint, the
second binary link is coupled to the bicycle frame by a sixth joint, and the rocker arm
is coupled to the bicycle frame by a seventh joint, such that the rocker arm
comprises a second y link of the six-bar linkage and the bicycle frame
comprises a fourth binary link of the six-bar linkage; and
a shock absorber ng the fourth binary link to the bicycle frame.
El. The bicycle of EO, wherein
the seventh joint defines a fulcrum of the rocker arm, the rocker arm
extending forward of the fulcrum.
E2. The bicycle of E1, wherein the rocker arm is coupled on a rear side of
the fulcrum to the seat stay link and to the chain stay link, and the rocker arm is
coupled on a forward side of the fulcrum to the shock absorber.
E3. The bicycle of E2, n the shock absorber is connected between
the fourth binary link and a down tube of the bicycle frame.
E4. The bicycle of EO, wherein the rear wheel is rotatably coupled to the
seat stay link proximate the third joint.
E5. The bicycle of E4, wherein an axle of the rear wheel is spaced less
than approximately 200 mm from the third joint.
E6. The bicycle of EO, wherein the seventh joint is on a top tube of the
bicycle frame.
E7. The bicycle of EO, wherein the seventh joint is on a seat tube of the
bicycle frame.
E8. The bicycle of E7, wherein the shock absorber has a lly vertical
ation.
E9. The bicycle of E7, wherein the shock absorber is generally parallel and
adjacent to the seat tube.
E10. The bicycle of EO, n the first and second joints of the chain stay
link are spaced more closely together than are the fifth and sixth joints.
El 1 . The bicycle of EO, wherein the second joint of the chain stay link is
disposed generally lower than the sixth joint.
E12. The e of EO, wherein the suspension is transitionable between
an uncompressed configuration, in which the shock absorber is uncompressed and
the four binary links and the chain stay link are in respective first positions, and a
compressed configuration, in which the shock absorber is ssed and the four
binary links and the chain stay link are in respective second positions, each of the
second positions being oriented in a clockwise direction relative to the tive first
positions when viewed from a right side of the bicycle.
Advantages, Features, Benefits
The different embodiments of the bicycle rear sion systems described
herein provide several advantages over known solutions for providing rear
suspension to a bicycle. For example, the illustrative ments of rear
suspension bicycles described herein allow pedaling-related variables to be
led from shock absorber-related variables. Additionally, and among other
benefits, illustrative ments of the rear suspension bicycles bed herein
allow for a linearly or monotonically rising shock rate. Additionally, and among other
benefits, illustrative embodiments of the rear suspension bicycles described herein
allow a change in the shock rate with respect to vertical wheel travel distance to be
independent of a rate of change in chainstay length with t to vertical wheel
travel distance as the shock absorber is compressed. Additionally, and among other
benefits, illustrative embodiments of the rear sion bicycles described herein
allow for an empty space between the top tube and the down tube of the front
triangle for accommodating other bicycle equipment. No known system or device can
m these functions. However, not all embodiments described herein provide the
same advantages or the same degree of advantage.
Conclusion
The disclosure set forth above may encompass multiple distinct examples
with independent utility. Although each of these has been disclosed in its preferred
form(s), the specific embodiments thereof as disclosed and illustrated herein are not
to be considered in a limiting sense, because numerous variations are possible. To
the extent that n headings are used within this sure, such headings are
for organizational purposes only. The subject matter of the disclosure includes all
novel and nonobvious combinations and subcombinations of the s elements,
features, functions, and/or properties disclosed herein. The following claims
particularly point out certain combinations and subcombinations regarded as novel
and nonobvious. Other combinations and subcombinations of features, functions,
elements, and/or properties may be claimed in applications claiming priority from this
or a related application. Such claims, whether broader, narrower, equal, or different
in scope to the original claims, also are ed as ed within the subject
matter of the present disclosure.
WO 27192
Claims (20)
1. A bicycle comprising: a bicycle frame including a front triangle; and 5 a rear suspension system having a shock er and coupling the front triangle to a rear wheel, the rear suspension in combination with the front triangle comprising a six-bar linkage having exactly two ternary links separated from each other by at least one binary link, such that the two y links have no joints in common; 10 wherein a first ternary link of the two ternary links comprises a chain stay link.
2. The bicycle of claim 1, wherein a second ternary link of the two ternary links comprises the front triangle. 15
3. The bicycle of claim 1, wherein the chain stay link is coupled at a rear end portion to a seat stay link by a first rotating joint, and coupled at a front end portion to a pair of binary links by a second rotating joint and a third rotating joint, respectively. 20
4. The e of claim 3, wherein the pair of binary links connect the chain stay link to a second ternary link.
5. The bicycle of claim 4, wherein the second y link comprises the front le.
6. The bicycle of claim 3, wherein one link of the pair of binary links connects the chain stay link to the front triangle and the other link of the pair of binary links connects the chain stay link to a second ternary link. 30
7. The bicycle of claim 1, wherein the shock absorber is coupled between a down tube of the front triangle and one of the links of the six-bar linkage.
8. The bicycle of claim 1, wherein the six-bar linkage comprises a seat stay link coupled to the chain stay link by a first rotating joint, and the rear wheel is coupled to the seat stay link by a second rotating joint that is offset from the first rotating joint by a selected distance.
9. The bicycle of claim 8, wherein the ed distance is at most approximately 200 mm.
10. A bicycle comprising: 10 a bicycle frame; and a rear suspension system coupling the bicycle frame to a rear wheel, the rear suspension system in combination with the frame comprising a r linkage, the six-bar linkage including: a chain stay link comprising a first ternary link coupled at a front end portion 15 by a first joint to a first binary link and by a second joint to a second binary link, and d at a rear end portion by a third joint to a seat stay link comprising a third binary link; a fourth binary link coupled by a fourth joint to the seat stay link; wherein the first binary link is coupled to the bicycle frame by a fifth joint, the 20 second binary link is coupled to the bicycle frame by a sixth joint, and the fourth binary link is coupled to the e frame by a seventh joint, such that the bicycle frame is a second ternary link of the six-bar linkage; and a shock absorber coupling the fourth binary link to the bicycle frame. 25
11. The bicycle of claim 10, wherein the fourth binary link extends forward of the h joint, such that the fourth binary link comprises a rocker arm coupled on one side of the seventh joint to the seat stay link and on the other side of the seventh joint to the shock absorber. 30
12. The bicycle of claim 10, wherein the rear wheel is rotatably coupled to the seat stay link proximate the third joint.
13. The bicycle of claim 10, wherein the seventh joint is on a seat tube of the bicycle frame, and the shock absorber is generally parallel and adjacent to the seat tube. 5
14. The bicycle of claim 10, wherein the first and second joints of the chain stay link are spaced farther apart from each other than are the fifth and sixth joints.
15. A bicycle comprising: a bicycle frame; and 10 a rear suspension system coupling the bicycle frame to a rear wheel, the rear suspension system in combination with the frame comprising a six-bar linkage, the six-bar linkage including: a chain stay link comprising a first ternary link d at a front end n by a first joint to a first binary link and by a second joint to a second binary link, and 15 coupled at a rear end portion by a third joint to a seat stay link comprising a third binary link; a rocker arm coupled by a fourth joint to the seat stay link; wherein the first binary link is coupled to the rocker arm by a fifth joint, the second binary link is coupled to the e frame by a sixth joint, and the rocker arm 20 is d to the bicycle frame by a seventh joint, such that the rocker arm comprises a second ternary link of the six-bar linkage and the bicycle frame comprises a fourth binary link of the six-bar linkage; and a shock absorber coupling the fourth binary link to the bicycle frame. 25
16. The bicycle of claim 15, the rocker arm extending forward of the seventh joint such that the seventh joint defines a fulcrum of the rocker arm, wherein the rocker arm is coupled on a rear side of the m to the seat stay link and to the chain stay link, and the rocker arm is coupled on a forward side of the m to the shock absorber.
17. The bicycle of claim 15, wherein the rear wheel is rotatably coupled to the seat stay link proximate the third joint.
18. The bicycle of claim 15, wherein the seventh joint is on a seat tube of the bicycle frame.
19. The bicycle of claim 15, wherein the shock absorber is lly 5 parallel and adjacent to a seat tube of the frame.
20. The bicycle of claim 15, wherein the first and second joints of the chain stay link are spaced more closely together than are the fifth and sixth joints. WO 27192 0141101.104 ,,-
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US62/370,815 | 2016-08-04 |
Publications (1)
Publication Number | Publication Date |
---|---|
NZ791034A true NZ791034A (en) | 2022-08-26 |
Family
ID=
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