U.S. patent application number 13/171056 was filed with the patent office on 2013-01-03 for vehicle suspension and method.
Invention is credited to Christopher Brian DUNDON.
Application Number | 20130001912 13/171056 |
Document ID | / |
Family ID | 47289042 |
Filed Date | 2013-01-03 |
United States Patent
Application |
20130001912 |
Kind Code |
A1 |
DUNDON; Christopher Brian |
January 3, 2013 |
VEHICLE SUSPENSION AND METHOD
Abstract
The disclosed subject matter relates to a suspension system for
use on a vehicle that includes a knuckle, a first trailing arm
structure, a second trailing arm structure, an upper arm structure,
and a lower arm structure. The first trailing arm structure and
second trailing arm structure can be configured to extend in a
frontward direction from the knuckle to a connection at a forward
portion of a vehicle frame. The upper and lower arm structures can
be configured to extend substantially transversely with respect to
the vehicle longitudinal axis and connect to a rearward portion of
the vehicle frame. The second trailing arm structure can cross
underneath the lower arm structure as viewed from a direction
normal to a plane defined by the central axis and horizontal axis
of the knuckle, such that the second trailing arm structure is
located closer to the travel surface of the vehicle than the lower
arm structure at a location where the second trailing arm structure
crosses underneath the lower arm structure.
Inventors: |
DUNDON; Christopher Brian;
(Pataskala, OH) |
Family ID: |
47289042 |
Appl. No.: |
13/171056 |
Filed: |
June 28, 2011 |
Current U.S.
Class: |
280/124.128 |
Current CPC
Class: |
B60G 2200/182 20130101;
B60G 3/20 20130101; B60G 2200/18 20130101 |
Class at
Publication: |
280/124.128 |
International
Class: |
B60G 3/12 20060101
B60G003/12 |
Claims
1. A suspension system for use on a vehicle, comprising: a knuckle
configured to be attached to a vehicle wheel and including an
aperture having a central axis that corresponds with a rotational
axis of the vehicle wheel when the vehicle wheel is attached to the
knuckle, the knuckle configured to be mounted to a vehicle frame
such that a vertical axis of the knuckle and a horizontal axis of
the knuckle each intersect the central axis of the knuckle and are
perpendicular to the central axis and to each other, the horizontal
axis separating an upper portion of the knuckle from a lower
portion of the knuckle, the upper portion of the knuckle being
spaced further from a travel surface than the lower portion of the
knuckle when the vehicle suspension system is mounted to the
vehicle and the vehicle is located on the travel surface, the lower
portion of the knuckle including a lowermost portion of the knuckle
that is closer to the travel surface than any other portion of the
knuckle, and the vertical axis separating a front portion of the
knuckle from a rear portion of the knuckle; a first trailing arm
structure extending in a frontward direction from the knuckle and
connected to the knuckle via a first connector that has a
rotational axis and the first trailing arm structure is configured
to rotate about the rotational axis of the first connector; a
second trailing arm structure extending in a frontward direction
from the knuckle and connected to the knuckle via a second
connector that has a rotational axis and the second trailing arm
structure is configured to rotate about the rotational axis of the
second connector, the second connector located closer to the
lowermost portion of the knuckle than the first connector; a lower
arm structure extending in a substantially transverse direction
from the knuckle and connected to the knuckle via a lower connector
such that the lower arm structure is configured to rotate about a
rotational axis of the lower connector; and an upper arm structure
extending in a substantially transverse direction from the knuckle
and connected to the knuckle via an upper connector such that the
upper arm structure is configured to rotate about a rotational axis
of the upper connector, the upper connector located a greater
distance from the lowermost portion of the knuckle than the lower
connector, wherein the second trailing arm structure crosses above
the lower arm structure at a crossing location as viewed from a
direction normal to a plane defined by the central axis and the
horizontal axis of the knuckle, such that the second trailing arm
structure is located further from the travel surface than the lower
arm structure at the crossing location where the second trailing
arm structure crosses above the lower arm structure.
2. The suspension system of claim 1, wherein at least one of the
first trailing arm and the second trailing arm includes a tubular
portion.
3. The suspension system of claim 1, further comprising: a vehicle
frame extending in a longitudinal direction of the vehicle from a
frame rearward portion to a frame forward portion, the frame
rearward portion located closer to a rear of the vehicle than the
frame forward portion, wherein the first trailing arm structure and
second trailing arm structure extend and connect to the frame
forward portion.
4. The suspension system of claim 3, wherein the upper arm
structure and lower arm structure extend and connect to the frame
rearward portion.
5. The suspension system of claim 3, wherein the first trailing arm
structure connects to the frame forward portion at a first location
and the second trailing arm structure connects to the frame forward
portion at a second location, the second location being closer to
the travel surface than the first location when the vehicle is
located on the travel surface.
6. The suspension system of claim 5, wherein the first trailing arm
structure connects to the frame forward portion via a first frame
connection structure, and the first frame connection structure has
a rotational axis substantially parallel with the central axis of
the knuckle such that the first trailing arm structure is rotatable
about the first frame connection structure rotational axis.
7. The suspension system of claim 3, wherein the first trailing arm
structure connects to the frame forward portion via a first frame
connection structure and the first frame connection structure has a
rotational axis substantially parallel with the central axis of the
knuckle, the first trailing arm structure is rotatable about the
first frame connection structure rotational axis.
8. The suspension system of claim 1, wherein the rotational axis of
the first connector is spaced from and extends substantially
parallel with the rotational axis of the second connector.
9. The suspension system of claim 1, wherein the rotational axis of
the lower connector of the lower arm structure is substantially
parallel with the horizontal axis of the knuckle.
10. The suspension system of claim 1, wherein the rotational axis
of the upper connector of the upper arm structure is substantially
parallel with the vertical axis of the knuckle.
11. The suspension system of claim 1, wherein the rotational axis
of the first connector is substantially parallel with the central
axis of the knuckle.
12. The suspension system of claim 1, wherein the rotational axis
of the second connector is substantially parallel with the central
axis of the knuckle.
13. The suspension system of claim 1, wherein the crossing location
is defined by an imaginary linear line that is normal to the plane
defined by the central axis and horizontal axis of the knuckle and
which intersects both the second trailing arm and the lower arm
structure.
14. A suspension system for use on a vehicle, comprising: a knuckle
configured to be attached to a vehicle wheel and including an
aperture having a central axis that corresponds with a rotational
axis of the vehicle wheel when the vehicle wheel is attached to the
knuckle, the knuckle configured to be mounted to a vehicle frame
such that a vertical axis of the knuckle and a horizontal axis of
the knuckle each intersect the central axis of the knuckle and are
perpendicular to the central axis and to each other, the horizontal
axis separating an upper portion of the knuckle from a lower
portion of the knuckle, the upper portion of the knuckle being
spaced further from a travel surface than the lower portion of the
knuckle when the vehicle suspension system is mounted to the
vehicle and the vehicle is placed on the travel surface, the lower
portion of the knuckle including a lowermost portion of the knuckle
that is closer to the travel surface than any other portion of the
knuckle, and the vertical axis separating a front portion of the
knuckle from a rear portion of the knuckle; a first trailing arm
structure extending in a frontward direction from the knuckle and
connected to the knuckle via a first connector that has a
rotational axis, the first trailing arm structure being configured
to rotate about the rotational axis of the first connector; a
second trailing arm structure extending in a frontward direction
from the knuckle and connected to the knuckle via a second
connector that has a rotational axis, the second trailing arm
structure being configured to rotate about the rotational axis of
the second connector, and the second connector located closer to
the lowermost portion of the knuckle than the first connector; a
lower arm structure extending in a substantially transverse
direction from the knuckle and connected to the knuckle via a lower
connector such that the lower arm structure is configured to rotate
about a rotational axis of the lower connector; and an upper arm
structure extending in a substantially transverse direction from
the knuckle and connected to the knuckle via an upper connector
such that the upper arm structure is configured to rotate about a
rotational axis of the upper connector, the upper connector located
a greater distance from the lowermost portion of the knuckle than
the lower connector, wherein the second connector is located closer
to the central axis of the knuckle than the lower connector in both
a vertical axis direction and a horizontal axis direction.
15. The suspension system of claim 14, wherein at least one of the
first trailing arm and the second trailing arm includes a tubular
portion.
16. The suspension system of claim 14, further comprising: a
vehicle frame extending in a longitudinal direction of the vehicle
from a frame rearward portion to a frame forward portion, the frame
rearward portion located closer to a rear of the vehicle than the
frame forward portion, wherein the first trailing arm structure and
second trailing arm structure extend and connect to the frame
forward portion.
17. The suspension system of claim 15, wherein the upper arm
structure and lower arm structure extend and connect to the frame
rearward portion.
18. The suspension system of claim 16, wherein the first trailing
arm structure connects to the frame forward portion at a first
location and the second trailing arm structure connects to the
frame forward portion at a second location, the second location
being closer to the travel surface than the first location when the
vehicle is located on the travel surface.
19. The suspension system of claim 17, wherein the first trailing
arm structure connects to the frame forward portion via a first
frame connection structure, and the first frame connection
structure has a rotational axis substantially parallel with the
central axis of the knuckle, the first trailing arm structure being
rotatable about the first frame connection structure rotational
axis.
20. The suspension system of claim 14, wherein the rotational axis
of the first connector is spaced from and extends substantially
parallel with the rotational axis of the second connector.
21. The suspension system of claim 14, wherein the rotational axis
of the lower connector of the lower arm structure is substantially
parallel with the horizontal axis of the knuckle.
22. The suspension system of claim 14, wherein the rotational axis
of the upper connector of the upper arm structure is substantially
parallel with the vertical axis of the knuckle.
23. The suspension system of claim 14, wherein the rotational axis
of the first connector and the rotational axis of the second
connector are substantially parallel with the central axis of the
knuckle.
24. The suspension system of claim 14, wherein the horizontal axis
and vertical axis divide the knuckle into an upper front quadrant,
a lower front quadrant, an upper rear quadrant, and a lower rear
quadrant, and the second connector for the second trailing arm is
located in the lower rear quadrant, the lower connector for the
lower arm structure is located in the lower front quadrant.
25. The suspension system of claim 24, further comprising a second
lower arm extending in a substantially transverse direction from
the knuckle and connected to the knuckle via a second lower
connector such that the lower arm structure is configured to rotate
about a rotational axis of the second lower connector, the second
lower connector located in the lower rear quadrant.
26. The suspension system of claim 14, further comprising a second
lower arm extending in a substantially transverse direction from
the knuckle and connected to the knuckle via a second lower
connector such that the lower arm structure is configured to rotate
about a rotational axis of the second lower connector.
Description
BACKGROUND
[0001] 1. Field
[0002] The presently disclosed subject matter relates to vehicle
suspension systems, and in particular to trailing arm
configurations for vehicle suspension systems and methods for
manufacturing such a suspension system.
[0003] 2. Description of the Related Art
[0004] Vehicle suspension systems can include a complicated set of
linkages, pneumatic devices, and springs that aim to provide a
smooth ride for a vehicle. For example, a four bar linkage
suspension includes a knuckle connected to lower and upper control
arms which in turn are connected to the frame of a vehicle. The
control arms are rotatably connected to the vehicle frame (e.g., by
a "bar" type pivot/connecting device) so that an end can rotate and
move substantially vertically with respect to the vehicle frame. A
knuckle typically connects each of the lower control arms to a
respective upper control arm, and a wheel mount structure can be
attached to the knuckle. Thus, the wheel, when mounted, is
permitted to move in a vertical direction relative to the vehicle
frame. A stabilizer bar can be connected between the left and right
side control arms such that when a particular vertical movement
occurs in a wheel on one side of the vehicle, a corresponding
movement can take place in the corresponding wheel on the other
side of the vehicle. This action prevents roll of the vehicle
during turning and/or maneuvering over rough/bumpy roadway
surfaces.
[0005] A spring is typically connected from one of the upper or
lower control arms or knuckle to the vehicle frame, and a strut or
shock absorber is also connected between the respective control arm
or knuckle and vehicle frame. Thus, the vertical movement of the
wheel can be controlled and damped to provide a relatively smooth
ride for the vehicle.
[0006] Although the above-described four bar suspension system is a
common type of vehicle suspension system, there are other types of
vehicle suspension systems. Another common vehicle suspension
system is the two bar suspension system. In one example of a two
bar suspension system, a lower control arm is pivotally connected
to a vehicle frame. A lower portion of a knuckle can be connected
to the lower control arm and an upper portion of the knuckle can be
connected to a rotary link member that incorporates a spring and
shock absorber system. Thus, the upper control arm is not necessary
in this case.
[0007] Typical vehicle suspension systems often require a great
number of attachment mechanisms, and a great deal of space. The
high number of components and their complex shapes also add cost
and weight to a vehicle. In addition, the large volume required for
these components also creates restrictions in design and also
creates problems during repair in terms of added time required for
repair due to limited access to components, and added cost due to
this added repair time and due to multiple part requirements. The
restriction on design due to the large volume taken by the
suspension system can also result in diminished passenger space
and/or reduced door space for the vehicle, especially with regard
to rear suspension systems and rear doors.
[0008] In particular, existing rear vehicle suspensions include
both single and double trailing arm configurations. As shown in
FIG. 8, a conventional double trailing arm suspension structure
includes a first upper trailing arm 94 and a first lower trailing
arm 99 which extend in the front/rear direction of the vehicle
between the knuckle or wheel connection structure 91 and the
vehicle body 97. A second upper arm 95 extends in a right/left
lateral direction with respect to the vehicle and is located under
the upper trailing arm 94. A second lower arm 92 and third lower
arm 93 are connected via respective bearings with the wheel
connection structure 91 and extend in a right/left lateral
direction with respect to the vehicle. The second lower arm 92 and
third lower arm 93 are located above a point of attachment between
the first lower trailing arm 99 and the wheel connection structure
91. In this particular system, a damper 98 is connected to the
wheel connection structure 91.
[0009] Single trailing arm configurations are also known. For
example, FIG. 6 shows, in schematic form, a conventional pivot
point CP for connecting a single arm to a vehicle frame in a single
arm type suspension system. In this case, the conventional pivot
point CP is located vertically lower and horizontally more forward
than connection pivot points 11AP and 12AP of the dual arm system
depicted in FIG. 1. Several drawbacks are associated with single
trailing arm configurations. For example, because connection pivot
point CP is located in a far forward position relative to the
vehicle's longitudinal axis, the mounting thereof is limited by
frame construction requirements. Thus, the amount of anti-squat
(mechanical compliance) provided by a single arm suspension system
may be reduced. In addition, the far forward position of pivot
point CP can interfere with the rear door entry, requiring either a
smaller door entryway which may interfere with entry and exit
capability for second or third row passengers (depending on type of
vehicle) or reduction in efficiency of the suspension system to
compensate for a larger doorway. In addition, the single trailing
arm configuration is often configured from a single stamped
material, which has limited strength capability as compared to a
tubular trailing arm.
[0010] There is a longstanding need in the art to address the
above-described issues, features and characteristics. The disclosed
subject matter is directed to a vehicle suspension system that can
include a dual trailing arm configuration. As shown in FIG. 6, the
dual trailing arm configuration allows the vehicle suspension
system to act as if it were a single trailing arm system in which
the single trailing arm is connected to the vehicle frame at pivot
point IP (which is located in the door opening of the vehicle).
However, the actual connection between the upper and lower trailing
arms and the vehicle frame of the disclosed dual trailing arm
suspension are located at pivot points 11AP and 12AP, which are
spaced from the door opening of the vehicle. Thus, the suspension
system can provide better rear door access for passengers while
possibly providing a better ride characteristic. The dual arms
allow the wheel to rotate about a virtual arm structure with pivot
point IP. The length of the virtual arm (virtual swing arm length)
can be longer than a length of an actual single swing arm.
SUMMARY
[0011] According to one aspect of the disclosure a vehicle
suspension can include a knuckle configured to be attached to a
vehicle wheel. The knuckle can include an aperture having a central
axis that corresponds with a rotational axis of the vehicle wheel
when the vehicle wheel is attached to the knuckle. The knuckle can
be configured to be mounted to a vehicle frame such that a vertical
axis of the knuckle and a horizontal axis of the knuckle each
intersect the central axis of the knuckle and are perpendicular to
the central axis and to each other. The horizontal axis can
separate an upper portion of the knuckle from a lower portion of
the knuckle, the upper portion of the knuckle being spaced further
from a travel surface than the lower portion of the knuckle when
the vehicle suspension system is mounted to the vehicle and the
vehicle is located on the travel surface. The lower portion of the
knuckle can include a lowermost portion of the knuckle that is
closer to the travel surface than any other portion of the knuckle.
The vertical axis can separate a front portion of the knuckle from
a rear portion of the knuckle. A first trailing arm structure can
extend in a frontward direction from the knuckle and connect to the
knuckle via a first connector that has a rotational axis. The first
trailing arm structure can be configured to rotate about the
rotational axis of the first connector. A second trailing arm
structure can extend in a frontward direction from the knuckle and
connect to the knuckle via a second connector that has a rotational
axis. The second trailing arm structure can be configured to rotate
about the rotational axis of the second connector, and the second
connector can be located closer to the lowermost portion of the
knuckle than the first connector. A lower arm structure can extend
in a substantially transverse direction from the knuckle and
connect to the knuckle via a lower connector such that the lower
arm structure is configured to rotate about a rotational axis of
the lower connector. An upper arm structure can extend in a
substantially transverse direction from the knuckle and connect to
the knuckle via an upper connector such that the upper arm
structure is configured to rotate about a rotational axis of the
upper connector. The upper connector can be located a greater
distance from the lowermost portion of the knuckle than the lower
connector, wherein the second trailing arm structure crosses above
the lower arm structure at a crossing location as viewed from a
direction normal to a plane defined by the central axis and the
horizontal axis of the knuckle, such that the second trailing arm
structure is located further from the travel surface than the lower
arm structure at the crossing location where the second trailing
arm structure crosses above the lower arm structure.
[0012] According to another aspect of the disclosed subject matter,
a vehicle suspension can include a knuckle configured to be
attached to a vehicle wheel and including an aperture having a
central axis that corresponds with a rotational axis of the vehicle
wheel when the vehicle wheel is attached to the knuckle, the
knuckle being configured to be mounted to a vehicle frame such that
a vertical axis of the knuckle and a horizontal axis of the knuckle
each intersect the central axis of the knuckle and are
perpendicular to the central axis and to each other, the horizontal
axis separating an upper portion of the knuckle from a lower
portion of the knuckle, the upper portion of the knuckle being
spaced further from a travel surface than the lower portion of the
knuckle when the vehicle suspension system is mounted to the
vehicle and the vehicle is located on the travel surface. The lower
portion of the knuckle can include a lowermost portion of the
knuckle that is closer to the travel surface than any other portion
of the knuckle, and the vertical axis can separate a front portion
of the knuckle from a rear portion of the knuckle. A first trailing
arm structure can extend in a frontward direction from the knuckle
and connect to the knuckle via a first connector that has a
rotational axis and the first trailing arm structure is configured
to rotate about the rotational axis of the first connector. A
second trailing arm structure can extend in a frontward direction
from the knuckle and connect to the knuckle via a second connector
that has a rotational axis. The second trailing arm structure can
be configured to rotate about the rotational axis of the second
connector, and the second connector can be located closer to the
lowermost portion of the knuckle than the first connector. A lower
arm structure can extend in a substantially transverse direction
from the knuckle and connect to the knuckle via a lower connector
such that the lower arm structure is configured to rotate about a
rotational axis of the lower connector. An upper arm structure can
extend in a substantially transverse direction from the knuckle and
be connected to the knuckle via an upper connector such that the
upper arm structure is configured to rotate about a rotational axis
of the upper connector. The upper connector can be located a
greater distance from the lowermost portion of the knuckle than the
lower connector, wherein the second connector is located closer to
the central axis of the knuckle than the lower connector in both a
vertical axis direction and a horizontal axis direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The disclosed subject matter of the present application will
now be described in more detail with reference to exemplary
embodiments of the apparatus and method, given by way of example,
and with reference to the accompanying drawings, in which:
[0014] FIG. 1 is a perspective view of an embodiment of a
suspension system made in accordance with principles of the
disclosed subject matter.
[0015] FIGS. 2A-D are a front, top, left side, and right side view,
respectively, of the knuckle used in the suspension system shown in
FIG. 1.
[0016] FIGS. 3A-B are a partially assembled rear view, and rear
view, respectively, of the knuckle shown in FIG. 1.
[0017] FIGS. 4A-B are a front partial cross section and side view,
respectively, of the upper trailing arm used in the suspension
system shown in FIG. 1.
[0018] FIG. 5 is a front partial cross section of the lower
trailing arm used in the suspension system shown in FIG. 1.
[0019] FIG. 6 is a driver side rear portion view of a vehicle that
includes the suspension system shown in FIG. 1.
[0020] FIG. 7 is a schematic view of the suspension system shown in
FIG. 1 as compared to a conventional art suspension system.
[0021] FIG. 8 is a side view of a conventional dual trailing arm
suspension system.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0022] A description will now be made below with respect to
examples of apparatuses and methods of the presently disclosed
subject matter with reference to the accompanying drawings and in
accordance with exemplary embodiments of the disclosed subject
matter.
[0023] FIG. 1 shows an exemplary embodiment of a vehicle suspension
system 1 made in accordance with principles of the disclosed
subject matter. The vehicle suspension system 1 can include a
knuckle 10 that is configured to connect to a wheel of a vehicle at
knuckle aperture 100, and can include several connection structures
10R for connecting the knuckle 10 to various structural and
peripheral elements (e.g., for connection to a wheel, brake
elements, etc.). The knuckle 10 depicted is for a driver side rear
suspension system of a vehicle. For purpose of reference, the
longitudinal axis of the vehicle upon which the vehicle suspension
system 1 is mounted will be considered to extend parallel with the
X axis direction shown in FIG. 1. The central axis of the aperture
100 of knuckle 10 coincides with the rotational axis of the wheel
mounted thereto and is considered the Z axis. The Y axis is
considered the height direction of the vehicle suspension system 1.
The X axis, Y axis, and Z axis are all normal with respect to each
other. The front of the vehicle is in a direction shown by arrow F.
Thus, the positive side of the X axis will be considered to extend
from the knuckle 10 in the longitudinal direction and towards the
front of the vehicle (leftward direction in FIG. 1), the positive
side of the Y axis will be considered to be the upward direction in
FIG. 1, and the positive side of the Z axis will be considered
leftward or the out of the paper direction in FIG. 1.
[0024] In this embodiment, an upper trailing arm 12 is connected to
connector structure 10B which can include a through hole located at
the end of an extension arm formed in the knuckle 10. A lower
trailing arm 11 can be connected to the knuckle 10 at connector
structure 10L which, in this embodiment, includes an opening in a
rear side of the knuckle 10 from which a dowel 71 extends (see FIG.
3A).
[0025] A lower transverse arm 14 can be connected to the knuckle 10
at connector structure 10A which can include another opening in the
rear side of the knuckle 10 from which dowel 72 extends. The
connector structure 10A for the lower transverse arm 14 is located
on the knuckle 10 at a position that is further from the central
axis Z of knuckle 10 in both the X-axis and Y-axis directions than
is the connector structure 10L which serves as the connector for
the lower trailing arm 11.
[0026] An upper transverse arm 15 can be connected to the knuckle
10 at connector 10T. The embodiment depicted in FIGS. 1 and 3A
shows the connector 10T which can be configured as a ball joint
attached to the knuckle. Other structures, including bushings,
etc., can be used to form a rotational connection for the upper
transverse arm 15 with respect to the knuckle 10.
[0027] A lower rear transverse arm 13 can be connected to the
knuckle 10 at connector 10C. Connector 10 C can include an aperture
located in an arm extending from a central portion of the knuckle
10. The aperture of connector 10C can cooperate with a bearing and
pivot structure that connect to the lower rear transverse arm 13.
In this particular embodiment, the lower rear transverse arm 13 is
connected to both the vehicle frame 65 and the damper 20. A
stabilizer bar 30 can be connected to the damper 20.
[0028] The specific relationship of the connections between the
above-described structures with respect to the knuckle 10 for the
embodiment depicted in FIG. 1 will now be described. It should be
noted that in the context of the present disclosure, the phrases
"substantially parallel" and "substantially perpendicular" are used
to distinguish between the following three categories of
structures: 1) a longitudinally extending structure (i.e., a
structure that extends generally along a longitudinal direction of
the vehicle to which the vehicle suspension system is attached, for
example, the upper trailing arm 12 and lower trailing arm 11 of the
embodiment of FIG. 1); 2) a transversely extending structure (i.e.,
a structure that extends generally in a direction perpendicular to
the longitudinal direction and height direction of the vehicle, for
example, the upper transverse arm 15, lower transverse arm 14, and
rear lower transverse arm 13 of the embodiment of FIGS. 1); and 3)
a vertically extending structure (i.e., a structure that extends
perpendicular to both the longitudinal and transverse directions of
the vehicle, for example, the post extending from the connection
structure 10T of the embodiment of FIG. 1). Accordingly, the phrase
"substantially parallel" will mean within 45 degrees of a subject
axis (e.g., substantially parallel with the longitudinal axis will
include structures that extend within 45 degrees leftward and 45
degrees rightward of the longitudinal axis). Likewise, the phrase
"substantially perpendicular" will also mean within 45 degrees of a
subject axis (e.g., substantially perpendicular to the longitudinal
axis will include structures that extend within 45 degrees leftward
and 45 degrees rightward of a line that is perpendicular to the
longitudinal axis).
[0029] The upper trailing arm 12 can be connected to the knuckle 10
by a rotational connector that includes a bearing located within an
aperture in the connector. A pin, bolt or other structure can be
used to extend through the bearing and provide the rotational pivot
point for the upper trailing arm 12. Thus, the upper trailing arm
12 extends from the connector 10B in a substantially positive
longitudinal direction (substantially parallel with the
longitudinal axis of the vehicle) from the knuckle 10 and can
rotate about an axis that is substantially parallel with the
central axis Z of the knuckle. The lower trailing arm 11 can be
connected to the knuckle 10 at connector 10L such that the lower
trailing arm 11 can rotate about an axis located at connector 10L
that is substantially parallel with the central axis Z of the
knuckle. Thus, the lower trailing arm 11 and upper trailing arm 12
each extend substantially parallel with the longitudinal axis of
the vehicle.
[0030] By contrast, the lower transverse arms 13 and 14 are
connected to the knuckle 10 at connector 10C and connector 10A,
respectively, such that both the lower transverse arms 13 and 14
can rotate about axes located at connectors 10C and 10A,
respectively, that are each substantially perpendicular to both the
central axis Z and the height axis Y of the knuckle 10. In other
words, both of the lower transverse arms 13 and 14 are connected to
the knuckle 10 such that they can each respectively rotate with
respect to the knuckle 10 about an axis that is substantially
parallel with the longitudinal axis X of the vehicle to which the
suspension system is mounted (and substantially parallel to each
other).
[0031] The upper transverse arm 15 can be connected to the knuckle
10 via the connector 10T which is configured to allow the upper
transverse arm 15 to rotate about an axis that is substantially
perpendicular to both the central axis Z and the longitudinal axis
X. Moreover, the upper transverse arm 15 is connected to the
knuckle 10 such that it can rotate with respect to the knuckle 10
about an axis that is substantially parallel with the height axis
Y.
[0032] FIGS. 2A-D show a front, top, left side and right side view
of the knuckle 10 of the embodiment shown in FIG. 1. The knuckle 10
can be forged, cast, molded, or otherwise manufactured from steel
or alloy thereof, Aluminum and alloys thereof, and possibly from
ceramics, plastics or other materials as well. An aperture 100 can
be located at a substantial center portion of the knuckle 10. The
aperture 100 can have a central axis Z that coincides with a
rotational axis of a wheel that is mounted to the knuckle 10.
Connector 10B can include an arm that extends from a main body of
the knuckle 10 and includes an aperture 102 that has a central axis
that is substantially parallel with the central axis of aperture
100. Connector 10B is located at a position that is spaced from a
main body portion of the knuckle 10 in such a manner that connector
aperture 102 is located substantially centrally with respect to a
positive quadrant of the XY grid shown in FIG. 2A (i.e., at an
approximate 45 degree angle with respect to both the positive X
axis and positive Y axis).
[0033] Apertures 101 and 103 can be located in connector 10A and
10C, respectively, and can each have a central axis that is
substantially perpendicular to both the central axis of aperture
100 and the Y-axis (substantially parallel to the X-axis or
longitudinal axis of the vehicle). In addition, the central axis of
aperture 101 can be substantially parallel with the central axis of
aperture 103 (i.e., the apertures 101, 103 can be offset). As can
be seen in FIG. 2D, the central axis of aperture 101 is located
closer to the origin of the XY graph shown in FIG. 2A than is the
central axis of aperture 103 (the central axis of aperture 101 is
located further in the negative Y-axis direction than the central
axis of aperture 103). In addition, the central axis of aperture
103 is located further in the negative Z-axis direction than is the
central axis of aperture 101.
[0034] FIGS. 3A and 3B show a rear view of the knuckle 10.
Connector 10L is configured for rotational connection to the lower
trailing arm 11 and can include an opening in which a dowel pin 71
is secured by press fit or other attachment means. Likewise,
connector 10A can be configured for rotational connection to the
lower front transverse arm 14 and can include an opening in which a
dowel pin 72 is secured by press fit or other attachment means.
[0035] Connector 10B can be configured for rotational connection to
the upper trailing arm 12 and can include an aperture 102 in which
a bearing 73 is located. The bearing 73 can be configured for
connection to a pin located on a proximal portion of the upper
trailing arm 12. Connector 10C is configured for rotational
connection to the lower rear transverse arm 13 and can include an
aperture 103 in which a bearing 74 is located. The bearing 74 can
be configured for connection to a pin located on a proximal portion
of the lower rear transverse arm 13.
[0036] Connector 10H can be mounted in an aperture located in the
rear face of the knuckle 10. Connector H can be configured as part
of a brake for the vehicle, such as a part of a drum in a disk
parking brake. Of course, other known brake systems can be used in
the presently disclosed subject matter and incorporated at
connector H.
[0037] FIGS. 4A and 4B show a front and side view, respectively, of
the exemplary upper trailing arm 12. The upper trailing arm 12 can
include an elongate bar portion 12E that extends between attachment
structure 12A and attachment structure 12B. The bar portion 12E can
include a cavity 12H such that the bar is formed in a tubular
shape. Attachment structure 12A can be formed as an aperture into
which a bearing is located for attachment to the frame 65 of a
vehicle via a pin, dowel, bolt, or other known attachment
structure. Thus, the upper trailing arm 12 will be attached in a
rotatable manner about attachment structure 12A with respect to the
vehicle frame 65. Attachment structure 12B can include two arms
that extend parallel to each other and in a facing relationship. A
through-hole 12D can be located in each of the arms of the
attachment structure 12B such that a bolt, pin or other known
rotational connection structure can extend through the hole 12D and
rotatably connect to a bearing structure located at connector 10B
of the knuckle 10. The central axis of the aperture of attachment
structure 12A can be parallel or substantially parallel to the
central axis of the through hole 12D.
[0038] FIG. 5 shows a front view of the lower trailing arm 11 of
FIG. 1. The lower trailing arm 11 can include an elongate bar
portion 11E that extends between an attachment structure 11A and an
attachment structure 11B. The bar portion 11E can include a cavity
11H such that the bar is formed in a tubular shape. Attachment
structure 11A can be formed as a structure that defines an aperture
into which a bearing 11D is located for attachment to the frame 65
of a vehicle via a pin, dowel, bolt, or other known pivot
structure. Thus, the lower trailing arm 11 will be attached in a
rotatable manner about attachment structure 11A with respect to the
vehicle frame 65, and at a location that is closer to a travel
surface for the vehicle than the location of the attachment
structure 12D for the upper trailing arm 12. Attachment structure
11B can be located at an opposite end of the bar portion 11E with
respect to attachment structure 11A and can include a structure
that defines an aperture. A bearing 11G can be located in the
aperture of attachment structure 11B for attachment to the knuckle
10 at connector 10L via dowel 71 or other rotational connection
structure. Thus, the lower trailing arm 11 will be attached in a
rotatable manner about attachment structure 11B with respect to the
knuckle 10. The central axis of the aperture of attachment
structure 11A can be parallel or substantially parallel to the
central axis of the aperture of attachment structure 11B.
[0039] FIG. 6 shows a driver side rear portion view of a vehicle
that includes the exemplary vehicle suspension system and includes
schematic markings to compare the geometry and ride characteristics
of the exemplary embodiment of the disclosed subject matter with
respect to a conventional single trailing arm suspension.
[0040] Dotted line 11I and 12I show the orientation of the upper
trailing arm 11 and lower trailing arm 12 of the vehicle suspension
system 1 with respect to the vehicle body 60, door opening 61, and
tire 50 of the vehicle. The actual pivot points 11AP and 12AP at
which the lower trailing arm 11 and upper trailing arm 12 are
connected to the vehicle frame 65 are substantially aligned in a
vertical straight line direction and at a location that is spaced
from the door opening 61. By contrast, the imaginary pivot point IP
at which the dotted lines 11I and 12I intersect is located further
from the knuckle 10 and within the door opening 61. Thus, the
combined upper trailing arm 12 and lower trailing arm 11 provide a
ride geometry for the vehicle suspension 1 that emulates a single
trailing arm attached to the vehicle frame 65 at the imaginary
pivot point IP.
[0041] By comparison, a conventional single trailing arm is
typically attached to the vehicle frame 65 at conventional pivot
point CP. The location of the conventional pivot point CP is
dictated by, among other variables, space restrictions due to the
door opening 61 for the vehicle. Thus, the conventional pivot point
CP is located closer to a travel surface TS for the vehicle than is
the imaginary pivot point IP of the vehicle suspension system
1.
[0042] Dotted lines ET and CT represent the travel path for the
knuckle 10 and wheel structure 50 when using the presently
described embodiment of the vehicle suspension system 1 as compared
to the conventional single arm CA, respectively. Travel path ET has
a greater horizontal or X-axis component than does the travel path
AT. Travel path AT is a more vertically oriented travel path which
results in less dampening and a greater range and amplitude of road
frequency travelling into the conventional vehicle suspension
system and possibly the vehicle body. In other words, the travel
path ET can provide the vehicle with better ride characteristics as
compared to travel path CT.
[0043] FIG. 7 is a schematic drawing depicting the attachment
points for the upper and lower trailing arms 12 and 11 with respect
to the wheel 50 and frame 65 of the vehicle as compared to
connection points for an upper and lower trailing arm of a known or
conventional vehicle suspension system. The view is taken from
along the positive portion of the Z axis normal to both the X and Y
axes, and shows a front of an imaginary/schematic vehicle
suspension system located at a passenger side of a vehicle. The
location of the upper trailing arm 12 is depicted as dotted line
121 and the location of the lower trailing arm 11 is depicted as
dotted line 11I. The location of a conventional upper trailing arm
is depicted as dotted line 12CI and the location of a conventional
lower trailing arm is depicted as dotted line 11CI.
[0044] In addition, the location for attachment of the upper
trailing arm 12 to the knuckle 10 is depicted as point 12PW in FIG.
7. Similarly, the location for attachment of the lower trailing arm
11 to the knuckle 10 is depicted as point 11PW. By contrast, the
location for attachment of the conventional upper trailing arm to a
conventional knuckle is depicted as point 12CPW and the location
for attachment of the conventional lower trailing arm to the
conventional knuckle is depicted as point 11CPW.
[0045] Attachment points 12PV and 11PV show the location of
attachment for the upper and lower trailing arms 11 and 12,
respectively, to the vehicle frame 65. Similarly, attachment points
12CPV and 11CPV show the location of attachment for the upper and
lower conventional trailing arms to a respective vehicle frame. The
upper and lower conventional trailing arms are each mounted at
connection points that are located at a higher position on the
vehicle than their respective counterpart connection points of the
disclosed subject matter. Moreover, the upper trailing arm 12 is
attached to the vehicle frame 65 at a location 12PV that is closer
to the vehicle travel surface TS than is connection location 12CPV
for the conventional upper trailing arm. The lower trailing arm 11
is attached to the vehicle frame 65 at a location 11PV that is
closer to the vehicle travel surface TS than is the connection
location 11CPV for the conventional lower trailing arm.
[0046] Connection point 12CPW denotes the connection location of
the conventional upper trailing arm to the conventional knuckle.
Connection point 12PW denotes the connection location of the upper
trailing arm 12 to the knuckle 10 according to the embodiment of
FIG. 1. Connection point 12CPW is located closer to the Y axis but
further from the X axis than is the connection point 12PW (i.e.,
connection point 12CPW is located further in the vertical direction
from the central axis of the wheel than is connection point 12PW
while also located closer in the horizontal direction to the
central axis of the wheel as compared to connection point 12PW).
The X-Y axis shown in FIG. 7 is centered at (has its origin
coinciding with) the central/rotational axis 10Z (Z-axis) of the
wheel of the vehicle.
[0047] The upper transverse arm 15 is connected to the wheel at
connection point 15P while the conventional upper transverse arm is
connected to the wheel at connection point 15CP. Conventional arm
connection point 15CP is located at a rearward position on the
knuckle, or in the negative X-axis direction, as compared to the
connection point 15P, which is located at a frontward position on
the knuckle 10 and in the positive X-axis direction. Conventional
arm connection point 15CP is also located further in the vertical
Y-axis direction with respect to the knuckle or wheel than is the
connection point 15P, which is located closer to the travel surface
of the vehicle.
[0048] Connection point 11CPW denotes the connection location of
the conventional lower trailing arm to the conventional knuckle.
Connection point 11PW denotes the connection location of the lower
trailing arm 11 to the knuckle 10 according to the embodiment of
FIG. 1. Connection point 11CPW is located further from both the X
and Y axes than is the connection point 11PW (i.e., connection
point 11CPW is located further in both the vertical and horizontal
directions from the central axis 10Z of the wheel than is
connection point 11PW). Thus, the connection point 11CPW is located
closer to the travel surface TS of the vehicle than is connection
point 11PW. Additionally connection point 11PW is located in the
negative X-axis direction and connection point 11CPW is located in
the positive X-axis direction).
[0049] Connection point 13CP denotes the connection location of the
conventional lower rear transverse arm to the conventional knuckle.
Connection point 13P denotes the connection location of the rear
lower transverse arm 13 to the knuckle 10 according to the
embodiment of FIG. 1. Connection point 13CP is located further from
the X axis (in the negative Y-axis direction) than is the
connection point 13P (i.e., connection point 13CP is located
further in the negative vertical direction from the central axis of
the wheel than is connection point 13P). Thus, the connection point
13CP is located closer to the travel surface TS of the vehicle than
is connection point 13P. Connection point 13P is located further
from the Y axis (in the negative X-axis direction) than is the
connection point 13CP (i.e., connection point 13P is located
further in the negative horizontal direction from the central axis
of the wheel than is connection point 13CP). Thus, the connection
point 13P is located further in the rearward longitudinal direction
of the vehicle than is connection point 13CP.
[0050] The connection point 13P is located further from the Y axis
(in the negative X-axis direction) than is the connection point
11PW (i.e., connection point 13P is located further in the negative
horizontal direction from the central axis of the wheel than is
connection point 11PW).
[0051] Connection point 14CP denotes the connection location of the
conventional lower front transverse arm to the conventional
knuckle. Connection point 14P denotes the connection location of
the front lower transverse arm 14 to the knuckle 10 according to
the embodiment of FIG. 1. Connection point 14P is located further
from the X-axis (in the negative Y-axis direction) than is the
connection point 14CP (i.e., connection point 14P is located
further in the negative vertical direction from the central axis of
the wheel than is connection point 14CP). Thus, the connection
point 14P is located closer to the travel surface TS of the vehicle
than is connection point 14CP. Connection point 14CP is located
further from the Y-axis (in the positive X-axis direction) than is
the connection point 14P (i.e., connection point 14CP is located
further in the positive horizontal direction from the central axis
of the wheel than is connection point 14P). Thus, the connection
point 14P is located further in the rearward longitudinal axis
direction of the vehicle than is connection point 14CP.
[0052] Connection point 14P is located at a particular X-axis
location and particular Y-axis location on the X-Y grid (the X-Y
grid being centered at the central/rotational axis 10Z of the
wheel). At the particular X-axis coordinate, the lower trailing arm
11 is located at and passes above the transverse arm 14 that
extends from the connection point 14P.
[0053] By contrast, connection point 14CP is located at a specific
X-axis location and specific Y-axis location on the X-Y grid. At
the specific X-axis coordinate, the conventional lower trailing arm
11CI is located at and passes below a conventional transverse arm
that would extend from the connection point 14CP. This specific
orientation and layout requires a higher vertical mounting point
for the connection point 14CP associated with the conventional
lower transverse arm, and thus reduces camber rigidity as well as
toe control.
[0054] Thus, the front lower transverse arm 14 of FIG. 1 is located
at a position that is closer to the travel surface upon which the
vehicle travels at a point at which the lower trailing arm 11
crosses over the transverse arm 14 (as viewed from a Y-axis
direction at the point of cross over). Alternatively, a linear
imaginary line that is parallel with the Y-axis and intersects both
the lower transverse arm 14 and the lower trailing arm 11 will
intersect the lower transverse arm 14 at a location closer to the
travel surface TS for the vehicle (i.e., further from the X-axis in
the negative Y direction) than the location of intersection of the
linear imaginary line with lower trailing arm 11.
[0055] It should be understood that the connection points described
above are each considered a location at which a first structural
element rotates with respect to a second structural element
connected to the first structural element by the connection point.
In addition, it should be understood that the comparison shown in
FIG. 7 is only for descriptive purposes of a single embodiment of
the disclosed subject matter with respect to a comparative vehicle
suspension system. The specific relationships between the various
components and structures can and will vary greatly depending on
different comparative art suspensions and different embodiments of
the presently disclosed subject matter.
[0056] In particular, many modifications of the disclosed structure
are contemplated that would still fall within the spirit and scope
of the presently disclosed subject matter. Although the different
arm structures are shown as tubular rods, it is contemplated that
the trailing and transverse arms can be made from a pressed
material, molded material, or other non-tubular shape. The various
connection structures depicted in the attached figures are also
exemplary. It should be understood that the connection and
attachment components could be reversed (for example, bearing and
dowel pins can be reversed and placed or incorporated on respective
opposite structures, etc.). In addition, the connection and
attachment structures that are depicted could be replaced with
altogether different connection and attachment structures which can
also have varying different rotational or connective properties
depending on the desired application or desired output of the
vehicle suspension system.
[0057] Although the damper 20 is depicted as a coil over cylinder
damper system, the damper can be any of a shock absorber, strut,
electric amplifier coil, or other known damper. In addition, the
stabilizer bar can be configured in various different manners and
attached to different structures without departing from the spirit
and scope of the presently disclosed subject matter. In fact, it is
contemplated that the stabilizer bar could be removed
altogether.
[0058] The specific geometry of the knuckle 10 can vary greatly
depending on vehicle type, suspension type, type and amount of
peripheral devices to be attached (for example, anti-lock brake
systems and monitors, other sensors, type of brake systems,
etc.).
[0059] While the subject matter has been described in detail with
reference to exemplary embodiments thereof, it will be apparent to
one skilled in the art that various changes can be made, and
equivalents employed, without departing from the scope of the
invention. All related or conventional art references discussed in
the above Description of the Related Art section are hereby
incorporated by reference in their entirety.
* * * * *