U.S. patent application number 12/010930 was filed with the patent office on 2008-08-07 for wheel suspension for motor vehicles.
Invention is credited to Christian Bschierl, Achim Glas, Hans-Jurgen Langhoff, Frank Zuge.
Application Number | 20080185806 12/010930 |
Document ID | / |
Family ID | 39047888 |
Filed Date | 2008-08-07 |
United States Patent
Application |
20080185806 |
Kind Code |
A1 |
Zuge; Frank ; et
al. |
August 7, 2008 |
Wheel suspension for motor vehicles
Abstract
The invention relates to a wheel suspension for motor vehicles,
with at least one upper transverse arm and two lower separated
transverse arms per wheel, which are each arranged at a defined
angle to one another and are articulated to the body of the vehicle
and also to a wheel carrier, furthermore with a track rod which
acts on the steering lever of the wheel carrier and with a
McPherson strut unit which, aligned at a defined angle to the
vertical, is coupled to the body of the vehicle and to the forward
lower transverse arm via a rubber-metal sleeve bearing. To achieve
improved driving comfort of the motor vehicle it is suggested that
at least the forward lower transverse arm is arranged such that the
coupling point of the McPherson strut unit on the transverse arm
when the wheel is deflected viewed in the transverse direction of
the vehicle runs parallel to the longitudinal axis of the McPherson
strut unit.
Inventors: |
Zuge; Frank; (Schelldorf,
DE) ; Glas; Achim; (Gaimersheim, DE) ;
Langhoff; Hans-Jurgen; (Lenting, DE) ; Bschierl;
Christian; (Denkendorf, DE) |
Correspondence
Address: |
Novak, Druce & Quigg LLP
1300 I Street, N.W., Suite 1000, West Tower
WASHINGTON
DC
20005
US
|
Family ID: |
39047888 |
Appl. No.: |
12/010930 |
Filed: |
January 31, 2008 |
Current U.S.
Class: |
280/124.136 |
Current CPC
Class: |
B60G 3/20 20130101; B60G
2202/31 20130101; B60G 3/14 20130101; B60G 2202/12 20130101; B60G
2200/466 20130101; B60G 2200/142 20130101; B60G 2204/129 20130101;
B60G 2200/14 20130101; B60G 2200/18 20130101; B60G 2202/312
20130101; B60G 7/001 20130101 |
Class at
Publication: |
280/124.136 |
International
Class: |
B60G 3/18 20060101
B60G003/18 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 7, 2007 |
DE |
10 2007 005 967.3 |
Claims
1. A wheel suspension for motor vehicles, with two lower separate
transverse arms per wheel, which are arranged at a defined angle
(.beta.) to one another and are articulated to the body of the
vehicle and also to a wheel carrier, furthermore with a McPherson
strut unit which, aligned at a defined angle to the vertical, is
coupled to the body of the vehicle and to the forward lower
transverse arm via a coupling point wherein at least the forward
lower transverse arm is arranged such that the coupling point of
the McPherson strut unit on the transverse arm when the wheel is
deflected and/or steered viewed in the transverse direction of the
vehicle runs within an angle between 0 and 5 degrees, to the
longitudinal axis of the McPherson strut unit.
2. The wheel suspension according to claim 1, wherein the lower
forward transverse arm is positioned essentially in the transverse
direction of the motor vehicle and the rear lower transverse arm is
positioned substantially 45 degrees to the rear tilted inside
thereto.
3. The wheel suspension according to claims 1 wherein the body-side
bearing points of the lower transverse arms are aligned essentially
horizontally and substantially at the same height.
4. The wheel suspension according to claim 1 wherein the tilt of
the McPherson strut unit relative to vertical is aligned within a
range of 5 to 10 degrees up to the rear and up to the inside.
5. The wheel suspension according to claim 4, wherein the
horizontal plane defined by the two lower transverse arms is
aligned almost perpendicular to the tilt of the McPherson strut
unit viewed in the transverse direction of the vehicle.
6. The wheel suspension according to claim 1, wherein the body-side
joint of the forward lower transverse arm in the transverse
direction of the vehicle is designed to be stiffer than in the
direction of the longitudinal axis of the McPherson strut unit.
Description
[0001] The invention relates to a wheel suspension for motor
vehicles according to the preamble of claim 1.
[0002] A wheel suspension such as this is shown, for example, in DE
38 43 613 A1 in which the lower and optionally the upper transverse
arm of the wheel guidance are individual transverse arms which, in
conjunction with a track rod which is articulated to the body or to
the steering of the motor vehicle, form track-stable wheel
guidance. The advantage of such a wheel suspension with detached
transverse arms lies especially in formation of a virtual steering
axle which, for the most part, can be designed independently of
structural constraints so that favorable axle values such as
camber, axle pin rake, roll radius, and the disturbing-force lever
arm for the driven wheels (dimension a), etc. are adjustable. In
conjunction with the spring system and damping of the motor vehicle
there can be a McPherson strut unit with a telescoping shock
absorber which is coupled in a structurally favorable manner to the
forward lower transverse arm of the wheel suspension by way of a
rubber-metal sleeve bearing.
[0003] The object of the invention is to propose a wheel suspension
of the generic type which is further improved with respect to
driving comfort.
[0004] This object is achieved according to the invention with the
characterizing features of claim 1. Advantageous developments of
the invention are described by the dependent claims.
[0005] According to the invention, it is proposed that at least the
front lower transverse arm is arranged such that the coupling point
of the McPherson strut unit on the transverse arm when the wheel is
deflected, viewed in the transverse direction of the vehicle, runs
parallel to the longitudinal axis of the McPherson strut unit. As
has been recognized, with this measure squeezing of the lower
rubber-metal sleeve bearing can be prevented which otherwise occurs
relative to the transverse arm as a result of a tilt of the
McPherson strut unit which changes over the spring path of the
wheel during deflection and rebound. This results in an improved
response behavior in the spring system of the motor vehicle;
stick-slip effects which may occur on the telescoping shock
absorber are eliminated.
[0006] A design of the wheel suspension which is also advantageous
with respect to the other driving properties of the motor vehicle
consists in that the lower forward transverse arm is positioned
essentially in the transverse direction of the motor vehicle and
the rear lower transverse arm is positioned approx. 45.degree. to
the rear tilted inside thereto.
[0007] Furthermore, the body-side bearing points of the lower
transverse arms can be aligned essentially horizontally at the same
height, with which unwanted migration of the indicated lower
bearing point of the McPherson strut unit over the entire spring
path of the wheel suspension is likewise advantageously
avoided.
[0008] In the conventional manner the tilt of the McPherson strut
unit can be approx. 5 to 10 degrees up to the rear and up to the
inside in order to effect easily manageable matching of the
wheel-guiding transverse arms to the McPherson strut unit, in
addition to a structurally favorable arrangement of the McPherson
strut unit.
[0009] In this connection, the horizontal plane defined by the two
lower transverse arms can also be aligned perpendicular to the tilt
of the McPherson strut unit viewed in the transverse direction of
the vehicle by a suitable design of the wheel carrier-side coupling
points.
[0010] Finally, the body-side bearing of the forward lower
transverse arm in the transverse direction of the motor vehicle can
be made stiffer than in the direction of the longitudinal axis of
the McPherson strut unit. This results in an additional improvement
of driving comfort and the damping properties of the wheel
suspension relative to the body of the vehicle without adversely
affecting the guiding properties of the forward transverse arm.
[0011] One embodiment of the invention will be detailed below. The
figures are schematic.
[0012] FIG. 1 shows, with one wheel carrier, two lower, detached
transverse arms, a suggested track rod and a McPherson strut
unit;
[0013] FIG. 2 shows a side view S of FIG. 1 of the wheel
suspension; and
[0014] FIG. 3 shows a top view of the wheel arrangement as shown in
FIGS. 1 and 2.
[0015] FIGS. 1 to 3 show the lower plane of the front left wheel
suspension 10 for motor vehicles, which wheel suspension is
composed essentially of two lower, individual transverse arms 12,
14, one wheel carrier 16, a track rod 18 which is only suggested,
and a McPherson strut unit 20. The direction of travel of the motor
vehicle is indicated by F. The wheel which is not shown is attached
to the wheel flange 22 which is pivoted-mounted in the wheel
carrier 16.
[0016] The transverse arms 12, 14 are separate transverse arms
which are coupled to the body of the motor vehicle which is not
shown (or an auxiliary frame) via angularly movable rubber-metal
sleeve joints 12a, 14a and to the wheel carrier 16 via ball joints
12b, 14b (compare FIG. 2).
[0017] The third wheel guiding element, located in the lower plane
of the wheel suspension 10 is the track rod 18 which is connected
via a ball joint 18a to a steering means of the motor vehicle which
is not shown and also is coupled to one steering arm 16a of the
wheel carrier 16 via a ball joint 18b.
[0018] In the wheel suspension 10 for non-steered wheels of a motor
vehicle, the track rod 18 is coupled to the body as a further
transverse arm.
[0019] The McPherson strut unit 20 is conventionally composed of a
telescoping shock absorber 24 and a helical compression spring or
support spring 26 which coaxially surrounds the shock absorber.
[0020] The piston rod 24a of the shock absorber 24 is coupled via
an absorber bearing which is not shown to a bearing bracket or
directly to the body of the motor vehicle on which the upper end of
the support spring 26 is also supported. The lower end of the
support spring 26 is supported via a spring plate on the absorber
cylinder 24b of the shock absorber 24.
[0021] The absorber cylinder 24b of the shock absorber 24 is
furthermore coupled to the forward transverse arm 12 referred to as
the support rod 12 below via a support part 24c which is made
slightly arc-shaped with a fork-shaped connecting part 24d with
interposition of a rubber-metal sleevejoint 12c in the vicinity of
the wheel carrier 16. The axis of the sleevejoint 12c is aligned
like the pertinent attachment screw 17 in the longitudinal
direction of the motor vehicle.
[0022] On the neck 16b of the wheel carrier 16 which is lengthened
to the top, there are receiving holes for connecting the individual
upper transverse arms (or a suspension arm) of the wheel suspension
10, for the sake of clarity, the individual transverse arms are not
shown and neither are the disk brake means and the wheel of the
wheel suspension 10.
[0023] The forward lower transverse arm or support rod 12 at this
point is arranged such that the coupling point 12c (center point of
the sleeve joint 12c) of the McPherson strut unit 20 on the support
rod 12 when the wheel is deflected (spring path s) viewed in the
transverse direction of the vehicle (compare FIG. 2) runs at least
approximately parallel to the longitudinal axis (dot-dash line 28)
of the McPherson strut unit 20. The longitudinal axis 28 of the
McPherson strut unit 20 therefore changes only little over the
deflection path of the wheel suspension 10 on 28a and does not
cause squeezing of the sleeve joint 12c or unilaterally acting
moments of the support spring 26 on the shock absorber 24.
[0024] For this purpose, the support rod 12, as is to be seen from
FIG. 3, is positioned with a deviation of approx. 4 degrees (angle
a), that is, more or less in the transverse direction of the motor
vehicle (dot-dash line 30), and the rear lower transverse arm is
positioned approx. 45 degrees (angle 3) to the rear tilted inside
thereto.
[0025] Furthermore the body-side bearing points 12a, 14a, and their
rubber-metal sleeve joints 12a, 14a of the lower transverse arms
12, 14 are aligned essentially horizontally at about the same
height.
[0026] The tilt of the McPherson strut unit 20 relative to the
vertical is moreover 5 to 10 degrees up and to the rear and up to
the inside, as is to be seen from FIGS. 2 and 3.
[0027] The two lower transverse arms are arranged skewed to one
another. Their alignment is chosen such that parallel displacement
of the lower rear transverse arm with the wheel-side articulation
point 14b into the articulation point 12b of the support rod with
the latter yields a plane which is almost perpendicular to the
illustrated tilt (approx. 5 degrees) of the McPherson strut unit 20
viewed in the transverse direction of the vehicle 20.
[0028] Finally, the body-side bearing 12a of the forward lower
support rod 12 in the transverse direction 30 of the vehicle is
designed to be stiffer than in the direction of the longitudinal
axis 28 of the McPherson strut unit 20 (that is, in the vertical
axis). These "spread" sleeve bearings are prior art and can have,
for example, material-weakening lobes (in the vertical axis) or
material-strengthening metal inserts (in the transverse axis),
etc., and therefore are not shown.
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