U.S. patent application number 09/908415 was filed with the patent office on 2002-01-31 for hydraulically damping elastomeric bearing.
Invention is credited to Bik, Robert, Tattermusch, Peter, Zech, Ulrich.
Application Number | 20020011701 09/908415 |
Document ID | / |
Family ID | 7649407 |
Filed Date | 2002-01-31 |
United States Patent
Application |
20020011701 |
Kind Code |
A1 |
Bik, Robert ; et
al. |
January 31, 2002 |
Hydraulically damping elastomeric bearing
Abstract
A hydraulically damping elastomeric bearing suitable for
mountings in a motor vehicle includes an elastic block which is
arranged between an outer sleeve and an inner sleeve coaxial
thereto and which connects these elastically to one another, and at
least two chambers which are filled with a liquid damping medium
and communicate with one another via at least one throttle duct. In
order to improve the damping properties of the elastomeric bearing,
four chambers are provided, which are arranged in one plane, the
four chambers each being arranged in one of four quadrants which
are formed via two intersecting axes arranged in the plane, and
that at least two throttle ducts be provided, via which at least
one chamber which is arranged on a first side of the first axis
communicates with at least one chamber which is arranged on a
second side of the first axis, and via which at least one chamber
which is arranged on a first side of the second axis communicates
with at least one chamber which is arranged on a second side of the
second axis.
Inventors: |
Bik, Robert; (Koengen,
DE) ; Tattermusch, Peter; (Esslingen, DE) ;
Zech, Ulrich; (Magstadt, DE) |
Correspondence
Address: |
KENYON & KENYON
ONE BROADWAY
NEW YORK
NY
10004
US
|
Family ID: |
7649407 |
Appl. No.: |
09/908415 |
Filed: |
July 18, 2001 |
Current U.S.
Class: |
267/140.11 |
Current CPC
Class: |
F16F 13/16 20130101 |
Class at
Publication: |
267/140.11 |
International
Class: |
F16F 009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 19, 2000 |
DE |
100 35 024.0 |
Claims
What is claimed is:
1. A hydraulically damping elastomeric bearing for a mounting of a
motor vehicle, comprising: an outer sleeve; an inner sleeve
arranged coaxially to the outer sleeve; an elastic block arranged
between the outer sleeve and the inner sleeve, the elastic block
elastically connecting the outer sleeve and the inner sleeve; four
chambers arranged in one plane, each chamber being arranged in a
respective one of four quadrants formed by a first axis and a
second axis arranged in the plane and intersecting; and at least
two throttle ducts; wherein, via the at least two throttle ducts,
at least one chamber disposed on a first side of the first axis
communicates with at least one chamber disposed on a second side of
the first axis and at least one chamber disposed on a first side of
the second axis communicates with at least one chamber disposed on
a second side of the second axis.
2. The elastomeric bearing according to claim 1, wherein each
chamber disposed on the first side of the first axis and the first
side of the second axis communicates via a first throttle duct with
a chamber disposed on the first side of the first axis and the
second side of the second axis and communicates via a second
throttle duct with a chamber disposed on the second side of the
first axis and the first side of the second axis.
3. The elastomeric bearing according to claim 2, wherein the first
throttle duct and the second throttle duct have different
throttling resistances.
4. The elastomeric bearing according to claim 1, wherein each
chamber disposed on the first side of the first axis and the first
side of the second axis communicates via one of the throttle ducts
with a chamber disposed on the second side of the first axis and
the second side of the second axis.
5. The elastomeric bearing according to claim 1, wherein the first
axis and the second axis are perpendicular.
6. The elastomeric bearing according to claim 1, wherein the
chambers are arranged mirror-symmetrically with respect to at least
one of the first axis and the second axis.
7. The elastomeric bearing according to claim 1, wherein one of the
first axis and the second axis is arranged coaxially to the inner
sleeve and the outer sleeve.
8. The elastomeric bearing according to claim 1, wherein the
chambers are arranged to extend substantially in a direction of an
angle bisecting line of the respective quadrant.
9. The elastomeric bearing according to claim 1, wherein the inner
sleeve includes at least one axial end portion having an outer
contour, an outer cross-section of the outer contour increasing
radially outwardly.
10. The elastomeric bearing according to claim 9, wherein the outer
contour has a conical configuration.
11. The elastomeric bearing according to claim 9, wherein the outer
contour delimits at least one of the chambers.
12. The elastomeric bearing according to claim 1, wherein at least
one of throttle ducts is formed in at least one of: the inner
sleeve; the elastic block; the outer sleeve; an intermediate sleeve
arranged between the elastic block and one of the inner sleeve and
the outer sleeve; and a molding embedded into the elastic block.
Description
[0001] FIELD OF THE INVENTION
[0002] The present invention relates to a hydraulically damping
elastomeric bearing suitable for mountings in a motor vehicle.
BACKGROUND INFORMATION
[0003] German Published Patent Application No. 198 07 949 describes
an elastomeric bearing, in which an elastic block, for example,
made of an elastic plastic or rubber, is arranged between an outer
sleeve and an inner sleeve coaxial thereto. With the aid of this
block, an elastic connection between the outer sleeve and the inner
sleeve is made, which allows relative movements between the
sleeves. The elastomeric bearing also has two chambers which are
filled with a liquid damping medium and communicate with one
another via a throttle duct. Elastomeric bearings of this type are
used in order to mount a vibrating assembly on a non-vibrating
holding device. The elastomeric bearings serve in this context for
vibration insulation or vibration damping. For example, elastomeric
bearings of this type are used in vehicle construction, in order to
mount vehicle axles, a transmission or an engine on the vehicle
body. In this case, one of the sleeves is connected to the
vibrating assembly, whereas the other sleeve is coupled to the
non-vibrating holding device. The vibrations of the assembly result
in relative movements between the sleeves which reduce the volume
of one chamber and simultaneously increase the volume of the other
chamber. At the same time, the liquid damping medium is exchanged
correspondingly between the chambers via the throttle duct. The
throttling action of the throttle duct results in a damping of the
relative movement and therefore in a damping of the vibrations
capable of being transmitted between the sleeves.
[0004] Conventional elastomeric bearings have a working direction
dependent on the application because of the selected arrangement of
the chambers. Thus, a reduction in volume of one chamber with a
simultaneous increase in volume of the other chamber is possible
only in the case of those relative movements between the sleeves
which have a direction component arranged parallel to the working
direction. A conventional elastomeric bearing can accordingly damp
hydraulically only those loads or vibrations which have a direction
component arranged parallel to the working direction. In some
applications of such elastomeric bearings, particularly in vehicle
construction, however, different loads with different loading
directions may occur. For example, on a vehicle, propulsive forces
and braking forces, impacts and wheel-load changes in different
directions may act on the respective elastomeric bearing.
[0005] It is an object of the present invention to provide an
elastomeric bearing, in which a damping action may be achieved in a
plurality of different directions.
SUMMARY
[0006] The above and other beneficial objects of the present
invention are achieved by providing an elastomeric bearing as
described herein. In one example embodiment of the present
invention, a plurality of chambers are arranged in the elastomeric
bearing and are connected to one another via corresponding throttle
ducts so that two intersecting directions of movement are ensured
and so that relative adjustment between the sleeves reduces the
volume in at least one of the chambers and increases the volume in
another chamber coupled thereto. Vibration damping may thereby be
achieved for all directions of movement which are in a plane
spanned by the intersecting directions of movement or axes.
[0007] According to an example embodiment of the present invention,
each chamber which is arranged on a first side of the first axis
and on a first side of the second axis may communicate, via a first
of the throttle ducts, with a second chamber which is arranged on
the first side of the first axis and on a second side of the second
axis and, via a second of the throttle ducts, with a chamber which
is arranged on a second side of the first axis and on the first
side of the second axis. It is possible, by virtue of this
arrangement of the chambers and throttle ducts, for one and the
same chamber to be capable of being compressed in the two
directions of movement arranged parallel to the axes. Furthermore,
in such an example embodiment, it is possible to provide the first
throttle duct and the second throttle duct with different
throttling resistances, so that the damping action is more
pronounced in the direction of one axis than in the direction of
the other axis.
[0008] In connection with the present invention, the term "on this
side" describes a position on one side, whilst the term "on that
side" denotes a position on the other side.
[0009] According to an example embodiment of the present invention,
one of the axes may be arranged coaxially to the sleeves of the
elastomeric bearing. Axial loads on the elastomeric bearing are
damped correspondingly.
[0010] In another example embodiment of the present invention, the
inner sleeve of the elastomeric bearing may include at least one
axial end portion, the outer contour of which includes an outside
diameter increasing axially outwardly. By virtue of this
arrangement, the inner sleeve may be fastened more effectively to a
component to be connected thereto.
[0011] The outer contour of the axial end portion may delimit at
least one of the chambers, thus resulting in intensive support and
interaction between the respective chamber and the inner
sleeve.
[0012] The features mentioned above and those explained below may
be used not only in the combination specified but also in other
combinations or alone, without departing from the scope of the
present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic longitudinal cross-sectional view of
an example embodiment of an elastomeric bearing according to the
present invention.
[0014] FIG. 2 is a schematic longitudinal cross-sectional view of
another example embodiment of an elastomeric bearing according to
the present invention.
[0015] FIG. 3 is a schematic longitudinal cross-sectional view of
an example embodiment of an elastomeric bearing according to the
present invention taken along the line III-III illustrated in FIGS.
1 and 2.
DETAILED DESCRIPTION
[0016] As illustrated in FIGS. 1 to 3, an elastomeric bearing 1
according to the present invention includes an outer sleeve 2 and,
coaxially thereto, an inner sleeve 3. Arranged radially between the
outer sleeve 2 and the inner sleeve 3 is an elastic block 4 which
connects the two sleeves 2 and 3 elastically to one another. For
example, the block 4 may be vulcanized onto one of the sleeves or
onto both sleeves 2, 3. Furthermore, the elastomeric bearing 1
includes four chambers, 5, 6, 7 and 8 which are filled with a
liquid damping medium. In the example embodiments of the present
invention illustrated, to form the chambers 5, 6, 7, 8,
corresponding recesses are cut out in a region of the block 4 which
faces the inner sleeve 3, so that the chambers 5, 6, 7, 8 are
delimited radially inwardly by the outer face of the inner sleeve 3
and radially outwardly by the block 4.
[0017] As illustrated in FIGS. 1 and 2, the four chambers 5, 6, 7,
8 are arranged in one plane, i.e., in the drawing plane or
sectional plane. A system of coordinates consisting of two axes
which are perpendicular to one another and are designated by X and
Z is arranged in this plane. The Z axis is arranged coaxially and
concentrically to the sleeves 2 and 3. The two axes X and Z form
four quadrants Q1, Q2, Q3 and Q4 in the XZ-plane. One of the
chambers 5 to 8 is arranged in each of these quadrants Q1 to Q4. In
the example embodiment of the present invention illustrated, the
chambers 5 to 8 are arranged mirror symmetrically both with respect
to the Z-axis and with respect to the X-axis. The axes X, Z may
also intersect at an angle different from 90.degree..
[0018] The chambers 5 to 8, in their respective quadrants Q1 to Q4,
are oriented parallel to an angle bisecting line of the respective
quadrant Q1 to Q4. Moreover, the two axial end portions of the
inner sleeve 3 are shaped so that their outer contours 9 and 10
include an outer cross-section increasing axially outwardly. The
outer contours 9 and 10 have, for example, a conical configuration,
a generatrix of the outer contours 9, 10 extending parallel to the
angle bisecting lines of the respectively associated quadrants Q1
to Q4. In particular, these generatrices intersect at the
intersection point of the axes Z and X. By virtue of this shaping
of the inner sleeve 3, the latter possesses, on each of its axial
end portions, a relatively large-area axial end face 11 and 12, via
which a particularly stable support of the inner sleeve 3 on a
component to be mounted may be achieved.
[0019] As illustrated in FIG. 1, four throttle ducts 13, 14, 15, 16
are provided, which connect two adjacent chambers 5 to 8 to one
another. The arrangement of the throttle ducts 13 to 16 is selected
so that the chamber 5 of the first quadrant Q1 communicates via the
first throttle duct 13 with the chamber 8 of the fourth quadrant Q4
and via the second throttle duct 14 with the chamber 6 of the
second quadrant Q2. Correspondingly, the chamber 6 of the second
quadrant Q2 is connected via the second throttle duct 14 to the
chamber 5 of the first quadrant Q1 and via the third throttle duct
15 to the chamber 7 of the third quadrant Q3. The chamber 7 of the
third quadrant Q3 is coupled via the third throttle duct 15 to the
chamber 6 of the second quadrant Q2 and via the fourth throttle
duct 16 to the chamber 8 of the fourth quadrant Q4, whereas the
chamber 8 of the fourth quadrant Q4 communicates via the fourth
throttle duct 16 with the chamber 7 of the third quadrant Q3 and
via the first throttle duct 13 with the chamber 5 of the first
quadrant Q1.
[0020] The elastomeric bearing 1 illustrated in FIG. 1 operates as
follows:
[0021] In the event of a load parallel to the Z-axis, which is
indicated by an arrow 17, for example, the inner sleeve 3 is
adjusted upwardly relative to the outer sleeve 2. At the same time,
the volumes of the chambers 6 and 7 are reduced, whereas the
volumes of the chambers 5 and 8 are simultaneously increased.
Damping medium may flow from the chamber 6 into the chamber 5 via
the second throttle duct 14, whereas damping medium flows from the
chamber 7 into the chamber 8 via the fourth throttle duct 16. By
virtue of the configuration of the throttle ducts 14 and 16, the
exchange of damping medium occurs in a correspondingly throttled or
damped manner, so that the adjusting movement between the inner
sleeve 3 and the outer sleeve 2 is also damped correspondingly.
[0022] In the event of a load on the elastomeric bearing 1 parallel
to the X-axis, which is indicated by an arrow 18, for example, the
volumes of the chambers 5 and 6 are reduced, whereas the volumes of
the chambers 7 and 8 increase simultaneously. The exchange of
damping medium occurs via the first throttle duct 13 and via the
third throttle duct 15. A transmission of force or a transmission
of movement between the two sleeves 2 and 3 is damped
correspondingly as a function of the throttling action of the
throttle ducts 13 and 15. The two axial directions Z and X
represent the main working directions of the elastomeric bearing 1.
Relative adjustments which have both components parallel to the
Z-axis and components parallel to the X-axis are damped
correspondingly. Thus, all forces which act on the elastomeric
bearing 1 or relative movements which occur between the sleeves 2
and 3 are damped as soon as one of the associated direction
components is in the XZ-plane.
[0023] According to an example embodiment of the present invention,
the throttle ducts 14 and 16 active for achieving the damping
action in the direction of the Z-axis may have different throttling
resistances from those of the throttle ducts 13 and 15 active for
achieving damping in the direction of the X-axis. A two-dimensional
damping behavior of the elastomeric bearing 1 suitable for the
respective application can be implemented in this manner.
[0024] As illustrated in FIG. 2, the chambers 5 to 8 may also
communicate with one another via throttle ducts 19 and 20 so that
chambers 5 and 7 or 6 and 8 located diametrically opposite one
another with respect to their quadrants Q1 to Q4 are coupled to one
another.
[0025] The example embodiment of the present invention illustrated
in FIG. 2 operates as follows:
[0026] In the event of a load parallel to the Z-axis in the
direction of the arrow 17, for example, the volumes of the chambers
6 and 7 are reduced, whereas the volumes of the chambers 5 and 8
increase. A compensation of damping medium is possible via the
throttle ducts 19 and 20, damping medium flowing out of the chamber
6 via the throttle duct 19 into the chamber 8, whereas damping
medium flows out of the chamber 7 via the throttle duct 20 into the
chamber 5.
[0027] In the event of a load parallel to the X-axis in the
direction of the arrow 18, for example, the volumes of the chambers
5 and 6 are reduced, whereas the volumes of the chambers 7 and 8
increase. Correspondingly, damping medium flows out of the chamber
5 via the throttle duct 20 into the chamber 7 and from the chamber
6 via the throttle duct 19 into the chamber 8.
[0028] Any loading directions within the XZ-plane are possible, in
order to obtain a damping action.
[0029] In the cross-sectional view illustrated in FIG. 3, the
cross-sectional plane is rotated through 90.degree. with respect to
the Z-axis in relation to the views illustrated in FIGS. 1 and 2.
Accordingly, a Y-axis is arranged in the drawing plane of FIG. 3.
As illustrated in FIG. 3, the chambers 5 to 8 do not extend into
the YZ-plane formed in FIG. 3 by the drawing plane, so that loads
which have only a component parallel to the Y-axis are not damped
hydraulically, but are damped merely as a result of the deformation
of the elastic block 4.
[0030] A load of this type, extending only in the direction of the
X-axis, is indicated in FIG. 3 by an arrow 21.
[0031] It may also be understood from FIG. 3 that the inner sleeve
3 need not have a rotationally symmetrical construction.
[0032] The elastomeric bearing 1 according to the present invention
is also suitable for use as a single-point mounting, in which the
Y-axis serves as the axis of rotation. Because the chambers 5 to 8
may communicate with one another, as illustrated in FIG. 1,
rotational adjustment between the sleeves 2 and 3 about the Y-axis
may also result in a hydraulically damped change in volume in the
chambers 5 to 8. In such an application, a sufficient damping
action may be achieved.
[0033] Such rotational adjustment is indicated in FIG. 3 by a
curved double arrow 22.
[0034] The throttle ducts 13, 14, 15, 16 (FIG. 1) and 19, 20 (FIG.
2) are illustrated merely schematically by broken lines, in order
to explain the coupling of the individual chambers 5, 6, 7, 8. The
throttle ducts 13, 14, 15, 16 and 19, 20 may be implemented in any
other suitable manner. For example, the ducts may be formed in the
inner sleeve 3. The throttle ducts may extend within the block 4.
The throttle ducts may also be formed in the outer sleeve (2).
Furthermore, it is possible to arrange between the block 4 and the
inner sleeve 3 or between the block 4 and the outer sleeve 2 an
intermediate sleeve in which the throttle ducts are formed. The
throttle ducts may be formed in a separate molding which is
produced, for example, from plastic and is embedded into the block
4. The abovementioned alternative configurations of the throttle
ducts may also be combined.
* * * * *