DAMPING FLUID DEVICES, SYSTEMS AND METHODS
CROSS-REFERENCE
[0001] This application claims the benefit of, and incorporates by reference, U.S.
Provisional Patent Application No. 61/908,199 filed on Nov. 25, 2013, and U.S. Provisional
Patent Application No. 61/941,650 filed on February 19, 2014.
TECHNICAL FIELD
[0002] The subject matter disclosed herein relates to devices, systems, and methods for
reducing and controlling gross vehicle cab vibrations. More particularly, the subject matter
disclosed herein relates to devices, systems and methods for reducing and controlling
movement in off-highway cabs, particularly for reducing vibration and increasing highfrequency
isolation in off-highway cabs.
BACKGROUND
[0003] Gross off-highway cab movement and vibration are particularly troublesome in
that they can cause fatigue and wear on the equipment. In cabs of industrial vehicles or
construction equipment, vibrations are particularly problematic in that they create multiple
fatigue and wear points. In addition to the fatigue and wear on the equipment, the same
movement and vibration causes fatigue to the operator and interferes with the operator's
ability to operate the equipment.
[0004] Broadband damping provides damping across a large spectrum of vibrational
frequencies. Narrowband damping provides for a narrow vibrational band and/or only
providing damping at low or high vibrational frequencies. Broadband damping is usually
achieved by using annular damping and a higher viscosity fluid, which results in damping
across a wide range of frequencies. Narrowband damping is usually achieved by using a low
viscosity fluid in a long orifice so that fluid can resonate within the orifice and have a distinct
natural frequency.
[0005] There is a need for an improved device that reduces gross vibration and movement
in off-highway vehicle cabs, yet is durable and/or can be manufactured in a cost-effective
manner.
SUMMARY
[0006] In accordance with this disclosure, improved damping fluid mount devices,
systems and methods are provided, for example with a damping fluid mount and a method or
process for assembling a fluid mount easily adaptable to different static load and damping
fluid mount configurations.
[0007] In one aspect, the present subject matter provides a damping fluid mount, which
includes an inner member, an elastomer section that is affixed to an outer surface of the inner
member, and a cup containing viscous fluid, a crimped portion of the cup being radially
crimped into the elastomer section such that the crimped portion precompresses the elastomer
section and substantially mimics the elastomer contour. The elastomer section has an outer
diameter that is variable along an elastomer contour. The elastomer section may be affixed to
the outer surface of the inner member by being bonded or rigidly affixed thereto. Bonding
may include vulcanization or adhesive bonding.
[0008] In another aspect, a method for assembling a damping fluid mount is provided.
The method includes coupling an elastomer section to an outer surface of an inner member,
inserting the elastomer section coupled to the inner member into a cup, wherein the cup
contains a quantity of viscous fluid, and radially crimping a portion of the cup to form a
crimped portion that extends into an elastomer contour disposed on an exterior surface of the
elastomer section. Crimping the portion of the cup radially precompresses the elastomer
section and decreases an inner diameter of the crimped portion of the cup so that the inner
diameter of the cup substantially mimics the elastomer contour.
[0009] Although some of the aspects of the subject matter disclosed herein have been
stated hereinabove, and which are achieved in whole or in part by the presently disclosed
subject matter, other aspects will become evident as the description proceeds when taken in
connection with the accompanying drawings as best described hereinbelow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 is a perspective view of a damping fluid mount according to an
embodiment of the presently disclosed subject matter.
[0011] Figure 2 is a sectional side view showing a damping fluid mount according to an
embodiment of the presently disclosed subject matter.
[0012] Figure 3 is a top view of a damping fluid mount according to an embodiment of
the presently disclosed subject matter.
[0013] Figure 4 is a side view of a damping fluid mount according to an embodiment of
the presently disclosed subject matter.
[0014] Figure 5 is a sectional side view showing a damping fluid mount according to an
embodiment of the presently disclosed subject matter.
[0015] Figure 6 is a sectional side view showing a damping fluid mount according to an
embodiment of the presently disclosed subject matter.
[0016] Figure 7A is a perspective top view of a mounting plate for a modular top plate
assembly for a damping fluid mount according to an embodiment of the presently disclosed
subject matter.
[0017] Figure 7B is a sectional side view of a mounting plate for a modular top plate
assembly for a damping fluid mount according to an embodiment of the presently disclosed
subject matter.
[0018] Figures 8-10 are sectional views showing in detail a method of assembling a
damping fluid mount according to an embodiment of the presently disclosed subject matter.
[0019] Figure 1 1 illustrates damping test results from the next generation exemplary
damper.
[0020] Figure 12 illustrates comparative test data for high frequency isolation between
the next generation exemplary damper and existing dampers.
[0021] Figure 13 illustrates comparative test data for durability between the next
generation exemplary damper and existing dampers.
DETAILED DESCRIPTION
[0022] The present subject matter provides improvement to vibration damping fluid
mounts for use in off-highway vehicle cabs. The disclosed devices and methods manufacture
a damping fluid mount that eliminates the need for an outer member. Instead, the fluid
damping mount disclosed herein uses a crimped cup design that pre-compresses the elastomer
section of the fluid mount, which provides a fluid mount with superior sealing, improved
fatigue life, increased durability and improved high-frequency isolation.
[0023] In one exemplary configuration shown in Figures 1 and 2, the present subject
matter provides a broadband damping fluid mount 100 contained by a radially crimped cup
200. The broadband damping fluid mount 100 comprises a bonded core that includes an
inner member 110 and an elastomer section 130, where an inner surface of the elastomer
section 130 is coupled to (e.g. bonded, adhered, friction fit, etc.) an outer surface of the inner
member 110.
[0024] An outer surface of the elastomer section 130 comprises an elastomer contour 134
formed with a diameter that varies along a longitudinal axis of the elastomer section 130. In
one aspect, a ring 120 is encapsulated or bonded within the elastomer section 130 and, in
conjunction with the radially precompressed elastomer section 130, increases durability and
damping of the fluid mount 100. In other aspects, the fluid mount 100 does not include the
ring 120. Instead, these embodiments rely substantially on the radial crimp of the cup 200
and the elastomer section 130 to reduce relative motion at the crimped interface.
[0025] In the fluid mount, an upper portion of the inner member 110 includes a blind
threaded hole 112 configured to receive a retaining member 400 (e.g. a bolt as illustrated in
Figure 4), which in some embodiments is used for securing a supporting structure SI (e.g., a
cab of an off-highway vehicle) to the broadband damping fluid mount 100. In one aspect, the
blind threaded hole 112 longitudinally extends from a top surface 116 of the inner member
110 towards a center of the inner member 110, for a specified depth, that varies based on the
length, size and/or shape of the retaining member 400 being used. (See, e.g. Figures 2 and 4).
[0026] The dimensions of the blind threaded hole 112 are selected based on the
parameters of a given application. When blind threaded hole 112 is a through hole and the
fluid mount 100 is sealed, the diameter and/or depth of the blind threaded hole 112 is
selectable so that the volume of air available within the fluid mount 100 can be increased or
decreased. The dimensions of the blind threaded hole 112 are selected during manufacturing.
Alternatively, in some embodiments, the through hole of blind threaded hole 112 includes an
adjustable air volume 116, which, is tuned by adjusting the height of a sealing plug 114.
(See, e.g., Figure 5)
[0027] In addition, in some embodiments, the broadband damping fluid mount 100
comprises a top plate assembly 150 that is interchangeable and modular for use in both roll
over protection structure (ROPS) and non-ROPS applications. In the embodiments shown in
Figures 6, 7A, and 7B, for example, the top plate assembly 150 further comprises a metallic
washer 152, a mounting plate 154, and an elastomeric profile 156 defining an upper snubbing
surface and a radial snubbing surface. As used herein, the term "snubbing" means reducing or
stopping movement between fixed and movable portions of a vehicle (e.g., the frame and the
cab) by absorbing kinetic energy therebetween via an elastomeric profile member of vehicle
mount devices described herein. The profile part can include snubbing surfaces for absorbing
and/or dissipating kinetic energy. Thus, in some aspects "snubbing" is a form of shock
absorbing.
[0028] Figures 7A and 7B are perspective and sectional views, respectively, of the top
plate assembly 150 configured for connection to the broadband damping fluid mount 100.
The top plate assembly 150 as illustrated is modular and includes a mounting plate 154,
which is illustrated as being modular, and an elastomeric profile 156, allowing for gross
motion control to be moved external with respect to the broadband damping fluid mount 100.
That is, gross motion control (e.g., shock absorption) of the vehicle cab with respect to the
frame of the vehicle is limited or reduced via incorporation of an energy absorbing or
dissipating elastomeric profile 156 within the top plate assembly 150. In some aspects, the
elastomeric profile 156 includes an elastomeric material configured to control motion of a
vehicle cab with respect to a vehicle frame via one or more snubbing contact surfaces. In
some aspects, motion controlled snubbing is solely performed by the elastomeric profile 156
of the top plate assembly 150. This allows an easily achievable and readily available method
of changing motion control characteristics of the broadband damping fluid mount 100 in a
modular fashion without changing the low displacement natural frequency of the mount.
[0029] As illustrated by Figure 7B, the elastomeric profile 156 includes a first snubbing
contact surface (downward-facing surface in Figure 7B), a second snubbing contact surface
(upward-facing surface in Figure 7B), and a third snubbing surface that is positioned radiallyinward
on the elastomeric profile 156. Upward and downward snubbing contact surfaces are
adapted to control axial upward and downward motion, and are customizable during
manufacturing for adapting to application needs via altering the contact locations of the
elastomeric profile 156. As used herein, customizable refers to the specific vehicle size,
weight, use and ride characteristics desired by the customer. The top plate assembly 150
also allows the possibility of a modular ROPS plate to be incorporated therein.
[0030] The elastomeric profile 156 includes an annular shaped ring that is symmetric
about a centerline CL of the top plate assembly 150, and it also includes a central aperture
adapted to receive and retain portions of the inner member 110. In some aspects, a portion
of the second snubbing contact surface includes metal, for example, a metallic washer 152
configured to contact portions of the inner member 110 of the broadband damping fluid
mount 100. For example, the metallic washer 152 can contact a surface of the inner member
110 and/or an upper portion of the elastomer section 130 for upward snubbing. This also
provides the added benefit of adjusting the upward snubbing stiffness by simply altering the
outer diameter of metallic washer 152 bonded in elastomeric profile 156 or section.
[0031] Mounting plate 154 of top plate assembly 150 includes at least one mounting
surface and one or more openings or mounting holes provided therein. Mounting plate 154 is
illustrated as a substantially square in shape, but those having skill in the art will recognize
that any of a variety of other shapes are contemplated. Further in this regard, any thickness
of mounting plate 154 is also contemplated. The one or more mounting holes are adapted to
receive one or more retaining for attaching broadband damping fluid mount 100 and/or top
plate assembly 150 to a further support structure (e.g., a supporting frame structure S2, Figure
4) via mounting plate 154. In some aspects, four mounting holes are provided, where each
hole is positioned substantially equidistant from one another at one corner of the mounting
surface of top plate assembly 150. However, any size, shape, and/or quantity of mounting
holes is contemplated.
[0032] In some aspects, interchangeable ROPS and non-ROPS configurations of
mounting plate 154 are used thereby allowing broadband damping fluid mount 100 to
accommodate ROPS and non-ROPS applications. For example, in some embodiments,
mounting plate 154 includes a ROPS plate with an elastomer snubbing section (e.g., an
elastomeric profile 156) bonded thereto for motion control in both the axial and radial
directions. In other embodiments, mounting plate 154 includes a non-ROPS plate with an
elastomer snubbing section bonded thereto. One difference between a ROPS and a non-
ROPS version of mounting plate 154 is that for a non-ROPS version, broadband damping
fluid mount 100 is fit with a thinner, less expensive mounting plate 154. For a ROPS version,
mounting plate 154 is thicker and stronger and includes the ability to carry the required
ROPS loads (See, e.g., Figure 5).
[0033] Likewise, mounting plate 154 and/or elastomeric profile 156 of the top plate
assembly are interchangeable and/or modular for use in ROPS and non-ROPS applications.
In a ROPS version, for example, the load path goes directly from top plate assembly 150,
through inner member 110, to the ROPS-type version of mounting plate 154, and then to a
supporting frame structure S2. This separates the ROPS loading from the static and dynamic
performance features of device 100, allowing the ROPS capability of the mount to be added
or removed by simply changing mounting plate 154 and inner member 110 material of
broadband damping fluid mount 100. This allows the ROPS capability of this mount to be
truly modular by component replacement. Interchangeable top plate assembly 150 comprises
an elastomeric profile 156 having a central aperture therethrough.
[0034] In one aspect, a damping plate 140 is attached at a bottom portion of the inner
member 110. For example, in several embodiments the damping plate 140 is attached to the
bottom portion of the inner member 140 by a radial rivet, a smashing projection, or a bolted
joint, although other such approaches and structures can be sufficient (e.g., Figure 2).
[0035] As shown in Figure 2, a bonded core that includes the inner member 110 and the
elastomer section 130 is snuggly contained within the crimped cup 200 that optionally
includes either one or both of a flange 210 formed on an upper portion of the cup and/or a
substantially flat bottom surface 220. The crimped cup 200 additionally contains a quantity
of viscous fluid 300, which provides damping in the fluid mount 100. For example, when the
bonded core is placed within the cup 200, the quantity of fluid 300 is disposed beneath the
damping plate 140. Thus, the quantity of viscous fluid 300 and the damping plate 140 act as
a dashpot damper by allowing fluid flow around an outer diameter of the damping plate 140
(i.e. annular damping). Where holes (not shown) are included in the damping plate 140, the
damping plate 140 further exhibits orifice damping as the quantity of viscous fluid 300 flows
through the holes in the damping plate 140. In this case, the dashpot damper dissipates the
overall energy of the system and creates softer mount stiffness for equivalent motion control.
In some embodiments, air is present on both sides of the damping plate 140 (i.e., above the
damping plate 140, but below a bottom of the elastomer contour 134, and below the damping
plate 140 in the blind threaded hole 112 of the inner member 110).
[0036] However, increasing the overall damping of a system can result in increased
dynamic stiffness. Therefore, in order to increase overall system damping and maintain
isolation, a low-amplitude decoupler can be used to reduce the damping at low-amplitude,
high frequency input. One means of achieving decoupling is to have the bottom 220 of the
cup be a substantially flat surface. The flat surface provides decreased volume stiffness for
the quantity of viscous fluid 300 disposed below the damping plate 140, thereby providing
improved high-frequency isolation. Alternatively or in addition, the volume of the viscous
fluid 300 is selected so that a certain percentage of air is present in the fluid cavity to allow
deflection even at frequencies at which the damping fluid 300 may get very stiff (such as at
the annular and/or orifice damping interfaces).
[0037] In some embodiments, flange 210 has a square mounting surface 212 for
attachment of the broadband damping fluid mount 100 to supporting frame structure S2.
However, any shape mounting surface will suffice. The flange 210 includes a plurality of
mounting holes 214 disposed on the square mounting surface 212 (e.g. Figures 3 and 4). In
such an embodiment, the flange 210 has four holes 214 at each of the corners of the square
mounting surface 212 of the flange 210; but any combination of mounting surface shape and
number of holes is acceptable.
[0038] Furthermore, the radially crimped cup 200 securely contains the bonded core
within it. Once the bonded core is inserted into the interior of the cup 200, the cup 200 is
radially crimped into the elastomer contour 134 so that the (optional) ring 120 and the bonded
core are crimped inside of the cup 200. In some embodiments, a collet swage machine is
used to radially crimp cup 200, which achieves large deformations in the cup 200 while
minimizing distortion and wall thinning. Alternatively, in other embodiments, hydro-forming
is used to crimp cup 200. Roll forming is another method of crimping cup 200, but it has the
risk of thinning the cup wall and limiting the depth of the allowable deformation in the cup
200.
[0039] Specifically, radially crimping the cup 200 into the elastomer contour 134
improves on other vibration damping fluid mounts. In the embodiments disclosed herein the
need for an outer member is reduced or eliminated since the radially crimped cup 200
performs the same functions as the outer member, while increasing the durability of the
overall fluid mount 100. (See, for e.g. Figure 2).
[0040] Figure 6 is a sectional view of an assembled broadband damping fluid mount 100.
In this configuration, after inserting inner member 110, elastomer section 130, and damping
plate 140 into cup 200 as illustrated in Figure 2, top plate assembly 150 is then provided over
portions of inner member 110, elastomer section 130, and cup 200. Inner member 110 is
received by the central aperture of top plate assembly 150 and retained therein (e.g., Figures
7A and 7B). Metallic washer 152 is configured to physically contact a surface of the inner
member 110 and/or an upper portion of elastomer section 130 for upward snubbing. In some
embodiments, metallic washer 152 further provides stiffness control and an upward snubbing
contact surface. An upward snubbing response can be altered via altering the diameter of
metallic washer 152 bonded to elastomeric profile 156.
[0041] The overall fluid mount 100 has increased durability from radially crimping the
cup 200, since radially crimping the cup 200 both radially precompresses the elastomer
section 130 and radially crimps an inner surface 230 of the crimped cup 200, such that the
elastomer contour 134 and the inner surface 230 of crimped cup 200 have a substantially
similar contour. However, the substantial similarity contours between elastomer contour 134
and the inner surface 230 of crimped cup 200 are not absolutely necessary due to the
incompressible nature of elastomer section 130. The relative motion at the interface between
the elastomer contour 134 and the inner surface 230 of the crimped cup 200 are substantially
minimized. A precompressed friction interface has been previously used for elastomeric
mounts, but precompressed friction interface are not known to be used for elastomeric
mounts used in fluid mounts, as disclosed herein.
[0042] In the embodiment illustrated inner surface 230 of crimped cup 200 stretches
elastomer contour 134 in the axial direction to minimize the relative motion at the interface.
By integrating the ring 120 into the elastomer contour 134 the relative motion at the interface
virtually diminishes, thus providing even more increased durability of the overall fluid mount
100. A second ring (See, e.g., Figure 5) can be added above the elastomer contour 134 and
provide a higher reduction in relative motion.
[0043] Radial precompression of the elastomer section 130 further reduces relative
motion, improves fatigue life, and provides superior sealing of the overall fluid mount 100.
The particular degree of precompression can be designed to provide the desired response in
the elastomer section 130. In some configurations, for example, radial precompression of the
elastomer section 130 ranges from approximately 5% of the original (i.e., uncompressed)
elastomer section wall thickness to approximately 30% of original elastomer section wall
thickness. In some particular examples, the percentage of radial precompression is between
approximately 12% and 20% of the original elastomer wall thickness. Consequently, where
the ring 120 is integrated within the elastomer contour 134, between approximately 12% and
20% radial precompression of the elastomer section 130 results in a significant reduction in
relative motion at the interface, such that the axial position at the interface will not
substantially change over time, which will result in an improved durability resulting from
reduced wear at the interface. That being said, those having skill in the art will recognize that
the amount of precompression is adjustable to adapt fluid mount 100 to different desired
static and/or snubbing load responses. In addition, by selecting the properties of the elastomer
section 130 prior to manufacture, the 1G static load rating of the fluid mount 100 can be
adjusted from its largest load rating to its smallest load rating (e.g., by adjusting the modulus
of the elastomer section 130).
[0044] Further, radial precompression of the elastomer section 130 provides improved
sealing of the viscous fluid 300 inside the fluid mount 100. Traditionally, sealing a specified
volume of viscous fluid within an interior of a fluid mount has been accomplished by using
sealing beads incorporated into the outer contours of the elastomer. Maintaining the specified
volume of viscous fluid within the fluid mount is desirable because of the damping
accomplished by the viscous fluid and the damping plate acting in combination as a dashpot
damper. Even small quantities of leakage of the viscous fluid impacts the efficiency and
ability of the fluid mount to control and reduce gross vehicle cab movement and vibration.
Therefore, radially precompressing the elastomer section 130 provides superior sealing of the
broadband damping fluid mount 100, as disclosed herein, because the elastomer section 130
is compressed to a higher percentage and over a larger area than traditional sealing beads
typically allow. Radial precompression of between about 12% and 30% of the elastomer
section 130 provides effective sealing, although radial precompression substantially between
5% and 30% can also be sufficient. The use of traditional sealing beads incorporated into the
outer elastomer contour 134, in addition to radial precompression of the elastomer 130,
provides for similar results. The radial precompression of the elastomer section 130 provides
sealing even during use in low-temperature environments affecting the different materials'
coefficient of thermal expansion. This approach creates a tight seal over a large area. In
addition, in some embodiments, a vacuum is used during the assembly process to control the
amount of negative or positive pressure in the assembled mount.
[0045] In another aspect, radially crimping the cup 200 provides an additional effect that
has safety benefits. When the cup 200 is radially crimped, the cup 200 has a smaller diameter
at the crimped portion than the outer diameter of the damping plate 140 (e.g. Figure 2). This
acts as a safety precaution by preventing separation of the damping plate 140 from the cup
200, even if elastomeric failure were to occur. Further, the decreased diameter Dl resulting
from radially crimping the cup 200 also operates to react the downward and upward snubbing
loads. The wall of the crimped cup between the original cup diameter DO and the crimped
cup diameter Dl react with the snubbing load transmitted into the precompressed elastomer
section 130 from the inner member 110 and snubbing elements.
[0046] As discussed above, snubbing is an increase in overall mount stiffness caused by
engaging stiffer elements after a certain deflection. In this case, for example, where fluid
mount 100 is secured to a supporting structure SI as shown in Figure 4, after a certain
downward deflection, supporting structure SI engages an upper portion of elastomer section
130, and the downward mount stiffness increases. Similarly, after a certain upward
deflection, the damping plate 140 engages the bottom portion of elastomer section 130 and
the upward mount stiffness increases. In either event, the crimped cup 200 provides a surface
(angled) that reacts the load in each of these upward and downward snubbing portions of the
elastomer 130. Snubbing is beneficial in broadband fluid mounts used in cab mount
applications because it helps to limit overall cab motion.
[0047] Referring to Figure 6, a method of assembly includes a bonded core that includes
an inner member 110, a ring 120, and an elastomer section 130, and a damping plate 140.
The bonded mount is manufactured by adding the inner member and the ring into a mold.
The inner member 110 and ring 120 are provided with proper surface preparation and
adhesive applied. Proper surface preparation is known those skilled in the relevant art. The
mold closes and the elastomer is injected into the cavity and cured, thus curing the elastomer
and adhesive. After the cured mount is removed from the mold, the damping plate 140 is
inserted onto the boss at the bottom of the inner member and the boss is permanently
deformed to retain the damping plate 140. This deformation is accomplished by radial
riveting or orbital riveting, but can also be accomplished with a hydraulic press and either flat
or angled pusher.
[0048] A cup 200 manufactured to the desired tolerances is filled with a specified
quantity of viscous fluid 300 such that the bonded core fits within the cup 200 (e.g. Figures 6
and 7). The cup 200 is then radially crimped into the bonded core so that the elastomer
section 130 and the ring 120 are radially precompressed (e.g. Figure 2) and axially stretched.
The crimp axial length may actually be longer than the axial length of the molded undercut,
thereby axially stretching the elastomer at the interface.
[0049] In one aspect, as shown in Figure 2, the elastomer contour 134 is formed with a
diameter that varies from a point substantially below the square-mounting surface 212 of the
flange 210 to a point on the elastomer contour 134 above the damping plate 140. The
transitions on the elastomer contour 134 from one diameter to another can be substantially
smooth. Therefore, when the cup 200 is crimped into the elastomer contour 134, the cup 200
mimics the elastomer contour 134 and is radially crimped in at least two places, such that a
crimped area is formed that is substantially parallel with the longitudinal axis of the inner
member 110. At the crimped area, the cup 200 has the narrowest diameter (e.g., crimped cup
diameter D l illustrated in Figure 2). Additionally, the cup 200 is crimped to mimic the
elastomer contour 134, such that the external surface 240 of the cup 200 has a smooth
transitional contour from the non-crimped areas of the cup 200 to the crimped area of the cup
(and vice versa), in view of the smooth transitional elastomer contour 134. Alternatively, in
some configurations, elastomer contour 134 has a more abrupt transitional profile, and thus
when the cup 200 is crimped to mimic the elastomer contour 134, the external surface 240 of
the cup 200 has a more abrupt transitional contour from the non-crimped areas of the cup 200
to the crimped area of the cup (and vice versa) .
[0050] The present subject matter can be embodied in other forms without departing from
the spirit and essential characteristics thereof. The embodiments described therefore are to be
considered in all respects as illustrative and not restrictive. Although the present subject
matter has been described in terms of certain preferred embodiments, other embodiments that
are apparent to those of ordinary skill in the art are also within the scope of the present
subject matter.
CLAIMS
What is claimed is:
1. A damping fluid mount comprising:
an inner member;
an elastomer section that is affixed to an outer surface of the inner member, wherein
the elastomer section has an outer diameter that is variable along an elastomer contour; and
a cup containing viscous fluid, a crimped portion of the cup being radially crimped
into the elastomer section such that the crimped portion precompresses the elastomer section.
2. The damping fluid mount of claim 1, wherein the elastomer section is bonded to the
outer surface of the inner member.
3. The damping fluid mount of claim 1, wherein the elastomer section is rigidly secured
to the outer surface of the inner member.
4. The damping fluid mount of claim 1, wherein the elastomer section comprises an
elastomer material selected to have an elastic modulus corresponding to a desired 1G static
load rating.
5. The damping fluid mount of claim 1, wherein radial precompression of the elastomer
section ranges between about 5% and about 30% of an uncompressed thickness of the
elastomer section.
6. The damping fluid mount of claim 5, wherein radial precompression of the elastomer
section is between about 12% and about 20% of the uncompressed thickness of the elastomer
section.
7. The damping fluid mount of claim 1, wherein the cup contains a ratio of viscous fluid
and air corresponding to a desired load response at expected operating frequencies.
8. The damping fluid mount of claim 1, wherein the cup comprises a substantially flat
bottom surface.
9. The damping fluid mount of claim 1, further comprising an annular damping plate
attached to a bottom portion of the inner member;
wherein an outer diameter of the annular damping plate is greater than an inner
diameter of the crimped portion of the cup.
10. The damping fluid mount of claim 1, further comprising a ring integrated within the
elastomer contour and crimped to conform to the elastomer contour;
wherein a diameter of the ring is greater than an inner diameter of the crimped portion
of the cup.
11. The damping fluid mount of claim 1, wherein the inner member includes a blind hole
that longitudinally extends from a top surface of the inner member to a center of the inner
member.
12. The damping fluid mount of claim 1, wherein the cup comprises a flange with a
substantially square-shaped mounting surface disposed on a top rim of the cup.
13. A method for assembling a damping fluid mount comprising the steps of:
coupling an elastomer section to an outer surface of an inner member;
inserting the elastomer section coupled to the inner member into a cup, wherein the
cup contains a quantity of viscous fluid; and
radially crimping a portion of the cup to form a crimped portion that extends into an
elastomer contour disposed on an exterior surface of the elastomer section, wherein crimping
the portion of the cup radially precompresses the elastomer section and decreases an inner
diameter of the crimped portion of the cup.
14. The method for assembling the damping fluid mount of claim 13, wherein coupling
the elastomer section to the outer surface of the inner member comprises bonding the
elastomer section to the outer surface of the inner member.
15. The method for assembling the damping fluid mount of claim 13, wherein coupling
the elastomer section to the outer surface of the inner member comprises rigidly securing the
elastomer section to the outer surface of the inner member.
16. The method for assembling the damping fluid mount of claim 13, wherein
precompressing the elastomer section provides a precompression having a range between
about 15% and about 25% of an uncompressed thickness of the elastomer section.
17. The method for assembling the damping fluid mount of claim 16, wherein
precompressing the elastomer section provides a radial precompression of the elastomer
section of about 20% of the uncompressed thickness of the elastomer section.
18. The method for assembling the damping fluid mount of claim 13, further comprising
coupling a damping plate to a bottom portion of the inner member prior to inserting the
elastomer section coupled to the inner member into the cup.
19. The method for assembling the damping fluid mount of claim 13, further comprising
integrating a ring into the elastomer contour, wherein a diameter of the ring is greater than the
inner diameter of the crimped portion of the cup.
20. The method for assembling the damping fluid mount of claim 13, further comprising
applying a vacuum during one or more of the steps of inserting the elastomer section coupled
to the inner member into a cup or radially crimping a portion of the cup;
wherein a pressure in the damping fluid mount is controlled to be at a desired value.