U.S. patent application number 10/038161 was filed with the patent office on 2003-11-06 for damping structure.
Invention is credited to Carlstedt, Robert P., Clisch, Richard M., Foster, Steven M., Geib, Eric Stephen, Marcos Munoz, Juan Jose, Shih, Shan, Smith, Mark C., Whitney, Daniel Eugene.
Application Number | 20030205860 10/038161 |
Document ID | / |
Family ID | 29268538 |
Filed Date | 2003-11-06 |
United States Patent
Application |
20030205860 |
Kind Code |
A1 |
Carlstedt, Robert P. ; et
al. |
November 6, 2003 |
DAMPING STRUCTURE
Abstract
A damping structure for providing damping and vibration
attenuation includes an intermediate steel sheet positioned between
an upper steel sheet and a lower steel sheet. The structure is
incorporated as a part of a suspension component. The intermediate
sheet is perforated with a plurality of holes, and a plurality of
elastic strips are positioned between each of the sheets when
assembled. The edges of the sheets are welded, sealing viscous
fluid within the structure. Alternatively, the structure can be
secured by rivets. Compression on the damping structure moves the
fluid through the holes, providing a damping effect.
Inventors: |
Carlstedt, Robert P.;
(Rochester Hills, MI) ; Whitney, Daniel Eugene;
(Arlington, MA) ; Smith, Mark C.; (Troy, MI)
; Geib, Eric Stephen; (Fenton, MI) ; Foster,
Steven M.; (Rochester, MI) ; Clisch, Richard M.;
(Canton, MI) ; Shih, Shan; (Troy, MI) ;
Marcos Munoz, Juan Jose; (Pamplona, ES) |
Correspondence
Address: |
CARLSON, GASKEY & OLDS, P.C.
400 WEST MAPLE ROAD
SUITE 350
BIRMINGHAM
MI
48009
US
|
Family ID: |
29268538 |
Appl. No.: |
10/038161 |
Filed: |
January 3, 2002 |
Current U.S.
Class: |
267/217 |
Current CPC
Class: |
B60G 2206/428 20130101;
B60G 2202/30 20130101; F16F 2224/048 20130101; F16F 13/00 20130101;
B60G 2202/11 20130101; F16F 1/18 20130101 |
Class at
Publication: |
267/217 |
International
Class: |
F16F 007/00 |
Claims
What is claimed is:
1. A method for forming a suspension structure comprising the steps
of: forming a damping structure by forming a plurality of holes in
at least one intermediate sheet, positioning said at least one
intermediate sheet substantially between an upper sheet having an
upper edge and a lower sheet having a lower edge, positioning a
plurality of elastic members substantially between each of said
sheets, dispensing a fluid substantially between each of said
sheets, securing said upper sheet and said lower sheet
substantially proximate to said upper edge and said lower edge to
contain said fluid; and attaching said damping structure into a
suspension component.
2. The method as recited in claim 1 further comprising the step of
shaping said upper sheet, said lower sheet, and said at least one
intermediate sheet to a desired shape, each of said sheets being
substantially shaped such that said sheets substantially interfit
when assembled.
3. The method as recited in claim 1 wherein the step of positioning
said plurality of elastic members further comprises securing each
of said plurality of elastic members to an upper surface of each of
said at least one intermediate sheet and to an upper surface of
said lower sheet.
4. The method as recited in claim 1 wherein the step of positioning
said plurality of elastic members further comprises securing each
of said plurality of elastic members to a lower surface of each of
said at least one intermediate sheet and to a lower surface of said
upper sheet.
5. The method as recited in claim 1 wherein the step of securing
said upper sheet to said lower sheet further includes welding said
upper edge of said upper sheet to said lower edge of said lower
sheet.
6. The method as recited in claim 1 wherein the step of securing
said upper sheet to said lower sheet further includes passing a
plurality of attachments members through a plurality of aligned
holes on said upper sheet and said lower sheet, said fluid being
contained by a continuous elastic strip positioned substantially
between said upper sheet and said lower sheet.
7. The method as recited in claim 6 wherein said plurality of
attachment members are positioned substantially between said
elastic strip and said aligned upper edge and said lower edge.
8. The method as recited in claim 6 wherein said plurality of
attachment members are rivets.
9. The method as recited in claim 1 further comprising the step of
securing and electrically connecting a plurality of piezo-elements
to a spring, said piezo-elements being electrically connected to
said structure, said fluid being reactive to an electrical input
produced by said plurality of piezo-elements by a load applied to
said spring.
10. The method as recited in claim 9 wherein said piezo-elements
apply said electric input to said fluid to substantially alter a
state of said fluid.
11. The method as recited in claim 9 wherein said fluid is
electro-rheological.
12. The method as recited in claim 9 wherein said fluid is
magnetic-rheological.
13. The method as recited in claim 1 further comprising the steps
of securing a plurality of electrical elements to a load carrying
member, said electrical elements being electrically connected to
said structure, and applying a voltage to said electrical elements
to produce an electrical input to substantially alter a state of
said fluid.
14. The method as recited in claim 1 wherein a flow of said fluid
through said plurality of holes provides a damping effect.
15. A vehicle suspension system comprising: at least one suspension
component; and at least one damping structure connected to said
suspension component, each of said plurality of damping structures
including at least one intermediate sheet having a plurality of
holes, said at least one intermediate sheet being positioned
substantially between an upper sheet having an upper edge and a
lower sheet having a lower edge, each of said plurality of damping
structures further including a plurality of elastic members
positioned substantially between each of said sheets, said upper
sheet and said lower sheet being secured substantially proximate to
said upper edge and said lower edge to contain a fluid within each
of said damping structures.
16. The vehicle suspension system as recited in claim 15 wherein
there are a plurality of suspension components and a plurality of
damping structures, each of said plurality damping structures being
positioned substantially between said plurality of suspension
components.
17. The vehicle suspension system as recited in claim 15 wherein
said suspension component is a spring.
18. The vehicle suspension system as recited in claim 15 wherein
said upper sheet, said lower sheet, and said at least one
intermediate sheet are made of steel.
19. The method as recited in claim 15 wherein there are one of said
at least one intermediate sheet.
20. The method as recited in claim 15 wherein said at least one
elastic member is made of rubber.
21. The vehicle suspension system as recited in claim 15 wherein
said plurality of elastic members are positioned on an upper
surface of each of said at least one intermediate sheet and to an
upper surface of said lower sheet.
22. The vehicle suspension system as recited in claim 15 wherein
said plurality of elastic members are positioned on a lower surface
of each of said at least one intermediate sheet and to a lower
surface of said upper sheet.
23. The vehicle suspension system as recited in claim 15 wherein
said upper sheet and said lower sheet are secured by welding.
24. The vehicle suspension system as recited in claim 15 wherein
said upper sheet and said lower sheet are secured by attachment
members.
25. The vehicle suspension system as recited in claim 15 wherein
said vehicle suspension system further includes a plurality of
piezo-elements electrically connected to said damping structure,
said plurality of piezo-elements providing an electrical input to
said damping structure under a load applied to said vehicle
suspension system.
26. The vehicle suspension system as recited in claim 25 wherein
said electrical input substantially change a state of said
fluid.
27. The vehicle suspension system as recited in claim 25 wherein
said fluid is electro-rheological.
28. The vehicle suspension system as recited in claim 25 wherein
said fluid is magnetic-rheological.
29. The vehicle suspension system as recited in claim 15 wherein
said vehicle suspension system further includes a load carrying
member including a plurality of electrical elements, said plurality
of electrical elements being electrically connected to said
structure to provide an electrical input to said structure when a
voltage is applied to said electrical elements to produce said
electrical input to substantially changes a state of said
fluid.
30. A vehicle suspension system comprising: a plurality of springs;
and a plurality of damping structures, each of said plurality of
said damping structures being positioned substantially between each
of said plurality of springs, each of said plurality of damping
structures including at least one intermediate sheet having a
plurality of holes, said at least one intermediate sheet being
positioned substantially between an upper sheet having an upper
edge and a lower sheet having a lower edge, each of said plurality
of damping structures further including a plurality of elastic
members positioned substantially between each of said sheets, said
upper sheet and said lower sheet being secured substantially
proximate to said upper edge and said lower edge to contain a fluid
within each of said damping structures.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to a method for
building a structure for vibration attenuation of structural
elements in a vehicle.
[0002] A suspension system absorbs road shock and other vibrations,
while providing for a smooth and comfortable ride. The suspension
system responds to wheel disturbances and reacts to maintain wheel
contact with the road surface. Damping systems produce opposing
forces which counteract vibrations produced during vehicle
operation.
[0003] Damping forces provided by the suspension system cancel
resonant responses which cause unwanted motion. In the prior art,
fluid filled shock absorbers in the suspension system are used to
counteract these vibrations. As fluid is commonly utilized to
provide damping, the damping force increases approximately
proportionally with the viscosity of the damping fluid. A drawback
to prior damping systems is that these shock absorbers are passive
in nature.
[0004] Hence, there is a need in the art for an improved structure
for vibration attenuation of structural elements in a vehicle.
SUMMARY OF THE INVENTION
[0005] This invention relates to a method for building a structure
for vibration attenuation of structural elements in a vehicle.
[0006] The structure includes an upper sheet, a lower sheet and an
intermediate sheet perforated with a plurality of holes. The
sheets, preferably made of steel, are stamped to a desired shape. A
plurality of elastic strips are positioned such that a layer of
elastic strips are located between each the sheets when assembled.
The sheets are assembled so that the intermediate sheet is
positioned substantially between the upper sheet and the lower
sheet, and viscous fluid is dispersed between each layer. The
sheets are secured, preferably by welding, sealing the viscous
fluid within the structure. Movement of the fluid through the holes
provides vibration attenuation and damping when the structure is
compressed, extended, bent or submitted to vibrations.
[0007] In a second embodiment, a continuous elastic sealing strip
is positioned between and substantially inside the edges of the
upper and lower sheets, but outside the edge of the intermediate
sheet, the sealing strip containing the fluid. The structure is
preferably secured, such as by a plurality of rivets positioned
between the edge of the inner and outer sheet and the sealing
strip.
[0008] In a third embodiment, electro-rheological or
magnetic-rheological fluid is utilized. Piezo-elements positioned
in the suspension system provide an electrical input to the fluid
in the structure to change the state of the fluid and alter the
relative stiffness of the structure in response to a proportional
increase in load.
[0009] Accordingly, the present invention provides a method for
building a structure for vibration attenuation of structural
elements in a vehicle.
[0010] These and other features of the present invention will be
best understood from the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The various features and advantages of the invention will
become apparent to those skilled in the art from the following
detailed description of the currently preferred embodiment. The
drawings that accompany the detailed description can be briefly
described as follows:
[0012] FIG. 1 illustrates a vehicle suspension system including
leaf springs and the structure of the present invention;
[0013] FIG. 2 illustrates a side view of the intermediate sheet,
upper sheet, and lower sheet of the present invention stamped to a
desired shape;
[0014] FIG. 3 illustrates a side view of the intermediate sheet,
upper sheet, and lower sheet of the present invention including a
plurality of elastic strips on the upper surfaces of the
sheets;
[0015] FIG. 4 illustrates a side view of the intermediate sheet,
upper sheet, and lower sheet of the present invention including a
plurality of elastic strips on the lower surfaces of the
sheets;
[0016] FIG. 5 illustrates a side view of the assembled structure of
the present invention;
[0017] FIG. 6 illustrates a side view of a second embodiment of the
present invention which utilizes rivets;
[0018] FIG. 7 illustrates the present invention utilizing
electrical elements; and
[0019] FIG. 8 illustrates a perspective view of the embodiment
illustrated in FIG. 7;
[0020] FIG. 9 illustrates the present invention utilizing
piezo-elements; and
[0021] FIG. 10 illustrates a perspective view of the embodiment
illustrated in FIG. 9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0022] FIG. 1 illustrates a vehicle suspension system 13. The
structure 10 of the present invention is positioned between a
suspension component, such as a leaf spring 11, providing damping
forces and vibration attenuation between two vehicle frame members
15, shown schematically. The structure 10 may also be used in place
of a standard sheet component, such as in a strut tower, in seats,
and in a vehicle a sub-frame.
[0023] As illustrated in FIG. 2, the structure 10 is formed of an
intermediate sheet 12, an upper sheet 18, and a lower sheet 20. It
is preferred that the sheets 12, 18 and 20 be made of steel. The
intermediate sheet 12 is perforated with a plurality of holes 14 at
defined sites and of a defined distribution, and the sheet 12 is
stamped to a desired shape. Excess material is removed from the
intermediate sheet 12 to create an intermediate edge 16. Although
the structure 10 can include any number of intermediate sheets 12,
only one intermediate sheet 12 is described and illustrated.
[0024] The upper sheet 18 and lower sheet 20 are stamped to a
desired shape, sheets 12, 18 and 20 being stamped in shape such the
intermediate sheet 12 will substantially fit between the upper
sheet 18 and lower sheet 20 when assembled to create the structure
10. Excess material is removed from the upper sheet 18 and lower
sheet 20, creating an upper edge 22 and lower edge 24,
respectively, which are finished to form an upper flange 26 and a
lower flange 28, respectively.
[0025] As shown in FIG. 3, a plurality of elastic strips 30,
preferably rubber, are bonded to the sheets 12, 18 and 20 after
stamping so that a layer of elastic strips 30 are positioned
between each of the sheets 12, 18 and 20 when assembled into the
structure 10. The elastic strips 30 are positioned to substantially
extend across the sheets 12, 18 and 20 to and from respective edges
16, 22 and 24. In the embodiment shown in FIG. 3, the plurality of
elastic strips 30 are bonded to the upper surface 32 of the
intermediate sheet 12 and the upper surface 34 of the lower sheet
20, the upper sheet 18 including no elastic strips 30. In another
embodiment, shown in FIG. 4, the plurality of elastic strips 30 are
bonded to the lower surface 36 of the upper sheet 18 and the lower
surface 38 of the intermediate sheet 12, the lower sheet 20
including no elastic strips 30. The elastic strips 30 can also be
bonded in other arrangements, such as only on the intermediate
sheet 12 or alternatively only on the upper sheet 18 and lower
sheet 20.
[0026] For certain stamping technologies, such as hydroforming, it
is preferred to bond the elastic strips 30 to the sheets 12, 18 and
20 prior to stamping. Whether the elastic strips 30 are bonded to
the sheets 12, 18 and 20 before or after stamping is determined by
the shape of the sheets 12, 18 and 20, as well as the final
distribution of the elastic strips 30.
[0027] As further shown in FIGS. 3 and 4, a viscous fluid F is
dispersed on the upper surface 32 of the intermediate sheet 12 and
the upper surface 34 of the lower sheet 20 by a fluid dispenser 17
during assembly.
[0028] When assembled, fluid F is dispersed on the upper surface 34
of the lower sheet 20, and the intermediate sheet 12 is positioned
substantially over the lower sheet 20. Additional fluid F is then
dispersed on the upper surface 32 of the intermediate sheet 12, the
upper sheet 18 being positioned substantially over the intermediate
sheet 12.
[0029] As illustrated in FIG. 5, when assembled, the upper flange
26 of the upper sheet 18 substantially contacts the lower flange 28
of the lower sheet 18. The contacting lower flange 28 and upper
flange 26 are secured, sealing the viscous fluid F within the
structure 10. It is preferred that the flanges 26 and 28 of the
structure 10 be secured by welding, such as seam-welding. The
welding 40 extends substantially around the entire upper edge 22
and lower edge 24 of the structure 10, the intermediate edge 16 of
the intermediate sheet 12 being trapped within the structure 10.
The assembled structure 10 provides vibration attenuation and
damping when it is compressed, extended, bent or submitted to
vibrations as the fluid F passes through the plurality of holes
14.
[0030] FIG. 6 illustrates an alternative embodiment of the present
invention. In this embodiment, the intermediate sheet 12 is
substantially smaller in dimension than the upper sheet 18 and the
lower sheet 20. When the structure 10 is assembled, a continuous
elastic sealing strip 42 is positioned substantially inside the
edges 22 and 24 of the upper sheet 20 and lower sheet 22,
respectively, but outside of the intermediate edge 16 of the
intermediate sheet 12. The sealing strip 42 contains the fluid F in
the structure 110. The upper sheet 18 and lower sheet 20 are
secured together by a plurality of attachment members 48 positioned
substantially outside of the sealing strip 42. The sheets 18 and 20
each include a plurality of holes 46. When the structure 110 is
assembled, the holes 46 in the upper sheet 18 substantially align
with holes 46 in the lower sheet 20 to receive the attachment
members 48, such as rivets. The attachment member 48 maintains
compression force and presses on the sealing strip 42 to contain
the fluid F within the structure 110.
[0031] Further damping can occur by using electro-rheological or
magnetic-rheological fluid F, as illustrated in the vehicle
suspension system 113 shown in FIG. 7. When in the liquid state,
the electro-rheological or magnetic-rheological fluid F is flexible
and soft. Electrical elements 58, such as capacitors or coils, are
located on a load carrying member 60 and connected by a plurality
of lead wires 62, shown in FIG. 8. A control voltage generated by a
power source 64 is applied to the electrical elements 58 to
generate an electric field or a magnetic field, supplying voltage
to the structure 10 by a connecting wire 66. The power source 64 is
either inside the system or outside the system, such as a battery.
The control voltage increase the viscosity of the fluid F,
increasing the relative stiffness of the structure 10.
[0032] Alternatively, as shown in FIG. 9, a vehicle suspension
system 13 uses energy converters 52 to transfer the mechanical
energy into electrical energy to control the viscosity of the
electro-rheological or magnetic-rheological fluid F. When in the
liquid state, the electro-rheological or magnetic-rheological fluid
F is flexible and soft. The converters 52 can be a plurality of
piezo-elements 52 mounted to a charge strip 50 on a load carrying
member 11, such as a leaf spring, to derive the electrical input
which increases the viscosity of the fluid F and the stiffness of
the structure 10. The piezo-elements 52 are connected by a
plurality of lead wires 54. Preferably, the piezo-elements 52 be
bonded or glued to the charge strip 50. An increase in load
deflects and energizes the piezo-elements 52 to produce an
electrical input, supplying voltage to the structure 10 by a
connecting wire 54, as illustrated in FIG. 10. The electrical input
increases the viscosity of the fluid F, increasing the relative
stiffness of the structure 10 and producing damping by the opposing
forces created in the structure 10. The voltage signal is related
to the displacement of the suspension and the piezo-element 52
deflection and provides voltage at desired locations of the
structure 10. The piezo-elements 52 can provide constant voltage to
selected portions of the structure 10, allowing for control over
the feel of the ride.
[0033] There are several advantages to utilizing the structure 10
of the present invention in a vehicle. For one, the structure 10
provides damping and vibration attenuation, reducing vibration and
noise. Additionally, there is more freedom in designing components
for a vehicle.
[0034] The foregoing description is only exemplary of the
principles of the invention. Many modifications and variations of
the present invention are possible in light of the above teachings.
The preferred embodiments of this invention have been disclosed,
however, so that one of ordinary skill in the art would recognize
that certain modifications would come within the scope of this
invention. It is, therefore, to be understood that within the scope
of the appended claims, the invention may be practiced otherwise
than as specially described. For that reason the following claims
should be studied to determine the true scope and content of this
invention.
* * * * *