U.S. patent application number 13/873408 was filed with the patent office on 2014-03-06 for laser welded structural fender inner blank for mass optimization.
The applicant listed for this patent is GM GLOBAL TECHNOLOGY OPERATIONS LLC. Invention is credited to Michael J. Green, James M. Townson, Robert G. Watts.
Application Number | 20140062136 13/873408 |
Document ID | / |
Family ID | 50186466 |
Filed Date | 2014-03-06 |
United States Patent
Application |
20140062136 |
Kind Code |
A1 |
Townson; James M. ; et
al. |
March 6, 2014 |
LASER WELDED STRUCTURAL FENDER INNER BLANK FOR MASS
OPTIMIZATION
Abstract
An inner fender panel for a structural fender of an automotive
vehicle is disclosed. The panel includes an outer surface
configured for attachment to the inner surface of an outer panel of
the fender and an inner surface; the inner panel comprising a
plurality of abutting inner fender panel sections that are joined
to one another, each inner fender panel section having a thickness,
at least two abutting inner fender panel sections having
thicknesses that are different. A structural fender for an
automotive vehicle is also disclosed. The fender includes a formed
outer panel having a viewable outer surface and an inner surface.
The fender also includes a formed inner fender panel as described
comprising a plurality of abutting inner fender panel sections that
are joined to one another, each inner fender panel section having a
thickness, at least two abutting inner fender panel sections having
thicknesses that are different.
Inventors: |
Townson; James M.;
(Clarkston, MI) ; Green; Michael J.; (Waterford,
MI) ; Watts; Robert G.; (Leonard, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GM GLOBAL TECHNOLOGY OPERATIONS LLC; |
|
|
US |
|
|
Family ID: |
50186466 |
Appl. No.: |
13/873408 |
Filed: |
April 30, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61697755 |
Sep 6, 2012 |
|
|
|
Current U.S.
Class: |
296/191 ; 29/428;
296/193.05 |
Current CPC
Class: |
B23K 26/24 20130101;
B62D 25/163 20130101; B62D 25/085 20130101; B62D 27/02 20130101;
B62D 25/02 20130101; B62D 65/02 20130101; B62D 21/155 20130101;
Y10T 29/49826 20150115; B62D 27/06 20130101 |
Class at
Publication: |
296/191 ;
296/193.05; 29/428 |
International
Class: |
B62D 25/02 20060101
B62D025/02; B62D 65/02 20060101 B62D065/02 |
Claims
1. An inner fender panel for a structural fender of an automotive
vehicle comprising an outer surface configured for attachment to
the inner surface of an outer panel of the structural fender, and
an inner surface; the inner fender panel comprising a plurality of
abutting inner fender panel sections that are joined to one
another, each inner fender panel section having a thickness, at
least two abutting inner fender panel sections having thicknesses
that are different.
2. The inner fender panel for a structural fender of claim 1,
wherein the outer surface is substantially planar.
3. The inner fender panel for a structural fender of claim 1,
wherein the outer surfaces of abutting inner fender panel sections
having thicknesses that are different are substantially
co-planar.
4. The inner fender panel for a structural fender of claim 1,
wherein each of the plurality of abutting inner fender panel
sections comprise a metal sheet material having a material
composition.
5. The inner fender panel for a structural fender of claim 4,
wherein the metal sheet material of each of the plurality of
abutting inner fender panel sections have the same material
composition.
6. The inner fender panel for a structural fender of claim 4,
wherein the metal sheet material of the plurality of abutting inner
fender panel sections have different material compositions.
7. The inner fender panel for a structural fender of claim 4,
wherein the material composition of the metal sheet comprises a
steel alloy or an aluminum alloy.
8. The inner fender panel for a structural fender of claim 1,
wherein the thickness of the inner fender panel sections range from
about 0.75 mm to about 2.5 mm.
9. The inner fender panel for a structural fender of claim 8,
wherein the thickness of the inner fender panel sections range from
about 0.8 mm to about 1.5 mm.
10. The inner fender panel for a structural fender of claim 1,
wherein the abutting inner fender panel sections are joined to one
another by a laser weld joint between them.
11. The inner fender panel for a structural fender of claim 10,
wherein the laser weld joint is configured to extend in a
substantially vertical direction or a substantially axial direction
when the inner fender panel is installed on an automotive
vehicle.
12. The inner fender panel for a structural fender of claim 1,
wherein the a plurality of abutting inner fender panel sections
comprise a door attachment section that abuts a central section
that abuts a front attachment section, and wherein the central
section has a thickness that is less than the door attachment
section and the thickness of the front attachment section.
13. A structural fender for an automotive vehicle, comprising: a
formed outer panel having a viewable outer surface and an inner
surface; and a formed inner fender panel having an outer surface
configured for attachment to the inner surface of the outer panel,
and an inner surface; the inner fender panel comprising a plurality
of abutting inner fender panel sections that are joined to one
another, each inner fender panel section having a thickness, at
least two abutting inner fender panel sections having thicknesses
that are different.
14. The structural fender of claim 13, wherein the outer surfaces
of abutting inner fender panel sections having thicknesses that are
different are substantially co-planar.
15. The structural fender of claim 13, wherein each of the
plurality of abutting inner fender panel sections comprise a metal
sheet material having a material composition and each of the
material compositions are the same.
16. The structural fender of claim 13, wherein the plurality of
abutting inner fender panel sections are joined to one another by
laser weld joints.
17. The structural fender of claim 13, wherein a plurality of
abutting inner fender panel sections comprise a door attachment
section that abuts a central section that abuts a front attachment
section, and wherein the central section has a thickness that is
less than the door attachment section and the thickness of the
front attachment section.
18. The structural fender of claim 13, wherein the structural
fender comprises: a first front fender that is operably attached to
a first end of a cross-car extending positioning and reinforcement
structure having the first end and an opposed second end; and a
second fender that comprises a mirror image of the first front
fender and is attached to the second end of the positioning and
reinforcement structure, wherein the positioning and reinforcement
structure is operable to a predetermined position of the first
front fender and the second fender in relation to a front hood of
the vehicle.
19. A method of making an inner fender panel for a structural
fender comprising an outer surface configured for attachment to the
inner surface of an outer panel of the fender and an inner surface,
the inner fender panel comprising a plurality of abutting inner
fender panel sections that are joined to one another, each inner
fender panel section having a thickness, at least two abutting
inner fender panel sections having thicknesses that are different,
comprising: forming a plurality of flat planar inner section blanks
that are configured to abut one another and define an inner fender
panel precursor, each inner section blank having a blank thickness,
at least two abutting inner section blanks having thicknesses that
are different; joining abutting inner section blanks to form the
inner fender panel precursor; and stamping the inner fender panel
precursor to plastically deform the inner fender panel blanks and
form the inner fender panel.
20. The method of claim 19, wherein forming the inner section
blanks comprises forming a door attachment section blank that abuts
a central section blank that abuts a front attachment section
blank, and wherein the central section blank has a thickness that
is less than the door attachment section blank and the front
attachment section blank, and wherein joining comprises laser
welding abutting blanks to form a laser weld joint between them.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This patent application claims priority to U.S. Provisional
Patent Application Ser. No. 61/697,755, filed Sep. 6, 2012, which
is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The subject invention relates to vehicles, more particularly
to a positioning and reinforcement structure for a vehicle, and
even more particularly to a structural fender having a multi-gage
inner fender panel.
BACKGROUND
[0003] Vehicles, such as automobiles, are assembled by aligning and
fastening numerous components and subassemblies to one another. One
region of the automobile requiring assembly of such components and
subassemblies is a front end region. This portion of the vehicle is
frequently assembled as an assembly or subassembly referred to as a
"front clip." The front clip is commonly defined as the assembly
comprising the portion of the vehicle extending from the A-pillar
(the roof support pillar associated with the front windscreen) to
the most forwardly disposed component, typically a front bumper.
The front clip includes a structural frame, as well as a variety of
vehicle components that collectively form the vehicle body.
[0004] Several efforts to directly or indirectly mount and/or fix
the vehicle body components to each other, as well as to the
vehicle frame, have relied on welded support structures or frames
and machined body mounting locations for the body components. Front
end clips that use welded frames to attach front clip components
are effective, but they generally require very large capital
investments to support automated, high volume mass production.
Frameless approaches for assembly of the front end clip are very
desirable because they have greatly reduced capital requirements,
but have sometimes been subject to undesirably large variations in
alignment and fastening of components to one other. These large
variations may influence the aesthetic appearance of the automobile
to a user by providing non-uniform or undesirably large or small
gaps and spacings between components and may be the cause of
functional deficiencies, such as undesirable large opening/closing
efforts, alignment and mutilation of components due to misalignment
and interference, and non-uniform gaps and spacings, which each may
affect consumer satisfaction.
[0005] Frameless front clip assembly requires the use of structural
fenders as compared to frame-based front end clip construction
where the fender sheet metal may be attached directly to the frame
and the frame provides much of the needed structural strength. One
area of concern in frameless front clip assemblies that use
structural fenders, such as the front end sheet metal of the
floating structure of a full size truck, has been the development
of structural fenders and methods of making and using them so as to
set the structural fender in an optimal position to ensure
predetermined requirements. These requirements include aesthetic
requirements, such as gap, spacing, class A finish and other
aesthetic requirements, as well as structural function
requirements, such as strength and modal frequency response, and
overall vehicle requirements, such as, for example, reduced mass.
Mass reduction of structural fenders, particularly the inner fender
panel has been difficult to achieve due to the structural
requirements of the panel. High load locations, such as the fender
attachment points, require load carrying capacity that determine
the thickness and hence weight of a monolithic metal sheet blank.
The use of blanks having a reduced thickness with the addition of
doubler plates welded at stress concentration locations or beta
patches, adhesive patches adhered to specific locations to increase
the stiffness and frequency response of a panel at specific
locations, for example, require secondary manufacturing operations
to add them. While providing the benefits described, their use has
generally been very limited due to the added labor and material
costs, as well as the weight that they add to the vehicle, thereby
reducing fuel efficiency.
[0006] Accordingly, it is desirable to provide structural fenders,
particularly inner fender panels, which meet the structural
requirements while reducing the overall manufacturing cost and
weight, thereby reducing vehicle cost and increasing vehicle fuel
efficiency.
SUMMARY OF THE INVENTION
[0007] In one exemplary embodiment, an inner fender panel for a
structural fender of an automotive vehicle comprising an outer
surface configured for attachment to the inner surface of an outer
panel of the fender and an inner surface; the inner fender panel
comprising a plurality of abutting inner fender panel sections that
are joined to one another, each inner fender panel section having a
thickness, at least two abutting inner fender panel sections having
thicknesses that are different is disclosed.
[0008] In another exemplary embodiment, a structural fender for an
automotive vehicle is disclosed. The structural fender includes a
formed outer panel having a viewable outer surface and an inner
surface. The fender also includes a formed inner fender panel
having an outer surface configured for attachment to the inner
surface of the outer panel and an inner surface; the inner fender
panel comprising a plurality of abutting inner fender panel
sections that are joined to one another, each inner fender panel
section having a thickness, at least two abutting inner fender
panel sections having thicknesses that are different.
[0009] In yet another exemplary embodiment, a method of making an
inner fender panel for a structural fender is disclosed. The inner
fender panel includes an outer surface configured for attachment to
the inner surface of an outer panel of the fender and an inner
surface, the inner fender panel comprising a plurality of abutting
inner fender panel sections that are joined to one another, each
inner fender panel section having a thickness, at least two
abutting inner fender panel sections having thicknesses that are
different. The method includes forming a plurality of flat planar
inner section blanks that are configured to abut one another and
define an inner fender panel precursor, each inner section blank
having a blank thickness, at least two abutting inner section
blanks having thicknesses that are different. The method also
includes joining abutting inner section blanks to form the inner
fender panel precursor. The method further includes stamping the
inner fender panel precursor to plastically deform the inner fender
panel blanks and form the inner fender panel.
[0010] The above features and advantages and other features and
advantages of the invention are readily apparent from the following
detailed description of the invention when taken in connection with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Other features, advantages and details appear, by way of
example only, in the following detailed description of embodiments,
the detailed description referring to the drawings in which:
[0012] FIG. 1 is a simplified, partially disassembled perspective
view of a front end assembly of a vehicle;
[0013] FIG. 2 is a perspective view of a positioning and
reinforcement structure of the front end assembly;
[0014] FIG. 3 is a perspective view of a hood disposed proximate
the positioning and reinforcement structure and fenders;
[0015] FIG. 4 is a perspective view of the hood prior to locating
the hood relative to the positioning and reinforcement structure
and fenders;
[0016] FIG. 5 is a perspective view of a hood disposed proximate
the positioning and reinforcement structure and fenders, wherein
the position of the fenders has been established by the positioning
and reinforcement structure which is being fixedly secured to the
radiator support upon closure of the hood and centering of the
structure and hood relative thereto;
[0017] FIG. 6 is a front plan view of the outer surface of an
embodiment of a multi-gage inner fender panel as disclosed
herein;
[0018] FIG. 7 is a front perspective view of the inner fender panel
of FIG. 6;
[0019] FIG. 8 is a rear perspective view of the inner surface of
the inner fender panel of FIG. 6 and a disassembled rear
perspective view of an embodiment of a structural fender assembly
incorporating the same, including a rear perspective view of the
inner surface of an embodiment of an outer fender panel;
[0020] FIG. 9 is an assembled rear perspective view of the
structural fender assembly of FIG. 8;
[0021] FIG. 10 is a comparison illustrating the weight savings
achieved using an embodiment of a multi-gage inner fender panel as
disclosed herein versus a monolithic inner fender panel; and
[0022] FIG. 11 is a flowchart of an embodiment of a method of
making an inner fender panel as disclosed herein.
DESCRIPTION OF THE EMBODIMENTS
[0023] The following description is merely exemplary in nature and
is not intended to limit the present disclosure, its application or
uses. It should be understood that throughout the drawings,
corresponding reference numerals indicate like or corresponding
parts and features.
[0024] In accordance with an exemplary embodiment the gage
optimization of a structure supporting fender inner fender panel of
an automotive vehicle by forming gage optimized, multiple
thickness, laser-welded, sheet metal blanks is disclosed. Using
laser-welded blanks to form the fender inner fender panel provides
mass and cost reduction for the automotive vehicle while
maintaining efficiency of material utilization and structural
performance. The fender inner fender panel may also be attached to
a fender outer panel to form a structural fender, or as it may also
be termed a structural fender assembly, for the vehicle as
described herein.
[0025] Referring to FIGS. 1-11, and particularly to FIGS. 1-4, in
accordance with an exemplary embodiment of the invention, a
partially disassembled view of a front end assembly 10 of a vehicle
12 is shown in the form of an automobile. Although the vehicle 12
is illustrated as an automobile, it is to be appreciated that the
embodiments disclosed herein may be employed in combination with
various alternative types of vehicles. With respect to an
automobile, it is to be further appreciated that the specific type
of automobile is irrelevant to carrying out the embodiments
described below. For example, the automobile may include a car,
truck, sport utility vehicle (SUV) or van. The preceding list is
merely illustrative and is not intended to be limiting of the
numerous automobile types that may benefit from the embodiments of
the invention.
[0026] The vehicle 12 includes a frame 14 formed of several
integrally formed or operably coupled components to provide a
structural support configured to directly or indirectly support
components and subassemblies for the vehicle 12. Supported
components and subassemblies include a plurality of body components
and the vehicle 12 is typically referred to as having a
body-on-frame construction, based on the direct or indirect
mounting and fixing of the various components to the frame 14. The
front end assembly 10 is the region of the vehicle 12 that is
defined by a portion of the vehicle 12 extending forward from what
is known conventionally as an "A-pillar" to a forwardmost
component, such as a front bumper 20. The front end assembly 10 may
be interchangeably referred to as a "front clip" of the vehicle
12.
[0027] To facilitate assembly of the front end assembly 10, both
with respect to components in relation to each other as well as to
the frame 14, a positioning and reinforcement structure 30 is
included. The positioning and reinforcement structure 30 generally
refers to a structure configured to provide a foundation for
inter-part dimensional relationships during the assembly process
for all components of the front end assembly 10, thereby
alleviating reliance on individual machined mounting locations. In
one embodiment, the positioning and reinforcement structure 30
comprises a grill opening reinforcement (GOR) structure that acts
to define and reinforce a grill opening. Since the positioning and
reinforcement structure 30 may be formed as an assembly, it may
also be referred to herein as a positioning and reinforcement
structure 30 or a GOR assembly. As will be described in detail
below, the positioning and reinforcement structure 30 includes
locators, fastening features, and other critical dimensional
relationship interfaces of several components and subassemblies.
Such components and subassemblies typically include structural
fenders or fender assemblies 76, 98, headlamps 122, grills 142,
fascias 22, bumpers 20 and bumper attachment features, hoods 118,
hood latches (not shown), hood bumpers 18 and under-hood closeout
panels (not shown), air baffles (not shown) and radiator supports
60, for example. It is to be understood that the preceding list is
merely illustrative of the numerous components and subassemblies
which may be included in the front end assembly 10 and may benefit
from the positioning and reinforcement structure 30. Exemplary
components and subassemblies will be described in detail below. As
used herein, an axial direction 26 refers to a direction that
extends frontward and rearward along a central axis 25 of the
vehicle, a cross-car direction 27 refers to a direction that
extends laterally or across the vehicle and a vertical direction 28
refers to a direction that extends upwardly and downwardly. In one
embodiment, these directions are mutually orthogonal with regard to
one another.
[0028] Referring now to FIGS. 1 and 2, and particularly FIG. 2, the
positioning and reinforcement structure 30 is illustrated in
greater detail. The positioning and reinforcement structure 30
includes a rectilinearly situated geometry defined by a top support
member 32, a bottom support member 34, a first side member 36 and a
second side member 38. The top support member 32 and the bottom
support member 34 each extend relatively horizontally in a
cross-car direction 27 and relatively parallel to each other. The
first side member 36 and the second side member 38 extend
relatively parallel to each other, but in a relatively vertical 28
direction. As may be understood, the positioning and reinforcement
structure 30 is therefore a substantially cross-car extending and
vertically extending structure or frame. The first side member 36
is coupled proximate a first side member top region 40 to the top
support member 32 and to the bottom support member 34 proximate a
first side member bottom region 42. Likewise, the second side
member 38 is coupled proximate a second side member top region 44
to the top support member 32 and to the bottom support member 34
proximate a second side member bottom region 46. The coupling
between the top support member 32, the bottom support member 34,
the first side member 36 and the second side member 38 may be in
the form of an integral formation process so as to form an integral
positioning and reinforcement structure 30, such as by casting,
laser welding or spot welding, for example. Alternatively, an
operable coupling may facilitate the formation of the positioning
and reinforcement structure 30 as an assembly, such as by
mechanical fasteners, for example. Alternatively, an operable
coupling may facilitate the formation of the positioning and
reinforcement structure 30 as an assembly, such as by mechanical
fasteners, for example. The preceding examples of the precise
connections between the top support member 32, the bottom support
member 34, the first side member 36 and the second side member 38
are merely illustrative and numerous alternative coupling
configurations are contemplated. Irrespective of the precise
attachment, the top support member 32, the bottom support member
34, the first side member 36 and the second side member 38 form a
central portion 39 of the positioning and reinforcement structure
30. Furthermore, the above-described components associated with the
positioning and reinforcement structure 30, as well as those
described below, may comprise various materials, such as plastic or
a metal. Additionally, the components may be formed as an over-mold
having more than one material forming one or more of the
components. Such materials may include magnesium, aluminum, and
composites, for example, however, many alternative materials are
contemplated. The positioning and reinforcement structure 30 or GOR
structure may have any suitable size and shape, and may be used,
for example, to define and reinforce a grill opening having any
suitable size and shape.
[0029] The positioning and reinforcement structure 30 also includes
a first brace 50 extending in a relatively diagonal manner from
proximate the first side member bottom region 42 to a relatively
central location along the top support member 32, to which the
first brace 50 is operably coupled. The first brace 50 may be
coupled to the first side member 36 or the bottom support member
34, or both. Similarly, a second brace 52 is included and extends
in a relatively diagonal manner from proximate the second side
member bottom region 46 to the top support member 32, to which the
second brace 52 is attached. The second brace 52 may be coupled to
the second side member 38 or the bottom support member 34, or both.
The first brace 50 and the second brace 52 may be operably coupled
to the top support member 32 in a relatively coaxial manner, such
that the first brace 50 and the second brace 52 mount to a single
location of the top support member 32. The first brace 50 and the
second brace 52, both singularly and in combination, provide
structural support for the overall positioning and reinforcement
structure 30. Additionally, the first brace 50 and/or the second
brace 52 include mounting and locating features corresponding to
components integrated with, or associated with, the positioning and
reinforcement structure 30.
[0030] Referring again to FIG. 2, the positioning and reinforcement
structure 30 includes a first wing structure 70 and a second wing
structure 72, with the first wing structure 70 being detachably
coupled to the first side member 36, while the second wing
structure 72 is detachably coupled to the second side member 38.
The first wing structure 70 includes a first side flange 74
proximate an outermost location of the first wing structure 70 for
fixing the positioning and reinforcement structure 30 to a first
fender assembly. The second wing structure 72 includes a second
side flange 96 proximate an outermost location of the second wing
structure 72 for fixing the positioning and reinforcement structure
30 to a second fender assembly.
[0031] Referring to FIGS. 3-5, as indicated, the positioning and
reinforcement structure 30 is used to establish predetermined
visual modalities by the positioning and attachment of one or more
components of the front end assembly 10, and preferably a plurality
of the components of the front end assembly 10, particularly those
components that are directly visible or viewable, or those
components that are not directly visible, but whose position
directly or indirectly effects the position of components that are
directly visible. The predetermined visual modalities may include
positioning various components with various predetermined gaps and
spacings, including three-dimensional gaps and spacings, and
particularly uniform gaps and spacings, such as by positioning the
structural fender assemblies 76, 98 with regard to the front hood
118.
[0032] Referring again to FIGS. 3-5, in one embodiment, this
includes providing a modality for establishing a predetermined
position for the structural fender assemblies 76, 98, including an
optimal position as described herein, wherein the fender assemblies
76, 98 are each spaced from the front hood 118 with uniform gaps
and spacings, and preferably the same uniform gaps and spacings.
The positioning and reinforcement structure 30 may be used to set
the position of the fender assemblies 76, 98 relative to the hood
118 upon closure of the hood. In one embodiment, for example, the
positioning and reinforcement structure 30 may include a centering
bracket 110 disposed proximate a top side of the top support member
32. The centering bracket 110 is configured to locate a front
region of the hood 118 to the positioning and reinforcement
structure 30 by a locating pin 114 disposed in a predetermined
location on the front portion of the hood 118 that is configured to
engage a centering feature, such as a bore or slot 112 in the
centering bracket 110 and thereby position, such as by centering,
the positioning and reinforcement structure 30 and the fender
assemblies 76, 98, which are attached, respectively, to a first
side flange 74 and a second side flange 96 of the structure upon
positioning of the GOR structure 30 and fender assemblies 76, 98 to
the hood 118 by the closure of the hood 118, the GOR structure 30
may be fixed to a radiator support 60 (FIG. 3) using any suitable
fasteners such as a plurality of threaded fasteners. Further
explanation of the positioning of fender assemblies 76, 98 using
the positioning and reinforcement structure 30 is provided in U.S.
Provisional Patent Applications 61/695,667, filed on Aug. 31, 2012,
and 61/695,695, filed on Aug. 31, 2012, which are assigned to the
same assignee as this application, and which are hereby
incorporated by reference herein in their entirety.
[0033] Referring to FIGS. 6-10, an inner fender panel 200 for a
structural fender assembly 76, 98 of an automotive vehicle 12
includes an outer surface 210 configured for attachment to the
inner surface 320 of an outer fender panel 300 of the fender
assembly and an inner surface 220. The inner fender panel 200 is a
multi-gage inner fender panel comprising a plurality of abutting
inner fender panel sections 230 that are distinguished herein using
a tenths digit 230.1, 230.2, 230.3, etc. that are permanently
joined to one another. Any number of inner fender panel sections
may be used, including 2, 3, 4, 5, etc. sections. Each of the inner
panel sections may include formed ribs 232, pockets 233, corners
234, flanges 235 or tabs 236 and other formed features or
structures that may be used to increase the stiffness of the panel,
or provide a clearance or accommodate another front end component
that is nested within, or positioned by, or attached to the inner
fender panel section 230, or a combination thereof. The inner
fender panel 200 may also include various cutouts 237, holes or
bores 238, slots 239 or other openings used to lower the mass of
the panel, or provide an opening needed for another component
(e.g., an air box or air conduit), or to receive a fastener or a
locating member.
[0034] Each inner fender panel section 230 has a thickness, and the
multi-gage inner fender panels disclosed herein are characterized
by having at least two abutting inner fender panel sections 230
having thicknesses that are different. In one embodiment, only two
abutting inner fender panel sections have different thicknesses. In
other embodiments, more than two panels have thicknesses that are
different. In one embodiment, all of the inner fender panel
sections 230 have different thicknesses.
[0035] In one embodiment, the outer surface 210 of the inner fender
panel 200 that engages the inner surface 320 of the outer fender
panel 300 is substantially planar. That is, even though the inner
fender panel 200 includes a plurality of inner fender panel
sections 230, and outer surface 210 is a surface of complex
curvature, the surface forms a continuous plane, and particularly
does not have stepwise discontinuities at the interfaces between
abutting inner fender panel sections, including those having
different thicknesses. Stated differently, the outer surfaces 210
of abutting inner fender panel sections 230 having thicknesses that
are different are substantially co-planar. In one embodiment, the
thickness of the inner fender panel sections may range from about
0.75 mm to about 2.5 mm, and more particularly may range from about
0.8 mm to about 1.5 mm. These ranges may include the thicknesses of
the formed inner panel sections that may include up to about 16%
plastic strain (deformation), including a reduction in thickness
from the flat planar inner fender panel blanks from which the
formed inner panel sections are made of up to about 16%.
[0036] The inner fender panel 200 may be made from any suitable
material. In one embodiment, each of the plurality of abutting
inner fender panel sections 230 includes a metal sheet material
having a material composition. Any formable metal sheet material
and material composition that meets the structural and performance
requirements of the vehicle, particularly the vehicle fender, may
be used. Suitable material compositions of the metal sheet material
include various steel alloys or aluminum alloys. Other lightweight,
high strength sheet materials may also be used as the metal sheet,
including various magnesium alloys and titanium alloys. In one
embodiment, the metal sheet material of each of the plurality of
abutting inner fender panel sections 230 may have the same material
composition. In another embodiment, the metal sheet material of the
plurality of abutting inner fender panel sections 230 may have
different material compositions.
[0037] The abutting inner fender panel sections 230 may be joined
to one another by any suitable joint or joining method. In one
embodiment, the abutting panel sections are joined to one another
by laser welding to form laser weld joints 240 between them. The
laser weld joints 240 may be configured to extend in a
substantially vertical direction 28 or a substantially axial
direction 26, or a combination thereof, when the inner fender panel
200 is installed on an automotive vehicle 12. In one embodiment,
the laser weld joints 240 may be selected so that they all in
extend in the same direction (e.g., vertically or axially). This
may be advantageous to increase the efficiency or accuracy, or
both, by allowing the laser welding apparatus to index quickly from
the end of one weld pass 242' to the beginning of the pass on the
adjacent blank as shown schematically, for example, in the laser
welded blank of FIG. 10.
[0038] In one embodiment, the plurality of abutting inner fender
panel sections 230 of an inner fender panel 200 for a structural
fender assembly 76, 98 include a door attachment section 250 that
abuts a central section 252 that in turn abuts a front attachment
section 254. The door attachment section located axially rearward
of the other sections on the vehicle and is positioned proximate
the front door structure and configured for attachment to the front
door structure, such as the front door frame. The door attachment
section 250 may be formed as a one-piece door attachment section.
Alternately, the door attachment section 250 may be formed as a
two-piece door attachment section that includes an upper door
attachment member 250.1 and a lower door attachment member 250.2.
The door attachment section 250 defines a portion of the wheel
cutout 253 as does the front attachment section 254. In one
example, the central section 252 has a thickness that is less than
the door attachment section and the front attachment section. This
is because the stress/load-bearing requirements for the central
section are lower than the adjacent sections, as may be understood
from FIG. 9. Thus, the size, shape, location and lesser thickness
of the central section 252 may be selected to accommodate the lower
stresses and loads. Similarly, the size, shape, location and
greater thicknesses of the door attachment section 250 and front
attachment section 254 may be selected to accommodate the lower
stresses and loads.
[0039] In one embodiment, a structural fender or structural fender
assembly 76, 98 for an automotive vehicle 12 includes a formed
outer fender panel 300 having a viewable outer surface 310 and an
inner surface 320. The structural fender assembly 76, 98 also
includes a formed inner fender panel 200 having an outer surface
210 configured for attachment to the inner surface 320 of the outer
panel 300 and an inner surface 220, where the inner fender panel
200 includes a plurality of abutting inner fender panel sections
230 that are joined to one another, with each inner fender panel
section 230 having a thickness, and at least two abutting inner
fender panel sections 230 having thicknesses that are different.
The outer fender panel 300 and inner fender panel 200 may be
attached to one another by any suitable attachments or attachment
methods, including by a plurality of weld joints, such as a
plurality of spot weld joints. The attachment of the outer fender
panel 300 and inner fender panel 200 forms a structural fender
assembly 76, 98 that provides the necessary vehicle structure to
surround and enclose the associated members of the vehicle frame
and front corner, including the various members of the braking
assembly and wheel assembly as are known in the art, without the
need for an attachment to a separate frame for the front clip. The
structural fender assembly 76, 98 may also include additional
braces 410 or struts that may be used to reinforce or strengthen
portions of the assembly, as well as various brackets or braces,
such as door attachment bracket, 412, positioning and reinforcement
attachment bracket 414 and radiator support bracket 416 that may be
used to attach and/or reinforce the structural fender assembly 76,
98 to other concomitant portions of the vehicle 12 structure.
[0040] As shown, for example, in FIGS. 1-5, in one embodiment, a
first front fender assembly 76, 98 is operably attached to a first
end 174 of a cross-car extending positioning and reinforcement
structure 30 having the first end 174, such as first side flange
74, and an opposed second end 196, such as second side flange 96. A
second front fender 98 that comprises a mirror image of the first
front fender 76 is attached to the second end 196 of the
positioning and reinforcement structure 30, wherein the positioning
and reinforcement structure is operable to fix a predetermined
position of the first fender and the second fender in relation to a
hood 118 of the vehicle 12.
[0041] Referring to FIGS. 10-11, a method 500 of making an inner
fender panel 200 for a structural fender assembly 76, 98 comprising
an outer surface 210 configured for attachment to the inner surface
320 of an outer fender panel 300 of the fender and an inner surface
220, where the inner fender panel 200 comprises a plurality of
abutting inner fender panel sections 230 that are joined to one
another, each inner fender panel section 230 having a thickness,
and at least two abutting inner fender panel sections having
thicknesses that are different, includes the following. The method
500 includes forming 510 a plurality of flat planar inner section
blanks 230' that are configured to abut one another and define an
inner fender panel precursor 200', wherein each inner section blank
230' has a blank thickness, and at least two abutting inner section
blanks 230' have thicknesses that are different. In the example of
FIG. 10, forming includes stamping four flat inner section blanks
230', including blanks 230.1', 230.2', 230.3.degree. and
230.4.degree. having the shapes indicated. These blanks can be cut
from different width rolls of sheet stock as shown in FIG. 10 that
are selected based on the blank sizes to improve the utilization of
the sheet stock and reduce waste and the associated cost. In one
embodiment, forming 510 the inner section blanks 230' comprises
forming a door attachment section blank 250' (that may be formed as
two separate blanks that are joined together) that abuts a central
section blank 252' that abuts a front attachment section blank
254', and wherein the central section blank 252' has a thickness
that is less than the door attachment section blank 250' and the
front attachment section blank 254', and wherein joining comprises
laser welding abutting blanks to form a laser weld joint 240'
between them. The method 500 may also include performing a stress
concentration analysis to determine the stress carrying
requirements, which also may be used to determine the desired
thickness, of the panel sections 230 based upon a predetermined
stress profile in a monolithic inner panel 199 having a
predetermined thickness.
[0042] The method 500 also includes joining 520 abutting inner
section blanks 230' to form the inner fender panel precursor 200',
such as by welding, including welding according to welding path
242. This may include a welding path 242 that forms the weld joints
240' by translating the laser back and forth during welding in a
single welding direction, or more than one welding direction as is
shown in FIG. 10.
[0043] The method further includes stamping 530 the inner fender
panel precursor 200', once the inner section blanks 230' have been
welded together to form the inner fender panel precursor 200', to
plastically deform it and the inner fender panel blanks 230' and
form the inner fender panel 200. Stamping may be performed using
conventional methods for stamping metal sheet, such as progressive
stamping.
[0044] A method 500 of making a fender inner panel by forming gage
optimized, multiple thickness, laser-welded, sheet metal blanks is
disclosed. The structural fenders described herein are made by
discrete placement and laser welding of thin gage sheet metal
pieces of different thicknesses in areas where typical load paths
do not require thicker material. The method includes performing a
load path analysis of the inner fender panel of a structural fender
using multi-gage sheet metal stampings. Forces and load paths are
analyzed for optimum gage reduction of the sheet metal while
maintaining strength where stress concentrations occur. The method
also includes performing a formability and draw stretch thinning
analysis of structural fender using a multi-gage sheet metal blank.
Formability, seam-weld line placement and coil steel usage
efficiency, are balanced within the stamping process. The method
further includes performing a full body modal frequency effect of a
multi-gage structural fender assembly that includes the multi-gage
fender inner fender panel and the fender outer panel. Vehicle modal
frequency improvements are also evaluated by eliminating
non-structural mass. The method further includes blank utilization
for optimization of coil fed trim to length sheet metal. Still
further, the method includes assessment of blank to blank weld seam
placement for stretch form, trim, and piercing operations. This may
be used in some embodiments to avoid placing weld seams in heavily
deformed areas of the blank, as well as avoiding placing weld seams
that intersect cutouts, holes and other features. Usage of a laser
welded blank provides opportunity for mass and cost reduction while
maintaining efficiency of material utilization and structural
performance. Yet further, the method includes incorporation of
blank locating features to ensure weld seam placement during
forming.
[0045] While the invention has been described with reference to
exemplary embodiments, it will be understood by those skilled in
the art that various changes may be made and equivalents may be
substituted for elements thereof without departing from the scope
of the invention. In addition, many modifications may be made to
adapt a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiments disclosed, but that the invention will
include all embodiments falling within the scope of the
application.
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