U.S. patent application number 13/592672 was filed with the patent office on 2012-12-20 for frame structure for a motor vehicle.
This patent application is currently assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC. Invention is credited to Ronny BUFE, Stefan GLOGER, Jens HARTMANN, Joachim KOHR, Heinz-Gunter LANG, Hans-Joachim PATSCHICKE, Matthias SCHLELEIN, Matthias SEYFRIED, Ralph STENGER, Dirk STREHL.
Application Number | 20120319433 13/592672 |
Document ID | / |
Family ID | 41111719 |
Filed Date | 2012-12-20 |
United States Patent
Application |
20120319433 |
Kind Code |
A1 |
BUFE; Ronny ; et
al. |
December 20, 2012 |
FRAME STRUCTURE FOR A MOTOR VEHICLE
Abstract
A frame structure is provided for the underbody of a
self-supporting motor vehicle bodywork. The frame structure
includes, but not included with an elongate tunnel and two
sillboards parallel hereto. The sillboards are disposed on both
sides of the tunnel. The frame structure also includes, but is not
limited to a dashboard cowl with closing plate, which is connected
directly to both sillboards and the tunnel, a wheel housing with a
downwardly open main structural arc, the ends whereof are connected
to the underbody, and on its side facing the underbody (e.g., the
vehicle inner side) the main structural arc has a damper receptacle
in its upper area, from which a supporting strut connected to the
underbody projects downward.
Inventors: |
BUFE; Ronny; (Russelsheim,
DE) ; GLOGER; Stefan; (Muhltal, DE) ;
HARTMANN; Jens; (Florsheim, DE) ; SCHLELEIN;
Matthias; (Bodenheim, DE) ; SEYFRIED; Matthias;
(Bodenheim, DE) ; STENGER; Ralph; (Mainhausen,
DE) ; STREHL; Dirk; (Weiterstadt, DE) ; KOHR;
Joachim; (Neustadt, DE) ; LANG; Heinz-Gunter;
(Budenheim, DE) ; PATSCHICKE; Hans-Joachim;
(Buttelborn, DE) |
Assignee: |
GM GLOBAL TECHNOLOGY OPERATIONS
LLC
Detroit
MI
|
Family ID: |
41111719 |
Appl. No.: |
13/592672 |
Filed: |
August 23, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12427507 |
Apr 21, 2009 |
8287035 |
|
|
13592672 |
|
|
|
|
Current U.S.
Class: |
296/204 |
Current CPC
Class: |
B62D 25/2036 20130101;
B62D 25/16 20130101 |
Class at
Publication: |
296/204 |
International
Class: |
B62D 25/20 20060101
B62D025/20 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 24, 2008 |
DE |
10 2008 020 527.3 |
Claims
1. A frame structure for an underbody of a self-supporting motor
vehicle bodywork, comprising an elongate tunnel; at least two
sillboards parallel to the elongate tunnel and disposed on both
sides of the at least two sillboards; a dashboard cowl with a
closing plate that is connected directly to both of the at least
two sillboards and the elongate tunnel; a wheel housing with a
downwardly open main structural arc and ends of the downwardly open
main structural arc connected to the underbody; and a C-column
fastened to the wheel housing and a C-column reinforcement
configured in one piece with a striker reinforcement; wherein on a
side facing the underbody, the downwardly open main structural arc
comprises a damper receptacle in an upper area, from which a
supporting strut connected to the underbody is adapted to project
downward.
2. The frame structure according to claim 1, wherein the C-column
reinforcement comprises tailored welded blanks.
3. The frame structure according to claim 1, wherein the C-column
reinforcement comprises tailored rolled blanks.
4. The frame structure according to claim 1, wherein the C-column
reinforcement comprises a steel patchwork.
5. The frame structure according to claim 1, wherein the dashboard
cowl is adhesively bonded to a front floor made of fiber-reinforced
plastic and located between the elongate tunnel and a
sillboard.
6. The frame structure according to claim 1, further comprising at
least two aluminum compression cast gussets connected to the wheel
housing and a closed profile enclosing a rear floor extension made
of fiber-reinforced plastic.
7. The frame structure according to claim 6, wherein the closed
profile is an octagonal profile.
8. The frame structure according to claim 1, wherein the downwardly
open main structural arc of the wheel housing has a projecting
outer strut on a vehicle outer side, which is connected on one side
to the downwardly open main structural arc, wherein an outer
structural arc has a flange for connection of a side wall outside
the self-supporting motor vehicle bodywork.
9. The frame structure according to claim 8, further comprising
second connecting struts between ends of the outer structural arc
and ends of the downwardly open main structural arc.
10. The frame structure according to claim 1, further comprising a
strut running substantially parallel to the downwardly open main
structural arc on a vehicle outer side of the wheel housing.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional of U.S. application Ser.
No. 12/427,507, filed Apr. 21, 2009, which claims priority to
German Patent Application No. 102008020527.3, filed Apr. 24, 2008,
which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] The invention relates to motor vehicles, in particular
automobiles and the bodywork thereof.
BACKGROUND
[0003] A self-supporting motor vehicle bodywork has an underbody
which terminates the passenger compartment at the bottom, which
underbody is connected to the roof by means of vertical struts,
usually known as A, B, and C columns. The underbody itself has a
plurality of modules, which are conventionally welded together as
sheet metal parts in the course of production. These include, inter
alia, side skirts, seat cross-members, seat supports, and the
tunnel. Located between these modules extending in the longitudinal
direction of the vehicle are floor panels, that is, in the front
bodywork area, i.e. approximately below the front seats, a front
floor on both sides of the tunnel, in the central bodywork area
behind the heel plate the rear floor and in the rear bodywork area
behind the rear axle cross-member the rear floor extension with the
spare wheel well.
[0004] The documents DE 10 2007 056 854.6, DE 10 2007 035 495.0,
and DE 10 2006 052 992.8, still unpublished at the priority date of
this application, describe a frame structure for a motor vehicle, a
wheel housing, or a front floor for a front floor of a motor
vehicle.
[0005] The D-LFT method, also known as direct LFT method, is a
generally known method for plastics processing. LFT stands for
long-fiber-reinforced plastic. In the D-LFT method a matrix of a
thermoplastic material is plasticized in an extruder and blended in
a mixer with shortened-length continuous fibers. The
fiber-containing plasticized material is then pressed (directly)
into shape. The result is a fiber-plastic composite having a
plastic matrix, in which long fibers are embedded. Due to the use
of an extruder, the fiber length can generally be between about 1
mm and about 50 mm.
[0006] It is at least one object of one embodiment of the invention
to provide a self-supporting motor vehicle bodywork having a low
weight. In addition, other objects, desirable features, and
characteristics, will become apparent from the subsequent summary
and detailed description, and the appended claims, taken in
conjunction with the accompanying drawings and this background.
SUMMARY
[0007] A first embodiment of the invention relates to a frame
structure for the underbody of a self-supporting motor vehicle
bodywork, for example, a self-supporting automobile bodywork. This
comprises an elongate tunnel and two sillboards parallel hereto.
The two sillboards are disposed to the left and the right of the
tunnel. Furthermore, the frame structure has a dashboard cowl with
closing plate, which is connected directly to both sillboards and
the tunnel. The frame structure furthermore has a rear and/or front
wheel housing with a downwardly open main structural arc, the ends
whereof are connected to the bodywork floor or underbody. The main
structural arc has approximately the shape of a downwardly open U
and defines an envelope curve for the rear or front wheel to be
surrounded. In this case, on its side facing the underbody,
subsequently also called vehicle inner side, the main structural
arc has a damper receptacle in its upper area, from which a
supporting strut connected to the underbody projects downward. The
supporting strut thus runs on the inner side of the vehicle when
the wheel housing is mounted in the vehicle and serves to better
absorb the forces introduced into the damper receptacle by the
chassis. Two such supporting struts can also be provided for the
symmetric introduction of forces.
[0008] The frame structure is used to receive the floor cladding
and thereby to also receive the front floor. The tunnel of the
frame structure comes to lie centrally in the vehicle in the
longitudinal direction of the vehicle, and the sillboards run
externally on both sides of the tunnel. In the front area of the
front floor, this is bordered by the tunnel, by a sillboard and by
the dashboard cowl. Further back in the longitudinal direction of
the vehicle, the heel plate running transversely to the tunnel is
connected to the tunnel on the one hand and on the other hand to
the sillboards by means of respectively one gusset. As a result,
the front floor is bordered over its entire periphery by the frame
structure. In view of the absence of the vertical offset between
the sillboards and the dashboard cowl usual in the prior art, it is
in this way possible to select a front floor, which is connected to
its bordering frame structure. The front floor can consist of sheet
metal or of plastic. The last-mentioned choice leads to a
considerable saving in weight with the same structural stability in
the event of a frontal or side impact. The static stability and the
fatigue behavior are ensured by the frame structure to the same
extent as in a bodywork according to the prior art. The saving in
weight leads to a lower fuel consumption of the vehicle and
therefore to lower environmental pollution through emissions.
[0009] The wheel housing assigned to the frame structure and also
its subsequently described modifications completely depart from the
known approach to select a wheel housing with closed plates or to
select a plate shell design for this. Rather, while analyzing the
desired functions of the wheel housing, a strut structure was
selected whereby these desired functions are fundamentally ensured
and in addition can be fulfilled even more reliably due to their
precise detection. In addition, the strut structure allows a
considerable saving of material and weight compared with a
conventional shell structure, which is about 50% in the variants
which can be used in practice. The savings of weight and fuel for a
motor vehicle having this wheel housing can be clearly seen.
[0010] The aforesaid C-column is selected alternatively to the
wheel housing or cumulatively hereto. The C-column vehicle region
possesses an inner plate (also called inner side wall) and an outer
plate (also called outer side wall) and an interposed C-column
reinforcement and as is generally usual, serves the purpose of
connecting the substructure to the roof frame. Since the C-column
reinforcement is configured as a striker reinforcement for mounting
a striker of a vehicle pivoting door, on the one hand fewer parts
need to be held in stock in the warehouse and assembled. On the
other hand, assembly steps and therefore costs are saved, as well
as weight due to unessential fastening means such as screws
etc.
[0011] In summary, the above combination of the frame structure
with the wheel housing makes it possible to provide a very light
motor vehicle bodywork with comparable structural stability
compared to a bodywork in sheet metal design.
[0012] In a second embodiment, the dashboard cowl is adhesively
bonded to a front floor made of fiber-reinforced plastic. With
reference to the explanations from the middle paragraph on the
previous page, the front floor can additionally be adhesively
bonded to the tunnel, a heel plate running transversely to the
tunnel, and a sillboard. The front floor of fiber-reinforced
plastic reduces the weight of the bodywork, as explained above. In
this case, as should be expressly emphasized, the saving in weight
is not at the expense of a reduced structural stability in the
event of a frontal or side impact. Furthermore, an underbody
cladding to improve aerodynamic behavior can be eliminated or the
front floor in the underbody cladding itself.
[0013] The front floor is configured to be largely flat since there
is no vertical offset between sillboards and dashboard cowl.
Largely flat is intended to mean here that the said vertical offset
is less than half the sillboard height. The particularly simple
geometry in this respect simplifies the manufacture of the front
floor and its assembly.
[0014] In a further embodiment, the frame structure has a front
floor manufactured at least partially by the D-LFT method. In this
respect, the front floor consists at least partially of a
fiber-reinforced, in particular long-fiber-reinforced plastic.
[0015] The front floor manufactured by the D-LFT method has a lower
weight with only moderately higher costs compared to a conventional
front floor consisting of sheet metal, with the same structural
stability in the event of a frontal or side impact. Conversely this
front floor offers the possibility of more easily satisfying the
increasingly stringent requirements for motor vehicle bodyworks
relating to their structural stability in side or frontal impact
tests (e.g., those according to Euro NCAP). This is achieved with
the same weight, for example, by combining higher-strength steels
in sufficient material thickness with the light front floor
manufactured by the D-LFT method.
[0016] Embodiments of the front floor have a floor panel comprising
glass fibers, carbon fibers, or natural fibers. are provided as
fibers for the front floor. High-strength aramide fibers such as
those used in the safety field can also be used for the front
floor.
[0017] Investigations have shown that in embodiments in which the
average fiber length was between about 20 mm and about 40 mm, the
front floor on the one hand can be produced efficiently by the D
LFT method and on the other hand, a structural stability can be
achieved by means of the fibers which is equally good or better
than that of sheet metal designs. Best results are obtained with
fiber lengths of about 1 inch (25.4 mm). With smaller fiber
lengths, going into the single-digit millimeter range, the
structural reinforcement due to the fibers becomes increasingly
less whereas longer fibers are increasingly difficult to process in
the extruder.
[0018] In a further embodiment, polyamide (PA for short) or
polypropylene (PP for short) are selected as the material. In the
case of polyamide, on account of its good temperature stability it
is possible to pass the bodywork with mounted front floor through a
painting line without this suffering temperature-induced damage. In
this way, established process sequences which have been developed
for the production of sheet metal bodyworks need not be changed.
This avoids additional costs which would otherwise have arisen due
to changing over production sequences. Polypropylene is a cheaper
material than polyamide and, on account of its lower temperature
stability, necessitates installing the front floor after passing
through the painting line. The installation is effected, for
example, by adhesive bonding.
[0019] Further embodiments of the front floor have a fiber fraction
between about 20 wt. % and about 40 wt. %. Good results were
achieved in this respect with PA6.6/GF30 or PP/GF30. The fiber
fraction is a compromise in this case. Below about 20 wt. %, the
stability of the floor panel is unsatisfactory. Above about 40 wt.
% the floor panel is too heavy, and at the same time its
manufacturability deteriorates.
[0020] One embodiment of the frame structure further provides a
front floor which is connected to a seat mounting made of plastic
in a seamless manner. With the thus ensuing one piece configuration
of front floor and seat mounting, assembly steps are eliminated,
which reduces manufacturing costs and shortens manufacturing time.
At the same time, the mounting holes for the seat mounting thus
have a well-defined position with narrow tolerances, which is not
the case with the conventional sheet metal design. This enables
simplified mounting of the vehicle seats. Due to the one-piece
configuration, a functional integration can largely be undertaken
and for example, various fastening elements such as seat supports
etc. can be integrated in the front floor.
[0021] It is also possible to possible to manufacture the seat
mounting together with the floor panel in the D-LFT method and thus
manufacture the floor panel and the seat mounting simply and
inexpensively in one operation.
[0022] In a further embodiment, the dashboard cowl is welded or
punch riveted to the sillboard and/or the tunnel. The connection of
the dashboard cowl to the sillboard and tunnel is therefore made in
a direct manner and via established machining techniques.
[0023] It can further be provided that an extruded profile is
selected as the sillboard. This profile is one-piece and closed and
requires fewer joining operations for its manufacture than the
two-part top hat section with closing plate which is frequently
used.
[0024] In a further embodiment, the frame structure has a steel
having a yield point of at least 500 MPa. In this respect, this
comprises a high- or superhigh-strength steel, which helps to
compensate for the lower structural stability of a front floor
consisting of plastic compared with the prior art.
[0025] Two gussets made of die-cast aluminum can be provided for
the frame structure for connecting the rear floor, each connected
to the heel plate and a sillboard. The gusset manufactured by the
Vakural casting method is weldable and can therefore be connected
to the steel components of the frame structure, for example, by
means of friction welding but also by means of punch riveting.
[0026] Furthermore, an embodiment can be selected in which aluminum
compression cast gussets are provided as gussets and in which the
aluminum compression cast gussets are connected to respectively one
closed profile.
[0027] The two closed profiles then enclose a rear floor extension
made of fiber-reinforced plastic. The closed profile provides the
rear floor extension with an upwardly closed support surface for
support, to which the rear floor can be adhesively bonded. In this
case, a high stiffness is ensured with low material usage. A
polygonal profile, for example, an octagonal profile, can be
selected as the profile.
[0028] In a further embodiment, an inner strut projecting downward
from the main structural arc is provided on the vehicle inner side.
This inner strut together with the supporting strut in the
penultimate paragraph then forms the reinforcement for the lower
region of the C-column. Shape, position, and alignment of inner
strut and supporting strut can then easily be varied thanks to the
simple strut geometry and additionally optimized in order to better
absorb torsion loads.
[0029] Furthermore, an embodiment is provided in which the
projecting inner strut has a bolt, and the bolt can either be
molded on or inner strut and bolt can be in one piece. This bolt
mostly has a horizontally aligned axis and serves as a pivot
bearing for a seat back of the vehicle. The bolt is an integral
part of component of the wheel housing so that its mounting in the
factory is eliminated and the production costs of the vehicle are
reduced.
[0030] In a further embodiment, a first substantially horizontal
connecting strut for connecting the ends of the main structural
arc, the supporting strut, and the projecting inner strut is
provided. The first connecting strut stiffens the aforesaid strut
structure along the subsequent longitudinal direction of the
vehicle and further serves to connect the wheel housing to the rear
frame of the motor vehicle.
[0031] Furthermore, an embodiment can be provided in which the main
structural arc has a perpendicularly aligned flange. The flange
running over the entire length of the main structural arc or
continuous flange defines a boundary between the inner wheel
housing, which faces the bodywork floor or the vehicle inner side
and which has been described previously, and an outer wheel housing
facing the vehicle outer side and which is to be explained
subsequently. The inner and the outer wheel housing then form the
complete wheel housing. Due to the provision of a flange, it is
initially possible to manufacture inner and outer wheel housing
separately, which allows inexpensive manufacture in view of the
dimensions. The flange then allows the subsequent connection of
these two parts and also the connection of the side wall on the
inside. Naturally it is also possible to manufacture a one-piece
wheel housing directly with correspondingly large forming
tools.
[0032] It can further be provided that the main structural arc has
a projecting outer strut on the side of the flange facing away from
the bodywork floor (i.e., on the vehicle outer side, which is
connected on one side to a downwardly open outer structural arc,
and the outer structural arc has a flange for connection of a side
wall outside the motor vehicle). The outer structural arc together
with the outer strut defines a first part of the outer wheel
housing and with its flange or its flange receptacle, serves for
connection of the side wall on the outside. The flange itself need
not form an arc in this case, even if this is possible due to the
position of the flange at the upper end of the wheel housing
opening.
[0033] In a further embodiment, a strut running parallel to the
main structural arc is provided on the side of the wheel housing
facing the vehicle outer side. This strut, which can be connected
on the one hand to the projecting outer strut of the penultimate
paragraph and on the other hand to another outer strut, is usually
disposed in the upper wheel housing area and serves as a flange
support for connecting the C-column.
[0034] It can furthermore be provided that the outer structural arc
is configured in its lower region as a flange support for
connection of a rear light.
[0035] An embodiment is furthermore possible in which second
connecting struts are provided between the ends of the outer
structural arc and the ends of the main structural arc. These
struts are also used to stiffen the wheel housing and for easier
connection to the rear frame.
[0036] As has been explained above, the wheel housing consists of
an inner and an outer wheel housing. According to a further
embodiment, the inner and/or the outer wheel housing or the wheel
housing on the vehicle inner side and/or on the vehicle outer side
are manufactured in one piece from a light metal compression
casting, in particular from an die-cast aluminum. The strut
structure of the wheel housing explained above in combination with
this choice of material leads to a considerable saving in weight of
about 50% (if both halves of the wheel housing consist of die-cast
aluminum) with comparable structural stability compared to a wheel
housing in conventional shell design.
[0037] Naturally it is also possible to combine the strut structure
of the wheel housing explained above with the classical shell
design. For example, a shell-shaped sheet metal structure connected
to the vertical support flange of the main structural arc can be
selected on the vehicle outer side and a strut structure as
explained above on the vehicle inner side. This procedure makes
repair of the wheel housing easier in cases of damage or then makes
conventional panel beating possible.
[0038] The above embodiments substantially describe the wheel
housing in its basic function. The following measures can also be
taken for connection of the wheel housing to the motor vehicle. The
wheel housing can:
have an integrated tank filler neck receptacle, have an integrated
upper rear bench seat mounting, for example in the form of a
projecting bolt, have molded on or integrated fastening means for a
motor vehicle inner lining, a first aid kit and/or a warning
triangle, have molded-on or integrated eyes for tie-down straps
e.g. for securing objects to be transported in the trunk, have an
integrated spring seat for the rear axle, and/or have an integrated
shock absorber receptacle for the rear axle.
[0039] A feature common to these precautions is that they are an
integrated component of the wheel housing. If a wheel housing is
purchased from a supplier, these precautions can be provided
already during manufacture and therefore need no longer be mounted
in the factory so that the automobile company has less assembly
work with lower cots.
[0040] Furthermore, a C-column can be fastened to the wheel
housing, the C-column reinforcement whereof being configured in one
piece with the striker reinforcement.
[0041] The C-column vehicle area has an inner plate (also called
inner side wall), an outer plate (also called outer side wall) and
an interposed C-column reinforcement and serves, as is generally
usual, to connect the substructure to the roof frame. Since the
C-column reinforcement is configured as a striker reinforcement for
mounting a striker of a vehicle pivoting door, on the one hand
fewer parts need to be kept in stock in the warehouse and
integrated. On the other hand, assembly steps and therefore costs
are saved but also weight due to inessential fastening means such
as screws.
[0042] In one embodiment, the C-column reinforcement consists of
tailored welded blanks. A greater material thickness or sheet metal
thickness and optionally a higher material quality is then provided
for the striker reinforcement.
[0043] With the aid of the tailored welded blanks, a C-column
having approximately tailored stiffness properties with limited
weight can then be achieved, which optimally withstands a side
impact, and at the same time taking into account the desired
function of the aforesaid torsion ring, the striker reinforcement
is integrated.
[0044] In a further embodiment of the frame structure, the C-column
consists of tailored rolled blanks. Tailored rolled blanks are
produced by flexible rolling of steel sheets followed by die
bending, welding, and optionally additional profile bending.
Compared to tailored welded blanks, these yield more uniform
transitions in material thickness with reduced costs.
[0045] A further embodiment further provides a C-column of a
patchwork steel sheet. In contrast to a C-column of tailored welded
blanks, in this case not rectangular profiles but profiles having a
largely free contour are welded together with the result that it is
possible to equip the C-column reinforcement locally with a higher
material thickness and thereby optimize with regard to its
stiffness properties.
[0046] A further embodiment of the invention relates to a
self-supporting motor vehicle bodywork having a frame structure
according to one of the above embodiments.
[0047] One embodiment of the invention also relates to a motor
vehicle, in particular an automobile, having a frame structure
according to one of the above embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0048] The present invention will hereinafter be described in
conjunction with the following drawing figures, wherein like
numerals denote like elements, and:
[0049] FIG. 1 shows a frame structure in a perspective side
view;
[0050] FIG. 2 shows a section A-A through FIG. 1;
[0051] FIG. 3 shows an octagonal profile for bordering the rear
floor;
[0052] FIGS. 4a-d show a front floor for mounting in the frame
structure of FIG. 1;
[0053] FIG. 5 shows a first embodiment of a frame structure with
wheel housing;
[0054] FIG. 6 shows the wheel housing from FIG. 5 viewed from the
vehicle inner side;
[0055] FIG. 7 shows the wheel housing from FIG. 5 viewed from the
vehicle outer side;
[0056] FIG. 8 shows an embodiment of the frame structure with wheel
housing and C-column; and
[0057] FIG. 9 shows a reinforcement C-column.
DETAILED DESCRIPTION
[0058] The following detailed description is merely exemplary in
nature and is not intended to limit application and uses.
Furthermore, there is no intention to be bound by any theory
presented in the preceding background and summary or the following
detailed description.
[0059] FIG. 1 shows a self-supporting frame structure 1 for the
underbody of a self-supporting motor vehicle bodywork, which can
initially be seen without a wheel housing for reasons of clarity.
The arrow P in this indicates the vehicle longitudinal direction,
the tip of the arrow pointing toward the front region of the
vehicle.
[0060] The frame structure 1 has an elongate tunnel 2 with two
straight sillboards 3 and 4 parallel thereto. A dashboard cowl 5
with its closing plate 18, cf. FIG. 2, is welded on the one hand
directly to the tunnel 2 and on the other hand directly with the
two sillboards 3 and 4. The tunnel 2 is additionally welded to the
heel plate 6, which runs parallel to the dashboard cowl 5. The
sillboards 3, 4 are connected via a gusset, in the present case a
gusset 10 or 11 of die-cast aluminum, on account of its
weldability. The two openings 7 or 8 intended for the front floor
right or front floor left, respectively thus have a peripheral and
closed edge. It is thus possible to insert into these openings 7
and 8, a front floor consisting of a fiber-reinforced plastic and
adhesively bond its edge to the edge of the opening 7 or 8. The
overall bodywork is particularly light due to this choice.
[0061] The frame structure 1 is visually similar to a truss frame
and has a high-strength steel having a yield point of at least 500
MPa. The rear floor 17 comes to lie in the rear vehicle area behind
the heel plate 6, which is bordered on both sides by an octagonal
profile 9, cf. FIG. 3. The octagonal profile 9 as a closed profile
provides an upwardly closed support surface for a rear floor 17
made of plastic. In this respect, the rear floor 17 can be placed
with its edge on the support surface 12 of the octagonal profile 9
and adhesively bonded to this. The octagonal profile 9 is in each
case welded to a gusset 10 or 11 of die-cast aluminum and thereby
arranged parallel to the sillboards 3 or 4 configured as extruded
profiles.
[0062] FIGS. 4b and 4c each show a front floor 13 with a floor
panel 14 made of a polyamide produced by the D-LFT method. The
floor panel 14 has an approximately rectangular cut and consists of
PA6.6/GF30 having a material thickness of about 3 mm. The seat
mounting 15 is connected seamlessly to the floor panel 14. This was
produced in the same operation with the floor panel and in this
respect also has PA6.6/GF30. For improving the structural stability
in the event of a side or frontal impact, the floor panel 14
further has a metal reinforcement 16 having a thickness of about
0.8 mm disposed on its surface.
[0063] FIG. 4a shows such a metal reinforcements 16, which is
placed on the seat mounting 15 during assembly and is pressed
positively with this or subsequently adhesively bonded. The result
of the assembly is shown in FIG. 4c. The metal reinforcement 16
improves the behavior of the floor panel 14 in the event of a side
or frontal impact. The metal reinforcement 16 can optionally also
be dispensed with.
[0064] The metal reinforcement 16 has fastening elements (e.g.,
mounting holes), for a motor vehicle seat (not shown). Since the
scatters in the dimensions in the case of a one-part configuration
of floor panel 14 and seat mounting 15 are smaller than for the
production of a multipart sheet metal bodywork in which the seat
mountings 15 are located on various components, assembly of the
motor vehicle seats is made easier.
[0065] FIG. 4d shows the underside 19 of a front floor 13. This
diagram shows the honeycomb structure 80 of the seat mounting 15,
whereby material can be saved compared to a solid design and the
structural stability can even be improved for the case of a frontal
or side impact.
[0066] The front floor modules 13 (left or right) manufactured in
the D-LFT method are approximately 50% lighter than conventional
sheet metal modules. Their use is made possible by the frame
structure 1, whose openings 7 or 8 border the modules over their
entire circumference and provide the possibility of firmly adhering
the modules by means of prepared flanges.
[0067] FIG. 5 shows the frame structure 1 from FIG. 1, but now
supplemented by a wheel housing 20, which is connected on the one
hand to the gussets 10, 11 and on the other hand, to the two
octagonal profiles 9.
[0068] FIG. 6 shows a wheel housing 20 in detail and specifically,
viewed from the vehicle inner side or the passenger compartment,
cf. FIG. 5. The wheel housing 20 is manufactured in one piece from
die-cast aluminum. A main structural arc 21 can initially be
identified, which roughly has the shape of an inverted U, with
adjoining damper receptacle 22 in the upper region. In order to be
able to better absorb the forces introduced via the suspension
struts (not shown), supporting struts 23a and 23b project downwards
from the damper receptacle, so that their lower ends can be
connected to the rear frame (not shown) during assembly.
[0069] Furthermore, the wheel housing 20 has an inner strut 24
projecting downwards from the main structural arc 21. The
supporting struts 23a, 23b and the inner strut 24 together form a
reinforcement of the lower part of a C-column not shown here. The
lower ends 25, 26 of the main structural arc 21 and the lower ends
of the supporting struts 23a and 23b as well as the inner strut 24
are connected to a horizontally disposed connecting strut 27. The
connecting strut 27 serves to stiffen the wheel housing 20 and for
connection to the octagonal profile 9, cf. FIG. 5.
[0070] The main structural frame 21 has a perpendicular flange 28
over its entire length. This delimits the part of the wheel housing
20 located in front of the flange 28 from the perspective of the
observer, the inner wheel housing 29, from the outer wheel housing
30, which is located behind the flange 28. The designations
inner/outer wheel housing are accordingly oriented to the mounting
position in the vehicle. If the wheel housing 20 were mounted in
the vehicle, it would accordingly be viewed from the vehicle inner
side in FIG. 1, cf. FIG. 5.
[0071] FIG. 7 shows the wheel housing 20 of FIG. 1 from the
rearward side that is primarily the outer wheel housing 30. A
projecting outer strut 31 can be seen on this vehicle outer side,
which strut is connected at the end to a downwardly open outer
structural arc 32, the outer structural arc 32 having a flange 33
for abutment of a side wall outside the motor vehicle (not shown).
The flange 33 itself is arcuate and runs approximately from Point A
to Point B.
[0072] Starting from the outer strut 31, a strut 34 runs parallel
to the main structural arc 21 as far as another outer strut 35,
which leads from the main structural arc 21 to Point a of the outer
structural arc 32. The strut 34 serves as a flange support for
connection of the C-column. Furthermore, the outer regions of the
outer structural arc 32 or the lower region thereof are or is
configured as a flange support 36 for connection of a rear light.
The ends of outer structural arc 32 and main structural arc 21 are
furthermore connected to one another for stiffening purposes via
second connecting struts 37a, 37b, which run horizontally and form
a closed ring with the connecting strut 27 of the inner wheel
housing 29.
[0073] The wheel housing 20 shown in FIG. 6 and FIG. 7 has a die
cast aluminum having a material thickness, which lies between about
2 mm to about 5 mm variably distributed over the component.
Compared with a wheel housing in shell design having metal sheets
about 1 mm thick, it has an about 55% lower weight for the same
structural stability. Some of the weight saving, for example, is
attributable to the fact that in a shell design, the central
reinforcing plate for the damper receptacle 22 has a sheet metal
having a thickness of about 2.5 mm whereas in the embodiment shown,
for the same or slightly larger material thickness the weight is
lower because of the lower specific weight of the die cast
aluminum. During manufacture the inner wheel housing 29 and the
outer wheel housing 30 were manufactured separately in forming
tools and then joined together on the flange 28. The separate
manufacture is made for cost reasons because the two wheel housing
halves would have required large and therefore expensive forming
tools because of their dimensions. If larger forming tools are
available, the wheel housing 20 can naturally also be produced in a
single operation and also be manufactured in one piece. In both
cases, further measures in the sense of claims 27 to 31, for
example, the bolt 38 for fastening a seat back can also be
integrated, thus saving assembly time in the automobile
factory.
[0074] FIG. 8 shows the frame structure 1 of FIG. 5, supplemented
by C-columns 39 disposed on both sides and each connected to the
wheel housing 20. The C-column 39 has an outer plate, an inner
plate, and an interposed C-column reinforcement 40, wherein only
the outer plate can be seen in FIG. 8.
[0075] FIG. 9 shows the C-column reinforcement 40 in detail. This
has a flange 41 for connection of the inner side wall and a flange
42, which is to be connected to a wheel housing 20. The region 43
has a greater material thickness, which is achieved via the
thickness of the tailored welded blanks. This serves as striker
reinforcement. It can be seen that a striker 44 is firmly screwed
to this by means of two screws 45.
[0076] Although specific embodiments have been described
previously, the person skilled in the art will recognize that the
description of these embodiments is not intended to restrict the
invention in the specified form. The invention should rather
embrace all modifications, equivalents, and alternatives which come
within the scope of protection of the claimed invention. Moreover,
while at least one exemplary embodiment has been presented in the
foregoing summary and detailed description, it should be
appreciated that a vast number of variations exist. It should also
be appreciated that the exemplary embodiment or exemplary
embodiments are only examples, and are not intended to limit the
scope, applicability, or configuration in any way. Rather, the
foregoing summary and detailed description will provide those
skilled in the art with a convenient road map for implementing an
exemplary embodiment, it being understood that various changes may
be made in the function and arrangement of elements described in an
exemplary embodiment without departing from the scope as set forth
in the appended claims and their legal equivalents.
* * * * *