U.S. patent application number 12/033159 was filed with the patent office on 2008-07-24 for process for in-molding an energy-absorbing countermeasure to a headliner.
This patent application is currently assigned to OAKWOOD ENERGY MANAGEMENT, INC.. Invention is credited to Matthew J. Boucher, Paul E. Cole, Joel Matthew Cormier, Spencer C. Ledford, Michael E. Melinn, Donald Scott Smith.
Application Number | 20080174152 12/033159 |
Document ID | / |
Family ID | 36741064 |
Filed Date | 2008-07-24 |
United States Patent
Application |
20080174152 |
Kind Code |
A1 |
Cormier; Joel Matthew ; et
al. |
July 24, 2008 |
Process For In-Molding An Energy-Absorbing Countermeasure To A
Headliner
Abstract
A process for in-molding an energy-absorbing countermeasure to a
headliner 18 for use in a vehicle. The process includes the steps
of (1) preparing a sheet; (1A) optionally affixing to the sheet a
means for adhering to form a composite sheet; (2) thermoforming the
composite sheet into a composite energy-absorbing countermeasure;
(3) preparing a headliner layup (including optionally a means for
adhering, a headliner core, and a cover stock) before forming a
bond between the headliner layup and the composite energy-absorbing
countermeasure. The assembly thus includes the energy-absorbing
countermeasure 22 and a means for adhering it to the headliner core
18.
Inventors: |
Cormier; Joel Matthew;
(Lathrup Village, MI) ; Smith; Donald Scott;
(Commerce Township, MI) ; Melinn; Michael E.;
(Jenison, MI) ; Cole; Paul E.; (Canadian Lakes,
MI) ; Boucher; Matthew J.; (Rockford, MI) ;
Ledford; Spencer C.; (Zeeland, MI) |
Correspondence
Address: |
BROOKS KUSHMAN P.C.
1000 TOWN CENTER, TWENTY-SECOND FLOOR
SOUTHFIELD
MI
48075
US
|
Assignee: |
OAKWOOD ENERGY MANAGEMENT,
INC.
Dearborn
MI
|
Family ID: |
36741064 |
Appl. No.: |
12/033159 |
Filed: |
February 19, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11044573 |
Jan 27, 2005 |
7384095 |
|
|
12033159 |
|
|
|
|
Current U.S.
Class: |
296/214 |
Current CPC
Class: |
B29C 2791/006 20130101;
B32B 2307/56 20130101; B60R 2019/1846 20130101; B60R 19/18
20130101; F16F 7/121 20130101; B29L 2031/721 20130101; B32B
2605/003 20130101; B32B 27/06 20130101; B32B 7/12 20130101; B60R
2013/0287 20130101; B60R 21/0428 20130101; B60R 21/04 20130101;
B60R 2021/0442 20130101; A62B 1/22 20130101; B29L 2031/3044
20130101; B60N 2/4249 20130101; B29C 51/12 20130101; B29C 51/10
20130101; B60N 2/70 20130101; B60R 2021/0435 20130101; B60R 19/34
20130101; B65D 81/127 20130101; B29C 51/14 20130101; B60R 2021/0414
20130101; F16F 1/376 20130101; B29C 2791/007 20130101; B29L 2009/00
20130101; B60R 13/0225 20130101; B32B 3/28 20130101; B60R 2019/1866
20130101 |
Class at
Publication: |
296/214 |
International
Class: |
B62D 25/06 20060101
B62D025/06 |
Claims
1. A process for attaching an energy-absorbing countermeasure to a
headliner for use in a vehicle, comprising the steps of: (1)
preparing a sheet from which the energy-absorbing countermeasure is
made; (1A) optionally affixing to the sheet a first means for
adhering that has a lower melting temperature than the sheet to
form a composite sheet; (2) thermoforming the composite sheet into
a composite energy-absorbing countermeasure; and (3) optionally
affixing to the headliner layup a second means for adhering and
heating a headliner layup to an optimum temperature to form a bond
between the headliner layup and the composite energy-absorbing
countermeasure, the headliner layup including a headliner core and
a cover stock.
2. The process of claim 1, further comprising the step of: (4)
trimming an untrimmed energy-absorbing countermeasure headliner
assembly.
3. The process of claim 1, wherein the step of heating the
composite sheet and the means for adhering comprise heating the
composite sheet and the means for adhering to a temperature of
about 320.degree. F.
4. The process of claim 1, wherein the step of forming a bond
between the headliner layup and the composite energy-absorbing
countermeasure comprises providing a means for adhering that
includes an adhering means selected from the group consisting of a
polymer film, a laminated polymer film, a co-extruded polymer film,
a roll-coated polymer film, and a spray-coated polymer film.
5. The process of claim 1, wherein step (3) comprises providing a
headliner forming tool that is shaped and has a topography that
defines an assembly of the energy-absorbing countermeasure and the
headliner.
6. The process of claim 1, wherein the optimum temperature in the
heating step comprises heating the headliner layup to a temperature
of about 375.degree. F.
7. A process for attaching an energy-absorbing countermeasure to a
headliner for use in a vehicle, comprising the steps of: (1)
preparing a sheet from which the energy-absorbing countermeasure is
made; (1A) affixing to the sheet a first means for adhering that
has a lower melting temperature than the sheet to form a composite
sheet; (2) thermoforming the composite sheet into a composite
energy-absorbing countermeasure; and (3) applying a second means
for adhering to a headliner layup and heating the headliner layup
to an optimum temperature to form a bond between the headliner
layup and the composite energy-absorbing countermeasure, the
headliner layup including a headliner core and a cover stock.
8. The process of claim 1 wherein optional step (1A) is absent and
the optional use of a means for adhering in step (3) is
present.
9. The process of claim 1, wherein optional step (1A) is present
and the optional use of a means for adhering in step (3) is
absent.
10. The process of claim 1, wherein the means for adhering in step
(1A) comprises the means for adhering in step (3).
11. The process of claim 1, wherein the means for adhering in step
(3) comprises the means for adhering in step (1A).
12. The process of claim 2, wherein the trimming step is performed
by a step selected from the group consisting of a waterjet process,
a laser process and combinations thereof.
13. The process of claim 1, further comprising the step of applying
a fluid pressure within an energy-absorbing unit after the
headliner layup is bonded to the energy-absorbing countermeasure so
that a bulge is created in the headliner layup so that its "A"
surface extends convexedly outwardly in conformance with contours
defined by an upper headliner form tool.
14. The process of claim 1 further comprising the step of
in-molding one or more components selected from the group
consisting of wiring harnesses, clips, brackets, and the like.
15. A process for attaching an energy-absorbing countermeasure to a
headliner for use in a vehicle, comprising the steps of: preparing
an energy-absorbing countermeasure; preparing a headliner layup
including a headliner core and a cover stock; applying to either or
both of the countermeasure and the layup a means for adhering the
countermeasure and the headliner layup; and heating the headliner
layup to an optimum temperature to form a bond between the
headliner layup and the energy-absorbing countermeasure.
16. A process for forming a headliner with an attached thermoformed
energy-absorbing countermeasure for use in a vehicle, comprising
the steps of: positioning an energy absorbing countermeasure
adjacent an upper surface of a headliner forming core, and heating
and forming the headliner forming core and countermeasure together
to form a bond therebetween and to shape the headliner forming core
into a shaped headliner configuration which will allow it to be
installed in a vehicle.
17. The process of claim 16, wherein the step of heating and
forming comprises: providing a headliner forming tool that is
shaped and has a topography that defines an assembly of the
energy-absorbing countermeasure and the formed headliner core.
18. The process of claim 17, wherein the heating step comprises:
heating the headliner forming core and countermeasure together to a
temperature of about 375.degree. F.
19. The process of claim 16, further comprising the steps of:
positioning one or more additional components selected from the
group consisting of wiring harnesses, clips, brackets, and the like
adjacent the upper surface of a headliner forming core, and heating
and thermoforming the headliner forming core, countermeasure and
one or more additional components together to form a bond between
them and the core, and to shape the headliner forming core into a
shaped headliner configuration which will allow it to be installed
in a vehicle.
20. A process for forming a headliner with one or more attached
components for use in a vehicle, comprising the steps of:
positioning one or more components selected from the group
consisting of wiring harnesses, clips, brackets, thermoformed
energy-absorbing countermeasures and the like adjacent the upper
surface of a headliner forming core, and heating and thermoforming
the headliner forming core and said one or more components together
to form a bond between said one or more components and the core,
and to shape the headliner forming core into a shaped headliner
configuration which will allow it to be installed in a vehicle.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of prior U.S. application
Ser. No. 11/044,573 filed Jan. 27, 2005.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to protecting an occupant in a vehicle
when the vehicle is on the giving or receiving end of an impact.
More particularly, it relates to a method for in-molding an energy
absorber to a headliner and the assembly created thereby.
[0004] 2. Background Art
[0005] The National Highway Traffic Safety Administration's (NHTSA)
Federal Motor Vehicle Safety Standard 201 (FMVSS201), entitled
"Occupant Protection in Interior Impact," spells out the criteria
for upper interior impact protection of an occupant in a motor
vehicle. NHTSA estimates that even with airbags, (1) the vehicle
occupant's impact with the pillars, roof-side rails, windshield
header and rear header results in many passenger car occupant
fatalities; and (2) head impacts cause many moderate to critical
(potentially fatal) passenger car occupant injuries. Manufacturers
decide how to meet the requirements of FMVSS201. A popular method
of compliance is the installation of energy-absorbing
countermeasures such as padding, which manufacturers hope will
reduce the number and severity of injuries.
[0006] Today's vehicles are equipped with a burgeoning array of
devices. Some are installed for safety, such as airbags and energy
absorbers. In most cases, the cost of material, manufacturing, and
installation of all related components becomes a significant factor
in overall manufacturing economics.
[0007] In some cases, one or more energy absorbers is or are glued
to one side of a headliner. Gluing steps, however, take time, and
entail material costs. Further, the area of contact between the
headliner and energy absorber may be discontinuous if the glue is
not applied uniformly to the entire underside of the energy
absorber that is to be bonded with the headliner.
[0008] A search that preceded the filing of this application
revealed the following U.S. references: U.S. Pat. Nos. 6,204,209
B1; 6,368,702 B1; 6,231,072 B1; 6,582,639 B2; 6,652,021 B1;
6,779,835 B2; 6,832,810 B2; 2002/0013686 A1; 2002/0190506 A1 and
2004/0178662 A1.
SUMMARY OF THE INVENTION
[0009] The invention has two overall aspects: a process for
attaching an energy-absorbing countermeasure to a headliner for use
in a vehicle; and the resulting assembly of an energy-absorbing
countermeasure and a headliner.
[0010] Preferably, the process comprises the steps of:
[0011] (1) preparing a sheet (a strip of plastic, for example);
[0012] (1A) optionally, laminating to the sheet a means for
adhering (e.g., a film, a spray coat, a co-extruded film or a
roll-coated film) that has a lower melting temperature than the
sheet to form a composite sheet;
[0013] (2) heating the composite sheet and thermoforming it into a
composite energy-absorbing countermeasure; and
[0014] (3) heating a headliner layup to an optimum temperature and
generating a melt bond between the headliner layup and the
composite energy-absorbing countermeasure. Optionally, the
headliner layup includes a bonding promoter (such as another or the
same means for adhering used in step (1A)), a headliner core, and a
cover stock. No glue is needed.
[0015] It will be appreciated that several alternatives are
available for the bonding materials or films, including: adhesive
web, a melt bond adhesive, various polymers, heat activated
catalysts, and the like.
[0016] The invention also includes the intermediate and final
assembly of an energy-absorbing countermeasure--available in
various forms e.g. a thermoformed or injection-mold plastic or
foam, including expanded foam, EPP, PP and PU--and a headliner.
Preferably, the final assembly comprises an energy-absorbing
countermeasure formed from the sheet, including means (such as a
base or tether) for coordinating energy absorbing units. One or
more energy absorbing units (such as cup-shaped recesses) are
associated with the means for coordinating. The coordinating means
position the units in relation to each other before, during and
after relative motion between an incident object and the
energy-absorbing countermeasure.
[0017] At least some of the units have an intermediate wall before
impact. The units cooperate to afford mutual support in
decelerating an object that imparts the impacting force so that
those forces are at least partially absorbed. Optionally, a first
means for adhering adheres to at least a part of an underside of
the energy-absorbing countermeasure. As used herein, the term
"means for adhering" means any substance, inorganic or organic,
natural or synthetic, that is capable of bonding the
energy-absorbing countermeasure to the headliner layup together by
surface attachment. Synthetic organic compounds include, for
example, elastomer-solvent cements, polysulfide sealants,
thermoplastic resins (for hot-melts) such as polyethylene,
isobutylene, polyamides, polyvinyl acetates, and thermosetting
resins, including epoxy, phenoformaldehyde, polyvinyl butyral, and
cyanocrylates. Also exemplary of a means for adhering is the notion
of hot-melt adhesion wherein a solid, thermoplastic material
quickly melts upon heating, and then sets to a firm bond on
cooling. This offers the possibility of almost instantaneous
bonding. Typical ingredients of hot-melts are polyethylene,
polyvinyl acetate, polyamides, and hydrocarbon resins. If desired,
rubber-based adhesives may also be used. These include a solution
of natural or synthetic rubber in a suitable organic solvent, a
rubber latex, and silicone rubber cement.
[0018] Optionally, a second means for adhering which may or may not
be equivalent to the first means for adhering, extends over at
least part of a top surface of a headliner core. The headliner core
is positioned so that it is initially separated from the underside
of the energy-absorbing structure by the first and the second means
for adhering until the means for adhering are juxtaposed. The
second means for adhering becomes bonded to the first means for
adhering when the means for adhering are heated and urged together.
A headliner cover stock is affixed to at least a part of a second
surface of the headliner core.
[0019] Alternative ways of practicing the present invention include
applying an adhering means to the energy-absorbing countermeasure,
or to the headliner layup, or to both.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a side-by-side process flow diagram comparing
current and proposed processes for attaching an energy-absorbing
countermeasure to a headliner;
[0021] FIG. 2 is a cross sectional view of a portion of an
intermediate assembly of an energy-absorbing countermeasure and a
headliner before closure to form a final assembly;
[0022] FIG. 3 is a cross-sectional view of a pressurized in-molding
step;
[0023] FIG. 4 is a cross-sectional view of an energy-absorbing
countermeasure in an intermediate manufacturing process stage;
and
[0024] FIG. 5 depicts the results of applying a source of fluid
pressure from within an energy-absorbing unit so that the headliner
layup conforms to an upper headliner forming tool.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
The Process
[0025] Reference is first made to FIG. 1. Steps 1-5 of the left
hand column are the main steps involved in conventional ways to
attach an energy-absorbing countermeasure to a headliner. In brief,
those steps include:
[0026] 1. A polymer, usually in pellet form, is converted to an
extruded sheet.
[0027] 2. The sheet is then heated and thermoformed into a
countermeasure. If desired, the countermeasure can be shaped in
three dimensions to conform to the environmental constraints into
which the energy-absorbing countermeasure is to be installed. The
thermoformed countermeasure is then trimmed, labeled, stacked,
packaged and shipped to the headliner assembly plant.
[0028] 3. A headliner is manufactured by any suitable process.
Illustrative are those disclosed in U.S. Pat. Nos. 6,832,810;
6,582,639; 6,204,209; and 6,368,702. The disclosures of these U.S.
patents are incorporated herein by reference. Suppliers of the
headliner core include Azdel. The headliner is usually manufactured
by combining a layup of the headliner core, a thin polymer means
for adhering, and selected cover stock. The layup is heated, formed
and cooled until it is dimensionally stable. Conventionally, the
typical headliner includes a face fabric, an adhesive, a
reinforcement fiber, and a composite of adhesives, foam, fiber, and
scrim. Details of the headliner product are considered to be within
the knowledge of those of ordinary skill in the art, and so are not
replicated here.
[0029] 4. The untrimmed headliner is then trimmed using a selection
from several known processes: water jet, laser, or other cutting
technology.
[0030] 5. Conventionally, to secure the countermeasure to the
headliner, a hot melt adhesive is supplied to one or both of the
headliner or the countermeasure. The two parts are then brought
into contact under pressure while the adhesive is active and is
cured.
[0031] The right hand column of FIG. 1 describes the process steps
that are involved in practicing the teachings of the present
invention. Steps that correspond to those of the prior art have a
common reference numeral. The main differences are that step (1A)
is needed between steps 1 and 2; and a separate step 5 (gluing) is
avoided because attachment occurs during the headliner forming step
(in-molding). For ease of reference, the process steps 1-4 in FIG.
1 have the same numerals as the process steps set forth in claims
1-2.
[0032] The inventive process for attaching an energy-absorbing
countermeasure to a headliner involves the following steps:
[0033] 1. A sheet is prepared from which the energy-absorbing
countermeasure is made.
[0034] 1A. Optionally, a means for adhering (if a film, preferably
about 0.065'' to 0.0015'' thick) that has a lower melt temperature
than the sheet is then affixed to the sheet (FIG. 2). The means for
adhering include lamination, co-extrusion, roll coating, and
spraying, for example. In this step, a composite sheet is formed,
and may be coiled.
[0035] 2. The composite sheet is then heated and thermoformed into
a composite energy-absorbing countermeasure. In this step, the
composite sheet is heated to an approximate temperature of
320.degree. F.
[0036] 3. The composite energy-absorbing countermeasure is then
loaded into a headliner forming tool. A headliner layup--optionally
including a bonding promoter (typically, a thin polymer film), a
headliner core, and a cover stock--is heated to an optimum
temperature (about 375.degree. F.). It is then moved into contact
with the composite energy-absorbing countermeasure by closing the
form tool. A bond is formed between the heated "B" surface of the
cover stock, the heated headliner core and the countermeasure when
the assembly is subjected to pressure. As a result of this step, an
untrimmed headliner assembly is prepared.
[0037] Conventionally, the "A" surface is the surface that is
closest to a vehicle driver when sitting in the car. Thus, in step
3, the headliner layup is placed into a clamping frame so that its
"A" surface is uppermost. A clamping force is then applied.
Preferably, the force is applied parallel to two opposing longer
edges for uniformity of pressure distribution. However, clamping
force could also be applied to two opposing shorter edges, or
variations thereof. The "A" surface is placed face up because most
headliners are concave. During the heating step, the layup tends to
sag under heat and gravity, thereby creating a naturally concave
shape.
[0038] Unlike conventional approaches, no hot melt adhesive is
needed in order to secure the energy-absorbing countermeasure to
the headliner. As a result of the disclosed process steps, the
energy-absorbing countermeasure is in-molded and is permanently
attached to the headliner. Most, if not all, of the means for
coordinating are in contact with the means for adhering. As a
consequence, bonding forces between the countermeasure and the
headliner are spread relatively uniformly across their entire
interface, rather than being concentrated only in those regions in
which (under prior art approaches) a glue has been applied.
[0039] The invention process thus avoids the conventional step (5)
of applying a hot melt adhesive to the backside of the headliner
core material. For efficiency, the time required in holding the two
surfaces to be joined to allow curing in a subsequent assembly step
is avoided. Further, the area of contact between the
energy-absorbing structure and the headliner is extended.
[0040] In the heating cycle (step 3), the headliner layup is heated
for about 45 to 75 seconds until the "B" surface (lower surface) of
the headliner core reaches a temperature of approximately
375.degree. F. The lower surface is exposed to more heat than the
upper surface since the class A cloth surface is more sensitive to
heat. The energy-absorbing countermeasure is supported and contacts
the lower form tool primarily in the means for coordinating outside
the energy-absorbing units. The layup is compressed and a bond is
formed between the headliner layup and the energy-absorbing
structure while the headliner is being made.
[0041] It will be appreciated that depending upon the shape of the
male and female tool, the headliner to be shaped can assume various
topographies: it could, for example, be crowned, if desired.
[0042] Another attribute of the invention is that it satisfies
"pull" tests. One test of bonding between the materials revealed
that a force of about 220 Newtons was required to separate first
and second film layers. In contrast, one customer required that the
layers withstand minimum separating forces up to about 50
Newtons.
[0043] It should also be realized that without regard to its method
of application, included within the scope of the invention lies
polymer films, and those made of polyvinyl chloride,
thermoplastics, polyurethane, polyesters, polypropylene,
polyethylene, polyolefins, polyvinyl acetal (EAA), ethylene/acrylic
acid, and blends thereof.
[0044] In practice, a coating of a material such as Teflon.RTM. can
be beneficially applied to either the headliner forming tool
surface or the countermeasure tool forming surface or both to avoid
unwanted adhesion.
The Assembly
[0045] FIG. 2 depicts the main components of the assembly of an
energy-absorbing countermeasure and the headliner. Preferably, the
energy-absorbing countermeasure 12 includes means (e.g., a base)
for coordinating energy-absorbing units 24 (e.g., a cup-shaped
recess). It will be appreciated that the form of the
energy-absorbing countermeasure can be "customized" or "tuned" to
produce predefined energy absorption characteristics within spatial
constraints that may be imposed by a particular application.
[0046] As used herein, the energy-absorbing countermeasure 12
includes an assembly of recesses that are provided with means for
coordinating the energy-absorbing units 22 therewithin. The means
for coordinating 22 is terminated by a continuous periphery. Within
the periphery, the means for a coordinating 22 may be planar,
curved, or curvilinear. The coordinating means 22 may have a flat
or curved topography with a variable number (n) of apertures, where
n is an integer greater than or equal to zero. Thus, the means for
coordinating 22 may alternatively include a base, web, a tether, a
hinge, a planar or curved surface, and wings or combinations
thereof that serve to position and support the energy-absorbing
units 24 in relation to each other. One or more of the
energy-absorbing units 24 are associated with the means for
coordinating 22. Those means 22 coordinate the positioning of the
energy-absorbing units 24 in relation to each other before, during,
and after relative motion between an incident object and the
energy-absorbing countermeasure.
[0047] At least some of the energy-absorbing units 24 have an
interior wall surface 26. They cooperate to afford mutual support
through the means for coordinating 22. The interior wall surface 26
is effectively a crushable member of an energy-absorbing unit 24.
Either its upper or lower extremities can be presented to the
headliner or the impacting force, but it is preferable that the
lower extremity be presented to the headliner, as depicted in FIG.
2.
[0048] If desired, the interior wall surface 26 of an
energy-absorbing unit 24 may be provided with a number (m) of
breaches that are defined therewithin before impact, where m is an
integer greater than or equal to zero. The breaches can be defined
by slits (no material removed) or slots (material removed to form
an opening), or both. Thus, within a given energy-absorbing
countermeasure, the means for coordinating may or may not be flat,
may or may not have a number (n) of apertures; one or more of the
energy-absorbing units may be provided with a number (m) of
breaches (e.g., slits or slots, or slits and slots, or neither
slits nor slots); and the means for coordinating may be provided
with a flat or curved topography.
[0049] If desired, at least some of the energy-absorbing units 24
may have a volcano or crater-shaped floor which may be domed,
concave, or convex in order to impart particular energy-absorbing
characteristics to an energy-absorbing unit.
[0050] U.S. patent application Ser. No. 11/014,418, filed on Dec.
16, 2004 (which is incorporated herein by reference) discloses that
in a given application, a number of energy-absorbing
countermeasures may be affixed to a substrate and that the
substrate helps to position and configure the energy-absorbing
countermeasures. One non-limiting example was disclosed: a
vehicular headliner that extends across a "B" pillar. It will be
appreciated however that the scope of the present invention is not
limited to a specific position of the headliner in the vehicle, nor
to the headliner itself as a substrate.
[0051] It is contemplated, for example, that the disclosed
structure can be used in both head and side impact occupant
protection applications. In either case, one or more
energy-absorbing countermeasures may be mounted between the
interior trim (headliner) and the body structure of an automobile
(often where space is limited). Designs of specific forms of
energy-absorbing countermeasure vary greatly when customizing them
to fit and perform within a geometrical environment and constraints
into which they are packaged. In decelerating an object that
imparts the impacting force, impacting forces are at least
partially absorbed by the energy-absorbing units and the
headliner.
[0052] If desired, a first means for adhering 14 adheres to at
least a part of the interior wall surface 26 and an underside 28 of
the means for coordinating 22. Before closure of the forming tool,
the headliner core 18 is positioned so that it is spaced apart from
the underside 28 of the coordinating means 22. When used, a second
means for adhering 16 extends over at least a portion of the top
surface 30 of the headliner core 18 so that the second means for
adhering 16 is separated from the first means for adhering 14. It
will be appreciated that the use of an adhering means can be made
either on the countermeasure, or the headliner layup, or on both
surfaces.
[0053] A headliner cover stock 20 is affixed to at least a part of
a second surface 32 of the headliner core 18. After the tool is
closed, an assembly of the energy-absorbing countermeasure and a
headliner is formed without an adhesive.
[0054] The energy-absorbing countermeasures are preferably made
from polymers. Balancing cost, performance and formability, a
selection of polypropylene (PP) and acrylonitirile butadenine
styrene (ABS) material grade can be used. Specifically, these
include Basell Polyolefins Pro-Fax SV152, polypropylene copolymer
(SV152), BP Petro Chemicals polypropylene copolymer 3045, and
General Electric Cycolac EX75 (EX75).
[0055] A particular energy-absorbing countermeasure may include a
hinge section with leaves. Each leaf may extend from one of the
energy-absorbing countermeasures so that they may be configured
within the spatial constraints that are imposed by the environment
at use.
[0056] If desired, an energy-absorbing countermeasure may be
provided with cooperating means that may take the form of an
adhesive, a clip, a vibration weld, a sonic weld, a heat stake, a
"tongue-in-groove" arrangement, and the like--all serving the
purpose of enabling the energy-absorbing countermeasure and
headliner assembly to be attached to a vehicle structure or to
enable an object to be attached to the assembly. Further, channels
may be provided between energy-absorbing countermeasures to
accommodate wiring, for example. Additionally, the channels may
promote stiffness in one direction versus flexibility in another,
if desired. Further, if desired, stiffening ribs can be provided
between one or more energy-absorbing countermeasures to enhance the
stiffness characteristic at selected locations.
[0057] This affords latitude to a designer who may wish to provide
stiffness in one direction for impact resistance, yet flexibility
in another direction to enable a given energy-absorbing module to
bend or conform to the spatial constraints imposed by the
environment in which the energy-absorbing countermeasure is to be
installed.
[0058] For example, in certain environments a protrusion such as an
HVAC duct, a coat hook, a sun visor, a wiring harness, or the head
of a bolt may invade the space that would be occupied by a vehicle
occupant. Ideally, it would be desirable to provide an
energy-absorbing countermeasure having enhanced stiffness
characteristics around such a protrusion. One way to provide such
an absorber is to configure an energy-absorbing unit with an inner
wall that may be configured or "tuned" independently of the
energy-absorbing characteristics of the outer wall surface. In this
way, a floor at the foot of an inner wall (in a volcano structure,
for example) may effectively bottom out during energy-absorption so
that the amount of resistance to greater deflection is more than
the resistance offered before bottoming out.
[0059] Another advantage of the disclosed invention is that various
energy-absorbing characteristics can be imparted to specific
locations within a vehicle while avoiding a "bleed through" of the
energy-absorbing countermeasure to the class A surface, the
appearance of which is important to the vehicle buyer or owner.
[0060] In certain instances, there may be large recesses on a
contoured headliner surface that may be wholly or partially covered
by an energy-absorbing countermeasure. In such situations, the
addition of air pressure within the energy-absorbing units may be
usefully deployed to urge the headliner material to the "A" surface
to prevent bleedthrough. FIGS. 4 and 5 depict the situation.
[0061] Upon tool closing, a seal is made between the means for
coordinating and the backside of the headliner core. A separate
nozzle with a flexible gasket provides a seal at the pressure
inlet.
[0062] Air pressure is applied while the form tool is closed. The
resulting pressure generated in the recess/rib cavity forces the
layup to the headliner form tool A surface.
[0063] In FIG. 4, there is a void to be filled between the upper
headliner forming tool and the headliner layup. Pressure is needed
inside the energy-absorbing unit to urge the layup to conform to
the "A" surface and to the forming tool.
[0064] FIG. 5 shows the results. In FIG. 5, the headliner layup and
its cover conform to the headliner forming tool "A"-surface. This
is achieved by the application of fluid (e.g., air) pressure from a
source that is directed through one or more ribs that communicate
to at least some of the energy-absorbing units.
[0065] It will be appreciated that the invention is not limited to
the preferred embodiment (discussed earlier) of energy-absorbing
countermeasure. Rather, this term is meant to embrace other forms
of energy-absorbing countermeasure, such as injection molded rib
cartridges, and foam countermeasures.
[0066] Thus, the disclosed process involves making an
energy-absorbing countermeasure and making a headliner layup while
integrally molding in the previously made countermeasure.
[0067] While embodiments of the invention have been illustrated and
described, it is not intended that these embodiments illustrate and
describe all possible forms of the invention. Rather, the words
used in the specification are words of description rather than
limitation, and it is understood that various changes may be made
without departing from the spirit and scope of the invention.
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