U.S. patent application number 10/854074 was filed with the patent office on 2004-11-04 for method of preparing a molded article having a rigid support and a flexible hollow member.
Invention is credited to Cooper, Christopher, DiBattista, Gerald A..
Application Number | 20040217521 10/854074 |
Document ID | / |
Family ID | 21981458 |
Filed Date | 2004-11-04 |
United States Patent
Application |
20040217521 |
Kind Code |
A1 |
DiBattista, Gerald A. ; et
al. |
November 4, 2004 |
Method of preparing a molded article having a rigid support and a
flexible hollow member
Abstract
A method of preparing a molded article comprising (a) a rigid
support, e.g., a rigid seat support (10), having a plurality of
perforations, and (b) a molded flexible hollow thermoplastic member
(20), e.g., a flexible thermoplastic seat cushion, fixedly attached
thereto is described. During the blow molding step a portion of the
thermoplastic parison precursor of the flexible hollow member (b)
extends through at least some of the perforations of the rigid
support (a), embedding the edges of the perforations therein. The
flexible material extending through the perforations forms an
attachment means, e.g., an attachment head, that serves to fixedly
attach the flexible hollow member (b) to the rigid support (a).
Inventors: |
DiBattista, Gerald A.;
(McDonald, PA) ; Cooper, Christopher; (Moon
Township, PA) |
Correspondence
Address: |
LANXESS CORPORATION
PATENT DEPARTMENT/ BLDG 14
100 BAYER ROAD
PITTSBURGH
PA
15205-9741
US
|
Family ID: |
21981458 |
Appl. No.: |
10/854074 |
Filed: |
May 26, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10854074 |
May 26, 2004 |
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10053028 |
Jan 17, 2002 |
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6783184 |
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Current U.S.
Class: |
264/529 ;
264/534 |
Current CPC
Class: |
B29K 2105/0005 20130101;
B29K 2705/02 20130101; B29C 2049/2017 20130101; B29L 2031/771
20130101; B29C 2049/206 20130101; B29K 2995/0082 20130101; B29C
49/04 20130101; B29C 49/0047 20130101; B29L 2022/027 20130101; B29C
49/20 20130101; Y10S 297/02 20130101; B29K 2105/04 20130101; B29K
2705/12 20130101; Y10T 428/24322 20150115; B29C 67/246 20130101;
B29K 2105/06 20130101 |
Class at
Publication: |
264/529 ;
264/534 |
International
Class: |
B29C 049/20 |
Claims
1. (Cancelled).
2. The method of claim 35 wherein said rigid support is fabricated
from a material selected from metal, thermoset plastic material,
thermoplastic material and combinations thereof.
3. The method of claim 2 wherein said rigid support is fabricated
from thermoplastic material optionally reinforced with a material
selected from glass fibers, carbon fibers, metal fibers, polyamide
fibers and mixtures thereof.
4. The method of claim 35 wherein the thermoplastic material of
said flexible member is selected from at least one of thermoplastic
vulcanizates, thermoplastic polyolefins, thermoplastic
polyurethanes, thermoplastic polyureas, thermoplastic polyamides,
thermoplastic polyesters and thermoplastic polycarbonates.
5. The method of claim 35 wherein said flexible hollow
thermoplastic member has an outer surface, and said mold has
interior surfaces, said method further comprising, placing a fabric
insert in contact with at least a portion of the interior surfaces
of said mold, and said thermoplastic parison contacting and fusing
with said fabric insert during said blow molding step, said
flexible hollow thermoplastic member thereby having a fabric
covering on at least a portion of said outer surface of said
flexible hollow thermoplastic member.
6. The method of claim 35 wherein said flexible hollow
thermoplastic member has an outer surface, and said mold has
interior surfaces, at least a portion of the interior surfaces of
said mold having at least one surface feature selected from the
group consisting of raised portions and recesses, said method
further comprising, contacting said thermoplastic parison with said
interior surfaces of said mold, at least a portion of the outer
surface of said flexible hollow thermoplastic member thereby having
molded-in texture.
7. The method of claim 35 wherein said flexible hollow
thermoplastic member has an outer surface, and said mold has
interior surfaces, said method further comprising, placing a film
insert in contact with at least a portion of the interior surfaces
of said mold, and said thermoplastic parison contacting and fusing
with said film insert during said blow molding step, said flexible
hollow thermoplastic member thereby having an integral film on at
least a portion of said outer surface of said flexible hollow
thermoplastic member.
8. The method of claim 35 wherein said flexible member is further
fixedly attached to said rigid support by attachment means selected
from fasteners, adhesives and combinations thereof.
9. The method of claim 35 wherein the hollow interior of said
flexible member is filled with a material selected from,
pressurized gas, liquid, gel, polymeric foam and combinations
thereof.
10. The method of claim 35 wherein said flexible member comprises
means for reversibly increasing pressure within the hollow interior
of said flexible member.
11. The method of claim 10 wherein said means for reversibly
increasing pressure within the hollow interior of said flexible
member comprises at least one pressure regulating valve that
provides fluid communication with the hollow interior of said
flexible member, and one of (i) a heated liquid and (ii) a cooled
liquid are reversibly introduced into the hollow interior of said
flexible member through said at least one pressure regulating
valve.
12. The method of claim 35 wherein said article is a seat.
13. The method of claim 12 wherein said rigid support comprises a
rigid seat back support and a rigid seat bottom support, and said
flexible member comprises flexible cushions fixedly attached to
each of said rigid seat back support and rigid seat bottom
support.
14. The method of claim 12 wherein said rigid support is a
continuous unitary unit.
15. The method of claim 35 wherein at least some of said
perforations have deformed edge portions, and said deformed edge
portions are embedded in the plastic material of said thermoplastic
parison extending therethrough during said blow molding step.
16. The method of claim 35 wherein said rigid support is a rigid
hollow support having an exterior surface and a hollow interior,
said flexible member is in abutting relationship with at least a
portion of the exterior surface of said hollow support, at least a
portion of said flexible member extends through at least some of
said perforations into the hollow interior of said rigid hollow
support.
17. The method of claim 35 wherein said rigid support has a
plurality of anchoring extensions extending into said flexible
member, each of said anchoring extensions having walls, an interior
chamber and at least one wall perforation in said walls, each wall
perforation having edges, a portion of the thermoplastic material
of said thermoplastic parison extends through at least some of said
wall perforations into said chamber during said blow molding step,
the edges of said wall perforations being embedded in the plastic
material extending therethrough, thereby fixedly attaching said
flexible member to said rigid support.
18. The method of claim 35 wherein said rigid support has edges,
and said flexible member is further fixedly attached to said rigid
support by means of portions of said thermoplastic parison wrapping
around and embedding at least a portion of the edges of said rigid
support during said blow molding step.
19-34. (Cancelled).
35. A method of preparing a molded article comprising a molded
flexible hollow thermoplastic member fixedly attached to a rigid
support, said method comprising: (a) placing said rigid support in
a mold, said rigid support having a plurality of perforations
having edges, a first surface and a second surface; and (b) blow
molding a thermoplastic parison precursor of said flexible member
against the first surface of said rigid support; wherein a portion
of the thermoplastic material of said thermoplastic parison extends
through at least some of said perforations of said rigid support,
the edges of said perforations being embedded in the plastic
material extending therethrough, thereby attaching fixedly said
flexible member to said rigid support.
36. The method of claim 35 wherein during blow molding step (b), at
least one of (i) increased gaseous pressure is provided on the
interior of said thermoplastic parison, and (ii) reduced gaseous
pressure is provided on the second surface of said rigid support,
thereby forcing portions of said thermoplastic parison through at
least some of said perforations during said blow molding step.
37. The method of claim 7 wherein said mold has an interior, said
film insert has a first surface and a second surface, said first
surface being opposed from said second surface, said first surface
contacting at least a portion of the interior surfaces of said
mold, said second surface of said film insert facing said interior
of said mold and fusing with said parison during said blow molding
step, said film insert having at least one member selected from the
group consisting of indicia, patterns and printing on at least one
of said first surface and said second surface of said film insert.
Description
DESCRIPTION OF THE INVENTION
[0001] The present invention relates to a molded article comprising
a rigid support having a plurality of perforations, and a molded
flexible hollow member of thermoplastic material. Portions of the
flexible hollow member extend through at least some of the
perforations of the rigid support, and the edges of the
perforations are embedded in the flexible material extending there
through. The flexible material extending through the perforations
serves to fixedly attach the flexible member to the rigid support.
The present invention also relates to a process of preparing the
molded article.
[0002] Flexible hollow thermoplastic articles, e.g., cushions, can
be prepared by means of thermoplastic blow molding processes. Blow
molding typically involves a multi-stage process. In the first
stage, a flexible thermoplastic feed material, e.g., in the form of
pellets, is extruded, typically in an extruder, and the resulting
molten extrudate is passed through a die to form a hollow molten
tube, which is referred to as a parison. The parison is drawn
through or into an open mold. The mold is closed around the
parison, pinching off at least one end of the parison. Compressed
gas is then fed into the interior of the parison, which expands to
fill the interior of the closed mold. While maintaining the
internal pressure within the parison, the expanded parison is
allowed to cool and solidify within the mold. The pressure within
the solidified parison is released, the mold is opened, and a
flexible hollow blow molded article is removed. Flexible hollow
thermoplastic articles may also be prepared by other art recognized
processes, which include, for example, twin-sheet thermoforming,
rotational molding, thermoplastic welding (e.g., vibration and/or
radio frequency welding), two-piece over-molding and lost-core
molding.
[0003] The flexible hollow thermoplastic member or bladder,
prepared for example by blow molding, is typically attached to a
support structure. In the case of seat cushions, the flexible
hollow thermoplastic bladder is attached to a seat back support
and/or seat bottom support by means of, for example, a fabric
jacket. The fabric jacket is attached to the support structure,
e.g., by means of rivets and/or loops, and covers and tightly holds
the flexible hollow thermoplastic bladder against the support
structure. The flexible bladder may also be further or
alternatively attached to the support structure by means of, for
example, adhesives. The flexible bladder or cushion may be filled
with air, or another material, such as a polymeric foam, e.g., a
polyurethane foam.
[0004] Such methods of attaching flexible hollow thermoplastic
bladders or cushions to a support structure, as described above,
typically involve a series of manufacturing steps, and the use of
additional materials, e.g., fabric jackets, rivets and adhesives.
In addition, the position of the flexible hollow thermoplastic
bladder or cushion can undesirably shift relative to or pull away
from the support structure.
[0005] A need accordingly exists to develop molded articles, e.g.,
cushioned seats, in which the molded flexible hollow thermoplastic
member, such as a bladder or cushion, is more securely fixed or
attached to the rigid support of the article. A need also exists
with regard to the development of new methods of preparing such
molded articles in which the flexible member is concurrently molded
and fixedly attached to the support structure, thereby reducing the
number of manufacturing steps required.
[0006] U.S. Pat. No. 6,120,100 discloses a head rest assembly that
is fabricated by a blow molding process, and which includes a skin
surrounding a foam cushion, and an insert secured to the skin. The
skin includes a channel dimensioned to receive the peripheral edge
of the insert therein. The insert may be adhered to the skin either
before or during the blow molding process.
[0007] In accordance with the present invention, there is provided
a molded article comprising:
[0008] (a) a rigid support having a surface and a plurality of
perforations having edges; and
[0009] (b) a molded flexible member of thermoplastic material, at
least a portion of said flexible member being in abutting
relationship with at least a portion of the surface of said
support, said flexible member having a hollow interior,
[0010] wherein a portion of said flexible member extends through at
least some of the perforations of said rigid support, the edges of
said perforations being embedded in the portions of the flexible
member extending therethrough, thereby fixedly attaching said
flexible member to said rigid support.
[0011] In further accordance with the present invention, there is
also provided a method of preparing a molded article comprising a
molded flexible hollow thermoplastic member fixedly attached to a
rigid support, said method comprising:
[0012] (a) placing said rigid support in a mold, said rigid support
having a plurality of perforations having edges, a first surface
and a second surface; and
[0013] (b) blow molding a thermoplastic parison precursor of said
flexible member against the first surface of said rigid
support;
[0014] wherein a portion of the thermoplastic material of said
thermoplastic parison extends through at least some of said
perforations of said rigid support, the edges of said perforations
being embedded in the plastic material extending therethrough,
thereby attaching fixedly said flexible member to said rigid
support.
[0015] The features that characterize the present invention are
pointed out with particularity in the claims, which are annexed to
and form a part of this disclosure. These and other features of the
invention, its operating advantages and the specific objects
obtained by its use will be more fully understood from the
following detailed description and accompanying drawings in which
preferred embodiments of the invention are illustrated and
described.
[0016] Unless otherwise indicated, all numbers or expressions, such
as those expressing structural dimensions, quantities of
ingredients, etc. used in the specification and claims are
understood as modified in all instances by the term "about."
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a representative perspective view of a molded seat
according to the present invention which comprises a rigid support
10 and a molded flexible hollow thermoplastic member 20 fixedly
attached thereto;
[0018] FIG. 2 is a representative partial cut-away perspective view
of the molded seat of FIG. 1;
[0019] FIG. 3 is a representative perspective view of the back of
the molded seat of FIG. 1;
[0020] FIG. 4 is a representation of a section of an attachment
means through line A-A of FIG. 3;
[0021] FIG. 5 is a sectional representation of an anchoring
extension extending into the molded flexible hollow thermoplastic
member of a molded seat according to the present invention;
[0022] FIG. 6 is a sectional representation of an attachment means
similar to that of FIG. 4; and
[0023] FIG. 7 is a sectional representation of a wrap-around
attachment means, in which a portion of flexible hollow member (b)
wraps around and embeds at least a portion of the edges of rigid
support (a) therein.
[0024] In FIGS. 1 through 7, like reference numerals designate the
same components and structural features.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Referring now to FIG. 1 of the drawings, there is shown a
molded seat 2 according to the present invention, which includes a
rigid seat support 10 and a molded flexible cushion 20. Rigid seat
support 10 is a unitary unit and includes a rigid seat back support
17 and a rigid seat bottom support 14. Flexible cushion 20 is a
continuous member and includes a back cushion portion 23 and a
bottom cushion portion 26. The outer surface of flexible cushion 20
has raised molded-in features 29. Rigid seat support bottom 14
includes flanges 32 having holes 35 therein, which provide means by
which molded seat 2 can be fixedly attached to a separate support
structure, e.g., the interior of a vehicle or the deck of a tractor
or boat (not shown). Rigid seat support back 17 may also further
include flanges (not shown) for fixedly attaching molded seat 2 to
a separate support structure (not shown).
[0026] The rigid support (a), e.g., rigid seat support 10 of molded
seat 2, of the molded article of the present invention may be
selected from metal, thermoset plastic material, thermoplastic
material and combinations thereof. Metals from which rigid support
(a) may be selected include, but are not limited to, aluminum and
steel. As used herein and in the claims the term "thermoset plastic
material" means plastic materials having a three dimensional
crosslinked network resulting from the formation of covalent bonds
between chemically reactive groups, e.g., active hydrogen groups
and free isocyanate groups. Thermoset plastic materials from which
rigid support (a) may be fabricated include those known to the
skilled artisan, e.g., crosslinked polyurethanes, crosslinked
polyepoxides and crosslinked polyesters. Of the thermoset plastic
materials, crosslinked polyurethanes are preferred. Rigid support
10 may be fabricated from crosslinked polyurethanes by the
art-recognized process of reaction injection molding. Reaction
injection molding typically involves, as is known to the skilled
artisan, injecting separately, and preferably simultaneously, into
a mold: (i) an active hydrogen functional component (e.g., a polyol
and/or polyamine); and (ii) an isocyanate functional component
(e.g., a diisocyanate such as toluene diisocyanate, and/or dimers
and trimers of a diisocyanate such as toluene diisocyanate). The
filled mold may optionally be heated to ensure and/or hasten
complete reaction of the injected components. Upon complete
reaction of the injected components, the mold is opened and the
molded article, e.g., rigid support (a), is removed.
[0027] As used herein and in the claims, the term "thermoplastic
material" means a plastic material that has a softening or melting
point, and is substantially free of a three dimensional crosslinked
network resulting from the formation of covalent bonds between
chemically reactive groups, e.g., active hydrogen groups and free
isocyanate groups. Examples of thermoplastic materials from which
rigid support (a), e.g., rigid seat support 10 of molded seat 2,
may be fabricated include, but are not limited to, thermoplastic
polyurea, thermoplastic polyimide, thermoplastic polyamide,
thermoplastic polyamideimide, thermoplastic polyester,
thermoplastic polycarbonate, thermoplastic polysulfone,
thermoplastic polyketone, thermoplastic polyethylene, thermoplastic
polypropylene, thermoplastic polybutylene terephthalate,
thermoplastic polyvinylchloride, thermoplastic
acrylonitrile-butadiene-styrene, thermoplastic polyurethane and
mixtures or thermoplastic compositions containing one or more
thereof. Of the thermoplastic materials from which rigid support
(a) may be fabricated, thermoplastic polyamides are preferred.
[0028] Rigid support (a) may be fabricated from thermoplastic
materials by the art-recognized process of injection molding, in
which a molten stream of thermoplastic material, e.g., molten
thermoplastic polyamide, is injected into a mold, e.g., an
optionally heated mold. Upon cooling the filled mold, the molded
article, e.g., rigid support (a), is removed. A preferred
thermoplastic material from which rigid support (a) may be
fabricated is thermoplastic polyamide, e.g., DURETHAN thermoplastic
polyamide, commercially available from Bayer Corporation. Other
art-recognized processes by which rigid support (a) may be
fabricated from thermoplastic materials include, but are not
limited to, blow molding and thermoforming.
[0029] The thermoset plastic materials and/or thermoplastic
materials from which rigid support (a) may be fabricated, may
optionally be reinforced with a material selected from glass
fibers, carbon fibers, boron fibers, metal fibers, polyamide fibers
(e.g., KEVLAR polyamide fibers) and mixtures thereof. The
reinforcing fibers, and the glass fibers in particular, may have
sizings on their surfaces to improve miscibility and/or adhesion to
the plastics into which they are incorporated, as is known to the
skilled artisan. Glass fibers are a preferred reinforcing material
in the present invention. If used, the reinforcement material,
e.g., glass fibers, is typically present in the thermoset plastic
materials and/or thermoplastic materials of elongated rigid support
10 in a reinforcing amount, e.g., in an amount of from 5 percent by
weight to 60 percent by weight, based on the total weight of rigid
support (a).
[0030] As used herein and in the claims, the term "rigid" of rigid
support (a) is used relative to the term "flexible" of the molded
flexible thermoplastic member (b). That is, the rigid support (a)
is more rigid than is the flexible hollow member (b), and
correspondingly the flexible hollow member (b) is more flexible
than the rigid support (a). More specifically, the rigid support
(a), when fabricated from a thermoplastic or a thermoset material,
typically has a flexural modulus of at least 1000 MPa, e.g., from
1000 to 15,000 MPa. The flexible hollow member (b) typically has a
flexural modulus of less than 1000 MPa, e.g., less than 100 MPa or
less than 70 MPa.
[0031] The thermoplastic material of the molded flexible hollow
member (b), e.g., flexible thermoplastic cushion 20 of molded seat
2, is selected from at least one of thermoplastic vulcanizates,
thermoplastic polyolefins, thermoplastic polyurethanes,
thermoplastic polyureas, thermoplastic polyamides, thermoplastic
polyesters and thermoplastic polycarbonates. Thermoplastic
vulcanizates are vulcanized alloys of rubber and thermoplastic
materials, having rubber and thermoplastic phases. The rubber phase
of thermoplastic vulcanizates that may be used in the present
invention include, but are not limited to, ethylene propylene diene
rubber, natural rubber and butyl rubber. Examples of thermoplastics
that may form the thermoplastic phase of the thermoplastic
vulcanizates include, for example, polypropylene and polyethylene.
Commercially available thermoplastic vulcanizates that may be used
in the present invention include, for example, KRATON polymers,
commercially available from GLS Corporation, and SANTOPRENE
polymers, commercially available from Advanced Elastomers
Systems.
[0032] Thermoplastic polyolefins from which the flexible hollow
member (b) may be fabricated include, for example, polyethylene,
polypropylene, copolymers of ethylene and propylene, and
polybutylene. Preferred thermoplastic polyolefins include, but are
not limited to, linear low-density polyethylene (LLDPE) and
metallocene linear low-density polyethylene (mLLDPE). In a
preferred embodiment of the present invention, flexible hollow
thermoplastic member (b) is fabricated from thermoplastic
polyurethane, e.g., TEXIN thermoplastic polyurethane or DESMOPAN
thermoplastic polyurethane which are commercially available from
Bayer Corporation.
[0033] The plastic materials of rigid support (a) and flexible
thermoplastic hollow member (b) may each independently further
contain one or more functional additives. Additives that may be
present in the plastic material of the rigid support (a) and/or the
flexible thermoplastic hollow member (b) of the molded article
include, but are not limited to, antioxidants, colorants, e.g.,
pigments and/or dyes, mold release agents, fillers, e.g., calcium
carbonate, ultraviolet light absorbers, fire retardants and
mixtures thereof. Additives may be present in the plastic material
of the rigid support and/or the flexible thermoplastic hollow
member in functionally sufficient amounts, e.g., in amounts
independently from 0.1 percent by weight to 10 percent by weight,
based on the total weight of the plastic material of the rigid
support or the flexible thermoplastic hollow member.
[0034] The flexible thermoplastic hollow member (b), e.g., flexible
cushion 20, of the molded article of the present invention, may be
formed by methods that are known to those of ordinary skill in the
art. Such art recognized methods by which the flexible
thermoplastic hollow member (b) may be prepared include, but are
not limited to, blow molding, twin-sheet thermoforming, rotational
molding, thermoplastic welding (e.g., vibration and/or radio
frequency welding), two-piece over-molding and lost-core molding.
In a preferred embodiment of the present invention, the flexible
hollow thermoplastic member (b) is prepared by blow molding. The
blow molding process is well known to the skilled artisan, and has
been described previously herein.
[0035] In FIG. 2 a sectional perspective view of molded seat 2 of
FIG. 1 is depicted. The sectional perspective view reveals the
hollow interior 41 of flexible thermoplastic cushion 20. Molded-in
support columns (or ribs) 38, which are continuous with molded-in
features 29, are also visible in FIG. 2. Molded-in support columns
38 are composed of the same flexible thermoplastic material as that
of, and are continuous with flexible hollow cushion 20. Typically,
molded-in support columns 38 are formed concurrently with the
formation of flexible hollow member 20. For example, when formed by
blow molding, the interior walls of the mold may have portions
extending therefrom that serve to form molded-in support columns
38. Those portions of the mold interior that are opposite the mold
extensions, may have depressions therein that serve to form
molded-in features 29 during the blow molding process. Molded-in
support columns 38 provide dimensional stability to flexible hollow
cushion 20. Molded-in support columns 38 are also visible through
openings 47 in rigid seat support 10. See FIG. 3.
[0036] The hollow interior 41 of flexible hollow cushion 20 may be
filled with a material selected from pressurized gases, liquids,
gels, polymeric foams and combinations thereof. Pressurized gasses
that may be used to fill hollow interior 41 include, for example,
air and nitrogen, preferably air. Liquids that may be used to fill
hollow interior 41 include, for example, water, a mixture of water
and propylene glycol, and a heat transfer oil. Liquids that may be
used to fill hollow interior 41 also include viscoelastic liquids,
such as viscoelastic liquid polymers, e.g., viscoelastic
polyurethanes, that are known to the skilled artisan. The term
"gel" as used herein and in the claims, with regard to filling the
hollow interior of the flexible member of the molded article of the
present invention, refers to art-recognized gels, which are
typically in the form of viscous jellylike materials, that are used
to provide cushioning, shock absorption and/or vibrational
dampening properties. An example of a class of such gels that may
be used in the present invention are glycerin gels. Examples of
polymeric foams that may be used to fill hollow interior 41 are
preferably flexible polymeric foams, and include those known to the
skilled artisan, e.g., flexible polyurethane foams.
[0037] Filling materials, such as polymer foams, liquid and liquid
gels may be introduced into the flexible hollow-member (b) during
or after the molding process, e.g., blow molding. Filling
materials, such as polymeric foams, may be introduced into the
hollow interior of flexible hollow member (b) during a blow molding
process by means of one or more injection needles extending from
the interior walls of the blow mold, as is know to the skilled
artisan.
[0038] In an embodiment of the present invention, flexible hollow
member (b), e.g., flexible hollow cushion 20, comprises means for
reversibly increasing pressure within the hollow interior, e.g.,
hollow interior 41, such as a pressure regulating valve (not shown)
that provides gaseous or fluid communication with the hollow
interior of cushion 20. A pressure regulating valve may be
incorporated into flexible hollow cushion 20 during or after the
molding processes by which it is formed. In the case of blow
molding, a pressure regulating valve may be placed into a recess
within the inner wall of the mold (the valve extending partially
from the recess). During the blow molding process, the valve
becomes incorporated into flexible hollow cushion 20. A pressure
regulating valve may be incorporated into the flexible hollow
member (b) after the molding process by means of art recognized
methods, which typically include plastic welding techniques, such
as thermal welding, radio frequency welding and solvent
welding.
[0039] During use of molded seat 2, the integral pressure
regulating valve (not shown) may be connected to a source of
pressurized gas (e.g., a pump or a reservoir connected to a pump,
not shown). An individual sitting on molded seat 2, may then
reversibly increase or decrease the pressure within flexible hollow
cushion 20 by means of the pressure regulating valve to suit their
own comfort.
[0040] Alternatively, the pressure regulating valve (not shown) may
be connected to a source of liquid, such as a reservoir of heat
exchange fluid, e.g., a mixture of water and propylene glycol. The
liquid can be either heated or cooled (e.g., by means of a heat
exchanger, not shown) and pumped into or cycled through flexible
hollow cushion 20 by means of one or more pressure regulating
valves, e.g., one or more integral pressure regulating valves (not
shown). The liquid, in addition to being either heated or cooled
may, for example, also be: (i) controllably pumped into cushion 20
to increase the pressure therein; (ii) cycled through cushion 20 to
maintain a selected level of pressure therein; or (iii)
controllably released from cushion 20 to decrease the pressure
therein. Heated liquid that may be introduced into the interior of
cushion 20 is typically heated to a temperature greater than or
equal to 25.degree. C., e.g., 30.degree. C., 50.degree. C. or
70.degree. C.. Cooled liquid that may be introduced into the
interior of cushion 20 is typically cooled to a temperature of less
than 25.degree. C., e.g., 20.degree. C., 15.degree. C. or
10.degree. C. An individual sitting on molded seat 2, may then, in
addition to reversibly increasing or decreasing the pressure within
flexible hollow cushion 20, also concurrently and reversibly adjust
the temperature of cushion 20 to suit their own comfort.
[0041] Flexible hollow cushion 20 may further comprise a fabric
covering on at least a portion of its outer surface in an
embodiment of the present invention. The fabric covering may be
pulled over cushion 20 after its formation. Alternatively, the
fabric covering may be formed on the outer surface of cushion 20
during its formation. When prepared by blow molding, a fabric
insert may be placed over at least a portion of the interior
surfaces of the mold. During the blow molding process, the parison
contacts and becomes fused with the fabric insert. When removed
from the mold, cushion 20 has an integral fabric covering on at
least a portion of its outer surface.
[0042] In an embodiment of the present invention, flexible hollow
member (b), e.g., flexible hollow cushion 20, has an integral film
on at least a portion of its outer surface. The integral film is
formed on the outer surface of the flexible hollow member by means
of an in-mold decoration process. The integral film is typically a
plastic film, e.g., a thermoplastic or thermoset plastic film, and
may be clear, tinted or opaque, e.g., pigmented. Additionally, the
integral film may have indicia, patterns and/or printing thereon.
Preferably the integral film is a thermoplastic film, e.g., a
thermoplastic polyurethane or polycarbonate film. The integral film
is typically incorporated into the outer surface of cushion 20
during the molding process, i.e., by means of an in-mold decoration
process. When prepared by blow molding, a film insert, e.g., a
thermoplastic polyurethane film insert, is typically placed in
contact with at least a portion of the interior surface of the
mold. During the blow molding process, the parison contacts and
becomes fused to the film insert. Upon removal from the mold,
flexible hollow cushion 20 has an integral film in and/or on at
least a portion of its outer surface.
[0043] The film insert may have indicia, patterns and/or printing
on at least a portion of one surface, e.g., on at least a portion
of its first and/or second surfaces. The first surface of the film
insert is that surface which contacts the inner surface of the
mold. The second surface of the film insert is opposite the first
surface, faces the interior of the mold, and comes into direct
contact with the parison during the blow molding process.
[0044] The exterior surface of flexible hollow cushion 20 may have
molded-in texture. Molded-in texture can serve to give cushion 20 a
leather-like appearance. The molded-in texture is typically formed
by a plurality of raised portions and/or recesses on and/or in the
interior surface of the mold in which cushion 20 is formed.
[0045] With reference to FIGS. 3 and 4, flexible cushion 20 is
fixedly attached to rigid seat support 10 by means of attachment
heads 44. Rigid seat support 10 has a plurality of perforations
having edges (not shown). Portions of flexible cushion 20 extend
through at least some of these perforations and form attachment
heads 44, the edges of the perforations become embedded in the
flexible material extending therethrough, and flexible cushion 20
is thus fixedly attached to rigid seat support 10.
[0046] A sectional representation through line A-A of an attachment
head 44 on rigid seat back support 17 of FIG. 3, is depicted as
attachment means 3 in FIG. 4. Rigid seat back support 17 has a
perforation 53 therein. Perforation 53 is defined by deformed edge
portions 50. Alternatively, perforation 53 may be defined by
non-deformed edge portions (not shown). A portion of flexible back
cushion 23, which abuts surface 56 of support 17, extends through
perforation 53 embedding edges 50 therein. The portion of flexible
back cushion 23 extending through perforation 53, further extends
out over surface 59 of support 17 and forms attachment head 44.
Attachment head 44 of FIG. 4 may be shaped by means of
corresponding depressions in the interior wall of the mold (not
shown).
[0047] In FIG. 4, the hollow interior 41 of flexible back cushion
23 is in communication with the hollow interior 62 of attachment
head 44. By selecting perforation 53 of smaller diameter and/or
flexible thermoplastic material (e.g., of back cushion 23) of
greater thickness, the flexible material extending through
perforation 53 may fuse together, effectively plugging perforation
53 and forming a substantially solid attachment head 44 (not
shown).
[0048] Attachment means 5 of FIG. 6 is similar to attachment means
3 of FIG. 4. Attachment head 45 of attachment means 5, however, is
substantially flush with second surface 59 of support 17. The flush
attachment head 45 is formed by means of the interior surface of
the mold being substantially flush or in abutment with second
surface 59 of support 17.
[0049] In addition to attachment means 3 and 5 of FIGS. 4 and 6,
flexible thermoplastic cushion 20 of molded seat 2 may be further
fixedly attached to rigid seat support 10 by attachment means
selected from fasteners, adhesives and combinations thereof.
Examples of fasteners that may be used in the present invention
include, but are not limited to, screws, e.g., sheet metal screws,
nuts and bolts, and metal rivets. Adhesives that may be used
include those that are known to the skilled artisan, e.g., epoxy
resin based adhesives.
[0050] As used herein and in the claims, the term "adhesives"
refers to: (i) adhesive materials that are separate from the rigid
support and the flexible thermoplastic member, e.g., epoxy resin
based adhesives; and (ii) cohesive adhesion between the rigid
support and the flexible thermoplastic member. The materials from
which each of the rigid support and the flexible thermoplastic
member may be selected such that cohesive adhesion therebetween
results from their mutual abutment. In an embodiment of the present
invention, the rigid support (a) is fabricated from steel,
poly(acrylonitrile-butadiene-styrene) or polycarbonate, and the
flexible hollow thermoplastic member (b) is fabricated from
thermoplastic polyurethane, and cohesive adhesion results from
their mutual abutment.
[0051] In an embodiment of the present invention, rigid seat
support 10 and molded flexible hollow cushion 20 are each
fabricated separately, and then cushion 20 is fixedly attached to
rigid support 10. Cushion 20 is positioned in abutting relation
with a first surface of rigid seat support 10, such that at least
some of the perforations 53 in support 10 are covered by cushion
20. Typically, at least those portions of cushion 20 that cover
perforations 53 are heated to soften the thermoplastic material of
cushion 20. Reduced pressure is formed on the side of support 10
that is opposite its first surface (i.e., the second surface of
support 10), and/or increased pressure is formed on the interior of
cushion 20. Those softened portions of cushion 10 are thus drawn
through perforations 53, embedding edges 50 in the thermoplastic
material extending therethrough, and forming attachment heads 44 on
the second surface of support 10.
[0052] In a preferred embodiment of the present invention, flexible
hollow cushion 20 is fixedly attached to rigid seat support 10
during the blow molding formation of cushion 20. Rigid seat support
10, having a plurality of perforations 53, is placed on one side of
the blow mold, its second surface facing the interior surface of
the mold wall, and its first surface facing the open interior of
the mold. A parison precursor of flexible hollow cushion 20 is blow
molded onto the first surface of rigid support 10, a portion of the
thermoplastic material of the parison extends through at least some
of perforations 53 of support 10 to form attachment heads 44. Edges
50 of perforations 53 become embedded in the thermoplastic material
of the parison extending therethrough, thereby fixedly attaching
flexible cushion 20 to rigid seat support 10.
[0053] To assist the extension of portions of the parison through
perforations 53, at least one of: (i) increased gaseous pressure is
provided on the interior of the thermoplastic parison; and (ii)
reduced gaseous pressure is provided on the second surface of rigid
support 10, thereby forcing (e.g., drawing and/or pushing) portions
of the thermoplastic parison through at least some of perforations
53. In an embodiment of the present invention, the parison is
extended through perforations 53 by the concurrent implementation
of methods (i) and (ii).
[0054] The rigid support (a) may have extensions, e.g., anchoring
extensions, which extend into the flexible thermoplastic hollow
member (b). Each extension has walls, e.g., side walls, a hollow
interior (e.g., a chamber), and at least one perforation in its
walls. Portions of the flexible hollow member (b) extend through
the perforations of the anchoring extensions and into the chamber
thereof. In an embodiment of the present invention, all of the
perforations of the rigid support (a) are located within the walls
of the anchoring extensions, and the flexible hollow member (b) is
fixedly attached to rigid support (a) by means of the anchoring
extensions. The anchoring extensions may have any desired shape,
but are typically substantially cylindrical.
[0055] In FIG. 5, a sectional view of an anchoring extension 68
extending into flexible back cushion portion 23 is depicted.
Extension 68 has walls 79 and a perforation 71. Perforation 71 has
edges 82 which are embedded in the flexible thermoplastic material
of cushion 23 which extends therethrough. The flexible
thermoplastic material of cushion 23 extending through perforation
71 forms attachment head 77 within chamber 65 of extension 68.
Rigid back support 17 has a perforation 74 therein which is in
communication with chamber 65 of extension 68. Perforation 74 can
be used to form a vacuum within chamber 65, to assist in drawing
attachment head 77 therein during molding operations, e.g., blow
molding. To prevent attachment head 77 from bursting during the
blow molding process, a reversibly retractable core pin (not shown)
may be extended from the interior wall of the mold through
perforation 74 into chamber 65 to provide a limiting surface
against which attachment head 77 abuts during its formation, as is
known to the skilled artisan. While anchoring extension 68 is
depicted as having only one perforation 71 in FIG. 5, it may have a
plurality of perforations through which the flexible material of
cushion 23 extends to form additional attachment heads within
chamber 65.
[0056] An advantage of using anchoring extensions to fixedly attach
cushion 20 to rigid support 10 is the recession and accompanying
protection that is afforded attachment head 77 within chamber 65.
After formation of molded seat 2, a thermosetting polymer
composition, e.g., a two-pack epoxy or polyurethane composition,
can be introduced into chamber 65 by means of perforation 74. The
introduced thermosetting polymer composition at least partially
fills chamber 65 and serves to protect and hold attachment head 77
in place.
[0057] In an embodiment of the present invention, rigid support (a)
has edges which are at least partially embedded in portions of
flexible hollow member (b) that are wrapped there around
(wrap-around attachment means). A sectional representation of a
wrap-around attachment means 8 is depicted in FIG. 7. With further
reference to FIG. 7, edge portion 85 of rigid support 17 (also
shown within highlighted area 88 of FIG. 3) has an extension 91
which is embedded in the flexible thermoplastic material of back
cushion 23. Such wrap-around attachment means are preferably formed
during the blow molding formation of flexible cushion 20 (including
back cushion portion 23). Wrap-around attachment means, such as
attachment means 8 of FIG. 7, serve to further fixedly attach
flexible hollow member (b) to rigid support (a) of the molded
article of the present invention. In another embodiment of the
present invention (not shown), extension 91 of wrap-around
attachment means 8 is not present, and edge portion 85 is beveled
or chamfered (not shown). The beveled edge portion of the rigid
support (a) is at least partially embedded in portions of the
thermoplastic material of flexible hollow member (b) that are
wrapped there around.
[0058] The rigid support (a) of the molded article of the present
invention may be solid or hollow. In an embodiment of the present
invention, the rigid support (a) is a rigid hollow support (e.g., a
rigid substantially tubular support) having an exterior (first)
surface, an internal (second) surface defining the hollow interior
of the hollow support, and a plurality of perforations. At least a
portion of the flexible hollow thermoplastic member (b) extends
through at least some of the perforations into the hollow interior
of the rigid hollow support (a).
[0059] Molded articles according to the present invention include,
but are not limited to: seats, such as chairs (e.g., indoor chairs
and outdoor chairs, such as patio furniture), bleachers, bicycle
seats, tractor seats and motor cycle seats; cushioned panels, such
as cushioned wall panels and cushioned door panels; and automotive
air-bags. Cushioned wall panels according to the present invention
include, for example, cushioned wall panels that may be use in
gymnasiums, e.g., on the gymnasium walls behind a basket ball
hoop.
[0060] The present invention has been described with reference to
specific details of particular embodiments thereof. It is not
intended that such details be regarded as limitations upon the
scope of the invention except insofar as and to the extent that
they are included in the accompanying claims.
* * * * *