Assembly including a compression-molded, composite panel having a cellulose-based core and a hinged mounting flange

Abstract

An assembly including a compression-molded, composite panel having first and second outer layers of fiber-reinforced thermoplastic material, first and second sheets of thermoplastic adhesive and a core of cellulose-based material is provided. The core has first and second portions positioned between the outer layers. The second outer layer is bonded to the core by the second sheet by press molding. The first outer layer includes a first portion bonded to the first portion of the core by the first sheet by press molding and a second portion bonded to the second portion of the core to form a mounting flange pivotally connected to the first portion of the first outer layer. A component is mounted to the flange to pivot with the flange. A living hinge allows the flange and the mounted component to pivot between different use positions relative to the first portion of the first outer layer.

Claims

1. An assembly comprising: a compression-molded, composite panel including first and second outer layers of fiber-reinforced thermoplastic material, first and second sheets of thermoplastic adhesive and a core of cellulose-based material and having first and second portions positioned between the outer layers, the first portion having a plurality of cavities and the second portion being substantially free of cavities, wherein the second outer layer is bonded to the core by the second sheet by press molding and the first outer layer includes a first portion bonded to the first portion of the core by the first sheet by press molding and a second portion bonded to the second portion of the core to form a mounting flange pivotally connected to the first portion of the first outer layer; a component mounted to the mounting flange to pivot with the mounting flange; and a living hinge which allows the mounting flange and the mounted component to pivot between different use positions relative to the first portion of the first outer layer wherein the mounting flange is formed by a crushed portion of the composite panel adjacent the living hinge to form a depression which receives the component.

2. The assembly as claimed in claim 1, further comprising at least one fastener for fastening the component to the mounting flange.

3. The assembly as claimed in claim 2, wherein each fastener is a threaded fastener and wherein the component includes a threaded part to hold the threaded fastener to the component.

4. The assembly as claimed in claim 3, wherein the mounting flange includes at least one hole which extends completely through the mounting flange, wherein each fastener is externally threaded, wherein the threaded part includes an internally threaded hole and wherein each fastener extends through its corresponding hole in the mounting flange and is threadedly secured within its internally threaded hole.

5. The assembly as claimed in claim 1, further comprising a substantially continuous carpet layer bonded to an upper surface of the first outer layer including the first and second portions of the first outer layer to at least partially form a carpeted composite panel having a carpeted mounting flange.

6. The assembly as claimed in claim 5, wherein the living hinge includes a portion of the carpet layer.

7. The assembly as described in claim 1 wherein the first outer layer is made out of polymeric material and wherein the living hinge is at least partially made out of the polymeric material.

8. The assembly as claimed in claim 1, further comprising a second living hinge which facilitates or allows the mounting flange and the mounted component to pivot between the different use positions.

9. The assembly as claimed in claim 8, further comprising a substantially continuous carpet layer bonded to an outer surface of the first outer layer including the first and second portions of the first outer layer to at least partially form a carpeted composite panel having a carpeted mounting flange.

10. The assembly as claimed in claim 9, wherein each of the first and second living hinges includes a portion of the carpet layer.

11. The assembly as claimed in claim 1, wherein a portion of the mounted component has a reduced thickness to form a depression which receives the mounting flange.

12. The assembly as claimed in claim 5, wherein a portion of the mounted component has a reduced thickness to form a depression which receives the carpeted mounting flange and wherein thickness of the carpeted mounting flange is substantially equal to depth of the depression.

13. The assembly as claimed in claim 5, wherein the first outer layer including the first and second portions is a fiber-reinforced, thermoplastic layer.

14. The assembly as claimed in claim 13, wherein the carpet layer is a thermoplastic carpet layer and wherein the thermoplastic of the first outer layer including the first and second portions and the carpet layer is polypropylene.

15. The assembly as claimed in claim 1, wherein the composite panel has a thickness in the range of 5 to 25 mm.

16. The assembly as claimed in claim 1, wherein the first outer layer has a load bearing surface.

17. The assembly as claimed in claim 1, wherein the core is a cellular core.

18. The assembly as claimed in claim 1, wherein the core has a honeycomb structure.

19. A vehicle assembly comprising: a compression-molded, composite panel including first and second fiber-reinforced thermoplastic, outer layers, first and second sheets of thermoplastic adhesive and a core of cellulose-based material and having first and second portions positioned between the outer layers, the first portion having a plurality of cavities and the second portion being substantially free of cavities, wherein the second outer layer is bonded to the first portion of the core by the second sheet by press molding and the first outer layer has an outer surface and includes a first portion bonded to the first portion of the core by the first sheet by press molding and a second portion bonded to the second portion of the core to form a mounting flange pivotally connected to the first portion of the first outer layer; a component mounted to the mounting flange to pivot with the mounting flange within an interior of a vehicle; and a living hinge which allows the mounting flange and the mounted component to pivot between different use positions relative to the first portion of the first outer layer wherein the mounting flange is formed by a crushed portion of the composite panel adjacent the living hinge to form a depression which receives the component.

20. A vehicle floor panel assembly comprising: a compression-molded, composite panel including first and second fiber-reinforced thermoplastic, outer layers, first and second sheets of thermoplastic adhesive and a core of cellulose-based material and having first and second portions positioned between the outer layers, the first portion having a plurality of cavities and the second portion being substantially free of cavities, wherein the second outer layer is bonded to the core by the second sheet by press molding and the first outer layer has a load-bearing surface and includes a first portion bonded to the first portion of the core by the first sheet by press molding and a second portion bonded to the second portion of the core to form a mounting flange pivotally connected to the first portion of the first outer layer; a component mounted to the mounting flange to pivot with the mounting flange in an interior of a vehicle; and a living hinge which allows the mounting flange and the mounted component to pivot between different use positions relative to the first portion of the first outer layer wherein the mounting flange is formed by a crushed portion of the composite panel adjacent the living hinge to form a depression which receives the component.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a side sectional view showing various separate layers of a prior art stack of thermoplastic-based layers of material;

(2) FIG. 2 is a top perspective sectional view of the stack of FIG. 1 after compression molding;

(3) FIGS. 3 and 4 are side views, partially broken away and in cross section, of a prior art sandwich-type composite panel having a living hinge and method of making the living hinge;

(4) FIG. 5 is an environmental view, partially broken away, of a carpeted automotive vehicle load floor including a pair of carpeted, sandwich-type, compression-molded, composite panel assemblies each being constructed in accordance with at least one embodiment of the present invention;

(5) FIG. 6 is a side view, partially broken away and in cross section, of one embodiment of one of the panel assemblies taken along lines 6-6 of FIG. 5;

(6) FIG. 7 is a view, similar to the view of FIG. 6, but showing a second embodiment of one of the panel assemblies taken along lines 7-7 of FIG. 5;

(7) FIG. 8 is a view, similar to the views of FIGS. 6 and 7, but showing a third embodiment of one of the panel assemblies taken along lines 8-8 of FIG. 5;

(8) FIG. 9 is a side sectional view showing a stack of various separate sheets or layers of thermoplastic-based and cellulose-based material prior to being compression molded into a composite component having a sandwich structure;

(9) FIG. 10 is a top perspective view, partially broken away and in cross section, of the composite component of FIG. 9;

(10) FIG. 11 is a view similar to the view of FIG. 10 but providing a bottom perspective view;

(11) FIG. 12 is a top plan view, partially broken away, of a reinforced thermoplastic skin having substantially parallel, visible fibers; and

(12) FIG. 13 is a view similar to the view of FIG. 12 but with substantially randomly oriented visible fibers.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

(13) As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

(14) Referring now to the FIGS. 5, 6, 7, and 8 different embodiments of an assembly including a compression-molded composite panel with a hinged mounting flange are provided. In one example embodiment, a carpeted automotive vehicle load floor, generally indicated at 13, includes a pair of carpeted, compression-molded, sandwich-type, composite hinged panel assemblies, generally included at 10. In one example embodiment, the assembly 10 (FIG. 6) has a single living hinge 12. In a second example embodiment, the assembly 10 (FIG. 7) has a single living hinge 12 and an elongated top decorative depression 46. In a third example embodiment, the assembly 10 (FIG. 8) has a pair of spaced apart living hinges 12. However, it is to be understood that one or more panel assemblies 10 constructed in accordance with at least one embodiment of the present invention may be used in a wide variety of environments besides the automotive vehicle environment of FIG. 5.

(15) Each panel of the panel assembly 10 (FIGS. 6, 7 and 8) is typically manufactured by providing a stack of materials located or positioned within a mold. The stack includes first and second reinforced thermoplastic skins or outer layers 20 and 22, respectively, a core having a large number of cavities such as a thermoplastic cellular core 24 disposed between and bonded to the skins 20 and 22 by press molding within the mold. A substantially continuous covering or carpet layer 26 made of thermoplastics material covers and is bonded to the first skin 20 which provides a top carpeted support surface. The skins 20 and 22 are heated typically outside of the mold to a softening temperature. The mold is preferably a low-pressure, compression mold which performs a thermo-compression process on the stack of materials.

(16) The outer skin 20 is divided into a first portion bonded to a first portion of the core 24 and a second portion bonded to a second portion 30 of the core 20 which is substantially free of cavities (i.e. is substantially solid) to at least partially form a mounting flange 28 pivotally connected to the first portion of the skin 20 by the living hinge 12. In other words, as shown in FIGS. 6, 7 and 8, the outer skin 20 is divided into a first portion bonded to the first portion of the core 20 (which has cavities) and a second portion bonded to a second portion of core 20 (which is substantially solid) to at least partially form the mounting flange 28 pivotally connected to the first portion of the skin 12 by the living hinge(s) (12 or 12).

(17) The assembly 10 also includes a component such as a thermoplastic component, generally indicated at 32, which is mounted to the mounting flange 28 to pivot with the mounting flange 28 about the living hinge 12. The living hinge 12 allows the mounting flange 28 and the mounted component 32 to pivot between different use positions relative to the first (right most as shown in FIGS. 6-8) portion of the first layer 20.

(18) A portion 36 of the thermoplastic carpet layer 26 covers and is bonded to an upper surface of a plastic part 34 of the component 32 to provide an upper carpeted support surface. An intermediate portion of the layer 26 at least partially forms the living hinge 12. The living hinge 12 allows the carpeted mounting flange 28 to pivot between the different use positions.

(19) The assembly 10 (of FIGS. 6, 7 and 8) may also include at least one threaded or non-threaded fastener for fastening the component 32 to the mounting flange 28. The fastener may be any of various devices for fastening the component 32 to the mounting flange 28 such as an externally threaded screw 40 or bolt. The screw 40 is characterized by a helical ridge, or external thread, wrapped around a cylinder. The screw threads mate with a complementary thread or internal thread in the part 34. The internal thread may be in the form of a nut or an object that has the internal thread formed into it. The screw thread may also cut a helical groove in the softer material of the part 34 as the screw 40 is inserted. The head of the screw 40 is preferably decorative.

(20) Each screw 40 may be made from a wide range of materials, with steel being perhaps the most preferred, in many varieties. Where great resistance to corrosion is required, stainless steel, titanium, brass, bronze, monel or silicon bronze may be used. Galvanic corrosion of dissimilar metals can be prevented by a careful choice of material.

(21) Some types of plastic, such as nylon or polytetrafluoroethylene (PTFE), can be threaded and used for fastenings requiring moderate strength and great resistance to corrosion or for the purpose of electrical insulation. A surface coating may be used to protect the fastener from corrosion (e.g. bright zinc plating for steel screws), to impart a decorative finish (e.g. jappaning) or otherwise alter the properties of the base material. Selection criteria of the screw materials include temperature, required strength, resistance to corrosion, joint material and cost.

(22) The panel assembly 10 may also include a plastic mounted support or bar 34 which extends across the width of the storage area under the assembly 10 to support the component 32 and the panel of the assembly 10 at the living hinge(s) 12 or 12.

(23) The carpet layer 26 may be a resin carpet and the resin may be polypropylene. The carpet layer 26 may be made of a woven or nonwoven material (typically of the carpet type).

(24) Referring now to FIG. 7, a second embodiment of an assembly is generally indicated at 10. The assembly 10 is substantially identical to the assembly 10 of FIG. 6 but includes a top and relatively deep decorative depression 46 formed during the compression molding process by a projection supported or suspended at the inner mold surface of an upper mold half.

(25) Referring now to FIG. 8, a third embodiment of an assembly is generally indicated at 10. The parts of the assembly 10 which are the same in either structure and/or function to the parts of FIGS. 6 and 7 have the same reference number. In general, the assembly 10 of FIG. 8 differs from the assembly of FIG. 6 by having two living hinges 12 with a mounting flange 28 and a decorative depression 46 to further facilitate or allow the carpeted mounting flange 28 and mounted component 32 to pivot between different use positions. Also, while shown solid, the part 34 may be hollow to provide a component 32 which may be lighter in weight than the solid part 34 of FIGS. 6, 7, and 8.

(26) The cellular core 24 may be a honeycomb core. In this example, the cellular core 24 has an open-celled structure of the type made up of tubes or a honeycomb, and it is made mainly of polyolefin and preferably of polypropylene. It is also possible to use a cellular structure having closed cells of the foam type.

(27) The member or component 32 may be made of a different material(s) to which the portion 36 of the carpet layer 26 is bonded.

(28) Each of the skins 20 and 22 of each of the assemblies 10 may be fiber reinforced. The thermoplastic of the skins 20 and 22, the covering carpet layer 26 and the core 24 may be polypropylene. At least one of the skins 20 and 22 may be a woven skin, such as polypropylene skin. Each of the skins 20 and 22 may be reinforced with fibers, e.g., glass fibers, carbon fibers or natural fibers. At least one of the skins 20 and 22 may advantageously be made up of woven glass fiber fabric and of a thermoplastics material.

(29) Each resulting hinged panel assembly 10 may have a thickness in the range of 5 to 25 mm. A depression 38 formed in the part 34 and in which the mounting flange 28 is secured may have a depth in the range of 2 to 10 mm.

(30) In one example method of making the hinged panel assembly 10 including the mounting flange 28, stacks of material are pressed in a low pressure, cold-forming mold. With respect to a first part of the hinged panel assembly 10, the stack is made up of the first skin 20, the cellular core 24, the second skin 22 and a portion of the covering layer 26, and the stack is pressed at a pressure lying in the range of 1010.sup.5 Pa. to 3010.sup.5 Pa. The first and second skins 20 and 22 are preferably pre-heated to make them malleable and stretchable. Advantageously, in order to soften the first and second skins 20 and 22, respectively, heat is applied to a pre-assembly constituted by the stack made up of at least the first skin 20, of the cellular core 24, and the second skin 22 so that, while the first part of the panel of the assembly 10 is being formed in the mold, the first and second skins 20 and 22 have a forming temperature lying approximately in the range of 160 C. to 200 C., and, in this example, about 180 C. In like fashion, the mounting flange 28 may be formed. However, in forming the mounting flange 28, the living hinge 12 (or hinges 12) may be formed by performing the method of the above-noted patent application entitled Method of Making a Sandwich Type Composite Panel Having a Living Hinge and Panel Obtained by Performing the Method.

(31) The covering carpet layer 26 is substantially continuous and may be formed from separate pieces of thermoplastic resin carpet which are subsequently bonded or fused together, such as by heat and/or pressure to carpet the entire top support surface of the hinged panel assembly 10.

(32) In summary, FIGS. 6, 7 and 8 show first, second and third embodiments, respectively, of a carpeted, sandwich-type, composite hinged panel assembly 10. The assemblies 10 have basically the same structure and function except in the first embodiment of FIG. 6 a single living hinge 12 is provided, in the second embodiment a single living hinge 12 with a deep decorative groove 46 are provided and in the third embodiment a pair of living hinges 12 with a shallow depression 46 are provided.

(33) Referring now to the FIGS. 10 and 11, another embodiment of a compression-molded, sandwich-type composite panel, generally indicated at 110, is shown. FIG. 9 shows a stack of thermoplastic-based and cellulose-based sheets or layers of material prior to the stack being compression molded into the composite panel or component 110. It is to be understood that one or more of such panels constructed in accordance with at least one embodiment of the present invention may be used in a wide variety of environments. For example, the panel 110 may be a load-bearing vehicle component as shown or an interior trim component.

(34) The panel 110 is typically manufactured via a thermo-compression process by providing the stack of material located or positioned within a low pressure, thermo-compression mold. As shown in FIG. 9, the stack includes first and second reinforced thermoplastic skins or outer layers 112 and 114, respectively, a cellulose-based core having a large number of cavities such as a paper or cardboard cellular core 116 disposed between and bonded to plys or films or sheets of hot-melt adhesive (i.e. thermoplastic adhesive) 118 and 120 which, in turn, are disposed between and bonded to the skins 112 and 114 by the press or compression molding. The sheets 118 and 120 may be bonded to their respective skins 112 and 114 prior to the press molding or are preferably bonded during the press molding. The thermoplastic of the sheets 118 and 120 is typically compatible with the thermoplastic of the skins 112 and 114 so that a strong bond is formed therebetween. One or more other resins may also be included within the adhesive of the sheets 118 and 120 to optimize the resulting adhesive system. The adhesive system is not a solvent-based adhesive system.

(35) An optional substantially continuous covering or carpet layer, generally indicated at 122, made of thermoplastics material covers the first skin 112. The skins 112 and 114 and their respective sheets or film layers 118 and 120 (with the core 116 in between the layers 118 and 120) are heated typically outside of the mold (i.e. in an oven) to a softening temperature wherein the hot-melt adhesive becomes sticky or tacky. The mold is preferably a low-pressure, compression mold which performs a thermo-compression process on the stack of materials.

(36) The step of applying the pressure compacts and reduces the thickness of the cellular core 116 and top and bottom surface portions of the cellular core 116 penetrate and extend into the film layers 118 and 120 without penetrating into and possibly encountering any fibers located at the outer surfaces of the skins 112 and 114 thereby weakening the resulting bond. Often times the fibers in the skins 112 and 114 are located on or at the surfaces of the skins as shown by skins 112 and 112 in FIGS. 12 and 13, respectively, wherein the fibers are substantially parallel and randomly oriented, respectively.

(37) The carpet layer 122 may be a resin carpet and the resin may be polypropylene. The carpet layer 122 may be made of a woven or nonwoven material (typically of the carpet type).

(38) An optional bottom layer of the panel 110 comprises a decorative, noise-management, covering layer 124 bonded to the bottom surface of the panel 110 to provide sound insulation and an aesthetically pleasing appearance to the bottom of the panel 110 if and when the bottom of the panel 116 is exposed to a passenger of the vehicle or others. In other words, the covering layer 124 reduces the level of undesirable noise in a passenger compartment of the vehicle.

(39) The cellulose-based, cellular core 116 may be a honeycomb core. In this example, the cellular core has an open-celled structure of the type made up of a tubular honeycomb, and it is made mainly of cellulose and preferably of paper or cardboard. The sticky or tacky hot-melt adhesive extends a small amount into the open cells during the thermo-compression process. It is also possible to use a cellular structure having closed cells, a material, such as a wooden part, to which the top and bottom film layers 118 and 120, respectively, are bonded.

(40) Each of the skins 112 and 114 may be fiber reinforced. The thermoplastic of the sheets or film layers 118 and 120, the skins 112 and 114, and the covering layers 122 and 124 may be polypropylene. Alternatively, the thermoplastic may be polycarbonate, polyimide, acrylonitrile-butadiene-styrene as well as polyethylene, polyethylene terphthalate, polybutylene terphthalate, thermoplastic polyurethanes, polyacetal, polyphenyl sulphide, cyclo-olefin copolymers, thermotropic polyesters and blends thereof. At least one of the skins 112 or 114 may be woven skin, such as polypropylene skin. Each of the skins 112 and 114 may be reinforced with fibers, e.g., glass fibers, carbon fibers, aramid and/or natural fibers. At least one of the skins 112 and 114 can advantageously be made up of woven glass fiber fabric and of a thermoplastics material.

(41) The resulting panel 110 may have a thickness in the range of 5 to 25 mm.

(42) In one example method of making the panel 110, a stack of material may be pressed in a low pressure, cold-forming mold (not shown). The stack is made up of the first skin 112, the first film layer 118, the paper cellular core 116, the second film layer 120, the second skin 114 and the covering layers 122 and 124, and is pressed at a pressure lying in the range of 1010.sup.5 Pa. to 3010.sup.5 Pa. The first and second skins 112 and 114, and the first and second film layers 118 and 120 are preferably pre-heated to make them malleable and stretchable. Advantageously, in order to soften the first and second skins 112 and 114, and their respective film layers 118 and 120, respectively, heat is applied to a pre-assembly made up of at least the first skin 112, the first film layer 118, the paper cellular core 116, the second skin 114 and the second film layer 120 so that, while the panel 110 is being formed in the mold, the first and second skins 112 and 114 and the film layers 118 and 120 have a forming temperature lying approximately in the range of 160 C. to 200 C., and, in this example, about 180 C.

(43) The covering layer 122 is substantially continuous and may be formed from separate pieces of thermoplastic resin carpet which are subsequently bonded or fused together, such as by heat and/or pressure to carpet the entire top surface of the panel 110.

(44) The bottom layer 124 of the panel 110 may be made of a nonwoven scrim 124 of fine denier, spunbond thermoplastic (i.e., polypropylene and/or polyester or other thermoplastic compatible to the process) fibers in the form of a sheet and having a weight in a range of 8 to 100 gsm (i.e., grams per square meter). Preferably, the weight is in a range of 17 to 60 gms. Also, preferably, the denier is in a range of 1.8 to 2.2.

(45) The scrim 124 has an open mesh of nonwoven synthetic thermoplastic fibers including a plurality of adjacent openings. The scrim 124 both transmits light to the underlying layer and reflects light while reducing the level of undesirable noise from a different area of the vehicle. The scrim 124 may be manufactured in a color which is substantially the same, complements or is in contrast with the color of the upper carpet 122. Also, the panel 110 including the underlying scrim layer 124 and the carpet 122 can be made in a single compression molding step.

(46) While exemplary embodiments are described above, it is not intended that these embodiments 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. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.