LAYERED PANELS

Abstract

A composite panel exhibiting high flexural strength while reducing mass as compared with conventional composite panels is provided. The improved panel includes a rigid frame having outer edges defining a perimeter of the panel and inner edges defining a perimeter of a structural filler chamber, wherein the frame has a thickness at its outer edges that is narrower than at its inner edges; first and second sheet-like material layers bonded to opposite sides of the rigid frame to define, together with the inner edges of the rigid frame, a volume of the structural filler chamber; and a structural filler disposed in the chamber to provide compressive strength between the sheet-like material layers.

Claims

1. A composite panel, comprising: a rigid frame having outer edges that define a perimeter of the composite panel and inner edges defining a perimeter of a structural filler chamber, a thickness of the rigid frame being greater at the inner edges than at thinner outer edges; a first sheet-like material layer bonded with a first side of the rigid frame; a second sheet-like material layer bonded with an opposite second side of the rigid frame, the second sheet-like material layer having a flat top surface and ramped edge sections curved or sloped away from the top surface of the second sheet-like material and toward the thinner outer edges of the rigid frame, the first sheet-like material layer and the flat top surface of the second sheet-like material layer being substantially parallel and uniformly spaced apart and, together with the inner edges of the rigid frame, define the structural filler chamber; and a structure filler disposed in the structural filler chamber, the structural filler having a lower density than the rigid frame and the first and second sheet-like material layers, and a compressive strength sufficient to resist deformation of the sheet-like material layers when loads are applied to the sheet-like material layers in an area overlying the structural filler.

2. The composite panel of claim 1, wherein the rigid frame is a unitary component.

3. The composite panel of claim 2, wherein the rigid frame is made of a fiber reinforced thermoset composite.

4. The composite panel of claim 1, wherein the rigid frame is comprised of a first frame section defining a first opening and having a uniform thickness, and a second frame section defining a second opening, and wherein the first and second frame sections are joined together.

5. The composite panel of claim 1, wherein the first sheet-like material layer and the second sheet-like material layer each have a thickness that is less than 10% of the length of the sheet-like material layer and less than 10% of the width of the sheet-like material layer.

6. The composite panel of claim 1, wherein a first edge of the panel is curved upwardly and an opposite second edge of the panel is curved downwardly.

7. The composite panel of claim 4, wherein the first frame section includes an internal rib extending between opposite inner edges of the second opening.

8. The composite panel of claim 1, wherein the structural filler is a polymeric foam.

9. The composite panel of claim 8, wherein the structural filler has a density of from 20 kg/m.sup.3 to 30 kg/m.sup.3 and a compressive strength of from 50 kPa to 200 kPa.

10. The composite panel of claim 1, wherein the rigid frame is made of material having a modulus of elasticity of 800,000 psi to 2,500,000 psi and a modulus of rupture of 5,000 psi to 15,000 psi.

11. The composite panel of claim 10, wherein the rigid frame is made of wood or plastic.

12. The composite panel of claim 1, wherein each of the first and second sheet-like material layers is made of a laminate of paper or textile with melamine resin.

13. The composite panel of claim 1, wherein the structural filler has a honeycomb-like structure comprised of resin-impregnated aramid paper.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. 1 is an exploded view of a composite panel in accordance with this disclosure.

[0007] FIG. 2 is an illustration of one embodiment of the first sheet-like material layer of the composite panel.

[0008] FIG. 3 is an illustration of one embodiment of the second sheet-like material layer of the composite panel after it has been shaped during bonding to the rigid frame and structural filler insert.

[0009] FIG. 4 is an illustration of one embodiment of the composite panel having a front curved surface and back curved surface.

[0010] FIG. 5 is an illustration of one embodiment of the frame and the present invention.

[0011] FIG. 6 is an illustration of one embodiment of the filler insert of the present invention.

[0012] FIG. 7 is an illustration showing one embodiment of the sloped sides of the bond frame of the present invention.

[0013] FIG. 8 is an illustration of one embodiment of a bottom surface of the bond frame with upwardly-extending bond frame walls.

[0014] FIG. 9 is a cross-sectional view of one embodiment of the present invention with a gap space.

[0015] FIG. 10 is a prospective view of an alternative design using a rigid frame base section having an internal rib for added strength.

DETAILED DESCRIPTION

[0016] All illustrations of the drawings are for the purpose of describing selected versions of the disclosed panels and are not intended to limit the scope of the claims.

[0017] The disclosed composite panels are strong, lightweight, aesthetic and exhibit antimicrobial efficacy.

[0018] In reference to FIG. 1, a composite panel 100 is shown in an exploded configuration. Panel 100 includes first sheet-like material layer 10, a first frame section 20, a structural filler insert 30, a second frame section 40, and second sheet-like material layer 50.

[0019] As can be seen in FIG. 2, first sheet-like material layer 10 can be a thin, flat, planar sheet. The term “sheet-like” as used herein can mean a material having length and width dimensions that are much larger than the thickness of the material, and wherein the thickness is much less than the length and width of the material (e.g., thickness is less than 10%, less than 5% or less than 1% of the length and width of the sheet-like material layer), and wherein the thickness is uniform along the length and width of the sheet-like material.

[0020] The second sheet-like material layer can have a flat central surface 55 and curved or inclined edge surfaces 60, as shown in FIG. 3.

[0021] In accordance with an optional aspect of this disclosure, in certain applications, such as desktops, the composite panel can be provided with curved edges 56, 57. For example, a first edge could be curved downwardly from the front of a desktop to eliminate sharp edges where a user may wish to place their hand, and an upwardly curved rear edge that could prevent writing implements or other items from rolling off the desktop. Additionally, the curves provide added flexural strength without adding significant weight or cost, similar to the added strength of an angle iron as compared to a strap.

[0022] As shown in FIG. 5, first frame section 20 defines an opening 26. Outer edges of the first frame section 20 generally define the perimeter of the composite panel. For enhanced strength, first base section 20 can be provided with an internal rib 21 as shown in FIG. 10.

[0023] Shown in FIGS. 7 and 8 is the second frame section 40. Second frame section 40 can include sloped outer edges 44 and have inner edges 45 defining an opening 46.

[0024] Second frame section 40 and first frame section 20 together define a rigid frame. First frame section 20 and second frame section 40 can be separately fabricated components that are joined together (e.g., with adhesives or mechanical fasteners such as screws), or can be fabricated together as a unitary structural component, such as from fiber (e.g., glass fiber) reinforced thermoset composites.

[0025] Structural filler 30 (shown in FIGS. 1, 6 and 9) is disposed within a volume or chamber defined by inner edges 25, 45 of rigid frame sections 20 and 40 respectively, and by first and second sheet-like material layers 10 and 50. Structural filler 30 is a lightweight material that exhibits sufficient compressive strength to eliminate a need for strengtheners or other high density structural members while preventing deformation of layers 10 and 50 when forces are applied at areas overlying the structural filler. Suitable low density, high strength materials that can serve as structural filler 30 include various polymeric foams (e.g., polypropylene foams, polyurethane foams) and honey comb-life structures (e.g., resin-impregnated aramid paper) that have a density of from about 20 to about 30 kg/m.sup.3 and a compressive strength of from about 50 to 200 kPa.

[0026] The frame sections 20 and 40 (or rigid frame of unity structure) are rigid materials typically having a high modulus of elasticity (e.g., from about 800,000 psi to about 2,500,000 psi or higher) and a high modulus of rupture (from about 5,000 psi to about 15,000 psi or higher). Suitable materials include woods (e.g., douglas fir, sitka spruce, white pine, red pine, red oak, red maple, white oak, black walnut), plastics (e.g., ABS, acetal copolymers, acrylic polymers, nylon 6, polyamide-imide, polycarbonate, polyimide, polystyrene, etc.) and fiber reinforced composites (e.g., glass fiber reinforced polyimide). Frame section 20 and frame section 40 can be fabricated of the same material or different materials.

[0027] Sheet-like material layers 10 and 50 can be made of laminates of paper or textile with a melamine or other resin. Such laminates are sold under the trademarks or tradenames “Formica,” “Arborite,” “Micarta,” “Wilsonart” and “Consoweld.”

[0028] An advantage of the disclosed structure is that composite panels suitable for many office furniture applications can achieve suitable strength properties at a reduced weight (e.g., from about 1 lb/ft.sup.2 to about 10 lb/ft.sup.2).

[0029] The thickness of structural filler, and hence the distance or spacing between layers 10 and 50 can range from about 0.1 inches to about 1 inch (e.g., from about 0.25 inches to about 0.75 inches). The distance of overlap of layers 10 and 50, and sheet-like base section 20 from the peripheral edge inward can be from about 0.5 inches to 2 inches (e.g., from 0.5 inches to 1 inch).

[0030] Suitable adhesives for joining the components of the composite panel (e.g., bonding edges of layers 10 and 50 to sheet-like base 20) include various hot melt adhesives, thermoset adhesives, polyurethane adhesives, etc.

[0031] Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention.

[0032] While the present invention is described herein with reference to illustrated embodiments, it should be understood that the invention is not limited hereto. Those having ordinary skill in the art and access to the teachings herein will recognize additional modifications and embodiments within the scope thereof. Therefore, the present invention is limited only by the claims attached herein.