Engineered Molded Fiberboard Panels and Methods of Making and Using the Same

• US 20090255205A1
• Filed: 03/27/2009
• Published: 10/15/2009
• Est. Priority Date: 03/28/2008
• Status: Active Grant

• Current Assignee: United States Department Of Health And Human Services (Government of the United States of America), Noble Environmental Technologies Corporation
• Original Assignee: Noble Environmental Technologies Corporation
• Inventors: Hunt, John F., Gu, Hongmei, Noble, Robert, Newburn, Timothy L., Mahoney, James F.
• Granted Patent: US 8,297,027 B2
• Time in Patent Office: Days
• US Class Current: 52/630
• CPC Class Codes: A47C 5/005 of paper, cardboard or similar pliable material
• CPC Class Codes: B27F 1/00 Dovetailed work; Tenons; Making tongues or grooves slotting B27F5/00; Groove- and- tongue jointed work; Finger- joints machines or devices for working mitred joints B27G5/00; cutting tools for cutting grooves or tenons B27G13/14
• CPC Class Codes: B27H 1/00 Bending wood stock, e.g. boards
• CPC Class Codes: B27N 5/00 Manufacture of non-flat articles
• CPC Class Codes: B32B 21/02 the layer being formed of fibres, chips, or particles , e.g. MDF, HDF, OSB, chipboard, particle board, hardboard
• CPC Class Codes: B32B 21/10 Next to a fibrous or filamentary layer
• CPC Class Codes: B32B 21/13 all layers being exclusively wood
• CPC Class Codes: B32B 2262/062 Cellulose fibres, e.g. cotton
• CPC Class Codes: B32B 2262/14 Mixture of at least two fibres made of different materials
• CPC Class Codes: B32B 2307/50 having particular mechanical properties
• CPC Class Codes: B32B 2307/546 Flexural strength; Flexion stiffness
• CPC Class Codes: B32B 2307/718 Weight, e.g. weight per square meter
• CPC Class Codes: B32B 2307/72 Density
• CPC Class Codes: B32B 2419/00 Buildings or parts thereof walls, panels B32B2607/00
• CPC Class Codes: B32B 3/00 Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar shape; Layered products comprising a layer having particular features of form
• CPC Class Codes: B32B 3/10 characterised by a discontinuous layer, i.e. formed of separate pieces of material
• CPC Class Codes: B32B 3/12 characterised by a layer of regularly- arranged cells, e.g. a honeycomb structure
• CPC Class Codes: B32B 3/28 characterised by a layer comprising a deformed thin sheet , i.e. the layer having its entire thickness deformed out of the plane, e.g. corrugated, crumpled B32B29/08 takes precedence
• CPC Class Codes: B32B 38/0004 Cutting, tearing or severing, e.g. bursting; Cutter details cutting in general B26D; laminating combined with punching or perforating B32B38/04; removing all or part of the layers B32B38/10; cutting in combination with laying up and registration B32B38/185 takes precedence
• CPC Class Codes: B32B 5/022 Non-woven fabric
• CPC Class Codes: B32B 5/22 : characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed layer formed of natural mineral fibres or particles next to a foam layer B32B19/047, next to a layer made of particles B32B19/048, or next to a fibrous or filamentary layer B32B19/06; paper layer or cardboard layer next to a paper layer or cardboard layer B32B29/005, next to a foam layer B32B29/007, next to a fibrous or filamentary layer B32B29/02, or next to a particulate layer B32B29/04
• CPC Class Codes: B32B 5/26 : another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: B32B 7/05 : the layers not being connected over the whole surface, e.g. discontinuous connection or patterned connection using interposed adhesives or bonding materials applied in spaced arrangements B32B7/14
• CPC Class Codes: D21J 1/04 : Pressing
• CPC Class Codes: D21J 1/16 : Special fibreboard
• CPC Class Codes: E04C 2/16 : of fibres, chips, vegetable stems, or the like
• CPC Class Codes: E04C 2/322 : with parallel corrugations
• CPC Class Codes: E04C 2/3405 : spaced apart by profiled spacer sheets
• CPC Class Codes: E04C 2/365 : by honeycomb structures
• CPC Class Codes: E04C 2002/3455 : with trapezoidal corrugations
• CPC Class Codes: E04F 13/16 : of fibres or chips, e.g. bonded with synthetic resins , or with an outer layer of fibres or chips E04F13/0864 takes precedence
• CPC Class Codes: E04F 2203/04 : comprising a plurality of internal elongated cavities arranged in substantially parallel rows
• CPC Class Codes: E04F 2203/08 : with a plurality of grooves or slits in the back side, to increase the flexibility or bendability of the elements
• CPC Class Codes: Y10T 156/1052 : with cutting, punching, tearing or severing
• CPC Class Codes: Y10T 156/1062 : Prior to assembly
• CPC Class Codes: Y10T 156/1075 : of plural laminae from single stock and assembling to each other or to additional lamina
• CPC Class Codes: Y10T 428/1303 : Paper containing [e.g., paperboard, cardboard, fiberboard, etc.]
• CPC Class Codes: Y10T 428/1348 : Cellular material derived from plant or animal source [e.g., wood, cotton, wool, leather, etc.]
• CPC Class Codes: Y10T 428/236 : Honeycomb type cells extend perpendicularly to nonthickness layer
• CPC Class Codes: Y10T 428/24083 : Nonlinear strands or strand-portions
• CPC Class Codes: Y10T 428/24149 : Honeycomb-like
• CPC Class Codes: Y10T 428/24165 : Hexagonally shaped cavities
• CPC Class Codes: Y10T 428/24314 : Slit or elongated
• CPC Class Codes: Y10T 428/24694 : Parallel corrugations

Abstract

A fiberboard panel is formed from at least one corrugated sheet of molded cellulose fiber material having alternating ribs and grooves. Spaced slits are cut through the ribs on one face of the sheet and terminate short of the opposite face so as to form at least one slotted portion of more flexibility which may be bent to form a curve. The corrugated sheet is sandwiched between two flat sheets of the same material to form a composite panel. The corrugated sheet or panel is formed by a wet processing method including successive cold and hot press steps in which a wet mat is pressed between an opposing perforated platen and non-perforated, elastomeric material platen of cross-sectional shape substantially matching the desired panel shape and dimensions.

Claims

1. A panel, comprising:

an elongated sheet of molded fiberboard material of corrugated shape having opposite first and second faces and opposite side edges, each face having a plurality of alternating, longitudinally extending ribs and grooves extending along the length of the sheet, the ribs on the first face each having a first peak and the ribs on the second face each having a second peak facing in the opposite direction to the first peaks;

the sheet having at least one slotted portion which has a plurality of spaced slits cut through the ribs of at least one face and terminating short of the opposite face; and

the panel being formed into at least one curve at said one, slotted portion.

2. The panel of claim 1, wherein the sheet has a plurality of spaced slotted portions.

3. The panel of claim 2, wherein the slotted portions extend alternately through the first face and the second face of the sheet.

4. The panel of claim 1, wherein the slotted portion extends along at least a substantial portion of the length of the sheet.

5. The panel of claim 1, wherein the slits are at a constant spacing.

6. The panel of claim 1, wherein at least some of the slits are at a first spacing and other slits are at a second spacing different from the first spacing.

7. The panel of claim 1, wherein at least some of the slits are at a variable spacing.

8. The panel of claim 1, wherein the slits are parallel and extend perpendicular to the ribs.

9. The panel of claim 1, wherein the slits extend diagonally at an angle to the ribs.

10. The panel of claim 1, wherein the slits extend radially.

11. The panel of claim 10, wherein spaced slotted portions are provided along the length of the sheet, each slotted portion having a set of radially arranged slits, and alternating slotted portions have radial slits centered on opposite sides of the sheet.

12. The panel of claim 10, wherein spaced slotted portions are provided alternately on opposite sides of the sheet along the length of the sheet, the alternating slotted portions on opposite faces having radial slits centered on opposite sides of the sheet.

13. The panel of claim 1, wherein the sheet is formed with a curve at the slotted portion with the slotted face of the sheet facing inward.

14. The panel of claim 13, wherein the slots are closed at the peaks of the ribs on the inwardly curved face of the sheet.

15. The panel of claim 13, wherein the slots are closed with adhesive at least at the peaks of the ribs on the inwardly curved face of the sheet.

16. The panel of claim 1, wherein the sheet is formed from at least one cellulose fiber material.

17. The panel of claim 16, wherein the sheet is formed from a mixture of bovine processed fiber (BPF) and old newspaper (ONP).

18. A construction panel, comprising:

a first elongated sheet of molded fiberboard material of corrugated shape having opposite first and second faces and opposite side edges, each face having a plurality of alternating, longitudinally extending ribs and grooves extending along the length of the sheet, the ribs on the first face each having a first, flat peak and the ribs on the second face each having a second, flat peak facing in the opposite direction to the first peaks, the opposing first and second flat peaks forming opposing faces of the sheet, each first peak being connected to adjacent second peaks by angled webs forming opposite side faces of ribs;

the fiberboard material being formed from a mixture of at least two different cellulose fibers, one of the fibers comprising bovine processed fiber (BPF); and

the peaks on each face having a constant center to center spacing in the range from three inches to six inches and the rib height being in the range from 0.75 inches to 3 inches.

19. The panel of claim 18, wherein the angle of each web is 45 degrees.

20. The panel of claim 18, further comprising first and second outer flat sheets of molded fiberboard material secured to the outer faces of the first peaks and the second peaks, respectively, to form a multi-layer panel.

21. The panel of claim 18, further comprising a second, identical sheet of corrugated fiberboard material secured to the first sheet with opposing inner peaks of the two sheets adhered together, a first flat sheet of molded fiberboard material secured to the outer peaks of the first corrugated sheet and a second flat sheet of molded fiberboard material secured to the outer peaks of the second corrugated sheet.

22. The panel of claim 18, wherein a plurality of spaced slots are cut through the ribs on at least the first face of the sheet along at least part of the length of the sheet, each slot terminating short of the second peaks.

23. A method of molding a fiberboard panel in a corrugated shape, comprising the steps of:

hydropulping a furnish of cellulose fiber material into a water solution and mixing to separate the fibers into a pulp;

pouring the pulp onto an upper surface of a perforated mold screen in a former box, the screen having a corrugated shape of alternating ribs and grooves corresponding to a predetermined panel shape;

removing water from the pulp through the mold screen by applying a vacuum to the lower surface of the screen to leave a wet fiber mat on the screen;

removing the sides of the box and transferring the mold screen carrying the wet fiber mat longitudinally into a cold press between upper and lower platens of the press;

placing the mold screen onto a perforated lower platen of the press which is of shape corresponding to the mold screen shape;

moving an upper, non-porous platen of elastomeric material having a shape matching that of the lower platen and mold screen into engagement with an upper surface of the wet fiber mat to close the cold press;

pressing the opposing upper and lower platens towards each other to squeeze the wet fiber mat between the platens and squeeze water out of the mat through the openings in the mold screen and lower platen;

separating the platens and transferring the mold screen and fiber mat onto a perforated lower platen of a hot press having an upper platen of non-porous elastomeric material substantially identical to the upper elastomeric platen of the cold press, the upper and lower platens of the hot press having a cross-sectional shape similar to that of the upper and lower platens of the cold press;

closing the hot platens on the cold-pressed wet mat and applying pressure and heat to the mat to remove additional water by squeezing and vaporization until the mat has reached a desired densification and is substantially moisture free; and

separating the hot platens and removing the mold screen and finished panel from the hot press.

24. The method of claim 23, further comprising cutting a series of spaced slits through the ribs on a first face of the finished panel to form at least one slotted portion along at least part of the length of the panel, each slit terminating short of the opposing, second face of the panel.

25. The method of claim 24, further comprising bending the panel at the slotted portion to form a curve.

26. The method of claim 25, wherein the panel is bent with the first face and slots facing inward into the curve and the second, unslotted face facing outward.

27. A method of forming a fiberboard panel having at least one curve, comprising:

hydropulping cellulose fibers and water to form a slurry;

pouring the slurry over a corrugated form having alternating ribs and grooves corresponding to a predetermined corrugated panel shape;

removing water from the slurry to form a mat having a shape corresponding to the form shape;

pressing the mat to remove at least some water from the mat;

hot pressing the formed mat to remove at least substantially all of the water from the mat, forming a corrugated panel of bonded cellulose material;

cutting a series of slits along at least part of the length of the panel to form a slotted panel portion, the slits extending through the ribs on a first face of the panel and terminating short of the peaks of the ribs on an opposite, second face of the panel; and

bending the panel at the slotted panel portion to form a curve.

28. The method of claim 27, wherein the panel is bent so that the slots are on the inside of the curve.

29. The method of claim 28, wherein the panel is bent until the inner ends of the slits close together.

30. The method of claim 28, wherein adhesive is placed at the outer end of each slit to seal the outer end of the slit shut when the curve is formed.