US 5,667,620 AGranted

Method for making a structual member

AssigneeNorth American Container Corporation

InventorsJohn M. Grigsby, Jeffrey C. Banks, John M. Grigsby, Jr.

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Abstract

A structural member formed from a billet, each member comprising a plurality of corrugated paperboard sheets bonded together with an adhesive and disposed between a core fibre layer, each core fibre layer comprising at least one ply of a fibreboard sheet, a pair of caps of a solid fibreboard sheet bonded to respective side faces of the paperboard sheet and to the respective edges of the core fibre layers. A method of manufacture is disclosed in which the billet is built up of corrugated paperboard sheets. The billet is then ripped into planks for use as a plank, board, or cleat, particularly as components for corrugated paperboard containers. A pallet made of planks and a pallet made of planar sheets cut from the billet are disclosed.

Claims3

Dependent claims

A method of manufacturing a structural member, comprising the steps of:

(a) applying adhesive to at least one exterior surface of a low density corrugated paperboard sheet having corrugations, said corrugated paperboard sheet defined by a fluted sheet attached to at least a planar paperboard sheet;
(b) stacking a plurality of the adhesive-coated corrugated paperboard sheets together to form a stack;
(c) bonding the stack of adhesive-coated corrugated paperboard sheets together to form a billet;
(d) ripping the billet at a predetermined width to make an elongated core plank having exposed corrugations on two opposing lateral sides;
(e) laminating a pair of caps of high density fibreboard sheet on the two opposing lateral sides of the core plank to cover the exposed corrugations of the stacked corrugated paperboard sheets for forming a capped plank for use as a structural member by cutting to a selected length.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application: 08/474,709Filed 7 Jun 1995 · division
Priority: 24 May 1993
Granted: 16 Sep 1997
Term ends: Not estimatedThe source records don’t support an estimate.

Classification47 codes

B32B 3/28
Characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or…
B31D 5/00
Multiple-step processes for making three-dimensional [3d] articles
B31F 1/0012
Of plates, sheets or webs: combined with making folding lines
B32B 29/002
Layered products comprising a layer of paper or cardboard: as the main or only constituent of a layer, which is next to another layer of the same…