Static structures (e.g. – buildings) – Composite prefabricated panel including adjunctive means – Sandwich or hollow with sheet-like facing members
Reexamination Certificate
1999-04-15
2001-01-09
Kent, Christopher T. (Department: 3635)
Static structures (e.g., buildings)
Composite prefabricated panel including adjunctive means
Sandwich or hollow with sheet-like facing members
C052S783120, C052S784100, C052S784150, C052S455000, C052S745190
Reexamination Certificate
active
06170224
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention is concerned with hollow structures such as multi-panel hollow doors having molded skins, and is more particularly concerned with improved paperboard cores for such doors.
Hollow doors with molded skins have become increasingly popular in recent years. Because the skins are flexible, it is necessary to provide some type of core, void filler, or separator between the skins to ensure the desired rigidity of the door. In doors having flat or flush skins without panels, the core may take the form of a simple multi-cellular structure (honeycomb) constituted of corrugated paperboard. However, a problem arises when a skin has panels defined by peripheral indentations, because the separation of the skins is not uniform.
One approach to solving this problem is to use a multi-cellular paperboard core in which the height of the cell walls varies to accommodate the indentations. However, this arrangement increases the complexity of core manufacture and door assembly. Another approach is to use a plurality of separate paperboard “build-ups” or pads between the skins, but this arrangement increases material requirements.
BRIEF DESCRIPTION OF THE INVENTION
The present invention provides a simpler, more economical solution to the problem of providing cores in hollow structures such as a multi-panel hollow doors.
In accordance with one aspect of the invention, a core is formed from a stack of paperboard plies in which adjacent plies are adhered to one another at predetermined positions in accordance with a predetermined pattern of adherence (e.g., a gluing pattern), such that the stack can be expanded in a direction perpendicular to the plies to form an elongated series of cells that can be readily placed longitudinally between transversely spaced panel indentations of a hollow door. In one embodiment, the pattern of adherence is such that portions of the stack remain unexpanded and form transversely extending wings between longitudinally spaced pairs of panel indentations, and also at the top and/or bottom of the door. In another embodiment, unexpanded end portions of the stack may be broken off to form pads which may be disposed between corresponding portions of the skins.
In a preferred form of multi-cellular paperboard core, each cell is hexagonal and has a pair of transversely spaced vertices, each vertex being formed by cell wall plies having juxtaposed end portions that are adhered to one another to form a tab. By virtue of discrete slitting of part of a vertex-forming ply, each tab is oriented to overlap an adjacent portion of that ply, which facilitates placement of the expanded core between transversely spaced panel indentations.
REFERENCES:
patent: 2765056 (1956-10-01), Tyree
patent: 3385002 (1968-05-01), Quinif
patent: 4130682 (1978-12-01), Lauko
patent: 4583338 (1986-04-01), Sewell et al.
patent: 4811538 (1989-03-01), Lehnert et al.
patent: 5155959 (1992-10-01), Richards et al.
patent: 5167105 (1992-12-01), Isban et al.
patent: 5466211 (1995-11-01), Komarek et al.
patent: 5560168 (1996-10-01), Gagne et al.
patent: 5582571 (1996-12-01), Simpson et al.
patent: 5681641 (1997-10-01), Grigsby et al.
patent: 5690601 (1997-11-01), Cummings et al.
patent: 5875608 (1999-03-01), Quinif
Boyse George C.
Colombero Richard S.
Wierzbicki David J.
Dorsey Dennis L.
Greif Bros. Corporation
Kent Christopher T.
Vorys Sater Seymour and Pease LLP
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