U.S. patent application number 10/340240 was filed with the patent office on 2003-08-07 for self gapping wood based panels.
Invention is credited to Grant, David R..
Application Number | 20030145551 10/340240 |
Document ID | / |
Family ID | 27668928 |
Filed Date | 2003-08-07 |
United States Patent
Application |
20030145551 |
Kind Code |
A1 |
Grant, David R. |
August 7, 2003 |
Self gapping wood based panels
Abstract
A wood based panel having at least one spacer, spaced at
intervals or continuously, on a square edge in which the spacer
will deform or be forced into an adjacent panel when subjected to
linear expansion forces.
Inventors: |
Grant, David R.; (New
Liskeard, CA) |
Correspondence
Address: |
Price, Heneveld, Cooper,
DeWitt & Litton
695 Kenmoor, S.E.
Post Office Box 2567
Grand Rapids
MI
49501
US
|
Family ID: |
27668928 |
Appl. No.: |
10/340240 |
Filed: |
January 10, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60354471 |
Feb 5, 2002 |
|
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Current U.S.
Class: |
52/592.1 ;
52/592.2 |
Current CPC
Class: |
B27F 1/04 20130101; E04F
15/04 20130101; E04F 13/10 20130101; B27B 33/08 20130101; E04F
2201/01 20130101; E04F 2201/023 20130101 |
Class at
Publication: |
52/592.1 ;
52/592.2 |
International
Class: |
E04B 002/08; E04B
002/18; E04B 002/32; E04B 002/46 |
Claims
The invention claimed is:
1- A wood based panel for use in building comprising; spaced top
and bottom surfaces bounded by edges extending therebetween, the
width of said edges defining the thickness of said panel; at least
one of said edges including a spacer integral with and projecting
from said edge, at least at spaced intervals along said edge, said
spacer projecting from said edge a distance equal to a
predetermined desired spacing for said panels in order to avoid
problems associated with improper spacing of said panel from
adjacent panels, and said spacer having a thickness laterally of
its direction of projection which is narrower than the width of
said edge, said thickness being sufficient to give said spacer
enough strength to resist damage during handling and installation
of said panel, but leaving said spacer sufficiently weak or sharp
that said spacer will collapse or be pushed into an adjacent panel
under the pressure of linear expansion forces caused by expansion
of the wood materials of which said panel is made.
2- The wood based panel of claim 1, wherein said spacer is
continuous.
3- The wood based panel of claim 1, wherein said spacer is
interrupted by gaps.
4- The wood based panel of claim 1, wherein said spacer projects
from said edge a distance of from about {fraction (1/32)} to about
1/4 inch.
5- The wood based panel of claim 4, wherein said spacer has a
thickness of from about 2/3 of the panel thickness to about 0.1
inch.
6- The wood based panel of claim 4, wherein said spacer has a
thickness of from about 2/3 of the panel thickness to about 0.1
inch.
7- The wood based panel of claim 1, wherein said spacer projects
from said edge a distance of from about {fraction (1/16)} to about
1/8 inch.
8- The wood based panel of claim 1 having a thickness of from about
1/4 to about 13/4 inch.
9- The wood based panel of claim 8, wherein said spacer projects
from said edge a distance of from about {fraction (1/32)} to about
1/4 inch.
10- The wood based panel of claim 9, wherein said spacer has a
thickness of from about 2/3 of the panel thickness to about 0.1
inch.
11- The wood based panel of claim 9, wherein said spacer has a
thickness of from about 2/3 of the panel thickness to about 0.1
inch.
12- The wood based panel of claim 8, wherein said spacer projects
from said edge a distance of from about {fraction (1/16)} to about
1/8 inch.
13- The wood based panel of claim 1 having a thickness of from
about {fraction (7/16)} to about 7/8 inch.
14- The wood based panel of claim 1, wherein the wood based panel
has four edges with spacers on two adjacent edges.
15- The wood based panel of claim 1, wherein the panel has four
edges, with a tongue and a groove on opposite edges, said spacer
being on only one edge, extending between the tongue edge and
groove edge.
16- A method of constructing a building comprising: providing a
support structure; providing a plurality of wood based panels, each
with spaced top and bottom surfaces, bounded by edges extending
therebetween, the width of said edges defining the thickness of
said panel; at least one of said edges including a spacer integral
with and projecting from said edge, at least at spaced intervals
along said edge, said spacer projecting from said edge a distance
equal to a predetermined desired spacing, and said spacer having a
thickness laterally of its direction of projection which is
narrower than the width of said edge, said thickness being
sufficient to give said spacer enough strength to resist damage
during handling and installation of said panel, but leaving said
spacer sufficiently weak or sharp that said spacer will collapse or
be pushed into an adjacent panel under the pressure of linear
expansion forces caused by expansion of wood material of which said
panel is made; each of said panels including at least one edge
which is free of such a spacer; securing said wood based panels to
said support structure with the spacer of one panel abutting a
spacer free edge of an adjacent panel, to thereby properly space
said panels from one another.
17- A method of manufacturing wood based panels having spaced top
and bottom surfaces, bounded by edges extending therebetween, the
width of said edges defining the thickness of said panel; at least
one of said edges including a spacer integral with and projecting
from said edge, at least at spaced intervals along said edge, said
spacer projecting from said edge at distance equal to a
predetermined desired spacing for said panels, and said spacer
having a thickness laterally of its direction of projection which
is narrower than the width of said edge, said thickness being
sufficient to give said spacer enough strength to resist damage
during handling and installation of said panel, but leaving said
spacer sufficiently weak or sharp that said spacer will collapse or
be pushed into an adjacent panel under the pressure of linear
expansion forces caused by expansion of the wood materials of which
said panel is made; said method comprising: passing a panel having
top and bottom surfaces and a generally squared off edge between
two spaced opposing cutting blades, one on either side of said
panel adjacent said generally squared off edge, said cutting blade
being positioned to cut away portions of said top and bottom
surfaces of said panel adjacent to said squared off edge, but
leaving said spacer between said cutting blades.
18- A method of manufacturing wood based panels having spaced top
and bottom surfaces bounded by edges extending therebetween, the
width of said edges defining the thickness of said panel; at least
one of said edges including a spacer integral with and projecting
from said edge, at least at spaced intervals along said edge, said
spacer projecting from said edge a distance equal to a
predetermined desired spacing for said panels, and said spacer
having a thickness laterally of its direction of projection which
is narrower than the width of said edge, said thickness being
sufficient to give said spacer enough strength to resist damage
during handling and installation of said panel, but leaving said
spacer sufficiently weak or sharp that said spacer will collapse or
be pushed into an adjacent panel under the pressure of linear
expansion forces caused by expansion of the wood material of which
said panel is made; said method comprising: passing a panel, having
top and bottom surfaces and a generally squared off edge, through a
cutting blade with grooved teeth, said cutting blade being
positioned in the plane of said panel, so as to cut away the spaced
top and bottom portions of the edge of said panel, but leave said
spacer projecting from said edge.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/354,471, entitled SELF GAPPING WOOD BASED
PANELS, filed Feb. 5, 2002.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to wood based panels used in
building, cladding, and flooring.
[0003] All wood-based panel products will undergo dimensional
changes when exposed to elevated moisture conditions. Most panels
are put into service conditions at less than equilibrium moisture
content. Consequently, there would be an uptake in moisture from
the surrounding environment and "growth" in panel dimensions. The
term used to describe this phenomenon is linear expansion, whereby
physical dimensions (length and width) will grow with moisture
uptake.
[0004] There are a number of consequences to linear expansion when
panels 1 are fitted tightly together at joints 3 prior to expansion
(see prior art FIGS. 1-5):
[0005] 1) Panels 1 will buckle as at 4 somewhere along the
unsupported span (FIG. 1);
[0006] 2) Excessive deflection as at 5 may result (FIG. 2), putting
floors 10 out of level; and
[0007] 3) The upper 8 and lower 9 surfaces (top and bottom faces)
of the panel 1 will flare out as at 7 at the panel-to-panel joint 3
in a release of forces (FIG. 3). This flaring 7 of panel edges at
joints 3 is sometimes attributed wholly to edgeswell, where the
uptake of moisture causes "expansion" in the vertical direction,
but is more likely to be a combination of both. Flare-out 7
occurring prior to finishing the structure would necessitate
sanding, adding additional cost to construction. Occurrence of edge
flaring 7 after finishing would cause gypsum board (drywall) 21 to
crack, exterior siding 25 to bulge out, floors 10 to bulge out,
etc.
[0008] 4) Expansion of the floor panels may push walls 13 out of
plumb (FIG. 4);
[0009] 5) Expansion of the wall system 20 might push floors 23,
ceilings 24 and roofs 26 off level (FIG. 5).
[0010] Given the above "expansion" characteristics and consequent
impacts are well known, most manufacturers, their third-party
certification agencies, and governing standards prescribe a minimum
gap at panel joints to allow for linear expansion. The degree of
gap stipulated is dependent on the inherent linear expansion
character of the substrate (i.e., some panels will expand more than
others).
[0011] Most claims and problems of the above nature presented to
panel manufacturers arise from improper installation--the panels
were not gapped as prescribed. Whether due to inexperienced
installers, insufficient gapping from imprecise measurement tools,
or time constraints in building schedules, proper gapping is not
being done on all product installations.
[0012] In 1976, Pettersson et al. filed U.S. Pat. No. 4,095,913
disclosing a tongue and groove joint where the base of the groove
is provided with one or more protuberances to space the tongue from
the base of the groove. The protuberances are made to be deformable
to permit the panels to swell without deforming the structure made
from the panels. However, it is believed that this has never been
commercialized.
[0013] Thus, problems associated with wood based panels being
installed without proper spacing has persisted for many years
without solution.
SUMMARY OF THE INVENTION
[0014] The wood based panel of the present invention includes a
narrow spacer projecting, at least at spaced intervals, from at
least one flat edge of the panel a specified distance. The spacer
width is less than the thickness of the edge of the wood based
panel, yet the width is sufficient to give the spacer enough
strength to resist damage during handling and installation of the
wood based panel. Upon linear expansion the spacer will collapse or
be pushed into an adjacent wood based panel thereby allowing
multiple wood based panels to be placed adjacent to one another and
withstand the forces of linear expansion.
[0015] These and other features, advantages and objects of the
present invention will be further understood and appreciated by
those skilled in the art by reference to the following
specification, claims and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is an exploded view of buckling of prior art panels
that occurs due to linear expansion;
[0017] FIG. 2 is an exploded view of deflection of prior art panels
that occurs due to linear expansion;
[0018] FIG. 3 is an exploded view of flaring of prior art panels
that occurs due to linear expansion;
[0019] FIG. 4 is a sectional view of a prior art floor system that
upon linear expansion has the capability to push walls out of
plumb;
[0020] FIG. 5 is a sectional view of a prior art wall system that
upon linear expansion has the capability to expand the wall thereby
pushing the ceiling/floor/roof out of level;
[0021] FIG. 6 is a broken plan view of wood based panels of the
preferred embodiment of the invention featuring two adjacent square
edges and two adjacent edges having spacer;
[0022] FIG. 7 is a fragmentary perspective view of area VII of FIG.
6;
[0023] FIG. 8 is a fragmentary perspective view of area VIII of
FIG. 6;
[0024] FIG. 9 is a broken plan view of an alternative embodiment
wood based panel having a square edge, a groove edge, a tongue edge
and an edge with spacer;
[0025] FIG. 10 is a fragmentary perspective view of area X of FIG.
9;
[0026] FIG. 11 is a fragmentary perspective view of area XI of FIG.
9;
[0027] FIG. 12 is a partial side view showing a method of
manufacturing using a two saw blade system;
[0028] FIG. 13 is a partial front view depicting a method of
manufacturing using a two saw blade system;
[0029] FIG. 14 is a partial view depicting a method of
manufacturing using a single saw blade with grooved teeth;
[0030] FIG. 15 is a side elevational view of a single saw blade
with grooved teeth;
[0031] FIGS. 16A-C are a series of drawings showing the progress of
the spacer deforming or collapsing in response to linear
expansion;
[0032] FIGS. 17A-C are a series of drawings showing the progress of
the spacer penetrating an adjacent panel in response to linear
expansion.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
[0033] The product of the preferred embodiment of the invention, as
shown in FIG. 6, is a wood based panel 30 comprised of a top
surface 31 and a bottom surface 32 (not shown in FIG. 6). A
relatively thin, narrow spacer 34 projects from edges 33 and 35 of
panel 30, while edges 37 and 39 are squared off, or flush (FIGS. 6
and 7). Spacer 34 is preferably continuous along the length of
edges 33 and 35, but may be interrupted so as to comprise plural
spacers located at spaced intervals along said edges.
[0034] The wood based panel 30 may be constructed of, but is not
limited to, the following; plywood, chip board, oriented strand
board, medium density fiber board, or high density fiber board. The
typical dimensions of the wood based panel 30 are four feet by
eight feet. However, all of the panel dimensions listed below find
use from time to time:
[0035] 3-foot by 6-foot
[0036] 3-foot by 9-foot
[0037] 4-foot by 8-foot
[0038] 4-foot by 9-foot
[0039] 4-foot by 10-foot
[0040] 4-foot by 12-foot
[0041] 8-foot by 8-foot
[0042] 8-foot by 12-foot
[0043] 8-foot by 16-foot
[0044] 8-foot by 24-foot
[0045] 12-foot by 24-foot
[0046] The wood based panel 30 will vary in thickness from about
1/4 to about 13/4 inch. The most typical thicknesses will be about
{fraction (7/16)} to 7/8 inch.
[0047] The extent of the spacer 34 protrusion is a function of the
code gap requirements where the wood based panel 30 is to be used.
The spacer 34 protrusion typically extends from about {fraction
(1/32)} to 1/4 inch form surface of edge 33 of panel 30. Spacer 34
is narrower than the width of panel 30. Spacer 34 should be
sufficiently thick so as to not be broken off during shipping, but
sufficiently narrow, and weak or sharp to collapse, or push into
the adjacent panel when subject to linear expansion forces. The
extent of spacer 34 thickness will typically be from a maximum 2/3
of the panel thickness to a minimum of 0.1 ({fraction (1/10)})
inch. 2/3 of the panel thickness might especially be used for
thinner panels. The optimum thickness for spacer 34 will vary with
panel material used.
[0048] As shown, spacer 34 has a rectangular lateral cross section
(see e.g. FIGS. 7 and 16A). However, it could be rounded, for
example by having a semi-circular or semi-oval cross section. It
could also taper to its leading edge, as with a trapezoidal or
triangular cross section. It could be stepped in cross section.
[0049] In an alternative embodiment of the invention (FIG. 9), wood
based panel 40 has top surface 41 and bottom surface 42.
Additionally, panel 40 has tongue edge 44 and a groove edge 45.
Adjacent panels 40 are interconnected by tongue edge 44 being
inserted into groove edge 45. In contrast, panel end edge 46 is
square or flush, and a relatively narrow, relatively thin spacer
34a projects from opposite end edge 47 (FIGS. 9 and 11).
[0050] A process of manufacture is depicted by referring to FIGS.
12 and 13. Wood based panel 30 is fed between two saw blades 50 at
its edges 33, thereby cutting panel 30 from both top and bottom
surfaces 31 and 32, to leave spacer 34 projecting from edge 33,
between saw blades 50.
[0051] An alternate process of manufacture is depicted in FIGS. 14
and 15. Saw blade 51 is equipped with grooved teeth 52 having
grooves or notches 53 therein, to allow single saw blade 51 to cut
edges 33 to create spacer 34. Blade 51 is oriented in the plane of
panel 31, rather than perpendicular thereto as is the case with
blade 50. Thus, edge 33 is cut back from its exposed face, leaving
spacer 34 where the grooves in teeth 60.
[0052] In use, panels 30 or 40 are placed in abutting relationship,
with spacer 34 abutting the edge 37 or 39 (FIGS. 16a and 17a), or
spacer 34 abutting edge 46. As panel 30 or 40 expands, spacer 34 or
34a is either crushed and collapsed (FIGS. 16b and 16c), or is
pushed into the wood of the adjacent panel 30 or 40, respectively
(FIGS. 17b and 17c). As a result, panel buckling, deflection and
flare-up are avoided, as are walls and ceilings being pushed out of
plumb.
[0053] Panel 30 may be used in numerous situations, including but
not limited to, use as indoor/outdoor floor covering, use as
indoor/outdoor wall covering, or use as ceiling cover.
[0054] The above description is considered that of the preferred
embodiment(s) only. Modifications of the invention will occur to
those skilled in the art and to those who make or use the
invention. Therefore, it is understood that the embodiment(s) shown
in the drawings and described above are merely for illustrative
purposes and not intended to limit the scope of the invention,
which is defined by the followings as interpreted according to the
principles of patent law, including the Doctrine of
Equivalents.
* * * * *