U.S. patent application number 10/800915 was filed with the patent office on 2004-09-23 for panel joint.
Invention is credited to Wernersson, Hakan.
Application Number | 20040182033 10/800915 |
Document ID | / |
Family ID | 20290709 |
Filed Date | 2004-09-23 |
United States Patent
Application |
20040182033 |
Kind Code |
A1 |
Wernersson, Hakan |
September 23, 2004 |
Panel joint
Abstract
A panel joint for positioning and holding panels together via
their respective edges in order to form a surface comprising a
plurality of said panels assembled together. The edges of said
panels are provided with a core and means for mechanically locking
said panels towards one another via interacting locking surfaces.
The edges further comprises friction enhancing means intended for
impeding assembled panels from sliding in a direction along the
edges.
Inventors: |
Wernersson, Hakan; (Lund,
SE) |
Correspondence
Address: |
Stevens Davis, Miller & Mosher, L.L.P.
Suite 850
1615 L Street, N.W.
Washington
DC
20036
US
|
Family ID: |
20290709 |
Appl. No.: |
10/800915 |
Filed: |
March 16, 2004 |
Current U.S.
Class: |
52/578 |
Current CPC
Class: |
E04F 2201/0153 20130101;
E04F 15/02 20130101; E04F 2201/07 20130101; E04F 2201/08 20130101;
E04F 2201/05 20130101; E04F 2201/0115 20130101 |
Class at
Publication: |
052/578 |
International
Class: |
E04C 003/30; E04B
002/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 18, 2003 |
SE |
0300741-6 |
Claims
We claim:
1. A panel joint for positioning and holding panels together via
their respective edges in order to form a surface comprising a
plurality of said panels assembled together wherein the edges of
said panels are provided with a core and means for mechanically
locking said panels towards one another via interacting locking
surfaces, said edges further comprising friction enhancing means
intended for impeding assembled panels from sliding in a direction
along the edges.
2. A panel joint according to claim 1 wherein the force needed to
overcome the static friction along the joint between two assembled
panels is larger than 100 N per meter of joint length, preferably
larger than 1000 N per meter of joint length.
3. A panel joint according to claim 2 wherein predetermined
surfaces of the edge are provided with a rough surface.
4. A panel joint according to claim 3 wherein the core of the
panels is made of a wood based material and that the rough surface
is achieved by wetting the predetermined surfaces of the edge with
a liquid hereby causing fibre of the core to rise.
5. A panel joint according to claim 4 wherein the liquid comprises
a binding agent.
6. A panel joint according to claim 5 wherein the liquid binding
agent is a lacquer.
7. A panel joint according to claim 2 wherein predetermined
surfaces of the edge is coated with a high friction polymer.
8. A panel joint according to claim 7 wherein the high friction
polymer is a natural rubber.
9. A panel joint according to claim 7 wherein the high friction
polymer is a synthetic rubber.
10. A panel joint according to claim 9 wherein the synthetic rubber
is a silicon rubber.
11. A panel joint according to claim 3 wherein the rough surface is
comprised by particles bonded to the predetermined surfaces of the
edges.
12. A panel joint according to claim 11 wherein the particles have
a size in the range 50 .mu.m to 2 mm.
13. A panel joint according to claim 12 wherein the particles have
a higher hardness index than the material of the core.
14. A panel joint according to claim 3 wherein the predetermined
surfaces of the edges is provided with splines.
15. A panel joint according to claim 14 wherein the splines are
arranged at an angle towards the extension of the edge of the
panel.
16. A panel joint according to claim 2 wherein a jagged profile is
arranged between predetermined surfaces of the edges.
Description
[0001] The present invention relates to a panel joint comprising
friction enhancing means intended for impeding assembled panels
from sliding in a direction along the edges.
[0002] Prefabricated floor panels provided with tongue and groove
at the edges are quite common nowadays. These can be installed by
the average handy man as they are very easy to install. Such floors
can, for example, be constituted of solid wood, fibre board or
particle board. These are most often provided with a surface layer
such as lacquer, or some kind of laminate. The panels are most
often installed by being glued via tongue and groove. The most
common types of tongue and groove are however burdened with the
disadvantage to form gaps of varying width between the floor panels
in cases where the installer hasn't been thorough enough. Dirt will
easily collect in such gaps. Moisture will furthermore enter the
gaps which will cause the core to expand in cases where it is made
of wood, fibre board or particle board, which usually is the case.
The expansion will cause the surface layer to rise closest to the
edges of the joint which radically reduces the useful life of the
floor since the surface layer will be exposed to an exceptional
wear. Different types of tensioning devices, forcing the floor
panels together during installation can be used to avoid such gaps.
This operation is however more or less awkward. It is therefore
desirable to achieve a joint which is self-guiding and thereby
automatically finds the correct position. Such a joint would also
be possible to utilise in floors where no glue is to be used.
[0003] Such a joint is known through WO 94/26999 which deals with a
system to join two floor panels. The floor panels are provided with
a locking device at the rear sides. In one embodiment the floor
panels are provided with profiles on the lower side at a first long
side and short side. These profiles, which extends outside the
floor panel itself, is provided with an upwards directed lip which
fits into grooves on the lower side of a corresponding floor panel.
These grooves are arranged on the second short side and long side
of this floor panel. The floor panels are furthermore provided with
a traditional tongue and groove on the edges. The intentions are
that the profiles shall bend downwards and then to snap back into
the groove when assembled. The profiles are integrated with the
floor panels through folding or alternatively, through gluing.
[0004] According to WO 94/26999, the floor panels may be joined by
turning or prizing it into position with the long side edge as a
pivot point. It is then necessary to slide the floor panel
longitudinally so that it snaps into the floor panel previously
installed in the same row. A play is essential in order to achieve
that. This play seems to be marked A in the figures. A tolerance of
.+-.0.2 mm is mentioned in the application. Such a play will
naturally cause undesired gaps between the floor panels. Dirt and
moisture can penetrate into these gaps.
[0005] It is also known through WO 97/47834 to manufacture a joint
where the floor panels are joined by turning or prizing it into
position with the long side edge as a pivot point. According to
this invention a traditional tongue has been provided with heel on
the lower side. The heel has a counterpart in a recess in the
groove of the opposite side of the floor panel. The lower cheek of
the groove will be bent away during the assembly and will then snap
back when the floor panel is in the correct position. The
snap-joining parts, i.e. the tongue and groove, is in opposite to
the invention according to WO 94/26999 above, where they are
constituted by separate parts, seems to be manufactured
monolithically from the core of the floor panel. WO 97/47834 does
also show how the tongue and groove with heels and recesses
according to the invention is tooled by means of cutting machining.
This invention does also have the disadvantage that the best mode
of joining floor panels includes longitudinal sliding for joining
the short sides of the floor panels, which also here will require a
play which will cause unwanted gaps between the floor panels. Dirt
and moisture can penetrate into these gaps.
[0006] It is also known through WO 01/75247 to manufacture a panel
having joining members intended for turning assembly on two
opposite edges while the remaining edges are provided with joining
members which are intended to be joined through vertical motion.
According to the WO 01/75247 invention it has been made possible to
achieve a panel where the fit can be made very tight since no
sliding motion along two joined edges is needed in order to join
the adjacent edge, as is the case with the teachings of WO 97/47834
and WO 94/26999 above. It has showed advantageous to apply the
turning type joint on the long side while the vertical assembly
type joint is applied on the short sides. The strength of the joint
on the short side edges may, in fact, be improved by an improved
friction on the long side edge, which will give the designer more
room for improvements on assembly properties of the short side
joint.
[0007] Yet another floor panel is known from WO 00/63510 which
seems to be intended to be assembled in a manner similar to WO
01/75247 above.
[0008] There is always a great need to improve joint strength on
panel systems as there may be considerable strain especially on
floors made of wood based materials due to the fact that changes in
moisture levels over the year will cause changes in format. It is
also known that the installation of the above identified panels
will cause movement between already installed panels. This movement
is caused by the pushing, knocking and/or sliding action used when
installing the panels. Certain types of panels, for example tiles,
are intended to have both lateral and longitudinal joints aligned
over a larger surface. It is very easy to disturb this alignment
during the installation with known types of panels.
[0009] It is, through the present invention, made possible to
radically improve joint strength whereby an improved panel joint
has been achieved. Accordingly, the invention relates to a panel
joint for positioning and holding panels together via their
respective edges in order to form a surface comprising a plurality
of said panels assembled together. The edges of said panels are
provided with a core and means for mechanically locking said panels
towards one another via interacting locking surfaces. The invention
is characterised in that said edges further comprises friction
enhancing means intended for impeding assembled panels from sliding
in a direction along the edges. This friction enhancing means will
show its greatest effect when arranged on the long sides of
rectangular panels and will radically reduce the stress on the
short side edge joints of these panels. It is according to
different embodiments of the invention also possible to arrange the
friction enhancing means on other sides of panels as well. The
panels may also be square shaped or any other shape that may be
used for panels.
[0010] It is according to different embodiments according to the
invention possible to achieve different friction coefficients it is
however highly desired that the force needed to overcome the static
friction along the joint between two assembled panels is larger
than 100 N per meter of joint length, preferably larger than 1000 N
per meter of joint length.
[0011] According to a first embodiment of a panel joint according
to the invention predetermined surfaces of the edge are provided
with a rough surface. This rough surface may be achieved by wetting
the predetermined surfaces of the edge with a liquid in cases where
the core selected for the manufacturing of the panels is made of a
wood based material. The liquid will here cause the fibre of the
core to rise. In order to increase the stability of the fibre
rising it is advantageous to use a liquid which comprises a binding
agent as for example a lacquer of some kind.
[0012] According to another embodiment of the invention
predetermined surfaces of the edge is coated with a high friction
polymer. This high friction polymer may be a natural rubber or a
synthetic rubber. As examples of suitable rubber materials can be
mentioned; silicon rubber, latex based rubber,
ethylene-propylene-diene-terpolymer rubber,
ethylene-propylene-copolymer rubber, styrene-butadiene rubber and
acrylic co-polymer dispersions.
[0013] According to another embodiment of the invention
predetermined surfaces of the edge are provided with a rough
surface. This rough surface is comprised by particles bonded to the
predetermined surfaces of the edges. The particles suitably have a
size in the range 50 .mu.m to 2 mm. It is also suitable if the
particles have a higher hardness index than the material of the
core. A natural choice of particles for this purpose would be
minerals like sand or the like and it is indeed advantageous if the
particles are irregular and have sharp edges as more rounded
particles could act as a ball bearing. However, if spherical
particles are properly forced into the core material during the
assembly they might work as well. Irregular particles having sharp
edges will in any case require a lower assembly pressure in order
to obtain the same friction effect and is therefore preferred. It
is, besides minerals, also possible to use particles made of
polymeric materials as long as they have a higher hardness index
than the core material. Among such suitable materials can be
mentioned; styrene, acrylic, high density polyethylene,
polypropylene, polycarbonate, phenolic resins and melamine resins.
These materials may also contain fillers like cellulose, talcum or
mica. The sharp edges of these polymeric particles are
advantageously achieved by grinding and therefore scrap material is
a suitable source. Another advantage with polymeric materials is
that they won't dull the edges of tools used for cutting the panels
having the edges herein described to the same extent mineral
particles like sand would.
[0014] According to yet another embodiment of the invention
predetermined surfaces of the edges is provided with splines. These
splines are arranged at an angle towards the extension of the edge
of the panel.
[0015] According to yet another embodiment of the invention a
jagged profile is arranged between predetermined surfaces of the
edges. This profile may be made of metal, thermoplastic material or
of thermosetting material. Like with the particles previously
discussed there may be advantages in selecting materials that don't
blunt tools used during assembly of the panels. It is however
possible to use smaller lengths of jagged edge profiles made of
metal which are put into the joints just before the assembly. This
way the friction enhancing device can be arranged only at critical
locations identified by the installer.
[0016] The panels according to the present invention comprises a
core. The core is most often comprised of particles or fibre of
wood bonded with resin or glue. It is advantageous to coat the
surface closest to the joint in cases where the floor will be
exposed to high levels of moisture since the cellulose based
material is sensitive to moisture. This coating may suitably
incorporate resin, wax or some kind of lacquer. The panels suitably
comprises an upper decorative layer which may be constituted of a
decorative paper impregnated with melamine-formaldehyde resin. One
or more so called overlay sheets of .alpha.-celluloce, impregnated
with melamine-formaldehyde resin may possibly be placed on top of
the decorative layer. The abrasion resistance may be improved by
sprinkling one or more of the sheets with hard particles of for
example .alpha.-aluminium oxide, silicon carbide or silicon oxide.
It is also possible to coat the upper surface with lacquer or some
kind of thermoplastic foil. The lower side may suitably be coated
with lacquer or a layer of paper and resin.
[0017] The invention is not limited by the embodiments shown since
they can be varied within the scope if the invention.
* * * * *