U.S. patent application number 10/580191 was filed with the patent office on 2007-10-18 for joint for a panel.
This patent application is currently assigned to PERGO (EUROPE) AB. Invention is credited to Nils-Erik Engstrom.
Application Number | 20070240376 10/580191 |
Document ID | / |
Family ID | 30439733 |
Filed Date | 2007-10-18 |
United States Patent
Application |
20070240376 |
Kind Code |
A1 |
Engstrom; Nils-Erik |
October 18, 2007 |
Joint for a Panel
Abstract
A joint for a panel, the joint comprising a first edge and a
second edge. The first edge comprises a groove while the second
edge is provided with a tongue. The second edge further comprises
an upper side groove. A joining profile is provided with a tongue
and an intermediate section, the joining profile being so
configured so as to allowing it to be located in the upper portion
of the joint between two, joined, adjacent panels.
Inventors: |
Engstrom; Nils-Erik;
(Trelleborg, SE) |
Correspondence
Address: |
STEVENS DAVIS MILLER & MOSHER, LLP
1615 L STREET, NW
SUITE 850
WASHINGTON
DC
20036
US
|
Assignee: |
PERGO (EUROPE) AB
Trelleborg
SE
|
Family ID: |
30439733 |
Appl. No.: |
10/580191 |
Filed: |
December 8, 2004 |
PCT Filed: |
December 8, 2004 |
PCT NO: |
PCT/SE04/01827 |
371 Date: |
February 26, 2007 |
Current U.S.
Class: |
52/588.1 |
Current CPC
Class: |
E04F 2201/0115 20130101;
E04F 15/02011 20130101; E04F 2201/05 20130101; E04F 15/02016
20130101 |
Class at
Publication: |
052/588.1 |
International
Class: |
E04C 2/40 20060101
E04C002/40 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 18, 2003 |
SE |
0303420-4 |
Claims
1. A joint for a panel, the joint comprising a first edge and a
second edge whereby the first edge comprises a groove and the
second edge is provided with a tongue wherein the second edge
further comprises an upper side groove, that a joining profile is
provided with a tongue and an intermediate section, the joining
profile being so configured so as to allowing it to be located in
the upper portion of the joint between two, joined, adjacent
panels.
2. A joint for a panel according to claim 1, the joint comprising a
first edge and a second edge whereby the first edge comprises a
groove and the second edge is provided with a tongue wherein the
first edge further comprises an upper side groove and the second
edge comprises an upper side groove, that a joining profile is
provided with a first and second snapping tongue and an
intermediate section, the joining profile being so configured so as
to allowing the first and second snapping tongue to be fitted into
upper side grooves of two, joined, adjacent panels.
3. A joint according to claim 2 wherein the joint further comprises
mating surfaces, that the joining profile and the upper side
grooves are so configured that a play is created in the joint
between the mating surfaces.
4. A joint according to claim 3 wherein the play is in the range
0.05-1 mm.
5. A joint according to claim 1 wherein the tongue and the groove
are configured to limit the movement in a vertical direction
between two adjacent panels.
6. A joint according to claim 2 wherein the joining profile and the
upper side grooves are configured to limit the movement in
horizontal direction between two adjacent panels.
7. A joint according to claim 2 wherein a portion arranged between
the upper side groove and its respective distal edge portion
comprises a recess.
8. A joint according to claim 7 wherein the recess further
comprises one or more supporting protrusions, the supporting
protrusions supporting a lower side of the intermediate section of
the joining profile.
9. A joint according to claim 2 wherein the upper side groove is
provided with a first groove edge surface having an angle .alpha.
of 1-50.degree. towards a vertical plane.
10. A joint according to claim 2 wherein the first groove edge
surface will create a pressure on an outer edge of the joining
profile when two adjacent panels are forced together, the pressure
causing the intermediate section to be urged downwards.
11. A joint according to claim 10 wherein a portion arranged
between the upper side groove and is respective distal edge portion
comprises a recess, the recess being adapted to receive the lower
portion of the intermediate section when being urged downwards.
12. A joint according to claim 2 wherein the upper side groove is
provided with a first groove edge surface and a second groove edge
surface between the first and second groove edge surfaces a
predetermined distance is present, the distance being so configured
that the snapping tongue may be pressed in between the first and
second groove edge surfaces.
13. A joint according to claim 12 wherein the first and second
groove edge surfaces are arranged so that an undercut is present,
that the snapping tongue of the joining profile is adapted to the
undercut so that a snap action locking effect is achieved.
14. A joint according to claim 2 wherein the tongue is provided
with at least one protrusion and that the groove is provided with
recesses arranged to mate with the at least one protrusion, that
the at least one protrusion with matching recess is configured to
allow a predetermined movement in the horizontal plane.
15. A joint according to claim 14 wherein the predetermined
movement is in the range 0.05 mm-1 mm.
16. A joint according to claim 2 wherein the joining profile is
provided with at least one compression zone.
Description
[0001] The present invention relates to a joint for a panel which
are assembled together with separate joining profiles.
[0002] Prefabricated floor boards 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 boards 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 boards
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
boards 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 boards. The floor boards are provided with
a locking device at the rear sides. It is, however, shown in the
figures with accompanying description that the floor boards are
provided with profiles on the lower side at a first long side and
short side. These profiles, which extends outside the floor board
itself, is provided with an upwards directed lip which fits into
grooves on the lower side of a corresponding floor board. These
grooves are arranged on the second short side and long side of this
floor board. The floor boards 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
boards through folding or alternatively, through gluing.
[0004] The invention according to WO 94/26999 is however burdened
with the disadvantage that the profiles are located in a very
exposed position and will easily be damaged during handling.
According to WO 94/26999, the floor boards may be joined without
the lip having to touch the contact surface of the groove at
tolerances as small as .+-.0.2 mm. The profiles are easily deformed
during manufacturing, transport and installation of the relatively
heavy floor boards since the profiles are located in a very exposed
position. Further deformation of the delicate joining profiles is
probable since the intentions are that it should be possible to
disassemble and reinstall the floor boards according to WO
94/26999. Such deformation will obstruct, and in serious cases even
make assembly of the floor boards impossible.
[0005] It seems, from WO 94/26999 to be desired to have a clearance
between the contact surfaces of the lip and the groove. A tolerance
of .+-.0.2 mm is mentioned in the application. The clearance seems
to be marked .DELTA. in the figures. Such a clearance will
naturally cause undesired gaps between the floor boards. Dirt and
moisture can penetrate into these gaps.
[0006] Another disadvantage is that the tongue, located on two of
the edges, must be tooled from the base material which will loss of
the surface layer. Such a surface layer will most often be
constituted of thermosetting laminate and is normally the most
costly part of a laminate floor. A surface layer of thermosetting
laminate will furthermore cause an extensive wear on the tools used
for milling.
[0007] Another disadvantage becomes clear when performing a
life-cycle analysis on the floor boards according to WO 94/26999.
According to one preferred embodiment of WO 94/26999, the joining
profile is constituted of aluminium. Since it constitutes a part
integrated with the floor board it will be practically impossible
to recycle the floor board without a very labour-intensive process.
The inevitable cutting of the floor board will also be very
difficult, utilising common tools, as both aluminium, thermosetting
laminate and core will have to be cut at the same time.
[0008] It is also known through WO 97/47834 to manufacture a joint
where the floor boards are joined so that they are locked together
in the horizontal direction.
[0009] 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 board. The
lower cheek of the groove will be bent away during the assembly and
will then snap back when the floor board 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 board. 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 tongue, and
particularly, the lower cheek of the groove will easily be damaged
during normal handling even though they protrudes less than in the
invention according to WO 94/26999 above.
[0010] Also WO 97/47834 does have the disadvantage that both tongue
and groove will have to be tooled in a way that causes loss of the
costly top surface. This tooling will also cause an extensive wear
on tools used.
[0011] The invention according to WO 97/47834 presumes a certain
amount of resilient properties in the core material. The material
normally used is not very suitable if a resilient property is
desired. MDF (medium density fibre board) or HDF (high density
fibre board) should according to WO 97/47834 be suitable as core
material. The resilient properties of these materials are however,
rather poor, whereby the risk for crack formation, parallel to the
top surface, ought to be great. The invention according to WO
93/13280 deals with a form of clip intended to be used for holding
floor boards together. The floor boards are, besides being provided
with a traditional tongue and groove, with known disadvantages,
also provided with a single groove on the lower side of the floor
board. The floor boards rests on the clip whereby a great number of
clips will have to be used as the floor otherwise will be
resilient. The distance formed between the floor boards and the
surface beneath will furthermore cause acoustic resonance. This
will give the floor a noisy character and a higher sound level.
This is not desired.
[0012] The different types of floor panels described above are all
of the type known as floating floor installations. This means that
the panels are attached, one to the other but not to the subjacent
subfloor. Such a floating floor is allowed to expand and contract
with change in moisture content. Such changes in moisture content
will demand that there is sufficient space between the
circumscribing edge of the floor installation and the surrounding
walls. These space are normally covered by mouldings but in larger
rooms and long corridors it will be necessary to install so called
dilatation profiles to take up the naturally occurring movement in
the floating floor. These dilatation devices are normally bulky and
aren't always a welcome feature in the interior design. It is also
important to take good care of items like water pipes for radiators
coming up through the floor. It has occurred that such pipes have
been caused to leak by expanding floating floor installations.
[0013] Another known problem is when for example a heavy book shelf
is placed in one end of a room and a heavy piano is placed on the
opposite end of the room after a warm wet summer. Once the moisture
content in the panels decreases in the late autumn, the floor will
try to move the piano and book shelf closer to each other. If it
does not succeed in this attempt, and it seldom does, undesired
cracks will appear in the floor.
[0014] The above mentioned problems are solved through the present
invention, whereby a joint for a panel where a predetermined amount
of expansion and contraction in the panel is absorbed in the joint
is achieved. Accordingly the joint comprising a first edge and a
second edge whereby the first edge comprises a groove and the
second edge is provided with a tongue. The second edge further
comprises an upper side groove. A joining profile is provided with
a tongue and an intermediate section. The joining profile is so
configured so as to allowing it to be located in the upper portion
of the joint between two, joined, adjacent panels.
[0015] According to another embodiment of the invention the joint
comprises a first edge and a second edge whereby the first edge
comprises a groove and the second edge is provided with a tongue.
The invention is characterised in that the first edge further
comprises an upper side groove and the second edge also comprises a
upper side groove. A joining profile is provided with a first and
second snapping tongue and an intermediate section. The joining
profile is so configured so as to allowing the first and second
snapping tongue to be fitted into upper side grooves of two,
joined, adjacent panels.
[0016] The joint preferably further comprises mating surfaces. The
joining profile and the upper side grooves are so configured that a
play is created in the joint between the mating surfaces. This play
is designed so that the distance between the mating surfaces is
very small when the moisture level in the panel is at its highest
practical level. The distance will be at its largest when the panel
has low or no moisture content. The play is suitably in the range
0.05-1 mm. A play of up to 1 mm is rather easy to take up in the
joining profile without changing its visual appearance to much.
[0017] The herein described joint may be used on every panel and
every edge thereof in a floor installation. However it is also
possible to use it on portions thereof such as only every other
panel and only on long side edges thereof. The joint can also be
used as a design feature. It is through the present invention
possible to achieve dilatation in a floating floor which is flush
with the upper surface of the floor. This is highly desired.
[0018] The tongue and the groove are configured to limit the
movement in a vertical direction between two adjacent panels, while
the joining profile and the upper side grooves are configured to
limit the movement in horizontal direction between two adjacent
panels.
[0019] A portion arranged between the upper side groove and its
respective distal edge portion preferably comprises a recess. The
recess may according to one embodiment of the invention further
comprises one or more supporting protrusions. These supporting
protrusions is intended for supporting a lower side of the
intermediate section of the joining profile. The upper side groove
is suitably provided with a first groove edge surface having an
angle of 1-50.degree. towards a vertical plane. The first groove
edge surface will then create a pressure on an outer edge of the
joining profile when two adjacent panels are forced together. This
pressure causes the intermediate section to be urged downwards. A
portion arranged between the upper side groove and its respective
distal edge portion then comprises a recess being adapted to
receive the lower portion of the intermediate section when being
urged downwards.
[0020] The upper side groove is suitably provided with a first
groove edge surface and a second groove edge surface between which
first and second groove edge surfaces a predetermined distance is
present. The distance is so configured that the snapping tongue of
the joining profile may be pressed in between the first and second
groove edge surfaces. The first and second groove edge surfaces are
preferably arranged so that an undercut is present. The snapping
tongue of the joining profile is then adapted to the undercut so
that a snap action locking effect is achieved.
[0021] According to one embodiment of the invention the tongue is
provided with at least one protrusion and that the groove is
provided with recesses arranged to mate with the at least one
protrusion. The at least one protrusion with matching recess is
then configured to allow a predetermined movement in the horizontal
plane. This predetermined movement is suitably in the range 0.05
mm-1 mm. The movement in each joint is of course depending on the
maximum and minimum moisture levels in the panel as well as the
distance between the joints according to the invention. However, an
allowed movement of 1 mm/m of panel is more than enough.
[0022] The joining profile is configured to absorb the movement in
adjacent floor panels. This may be achieved in two different ways.
One way is to provide the joining profile with at least one
compression zone. The joining profile or portions of the joining
profile is here suitably made of an elastic material that will
absorb the expansion of the panels. Another way is to allow the
joining profile to bend, either upwards or downwards. It is here
important to make sure that the joint is not allowed to expand more
than the predetermined play to avoid undesired gaps between the
panel and joining profile.
[0023] The joining profiles are suitably shaped as extended
profiles which may be manufactured through extrusion which is a
well known and rational method. The joining profiles are suitably
shaped as extended lengths or rolls which can be cut to the desired
length. The length of the joining profiles considerably exceeds the
length of a floor element, before being cut. An advantage with such
long profiles is that they can be laid over the whole width of the
floor and will thereby reduce the risk for deviations and gaps in
the floor since it bridges the lateral joints of the floor. Such
bridging of the lateral joints can of course be used even if the
joining profiles have the same length as, or is shorter than the
floor elements. Shorter pieces of joining profiles is suitably used
when it comes to the lateral joints of the floor.
[0024] Suitable materials are thermoplastic materials such as
polyolefins, polystyrene, polyvinyl chloride or
acrylnitril-butadiene-styrene-copolymer. These can suitably be
filled with for example wood powder, lime or fibre such as glass
fibre in order to increase the dimension stability. The top,
visible surface of the joining profile may be decorated through any
known means. It is however suitable to make this surface abrasion
resistant enough to match the panels it is to be installed together
with. It is also possible to make the joining profile of metal such
as aluminium or steel. This profile may then be provided with a
bellow-like structure to absorb the movement, have elastic portions
of materials like rubber or being designed to bow downwards or
upwards.
[0025] The invention is described further together with enclosed
figures showing different embodiments of the invention whereby,
[0026] FIG. 1a-c shows in cross-section a joint for a panel
according to a first embodiment of the present invention.
[0027] FIG. 2 shows in cross-section a joint for a panel according
to a third embodiment of the present invention.
[0028] FIG. 3 shows in cross-section a joint for a panel according
to a third embodiment of the present invention.
[0029] FIG. 4 shows in cross-section a joining profile for a panel
according to an embodiment of the present invention.
[0030] FIG. 5 shows in cross-section a joint for a panel according
to a special embodiment of the present invention.
[0031] FIG. 6 shows in cross-section a joint for a panel according
to another special embodiment of the present invention.
[0032] Accordingly, FIG. 1a-c shows in cross-section a joint for a
panel according to a first embodiment of the present invention.
FIG. 1 a shows the joint before assembly wile FIGS. 1b and 1c shows
the same joint after the assembly. The joint is in FIG. 1b in
relaxed state which it will have just after the assembly or when
the panels have equilibrium moisture levels. In FIG. 1c the
moisture levels in the panels are higher than normal which puts the
joint under stress. The joint comprises a first edge 1 and a second
edge 1.sup.I whereby the first edge 1 comprises a groove 11 and the
second edge 1.sup.I is provided with a tongue 21. The first edge 1
further comprises an upper side groove 12. The second edge 1.sup.I
comprises a upper side groove 12. A joining profile 3 is provided
with a first and second snapping tongue 31 and an intermediate
section 33. The joining profile 3 is configured so as to allowing
the first and second snapping tongue 31 to be fitted into upper
side grooves 12 of two, joined, adjacent panels. The joint further
comprises mating surfaces 13 and 23 respectively. The joining
profile 3 and the upper side grooves 12 are so configured that a
play is created in the joint between the mating surfaces 13 and 23
respectively. The tongue 21 and the groove 11 are configured to
limit the movement in a vertical direction between two adjacent
panels while the joining profile 3 and the upper side grooves 12
are configured to limit the movement in horizontal direction
between two adjacent panels.
[0033] A portion arranged between the upper side groove 12 and its
respective distal edge portion comprises a recess. There is a
predetermined distance between a first groove edge surface 16 and a
second groove edge surface 17. The distance is so configured that
the snapping tongue 31 may be pressed in between the first and
second groove edge surfaces 16 and 17 respectively. The first and
second groove edge surfaces 16 and 17 respectively are arranged so
that an undercut is created. The snapping tongue 31 of the joining
profile 3 is adapted to the undercut so that a snap action locking
effect is achieved.
[0034] The joining profile 3 is provided with zones 34 which allows
the profile to be compressed locally.
[0035] The panels most often comprises a core to which an upper
decorative layer has been applied. The core often consists of wood
particle or fibre bonded together by glue or resin. It might be
advantageous to treat the surface closest to the joint in cases
where the floor will be exposed to moisture, since the wood in the
core is sensitive to moisture. This surface treatment may suitably
include resin, wax or some kind of lacquer. It is not necessary to
coat the joint if it is to be glued since the glue itself will
protect the core from moisture penetration. The decorative upper
surface is constituted by a decorative paper impregnated with
melamine-formaldehyde resin. One or more layers of so-called
overlay papers made of .alpha.-cellulose, impregnated with
melamine-formaldehyde resin are possibly placed on top of this. The
abrasion resistance can be improved further by sprinkling one or
more of the layers with hard particles of for example
.alpha.-aluminium oxide, silicon carbide or silicon oxide in
connection to the impregnation. The lower side may suitably be
coated with lacquer or a layer of paper and resin.
[0036] FIG. 2 corresponds mainly to the embodiment shown in FIG. 1.
However, the central portion of the joining profile 3 is supported
by supporting protrusions 15.
[0037] FIGS. 3a-3c shows in cross-section a joint for a panel
according to a third embodiment of the present invention. FIG. 3a
shows the joint before assembly wile FIGS. 3b and 3c shows the same
joint after the assembly. The joint is in FIG. 3b in relaxed state
which it will have just after the assembly or when the panels have
equilibrium moisture levels. In FIG. 3c the moisture levels in the
panels are higher than normal which puts the joint under stress.
The joint comprises a first edge 1 and a second edge 1.sup.I. The
first edge 1 comprises a groove 11 and the second edge 1.sup.I is
provided with a tongue 21. The first edge further comprises an
upper side groove 12 and the second edge 1.sup.I comprises a upper
side groove 12. A joining profile 3 is provided with a first and
second snapping tongue 31 and an intermediate section 33. The
joining profile 3 is configured so as to allowing the first and
second snapping tongue 31 to be fitted into upper side grooves 12
of two, joined, adjacent panels. The joint further comprises mating
surfaces 13 and 23 respectively. The joining profile 3 and the
upper side grooves 12 are so configured that a play is created in
the joint between the mating surfaces 13 and 23 respectively. The
size of this play is of course depending on the moisture content in
the installed panels. The tongue 21 and the groove 11 are
configured to limit the movement in a vertical direction between
two adjacent panels while the joining profile 3 and the upper side
grooves 12 are configured to limit the movement in horizontal
direction between two adjacent panels. The tongue 21 is further
provided with one protrusion 27 on the lower side of the tongue 21.
The groove 11 is provided with a recess 18 arranged to mate with
the protrusion 27. The protrusion 27 with matching recess 17 is
configured to allow a predetermined movement in the horizontal
plane. A portion P arranged between the upper side groove 12 and
its respective distal edge portion E comprises a recess 14. The
recess 14 is adapted to receive the lower portion of the
intermediate section 33 when being urged downwards. The upper side
groove 12 is provided with a first groove edge surface 16 having an
angle .alpha. of 1-50.degree. towards a vertical plane. The first
groove edge surface 16 will create a pressure on an outer edge 36
of the joining profile 3 when two adjacent panels are forced
together, the pressure causing the intermediate section 33 to be
urged downwards.
[0038] The upper side groove is provided with a first groove edge
surface 16 and a second groove edge surface 17 between which first
and second groove edge surfaces 16 and 17 respectively a
predetermined distance D is present. The distance D is so
configured that the snapping tongue 31 may be pressed in between
the first and second groove edge surfaces 16 and 17 respectively.
The first and second groove edge surfaces 16 and 17 respectively
are arranged so that an undercut is present. The snapping tongue 31
of the joining profile 3 is adapted to the undercut so that a snap
action locking effect is achieved. The simplest way to achieve such
an undercut is through broaching or laser cutting.
[0039] FIG. 4 shows an embodiment of a joining profile 3. The
carrying base 3.sup.B of the joining profile 3 is made of extruded
aluminium. The top face of the carrying base 3.sup.B is provided
with grooves 3.sup.G for elasticity. The top face 3.sup.B is then
coated with a decorative thermosetting laminate 3.sup.S with hard
particles in the surface for increased abrasion resistance.
[0040] FIG. 5 shows in cross-section a joint for a panel according
to a special embodiment of the present invention. FIG. 5 shows the
joint after the assembly. The joint is in FIG. 5 in relaxed state
which it will have just after the assembly or when the panels have
equilibrium moisture levels. The joint comprises a first edge 1 and
a second edge 1.sup.I whereby the first edge 1 comprises a groove
11 and the second edge 1.sup.I is provided with a tongue 21. The
tongue 21 is further provided with one protrusion 27 on the lower
side of the tongue 21. The groove 11 is provided with a recess 18
arranged to mate with the protrusion 27. The tongue 21 and the
groove 11 are configured to limit the movement in a vertical
direction between two adjacent panels while the protrusion 27 with
matching recess 17 is configured to allow a predetermined movement
in the horizontal plane. The second edge 1.sup.I comprises a upper
side groove 12. A joining profile 3 is provided with a tongue 31
and an intermediate section 33. The joining profile 3 is configured
so as to allowing the tongue 31 to be fitted into upper side groove
12 during the manufacturing or before joining the panels. The
joining profile 3 and the upper side grooves 12 are so configured
that a play is created in the.
[0041] The joining profile is made of an elastic material, suitably
a thermo-elastic or a natural rubber.
[0042] FIG. 6 shows in cross-section a joint for a panel according
to another embodiment of the present invention. FIG. 6 shows the
joint after the assembly. The joint comprises a first edge 1 and a
second edge 1.sup.I whereby the first edge 1 comprises an upper
side groove 12. Also the second edge 1.sup.I comprises a upper side
groove 12. The first and second edges 1 and 1.sup.I respectively
are also provided with a lower side groove 12.sup.L. In certain
embodiments of the invention the lower side groove 12.sup.L is only
present on the second edge 1.sup.I. A joining profile 3 is provided
with a first and second snapping tongue 31.sup.I and 31.sup.II
respectively, and an intermediate section 33. The first snapping
tongue 31.sup.I is further provided with a lower snapping tongue
31.sup.L, allowing the joining profile 3 to be assembled on the
first or second edge 1 and 1.sup.I respectively, prior to
assembling the panels. The joining profile 3 is configured so as to
allowing the first and lower snapping tongue 31.sup.I and 31.sup.L
respectively, to be fitted into the edge of a first panel after
which panel with fitted joining profile is joined with another
panel via the second, remaining, snapping tongue 31.sup.II of the
joining profile 3. It is advantageous to pre-assemble the joining
profile 3 with the panel already in factory. The joining profile 3
is advantageously manufactured through means of extrusion moulding.
It is suitable to make the material used for the snapping tongues
31.sup.I, 31.sup.II and 31.sup.L of a comparatively stiff plastic
material while the material in the intermediate section 33 is made
of a comparatively soft and resilient material. The different
material composition of the joining profile 3 is illustrated by the
use of different cross-section hatching in FIG. 6. Among materials
suitable for the manufacturing of a joining profile can be
mentioned, polyolefins such as polyethylene and polypropylene which
may be modified with ethyl-vinyl-acetate (EVA) to achieve desired
resilient and elastic properties.
[0043] The invention is not limited by the embodiments shown since
they can be varied in different ways within the scope of the
invention. The joining profile 3 may for example be made of a
multiple of different materials such as a thermosetting or
thermoplastic material, with or without filler materials and fibre
for reinforcement. It is also possible to make the joining profile
3 of metal such as aluminium and steel. It is also possible to use
combinations of materials such as aluminium and thermoplastic or
thermo-elastic material. Finally the upper face of the joining
profile may be decorated with a decorative material such as a
thermosetting laminate, a thermoplastic foil, a solid wood, a metal
foil, a lacquer, a transfer print, a natural rubber or a
thermo-elastic material.
* * * * *