Note: Descriptions are shown in the official language in which they were submitted.
CA 02840714 2013-12-30
WO 2013/009257 PCT/SE2012/050817
MECHANICAL LOCKING SYSTEM FOR FLOOR PANELS
TECHNICAL FIELD
The disclosure generally relates to the field of
mechanical locking systems for floor panels and building
panels. Furthermore, floorboards, locking systems,
installation methods and production methods are shown.
FIELD OF APPLICATION OF THE INVENTION
The present invention is particularly suitable for use in
floating floors, which are formed of floor panels which
are joined mechanically with a locking system integrated
with the floor panel, i.e. mounted at the factory, are
made up of one or more upper layers of veneer, decorative
laminate or decorative plastic material, an intermediate
core of wood-fibre-based material or plastic material and
preferably a lower balancing layer on the rear side of the
core. The following description of known technique,
problems of known systems and objects and features of the
invention will therefore, as a non-restrictive example, be
aimed above all at this field of application and in
particular at laminate flooring formed as rectangular
floor panels with long and shorts edges intended to be
mechanically joined to each other on both long and short
edges. The long and short edges are mainly used to
simplify the description of the invention. The panels may
be square. It should be emphasised that the invention may
be used in any floor panel and it may be combined with all
types of known locking systems, where the floor panels are
intended to be joined using a mechanical locking system
connecting the panels in the horizontal and vertical
directions on at least two adjacent sides. The invention
may thus also be applicable to, for instance, powder based
floors, solid wooden floors, parquet floors with a core of
wood or wood-fibre-based material and a surface of wood or
CA 02840714 2013-12-30
WO 2013/009257 2 PCT/SE2012/050817
wood veneer and the like, floors with a printed and
preferably also varnished surface, floors with a surface
layer of plastic or cork, linoleum, rubber. Even floors
with hard surfaces such as stone, tile and similar
materials are included and floorings with soft wear layer,
for instance needle felt glued to a board. The invention
may also be used for joining building panels which
preferably contain a board material for instance wall
panels, ceilings, furniture components and similar.
BACKGROUND OF THE INVENTION
Laminate flooring usually comprise a core of a 6-12 mm
fibre board, a 0.2-0.8 mm thick upper decorative surface
layer of laminate and a 0.1-0.6 mm thick lower balancing
layer of laminate, plastic, paper or like material. A
laminate surface may comprise melamine-impregnated paper.
The most common core material is fibreboard with high
density and good stability usually called HDF - High
Density Fibreboard. Sometimes also MDF - Medium Density
Fibreboard - is used as core.
Traditional laminate floor panels of this type have been
joined by means of glued tongue-and-groove joints.
In addition to such traditional floors, floor panels have
been developed which do not require the use of glue and
instead are joined mechanically by means of so-called
mechanical locking systems. These systems comprise locking
means, which lock the panels horizontally and vertically.
The mechanical locking systems are usually formed by
machining of the core of the panel. Alternatively, parts
of the locking system may be formed of a separate
material, for instance aluminium or HDF, which is
integrated with the floor panel, i.e. joined with the
floor panel in connection with the manufacture thereof.
CA 02840714 2013-12-30
WO 2013/009257 3 PCT/SE2012/050817
The main advantages of floating floors with mechanical
locking systems are that they are easy to install. They
may also be disassembled and used once more at a different
location. However, there is still a need to improve the
locking strength and to reduce the material costs.
DEFINITION OF SOME TERMS
In the following text, the visible surface of the
installed floor panel is called "front side", while the
opposite side of the floor panel, facing the sub floor,
is called "rear side". The edge between the front and rear
side is called "joint edge". By "horizontal plane" is
meant a plane, which extends parallel to the outer part of
the surface layer. Immediately juxtaposed upper parts of
two adjacent joint edges of two joined floor panels
together define a "vertical plane" perpendicular to the
horizontal plane. By "vertical locking" is meant locking
parallel to the vertical plane in Dl direction. By
"horizontal locking" is meant locking parallel to the
horizontal plane in D2 direction. By "first horizontal
locking" is meant a horizontal locking perpendicular to
the joint edges in D2 direction. By "second horizontal
locking is meant a horizontal locking in the horizontal
direction along the joint which prevents two panels to
slide parallel to each other when they are laying in the
same plane.
By "locking systems" are meant co acting connecting
elements, which connect the floor panels vertically and/or
horizontally. By "mechanical locking system" is meant that
joining may take place without glue. Mechanical locking
systems may also be joined by gluing. By "integrated with"
means formed in one piece with the panel or factory
connected to the panel.
CA 02840714 2013-12-30
WO 2013/009257 4
PCT/SE2012/050817
By "up or upward" means toward the surface and by
"down or downward" means toward the rear side. By
"inwardly" is meant towards the centre of the floorboard
and by "outwardly" means in the opposite direction.
By "carving" is meant a method to form a groove or a
protrusion on an edge of a panel by carving a part of the
edge to its final shape by one or several carving tool
configurations comprising several non-rotating and fixed
chip-removing surfaces located along the feeding
direction.
RELATED ART AND PROBLEMS THEREOF
For mechanical joining of long edges as well as short
edges in the vertical and in the first horizontal
direction perpendicular to the edges several methods may
be used. One of the most used methods is the angle-snap
method. The long edges are installed by angling. The panel
is then displaced in locked position along the long side.
The short edges are locked by horizontal snapping. The
vertical connection is generally a tongue and a groove.
During the horizontal displacement, a strip with a locking
element is bent and when the edges are in contact, the
strip springs back and a locking element enters a locking
groove and locks the panels horizontally. Such a snap
connection is complicated since a hammer and a tapping
block may need to be used to overcome the friction between
the long edges and to bend the strip during the snapping
action.
Similar locking systems may also be produced with a rigid
strip and they are connected with an angling-angling
method where both short and long edges are angled into a
locked position.
81774886
Recently new and very efficient locking systems have been
introduced with a separate flexible or displaceable
integrated tongue on the short edge that allows
installation with only an angling action, generally
5 referred to as "vertical folding". Such a system is
described in WO 2006/043893 (Valinge Innovation AB).
Several versions are used on the market as shown in
figures la-if. la, lb shows a flexible tongue 30 with a
flexible snap tab extending from the edge. Figure lc, id
shows a displaceable tongue with an inner flexible part
that is bendable horizontally in a cross section of the
tongue or along the joint. Such systems are referred to as
vertical snap systems. The locking system may also be
locked with a side push action such that a displaceable
tongue 30 is pushed into a locked position from the long
side edge when adjacent short side edges are folded down
to the sub floor. Figure le shows a fold down system with
a flexible tongue 30 that is made in one piece with the
core. Figure lf shows a long edge locking system in a fold
down system that is connected with angling.
All such locking systems comprise a horizontal locking,
which is accomplished by cooperating hook element in the
form of a strip with a locking element cooperating with a
locking groove.
Several versions of fold down systems are described in
W02006/104436, W02007/015669, W02008/004960, W02010/087752
(Valinge Innovation AB).
Although such systems are very efficient, there is still
room for improvements. It is difficult to insert the
separate tongue 30 during production into a groove 40 over
a strip 6 comprising a locking element 8. The locking
groove 14 reduces the strength and the edges may crack.
CA 2840714 2019-09-23
CA 02840714 2013-12-30
WO 2013/009257 6 PCT/SE2012/050817
The protruding locking strip with the locking element
causes a waste when the edges are machined and such waste
may be considerable in wide tile-shaped floorboards.
It is a major advantage if the strip 6 is more compact and
shorter and if the locking element 8 and the locking
groove 14 are eliminated.
One of the main advantages with the fold down systems is
that there is no requirement that the long edges should be
displaceable. In fact it is an advantage if the long edges
do not slide during angling since a flexible tongue that
is used in some systems presses the short edges apart
during folding.
WO 2006/043893 describes a fold down system with an
essentially horizontal protruding strip that does not have
a locking element. Such fold down system has no horizontal
connection and the short edges may be locked by for
example gluing or nailing to the sub floor. It would be an
advantage if such floorboards could be installed in a
floating manner.
Such a floating installation may be accomplished according
to this disclosure with a locking system that comprises
long edges that are locked in a first horizontal direction
perpendicular to the edge and in a second horizontal
direction along the edge. Long edges that are not
displaced after locking will also keep the short edges
together and prevent separation.
It is known that a separation of short edges of floor
panels may be prevented with increased friction or with
projections and spaces between the long edges that will
counteract mutual displacements along the edge and
consequently prevent the short edges to slide apart.
It is for example known from Wilson US 2,430,200 that
several projections and recesses between a tongue and a
groove in a mechanical locking system may be used to
CA 02840714 2013-12-30
WO 2013/009257 7 PCT/SE2012/050817
prevent displacement along the joint. Such projections and
recesses are difficult to produce, the panels can only be
locked in well-defined positions against adjacent long
edges and they cannot be displaced against each other in
angled position when top edges are in contact.
Terbrack US 4,426,820 describes an impractical locking
system with a perfect fit in a panel made of plastic
material. The perfect fit may prevent displacement along
the joint.
W01994/026999 (Valinge Innovation AB) describes a
mechanical locking system that locks vertically and
horizontally and where a rubber strip or any other sealing
device is applied in the groove or between the flat
projection part of the strip and the adjacent panel edge
as shown principally in figure if. A rubber strip may be
used to increase friction along the joint.
W098/22677 (Golvabia) describes a tongue and groove joint
where several different types of materials are used to
increase friction in order to prevent the edges from
sliding apart perpendicularly to the edge. Example of
materials inserted or applied in the tongue and groove
joint are flock, strip-shaped bands of rubber, plastic,
foamed rubber adhesive coated surfaces in which friction-
increasing material is fixed such as sand, plastic or
rubber particles. Roughened or coarsened surfaces may also
be used.
W003/025307 and W003/089736 (Valinge Innovation AB)
describe that displacement along long edges may be
counteracted or prevented by means of high friction, glue,
mechanical means etc. and that the short edges may be
formed merely with vertical locking means or completely
without locking means. W003/012224 (Valinge Innovation AB)
describes that flexible elastic sealing compounds based on
acrylic plastics, elastomers of synthetic rubber,
CA 02840714 2013-12-30
WO 2013/009257 8 PCT/SE2012/050817
polyurethane-based hot-melt adhesives, etc. may be applied
between the horizontal locking surfaces in order to
compensate moisture movements due to swelling or
shrinking. Such elastically material will increase the
friction and prevent displacement of long edges along the
joint.
Wernersson W02004/083557 discloses floor panels with
mechanical locking means wherein predetermined surfaces of
the edges are provided with splines. There is no
disclosure of the geometry of such mechanical locking
means, how such splines are formed and on which surfaces
they are applied.
WO 2006/123988 (Valinge Innovation AB) describes a panel
with a slide locking system comprises a plurality of small
local protrusions that prevents displacement along the
joint edges when the panels are laying flat on the sub
floor. The protrusions may lock against a flexible rubber
material at the adjacent panel. The short edges are
provided only with a vertical locking comprising a tongue
made in one piece with the core. The panels may be locked
with vertical folding and the slide lock prevents sliding
along the joint after folding. A folding system at the
short edges that only locks vertically and which comprise
a flexible separate tongue is not described.
These known technologies to prevent displacement along the
long edges suffer from several disadvantages. Friction
created by pressure and small hard materials is not
reliable since swelling and shrinking in wood fibre based
panels may change the friction forces, thus the panels may
as time goes slide and the short edges separate from each
other. Friction material that is applied on surfaces that
form active horizontal locking surfaces, such as the
locking surfaces of the locking element and the locking
CA 02840714 2013-12-30
WO 2013/009257 9 PCT/SE2012/050817
groove and upper adjacent joint edges may change the
locking geometry and prevent an easy installation.
SUMMARY
A first overall objective of the present invention is to
provide a locking system for primarily rectangular floor
panels with long and short edges installed in parallel
rows, which allows that the short edges may be locked to
each other with a vertical movement without a horizontal
connection and that such horizontal connection is
accomplished by the locking system on the long edges
comprising a first and second horizontal locking
perpendicular to the edges and along the edges.
The invention is based, in part, on the discovery that
since displacement of the long edges is not needed in a
fold down locking system, there is more freedom to design
the long edges locking system.
The costs and functions should be favourable compared to
known technology. A part of the overall objective is to
improve the function and costs of those parts of the
locking system that locks in the second horizontal
direction along the joint when panels are installed on a
sub floor.
More specifically the object is to provide a second
horizontal locking system on the long edges, hereafter
referred to as 'slide lock" where one or several of the
following advantages are obtained.
The slide lock on the long edges should be activated when
a panel is brought in contact with an already installed
panel and then angled down to the sub floor.
The slide lock function should be reliable over time and
the panels should be possible to lock and unlock in any
position when two adjacent long edges are brought into
contact with each other.
CA 02840714 2013-12-30
WO 2013/009257 1 PCT/SE2012/050817
0
The slide lock should be strong and prevent short edges of
two locked panels from separating when humidity changes or
when people walk on a floor.
The slide lock should be possible to lock with high
precision and without the use of tools.
The locking system and the slide lock should be designed
in such a way that the material and production costs are
low and that flexible materials may be applied in a safe
way without the risk that such separate materials will be
included in the active locking surfaces in an uncontrolled
way.
The invention is based on a general approach that the
locking element and the locking groove at the long edges
should be used to accomplish a horizontal locking
perpendicular to the edge but also along the edge.
The above objects of the invention are achieved wholly or
partly by locking systems, floor panels, and installation
and production methods according to the disclosure herein.
Embodiments of the invention are evident from the
description and drawings.
A first aspect of the invention is a flooring system
comprising a plurality of rectangular floor panels with
short edges and long edges. The panels are adapted to be
installed on a sub floor and connected to each other with
a mechanical locking system for locking the panels
vertically and horizontally. Said locking system
comprising a tongue and a tongue groove for mechanically
locking together adjacent edges vertical to the horizontal
plane, thereby forming a vertical mechanical connection
between the panels. A locking element at a first long edge
and a locking groove at an opposite second long edge form
a first horizontal mechanical connection between adjacent
long edges locking the panels to each other in a direction
parallel to the horizontal plane and at right angles to
CA 02840714 2013-12-30
WO 2013/009257 PCT/SE2012/050817
1 1
said adjacent long edges. The panels are provided with a
short edge locking connection comprising a separate tongue
for locking adjacent short edges in a first vertical
direction, inserted in a fixation groove at a short edge
of a panel. The tongue is preferably at least partly
flexible and/or displaceable. The short edge locking
connection further comprises a locking strip and a locking
cavity for locking adjacent short edges in a second
vertical direction. The short edge locking connection is
configured to lock the adjacent edges in a vertical
direction only. The long edges are provided with a second
horizontal mechanical connection locking the panels to
each other along said adjacent long edges, in a direction
parallel to The horizontal plane and parallel to said
adjacent long edges, when the panel are laying flat on the
sub floor.
Said second horizontal mechanical connection at the long
edges may comprises a locking element and locking groove
with two sets of cooperating locking surfaces, wherein a
first set is located closer to a vertical plane (VP) and
the upper joint edges than a second set.
The two sets of locking surfaces may be inclined such that
a lower part of the locking element is larger than an
upper part.
The vertical extension of the second set of locking
surfaces may be essentially the same or larger than the
vertical extension of the first set of locking surfaces.
The long edge locking system may comprises a third set of
cooperating locking surfaces located at the outer and
lower part of the strip.
There may be a space between the upper part of the locking
element and the locking groove.
CA 02840714 2013-12-30
WO 2013/009257 12 PCT/SE2012/050817
Said second horizontal mechanical connection may comprise
a flexible material which is applied in an essentially
vertical groove.
Said second horizontal mechanical connection may comprise
a flexible material, which is compressed horizontally in
two opposite directions
Said second horizontal mechanical connection may comprise
a flexible material, which is located in an essentially
vertical groove that is complementary with a wedge shaped
locking element.
Said second horizontal mechanical connection may comprise
a friction element located on the upper part of the
locking element that cooperates with a friction groove.
The friction groove may comprise a flexible material.
Said second horizontal mechanical connection may comprise
friction cavities located at the locking element.
Said second horizontal mechanical connection may comprise
compressible material that is applied in the locking
system at surfaces that do not comprise cooperative active
locking surfaces that lock the panels vertically and
horizontally.
The short edge locking connection may be locked with a
vertical snap action where the separate tongue is
displaced in the fixation groove during vertical
displacement.
The short edge locking connection may be locked when the
separate tongue is displaced in the fixation groove along
the short edge.
According to a first preferred embodiment the locking
system at the long edges comprises a locking element and
locking groove with two sets of cooperating locking
surfaces. A first set is located closer to a vertical
plane and the upper joint edges than a second set. The
locking surfaces are preferably inclined such that a lower
CA 02840714 2013-12-30
WO 2013/009257 13 PCT/SE2012/050817
part of the locking element is larger than an upper part.
It is preferred that there is a space between the upper
part of the locking element and the locking groove. Such a
space may be used to give more production tolerances.
Preferably, the vertical extension of the second set of
locking surfaces is essentially the same or larger than
the vertical extension of the first set of locking
surfaces.
According to a second embodiment of the invention the long
edge locking system comprises a flexible material located
in a vertical groove that prevents displacement along the
edges. The flexible material is preferably located between
cooperating surfaces of the locking element and the
locking groove.
According to a third embodiment of the invention the long
edge locking system comprises at least three sets of
cooperative locking surfaces between a locking element
located on a strip and a locking groove. The first and the
second sets are located in the upper part of the locking
element wherein the first set is closer to the upper edges
than the second set. The third set is located on the lower
and outer part of the strip. This geometry is used to
accomplish a strong press fit between the locking element
and the locking groove and the panels will be tightly
secured to each other such that displacement along the
long edges and perpendicular to the short edges will be
prevented.
Such a locking system with a press fit may be made much
stronger than conventional locking systems with hooks at
the short edges.
Said second mechanical connection may comprise a flexible
tongue which is inserted in a fixation groove formed in
the locking groove.
CA 02840714 2013-12-30
WO 2013/009257 14 PCT/SE2012/050817
The above-described locking system at the long edges may
also be used just individually to lock one pair of two
adjacent edges, preferably the long edges, horizontally
perpendicularly to the edges and along the edges. Such a
locking system may be used together with many other types
of locking systems at the other pair of adjacent edges,
preferably the short edges, and may contribute to increase
the horizontal locking strength at the short edges
considerably. This is especially an advantage in large
floors, with a length or width exceeding for example 20 m,
and which are for example installed in commercial areas
where the load on the floor may be considerable.
A second aspect of the invention is two floor panels
provided with a locking system comprising a tongue and a
tongue groove for mechanically locking together adjacent
edges vertical to the horizontal plane, thereby forming a
vertical mechanical connection between the panels. The
locking system further comprises a first horizontal
mechanical connection between adjacent edges for locking
the panels to each other in a direction parallel to the
horizontal plane and at right angles to said adjacent
edges. The first horizontal mechanical connection
comprises a locking element at a first edge and a locking
groove at an opposite second edge. The tongue may be a
separate tongue, preferably at least partly flexible
and/or displaceable, inserted in a fixation groove at an
edge of a panel. The locking system further comprises a
second horizontal mechanical connection locking the panels
to each other along said first and second edge, in a
direction parallel to the horizontal plane and parallel to
said adjacent edges, when the panels are laying flat on a
sub floor.
CA 02840714 2013-12-30
WO 2013/009257 15 PCT/SE2012/050817
The locking element and the locking groove preferably
comprise two sets of cooperating locking surfaces, wherein
a first set is located closer to a vertical plane (VP) and
the upper joint edges than a second set.
At least one of the two sets of cooperating locking
surfaces may comprise a flexible material. The flexible
material may be a flexible tongue inserted in a fixation
groove. The fixation groove may be formed in the locking
groove.
The two sets of locking surfaces may be inclined such that
a lower part of the locking element is larger than an
upper part.
The vertical extension of the second set of locking
surfaces may be essentially the same or larger than the
vertical extension of the first set of locking surfaces.
The locking system may comprise a third set of cooperating
locking surfaces located at the outer and lower part of
the strip.
There may be a space between the upper part of the locking
element and the locking groove.
Said second horizontal mechanical connection may comprise
a flexible material, which is applied in an essentially
vertical groove, said flexible material is preferably
compressed horizontally in two opposite directions. The
flexible material may be complementary with a wedge shaped
locking element.
Said second horizontal mechanical connection may comprises
a friction element located on the upper part of the
locking element that cooperates with a friction groove.
The friction groove may comprise a flexible material.
Said second horizontal mechanical connection may comprise
friction cavities located at the locking element.
81774886
16
Said second horizontal mechanical connection may comprise
compressible material that is applied in the locking system at
surfaces that do not comprise cooperative active locking
surfaces that lock the panels vertically and horizontally.
The edges may be locked with a vertical snap action where the
separate tongue is displaced in the fixation groove during
vertical displacement.
The edges may be locked when the separate tongue is displaced
in the fixation groove along the short edge.
In some embodiments of the invention, there is provided floor
panels provided with a locking system comprising a tongue and a
tongue groove for mechanically locking together adjacent first
and second edges vertically to a horizontal plane, thereby
forming a vertical mechanical connection between the floor
panels, the second edge being opposite to the first edge, the
locking system further comprising a locking element at the
first edge and a locking groove at the second edge forming a
first horizontal mechanical connection between the adjacent
first and second edges for locking the floor panels to each
other in a direction parallel to the horizontal plane and at
right angles to said first and second edges, wherein the first
and second edges are provided with a second horizontal
mechanical connection configured to lock the floor panels to
each other along said first and second edges, in a direction
parallel to the horizontal plane and parallel to said first and
second edges, while the floor panels are locked in the
direction parallel to the horizontal plane and at right angles
to said first and second edges, and wherein the locking element
and the locking groove comprise two sets of cooperating locking
CA 2840714 2019-09-23
,
81774886
16a
surfaces, a first set of the two sets of cooperating locking
surfaces being located closer to a vertical plane and upper
joint edges than a second set of the two sets of cooperating
locking surfaces, and wherein said second horizontal mechanical
connection comprises friction cavities located at the locking
element, the friction cavities extending to an uppermost
surface of the locking element.
BRIEF DESCRIPTION OF THE DRAWINGS
The disclosure will in the following be described in connection
to exemplary embodiments and in greater detail with reference
to the appended exemplary drawings, wherein:
Figs la-f illustrate locking systems according to known
technology.
Figs 2a-d illustrate a short edge locking system according
to preferred embodiments of the invention.
Figs 3a-3f illustrate a long edge locking system according to
preferred embodiments of the invention.
Figs 4a-c illustrate an preferred embodiment of short edge
locking system.
Figs 5a-f illustrate exemplary separate tongues that may be
used in to lock short edges.
Figs 6a-f illustrate preferred embodiments of the invention.
Figs 7a-c illustrate a long edge locking system according to
an embodiment of the invention.
Figs 8a-8b illustrate vertical folding with a conventional
locking system and a locking
CA 2840714 2019-09-23
CA 02840714 2013-12-30
WO 2013/009257 17 PCT/SE2012/050817
system according to an embodiment of the
invention.
Figs 9a-9d illustrate preferred embodiments of the
invention.
DESCRIPTION OF EMBODIMENTS OF THE INVENTION
To facilitate understanding, several locking systems in
the figures are shown schematically. It should be
emphasised that improved or different functions may be
achieved using combinations of the preferred embodiments.
The inventor has tested all known and especially all
commercially used locking systems on the market that are
installed with vertical folding in all type of floor
panels, especially laminate and wood floorings and the
conclusion is that at least all these known locking
systems which have one or more locking elements
cooperating with locking grooves may be adjusted to a
system with a slide lock on the long edges which prevents
displacement along the adjacent edges and with fold down
locking system on short edges that only locks vertically.
The most preferable embodiments are however based on
floorboards with a surface layer of laminate, powder based
paper free surfaces or wood surfaces, a core of HDF or
wood and a locking system on the long edge with a strip
extending beyond the upper edge which allows locking by
angling combined with a tongue and groove joint on the
short edges comprising a separate tongue which preferably
only locks vertically.
All embodiments may be used separately or in combinations.
Angles, dimensions, rounded parts, spaces between
surfaces, etc. are only examples and may be adjusted
within the basic principles of the invention.
Figures 2a -2d show a first preferred embodiment of a
short edge locking system provided with a flexible and
CA 02840714 2013-12-30
WO 2013/009257 18 PCT/SE2012/050817
displaceable tongue 30 in a first edge 1 inserted in a
fixation groove 40 that cooperated with a tongue groove 20
in an adjacent second panel l' and locks the panels in a
first vertical direction according to known technology.
The first panel 1 (strip panel) comprises a protruding
strip 6 that extends outwardly beyond a vertical plane VP.
The second panel 1' comprises a locking cavity 7 that
cooperates with the locking strip 6 and locks the panels
in a second vertical direction. Figure 2e show that the
panels are only locked vertically and that they may be
released or connected horizontally in essentially the same
plane since there is no locking element on the strip and
no hook connections in the locking system that prevents
such horizontal displacement.
Such a locking system may be more cost efficient than
convectional fold down systems since there is no need for
a protruding strip with a locking element. Softer, thinner
and less costly core materials may be used in a locking
system that only is used for vertical locking. The
horizontal locking may be obtained with a slide lock
system at the long edges.
Figure 3a and 3b show a slide lock system according to one
preferred embodiment comprising a tongue 10 and a tongue
groove 9, a locking strip 6, a locking element 8 and a
locking groove 14. A flexible and compressible material 16
such as synthetic or natural rubber or plastic foam is
applied in the upper part of the locking groove 14 as a
layer or in local spots , or on the upper part of the
locking element 8. The upper part of the locking element 8
is formed such that preferably two horizontally opposite
edges press against the compressible material 16a, 16b. In
a wood floor with a lamella core, the locking element and
the locking groove will be formed across the fibre
orientation. The swelling and shrinking in the horizontal
CA 02840714 2013-12-30
WO 2013/009257 19 PCT/SE2012/050817
direction along the wood fibres is extremely small and
will not cause any dimensional changes of the fitting
tolerances between the locking element 8 and the locking
groove 14. The counter pressure will not have any effect
on the locking tolerances and swelling and shrinking of
this part of the locking system will easily be compensated
by the flexibility of the compressible material even in
other wood based materials such as HDF, chipboard or
plywood. It is preferred that the upper part of the
locking element is wedge formed and that it cooperates
with a complementary groove 14. It is preferred that the
inner part of the groove 14 is smaller than the groove
opening. This design may be used to create a friction
connection even without compressible material.
Figures 3c and 3d show a locking system with at least
three sets of cooperative locking surfaces between the
locking element 8 and the locking groove 14. The first
11,12 and the second 21,22 sets are located in the upper
part of the locking element wherein the first set is
closer to the upper edges 4,5 than the second set. The
third set 23,24 is located, preferably below the first and
the second sets, preferably on the lower and outer part of
the strip 6. The locking surfaces are essentially flat but
they may also be curved. The locking surfaces are
preferably inclined. Preferably the angle Al against a
horizontal plane HP of the first set of cooperated
surfaces should be slightly smaller than the angle A3 of
the third set. This geometry may be used to accomplish an
easy locking with angling and a strong press fit between
the locking element 8 and the locking groove 14 and the
panels will be tightly secured to each other such that
displacement along the long edges and perpendicular to the
short edges will be prevented. Preferably all or some of
the cooperating sets of surfaces are made with angles Al,
CA 02840714 2013-12-30
WO 2013/009257 20 PCT/SE2012/050817
A2, A3 that are between 40 - 80 degrees against the
horizontal plane or even more preferably between 45 and 75
degrees.
In wood cores, such as plywood or wood lamella core, it is
preferred the fibre orientation is mainly perpendicular to
the length direction of the edges. Layers in the plywood
core may be adapted such that at least one set of
cooperation surfaces comprises such fibre orientation that
will provide a very high friction and a strong locking
along the joint.
Such a locking system with a press fit with or without
additional preferably flexible friction increasing
materials between the locking element and the locking
groove, may be made much stronger than conventional
locking systems with hooks at the short edges. A
horizontally extending groove 35 may be formed in a wall
or the locking groove 14 in order to increase the
flexibility of one of the locking surfaces 23 in the third
set of locking surfaces. A similar mainly vertical groove
35a may also be formed in the strip 6. The forming may be
made with rotating tools or carving tools.
The locking element and the locking groove may be formed
in a very precise manner if high precision profiling is
used where several tools are positioned at the same tool
station such that the upper edge 4 and the locking element
are formed at the same time in order to eliminate turning
of the panels during machining. The locking groove and the
upper edge 5 may be formed in the same way. . The locking
system may also be formed partly or completely with
carving tools that allow forming of more complex
geometries with undercuts.
CA 02840714 2013-12-30
WO 2013/009257 21 PCT/SE2012/050817
The above described slide lock systems are preferably used
on long edges and in combination with a fold down locking
system on short edges as shown in figures 2a - 2d.
Figures 3e,f show that the flexible material may be
combine with or replaced by with a flexible and preferable
displaceable tongue 30 in one of the edges that is
inserted in a fixation groove 40 and comprises a part,
preferably an outer part, that is in contact with an
adjacent edge and prevents displacement of the edges along
the joint. The flexible tongue 30 is preferably inserted
in a fixation groove 40 that is formed in the locking
groove 14. The outer part of the tongue preferably
comprises small and sharp locking protrusions that
increase the longitudinal friction. The tongue may be
fixed into the fixation groove 40 with friction and/or
glue. One or several tongues 30 may be attached to a one
edge, preferably the long edge of a floor panel.
Figure 3e shows a locking system comprising a tongue 10
and a strip on the same edge 2. This geometry saves
material when the locking system is formed. The adjacent
panel 2' comprises a tongue groove 9 with an upper 9a and
a lower lip 9b that cooperates with the tongue 10 for
vertical locking. The locking groove 14 comprises a
fixation groove 40 that may be inclined in order to
facilitate easy insertion of the flexible tongue 30 into
the fixation groove 40. An outer sliding surface 30a of
the flexible tongue 30 is during angling sliding against a
siding surface 8a on the locking element and the flexible
tongue is displaced inwardly and outwardly in the fixation
groove. All types of tongues, which comprise at least one
part that is flexible, may be used. The outer part of the
flexible tongue may be wedge formed and may in locked
position press with pre tension into the tongue groove
CA 02840714 2013-12-30
WO 2013/009257 22
PCT/SE2012/050817
20a. The upper part of the tongue groove 20a is in this
embodiment inclined upwards and outwardly such that the
panels may be unlocked with an angling action.
The fixation groove may be formed in the outer part of the
strip 6 and it is also possible the replace the flexible
tongue 30 with a sharp nail made of for example plastic or
metal, preferably aluminium.
Figure 3f shows a locking system with a flexible tongue 30
that presses against an upper part 21 of the locking
element 8. Such a locking system may have a flexible
tongue that may is only be displaced with a distance of
less than 0,5 mm. Even 0,1-0,2 mm may be sufficient to
provide a locking.
All described embodiments may be combined. The slide lock
system may also be combined with a conventional one piece
tongue 10 and groove 9 system on the short edges. The
flexible tongue may be designed such that it allows some
displacement especially if a hammer and a tapping block is
used. Two panels may also be connected with the short
edges partly or completely and may thereafter be angled
into a locked position at long edges.
The fixation groove may extend along the whole length or
may be a local groove with a length that may be slightly
longer than the length of the flexible tongue 30.
The slide lock system may also be used independently to
lock panels at one pair of opposite edges and may be
combined with any type of locking system at another pair
of edges, preferably short edges. The slide lock system
may be used to improve the overall locking of the panels
and to increase the locking strengths at another pair of
edges. This may be an advantage in thin panels or soft
core material such as for example PVC where it is
difficult to form large locking element. It is also
CA 02840714 2013-12-30
WO 2013/009257 23 PCT/SE2012/050817
suitable for narrow panels where the length of the locking
element is rather small. Material savings may be obtained
in for example a lamella core wood material where a
separate, stronger and more expensive material usually is
used at the short edges to form the strip and the locking
element.
Figure 4a-4c show that the separate tongue may be attached
to the fold panel 1'.
Figures 5a-5d show that all known tongues may be used in
the short edge locking system. Figure 5a shows a bow
shaped tongue and figure 5b shows a bristle tongue. Such
tongues are bended in length direction during locking.
Figure Sc shows a wedge tongue that is displaced with a
side push action from the long edge such that it is
displaced both along and perpendicular to the edge into
the tongue groove 20. Figure 5d shows as side push rigid
tongue that is only displaced along the edge such that the
protrusions on the tongue overlap the protrusions formed
in the tongue groove 20.
Figure 5e shows a flexible tongue 30 that may be used to
prevent displacement along the edge. The tongue comprises
friction connections 31 that are located in the inner part
of the fixation groove 40 and locking protrusion 32 that
may be in contact with the adjacent edge, preferably an
outer part of the locking element 8. Tongues as shown in
figures 5a and 5b may also be used.
Figure 5f shows a locking system that comprises a flexible
tongue 30 and that is in a locking position whereby one of
the edges 2' is angled to the sub floor. The flexible
tongue 30 is in contact with the outer part of the strip
when the locking element 8 and the locking groove 14
overlaps each other. This specific geometry prevents
separation of the edges during angling.
CA 02840714 2013-12-30
WO 2013/009257 24 PCT/SE2012/050817
Figures 6a-6f show that all known fold down systems may be
adapted to a locking system according to an embodiment of
the invention by removing a part the locking element and
preferably a part of the strip 6. This will provide cost
savings due to less waste and a stronger joint. It is also
possible to form a fold down system in very thin
floorboards for example with a thickness of about 4-6 mm.
Figure 6d shows a side push system with a wedge shaped
tongue and fiaure 6e shows a side push system with a
tongue comprising protrusions. Even one-piece systems with
a machined tongue as shown in figure 6f may be used. A
short strip 6 provides a much easier machining of the
undercut groove 41. This groove 41 may also be formed with
carving
Figure 6d shows that all shown fold down locking systems
may be adjusted such that the edge 6a may be formed
without a protruding strip 6 and the tongue 30 may lock
vertically upwards and downwards.
Figures 7a-7b show preferred embodiments. The long side
locking system comprises a friction element 15, which in
this embodiment is located on the upper part of the
locking element 8, and that cooperates with a friction
groove 17. One advantage is that no compressible material
16 is applied in the active locking surfaces
9a,9b,10a,10b,3,4,11,12 that lock the panels vertically
and horizontally.
Figure 7c shows that the friction may be improved if
friction cavities 18 are formed on the upper part of the
locking element 8 or in the friction element 15. Such
cavities form expansion spaces for the flexible material
16 that may be applied with lower requirements on
production tolerances. The cavities are preferably formed
CA 02840714 2013-12-30
WO 2013/009257 25 PCT/SE2012/050817
with a screw cutter as describe in W02010/087752. Friction
cavities 18' may also be formed on other parts of the
locking system for example the outer part of the strip 6.
Figures 8a and 8b show that known locking systems, as
shown in figure 8a, may easily be converted to a locking
system according to an embodiment of the invention, as
shown in figure 8b, and that the new locking system may be
compatible with the old locking system. Friction cavities
18 are formed in the upper part of the locking element
with a screw cutter, compressible material 16 is
preferably inserted essentially in the groove along the
whole long edge or in parts thereof and the locking
element on the short edges is removed. A flexible tongue
may also be inserted into the long edge as described
above.
The panels are installed such that a long edge 2" of a
new panel in a second row is put at an angle against a
long edge 2 of a first panel installed in a previous row
and displaced until its short edge l' is in contact with a
short edge 1 of a second panel installed in the second
row. The new panel is angled down whereby the flexible
tongue 30 locks the short edges 1,1' vertically. The long
edges comprise a locking system with a friction connection
that prevents displacement of the panels along the long
edges 2, 2', 2".
Figure 9a shows that several friction elements 15, 15' and
friction grooves 17,17' with compressible material 16,16,
may be provided.
Figure 9b shows that the protruding strip 6 at short edges
may be replaced by overlapping upper edges 33, 34 above
the separate tongue 30. It is of course possible to use
both overlapping edges and a locking strip 6 cooperating
with a locking cavity 7.
CA 02840714 2013-12-30
WO 2013/009257 26 PCT/SE2012/050817
Figure 9c shows that flexible and compressible material 16
may be applied on the friction element 15.
The long edge locking along the edge may be accomplished
with a tight fit, with high friction or with all known
methods to prevent displacement along the joint.
Wood floor with a lamella core that generally has a rough
surface may be formed with a locking system with tight fit
and with rather large cooperating locking surfaces. No
flexible materials are needed to obtain sufficient
friction. Such long side locking system is extremely
difficult to displace, especially when the floor boards
are long, for example 1.8 - 2.4 m and the friction force
is generally sufficient to accomplish a locking which
keeps the short edges together during the lifetime of the
floor. Only a few small flexible tongues 30 may be
provided at the long edges in order to give the necessary
extra locking that may be needed in some applications and
in very dry conditions when the wood material shrinks.
The locking strength of the slide lock may be increased
considerably with a locking strip that is slightly bended
and that causes a permanent vertical pressure as shown in
figure 9d. Sufficient friction may be created even in HDF
material that generally is formed with rather smooth
surfaces. A strip 6 that in locked position is bended
backwards will press the locking element 8 into the
locking groove 14 when people walk on the floor or when
furniture is applied on the surface. This will increase
the locking strength of the second horizontal connection
along the long edges. The locking strength may be
increased further if for example a pressing protrusion 23
is formed on the lower part of the strip, preferably under
the locking element. Such pressing protrusion 23 may be
applied as a separate material on essentially the whole
strip 6 or on separate parts along the edge.
CA 02840714 2013-12-30
WO 2013/009257 27 PCT/SE2012/050817
Wedge shaped locking elements 8 that are pressed into a
cooperating locking groove 14 as shown in figure 9d may
create a sufficient friction even without a compressible
friction material. Figure 9d shows embodiment that
comprises a locking element 8 and locking groove with two
sets of cooperating locking surfaces. A first set 11,12 is
located closer to the vertical plane than a second set
21,22. The locking surfaces are preferably Inclined such
that a lower part of the locking element is larger than an
upper part. The locking surfaces may be essentially plane
or curved. It is preferred that there is a space S between
the upper part of the locking element and the locking
groove. Such a space S may be used to give more production
tolerances. The angle Al,A2 of the cooperating surfaces,
or tangent line in case the surfaces are curved, should
preferably be larger than about 45 degrees. Preferably the
vertical extension of the second set 21,22 of locking
surfaces is essentially the same or larger than the
vertical extension of the first set 11,12 of locking
surfaces. The second set should preferably extend
downwards to a level, which is below the first set.
A flexing groove 34, 34' may be formed in the locking
element 8 and/or behind the locking groove 14 in order to
increase the flexibility of the walls of the locking
element 8 or the locking groove 14. Such flexing groove
may also be filled with a flexible material that increases
the flexibility further.
A wedge shaped locking element as described above may be
used to position the upper edges with a small play of for
example of about 0.01 - 0.10 mm. Such a play will allow
the top edges to swell and damages on the upper edges or
squeaking sound will be eliminated. Such locking system is
also very suitable to use in glue down floor installations
CA 02840714 2013-12-30
WO 2013/009257 28 PCT/SE2012/050817
or in combination with bevels between the upper joint
edges.
The above-described embodiment may of course be combined
with friction cavities 18 and flexible material 16 may be
inserted between the locking element and the locking
groove
The locking system may be formed with two or more sets of
locking elements and locking grooves in order to increase
the friction. Small friction grooves 23 parallel with the
joint edge may also increase the friction.
Glue or wax that cures after some time is also possible to
use and may eliminate problems with shrinking and swelling
of a pre tensioned locking system. Wax mixed with
aluminium oxide particles, which are applied in the
locking system, increases the friction considerably.
The long edge locking system may be used with all known
vertical folding systems that lock the short edges
vertically and horizontally.
The separate tongues are generally factory connected into
an edge. Separate lose tongues that are inserted prior to
folding or when two short edges are laying flat on the sub
floor are not excluded.
The long edge locking system may be formed such that it is
displaceable in an angle of 3-5 degrees. This facilitates
installation around doors and similar.
The invention has been described above by way of example
only and the skilled person will appreciate that various
modifications may be made within the scope of the
invention as defined by the appended claims.
