TECHNICAL FIELD
[0001] The invention generally relates to the field of mechanical locking systems for floor
panels and building panels and production methods to insert a tongue into a groove.
FIELD OF APPLICATION OF THE INVENTION
[0002] Embodiments of the present invention are 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 wood or wood veneer, decorative laminate, powder based
surfaces 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. Floor panels with a surface layer of cork, linoleum, rubber or soft wear
layers, for instance needle felt glued to a board, printed and preferably also varnished
surface and floors with hard surfaces such as stone, tile and similar materials are
included. Embodiments of 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.
[0003] The following description of prior-art 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 panels formed as rectangular
floor panels with long and shorts edges intended to be mechanically joined to each
other on both long and short edges.
[0004] The long and short edges are mainly used to simplify the description of embodiments
of the invention. The panels may be square. The invention is preferably used on the
short edges. 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 system formed on the long edges,
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.
BACKGROUND OF THE INVENTION
[0005] 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 comprises 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.
[0006] Laminate floorings 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.
[0007] The main advantages of floating floors with mechanical locking systems are that they
are easy to install. They may also easily be taken up again and used once more at
a different location.
DEFINITION OF SOME TERMS
[0008] 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
plan. By "horizontal locking" is meant locking parallel to the horizontal plane.
By "up" is meant towards the front side, by "down" towards the rear side, by "inwardly"
mainly horizontally towards an inner and centre part of the panel and by "outwardly"
mainly horizontally away from the centre part of the panel.
By "locking systems" are meant co acting connecting elements, which connect the floor
panels vertically and/or horizontally.
RELATED ART AND PROBLEMS THEREOF
[0009] 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 than 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.
[0010] 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.
[0011] 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 referred to as "vertical folding". Such a system
is described in
WO 2006/043893 (Valinge Innovation AB).
[0012] Several versions are used on the market. One of the most used versions is shown in
figures 1a-1d. A flexible tongue 30 is during locking displaced in a horizontally
extending displacement groove 40 and into a tongue groove 20 of an adjacent panel.
The displaceable tongue locks the edges vertically and a strip 6 with a locking element
that cooperates with a locking groove 14 locks the panels horizontally. The locking
is a combination of vertical displacement and turning similar to a scissor action.
The tongue is gradually displaced inwardly during locking from one inner edge to an
outer edge as shown in figure 1d such that the tongue is bent in the length direction.
Such systems are referred to as vertical snap systems and they provide an automatically
locking during the folding action.
[0013] Although such systems are very efficient, there is still a room for improvements.
[0014] High locking force can only be accomplished with high snapping resistance when the
tongue is pressed inwardly and bent in the length direction. This creates separation
forces that tend to push the panels apart during folding. The locking may lose its
strength if the flexibility and pressing force of the tongue decreases over time.
[0015] The flexibility must be considerable and allow that a flexible tongue is displaced
in two directions about 1-2 mm. The material, which is used to produce such tongues,
is rather expensive and glass fibres are generally used to reinforce the flexible
tongue.
[0016] It would be a major advantage if snapping could be eliminated in a system that locks
automatically during folding.
SUMMARY OF THE INVENTION
[0017] An overall objective of embodiment 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 automatically
without a snap action that creates a locking resistance and separation forces of the
short edges during folding.
[0018] A specific objective is to provide a locking system with a separate displaceable
tongue that may be bent in length direction with a lower separation force and that
comprises means that prevent the tongue to slide back into the groove after locking.
[0019] The above objects of embodiment of the invention may be achieved wholly or partly
by locking systems and floor panels according to the disclosure. Embodiments of the
invention are evident from the from the description and drawings.
An aspect of the invention is building panels provided with a locking system for vertical
locking of a first and a second building panel by a vertical displacement of the panels
relative each other. A displaceable tongue is attached into a sidewardly open displacement
groove provided at an edge of the first panel. Said tongue cooperates with a tongue
groove provided at an adjacent edge of the second panel for locking the edges vertically.
A strip protrudes below the displacement groove and outwardly beyond the upper part
of the edge or below the tongue groove and outwardly beyond the upper part of the
adjacent edge. The displaceable tongue comprises a pulling extension at its outer
part configured to cooperate with a pulling protrusion formed at an edge of the adjacent
panel such that the displaceable tongue is pulled out from the displacement groove
and into the tongue groove when the edges of the panels are displaced vertically against
each other.
[0020] Said pulling protrusion may be part of the tongue groove.
[0021] The pulling extension may be inclined in relation to a main horizontal plane of the
panels.
[0022] The pulling protrusion may be inclined in relation to a main horizontal plane of
the panels.
[0023] The displaceable tongue may be provided with a locking hook that prevents the tongue
to slide back into the displacement groove after locking.
[0024] The locking hook may lock against an outer part of the displacement groove.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] 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 1a-d
- illustrate locking systems according to known technology.
- Figs 2a-e
- illustrate a short edge locking system according to the invention.
- Figs 3a-3c
- illustrate a short edge locking system according to preferred embodiments of the invention.
- Figs 4a-c
- illustrate preferred embodiments of short edge locking systems with a separate strip.
- Figs 5a-e
- illustrate a locking system according to an embodiment of the invention with a locking
hook that prevents unlocking.
- Figs 6a-d
- illustrate a tongue according to an embodiment of the invention with increased flexibility
related to bending in length direction.
- Figs 7a-d
- illustrate a method according to an embodiment of the invention to insert a tongue
into a groove.
- Figs 8a-c
- illustrate an embodiment of the invention.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0026] 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 embodiments.
[0027] All embodiments may be used separately or in combinations. Angles, dimensions, rounded
parts, spaces between surfaces etc. are only examples that may be adjusted within
the basic principles of the invention.
[0028] Figures 2a-2e show a first preferred embodiment of a short edge locking system provided
with a flexible and displaceable tongue 30 in an edge of a first panel 1 inserted
in a horizontally extending displacement groove 40. The displaceable tongue 30 has
a pulling extension 31 comprising a tongue pulling surface 32 and tongue locking surface
33. The second adjacent panel 1' has a pulling protrusion 21 with a groove pulling
surface 22 that is also a part of a tongue groove 20 comprising a groove locking surface
23. The pulling surfaces 22, 32 cooperate during the vertical displacement and pull
the displaceable tongue 30 into a tongue groove 20. The pulling extension 31 comprises
a tongue locking surface 33 that locks against a groove locking surface 23 and prevents
vertical displacement of the edges in a first vertical direction. A locking strip
6 and a lower part 39 of the adjacent panel locks the edges in a second vertical direction.
A locking element 8 and a locking groove 14 locks the edges horizontally together
with the upper edges. The vertical connection may be used without the horizontal locking
as shown by figure 2e. Short edges may be locked horizontally by for example friction
between long edges.
[0029] The tongue may be attached into a displacement groove 40 formed on the panel comprising
the strip 6, the strip panel, or on the panel comprising the locking groove, the groove
panel, as shown in figures 3a-3c. The pulling protrusion 21 may extend upwardly or
downwardly and the displacement groove may be inclined against the horizontal plane
HP.
[0030] Figures 4a-4c show that the strip 6 may be formed as a separate material. The pulling
protrusion 21 may be flexible and this may eliminate production tolerances and facilitate
the displacement of the tongue 30 into the tongue groove 20 during folding.
[0031] Figures 5a-5e show that the displaceable tongue 30 may comprise a locking hook 34
that may serve as a friction connection to prevent the tongue 30 from falling out
from the groove 40 but also to prevent the tongue from sliding back after locking.
The locking angle A1 is preferably about 45 degrees or higher. A higher angle facilitates
displacement into the tongue groove 20 but also backward displacement. This may be
prevented by a hook connection 34 that preferably locks against an upper or lower
part of the displacement groove 40. The hook connection is pressed into the groove
by a hammer that inserts the tongue 30 into the groove 40 during production. The hook
34 slides against a bevel formed at the displacement groove 40 as shown in figure
5c. The upper part of the locking element 8 is preferably located vertically below
the tongue locking surface 33 as shown in figure 5d. This gives a stronger locking.
The locking system may have a geometry that allows locking and unlocking with angling.
[0032] Figures 6a-6c show that the displaceable tongue 30 turns and bends in the length
direction during folding when an inner short edge of the tongue, as shown in figure
6b is in locked position and an outer short edge of the tongue 30 is in unlocked position
as shown in figure 6d. The locking function may be improved if cavities 35 are formed
on the displaceable tongue 30. Locking may also be improved if the locking surface
32 at an edge has a lower angle than at an inner part as shown in figures 6b and 6c.
The cavities 35 may be formed at tongue section where the locking hooks 34 are formed.
The displaceable tongue 30 comprises preferably a polymer material and is preferably
formed by injection moulding.
[0033] Figures 7a-7d show that the locking hook 34 may comprise a hook part 34a that is
used to press the hook connection upwards by inserting rails 36 during the insertion
of the tongue 30 into the displacement groove 40.
[0034] Figures 8a-8c show that the locking hook 34 may be used to prevent unlocking in any
locking system where a tongue is displaced in a groove from an inner position to an
outer position. The shown locking system comprises pushing protrusions 38 located
in pushing cavities 37. The pushing protrusions slide against the locking element
8 and push the tongue 30 into a tongue groove 20. The locking element 8 is preferably
located vertically below the cooperating locking surfaces 23,33 of the tongue 30 and
the tongue groove 20.
Embodiments
[0035]
Item 1. Building panels provided with a locking system for vertical locking of a first
(1) and a second (1') building panel by a vertical displacement of said building panels
(1,1') relative each other, a displaceable tongue (30) is attached into a sidewardly
open displacement groove (40) provided at an edge of the first building panel, said
tongue cooperates with a tongue groove (20) provided at an adjacent edge of the second
building panel (1') for locking the edge and the adjacent edge vertically, a strip
(6) protrudes:
below the displacement groove and outwardly beyond the upper part of the edge; or
below the tongue groove and outwardly beyond the upper part of the adjacent edge,
characterised in that
the displaceable tongue (30) comprises a pulling extension (31) at its outer part
configured to cooperate with a pulling protrusion (21) formed at the adjacent edge
such that the displaceable tongue (30) is pulled out from the displacement groove
(40) and into the tongue groove (20) when the edges of said building panels are displaced
vertically against each other.
Item 2. Building panels according to item 1, wherein a part of said pulling protrusion
(21) is a part of the tongue groove (20).
Item 3. Building panels according to item 1 or 2, wherein the pulling extension (31)
and the pulling protrusion (21) are inclined in relation to a main horizontal plane
(HP) of the panels.
Item 4. Building panels according to any one of the items 1 - 3, wherein the displaceable
tongue (30) comprises a locking hook (34) that prevents the tongue to slide back into
the displacement groove (40) after locking.
Item 5. Building panels according to item 4, wherein the locking hook (34) locks against
an outer part of the displacement groove (40).
Item 6. Building panels according to any one of the items 1-5, wherein said building
panels are floor panels.
1. Building panels provided with a locking system for vertical locking of a first (1)
and a second (1') building panel by a vertical displacement of said building panels
(1,1') relative each other, a displaceable tongue (30) being inserted into a sidewardly
open displacement groove (40) provided at an edge of the first building panel,
wherein said displaceable tongue is configured to cooperate with a tongue groove (20)
provided at an adjacent edge of the second building panel (1') for locking the edge
and the adjacent edge vertically,
wherein a strip (6) protrudes:
below the displacement groove and outwardly beyond the upper part of the edge; or
below the tongue groove and outwardly beyond the upper part of the adjacent edge,
wherein the displaceable tongue (30) comprises a pulling extension (31) at its outer
part configured to cooperate with a pulling protrusion (21) formed at the adjacent
edge such that the displaceable tongue (30) is pulled out from the displacement groove
(40) and into the tongue groove (20) when the edges of said building panels are displaced
vertically relative to each other, and
wherein the displaceable tongue (30) comprises a locking hook (34).
2. Building panels according to claim 1, wherein a part of said pulling protrusion (21)
is a part of the tongue groove (20).
3. Building panels according to claim 1 or 2, wherein the pulling extension (31) and
the pulling protrusion (21) are inclined in relation to a main horizontal plane (HP)
of the panels.
4. Building panels according to any of the preceding claims, wherein the locking hook
(34) is configured to prevent the displaceable tongue from sliding back into the displacement
groove (40) after locking.
5. Building panels as according to claim 4, wherein the locking hook (34) is configured
to lock against an outer part of the sidewardly open displacement groove (40).
6. Building panels according to any of the preceding claims, wherein the locking hook
(34) is configured to lock against an upper or lower part of the displacement groove
(40).
7. Building panels according to any of the preceding claims, wherein the locking hook
(34) is configured to serve as a friction connection for preventing the displaceable
tongue (30) from falling out from the displacement groove (40) after locking of the
building panels.
8. Building panels according to any of the preceding claims, wherein the locking hook
(34) is configured to slide against a bevel formed at the displacement groove (40)
.
9. Building panels according to any of the preceding claims, wherein cavities (35) are
formed on the displaceable tongue (30).
10. Building panels according to claim 9, wherein the cavities (35) are formed at a tongue
section where locking hooks (34) of the displaceable tongue (30) are formed.
11. Building panels according to any of the preceding claims, wherein the displaceable
tongue (30) is a separate displaceable tongue.
12. Building panels according to any of the preceding claims, wherein the displaceable
tongue is formed by injection moulding.
13. Building panels according to any of the preceding claims, wherein the locking hook
(34) comprises a hook part (34a) that is configured to press the locking hook upwards
by inserting rails during insertion of the displaceable tongue (30) into the displaceable
groove (40) .
14. Building panels according to any of the preceding claims, wherein an upper part of
the locking element (8) is located vertically below a tongue-locking surface (33)
of the pulling extension (31) in a locked state of the building panels.
15. Building panels according to any of the preceding claims, wherein said building panels
are floor panels.