Note: Descriptions are shown in the official language in which they were submitted.
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FLOORBOARDS, FLOORING SYSTEMS AND METHODS FOR
MANUFACTURING AND INSTALLATION THEREOF
Field of the Invention
The invention relates generally to the field of
floorboards. The invention concerns floorboards which
can be joined mechanically in different patterns so as
to resemble traditional parquet flooring consisting of
blocks. The invention also relates to methods for laying
and manufacturing floorboards. The invention is specifi-
cally suited for use in floating flooring which consists
of floorboards having a surface of laminate and being
joined by means of mechanical locking systems integrated
with the floorboard, for instance of the kinds that are
not wholly made of the core of the floorboard. However,
the invention is also applicable to other similar floor-
boards which, for instance, have a surface layer of wood
or.plastic and which are joined in a floating manner by
means of optional mechanical joint systems.
Field of Application of the Invention
The present invention is particularly suited for use
in floating laminate flooring with mechanical joint sys-
tems. These types of flooring usually consist of a sur-
face layer of laminate, a core and a balancing layer and
are shaped as rectangular floorboards intended to be
joined mechanically, i.e. without glue along both long
sides and short sides vertically and horizontally.
The following description of prior-art technique,
problems of known systems and objects and features of
the invention will therefore, as non-limiting examples,
be aimed at above all this field of application. However,
it should be emphasized that the invention may be used in
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optional floorboards which are intended to be joined in
different patterns by means of a mechanical joint system.
The invention may thus also be applicable to homogeneous
wooden flooring and wooden flooring consisting of several
layers, flooring with a core of wood fibers or plastic
and with a surface which is printed or which consists of
plastic, cork, needle felt and like material.
Background Art
Parquet flooring was originally laid by laying
blocks of suitable shape and size in different patterns
and joining them by gluing to a sub-floor. Then the floor
is usually ground to obtain an even floor surface and
finished using, for instance, varnish or oil. Traditional
parquet blocks according to this technology have no lock-
ing means at all, since they are fixed by gluing to the
sub-floor. The main drawback of such a flooring is that
it is very difficult to install. The main advantage is
that the absence of locking means allows laying in
complicated and attractive patterns.
According to another known method the blocks are
formed with a groove along all edges round the block.
When the blocks are then laid by gluing to the sub-floor,
tongues are inserted into the grooves in the positions
where required. This thus results in a floor where the
blocks are locked vertically relative to each other by
the tongue engaging in grooves of two adjoining blocks.
The surface becomes smooth and the blocks can thus be
delivered with a completed varnished surface. The hori-
zontal joint is obtained by nailing or gluing to the sub-
floor.
Traditional parquet blocks are rectangular and
usually have a size of about 7*40 cm. The advantage of
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the above flooring is that the blocks can be laid. in
attractive patterns, for instance, in parallel rows with
the short sides offset relative to each other, in diamond
pattern or in herringbone pattern where the blocks are
joined long side to short side. The drawback of such
flooring is above all that laying and manufacture are
complicated and expensive. Such flooring cannot move
relative to the sub-floor. As the blocks shrink and swell
owing to changes in relative humidity (RH), undesirable
joint gaps arise between the blocks.
In order to solve these problems, first the floating
wooden flooring was developed. Such flooring consists of
considerably larger floorboards with a width of for
instance 20 cm and a length of 120-240 cm. The surface
consists as a rule of parquet blocks which are joined in
parallel rows. Such floorboards facilitate installation
since a plurality of blocks can be joined simultaneously.
The main drawback is that it is not possible to provide
advanced patterns. Later, floating laminate flooring was
developed, which basically was a copy of the floating
wooden flooring except that the decorative surface layer
consisted of a printed and impregnated sheet of paper
that was laminated to a wood fiber core. Such a
floorboard was less expensive than a wooden floor and had
a more wear and impact resistant surface. Floating floor-
boards of this type are joined only at their joint edges,
i.e. without gluing, on an existing sub-floor which does
not have to be quite smooth or plane. Any irregularities
are eliminated by means of underlay material in the form
of, for instance, hardboard, cork or foam. They may thus
move freely on the sub-floor. In case of changes in rela-
tive humidity, the entire floor swells and shrinks. The
advantage of floating flooring with a surface of e.g.
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wood or laminate is that the joints between the floor-
boards are tight and the change in size takes place
hidden under the baseboards. Such floorboards have a sig-
nificantly larger surface than the blocks, which enables
quicker laying and rational production. Traditional such
floating laminate and wooden floorings are usually joined
by means of glued tongue-and-groove joints (i.e. joints
with a tongue on one floorboard and a tongue groove on
the adjoining floorboard) on long side and short side. In
laying, the boards are brought together horizontally, a
projecting tongue along the joint edge of one floorboard
being inserted into a tongue groove along the joint edge
of an adjoining board. The same method is used on long
side and short side, and the boards are as a rule laid in
parallel rows long side against long side and short side
against short side.
In addition to such traditional floating flooring
which is joined by means of glued tongue-and-groove
joints, floorboards have been developed in recent years,
which do not require the use of glue but are instead
joined mechanically by means of mechanical locking sys-
tems. These systems contain locking means which lock the
boards horizontally and vertically. The mechanical lock-
ing systems can be formed in one piece with the
floorboard, e.g. by machining a part of the core of the
floorboard, by machining a part the core of the board.
Alternatively, parts of the locking system can be made of
a separate material which is integrated with the
floorboard, i.e. joined with the floorboard even in the
manufacture thereof at the factory. The floorboards are
joined, i.e. interconnected or locked together, by diffe-
rent combinations of angling, snapping-in and insertion
along the joint edge in the locked position. The floor-
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boards are joined successively, i.e. the preceding floor-
board is connected to another floorboard on one long side
and one short side when a new floorboard is joined with
the preceding one.
5 The main advantages of floating floorings with
mechanical locking systems are that they can be laid
still more easily and quickly and with great accuracy
by different combinations of inward angling and/or
snapping in. In contrast to glued floors, they can also
easily be taken up again and reused in another place.
Definition of Some Terms
In the following text, the visible surface of the
installed floorboard is called "front side", while the
opposite side of the floorboard, facing the sub-floor,
is called "rear side". The sheet-shaped starting material
that is used in manufacture is called "core". When the
core is coated with a surface layer closest to the front
side and generally also a balancing layer closest to
the rear side, it forms a semimanufacture which is called
"floor panel" or "floor element" in the case where the
semimanufacture, in a subsequent operation, is divided
into a plurality of floor panels mentioned above. When
the floor panels are machined along their edges so as to
obtain their final shape with the joint system, they are
called "floorboards". By "surface layer" are meant all
layers applied to the core closest to the front side and
covering typically the entire front side of the floor-
board. By "decorative surface layer" is meant a layer
which is mainly intended to give the floor its decorative
appearance. "Wear layer" relates to a layer which is
mainly adapted to improve the durability of the front
side, By "laminate flooring" is meant a floorboard with a
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surface layer of a thermosetting laminate comprising one
or more paper sheets impregnated with a thermosetting
resin. The wear layer of the laminate flooring consists
as a rule of a transparent sheet of paper with aluminum
oxide added, impregnated with melamine resin. The
decorative layer consists of a melamine impregnated
decorative sheet of paper.
The outer parts of the floorboard at the edge of the
floorboard between the front side and the rear side are
called "joint edge". As a rule, the joint edge has seve-
ral "joint surfaces" which can be vertical, horizontal,
angled, rounded, beveled etc. These joint surfaces exist
on different materials, for instance laminate, fiber-
board, wood, plastic, metal (especially aluminum) or
sealing material. By "joint" or "locking system" are
meant co-acting connecting means which connect the floor-
boards vertically and/or horizontally. By "mechanical
locking system" is meant that joining can take place
without glue horizontally parallel to the surface and
vertically perpendicular to the surface. Mechanical
locking systems can in many cases also be joined by means
of glue. By "integrated" means that the locking system
could be made in one piece with the floorboard or of a
separate material which is factory-connected to the
floorboard. By "floating floor" is meant flooring with
floorboards which are only joined with their respective
joint edges and thus not glued to the sub-floor. In case
of movement due to moisture, the joint remains tight.
Movement due to moisture takes place in the outer areas
of the floor along the walls hidden under the baseboards.
By "parquet block" is meant a rectangular floorboard hav-
ing the shape of a traditional parquet block or strip.
The most common format is about 40*7 cm. However, the
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parquet block may also have a length of 15-80 cm and a
width of 4-10 cm. By "floor unit" are meant several
floorboards which are joined and which constitute part of
the flooring. By "length" and "width" of the floorboard
are generally meant the length and width of the front
side.
Prior-Art Techniaue and Problems thereof
The size of a floorboard is to a considerable extent
related to the material of the floorboard, the machining
of the edges, the type of locking system and the
installation of the floorboards.
It is generally an advantage to produce a floorboard
of solid wood in a small size since defects such as
cracks, knots etc can be cut of and the wood raw material
could be used more efficiently.
It is however an advantage to produce most other
types of floorboards, especially laminate floorings, in
large sizes since this gives a better utilization of the
raw material and lower production costs. This is
especially favorable when the floorboards are produced
from large floor panels with an artificial surface, which
is for instance printed. In such a case, it is of course
an advantage to reduce the saw cuts as much as possible.
The machining of the joint edges to form floorboards
is an expensive operation in all types of floor
materials. It is known that a floor consisting of large-
sized panels with few joints have a considerable cost
advantage against a floor which consists of many small-
sized panels. It is also known that that small sizes of
floor panels would cause disadvantages in a floor,
especially in a floor where the floorboards are
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rectangular and narrow, thus having a large amount of
joints at the long sides of the narrow panels.
It is known that small-sized floorboards with
mechanical locking systems would he more expensive to
produce than similar panels with traditional tongue and
groove systems. It is also known that mechanical locking
systems, which enable a high quality locking with
angling, due to the larger amount of material required
for forming the locking system, are generally more costly
and complicated to machine than the more compact snap
systems. Mechanical locking systems of any kind on the
long sides of a rectangular panel are in general more
costly to produce than any type of mechanical locking
system on the short sides.
In general a floor, which consists of large panels,
could be installed faster than a floor, which consists of
small floor panels.
W001/66877 discloses a system for providing a
patterned flooring consisting of laminate floorboards.
Two embodiments axe disclosed: a first one (Fig. 4a, 4b)
where an integrated locking system is used, and a second
one (Fig. 5 and Fig. 6,) where a separate joining profile
is used. The floorboards are locked by a vertical non-
releasable snapping only. In the first, integrated
embodiment, two different types of floorboards, termed
"male" and "female", are required. Installation with
vertical snapping is complicated and there is a consid-
erable risk that the edges or part of the locking system
is damaged during locking or unlocking. Furthermore,
WO01/66877 is aimed at floorboards having a size of 1200
mm by 200 mm.
WO00/20705 discloses a system for locking together
laminate floorboards by means of a separate joining
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profile, which is connected to the floorboards when they
are being installed. The joining profile is adapted for
locking together the floorboards by non-releasable
snapping only. A specific objective of WO00/20705 is to
decrease the amount of material waste in connection with
production of the floorboards, and especially in connec-
tion with the forming of the mechanical locking system.
DE 197 18 319 C2 discloses a solid wood parquet
strip having a locking system along its long and short
edges, for locking together the parquet strip with other
parquet strips in connection with laying. Gluing the par-
quet strips is, however necessary, and the purpose of the
mechanical locking is to keep the floorboards together
while the glue cures. The mechanical locking is only pro-
vided in a horizontal direction. The parquet strips are
stated to have a length of 250-1000 mm and a width of 45-
80 mm.
To facilitate the understanding and the description
of the present invention as well as the knowledge of the
problems behind the invention, a more detailed descrip-
tion of these specific size-related features and prior-
art technique now follows with reference to Figs 1-3 in
the accompanying drawings.
The major part of all floating laminate floors
(Fig. 1a) consists of rectangular floorboards 1' with
a length 4a of about 120 cm and a width 5a of about
20 cm. By means of modern printing technology, laminate
flooring can be manufactured which in terms of appearance
are very true copies of various natural materials such as
wood and stone. The most common pattern is an imitation
of parquet flooring consisting of blocks 40. These blocks
usually have a width of about 7 cm and a length of
20-40 cm. As a rule, the floorboard contains three rows
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of parallel blocks whose short sides are offset relative
to each other. This means that at least one block 41 at
the short side 5a, 5b of the floorboard will be shorter
than the other two blocks. When the floorboards are join-
5 ed (Fig. 1b), the result will be an unnatural appearance
compared with a real traditional parquet floor consisting
of blocks of equal length, with their short sides offset.
The same applies to floating wooden flooring.
A further problem which causes an unnatural appear
10 ante is related to the manufacturing technology. This is
shown in Fig. 2. Laminate flooring is manufactured by a
printed decorative sheet of paper being impregnated with
melamine resin and laminated to a wood fiber core so that
a floor element 2 is formed. The floor element 2 is then
sawn into, for instance, some ten floor panels 3 which
are machined along their edges to floorboards 1. The
machining along the edges is carried out by the long
sides 4a, 4b of the panels first being machined in a
machine 101, after which they are moved to another
machine 105 which machines the short sides. In connec-
tion with impregnating, the decorative paper swells in an
uncontrolled manner. The swelling and the manufacturing
tolerances arising in connection with laminating, sawing
and machining along the edges result in the position of
the blocks in different floorboards deviating from the
desired position. When two floorboards are joined with
their short sides against each other, the blocks 41a,
41b may be laterally offset and their length may vary
significantly (Fig. lc). All these circumstances cause
great manufacturing problems in connection with manufac-
ture of laminate flooring with a 3-block parquet pattern.
In order to solve these problems, a number of expen-
sive methods have been used to control the manufacturing
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process when making laminate flooring. The most common
method is that the production is controlled using advanc-
ed cameras which automatically measure and position the
semi-manufactures during the manufacturing process.
Different patterns are also made by special displacements
of the blocks so that the position defects are concealed
as much as possible. In wooden flooring, blocks of
varying length and parallel displacement are used to
conceal the cut-off blocks on the short side. All prior-
art methods give an unsatisfactory result. Floating
flooring could reach a larger market if natural parquet
patterns could be provided in combination with rational
production and laying.
Figs 3a-3d show examples of mechanical locking
systems which are used in floating flooring. All these
systems cause waste W. This waste arises in connection
with sawing (SB) and in connection with machining of the
mechanical connecting means. To minimize this waste W,
the manufacturer strives to make the floorboards as large
as possible and with as few joints as possible. Therefore
the floorboards should be wide and long. Narrow floor
boards contain many joints per square meter of floor
surface. Such narrow laminate floorboards with a width
and length corresponding to a traditional parquet block
are not known. The narrowest laminate floorboards have a
width exceeding 15 cm and a length exceeding 100 cm. Fig.
3e shows connection by inward angling and Fig. 3f shows
connection by snapping-in of two adjacent sides 1, 1' of
two floorboards.
Summary of the Invention
An object of the present invention is~to provide
floorboards which can be joined mechanically to a float-
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ing flooring with a natural parquet pattern which in
terms of appearance corresponds to traditional parquet
blocks. A further object is to provide suitable joint
systems, laying methods and laying patterns for these
floorboards.
The invention is based on a first understanding that
modern production technology and mechanical joint systems
in combination with special laying methods make it pos-
sible to join very small floorboards quickly and with
extremely great accuracy. A surprising result is that
flooring which consists of small floorboards can be
installed almost as quickly and with the same quality
as traditional flooring consisting of considerably larger
floorboards. It is also possible to provide an installa-
tion which is quicker and gives a better result than
large floorboards with mechanical joint systems. The rea-
son is that we have discovered that small floorboards are
easier to handle, the frictional surfaces along the long
sides of the joint portions will be smaller, which faci-
litates displacement, and finally snapping-in of the
short side can take place with lower force since the
parts that are bent in connection with snapping-in are
smaller and afford less resistance. An additional
advantage is that the short side of narrow floorboards
could be produced with a locking system, which only locks
horizontally and which do not require a vertical snap.
Such a locking system could be accomplished by for
example removing the tongue 22 on the short side of a
rectangular floorboard with a locking system similar to
Fig. 3b. The narrow short sides (5a, 5b) of two locked
floorboards will nevertheless be held in the desired
vertical position by the locked long sides (4a, 4b), in a
floor where the floorboards are installed in parallel
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rows with offset short sides (see Figs 9f, 4a-4d). Such a
floor could be installed very easy, since the installa-
tion only requires an angling of the long sides. Floor-
boards could be produced with an angling locking system
on long side and without any locking system on the short
side at all. The short sides could be kept together by
the friction of the long sides or by gluing and/or
nailing down the floorboards to the sub-floor. Such
narrow short sides could be installed faster but with the
same high quality as wide short sides. Conversely, wider
short sides, without any vertical locking system, would
increase the risk of the short sides becoming warped,
thus creating an uneven floor.
The invention is based on a second and very sur-
prising understanding that the production cost for small
floorboards with mechanical joint systems need not neces-
sarily be higher than for large floorboards. Small floor-
boards certainly contain essentially more joints per
square meter of floor than large floorboards and the
machining COSt as well as the amount of waste are great
when using the prior-art mechanical joint systems. How-
ever, these problems can largely be avoided if the floor-
boards are produced and if joint systems are formed
according to the invention. Small floorboards imply that
a larger amount of the raw material of wood can be uti-
lized since it is easier to make small blocks without
knots and defects than it is in the manufacture of large
boards. The format of the floorboard and its location in
the floor can also be used to create in a cost-efficient
manner the decorative appearance of a floor which is made
by sawing a floor element, for instance a laminate floor.
By sawing, for example, a floor element in the format
2.1 * 2.6 m with a printed veneer pattern, some hundred
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floorboards can be manufactured. Such small floorboards,
which can have the shape of a parquet block, can be join-
ed in different patterns with different laying direc-
tions. Then a parquet pattern of blocks can be created,
which cannot be manufactured using today's technique. The
swelling problems of the decorative paper are eliminated,
and accurate positioning and pattern alignment in connec-
tion with sawing are not necessary. This reduces the pro-
duction cost. If the floorboards are narrow, any angular
errors between long side and short side will be less
visible in a narrow floorboard than in a wide.
The invention is based on a third understanding that
it is possible and even advantageous in floating flooring
to use small floorboards with a format corresponding to,
for instance, traditional blocks. Such a floating floor-
ing will consist of essentially more joints than a tradi-
tional flooring consisting of large boards. The great
amount of joints per unit area reduces the movement of
the floor along the walls since each joint has a certain
degree of flexibility. A laminate flooring moves for
instance about 1 mm per meter as relative humidity varies
over the year. If the floorboards have, for instance, a
width of 66 mm, each meter will contain 15 joints. A
shrinkage will then result in a maximum joint gap between
two adjacent top edges of two floorboards of 0.06 mm,
provided that the floor owing to load is prevented from
moving. Such a joint gap is invisible. This joint gap
should be adapted to the floor type. In laminate floors a
joint gap of 0.01-0.1 or somewhat larger could be
sufficient. In a solid wood floor made of oak, a joint
gap could be in the order of 0.1-0.2 mm. It may be an
advantage if such a joint gap could be combined with a
bevel at the upper adjacent edges, which in dry
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conditions hides the opening. Floating flooring
consisting of small floorboards can thus be laid in
larger spaces especially if they are produced with a
locking system which allows at least some horizontal
5 movement along and/or towards the joint edges in locked
position Such a floor will in fact behave as a semi-
floating floor which utilizes both the movement of the
whole floor and movement within the locking system to
counteract changes in humidity.
10 The invention is based on a fourth understanding
that narrow floorboards will be considerably less curved
than wide floorboards as RH varies. This results in a
planer floor and easier installation.
The invention is based on a fifth understanding that
15 a flooring consisting of many small floorboards gives
better possibilities of providing a high laying quality
with invisible joint gaps. Laminate and wooden flooring
can, owing to an uneven moisture ratio in the board, be
laterally curved. Such a "banana shape" may cause visible
joint gaps. If the length of the boards is reduced, for
instance, from 1200 mm to 400 mm, the joint gap will be
reduced significantly. Narrow boards are also,easier to
bend, and in practice the mechanical locking system will
automatically pull the boards together and completely
eliminate the banana shape.
The invention is based on a sixth understanding
that the moisture problems that often arise in gluing of
wood blocks to a concrete floor can be solved by the wood
block being joined in a floating manner so that a mois-
ture barrier of plastic can be arranged between the
wooden floor and the concrete.
The invention is further based on a seventh under-
standing that a very convenient method of creating a
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natural parquet pattern consisting of wood blocks dis-
placed in parallel, is that the floorboards are made
narrow with a width and typically also with a length
corresponding to a parquet block.
The invention is based on an eighth understanding
that it is possible to provide a floor system which, for
instance, consists of small floorboards with preferably
the same width and preferably different lengths where the
length can be an even multiple of the width, and in which
floor system floorboards have mirror-inverted mechanical
locking systems. Such a floor system enables laying in
all the advanced patterns that can be provided with
traditional parquet blocks. Laying can take place
considerably more quickly and with better accuracy. Such
a floor system can produce advanced patterns also with a
surface layer which in traditional use can only be used
in a few variants. A surface layer of needle felt or
linoleum can, for instance, be glued to an HDF board. If
such. floor elements are manufactured in different color
variants and are machined to a floor system according to
the invention, joining of different floorboards in
different colors can give highly varying and advanced
patterns which cannot be provided with the original
surface layer.
Finally, the invention is based on the understanding
that a short side of a narrow floorboard must be able to
withstand the same load as a significantly longer short
side of a traditional floating floor. The reason is that
a point load on an individual row can be the same. For
instance, an 85 mm short side of a floor according to the
invention must thus be able to withstand the same load as
a 200 mm short side of a traditional floor. The short
side should suitably have a strength that withstands a
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tensile load of 100 kg or more. Joint systems that are
laid by downward angling of the short side, displacement
along the joint edge and downward angling of the long
side are particularly convenient for narrow boards. The
reason is that a joint system which is joined by angling
can be made stronger than a joint system which is joined
by snap action. The floorboards according to the
invention may have joint systems on long side and short
side which can be joined by downward angling.
Thus, the above means that according to the inven-
tion it is possible to provide small. floorboards, with a
format corresponding to traditional parquet blocks,
which, in a surprising manner and contrary to what has
been considered possible till now, may contribute to
giving advantages in floating flooring. These advantages
significantly exceed the known drawbacks.
The principles of the invention as described above
can also be applied to floor systems having other formats
than traditional parquet blocks. For example, stone
reproductions can be made in the formats 200 * 400 mm,
200 * 600 mm etc with. mirror-inverted joint systems which
can be joined by angling and/or snap action. These for-
mats can be joined in advanced patterns as stated above
long side against long side, short side against short
side or long side against short side.
These objects are wholly or partly achieved by
floorboards, flooring systems, blocks of floorboards and
methods for laying and manufacturing as set forth in the
independent claims. The dependent claims and the
description define embodiments of the invention.
Thus, according to a first aspect of the invention,
there is provided a rectangular floorboard for providing
a patterned floating flooring, said floorboard being
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provided, at least along opposing long edges, with inte-
grated connecting means for locking together said floor-
board with a second floorboard, such that upper edge
portions of said floorboard and said second floorboard,
in a joined state, together define a vertical plane. The
connecting means are adapted for locking together said
floorboard and said second floorboard in a horizontal
direction, perpendicular to said vertical plane, and the
connecting means are adapted for locking together said
floorboard and said second floorboard in a vertical
direction, perpendicular to a main plane of said floor-
board. The floorboard is distinguished in that a long
edge of said floorboard has a length not exceeding 80 cm
and a short edge of said floorboard (1) has a length not
exceeding 10 cm.
A flooring composed of such small floorboards will
provide an improved imitation of a classically patterned
parquet flooring, since the joints will be consistent
with the parquet blocks and not exhibit any pattern off-
sets or "additional" joints such as are exhibited by
known parquet and laminate floor boards. Thus, compared
with known parquet floorboards, the problem of two adja-
cent floorboards having mutually non-matching patterns
will be eliminated. Due to the integrated mechanical
locking system, the floorboards are easier to install
than floorboards for a classical parquet flooring.
According to one embodiment, the connecting means
may be adapted for locking together said floorboard and
said second floorboard at least by means of inward
angling, whereby upper joint edges contact each other.
The ability of the connecting means to allow for a
connection by an angling operation is advantageous since
a joint system which is joined by angling can be made
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stronger and easier to install than a joint system which
is joined by a snap action.
According to another embodiment, the connecting
means may be adapted for releasing said floorboard and
said second floorboard by means of upward angling, away
from a sub-floor. Such releasing or unlocking of the
floorboards facilitates laying, adjustment, replacement
and reuse of the floorboards.
According to another embodiment the second floor-
board may be substantially identical with said floor-
board. Thus, only one type of floorboard needs to be
produced in order to provide the flooring.
According to another embodiment the floorboard may
have a surface layer comprising a thermosetting resin. By
providing the floorboard with such a laminate surface, it
is possible to increase its wear resistance as compared
with the wood surface of strips for classically patterned
parquet floors.
According to another embodiment the floorboard may
have a surface layer comprising wood or wood veneer. A
surface layer of wood or wood veneer will provide the
appearance and feel of a real wood parquet floor, while
reducing the cost as compared with traditional parquet
floors. Thus, the floorboard core may be of any known
core material, such as wood slates, HDF, MDF, particle
board, plywood etC.
According to another embodiment the connecting means
may consist of a separate part, which projects from the
joint edge and which is mechanically joined with a core
of the floorboard. Such a separate part may be utilised
to instead of removing material from the edge of the
floorboard, thus reducing the amount of material waste.
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According to another embodiment the surface of the
floorboard may have a decoration and a shape corre-
sponding to a traditional parquet block with a length
of 30-80 cm and a width of 5-10 cm.
5 According to another embodiment, the joint edges
opposing each other in pairs on the long edges of the
floorboards may comprise a projecting locking element
integrated with the floorboard, and in that the opposing
second edge portion in the same pair comprises a locking
10 groove for receiving the locking element of an adjoining
floorboard.
According to another embodiment, a long edgeof said
floorboard may have a length exceeding 15 cm and a short
edge of said floorboard has a length exceeding 4 cm.
15 According to a second aspect of the invention, there
is provided a patterned floating flooring, a pattern of
which being provided by respective shapes of floorboards
constituting said patterned floating flooring. The
flooring is distinguished in that the patterned floating
20 flooring comprises the floorboards as described above.
According to a third aspect of the invention, there
is provided a block of floorboards for providing a floa-
ting flooring. The block of floorboards is distinguished
in that said block comprises at least two floorboards as
described above and in that these at least two floor-
boards are arranged such that at least one short edge of
a first of the at least two floorboards is aligned with
at least one short edge of a second of the at least two
floorboards.
Several variants of the invention are feasible. The
floorboards can be provided with all prior-art mechanical
joint systems. Special floorboards can be manufactured,
consisting of, for instance, 9 floorboards according to
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the invention which are joined in three rows displaced
in parallel. The short sides are thus not straight but
consist of displaced rows. Such floorboards can be laid
by a combination of downward angling of the long side,
lateral displacement and snapping-in of the short side.
The other embodiments can also be laid by inward angling
of the short side, lateral displacement and downward
angling. Finally, also different combinations of
snapping-in or insertion along the joint edge of a long
side or short side, lateral displacement and snapping-in
of another long side or short side can be used.
According to a fourth aspect of the invention, there
is provided a method for manufacturing a rectangular
floorboard, having long edges and short edges, said long
edges being provided with a locking system comprising
integrated connecting means for locking together said
floorboard with a second floorboard. The method comprises
steps of linearly displacing relative to each other a
floor element, sized and adapted for providing at least
two floor panels and a set of tools for machining a first
pair of opposing edge portions of the floor element, to
provide a final shape of at least part of said short
edges of said floorboard, dividing the floor element into
said at least two floor panels, and linearly displacing,
relative to each other, one of said at least two floor
panels and a set of tools for machining a second pair of
opposing edge portions of said floor panel, to provide at
least part of said locking system. The above described
production method is particularly suitable for
manufacturing small floorboards, such as the ones
described above.
This method enables rational manufacture of small
floorboards. Both the first and the second step can be
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performed in the same production line. If the floorboards
have the same locking systems on long side and short
side, the same set of tools can be used for both long
side and short side. Mirror-inverted A and B boards can
be made by the short side panel before sawing being turn-
ed through 180 degrees.
Fifth and sixth aspects of the present invention
provide respective flooring systems which consist of
floorboards with the same width but different lengths
which can be a multiple of the width. According to one
embodiment, the floorboards have mirror-inverted joint
systems which can be joined by inward angling. They can
be laid in many different patterns with long sides joined
with short sides. According to a different embodiment
there may be four different types of floorboards,
differing from each other with respect to length and/or
orientation of the locking system (normal - mirrored).
Seventh. and eight aspects of the invention provide
alternative methods for installing a flooring using
floorboards as described above. Using one of these
methods, quick and effective laying of a floor according
to the present invention can be carried out. According to
one alternative, the floorboard is joined at an angle
with the locking means in contact with each other, but in
a position that deviates from the final position when the
floorboards are lying flat on the sub-floor. The
floorboard is then displaced a distance corresponding to
its entire length relative to another floorboard in the
preceding row before the final locking takes place.
The above manufacturing and laying technique is
particularly suited for small floorboards, but may, of
course, advantageously also be used in floorboards with
other and larger formats.
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The invention will now be described in more detail
with reference to the accompanying schematic drawings
which by way of example illustrate embodiments of the
invention according to its different aspects.
Brief Description of th.e Drawings
Figs la-c illustrate prior-art floorboards.
Fig. 2 shows manufacture of laminate flooring
according to prior-art technique.
Figs 3a-f show examples of known mechanical locking
systems.
Figs 4a-a show a flooring according to the invention
Figs 5a-d show a joint system according to an
embodiment of the invention.
Figs 6a-d show a laying method according to the
invention.
Figs 7a-a show a laying method according to the pre-
sent invention.
Figs 8a-a illustrate a manufacturing method for
manufacturing floorboards according to the invention.
Figs 9a-f show a floor system according to the
invention.
Fig. 10 shows laying of floorboards according to the
invention.
Figs 11a-16e show examples of different patterns and
laying methods according to the invention.
Figs 17a-17c show examples of floor systems with
floorboards according to the invention in formats and
laying patterns that are convenient to resemble a stone
floor.
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Description of Embodiments of the Invention
Figs 4a-c illustrate floorboards 1, 1' whose long
sides 4a, 4b and short sides 5a, 5b are provided with
mechanical locking systems. The vertical locking means
may comprise, for example, a tongue groove 23 and a
tongue 22 (see Fig. 5a). The horizontal locking means may
comprise locking elements 8 which cooperate with locking
grooves 14. All floorboards are rectangular and have a
width corresponding to a traditional parquet block. Thus
the width is about one third of a traditional laminate
floorboard. In Fig. 4a, the surface of the floorboard has
the shape of a parquet block. In Fig. 4b, the surface has
a decorative surface layer consisting of two parquet
blocks, and in Fig. 4c the surface layer consists of
three parquet blocks. The surface layer can be laminate,
wood, plastic, linoleum, cork, various fiber materials
such as needle felt and the like. The surface can also be
printed and/or varnished.
Fig. 4d shows that such floorboards, which may thus
consist of one or more blocks, can be joined to a floor-
ing which in a natural way forms a brick-bond pattern.
All blocks, except those at the outer portions of the
floorboard, may have a full length. If the floorboard
consists of more than one block (Figs 4b, c) a certain
pattern alignment must take place in the production. On
the other hand, if the floorboard consists of a single
block according to Fig. 4a, no such pattern alignment is
necessary. The floorboard can be made by sawing a floor
element, which only has a pattern consisting of, for
instance, veneer with varying shades so as to resemble
wood blocks that are made from different logs of the same
kind of wood. In the flooring according to Fig. 4d, the
blocks are displaced a distance corresponding to half
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their length. Fig. 4e shows an example of a displacement
by one third of the length.
Figs 5a-d show that the waste can be reduced to
essentially the waste that arises in connection with
5 sawing if the joint system is formed with a separate
strip 6 which is mechanically fixed by a tongue 38 coope-
rating with. a tongue groove 36. Fixing can take place by
snapping into the joint edge of the floorboard 1 in such
a manner that the upper lip 20 and the lower lip 21 are
10 bent upwards and downwards respectively, when the strip
& is inserted towards the tongue groove 36 of the floor-
board 1. The locking element 37 cooperates with the lock-
ing groove 39. Joining of the strip 6 with the tongue
groove 36 can take place in many alternative ways. For
15 instance, the locking groove 39 can be formed in the
lower lip 21 and the locking element 37 can be formed in
the lower front part of the strip 6 so as to cooperate
with the locking groove 39. Joining of the strip 6 with
the joint edge of the floorboard can also take place by
20 inward angling of the strip 6 or snapping-in of the strip
6 in any upwardly angled position. This locking system
allows cost-efficient manufacture of narrow floorboards
without much waste. Fig. 5a shows an example of a lami-
nate floorboard 1, 1' with a wood fiber core 30 and a
25 surface layer 31 of laminate. In this embodiment the
separate strip 6 consists of wood fibers. The material of
the wood fiber based strip 6 could be solid wood,
plywood, particle board, fiberboard such as MDF, HDF,
compact laminate made of wood fibers impregnated with
thermosetting resin, or similar materials. Figs 5a, b
show a locking system which can be locked by inward
angling and snapping-in, and Figs 5c, d illustrate a
locking system which can locked by snapping-in. The
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projecting portion P2 of the strip 6 which extends beyond
the upper part of the join edges may in this embodiment
be equal or larger than the floor thickness T. This
facilitates locking with angling around the upper part of
the joint edges. A locking system which consists which
allows locking and unlocking by angling and which
consists of a separate strip is especially favorable on
the long side of a narrow floorboard.
Figs 6a-6d illustrate a laying procedure. The floor-
boards are rectangular and can be joined mechanically.
The laying operation begins, for example, with a first
row Rl being joined by, for example, the short sides of
the floorboards being angled together. The first row,
which may in fact be an optional row in the floor, con-
tams a floorboard G1 which is called the first board.
A second floorboard G2, in a second row R2 (Fig. 6a), is
arranged at an angle A to the first floorboard G1 and is
with its upper joint edge in contact with the joint edge
of the first floorboard G1. Fig. 6b shows that the laying
may be facilitated if a wedge-shaped tool WT is used as
a support. A new floorboard G3 in a second row R2 is
then locked together with its short side against the
short side of the second floorboard G2 in the second
row. This joining of short sides can take place by
insertion along the joint edge of the short side, by
inward angling or snapping-in against the joint edge of
the short side. During inward angling and preferably also
during snapping-in, this joining is carried out in such a
manner that the upper joint edge of the new floorboard G3
is positioned at a distance from the upper joint edge of
the first floorboard G1. During insertion along the joint
edge of the short side, this is not necessary since the
new board G3 can be inserted so as to contact the first
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board. The new board G3 can also first be joined with the
first G1 by snap action., after which it is laterally dis-
placed along the long side so that the short side is
snapped in against the short side of the second floor-
s board G2. Then both the new G3 and the second floorboard
G2 are laterally displaced (Fig. 6c) along their long
sides parallel to the first floorboard G1. The first
lateral displacement may be essentially equal to the
length 4a of the floorboard. A further new floorboard G3'
may then be joined according to Fig. 6d. When essentially
the entire row R2 has been filled, all floorboards are
angled downward and locked. Essentially the entire
installation can take place in this way.
Figs 7a-7e show the same laying seen from above.
When a new board G3, G3' and G3" after angling is dis-
placed, the second row R2 grows. This laying may be
repeated until the second floorboard G2 reaches the outer
part of the floor according to Fig. 7d. The main advan-
tage is that the entire row R2 can be laid without a
floor-layer needing to move along the floor rows. Owing
to the weight and flexibility of the floorboards, the
different upwardly angled floorboards will take different
angles. They may easily slide in a semi-locked state.
This is shown in Fig. 5b. The locking means 22, 23 and 8,
14 are not fully locked and this reduces friction while
at the same time the boards 1, 1' are prevented from
sliding apart by the locking element 8 being partly
inserted into the locking groove 14.
This method of laying is particularly suited for
small floorboards, but may also be used in larger. The
laying method renders it possible to automate laying.
Another advantage is that this laying method allows auto-
mated laying by means of a laying device. According to
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the invention, which thus also comprises a laying device
for floorboards, the floorboards can be laid using a
suitable device which, for instance, consists of the fol-
lowing parts and functions. The device has a store con-
s taming a number of new floorboards G3, G3' etc. These
floorboards are, for instance, stacked on each other. It
has a first inserting device which first inserts the new
board G3, at an angle to the first board G1 in the first
row R1. The inserting motion takes place along the short
sides so that the short sides of the second G2 and the
new G3 board will be mechanically locked. The device fur-
ther comprises a second inserting device which displaces
the two joined boards laterally parallel to the first row
R1. V~Then the device is moved from the first row R1, all
boards which have not yet reached a position parallel to
the sub-floor will finally be angled down towards the
sub-floor.
Fig. 8 shows a method for manufacturing a flooring
with mechanical joint systems. The floor element 2 is
sawn into new floor elements 2'. These floor elements
are then machined along their long sides, e.g. in
a machine with two chains. In this manner, a semimanu-
factured product in the form of a short side panel 2"
is manufactured. This machining, which thus is a rational
machining of the long sides of the floor element, in fact
forms the short sides 5a, 5b of the floorboards. After
this first machining, the short side panel 2" is sawn
into floor panels 3, the edges of which are then machined
along the long sides 4a, 4b, e.g, in a machine with only
one chain. The method is based on the fact that
manufacture, contrary to today's manufacture, takes place
by the long sides being machined last and a special saw-
ing or dividing operation taking place between machining
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of the short side of the floorboard and machining of its
long side. The method thus implies that the short sides
can be manufactured in a large format very rationally
even if the floorboards are narrow. Today's machines
operate with a lower capacity since machining of short
sides takes place by means of cams on chains and this
means that the boards are machined with a distance that
in Fig. 2 is designated D. The risk of angular errors
between long side and short side can be significantly
smaller than in traditional manufacture. Any lateral
crookedness that may arise in connection with sawing
into floor panels can be eliminated by the boards being
aligned with a ruler RL before the machining of the long
sides.
If the floorboard has a width of 85 mm and a length
of 6 * 85 = 510 mm, the machining of the long sides will
require a machining time which is six times longer than
the machining of the short sides. An efficient production
line may consist of a short side machine and a sawing
unit and a plurality of long side machines, for instance
six.
Mirror-inverted locking systems can be provided by,
for instance, the short side panel 2" before sawing being
rotated in the horizontal plane through 180 degrees.
Alternatively, the floor panel 3 can be rotated corre-
spondingly after sawing.
Machining of long sides and short sides may take
place in one and the same machine and using the same set
of tools. Several variants are feasible. For instance the
long sides may be machined first. The floor element then
has a length corresponding to several floorboards and a
width corresponding to one floorboard. After the first
machining, the floor element is divided into several
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floor panels, the edges of which are then machined along
the short sides.
Figs 9a-9e show a floor system which consists of two
different board formats with mirror-inverted mechanical
5 locking systems which can be joined by inward angling on
long sides and short sides.
Fig. 9a shows a locking system which in this
embodiment is made integrally in one piece with the core
of the floorboard and which is so designed that a long
10 side can be joined with a short side. The vertical
locking is obtained by a tongue 22 and a groove 23. The
horizontal locking is accomplished with a strip and a
locking element 8 on one of the floorboards 2 cooperating
with a locking groove 12 on the other floorboard 1'. It
15 is an advantage if the locking system is essentially
identical on both long side and short side. In this
embodiment, the locking system is identical. However, it
should be pointed out that the invention can also be
applied to floorboards with different locking systems
20 and/or locking systems containing separate or different
materials than the core. Such differences can exist
between different floorboards and/or long side and short
side. The locking system can be joined by inward angling.
In this embodiment, the locking system withstands a high
25 tensile load corresponding to about 100 kg in a locking
system having an extent along the joint edge of 100 mm.
The locking element 8 has a considerable extent
vertically vT and horizontally HT. In this embodiment,
the vertical extent VT is 0.1 times the floor thickness T
30 and the horizontal HT 0.3 times the floor thickness T.
Fig. 9b shows a floorboard 42A having a width 1M and
a length 6M which is 6 times the width. It may be an
advantage if the dimensional accuracy can be less than
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0.1 mm and maybe even within the tolerance of 0.05 mm or
lower. With modern machines, it is possible to achieve
tolerances of 0.02 mm. Fig. 9c shows an identical
floorboard 41B, with the difference that the locking
system is mirror-inverted. 41A and 41B have short sides
with the same tongue side 22 and groove side 23. The long
side of the floorboard 41A has a tongue side 22 on the
side where the floorboard 42B has a groove side. Thus the
locking systems are mirror-inverted.
Such a flooring system allows laying in advanced
patterns since long sides can be joined with short sides
and the direction of laying can be varied. The module
system with the length as an exact multiple of the width
increases the possibilities of variation,
Figs 9d and 9e show corresponding floorboards with
a length 9M which in this embodiment is, for instance,
9 times the width 1M. Moreover, if the floor system
consists of boards with different lengths, still more
advanced patterns can be provided.
It is obvious that a number of variants are feasible
within the scope of the above principles. Fig, 9f shows
two short sides 5a and 5b of two adjacent edges of
floorboards. In this embodiment there is only a
horizontal locking consisting of a strip 6, locking
element 8 and a locking groove 12. Such floorboards could
have a locking system on long sides as shown in fig. 5a
and they could be installed in parallel rows. If the
floorboards have mirror inverted locking system as
described above, they could be installed in a herringbone
pattern long side to short side. Floorboards can be made
in many varying lengths and widths. The floor system may
consist of three floorboards or more with different sizes
and the floorboards may have the same width but random
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lengths. Some floorboards can have the width measure 1M
and others 2M or more. Nor do the floorboards have to
have parallel sides. For instance, the short sides can be
made at an angle of 45 degrees to the long sides. Such
manufacture can be carried out rationally in a machine
with two chains where the cams of the chains are
displaced so that the boards will pass the milling tools
at an angle of e.g. 45 degrees. Also other optional
angles can be made in this manner.
Fig. 10 shows examples of how floorboards 41A can
be joined by inward angling long side against short side
with an already laid floorboard 42B. According to the
invention, the long sides of the floorboards 41A are
joined by inward angling. Such a floorboard, referred to
as second floorboard 41A, is in the initial phase of the
laying in an upwardly angled position relative to a
first, previously laid floorboard 42B in the first row.
A short side of this second floorboard 41A is in contact
with the long side of the already laid first floorboard
42B. It is an advantage if a support WT is used to hold
this and the already laid floorboards in the second row
in an upwardly angled position. A new floorboard 41A' is
angled with its long side against the second floorboard
41A in the second row which is perpendicular to the first
laid floorboard 42B. The new floorboard 41A which is
locked to the second floorboard 41A is then displaced
along the joint edge in the locked position until its
upper short side edge comes into contact with the long
side edge of the first board 42B. Subsequently, the
entire second row of floorboards 41A, 41A' is angled
down towards the sub-floor. If a suitable laying order is
applied, advanced patterns can be laid with this angle-
angle method, The joint system obtains great strength and
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large floors can be laid without expansion joints between
floor sections.
Fig. 11a shows how floorboards 41A and 42A of diffe-
rent lengths can be combined to a floor unit FU in a
floor system so that all rows will be of the same length
and the entire floor unit FU will have a locking system
on all sides.
Figs 11b and 11c show how the length of the floor
unit FU can be varied by combining the boards of diffe-.
rent lengths. The length of the floor unit can be changed
in steps which are half the length of the shortest board.
The width can be varied by the number of rows according
to Fig. 11c.
Fig. 12a shows that the floor unit FU can be adjust-
ed to the size of the room so that a decorative frame of
sawn boards 41a can be formed, which can be used to make
the final adaptation of the floor to the size of the
room. To create the decorative pattern, floorboards with
mirror-inverted locking systems 41A and 41B are used. 01-
04 indicate a laying order which can be used to join the
floorboards using the angle-angle method. After
installing the floor unit FU in parallel rows with boards
of different lengths, a mirror-invested board 41B is
joined with the short sides of the floor unit 02. This
board has a length which in that alternative corresponds
to the width of six floorboards. Then the vertical rows
03 axe joined by the angle-angle method and finally the
laying of the floor is terminated by the horizontal rows
04 also being locked in the same way.
This and other patterns can, of course, also be
joined by the combination of angling, displacement and
snapping, or merely snapping, displacement and snapping.
Also insertion along the joint edge can be used. A
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locking system on short sides without a tongue as shown
in fig 9f allows installation with only angling of the
long sides
Fig 12b shows a variant which in this embodiment
comprises a plurality of mirror-inverted boards 41B. The
laying can be effected in the same way as above, for
instance according to the laying order 01-09.
One condition for the above laying of the floor to
be done with high quality without large visible joint
gaps is that the floorboards are manufactured with great
dimensional accuracy. It is advantageous if each joint
can be given a certain degree of flexibility so that the
manufacturing tolerances are balanced. A play P between
the locking surfaces of the locking element 8 and the
locking groove 12 of e.g. 0.05 mm, as shown in fig. 9a
and 9f, is advantageous in this context. Such a play P
does not cause a visible joint gap. Beveling 133 of upper
joint edges can also be used to conceal a joint gap and
also to remove parts of the hard surface layer so that
the upper joint edges will be more flexible and can be
compressed.
Fig. 13a shows another pattern which can be laid
according to the angle-angle method in the order O1-07.
The pattern can be created with only one type of boards
which need not have mirror-inverted joint systems.
Figs 14a-b show a diamond pattern with offset dia-
monds that can be laid by first joining floorboards to
two floor units FU 1 and FU 2. Then these two floor units
are joined with each other by, for instance, inward
angling.
Figs 15a-c show alternative patterns which can be
created with a floor system and laying methods as
described above.
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Figs 16a-b show herringbone patterns which can be
joined by the long sides being angled inwards and the
short side being snapped against the long side. Laying
can be carried out in many different ways for example
5 with only angling of long sides. In Fig. 16, the floor is
laid with both groove side 23 and tongue side 22 in the
laying direction ID. It is still more convenient if
laying takes place with merely the groove side 23 in the
laying direction according to Fig. 16b.
10 Figs 16c-a show herringbone patterns with two and
three blocks.
Figs 17a-c show how the corresponding patterns can
be created with floorboards having a format which, for
instance, resembles stone. The floorboards have a deco-
15 rative groove DG on one long side and one short side
which is made, for example, by part of the outer deco-
rative layer being removed so that other parts of the
surface layer that are positioned under the decorative
layer, or the core, become visible.
20 Fig. 17c show how mirror-inverted floorboards can be
joined in advanced patterns where the decorative groove
after installation frames the floorboards.
It is noted that the invention may be applied to
even smaller boards, blocks or strips than those
25 described above. Such strips may e.g. have a width of 2
cm and a length of 10 cm. The invention may also be used
to produce very narrow floor panels, for instance of
about 1 cm or less, which could be used to connect
different floor units or as decoration.
