U.S. patent application number 10/708314 was filed with the patent office on 2004-10-21 for floorboard and method for manufacturing thereof.
This patent application is currently assigned to VALINGE ALUMINIUM AB. Invention is credited to Pervan, Darko.
Application Number | 20040206036 10/708314 |
Document ID | / |
Family ID | 33304046 |
Filed Date | 2004-10-21 |
United States Patent
Application |
20040206036 |
Kind Code |
A1 |
Pervan, Darko |
October 21, 2004 |
FLOORBOARD AND METHOD FOR MANUFACTURING THEREOF
Abstract
Floorboards with a surface of flexible fibers for laying a
mechanically joined floating floor, and methods for manufacturing
and profloorings containing such floorboards.
Inventors: |
Pervan, Darko; (Viken,
SE) |
Correspondence
Address: |
BURNS DOANE SWECKER & MATHIS L L P
POST OFFICE BOX 1404
ALEXANDRIA
VA
22313-1404
US
|
Assignee: |
VALINGE ALUMINIUM AB
Ostermalmsgatan 82
Stockholm
SE
|
Family ID: |
33304046 |
Appl. No.: |
10/708314 |
Filed: |
February 24, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60456957 |
Mar 25, 2003 |
|
|
|
Current U.S.
Class: |
52/578 |
Current CPC
Class: |
E04F 2201/0517 20130101;
E04F 15/02194 20130101; E04F 2201/05 20130101; B27F 1/04 20130101;
E04F 15/02038 20130101; E04F 15/041 20130101; E04F 15/105 20130101;
B32B 2471/00 20130101; B27M 3/08 20130101; B32B 5/26 20130101; E04F
2201/0153 20130101; B32B 3/06 20130101; E04F 15/04 20130101; E04F
15/042 20130101; B27F 1/06 20130101; B27M 3/04 20130101; B32B 21/10
20130101; E04F 15/102 20130101; E04F 15/181 20130101; E04F 2201/03
20130101; E04F 15/107 20130101; Y10T 29/49616 20150115; Y10T
29/49623 20150115; A47G 27/0293 20130101; E04F 2201/023 20130101;
B32B 2307/102 20130101; E04F 15/186 20130101; E04F 2201/026
20130101 |
Class at
Publication: |
052/578 |
International
Class: |
E04F 015/22 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 24, 2003 |
SE |
0300479-3 |
Mar 17, 2003 |
SE |
0300626-9 |
Claims
1. Floorboards comprising a surface layer and a core, for making a
floating flooring, which floorare mechanically lockable and which
along their edge portions have pairs of opposing connectors for
locking similar, adjoining floorboards to each other both
vertically and horizontally, wherein the surface layer comprises
flexible resilient fibers.
2. Floorboards as claimed in claim 1, wherein the core of the
floorboard contains wood fibers.
3. Floorboards as claimed in claim 1, wherein the surface layer is
made of needle felt.
4. Floorboards as claimed in claim 1, wherein the surface layer has
a density below 400 kg/m.sup.3.
5. Floorboards as claimed in claim 1, wherein the floorboards are
rectangular or square and that two opposite sides can be joined by
inward angling, whereby upper adjoining joint edge portions are in
contact with each other.
6. Floorboards as claimed in claim 5, wherein the upper adjoining
joint edge portions of the floorboards are compressible and can be
changed in shape in connection with joining.
7. Floorboards as claimed in claim 1, wherein the surface layer
consists of flexible resilient fibers.
8. A method for manufacturing floorboards with a surface layer and
a core, for making a floating flooring, which floorboards are
mechanically lockable and which along their four edge portions have
pairs of opposing connectors for locking adjoining floorboards to
each other both vertically and horizonally, for providing a
floating floor with mechanically lockable floorboards, the method
comprises: joining a surface layer of flexible and resilient fibers
to a wood-fiber-based core to form a floor element, linearly
displacing the floor element and a set of tools for machining the
joint edges of the floor element, to provide at least part of the
upper joint edges of the floor panel.
9. The method as claimed in claim 8, wherein the set of tools
consists of a set of knives and a set of rotary milling tools.
10. A floorboard, for providing a floating flooring, the floorboard
having a surface layer and a core, the floorboard, along at least
one pair of opposing edge portions, having pairs of opposing
connectors for locking said floorboard to a similar, adjoining
floorboard both vertically and horizontally, wherein the surface
layer consists substantially of flexible resilient fibers.
11. The floorboard as claimed in claim 10, wherein a second pair of
opposing edge portions has pairs of opposing connectors for locking
said floorboard to a similar, adjoining floorboard vertically or
horizontally.
12. The floorboard as claimed in claim 10, wherein a second pair of
opposing edge portions has pairs of opposing connectors for locking
said floorboard to a similar, adjoining floorboard vertically and
horizontally.
13. A method for manufacturing floorboards with a surface layer and
a core, for making a floating flooring, which floorboards are
mechanically lockable and which along at least one pair of opposing
edge portions have pairs of opposing connectors for locking
adjoining floorboards to each other both vertically and
horizontally, for providing a floating floor with mechanically
lockable floorboards, the method comprising: joining a surface
layer comprising flexible and resilient fibers to a
wood-fiber-based core to form a floor element, linearly displacing
the floor element relative to a set of tools for machining the
joint edges of the floor element, to provide at least part of the
upper joint edges of the floorboard.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of Swedish Patent
Application No. SE 0300479-3, filed in Sweden on Feb. 24, 2003, and
U.S. Provisional Application No. 60/456,957, filed in the United
States on Mar. 25, 2003. The contents of SE 0300479-3 and U.S.
60/456,957 are incorporated herein by reference.
BACKGROUND OF INVENTION
[0002] 1. Technical Field
[0003] The invention relates generally to the technical field of
floorboards. The invention concerns floorboards with a
sound-absorbing surface of fibers which can be joined mechanically
in different patterns. The invention also concerns methods for
manufacturing such floorboards. The invention is particularly
suited for use in floating floors.
[0004] 2. Field of Application
[0005] The present invention is particularly suited for use in
floating floors with mechanical joint systems. Such floors often
consist of a surface layer of laminate or wood, a core and a
balancing layer and are formed as recfloorboards intended to be
joined mechanically, i.e. without glue, along both long sides and
short sides in the vertical and horizontal direction.
[0006] The following description of prior-art technique, problems
of known systems, as well as the object and features of the
invention will therefore as non-limiting examples be aimed mainly
at this field of application. However, it should be emphasized that
the invention can be used in optional floorboards which have a
surface layer and a core. The invention may thus also be applicable
to floors that are nailed or glued to a base.
BACKGROUND OF THE INVENTION
[0007] Floating floors with mechanical joint systems and with a
surface of laminate or wood have in recent years taken large shares
of the market from, for instance, carpets and plastic flooring but
also from wooden flooring that is glued to the base. One reason is
that these floors can be laid quickly and easily on a subfloor that
does not have to be perfectly smooth or flat. They can move freely
from the subfloor. Shrinkage and swelling occur under the
baseboards and the joints between the floorboards are tight. A
floating floor with a mechanical joint system can easily be taken
up and laid once more. Individual floorboards can be replaced, the
subfloor is accessible for renovation and the entire floor can be
moved to a different room.
[0008] Plastic floors and textile floor coverings that are glued to
the subfloor require a perfectly flat subfloor. Laying is
complicated and the flooring cannot be removed without being
damaged. Such floorings are advantageous since they can be supplied
in widths of for instance 4 m. There are few joints. Plastic
floorings are impermeable to water, and both plastic flooring and
textile flooring are soft and produce a lower sound level than
laminates and wooden floors.
[0009] Thus, floating floors have many advantages over floors that
are glued to the subfloor. A great drawback of such floating floors
with a hard surface of wood or laminate is, however, that they
produce a high sound level with people walking on the floor. The
sound level can be annoying especially in public places, such as
offices, hotels and business premises where there are many people
walking around. It would be possible to use floating floors to a
greater extent if the sound level could be reduced.
DEFINITION OF SOME TERMS
[0010] In the following text, the visible surface of the installed
floorboard is called "front side", while the opposite side of the
floorboard, facing the subfloor, 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 preferably 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 semi-manufacture,
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 layers" are
meant all layers applied to the core closest to the front side and
covering preferably the entire front side of the floorboard. By
"decorative surface layer" is meant a layer which is essentially
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
flooring that is available on the market under this designation.
The wear layer of the laminate flooring consists as a rule of a
transparent sheet of paper which is impregnated with melamine
resin, with aluminum oxide added. The decorative layer consists of
a melamine impregnated decorative sheet of paper. The core is as a
rule a wood-fiber-based sheet. By "HDF" is meant sheet material
that is known on the market under the designation high density
fiberboard, HDF, consisting of ground wood fibers joined by a
binder. When a HDF sheet is manufactured with a lower density, it
is called MDF (Medium Density Fiberboard).
[0011] 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 several "joint
surfaces" which can be vertical, horizontal, angled, rounded,
beveled etc. These joint surfaces exist on different materials, for
instance laminate, fiberwood, plastic, metal (especially aluminum)
or sealing material. By "joint" or "locking system" are meant
coacting connecting means which connect the floorboards 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
joint systems can in many cases also be joined by means of glue. By
"floatng floor" is meant flooring with floorboards which are only
joined with their respective joint edges and thus not glued to the
subfloor. 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 "textile
floor" is meant a soft flooring which consists of oil-based
synthetic fibers or natural fibers joined to form a carpet or felt.
The flooring is usually produced in a width of about 4 m and a
length that can be several hundred meters. The flooring is
delivered from the factory usually in rolls and is usually
installed by gluing to a subfloor. By "needle felt" is meant a
fiber-based felt which is sold on the market under the designation
needle felt carpet. This floor consists of oil-based fibers of e.g.
polypropylene (PP), nylon (PA) or polyester (PES) which are joined
to form a felt. Joining takes place by a fiber mat being punched by
means of hooked needles. The rear side is usually coated with foam
which may consist of latex and chalk.
PRIOR-ART TECHNIQUE AND PROBLEMS THEREOF
[0012] To facilitate the understanding and the description of the
present invention as well as the knowledge of the problems behind
the invention, a description of prior-art technique now follows.
Floorboards which in the following are referred to as rectangular
with long sides and short sides can also be square.
[0013] Hard floorings with a surface of laminate or wood cause a
high sound level. The high sound level arises mainly as people walk
on the hard laminate or wood surface. The sound that is produced at
the surface causes a high sound level in the room. The sound also
penetrates the floor and into the beams and joists. To solve this
problem, floating floors have been installed on a base of
cardboard, felt, foam or like materials. The reduction of sound
thus occurs on the rear side of the floorboard by means of special
underlay materials that are applied between the floating flooring
and the subfloor. This can cause a considerable dampening of the
sound level between two floor levels. The reduction of sound that
can be achieved in the room is of a limited extent.
[0014] Another method of reducing the sound level is to glue the
floorboards to the subfloor. This results in a certain reduction of
sound in the room, and the sound frequency is felt to be more
pleasant. The costs are high and the laying quality is poor, with
many and large joint gaps. A third method is to provide the surface
of the floorboard with a surface layer of e.g. cork. This mate is
softer than wood and laminate and reduces the sound level. A cork
floor, however, suffers from a number of drawbacks. Durability and
impression strength are relatively low, cost is high and sound
reduction may be insufficient.
SUMMARY OF INVENTION
[0015] An object of the present invention is to provide floorboards
which can be joined mechanically to form a floating flooring with a
low sound level. Such a flooring should at the same time have an
attractive appearance and allow manufacture with great
accuracy.
[0016] The invention is based on a first understanding that a low
sound level should above all be provided using a surface layer
which does not produce a high sound level when being hit with hard
materials on its surface.
[0017] The invention is based on a second understanding that
floorboards with a soft surface layer having a low density have a
lower sound level than floorboards with surface layers that are
hard and have a high density.
[0018] The invention is based on a third understanding that it is
possible to provide a surface layer at a low cost, which is sound
absorbing and has high durability and impact strength. Such a
surface layer should consist of fibers that are flexible and which
can be compressed when the floor is subjected to a load, for
instance with people walking on its surface. These fibers can be
made of materials having a relatively high density and being very
strong, for instance synthetic fibers or natural fibers such as
wool. When the fibers are thin and joined to form a felt or a
carpet with air between the flexible fibers, a surface layer is
produced which is soft and has low density. The thickness of the
fibers may be, for instance, 0.05-0.10 mm. The volume density of
the surface layer can be below 400 kg/m.sup.3, and it can
preferably have a density of 150-300 kg/m.sup.2. This is
considerably lower than wood, laminate and cork and the sound level
is significantly lower than for all these materials.
[0019] The invention is based on a fourth and highly surprising
understanding that a fiber-based surface layer with low density,
for instance in the form of a needle felt mat, can be applied by,
for instance, gluing to a core of e.g. fiberboard. The core can be,
for instance, a particle board, MDF or HDF. This floor element can,
for instance, by sawing be divided into floor panels which are
machined using, for instance, a combination of rotary knives and
diamond tools so that they form floorboards in a floating floor.
The upper joint edges can be formed in such a manner that, at the
surface, they consist mainly of free fibers and closest to the
core, fibers joined to the core. The surface layer can then be
manufactured with great accuracy and without loose fibers. The
fibers closest to the core can be joined by mixing with a flexible
material, such as latex. This gives the surface layer better
stability and facilitates cleaning since dirt cannot penetrate into
the lower parts of the surface layer. Thin surface layer will be
easier to handle if they are integrated with a core.
[0020] The invention is based on a fifth understanding that these
floorboards can be joined by means of a mechanical joint system
which on the one hand positions the floorboards with great accuracy
relative to each other and which at the same time holds upper joint
edges in close contact. The joints between the floorboards will be
very tight and they can be made essentially invisible to the
eye.
[0021] The invention is based on a sixth understanding that a
floating floor with a fiber surface can be installed quickly and
rationally and at a cost that does not have to exceed the cost of
putty-coating of subfloors and gluing and cutting of a textile
floor covering. Attractive patterns can be provided, for instance,
by floorboards with different formats and different colors of the
surface layer being joined to each other with an exact fit.
Attractive patterns can be created, for instance with a surface of
needle felt which normally does not allow very great variation in
pattern. Thin fiber layers, for instance 1-2 mm, which are
integrated with a smooth core, can provide a perfectly smooth
floor. For instance, when a needle felt carpet is glued to a
fiberboard, the surface will be highly stable as to shape. This
facilitates, for example, printing of advanced patterns on the
fiber surface. Durability increases if the surface is flat without
rises.
[0022] The invention is based on a seventh understanding that a
floating floor with a sound-absorbing fiber surface and a
mechanical joint system is easy to take up. Such a floor is
particularly convenient for temporary exhibitions, business
premises and the like, in which the floor is changed frequently,
and in premises subjected to great wear. Floorboards in connection
with, for example, entrance portions, in which wear and soiling is
great, can easily be exchanged.
[0023] Finally, the invention is based on an eighth understanding
that floors with different surface layers can be provided with
mechanical joint systems so as to be joinable to each other. In
this way, combination floors can be provided which, for instance,
consist of laminate floor and needle felt floor. If the floorboards
have a similar thickness, the floor will be smooth. In walking
areas, such a floor can have a surface of needle felt in order to
dampen the sound level. The other surfaces may consist of, for
instance, floorboards with a surface of laminate, linoleum, wood or
plastic. These surfaces are easy to clean, and suitable
combinations of materials can provide an attractive design.
[0024] The above thus means that according to the invention it is
possible to provide a floor having all the advantages of a floating
laminate or wooden floor while at the same time one of the major
drawbacks can be eliminated by means of a surface layer of fibers
that does not generate a high sound level.
[0025] This object is achieved wholly or partly by floorboards and
a method for manufacturing that are evident from the independent
claims. The dependent claims define particularly preferred
embodiments of the invention.
[0026] According to a first aspect, in one embodiment, the present
invention comprises rectangular or square floorboards for making a
floating flooring, which floorboards are mechanically lockable and
which along their edge portions have pairs of opposing connecting
means for locking of adjoining floorboards to each other both
vertically and horizontally (D1 and D2 respectively), wherein the
surface layer of the floorboards consists of flexible and resilient
fibers.
[0027] In this context, the term "consists of" should be
interpreted as "consisting substantially of", taking into account
that the surface layer, in addition to the fibers, may also
comprise e.g. fiber binders, backing layers, fiber treatment agents
(for repelling dirt, flame retardants etc.) or matter resulting
from printing of the surface.
[0028] According to a preferred embodiment of this first aspect,
the floorboards can be provided with a surface layer which consists
of needle felt with a density below 400 kg/m.sup.3.
[0029] Several variants of the invention are feasible. The
floorboards can be provided with any prior-art mechanical joint
system. Examples of prior-art mechanical joint systems are provided
in WO94/26999, WO97/47834, WO99/66151, WO99/66152, FR-2WO02/055809,
WO02/055810 and WO 03/083234. Such floorboards can be laid by
different combinations of angling, horizontal snapping-in, vertical
snapping-in, or folding and insertion along the joint edge. The
floorboards can also have mirror-inverted joint systems that allow
joining of long side to short side or optional sides if the boards
are square.
[0030] According to a second aspect, in one embodiment, the present
invention comprises a method for rational manufacture of
floorboards as described above. According to this method, a surface
layer consisting of flexible fibers are joined to a core in order
to form a floor element. Joining can occur, for example, by gluing,
and the core may consist of a wood-fiber-based material such as
HDF, MDF, particle board, plywood etc. This floor element is then
sawn up and machined to a floorboard using a rotary tool. This
means that the manufacturing technique is characterized in that the
surface layer is formed by machining in connection with the
finishing of the joint edges of the floor panel.
[0031] The embodiments of the invention will now be described in
more detail with reference to the accompanying schematic drawings
which by way of example illustrate currently preferred embodiments
of the invention according to its various aspects.
BRIEF DESCRIPTION OF DRAWINGS
[0032] FIGS. 1a-d illustrate manufacture of a floorboard according
to an embodiment of the invention.
[0033] FIGS. 2a-d show examples of mechanical joint systems which
can be used in embodiments of the invention.
[0034] FIGS. 3a-c show an embodiment of the invention.
[0035] FIGS. 4a-f illustrate the manufacture of the joint edge
portion according to an embodiment of the invention.
[0036] FIGS. 5a-c show a flow consisting of floorboards with
different surface layers according to an embodiment of the
invention.
[0037] FIGS. 6a-d show embodiments of floors according to the
invention.
[0038] FIGS. 7a-e show embodiments off floors and locking systems
according to the invention.
DETAILED DESCRIPTION
[0039] FIGS. 1a-d illustrate the manufacture of a floorboard
according to an embodiment of the invention. A layer 31, which in
this embodiment consists of needle felt, is joined, for instance,
by gluing to a core 30. This core may consist of, for example,
particle board, fiberboard, such as MDF, HDF, plywood or the like.
A lower layer, for instance a balancing layer 32, can be applied to
the rear side to prevent cupping. This rear layer can also be a
soft material, such as foam, needle felt, cardboard or the like,
which levels irregularities in the subfloor and which improves the
reduction of sound. This lower layer is in some applications not
necessary. The floor element 3, which may have a thickness of e.g.
5-20 mm, is then divided into a plurality of floor panels 2. These
panels are then machined and joint edge portions are formed so as
to constitute a mechanical joint system 7, 7'. An example of such a
joint system on the long sides 4a and 4b is shown in FIG. 1d. The
floorboards could be produced in several alternative ways. For
example the surface layer 31 and/or the balancing layer 32 could be
applied on the core of the floor panels and not on the core of the
floor elements.
[0040] FIGS. 2a-d show examples of mechanical joint systems which
can be used in the invention. The joint system according to FIG. 2a
can be joined by vertical snapping-in. In the joint system
according to FIGS. 2b and 2c, a groove 36 and a tongue 38 form the
vertical joint D1. A strip 6, a locking element 8 and a locking
groove 14 form the horizontal joint D2. These locking systems can
be joined by angling and horizontal snapping-in. If upper joint
edges 41, 42 are compressible, the joint system in FIG. 2c can be
locked by vertical snapping-in. If the tongue 32 is removed, the
locking could be accomplished with vertical folding without any
snapping. A surface layer 31, which consists of e.g. needle felt,
can be pressed together, and this facilitates vertical snapping-in.
FIG. 2d shows a different embodiment which can be joined by angling
and snapping-in. Upper joint edges 41, 42 have in this embodiment a
beveled portion.
[0041] In one embodiment, the floorboard, on a first pair of
opposing joint edges, is provided with a mechanical locking system
adapted for locking the floorboard to an adjoining floorboard both
vertically D1 and horizontally D2. This first pair of opposing
joint edges may be the floorboard's long edges. A second pair of
opposing joint edges may be provided with a mechanical locking
adapted for locking the floorboard to an adjoining floorboard
vertically and/or horizontally. This second pair of opposing joint
edges may be the floorboard's short edges.
[0042] In one embodiment, the second pair of opposing joint edges
are provided with a mechanical locking system which only provides
locking in the vertical direction, such as is the case with a
prior-art tongue-and-groove system.
[0043] In another embodiment, the second pair of opposing joint
edges are provided with a mechanical locking system which only
provides locking in the horizontal direction, such as would be the
case if the tongue 38 of any one of the embodiments of FIGS. 2b or
2c was to be removed, while leaving the locking strip 6 with its
locking element 8 and the locking groove 14. In FIG. 2d such a case
would be accomplished if the tonge 38 or the lower lip 39 will be
removed.
[0044] FIGS. 3a-c illustrate a floorboard which in this embodiment
has a core 30 of a relatively soft material, such as MDF or
particle board. The locking system has been adjusted to the soft
core by the locking element 8 having a horizontal extent which is
about 0.5 times the thickness of the core 30. The surface layer 31
has outer joint edges 40, 41 which in this embodiment project
beyond the outer parts of the core 30. This projection can be some
tenths of a millimeter. The outer parts of the surface layer are
pressed together in connection with laying, and the floorboards
will have very tight joints. The mechanical locking system guides
the floorboards in exact positions and ensures a high quality of
laying. In one embodiment the locking system may have a geometry
where a play may exist, between the locking surface 9 of the
locking element 8 and the locking groove 14, when the floorboards 1
and 1' are pressed together. The core 31 can have a thickness of
e.g. 6-7 mm, and the surface layer 31 can have a thickness of 1-2
mm. In this embodiment, the total thickness of the floorboard can
thus be about 7-9 mm, and the floor can then be joined to ordinary
laminate floors having a thickness of about 7-8 mm. Other
thicknesses can also be used in this invention.
[0045] FIGS. 4a-4f illustrate how joint edge portions can be
machined. We have discovered that a soft surface layer of fibers
cannot be machined accurately by means of cutting rotary tools
which are normally used in manufacture of laminates and wooden
floors and the wood-based core materials that are the most common
ones in these cases. Loose fibers, especially in corner portions,
cause a frayed joint edge. Plastics that are used in manufacture of
synthetic fibers have as a rule a melting point round 120-160
degrees C. The fibers melt at high machining speeds. These problems
can be solved by the surface layer being cut using, for instance,
knives. These knives TP1A and TP1B can be rotary. The angle of
action of the knives is indicated by the arrows R1a and R1b in
FIGS. 4a, 4b. The knives, which can have other angles than the 90
degrees as shown, cut against the core 30, and in this embodiment
the cut is placed outside the upper and outer part of the core in
the completed floorboard. FIGS. 4a-f show that the entire joint
system can be formed using merely 4 milling tools TP2A, TP2B, TP3A
and TP3B which machine the core. The joint system in the shown
embodiment is made in one piece with the core. It is also possible
to make the whole, or parts of, the joint system of a material
other than that of the core of the floorboard. For instance the
strip 6 can be made of aluminum or of a sheet-formed blank which is
machined to a strip and mechanically attached to the joint
edge.
[0046] FIGS. 5a-c show floorboards with two surface layers. The
floorboards 1, 1' can, for instance, have a surface layer of
laminate or wood, and the floorboards 2, 2' can have a surface
layer of e.g. needle felt, linoleum, plastic of some other suitable
material. Also other combinations of materials may be used. FIGS.
5b and 5c show that joining to outer upper parts can take place,
which are essentially positioned in the same plane. No transition
strips are required.
[0047] In an alternative design, the fibers of the surface layer 31
may extend vertically such that the floorboard having the fiber
surface layer appears slightly higher than the adjacent, normal
floorboard. Hence, the vertical extension of the fiber surface
layer may be used to provide a desired surface structure of the
flooring, e.g. in order to provide the appearance of a rug being
placed on a hard floor.
[0048] FIGS. 6a-6d show examples of floors that can be provided
according to the invention. In FIG. 6a, the floorboards 2, 2' have
a surface of needle felt. They can be square, for instance
40.times.40 cm. The floorboards 1, 1' can have a surface of
laminate, wood, cork, linoleum, plastic etc. For example they can
have a width of 10 cm and a length of 40 cm. In FIG. 6b, the
squares are offset. If the harder floorboards 1, 1' are positioned
at a somewhat lower level than the softer floorboards, the hard
floorboards will not cause a high sound level since they will, to a
limited extent, be in contact with shoes generating sound. Thus,
the invention also concerns a set of floorboards with at least two
different surface layers to provide a floor.
[0049] FIGS. 6c and 6d illustrate floors consisting of two
different floorboards with surface layers of flexible fibers which
differ from each other with respect to color, surface structure
etc. In FIG. 6c, the floorboards are joined to form a herringbone
pattern. They have mirror-inverted mechanical locking systems that
allowjoining of long side to short side by angling and/or
snapping-in. The long sides can also be joined by angling and /or
snapping-in. If the short sides of the floorboards in FIG. 6c have
a locking system which only locks horizontally, the whole floor
could be installed with angling only.
[0050] FIG. 7a shows a combination floor in which one floorboard 1
has a harder surface, such as laminate, wood, linoleum, plastic
etc. than an other floorboard 2'. One floorboar 2' has in this
embodiment a softer surface layer which is positioned higher than
the harder surface layer of the other 1' floorboard. It is
preferable to position the softer surface layer on the same or
higher level than the harder surface layer. The advantage is the
the softer and more flexible layer protects the edges of the hard
surface.
[0051] FIG. 7b shows a floorboard with a soft fibre layer 32 on the
rear side which may be used as a balancing layer.
[0052] FIG. 7c shows a locking system which only locks horizontally
and FIG. 7d shows a locking system which only locks vertically.
[0053] FIG. 7e shows a floorboard where the thickness T1 of the
soft surface layer 31 is equal or larger than 0.5 times the
thickness T2 of the core. Such a thin core gives several advantages
related to production cost, transport, installation etc. It is
possible to produce a mechanical locking system by machining in a
sheet material which has a thickness of 3-5 mm only. Generally
diamond tools are used and in order to reach the best cost and
quality levels, the tools should be as thick and compact as
possible. A difficult part to produce is the groove 36. In this
embodiment the grove 36 and the tongue 38 has a vertical thickness
T3 which is larger or equal than 0.5 times the thickness T2 of the
core 30.
[0054] It is obvious that all prior-art parquet and tile patterns
can be made by means of floorboards according to the invention. The
sides of the floorboards need not be perpendicular. The soft
surface allows that also the thickness may be varied between
different floorboards. If the core is made of a moisture-proof
material, such as plastic or compact laminate, floorboards with a
fiber surface resembling synthetic grass can be provided. Such
floorboards can be laid immediately on the ground or on concrete,
and they may, for instance, constitute tees on golf courses,
balcony floors etc. During the winter, the boards can be taken up
and stored under a roof.
[0055] Although only preferred embodiments are specifically
illustrated and described herein, it will be appreciated that many
modifications and variations of the present invention are possible
in light of the above teachings and within the purview of the
appended claims without departing from the spirit and intended
scope of the invention.
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