U.S. patent application number 10/047661 was filed with the patent office on 2002-12-05 for panel for floor coverings and relative floor covering consisting of floor panels.
This patent application is currently assigned to PATT SrI. Invention is credited to Fantoni, Giovanni, Zancai, Lucio.
Application Number | 20020178681 10/047661 |
Document ID | / |
Family ID | 11395517 |
Filed Date | 2002-12-05 |
United States Patent
Application |
20020178681 |
Kind Code |
A1 |
Zancai, Lucio ; et
al. |
December 5, 2002 |
Panel for floor coverings and relative floor covering consisting of
floor panels
Abstract
Panel for floor coverings and relative floor covering consisting
of floor panels made of composite material, wherein the floor
covering comprises a plurality of panels (10) arranged adjacent to
each other and joined together two by two in correspondence with at
least two respective sides and wherein the panels include, on the
opposite longitudinal sides, first male coupling means ("C") and
first female coupling means ("D"), and, on the opposite butt sides,
second male coupling means ("E") and mating second female coupling
means ("F"). The butt end male-female coupling means ("E", "F")
have respective and mating cam-type ends (33, 36) able to cooperate
through interference in the butt-wise coupling of two adjacent
panels.
Inventors: |
Zancai, Lucio; (Cordenons
(PN), IT) ; Fantoni, Giovanni; (Gemona (UD),
IT) |
Correspondence
Address: |
AKIN, GUMP, STRAUSS, HAUER & FELD, L.L.P.
ONE COMMERCE SQUARE, SUITE 2200
2005 MARKET STREET
PHILADELPHIA
PA
19103
US
|
Assignee: |
PATT SrI
|
Family ID: |
11395517 |
Appl. No.: |
10/047661 |
Filed: |
October 22, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10047661 |
Oct 22, 2001 |
|
|
|
PCT/EP99/09390 |
Dec 1, 1999 |
|
|
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Current U.S.
Class: |
52/592.1 |
Current CPC
Class: |
E04F 15/02 20130101;
E04F 15/04 20130101; E04F 2201/0138 20130101; E04F 2201/0153
20130101; E04F 2201/01 20130101 |
Class at
Publication: |
52/592.1 |
International
Class: |
E04B 002/08; E04B
002/18; E04B 002/32; E04B 002/46 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 20, 1999 |
IT |
PN99A000038 |
Claims
1- Panel made of composite material such as MDF, HDF or impregnated
chipboard, including at least one upper face or plane (48) and a
lower face or plane (49), said panel (10) including two opposite
longitudinal sides having respective male means ("C") and female
means ("D") for the reciprocal connection of two panels (10), said
male means ("C") including at least a projecting portion (11)
extending coplanar to said upper plane (48), and said female means
("D") including at least a projecting portion (16) extending
coplanar to said lower plane (49), the panel having a thickness
("1") and a median longitudinal axis ("X"), characterized in that
said male-female means have, in reciprocal cooperation: i) said
male means ("C") a wall (112) which begins from the upper plane
(48) and is orthogonal thereto, said wall (112) terminating with a
tooth (12) protruding towards the outside for a width (40) and
substantially parallel to said upper plane (48), said tooth (12)
extending downwards for a height (50) substantially equal to the
width (40) and connecting with an underlying horizontal plane (13)
which extends towards the inside so as to define a bevel (15)
inclined by an angle (.beta.) with respect to the vertical, the
bevel (15) cooperating with a recess (14) defined by a
substantially vertical wall (314) separated from said wall (112) by
a width (43), said wall (314) connecting with a horizontal plane
(414) of a width (42) which terminates on a wall (22) which extends
as far as said lower plane (49), the width (41 =40+42+43) of said
projecting portion (11), defined between the outer end of said
tooth (12) and said wall (22), being equal to about the value of
the thickness ("l") of the panel (10); ii) said female means ("D")
a first wall (44) beginning from said upper plane (48) and having a
height (47) substantially equal to the height of said wall (112) of
the male means ("C"), said first wall (44) including a
substantially vertical first upper tract (121) and a second lower
tract (221) inclined towards the inside by an angle (.gamma.), said
second lower tract (221) extending in a horizontal recess (21)
defined by a horizontal wall (321), a vertical wall (421) and a
horizontal plane (19), said recess (21) having a length (40) and
height (50) mating with the length and height of said tooth (12) of
the male means ("C"), said horizontal plane (19) having a length
mating with that of said plane (13) of the male means ("C"), said
plane (19) extending with a groove (20) connected to a tooth (17)
comprising a substantially vertical wall (118) which connects with
a substantially horizontal upper plane (18), the upper plane (18)
connecting to said lower plane (49) with a substantially vertical
wall.
2- Panel as in claim 1, characterized in that the tooth (12) has a
length (40) equal to about 1/4 of said thickness ("l").
3- Panel as in claim 1, characterized in that between said tooth
(12) and said plane (13) there is a bevel (113) directed rearwards
and defining an angle (.alpha.) with respect to the vertical, said
angle (.alpha.) being between about 20.degree. and about
30.degree..
4- Panel as in claim 3, characterized in that said bevel (113) is
arranged substantially astride said median axis ("X") of the panel
(10).
5- Panel as in any claim hereinbefore, characterized in that the
height (52) of said plane (13) with respect to said lower plane
(49) is equal to about 1/3 of the thickness ("l") of said panel
(10).
6- Panel as in any claim hereinbefore, characterized in that the
inclination (.beta.) of said bevel (15) with respect to the
vertical is equal to about 45.degree..
7- Panel as in any claim hereinbefore, characterized in that said
wall (22) consists of a first tract (114) orthogonal to said upper
plane (48) and a second tract (214) angled rearwards with respect
to the vertical by an angle (.gamma.), said angle (.gamma.) being
equal to about half of said angle (.alpha.).
8- Panel as in any claim hereinbefore, characterized in that the
distance (42) between said wall (112) and said wall (314) is equal
to about 1/3 of the thickness ("l") of the panel (10).
9- Panel as in any claim hereinbefore, characterized in that said
upper plane (18) of the female means ("D") has a width (42) mating
with the width of said plane (414) of said male means ("C").
10- Panel as in claim 9, characterized in that said upper plane
(18) of the female means ("D") is located at a height slightly
lower than the height of the plane (414) of the male means
("C").
11- Panel as in any claim hereinbefore, characterized in that said
groove (20) is able to perform an at least partial function of
elastic hinge for the terminal end of said female means ("D") at
least during the coupling phase of two adjacent panels, when said
bevel (15) thrusts against said upper plane (18).
12- Panel as in any claim hereinbefore, characterized in that said
groove (20) has a minimum section equal to at most a quarter of the
total thickness of the panel (10).
13- Panel made of composite material such as MDF, HDF or
impregnated chipboard, including at least one upper face or plane
(48) and a lower face or plane (49), said panel (10) including a
thickness "l" and respective male means ("E") and female means
("F") for the reciprocal butt-wise connection of two panels (10),
said male means ("E") including a projecting extension (34)
extending coplanar to said upper plane (48), and said female means
("F") including a projecting extension (30) extending coplanar to
said lower plane (49), characterized in that said male-female means
("E", "F") have, in reciprocal cooperation: i) said male means
("E") a vertical wall (53) beginning from said upper plane (48) and
substantially orthogonal thereto, which is connected to a plane
(35) facing towards the inside and substantially horizontal, said
plane (35) extending terminally in an S-shaped profile lying on a
vertical plane, said S-shaped profile defining a cam-type end (36)
which extends so as to define a recess-type seat (56) the bottom of
which is displaced towards the outside of the panel (10) with
respect to the vertical plane passing through the edge of said
cam-type end (36), said recess-type seat (56) being connected to a
substantially horizontal wall (58), said wall (58) extending with a
wall (60) connecting to said lower plane (49); ii) said female
means ("F") a first wall (62) beginning from said upper plane (48)
and substantially orthogonal thereto, said wall (62) extending with
a substantially horizontal wall (31) on which at least the front
end of said plane (35) of the male means ("E") is able to rest,
said wall (31) extending in a groove (32) defining a bottom (132),
said groove (32) extending upwards so as to define an S-shaped
profile lying on a vertical plane and defined by a cam-type end
(33) the edge of which faces towards said vertical wall (62), said
cam-type end (33) of said female means ("F") being able to
cooperate through interference, during the coupling phase of two
panels (10), with the mating cam-type end (36) of the male means
("E") and to be at least partly housed in said recess-type seat
(56), said cam-type end (33) extending in a substantially
horizontal wall (63) of a width (64) mating with the width of said
wall (58) of said male means ("E"), said wall (63) being connected
to said lower plane (49) by means of a substantially vertical wall
(65).
14- Panel as in claim 13, characterized in that said vertical wall
(53) has a height (54) equal to at least half the thickness ("l")
of said panel (10).
15- Panel as in claim 13 or 14, characterized in that said wall
(60) has a first tract (160) substantially orthogonal to said lower
plane (49) and a second tract (260) inclined rearwards by an angle
(.alpha.1).
16- Panel as in any claim from 13 to 15 inclusive, characterized in
that the distance (59) between said wall (58) and said lower plane
(49) is at least equal to half the thickness ("l") of said panel
(10).
17- Panel as in any claim from 13 to 16 inclusive, characterized in
that said wall (31) has a first tract (131) and a second tract
(231) joined by a bevel (331) inclined downwards, so that said
second tract (231) is sunken with respect to said first tract
(131).
18- Panel as in any claim from 13 to 17 inclusive, characterized in
that the bottom (132) of said groove (32) is connected and sunken
with respect to said wall (31).
19- Floor covering formed by panels made of composite material,
comprising a plurality of panels (10) arranged adjacent to each
other and joined two by two in correspondence with at least two
respective sides, characterized in that, on a first pair of
opposite longitudinal sides, said panels have first male coupling
means ("C") and first female coupling means ("D"), and, on the
opposite butt sides, second male coupling means ("E") and mating
second female coupling means ("F"), the coupling of two adjacent
panels being obtained by coupling said first male coupling means
("C") of one panel (10) to said first female coupling means ("D")
of an adjacent panel (10), then by taking into contact the butt
edges (37, 38) of said two panels (10), and then by rotating one
panel (10) to be positioned with respect to an already positioned
panel (10) in a scissor-like manner from up to down, in order to
couple, through interference, one cam-type end (36) of said second
male coupling means ("E") of one panel (10) included in
correspondence with the butt side with a mating cam-type end (33)
of said second female coupling means ("F") of the adjacent panel
(10).
Description
[0001] The present invention refers to a floor covering formed by
panels constituted by boards of cellulose fibers or wood shavings
bound with synthetic resins, generally known in the art as MDF
(Medium Density Fiberboards), HDF (High Density Fiberboards) and
faced chipboards.
[0002] Floor coverings of the above cited kind have been known for
a long time now, while a number of different solutions have been
proposed to keep the panels joined to each other.
[0003] In a first example, the edges of the panels are profiled so
as to bring about tongue-and-groove joints between contiguous
panels. In order to prevent assembled panels from possibly
separating from each other, thereby creating unwanted gaps or
clearances, additional measures are quite often taken such as
glueing the edges or using metal or plastic interconnecting
profiles.
[0004] In an improved example, the edges of the panels have
profiles that are so shaped as to feature snap-fit joining
elements, in such a manner as to do away with the need for
additional components or materials to be used for strengthening the
joints. This solution, which is described in WO 94/1628, WO
96/27719 and WO 96/27721, is however not effective in ensuring an
adequate and firm stability along all sides of the panels.
[0005] Of these, WO 96/27719 provides a coupling of the long sides
of two contiguous panels achieved by two pairs of mating teeth with
plane surfaces, parallel and orthogonal to each other.
[0006] A first panel has a first front tooth, with plane and
parallel surfaces, suitable to be inserted through rotation and
sliding into a recess with plane and parallel surfaces made inside
the second panel; in a terminal position and on the lower face, the
second panel has a compartment comprising a tooth facing towards
the base which is inserted in an inner recess made on the extension
of the base of the first panel and in an intermediate position of a
ridge cooperating with the compartment.
[0007] This type of coupling causes a rigid constraint, forced and
without play between the panels, which are not therefore able to
slide longitudinally and freely with respect to each other once
they have been assembled. Moreover, the coupling is not able to
compensate production tolerances and/or deformations of the
material with the passing of time, and is not able to allow
reciprocal lateral movements of adjustment. Furthermore, to achieve
such a coupling it is necessary to provide at least three different
types of material, with obvious problems of reciprocal attachment
and different shrinkage.
[0008] When the floor covering has been laid, it is extremely
difficult to separate the panels from each other, so that every
intervention of maintenance and repair entails risks of breakage
and damage.
[0009] Moreover, this document does not describe how the butt-wise
coupling of two adjacent panels is achieved.
[0010] Document EP-A-698162 provides a coupling through rotation
and sliding similar to that described in WO'719, but without the
tooth and mating inner recess. In this case too, at least two
different types of material are necessary, with problems of
reciprocal anchorage and problems of different shrinkage.
[0011] In EP'162 the coupling of two panels is achieved so as to
maintain a certain play orthogonal to the axis of the coupling, so
that, even after assembly, the panels are free to slide
longitudinally with respect to each other and to move laterally,
using the free spaces.
[0012] However, the solution shown in EP'162 has the disadvantage
that no component of the coupling can be elastically deformed, not
even temporarily.
[0013] Moreover, the section of the panel in the coupling zones
does not have any undercut or bevel which can facilitate the
insertion through rotation.
[0014] This leads to the disadvantage that, in order to be able to
insert the front tooth of the first panel into the recess of the
second panel, simultaneously taking the compartment to couple with
the mating recess, it is necessary to provide a great projecting
length of the lateral zones of the panels on which the respective
coupling elements are made.
[0015] Given the very limited thickness of the panel, the size of
the projecting teeth present on the sides of the panels cannot be
reduced to less than a minimum value, both because of problems of
mechanical resistance, and also because of geometric problems of
rotation and insertion. A great width of the lateral projecting
zones, where the panels are coupled together, entails, in the first
place, a constraint of minimum width of the panel below which it is
not possible to go.
[0016] Moreover, it entails a greater fragility and risks of
breakage of the projecting parts, which are thinner compared with
the overall thickness of the panel.
[0017] This is even more true when we consider that the tendency at
present is to try to obtain the panels in a composite material
based on pressed wood shavings (for example with a product known
commercially as MDF or HDF).
[0018] Furthermore, it entails bands of structural weakening of the
panels in correspondence with the coupling zones, which are
characterized by a much lower capacity to resist localized loads
applied to the floor covering.
[0019] To overcome this problem, EP'162 provides an auxiliary
element of metal reinforcement to support the floor covering, but
this creates problems in the processing, problems of costs, of
coupling of the materials and of laying.
[0020] In this document too, there is no mention of the procedure
to couple the butt sides of the panels.
[0021] A solution has been proposed (WO 97/47834) in which the
edges of the panels are provided with mutually engaging elements in
the form of tongues and grooves, which are provided with mechanical
locking means adapted to prevent the edges from possibly separating
from each other. These locking means are provided integrally with
the related panel and the coupling is brought about laterally along
the edges by just snap-fitting and/or rotating them into fastening.
The locking means are represented by inclined-plane profiles that
are forced elastically into coupling. The preferred inclination of
the coupling surfaces is indicated to lie anywhere between
30.degree. and 70.degree. with respect to the horizontal plane. The
contours of the edges of such panels appear to be rather complex,
since the aim is to obtain the coupling along the longitudinal
edges through a rotary movement and subsequent snap-fit engagement,
while the butt joints are obtained directly by snap-fitting,
preferably with the use of tools. In substance, it therefore ensues
that, when the panels are so assembled, the locking means exert a
tension that forces contiguous panels against each other.
[0022] Such a solution as disclosed in WO 97/47834 has a number of
drawbacks. In the first place, since the coupling of the panels
with each other is forced by means of a mechanical tension, the
need arises for very solid, strong materials to be used in the
construction of said panels, such as in particular high-density
compressed fiberboards (HDF), to be further specially reinforced
along their edges.
[0023] Moreover, such a forced fitting brings about a certain
extent of downward bending of the tongues of the panels that remain
or are put under load. This has a twofold negative consequence, ie.
(i) the need for an elastic support layer to be always provided
under the floor covering in order to dimensionally absorb the
deflection of the tongues in view of preventing them from breaking,
and (ii) a constant possibility of fracture due to the strain to
which the tongues are submitted along a horizontal plane in a
central section of the panel in correspondence with the bottom of
the groove. Such a possibility of the panels breaking along a
central portion thereof arises still more easily when the panels
are butt joined, ie. when use must be made of a wall abuttal wedge
or a wooden block, driven with an appropriate tool such as a
hammer, in order to bring about the forced coupling. Of course,
owing to the surface tensioning of the panels due to the melamine
layers of the surfaces, any rupture within the same panels would
unfailingly cause the edge thereof to raise with respect to the
plane of the floor, with negative consequences not only from an
aesthetical point of view, but also in connection with arising
risks of stumbling and the weardown of the upper surface of the so
exposed edge. Finally, a floor covering in which the panels are
kept joined to each other by forced snap-fit coupling and under
constant tension, cannot be disassembled to modification or repair
purposes without incurring the risk of seriously damaging it.
[0024] It therefore is a main purpose of the present invention to
provide a floor covering made of MDF, HDF or faced-chipboard panels
which is simpler as far as both the construction of the panels and
the assembly thereof are concerned, wherein the coupling and
attachment means are obtained directly from the material of the
panel without other additional materials, which has tensionless
coupling means that enable the same panels to slide both
longitudinally and along their butt joints relative to each other.
Such sliding not only facilitates the assembly and disassembly, it
also allows the floor covering to be laid without difficulty.
[0025] Another purpose of the invention is to reduce the width of
the projecting coupling parts, reducing the risks of unwanted
deflection and breakage, and also the amplitude of fragile zones
subject to deformation when there are localized loads.
[0026] The attachment means are embodied in a partly elastic front
element which temporarily bends during the insertion and rotation
of two adjacent panels, thus facilitating the laying operations,
the coupling of the panels and, also, possible later operations to
disassemble them.
[0027] When the operation to couple one panel with the contiguous
one has been completed, and when the panels are in a coplaner
position, the elastic flection of the material is released, so that
the two panels are coupled without any reciprocal tension.
[0028] Thanks to the geometry of the attachment means, this
solution allows to keep free spaces between the coupling surfaces,
in order to allow two adjacent panels to slide freely in
longitudinal manner, and also to make lateral movements of
adjustment to recover play, tolerances and deformations of the
material.
[0029] On two opposite longitudinal sides, each panel has first
male attachment means and mating first female attachment means,
which comprise projecting portions with a width substantially equal
to the thickness of the panel.
[0030] The first male attachment means have a tooth protruding
towards the outside and lying on a substantially horizontal plane,
and the first female attachment means have a substantially
horizontal mating recess; the height and width of the protruding
tooth are substantially equal, that is, about 1/4 of the thickness
of the panel.
[0031] The first male attachment means and/or the first female
attachment means have bevels and/or undercuts on the vertical plane
which facilitate the insertion through rotation of two adjacent
panels during the coupling phase, allowing to further reduce the
width of the projecting portions.
[0032] The floor covering according to the present invention
therefore allows for materials without any particular solidity
characteristics to be used in manufacturing said panels, as well as
for the use of any kind of tools whatsoever to be done away when
assembling and disassembling the same floor covering. From a
functional point of view, it is then important to notice that the
panels are provided with an appropriately profiled edge, so that
any breaking or rupture that might possibly occur in use, would
develop at the base thereof, and along a vertical section, so as to
avoid any projection or prominence of the edge with respect to the
plane of the floor, and the related loss of planarity.
[0033] These and further aims are reached in a floor covering
according to the present invention which is characterized according
to what is set forth in the main claim.
[0034] The floor covering according to the invention has the
corresponding longitudinal edges of two contiguous panels which are
associated with each other by overlapping and engage each other
without any interference along at least a vertical plane, so as to
bring about a self-levelling and self-stabilizing connection under
load, with the possibility for the edges to longitudinally slide
relative to each other, and with the effect of a slight reciprocal
elastic attraction, during the coupling phase, between one panel
and the other.
[0035] The self-levelling and self-stabilizing effect is obtained
thanks to the geometric constraint created between the respective
first male-female attachment means and thanks to the planarity of
the surfaces of reciprocal coupling, which are parallel to each
other and parallel to the surface on which the floor covering
rests.
[0036] In correspondence with the butt sides of the respective
panels, the floor covering according to the invention has second
male coupling means on one side and second female coupling means on
the opposite side, able to be taken into a position of reciprocal
constraint by means of a movement of scissor-like rotation of the
new panel with respect to the one already in position.
[0037] Said coupling means of the butt sides have at least a partly
elastic element which can partly bend during the assembly of two
adjacent panels, and is released when coupling is complete; in the
coupling zones between the butt sides free spaces are formed
between reciprocally cooperating surfaces.
[0038] At least some of the second male and female coupling means
of the butt sides, according to a characteristic of the invention,
are defined by rounded cam-type profiles reciprocally mating and
coupling in forced manner, thus achieving an interference on the
vertical plane which, when the panels are in the coplaner position,
prevents movements of reciprocal lifting of two coupled panels.
[0039] Anyway, features and advantages of the present invention
will be more readily and clearly understood from the description
that is given below by way of non-limiting example with reference
to the accompanying drawings, in which:
[0040] FIG. 1 is an interrupted cross-sectional view of a panel
according to the present invention;
[0041] FIG. 2 is a partial cross-sectional view of the longitudinal
edges of two panels in the phase in which the respective side
profiles engage each other;
[0042] FIG. 3 is a partial cross-sectional view of the longitudinal
edges of the two panels of FIG. 2 in their fully engaged
condition;
[0043] FIGS. 4 to 6 are partial cross-sectional views of the
longitudinal edges of the two panels of FIG. 3 under different load
conditions;
[0044] FIG. 7 is an interrupted longitudinal sectional view of the
panel of FIG. 1;
[0045] FIG. 8 is a partial cross-sectional view of the butt sides
of two contiguous panels with their respective profiles fully
engaging each other; and
[0046] FIG. 9 is a partial perspective view of a floor covering in
the phase in which the butt profiles of the panels are
assembled.
[0047] The present invention refers to a floor covering formed by
panels of such a material as MDF, HDF or faced-chipboard, ie.
manufactured out of board made of fibers or wooden chips
impregnated with synthetic resins and faced on their surfaces with
either natural or synthetic materials.
[0048] These panels may have different shapes and dimensions, but
they are usually rectangular and are joined with each other along
all of their perimetral edges.
[0049] According to the present invention, a panel 10 (FIG. 1) has
an upper plane 48 and a lower plane 49 defining a thickness "l" and
a median axis "x", and has, on two opposite sides thereof, a
section with conjugate profiles, respectively male section "C" and
female section "D", so that two contiguous panels will then be able
to join with each other along engagement surfaces that are
orthogonal with respect to each other.
[0050] In fact, on one side, or male section "C", the
cross-sectional profile of the panel 10 can be noticed to include a
projecting portion 11 which has a reduced height with respect to
the overall height of the panel and extends horizontally along the
same plane as the upper plane of the panel.
[0051] This portion 11 further extends downwards with a vertical
wall 112, thereby forming a laterally protruding rib or tooth 12
which, in a preferred manner, is interrupted at one or more points,
ie. along one or more tracts, along its overall extension. The
tooth 12, which has a length 40 equal to about 1/4 of the thickness
"l" of the panel 10, has a plane upper surface parallel to the
upper plane 48 of the panel 10.
[0052] Moreover, the portion 11 has on its lower side a plane
horizontal surface 13 and, extending towards the inside of the
panel 10, a substantially vertical recess 14, defined by a vertical
wall 314 and by a bottom 414 which is also plane and substantially
horizontal, parallel to the upper plane 48 of the panel.
[0053] The height 52 of the plane 13 with respect to the lower
plane 49 of the panel 10 is equal to about 1/3 of the thickness "l"
of the panel 10, and this conditions to said value the thickness of
he resistant projecting section of the female section "D", as will
be described in detail hereafter.
[0054] The tooth 12 and the plane 13 are connected by means of a
bevel 113 directed rearwards and defining an angle ".alpha." with
respect to the vertical. In a preferential embodiment, said angle
".alpha." is between about 20.degree. and about 30.degree..
[0055] The tooth 12 has a height 50 substantially equal to its
width 40 and therefore it too is equal to about 1/4 of the
thickness "l" of the panel 10.
[0056] The bevel 113 is located astride the median axis "X" of the
panel 10 and is substantially symmetrical with respect thereto; the
bevel 113 encourages the reduction in the width 41 of the
projecting portion 11, and consequently of the mating projecting
portion 16 of the female section "D", since it allows, during the
insertion phase through rotation, to bring into greater reciprocal
proximity the two panels 10 which are to be coupled.
[0057] The plane 13 extends, in the solution shown here, in a bevel
15 facing upwards and defining an angle .beta. of about 45.degree.
with respect to the vertical; this bevel 15 connects to the bottom
414 of the recess 14 by means of a vertical wall 314.
[0058] The bevel 15 also encourages the reduction in the width of
the coupling zone since it thrusts, in the way which will be seen
later, upon on the elastic terminal part of the female section "D",
making it bend at least temporarily.
[0059] The vertical wall 314 is separated from the wall 112 by a
value 43, while the recess 14 has a width 42 equal to about 1/3 of
the thickness "l"; the projecting portion 11 has an overall width
41, defined by the sum of the widths 40, 42 and 43, equal to a
value which is about equal to the thickness "l" of the panel
10.
[0060] The recess 14 also has a wall 22 connecting to the lower
plane 49 which, in this case, is made in two tracts, respectively a
first, substantially vertical upper tract 114 and a second lower
tract 214, inclined towards the inside of the panel 10 and defining
an angle .gamma. with respect to the vertical. The value of the
angle .gamma. is equal to about half of the angle .alpha.. The
other, ie. opposite side, or female section "D", of the panel 10
has in turn a projecting portion 16 which has again a reduced
height with respect to the overall height of the panel and extends
horizontally along the same plane as the lower surface 49 of the
panel. The portion 16 further extends upwards with a vertical tooth
17 which extends all along the side of the panel and whose upper
surface 18 is substantially horizontal.
[0061] The upper surface 18 has a width 42 which is substantially
equal to the width of the recess 14 and is therefore equal to about
1/3 of the thickness "l" of the panel 10.
[0062] The projecting portion 16 has furthermore, going towards the
inside of the panel 10, a horizontal plane surface 19 at a lower
level than the level of the surface 18 and connected to the latter
through a vertical groove 20 opening upwards and extending in a
vertical wall 118. At the end portion of the surface 19 on the
opposite side of the groove 20, the side of the panel is provided
with a substantially horizontal recess 21.
[0063] The recess 21 is defined not only by the plane 19, but also
by a vertical wall 421 and by a horizontal wall 321 which are
mating in size with that of the tooth 12.
[0064] The recess 21 is connected to the upper plane 48 by means of
a wall 44 which, in this case, consists of a lower tract 221
inclined with respect to the vertical by an angle ".gamma." and by
a vertical upper tract 121, connected to said upper plane 48.
[0065] A particular importance, as this will be more clearly
explained further on, has to be attributed to the groove 20, which
is deeply hollowed out, ie. sunken so that the thickness of the
panel, as seen across the vertical section thereof, turns out to be
considerably reduced with respect to the overall thickness of the
panel itself.
[0066] The groove 20 also forms a hinge element which, as can be
understood from FIG. 2, allows a partial elastic flection forwards
of the terminal end of the female section "D" when the front tooth
12 of the new panel 10 is inserted into the recess 21 of the
already positioned panel 10.
[0067] When the insertion and coupling of the panels 10 has been
completed, and when the panel to be inserted has been taken to a
position coplaner with the panel already inserted, the elastic
flection of the tooth 17 is released and the two panels 10 are
coupled without being under tension.
[0068] The groove 20 also forms a balanced union joint specially
adapted to lead towards the floor, underneath the neutral axis of
the panel, the strains induced by expansions which the panel itself
may undergo in use, thereby maintaining the coplanarity of the
treading surface. The minimum section of the panel under the groove
20 shall at most be equal to one fourth of the overall thickness of
the panel.
[0069] FIG. 2 is a partial cross-sectional view of the longitudinal
sides of two panels 10 in the phase in which the respective
profiles thereof are mutually engaging.
[0070] As can be seen, the panel that has to be inserted (the one
shown on the right side of the Figure) is drawn in an inclined
position alongside the already arranged matching panel, while the
insertion is made by simply rotating the edge portion 11 of the
panel to be inserted with respect to the edge portion 16 of the
matching panel already arranged in position.
[0071] The tooth 12 and the corresponding accommodating seat 21
hereby form the fulcrum about which the rotary motion for
assembling and disassembling the panels is performed, whereas the
action of thrust caused by the bevel 15 on the plane wall 18
determines the elastic flection forwards of the end of the female
section "D" which allows to introduce the tooth 12 into the recess
21 even when there is a limited rotation space.
[0072] The upper resting plane between the tooth 12 and its seat 21
is horizontal and positioned very close to or coinciding with the
neutral axis of the cross-section of the panel. The insertion is
facilitated not only by the elastic flexibility of the tooth 17,
but also, as said, by the fact that the vertical engagement
profiles, that is to say, the walls 22 and 44, of the two panels
are "relieved", ie. slightly beveled in order to prevent them from
mutually interfering when they are coupled together and enter into
contact with each other.
[0073] The insertion of the front tooth 12 inside the recess 21,
and the simultaneous insertion of the raised tooth 17 into the seat
14, are facilitated by the fact that the reciprocal sizes of teeth
and recesses allow to maintain a certain coupling play, that is to
say, the coupling does not occur with the shapes coinciding, but
free spaces remain which allow a reciprocal movement without
friction and rubbing.
[0074] FIG. 3 is a partial cross-sectional view of the detail shown
in FIG. 2, however in the phase in which the engagement, ie.
coupling between the two contiguous panels has been completed. It
should be noticed that, when coupling is terminated, the panels
turn out to be simply resting on each other along a horizontal
plane on which the lower surface 13 of the portion 11 of a panel
(ie. the one shown in the left side of the Figure) and the upper
surface 19 of the portion 16 of the other panel (ie. the one shown
on the right side of the Figure) come to meet with each other.
[0075] The tooth 12 engages the recess 21, and the tooth 17 in turn
engages the recess 14, in a loose manner since they only serve a
locating and retaining purpose when positioning and assembling the
panels. Since the edges of the panels are not joined to each other
by any kind of forced coupling, but taking merely advantage of the
elasticity of the materials, it clearly emerges that two contiguous
panels are in this manner capable of freely sliding with respect to
each other, thereby facilitating the assembly as well as the butt
joining of contiguous panels.
[0076] As the afore cited FIG. 3, FIGS. 4 to 6 illustrate the
detail of the longitudinal coupling of two panels with each other
under differing conditions of load applied to the floor.
[0077] In particular, FIG. 4 illustrates the case in which a force
F, applied to the upper end portion of the panel on the right side
of the Figure, triggers a reaction R of the slab under the floor,
wherein said reaction is transmitted through the mutual contact
surfaces along the path indicated by the arrows inside the panels.
In a fully similar manner can be noticed to behave the two so
engaged when the force F is applied on to the upper end portion of
the panel on the left-hand side in FIG. 5. Finally, when both upper
end portions of the two panels are loaded with a force F, as shown
in FIG. 6, the reaction R of the slab under the floor is
transmitted inside the panels where it balances at the vertical
contact surfaces.
[0078] FIG. 7 is an interrupted longitudinal-section view of the
panel illustrated in FIG. 1, while FIG. 8 is a partial sectional
view of the butt sides of two contiguous panels 10 with the
respective profiles in a fully engaged condition. A panel (ie. the
one on the left-hand side of the Figure) is provided with a female
element "F" comprising a projecting extension 30, which is aligned
with the lower surface 49 of the same panel and whose profile, when
seen across its section, includes a vertical wall 65, a horizontal
wall 63 with a width 64, a substantially horizontal resting and
reference plane 31, as well as a groove 32, defining a bottom 132
which follows a sunken contour with respect to, ie. is lower than
the plane 31, and a cam-shaped end portion 33 and a vertical wall
62.
[0079] The sunken groove 32 extends upwards, connecting with the
horizontal wall 63, so as to define an S-shaped profile lying on a
vertical plane and defined by a cam-type end 33 the edge of which
faces towards the inside of the panel 10. The sunken groove 32 also
performs the function of a hinge element to allow a partial elastic
flection of the cam-type end 33 during the coupling phase of two
contiguous panels.
[0080] Correspondingly, the other panel (ie. the one on the
right-hand side of the Figure) has a male element "E" comprising a
projecting extension 34 aligned with the upper surface 48 of the
same panel, whose profile features a vertical wall 53, a
substantially horizontal resting and reference plane 35 which
extends upwards in an S-shaped profile lying on a vertical plane
and defining a cam-shaped appendix 36, mating with the cam-type end
33 on the other side. The cam-type end 36 then extends into a
recessed seat 56, displaced towards the outside and connected to a
horizontal wall 58, which is connected to the lower plane by means
of a substantially vertical wall 60.
[0081] The planes 31 and 35 can be noticed to be mutually coupled
by simply resting on each other when the two panels are assembled,
while the cam-type end portions 33 and 36 engage each other with
interference on a vertical plane, so as to prevent reciprocal
movements between the two panels 10 when they are engaged with each
other (FIG. 8).
[0082] In the solution shown here, the wall 60 comprises a
substantially vertical first tract 160 and a second tract 260
inclined towards the inside by an angle of .gamma.1.
[0083] Moreover, the plane 31 has a first tract 131 and a second
tract 231 connected to each other by a bevel 331 inclined
downwards, so that said second tract 231 is sunken with respect to
the first tract 131.
[0084] FIG. 9 is a partial perspective view the positioning phase
for the butt assembly of the panels of FIG. 8. This assembly is
facilitated by the fact that, as we have seen above, the panels 10
can be made to slide longitudinally with respect to each other,
without friction and rubbing, even when they are already coupled
together with the respective long sides.
[0085] As it can be seen, the assembly is carried out by bringing
the longitudinal edge of a panel 10 to rest, according to the arrow
A, on the corresponding edges of the contiguous panels, while
bringing the butt edges 37 and 38 of the panels to be assembled
into mutual contact. Then, the panel 10 is rotated according to the
arrow B, while causing, with a scissor-like motion according to a
vertical plane, the edge 37 to close against the edge 38, until the
panel 10 is fully coplanar with the contiguous panels.
[0086] During the rotation and coupling phase, the cam-type
appendix 36 of the panel 10 to be inserted exerts on the mating
cam-type end 33 a thrust which determines a partial elastic
flection forwards of said end 33.
[0087] When the two panels 10 have reached a position of
coplanarity, the elastic flection of the cam-type end 33 is
released, so that, even in correspondence with the respective butt
ends, the two panels 10 are coupled without tensioning. Moreover,
the undercuts consisting of the inclined bevel 331 and the inclined
tract 260 determine a coupling with play, which prevents tensioning
between two coupled panels 10.
[0088] The respective projecting extensions, male 34 and female 30,
have respective heights 54 and 59 equal to at least half of the
thickness "l" of the panel 10, so as to ensure a sufficient
mechanical resistance which prevents unwanted breakages and
flections.
[0089] It clearly emerges that all panels have the same form, with
two adjacent edges having a "male" profile and the other two
adjacent edges having a "female" profile, as shown in FIGS. 1 and
7. From the same Figures it can be further noticed that contiguous
panels are coupled by both mutual support 13, 19 and 31, 35 and
double-hook coupling 14, 17 and 33, 36, respectively, however
without being in a tension state. It is also clear that the
presence of the grooves 20 and 32, which function as hinge elements
respectively for the raised tooth 17 and the end 33, allows to
achieve easy couplings, side-wise and butt-wise, thus reducing to a
minimum the width of the face intended for coupling.
[0090] Both the assembly and the disassembly of the panels are
thereby facilitated, without any need for tools of any kind to be
used, along with the adaptation to possible settlings of the plane
on which the flooring rests.
[0091] As a result, the floor covering according to the present
invention, as obtained by assembling panels having the afore
described profile and coupled together by simply rotating and
laying them down to rest on each other, without any forced
engagement of the edges, is self-levelling and self-stabilizing
under load conditions.
[0092] In prior-art floor coverings, and particularly in floor
coverings of the kind described in WO 97/47834, possible breakages,
due to coupling edges being put under tension both during assembly
and in practical use, occur inside the body of the panel and tend
to develop in a horizontal direction, with the practical result of
the edges of the panels becoming exposed both at the lower surface
and the upper surface thereof. While such an edge exposure at the
lower surface is generally not critical in itself, since it is
absorbed by the layer of elastic material arranged between the
flooring and the slab therebeneath, the upper edge exposure is on
the contrary very annoying, since it causes people to stumble and
the flooring itself to incur damages.
[0093] These drawbacks are done away with in the floor covering
according to the present invention, as it can be easily inferred
from the above description and the accompanying Figures. The
advantage derives mainly from the non-forced coupling along the
horizontal plane of the panels. Furthermore, in correspondence of
the grooves 20 and 32 in the lower extension portions 16 and 30 of
each panel 10, zones are formed which have a lower strength than
the main panel body owing to the reduced cross-section size.
Therefore, even in the case that a panel eventually suffers an
accidental breakage, the latter would occur in correspondence of
the groove 20 and/or the groove 32 and would further develop in a
vertical direction without involving the central portion of the
panel.
[0094] As a result, the resulting damage would only be limited in
its extent and would not be transferred on to the upper surface of
the panel.
* * * * *