Floor covering consisting of hard panels

The present invention concerns a floor covering, in particular of the type consisting of hard panels.

In particular, it concerns a floor covering formed of laminate panels, also called laminate parquet.

It is known that such laminate panels can be made of different layers. Usually, the panels are formed of boards on the basis of wood, such as chipboard or fiberboard, in particular MDF or HDF, upon which one or several layers, including a decorative layer, are provided at least on the top side. The decorative layer may be a printed paper layer, but in certain embodiments it may just as well be a layer of wood, in particular veneer. Such panels can also be made of other materials, for example merely synthetic material, or of a base plate on the basis of wood, such as chipboard, MDF or HDF and the like, upon which is provided, instead of a printed paper layer or veneer, another material such as cork, thin strips of wood and the like.

It is also known to couple these panels on their edges as they are laid, either by means of a conventional tongue and groove joint, whereby they are possibly glued together, either by means of a glueless coupling which provides for a mutual interlocking of the panels both in the horizontal and vertical direction, for example as described in international patent No. <patcit id="pcit0001" dnum="WO9747834A"><text>97/47834</text></patcit>.

Further customary panels are disclosed in <patcit id="pcit0002" dnum="US4426820A"><text>US 4 426 820</text></patcit>, in particular in <figref idref="f0007 f0008">fig. 18-20</figref>.

The present invention, as defined in claim 1, aims at a floor covering of hard panels, in particular laminate panels, which provides for new embodiments offering respective advantages ; furthermore, the present invention is according to claim 14 related to a hard panel for making a floor covering.

The claimed invention is as defined in the appended claims. A first aspect, to which the invention relates, provides for a floor covering consisting of hard panels, whereby these panels are provided, at least on two opposite edges, with coupling means made in one piece with the panels, so that several of such panels can be mutually coupled, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned and parallel to the plane of the floor covering, whereby said coupling means comprise a tongue and a groove and whereby the lip which is situated on the bottom side of the groove, hereafter called the lower lip, is longer than the lip on the top side, hereafter called the upper lip, and whereby the edge which is provided with the tongue, is made flexible.

As the edge onto which the tongue is provided is flexible, deflections arising during the coupling of the panels are absorbed by this edge, and the above-mentioned upper lip is safeguarded against large deflections, as a result of which the material cannot possibly split due to the bending of the lower lip.

The lower lip is preferably even made rigid, by making it sufficiently thick, so that any bending in this lip is entirely excluded.

According to a possibility, the above-mentioned flexibility is obtained by making at least the tongue flexible. According to the invention, which is preferably combined with the aforementioned possibility, and which contributes even more to the required flexibility being obtained, the tongue is situated on a part which is connected to the actual panel via a flexible zone in the shape of a local constriction.

Specific advantages of the embodiment according to the first aspect are further explained in the following detailed description.

The coupling means are preferably made such that they allow the panels to be coupled by pushing them laterally towards one another.

A second aspect, which is a non-claimed embodiment, provides for a floor covering consisting of hard panels, whereby these panels are provided with coupling means on at least two opposite edges, as a result of which several of such panels can be mutually coupled to one another, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned, and parallel to the plane of the floor covering, whereby said coupling means comprise a tongue and a groove and whereby the lip situated on the bottom side of the groove, hereafter called the lower lip, is longer than the lip on the top side, hereafter called the upper lip, characterized in that the coupling means consist at least of first coupling parts, formed of contact surfaces working in conjunction with one another, on the top side of the tongue and the bottom side of the upper lip respectively; second coupling parts formed of contact surfaces, on the top side of the lower lip and an opposite part of the other panel respectively; and third coupling parts providing for the horizontal interlocking, which are situated on the lower lip, yet further than the free end of the upper lip, whereby these third coupling parts are situated between the first and second ones.

As a result, the vertical forces which are created when walking over the floor covering, are divided over two places, which results in a better distribution of the forces.

The third coupling parts preferably consist of an inwardly directed contact surface provided near the free end of the lower lip, on this lip, and a contact surface working in conjunction with it which is formed on the other panel.

The second coupling parts preferably consist of a contact surface formed on the top side of the free end of the lower lip, as well as a contact surface working in conjunction with it on the bottom side of the other panel.

Moreover, a free space is preferably provided under the tongue extending as of the tip of the tongue up to the third coupling parts. As a result, the tongue can be put more easily in the groove, without having to take very precise tolerances into account.

A third aspect, which is a non-claimed embodiment, provides for a floor covering consisting of hard panels, whereby these panels are provided with coupling means on at least two opposite edges, so that several of such panels can be mutually coupled, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned and parallel to the plane of the floor covering, whereby said coupling means comprise a tongue and a groove and whereby the lip which is situated on the bottom side of the groove, hereafter called the lower lip, is longer than the lip on the top side, hereafter called the upper lip, characterized in that the coupling means consist at least of first coupling parts formed of contact surfaces working in conjunction with one another, on the top side of the tongue and the bottom side of the upper lip respectively; second coupling parts formed of contact surfaces, on the top side of the lower lip and an opposite part of the other panel respectively; and third coupling parts which provide for the horizontal interlocking situated on the lower lip, yet further than the free end of the upper lip, whereby the second coupling parts are situated between the first and the third ones, and whereby these second coupling parts consist of contact surfaces working in conjunction with one another and defining a local contact zone situated in the middle or practically in the middle between the tip of the tongue and the third coupling parts.

By making use of such a local contact zone, there remains a space between this zone and the tip of the tongue, on the bottom side of the latter, which makes sure that there is freedom of movement for the tongue when the panels are joined.

A fourth aspect, not belonging to the invention, provides for a floor covering consisting of hard panels, whereby these panels are provided with coupling means on at least two opposite edges made in one piece with the panels, as a result of which several of such panels can be mutually coupled to one another, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned, and parallel to the plane of the floor covering, whereby said coupling means comprise a tongue and a groove, characterized in that the lip situated on the top side of the groove, hereafter called the upper lip, is longer than the lip situated on the bottom side of the groove, hereafter called the lower lip, and in that the above-mentioned coupling means contain coupling parts which provide for the interlocking in the horizontal direction, whereby these coupling parts consist at least of contact surfaces working in conjunction with one another, provided on the bottom side of the upper lip, outside the distal end of the lower lip, and on the opposite part of the edge of the other panel respectively.

As the interlocking takes place on the upper lip, it is easier to check the reliability of the interlocking while the floor is being laid than in the case where the interlocking takes place on the lower lip.

A fifth aspect, not belonging to the invention, provides for a floor covering consisting of hard panels, whereby these panels are provided with coupling means on at least two opposite edges made in one piece with the panels, as a result of which several of such panels can be mutually coupled to one another, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned, and parallel to the plane of the floor covering, whereby said coupling means comprise a tongue and a groove, characterized in that the lip situated on the top side of the groove, hereafter called the upper lip, is longer than the lip situated on the bottom side of the groove, hereafter called the lower lip, and in that the above-mentioned coupling means contain coupling parts which provide for the interlocking in the horizontal direction, whereby these coupling parts make it possible for these panels to be mutually disconnected by turning them down with their bottom side and towards one another.

Thanks to the use of coupling means which make it possible for the panels to be disconnected by turning them downward, and preferably to be exclusively disconnectable by this movement, is obtained that such panels fit particularly tight on the coupling means concerned, and are pushed even closer towards one another when being walked on.

The panels are hereby preferably rectangular, and they are provided with coupling means on two pairs of edges which make it possible for the panels to be disconnected by means of an upward rotation in order to be unlocked, whereas, on the other pair of edges, as mentioned above, they are provided with coupling means which only allow for a disconnection by turning the coupled panels with their bottom side towards one another. Also the opposite turning movements increase the guarantee that such a coupling remains always available.

It should be noted that in the case of longitudinal panels, the coupling means which allow for a disconnection by turning the panels upward are preferably provided on the longitudinal sides, whereas the coupling means which allow for a disconnection by turning the panels down, are preferably provided on the shortest sides.

A sixth aspect, which is a non-claimed embodiment, provides for a floor covering consisting of hard panels, whereby these panels are provided with coupling means on at least two opposite edges made in one piece with the panels, as a result of which several of such panels can be mutually coupled to one another, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned, and parallel to the plane of the floor covering, whereby said coupling means comprise a tongue and a groove, characterized in that the interlocking in the horizontal direction is at least formed of coupling parts in the shape of a local protrusion in the top side of the above-mentioned tongue, which meshes in a recess in the lip which borders the top side of the groove.

An advantage of this embodiment consists in that, since the protrusion is local, the recess can also have relatively small dimensions, and the upper lip is only weakened locally.

According to the sixth aspect, there is preferably no interlocking in the horizontal direction on the lower lip.

A seventh aspect, which is a non-claimed embodiment, provides for a floor covering consisting of hard panels, whereby these panels are provided with coupling means on at least two opposite edges made in one piece with the panels, as a result of which several of such panels can be mutually coupled to one another, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned, and parallel to the plane of the floor covering, and whereby: <ul id="ul0001" list-style="dash" compact="compact"><li>the above-mentioned coupling means comprise a tongue and a groove, whereby this groove is bordered by a lip on the bottom side, the top side respectively, hereafter called the lower lip and the upper lip respectively, whereby the distal end of the upper lip defines a vertical plane, hereafter called plane V1;</li><li>the lower lip is longer than the upper lip;</li><li>there is an interlocking part on the part of the lower lip which extends past the free end of the upper lip, with a contact surface which, when coupled, works in conjunction with a contact surface which is provided on the other panel, whereby these contact surfaces form a contact zone when coupled, whose center defines a vertical plane, hereafter called plane V2;</li><li>before the above-mentioned interlocking part, in the direction of the groove, is formed a space in the lower lip which is open on the top side;</li><li>in the coupled situation, there is a contact zone in the cross section in which the top side of the tongue makes contact with the bottom side of the upper lip, whereby the point of this contact zone which is situated most inwardly defines a first vertical plane, hereafter called plane V3, the most outwardly situated point of this contact zone defines a second vertical plane, hereafter called plane V4, and both planes V3 and V4 define a vertical plane situated right in between, hereafter called plane V5;</li><li>the top side of the interlocking part defines a horizontal level, hereafter called level N1;</li><li>the bottom side of the part upon which the tongue is provided and which extends from the tip of the tongue to the interlocking zone, defines a horizontal level, hereafter called level N2;</li><li>the levels N1 and N2 define a horizontal level situated right in between, hereafter called level N3;</li><li>the average height of the contact zones between the top side of the tongue and the bottom side of the upper lip define a horizontal level, hereafter called level N4;</li><li>the distance between the planes V1and V2 is at least half of the distance between the levels N3 and N4;</li></ul> characterized in that the floor covering further provides at least in the combination of the following characteristics: <ul id="ul0002" list-style="dash" compact="compact"><li>that the panels, and basically also the above-mentioned lips, are made of fiberboard of the type MDF or HDF;</li><li>that the coupling means are made such that the panels can be assembled by pushing them towards one another; and</li><li>that the above-mentioned space extends to beneath the upper lip, such that this space is in conformity with at least one of the following two characteristics: <ol id="ol0001" compact="compact" ol-style=""><li>a) that the part of this space which is situated under the level N3 extends inwardly to at least past the plane V1;</li><li>b) that the part of this space which is situated under the level N1 extends inwardly to at least past the plane V5.</li></ol></li></ul>

When all the above-mentioned criteria are met, an embodiment is obtained whereby the above-mentioned space is relatively large compared to the other parameters on the one hand, and, thanks to the specific application of the MDF or HDF material, the structure nevertheless remains sufficiently stable on the other hand. The relatively large space which is formed in the lower lip offers the advantage that the tongue can take place in the groove more easily, as well as the advantage that the tongue can be made relatively massive.

According to a particular embodiment, this floor covering is characterized in that the panels are rectangular and in that coupling means are formed on both pairs of edges which offer an interlocking in the horizontal and vertical direction, whereby these coupling means are formed as mentioned above on at least one pair of said edges, and whereby on at least two edges standing at right angles to one another, use is made of a groove which is bordered by an upper lip and a lower lip respectively, whereby the lower lip each time protrudes further than the upper lip, such that two such longer lips meet in at least one angle of the panel, whereby at least the above-mentioned space continues up to the end of the panel in said angle, in other words extends through the far end of the lip standing at right angles.

As the above-mentioned space is made continuous, also a large flexibility can be guaranteed in the angle concerned, as the interlocking parts of the longitudinally directed lower lip and the transversely directed lower lip are then disconnected by this continuous recess.

An eight aspect, which is a non-claimed embodiment, provides for a floor covering consisting of hard panels, whereby these panels are provided with coupling means on at least two opposite edges made in one piece with the panels, as a result of which several of such panels can be mutually coupled to one another, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned, and parallel to the plane of the floor covering, and whereby: <ul id="ul0003" list-style="dash" compact="compact"><li>the above-mentioned coupling means comprise a tongue and a groove, whereby this groove is bordered by a lip on the bottom side, the top side respectively, hereafter called the lower lip and the upper lip respectively;</li><li>the lower lip is longer than the upper lip;</li><li>there is an interlocking part on the part of the lower lip which extends past the free end of the upper lip, with a contact surface which, when coupled, works in conjunction with a contact surface which is provided on the other panel; and</li><li>before the above-mentioned interlocking part, in the direction of the groove, is formed a space in the lower lip which is open on the top side;</li></ul> characterized in that the coupling means are made such that the panels can be assembled by pushing them towards one another, and in that in the bottom side of the part onto which the tongue is provided, and which extends from the tip of the tongue up to the interlocking zone, is provided an excavation, such that this excavation co-operates with the interlocking part in a position in which the tongue is situated in front of the groove. Thus is obtained that, while the tongue is being fit in, something as if it were falls down at the time when the interlocking part takes place in the excavation, so that, next, the tongue is better positioned in front of the groove of the other panel.

The floor coverings consisting of hard panels known until now, and which allow for a glueless interlocking, do not make it possible to temporarily remove panels from the middle of the floor covering after the floor covering has been entirely laid. This is disadvantageous in that it is difficult to replace damaged panels, as well as impossible to locally remove the floor covering, for example to work on or in the rough floor, to lay or remove cables under the floor covering, etc. With the known systems, the panels always need to be systematically removed as of an edge of the floor covering.

A ninth aspect, which is a non-claimed embodiment, aims a floor covering made of hard panels, whereby it is possible to remove any panel whatsoever from an existing floor covering, and to put it back, without the floor covering having to be systematically broken up as of an edge of the whole.

This ninth aspect to this end provides for a floor covering consisting of hard panels, whereby these panels are provided with coupling means on at least two opposite edges made in one piece with the panels, as a result of which several of such panels can be mutually coupled to one another, whereby these coupling means provide for an interlocking in a direction perpendicular to the plane of the floor covering, as well as in a direction perpendicular to the edges concerned, and parallel to the plane of the floor covering, whereby the above-mentioned coupling means are made such that two coupled panels, starting from a flat position, can be turned towards one another with their bottom sides over at least a certain angle on the one hand, and this turning movement makes it possible for said two panels to be removed from in between adjacent panels on the other hand.

According to a first preferred embodiment, the coupling means are made such that they make it possible for the two panels, when they are situated in a floor covering, to be lifted with their coupled edges, such that there is a disconnection on at least one of the opposite edges providing for a connection with the adjacent panels.

According to a second preferred embodiment, the coupling means are made such that they make it possible for the two panels, when they are situated in a floor covering, to be lifted with their coupled edges, such that the coupling, in particular the vertical coupling, is interrupted on the edges concerned and a disconnection becomes possible.

According to a particularly practical embodiment, the floor covering is characterized in that the coupling means mainly consist of a tongue and a groove, whereby the lip which is situated on the bottom side of the groove is longer than the lip on the top side, and the interlocking is obtained mainly in the horizontal direction thanks to an interlocking part on the lip situated on the bottom side of the groove and an interlocking part working in conjunction with it on the bottom side of the other panel, whereby these coupling means make it possible for the panels to be assembled by means of a turning movement and whereby, in the coupled position, spaces are provided above the first-mentioned interlocking part as well as under the second-mentioned interlocking part which allow for a further turning movement.

The above-described second, third and sixth to ninth aspects can be combined with the first aspect, to which the claimed invention relates, provided the embodiments as described do not have any contradictory qualities.

Naturally, the invention also concerns panels with which the above-described floor coverings can be made.

In order to better explain the characteristics of the invention, the following preferred embodiments are described as an example only without being limitative in any way, with reference to the accompanying drawings, in which: <ul id="ul0004" list-style="none" compact="compact"><li><figref idref="f0001">figure 1</figref> schematically represents a hard panel;</li><li><figref idref="f0001">figure 2</figref> schematically represents a part of a floor covering made of hard panels;</li><li><figref idref="f0002">figure 3</figref> represents an embodiment of coupling means applied in a floor covering according to the invention, seen from a section which corresponds for example to section III-III in <figref idref="f0001">figure 2</figref>;</li><li><figref idref="f0001">figure 4</figref> represents a section according to line IV-IV in <figref idref="f0001">figure 2</figref>;</li><li><figref idref="f0001">figure 5</figref> represents a variant of <figref idref="f0001">figure 4</figref>;</li><li><figref idref="f0003">figures 6 to 8</figref> represent the coupling means from <figref idref="f0002">figure 3</figref> in different positions;</li><li><figref idref="f0004">figure 9</figref> represents a variant of the coupling means from <figref idref="f0002">figure 3</figref>;</li><li><figref idref="f0004">figure 10</figref> represents another variant, not belonging to the invention;</li><li><figref idref="f0004 f0005">figures 11 to 13</figref> represent the variant from <figref idref="f0004">figure 10</figref> in different positions;</li><li><figref idref="f0005">figure 14</figref> represents another variant, not belonging to the invention;</li><li><figref idref="f0006">figure 15</figref> represents yet another variant, not belonging to the invention;</li><li><figref idref="f0007">figures 16 and 17</figref> represent the coupling means from <figref idref="f0006">figure 15</figref> in two other positions;</li><li><figref idref="f0007">figure 18</figref> represents an angular part of a panel;</li><li><figref idref="f0008">figure 19</figref> represents a section of another embodiment, not belonging to the invention;</li><li><figref idref="f0008">figure 20</figref> represents a section of another embodiment of a floor covering according to the invention;</li><li><figref idref="f0008">figure 21</figref> represents the part indicated by F21 in <figref idref="f0008">figure 20</figref> to a larger scale;</li><li><figref idref="f0009">figure 22</figref> represents how the panels of the floor covering from <figref idref="f0008">figure 20</figref> can be disconnected, connected respectively;</li><li><figref idref="f0009">figure 23</figref> represents the part indicated by F23 in <figref idref="f0009">figure 22</figref> to a larger scale;</li><li><figref idref="f0010">figure 24</figref> represents a view analogous to that in <figref idref="f0008">figure 21</figref> for another variant;</li><li><figref idref="f0010">figure 25</figref> represents how the panels of <figref idref="f0010">figure 24</figref> can be mutually disconnected, connected respectively;</li><li><figref idref="f0010">figure 26</figref> represents the part indicated by F26 in <figref idref="f0010">figure 25</figref> to a larger scale.</li></ul>

As represented in <figref idref="f0001">figures 1 and 2</figref>, the invention concerns a floor covering 1, as well as the hard panels 2 of which such a floor covering 1 is made.

As described in international patent application No. <patcit id="pcit0003" dnum="WO9747834A"><text>97/47834</text></patcit>, it is known that such panels 2 can be connected without any glue being required by making use of coupling means which, when the panels 2 are rectangular, provide for an interlocking in a direction R1 perpendicular to the plane of the floor covering 1, at least on one pair of opposite edges 3-4, and preferably on both pairs of edges 3-4, 5-6 respectively, as well as in a direction R2 perpendicular to the edges 3-4 or 5-6 concerned, and parallel to the plane of the floor covering 1.

Coupling means can be used hereby which allow for different coupling methods, but preferably a coupling by rotating as well as by pushing the panels together. The latter makes it possible for such panels 2 to be coupled to one another in a known manner by first rotating them into one another on their edges 3-4, as represented by means of the panel 2A in <figref idref="f0001">figure 2</figref> with a movement of rotation W1, and by subsequently snapping them together on their edges 5-6 by means of a translation T1. According to a variant, the connection on the edges 3-4 of the panels 2 concerned, can also be realized by starting from a position as is schematically indicated by reference 2B, and by coupling the panel 2 concerned by means of a translation T2.

Also, while a panel 2A is maintained in the rotated position, a following panel 2C can be coupled to the edges 5 and 6 concerned, either by means of a translation T3, or by means of a mutual rotation between the panels 2A and 2C, after which both panels 2A and 2C are then turned down so as to be locked to the preceding row of panels.

As mentioned in the introduction, the present invention aims different new embodiments of coupling means to mutually connect such panels 2.

<figref idref="f0002">Figure 3</figref> represents an embodiment according to the above-mentioned first aspect, to which the invention relates.

Also, in this embodiment, the floor covering 1 consists of hard panels 2 which are provided with coupling means 7 made in one piece with the panels 2 on at least two opposite edges, in this case 5-6, so that several of such panels 2 can be mutually connected to one another. These coupling means 7 provide for an interlocking in the direction R1, as well as R2.

Further, these coupling means 7 have a tongue 8 provided on the edge 5, and a groove 9 provided on the edge 6, in which the tongue 8 fits. The groove 9 is hereby bordered on the top side by means of a lip 10, hereafter called the upper lip. At the bottom, it is bordered by a lip 11, hereafter called the lower lip, which is longer than the top lip 10, in other words, which extends further than the distal end 12 of the lip 10 in the horizontal direction.

The interlocking in the direction R2 is obtained as the lower lip 11 forms an interlocking part 13 with an inwardly directed contact surface 14 which can co-operate with an opposite contact surface 15 formed on the edge 5 when being coupled.

According to the invention, the edge 5 which is provided with the tongue 8 is made flexible, whereas the lip 11 is preferably made rigid, the latter by making it relatively thick, as is clearly visible in <figref idref="f0002">figure 3</figref>.

The edge 5 is made such that it can bend in several places. Thus, for example, the tongue 8 is flexible, but even more important is that this tongue 8 is, according to the invention, situated on a part 16, as represented, which is connected to the actual panel 2 via a flexible zone 17 in the shape of a local constriction.

This flexible zone 17 is preferably situated on the place as indicated in <figref idref="f0002">figure 3</figref>, in other words seen as of the tongue 8, past the contact surface 15, and said flexible zone 17 has a thickness D1, according to the direction R1, which is smaller than half the thickness of the panels 2. This thickness D1 may be smaller than 2/3 of the thickness D2 of the part 16 upon which the tongue 8 is situated.

If the panels 2 are made of fiberboard, of the type MDF or HDF, the thickness D1 is preferably even smaller than 3 mm, and better still smaller than 2 mm.

The flexible zone 17 is situated against the top side 18 of the panel 2 concerned, which is particularly useful when MDF or HDF board is used, as such materials have a larger density on the outer surfaces, and thus the thickness on these places can be maximally reduced so as to obtain an optimal flexibility.

Apart from the advantages already mentioned in the introduction, the invention also offers the following advantageous characteristics: <ul id="ul0005" list-style="dash" compact="compact"><li>As the contact surface 14 is situated relatively high, said contact surface 14 can be provided in a more vertical position, without much deviation from the tangential directions P1 and P2 represented in <figref idref="f0002">figure 3</figref>. Thus is obtained a solid interlocking.</li><li>As the flexibility of the connection is situated in the top side of the panel, this results in the interlocking being pulled even more tightly together when a tensile force is exerted on the panels.</li><li>In the design of <figref idref="f0002">figure 3</figref> is created a stress concentration on the top side of the panel 2, right behind the tongue 8, which results in a bending. As a consequence, the stress concentration is transferred to the strongest place of the board. During the joining, it is practically impossible for forces to be created in the deepest point of a groove 9, so that it is almost excluded that splits are created at this deepest point.</li></ul>

According to the above-mentioned second aspect, which in the given example of <figref idref="f0002">figure 3</figref> is combined with the above-mentioned first aspect, the coupling means 7 consist at least of first coupling parts formed of contact surfaces 19-20 working in conjunction with one another, on the top side of the tongue 8 and the bottom side of the upper lip 10 respectively; second coupling parts formed of contact surfaces 21-22, on the top side of the lower lip 11 and the opposite part 16 of the other panel 2 respectively; and third coupling parts which provide for the horizontal interlocking situated on the lower lip 11, but further than the free end 12 of the upper lip 10, formed of the above-mentioned contact surfaces 14 and 15. What is special here, is that the third coupling parts are situated between the first and the second ones.

The second coupling parts are preferably situated immediately next to the third coupling parts. The contact surface 21 is hereby formed of the top side of the above-mentioned interlocking part 13, whereas the contact surface 22 is situated precisely opposite to it.

According to the embodiment of <figref idref="f0002">figure 3</figref>, there is a free space 23 under the tongue 8 which extends as of the tip 24 of the tongue 8 up to the third coupling parts, in other words the contact surface 14.

The coupling means 7 are mainly designed to be provided on one pair of edges 5-6, whereas coupling means 25 are preferably provided on the other edges 3-4, as represented in <figref idref="f0001">figure 4 or figure 5</figref>, which are described in international patent application No. <patcit id="pcit0004" dnum="WO9747834A"><text>97/47834</text></patcit> and which make it possible for the panels 2 concerned to be assembled along their top edges, disassembled respectively, at least by means of a movement of rotation. In the case where the panels 2, as represented, are longitudinal, the coupling means 7 will preferably be provided on the short edges 5-6.

What precedes does not prevent, however, that the coupling means 7 are provided on both pairs of edges 3-4 and 5-6, or on the longitudinal edges 3-4, whereas another connection is provided for on the short edges.

Nor is it excluded to provide the panels 2 on merely one pair of edges with coupling means, in this case the coupling means 7.

Further, the coupling means 7 are preferably made such that the panels 2 with their edges concerned, in this case the edges 5 and 6, can be connected to one another by pushing the panels 2 freely towards one another, as is represented step by step in <figref idref="f0003">figures 6 to 8</figref>, and as will be further described into more detail. Moreover, the coupling means 7 are made such that the edges concerned, in this case the edges 5 and 6, can also be connected to one another by means of a movement of rotation, disconnected respectively, as is represented by means of a dot and dash line in <figref idref="f0002">figure 3</figref>.

The laying of the floor covering 1, with panels 2 containing coupling means 7, can then for example, yet not necessarily, be carried out as follows. In a situation as represented in <figref idref="f0001">figure 2</figref>, the panel 2A is first connected with its edge 3 to an edge 4 of already laid panels by presenting the panel 2A at an angle and by rotating the above-mentioned edges 3-4 into one another, so that a connection such as for example in <figref idref="f0001">figure 4</figref>, or, as an alternative, <figref idref="f0001">figure 5</figref>, is created.

Then, the panel 2A can be connected to the preceding panel with a translation T1, whereby the situations as represented in <figref idref="f0003">figures 6 to 8</figref> are successively witnessed on the coupling means 7. It is clear that this is accompanied by a bending in the tongue 8, and to a larger extent also in the flexible zone 17, whereby the part 16 with the contact surface 15 finally snaps down behind the contact surface 14.

<figref idref="f0004">Figure 9</figref> represents an embodiment which is realized according to the above-mentioned third aspect. The coupling means 26 used hereby represent first coupling parts analogous to the coupling means 7, formed by contact surfaces 19 and 20, and third coupling parts formed by contact surfaces 14 and 15. What is special hereby, is that the above-mentioned second coupling parts are situated between the first and third ones, and that the second coupling parts consist of contact surfaces 27-28 working in conjunction with one another and which define a local contact zone 29 which is situated in the middle or practically in the middle between the tip 24 of the tongue 8 and the third coupling parts, in other words the contact surface 14.

As represented in <figref idref="f0004">figure 9</figref>, a bulge 30 can be provided in the lower lip 11 on the contact zone 29.

<figref idref="f0004 f0005">Figures 10 to 13</figref> represent an embodiment for different positions with coupling means 31 which are in conformity with the above-mentioned fourth aspect. The upper lip 10 is hereby longer than the lower lip 11, and the coupling means 25 which realize the interlocking in the horizontal direction consist of coupling parts formed of contact surfaces 32-33 working in conjunction with one another, which are provided on the bottom side of the upper lip 10, outside the distal end of the lower lip 11, and on the opposite part of the edge of the other panel 2 respectively.

The coupling means 31 are hereby made such that the connection can be realized by pushing the panels 2 towards one another with the edges 5-6 concerned, for example over a base, whereby they systematically fit into one another, as represented in <figref idref="f0004 f0005">figures 10 to 12</figref>.

As shown in the figures, the tongue 8 has one end 34 which has been made thinner. There is also a free space 35 between the free end 36 of the lower lip 11 and the opposite part 37 under the tongue 8 of the other panel 2.

The embodiment of <figref idref="f0004 f0005">figures 10 to 13</figref> also illustrates the fifth aspect, in other words that the edges, in this case the edges 5-6, are provided with coupling means 31 which make it possible for the panels 2 concerned to be mutually disconnected by rotating them with their bottom sides 38 down and towards one another, as is specifically shown in <figref idref="f0005">figure 13</figref>. The above-mentioned space 35 is helpful thereby.

The embodiment of <figref idref="f0004 f0005">figures 10 to 13</figref> also corresponds to the sixth aspect, characterized in that the interlocking in the horizontal direction is formed of coupling parts in the shape of a local protrusion 39 in the top side 40 of the above-mentioned tongue 8, which meshes in a recess 41 in the upper lip 10.

<figref idref="f0005">Figure 14</figref> represents a variant which also applies the above-mentioned characteristics of the sixth aspect.

Other particularities of this embodiment, which must not all be combined according to variants which are not represented, consist in that the top side 40 of the tongue 8, with the exception of the local protrusion 39, is mainly parallel to the surface of the floor covering 1, and in that the bottom side 42 of the tongue 8 is mainly formed of a smoothly bent surface which reaches up to the top side 40 of the tongue 8. Also this embodiment makes it possible for the panels 2 to be assembled by means of a mainly horizontal movement.

<figref idref="f0006">Figure 15</figref> represents a connection with coupling means 43 realized according to the above-mentioned seventh aspect. It concerns a connection whereby: <ul id="ul0006" list-style="dash" compact="compact"><li>the coupling means 43 comprise a tongue 8 and a groove 9, whereby this groove 9 is bordered on the bottom side, the top side respectively, by a lip, hereafter called the lower lip 11 and the upper lip 10 respectively, whereby the distal end 12 of the upper lip 10 defines a vertical plane, hereafter called plane V1;</li><li>the lower lip 11 is longer than the upper lip 10;</li><li>there is an interlocking part 13 on the part of the lower lip 11 which extends past the free end 12 of the upper lip 10, with a contact surface 14 which, when coupled, works in conjunction with a contact surface 15 which is provided on the other panel 2, whereby these contact surfaces 14-15 form a contact zone when coupled, whose center M1 defines a vertical plane, hereafter called plane V2;</li><li>before the above-mentioned interlocking part 13, in the direction of the groove 9, is formed an open space 44 in the lower lip 11 which is open on the top side;</li><li>in the coupled situation, there is a contact zone in the cross section in which the top side of the tongue 8 makes contact with the bottom side of the upper lip 10, whereby the point C3 of this contact zone which is situated most inwardly defines a first vertical plane, hereafter called plane V3, the most outwardly situated point C4 of this contact zone defines a second vertical plane, hereafter called plane V4, and both planes V3 and V4 define a vertical plane situated right in between, hereafter called plane V5;</li><li>the top side of the interlocking part 13 defines a horizontal level, hereafter called level N1;</li><li>the bottom side of the part 16 upon which the tongue 8 is provided and which extends from the tip 24 of the tongue 8 to the interlocking zone, defines a horizontal level, hereafter called level N2;</li><li>the levels N1 and N2 define a horizontal level situated right in between, hereafter called level N3;</li><li>the average height of the contact zone between the top side of the tongue 8 and the bottom side of the upper lip 10 define a horizontal level, hereafter called level N4;</li><li>the distance between the planes V1 and V2 is at least half of the distance between the levels N3 and N4.</li></ul>

This floor covering 1 is special in that it provides at least in the combination of the following characteristics: <ul id="ul0007" list-style="dash" compact="compact"><li>that the panels 2, and basically also the above-mentioned lips 10-11, are made of fiberboard of the type MDF or HDF;</li><li>that the coupling means 43 are made such that the panels 2 can be assembled by pushing them towards one another; and</li><li>that the above-mentioned space 44 extends to beneath the upper lip 10, such that this space 44 is in conformity with at least one of the following two characteristics: <ol id="ol0002" compact="compact" ol-style=""><li>a) that the part of this space 44 which is situated under the level N3 extends inwardly to at least past the plane V1;</li><li>b) that the part of this space 44 which is situated under the level N1 extends inwardly to at least past the plane V5.</li></ol></li></ul>

Thanks to this specific combination is obtained a space 44 which acts as an excavation in relation to the other dimensions extending over a relatively large distance in the direction R2, as a result of which the advantages mentioned in the introduction are obtained. In spite of the relatively large excavation and, consequently, the fact that the lower lip 11 is relatively thin, the rigidity remains nevertheless sufficient thanks to the use of MDF or HDF as a base material, which has a layered fibrous structure.

The distance between the levels N1 and N2 is preferably smaller than 1/3 of the distance between the levels N2 and N4. Thus, the obstruction formed by the interlocking part 13 while the panels are being pushed together, is restricted to a minimum, as a result of which the panels 2 can smoothly slide into one another.

Further, the intersection P4 between the plane V4 and the bottom side of the tongue 8 is situated beneath level N1, seen from a cross section, and better still beneath level N3. The tongue 8 thus obtains a relatively large thickness, which improves its rigidity. Further, it is even more indicated for the section P5 between the plane V5 and the bottom side of the tongue 8 to be situated beneath level N1, and better still beneath level N3.

In particular, the section P3 between the plane V3 and the bottom side of the tongue 8 will be situated beneath level N1, and better still beneath level N3.

According to a preferred characteristic of the seventh aspect, the part of the above-mentioned space 44 situated under the plane N3 extends at least inwardly up to the vertical plane V6 which is determined by the tip 24 of the tongue 8.

In the case where the panels 2 are rectangular and coupling means are formed on both pairs of edges 3-4 and 5-6 which provide for a vertical and a horizontal interlocking, whereby both edges 4 and 6 have a lower lip 11, 11A respectively, which is longer than the upper lip 11, at least the above-mentioned space 44 is preferably made continuous up to the end of the panel 2, as represented in <figref idref="f0007">figure 18</figref>, in the angle 45, in other words it extends through the far end of the square lip 10A, in particular the interlocking part 13A thereof. As the space 44 is relatively large on the one hand, and this space 44 extends through the interlocking part 13A on the other hand, and the interlocking parts 13 and 13A are disconnected from one another, a particularly flexible angle is obtained, which makes it easier to assemble the panels.

<figref idref="f0008">Figure 19</figref> illustrates the above-mentioned eight aspect, whereby an excavation 46 is provided in the bottom side of the tongue 8, such that in the mutual position of the two panels 2 as represented in <figref idref="f0008">figure 19</figref>, the tongue 8 is better positioned in front of the groove.

It should be noted that in all the above-mentioned embodiments, the contact surfaces providing for the horizontal interlocking are preferably directed slantingly in relation to the plane of the floor covering 1. This does not exclude, however, that according to a variant, one or both contact surfaces can also be directed perpendicular to the plane of the floor covering. The contact surfaces can also be bent as such, whereby the tangent line in the middle of the contact zone determines the above-mentioned gradient.

In the case where these contact surfaces, or their tangent line, are directed slantingly, they preferably extend in a direction which is tangential or almost tangential to a circle, whose center is situated on a point of rotation around which the panels 2 can be turned apart. As indicated in <figref idref="f0002">figure 3</figref>, this means that the gradient or direction B1 of the contact surfaces deviates only little from the gradient of the tangent B2 onto the circle C.

In order to provide for a snap-in effect, the direction B1 pertaining to the contact surfaces preferably does deviate from the direction of the above-mentioned tangent B2 and is directed inwardly, such that a snap-in effect is created when the panels are rotated into one another, whereby the above-mentioned direction B1 deviates 30° at the most from the above-mentioned tangential direction B2.

What precedes can be applied in all the rotatable embodiments described above, also in the embodiments whereby the panels 2 are rotated apart by turning them down.

The coupling means which are realized according to one or several of the first eight aspects are all particularly suitable to be provided on edges 3-4 and/or 5-6, whereby it must be possible to assemble the panels 2 by shifting them.

In the case where the panels 2 are rectangular, in other words square or longitudinal, they are preferably provided with coupling parts on all four edges 3-4 and 5-6 which allow for a vertical and a horizontal interlocking, whereby coupling means as described in one or several of the above-mentioned first eight aspects are then provided on at least two opposite edges 3-4 or 5-6.

In the case where the panels 2 are rectangular, the new coupling means are preferably provided at least on the short edges 5-6. Further, coupling means are then preferably provided on the long edges 3-4 which allow for an assembly, disassembly respectively by means of a movement of rotation, which can be of a known nature or which can also be made according to any of the above-mentioned eight aspects.

<figref idref="f0008 f0009">Figures 20 to 23</figref> show an embodiment according to the ninth aspect. According to this ninth aspect, it concerns a floor covering 1, consisting of hard panels 2, whereby these panels 2 are provided on at least two opposite edges, in the case of elongated panels 2 preferably on the longitudinal edges 3-4, with coupling means 7 made in one piece with the panels 2, so that several of such panels 2 can be mutually connected to one another, whereby these coupling means 7 provide for an interlocking in a direction R1 perpendicular to the plane of the floor covering 1, as well as in a direction R2 perpendicular to the edges 3-4 concerned, and parallel to the plane of the floor covering 1, whereby the above-mentioned coupling means 7 are made such that two connected panels 2 can be turned towards one another with their bottom side, starting from a flat position, over at least a certain angle on the one hand, whereby this turning movement makes it possible for the two above-mentioned panels 2 to be removed from between other adjacent panels 2D and 2E on the other hand.

Moreover, according to the embodiment of <figref idref="f0008 f0009">figures 20 to 23</figref>, the coupling means 7 are made such that, as represented in <figref idref="f0009">figure 22</figref>, they make it possible for the two panels 2 to be lifted with their coupled edges 3-4, from a flat position, such that there is a disconnection on at least one of the opposite edges which provide for the connection with the adjacent panels 2D and 2E. Thus, the panels 2 can be removed from an existing floor covering 1 by first lifting them as mentioned above and by subsequently turning the left panel 2 from <figref idref="f0009">figure 22</figref> up, as represented by means of a dot and dash line, so that the left panel 2 of <figref idref="f0009">figure 22</figref> can be removed. Next, also the right panel 2 can be removed. The initial lifting of the panels 2 can take place in any way whatsoever, for example by means of a suction cup or by sticking a hook or such through an opening made in the floor covering, for example a bore hole.

<figref idref="f0008 f0009 f0010">Figures 20 to 26</figref> represent variants whereby the coupling means 7 are made such that they make it possible for the two panels 2 to be lifted, from a flat position, with their coupled edges 3-4, such that the connection, in particular the vertical connection on the edges 3-4 concerned is undone. In this case, it is not necessary to disconnect the panels 2D and/or 2E first in order to disconnect the two panels 2.

Both in the embodiment of <figref idref="f0008 f0009">figures 20 to 23</figref> and in the one of <figref idref="f0010">figures 24 to 26</figref>, the coupling means 7 mainly consist of a tongue 8 and a groove 9, whereby the lip 11 which is situated on the bottom side of the groove 9 is longer than the lip 10 on the top side, and the interlocking is mainly obtained in the horizontal direction by means of an interlocking part 13 on the lip 11 and an interlocking part 47 on the bottom side of the other panel 2 working in conjunction with it, whereby these coupling means 7 make it possible for the panels 2 to be assembled by means of a turning movement, and whereby, in the coupled position, there are spaces 48-49 above the first-mentioned interlocking part 13, as well as under the second-mentioned interlocking part 47, which allow for a further turning.

Practically, the above-mentioned interlocking parts 13-47 are positioned such that a lateral play S is created during the above-mentioned further turning, as is schematically represented in <figref idref="f0008">figure 21</figref>, so that a certain freedom of movement is obtained which is desirable in order to remove the panels 2 from between the fixed panels 2D and 2E.

In the embodiment of <figref idref="f0010">figures 24 to 26</figref>, this lateral play S, as well as the design of the tongue 8 and the groove 9, are selected such that the right panel 2, in the situation of <figref idref="f0010">figure 26</figref>, comes loose so to say and can simply be removed from the left panel 2.

In particular, the distance Z1 between the tip of the tongue 8 and the interlocking part 47 situated on the same edge is smaller than or equal to the distance Z2 between the tip of the lip 10 bordering the top side of the groove 9 and the interlocking part 13 situated on the lip 11 bordering the bottom side of the groove 9.

It should be noted that in the embodiments of <figref idref="f0008 f0009 f0010">figures 20 to 26</figref>, the tongue 8 is preferably made such that it can make a movement of rotation in the groove 9, as said tongue 8 is more or less round, as represented in <figref idref="f0008 f0009">figures 20 to 23</figref>, or because it is relatively short, as represented in <figref idref="f0010">figures 24 to 26</figref>.

As represented, coupling means are preferably provided both on the short edges and on the longitudinal edges which allow for an interlocking both in the vertical and in the horizontal direction, whereby they can all be made such that they allow for a connection and disconnection as described above by means of <figref idref="f0008 f0009 f0010">figures 20 to 26</figref>. It is also possible to apply the coupling means represented in these figures only on the longitudinal edges, whereas coupling means with another shape are applied on the short sides, for example as represented in <figref idref="f0001">figure 4</figref>.