Floor covering

Abstract

Hard panels formed from a wood-based material and having a decorative layer for floor coverings are provided, at least on two opposite edges, with coupling devices made in one piece with the panels wherein similar panels may be coupled together to form a floor covering, wherein these coupling devices provide for an interlocking in a direction perpendicular to the plane of coupled panels, as well as in a direction perpendicular to the edges concerned and parallel to the plane of coupled panels. These coupling devices are constituted of a tongue and a groove. The top side of the tongue has a protrusion that cooperates with a meshing recess located in the lower side of the upper lip of the groove of the coupling devices, and a portion extending generally parallel with the plane of the panel to form a contact surface cooperating with the lower side of the upper lip of the groove.

Claims

1. A floor panel for forming a floor covering, wherein the floor panel is a laminate panel made of a board on the basis of wood, upon which one or several layers, including a decorative layer, are provided; wherein the floor panel is provided on at least two opposite edges with coupling parts made in one piece with the floor panel, as a result of which two of such floor panels can be mutually coupled to one another; wherein said coupling parts, in a coupled situation, provide for an interlocking in a direction perpendicular to a 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; wherein said coupling parts comprise a tongue and a groove, said groove being bordered by an upper lip and a lower lip, the distal end of the upper lip defining a vertical plane that forms a closing plane between two of such coupled floor panels, said lower lip extending further than said vertical plane; wherein said coupling parts comprise first cooperating surfaces, on the top side of the tongue and the bottom side of the upper lip respectively, said first cooperating surfaces, in the coupled situation, working in conjunction with one another and forming a first cooperating zone, and second cooperating surfaces, on an interlocking part that is situated on the lower lip and on an opposite part of the other floor panel respectively, said second cooperating surfaces, in the coupled situation, working in conjunction with one another and forming a second cooperating zone; wherein said coupling parts are made such that two of such floor panels can be assembled by pushing towards one another by means of a movement mainly parallel to the plane of the floor covering; wherein the distal tip of said tongue, in the coupled situation, is situated in said groove past said vertical plane; wherein a distance between said vertical plane and the distal end of the lower lip is smaller than a thickness of the floor panel but larger than a distance between said vertical plane and the distal tip of the tongue in the coupled situation; wherein the distance between the distal tip of the tongue and said vertical plane in the coupled situation is smaller than the distance between a horizontal level defined by a height of said first cooperating zone and an intersection between said vertical plane and the top side of the lower lip; and wherein the floor panel shows one or both of the following characteristics: a thickness of the upper lip is larger than a thickness of the lower lip at said vertical plane; the distance between said vertical plane and the distal end of the lower lip is smaller than the distance between the upper side of the floor panel and the intersection between said vertical plane and the top side of the lower lip.

2. The floor panel of claim 1, wherein the uppermost point of the top side of said interlocking part defines a second horizontal level; wherein the lowermost point of the bottom side of the tongue defines a third horizontal level; and wherein the distance between said second and third horizontal level is smaller than of the distance between said first and third horizontal level.

3. The floor panel of claim 1, wherein the tongue and the groove are made such that when two of such floor panels are freely pushed towards one another, over a base or such, the tongue automatically ends up in the groove.

4. The floor panel of claim 1, wherein said interlocking part is situated on a part of the lower lip that is situated past said vertical plane.

5. The floor panel of claim 1, wherein said cooperating surfaces forming the second cooperating zone, or their tangent line, are directed slantingly in relation to the plane of the floor covering.

6. The floor panel of claim 1, wherein said coupling parts are made such that the coupling parts can be turned in and/or out one another by means of a movement of rotation.

7. The floor panel of claim 1, wherein said board is fiberboard of the type MDF or HDF.

8. The floor panel of claim 7, wherein said decorative layer is selected from the group consisting of: a printed paper layer, a layer of wood, a veneer layer and a cork layer.

9. The floor panel of claim 1, wherein said decorative layer is selected from the group consisting of: a layer of wood, a veneer layer and a cork layer.

10. The floor panel of claim 1, wherein the floor panel is rectangular, said floor panel comprising a first pair of opposite edges, formed by the aforementioned two opposite edges, and a second pair of opposite edges, which is also provided with coupling parts at least offering a locking in the horizontal direction.

11. A floor panel for forming a floor covering, wherein the floor panel is a laminate panel made of a board on the basis of wood, upon which one or several layers, including a decorative layer, are provided; wherein the floor panel is provided on at least two opposite edges with coupling parts made in one piece with the floor panel, as a result of which two of such floor panels can be mutually coupled to one another; wherein said coupling parts, in a coupled situation, provide for an interlocking in a direction perpendicular to a 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; wherein said coupling parts comprise a tongue and a groove, said groove being bordered by an upper lip and a lower lip, the distal end of the upper lip defining a vertical plane that forms a closing plane between two of such coupled floor panels, said lower lip extending further than said vertical plane; wherein said coupling parts comprise first cooperating surfaces, on the top side of the tongue and the bottom side of the upper lip respectively, said first cooperating surfaces, in the coupled situation, working in conjunction with one another and forming a first cooperating zone, and second cooperating surfaces, on an interlocking part that is situated on the lower lip and on an opposite part of the other floor panel respectively, said second cooperating surfaces, in the coupled situation, working in conjunction with one another and forming a second cooperating zone; wherein said interlocking part is the only interlocking part being situated on the lower lip and taking part in said interlocking in the direction parallel to the plane of the floor covering and perpendicular to the edges; wherein said coupling parts are made such that two of such floor panels can be assembled by pushing towards one another by means of a movement mainly parallel to the plane of the floor covering; wherein the distal tip of said tongue, in the coupled situation, is situated in said groove past said vertical plane; wherein a distance between said vertical plane and the distal end of the lower lip is smaller than a thickness of the floor panel; wherein, in the coupled situation, there is a free space under the tongue, which extends from the distal tip of the tongue at least up to a point being situated further than a second vertical plane being defined by the most inwardly situated point of said first cooperating zone; and wherein the floor panel shows one or both of the following characteristics: a thickness of the upper lip is larger than a thickness of the lower lip at said vertical plane; the distance between said vertical plane and the distal end of the lower lip is smaller than the distance between the upper side of the floor panel and an intersection between said vertical plane and the top side of the lower lip.

12. The floor panel of claim 11, wherein the uppermost point of the top side of said interlocking part defines a second horizontal level; wherein the lowermost point of the bottom side of the tongue defines a third horizontal level; and wherein the distance between said second and third horizontal level is smaller than of the distance between said first and third horizontal level.

13. The floor panel of claim 11, wherein the tongue and the groove are made such that when two of such floor panels are freely pushed towards one another, over a base or such, the tongue automatically ends up in the groove.

14. The floor panel of claim 11, wherein said interlocking part is situated on a part of the lower lip that is situated past said vertical plane.

15. The floor panel of claim 11, wherein said cooperating surfaces forming the second cooperating zone, or their tangent line, are directed slantingly in relation to the plane of the floor covering.

16. The floor panel of claim 11, wherein said coupling parts are made such that they can be turned in and/or out one another by means of a movement of rotation.

17. The floor panel of claim 11, wherein said board is fiberboard of the type MDF or HDF.

18. The floor panel of claim 17, wherein said decorative layer is selected from the group consisting of: a printed paper layer, a layer of wood, a veneer layer and a cork layer.

19. The floor panel of claim 11, wherein said decorative layer is selected from the group consisting of: a layer of wood, a veneer layer and a cork layer.

20. The floor panel of claim 11, wherein the floor panel is rectangular, said floor panel comprising a first pair of opposite edges, formed by the aforementioned two opposite edges, and a second pair of opposite edges, which is also provided with coupling parts at least offering a locking in the horizontal direction.

21. A floor panel for forming a floor covering, wherein the floor panel is a laminate panel made of a board on the basis of wood, upon which one or several layers, including a decorative layer, are provided; wherein the floor panel is provided on at least two opposite edges with coupling parts made in one piece with the floor panel, as a result of which two of such floor panels can be mutually coupled to one another; wherein said coupling parts, in a coupled situation, provide for an interlocking in a direction perpendicular to a 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; wherein said coupling parts comprise a tongue and a groove, said groove being bordered by an upper lip and a lower lip, the distal end of the upper lip defining a vertical plane that forms a closing plane between two of such coupled floor panels, said lower lip extending further than said vertical plane; wherein said coupling parts comprise first cooperating surfaces, on the top side of the tongue and the bottom side of the upper lip respectively, said first cooperating surfaces, in the coupled situation, working in conjunction with one another and forming a first cooperating zone, and second cooperating surfaces, on an interlocking part that is situated on the lower lip and on an opposite part of the other floor panel respectively, said second cooperating surfaces, in the coupled situation, working in conjunction with one another and forming a second cooperating zone; wherein said coupling parts are made such that two of such floor panels can be assembled by pushing towards one another by means of a movement mainly parallel to the plane of the floor covering; wherein the distal tip of said tongue, in the coupled situation, is situated in said groove past said vertical plane; wherein a distance between said vertical plane and the distal end of the lower lip is smaller than a thickness of the floor panel; and wherein an intersection between a second vertical plane defined by the most outwardly situated point of said first cooperating zone and the bottom side of the tongue is situated beneath a horizontal level defined by the uppermost point of the top side of said interlocking part.

22. The floor panel of claim 21, wherein the lowermost point of the bottom side of the tongue defines a second horizontal level; wherein said first and second horizontal level define a third horizontal level situated right in between; and wherein the intersection between said second vertical plane and the bottom side of the tongue is situated beneath said third horizontal level.

23. The floor panel of claim 21, wherein the tongue and the groove are made such that when two of such floor panels are freely pushed towards one another, over a base or such, the tongue automatically ends up in the groove.

24. The floor panel of claim 21, wherein said interlocking part is situated on a part of the lower lip that is situated past said vertical plane.

25. The floor panel of claim 21, wherein said cooperating surfaces forming the second cooperating zone, or their tangent line, are directed slantingly in relation to the plane of the floor covering.

26. The floor panel of claim 21, wherein said coupling parts are made such that they can be turned in and/or out one another by means of a movement of rotation.

27. The floor panel of claim 21, wherein said board is fiberboard of the type MDF or HDF.

28. The floor panel of claim 27, wherein said decorative layer is selected from the group consisting of: a printed paper layer, a layer of wood, a veneer layer and a cork layer.

29. The floor panel of claim 21, wherein said decorative layer is selected from the group consisting of: a layer of wood, a veneer layer and a cork layer.

30. The floor panel of claim 21, wherein the floor panel is rectangular, said floor panel comprising a first pair of opposite edges, formed by the aforementioned two opposite edges, and a second pair of opposite edges, which is also provided with coupling parts at least offering a locking in the horizontal direction.

Description

DESCRIPTION OF THE DRAWINGS

(1) 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:

(2) FIG. 1 schematically represents a hard flooring panel;

(3) FIG. 2 schematically represents a part of a floor covering made of hard panels shown in FIG. 1;

(4) FIG. 3 represents an embodiment of coupling means of coupled panels according to the invention applied in a floor covering, seen from a section which corresponds for example to section in FIG. 2;

(5) FIG. 4 represents a section according to prior art viewed along line IV-IV in FIG. 2;

(6) FIG. 5 represents a variant of FIG. 4;

(7) FIGS. 6 to 8 represent the coupling means from FIG. 3 in different positions;

(8) FIG. 9 represents a variant of the coupling means from FIG. 3;

(9) FIG. 10 represents another variant;

(10) FIGS. 11 to 13 represent the variant from FIG. 10 in different positions;

(11) FIG. 14 represents another variant;

(12) FIG. 15 represents yet another variant;

(13) FIGS. 16 and 17 represent the coupling means of FIG. 15 in two other positions;

(14) FIG. 18 represents an angular part of a panel according to the invention;

(15) FIG. 19 represents a section of another embodiment according to the invention;

(16) FIG. 20 represents a section of another embodiment of a floor covering made of panels according to the invention;

(17) FIG. 21 represents the part indicated by F21 in FIG. 20 on a larger scale;

(18) FIG. 22 represents how the panels of the floor covering from FIG. 20 can be disconnected and connected respectively;

(19) FIG. 23 represents the part indicated by F23 in FIG. 22 on a larger scale;

(20) FIG. 24 represents a view analogous to that in FIG. 21 for another variant;

(21) FIG. 25 represents how the panels of FIG. 24 can be mutually disconnected and connected respectively;

(22) FIG. 26 represents the part indicated by F26 in FIG. 25 on a larger scale.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

(23) As represented in FIGS. 1 and 2, the invention concerns hard floor covering panels 2 from which a floor covering 1 may be formed by coupling of the panels.

(24) As described in U.S. Pat. No. 6,006,486, 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.

(25) Coupling means can be used which allow for different coupling methods, but preferably coupling by rotating the panels relative to each other as well as by pushing the panels together while in a generally common plane. 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 FIG. 2 with a movement of rotation W1, and by subsequently snapping them together on their edges 5-6 by means of a translation motion 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 coupling the panel 2 concerned by means of a translation T2.

(26) 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.

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

(28) FIG. 3 represents an embodiment according to a first aspect of the invention.

(29) Also, in this embodiment, the floor covering 1 comprises 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.

(30) 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 upper lip 10, in other words, which extends further than the distal end 12 of the lip 10 in the horizontal direction away from groove 9.

(31) 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.

(32) According to the invention, the panel edge 5 which is provided with the tongue 8 is made elastically flexible, whereas the lip 11 is preferably made rigid, the latter by making it relatively thick, as is clearly visible in FIG. 3.

(33) The panel edge 5 is made such that it can elastically bend in several places. Thus, for example, the tongue 8 is flexible, but even more important is that this tongue 8 is preferably 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 or reduced cross-section.

(34) This flexible zone 17 is preferably situated on the place as indicated in FIG. 3, 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 and/or smaller than of the thickness D2 of the part 16 upon which the tongue 8 is situated.

(35) 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.

(36) 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.

(37) Apart from the advantages already mentioned in the introduction, the invention according to the first aspect also offers the following advantageous characteristics: 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 B1 and B2 represented in FIG. 3. Thus is obtained a solid interlocking. 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. In the design of FIG. 3 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.

(38) According to a second aspect of the invention, which in the given example of FIG. 3 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.

(39) 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.

(40) According to the embodiment of FIG. 3, there is a free space 23 under the tongue 8 which extends from the tip 24 of the tongue 8 up to the third coupling parts, in other words the contact surface 14.

(41) 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 FIG. 4 or FIG. 5, which are described in U.S. Pat. No. 6,006,486 and which make it possible for the panels 2 concerned to be assembled along their top edges and, disassembled, respectively at least by means of a movement of relative 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.

(42) The above-described arrangement does not exclude, however, that the coupling means 7 may be 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.

(43) 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.

(44) 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 FIGS. 6 to 8, 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 relative rotation, and disconnected, respectively, as is represented by means of a dot and dash line in FIG. 3.

(45) 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 FIG. 2, 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 FIG. 4, or, as an alternative, FIG. 5, is created.

(46) Then, the panel 2A can be connected to the preceding panel with a translation T1, whereby the situations as represented in FIGS. 6 to 8 are successively observed on the coupling means 7. It is clear that this is accompanied by an elastic 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.

(47) FIG. 9 represents an embodiment which is realized according to the above-mentioned third aspect of the invention. 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 in this example, 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.

(48) As represented in FIG. 9, a bulge or protrusion 30 can be provided in the lower lip 11 on the contact zone 29.

(49) FIGS. 10 to 13 represent an embodiment for different positions with coupling means 31 which are in conformity with a fourth aspect of the invention. The upper lip 10 is hereby longer than the lower lip 11, and the coupling means 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.

(50) 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 FIGS. 10 to 12.

(51) As shown in the figures, the tongue 8 has one end 24 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.

(52) The embodiment of FIGS. 10 to 13 also illustrates a fifth aspect of the invention, 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 towards their bottom sides 38 and towards one another, as is specifically shown in FIG. 13. The above-mentioned space 35 is helpful thereby.

(53) The embodiment of FIGS. 10 to 13 also corresponds to a sixth aspect of the invention, wherein 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.

(54) FIG. 14 represents a variant which also applies the above-mentioned characteristics of the sixth aspect of the invention.

(55) 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 as well as rotational movement about the coupled edge.

(56) As seen in FIG. 14, the groove 9 has an innermost point 9a. The recess 41 is located within the portion of the groove 9 which is located between the innermost point 9a of the groove and the distal end 36 of the lower lip 11. It will also be evident that the bottom side of the tongue 8 at least in the region of the tongue located directly underneath the protrusion 39 and underneath the portion of the top side of the tongue extending from the protrusion 41 to the distal end 8a of the tongue is free from horizontally active coupling parts. It will also be evident from FIG. 14 that the protrusion 41 is located at a distance proximally inwardly from an imaginary vertical transverse plane intersecting the distal tip 8a of the tongue 8. A portion 40a of the top side of the tongue 8 extends generally parallel with the plane of the floor panel and forms a contact surface cooperating with the lower side of the upper lip 10.

(57) FIG. 15 represents a connection with coupling means 43 realized according to a seventh aspect of the invention. It concerns a connection whereby: the coupling means 43 comprise a tongue 8 and a groove 9, whereby this groove 9 is bordered on the bottom and top sides, respectively, by a lip, hereafter called the lower lip 11 and the upper lip 10, respectively, wherein the distal end 12 of the upper lip 10 defines (i.e., intersects) a vertical plane, hereafter called plane V1; the lower lip 11 is longer than the upper lip 10; 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 intersects a vertical plane, hereafter called plane V2; 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; 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 intersects a first vertical plane, hereafter called plane V3, the most outwardly situated point C4 of this contact zone intersects 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; the top side of the interlocking part 13 defines a horizontal level, hereafter called level N1; 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; the levels N1 and N2 define a horizontal level situated right in between, hereafter called level N3; 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; the distance between the planes V1 and V2 is at least half of the distance between the levels N3 and N4.

(58) This floor covering 1 is special in that it provides at least the combination of the following characteristics: that the panels 2, and basically also the above-mentioned lips 10-11, are made of fiberboard of the type MDF or HDF; that the coupling means 43 are made such that the panels 2 can be assembled by pushing them towards one another; and 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: that the part of this space 44 which is situated under the level N3 extends inwardly to at least past the plane V1; that the part of this space 44 which is situated under the level N1 extends inwardly to at least past the plane V5.

(59) Thanks to this specific combination there is obtained a space 44 which acts as a depression 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 depression 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.

(60) The distance between the levels N1 and N2 is preferably smaller than 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.

(61) 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 possible 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.

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

(63) According to a preferred characteristic of the invention, the part of the above-mentioned space 44 situated under the plane N3 would extend at least inwardly up to the vertical plane V6 which is determined by the tip 24 of the tongue 8.

(64) 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 10, at least the above-mentioned space 44 is preferably made continuous up to the end of the panel 2, as represented in FIG. 18, in the corner 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.

(65) FIG. 19 illustrates an eighth aspect of the invention, whereby a depression 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 FIG. 19, the tongue 8 is better positioned in front of the groove.

(66) 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.

(67) 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 FIG. 3, 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.

(68) 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.

(69) 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.

(70) The coupling means which are realized according to one or several of the first eight aspects of the invention 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.

(71) 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.

(72) 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.

(73) FIGS. 20 to 23 show an embodiment according to a ninth aspect of the invention. According to this ninth aspect, it concerns floor covering hard panels 2, wherein 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 to form floor covering 1, whereby these coupling means 7 provide for an interlocking in a direction R1, perpendicular to the plane of the coupled panels, as well as in a direction R2 perpendicular to the edges 3-4 concerned and parallel to the plane of the coupled panels, whereby the above-mentioned coupling means 7 are made such that two connected panels 2 can be turned about their coupled edges towards one another toward 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.

(74) Moreover, according to the embodiment of FIGS. 20 to 23, the coupling means 7 are made such that, as represented in FIG. 22, they make it possible for the two panels 2 to be lifted along 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 FIG. 22 up, as represented by means of a dot and dash line, so that the left panel 2 of FIG. 22 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.

(75) FIGS. 20 to 26 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, along 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.

(76) Both in the embodiment of FIGS. 20 to 23 and in the one of FIGS. 24 to 26, 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.

(77) 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 FIG. 21, 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.

(78) In the embodiment of FIGS. 24 to 26, 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 FIG. 26, comes loose so to say and can simply be removed from the left panel 2.

(79) 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.

(80) It should be noted that in the embodiments of FIGS. 20 to 26, 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 FIGS. 20 to 23, or because it is relatively short, as represented in FIGS. 24 to 26.

(81) 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 with regard to FIGS. 20 to 26. 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 FIG. 4.

(82) The invention is by no means limited to the above-described embodiments represented in the accompanying drawings; on the contrary, such a floor covering can be made in different shapes and dimensions while still remaining within the scope of the invention.