SET OF FLOOR PANELS FOR FORMING A FLOOR COVERING

Abstract

A set of floor panels for forming a floor covering, which comprises at least two floor panels, which each comprise an edge provided with a coupling part, wherein the coupling parts are configured such that they allow realizing a coupled condition between the floor panels, by means of a substantially straight-lined coupling movement of the one floor panel in respect to the other floor panel, according to a direction substantially perpendicular to an installation plane; and wherein the coupling parts are configured such that they, in the coupled condition, realize a tensioning force pressing the coupled edges towards each other.

Claims

1. A set of floor panels for forming a floor covering, which comprises at least two floor panels, which each comprise an upper side, a lower side, and a core extending between the upper and lower sides, and which each comprise an edge provided with a coupling part and the core extending from the edge to an opposite edge to said edge, wherein the coupling parts are configured such that they allow realizing a coupled condition between the floor panels by means of a substantially straight coupling movement of the one floor panel in respect to the other floor panel, according to a direction substantially perpendicular to an installation plane; wherein the coupling parts in the coupled condition effect a locking in the direction parallel to the installation plane and perpendicular to said edges, as well as a locking in the direction perpendicular to the installation plane; wherein the coupling part of the one floor panel is made as a hook-shaped part directed towards the lower side of the floor panel, herein below denominated locking hook, and the coupling part of the other floor panel is made as a hook-shaped part directed towards the upper side of the floor panel, herein below denominated receiving hook; wherein the hook-shaped parts are manufactured from the material of the core of the floor panels and are made in one piece therewith; wherein the locking hook comprises a lip which is provided with a locking part extending towards the lower side of the floor panel, and the receiving hook comprises a lip which is provided with a locking part extending towards the upper side of the floor panel; wherein the locking parts, in the coupled condition, cooperate in such a manner that they effect at least the aforementioned locking in the direction parallel to the installation plane and perpendicular to said edges; wherein the coupling parts are configured such that they, in the coupled condition, realize a tensioning force pressing the coupled edges towards each other, by means of an elastic bending of the lip of the receiving hook; and wherein the lip of the receiving hook, in the coupled condition, in the direction perpendicular to the installation plane, has a maximum bending of at most 0.0625 times the overall thickness of the floor panel; wherein the locking in the direction perpendicular to the installation plane, at the edges to which the hook-shaped parts belong, is effected by means of locking elements, of which at least one locking element is made as a separate insert from the one and other floor panel.

2. The set of floor panels of claim 1, wherein the insert is provided in a groove present in a distal side of the locking hook.

3. The set of floor panels of claim 1, wherein the insert has an attachment part provided in a groove in the edge of the panel, the insert also having a movable part connected to the attachment part by a connection part and arranged to elastically move relative to the attachment part and into a groove defined by a side of the other floor panel.

4. The set of floor panels of claim 1, wherein the elastic bending of the lip of the receiving hook can be initiated by a mutual interaction of proximal sides, including locking surfaces of the locking parts.

5. The set of floor panels of claim 1, wherein the lip of the receiving hook comprises a bridge part connected to the core of the floor panel, and an end part connected to the bridge part, to which end part the locking part extending towards the upper side of the floor panel is pertaining, wherein the bridge part comprises an upper side provided with a recess or groove, which recess, viewed according to the direction parallel to the upper or lower side of the floor panel and perpendicular to the edge, is situated at a first distance from there, where the bridge part is connected to the core of the floor panel, and at a second distance from there, where the bridge part is connected to the end part.

6. The set of floor panels of claim 5, wherein the lip of the receiving hook shows its minimum thickness there, where said recess is provided.

7. The set of floor panels of claim 5, wherein the bridge part, there, where it is connected to the core of the floor panel, and there, where it is connected to the end part, is made more rigid or thicker than there, where said recess is provided.

8. The set of floor panels of claim 5, wherein the bridge part comprises one or more of the following characteristics: there, where the bridge part is connected to the core of the floor panel, it has a thickness which is at least ⅕ times the overall thickness of the floor panel; and/or there, where the bridge part is connected to the end part, it has a thickness which is at least ⅕ times the overall thickness of the floor panel.

9. The set of floor panels of claim 1, wherein the coupling parts are configured such that they allow uncoupling the floor panels, starting from the coupled condition, by means of a rotational movement of the one floor panel around the other floor panel, around an axis parallel to the installation plane and the edges, wherein during said rotational movement the upper sides of the floor panels are moved towards each other.

10. The set of floor panels of claim 1, wherein each of the floor panels comprises an edge adjacent to its aforementioned edge, herein below denominated adjacent edge, which is provided with a coupling part, wherein the coupling parts at the adjacent edges are configured such that they allow realizing a coupled condition between the floor panels, wherein the coupling parts at the adjacent edges, in the coupled condition, effect a locking in the direction parallel to the installation plane and perpendicular to the adjacent edges, as well as a locking in the direction perpendicular to the installation plane, and wherein the coupling parts at the adjacent edges are configured such that they, in the coupled condition, realize a tensioning force pressing the adjacent coupled edges towards each other, by means of an elastic bending of a lip pertaining to the coupling parts of the adjacent edges; and wherein, in the coupled condition of a plurality of the floor panels, the average degree of bending of the lip of the receiving hook, viewed over a length of the coupled edges, differs from the average degree of bending of the lip pertaining to the coupling parts of the adjacent edges, viewed over a length of the coupled adjacent edges; wherein the coupling parts at the adjacent edges are realized as a tongue and a groove, wherein the groove is bordered by an upper lip and the aforementioned lip belonging to the coupling parts of the adjacent edges, herein below denominated lower lip; wherein the lower lip extends beyond the distal extremity of the upper lip; and wherein the tongue and the groove are provided with lock-up parts, which in the coupled condition effect said locking in the direction parallel to the installation plane and perpendicular to the adjacent edges; wherein the coupling parts at the adjacent edges are configured such that they allow realizing a coupled condition between the floor panels, by means of a rotational movement of the one floor panel in respect to the other floor panel, according to a direction parallel to the installation plane and the adjacent edges, in such a manner that a plurality of the floor panels can be coupled by means of a fold-down movement.

11. The set of floor panels of claim 10, wherein the average degree of bending of the lip of the receiving hook is larger than the average degree of bending of the lip pertaining to the coupling parts of the adjacent edges.

12. The set of floor panels of claim 1, wherein the lip of the receiving hook comprises a bridge part connected to the core of the floor panel and an end part connected to the bridge part to which the locking part extending towards the upper side of the floor panel pertains and wherein the bridge part comprises an upper side provided with a recess and has a first and second thickness at respective opposed sides of the recess being larger than a third thickness of the bridge part at the recess.

13. The set of floor panels of claim 1, wherein said maximum bending is at most 0.05 times the overall thickness of the floor panel.

14. The set of floor panels of claim 1, wherein the elastic bending relates to a downward bending, wherein the lip of the receiving hook partially is situated lower than a level defined by the lower side of the floor panel to which the locking hook is belonging; wherein the elastic bending in distal direction in respect to the receiving hook relates to a continuously increasing bending, wherein said maximum bending occurs at the distal end of the lip of the receiving hook; and wherein the lip of the receiving hook is bent at least over 25% of the length thereof.

15. A set of floor panels for forming a floor covering, which comprises at least two floor panels, which each comprise an upper side, a lower side, and a core extending between the upper and lower sides, and which each comprise an edge provided with a coupling part and the core extending from the edge to an opposite edge to said edge, wherein the coupling parts are configured such that they allow realizing a coupled condition between the floor panels by means of a substantially straight coupling movement of the one floor panel in respect to the other floor panel, according to a direction substantially perpendicular to an installation plane; wherein the coupling parts in the coupled condition effect a locking in the direction parallel to the installation plane and perpendicular to said edges, as well as a locking in the direction perpendicular to the installation plane; wherein the coupling part of the one floor panel is made as a hook-shaped part directed towards the lower side of the floor panel, herein below denominated locking hook, and the coupling part of the other floor panel is made as a hook-shaped part directed towards the upper side of the floor panel, herein below denominated receiving hook; wherein the hook-shaped parts are manufactured from the material of the core of the floor panels and are made in one piece therewith; wherein the locking hook comprises a lip which is provided with a locking part extending towards the lower side of the floor panel, and the receiving hook comprises a lip which is provided with a locking part extending towards the upper side of the floor panel; wherein the locking parts, in the coupled condition, cooperate in such a manner that they effect at least the aforementioned locking in the direction parallel to the installation plane and perpendicular to said edges; wherein the coupling parts are configured such that they, in the coupled condition, realize a tensioning force pressing the coupled edges towards each other, by means of an elastic bending of the lip of the receiving hook; and wherein the coupling parts are configured such that at least a portion of the locking part extending towards the lower side of the floor panel fits into an opening defined between the locking part extending towards the upper side of the floor panel and a proximal side of the receiving hook, without having to elastically bend the lip of the receiving hook for this purpose; wherein the locking in the direction perpendicular to the installation plane, at the edges to which the hook-shaped parts belong, is effected by means of locking elements, of which at least one locking element is made as a separate insert from the one and other floor panel; wherein the elastic bending of the lip of the receiving hook can be initiated by a mutual interaction of proximal sides, including locking surfaces of the locking parts.

16. The set of floor panels of claim 15, wherein the elastic bending of the lip of the receiving hook can be initiated from an already partially engaged condition of the hook-shaped parts.

17. The set of floor panels of claim 15, wherein the lip of the receiving hook comprises a bridge part connected to the core of the floor panel, and an end part connected to the bridge part, to which end part the locking part extending towards the upper side of the floor panel is pertaining, wherein the bridge part comprises an upper side provided with a recess or groove, which recess, viewed according to the direction parallel to the upper or lower side of the floor panel and perpendicular to the edge, is situated at a first distance from there, where the bridge part is connected to the core of the floor panel, and at a second distance from there, where the bridge part is connected to the end part; wherein the lip of the receiving hook shows its minimum thickness there, where said recess is provided; wherein the bridge part, there, where it is connected to the core of the floor panel, and there, where it is connected to the end part, is made more rigid or thicker than there, where said recess is provided.

18. A set of floor panels for forming a floor covering, which comprises at least two floor panels, which each comprise an upper side, a lower side, and a core extending between the upper and lower sides, and which each comprise an edge provided with a coupling part and the core extending from the edge to an opposite edge to said edge, wherein the coupling parts are configured such that they allow realizing a coupled condition between the floor panels by means of a substantially straight coupling movement of the one floor panel in respect to the other floor panel, according to a direction substantially perpendicular to an installation plane; wherein the coupling parts in the coupled condition effect a locking in the direction parallel to the installation plane and perpendicular to said edges, as well as a locking in the direction perpendicular to the installation plane; wherein the coupling part of the one floor panel is made as a hook-shaped part directed towards the lower side of the floor panel, herein below denominated locking hook, and the coupling part of the other floor panel is made as a hook-shaped part directed towards the upper side of the floor panel, herein below denominated receiving hook; wherein the hook-shaped parts are manufactured from the material of the core of the floor panels and are made in one piece therewith; wherein the locking hook comprises a lip which is provided with a locking part extending towards the lower side of the floor panel, and the receiving hook comprises a lip which is provided with a locking part extending towards the upper side of the floor panel; wherein the locking parts, in the coupled condition, cooperate in such a manner that they effect at least the aforementioned locking in the direction parallel to the installation plane and perpendicular to said edges; wherein the coupling parts are configured such that they, in the coupled condition, realize a tensioning force pressing the coupled edges towards each other, by means of an elastic bending of the lip of the receiving hook; wherein the lip of the receiving hook has a minimum thickness, which is at least ⅕ times and at most ⅓ times the overall thickness of the floor panel; and wherein a length of the lip of the receiving hook, measured between a vertical closing surface and the distal end of the lip of the receiving hook, is at least 1 time and at most 3/2 times the overall thickness of the floor panel; wherein the locking in the direction perpendicular to the installation plane, at the edges to which the hook-shaped parts belong, is effected by means of locking elements, of which at least one locking element is made as a separate insert from the one and other floor panel.

19. The set of floor panels of claim 18, wherein said minimum thickness is at most 0.3 times the overall thickness of the floor panel; and wherein said length is at most 1.4 times the overall thickness of the floor panel.

20. The set of floor panels of claim 18, wherein the lip of the receiving hook comprises a bridge part connected to the core of the floor panel, and an end part connected to the bridge part, to which end part the locking part extending towards the upper side of the floor panel is pertaining, wherein the bridge part comprises an upper side provided with a recess or groove, which recess, viewed according to the direction parallel to the upper or lower side of the floor panel and perpendicular to the edge, is situated at a first distance from there, where the bridge part is connected to the core of the floor panel, and at a second distance from there, where the bridge part is connected to the end part; wherein the lip of the receiving hook shows its minimum thickness there, where said recess is provided; wherein the bridge part, there, where it is connected to the core of the floor panel, and there, where it is connected to the end part, is made more rigid or thicker than there, where said recess is provided.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0071] With the intention of better showing the characteristics of the invention, herein below, as an example without any limitative character, some preferred embodiments are described, with reference to the accompanying drawings, wherein:

[0072] FIG. 1 in top view represents a set of oblong rectangular floor panels, wherein the floor panels are in a not-coupled or not-installed condition;

[0073] FIG. 2 represents a cross-section according to line II-II in FIG. 1;

[0074] FIG. 3 represents a cross-section according to line III-III in FIG. 1;

[0075] FIG. 4 represents how a plurality of the floor panels of FIG. 1 can be coupled to each other;

[0076] FIG. 5, in an enlarged view, represents the edges from FIG. 2, however, in the coupled condition of the floor panels;

[0077] FIG. 6 represents a step in the coupling movement of the edges at the short sides of the floor panels from FIG. 1;

[0078] FIG. 7 represents how the floor panels from FIG. 1 can be uncoupled at the edges of their short sides by means of a pivoting movement; and

[0079] FIGS. 8 through 11 represent alternatives to the embodiment of the edges of the short sides of the floor panels from FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0080] FIG. 1, in top view, represents a set of floor panels 1A-1B for forming a floor covering, wherein the floor panels 1A-1B here are oblong rectangular and thus comprise a pair of short sides and a pair of long sides. The floor panels 1A-1B are represented in a not-coupled or not-installed condition.

[0081] The opposite short sides of the floor panels 1A-1B form edges 2-3 which are provided with coupling parts 4-5. Although here opposite edges 2-3 of two floor panels 1A-1B are concerned, it is clear that these edges 2-3 can also relate to edges of one and the same floor panel, which then relate to opposite edges of that floor panel.

[0082] The long sides of the floor panels 1A-1B form edges 6-7, which are provided with coupling parts 8-9.

[0083] FIG. 2 represents a cross-section according to line II-II in FIG. 1. Thus, FIG. 2 represents a cross-section wherein the coupling parts 4-5 on the short sides of the floor panels 1A-1B are visible.

[0084] The floor panels 1A-1B each comprise an upper side 10, a lower side 11, and a core 12 extending between the upper and lower sides 10-11.

[0085] The floor panels 1A-1B relate to decorative floor panels, which comprise a top layer 43, wherein the top layer comprises at least a decor and a transparent wear layer.

[0086] The coupling part 4 of the one floor panel 1A is realized as a hook-shaped part 13 directed towards the lower side 11 of the floor panel 1A, herein below denominated looking hook 13.

[0087] The coupling part 5 of the other floor panel 1B is realized as a hook-shaped part 14 directed towards the upper side 10 of the floor panel 1B, herein below denominated receiving hook 14.

[0088] The hook-shaped parts 13-14 substantially are made from the material of the core 12 of the floor panels 1A-1B and substantially are made in one piece therewith. Here, the hook-shaped parts 13-14 even are made entirely from the material of the core 12, and in one piece therewith, with the exception of the insertion piece 19. To this aim, the hook-shaped parts 13-14 can be manufactured, for example, from the material of the core 12 by means of milling treatments, which is an economically advantageous and efficient manner of manufacturing the hook-shaped parts 13-14.

[0089] The locking hook 13 comprises a lip 15 which is provided with a locking part 16 extending towards the lower side 11 of the floor panel 1A.

[0090] The receiving hook 14 comprises a lip 17 which is provided with a locking part 18 extending towards the upper side 10 of the floor panel 1B.

[0091] As illustrated by means of the coupling part 4 represented in dotted line, the coupling parts 4-5 are configured such that they allow realizing a coupled condition between the floor panels 1A-1B, by means of a substantially straight coupling movement M of the one floor panel 1A in respect to the other floor panel 1B, according to a direction substantially perpendicular to an installation plane.

[0092] More particularly, the coupling parts 4-5 here are configured such that they also allow realizing a coupled condition between the floor panels 1A-1B, by means of a rotational movement of the one floor panel 1A in respect to the other floor panel 1B, around an axis parallel to the installation plane and perpendicular to the edges 2-3, in order to be able to perform the fold-down movement, which will be described in greater detail in respect to FIG. 4.

[0093] In the coupled condition of the floor panels 1A-1B, which is illustrated in greater detail in FIG. 5, the coupling parts 4-5 effect a locking in the direction H parallel to the installation plane and perpendicular to the aforementioned edges 2-3, as well as a locking in the direction V perpendicular to the installation plane.

[0094] Here, the locking parts 16 and 18 perform the locking in the direction H parallel to the installation plane and perpendicular to the aforementioned edges 2-3.

[0095] The locking in the direction V perpendicular to the installation plane is effected by means of locking elements 19-20. The locking element 19 here is realized as a separate insertion piece or insert, as known as such from, for example, the herein above-mentioned WO '804.

[0096] The insert 19 here is provided in a groove 26, which is present in a distal side 21 of the locking hook 13. This offers the advantage that such groove 26 does not have to be provided in the receiving hook 14, which then as a result thereof can be made strong and can render sufficient stability to the lip 17.

[0097] However, it is not excluded that such insert 19 is provided in a groove which is present in a proximal side 23 of the receiving hook 14, which then preferably, instead of an upward-directed part 27, comprises a downward-directed part.

[0098] The part 27 is elastically movable, for example, by elastic bending and/or compression, and during the coupling movement performs a lateral movement, illustrated in greater detail in FIG. 6.

[0099] It is clear that here, and also in general, by the term “lateral movement” a sideward movement is meant which has at least a movement component in the direction parallel to the installation plane and perpendicular to the edges 2-3.

[0100] It should be noted that the part 27 here primarily, starting from a relaxed or initial condition, will perform a movement in the direction towards the floor panel 1A, after which the part 27 subsequently will at least partially relaxate towards a locking condition and herein will move in the direction towards the floor panel 1B.

[0101] In the locking condition, the part 27 works in conjunction with the locking element 20 at the other floor panel 20, shown in more detail in FIG. 5. Preferably, the part 27 relaxates only partially, as a result of which it is at least partially tensioned in the locking condition and realizes a tensioning force.

[0102] The insert 19 here is provided in the groove 26 by means of an attachment part 28, which can be clamped in this groove 26, for example, in that the part 28 is made not precisely fitting with the groove 26.

[0103] Here, the attachment part 28 more particularly is connected to the movable part 27 by means of a connection part 29.

[0104] More particularly, the insert 19 here is made as a coextruded strip, wherein the connection part 29 is manufactured of a softer or more elastic material than the material of the parts 27 and 28, which principle is known as such from, for example, the herein above-mentioned WO '153.

[0105] The lip 17 of the receiving hook 14 comprises a bridge part 37 connected to the core 12 of the floor panel 1B, and an end part 38 connected to the bridge part 37, to which end part the locking part 18 extending towards the upper side of the floor panel is belonging.

[0106] The bridge part 37 comprises an upper side provided with a recess 39. The recess 39, viewed according to the direction parallel to the upper or lower side 10-11 of the floor panel 1B and perpendicular to the edge 3, is situated at a distance from there, where the bridge part 37 is connected to the core 12 of the floor panel 1B, and from there, where the bridge part 37 is connected to the end part 38.

[0107] There, where the recess 39 is provided, the lip 17 has its minimum thickness D1, which preferably is at least ⅕ times and at most ⅓ times the overall thickness of the floor panel 1B. More particularly, the minimum thickness D1 here is at most ¼ times the overall thickness T of the floor panel 1B.

[0108] There, where the bridge part 37 is connected to the core 12 of the floor panel 1B and there, where it is connected to the end part 38, it is made more rigid or thicker than there, where the aforementioned recess 39 is provided.

[0109] There, where the bridge part 37 is connected to the core 12, said bridge part has a thickness D2 which is at least ⅕ times and preferably at least ¼ times the overall thickness T of the floor panel 1B.

[0110] There, where the bridge part 37 is connected to the end part 38, said bridge part has a thickness D3 which is at least ⅕ times and preferably at least ¼ times the overall thickness T of the floor panel 1B.

[0111] That the bridge part 37 is made more rigid or thicker in the specific zones offers the advantage that the lip 17 is strong and can withstand possible loads which it is subjected to, in particular in the zones. Moreover, the additional advantage is obtained that, in that the bridge part 37 there, where it is connected to the end part 38, is made thicker, the locking surface 42 can be lifted, i.e. can be brought towards a higher or more upward position, which promotes the smooth pivoting apart of the floor panels, illustrated in more detail in FIG. 7.

[0112] The length L of the lip 17, measured between the vertical closing surface VS and the distal end of the lip 17, is at least 1 time and at most 3/2 times the overall thickness T of the floor panel 1B. In particular, the length L here is at most 4/3 times the overall thickness T of the floor panel 1B.

[0113] The lip 17 of the receiving hook 14 comprises a lower side which is free from recesses or grooves, or weakened parts in general.

[0114] The locking part 18 defines a point P situated most towards the upper side 10 of the floor panel 1B, which point is located in the lower half of the floor panel 1B. Such rather low designed locking part 18, amongst others, offers the advantage that the pivoting apart of the floor panels 1A-1B, illustrated in greater detail in FIG. 7, can be performed in a smooth manner.

[0115] FIG. 3 represents a cross-section according to line III-III in FIG. 1. Thus, here a cross-section is represented wherein the coupling parts 8-9 on the long sides of the floor panels 1B are visible.

[0116] More particularly, the coupling parts 8-9 are realized as a tongue 30 and a groove 31, respectively, wherein the groove 31 is bordered by an upper lip 32 and a lower lip 33, which lower lip 33 extends beyond the distal end of the upper lip 32. The tongue 30 and the groove 31 are provided with lock-up parts 34-35. In the coupled condition, they effect the locking in the direction parallel to the installation plane and perpendicular to the edges 6-7.

[0117] As illustrated by the coupling part 8 represented in dotted line, the coupling parts 8-9 are configured such that they allow realizing the coupled condition between the floor panels 1A-1B, by means of a rotational movement W of the one floor panel 1A in respect to the other floor panel 1B, according to a direction parallel to the installation plane and the edges 6-7.

[0118] Locking tongue and groove connections, such as those described herein above in respect to FIG. 3, are known as such, amongst others, from the already mentioned herein above WO '834. From that document, it is known that such tongue and groove connections can be provided with pretension, i.e., that they, in the coupled condition, realize a tensioning force pressing the coupled edges towards each other, for example, by means of an elastic bending of the lower lip. Herein, it is noted that with such locking tongue and groove connections the pretension poses less difficulties in respect to the smoothness of installation, as they are coupled by means of a pivoting or rotational movement, as described herein above.

[0119] FIG. 4 represents how a plurality of the floor panels of FIG. 1 can be coupled by means of the so-called fold-down movement F, which as such is known, amongst others, from WO 01/75247 A1 and, already mentioned herein above, WO '153.

[0120] As illustrated, the floor panel 1A is coupled at its long side to an already installed floor panel 1C from a preceding row, by means of a pivoting movement, and at the same time is coupled at its short side to an already installed floor panel 1B from the same row, by means of the same pivoting movement, which is also called a scissor movement.

[0121] It is noted that the fold-down movement in practice mostly is preceded by a shifting movement of the floor panel 1A in respect to the floor panel 1C, along the long sides of these floor panels 1A and 1C, wherein the tongue during this shifting movement already is partially introduced into the groove. Herein, the floor panel 1A is in an inclined condition.

[0122] The floor panels 1A-1B-1C here are represented as perfectly rectangular floor panels, i.e. the short sides are perpendicular to the long sides. However, in practice this is not always the case. The standard EN 13329 namely allows a deviation from perpendicularity of 0.2 mm over the length of the side. It is clear that, due to this allowed deviation, performing the fold-down movement can be impeded; certainly at the sides where the coupling parts are realized in the form of hooks, here, thus, at the short sides, as these hooks due to the non-perpendicularity are difficult to engage into each other, certainly in the case of hooks made overlapping, which is the case with pretension.

[0123] Now, the inventor has found that the smoothness of installation still can be guaranteed by means of the herein above-described measures and the characteristics explained herein below in greater detail by means of FIGS. 5 and 6.

[0124] FIG. 5 in an enlarged view represents the edges 2-3 from FIG. 2, however, in the coupled condition of the floor panels 1A-1B.

[0125] As made visible, the coupling parts 4-5 are configured such that they, in coupled condition, realize a tensioning force pressing the coupled edges 2-3 towards each other, by means of an elastic bending of the lip 17 of the receiving hook 14.

[0126] Herein, the lip 17 has a maximum bending VM of at most 0.0625 times the overall thickness T of the floor panel 1B and this maximum bending here is specifically equal to approximately 0.0125 times the overall thickness of the floor panel 1B. The inventor has found that such maximum bending VM allows realizing an effective tensioning force which presses the coupled edges 2-3 towards each other, and that the smoothness of installation still can be guaranteed.

[0127] Herein, it is noted that the maximum bending VM of the lip 17 has to be understood as the maximum bending in respect to the resting condition of the lip 17, i.e. in respect to the condition of the lip 17 in not-coupled or not-installed condition of the floor panels 1A-1B, which is represented in FIG. 2.

[0128] Here, the bending of the lip 17 relates to a downward bending, wherein the lip 17 partially is situated lower than a level defined by the lower side 11 of the floor panel 1A to which the locking hook 13 is belonging.

[0129] Moreover, the bending relates to a bending continuously increasing in distal direction in respect to the receiving hook. By this is meant that the lip 17 is bent out more and more in distal direction, which in FIG. 5, for example, is represented by a more and more diminishing distance between the lower side of the lip 17 and the represented dotted line. The maximum bending VM then occurs at the distal end of the lip 17.

[0130] Such continuously increasing bending offers the advantage that the tension to which the lip 17 is subjected, can be spread over the length of this lip 17, and that an effective tensioning force can be realized without a noteworthy risk of breaking or damage of the lip 17.

[0131] Thus, the lip 17 preferably is bent over at least 25%, and still better over 50%, of its length.

[0132] As already described herein above, also the coupling parts 8-9 on the long edges 6-7 can be provided with pretension, wherein a tensioning force is created, which presses the coupled edges 6-7 towards each other, for example, by means of an elastic bending of the lower lip 33.

[0133] Herein, it is preferred that the average degree of bending of the lip 17 of the receiving hook 14, viewed over the length of the coupled edges 2-3, is different from, and preferably larger than, the average degree of bending of the lip 33 belonging to the coupling parts 8-9 of the adjacent edges 6-7, seen over the length of the coupled adjacent edges 6-7.

[0134] It is noted that by the length of the edges here the dimension of the edges in a direction parallel to these edges is meant.

[0135] That the bending of the lip 17 is larger than the bending of the lip 33, offers the advantage that a smooth installation can be guaranteed, whereas the formation of gaps on the coupled edges 2-3 and 6-7 can be counteracted in an optimum manner, certainly with oblong rectangular floor panels, such as those from FIG. 1.

[0136] On the one hand, it is advantageous that the bending of the lip 33 is relatively small, and smaller than the bending of the lip 17, as this allows smoothly performing the shifting movement of the floor panels 1A and 1C along their long sides, already described herein above, prior to the actual fold-down movement. On the other hand, it is advantageous to perform the bending of the lip 17 relatively large, and larger than the bending of the lip 33, as this results in a reduction of the risk of the penetration of moisture or dust at the short sides of the coupled floor panels 1A-1B.

[0137] As mentioned earlier in respect to FIG. 2, the movable part 27 of the insert 19 in the locking position can be partially tensioned, such that it realizes a tensioning force. This tensioning force provides for that the risk of height differences between the floor panels 1A-1B can be minimized or even excluded.

[0138] The tensioning force delivered by the part 27 here comprises at least a force component which pushes the coupled edges 2-3 out of each other, however, wherein this force component is smaller than the force component of the tensioning force delivered by the lip 17, which presses the coupled edges towards each other, such that the coupled edges 2-3 still are pressed towards each other.

[0139] At its distal side 22, the locking part 18 is free from locking elements. In the coupled condition, even a room or space 40 is formed between the distal side 22 and the opposite edge 2. This space 40 offers room for the elastic bending of the lip 17.

[0140] In the coupled condition, the locking surfaces 41-42 at the proximal sides 24-25 of the locking parts 16 and 18 cooperate such that they effect the locking in the direction H parallel to the installation plane and perpendicular to the edges 2-3. They are manufactured from the material of the core 12 of the floor panels 1A-1B and are made in one piece therewith.

[0141] The locking surface 42 extends in distal direction towards the upper side 10 of the floor panel 1B.

[0142] The locking surfaces 41-42 define a maximally inclined tangent line R, which forms an angle A of at most 85 degrees with a straight line parallel to the installation plane, wherein the tangent line R extends towards the upper side 10, in distal direction in respect to the receiving hook 14. Here, the angle A is equal to approximately 75 degrees.

[0143] The bridge part 37 also defines a support surface 45, which here more particularly is made horizontal. In the coupled condition of the floor panels 1A-1B, the locking part 16 rests on this support surface 45. The support surface also serves as a reference.

[0144] It is advantageous that this support surface 45 is situated in that zone of the bridge part 37 which is made rigid/thicker and moreover little or not at all experiences the elastic bending of the lip 17. So, this support surface 45, which also functions as a reference, always can be well defined.

[0145] FIG. 6 represents a step in the coupling movement of the edges 2-3 of the floor panels 1A-1B from FIG. 1.

[0146] As represented, the coupling parts 4-5 are configured such that at least a portion of the locking part 16 fits in an opening 36 defined between the locking part 18 and the proximal side 23 of the receiving hook 14, without having to elastically bend the lip 17 for this purpose.

[0147] In other words, the hook-shaped parts 13-14, in the step represented in FIG. 6, already are situated in a partially engaged condition of the hooks 13-14, without the lip 17 being elastically bent for this purpose. From this partially engaged condition, the elastic bending of the lip 17 then can be initiated, in particular by pressing the locking hook 13, from the position represented in FIG. 6, further downward.

[0148] It is clear that the bending of the lip 17 here then is initiated by a mutual interaction of the proximal sides 24-25 of the locking parts 16 and 18.

[0149] FIG. 7 represents how the floor panels 1A-1B, starting from the coupled condition, can be uncoupled.

[0150] The coupling parts 4-5 are configured such that they allow uncoupling the floor panels 1A-1B, starting from the coupled condition, by means of a rotational movement W1 of the one floor panel 1A around the other floor panel 1B, around an axis parallel to the installation plane and the edges 2-3. In this rotational movement W1 the upper sides 10 of the floor panels 1A-1B are moved towards each other.

[0151] As illustrated in FIG. 7, the rotational movement W1 can be combined with an elastic bending of the lip 17 of the receiving hook 14.

[0152] FIGS. 8 through 11 show more alternatives of the embodiment of the edges 2-3 of the short sides of the floor panels 1A-1B from FIG. 1.

[0153] FIG. 8 represents that the lip 17 of the receiving hook 14 can be provided with an elasticity groove 44 in order to increase the elasticity of the lip 17.

[0154] The elasticity groove 44 here is provided in a lower side of the lip 17 and extends in distal direction up to the distal end of the lip 17. In proximal direction, the groove 44 more particularly extends to beyond the locking surfaces 41-42 of the locking parts 16 and 18.

[0155] It is noted that, as already mentioned herein above, the lower side of the lip 17 preferably is free from grooves or recesses, in order to guarantee the strength of the lip 17.

[0156] FIG. 9 shows that the elasticity groove 44 can be provided in a proximal side 23 of the receiving hook. The groove 44 then extends more particularly into the core of the floor panel 1B.

[0157] It is also noted that the groove 44, provided in the proximal side 23, prolongs the actual length of the lip 17.

[0158] FIG. 10 represents an alternative insertion piece 19, which insertion piece 19 is known as such from the herein above-mentioned WO '893. Here, this relates to a displaceable tongue, which is provided in a displacement groove.

[0159] Although the insertion piece 19 here is provided in a groove present in the distal side 21 of the locking hook 13, according to an alternative the insertion piece 19 can be provided in a groove present in the proximal side 23 of the receiving hook 14. In that case, it can be advantageous to make the displacement groove inclined, such that the insertion piece 19 becomes seated inclined in the floor panel 1B.

[0160] FIG. 11 represents that the locking elements 19-20 can be manufactured from the material of the core 12 of the floor panels 1A-1B, and in one piece therewith. Here, the locking in the direction V perpendicular to the installation plane thus is effected without the assistance of a separate insertion piece or insert.

[0161] Herein, the locking element 19 is made as a protrusion at the distal side 21 of the locking hook 13, whereas the locking element 20 is made as an undercut at the proximal side 23 of the receiving hook 14. However, the reverse is possible, too, wherein the locking element 19 is made as an undercut and the locking element 20 as a protrusion.

[0162] It is also noted that the floor panels 1A-1B, at their short and/or long sides, can be provided with a so-called bevel or chamfer at the upper edges, as is known as such from WO 01/96688 A1. Such bevel can facilitate the installation of the floor panels even more.

[0163] It is also noted that it can be advantageous to provide the coupled edges with a sealing, for example, at the proximal side 23 of the receiving hook 14 and/or at the distal side 21 of the locking hook 13. Such sealing can further reduce or even completely exclude the risk of penetration of moisture or dust.

[0164] It is also noted that, although not represented, for the separate insertion pieces 19 use can also be made of inserts which are used in so-called “side-push” systems, which as such are well-known in the art.

[0165] It is also noted that the dimensions mentioned in the present description, such as lengths and thicknesses, have to be interpreted in the not-coupled condition of the floor panels, if not stated otherwise.

[0166] The present invention is in no way limited to the herein above-described embodiments, on the contrary, such methods, floor panels and carrier material can be realized according to various variants, without leaving the scope of the present invention.