PANEL FOR FORMING A COVERING

Abstract

A panel for forming a covering, includes a first pair of opposite edges and a second pair of opposite edges. The first pair of opposite edges defines a first edge and a second edge of the panel. The second pair of opposite edges defines a third edge and a fourth edge of the panel. The first pair of opposite edges has coupling parts which make it possible for two such panels to be coupled to each other.

Claims

1. A panel, for example a floor panel or a wall panel, for forming a covering, wherein this panel comprises a substrate and a top layer with a decorative surface, wherein the panel comprises a first pair of opposite edges and a second pair of opposite edges; wherein the first pair of opposite edges defines a first edge and a second edge of the panel, and the second pair of opposite edges defines a third edge and a fourth edge of the panel; wherein the first pair of opposite edges comprises coupling parts for coupling two such panels to each other, these coupling parts having the following characteristic features: the coupling parts comprise a vertically active locking system which, in a coupled state of two such panels, brings about a locking at right angles to the plane of the panels; the coupling parts are configured in such a way that two such panels can be coupled to each other along these edges by means of a rotating movement; wherein the second pair of opposite edges comprises coupling parts for coupling two such panels to each other, these coupling parts having the following characteristic features: the coupling parts comprise a horizontally active locking system with horizontally active locking parts which, in a coupled state of two such panels, brings about a locking in the plane of the panels and at right angles to the respective edges; the coupling parts comprise a vertically active locking system with vertically active locking parts which, in a coupled state of two such panels, brings about a locking at right angles to the plane of the panels; the coupling parts are at least composed of an upwardly directed lower hook-shaped portion which is situated on the third edge, and a downwardly directed upper hook-shaped portion which is situated on the fourth edge, wherein the lower hook-shaped portion consists of a lip with an upwardly directed locking element which, proximally therefrom, defines a female part in the form of an upwardly directed recess, whereas the upper hook-shaped portion consists of a lip with a downwardly directed locking element which forms a male part and which, proximally therefrom, defines a downwardly directed recess, wherein the upwardly directed locking element is designed to extend at least partly in the downwardly directed recess and the downwardly directed locking element is designed to extend at least partly in the upwardly directed recess; the coupling parts are configured in such a way that two such panels can be coupled to each other along their respective edges by means of a downward movement of the one panel with respect to the other panel; the third edge comprises an upright first closing surface which extends substantially in the longitudinal direction of the third edge, and the fourth edge comprises an upright second closing surface which is complementary to the first closing surface and extends substantially in the longitudinal direction of the fourth edge, wherein, in the coupled state of two such panels, the first closing surface of the one panel virtually bears against the second closing surface of the other panel, both together thus forming an upright closing surface, this closing surface extending between the decorative surfaces and the vertically and horizontally active locking parts; wherein the second closing surface extends upright from a lower point, wherein a plane which extends parallel to the decorative surface and through this lower point divides the downwardly directed locking element into an upper portion and a lower portion which adjoins this upper portion, so that the lower portion is delimited by a distal side and a proximal side, as well as by a bottom of the downwardly directed locking element, this lower portion being designed to extend at least partly in the upwardly directed recess; characterized in that the panel has the following characteristic feature on the second pair of opposite edges: viewed along the longitudinal direction of the fourth edge, the lower portion of the downwardly directed locking element comprises a first section and a second section wherein, viewed along a direction parallel to the decorative surface and at right angles to the fourth edge, the distal side of the first section extends beyond the distal side of the second section and beyond the second closing surface.

2. The panel as in claim 1, wherein the coupling parts of the first pair of opposite edges are at least formed by a tongue which is situated on the first edge and a groove which is situated on the second edge, wherein the fourth edge, viewed along the longitudinal direction of the fourth edge from the first edge to the second edge, comprises a first half and a second half which adjoins the first half, wherein the first section extends at least at the location of the first half and/or wherein the first section extends between the first edge and the second section.

3. The panel as in claim 1, wherein, viewed along the longitudinal direction of the fourth edge, the length of the first section is at least 20% of the total length of the fourth edge.

4. The panel as in claim 1, wherein, viewed along a direction parallel to the decorative surface and at right angles to the fourth edge, the distal side of the second section extends beyond the second closing surface and/or at least partly extends at the location of the second closing surface.

5. The panel as in claim 1, wherein the first closing surface and the second closing surface extend virtually at right angles to the decorative surface and the closing surface extends virtually at right angles to the decorative surface.

6. The panel as in claim 1, wherein, viewed along the longitudinal direction of the third edge, the design of the upwardly directed recess, and of the lower hook-shaped portion, is virtually constant.

7. The panel as in claim 1, wherein, viewed along the longitudinal direction of the fourth edge, the design of the upper portion of the downwardly directed locking element and/or the design of the downwardly directed recess is virtually constant.

8. The panel as in claim 1, wherein the lower portion of the downwardly directed locking element of the fourth edge comprises a bottom portion at the bottom which is delimited at the bottom by the bottom of the downwardly directed locking element and is designed to extend in the upwardly directed recess of the third edge, with this bottom portion, at least at the location of the first section and along the entire longitudinal direction of the fourth edge, forming the most distal portion of the downwardly directed locking element, and at least a portion of the proximal side of the upwardly directed recess of the third edge extends proximally from and at a distance from the first closing surface, so that the bottom portion is accommodable in the upwardly directed recess.

9. The panel as in claim 1, wherein the vertically active locking parts comprise at least a first locking part which is present on the third edge and extends substantially in the longitudinal direction of the third edge, and a second locking part which is present on the fourth edge and extends substantially in the longitudinal direction of the fourth edge, wherein, in the coupled state of two such panels, the first locking part of the one panel cooperates with the second locking part of the other panel.

10. The panel as in claim 8, wherein the first locking part is situated on the proximal side of the female part and/or the second locking part is situated on the distal side of the bottom portion.

11. The panel as in claim 10, wherein the coupling parts of the second pair of opposite edges are formed as a single part with the material of the panel itself, wherein the first locking part is present on the proximal side of the female part in a solid manner and the second locking part is present on the distal side of the bottom portion in a solid manner.

12. The panel as in claim 1, wherein the coupling parts of the second pair of opposite edges comprise at least a separate locking element which, in a coupled state, cooperates with a locking groove of the coupling parts in order to partly or completely form the vertically active locking parts.

13. The panel as in claim 12, wherein one of the following characteristic features is present: the third edge comprises the separate locking element and the locking groove is present in the fourth edge, wherein the upper side of the bottom portion delimits the underside of the locking groove and wherein, in the coupled state, the separate locking element is in contact with the upper side of the bottom portion, thus forming the first and the second locking part, respectively; or the fourth edge comprises the separate locking element and the locking groove is present in the third edge.

14. The panel as in claim 1, wherein, viewed along the longitudinal direction of the fourth edge, the design of the first section and the second section is constant, wherein the first section directly adjoins the second section; or there is a transition section which gradually spans the distance between the first section and the second section, viewed along a direction parallel to the decorative surface and at right angles to the fourth edge.

15. The panel as in claim 1, wherein, viewed along the longitudinal direction of the fourth edge towards the second section, the distance from the first section to the second closing surface, viewed along a direction at right angles to the fourth edge and parallel to the decorative surface, decreases, decreases gradually, and, viewed along the longitudinal direction of the fourth edge, the design of the second section is constant.

16. The panel as in claim 14, wherein the fourth edge, at the location of said lower portion, only comprises said first section, said second section and the optional transition section.

17. The panel as in claim 1, wherein, viewed along the longitudinal direction of the fourth edge, the distance from the first section to the second closing surface and/or the distance from the second section to the second closing surface changes gradually.

18. The panel as in claim 1, wherein the horizontal locking elements comprise at least a first horizontal locking part which is present on the third edge and extends substantially in the longitudinal direction of the third edge, and a second horizontal locking part which is present on the fourth edge and extends substantially in the longitudinal direction of the fourth edge, wherein the first horizontal locking part extends on the proximal side of the upwardly directed locking element and the second horizontal locking part extends on the distal side of the downwardly directed recess, wherein, in the coupled state of two such panels, the first horizontal locking part of the one panel cooperates with the second horizontal locking part of the other panel and is in contact under pretension.

19. A method for forming a panel as in claim 1, wherein the method comprises at least the following steps: moving the panel relative to cutting and/or milling tools; and treating the edges of the moving panel by means of the cutting and/or milling tools to produce at least some of the coupling parts.

20. The method as in claim 19, wherein, during the treatment of the edge which will form the fourth edge, at least one of the cutting and/or milling tools will be moved towards and/or away from the panel in such a way that the depth of this cutting and/or milling tool in the panel changes in order to form said first and second section.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0127] With a view to providing a better illustration of the characteristic features of the invention, the following text describes a number of preferred embodiments by way of example, without any limiting nature, with reference to the appended drawings, in which:

[0128] FIG. 1 diagrammatically and in perspective shows a portion of a floor covering which consists of floor panels according to the invention during formation of the floor covering;

[0129] FIG. 2 shows the portion which is indicated by F2 in FIG. 1 on an enlarged scale, with the panels being according to the first aspect;

[0130] FIGS. 3 to 7 shows possible cross sections along lines B-B and lines A-A (in dashed lines) of possible embodiments of panels according to the first aspect of the invention;

[0131] FIG. 8 shows a possible cross section along lines VIII-VIII;

[0132] FIG. 9 diagrammatically shows a top view of a floor panel according to the third aspect of the invention;

[0133] FIG. 10 shows a cross section along lines X-X;

[0134] FIG. 11 shows the coupling parts visible in FIG. 10 on an enlarged scale in the coupled state;

[0135] FIG. 12 shows a view of the portion which is indicated by F12 in FIG. 9 on an enlarged scale;

[0136] FIGS. 13, 14, 15 show cross sections on an enlarged scale, respectively along lines XIII-XIII, XIV-XIV and XV-XV in FIG. 12;

[0137] FIGS. 16, 17 and 18 diagrammatically show variants of the embodiment illustrated in FIG. 12;

[0138] FIG. 19 shows another variant in a view similar to that of FIG. 13;

[0139] FIGS. 20 and 21 show yet another variant.

DETAILED DESCRIPTION OF THE INVENTION

[0140] As is illustrated in FIGS. 1 and 2, the invention relates to panels 1, such as floor panels, for forming a covering. These floor panels 1 comprise a first pair of opposite edges 2-3, as well as a second pair of opposite edges 4-5.

[0141] Along their edges, the illustrated floor panels 1 are configured in such a way that they are couplable to each other according to the so-called fold-down principle which consists in the possibility of such floor panels 1 to be coupled to each other along the first pair of opposite edges 2-3 by means of a rotating movement R, and to be coupled to each other along the second pair of opposite edges 4-5 by means of a downward movement M, the downward movement M being the result of the rotating movement R and thus coming about substantially simultaneously. In this case, the floor panels 1 are also configured in such a way along their edges 2-3 and 4-5 that ultimately a locking in both the vertical direction V and the horizontal direction H is brought about, the latter at right angles to the respective edges 2-3 and 4-5.

[0142] The first pair of opposite edges 2-3 defines a first edge 2 and a second edge 3 of the floor panel 1, whereas the second pair of opposite edges 4-5 defines a third edge 4 and a fourth edge 5 of the floor panel 1.

[0143] As is illustrated, such a floor panel 1 is to this end provided with coupling parts 6-7 on its first pair of opposite edges 2-3, whereas coupling parts 8-9 are provided on the second pair of opposite edges 4-5, which coupling parts are described in more detail below with reference to the figures.

[0144] The coupling parts 6-7 of the first pair of opposite edges 2-3 show, both in the embodiments according to the first aspect and the third aspect illustrated here, as can be seen in FIG. 8, at least the following basic characteristic features: [0145] the coupling parts 6-7 comprise a horizontally active locking system which, in a coupled state of two such floor panels 1, brings about a locking in the plane of the floor panels 1 and at right angles to the respective edges 2-3; [0146] the coupling parts 6-7 also comprise a vertically active locking system which, in a coupled state of two such floor panels 1, brings about a locking at right angles to the plane of the floor panels 1; [0147] the coupling parts 6-7 are produced as a single part with the material of the floor panel 1 itself; and [0148] the coupling parts 6-7 are configured in such a way that two such panels 1 on these edges can be coupled to each other by means of a rotating movement R.

[0149] FIGS. 2 to 7 show possible embodiments of the first aspect of the invention. As can be seen in FIGS. 2 to 7, the coupling parts 8-9 of the second pair of opposite edges 4-5 at least have the following basic characteristic features: [0150] the coupling parts 8-9 comprise a horizontally active locking system with horizontally active locking parts which, in a coupled state of two such panels 1, brings about a locking in the plane of the panels 1 and at right angles to the respective edges 4-5; [0151] the coupling parts 8-9 comprise a vertically active locking system with vertically active locking parts which, in a coupled state of two such panels 1, brings about a locking at right angles to the plane of the panels 1; [0152] the coupling parts 8-9 are at least composed of an upwardly directed lower hook-shaped portion 10 which is situated on the third edge 4, and a downwardly directed upper hook-shaped portion 11 which is situated on the fourth edge 5, wherein the lower hook-shaped portion 10 consists of a lip 12 with an upwardly directed locking element 13 which, proximally therefrom, defines a female part in the form of an upwardly directed recess 14, whereas the upper hook-shaped portion 11 consists of a lip 15 with a downwardly directed locking element 16 which forms a male part and which, proximally therefrom, defines a downwardly directed recess 17, wherein the upwardly directed locking element 13 is designed to extend at least partly in the downwardly directed recess 17 and the downwardly directed locking element 16 is designed to extend at least partly in the upwardly directed recess 14; [0153] the coupling parts 8-9 are configured in such a way that two such panels I can be coupled to each other along their respective edges 4-5 by means of a downward movement M of the one panel 1 with respect to the other panel 1; [0154] the third edge 4 comprises an upright first closing surface which extends substantially in the longitudinal direction of the third edge 4, and the fourth edge 5 comprises an upright second closing surface which is complementary to the first closing surface and extends substantially in the longitudinal direction of the fourth edge 5, wherein, in the coupled state of two such panels 1, the first closing surface of the one panel 1 bears against the second closing surface of the other panel 1, both together thus forming an upright closing surface S, this closing surface S extending between the decorative surfaces and the vertically and horizontally active locking parts; [0155] wherein the second closing surface extends upright from a lower point, wherein a plane A which extends parallel to the decorative surface and through this lower point divides the downwardly directed locking element 16 into an upper portion 29 and a lower portion 30 which adjoins this upper portion 29, so that the lower portion 30 is delimited by a distal side and a proximal side, as well as by a bottom of the downwardly directed locking element 16, this lower portion 30 being designed to extend at least partly in the upwardly directed recess 14; [0156] viewed along the longitudinal direction of the fourth edge 5, the lower portion 30 of the downwardly directed locking element 16 comprises a first section 31 and a second section 32, wherein, viewed along a direction parallel to the decorative surface and at right angles to the fourth edge 5, the distal side of the first section 31 extends beyond the distal side of the second section 32 and beyond the second closing surface; [0157] the fourth edge 5, viewed along the longitudinal direction of the fourth edge 5 from the first edge 2 to the second edge 3, comprises a first half and a second half which adjoins the first half, wherein the first section 31 extends at the location of the first half and the first section 31 extends between the first edge 2 and the second section 32, and wherein the second section 32 extends at the location of the second half; [0158] viewed along the longitudinal direction of the fourth edge 5, the length of the first section 31 is at least 20% of the total length of the fourth edge 5, preferably at least 30% and most preferably virtually 40%; [0159] viewed along a direction parallel to the decorative surface and at right angles to the fourth edge 5, the distal side of the second section 32 extends beyond the second closing surface and/or at least partly extends at the location of the second closing surface; [0160] the first closing surface and the second closing surface extend virtually at right angles to the decorative surface and the closing surface S extends virtually at right angles to the decorative surface; [0161] viewed along the longitudinal direction of the third edge 4, the design of the upwardly directed recess 14 is virtually constant; [0162] viewed along the longitudinal direction of the fourth edge 5, the design of the upper portion 29 of the downwardly directed locking element 16 and the design of the downwardly directed recess 17 is virtually constant; [0163] the lower portion 30 of the downwardly directed locking element 16 of the fourth edge 5 comprises a bottom portion at the bottom which is delimited at the bottom by the bottom of the downwardly directed locking element 16 and is designed to extend in the upwardly directed recess 14 of the third edge 4, with this bottom portion, at least at the location of the first section 31 and preferably along the entire longitudinal direction, forming the most distal portion of the downwardly directed locking element 16, and at least a portion of the proximal side of the upwardly directed recess 14 of the third edge 4 extends proximally from and at a distance from the first closing surface, so that the bottom portion is accommodable in the upwardly directed recess 14; [0164] the horizontal locking elements comprise at least a first horizontal locking part 36 which is present on the third edge 4 and extends substantially in the longitudinal direction of the third edge 4, and a second horizontal locking part 37 which is present on the fourth edge 5 and extends substantially in the longitudinal direction of the fourth edge 5, wherein the first horizontal locking part 36 extends on the proximal side of the upwardly directed locking element 13 and the second horizontal locking part 37 extends on the distal side of the downwardly directed recess 17, wherein, in the coupled state of two such panels 1, the first horizontal locking part 36 of the one panel 1 cooperates with the second horizontal locking part 37 of the other panel 1 and this with or without pretension; [0165] viewed along the longitudinal direction of the fourth edge 5, the design of the first section 31 and the second section 32 is preferably constant, wherein the first section 31 directly adjoins the second section 32, or a transition section 35 is present which gradually spans the distance between the first section 31 and the second section 32, viewed along a direction parallel to the decorative surface and at right angles to the fourth edge 5, and this viewed along the longitudinal direction of the fourth edge 5.

[0166] As can be seen in FIGS. 3 and 4, the coupling parts 8-9 of the second pair of opposite edges 4-5 have further characteristic features: [0167] the vertically active locking parts at least comprise a first locking part 23 which is present on the third edge 4 and extends substantially in the longitudinal direction of the third edge 4, and a second locking part 24 which is present on the fourth edge 5 and extends substantially in the longitudinal direction of the fourth edge 5, wherein, in the coupled state of two such panels 1, the first locking part 23 of the one panel 1 cooperates with the second locking part 24 of the other, wherein the first locking part 23 is situated on the proximal side of the female part and the second locking part 24 is situated on the distal side of the bottom portion. [0168] the coupling parts 8-9 of the second pair of opposite edges 4-5 are formed as a single part with the material of the panel 1 itself, and the first locking part 23 is present on the proximal side of the female part in a solid manner and the second locking part 24 is present on the distal side of the bottom portion in a solid manner; [0169] the second locking part 24 forms part of the bottom portion, and preferably the first and the second locking part 23-24 form cooperating locking faces, these locking faces extending virtually parallel to the horizontal plane; [0170] the vertical locking elements at least comprise a third locking part 38 which is present on the third edge 4 and extends substantially in the longitudinal direction of the third edge 4, and a fourth locking part 27 which is present on the fourth edge 5 and extends substantially in the longitudinal direction of the fourth edge 5, wherein the third locking part 38 extends on the distal side of the upwardly directed locking element 13 and the fourth locking part 27 extends on the proximal side of the downwardly directed recess 17, wherein, in the coupled state of two such panels 1, the third locking part 38 of the one panel 1 can be brought into cooperation with the fourth locking part 27 of the other panel 1.

[0171] As can be seen in FIGS. 5 to 7, the coupling parts 8-9 of the second pair of opposite edges 4-5 have further characteristic features: [0172] the coupling parts 8-9 of the second pair of opposite edges 4-5 comprise at least a separate locking element 33 which, in a coupled state, cooperates with a locking groove 34 of the coupling parts 8-9 in order to partly or completely form the vertically active locking parts; [0173] the locking element 33, at least in a coupled state, bears against the bottom portion; [0174] with the embodiment illustrated in FIG. 6, the third edge 4 comprises the separate locking element 33 and the locking groove 34 is present in the fourth edge 5, wherein the upper side of the bottom portion delimits the underside of the locking groove 34 and wherein, in a coupled state, the separate locking element 33 is in contact with the upper side of the bottom portion and thus forms the first and the second vertically active locking part 23-24, respectively; [0175] with the embodiments illustrated in FIGS. 5 and 7, the fourth edge 5 comprises the separate locking element 33 and the locking groove 34 is present in the third edge 4; [0176] as can be seen in FIGS. 6 and 7, the lip 12 of the third edge 4 is bent in the coupled state of two panels 1 and there is therefore a case of pretension.

[0177] As can be seen in FIG. 8, the first pair of opposite edges 2-3 comprises a tongue 25 which is situated on the first edge 2, and a groove 26 which is situated on the second edge 3. FIGS. 9 to 21 illustrate the third aspect of the invention.

[0178] As can be seen in FIGS. 10 and 11, the coupling parts 8-9 of the second pair of opposite edges 4-5 have at least the following basic characteristic features: [0179] the coupling parts 8-9 comprise a horizontally active locking system which, in a coupled state of two such floor panels 1, brings about a locking in the plane of the floor panels 1 and at right angles to the respective edges 4-5; [0180] the coupling parts 8-9 also comprise a vertically active locking system which, in a coupled state of two such floor panels 1, brings about a locking at right angles to the plane of the floor panels 1; [0181] the coupling parts 8-9 are formed as a single part with the material of the floor panel 1 itself; [0182] the horizontally active locking system of the second pair of opposite edges 4-5 is at least composed of an upwardly directed lower hook-shaped portion 10 which is situated on one of aforementioned two edges 4, as well as a downwardly directed upper hook-shaped portion 11 which is situated on the opposite edge 5, wherein the lower hook-shaped portion 10 consists of a lip 12 with an upwardly directed locking element 13 which, proximally therefrom, defines a female part in the form of an upwardly directed recess 14, whereas the upper hook-shaped portion 11 consists of a lip 15 with a downwardly directed locking element 16 which forms a male part; [0183] the coupling parts 8-9 are configured in such a way that two such floor panels 1 can be couple to each other along their respective edges 4-5 by means of a downward movement M of the one panel 1 with respect to the other panel 1; [0184] the aforementioned female part is delimited by a distal side 18 and a proximal side 19, as well as by a bottom 20 which is formed by the upper side of the lip 12 of the lower hook-shaped portion 10; [0185] the aforementioned male part is delimited by a distal side 21 and a proximal side 22; [0186] the vertically active locking system comprises vertically active locking parts; [0187] the vertically active locking parts are at least formed by a first locking part 23 which is present on the aforementioned third edge 4 and extends substantially in the longitudinal direction of the third edge 4, and a second locking part 24 which is present on the aforementioned fourth edge 5 and extends substantially in the longitudinal direction of the fourth edge 5, wherein, in the coupled state of two such floor panels 1, the first locking part 23 of the one floor panel 1 cooperates with the second locking part 24 of the other floor panel 1; and [0188] the first locking part 23 and the second locking part 24 are situated at levels which are higher than the aforementioned bottom 20 of the female part.

[0189] The peculiarity of the present invention is that the floor panel 1 furthermore has the following combination of characteristic features on the second pair of opposite edges 4 5: [0190] the first locking part 23 is situated on the proximal side 19 of the female part and is in this case present on this proximal side 19 in a solid manner; [0191] the second locking part 24 is situated on the distal side 21 of the male part and is in this case preferably also present on this distal side 21 in a solid manner; and [0192] at least one of the locking parts 23-24 of the pair of locking parts which is formed by the first locking part 23 and the second locking part 24 is of a variable design in the longitudinal direction of the respective edge.

[0193] It should be noted that the proximal side 19 of the female part, as is illustrated in the figures, is that side 19 which is situated closest, i.e. most proximal, to the centre of the floor panel 1.

[0194] In this description, the proximal side 19 has to regarded as extending across the entire height from the bottom 20 up to the upper side of the floor panel 1. When reference is made to the distal side 21 of the male part, this is understood to mean the entire distal side of the upper hook-shaped portion 11, i.e. the side from the underside of the male part up to the upper side of the floor panel 1.

[0195] The variable design intended by the invention will be explained by means of a number of illustrated embodiments and with reference to FIGS. 12 to 15.

[0196] In the example of FIGS. 12 to 15, the form of the first locking part 23 varies in such a way that, in the coupled state, the transverse overlap between the first locking part 23 and the second locking part 24, and in particular of the respective contact surfaces thereof, varies in the longitudinal direction. In this example, the overlap varies between a state in which it is non-existent and a maximum state, i.e. from the end of the third edge 4 towards the centre of the edge. The course of this variation which, in this example, occurs gradually can be seen in FIG. 12, as well as from the specific cross sections which are illustrated in FIGS. 13, 14 and 15. In FIG. 13, there is no overlap of the contact surfaces, in FIG. 14 there is a slight overlap, and in FIG. 15 the maximum overlap used is shown. It will be clear that in the embodiment from FIGS. 12 to 15, only the design of the first locking part 23 varies, whereas the design of the second locking part 24 remains constant or virtually constant along the entire length.

[0197] The gradual variation, in the particular the gradual increase in the overlap, offers the advantage that the second locking part 24 is guided behind the first locking part 23 in a smoother manner during the rotating movement from FIG. 2. The risk of two floor panels 1 being pushed apart at the start of the rotation due to the locking parts 23-24 being pushed along each other, which may result in permanent gaps, is also reduced.

[0198] Due to the fact that the variable design is used on one or more locking parts 23-24, in this case the aforementioned first locking part 23 which, in contrast to what is known from WO2010/100046, are now not situated at the distal end of the lower lip, these locking parts are situated in a better position to be pressed one after the other, resulting in a stronger and stabler snap coupling.

[0199] FIGS. 16 and 17 show variants in which the first locking part 23 varies by the fact that it is in each case composed of several spaced apart locking portions 23A-23B-23C, wherein the first locking part in the intermediate areas may be regarded as a missing locking part and may be regarded as a present locking part at the location of the aforementioned portions, so that, viewed overall, there is a variation. It will be clear that when such a first locking part 23 from FIGS. 16 and 17 is used in combination with a second locking part 24 having the same continuous shape which continues along the respective edge, this will result in a varying overlap at the contact surfaces in the coupled state.

[0200] In the embodiment from FIG. 16, gradual transitions 28 are used, whereas stepwise transitions are used in FIG. 17.

[0201] FIG. 18 illustrates another variant in which the first locking part 23 is configured to have an oscillating shape.

[0202] FIG. 19 shows that the varying overlap can also be achieved by making the second locking part 24 of a varying design depending on the longitudinal direction of the edge. In this case, the second locking part 24 varies between a position P1 in which there is an overlap, with a shape as shown by the dashed line, and a position P2 in which the overlap is zero or is virtually zero, as shown by a solid line in FIG. 19. In this case, it is the aim for the first locking part 23 to have a continuous path of the same shape.

[0203] FIGS. 20 and 21 show a variant which varies in that the angular position of the contact surface of the first locking part 23 varies. In this case, FIGS. 20 and 21 show cross sections at two locations along the same pair of edges. FIG. 20 shows a normal position in which the respective contact surfaces are positioned against one another. FIG. 21 shows the position of the contact surfaces at another location, in which the second locking part 24 only touches the contact surface of the first locking part 23 at a corner. The shape from FIG. 21 may, for example, be used at the start of an edge in such a way that, for example in combination with the fold-down technique, the second locking part 24 can be brought underneath the first locking part 23 more quickly.

[0204] According to yet another possibility, the contact surfaces of both locking parts 23-24 remain parallel, but the mutual angle which they assume depending on the location on the edge varies.

[0205] The invention can be used with all kinds of floor panels 1. However, it is particularly suitable for relatively thin panels 1 with a thickness of less than 1 cm.

[0206] The invention according to the first, second or third aspect can efficiently be used with laminate floor panels, for example DPL or HPL, with preferably a wood-based substrate, for example MDF or HDF, as well as with plastic-based floor panels. Such plastic-based floor panels may be of various kinds. Non-limiting examples are: slightly foamed hard WPC panels, hard plastic panels and flexible plastic panels, such as LVT panels or similar panels made of a plastic other than vinyl.

[0207] It will be clear that the floor panels 1 preferably have a decorative upper side, for example in the form of a printed layer. In the case of a printed layer, this may be both a layer which has first been printed on a substrate which subsequently becomes part of the floor panel 1, and a printed layer which has been printed directly onto the floor panel 1, optionally using intermediate layers. Also, protective layers, such as wear layers may be provided.

[0208] According to an important preferred characteristic feature of the third aspect of the invention, the floor panel 1 is characterized in that that the first locking part 23 and/or the second locking part 24 are composed of one or more portions, for example 23 in FIG. 12 and for example 23A-23B-23C in FIGS. 16 to 18, as a result of which, in the coupled state, one or more overlap zones between the first locking part 23 and the second locking part 24 are formed; in that such an overlap zone is characterized by a maximum transverse overlap OT and a maximum longitudinal overlap OL, as is indicated in a number of the figures; and in that the maximum longitudinal overlap OL for at least one overlap zone at least satisfies one of following, and preferably several of the following criteria: [0209] the longitudinal overlap OL is at least 3 millimetres; [0210] the longitudinal overlap OL is at least 5 millimetres; [0211] the longitudinal overlap OL is at least 10 millimetres; [0212] the longitudinal overlap OL is at least 20 millimetres; [0213] the longitudinal overlap OL is at least 3 times the size of the transverse overlap OT; [0214] the longitudinal overlap OL is at least 10 times the size of the transverse overlap OT; [0215] the longitudinal overlap OL is at least 100 times the size of the transverse overlap OT; [0216] the longitudinal overlap (OL) is so large that, at the location of the centre of the longitudinal overlap (OL), the compressibility of the locking portions is essentially not affected by any absence of material at the longitudinal ends of the overlap zone.

[0217] The latter is particularly useful to ensure a strong locking.

[0218] If several overlap zones are present along the respective edges, then it is preferable for the majority thereof and preferably all overlap zones to satisfy one or more of the aforementioned criteria.

[0219] The present invention also relates to the following list of items: [0220] 1.A panel, for example a floor panel or a wall panel, for forming a covering, [0221] wherein this panel (1) comprises a substrate and a top layer with a decorative surface, wherein the panel (1) comprises a first pair of opposite edges (2-3) and a second pair of opposite edges (4-5); [0222] wherein the first pair of opposite edges (2-3) defines a first edge (2) and a second edge (3) of the panel (1), and the second pair of opposite edges (4-5) defines a third edge (4) and a fourth edge (5) of the panel (1); [0223] wherein the first pair of opposite edges (2-3) comprises coupling parts (6-7) for coupling two such panels (1) to each other, these coupling parts (6-7) having the following characteristic features: [0224] the coupling parts (6-7) optionally comprise a horizontally active locking system which, in a coupled state of two such panels (1), brings about a locking in the plane of the panels (1) and at right angles to the respective edges (2-3); [0225] the coupling parts (6-7) comprise a vertically active locking system which, in a coupled state of two such panels (1), brings about a locking at right angles to the plane of the panels (1); [0226] the coupling parts (6-7) are configured in such a way that two such panels (1) can be coupled to each other along these edges by means of a rotating movement (R); [0227] wherein the second pair of opposite edges (4-5) comprises coupling parts (8-9) for coupling two such panels (1) to each other, these coupling parts (8-9) having the following characteristic features: [0228] the coupling parts (8-9) comprise a horizontally active locking system with horizontally active locking parts which, in a coupled state of two such panels (1), brings about a locking in the plane of the panels (1) and at right angles to the respective edges (4-5); [0229] the coupling parts (8-9) comprise a vertically active locking system with vertically active locking parts which, in a coupled state of two such panels (1), brings about a locking at right angles to the plane of the panels (1); [0230] the coupling parts (8-9) are at least composed of an upwardly directed lower hook-shaped portion (10) which is situated on the third edge (4), and a downwardly directed upper hook-shaped portion (11) which is situated on the fourth edge (5), wherein the lower hook-shaped portion (10) consists of a lip (12) with an upwardly directed locking element (13) which, proximally therefrom, defines a female part in the form of an upwardly directed recess (14), whereas the upper hook-shaped portion (11) consists of a lip (15) with a downwardly directed locking element (16) which forms a male part and which, proximally therefrom, defines a downwardly directed recess (17), wherein the upwardly directed locking element (13) is designed to extend at least partly in the downwardly directed recess (17) and the downwardly directed locking element (16) is designed to extend at least partly in the upwardly directed recess (14); [0231] the coupling parts (8-9) are configured in such a way that two such panels (1) can be coupled to each other along their respective edges (4-5) by means of a downward movement (M) of the one panel (1) with respect to the other panel (1); [0232] the third edge (4) comprises an upright first closing surface which extends substantially in the longitudinal direction of the third edge (4), and the fourth edge (5) comprises an upright second closing surface which is complementary to the first closing surface and extends substantially in the longitudinal direction of the fourth edge (5), wherein, in the coupled state of two such panels (1), the first closing surface of the one panel (1) virtually bears against the second closing surface of the other panel (1), both together thus forming an upright closing surface(S), this closing surface extending between the decorative surfaces and the vertically and horizontally active locking parts; [0233] wherein the second closing surface extends upright from a lower point, wherein a plane (A) which extends parallel to the decorative surface and through this lower point divides the downwardly directed locking element (16) into an upper portion (29) and a lower portion (30) which adjoins this upper portion (29), so that the lower portion (30) is delimited by a distal side and a proximal side, as well as by a bottom of the downwardly directed locking element (16), this lower portion (30) being designed to extend at least partly in the upwardly directed recess (14); [0234] characterized in that the panel (1) has the following characteristic feature on the second pair of opposite edges (4-5): [0235] viewed along the longitudinal direction of the fourth edge (5), the lower portion (30) of the downwardly directed locking element (16) comprises a first section (31) and a second section (32) wherein, viewed along a direction parallel to the decorative surface and at right angles to the fourth edge (5), the distal side of the first section (31) extends beyond the distal side of the second section (32) and beyond the second closing surface. [0236] 2.The panel in accordance with item 1, wherein the coupling parts (6, 7) of the first pair of opposite edges (2-3) are at least formed by a tongue (25) which is situated on the first edge (2) and a groove (26) which is situated on the second edge (3), wherein the fourth edge (5), viewed along the longitudinal direction of the fourth edge (5) from the first edge (2) to the second edge (3), comprises a first half and a second half which adjoins the first half, wherein the first section (31) extends at least at the location of the first half and/or wherein the first section (31) extends between the first edge (2) and the second section (32). [0237] 3.The panel in accordance with item 1 or 2, wherein, viewed along the longitudinal direction of the fourth edge (5), the length of the first section (31) is at least 20% of the total length of the fourth edge (5), preferably at least 30% and most preferably at least 40%. [0238] 4.The panel in accordance with one of the preceding items, wherein, viewed along a direction parallel to the decorative surface and at right angles to the fourth edge (5), the distal side of the second section (32) extends beyond the second closing surface and/or at least partly extends at the location of the second closing surface. [0239] 5.The panel in accordance with one of the preceding items, wherein the first closing surface and the second closing surface extend virtually at right angles to the decorative surface and the closing surface(S) extends virtually at right angles to the decorative surface. [0240] 6.The panel in accordance with one of the preceding items, wherein, viewed along the longitudinal direction of the third edge (4), the design of the upwardly directed recess (14), and preferably of the lower hook-shaped portion (10), is virtually constant. [0241] 7.The panel in accordance with one of the preceding items, wherein, viewed along the longitudinal direction of the fourth edge (5), the design of the upper portion (29) of the downwardly directed locking element (16) and/or the design of the downwardly directed recess (17) is virtually constant. [0242] 8.The panel in accordance with one of the preceding items, wherein the lower portion (30) of the downwardly directed locking element (16) of the fourth edge (5) comprises a bottom portion at the bottom which is delimited at the bottom by the bottom of the downwardly directed locking element (16) and is designed to extend in the upwardly directed recess (14) of the third edge (4), with this bottom portion, at least at the location of the first section (31) and preferably along the entire longitudinal direction of the fourth edge (5), forming the most distal portion of the downwardly directed locking element (16), and at least a portion of the proximal side of the upwardly directed recess (14) of the third edge (4) extends proximally from and at a distance from the first closing surface, so that the bottom portion is accommodable in the upwardly directed recess (14). [0243] 9.The panel in accordance with one of the preceding items, wherein the vertically active locking parts comprise at least a first locking part (23) which is present on the third edge (4) and extends substantially in the longitudinal direction of the third edge (4), and a second locking part (24) which is present on the fourth edge (5) and extends substantially in the longitudinal direction of the fourth edge (5), wherein, in the coupled state of two such panels (1), the first locking part (23) of the one panel (1) cooperates with the second locking part (24) of the other panel. [0244] 10.The panel in accordance with item 8 and 9, wherein the first locking part (23) is situated on the proximal side of the female part and/or the second locking part (24) is situated on the distal side of the bottom portion. [0245] 11.The panel in accordance with item 10, wherein the coupling parts (8-9) of the second pair of opposite edges (4-5) are formed as a single part with the material of the panel (1) itself, wherein the first locking part (23) is present on the proximal side of the female part in a solid manner and the second locking part (24) is present on the distal side of the bottom portion in a solid manner. [0246] 12.The panel in accordance with item 8 and 11, wherein the second locking part (24) forms part of the bottom portion, and preferably the first and the second locking part (23, 24) form cooperating locking faces, these locking faces extending virtually parallel to the decorative surface. [0247] 13.The panel in accordance with one of items 1 to 10, wherein the coupling parts (8-9) of the second pair of opposite edges (4-5) comprise at least a separate locking element (33) which, in a coupled state, cooperates with a locking groove (34) of the coupling parts (8-9) in order to partly or completely form the vertically active locking parts. [0248] 14.The panel in accordance with item 8 or 10 and in accordance with item 13, wherein the locking element (33), at least in the coupled state, bears against the bottom portion. [0249] 15.The panel in accordance with item 13 or 14, wherein one of the following characteristic features is present: [0250] the third edge (4) comprises the separate locking element (33) and the locking groove (34) is present in the fourth edge (5), wherein the upper side of the bottom portion preferably delimits the underside of the locking groove (34) and wherein, in the coupled state, the separate locking element (33) is in contact with the upper side of the bottom portion, thus forming the first and the second locking part (23-24), respectively; or [0251] the fourth edge (5) comprises the separate locking element (33) and the locking groove (34) is present in the third edge (4). [0252] 16.The panel in accordance with one of the preceding items, wherein, viewed along the longitudinal direction of the fourth edge (5), the design of the first section (31) and the second section (32) is constant, wherein preferably [0253] the first section (31) directly adjoins the second section (32); or [0254] there is a transition section (35) which gradually spans the distance between the first section (31) and the second section (32), viewed along a direction parallel to the decorative surface and at right angles to the fourth edge (5). [0255] 17.The panel in accordance with one of the preceding items 1 to 15, wherein, viewed along the longitudinal direction of the fourth edge (5) towards the second section (32), the distance from the first section (31) to the second closing surface, viewed along a direction at right angles to the fourth edge (5) and parallel to the decorative surface, decreases, preferably decreases gradually, and preferably, viewed along the longitudinal direction of the fourth edge (5), the design of the second section (32) is constant. [0256] 18.The panel in accordance with item 16 or 17, wherein the fourth edge (5), at the location of said lower portion (30), only comprises said first section (31), said second section (32) and the optional transition section (35). [0257] 19.Th panel in accordance with one of the preceding items 1 to 15, wherein, viewed along the longitudinal direction of the fourth edge (5), the distance from the first section (31) to the second closing surface and/or the distance from the second section (32) to the second closing surface changes gradually. [0258] 20.The panel in accordance with one of the preceding items, wherein the horizontal locking elements comprise at least a first horizontal locking part (36) which is present on the third edge (4) and extends substantially in the longitudinal direction of the third edge (4), and a second horizontal locking part (37) which is present on the fourth edge (5) and extends substantially in the longitudinal direction of the fourth edge (5), wherein the first horizontal locking part (36) extends on the proximal side of the upwardly directed locking element (13) and the second horizontal locking part (37) extends on the distal side of the downwardly directed recess (17), wherein, in the coupled state of two such panels (1), the first horizontal locking part (36) of the one panel (1) cooperates with the second horizontal locking part (37) of the other panel and is in contact under pretension. [0259] 21.Method for forming a panel as in one or more of items 1 to 20, wherein the method comprises at least the following steps: [0260] moving the panel (1) relative to cutting and/or milling tools (55-56-57); and [0261] treating the edges (2-3-4-5) of the moving panel (1) by means of the cutting and/or milling tools (55-56-57) to produce at least some of the coupling parts (6-7-8-9). [0262] 22.Method in accordance with item 21, wherein, during the treatment of the edge which will form the fourth edge (5), at least one of the cutting and/or milling tools will be moved towards and/or away from the panel (1) in such a way that the depth of this cutting and/or milling tool (56) in the panel (1) changes in order to form said first and second section (31-32). [0263] 23.Method in accordance with item 22, wherein, during the treatment of the edge which will form the fourth edge (5), said cutting and/or milling tool (56) is moved away from the panel (1), so that the second section (32) is formed first, followed by the first section (31). [0264] 24.Method in accordance with one of the preceding items 21 to 23, wherein the coupling parts (6-7) of the first pair of opposite edges (2-3) are formed by means of stationary cutting or milling tools. [0265] 25.Method in accordance with one of the preceding items 21 to 24, wherein the cutting or milling tools are rotating cutting or milling tools. [0266] 26.A panel, for example a floor panel or a wall panel, for forming a covering, and optionally in accordance with one or more of items 1 to 20, [0267] wherein this panel (1) comprises a substrate and a top layer with a decorative surface, wherein the panel (1) comprises a first pair of opposite edges (2-3) and a second pair of opposite edges (4-5); [0268] wherein the first pair of opposite edges (2-3) defines a first edge (2) and a second edge (3) of the panel (1), and the second pair of opposite edges (4-5) defines a third edge (4) and a fourth edge (5) of the panel (1); [0269] wherein the first pair of opposite edges (2-3) comprises coupling parts (6-7) for coupling two such panels (1) to each other, wherein these coupling parts (6-7) have the following characteristic features: [0270] the coupling parts (6-7) optionally comprise a horizontally active locking system which, in a coupled state of two such panels (1), brings about a locking in the plane of the panels (1) and at right angles to the respective edges (2-3); [0271] the coupling parts (6-7) comprise a vertically active locking system which, in a coupled state of two such panels (1), brings about a locking at right angles to the plane of the panels (1); [0272] the coupling parts (6-7) are configured in such a way that two such panels (1) can be coupled to each other along these edges by means of a rotating movement (R); [0273] wherein the second pair of opposite edges (4-5) comprises coupling parts (8-9) for coupling two such panels (1) to each other, wherein these coupling parts (8-9) have the following characteristic features: [0274] the coupling parts (8-9) comprise a horizontally active locking system with horizontally active locking parts which, in a coupled state of two such panels (1), brings about a locking in the plane of the panels (1) and at right angles to the respective edges (4-5); [0275] the coupling parts (8-9) comprise a vertically active locking system with vertically active locking parts which, in a coupled state of two such panels (1), brings about a locking at right angles to the plane of the panels (1); [0276] the coupling parts (8-9) are formed as a single part with the material of the panel (1) itself; [0277] the coupling parts (8, 9) are at least formed by an upwardly directed lower hook-shaped portion (10) which is situated on the third edge (4), and a downwardly directed upper hook-shaped portion (11) which is situated on the fourth edge (5), wherein the lower hook-shaped portion (10) consists of a lip (12) with an upwardly directed locking element (13) which, proximally therefrom, defines a female part in the form of an upwardly directed recess (14), whereas the upper hook-shaped portion (11) consists of a lip (15) with a downwardly directed locking element (16) which forms a male part and which, proximally therefrom, defines a downwardly directed recess (17), wherein the upwardly directed locking element (13) is designed to extend at least partly in the downwardly directed recess (17) and the downwardly directed locking element (16) is designed to extend at least partly in the upwardly directed recess (14); [0278] the coupling parts (8-9) are configured in such a way that two such panels (1) can be coupled to each other along their respective edges (4-5) by means of a downward movement (M) of the one panel (1) with respect to the other panel (1); [0279] the vertically active locking parts are at least formed by a first locking part (23) which is present on the aforementioned third edge (4) and extends substantially in the longitudinal direction of the third edge (4), and a second locking part (24) which is present on the aforementioned fourth edge (5) and extends substantially in the longitudinal direction of the fourth edge (5), wherein, in the coupled state of two such panels (1), the first locking part (23) of the one panel (1) cooperates with the second locking part (24) of the other; and [0280] the first locking part (23) and the second locking part (24) are situated at levels which are higher than a bottom of the upwardly directed recess (14); [0281] characterized in that the panel (1) has the following combination of characteristic features on the second pair of opposite edges (4-5): [0282] the first locking part (23) is situated on the proximal side of the female part and is in this case present on this proximal side in a solid manner; [0283] the second locking part (24) is situated on the distal side of the male part and is in this case present on this distal side in a solid manner; and [0284] at least one of the locking parts (23-24) of the pair of locking parts (23-24) which is formed by the first locking part (23) and the second locking part (24) is of a variable design in the longitudinal direction of the respective edge (4-5), wherein preferably said variable design provides for the cross section of at least one of the locking parts (23-24) of the aforementioned pair of locking parts (23-24) to vary and the variable design is configured in such a way that, in a coupled state, the transverse overlap (OT) between the first locking part (23) and the second locking part (24) varies in the longitudinal direction. [0285] 27.The panel in accordance with item 26, wherein the first locking part (23) and the second locking part (24) are provided with contact surfaces and the aforementioned variable design provides for the contact surface of the first locking part (23) and/or the contact surface of the second locking part (24) to change in angular position or shape. [0286] 28.The panel in accordance with item 27, wherein the contact surfaces are configured in such a way that at least the angle of the tangent line which is defined by the contact surfaces in the coupled position varies in the longitudinal direction. [0287] 29.The panel in accordance with item 27 or 28, wherein the contact surfaces are configured in such a way that at least the position where the contact surfaces come into contact with each other, viewed in the height and/or transverse direction, varies depending on the longitudinal direction.

[0288] The present invention is by no means limited to the embodiments described as examples and illustrated in the figures, but such a floor panel, and in the particular the coupling parts, can be brought about in different shapes and dimensions without departing from the scope of the invention.