Floor panel for forming a floor covering

Abstract

Floor panel, characterized in that it is of the type that can be installed according to the fold down-technique, that it comprises coupling means in one piece on all four edges, and that measures are taken in order to avoid an undesired shifting on the long edges during the turning down of the floor panel.

Claims

1-31. (canceled)

32. A floor panel for forming a floor covering, wherein this floor panel is rectangular and oblong and comprises: a first pair of opposite edges, which form the long edges of the floor panel, and a second pair of opposite edges, which form the short edges of the floor panel; wherein both pairs of opposite edges comprise coupling parts, which allow that a plurality of such floor panels mutually can be coupled to each other; wherein these coupling parts, on both pairs of edges, form a first locking system, which, in a coupled condition of two of such floor panels, effects a locking in the plane of the floor panels and perpendicular to the respective edges, and form a second locking system, which, in a coupled condition of two of such floor panels, effects a locking transverse to the plane of the floor panels; wherein these coupling parts on the first pair of opposite edges substantially are realized in the material of the floor panel itself; wherein the coupling parts of at least the first pair of opposite edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a turning movement and to this aim these coupling parts on the first pair of opposite edges consist of a tongue and a groove, and locking parts, which, in the coupled condition, prevent the shifting apart of the tongue and groove; wherein on the first pair of opposite edges the groove is bordered by a lower lip and an upper lip, of which the lower lip extends laterally up to beyond the distal extremity of the upper lip; wherein the coupling parts on the second pair of edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a downward movement of one floor panel in respect to the other, such that a plurality of such floor panels can be coupled to each other by means of a “fold-down” technique; wherein the first locking system of the second pair of edges is at least formed of an upward-directed lower hook-shaped part, which is situated on one of said two edges and which comprises a distal extremity, and a downward-directed upper hook-shaped part, which is situated on the opposite edge, wherein the lower hook-shaped part consists of a lip with an upward-directed locking element, whereas the upper hook-shaped part consists of a lip with a downward-directed locking element; wherein the second locking system of the second pair of edges is at least formed by a locking part, which is situated on the distal extremity of the lower hook-shaped part, and a locking part, which cooperates therewith in the coupled condition of two of such floor panels, on the edge which comprises the upper hook-shaped part; wherein the distal extremity of the upper hook-shaped part and the side which, in coupled condition, is opposite thereto, are free from mutually vertically locking portions; wherein the coupling parts on the first pair of edges are configured such that during the turning into each other of two of such floor panels an elastic force has to be overcome during the turning movement, which force, during the turning into each other, first increases in order to subsequently decrease again; wherein the floor panels on the first pair of edges, in the final coupled condition of two of such floor panels, are coupled in horizontal direction free from play, or, if such play indeed exists, this play is less than 0.2 mm; wherein the aforementioned locking parts of the first locking system on the first pair of edges are formed at least of a locking part on the lower side of the tongue and a locking part on the aforementioned lower lip, which, by means of contact surfaces, which can cooperate with each other, result in the respective locking; and wherein the coupling parts on the first pair of edges in the coupled condition show one or both of the following characteristics: in the direction of the distal extremity of the tongue, at the same height (H) as the aforementioned contact surfaces, a free space is present between the tongue and the opposite floor panel; the cooperation of the aforementioned contact surfaces defines a tangent line which, in respect to the horizontal, forms an angle of at least 40 degrees.

33. The floor panel of claim 32, wherein the elastic force is delivered in that the coupling parts are configured such that the locking parts on tongue and groove during the turning movement can pass alongside each other exclusively be exerting a force.

34. The floor panel of claim 32, wherein the elastic force substantially is the result of an elastic bending in the lower lip.

35. The floor panel of claim 32, wherein the locking elements of the hook-shaped parts comprise locking surfaces, which provide for the horizontal locking and determine a tangent line, which either is directed inward, and they manifest themselves as an undercut, or define a tangent line which is standing perpendicular to the plane of the floor panels, or define a tangent line which is directed outward, however, in the last case with an angle of maximum 30 degrees in respect to the vertical.

36. The floor panel of claim 32, wherein the locking part of the second locking system, which is situated on the distal extremity of the lower hook-shaped part, and/or the corresponding locking part on the other edge, massively form part of the coupling parts or the floor panels, or at least are massively supported directly towards the back, such over the majority of the length of the edge concerned.

37. The floor panel of claim 32, wherein instead of the fact that the distal extremity of the upper hook-shaped part and the side situated opposite thereto in the coupled condition of two floor panels, are free from vertically locking parts, now indeed such locking parts are present; however, that the formed locking surfaces thereof, in the coupled condition, are situated entirely above a horizontal level, which is determined by the highest point of the upward-directed locking part of the lower hook-shaped part.

38. The floor panel of claim 32, wherein this floor panel substantially is realized on the basis of synthetic material and as a layer-shaped substrate.

39. The floor panel of claim 38, wherein it is a floor panel of the supple type of the “resilient floor” type.

40. The floor panel of claim 32, wherein it substantially consists of a laminate panel with a substrate of MDF or HDF, or consists of an engineered-wood floor panel.

41. A floor panel for forming a floor covering, wherein this floor panel is rectangular and oblong and comprises: a first pair of opposite edges, which form the long edges of the floor panel, and a second pair of opposite edges, which form the short edges of the floor panel; wherein both pairs of opposite edges comprise coupling parts, which allow that a plurality of such floor panels mutually can be coupled to each other; wherein these coupling parts, on both pairs of edges, form a first locking system, which, in a coupled condition of two of such floor panels, effects a locking in the plane of the floor panels and perpendicular to the respective edges, and form a second locking system, which, in a coupled condition of two of such floor panels, effects a locking transverse to the plane of the floor panels; wherein these coupling parts on the first pair of opposite edges substantially are realized in the material of the floor panel itself; wherein the coupling parts of at least the first pair of opposite edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a turning movement and to this aim these coupling parts on the first pair of opposite edges consist of a tongue and a groove, and of locking parts, which, in the coupled condition, prevent the shifting apart of the tongue and groove; wherein on the first pair of opposite edges the groove is bordered by a lower lip and an upper lip, of which the lower lip extends laterally up to beyond the distal extremity of the upper lip; wherein the coupling parts on the second pair of edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a downward movement of one floor panel in respect to the other, such that a plurality of such floor panels can be coupled to each other by means of a “fold-down” technique; wherein the first locking system of the second pair of edges is at least formed of an upward-directed lower hook-shaped part, which is situated on one of said two edges and which comprises a distal extremity, and a downward-directed upper hook-shaped part, which is situated on the opposite edge, wherein the lower hook-shaped part consists of a lip with an upward-directed locking element, whereas the upper hook-shaped part consists of a lip with a downward-directed locking element; wherein the second locking system of the second pair of edges is at least formed by a locking part, which is situated on the distal extremity of the lower hook-shaped part, and a locking part, which cooperates therewith in the coupled condition of two of such floor panels, on the edge which comprises the upper hook-shaped part; wherein the distal extremity of the upper hook-shaped part and the side which, in coupled condition, is opposite thereto, are free from mutually vertically locking portions; and wherein the coupling parts on the first pair of edges are configured such that the floor panels on this first pair of edges, in the final coupled condition of two of such floor panels, are coupled in horizontal direction with a tensioning force which presses the floor panels at their upper edges substantially permanently towards each other by “pre-tension,”, which tensioning force is built up during the turning in.

42. The floor panel of claim 41, wherein the aforementioned locking parts of the first locking system on the first pair of edges are formed at least by a locking part on the lower side of the tongue and a locking part on said lower lip, which provide for the respective locking via contact surfaces, which can cooperate with each other.

43. The floor panel of claim 41, wherein the tensioning force is at least the result of a configuration which provides for that the lower lip is elastically bent out in the final coupled condition.

44. The floor panel of claim 41, wherein the coupling parts on the first pair of edges in the coupled condition show the characteristic that, in the direction of the distal extremity of the tongue, at the same height as said contact surfaces, a free space is present between the tongue and the opposite floor panel, and/or that the cooperation of said contact surfaces define a tangent line which, in respect to the horizontal, forms an angle of at least 40 degrees.

45. The floor panel of claim 41, wherein the locking elements of the hook-shaped parts comprise locking surfaces, which provide for the horizontal locking and determine a tangent line, which either is directed inward, and they manifest themselves as an undercut, or define a tangent line which is standing perpendicular to the plane of the floor panels, or define a tangent line which is directed outward, however, in the last case with an angle of maximum 30 degrees in respect to the vertical.

46. The floor panel of claim 41, wherein the locking part of the second locking system, which is situated on the distal extremity of the lower hook-shaped part, and/or the corresponding locking part on the other edge, massively form part of the coupling parts or the floor panels, or at least are massively supported directly towards the back, such over the majority of the length of the edge concerned.

47. The floor panel of claim 41, wherein instead of the fact that the distal extremity of the upper hook-shaped part and the side situated opposite thereto in the coupled condition of two floor panels, are free from vertically locking parts, now indeed such locking parts are present; wherein the formed locking surfaces thereof, in the coupled condition, are situated entirely above a horizontal level, which is determined by the highest point of the upward-directed locking part of the lower hook-shaped part.

48. The floor panel of claim 41, wherein this floor panel substantially is realized on the basis of synthetic material and as a layer-shaped substrate.

49. The floor panel of claim 48, wherein it is a floor panel of the supple of a “resilient floor” type.

50. The floor panel of claim 41, wherein it substantially consists of a laminate panel with a substrate of MDF or HDF, or consists of an engineered-wood floor panel.

51. A floor panel for forming a floor covering, wherein this floor panel is rectangular and oblong and comprises: a first pair of opposite edges, which form the long edges of the floor panel, and comprises a second pair of opposite edges, which form the short edges of the floor panel; wherein both pairs of opposite edges comprise coupling parts, which allow that a plurality of such floor panels mutually can be coupled to each other; wherein these coupling parts, on both pairs of edges, form a first locking system, which, in a coupled condition of two of such floor panels, effects a locking in the plane of the floor panels and perpendicular to the respective edges, and form a second locking system, which, in a coupled condition of two of such floor panels, effects a locking transverse to the plane of the floor panels; wherein these coupling parts on the first pair of opposite edges substantially are realized in the material of the floor panel itself; wherein the coupling parts of at least the first pair of opposite edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a turning movement and to this aim these coupling parts on the first pair of opposite edges consist of a tongue and a groove, and locking parts, which, in the coupled condition, prevent the shifting apart of the tongue and groove; wherein on the first pair of opposite edges the groove is bordered by a lower lip and an upper lip, of which the lower lip extends laterally up to beyond the distal extremity of the upper lip; wherein the coupling parts on the second pair of edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a downward movement of one floor panel in respect to the other, such that a plurality of such floor panels can be coupled to each other by a “fold-down” technique; wherein the first locking system of the second pair of edges is at least formed of an upward-directed lower hook-shaped part, which is situated on one of said two edges and which comprises a distal extremity, and a downward-directed upper hook-shaped part, which is situated on the opposite edge, wherein the lower hook-shaped part consists of a lip with an upward-directed locking element, whereas the upper hook-shaped part consists of a lip with a downward-directed locking element; wherein the second locking system of the second pair of edges is at least formed by a locking part, which is situated on the distal extremity of the lower hook-shaped part, and a locking part, which cooperates therewith in the coupled condition of two of such floor panels, on the edge which comprises the upper hook-shaped part; wherein the distal extremity of the upper hook-shaped part and the side which, in coupled condition, is opposite thereto, are free from mutually vertically locking portions; and wherein the coupling parts on the first pair of edges are configured such that they allow a tensionless turning into each other up into the final coupled condition, without building up a pre-tension, or without having to overcome a temporary elastic force.

52. The floor panel of claim 51, wherein the floor panels on the first pair of edges, in the final coupled condition of two of such floor panels, are coupled in horizontal direction free from play or, if such play indeed is present, it is less than 0.2 mm.

53. The floor panel of claim 51, wherein the aforementioned locking parts of the first locking system on the first pair of edges are formed at least by a locking part on the lower side of the tongue and a locking part on said lower lip, which provide for the respective locking via contact surfaces, which can cooperate with each other.

54. The floor panel of claim 51, wherein the coupling parts on the first pair of edges in the coupled condition show the characteristic that, in the direction of the distal extremity of the tongue, at the same height as the aforementioned contact surfaces, a free space is present between the tongue and the opposite floor panel, and/or that the cooperation of the aforementioned contact surfaces defines a tangent line, which, in respect to the horizontal, forms an angle of at least 40 degrees.

55. The floor panel of claim 51, wherein the locking elements of the hook-shaped parts comprise locking surfaces, which provide for the horizontal locking and determine a tangent line, which either is directed inward, and they manifest themselves as an undercut, or define a tangent line which is standing perpendicular to the plane of the floor panels, or define a tangent line which is directed outward, however, in the last case with an angle of maximum 30 degrees in respect to the vertical.

56. The floor panel of claim 51, wherein the locking part of the second locking system, which is situated on the distal extremity of the lower hook-shaped part, and/or the corresponding locking part on the other edge, massively form part of the coupling parts or the floor panels, or at least are massively supported directly towards the back, such over the majority of the length of the edge concerned.

57. The floor panel of claim 51, wherein instead of the fact that the distal extremity of the upper hook-shaped part and the side situated opposite thereto in the coupled condition of two floor panels, are free from vertically locking parts, now indeed such locking parts are present; the formed locking surfaces thereof, in the coupled condition, are situated entirely above a horizontal level, which is determined by the highest point of the upward-directed locking part of the lower hook-shaped part.

58. The floor panel of claim 51, wherein this floor panel substantially is realized on the basis of synthetic material and as a layer-shaped substrate.

59. The floor panel of claim 58, wherein it is a floor panel of the supple type of a “resilient floor” type.

60. The floor panel of claim 51, wherein it substantially consists of a laminate panel with a substrate of MDF or HDF or of an engineered-wood floor panel.

Description

[0068] 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:

[0069] FIG. 1 schematically represents a part of a floor covering, which is realized by means of floor panels according to the invention, and in which the fold-down principle is shown schematically;

[0070] FIG. 2 represents the coupling parts on the short edges;

[0071] FIGS. 3 and 4 illustrate the coupling parts on the long sides for an embodiment according to the first aspect of the invention, in a condition during coupling and in a completely coupled condition, respectively;

[0072] FIGS. 5 and 6 illustrate the coupling parts on the long sides for an embodiment according to the second aspect of the invention, in a condition during coupling and in a completely coupled condition, respectively;

[0073] FIGS. 7 and 8 illustrate the coupling parts on the long sides for an embodiment according to the third aspect of the invention, in a condition during coupling and in a completely coupled condition, respectively.

[0074] FIGS. 1 to 4 illustrate the first aspect of the invention, wherein FIG. 1 is a schematic representation of the floor covering, FIG. 2 in cross-section represents a possible embodiment of the short edges, whereas FIGS. 3 and 4 in not-crosshatched form illustrate cross-sections of the long sides or edges, in a condition during coupling and in a completely coupled condition, respectively.

[0075] As is represented in FIGS. 1 to 4, the invention, according to its first aspect, provides for a floor panel for forming a floor covering, wherein this floor panel 1 is rectangular and oblong and thus comprises a first pair of opposite edges 2-3, which form the long edges of the floor panel, as well as comprises a second pair of opposite edges 4-5, which form the short edges of the floor panel; wherein both pairs of opposite edges 2-3, 4-5 comprise coupling parts 6-7, 8-9, which allow that a plurality of such floor panels 1 mutually can be coupled to each other; wherein these coupling parts 6-7, 8-9, respectively, on both pairs of edges 2-3 and 4-5, form a first locking system, which, in a coupled condition of two of such floor panels, effects a locking in the plane of the floor panels and perpendicular to the respective edges, as well as form a second locking system, which, in a coupled condition of two of such floor panels, effects a locking transverse to the plane of the floor panels; wherein these coupling parts 6-7 on the first pair of opposite edges substantially are realized in the material of the floor panel itself; wherein the coupling parts of at least the first pair of opposite edges 2-3 are configured such that two of such floor panels 1 can be coupled to each other at these edges by means of a turning movement and to this aim these coupling parts 6-7 on the first pair of opposite edges consist of a tongue 10 and a groove 11, as well as of locking parts 12-13, which, in the coupled condition, prevent the shifting apart of the tongue and groove; wherein on the first pair of opposite edges the groove is bordered by a lower lip 14 and an upper lip 15, of which the lower lip 14 extends laterally up to beyond the distal extremity 16 of the upper lip; wherein the coupling parts on the second pair of edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a downward movement 17 of one floor panel in respect to the other, more particularly such that a plurality of such floor panels can be coupled to each other by means of the so-called “fold-down” technique; wherein the first locking system of the second pair of edges is at least formed of an upward-directed lower hook-shaped part 18, which is situated on one of said two edges, in this case edge 5, and which comprises a distal extremity, as well as a downward-directed upper hook-shaped part 19, which is situated on the opposite edge 4, wherein the lower hook-shaped part 18 consists of a lip 20 with an upward-directed locking element 21, whereas the upper hook-shaped part 19 consists of a lip 22 with a downward-directed locking element 23; wherein the second locking system of the second pair of edges is at least formed by a locking part 24, which is situated on the distal extremity of the lower hook-shaped part, as well as a locking part 25, which cooperates therewith in the coupled condition of two of such floor panels, on the edge 4 which comprises the upper hook-shaped part 19; and wherein the distal extremity 26 of the upper hook-shaped part and the side 27 which, in coupled condition, is opposite thereto, are free from mutually vertically locking parts. The floor panel 1 has the characteristic that the coupling parts on the first pair of edges are configured such that during the turning into each other of two of such floor panels an elastic force has to be overcome during the turning movement, which force, during the turning into each other, first increases in order to subsequently decrease again; that the floor panels on the first pair of edges, in the final coupled condition of two of such floor panels, are coupled in horizontal direction free from play, or, if such play indeed exists, this play is less than 0.2 mm; that the aforementioned locking parts of the first locking system on the first pair of edges are formed at least of a locking part on the lower side of the tongue and a locking part on the aforementioned lower lip, which, by means of contact surfaces 28-29, which can cooperate with each other, result in the respective locking; and that the coupling parts on the first pair of edges in the coupled condition show one or both of the following characteristics: [0076] in the direction of the distal extremity of the tongue, at the same height H as the aforementioned contact surfaces 28-29, a free space 30 is present between the tongue and the opposite floor panel; [0077] the cooperation of the aforementioned contact surfaces defines a tangent line T1 which, in respect to the horizontal, forms an angle of at least 40 degrees, such in the direction as represented in the figures, in other words, seen from bottom to top outwardly inclined.

[0078] Herein, it is noted that the groove 11 has to be considered as the entire space which is situated between the distal extremity of the upper lip 16 and the distal extremity of the lower lip 14. By the herein above-mentioned term “tongue” thus the entire part cooperating therewith has to be understood. In other words, this means that the locking part 12 has to be considered a component of the tongue 10. The represented space 30, which is situated at the aforementioned height H distally in front of the locking part 12, thus by definition forms an example of “a free space 30 which is present at the height H between the tongue and the opposite floor panel”.

[0079] FIG. 3 schematically shows that the aforementioned elastic force is supplied in that the coupling parts 6-7 are configured such that the locking parts 12 and 13 on tongue and groove, during the turning movement, can pass alongside each other exclusively by exertion of a force. Hereby, it becomes clear from this figure that in the represented example the elastic force at least, and in this case substantially, is the result of an elastic bending in the lower lip 14.

[0080] It is clear that in the further movement from the position represented in FIG. 3 into the position of FIG. 4, the lower lip 14 springs back, whereby the elastic force decreases. In the final condition, which is represented in FIG. 4, the lower lip 14 again is in a not elastically bent-out condition; however, it is clear that according to a variant in the end position also an elastic bending out of the lower lip 14 might remain, which usually then in fact is smaller than in the condition of FIG. 3.

[0081] It is also clear that during the turning movement of FIG. 3 the floor panels preferably contact each other in the proximity of their upper edge.

[0082] Due to the elastic force which manifests itself at least during a part of the aforementioned turning movement, at least during this part a certain tensioning force is created among the coupling parts 6-7. This has the consequence that, when the coupling parts 6-7 should have the tendency of mutually shifting in the longitudinal direction of the respective edges, a friction force must be overcome. This effect results in that the risk of such longitudinal shifting, which may occur as a result of the fact that the locking parts 24 and 25 are forced alongside each other during the fold-down movement, is minimized.

[0083] In FIGS. 5 and 6 schematically a variant of the coupling parts 8 and 9 is represented, which are configured such that, combined with an embodiment of the edges 2-3 according to FIG. 2, a floor panel 1 is obtained which fulfills the second aspect of the invention. Herein, then in fact a floor panel for forming a floor covering is provided, wherein this floor panel 1 is rectangular and oblong and thus comprises a first pair of opposite edges 2-3, which form the long edges of the floor panel, as well as comprises a second pair of opposite edges 4-5, which form the short edges of the floor panel; wherein both pairs of opposite edges 2-3 and 4-5 comprise coupling parts 6-7 and 8-9, which allow that a plurality of such floor panels 1 mutually can be coupled to each other; wherein these coupling parts 6-7 and 8-9 on both pairs of edges 2-3 and 4-5 form a first locking system, which, in a coupled condition of two of such floor panels, effects a locking in the plane of the floor panels and perpendicular to the respective edges, thus, horizontally, as well as form a second locking system, which, in a coupled condition of two of such floor panels, effects a locking transverse to the plane of the floor panels, thus, vertically; wherein these coupling parts 6-7 on the first pair of opposite edges substantially are realized in the material of the floor panel itself; wherein the coupling parts of at least the first pair of opposite edges 2-3 are configured such that two of such floor panels 1 can be coupled to each other at these edges by means of a turning movement and to this aim these coupling parts 6-7 on the first pair of opposite edges consist of a tongue 10 and a groove 11, as well as of locking parts 12-13, which, in the coupled condition, prevent the shifting apart of the tongue and groove; wherein on the first pair of opposite edges the groove is bordered by a lower lip 14 and an upper lip 15, of which the lower lip 14 extends laterally up to beyond the distal extremity 16 of the upper lip; wherein the coupling parts on the second pair of edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a downward movement 17 of one floor panel in respect to the other, more particularly such that a plurality of such floor panels can be coupled to each other by means of the so-called “fold-down” technique; wherein the first locking system of the second pair of edges is at least formed of an upward-directed lower hook-shaped part 18, which is situated on one of said two edges 5 and which comprises a distal extremity, as well as a downward-directed upper hook-shaped part 19, which is situated on the opposite edge 4, wherein the lower hook-shaped part 18 consists of a lip 20 with an upward-directed locking element 21, whereas the upper hook-shaped part 19 consists of a lip 22 with a downward-directed locking element 23; wherein the second locking system of the second pair of edges is at least formed by a locking part 24, which is situated on the distal extremity of the lower hook-shaped part, as well as a locking part 25, which cooperates therewith in the coupled condition of two of such floor panels, on the edge which comprises the upper hook-shaped part; and wherein the distal extremity 26 of the upper hook-shaped part and the side 27 which, in coupled condition, is opposite thereto, are free from mutually vertically locking parts; with the particularity that the coupling parts on the first pair of edges are configured such that the floor panels on this first pair of edges in the final coupled condition of two of such floor panels in horizontal direction are coupled with a tensioning force F, which presses the floor panels at their upper edges substantially permanently towards each other, more particularly a so called “pre-tension”, which tensioning force F is built up during the turning in.

[0084] As represented in FIGS. 5 and 6, the aforementioned locking parts of the first locking system on the first pair of edges are at least formed of a locking part 12 on the lower side of the tongue 10 and a locking part 13 on the aforementioned lower lip 14, which provide for the respective locking via contact surfaces 28-29, which can cooperate with each other.

[0085] The tensioning force is at least the result of a configuration which provides for that the lower lip 14 is elastically bent out in the final coupled condition, such as illustrated by means of FIG. 6.

[0086] It is clear that the coupling parts 6-7 can be configured such that the tensioning force permanently increases until the coupled condition is reached. According to another possibility, the tensioning force, during the turning in, also can go over a peak in order to finally still retain a permanent tension. It is clear that the tensioning force offers the same advantage as in an embodiment according to the first aspect.

[0087] FIG. 6 shows that the coupling parts on the first pair of edges in the coupled condition show the characteristic that in the direction of the distal extremity of the tongue, at the same height H as the aforementioned contact surfaces, a free space 30 is present between the tongue, including the locking part, and the opposite floor panel, and that the cooperation of the aforementioned contact surfaces defines a tangent line T1, which forms an angle of at least 40 degrees in respect to the horizontal. These characteristics promote and/or optimize the pre-tension effect.

[0088] In FIGS. 7 and 8, schematically a variant is represented of the coupling parts 8 and 9, which are configured such that, combined with an embodiment of the edges 2-3 according to FIG. 2, a floor panel 1 is obtained which fulfills the third aspect of the invention. Herein, in fact a floor panel for forming a floor covering is provided, wherein this floor panel 1 is rectangular and oblong and thus comprises a first pair of opposite edges 2-3, which form the long edges of the floor panel, as well as comprises a second pair of opposite edges 4-5, which form the short edges of the floor panel; wherein both pairs of opposite edges 2-3 and 4-5 comprise coupling parts 6-7 and 8-9, which allow that a plurality of such floor panels 1 mutually can be coupled to each other; wherein these coupling parts 6-7 and 8-9, on both pairs of edges 2-3 and 4-5, form a first locking system, which, in a coupled condition of two of such floor panels, effects a locking in the plane of the floor panels and perpendicular to the respective edges, as well as form a second locking system, which, in a coupled condition of two of such floor panels, effects a locking transverse to the plane of the floor panels; wherein these coupling parts 6-7 on the first pair of opposite edges substantially are realized in the material of the floor panel itself; wherein the coupling parts of at least the first pair of opposite edges 2-3 are configured such that two such floor panels 1 can be coupled to each other at these edges by means of a turning movement and to this aim these coupling parts 6-7 on the first pair of opposite edges consist of a tongue 10 and a groove 11, as well as of locking parts 12-13, which, in the coupled condition, prevent the shifting apart of the tongue and groove; wherein on the first pair of opposite edges the groove is bordered by a lower lip 14 and an upper lip 15, of which the lower lip 14 extends laterally up to beyond the distal extremity 16 of the upper lip; wherein the coupling parts on the second pair of edges are configured such that two of such floor panels can be coupled to each other at these edges by means of a downward movement of one panel in respect to the other, more particularly such that a plurality of such floor panels can be coupled to each other by means of the so-called “fold-down” technique; wherein the first locking system of the second pair of edges is at least formed of an upward-directed lower hook-shaped part 18, which is situated on one of said two edges 5 and which comprises a distal extremity, as well as a downward-directed upper hook-shaped part or element 19, which is situated on the opposite edge 4, wherein the lower hook-shaped part 18 consists of a lip 20 with an upward-directed locking element 21, whereas the upper hook-shaped part 19 consists of a lip 22 with a downward-directed locking element 23; wherein the second locking system of the second pair of edges is at least formed by a locking part 24, which is situated on the distal extremity of the lower hook-shaped part, as well as a locking part 25, which cooperates therewith in the coupled condition of two of such floor panels, on the edge which comprises the upper hook-shaped part; wherein the distal extremity 26 of the upper hook-shaped part and the side 27 which, in coupled condition, is opposite thereto, are free from mutually vertically locking parts, with the particularity that the coupling parts on the first pair of edges are configured such that they allow a tensionless turning into each other up into the final coupled condition, more particularly without building up a so-called pre-tension, or without having to overcome a temporary elastic force.

[0089] By making use of a configuration of coupling parts 6-7 which turn into each other tensionless, a self-searching effect is created at the short edges, such that it can also be expected in this manner that the short edges end up in each other in a proper manner.

[0090] Herein, it is preferred that the floor panels at the first pair of edges in the final coupled condition of two of such floor panels are coupled free from play in the horizontal direction or, when such play indeed exists, this is less than 0.2 mm. Here, this relates to the condition at the upper edges, where the floor panels adjoin each other. In the case of floor panels with bevels, this, of course, is the location where the lower edges of the bevels adjoin each other.

[0091] In the embodiment of FIGS. 7 and 8, too, the aforementioned locking parts of the first locking system on the first pair of edges are formed at least by a locking part on the lower side of the tongue and a locking part on the aforementioned lower lip, which provide for the respective locking via contact surfaces, which can cooperate with each other.

[0092] In this example, too, the floor panels 1 are characterized in that the coupling parts on the first pair of edges in the coupled condition show the characteristic that in the direction of the distal extremity of the tongue, at the same height H as the aforementioned contact surfaces, a free space 30 is present between the tongue, including the locking part, and the opposite floor panel, and that the cooperation of the aforementioned contact surfaces define a tangent line T1, which forms an angle of at least 40 degrees in respect to the horizontal.

[0093] It is noted that in the embodiment of FIG. 2, the locking elements of the hook-shaped parts comprise locking surfaces, which provide for the horizontal locking and which have a tangent line T2, which is situated perpendicular to the plane of the floor panels. Alternatively, these locking surfaces also can be realized such that the tangent line in upward direction is inwardly or outwardly inclined, for example, within an angle range as indicated by B in FIG. 2. If the tangent line is outwardly directed, the angle A preferably is maximum 30 degrees.

[0094] FIG. 2 also illustrates that the locking part of the second locking system, which is situated on the distal extremity of the lower hook-shaped part, and the corresponding locking part on the other edge massively form part of the coupling parts or the floor panels, or at least are massively supported directly towards the back, and thus no grooves or the like are present there behind which have the purpose of creating movable parts, such over the majority of the length of the edge concerned.

[0095] According to deviating variants of the first, second and third aspect, the invention also relates to floor panels which are characterized in that, instead of the fact that the distal extremity of the upper hook-shaped part and the side situated opposite thereto in the coupled condition of two floor panels, are free from vertically locking parts, now indeed such locking parts 31-32 are present. This alternative is represented in dashed line in FIG. 2. In other words, this means that the invention also relates to three deviating aspects, wherein each time all characteristics of the first, second and third aspect are applied, with the exception of the fact that now indeed locking parts 31 and 32 are present on the edges concerned.

[0096] Herein, it is preferred that the locking surfaces formed thereby, thus, of the locking parts 31 and 32, in the coupled condition, are situated entirely above a horizontal level N, which is determined by the highest point of the upward-directed locking part of the lower hook-shaped part.

[0097] It is noted that generally it is valid that contact surfaces and locking surfaces do not have to be flat, however, may also be curved, thus, consist of curved surfaces.

[0098] FIGS. 3 to 8 also illustrate the characteristic that the aforementioned locking parts of the first pair of edges are provided with locking contact surfaces 28-29, which in the coupled condition are situated at least partially in the portion of the lower lip 14 which is situated beyond the distal extremity 16 of the upper lip 15.

[0099] FIG. 2 also illustrates the characteristic that the coupling parts on the second pair of edges are made in one piece from the material of the floor panels, preferably in the form of milled profiled parts.

[0100] The invention is primarily intended for synthetic floors, as described in the claims and the introduction, however, can also be applied with other floor panels.

[0101] It is noted that the locking parts 24-25 may have any form, as long as they provide for a vertical locking. The same is valid for the locking parts 31-32.

[0102] Further, it is noted that behind the distal extremity of the lower lip 14 preferably a free space is present, such that the distal side of the distal extremity is free.

[0103] According to an invention not included in the claims, a fold-down system is provided, with the characteristic that the coupling parts on the short sides provide for a vertical locking which is of such nature that the locking can be pulled apart vertically, in a non-damaging manner, by means of a de-folding movement. Starting from this fact, the form of the coupling parts can be determined by testing. It is clear that this can be realized in combination with the three independent aspects of the invention.

[0104] The present invention is in no way limited to the embodiments described by way of example and represented in the figures; on the contrary, such floor panels, and more particularly the coupling parts thereof, can be realized in various forms and dimensions, without leaving the scope of the invention.