Mechanical locking system for floor panels

Abstract

Floor panels are shown, which are provided with a vertical locking system on short edges comprising a displaceable tongue that is displaced in one direction into a tongue groove during vertical displacement of two panels. The displaceable tongue may be provided in a sidewardly open displacement groove at an edge of a building panel, the displaceable tongue including a main body extending along the edge of the panel and a tongue locking surface located at an upper and outer part of the tongue.

Claims

1. Building panels provided with a locking system for vertical locking of a first and a second building panel by a vertical displacement of the panels relative to each other, wherein juxtaposed upper parts of adjacent joint edges of the first and second building panels in a locked position define a vertical plane, and wherein the building panels comprise: a strip on said first building panel and protruding outwardly from the vertical plane and beyond an upper part of an edge of said first building panel, and a displaceable tongue provided in a sidewardly open displacement groove at an edge of the second building panel, wherein the displaceable tongue comprises a flexible part configured to cooperate with the strip such that the displaceable tongue is displaced from a position out of a tongue groove provided at the edge of said first building panel and above a lowest part of an upper surface of the strip to a position in the tongue groove when the first building panel and the second building panel are displaced vertically relative to each other to obtain a locking of the first building panel and the second building panel in a vertical direction, and wherein the flexible part creates a pre-tension against the tongue groove in an installed state of the first building panel and the second building panel.

2. The building panels as claimed in claim 1, wherein the flexible part is provided inwardly of an upper part of the edge of the second building panel in the installed state of the first building panel and the second building panel.

3. The building panels as claimed in claim 1, wherein said flexible part is provided on a protrusion extending in a transverse direction from a main body of the displaceable tongue.

4. The building panels as claimed in claim 3, wherein the second building panel comprises a cavity for housing the protrusion.

5. The building panels as claimed in claim 3, wherein the main body of the displaceable tongue has a length along the edge of the second building panel in a horizontal direction, and the protrusion has a length along the edge of the second building panel in the horizontal direction, and the length of the protrusion is less than the length of the main body.

6. The building panels as claimed in claim 3, wherein the displaceable tongue has a tongue locking surface that contacts a groove locking surface of the tongue groove for vertical locking of the first building panel and the second building panel, and the tongue locking surface and the groove locking surface are congruently inclined.

7. The building panels as claimed in claim 4, wherein the cavity is larger than the protrusion.

8. The building panels as claimed in claim 4, wherein the strip comprises a locking element configured to cooperate with a locking groove formed on the second building panel, for locking the first building panel and the second building panel in a horizontal direction, and the cavity extends from the sidewardly open displacement groove into the locking groove.

9. The building panels as claimed in claim 1, wherein the flexible part is S-shaped in a plane coinciding with an upper part of the displaceable tongue.

10. The building panels as claimed in claim 1, wherein a width of the flexible part in a longitudinal direction of the displaceable tongue varies along a transverse direction of the flexible part.

11. The building panels as claimed in claim 1, wherein a transverse length of the flexible part varies along a longitudinal direction of the displaceable tongue.

12. The building panels as claimed in claim 1, wherein the flexible part is flexible in a direction transverse to a longitudinal direction of the displaceable tongue.

13. The building panels as claimed in claim 1, wherein the displaceable tongue is configured to be displaced at an angle with respect to a horizontal plane extending parallel to a surface layer of the second building panel.

14. The building panels as claimed in claim 13, wherein the displaceable tongue is configured to be displaced obliquely upwards into the tongue groove during locking of the first building panel and the second building panel.

15. The building panels as claimed in claim 1, wherein the flexible part extends along a part of the displaceable tongue in a longitudinal direction of the displaceable tongue.

16. The building panels as claimed in claim 1, wherein the flexible part comprises a tongue pressing surface which is configured to cooperate with a strip pressing surface on the strip.

17. The building panels as claimed in claim 16, wherein the strip pressing surface is provided vertically below a groove locking surface of the tongue groove.

18. The building panels as claimed in claim 16, wherein the tongue pressing surface is located vertically below a tongue locking surface of the displaceable tongue with the tongue groove.

19. The building panels as claimed in claim 1, wherein there is a space between a lower and outer part of the displaceable tongue and a lower part of the tongue groove.

20. The building panels as claimed in claim 19, wherein said space is provided along an entirety of the edges of the first building panel and the second building panel in the installed state of the first building panel and the second building panel.

21. The building panels as claimed in claim 1, wherein a portion of the displaceable tongue is fixed in the sidewardly open displacement groove with a friction connection.

22. The building panels as claimed in claim 1, wherein said flexible part is provided on at least two protrusions extending in a transverse direction from a main body of the displaceable tongue.

23. The building panels as claimed in claim 1, wherein an innermost part of the displaceable tongue is provided vertically below an outermost part of the displaceable tongue in the installed state of the first building panel and the second building panel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The disclosure will in the following be described in connection to exemplary embodiments and in greater detail with reference to the appended exemplary drawings, wherein:

(2) FIGS. 1a-f illustrate locking systems according to known technology.

(3) FIGS. 2a-d illustrate a short edge locking system according to an embodiment of the disclosure.

(4) FIGS. 3a-3d illustrate a short edge locking system according to preferred embodiments of the disclosure.

(5) FIGS. 4a-e illustrate preferred embodiments of short edge locking systems.

(6) FIGS. 5a-e illustrate vertical folding of three panels according to an embodiment of the disclosure.

(7) FIGS. 6a-e illustrate the flexibility of the locking systems during locking and preferred embodiments of displaceable tongues.

(8) FIGS. 7a-b illustrate tongue blanks according to embodiments of the disclosure comprising several displaceable tongues.

DESCRIPTION OF EMBODIMENTS OF THE DISCLOSURE

(9) To facilitate understanding, several locking systems in the figures are shown schematically. It should be emphasized that improved or different functions may be achieved using combinations of the preferred embodiments.

(10) All embodiments may be used separately or in combinations. Angles, dimensions, rounded parts, spaces between surfaces etc. are only examples and may be adjusted within the basic principles of the disclosure.

(11) FIGS. 2a-2d show a first preferred embodiment of a short edge locking system provided with a flexible and displaceable tongue 30 in an edge of a second panel 1 inserted in a displacement groove 40 and extending along the edge of the second panel. The displaceable tongue 30 has a tongue locking surface 31 located at an upper and outer part that cooperates with a groove locking surface 21 located at an inner and upper part of a tongue groove 20 formed in an adjacent edge of a first panel 1. The locking surfaces lock the panels in a first vertical direction. The locking surfaces are preferably inclined with an angle A2 that is about 10-60 degrees. The displacement groove is preferably also inclined and the outer part is closer to the panel surface than an inner part.

(12) The first panel 1 comprises a protruding strip 6 that extends outwardly beyond a vertical plane VP. The strip comprises a locking element 8. The second panel 1 comprises a locking groove 14 that cooperates with the locking element 8 and locks the panels in a horizontal direction. The strip 6 has an upper part 6, which is in contact with a lower part 37 of the adjacent edge and locks the panels in a second vertical direction.

(13) The displaceable tongue 30 comprises a protrusion 34 extending from a main tongue body 36. The second panel 1 comprises at least one cavity 35 for housing the protrusion. The cavity extends from the displacement groove to the locking groove 14.

(14) The cavity may be formed by a screw cutter or by displaceable saw blades.

(15) The protrusion comprises a tongue pressing surface 32 which cooperates with a strip pressing surface 33 on the locking element. The strip pressing surface 33 and the tongue pressing surface 32 are inclined with an angle A1 which is preferably 25-75 degrees against a horizontal plane HP.

(16) The displaceable tongue is displaced essentially in one direction towards the tongue groove when the inclined pressing surfaces are sliding against each other during the vertical displacement of the adjacent edges. The tongue may be locked with a strong pressure against the tongue groove 21 and the locking element 14 prevents the tongue from sliding back into the displacement groove.

(17) One major problem related to a press lock system as described above is the risk that they may split with a crack 50 between the displacement groove 40 and the locking groove 14 as shown in FIG. 2d. Therefore it is preferable that the upper parts of the locking groove 14a and the locking element 8a are made in the lower part of the floor panel, preferably below the center line C that divides the floor panel in two equal parts, one upper part UP and one lower part LP. It is also preferable that the tongue pressing surface 32 is located vertically below the tongue locking surface 31. The tongue pressing surface and the tongue locking surface are preferably offset vertically and are preferably located on different horizontal planes H2, H1. It is also preferred that an upper part of the locking element 8a and/or an upper part of the locking groove 14a are located vertically below the tongue locking surface 31. The innermost part of the displaceable tongue 30 is preferably located below the outermost part of such tongue.

(18) The cavities 35 are preferably formed by rotating saw blades and comprise preferably an upper rounded part with an outer part 35b that is located above an inner part 35a as shown in FIG. 2d. The cavity is preferably formed such that it intersects the inner part 14b of the locking groove 14.

(19) FIGS. 3a-3d show the locking function during the vertical displacement of the second panel 1 against the first panel 1. The displaceable tongue 30 is gradually pressed into the tongue groove 20 by the cooperating pressing surfaces 32,33 and the panels are locked vertically with two pairs of cooperating locking surfaces, the tongue locking surface 31 and the groove locking surface 21 and an upper part 6 of the strip 6 and a lower part 37 of the adjacent edge 1.

(20) FIGS. 4a-4e show different embodiments. FIG. 4a shows a displaceable tongue 30 with a protrusion 34 located under the main tongue body. The locking groove 14 is located vertically under an upper part of the displacement groove 40. FIG. 4b shows a tongue pressing surface 32 that locks against a strip pressing surface that is not active in the horizontal locking. FIG. 4c shows that the same locking surface 33 on the locking element 8 may be used as a pressing surface and as a locking surface for the horizontal locking. FIG. 4d shows that the strip pressing surface may be formed on a separate pushing rod 42. FIG. 4e shows a protrusion 34 that comprises a curved cross section and a locking element that comprises an upper part 44 formed as local protrusion that protrudes above the inner part of the locking groove 14 and into the cavities 35.

(21) FIGS. 5a-5e show vertical folding of three panels wherein the long edges 2,2 are connected with angling and the short edges 1, 1 with a scissor like motion that combines angling and vertical displacement. FIG. 5b shows that the displaceable tongue is gradually inserted into the tongue groove 20 from one part of the edges that is adjacent to the installed long edge 2 to the other free long edge. FIG. 5c shows the tongue in the cross section A-A and FIGS. 5d, 5e show the tongue position in the cross sections B-B, and C-C. The strip 6 and the locking element 8 are in this embodiment designed such that they bend backwards during locking and this facilitates locking since the necessary flexibility may be provided partly or completely with such strip bending. The locking groove is positioned vertically under the lower part of the displacement groove 40.

(22) FIG. 6a shows that the locking system may be formed such that several parts are flexible for example the protrusion 34, the locking strip 6 and the locking element 8. This flexibility may be used to eliminate production tolerances and to facilitate an easy and strong locking. FIG. 6a shows that the strip 6 may be bended downwards and the locking element 8 may be bended downwards and outwardly. Such a strip bending may facilitate locking that may even be accomplished with a displaceable tongue that comprises a limited flexibility such as a tongue that essentially comprises wood fibre material. A locking be accomplished with a flexibility where a part of the displaceable tongue 30 is bended or compressed marginally for example only about 0.1-1.0 mm in the horizontal direction.

(23) FIGS. 6b and 6c show embodiments of the tongue. The displaceable tongue may be fixed into the displaceable groove with a friction connection 38. The protrusion 34 may comprise flexible parts 39 that create a pre-tension against the tongue groove 20. The cavity 35 may be considerably larger than the protrusion and preferably there is a space S that may be about 1-3 mm.

(24) FIG. 6d shows a locking system with a sliding surface 45 that protrudes beyond a vertical plane VP. The tongue groove 20 is preferably formed on an inclined edge surface 46. Such an embodiment offers the advantages that the displaceable tongue 30 may be pressed inwardly and the conventional two-way snapping action may be combined with a one way pressing motion that may be used to create the final locking.

(25) FIG. 6e shows a separate tongue 30, located in a sideway open groove 40 on the second panel 1, comprising an upwardly extending snap tab 47 that cooperates with a downwardly extending sliding surface 45 that is located on the first panel 1 and that protrudes beyond the upper edge and the vertical plane VP. The second panel 1 comprises preferably an inclined edge surface 46 located above and and/or below the tongue 30. An easy snapping may be obtained even with panels that have straight and sharp upper adjacent edges. The snap tab may be replaced with a displaceable tongue that comprises flexible snapping protrusions along its length. The locking system shown in FIG. 1d may also be adjusted such that it comprises inclined edge surfaces and such a design may be used to increase the strength of the joint.

(26) The locking system according to the disclosure may also be formed without a locking grove 14 and a locking element 8 such that it only locks the edges in a vertical direction. The locking element 8 may be replaced with local protrusions that extend upwards from a strip 6 and are in locked position located in the cavities. The short edges may be locked horizontally by friction between the long edges.

(27) All locking systems may be designed such that they be unlocked with angling and/or sliding along the edges.

(28) FIG. 7a, 7b show a tongue blank 43 that comprise several displaceable tongues that are preferably asymmetric along the tongue length. FIG. 7a shows injection-moulded tongues 30 and FIG. 7b shows displaceable tongues 30 made of a wood based material that is preferably machined and punched.

(29) The cavities 35 that are preferably formed by rotating saw blades comprises an upper part that is rounded and may comprise an inner part that is located below an outer part. The locking system may be partly or completely formed by carving tools.

(30) While illustrative embodiments of the invention have been described herein, the present invention is not limited to the various preferred embodiments described herein but includes any and all embodiments having equivalent elements, modifications, omissions, combinations (e.g. of aspects across various embodiments), adaptations and/or alterations as would be appreciated by those in the art based on the present disclosure. The limitations in the claims are to be interpreted broadly based on the language employed in the claims and not limited to the examples described in the present specification or during prosecution of the application, which examples are to be construed as non-exclusive.