Mechanical locking system for floor panels

Abstract

Floor panels provided with a mechanical locking system comprising a separate material in order to reduce snapping resistance during vertical displacement. For example, a separate flexible tongue, the flexible tongue including an inner part, which is connected to a holding groove at a second edge, and an outer flexible snap tab that extends upwardly and in the connected state into a cavity under a protruding tongue for locking a first and a second floor panel to each other in a vertical direction.

Claims

1. A set of floor panels comprising a first floor panel and a second floor panel which are mechanically connectable to each other at a first edge of the first floor panel and a second edge of the second floor panel, wherein a protruding tongue is provided in the first edge, said protruding tongue being formed in one piece with the first floor panel and extending outside of an upper part of said first edge, a separate flexible tongue is arranged in a holding groove provided in the second edge, and the first edge comprises a strip with a locking element and the second edge comprises a locking groove, the locking element being provided horizontally outside said protruding tongue, wherein the first and the second floor panel are mechanically connectable by a vertical displacement towards each other to obtain a connected state in which: a flexible snap tab of the separate flexible tongue cooperates with the protruding tongue for locking the first floor panel and the second floor panel to each other in a vertical direction, the locking element cooperates with the locking groove for locking the first floor panel and the second floor panel to each other in a horizontal direction, wherein the flexible snap tab and the protruding tongue are configured to cooperate during said vertical displacement such that in a first stage at least a part of the flexible snap tab is displaced towards the second edge by the protruding tongue, and in a second stage at least a part of the flexible snap tab is displaced towards the first edge to obtain the connected state.

2. The set of floor panels according to claim 1, wherein the protruding tongue is formed in one piece with a core of the first floor panel.

3. The set of floor panels according to claim 1, wherein the flexible snap tab extends upwardly when the separate flexible tongue is arranged in the holding groove.

4. The set of floor panels according to claim 1, wherein the flexible snap tab is an outer part of the separate flexible tongue.

5. The set of floor panels according to claim 1, wherein the flexible snap tab cooperates with the protruding tongue from below for locking the first floor panel and the second floor panel vertically.

6. The set of floor panels according to claim 1, wherein the locking groove is open towards a rear side of the second floor panel that faces a subfloor.

7. The set of floor panels according to claim 1, wherein said at least a part of the flexible snap tab is resiliently displaced towards the second edge by the protruding tongue in the first stage.

8. The set of floor panels according to claim 1, wherein said at least a part of the flexible snap tab is in a position displaced towards the second edge by the protruding tongue in the first stage, and said at least a part of the flexible snap tab is in a position displaced towards the first edge in the second stage to obtain the connected state.

9. The set of floor panels according to claim 1, wherein an outer part of the protruding tongue comprises an inclined or rounded guiding surface at an upper and outer part of the protruding tongue.

10. The set of floor panels according to claim 1, wherein the protruding tongue is arranged above the strip.

11. The set of floor panels according to claim 1, wherein the protruding tongue is arranged at a vertical plane and extends outside of said vertical plane, wherein the vertical plane is provided between or intersects an upper edge of said first edge and an upper edge of said second edge in the connected state.

12. The set of floor panels according to claim 1, wherein a space is provided between an upper part of the protruding tongue and the second edge in the connected state.

13. The set of floor panels according to claim 1, wherein a space is provided between an upper part of the strip and the second edge in the connected state.

14. The set of floor panels according to claim 1, wherein the protruding tongue comprises, at a lower part of the protruding tongue, a locking surface which in the connected state is configured to cooperate with the flexible snap tab.

15. The set of floor panels according to claim 14, wherein the locking surface of the lower part of the protruding tongue is inclined.

16. The set of floor panels according to claim 14, wherein the locking surface of the lower part of the protruding tongue is arranged above the strip.

17. The set of floor panels according to claim 1, wherein the protruding tongue and the flexible snap tab are configured such that an initial contact, during said vertical displacement, between the protruding tongue and the flexible snap tab is obtained at an upper part of the flexible snap tab.

18. The set of floor panels according to claim 1, wherein the separate flexible tongue is glued into the holding groove.

19. The set of floor panels according to claim 1, wherein the separate flexible tongue has an inner part connected to holding groove.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will by way of example be described in more detail with reference to the appended schematic drawings, which shows embodiments of the present invention.

(2) FIGS. 1-5b illustrate known systems.

(3) FIGS. 6a-6c illustrate a first embodiment of the invention.

(4) FIGS. 7a-7b illustrate a second embodiment of the invention.

(5) FIGS. 8a-8b illustrate a third embodiment of the invention.

DETAILED DESCRIPTION

(6) 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.

(7) A known “fold down” installation method is described in FIGS. 1-4. Locking of short edges 1b, 1c takes place with a scissors like movement where a flexible tongue 30 is displaced inwardly gradually from one edge to the other edge when a long side of a panel 1c in one row is connected by angling to an adjacent panel 1a in a previously installed row. A flexible snap tab 33, which in most cases is made of a plastic section, is during folding bended horizontally along the joint. A part of the snap tab is during folding pressed inwardly, as shown in FIG. 1, and other parts are in contact with the adjacent edge, FIG. 2, or in an completely unlocked position, as shown in FIG. 4. The horizontal locking takes place when a locking element 8 located on a strip 6 on a first panel 1b, hereafter referred to as strip panel, cooperates with an adjacent second panel 1c, hereafter referred to as fold panel, such that the locking element 8 is inserted into a locking groove 14.

(8) FIGS. 5a and 5b show that the flexible tongue 30 may be connected to an edge of the fold panel 1c or the strip panel strip panel 1b.

(9) From a production perspective it is an advantage if the flexible tongue 30 is connected to a fold panel 1c because it is easy to insert such a flexible tongue into a holding groove 32. There is no protruding strip 6 and the insertion of the flexible tonged may be made with an inserting equipment comprising rather simple guiding devices that guide the tongue into the holding groove 32. A problem with such a flexible tongue 30, as shown in FIG. 5a, is that the locking system is difficult to lock since the snap tab must be pressed inwardly by a sharp upper edge.

(10) FIGS. 6a-6c show an embodiment of the invention. A strip panel 1b comprising a strip 6 and a locking element 8 which cooperates with a locking groove 14 in a fold panel 1c for horizontal locking of two adjacent edges of the fold panel 1c and the strip panel 1b is provided. The strip panel comprises a protruding tongue 10 with an upper inclined or rounded guiding surface 11 and a lower locking surface 12. The fold panel 1c comprises a flexible tongue 30 in a holding groove 32, which is open towards the vertical plane VP. The flexible tongue 30 has an inner part 34 connected into the holding groove 32 and a flexible snap tab 33 with a sliding surface 35 extending outwardly and upwardly. The sliding surface 35, that preferably is located at an upper part of the flexible snap tab, cooperates with the guiding surface 11 during a vertical displacement of the fold panel 6c and causes a pressure force that bends the flexible snap tab 33 inwardly towards the holding groove 32 as shown in FIGS. 6a-6b. The snap tab 33 snaps back toward its initial position and into the cavity 31 when the edges 1b, 1c are aligned horizontally and the lower locking surface 12 on the lower part of the protruding tongue 10 locks against the upper part of the snap tab 33 as shown in FIG. 6c. The flexible snap tab 33 and the protruding tongue 10 lock the edges vertically parallel to the vertical plane VP. The locking element 8 and the locking groove 14 lock the edges in a horizontal direction perpendicular to the vertical plane VP. The strip 6 and the protruding tongue 10 form a cavity 31 that in connected state accommodates an outer part of the flexible snap tab 33. The protruding tongue is preferably arranged above the strip, at the vertical plane and extends from the vertical plane. The locking surface of the protruding tongue is preferably arranged above the strip.

(11) The inclined guiding surface 11 facilitates an easy locking since the flexible snap may not be in contact during locking with the upper sharp edge of the panel surface. The guiding surface may be used to facilitate an easy locking even in the case that a contact may exist during folding between the upper edge and the flexible snap tab 11.

(12) The lower locking surface 12 may be inclined and the locking may be made with a pre tension such that the snap tab 11 in locked position is pressed against a lower part of the protruding tongue 10.

(13) FIG. 7a shows that there may be a space S1 between the upper part of the tongue 10 and the adjacent panel edge. The vertical locking is accomplished with an upper contact point A between the protruding tongue 10 and the flexible snap tab 33, and a lower contact point B between the strip 6 and a lower edge of the fold panel 1c. The snap tab may be flexible or rigid depending on the design and material composition. Polymer materials are preferred and the flexible tongue may comprise several different materials in for example the inner part or in the snap tab. The flexible tongue 30 may comprise a knee joint 36 with increased flexibility that facilitates bending and/or displacement of the snap tab. The locking groove 14 and the holding groove 32 are preferably horizontally displaced, in order to obtain a strong locking system, and preferably with a distance D1 that is at least about 30% of the floor thickness T. The upper part of the locking groove 14 and the inner part of the holding groove 32 are preferably also displaced vertically with a distance D2.

(14) FIG. 7b shows that there may be a space S2 between the upper part of the strip 6 and the lower edge of the adjacent fold panel 1c. The vertical locking is in this embodiment accomplished with a lower contact point B between the protruding tongue 10 and the flexible snap tab 33, and an upper contact point A between the protruding tongue 10 and an upper part of the fold panel 1c that overlaps the protruding tongue.

(15) FIG. 8a shows an embodiment where the upper edges of the panels are in contact with each other and the guiding surface 11 extends downwardly from the panel surface. The knee joint 36 comprises a flexible material 37 that is softer than the inner part 34 and the snap tab 33. The flexible tongue 30 comprises an inner part 34 that comprises a lower part 34a located under the flexible snap tab 33.

(16) FIG. 8b shows an embodiment where the holding groove 32 comprises glue 38 and the flexible tongue 30 is glued into the holding groove. This gives a stronger locking system and cracks C extending primarily between the holding groove 32 and the locking groove 14 may be avoided. The lowest part of the flexible tongue 30 may be located essentially on the same horizontal plane as the lower and outer part 39 of the fold panel 1c. The holding groove may comprise an upper wall and a lower wall and an inner wall extending between the upper and the lower wall. The glue is preferably provided at the upper, the lower and the inner wall. The flexible tongue is preferably glued to the upper, the lower and the inner wall.