Patent Application
20200109569
The disclosure generally relates to the field of mechanical locking systems for floor panels and building panels. The disclosure shows floorboards, furniture components, locking systems and production methods.
Embodiments of the present invention are particularly suitable for use in floating floors, which are formed of floor panels having of one or more upper layers comprising, e.g., thermoplastic or thermosetting material or wood veneer, an intermediate core of wood-fibre-based material or plastic material and preferably a lower balancing layer on the rear side of the core. Embodiments of the invention can also be used for joining building panels which preferably contain a board material for instance wall panels, ceilings, furniture components and similar.
The following description of prior-art technique, problems of known systems and objects and features of the invention will therefore, as a non-restrictive example, be aimed above all at this field of application and in particular at laminate floors comprising an HDF core and formed as rectangular floor panels with long and shorts edges intended to be mechanically joined to each other on both long and short edges.
The long and short edges are mainly used to simplify the description of the invention. The panels may be square. Floor panels are generally produced with the surface layer pointing downwards in order to eliminate thickness tolerances of the core material. Some embodiments and production methods are shown with the surface pointing upwards in order to simplify the description.
It should be emphasized that embodiments of the invention can be used in any floor panel on long and/or short edges and it may be combined with all types of known locking systems on long or short edges that lock the panels in the horizontal and/or vertical direction.
Relevant parts of this background description are also a part of embodiments of the disclosed invention.
Several floor panels on the market are installed in a floating manner with mechanical locking systems formed at the long and short edges. These systems comprise locking means, which lock the panels horizontally and vertically. The mechanical locking systems are usually formed by machining of the core of the panel. Alternatively, parts of the locking system can be formed of a separate material, for instance aluminum or plastic material, which is integrated with the floor panel, i.e. joined with the floor panel in connection with the manufacture thereof.
Laminate flooring usually comprise a 6-8 mm wood based core, a 0.2 mm thick upper decorative surface layer of laminate and a 0.1 mm thick lower balancing layer. The laminate surface and the balancing layer comprise melamine-impregnated paper. The most common core material is fibreboard with high density and good stability usually called HDF—High Density Fibreboard. The impregnated surface and balancing papers are laminated to the core with heat and pressure. HDF material is hard and has a low flexibility especially in the vertical direction perpendicular to the fibre orientation.
Recently a new type of powder based laminate floors has been introduced. Impregnated paper is replaced with a dry powder mix comprising wood fibres, melamine particles, aluminum oxide and pigments. The powder is applied on an HDF core and cured under heat and pressure. Generally high quality HDF is used with a high resin content and low water swelling. Advanced decors may be formed with digital printing. Water based ink is injected into the powder prior to pressing.
Luxury vinyl tile, LVT, flooring with a thickness of 3-6 mm usually comprises a transparent wear layer which may be coated with an ultraviolet, UV, cured polyurethane, PU, lacquer and a decorative plastic foil under the transparent foil. The wear layer and the decorative foil are laminated to one or several core layers comprising a mix of thermoplastic material and mineral fillers. The plastic core may be rather soft and flexible but also rather rigid depending on the filler content.
Wood Plastic Composite floors generally referred to as WPC floors are similar to LVT floors. The core comprises thermosetting material mixed with wood fibre fillers and is generally stronger and much more rigid than the mineral based LVT core.
Thermoplastic material such as PVC, PP or PE may be combined with a mix of wood fibres and mineral particles and this may provide a wide variety of floor panels with different densities and flexibilities.
Moisture resistant HDF with a high resin content, and WPC floors comprise stronger and more flexible core materials than conventional HDF based laminate floors and they are generally produced with a lower thickness.
The above mentioned floor types comprise different core materials with different flexibility, density and strengths. Locking systems formed in one piece with the core must be adapted to such different material properties in order to provide a strong and cost efficient locking function.
In the following text, the visible surface of the installed floor panel is called “front side” or “floor surface”, while the opposite side of the floor panel, facing the sub floor, is called “rear side”. The edge between the front and rear side is called “joint edge”. By “horizontal plane” is meant a plane, which extends parallel to the front side. Immediately juxtaposed upper parts of two adjacent joint edges of two joined floor panels together define a “vertical plane” perpendicular to the horizontal plane. By “vertical locking” is meant locking parallel to the vertical plane. By “horizontal locking” is meant locking parallel to the horizontal plane.
By “up” is meant towards the front side, by “down” towards the rear side, by “inwardly” mainly horizontally towards an inner and centre part of the panel and by “outwardly” mainly horizontally away from the centre part of the panel.
For mechanical joining of long edges as well as short edges in the vertical direction and horizontal direction perpendicular to the edges several methods may be used. One of the most used methods is the angle-snap method. The long edges are installed by angling.
Horizontal snapping locks the short edges. The vertical connection is generally a tongue and a groove and the horizontal connection is a strip with a locking element in one edge that cooperates with a locking groove in the adjacent edge. Locking by snapping is obtained with a flexible strip that during the initial stage of locking bends downwards and during the final stage of locking snaps upwards such that the locking element is inserted into the locking groove.
Similar locking systems may also be produced with a rigid strip and they are connected with an angling-angling method where both short and long edges are angled into a locked position.
Advanced so-called “fold down locking systems” with a separate and flexible tongue on a short edge generally called “5G systems” have been introduced where both the long and short edges are locked with an angling action. A floor panel of this type is presented in WO 2006/043893. It discloses a floor panel with a short edge locking system comprising a locking element cooperating with a locking groove, for horizontal locking, and a flexible bow shaped so called “banana tongue” cooperating with a tongue groove, for locking in a vertical direction. The flexible bow shaped tongue is inserted during production into a displacement groove formed at the edge. The tongue bends horizontally along the edge during connection and makes it possible to install the panels by vertical movement. Long edges are connected with angling and a vertical scissor movement caused by the same angling action connects short edges. The snapping resistance is low and only a low thumb pressure is needed to press the short edges together during the final stage of the angling. Such a locking is generally referred to as “vertical folding”
Similar floor panels are further described in WO 2007/015669. This invention provides a fold down locking system with an improved flexible tongue so called “bristle tongue” comprising a straight outer tongue edge over substantially the whole length of the tongue. An inner part of the tongue comprises bendable protrusions extending horizontally along the tongue body.
The above known fold down “5G system” has been very successful and has captured a major market share of the premium world laminate and wood flooring markets. The locking is strong and reliable mainly due to the flexibility and pretension of the separate flexible tongue that allows a locking with large overlapping essentially horizontal locking surfaces. The locking strength and installation is only to a minor extent dependent on the properties of the core since the strength and flexibility is obtained with a well-defined tongue made of strong plastic material reinforced with long glass fibres.
The 5G system and similar system have been less successful in the low priced market segments. The major reason is that the cost of the separate tongues and investments in special inserting equipment that is needed to insert a flexible tongue into a displacement groove are still regarded as rather high in relation to the rather low price of the floor panels.
Several attempts have been made to provide a fold down locking system based on a vertical snapping function that may be produced in one piece with the core in the same way as the one piece horizontal snap systems. All such attempts have failed especially when a floor panel comprises an HDF core. This is not a coincidence. The failure is based on major problems related to material properties and production methods. Several of the known locking systems are based on theoretical geometries and designs that have not been tested in industrial applications. One of the main reasons behind the failure is that bending of vertically protruding parts that are used for the vertical locking of edges is limited to about 50% of the floor thickness or to about 4 mm in an 8 mm thick laminate floor panel. As comparison it may be mentioned that a protruding strip for horizontal snapping may extend over a substantial distance from the upper edge and may protrude 8-10 mm beyond the upper edge. This may be used to facilitate a downward bending of the strip and the locking element. In addition a small downward bending of the tongue and upward bending of the upper lip are features that are favorable and may be used to facilitate a horizontal snapping action. Other disadvantages compared to horizontal snapping are that HDF comprises a fibre orientation substantially parallel with the floor surface. The material properties are such that bending of horizontally protruding parts is easier to accomplish than bending of vertically protruding parts. Furthermore, lower parts of an HDF board comprise a higher density and a higher resin content than middle parts and such properties are also favorable for the horizontal snapping systems where the strip is formed in the lower part of the core.
Another circumstance that has supported market introduction of the horizontal one piece snap systems is the fact that a hammer and a knocking block may be used to snap the short edges. Fold down systems are so called tool-less systems and the vertical locking must be accomplished with hand pressure only.
Several attempts have been made to copy the basic principles of the 5G tongue that bends horizontally along its length in an displacement groove during locking and that is very stable in the vertical direction where it is supported over the major part of its width by an upper strong and rigid wall of the displacement groove.
The main problem with one-piece systems based on flexible locking means extending along the joint is the fact that it is difficult to combine a high degree of flexibility in the horizontal direction, that is needed for an easy locking, with a low or preferably non-existent flexibility in the vertical direction that is needed for a high locking strength.
WO 2008/116623 describes a locking system comprising a flexible tongue that bends horizontally along its length. The flexible tongue is formed by jumping tools on an outer or inner part of the fold panel. The jumping tools are used to form cavities above and behind the tongue in order to accomplish flexibility in the length direction of the tongue. The main problem is that the tongue is flexible horizontally but also vertically and the vertical locking strength is very low. The jumping tool forms deep cavities and this reduces the locking strength.
WO 2009/033623 describes a locking system having spring elements that lock adjacent panels vertically. The spring elements are located at an outer part of a locking strip and are formed by a vertical slot located in a locking element at an outer part of the locking strip. During vertical displacement the spring elements are displaced horizontally inwardly by projections formed on the adjacent panel and back again to its initial position. The locking element is used to lock vertically, horizontally and to support the panels such that they are aligned with flat upper edges. Such locking system has several disadvantages. The essentially horizontal contact surfaces located on the locking element may increase the risk for squeaking sound when the panels are moving vertically since the outer part of the strip is not strong enough and is generally much more flexible than the inner part. Locking with a flexible part that moves to its original position cannot create a strong locking and cannot eliminate production tolerances. The forming of a slot in the thicker outer part of the strip is a difficult operation since an unnecessary high amount of material must be removed. Two special tooling stations must be used to for the slots on one short edge and the projections on the other opposite short edge.
WO 2011/001326 describes a one piece locking system where the flexible tongue is formed on the strip panel in a middle section of a core. A deep cut is formed vertically as a cavity with a distance that extends over the major part of the core material and this will reduce the strength of the edge section. Only a few tongues may be formed at an edge and the locking strength is low especially in HDF material where the middle parts have a rather low density and flexibility.
WO 2013/032391 describes a one piece locking system comprising a slit formed in the locking strip. The locking system is mainly intended to lock very thin LVT panels. The locking surfaces are located at the lower part of strip. Such locking systems are less suitable for thicker laminate panels since the large slit that is used to accommodate a locking protrusion results in low locking strength especially due to the fact that the flexibility in the vertical direction is generally larger than the flexibility in the horizontal direction.
The locking systems described above are also difficult to form in a cost efficient way with known production methods.
A one-piece fold down locking system designed such that it may be formed with high-speed equipment in a cost efficient way and with a quality and locking function similar to the advanced 5G systems may be a major advantage.
An objective of embodiments of the present invention is to provide an improved and more cost efficient fold down locking system for vertical and horizontal locking of adjacent panels wherein the locking system is produced in one piece with the core.
A first specific objective is to provide a locking system wherein a horizontally extending flexible strip may be used to accomplish the vertical and horizontal locking.
A second specific objective is to provide a locking system with essentially horizontally extending locking surfaces for the vertical locking such that a strong locking force may be obtained in the vertical direction.
A third specific objective is to prevent upward bending of flexible parts that are used to obtain a vertical locking of the edges.
A fourth specific objective is to provide several embodiments of locking systems that may be used to meet the specific material properties of different core materials that are used to produce floor panels and furniture components.
A fifth specific objective is to provide locking systems that may be produced with cost efficient methods in a double-end tenor comprising a lower chain and an upper belt that displace the panel in relation to several tool stations.
The above objects of the invention may be achieved by embodiments of the invention.
According to a first aspect of the invention a set of essentially identical floor panels are provided with a mechanical locking system comprising a strip extending horizontally from a lower part of a first edge of a first panel and a downwardly open locking groove formed in an adjacent second edge of a second panel. The strip comprises an upwardly protruding locking element which is configured to cooperate with the locking groove for locking the first edge and the second edge in a horizontal direction parallel to a main plane of the panels and in a vertical direction perpendicularly to the horizontal direction. The locking element and the locking groove comprise an upper and a lower locking surface, which are configured to lock the panels vertically. The strip comprises slits located along the first edge and is configured such that a slit wall is bended horizontally inwardly towards an inner part of the first panel during locking.
The slits may be located closer to an upper part of the first panel than the locking element. Thereby, the slits may be located between the upper part of the first panel and the locking element in a horizontal direction. In a non-restrictive example, the slits may be provided in a thinnest part of the strip. In another non-restrictive example, the slits may be provided in a portion of the strip inside of the thinnest part of the strip.
By a first object being located closer to the upper edge than a second object is here and in the following meant that a horizontal distance between the first object and the upper edge is smaller than a horizontal distance between the second object and the upper edge. This is valid in all aspects and principles of the disclosure, in particular when the object is a locking element, a locking groove, or a slit.
The second edge may be displaced vertically downwards towards the first edge during locking. This includes the case when the second edge is displaced towards the first edge by means of a scissor-like movement, wherein the second edge is gradually displaced towards the first edge from one side edge of the second edge to the other.
By “during locking” is meant at least during an initial stage of the locking. The bending of the slit wall horizontally inwardly towards an inner part of the first panel may occur during an initial stage of the locking.
The slit wall may be further configured to bend horizontally outwardly away from the inner part. The outward bending may occur after the initial stage of the locking. In particular, the outward bending may occur during a final stage of the locking. The slit wall may be configured to be bended at least partly back to an initial position of the slit wall during a final stage of the locking. The initial position of the slit wall may be a position of the slit wall before bending. In a first example, the slit wall is during the final stage bended partly back to the initial position of the slit wall. In a second example, the slit wall is during the final stage bended completely back to the initial position of the slit wall.
The slit wall may be an outer slit wall of the slit. The slit may further comprise an inner slit wall.
There may be at least one slit located along the first edge. In one example, there is one slit located along the first edge. In another example, there is a plurality of slits located along the first edge. Here and in the following, reference will be made only to “slits”.
The slits may extend entirely through the strip.
Alternatively, some of all of the slits may extend partly through the strip. In this case, the slits may be provided in a front side of the strip, thereby being open upwardly, and/or in a rear side of the strip, thereby being open downwardly.
Each slit may be defined by two sidewalls along the first edge. In a first embodiment, the sidewalls are vertical. This type of slits may be formed by means of cutting, punching or carving. In a second embodiment, the sidewalls are inclined or curved. Thereby, there are transition regions at the side edges of each slit such that a depth of the slit increases from a minimal depth at a centre portion of the slit to a maximal depth at a side edge of the slit. This type of slits may be formed by means of milling.
The inner and/or outer slit walls may be vertical. According to alternative embodiments, the inner and/or outer slit walls are inclined or curved.
According to one embodiment, a height of the slits in a thickness direction of the panel may be between 10% and 40%, more preferably between 20% and 30%, of a maximal thickness of the first panel.
A width of a slit may be constant or vary along the first edge and/or in a vertical direction, i.e. along a thickness direction. By “width of the slit” is here meant a length of the slit in a direction perpendicular to the vertical plane at a given vertical distance from the rear side of the panel and at a given horizontal distance from a side edge of the edge. In a first non-limiting example, the slit may be wider at a centre portion of the slit than at its side edges, close to the sidewalls. In a second non-limiting example, the slit may be tapering in a vertical direction downwards. In a third non-limiting example, the slit may be tapering in a vertical direction upwards. Any of the embodiments of the slit above may be combined.
A cross section of the locking groove or a cross section of the locking element may vary along the first and the second edge.
The locking system may in a locked position and along the edges comprise a first rigid edge section and a second flexible edge section comprising one of the slits. Optionally, the second flexible edge section may comprise at least two of the slits, in particular a plurality of slits.
By rigid or essentially rigid is meant that during locking the locking element is horizontally displaced by a distance that is less than 2%-20%, e.g. 5%, of a maximal width of the locking element. Moreover, by flexible is meant that during locking the locking element is horizontally displaced by a distance that is larger than 2%-20%, e.g. 5%, of a maximal width of the locking element.
The first rigid edge section may be configured such that the locking element is in contact with the locking groove and the second flexible edge section may be configured such that there is a space between an inner surface of the locking element and an outer groove wall of the locking groove. In particular, in the first rigid edge section, an inner surface of the locking element may be in contact with an outer groove wall of the locking groove. The space may be provided between essentially the entire inner surface of the locking element and the outer groove wall of the locking groove in the second flexible edge section. Alternatively, the space may be provided only along a vertical distance that corresponds to the active locking surfaces located at the first edge section and configured to lock the panels horizontally. The locking element may engage with the locking groove in a locked position of the panels.
According to one embodiment, the edges may be locked with vertical pretension between lower and upper support surfaces and between upper and lower locking surfaces. The locking element with its upper locking surface may only partly snap back to its original position, preferably less than about 80% of a first inward displacement, and may in a locked position be displaced upwardly in relation unlocked position due to inclined upper and lower locking surfaces. This may increase the locking strength considerably, even in the case when the locking element in locked position is only pressed inwardly about 0.1-0.2 mm.
According to one embodiment, the upper locking surface is provided in the second flexible edge section. The upper locking surface may be removed in the first rigid edge section. Instead, there may be a vertical wall or an essentially vertical wall.
According to one embodiment, the lower locking surface is provided at least in the second edge section. Alternatively, the lower locking surface may be provided along the entire edge of the second panel.
The edge of the first panel may comprise upper and lower stabilizing surfaces that in locked position overlap each other and prevent an upward bending of the slit wall. By overlap is meant that the stabilizing surfaces form a non-zero overlap at least in a direction perpendicular to the vertical plane and also at least along a portion of the edges. The stabilizing surfaces may engage with each other in the locked position. In particular, the stabilizing surfaces may engage with each other with pretension. Moreover, the lower and/or upper stabilizing surfaces may be provided in the second flexible edge section. According to one embodiment, the upper stabilizing surface is a wall portion of a slit. The wall portion may be an upper wall portion of a slit. According to one embodiment, the lower stabilizing surface is an upper portion of the strip. Optionally, the upper portion of the strip may be arranged in an inner part of the strip.
According to a second aspect of the invention a set of essentially identical floor panels are provided having a mechanical locking system comprising a strip extending horizontally from a lower part of a first edge and a downwardly open locking groove formed in an adjacent second edge. The strip comprises a first and a second upwardly protruding locking element. The first locking element is located closer to the upper edge than the second locking element. The first locking element comprises an upper locking surface at its upper and outer part. The second edge comprises a downwardly extending protrusion comprising a lower locking surface at its outer and lower part. The second locking element cooperates with the locking groove and locks the first and the second edge in a horizontal direction parallel to a main plane of a first and a second panel and the upper and lower locking surfaces lock the adjacent edges in a vertical direction perpendicularly to the horizontal direction. The first and the second edge in comprise in locked position a first edge section and a second edge section along the first and the second edge, wherein a cross section of the first locking element or a cross section of the protrusion varies along the first and/or the second edge. The second edge section comprises a first and a second slit extending side by side along the edge. The first slit is located closer to the upper part of the first edge than the second slit. The second slit is formed between the first and the second locking elements. The locking system is configured to be locked with a vertical displacement of the second edge against the first edge wherein a part of the first locking element and a slit wall of the first and the second slits during an initial stage of the vertical displacement is configured to bend horizontally inwards towards an inner part of the first panel and during a final stage of the vertical displacement is configured to bend outwards towards its initial position.
The upper edge may be an upper edge or upper part of the first edge.
The first edge and the second edge may be an edge of the first panel and an edge of the second panel, respectively.
The first edge may comprise upper and lower stabilizing surfaces that in the locked position overlap each other and prevent an upward bending of one of the slit walls.
Embodiments of the second aspect of the invention are largely analogous to embodiments of the first aspect of the invention, wherein reference is made to the above. In particular, the characteristics of the slits, the upper and lower locking surfaces and the stabilizing surfaces are analogous. In addition, the upper stabilizing surface may be a wall portion of a first slit. The wall portion may be an upper wall portion of a first slit.
There may be one first slit and one second slit. Alternatively, there may be a plurality of first and/or second slits.
According to a third aspect of the invention a set of essentially identical floor panels are provided with a mechanical locking system is provided. The panel edges comprise a strip extending horizontally from a lower part of a first edge and a downwardly open locking groove formed in an adjacent second edge. The strip comprises an upwardly protruding locking element comprising an upper locking surface at its upper and inner part and the locking groove comprises a lower locking surface at its outer and lower part. The locking element cooperates with the locking groove and locks the first and the second edge in a horizontal direction parallel to a main plane of a first and a second panel. The upper and lower locking surfaces lock the adjacent edges in a vertical direction perpendicularly to the horizontal direction. The first and the second edge comprise in locked position a first edge section and a second edge section along the first and the second edge, wherein a cross section of the locking element or a cross section of the locking groove varies along the first and/or the second edge. The strip of the second edge section comprises a slit extending along the first edge. The slit is located between the locking element and an upper edge, wherein the locking system is configured to be locked with a vertical displacement of the second edge against the first edge wherein a part of the locking element and a slit wall during an initial stage of the vertical displacement is configured to bend horizontally outwardly and during a final stage of the vertical displacement is configured to bend inwardly towards its initial position.
The first panel, in particular the first edge, may comprise upper and lower stabilizing surfaces that in locked position overlap each other and prevent an upward bending of a part of the locking element.
Embodiments of the third aspect of the invention are largely analogous to embodiments of the first aspect of the invention, wherein reference is made to the above. In particular, the characteristics of the slits and the stabilizing surfaces are analogous. In addition, the slit may be a first slit and the upper stabilizing surface may be an upper wall of a second slit provided in the strip. The first slit may be provided closer to an upper part of the first edge than the second slit. It is noted, however, that according to the third aspect the direction of the bending is reversed as compared to the first aspect.
Additionally, according to one embodiment, there is a space formed between an inner groove wall of the locking groove and the locking element in a locked position of the panels. The space may allow for a horizontal displacement outwardly of the locking element. The space may extend along essentially the entire edge. Alternatively, however, the space may extend along a part of the edge, preferably at least along the second edge section.
According to one embodiment, the upper locking surface is provided in the second edge section. The upper locking surface may be removed in the first edge section. Instead, there may be a vertical wall.
According to one embodiment, the lower locking surface is provided at least in the second edge section. Alternatively, the lower locking surface may be provided along the entire edge of the second panel.
According to a fourth aspect of the invention a set of essentially identical floor panels are provided with a mechanical locking system comprising a strip extending horizontally from a lower part of a first edge and a downwardly open locking groove formed in an adjacent second edge. The strip comprises an upwardly protruding locking element and the second edge comprises a downwardly extending protrusion comprising a lower locking surface at its lower and outer part. The locking element cooperates with the locking groove and locks the first and the second edge in a horizontal direction parallel to a main plane of a first and a second panel. The first and the second edge in locked position comprise a first edge section and a second edge section along the first and the second edge, wherein a cross section of the protrusion varies along the first and/or the second edge. The second edge section comprises a first and a second slit extending side by side along the edge. The first slit is located closer to the upper part of an edge, in particular the first edge, than the second slit. The second slit is configured to accommodate the protrusion and the lower locking surface such that the lower locking surface locks against an upper locking surface located at a lower and inner part of the second slit and locks the edges in a vertical direction. The locking system is configured to be locked with a vertical displacement of the second edge against the first edge wherein a flexible strip part located between the first and the second slit during an initial stage of the vertical displacement is configured to bend horizontally inwardly and during a final stage of the vertical displacement is configured to bend outwardly towards its initial position.
The edge of the first panel, in particular the first edge, may comprise upper and lower stabilizing surfaces that in locked position overlap each other and prevent an upward bending of the flexible strip part.
There may be one first slit and one second slit. Alternatively, there may be a plurality of first and/or second slits.
Embodiments of the fourth aspect of the invention are largely analogous to embodiments of the first aspect of the invention wherein reference is made to the above. In particular, the characteristics of the slits and the stabilizing surfaces are analogous. In addition, the upper stabilizing surface may be a wall portion of a first slit. The wall portion may be an upper wall portion of a first slit.
Furthermore, the upper locking surface may be located at an outer and lower part of the flexible strip part. The flexible strip part may be configured to bend horizontally inwardly into the first slit.
According to one embodiment, the lower locking surface is provided in the second edge section. The lower locking surface may be removed in the first edge section. Instead, there may be a vertical wall.
According to one embodiment, the upper locking surface is provided at least in the second edge section. Alternatively, the upper locking surface may be provided along the entire edge of the second panel.
According to a fifth aspect of the invention a set of essentially identical floor panels are provided with a mechanical locking system comprising a strip extending horizontally from a lower part of a first edge and a first and a second downwardly open locking groove formed in an adjacent second edge. The first locking groove is located closer to the upper edge than the second locking groove. The strip comprises a first upwardly protruding locking element and a second locking element. The first locking element is located closer to the upper edge than the second locking element. The second edge comprises a downwardly extending protrusion comprising a lower locking surface at its lower and inner part. The first locking element cooperates with the first locking groove and locks the first and the second edge in a horizontal direction parallel to a main plane of a first and a second panel. The first and the second edge comprise in locked position a first edge section and a second edge section along the first and the second edge, wherein a cross section of the protrusion varies along the first and/or the second edge. The second edge section comprises a slit configured to accommodate the protrusion and the lower locking surface such that the lower locking surface locks against an upper locking surface located at a lower and inner part of the second locking element and locks the edges in a vertical direction. The locking system is configured to be locked with a vertical displacement of the second edge against the first edge wherein the second locking element during an initial stage of the vertical displacement is configured to bend horizontally and outwardly and during a final stage of the vertical displacement is configured to bend inwardly towards its initial position.
The first panel, in particular the first edge, may comprise upper and lower stabilizing surfaces that in locked position overlap each other and prevent an upward bending of the second locking element.
Embodiments of the fifth aspect of the invention are largely analogous to embodiments of the first aspect of the invention wherein reference is made to the above. In particular, the characteristics of the slits and the stabilizing surfaces are analogous. In addition, in the second edge section the upper locking surface may be provided in an outer and lower part of the slit. It is noted, however, that in the fifth aspect the direction of the bending is reversed as compared to the first aspect.
According to one embodiment, the slit is a first slit and the second edge section further comprises a second slit, wherein the first and the second slit extend side by side along the first edge, the first slit being located closer to an upper part of the first edge than the second slit. If this embodiment is provided with stabilizing surfaces according to any of the embodiments above, the upper stabilizing surface may be a wall portion of the second slit. The wall portion may be an upper wall portion of the second slit.
There may be one first slit and one second slit. Alternatively, there may be a plurality of first and/or second slits.
According to one embodiment, the lower locking surface is provided in the second edge section. The lower locking surface may be removed in the first edge section. Instead, there may be a vertical wall.
According to one embodiment, the upper locking surface is provided at least in the second edge section. Alternatively, the upper locking surface may be provided along the entire edge of the second panel.
According to a sixth aspect of the invention, there is provided a set of essentially identical furniture components provided with a mechanical locking system for locking a first edge of a first furniture component and a second edge of a second furniture component essentially perpendicularly to each other. The first edge comprises a strip extending from the first edge, wherein the strip comprises a locking element. The second edge comprises a locking groove. The locking element is configured to cooperate with the locking groove for locking the first edge and the second edge in a vertical direction perpendicular to an outer surface of the first furniture component and in a horizontal direction perpendicular to an outer surface of the second furniture component. The locking element and the locking groove comprise an upper and a lower locking surface that are configured to lock the furniture components in the vertical direction. The strip comprises a slit located along the first edge, wherein a slit wall of the slit is configured to be bended horizontally inwardly towards an inner part of the first furniture component during locking. The locking system comprises a first rigid edge section and a second flexible edge section along the first and second edges. The second flexible edge section comprises the slit. In a locked position, the first rigid edge section is configured such that the locking element is in contact with the locking groove and the second flexible edge section is configured such that there is a space between an inner surface of the locking element and a groove wall of the locking groove.
The edge of the first furniture component may comprise upper and lower stabilizing surfaces that in locked position overlap each other and prevent an upward bending of the slit wall.
Embodiments of the sixth aspect of the invention are largely analogous to embodiments of the first aspect of the invention wherein reference is made to the above. In particular, the characteristics of the slits, upper and lower locking surfaces, and the stabilizing surfaces are analogous. It is noted, however, that the sixth aspect is directed to furniture components.
According to a seventh aspect of the invention, there is provided a set of essentially identical floor panels provided with a mechanical locking system comprising a strip formed in one piece with a core of a first panel and extending horizontally from a lower part of a first edge of the first panel. The locking system further comprises a downwardly open locking groove formed in an adjacent second edge of a second panel, the strip comprising an upwardly protruding locking element which is configured to cooperate with the locking groove for locking the first edge and the second edge in a horizontal direction parallel to a main plane of the panels and in a vertical direction perpendicularly to the horizontal direction. The locking element and the locking groove comprise an upper and a lower locking surface that are configured to lock the panels vertically. The strip comprises slits located along the first edge, and a slit wall is configured to be bended horizontally inwardly towards an inner part of the first panel during locking. The core has a higher content of cured resins at a lower and outer part than at a lower and inner part.
The resin may be a thermosetting resin.
The lower and outer part may comprise at least a portion of the strip. Alternatively, or additionally, the lower and outer part may comprise a portion of the second panel located inside of and/or below an outer part of the lower locking surface.
The core may have a higher content of cured resins at an upper and outer part than at an upper and inner part.
The upper and outer part may comprise a portion inside of an upper edge of the first panel. Alternatively, or additionally, the upper and outer part may comprise a portion inside of an upper edge of the second panel.
Embodiments of the seventh aspect of the invention are largely analogous to embodiments of the first aspect of the invention wherein reference is made to the above. In particular, the characteristics of the slits, upper and lower locking surfaces, and the stabilizing surfaces are analogous. Additionally, it is emphasized that the feature of having a higher content of cured resins at lower/upper and outer parts than at lower/upper and inner parts may be combined with locking systems according to any of the other aspects of the invention described above.
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:
The embodiments in
Locking systems comprising flexible and bendable parts formed in one piece with the core are to a major extent dependent of the material properties and thickness of the core that may vary between various core materials and between the same type of core materials. Each locking system must be formed with a specific geometry that is optimized in relation to the properties and thickness of the specific floor panel. This means that a locking system must provide a variety of alternative geometries and principles that could be combined in order to meet the requirements of normal tolerances used in a cost efficient high speed production, locking strength, easy and reliable installation. The inventive concept provides several principles that may be combined and may be used to form a locking system in a specific floor panel.
One solution to this problem would be to form a lot of small flexible tongues along the edge configured such that they are rather easy to bend horizontally inwardly during the vertical folding but hard to bend vertically upwards in locked position. This may be accomplished with several small flexible tongues that are not possible to form with the known production methods and especially not tongues which must be formed by rotating tools that form deep cavities in a core material and that are only open in one direction vertically or horizontally. One solution is to form the small tongues with a thickness T that is larger than the width W and this provides a horizontal flexibility that exceeds the vertical flexibility. Removal of material that may be accomplished by forming an open slit 20 or just by removing material from an edge provides major advantages related to forming of an appropriate joint geometry.
Another solution to this problem would be to form a locking system comprising a stabilizing edge section 17 as shown in
The locking system according to embodiments of the invention is three dimensional and comprises preferably a first rigid edge section 7a having a vertically protruding locking element 8 for horizontal locking and a second flexible edge section 7b comprising a flexible slit 20 that may be bended inwardly such that a distance between the outer 20a and inner 20b slit walls decreases during bending and/or outwardly such that the distance between the slit walls 20a, 20b increases during bending. The distance may be a minimal distance between the outer 20a and inner 20b slit walls. The first rigid edge section 7a and the second flexible edge section 7b are provided along the edges of the first 1 and second 1′ panels. In
The edges are in a second step adjusted and a part of the material at the edges is removed as shown in
The locking element comprises an inner surface 8a, an outer surface 8b and an upper surface 8c. The inner surface 8a is closer to the upper edge 25 of the first panel 1 than the outer surface 8b. By upper edge 25 of the first panel 1 is meant an upper part of the first edge of the first floor panel 1. The locking groove 14 comprises an outer groove wall 14a, an inner groove wall 14b and an upper groove wall 14c. The outer groove 14a wall is closer to the upper edge 25′ of the second panel 1′ than the inner groove wall 14b. By upper edge 25′ of the second panel 1′ is meant an upper part of the second edge of the second floor panel 1′. The locking element 8 comprises an upper locking surface 11a formed in the outer surface 8b of the locking element 8 that in a locked position of the panels 1, 1′ cooperates with a lower locking surface 11b formed in the inner groove wall 14b and that locks the adjacent edges in a vertical direction. According to the present embodiment, the upper 11a and lower 11b locking surfaces are inclined against a horizontal plane. In non-limiting examples, the inclination angle may be between 0° and 45°, more preferably between 5° and 25°, e.g. 20°. The locking element 8 comprises a first locking surface 12a formed in the inner surface 8a of the locking element 8 that in a locked position cooperates with a second locking surface 12b formed in the outer groove wall 14a and that locks the adjacent edges in a horizontal direction. According to the present embodiment, the first 12a and second 12b locking surfaces are essentially vertical walls. The second edge comprises a projection 26 that is adapted to engage with an indentation 28 in the first edge in a locked position. The edges comprise lower and upper support surfaces 15, 16 that in a locked position cooperate with the upper and lower locking surfaces 11a, 11b and prevent the edges to be displaced vertically downwards and vertically upwards. According to the present embodiment, the lower support surface 15 is provided in the first panel 1 between the upper edge 25 and an inner surface 28a of the indentation 28, and the upper support surface 16 is provided in the second panel 1′ between the upper edge 25′ and an outer surface 26a of the projection 26. Moreover, the lower support surface 15 is provided adjacent to the upper edge 25 and the upper support surface 16 is provided adjacent to the upper edge 25′. According to the present embodiment, the lower and upper support surfaces 15, 16 are horizontal but it is understood that inclined lower and upper support surfaces are equally conceivable.
Adjacent edges comprise in locked position a first essentially rigid edge section 7a and a second flexible edge section 7b as shown in
It is understood that according to alternative embodiments the geometries according to
The first edge section 7a is preferably a start section that becomes active during a first initial step of the folding action and the second edge section 7b is preferably a section that becomes active during a second step of the folding action.
In
The panel edges may also comprise a second horizontally extending tongue 50 and a tongue groove 51 formed in the upper part of the panels as shown in
A slit 20 that may be formed from above and/or from below provides the advantages that relationships between vertical and horizontal locking surfaces and the flexibility of the flexible edge section may be adjusted in an easy way and adapted to the properties of the core material.
As shown in
Stabilizing surfaces allow that the length of the slit may be increased and in some applications only one or two slits may be sufficient.
There is provided a first rigid edge section 7a and a second flexible edge section 7b along the edges of the first 1 and second 1′ panels. The first 7a and second 7b edge sections may be arranged according to any of the embodiments described in the above.
Preferably, a preformed groove 30 is formed adjacent to the vertical plane VP that intersects the upper edge 25 of the first panel edge 1.
1. A set of essentially identical floor panels (1, 1′) provided with a mechanical locking system comprising a strip (6) extending horizontally from a lower part of a first edge of a first panel (1) and a downwardly open locking groove (14) formed in an adjacent second edge of a second panel (1′), the strip (6) comprising an upwardly protruding locking element (8) which is configured to cooperate with the locking groove (14) for locking the first edge and the second edge in a horizontal direction parallel to a main plane of the panels and in a vertical direction perpendicularly to the horizontal direction, wherein the locking element (8) and the locking groove (14) comprise an upper (11a) and a lower (11b) locking surface which are configured to lock the panels vertically, wherein
2. The set as in embodiment 1, wherein a cross section of the locking groove (14) or a cross section of the locking element (8) varies along the first and the second edge.
3. The set as in embodiment 1 or 2, wherein the slit wall (20a) is further configured to be bended at least partly back to an initial position of the slit wall (20a) during a final stage of the locking.
4. The set as in any one of the preceding embodiments 1-3, wherein the edge of the first panel (1) comprises upper (18) and lower (19) stabilizing surfaces that in the locked position overlap each other and prevent an upward bending of the slit wall (20a).
5. The set as in any of the preceding embodiments, wherein the first edge and the second edge are locked with vertical pretension between upper (16) and lower (15) support surfaces and between the upper (11a) and lower (11b) locking surfaces.
6. A set of essentially identical floor panels (1, 1′) provided with a mechanical locking system comprising a strip (6) extending horizontally from a lower part of a first edge and a downwardly open locking groove (14) formed in an adjacent second edge, wherein the strip (6) comprises a first (8) and a second (8′) upwardly protruding locking element, the first locking element (8) being located closer to an upper edge (25) of the first edge than the second locking element (8′), wherein the first locking element (8) comprises an upper locking surface (11a) at its upper and outer part, wherein the second edge comprises a downwardly extending protrusion (36a) comprising a lower locking surface (11b) at its outer and lower part, the second locking element (8′) being configured to cooperate with the locking groove (14) and to lock the first and the second edge in a horizontal direction parallel to a main plane of a first and a second panel (1, 1′) and the upper and lower locking surfaces (11a, 11b) being configured to lock the adjacent edges in a vertical direction perpendicularly to the horizontal direction, wherein
7. The set as in embodiment 6, wherein the first edge comprises upper (18) and lower (19) stabilizing surfaces that in the locked position overlap each other and prevent an upward bending of one of the slit walls.
8. A set of essentially identical floor panels (1, 1′) provided with a mechanical locking system comprising a strip (6) extending horizontally from a lower part of a first edge and a downwardly open locking groove (14) formed in an adjacent second edge, wherein the strip (6) comprises an upwardly protruding locking element (8) comprising an upper locking surface (11a) at its upper and inner part and the locking groove (14) comprises a lower locking surface (11b) at its outer and lower part, the locking element (8) being configured to cooperate with the locking groove (14) and to lock the first and the second edge in a horizontal direction parallel to a main plane of a first and a second panel (1, 1′), the upper and lower locking surfaces (11a, 11b) being configured to lock the adjacent edges in a vertical direction perpendicularly to the horizontal direction, wherein
9. The set as in embodiment 8, wherein the first edge comprises upper (18) and lower (19) stabilizing surfaces that in the locked position overlap each other and prevent an upward bending of a part of the locking element (8).
10. A set of essentially identical floor panels (1, 1′) provided with a mechanical locking system comprising a strip (6) extending horizontally from a lower part of a first edge and a downwardly open locking groove (14) formed in an adjacent second edge, wherein the strip (6) comprises an upwardly protruding locking element (8) and the second edge comprises a downwardly extending protrusion (36a) comprising a lower locking surface (11b) at its lower and outer part (32), the locking element (8) being configured to cooperate with the locking groove (14) and to lock the first and the second edge in a horizontal direction parallel to a main plane of a first and a second panel (1, 1′), wherein
11. The set as in embodiment 10 wherein the first edge comprises upper (18) and lower (19) stabilizing surfaces that in locked position overlap each other and prevent an upward bending of the flexible strip part (31).
12. A set of essentially identical floor panels (1, 1′) provided with a mechanical locking system comprising a strip (6) extending horizontally from a lower part of a first edge and a first (14) and a second (14′) downwardly open locking grooves formed in an adjacent second edge, wherein the first locking groove (14) is located closer to an upper edge (25) of the first edge than the second locking groove (14′), wherein the strip (6) comprises a first upwardly protruding locking element (8) and a second locking element (8′), the first locking element (8) being located closer to the upper edge (25) than the second locking element (8′), wherein the second edge comprises a downwardly extending protrusion (36a) comprising a lower locking surface (11b) at its lower and inner part (33), the first locking element (8) being configured to cooperate with the first locking groove (14) and to lock the first and the second edge in a horizontal direction parallel to a main plane of a first and a second panel (1, 1′), wherein
13. The set as in embodiment 12, wherein the first edge comprises upper (18) and lower (19) stabilizing surfaces that in locked position overlap each other and prevent an upward bending of the second locking element (8′).
14. A set of essentially identical floor panels (1, 1′) provided with a mechanical locking system comprising a strip (6) formed in one piece with a core (5) of a first panel (1) and extending horizontally from a lower part of a first edge of the first panel (1) and a downwardly open locking groove (14) formed in an adjacent second edge of a second panel (1′), the strip (6) comprising an upwardly protruding locking element (8) which is configured to cooperate with the locking groove (14) for locking the first edge and the second edge in a horizontal direction parallel to a main plane of the panels and in a vertical direction perpendicularly to the horizontal direction, wherein the locking element (8) and the locking groove (14) comprise an upper (11a) and a lower (11b) locking surface which are configured to lock the panels vertically, wherein
15. The set as in embodiment 14, wherein the resin is a thermosetting resin.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1550033-3 | Jan 2015 | SE | national |
The present application is a continuation of U.S. application Ser. No. 15/841,909, filed on Jul. 6, 2017, which is a U.S. national stage of International Application No. PCT/SE2016/050019, filed on Jan. 15, 2016, which claims the benefit of Swedish Application No. 1550033-3, filed on Jan. 16, 2015. The entire contents of each of U.S. application Ser. No. 15/841,909, International Application No. PCT/SE2016/050019, and Swedish Application No. 1550033-3 are hereby incorporated herein by reference in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15541909 | Jul 2017 | US |
| Child | 16708719 | US |
