SK287962B6 - Flooring system and floorboard for installation thereof - Google Patents

Abstract

A flooring system comprises floorboards (1, 11) mechanical jointed at a joint plane (VP), said floorboards (1, 11) having a core (30), a front side (2, 32), a rear side (34) and opposite joint edge portions (4a, 4b), of which one (4a) is formed as a tongue groove (36) which is defined by upper and lower lips (39, 40). A bottom end (48) and the other (4b) is formed as a tongue (38) with an upwardly directed portion (8). The tongue groove (36), seen from the joint plane (VP), has the shape of an undercut groove. At least the major part of the bottom end (48) of the tongue groove (36), seen parallel with the surface plane (HP), is positioned further away from the joint plane (VP) than is the outer end (69) of the tongue (38). The inner locking surface (45) of the tongue groove (36) is formed on the upper lip (39) within the undercut portion (35) of the tongue groove for coaction with the corresponding locking surface (65) of the tongue (38), which locking surface is formed on the upwardly directed portion (8) of the tongue (38). The lower lip (40) has a supporting surface (50) for coaction with a corresponding supporting surface (71) on the tongue (38).

Description

The present invention relates to a flooring system comprising floorboards mechanically connected in the plane of the joint as well as floorboards for making this system. In particular, the invention is intended for wood-based floorboards which normally have a wood core and are intended for mechanical joining.

BACKGROUND OF THE INVENTION

In the short time, mechanical joining has achieved wide application especially due to its excellent laying properties, strength and joining quality. Even floors according to WO 9426999, as detailed below, and floors sold under the Alloc® brand have greater advantages compared to traditional glued floors, but further improvements are desirable.

Mechanical bonding systems are very advantageous for bonding not only laminate floors, but also wood and composite floors. These floorboards can be composed of a variety of different surface, core and back materials. As will be described below, these materials can be contained in various parts of the fastening system, such as the tape, the locking member and the tongue. A solution comprising a connecting tape that is shaped e.g. according to WO 9426999 or WO 9747834 and which provides a horizontal joint, and further comprising a tongue that provides a vertical joint, however, results in costs in the form of waste material that is generated when machining the board material.

For optimal function eg. 15 mm thick parquet flooring should have a tape width approximately equal to the floor thickness, ie. j. about 15 mm. With a tongue of approximately 3 mm, the waste will be 18 mm. The floorboard has a normal width of approximately 200 mm. The waste material will therefore be 9%. Generally, the cost of waste material will be large when the floorboards are made of expensive material, if they are thick or their size is small, so the number of common meters of joints per square meter of flooring is large.

Undoubtedly, the amount of waste is reduced if the tape used is in the form of a separately manufactured aluminum tape which is already attached to the floorboards in production. In addition, aluminum tape can have many uses that will be a more convenient and cheaper bonding system than tape, machined and molded from the core. Aluminum, however, is disadvantageous if it is necessary to reconstruct in production and the large investment costs of reconstructing an existing traditional production line where a mechanical fastening system is produced. The advantage of the current aluminum tape is that the initial format of the floorboards need not be changed.

If the tape produced by machining the floorboard material is damaged, it may be reversed. Therefore, the format of the floorboards must be adapted so that there is sufficient material for shaping the tape and tongue. For laminate floors it is often necessary to change the width of the decorative paper used. All these modifications and changes also require costly adaptation of the production equipment and a large adaptation of production.

In addition to the aforementioned problems relating to unwanted material waste, production costs and production adaptation, the tape has the disadvantage of being susceptible to damage during transportation and installation.

In summary, it is necessary to ensure a mechanical connection at a low production cost, while at the same time endeavoring to maintain the present excellent properties regarding the placement, lifting, quality and strength of the joint. With an existing solution, it is not possible to achieve low cost without simultaneously reducing standard strength and / or placement. SUMMARY OF THE INVENTION It is an object of the present invention to provide a solution for reducing costs while maintaining strength and function.

The invention is based on known floorboards having a core, a front side, a rear side and opposed connecting edges, one of which is shaped as a joint groove defined by an upper and a lower edge and which has a lower end, and the other connecting edge is a tongue with upwards part at its free outer end. The coupling groove has the form of a tooth groove with an opening, an inner part and an inner locking surface. At least portions of the lower edge are formed together with the floorboard core and the tongue has a locking surface which is designed to cooperate with the inner locking surface in the groove of the adjacent floorboard, whereby two such floorboards are mechanically joined so that their front sides are in the same surface plane - HP - and meet in a joint plane -VP- that is exactly perpendicular to it. This technique has been disclosed in DE-A-3041781 and will be further discussed below.

However, the general technique for floorboards will be described above. Locking systems for mechanical locking of floorboards will be described as the basis of the present invention.

In order to facilitate understanding of the present invention as well as the problems prior to the invention, both the basic structures and functions of the floorboards of WO 9426999 and WO 9966151 are described with reference to Figures 1-17 in the accompanying drawings. An embodiment of the present invention, if described, has also been used in suitable portions of the description of the prior art.

Figures 3a and 3b show the floorboard J according to WO 9426999 from above and below. The plate J is rectangular with an upper side 2, a lower side 3, two opposing long sides with connecting edges 4a, 4b, and two opposite short sides with connecting edges 5a and 5b.

The long side joint edges 4a, 4b as well as the short side joint edges 5a, 5b can be mechanically bonded without adhesive in the direction D2 in FIG. 1c such that they meet on the joining plane VP shown in Figure 2c, in the assembled state, the common tops must be on the common surface plane HP shown in Figure 2c.

In the illustrated embodiment, which is an example of floorboards according to WO 9426999, in Figures 1 to 3 in the accompanying drawings, the board 1 has a factory-fitted flat strip 6 which extends along the entire long side 4a and is made of resilient, tough aluminum sheet. . The strip 6 extends outward beyond the joint plane VP at the joint edge 4a. The tape 6 may be attached mechanically according to the illustrated embodiment or by means of an adhesive, or in some other way. As mentioned in the documents, other tape materials such as sheet metal of other material, aluminum or plastic profiles can also be used for the factory-attached tape. As also stated in WO 9426999 and described and illustrated in WO 9966151, the tape 6 can be shaped simultaneously with the plate J, e.g. suitably machining the core of the board L

Said solution is applicable to floorboards, wherein the tape or at least a portion thereof is shaped together with the core, the invention solves special problems that arise with these floorboards and the article thereof. The floorboard core need not be made of a homogeneous material, but it is preferable. The tape 6 is integral with the plate 1, i. j. it should be molded on a plate or mounted at the factory.

In the known embodiments of WO 9426999 and WO 9966151, the width of the tape 6 can be about 30 mm and the thickness about 0.5 mm.

Similarly, if the shorter tape & is inserted along the short side 5a of the plate L The portion of the tape 6 beyond the joint plane VP is formed with a locking element 8 that is along the entire tape 6. The locking element 8 has a working lock in its shorter part a surface 10 lining the joint plane VP of height e.g. 0.5 mm. In the laid state, this locking surface 10 is in contact with the locking groove 14, which is formed on the underside 3 of the connecting edge 4b of the opposite long side of the adjacent plate U. The tape & along the short side has a corresponding locking element f1 and the connecting edge 5b of the opposite short side a corresponding cam groove 14 '. The edge of the cam groove 14, 14 'facing away from the joint plane VP forms a working cam surface 10' for cooperation with the working cam surface 10 of the cam element.

For mechanical connection of both long and short sides also in the vertical direction, i. j. direction D1 in FIG. 1c, also the plate 1 along one long side - the connecting edge 4a - and one short side - the connecting edge 5a - is formed on the side by an open recess or tongue groove 16. This is determined by the upper projection on the connecting edge 4a, 5a and bottom by strips 6. and &. At the opposite edge 4b, 5b there is an upper recess 18 which defines a tongue 20 which cooperates with the recess or tongue groove 16 - see FIG. 2a.

Figures 1a to 1c illustrate how the two long sides 4a and 4b of two such plates 1, U on base U can be connected obliquely downward by pivoting about a center C that is just in cross section between the plane of the HP surface and the joint plane VP while holding the plates in contact with each other.

Figures 2a to 2c show how the short sides 5a, 5b of the plates J, U can be clamped together. The long sides 4a, 4b can be connected in both ways, the joining of the short sides 5a, 5b after laying the first row of floorboards is normally done only by pinching after the long sides 4a, 4b have first been joined.

If the new plate V and the previously laid plate I are joined by the edges 4a and 4b of their long sides according to Figures 1a-1c, the edge 4b of the new plate U is pressed against the long edge edge 4a of the previously laid plate J according to Fig. 1a. The plate U is then folded down against the substrate U of Figure 1b. The locking tongue 20 fills the recess or the locking groove 16 and at the same time the locking element 8 of the tape 6 fits into the locking groove 14. During this downward movement the upper part 9 of the locking element 8 can act and apply the new plate U to the previously laid plate L

In this coupled position of Figure 1c, the plates 1a T are locked in the direction D1 as well as in the direction D2 along the joint edges 4a and 4b of their long sides, but the plates 1af can slide against each other in the longitudinal direction joined along the long side t. j. in direction D3.

Figures 2a - 2c show how the edges 5a and 5b of the short sides of the boards 1 and 1 'can be mechanically joined in the direction D1 as well as D2 by moving the new board 1' horizontally towards the previously laid board 1. This can be done after The long side of the new board U is applied, in particular by tilting the new board U inwardly according to FIGS. 1a to 1c, and connected to the previously laid board 1 in a row. In the first step in Figure 2a, the beveled areas of the recess 16 and the lock tongue cooperate so that the tape 16 is pressed down as a direct result of the approaching edges of the short sides 5a, 5b. At the end of the approach, the tape 6 engages when the lock element enters the lock groove 14 '. so that the working cam surfaces W, 10 'on the cam element 8 / cam groove 14' engage.

By repeating the operations shown in Figures 1a-c and 2a-c, the entire floor can be laid without glue along all the connecting edges. Thus, existing floorboards of this type may be mechanically joined, as a rule, they fold down long side or short side, when the long side is locked, are clamped together by horizontal displacement of the new board D along the long side of the previously laid board i - in D3 direction. . The plates 1, V can be disassembled without damaging the joint in the reverse order of laying and repositioning. Parts of these laying principles are also applicable in connection with the present invention.

In order to optimize the function and to facilitate laying and disassembling, the present plates should, after joining along their long sides, assume a position where there is minimal freedom of movement between the locking element working surface 10 and the locking groove working surface 10 'but between the planar plates. the joint VP closed by the top of the plates, i.e. j. in the plane of the HP surface, no play is permitted. For such a position, one plate must be pushed against the other, if necessary. A more detailed description can be found in WO 9426999. This clearance can be in the range of 0.01-0.05 mm between the working locking surfaces 10, 10 'when the long sides of adjacent plates are pressed against each other. This free movement facilitates the entry of the locking element 8 into the locking groove 14, 14 'and vice versa. As noted, no play is desirable in the joint between the slabs, in the section plane of the HP plane, and in the plane of the joint VP on the floorboard surface.

The joining system allows displacement along the joining edge in the locked position after attaching any side. Laying can therefore take place in different ways, but they are all based on three basic principles:

• Lowering the long side and lowering the short side.

• Long Side Lock - Short Side Lock.

• Tilt the short side, tilt the two boards up, move the new board along the edge of the short side of the original board, and finally tilt both boards down.

The most common and safest way of laying is when the long side is first folded down and locked with another floorboard. Subsequently, the displacement is performed in the locked position against the short side of the third floorboard, and the short side is clamped. The laying can also be carried out with one side, long or short, which is clamped together with the other plate. They are then moved in the locked position until the next side is pinched with the third plate. These two methods require fitting on at least one side. But laying can also be done without gripping. A third alternative is that the short side of the first plate is tilted first inside the short side of the second plate, which is already connected by the long side with the third plate. After this connection, the first and second plates are slightly tilted upwards. The first plate is moved to a position tilted up along the short side until the upper joining edges of the first and third plates are in contact with each other, after which the two plates are folded down together.

The floorboards described and their locking system have also been very successful on the market in connection with laminate floors having a thickness of approximately 7 mm and an aluminum strip 6 with a thickness of 0.6 mm. Similar commercial variants of the floorboards according to WO 9966156 shown in Figures 4a and 4b are successful. However, it has been found that this technique is not particularly suitable for fiber-based materials, in particular for solid wood materials or glued laminate wood materials for parquet floors. One of the reasons why this technique is not suitable for this type of product is the large amount of waste material that increases as a result of machining portions of the edges to form a tongue groove with the necessary depth.

To partially eliminate this problem, it would be possible to use the technique shown in Figures 5a and 5b in the accompanying drawings and described and illustrated in DE-A-3343601, i. j. that it would be possible to shape the two connecting edges of the individual elements which are attached to the edges of the long sides. This technique also has a high cost of aluminum parts and the considerable machining that is necessary. Moreover, it is difficult to attach the modular elements along the edge in an economical manner. The geometry shown does not allow assembly and disassembly without significant downward and upward free movement, as the components will not fit freely into each other during these movements if they are made for precision fit - see Figure 5b.

Another known floorboard design with a mechanical locking system is shown in Figures 6a-d in the accompanying drawings and described and shown in CA-A-0991373. When this mechanical locking system is used, all forces that try to pull the long sides of the plates apart lift the locking element at the outer end of the tape - see Figure 6a. If the floor is laid and closed, the material shall be resilient to allow the tongue to rotate about two centers simultaneously. The tight fit between all surfaces does not allow rational production and relocation in the locked position. The short side 6c does not have a horizontal lock. However, this type of mechanical lock results in a large waste of material due to the construction of the large lock elements.

Another known design of mechanical plate locking systems is shown in GB-A-1430429 and Figures 7a to 7b in the accompanying drawings. This system is based on a tongue-and-groove connection, has a special retaining hook on the extended edge of one side of the tongue-groove and has a corresponding retaining groove on the upper side of the tongue. The system requires considerable flexibility of the hook edge and disassembly is not possible without destroying the joining edges of the boards. Precise fitting requires difficult manufacturing and the joint geometry results in large waste of material.

Another known design of mechanical locking systems for floorboards is disclosed in DE-A-4242530. This locking system is also shown in Figures 8a-b in the accompanying drawings. This known locking system also has some disadvantages. Not only does it produce a large waste of material in production, but it also makes it difficult to economically produce high quality joints for floors where high quality is required. The undercut groove forming the tongue groove can only be produced by using a face milling cutter that moves along the joint edge. It is not possible to use large disc cutting tools to work the board from the edge.

For mechanical joining of various types of boards, especially floorboards, there are a number of improvement designs where there is little waste of material and where production is economical even when using boards on chipboard and wood base. WO 9627721, Figures 9a-b in the accompanying drawings, and JP 3169967, Figures 10a-b in the accompanying drawings, show two types of snap joints where there is little waste of material but have the disadvantage that they do not allow removal of the floorboards by tilting upwards. It is true that these fastening systems can be produced efficiently using large disc cutting tools, but they have the serious drawback that disassembly upwards causes such severe damage to the lock system that the plates can no longer be repositioned and mechanically locked.

Another known system is described in DE-A-1212275 and shown in Figures 1a-b in the accompanying drawings. This known system is suitable for sports flooring made of plastic materials and cannot be manufactured using large disc cutting tools for shaping a sharp cut groove. Also, this system cannot be disassembled by tilting upwards, although the materials have high elasticity, the lower and upper edges are rounded and the groove greatly deforms during tensile separation. This type of connection is therefore not suitable for chipboard-based floorboards when high quality joints are required.

The tongue-and-groove connection with the slope and tongue was designed according to US-A-1124228. The type of connection shown in Figures 12c-d in the accompanying drawings gives the possibility to mount a new board by pushing it downward through an inclined upwardly directed tongue on a previously laid board. Nails can be used to secure the new plate to be inserted, which are pushed diagonally down through the plate above an inclined tongue. In the embodiment of Figures 12a-b, this technique cannot be used because the dovetail connection is used. This technique certainly has little waste of material, but is not at all suitable for floating floors with individual floorboards which can be assembled and dismantled in a simple manner without being damaged and which have high quality joints.

DE-A-3041781 discloses and illustrates a lock system for joining plates, in particular when forming a circuit for roller skating and roller coaster made of plastic material.

This coupling system is also shown in Figures 13a-d in the accompanying drawings. The system includes a longitudinal groove at one edge of the plate and an upwardly curved tongue along the length of the opposite edge of the plate. In sectional view, the formed groove has a first portion which is defined as a portion having a parallel surface and is parallel to the main plane and a second inner portion which is trapezoidal or multi-angled, Figures 13a-b and Figures 13c-d in the accompanying drawings. In cross-section, the tongue has two parallel portions inclined to each other, wherein the portion closest to the center of the plate is parallel to the main plane of the plate and wherein the outer free portion is deflected upwards and corresponds to a respective surface portion of the trapezoidal groove portion.

The tongue and groove design and also the board edges are such that when such two boards are mechanically joined, a bond is obtained between the tongue surface portions and the corresponding surface of the cut groove along the entire upper side and the outer end of the tongue and along the lower side of the inner tongue part. which is parallel to the main plane as well as between the marginal surfaces of the joined plates above and below the tongue and groove. When the new plate is attached to a previously laid plate, the new plate is swung upward at a suitable angle to insert the inclined outer portion of the tongue into the outer parallel portion of the groove of the previously laid plate. Then the tongue is inserted into the groove, and the new plate is tilted down. Due to the angular shape of the tongue, some play in the first groove portion is necessary to allow insertion. Likewise, a certain degree of elasticity of the flooring material, which should be plastic according to the documentation, is necessary. In the laid down position, most of the tongue surface and the cut groove are contacted except for the lower, upwardly facing outer part of the tongue.

A serious drawback of the mechanical locking system according to DE-A-3041781 is its difficult manufacture. The manufacturing method proposes to use a milled foot-shaped end of the sponge with an outer portion that forms a trapezoidal inner portion of the tongue groove in cross-section. This manufacturing method is not very rational and, moreover, creates major tolerance problems if the manufacturing method should be used for floorboards or other wood panels to form wall panels or floor parquets with high quality joints.

As mentioned, a disadvantage of this present mechanical locking system is that inserting the inclined tongue into the groove requires considerable clearance between the tongue and the groove to be placed at an angle downwards, unless there is considerable flexibility in the plate material, see Figure 5 of DE-A-3041781 and Figure 13b in the accompanying drawings. In addition, this oblique downward movement cannot be performed if the new board and the previously placed board touch each other near the upper edge of the board above the tongue and groove such that the pivot point at an oblique downward position is located at this point.

A further disadvantage of this present mechanical locking system according to DE-A-3041781 when coupled to a fairly thick board of wood material is that moving a new board along a previously laid board in a laid or raised position is much more difficult to do with the panels interlocked in portions long pages. Even with very precise machining of wood or particle board, these surfaces are not naturally smooth enough to have protruding fibers that significantly increase friction. When laying parquet floors and the like. the floorboards are mostly of natural materials, which are usually 2 - 2.4 m long and 0.2 -0.4 m wide, damaged. This type of long boards is buckling and will therefore often deviate from the overall floating shape; banana shape. In these cases, it will be even more difficult to move the newly laid boards along the previously laid ones, if a mechanical locking connection of the boards on the short side is also required.

Another disadvantage of this present mechanical locking system according to DE-A-3041781 is that it is not very suitable for high-quality floors made of wood or chipboard materials and which therefore require a tight fit in the vertical direction between tongue and groove to prevent creaking.

WO 9747834 discloses floorboards with various types of mechanical locking systems. The locking systems considered to lock the long sides of the plates, Figures 2 -4, 11, 22-25 in the document, are designed so that they can be mounted and dismounted by fitting and tilting, while most interlocks with the short sides of the plates, Figures 5-10, is designed so that the interlocking occurs when pushed against each other for a latch connection, but these locking systems on the short sides of the plates cannot be dismantled without damage, often destruction.

Some of the boards that are the subject of the invention of WO 9747834 and which are designed for joining and dismounting by angular movement, figures 2-4 in WO 9747834 and figures 14a -c in the accompanying drawings, have a groove at one end and a strip below the groove below a joint plane where the upper sides of the two boards to be joined meet. The tape is designed to cover a substantial portion of the post-formed portion at the opposite edge of the plate so that two similar plates can be joined. A common feature of these floorboards is that the upper side of the tongue of the board and the corresponding upper end surface of the groove are planar and parallel to the upper side or surface of the floorboards.

The joining of the plates is intended to prevent tension through the joint plane and is achieved solely by means of the locking surfaces, on the underside of the tongue as well as on the upper side of the lower edge or strip below the groove. These locking systems also have the disadvantage that they require a portion of the tape to extend below the joint plane, which also causes waste of material at the joint edge where the groove is formed.

WO 9747834 also discloses mechanical fastening systems which comprise a circular arc-shaped tongue and a correspondingly shaped groove at the opposite edge of the floorboard - Figures 14d-14e in the accompanying drawings. When such a locking system is connected, the upper part of the tongue is opposite to the opening of the arch groove, after which it slides down. With this downward inclination, there is a large contact surface between all round surfaces of the groove and tongue. When this type of joint system is used with long wood panels or wood-based materials, it is very difficult to achieve a smooth and simple connection. Friction between the round faces, between the end of the tongue and the bottom of the groove, would require considerable force to move the plate along the next plate in their joined state. This present technique is certainly more suitable than that disclosed in the aforementioned DE-A3041781, but suffers from many drawbacks of this technique.

US-A-2740167 - Figures 15a-b in the accompanying drawings - disclose parquet boards or squares that are of wood and are formed at opposite ends by end portions that hook into each other when several parquet squares are laid in a row. One end portion has a downwardly curved hook and the opposite end portion has an upwardly curved hook. In order to insert a new parquet board, the lower part of the upwardly directed hook is bevelled. Parquet panels that are connected in a vertical joint plane are secured in a horizontal direction across the joint plane. An adhesive layer is also used for securing in the direction perpendicular to the top of the parquet boards, which is sprayed on the base on which the parquet floor is then laid. The hasty parquet board can then only be lifted before the adhesive layer adheres to it. Practically, such a parquet floor is permanently attached to the foundation after laying.

CA-A-2252791 shows and describes floorboards that are shaped with specially designed grooves along one long side and an additionally shaped tongue along the other long side. As shown in the patent specification and also in Figures 16a-b in the accompanying drawings, the tongue and groove are rounded and facing upwards to allow the board to be joined to another new board by positioning close to the laid and then simultaneously lifting and tilting after the groove has contracted. down through the upwardly pointing tongue while simultaneously joining and tilting down. From the moment the tongue and groove engage, it is difficult to reconnect the joined plates. Deviation from plane, t. j. a banana shape is another obstacle to joining two such plates. The risk of tongue damage is therefore great and the design causes high friction forces between tongue and groove surfaces.

US-A-5797237 discloses a latch locking system for joining parquet boards. In the accompanying drawings, Figure 17a is a cross-sectional view of two joined plates, Figure 17b shows how floorboards cannot be dismantled by tilting the plate upwards against another laid plate. Instead, as shown in Figure 4B of the patent specification, both the plate to be removed and the plate to be joined and remaining must be raised to pull the tongue out of the groove. The system is very similar to the aforementioned US-A-2740167, Figs. 15a-b in the accompanying drawings, but with the difference that the short lower edge is formed below the upper hook-like projection or edge. However, this short lower edge has no joining effect as long as there is a gap between the lower side of the tongue and the upper side of this edge when joining the plates. In addition, this clearance is required for the dismantling method as shown in Figure 17c. It is certain that the coupling system is latching, but first the laid plate is inclined slightly upward to release the tongue under the hook-shaped edge of the plate. This mechanical locking system can, as also stated in the patent specification, be manufactured using large disk cutting tools. There is no undercut groove whose upper and lower edges would fit against the inserted tongue and lock it vertically and horizontally with this locking system. Thus, the groove has a larger vertical space than the corresponding part of the tongue. The laid floor will therefore be able to move against the foundation, which can cause cracks in the joints and undesirable vertical movement. Nor can a good connection be achieved due to insufficient locking.

FRA-A-2675174 discloses a mechanical fastening system for ceramic panels having additionally shaped opposed edge portions, in which case separate tongue clips are used that mount at certain distances apart and which form a firm grip on the edge of the adjacent panel. The pivot connection system is not designed for disassembly, as is apparent from Figure 18a, and in particular from Figure 18b in the accompanying drawings.

Figures 19a and 19b show floorboards which are shaped according to JP 7180333 and are made by extrusion of a metallic material. After assembly, it is practically impossible to dismantle such floorboards with respect to the joint geometry, as shown in Figure 19a. Final Figures 20a and 20b illustrate another known jointing system disclosed in GB-A-2117813 for large insulated wall panels. This system is very similar to that of CA-A-2252791 and the system of WO 9747834 as shown in Figures 14d and 14e of the accompanying drawings. The system suffers from the same drawbacks as the latter two systems and is not suitable for the efficient production of wood or chipboard floorboards, especially when high joint quality and high floor quality are required. The construction according to said British publication uses metal parts as fasteners and is not openable upwards.

Figures 4a and 4b depict current Alloc ^w original and Alloc * Home systems with a designed tape that can deflect and clamp together.

The current fastening systems of Figures 9-16 can produce mechanical junctions with less waste than mechanical locking systems having protruding and machine-machined tapes. However, none of these systems satisfies the requirements completely and does not solve the problems that the present invention seeks to solve.

The sunken joints of Figures 7, 9, 10, 11, 12, 18, 19 cannot be locked or opened by rotary movement around the top of the joint edge, and the joints of Figures 8, 11, 19 cannot be manufactured in a rational manner by machining plate materials with large rotary tools. average.

The floorboards of Figures 12a-b cannot be folded or clamped, but must first be inserted and pressed parallel to the joint edge. The connection of Figures 12c-d cannot be a pinch. They may be inclined inwards, but in this case they must be manufactured with great play in the coupling system. The strength in the vertical direction is low because the upper and lower gripping surfaces are parallel. The joint is also difficult to manufacture and lock into position because it has no loose surfaces. In addition, it is proposed to attach the carnations to the base by using carnations which hammer obliquely into the floorboards above the tongue facing obliquely upwards.

The connection systems of Figures 6c-d, 15a-b, and 17a-b are examples of a connection that does not have a vertical lock, i.e., allows movement perpendicular to the top of the floor.

The beveled inward connection of Figures 14d-e has many drawbacks because it is made and constructed according to the principle that it should be tight and its upper and lower tongue and grooves follow a circular arc having a center at the upper joint edge, i. j. at the intersection of the joint plane and the surface plane. This connection does not have the necessary guide parts, the connection is difficult due to the angles because the construction is unsuitable and has large gripping surfaces. The result is disfigurement and the joint suffers drawer effect when inserting. The strength in the horizontal direction is too small because it depends on the small upper locking angle and the too small angular difference between the upper and lower gripping surfaces. In addition, the front and upper upwardly directed portion of the tongue groove is too small to sustain the forces required for high quality systems. Too large contact surfaces between the tongue and groove, the absence of the necessary free surfaces without contact and the requirement for tight seating throughout the joint makes it difficult to laterally move the floorboard along the joint edge, and also rational production with good tolerances is very difficult. And even horizontal interception is not possible.

The fastening system of Figures 16a-b has a structure that does not allow co-rotation without a considerable degree of material deformation, which is difficult to achieve with normal materials suitable for floorboards. Here again, all key and groove parts are in contact with each other. This makes it difficult to move the board laterally in the locked position or does not allow it at all. Rational working is also not possible since all surfaces are in contact. Nor is it possible to grip.

The coupling system of Figures 6a-b cannot rotate together because it is designed to rotate about two rotation points simultaneously. It has no horizontal lock in the keyway. All surfaces are in contact with each other and close to each other. In practice, the coupling system cannot be moved and manufactured in a rational manner. It is contemplated for use with the locking system shown in Figures 6c-d and is formed on an adjacent perpendicular edge and does not require lateral displacement to engage the connection.

The coupling system of Figures 8a-b has a tongue groove that cannot be produced by large diameter rotary cutting tools. It cannot clamp and be designed to prevent lateral displacement at the initial tension and close contact with the outer vertical portion of the tape.

The connection system of Figures 5a-b has two aluminum sections. It is not possible to produce the keyway with large diameter rotary cutting tools. The joining system is formed such that it is not possible to incline the new board inward at its upper joining edge when it is in contact with the upper joining edge of the previously laid board so that the inward inclination takes place around a pivot center at the intersection between the joining plane and the plane. In order to use the internal bevel in this present system, it is necessary to select a significant clearance that exceeds that acceptable for floors with high aesthetic and high quality requirements. The connection system of Figures 13a-d is difficult to manufacture because it requires contact over a large portion of the tongue and groove surface. It also makes lateral displacement in the locked position more difficult. The geometry of the joint makes it impossible to rotate upwards around the upper joint edge.

Other current systems are disclosed e.g. in DE 20013380U1, JP 2000179137A, DE 3041781, DE 19925248, DE 20001225, EP 0623724, EP 0976889, EP 1045083.

As can be seen from the above, the present systems have both disadvantages and advantages. However, no locking system is entirely suitable for the rational production of floorboards with a locking system that is optimal in terms of manufacturing technology, waste material, laying and lifting, and which, moreover, can be used for floors with the required high quality, strength and blowing properties. laid state.

It is an object of the present invention to satisfy this need and to provide such an optimal locking system for floorboards as well as optimal floorboards.

SUMMARY OF THE INVENTION

These objectives are achieved by a flooring system comprising floorboards, mechanically connected in the plane of the joint, having a core, a front side, a rear side and opposing connecting edges, one edge of which is shaped like a tongue groove, defined by upper and lower projections and lower the end and the second connecting edge are shaped as a tongue with an upwardly directed portion, the tongue groove, seen from the joint plane, having an undercut groove with an opening, an inner undercut portion and an inner locking surface, and at least portions of the lower projection formed integrally with the floorboard core; the tongue has a floor locking surface which is shaped to cooperate with the inner floor locking surface in the tongue groove of an adjacent floorboard when such two floorboards are mechanically connected to locate their connecting edges in the same surface plane and meet on a joint plane that is perpendicular to it, which The principle is that at least a greater part of the lower end of the tongue groove, viewed parallel to the surface plane, is located farther from the joint plane than the outer end of the tongue, the inner floor lock surface of the tongue groove is formed on the upper projection with the undercut tongue groove. cooperating with a corresponding tongue floor locking surface, wherein the tongue floor surface is formed with the upwardly directed portion of the tongue to jointly prevent the separation of two mechanically connected plates in a direction perpendicular to the joint plane, the lower projection having an abutment surface to cooperate with the corresponding tongue supporting surface further of the undercut groove, to cooperate against the mutual displacement of two mechanically connected floorboards in a direction perpendicular to the surface plane, and all parts of the lower projection that are connected to the core, viewed from the point where the surface plane and the plane of the intersection intersect are located externally of a plane which is further away from said point than the locking plane parallel to it and tangent to the cooperating tongue groove and tongue interlocking surfaces when said interlocking surfaces are most inclined against the surface plane, the upper projection and the lower lip and tongue of the connecting edges are designed to disconnect two mechanically connected floorboards by rotating one floorboard against the other upward about a pivot center just at the intersection point between the surface plane and the joint plane to disconnect the floorboard tongue and the tongue groove of another floorboard.

Advantageously, the system comprises an upper projection, a lower projection and a tongue of connecting edges for joining two floorboards with one floorboard, when the two floorboards are in contact with each other, rotating one relative to the other downward about a pivot center just at the intersection point between the surface and a joint plane to connect the tongue of one floorboard to the tongue groove of another floorboard.

It is also preferred that the system comprises an undercut tongue groove and a tongue for displacing a floorboard mechanically coupled to a similar board in a direction along the joint plane.

It is also preferred that the system also includes an undercut keyway and tongue for joining and detaching one plate to and from another plate by rotating one plate relative to the other in contact between the plates at a point on the connecting edges just adjacent the intersection between the surface plane and the joint plane.

It is also preferred that the system comprises an undercut tongue and tongue for joining and detaching the plates by rotating one plate against the other in contact between the plates at a point on the joint edges of the plates close to the intersection between the surface and joint plane without substantial contact between the tongue side surface plane and lower projection.

It is also advantageous that the system comprises an undercut groove and tongue for joining and disconnecting the plates by rotating one plate against the other in contact between the plates at a point on the joining edges of the plates just at the intersection between the surface plane and the joint plane; the surface plane and from the surface plane and the upper and lower projections respectively.

In the present system, the distance between the floor plane and the plane that is parallel to the outside of which all the parts of the lower projection that are connected to the core are located is at least 10% of the thickness of the floorboard.

It is preferred that the floor locking surfaces of the upper projection and the tongue form an angle of less than 90 °, but at least 20 °, respectively, with the surface plane. at least 30 °.

Any contact portion between the outer end of the tongue and the undercut groove has a smaller area in the vertical plane than the floor surfaces when mechanically joining the two plates. Preferably, the system comprises tongue and tongue groove joints for contacting surfaces between the tongue edges at most 30% of the edge surface of the tongue-supporting edge portion measured from the top of the floorboard to the bottom thereof when the two floorboards are joined.

Advantageously, the cooperating supporting surfaces of the tongue and the lower projection are at an angle in the range of 0 ° to 30 ° relative to the surface plane, respectively. at an angle of not less than 10 ° to the surface plane but not more than 20 ° to the surface plane.

In another preferred embodiment, a portion of the floor surface of the upper projection is located closer to the lower portion of the tongue groove, such as a portion of the abutment surfaces, wherein the floor surfaces of the upper projection and the tongue are substantially planar with at least parts of the surface intended to cooperate with each other. two boards connected.

In the present floor system, the lower projection is shorter than the upper projection and terminates further from the joint plane, wherein at least portions of the abutment surfaces of the lower projection and tongue are located at a greater distance from the joint plane than the inclined floor surfaces of the upper projection and tongue. The upper protrusion and the tongue have abutment surfaces to cooperate with each other in the locked state and which are located in the region between the plane of the joint and the locking surfaces of the tongue and the upper protrusion cooperating with each other in the locked state.

In a further preferred embodiment, the contact abutment surfaces are substantially planar and are inclined upwardly in the direction of the plane of the joint against the surface plane. It is also preferred that the contact abutment surfaces are substantially parallel to the surface plane.

The flooring system of the invention is designed to connect a previously laid floorboard to a new floorboard by pressing substantially parallel to the surface plane of the previously laid floorboard to clamp parts of the flooring system together.

It is preferred that the upper and lower portions of the tongue are made of different materials having different material properties and that the tongue groove and tongue are formed simultaneously with the floorboard.

In another preferred embodiment, the locking abutment surfaces (45, 65) have a greater angle relative to the surface plane than the tangent to the circular arc that touches the interlocking surfaces that bind to each other at a point closest to the lower portion of the undercut groove and at the point where the surface plane intersects with the plane of the joint.

In another preferred embodiment, the upper projection is thicker than the lower projection and the minimum thickness of the upper projection adjacent to the undercut portion is greater than the maximum thickness of the lower projection at the abutment surface.

Preferably, the surface of the abutment surfaces is at most 15% of the thickness of the floorboard and when the vertical tongue groove surface between the upper and lower projections, measured parallel to the joint plane and at the outer end of the abutment surface, is at least 30% of the floorboard thickness.

It is also preferred that the tongue has material properties other than the upper and lower projections. The upper projection is stiffer than the lower projection and is made of materials of different properties.

In another preferred embodiment, the flooring system further comprises a second mechanical lock comprising a floor groove that is formed on the underside of the tongue-supporting joint edge and is parallel to the plane of the joint, and a floor tape that is attached to the joint edge of the tongueboard below the tongue groove; it is substantially along the entire length of the connecting edge and has a strip-extending floor element for release in the floor groove of the adjacent plate when mechanically joining two such plates.

The present invention also relates to a floorboard for making a flooring system, by mechanically joining the board with identical floorboards in the plane of the joint, said floorboards having a core, a front side, a back side and opposed connecting edges, one of which is shaped like a tongue groove that the upper and lower projections having a lower end and the second connecting edge formed as a tongue with an upwardly directed portion, the tongue groove, seen from the joint plane, having an undercut groove with an opening, an inner portion and an inner locking surface and at least portions of the lower projection formed integrally with the floorboard core and the tongue having a floor locking surface which is shaped to cooperate with the inner floor surface in the tongue groove of an adjacent floorboard when such two floorboards are mechanically connected so that their front sides are located in the same surface plane; and meet at a plane of the joint that is perpendicular thereto, the essence of which is that at least a greater part of the lower end of the tongue groove, viewed parallel to the surface plane, is located farther from the plane of the joint than the outer end of the tongue; a projection with an undercut portion of the tongue groove to cooperate with a corresponding tongue floor surface, wherein the floor surface is formed with an upwardly directed tongue part to jointly prevent the separation of two mechanically coupled plates in a direction perpendicular to the joint plane; the tongue surface further away from the lower end of the undercut groove to interact against sliding of two mechanically connected floorboards in a direction perpendicular to the surface plane, and all parts of the lower projection which are connected to the core, viewed from the point where the surface plane intersects the other and the plane of the joint are located outside of a plane which is located farther from said point than the locking plane parallel to it and which is tangent to the cooperating tongue groove and tongue interlocking surfaces, when said interlocking surfaces are most inclined against the surface plane, wherein the upper projection and the lower projection and the tongue of the connecting edges are designed to disconnect two mechanically connected floorboards by rotating one floorboard against the other upward about the center of rotation just at the intersection point between the surface plane and the plane of the floorboard tongue splice .

The invention is based on the first recognition that suitable manufacturing methods, essentially machining, are used and tools whose diameter significantly exceeds the thickness of the board, which allow the production of improved shapes in a rational manner with high accuracy for wood, wood-based and plastic materials. and that this machining method can be performed in a tongue groove distant from the joint plane. This form of fastening system should be adapted to rational production, which should be made with very precise tolerances. However, such adaptation must not be to the detriment of other important characteristics of the floorboards and the locking system.

The invention is also based on a second knowledge which is based on knowledge of the requirements which must satisfy the optimal function of the mechanical coupling system. This knowledge is able to meet the requirements in a way that was not previously known, namely the combination of a) the construction of the coupling system e.g. with certain angles, radii, clearances, free surfaces and ratios between different parts of the system; and (b) making optimal use of the core or core material properties such as compressibility, elongation, bending, tensile strength and compressive strength.

The invention is further based on the third recognition that it is necessary to provide a manufacturing system with a low production cost, while at the same time maintaining function and strength or even in some cases improved by a combination of manufacturing technology, joint design, material selection and long and short side optimization.

The invention is based on the fourth knowledge that the connection system, manufacturing technology and measurement technology must be developed and modified so that critical parts requiring strict tolerances are as small as possible and also designed to allow measurement and control during continuous production.

Plurality of aspects of the invention are also applicable to known systems without these aspects being combined with the preferred locking systems described herein.

The invention also describes the basic principles that can make a tongue-and-groove connection by inwardly angling with the upper joining edges in contact with each other and where there is a minimum bending of the joining components. The invention also describes the properties of the material used to achieve high strength and low cost when combined with rotation and clamping, and also describes laying methods.

Various aspects of the invention will now be described in more detail with reference to the accompanying drawings, which illustrate various embodiments of the invention. Parts of the board according to the invention which correspond to the current boards of Figures 1-2 have the same reference numerals.

The invention is applicable to rectangular floorboards having a first pair of parallel sides and a second pair of parallel sides. To simplify the description, the first pair will be called long sides and the second pair will be short sides. It should be noted, however, that the invention can also be applied to square plates.

The high quality of the joint means the tight fit between the floorboards in the locked position, both vertically and horizontally. The joint should be free of visible gaps or level differences between the joined edges in both unloaded and normally loaded condition. On a high-quality floor, the joint gap should not be greater than 0.2 mm and the level difference should not be greater than 0.1 mm.

As will be apparent from the following description, it should be possible to lock down at least one side, preferably the long side, by tilting downwards. The downward tilt should be done by rotating about the center just adjacent the intersection between the planes of the floorboard surface and the joint plane, i. j. close to the "upper joint edges" of the boards when they touch each other. In other words, it is not possible to provide a joint that has tight joint edges in the locked position.

It should be possible to determine the rotation in a horizontal position where the floorboards are locked vertically without any play, as play can cause undesirable differences in levels between the joint edges. The inward inclination should be carried out in such a way that the floorboards are simultaneously directed against each other by tightly joining the edges and aligning any banana shape, i. j. deviations from the straight flat shape of floorboards. The locking element and the locking groove should have a guide, that is, they should cooperate in folding inwards. Folding down should be done with great care, without moving or squeezing the plates, so as not to damage the locking system.

It should be possible to tilt the long side up so that the floorboards can loosen. Since the plates in the initial position are connected by a tight joint between the edges, the upward inclination must therefore also be in contact with the upper joint edges and rotate on the joint edge. The possibility of tilting up is very important not only when changing floorboards or moving floors. Many floorboards are laid for testing, they do not fit correctly on doors, corners, etc. when installed. This is a serious drawback if the floorboard cannot easily detach without damaging the joint system. Also, the plate will not always be able to tilt inward, so it must be tilted again. In connection with the folding down, the tape is usually easily bent so that the locking element bends back and down and opens. If the joining system is not made up of suitable angles and radii, the plate may be locked after laying in such a way that lifting is not possible. The short side can be opened by tilting up after joining the long sides, usually it is pulled around the joint edge, but it is preferred that the short side can also be opened by tilting upwards. This is particularly advantageous if the boards are e.g. 2.4 m, which makes the short sides difficult to pull out. The upward deflection is done carefully without pushing and squeezing the plates, which could cause damage to the locking system.

It should be possible to lock the short sides by horizontal locking. This requires that the parts of the joint system be flexible and flexible. Even if the inclination inwardly of the long sides is much easier and faster than the engagement, it is preferable that also the long sides can engage because some traffic, e.g. a hinged door requires the boards to be connected horizontally.

If the floorboard is e.g. 1.2 x 0.2 m, each square meter of floor surface will have six times more joints of long sides than short sides. There is then a large amount of waste material, and expensive fasteners therefore do not have as important a role on the short side as on the long side.

In order to achieve high strength, the locking element must generally have a high locking angle so that the locking element cannot be plucked. The locking element must be high and wide to prevent it from breaking if it is subjected to a high tensile force such as floor shrinkage in winter due to the relative low humidity this time of year. This also applies to the material at the lock groove at the next plate. The short side of the joint should have a higher strength than the long side of the joint. Because the tensile load during winter shrinkage of the material is transmitted more to the shorter connecting length on the short side than on the long side.

Even under vertical loads, the plane of the slab should be maintained. In addition, there should be no movement in the joints, as the surfaces move under pressure when subjected to compressive forces, and, for example, the upper joint edges may cause a crack.

Creating the possibility to lock all four sides must allow the newly laid boards to be moved in a locked position along the previously laid board. This is accomplished using a force e.g. vigorously using a stone and hammer, without damaging the joint edges and creating a visible horizontal or vertical play on the existing joint system. Interchangeability is more important on the long side than on the short side. Because the friction is substantially greater here due to the longer joint.

There should be the possibility of rational production of the fastening system by using large rotary cutting tools that have extremely high precision and capacity.

Good function, manufacturing tolerance and quality require that the joint profile be continuously measured and checked. The critical parts of the mechanical coupling system should be designed in such a way that manufacture and measurement are easy. It should be manufactured with tolerances to one hundredth of a millimeter, measured with high accuracy, for example, so-called. profile projector. If the joining system is produced by linear cutting, the joining system will have the same profile along the entire edge, in addition to certain manufacturing tolerances. Therefore, the fastening system can be measured with great precision by cutting a sample from the floorboard and measuring it with a profile projector or measuring microscope.

However, rational production requires that the fastening system can be measured quickly and easily in a non-destructive manner, for example by using templates. It will be easier if the lock has as few critical parts as possible.

For floorboards to be produced in an optimal manner and with minimum waste, both the long and short sides should be adapted to their different characteristics as stated. For example, the long side should be adapted to be folded down and up, for positioning and relocation, while the short side should be adapted for snap and high strength. An optimally designed floorboard should have other fastening systems for the long and short sides.

Wood-based floorboards and, in general, floorboards containing wood fibers swell and contract due to varying humidity. Swelling and shrinkage usually begin from above, and the surface layers may therefore acquire a larger volume than the core, that is, the part that forms the joint system. In order to prevent the surface layer from lifting or rupture in the case of a high degree of swelling or joint slots upon excessive drying, the joint system should be designed to allow movement that will compensate for swelling and contraction.

BRIEF DESCRIPTION OF THE DRAWINGS

Figures la Figures 2a - c

Figures 3a - c Figures 4a - b Figures 5a - b Figures 6a - d

Figures 7a - b Figures 8a - b Figures 9a - b Figures 10a - b Figures 11a - b Figures 12a - d

Figures 13a - d Figures 14a - e Figures 15a - b Figures 16a - d Figures 17a - b Figures 18a - b Figures 19a - b

Figures 20a - b Figures 21a - b

Figure 22

Figures 23a-b Figures 24a-b Fig. 25 shows in three steps the method of mechanically joining the long sides of the floorboards according to WO 9426999 by tilting downwards.

show in three steps a snap-fit method for mechanically joining the short sides of floorboards according to WO 9426999.

show a floorboard according to WO 9426999 from above and below.

show two different embodiments of floorboards according to WO 9426999.

show a floorboard according to DE - A - 3343601.

show mechanical locking systems for long sides and short sides according to CA - A -0991373.

show mechanical locking systems according to GB - A - 143 042 9.

show floorboards according to DE - A - 4242530.

show a clamping connection according to WO 9627721.

show clamping connection according to JP 3169967.

show a clamping connection according to DE - A - 1212275.

show various embodiments of a tongue and groove key system according to US - A - 1124228.

show a mechanical fastening system for sports flooring according to DE-A-3041781. show one of the locking systems as shown in WO 9747834. show a parquet floor according to US-A-2740167.

show a mechanical locking system for floorboards according to CA-A-2252791. show a locking system for parquet floors according to US-A-5797237. show a jointing system for ceramic panels according to FR-A-2675174. show a jointing system for floorboards as described in JP 7180333 and are made by extrusion of a metallic material.

illustrating a joining system for large wall panels according to GB-A-2117813 schematically illustrating joining portions of a first preferred embodiment of a floorboard embodiment according to the present invention.

schematically illustrates the basic principles of downward rotation about the upper joint edge of the present invention.

show schematically the manufacture of the joining edge of the floorboard according to the invention, show a production variant of the invention in production.

shows a variant of the invention of engagement and upward rotation in combination with bending of the lower edge.

Figure 26 Figures 27a - c Figures 28a - c Figures 29a - b Fig. 30

Figures 31a - b Figures 32a - d Fig. 33 Fig. 34 Fig. 35

Figure 36

Figure 37 Figure 38 Figure 39

Figure 40 Figure 41 Pictures 42a - b Pictures 43a - c Figure 44 Pictures 45a - b Pictures 46a - b Pictures 47a - b Pictures 48a - b

Figure 49

Figure 50

Figures 51a-f Figures 52a-b Fig. 53 Figs. 54a-b Fig. 55 Figs. 56a-e Figs. 57a-e show a variant of the invention with a short edge.

show a method with up and down swivels.

show an alternative rotation method.

show the method of snapping.

shows how the long sides of two plates are joined with the long side of the third plate when the two plates are joined together by the short sides.

show two joined floorboards with a combination of the invention, show the inward rotation of the combined joint, show an example of shaping the long side of a parquet floor, show an example of shaping the short side of a parquet floor.

shows in detail an example of a long side jointing system for a parquet floor.

shows an example of a floorboard according to the invention, wherein the joint system is designed to be folded by bending and compression in the fastening material, showing a floorboard according to the invention.

show the production process in four steps.

illustrates a fastening system that is suitable for compensating for swelling and shrinkage of floorboard surface layers, showing a variant of the invention with a rigid, rigid tongue.

shows a variant of the invention, where the locking surfaces form the upper contact surfaces, show a variant of the invention with a long tongue, folding and pulling out, illustrating how the designed coupling system, adapted to be engaged, shows the engagement in the rotated position.

show a coupling system according to the invention with a spring tongue.

show a coupling system according to the invention with a double and flexible tongue.

show a connection system according to the invention with a lower edge partly made of a material other than the core material.

show a connection system that can be used as a snap-fit connection with a floorboard that is locked on all four sides.

shows a coupling system that can be used, for example, on the short side of a floorboard.

shows another example of a fastening system that can be used, for example, on the short side of a floorboard, showing a laying method.

display layouts using specially designed tools.

shows a short page connection.

show a snap on the short side.

shows a variant of the invention with a spring tongue that facilitates snapping on the short side, showing snapping of the outer corner portion of the short side, showing snapping of the inner corner portion of the short side.

DETAILED DESCRIPTION OF THE INVENTION

A first preferred embodiment of a floorboard I, U having a mechanical locking system according to the invention will now be described with reference to Figures 21a and 21b. For better understanding, the coupling system is shown schematically. It will be appreciated that better functionality will be achieved in other preferred embodiments, which will be described below.

Figures 21a, 21b show a schematic sectional view of the connection between the long side joint edge 4a of the board 1 and the long side opposite joint edge 4b of the other board L.

The tops of the plate are substantially on a common surface plane HP and the upper portions of the connecting edges 4a and 4b abut each other in the vertical plane of the joint VP. The mechanical locking system allows the plates to be locked to each other, both in the vertical direction D1 and in the horizontal direction D2, which is perpendicular to the joint plane VP. However, when laying the floor with the plates in a row side by side, one plate 1 / may be displaced along another plate 1 in the direction D3 along the joint plane VP - see Figure 3a. Such a displacement may, for example, be used to ensure mutual locking of floorboards which are laid in the same row.

To ensure the joining of the two portions of the joint edges perpendicular to the vertical plane VP and parallel to the horizontal plane HP, the floorboards at one edge have a tongue groove 36 in the joint edge 4a of the board inside the joint plane VP and tongue 38 formed on the other joint edge 4b joint plane.

In this embodiment, the board 1 has a wood core 30 that supports the wood surface layers on the front side 32 and a balancing layer on the back side 34. The board 1 is rectangular and has a second mechanical locking system on two parallel short sides. In some embodiments, the second locking system may have the same construction as the locking system on the long sides, but the locking system on the short sides may also have a construction other than that of the invention, or one of the prior art locking systems may be used.

By way of illustration, the floorboard may be of parquet type 15 mm thick, 2.4 m long and 0.2 m wide. However, the invention can also be used for square parquet or boards of other dimensions.

The core 30 may be of the lamella type and consist of narrow wooden blocks of wood species that are not expensive. The surface layer on the front side 32 may have a thickness of 3-4 mm and consists of a decorative type of hardwood and is painted. The balancing layer on the back 34 may consist of a 2 mm thick veneer layer. In some cases, different types of wood materials can advantageously be used in different parts of the floorboard for optimal properties in the individual parts of the floorboard.

As noted, the mechanical locking system of the invention comprises a tongue groove 36 in one joint edge 4a of the floorboard and a tongue 38 at the opposite joint edge 4b of the floorboard.

The tongue groove is defined by the upper and lower projections 39, 40 and is in the form of a cut groove with an opening between the two projections 39, 40.

The various portions of the tongue groove 36 are best seen in Figure 21b. The tongue groove is formed in the core 30 and extends from the edge of the floorboard. Above the tongue groove there is an upper edge portion or joint edge surface 41 that terminates on the surface plane HP. Inside the keyway opening is an upper balancing or support surface 43, which in this case is parallel to the plane of the surface HP. This balancing or support surface passes into an inclined locking surface 45 having a locking angle A with the horizontal plane HP. Inside the locking surface is a portion of the surface 46 that forms the upper boundary surface of the undercut portion 35 of the tongue groove. The tongue groove further has a lower end 48 that faces downwardly to the lower projection 40. On the upper side of this projection there is a balancing and support surface 50. The outer end of the lower projection has a connecting edge surface 52 which in this case slightly extends beyond the plane of the VP.

The shape of the tongue is also best seen in Figure 21b. The tongue is made of core material or core 30 and extends beyond the joint plane VP when this joint edge 4b is mechanically connected to the joint edge 4a of the adjacent floorboard. The connecting edge 4b also has an upper connecting portion or an upper connecting surface 61 that extends downwardly along the joint plane VP down to the tongue root 38. The upper side of the tongue root has an upper gripping or support surface 64 which in this case reaches the chamfered locking surface 65 upwards. the pointing portion 8 just to the tip of the tongue. The locking surface 65 passes into the guide surface 66, which terminates in the upper surface 67 of the upwardly directed tongue portion 8. The surface 67 is followed by a bevel which can serve as a guide surface 68. This is directed towards the tongue top 69. At the lower end of the apex 69 there is another guide surface 70 that faces obliquely downwardly to the lower edge of the tongue and the gripping or abutment surface 71. The gripping surface 71 is intended to cooperate with the abutment surface 50 of the lower projection to mechanically connect the two floorboards so the sides are on the same surface plane HP and meet in the plane of the joint perpendicularly so that the upper joining edge surfaces 41 and 61 of the plates are joined to each other. The tongue has a lower connecting surface 72 that extends to the lower side.

In this embodiment, the gripping and abutment surfaces 43, 64 are separated in the tongue groove and on the tongue, which, in the locked state, engage with each other and act together with the lower abutment surfaces 50 and 71 on the lower tongue protrusion to be locked perpendicularly to the surface. HP plane. In a further embodiment to be described, the locking surfaces 45 and 65 act to lock together in a direction D2 that is parallel to the HP surface plane and as support surfaces for movements acting in the opposite direction in a direction D2 perpendicular to the surface plane. In the embodiment of Figures 21a and 21b, the locking surfaces 45, 65 and 43, 64 cooperate as the upper support surfaces of the system.

As shown in the drawing, the tongue 38 extends beyond the plane of the joint VP and has an upwardly facing portion U at the free end or apex 69. The tongue also has a locking surface 65 that is shaped to cooperate with the inner locking surface 45 of the tongue groove 36 of an adjacent floorboard. when two such plates are mechanically joined such that their front sides are on the same surface plane HP and are in contact with the plane of the joint VP which is perpendicular thereto.

As can be seen from Figure 21b, the tongue 38 has a surface 52 between the locking surface 51 and the joint plane VP. When the two floorboards are joined, the surface 52 engages the locking surface 45 of the upper projection 8. To facilitate insertion of the tongue into the cut groove by twisting in or snapping in, the tongue, as shown in Figures 21a and 21b, may have a bevel 66 between the locking surface 65 and the surface. In addition, the bevel 68 may be positioned between a portion of the surface 57 and the tip of the tongue 69. The bevel 66 may assist as a guide at a smaller inclination angle to the surface plane than the angle A of the locking surfaces 43 and 51.

The tongue support surface 71 in this embodiment is substantially parallel to the surface plane HP. The tongue has a bevel 70 between this support surface and the tip of the tongue 69.

According to the invention, the lower projection 40 has a support surface 50 for interacting with a corresponding support surface 71 of the tongue 38 at a distance from the lower end 48 of the undercut groove. If the two plates are connected to each other, the connection is between the abutment surfaces 50 and 71 and the abutment surfaces 43 of the upper projection 39 and the corresponding retaining or abutment surface 64 of the tongue. In this way, the plates are locked in the direction D1 perpendicular to the HP plane.

According to the invention, at least a greater part of the lower end 48 of the cut groove must be analogous to the surface plane HP, be positioned farther from the joint plane VP than the outer end or apex 69 of the tongue 38. With such construction, production is greatly simplified. boards along the joint plane are facilitated.

Another important feature of the mechanical locking system of the invention is that all the core-engaging portions of the lower protrusion 40, viewed from point C where the surface plane HP and the joint plane VP intersect, are outside the plane LP2. This plane extends further from said point C, such as the locking plane LP1, which is parallel to the plane LP2 and is tangent to the interlocking interlocking surfaces 45, 65 of the carved tongue groove 36 and the tongue 38, wherein the interlocking surfaces are inclined relative to the surface plane. HP. Due to such a construction, the groove, which will be described in more detail below, can be shaped by rotary cutting tools for machining parts of the floorboards.

Another important feature of the mechanical locking system according to the invention is that the upper and lower projections 39 and 40 and the tongue 38 in the connecting edges 4a and 4b are designed to be able to detach two mechanically connected floorboards by rotating one plate upwardly against the other. around a pivot point near the intersection point C between the surface plane HP and the plane of the joint VP so that the tongue of this floorboard is pivoted from the cut groove of the next floorboard.

In the embodiment of Figures 21a and 21b, such disengagement is accomplished by gently bending downwardly toward the lower projection 40. In other, preferred embodiments of the invention, no bending of the lower projection is required when joining and uncoupling the floorboards.

In the embodiment of Figures 21a and 21b, the joining of two floorboards according to the invention can be carried out in three different ways.

One method is to place the plate H on the foundation and move against the previously laid plate 1 until the narrow apex 69 of the tongue 38 is inserted into the hole of the cut groove. Then, the floorboard 11 is swung upwards until the upper portions 44 and 61 of the boards on both sides of the plane of the joint touch each other. While this contact is maintained, the plate is folded down by pivoting about the center of rotation C. Insertion is effected by a taper 66 of the tongue, sliding along the locking surface 45 of the upper protrusion 39 and at the same time the taper 70 of the tongue 38 slides against the outer edge of the upper side of the lower protrusion 40. the system can then be opened by tilting the floorboard about the center of rotation C near the intersection of the surface plane HP and the joint plane VP. The second locking method is accomplished by moving the new board with its tongue edge 4a with the tongue groove formed opposite the tongue edge 4b of the previously laid tongue plate. Then, the new plate is rotated upwards until the plates contact the upper joint surfaces 41 and 61 tightly at the intersection between the surface plane and the joint plane, then the plate is rotated downward to join the tongue and tongue groove until the final position is reached. According to the following description, the floorboard can also be attached with one board slid upwardly against the other board.

A third way of joining the floorboards in this embodiment of the invention is that the new board U is horizontally displaced over the previously laid board 1 by inserting the tongue 38 with its locking element or the upwardly directed portion into the tongue groove 36, lower the elastic projection 40 is slightly bent down so that the upwardly directed portion 8 of the lock element engages in the undercut portion 35 of the tongue groove. Also in this case, the lift-up disconnection can be performed as described.

On engagement with the engagement, there may be a slight bending of the upper projection 39 as well as some small compression of all the parts in the groove 36 and the tongue 38 which are in contact with each other during the pivoting. This facilitates engagement and can be used to create an optimum coupling system.

In order to facilitate the production of internal chamfers, upward chamfers, engagement and disassembly in the locked position and to minimize the risk of rupture, when locked together and in locking and unlocking, not all surfaces that are critical to the tight connection of the upper joining edges may be and to form a vertical and horizontal connection. This allows production without requiring high tolerances in these joint portions and reduces friction on lateral displacement along the joint edge. Examples of surfaces or parts of the joint system that should not be in contact with each other in the locked position are 46-67, 48-69, 50-70, and 52-72.

The bonding system according to the preferred embodiment may comprise several different combinations of materials. The upper protrusion 39 may be made of a rigid and hard top surface layer 32 and a softer lower portion that is part of the core 30. The lower protrusion 40 may be of an equally soft upper portion of the core 30 and also the soft rear portion 34 may be of another type of wood. The fiber direction of these three types of wood may vary.

This material is used to secure the fastening system and is intended to facilitate it by its properties. The locking element according to the invention is therefore placed closer to the upper hard and rigid part, which is therefore resilient and compressible only to a certain extent, while the clamping function is formed in the soft and resilient lower part. It should be emphasized that the joining system can also be made in a homogeneous floorboard.

Figure 22 schematically illustrates the basic principles of inward rotation about a point C at the upper joint edge using the present invention. Figure 22 schematically illustrates how a locking system could be constructed to allow inward rotation about the upper joint edge. In this inward rotation, portions of the joint system rotate in a known manner along a circular arc with the center C just at the intersection between the surface plane HP and the plane of the joint VP. If a large clearance is allowed between all parts or a significant deformation is possible during inward rotation, the groove and tongue can be formed in various ways. If, on the other hand, the fastening system must have contact surfaces that prevent vertical and horizontal separation without any play between the gripping and support surfaces and if material deformation is not possible, then the fastening system must be designed according to the following principles.

The upper portion of the joint system is formed as follows: C1B is a circular arc with a center C at the top of the surfaces 41, 61 of the upper joint edges and which in this preferred embodiment intersects the contact point between the upper projection 39 and the upper part of the tongue 38 at point P2. All other contact points between P2, P3, P4 and P5 between the upper projection 39 and the upper part 8 of the tongue 38 and between this intersection of P2 and the vertical plane VP are located on or inside this circular arc C1 B, while all other contact points from P2 to P1 between the upper projection 39 and the upper part of the tongue 38 and between this intersection P2 and the outer part of the tongue 38 are located on or on the outside of this circular arc C1B. These conditions can be met for all contact points. In relation to the contact point P5 and the circular arc CIA, all other contact points between P1 and P5 are located outside the circular arc CIA, in relation to the contact point P1 all other contact points between P1 and P5 are located inside the circular arc CIC.

The lower part of the coupling system is formed according to corresponding principles. C2B is a circular arc that is concentric to the circular arc CIA and which in this preferred embodiment intersects the contact point between the lower projection 40 and the lower part of the tongue 38 at point P7. All other contact points between P7, P8 and P9 between the lower projection 40 and the lower part of the tongue 38 and between this intersection of P7 and the vertical plane are located on or outside the circular arc C2B and other contact points between P6, P7 and between the lower projection 40 and the lower a portion of the tongue 38 and between this intersection point P7 and the outer portion of the tongue 38 are disposed on or within this circular arc C2B. The same applies to the contact point P6 with the circular arc C2A.

The coupling system designed according to this preferred embodiment may have good inward rotation properties. It can easily be combined with the upper gripping and abutment surfaces 43, 64, which can be parallel to the horizontal plane HP and which therefore can provide excellent vertical locking.

Figures 23a, 23b show how the coupling system of Figures 21a, 21b can be manufactured. Typically, the prior art floorboard 1 is placed with its front side 2 down on a ball bearing cutter chain that transports the board with extremely high precision through a plurality of milling cutters, for example having a tool diameter of 80-300 mm, which can be assembled at an optimum angle to the horizontal plane of the plate. However, for easier understanding and comparison with other figures in the drawings, the floorboard is shown with its HP surface plane directly upwards. Figure 23a shows how the first tool in the TP1 position carves a traditional tongue groove. In this case, the tool operates at the tool angle TA1, which is 0 °, t. j. is parallel to the horizontal plane. The axis of rotation of the RAI is perpendicular to HP. The undercut is performed by a second tool, wherein the position of TP2 and the tool design are such that the undercut portion 35 is formed without breaking the lower projection 40. In this case, the tool has an angle TA2 equal to the angle of the locking surface 45 in the undercut portion 35. is possible because the locking plane LP1 is located at such a distance from the joint plane that the tool can be inserted into a pre-formed tongue groove. Therefore, the thickness of the tool cannot be greater than the distance between the two planes LP1 and LP2, as mentioned with reference to Figures 21a and 21b. The production technology is identical to the current technology.

Figures 24a and 24b illustrate another embodiment characterized in that the joint system is formed entirely according to the basic principle of inward rotation about the upper joint edge as described. The locking surfaces 45, 65 and the lower abutment surfaces 50, 71 are planar in this embodiment, but may have different shapes. C1 and C2 are two circular arcs with a center C at the upper end of the surface 41, 61 of the joined joint edges. The smaller circular arc C1 touches the lower contact point closest to the vertical plane between the locking surfaces 45, 65 at point P4, which has a tangent TL1 coincident with the locking plane LP1. The locking surfaces 45, 65 have the same slope as this tangent. The larger circular arc C2 contacts the upper contact point between the lower abutment surfaces 50, 71 closest to the inner part of the tongue groove at point P7 having a tangent TL2. The support surfaces 50, 71 have the same slope as this tangent.

All the contact points between the tongue 38 and the upper projection 39, which lie between the points P4 and the vertical plane VP, satisfy the condition that they lie inside or on the circular arc C1, while all 16 contact points that lie between P4 and the inner part of the tongue groove - in this embodiment, only the locking surfaces 45, 65 satisfy the condition that they lie on or from the outside of C1. Similar conditions are met for the contact surfaces between the lower projection 40 and the tongue 38. All contact points between the tongue 38 and the lower projection 40 that lie between the point P7 and the vertical plane VP - in this case only the lower support surfaces 50, 71 from the outside of the circular arc C2, while all the contact points lying between the point P7 and the inner part of the tongue groove lie on or inside the circular arc C2. In this embodiment, there are no contact points between P7 and the lower end 48 of the tongue groove.

In particular, this embodiment is characterized in that all the contact surfaces between the contact point P4 and the plane of the joint VP, in this case point P5 and the lower end 48 of the tongue groove, respectively, lie inside and out of respectively circular arc C1 and thus they are not on the circular arc C1. The same applies to the contact point P7, where all the contact points between P7 and the vertical plane VP, in this case P8 and the lower end 48 of the tongue groove, respectively, lie on the outside and inside, respectively, the circular arc C2 and thus they are not on the circular arc C2. As can be seen from the dashed line portion of Figure 24a, the coupling system may, if this condition is met, be designed such that the inward rotation is performed freely during the entire rotational movement determined by the plates tightly locked or by pressure when they assume their final horizontal position. Thus, the invention allows a combination of in-and-out rotation without resistance and high-quality locking. If the lower abutment surfaces 71, 50 are made with a slightly smaller angle, the joining system has only two of said contact points P4 on the upper projection and P7 on the lower tongue between the tongue groove 36 and tongue 38 throughout the inward rotation until complete locking occurs. and throughout the upward rotation until the plates are free from each other. Locking with clearance or with only direct contact is a considerable advantage, since the friction will be small and the plates can easily rotate in and up without having to push and push each other at risk of damaging the coupling system. Precise and tight fit, especially in the vertical direction, is very important for strength. If there is a play between the gripping or abutment surfaces, the plates will slide on the locking surfaces under tensile load until the lower gripping or abutment surfaces assume a tight fit position. Therefore, the clearance will result in both a gap and a different plane between the upper joint edges. By way of example, tight fit with high strength is achieved when the locking surfaces have an angle of about 40 ° to the HP surface plane and the lower engagement and support surfaces have an angle of about 15 ° to the HP surface plane.

The locking plane LP1 has a locking angle A with a horizontal HP plane of 39 ° in Figure 24a, while a support plane TL2 along a support surface 50.2i has a VLA angle of 14 °. The angle difference between LP1 and the support plane TL2 is 25 °. A large locking angle and a large angle difference between the locking angle and the supporting angle is desirable because it results in a large horizontal locking force. The locking surface and the support surface can be made as arcuate, stepped with several angles and the like, but. it makes production difficult. As mentioned, the locking surfaces also have upper abutment surfaces or are completed with separate upper abutment surfaces.

Even if the locking surfaces and support surfaces have contact points that deviate slightly from these basic principles, they can rotate inwards at their upper joint edges if the joint system is modified such that their contact points or surfaces are small relative to the floor thickness and so that the compression, elongation and bending properties of the flooring material are maximally utilized in combination with very small clearances between the contact surfaces. This can be used to increase the locking angle and the difference between the locking angle and the supporting angle.

The basic principle of inward rotation therefore indicates that the critical parts are the locking surfaces 45, 65 and the lower abutment surfaces 50, 71. It also points out that the degree of freedom is large with respect to the construction of other parts, for example the upper abutment surfaces 43, 64. , a guide groove 44, a guide 67 of a lock element 8, the inner parts 48, 49 of the tongue groove 36 and the lower projection 40, the guide and the outer parts 51 of the lower projection as well as the outer / lower parts 69, 70, 72 of the tongue. These should deviate from the shape of the two circular arcs of Cla C2 and there may be free space between all parts except the upper abutment surfaces 43, 64, so that these parts are not in contact with each other in the locked position as well as during inward and upward rotation. This greatly facilitates manufacturing, as these parts can be formed without great tolerance requirements, it helps to gently rotate inwards and upwards, and also reduces the friction in the joint as the joint plates are moved laterally along the joint planes VP - in the direction D3. By clearance is meant connecting parts that are not intended to provide vertical or horizontal displacement and displacement along the joint edge in the locked position. Thus, loose wood fibers and easily deformable contact points should be considered equivalent to free surfaces.

Rotation around the upper joint edge can be facilitated, as noted, if the joint system is designed such that there is little play over all said locking surfaces 45 when pressing the joint edges of the plates together. The design clearance also facilitates lateral displacement in the locked position, reduces the risk of creaking and gives a greater degree of manufacturing freedom, allows rotation inwardly of locking surfaces that tend to be more inclined than the LP1 tangent, and promotes leveling of the undulating top edges. The clearance yields significantly less joint gaps on the top of the plates and significantly less vertical displacement, there is no clearance between the gripping and abutment surfaces, which due to this volley is small due to the fact that sliding in the tensile position follows the angle of the lower abutment surface. j. an angle that is substantially less than the lock angle. This minimum clearance, if any, between the locking surfaces can be very small, for example only 0.01 mm. In the normal coupled position, it may not be, e.g. j. is equal to 0, the joining system can be designed so that the play occurs only when the joining edges of the boards are pressed together. It has been found that even greater clearance, about 0.05 mm, results in high joint quality because the joint gap, which is detected on the HP surface plane and which can increase in the tensile position, is barely visible.

It should be emphasized that the connection system can be constructed without any play between the locking surfaces.

The clearance and compression of the material between the locking surfaces and the bending of the connecting parts in the locking surfaces can be readily measured indirectly when the joint system is tensile, the joint gap at the upper joint edges 41, 61 is measured at a predetermined load that is less than the strength of the joint system. It is understood by strength that the fastening system does not disconnect or fail to engage. A suitable tensile load is about 50% strength. A non-limiting standard value for the long side of a joint is considered to be a strength exceeding 300 kg per common meter of joint. The short side of the joint should have even greater strength. A parquet floor with a suitable joint system according to the invention can withstand a tensile load of 1000 kg per meter of joint. The high quality joint system should have a joint gap between the surfaces 41, 61 of the upper joint edges of about 0.1-0.2 mm at a tensile load of approximately half the maximum strength.

The joint gap should be reduced when the load ceases. The design clearance and material deformation can be determined under varying tensile loads. In the case of a lower tensile load, the joint gap is the basic measure of the design clearance. In the case of higher loads, the joint gap increases due to material deformation. The connection system may also be designed with a bias and a press fit between the locking surfaces and the support surfaces so that said connection gap is not visible in the case of said load.

The geometry of the joint system, the gap between the locking surfaces in combination with the compression of the material by rounding the surfaces 41, 61 of the upper joint edges, can also be measured by a joint that is seen across the joint edge. Because the joint system is manufactured by linear machining, it will have the same profile along the entire joint edge. The only exception is the manufacturing tolerance in the form of non-parallelism due to the fact that the board can be inverted or moved vertically or horizontally when passing through different milling machines of the machine. Normally, however, two samples from each joint edge give a very reliable picture of the appearance of the joint system. After the samples have been ground and cleaned of the remaining fibers so that the joint profile is clearly visible, they can be analyzed for joint geometry, material compression, bending, etc. For example, the two joint portions may be compressed by a force that does not damage the system, in particular all surfaces 41, 61 of the upper joint edges. The clearance between the locking surfaces and the joint geometry can be measured with a measuring microscope with an accuracy of 0.01 mm or less, depending on the instrument. If stable and modern machines are used in production, it is usually sufficient to determine the average clearance, joint geometry and the like. measuring the profile on two small parts of the floorboard.

All measurements can be made at a normal relative humidity of about 45%.

Also in this case, the lock element or the upwardly directed tongue portion 8 has a guide portion 66. The guide portion of the lock element comprises portions having a slope less than the slope of the lock surfaces, and in this case also the slope of the tangent TL1. A suitable degree of inclination of the tool forming the locking surface 45 is given by TA2, which in this embodiment is identical to the tangent TL1.

Also, the tongue groove locking surface 45 has a guide portion 44 which, while rotating inwardly, interacts with the tongue guide portion 66. Also, this guide portion 66 comprises portions that have less inclination than the locking surface.

At the front of the lower projection 40 there is a rounded guiding portion 5i which cooperates with a radius in the lower part of the tongue with the lower gripping surface 71 at point P7 and which facilitates the inward rotation.

The lower projection 40 may be resilient. Along with the inward rotation, a small compression at the contact points between the lower portions of the tongue 38 and the lower lip can be used. As a rule, this compression is considerably less than it may be in the case of lock systems, because the lower projection 40 has significantly better resilient and tenacity properties than the upper projection 39 and the tongue 38. Upon and downward twisting, the projection may bend downwards. The bending capability of only one tenth of a millimeter or a little more, together with material compression and small contact surfaces, provides suitable conditions for forming, for example, lower abutment surfaces 50, 71, so that they may have a slope less than tangent TL2, and at the same time. The elastic projection should be combined with a relatively large locking angle. At a small locking angle, a greater tensile load will push the projection downwards, creating an undesired joint gap and level differences between the joint edges.

The tongue groove 36 and tongue 38 have guide portions 42, 51 and 68, 70 which insert the tongue into the groove and facilitate the engagement and rotation inwards.

Figure 25 shows variants of the invention where the lower projection 40 is shorter than the upper projection 39 and is therefore located away from the vertical plane VP. The advantage is that there is a higher degree of freedom in designing the lock surface 45 with a large TA tool angle, while at the same time relatively large tools can be used. To facilitate engagement by rotating the lower projection 40 downwards, a tongue groove 36 may be made deeper than the required space for the tongue tip 38. The dotted connecting edge 4b shows the relative position of the system portions relative to each other when joining inwardly around the upper joint edge. the edge 4b shows the relative position of the parts when joined by engaging the tongue into the tongue groove when moving the joint edge 4b directly opposite the joint edge 4a.

Figure 26 shows another variant of said basic principle. The joint system is here formed by locking surfaces which have a 90 ° inclination to the HP surface plane and which are significantly more chamfered than the tangent TL1. However, this preferred locking system is openable by rotating upwardly the locking surfaces, which are extremely small and the locking connection is essentially only direct contact. If the core is hard, then this locking system provides high strength. The design of the locking element and the locking surfaces allows for engagement only by a very small bending of the lower projection downwards, as shown in the drawing in dotted lines. Figures 27a-c show a method of laying inwards. For ease of description, one plate is called a grooved plate and the other a tongue plate. Practically the two boards are the same. The laying method assumes that the tongue plate lies flat on the floor base either as a loose plate or connected to other boards by one, two or three sides, depending on where it is situated in the subassembly / row. The groove plate is positioned with its upper projection 39 partially above the outer parts of the tongue 38 so that the upper joint edges contact each other. Thereafter, the groove plate is pivoted downward to the flooring base while pressing against the tongue edge of the tongue plate until the final locking according to Figure 27c occurs.

The sides of the floorboards sometimes have some bending. The groove plate is then pressed and rotated downwardly so that portions of the upper protrusion 39 are in contact with portions of the upwardly directed portion 8 or the tongue lock element, and portions of the lower protrusion 40 are in contact with a portion of the lower portion of the tongue. In this way, the bending of the sides is straightened and then the plates can be rotated to their final position and locked.

Figures 27a-c show that the inward rotation can be performed with clearance or alternatively only by contact between the upper part of the tongue groove and the tongue or by direct contact between the upper and lower parts of the tongue and tongue groove. Direct contact in this embodiment occurs at points P4 and P7. The inward rotation can easily be carried out without any particular resistance and can be characterized by a very tight connection and locking of the floorboards to their final position with high quality vertical and horizontal connections.

In summary, the downward rotation is practiced in the following manner. The groove plate moves at an angle relative to the tongue plate until the tongue groove is threaded over a portion of the tongue. The groove plate is pushed against the tongue plate and is tilted downwards by applying, for example, pressure on the center of the plate and then on both edges. When the upper joining edges of the entire board are close to or touch each other and the board has an angle to the flooring, a final folding down is performed.

When the plates are connected, they can be disengaged in the locked position in the connection direction, i. j. parallel to the joint edge.

Figures 28a-c show how a corresponding position can be made by sliding the tongue plate diagonally into the groove plate.

Figures 29a-b show a snap connection. If the plates move horizontally against each other, the tongue is inserted into the groove. During continuous pressing, the lower projection 40 of the fire and the upwardly directed portion 8 of the locking member engage in the locking groove or undercut portion 35. It should be noted that the preferred coupling system illustrates the basic principles of engagement with the resilient lower projection. Of course, the fastening system must be adapted to the material bending possibilities and the depth of the tongue groove 36, the height of the locking element 8 and the thickness of the lower projection 40 and should be dimensioned so as to engage. The basic principles of the joining system of the invention, which is more suitable for using materials with a lower degree of flexibility and flexibility, will be clear from the following description and Figure 34.

The described laying methods can be freely used on all four sides and can be combined with each other. After laying on one side, side shifting is usually performed in the locked position.

In some cases, for example, in the case of a swiveling inward of the short side as the first operation, the two plates are usually rotated upwards. Figure 30 shows a first plate 1 and an upwardly facing second plate 2a and an upwardly facing new third plate 2b, which by its short side is already connected to the second plate 2a. After the new plate 2b is laterally moved along the short side of the second plate 2a in an upturned and short side locked position, the two plates 2a and 2b are folded down connected and locked on the long side to the first plate I. For this method to work, it is necessary for the new plate to be inserted with its tongue into the tongue groove, then the plane is moved parallel to the second plane 2a and when the second plane has a part of the tongue partially inserted into the tongue groove and its upper joint edge is in contact with the upper joint edge of the first plane I FIG. 30 shows that the connection system can be made with such a tongue groove, tongue and lock element design that it is possible.

All laying methods require relocation in the locked position. The only exception for lateral movement in the locked position is the case where some boards are joined on their short sides and then a number of stacks are laid simultaneously. But this is not a very rational method of laying.

Figures 3a, 3b show part of a floorboard with a combined joint. The tongue groove 36 and tongue 38 may be shaped according to one of the above embodiments. The groove plate has on its underside a locking strip 6 with a locking element 8b and a locking surface 10. The tongue side has an undercut portion 35 according to the known embodiment. In this embodiment, the locking element 8b will operate with the relatively long guide portion 9 as a separate guide during the first inward rotation part, which greatly facilitates this first inward rotation part during insertion and aligns all banana shapes. The locking element 8b causes the automatic placement and compression of the floorboards until the tongue guiding portion is caught by the locking groove formed by the undercut portion 35 and the final locking is performed. Laying is greatly facilitated and the connection will be very strong by connecting two locking systems. This joint is very suitable for connecting large floor areas, especially in public rooms. In this illustration, the tape 6 is attached to the groove side but can also be attached to the tongue side. The location of the tape 6 is therefore optimal. In addition, the joint can be made snap-in when turned up and then laterally displaced in the locked position. This joint can optionally be used in various variants on both the long and short sides and can be arbitrarily combined with all joint variants described herein and with other known systems.

A convenient combination is the short-side snap system without aluminum tape. This may in some cases facilitate production. The tape that attaches after manufacture also has advantages because it can form part or even the entire lower protrusion 40. This allows a large degree of freedom to be formed by cutting tools such as the upper protrusion 39 and the shaping of lock surfaces with large lock angles. The locking system of this embodiment can of course be made snap-fit and can be made with an optional tape width, for example, tape 6 that does not protrude beyond the outer portion of the upper protrusion 39, as in the embodiment of Figure 50. The tape need not be continuous throughout the length of the joint, but may consist of several small parts that are spaced apart on both the long and short sides.

The lock element 8b and its undercut portion 35 may be shaped by various angles, heights and radii, which may be arbitrarily selected so as to either prevent separation and / or facilitate rotation inward or snap-in.

Figures 32a-d show four steps of inward rotation. The wide tape 6 allows the tongue 38 to be easily laid on the tape at the beginning of the inward rotation. The tongue can then automatically slide down into the tongue groove 36 while folding downwards. Similar layering can be done with a tape 6 inserted under the tongue plate. All the laying functions that have been described can be used with floorboards in combination with this preferred system.

Figures 33 and 34 show a production-specific and optimized joining system for all wood core floorboards. Figure 33 shows how the long side can be shaped. In this case, the joining system is optimized in particular with regard to inward rotation, upward rotation and low waste of material. Fig. 34 shows how a short side can be shaped. In this case, the coupling system is optimized in particular with respect to snap-fit and high strength. The differences are as follows. The tongue 38 and the locking element of the short side 5a are longer when measured in the horizontal plane. This provides a higher shear strength of the upwardly directed portion 8 of the lock element. The tongue groove 36 is deeper on the short side 5b, which helps the lower projection more to bend down. The locking element 8 is lower on the short side 5a in the vertical direction, thereby reducing the downward bending requirements of the lower projection when snapped. The locking surfaces 45, 65 have a larger locking angle and the lower gripping surfaces have a smaller angle. The connecting edges 4a, 4b in the locking element and the locking groove are larger for optimal insertion, and at the same time the contact surfaces between the locking surfaces are smaller because the strength requirements are smaller than on the short side. The long and short side fasteners can be composed of different materials or material properties in the upper, lower, and tongue and these features can be adjusted to contribute to optimizing the different properties required for the long and short side with respect to function and strength.

Figure 35 shows in detail how the floorboard joint system is formed on the long side. Of course, the principles described herein can be applied to both the long and short sides. Parts that have not been discussed in detail will now be described.

The locking surfaces 45, 65 have an angle HLA that is greater than the tangent of the tangent TL1. This gives greater horizontal locking strength. This large bending should be adapted to the wood core material and optimized for bending stiffness so that it can be rotated inwards and upwards. The contact surfaces of the locking surfaces should be minimized and adapted to the core properties.

When the plates are joined, small portions, preferably less than half the surface of the lock element in the vertical direction, form the contact surfaces of the lock element 8 and the lock groove 14. Most are formed by 20 rounded, beveled or bent guide portions that are not in joined position during turning inwards and upwards in contact with each other.

The inventor has discovered that very small contact surfaces in relation to the floor thickness T between the locking surfaces 45, 65, for example several tenths of a millimeter, provide very high locking strength and shear strength of the locking element in a horizontal plane, i. j. in the HP surface plane. This can be used to provide locking surfaces with an angle exceeding the tangent of TL1.

In this case, the locking surfaces 45, 65 are planar and parallel. This is advantageous in relation to the locking surface 55 of the locking groove. If the tool is moved parallel to the locking surface 45, it will not affect the vertical distance to the joint plane VP, and it will be easier to ensure high quality of the joint. But even small deviations from the plane can give equivalent results.

Similarly, the lower abutment surfaces 50, 71 may also be substantially planar with an angle VLA2, which in this case is greater than the tangent line TL2 to the point P7 located on the abutment surface 71 closest to the bottom of the tongue groove. This allows for inward rotation with play during the entire angular movement. Also, the abutment surfaces 50, 71 are relatively small in relation to the thickness of the floor T. These abutment surfaces may also be substantially planar. Plane support surfaces facilitate production according to the described principles.

The support surfaces 50, 71 may be made at an angle that is less than the inclination angle of the tangent TL2. In this case, the rotation is performed in part by some compression of the material and bending down the lower projection 40. If the bearing surfaces 50, 71 are small relative to the floor thickness T, the possibility of shaping surfaces with angles greater and smaller than the tangents TL1 and TL2 is increased. , respectively.

Figure 36 shows an upturned plate having the geometry of Figure 35 and whose locking surfaces therefore have a greater slope than tangent TL1 and whose support surfaces have less inclination than the tangent TL2 and at the same time these surfaces are relatively small. The overlap at points P4 and P7 in conjunction with inward and upward rotation will then be extremely small. The point P4 may be rotated depending on the material combination upon compression at the upper joint edges ΚΙ, K2 and at the points P4, K3, K4, while at the same time the upper projection 39 and the tongue 38 may bend in the directions B1 and B2 from the contact point P4. The lower projection may bend downward from the contact point P7 in the direction B3.

The top abutment surfaces 43, 64 are preferably perpendicular to the plane of the joint VP. Production is clearly facilitated if the upper and lower abutment surfaces are parallel planes and preferably horizontal.

Returning to Figure 35, for example, the circular arc C1 shows when the upper abutment surfaces can be formed in many different ways within this circular arc C1 without compromising the possibility of rotation and clamping. It also shows the circular arc C2 that the inner parts of the tongue groove and the outer parts of the tongue according to the above principles can be formed in many different ways without compromising the possibilities of rotation and clamping. The upper projection 39 is larger in its entire area than the lower projection 40. This is advantageous in terms of strength. In addition, this is advantageous in connection with parquet floors, which can thus be produced with a thicker hardwood surface layer.

S1-S5 shows areas where the joining surfaces on both sides cannot be in contact with each other, neither in the joined positions, but also during inward rotation. The contact between the tongue and the tongue groove in these spaces S1 - S2 contributes marginally to the improvement of the locking in the direction D1 and hardly to the improvement of the locking in the direction D2. However, the contact prevents inward rotation and lateral displacement, causes unnecessary manufacturing tolerance problems and increases the risk of rupture and undesirable effects such as backflow.

The tooling angle TA, designated TA4 in Figure 38d, forms the locking surface 44 of the undercut portion 35 and operates at the same angle as the locking surface angle, the portion of the tool that is within a vertical plane relative to the keyway having a width TT perpendicular to tool angle TA. The angle TA and the width TT partly determine the possibilities of shaping the outer portions 52 of the lower projection 40.

Many radii and angles are important for optimum manufacturing processes, function, cost and strength.

Contact area size should be minimized. This reduces friction and facilitates sliding in the locked position, turning in and out, simplifying production and reducing the risk of swelling and cracking. In a preferred example, less than 30% of the surface portion of the tongue 38 is formed by the contact surfaces with the tongue groove 36. The contact surfaces of the locking surfaces 65, 45 in this embodiment are only 2% of the floor thickness and the lower abutment surfaces have a contact surface which is only 10% of the floor thickness. As shown, the locking system in this embodiment has a plurality of S1-S5 portions that determine free surfaces without contact with each other. The space between these free surfaces and the remainder of the joint system within the scope of the invention can be filled with sealant, gasket, impregnation of various kinds, lubricating oil and the like. By free surfaces is meant here the shape of the surface in the joint system, which is obtained in connection with the machining of the necessary cutting tools.

If the fastening system abuts tightly, the locking surfaces 65, 45 prevent horizontal separation even if they have an angle HLA relative to the horizontal plane HP greater than zero. The tensile strength of the joining system increases considerably when this locking angle increases and when there is an angle difference between the locking angle HLA of the locking surfaces 65, 45 and the gripping angle VLA2 of the lower abutment surfaces 50, 71 assuming this angle is smaller. If high strength is not required, the locking surfaces can be formed with small angles and small differences in angle to the lower gripping surfaces.

For good joint quality in floating floors, the locking angle HLA and the difference in angle to the lower supporting surfaces HLA-VLA2 must generally be 20 °. Even better strength is obtained when the locking angle HLA and the difference in angle to the lower abutment surfaces HLA-VLA2 are, for example, 30 °. In the preferred treasure of Figure 35, the locking angle is 50 ° and the angle of the abutment surfaces is 20 °. As can be seen in the foregoing embodiments, the coupling system of the invention can be formed with even greater locking angles and angular differences.

A large number of tests have been carried out with different locking angles and catch angles. These tests have shown that it is possible to produce a high quality joint system with locking angles between 40 ° and 55 ° and support surface angles between 0 ° and 25 °. However, it should be added that other ratios may also have satisfactory results.

The horizontal dimension of the PA tongue should exceed 1/3 of the floor thickness, preferably around 0.5 T. As a rule, this is necessary to create a solid locking element 8 with a guide and for a suitable available material in the upper projection 39 between the locking surface 65 and the vertical plane VP .

The horizontal dimension P1 of the tongue 38 should be divided into two substantially equal parts PA1 and PA2, where PA1 should form the locking element and the greater part P2 should form the support surface 64. The horizontal dimension P1 of the locking element should not be less than 0.2 floor thickness. The upper abutment surface 64 should not be too large, especially on the long side of the floorboard. Otherwise, the friction during side shifting will be too great. To allow for rational production, the groove depth G should be 2% deeper than the overlap of the tongue PA from the joint plane VP. The smallest distance of the upper projection to the floor surface adjacent to the undercut portion 35 should be greater than the smallest distance of the lower projection between the lower abutment surface 71 and the underside of the floorboard. The TT tool width should be 0.1 floor thickness T.

Figures 37a-c show a floorboard according to the invention. In particular, this embodiment shows that the short side joint system may comprise different materials and material combinations 30b and 30c and that these may differ from the long side core joint material. For example, the short side tongue groove portion 36 may be comprised of a harder and more flexible wood material than, for example, the tongue part 38, which may be harder and stiffer and have different properties than the long side core. On the short side with the tongue groove 36, for example, a wood type 30b is selected which is more flexible than the wood type 30c on the other short side where the tongue is formed. This is particularly suitable for parquet floors with a lamella core, where the upper and lower sides are composed of different types of wood and the core forms blocks that stick together. This design offers great possibilities to create composite materials to optimize function, strength and cost.

It is also possible to alternate the materials on one side of the length. Thus, for example, blocks that are located between two short sides may be of different types of wood or materials, some of which may be selected for their beneficial and appropriate properties that improve laying, strength, etc. Different properties can also be obtained by different fiber orientation on the long and short sides, and also plastic materials can be used on the short side and, for example, on different parts of the long side. If the floorboard or parts of its core consist, for example, of plywood with several layers, these layers can be selected such that the upper projection, tongue and lower projection on the long side and short side can have all parts of different materials, with different fiber orientations, etc. , which can provide various properties in terms of strength, flexibility, machinability and the like.

Figures 38a-d show production methods according to the present invention. In the embodiment shown, manufacturing the joint edge and tongue groove has four steps. The tools used have a diameter that exceeds the floor thickness. The tools are used to form an undercut groove at a large locking angle in a tongue groove with a lower projection that extends to the other side of the undercut groove.

For ease of understanding and comparison with the previously described joint systems, the joint edges are drawn up with the floor surface. Usually, however, the sheets are turned downside during processing.

The first TP1 tool is a contour milling cutter that operates at an angle of TA1 to the horizontal plane. The second TP2 tool can operate horizontally to form upper and lower abutment surfaces. The third tool TA3 can operate substantially vertically, but also at an angle, and forms the upper connecting edge.

The decisive tool is the TP4 tool which forms the outer part of the cam groove and its cam surface. TA4 corresponds to the TA of Figure 35. As can be seen from Figure 38d, this tool removes only a minimal amount of material and forms a substantially large angle locking surface. To prevent the tools from breaking, they must be shaped with a wide section that extends beyond the outer vertical plane. However, the amount of material removed must be kept to a minimum to avoid unnecessary wear and tear on the tool. This is achieved by a suitable angle and design of the TP1 contour milling machine.

This manufacturing method is characterized in particular in that it requires at least two different angles to form the undercut portion 35 of the keyway groove in the upper part of the keyway groove 36. The keyway groove may be formed by other tools which are used in different order.

The description is now focused on details in a method of forming a tongue groove 36 in a floorboard having an upper side 2 in the surface plane HP and a connecting edge 4a with a plane of the joint VP perpendicular to the upper side. The tongue groove extends from the plane of the connecting edge 4a and is defined by two projections 39 and 40, each having a free outer end. The tongue groove has at least one of them an undercut 35 having a locking surface 45 which is located further from the plane of the joint VP, such as the free outer end 52 of the second projection. According to the method, it is machined using several rotary cutting tools with a larger diameter than the thickness T of the floorboard. In the method, the cutting tools and the floorboard are designed to perform relative movement to each other and parallel to the joining edge of the floorboard. Characteristic of the method is (1) that the undercut is formed by at least two such cutting tools having their rotating shaft inclined at different angles to the top side 2 of the floorboard; (2) that the first of these tools is directed to form a portion of the undercut farther from the joint plane VP than the locking surface 45 of the scheduled undercut; (3) that the other of these tools is intended to provide a locking surface 45 of the undercut. The first of these tools is designed by its rotary shaft to create a greater angle to the front side 2 of the floorboard than the latter. The lower projection 40 is shaped to extend beyond the plane of the joint VP. The lower projection 40 may also be shaped so as to reach the plane of the joint. Alternatively, the lower projection 40 may be shaped such that its end is further from the plane of the joint VP.

The first of the tools according to the embodiment may be determined by its rotary shaft to create an angle of at most 85 ° to the surface plane HP. The other of the tools may be directed according to the embodiment with its rotary shaft to create an angle of at most 60 ° to the surface plane HP. In addition, floorboard tools may be aligned according to the angle of their rotary shaft to the HP surface plane, so that tools with a larger rotary shaft angle are designed to machine the floorboard in front of tools with a smaller rotary shaft angle.

Further, a third of the tools may be guided to form the lower portions of the tongue groove 36. This third tool may be in contact with the floorboard between said first and said second tools. The third tool can be designed with its rotary shaft to create an angle of nearly 90 ° to the HP surface plane. Further, the first of the tools may be designed to machine a wider portion of the surface of the joining edge 4a of the floorboard than the second of the tools. The second tool may be shaped such that its surface towards the HP surface plane is profiled by reducing the thickness of the tool from a view parallel to the rotary shaft, without the radial outer portions of the tool. In addition, at least three of the tools can be guided by varying their rotary shafts to form undercut portions of the tongue groove. The tools are used for machining floorboards made of wood or chipboard.

Fig. 39 shows a coupling system that is capable of compensating for backwater. Since the relative humidity increases as the cold and warm weather changes, the surface front side 32 of the layer is swollen and tension is created at the connecting edges 4a and 4b. If the joint is not resilient, the edges 41 and 61 of the joint edges may crush or the locking element 8 may break. This problem may be solved by a joint system that is designed to achieve the following characteristics which, alone or in combination, reduce the problem. .

The joint system may be formed such that the floorboards have little play when the joint edges are pressed horizontally together, for example during manufacture and at normal relative humidity. The will of a few hundredths of a millimeter supports the reduction of the problem. Negative will, i. j. Initial voltage can cause the opposite effect.

If the contact surface between the locking surfaces 45, 65 is small, the joint system can be formed so that it is much easier to compress than the surfaces 41, 61 of the upper joint edges. The locking element 8 may be formed with a groove 64a between the locking surface and the upper horizontal abutment surface 64. By a suitable design of the tongue 38 and the locking element 8, the outer tongue part 69 may bend outwardly towards the inner tongue groove 48 and act as a resilient member and shrinking the surface layers.

In this embodiment, the lower abutment surfaces of the coupling system are shaped parallel to the horizontal plane for maximum vertical locking. It is also possible to obtain extensibility by using compressible materials, for example, between two locking surfaces 45, 65 or by selecting compressible materials to produce a tongue or tongue groove.

Figure 40 shows a coupling system according to the invention that is optimized for high stiffness in the tongue 38. In this case, the outer tongue part is in contact with the inner tongue groove part. If the contact surface is small and if the contact occurs without too much compression, the coupling system may be moved in the locked position.

Fig. 41 shows a joint system wherein the lower abutment surfaces 50, 71 have two angles. A portion of the support surfaces outside the joint plane is parallel to the horizontal plane. Within the joint plane closest to the inner part of the tongue groove, the planes have an angle corresponding to the tangent of the circular arc C2, which is tangent to the innermost edge of the interconnected portions of the abutment surface. The locking surfaces have relatively small locking angles. The strength may still be sufficient because the lower projection 40 can be made hard and rigid, and because the difference between the angles on the parallel portion of the lower abutment surfaces 50, 71 is large. In this embodiment, the locking surfaces 45, 65 also serve as upper abutment surfaces. The joining system does not have additional upper abutment surfaces in addition to the locking surfaces which prevent vertical separation.

Figures 42a and 42b show a coupling system that is suitable for locking short sides and which can have high tensile strength even on softer materials, since the locking element 8 has a large horizontal shear damping surface. The tongue 38 has a lower part which is on the outside of the circular arc C2 and which thus does not participate in the described basic principle of inward rotation. As can be seen from Figure 42b, the coupling system can still be released by pivoting upwardly around the upper coupling edge, since the locking member 8 of the tongue 38 after the first pivoting upward operation can be disengaged from the tongue groove by horizontal withdrawal. The previously described principles for inward rotation and upward rotation around the upper joining edges should therefore allow upward rotation until the joined system is released in another way, for example by pulling or combining the release of the pinch when bending the lower projection 40.

Figures 43a-c show the basic principles of shaping the lower tongue in relation to the lower projection 40 and to facilitate horizontal engagement according to the invention in a locking groove connection system in the rigid upper projection 39 and the resilient lower projection 40. In this embodiment, the upper projection 39 is significantly stiffer , inter alia due to the fact that it may be stronger or may be composed of harder or stiffer materials. The lower protrusion 40 may be weakened and softer and bending is not important when engaged. The snap will be greatly facilitated by the maximum bending of the lower projection 40 against the maximum limit B1, which is characterized in that when the tongue 38 is inserted as far as possible into the tongue groove 36, the rounded guide parts come into contact with each other. If the tongue 38 is inserted even further, the lower projection 40 is bent back until the engagement is complete and the lock element 8 is fully inserted into the final position in the lock groove. The lower and front portions 49 of the tongue 38 should be designed so as not to bend down the lower projection 40, which should be downwardly compressed by the lower abutment surface 50. This tongue portion 49 should have a shape that either touches or freely passes at a maximum the bent level of the lower projection 40, when the lower projection 40 is bent over the rounded outer portion of the lower gripping surface 50 of the tongue 38. If the tongue 38 has a shape that interferes with the lower projection 40 in this position, The B2 of Figure 43b may be significantly larger. This can cause a high friction in connection with the engagement and the risk that the joint will be damaged. Figure 43b shows that the maximum bend may be limited by the tongue groove 36 and tongue 38, which are designed such that there is a gap S4 between the lower and outer tongue portions 49 and the lower projection 40.

Horizontal engagement is typically used when joining the short side after locking the long side. In the case of a long side engagement, it is also possible to perform the engagement according to the invention with a single plate in a low upward slope. This upwardly twisted clamping position is shown in Figure 44. The lock member guide 66 requires only a small bend B3 of the lower projection 40 to come into contact with the lock groove guide portion 44 so that the lock member can then be inserted downwardly into the undercut portion 35 of the cam groove.

Figures 45-50 show various variants of the invention that can be used on the long or short side and which can be produced using large rotary cutting tools. With modern production technology it is possible to create complex shapes by machining plate materials at low cost. It should be emphasized that most of the geometries shown in these and earlier preferred assemblies may of course be formed by extrusion, but this method is usually significantly more expensive than machining and is not suitable for shaping most board materials that are commonly used for floors.

Figures 45a and 45b illustrate a locking system according to the invention wherein the outer portion of the tongue 38 is formed to be bendable. This bending ability is obtained by bifurcating the tongue top. When engagement occurs, the lower projection 40 is bent down and the outer lower portion of the tongue 38 is bent up.

Figures 46a and 46b illustrate a lock system according to the invention with a bifurcated tongue. During engagement, the two portions of the tongue bend together, while the two projections bend apart.

The two connection systems are such that they allow rotation in and out when locked and dismounted.

Figures 47a and 47b show a combined connection where the separate piece 40b forms an overlapping portion of the lower projection and the piece may be resilient and resilient. The coupling system is capable of turning. The lower projection, which forms part of the core, is shaped with its own support surface in such a way that the engagement takes place without the projection having to be bent. Only the protruding individual part, which can be made of aluminum sheet, is flexible. The coupling system can also be designed such that both parts of the projection are resilient.

Figures 48a and 48b show the snap-fit of a combination joint with a lower projection having two portions where only a separate projection forms a support surface. This coupling system can be used, for example, on the short side together with some other coupling system according to the invention. An advantage of this coupling system is that, for example, the cam groove 35 can be formed rationally with a large degree of freedom and large cutting tools can be used. After machining, the outer projection 40b is attached and its shape will not affect the machining possibilities. The outer protrusion 40b is resilient and has no locking element in this embodiment. Another advantage is that the joining system allows the joining of extremely thin core materials, since the lower projection can be made very thin. For example, the core material may be a thin compact laminate, and the top and bottom layers may be relatively coarse layers, for example, of cork or a soft plastic material, which may form a soft and sound absorbing floor. Using this technology, it is possible to combine core materials having a thickness of about 2 mm compared to normal core materials, which are usually not thinner 7 mm. The saving of thickness can be used to increase the thickness of other layers. However, it is clear that this kind of joint can also use thicker materials.

Figures 49a and 50 show two variants of combination joints that can be used, for example, on the short side in combination with other preferred systems. The combination joint of Figure 49 may be in an embodiment where the tape forms an overlapping spring portion of the tongue and the system will then perform a function similar to Figure 45. Figure 50 shows that the combination joint may be formed by a locking element 8b at the outer lower projection 40b which is located within the joint plane.

Figures 51a-f illustrate a laying method that can be used to join floorboards in combination with horizontal zoom, up-turn, snap-in in the up-lifted position, and fold down. This laying method can be used for the floorboards according to the invention, but can also be used for optimal mechanical floor fastening systems having properties that the laying method can be applied. To simplify the description, the laying method will be shown on one plate, called a grooved plate, which will be joined to a second plate, called a tongue plate. The boards are practically the same. It will be appreciated that the entire laying procedure can also be performed from the tongue side, which is connected in the same way to the groove side.

The tongue plate with the tongue 38 and the tongue plate 4b with the tongue groove 36 lie in the initial position on the flooring of Fig. 51a. The tongue 38 and tongue groove 36 have lock elements which allow vertical and horizontal separation. Gradually, the groove plate is moved horizontally in the direction F1 relative to the tongue plate until the tongue 38 is in contact with the tongue groove 36 and until the upper and lower portions of the tongue are partially inserted into the tongue groove of Figure 51b. This first operation forces the joint portions of the plates to assume a relatively equal vertical position over the entire length of the plate and all arc-shaped differences have been aligned.

If it moves the groove plate against the tongue plate, the connecting edges of the groove plate will slightly lift. The groove plate is then rotated upward by moving S1 at an angle while being held in contact with the tongue plate or alternatively pressed in the direction F1 relative to the tongue plate of Figure 51c. When the groove plate reaches an angle SA to the floor base corresponding to the upwardly rotated clamped position as described and as shown in Figure 44, the groove plate will move relative to the tongue plate so that the surfaces 4i, 61 of the upper joining edges get into each other contact so that the tongue locking elements are partially inserted into the tongue groove locking elements.

This clamping function in the upturned position is characterized in that the outer parts of the tongue groove widen and spring back. The extension is substantially smaller than required when engaged in a horizontal position. The clamping angle SA depends on the pressure at which the plates are pressed together when the groove plate is turned upwards. If the pressure in the direction F1 is large, the plates are clamped at a smaller angle SA than at a lower pressure. The gripping position is therefore characterized in that the guide parts of the locking elements are in contact with each other so that they can form a grip. If the boards have a banana shape, they are aligned and locked when clamped. The groove plate can now combine the angular movement S2 with the pressure against the joint edge by rotating downwards according to Figure 5e and locked against the tongue plate in the final position. This is shown in Figure 51 f. Depending on the design of the joint, it is possible to determine with great precision the clamping angle SA, which is the best parameter with regard to the requirement that the clamping must be effected with a reasonably high force and that the lock guiding parts should have such engagement that they keep any banana shapes connected the final grip will be made without the risk of the joint being damaged.

The floorboards can be laid without any preparations. In some cases, the installation will be facilitated by the use of suitable formulations of Figures 52a and 52b. A preferred jig will be a punching or pressing block 80, which is designed to have a front and bottom portions 81 that rotate the groove plate upward when inserted below the edge of the floorboard. It has an upper abutment edge 82, which in contact with the edge portion of the groove plate is in the upside-down position. When the impact block 80 is to be inserted under the groove plate so that the abutment edge 82 is in contact with the floorboard, the groove plate will have a predetermined clamping angle. The tongue groove of the groove plate can now be firmly connected to the tongue tongue of the tongue plate by pressing or striking against the impact block. The impact block can of course also be used on other parts of the board. Obviously, this is done in combination by pressing against other parts of the board, by the possibility of doubling the impact block or some other jig that provides a similar result when, for example, one jig rotates the jaw to the clamping angle and the other jig is used for pressing. The same method is used to turn up the groove side of the new board and connect it to the side with the tongue of the previously laid board.

Various aspects of the floorboard laying tool will now be illustrated to illustrate. Such a sheet laying tool by connecting the tongue and tongue groove to each other can be designed as a block 80 with a gripping surface 82 for engaging the joining edge 4a, 4b of the floorboard. The tool may be shaped as a wedge for insertion under the floorboard and have its gripping surface 82 positioned closer to the thin end of the wedge. The gripping surface 82 of the tool may be concave curved to at least partially grip the joining edges 4a, 4b of the floorboard. In addition, the wedge angle S 1 and the position of the gripping surface 82 on the thin side of the wedge can be adjusted to a predetermined lifting angle of the floorboard that is raised by the wedge 80. The joining edges of the floorboard contact the gripping surface 82. The contact surface 82 of the wedge 80 may be shaped to touch the joining edge 4b having the tongue 38 facing obliquely upwards to connect the undercut tongue 36 formed on the opposite joining edge 4a of the floorboard with the tongue 38 previously laid floorboard. Alternatively, the wedge contact surface 82 may be shaped to contact with a joint edge 4a having an undercut tongue 36 to connect the tongue 38 extending obliquely upwardly and formed at the opposite joint edge 4b of the floorboard.

The tool described herein is used for mechanically joining floorboards by lifting one floorboard against another and joining and locking the mechanical floorboard systems. The tool may also be used to mechanically connect such floorboards to other such floorboards by clamping the mechanical locking systems of the floorboards together when the board is in the raised position. Further, the tool may be used such that the wedge gripping surface 82 is made to protect against the joining edge 4b having a tongue 38 angled upwardly to connect the undercut groove 36 formed at the opposite joining edge 4a of the floorboard to the tongue 38 of the previously laid floorboard. Alternatively, the tool may be used such that the wedge gripping surface 82 is made to protect against the joining edge 4a having an undercut groove 36 extending obliquely upwardly to join the tongue 38 formed at the opposite joining edge 4b of the floorboard with the undercut groove 36 of the previously laid floorboard. .

Fig. 53 shows how two plates 2a and 2b, after being joined to an adjacent plate along the edge of the long side, can be moved in a locked position in the direction F2 so that the other two sides are joined together by a horizontal horizontal clamping.

The locking in the upward position can be carried out on both the long and short sides. If the short side of one plate is first attached, its long side may also be clamped in an obliquely upward position so as to assume its clamping angle. This then engages in an obliquely upward position and at the same time relocates in a locked position along the short side. Upon engagement, the board folds down and is locked on both sides, long and short.

Figures 53 and 54 illustrate a problem that occurs in connection with the engagement of two short sides of two boards 2a and 2b that have already been connected to their long sides with another first board 1. When the floorboard 2a is clamped into the floorboard 2b, the inner corner portions 91 and 92 closest to the long side of the first plate 1 are located on the same plane. This is due to the fact that the boards 2a and 2b are connected with their long sides to the same floorboard 1. According to Fig. 54b, showing section C3-C4, the tongue 38 cannot be inserted into the tongue groove 36 to start bending down the lower projection 40. In the outer corner portions 93, 94 on the other long side in section C1-C2 shown in Figure 54a, the tongue 38 may be inserted into the tongue groove to begin bending down the lower projection 40 with the plate 2b which automatically extends upwards correspondingly in height lock element 8.

It has been found that there may be problems with the engagement of the inner corner portions in lateral displacement in the same plane, and that these problems may cause a high resistance to engagement and a risk of rupture of the coupling system. The problem can be solved by suitable joint design and material selection that allow material deformation by bending many connecting parts.

When engagement occurs in such a specially designed coupling system, the following is performed. In the lateral displacement, the outer tongue guide portions 42, 68 cooperate and the upper lip pushes the tongue lock element 8 below the outer part of the upper lip 39. The tongue bends down and the upper lip bends up (indicated by the arrows in Figure 54b). The corner portion 92 in Figure 53 is pushed upward by the lower projection 40 on the long side of the plate 2b that bends and the corner portion 91 is compressed down by the upper projection on the long side of the plate 2a that bends upwards. The coupling system should be designed such that the sum of these four deformations is so large that the locking member can slide along the upper projection and fit into the locking groove. It is known that this could be the case with the tongue groove 36, which would widen in connection with the engagement. However, it is not known that a pen that would normally be rigid and constructed so that it can be bent in connection with the engagement could be advantageous. Such an embodiment is shown in Figure 55. The groove or equivalent 63 may be formed in the upper and lower parts of the tongue within the vertical plane VP. The entire length PB of the tongue from its inner part against its outer part may be extended and may, for example, be greater than half the thickness of the floor T.

Figures 56 and 57 illustrate how portions of the joining system are bent by engagement on the inner corner portion 91, 92 in Figure 57 and the outer corner portions 93, 94 in Figure 56 of two floorboards 2a and 2b. Therefore, only a thin projection and bending of the tongue is required to simplify production. Of course, all parts subjected to pressure will be compressed and bent to varying degrees depending on thickness, flexibility, material composition and the like.

Figures 56a and 57a show the position where the edges of the plates come into contact with each other. The coupling system is designed in such a way that even in this position the farthest tip of the tongue 38 will not be located inside the outer portion of the lower projection 40. When the plates further slide against each other, the tongue 38 in the inner corner 91. 92 will push the plate 2b upwards as shown 56b, 57b. The tongue is bent down and the plate 2b is rotated upwards at the outer corner 93, 94. Figure 57c shows that the tongue 38 will be bent down in the inner corner 9i, 92. At the outer corner 93, 94 of Figure 56c, the tongue 38 is bent up and the lower projection 40 is bent down. Referring to Figs. 56d, 57d, this bending continues as the plates continue to move relative to each other, and now the lower projection in the inner corner 91, 92 of Fig. 57d is also bent. Figures 56e, 57e show the position of the engagement. The engagement may be significantly facilitated if the tongue 38 is flexible and if the outer portion of the tongue 38 is located within the outer portion of the lower projection 40 when the tongue and the groove come into contact with each other as plates that are located in the same plane when engaged by the engagement that This is done after the floorboards have locked on their other two sides.

The scope of the invention may be several variants where different parts of the joint system have different width, length, thickness, angles and radii, different board materials, homogeneous plastics and wood panels. All fasteners were tested in the up and down pivot positions, clamping and rotating the spline and tongue relative to each other, and various combinations of the systems described herein, as well as the known long and short side systems. The locking system has been made such that the locking surfaces are also the upper abutment surfaces when the tongue and groove had many locking elements and where also the lower projection and the upper part of the tongue were formed by horizontal locking means in the form of the locking element and the locking groove.

Industrial usability

The invention is particularly intended for floating floors, i. j. for floors that can move against the foundation. It can be used for all kinds of hard floors, such as wood flooring, laminated or chipboard core wood, veneered and wood fiber core, laminate flooring, plastic core flooring and the like. Obviously, the invention can be applied to other types of floorboards which are machined with cutting tools, such as plywood flooring or particle board. Even in cases where installation is not considered after joining the floorboards to the foundation.

Claims (63)

A flooring system comprising floorboards (1, 1 ') mechanically joined in a joint plane (VP), said floorboards having a core (30), a front side (2, 32), a rear side (34) and opposing connecting edges (4a) 4b), one of which (4a) is shaped as a tongue groove (36), which is defined by the upper and lower projections (39, 40) and has a lower end (48) and the other connecting edge (4b) is shaped as a tongue ( 38) with an upwardly directed portion (8), the tongue groove (36), seen from the plane of the joint (VP), has the shape of an undercut groove with an opening, an inner undercut portion (35) and an inner locking surface (45) (40) are formed integrally with the floorboard core (30) and the tongue (38) has a floor locking surface (65) that is shaped to cooperate with the inner floor locking surface (45) in the tongue groove (36) of the adjacent floorboard when such two floorboards (1, 1 ') are mechanically connected for positioning their connecting edges (4a, 4b) in the same surface plane (HP) and meet at a plane of the joint (VP) perpendicular thereto, characterized in that at least a major part of the lower end (48) of the tongue groove (36) parallel to the surface plane (HP), it is located further from the joint plane (VP) than the outer end (69) of the tongue (38), the inner floor lock surface (45) of the tongue groove (36) being formed on the upper projection (39) ) with a tongue groove undercut portion (35) for cooperating with a corresponding floor locking surface (65) of the tongue (38), wherein the floor surface is formed with the upwardly facing portion (8) of the tongue (38) jointly preventing the two mechanically connected plates from (D2) perpendicular to the plane of the joint (VP), wherein the lower projection (40) has a support surface (50) to cooperate with a corresponding support surface (71) of the tongue (38) further from the lower end (48) of the undercut groove. moving the two mechanically connected floorboards in the direction (D1) perpendicular to the surface plane (HP), and all the parts of the lower projection (40) that are connected to the core, seen from point (C) where the surface plane (HP) intersects and the joint plane (VP) are located outside the plane (LP2), which is located further from said point than the locking plane (LP1), which is parallel to it and tangent to the cooperating tongue groove surfaces (45, 65). 36) and tongues (38), when said locking surfaces are most inclined against the surface plane (HP), wherein the upper projection (39) and the lower projection (40) and the tongue (38) of the connecting edges (4a, 4b) are designed to disengage two mechanically bonded floorboards by rotating one floorboard against the other upwards around the pivot center (C) just at the intersection point between the surface plane (HP) and the joint plane (VP) to disconnect the floorboard tongue (38) and the tongue grooves (36) of another floorboard (1). Floor system according to claim 1, characterized in that it comprises an upper projection (39), a lower projection (40) and a tongue (38) of the connecting edges (4a, 4b) for connecting two floorboards (1,1 ') once a floorboard, when the two floorboards are in contact with each other, rotating one with respect to the other downward about the pivot center (C) just at the intersection point between the surface plane (HP) and the joint plane (VP) to connect the floorboard tongue to the tongue groove of another floorboard. A flooring system according to claim 1 or 2, characterized in that it comprises an undercut tongue groove (36) and a tongue (38) for displacing the floorboard (1, 1 ') mechanically connected to a similar board in the direction (D3) along joint plane (VP). A flooring system according to claim 1, 2 or 3, characterized in that it comprises an undercut tongue groove (36) and tongue (38) for connecting and disconnecting one plate from the other plate by rotating one plate relative to the other in contact with each other between the boards at point (C) at the joint edges just adjacent the intersection between the surface plane (HP) and the plane of the joint (VP). A flooring system according to any one of the preceding claims, characterized in that it comprises an undercut tongue groove (36) and tongue (38) for joining and uncoupling the plates by rotating one plate against the other in contact between the plates at a point on the joint edges of the plates the intersection between the surface plane (HP) and the plane of the joint (VP) without substantial contact between the side of the tongue (38) facing away from the surface plane (HP) and the lower projection. Floor system according to one of Claims 1 to 4, characterized in that they comprise an undercut groove (36) and a tongue (38) for connecting and disconnecting the plates (1, 1 ') by rotating one plate against the other in contact with each other between at the joining edges of the plates just adjacent the intersection between the surface plane (HP) and the joint plane (VP) and in direct contact between the tongue sides (38) towards the surface plane (HP) and away from the surface plane (HP) and the upper projection (39); a lower projection (40), respectively. Floor system according to any one of the preceding claims, characterized in that the distance between the floor plane (LP2) and the plane (LP1) which are parallel and from the outside are located all the parts of the lower projection (40) which are connected to the core. (30) is at least 10% of the floorboard thickness (T). Floor system according to any one of the preceding claims, characterized in that the floor locking surfaces (45, 65) of the upper projection (39) and the tongues (38) form an angle of less than 90 ° but at least 20 ° with the surface plane (HP). . Floor system according to claim 8, characterized in that the floor surfaces (45, 65) of the upper projection (39) and the tongue (38) form an angle with the surface plane (HP) of at least 30 °. Floor system according to any one of the preceding claims, characterized in that it comprises an undercut tongue (36) and tongue (38), the outer end (69) of the tongue (38) being spaced from the undercut groove (36) all the way. a length from the floor surfaces (45, 65) touching each other, the upper projection (39) and the tongue (38) to the cooperating support surfaces (50, 71) of the lower projection (40) and the tongue (38). A flooring system according to claim 10, characterized in that any contact portion between the outer end (69) of the tongue (38) and the undercut groove (36) has a smaller area in the vertical plane than the floor surfaces (45, 65) when mechanically joined. of the two plates (1, 1 '). Floor system according to any one of the preceding claims, characterized in that it comprises connecting edges (4a, 4b) with their tongue (38) and tongue groove (36) for contact of surfaces between the connecting edges (4a, 4b) at most 30% of the surface the edges of the tongue supporting edge portion (4b) measured from the top side of the floorboard to the bottom side thereof when the two floorboards are joined. Floor system according to any one of the preceding claims, characterized in that the cooperating support surfaces (50, 71) of the tongue (38) and the lower projection (40) are parallel to or opposed to the surface plane (HP). equal to or smaller than the tangent of a circular arc that touches the abutment surfaces supporting each other at a point closest to the lower end (48) of the undercut groove and which has a center at the point (C) where the surface plane (HP) and the joint plane intersect; which is visible on the cut board. Floor system according to claim 13, characterized in that the cooperating support surfaces (50, 71) of the tongue (38) and the lower projection (40) are at an angle of 0 ° to 30 ° relative to the surface plane (HP). Floor system according to claim 14, characterized in that the cooperating support surfaces (50, 71) of the tongue (38) and the lower projection (40) are at an angle of at least 10 ° relative to the surface plane (HP). Floor system according to claim 14 or 15, characterized in that the cooperating support surfaces (50, 71) of the tongue (38) and the lower projection (40) are at an angle of at most 20 ° to the surface plane (HP). Floor system according to claim 13, characterized in that the cooperating support surfaces (50, 71) of the tongue (38) and the lower projection (40) are substantially at the same angle to the surface plane (HP) as the tangent to the circular arc. it touches the abutment surfaces (50, 71) and has its center at the point where the surface plane (HP) and the joint plane (VP) intersected by the plate intersect. Floor system according to claim 13, characterized in that the cooperating support surfaces (50, 71) of the tongue (38) and the lower projection (40) are at a greater angle to the surface plane (HP) than the tangent to the circular arc that touches the supporting surfaces supporting each other at a point closest to the lower portion of the undercut groove and has a center at the point where the surface plane (HP) and the joint plane (VP) intersect. Floor system according to one of the preceding claims, characterized in that the cooperating support surfaces (50, 71) of the tongue (38) and the lower projection (40) are at a lower angle to the surface plane (HP) than the cooperating locking surfaces of the upper the projection (39) and the tongue (38). Floor system according to claim 19, characterized in that the cooperating abutment surfaces of the tongue (38) and the lower projection (40) are inclined in the same direction but at a smaller angle to the surface plane (HP) than the cooperating floor surfaces (45, 65). ) of the upper projection (39) and the tongue (38). Floor system according to one of Claims 13 to 20, characterized in that the support surfaces (50, 71) form an angle at least 20 ° greater than the surface plane (HP) than the floor surfaces (45, 65). A flooring system according to any one of the preceding claims, characterized in that a portion of the floor surface (45) of the upper projection (39) is located closer to the lower tongue groove (48) than a portion of the abutment surfaces (50, 71). Floor system according to one of the preceding claims, characterized in that the floor surfaces (45, 65) of the upper projection (39) and the tongue (38) are substantially planar with at least parts of the surface which are intended to cooperate with each other when such two boards joined together. A flooring system according to claim 23, characterized in that the tongue (38) has a guide surface which is located outside the locking surface of the tongue (38), on the side of the joint plane (VP) and which has a smaller angle to the surface plane than has this floor surface. Floor system according to any one of the preceding claims, characterized in that the upper projection (39) has a guide surface (42) which is located closer to the opening of the tongue groove (36) than the floor surface (45) of the upper projection and has a smaller angle to the surface plane (HP) than the locking surface (45) of the upper projection. Floor system according to any one of the preceding claims, characterized in that the lower projection (40) extends to or preferably ends distant from the plane of the joint (VP). Floor system according to any one of the preceding claims, characterized in that the lower projection (40) is shorter than the upper projection (39) and terminates further from the joint plane (VP), wherein at least a portion of the abutment surfaces (50, 71) of the lower projection. (40) and tongues (38) are located at a greater distance from the joint plane (VP) than the inclined floor surfaces (45, 65) of the upper projection (39) and tongue (38). Floor system according to any one of the preceding claims, characterized in that the floor surface (65) of the tongue (38) is located at least 0.1 of the thickness (T) of the plate (1, 1 ') from the tongue top (69). 38). Floor system according to any one of the preceding claims, characterized in that the vertical surface of the cooperating locking surfaces (45, 65) is less than half the vertical surface of the undercut portion (35) viewed from the joint plane (VP) and parallel to the surface plane ( HP). A flooring system according to any one of the preceding claims, characterized in that the floor surfaces (45, 65), viewed from a vertical section through the floorboard, have an area which is at most 10% of the floorboard thickness (T). A flooring system according to any one of the preceding claims, characterized in that the length of the tongue (38) when viewed perpendicularly from the plane of the joint (VP) is at least 0.3 of the floorboard thickness (T). Floor system according to any one of the preceding claims, characterized in that the tongue-supporting joint edge (4b) and / or the tongue-like joint edge (4a) has / have a recess (63) which is located above the tongue and ends at a distance from the surface plane (HP). Floor system according to one of the preceding claims, characterized in that the upper projection (39) and the tongue (38) have abutment surfaces (43, 64) for cooperation in a locked state and which are located in the region between the plane of the joint (VP). ) and tongue locking surfaces (45, 65) and upper lip (39) cooperating with each other in the locked state. A flooring system according to claim 33, characterized in that the contact abutment surfaces (43, 64) are substantially planar. Floor system according to claims 33 or 34, characterized in that the contact abutment surfaces (43, 64) are inclined upwardly in relation to the plane of the joint (VP) against the surface plane (HP). Floor system according to claims 33 or 34, characterized in that the contact abutment surfaces (43, 64) are substantially parallel to the surface plane (HP). Floor system according to any one of the preceding claims, characterized in that the lower projection (40) of the tongue groove (36) is resilient. Floor system according to one of the preceding claims, characterized in that it is designed as a clamping device, openable by rotating one plate (1 ') against the other (1) upwards. The flooring system according to any one of the preceding claims, characterized in that it is designed to connect a previously laid floorboard to a new floorboard by pressing substantially parallel to the surface plane (HP) of the previously laid floorboard to clamp parts of the flooring system together. Floor system according to any one of the preceding claims, characterized in that the undercut tongue (36), when viewed in cross-section, has an outer open portion which is tapered inwardly. A flooring system according to claim 40, characterized in that the upper projection (39) has a chamfer (42) at its outer edge furthest from the surface plane (HP). Floor system according to one of the preceding claims, characterized in that the tongue (38), when viewed in section, has a peak (69) which is tapered at the end. Floor system according to any one of the preceding claims, characterized in that the tongue (38), when viewed in cross section, has a split apex with an upper (38a) and a lower (38b) portion of the tongue. Floor system according to one of the preceding claims, characterized in that the upper (38a) and lower (38b) parts of the tongue are made of different materials having different material properties. Floor system according to one of the preceding claims, characterized in that the tongue groove (36) and tongue (38) are formed simultaneously with the floorboard (1, 1 ') Floor system according to any one of the preceding claims, characterized in that the locking abutment surfaces (45, 65) have a greater angle to the surface plane (HP) than the tangent to the circular arc that touches the locking surfaces (45, 65) which they bond to each other at a point closest to the lower portion (48) of the undercut groove and which has its center at the point where the surface plane (HP) intersects with the plane of the joint (VP). Floor system according to any one of the preceding claims, characterized in that the upper projection (39) is thicker than the lower projection (40). A flooring system according to any one of the preceding claims, characterized in that the minimum thickness of the upper projection (39) adjacent to the undercut (35) is greater than the maximum thickness of the lower projection (40) at the abutment surface (50). Floor system according to any one of the preceding claims, characterized in that the surface of the abutment surfaces (50, 71) is at most 15% of the thickness (T) of the floorboard. Floor system according to any one of the preceding claims, characterized in that the vertical surface of the tongue groove (36) between the upper projection (39) and the lower projection (40), measured parallel to the plane of the joint (VP) and at the outer end of the support surface (36). 43), is at least 30% of the floorboard thickness (T). Floor system according to one of the preceding claims, characterized in that the depth of the tongue groove (36) measured from the joint plane (VP) is at least 2% greater than the corresponding dimension s and s and s and s and th m, that th m, that th m, that th m, that pens (38). Floor system according to any one of the preceding claims, characterized by a tongue (38) having different material properties than the upper projection (39) and the lower projection (40). Floor system according to any one of the preceding claims, characterized by the upper projection (39) being stiffer than the lower projection (40). Floor system according to any one of the preceding claims, characterized in that the upper projection (39) and the lower projection (40) are made of materials of different properties. Floor system according to any one of the preceding claims, further comprising a second mechanical lock comprising a floor groove (14) which is formed on the underside of the tongue (38) supporting edge (4b) and is parallel to the plane of the joint (14). VP) and a floor tape (6) which is attached to the joint edge (4a) of the plate below the tongue groove (36) and extends substantially along the entire length of the joint edge and has a floor element extending therefrom for release in the floor groove (14) adjacent boards when mechanically connected two such boards. Floor system according to claim 55, characterized in that the floor tape (6) extends beyond the joint plane. 57. A flooring system as claimed in any one of the preceding claims, characterized in that it is formed in a board having a core of fibreboard. A flooring system according to any one of the preceding claims, characterized in that it is formed in a board having a wood core. Floor system according to any one of the preceding claims, characterized in that the floorboards are quadrangular and have sides that are pairwise parallel. 60. The floor system of claim 59, wherein the floorboards have mechanical locking systems at all four side edges thereof. 61. The flooring system of claim 60, wherein the floorboards have mechanical clamping systems on two opposite side edges. Floor system according to claim 51, characterized in that the floorboards on the two opposite short sides of the board have an undercut groove (36) and a tongue (38) formed to be clamped together. Floor board for making a flooring system according to the preceding claims 1 to 62, by mechanically joining the board with identical floorboards (1,1 ') in the plane of the joint (VP), said floorboards having a core (30), a front side (2, 32) ), a rear side (34) and opposing connecting edges (4a, 4b), one of which (4a) is shaped as a tongue groove (36), which is defined by an upper and a lower projection (39, 40) and has a lower end (48). ) and the second connecting edge (4b) is shaped as a tongue (38) with an upwardly directed portion (8), the tongue groove (36), seen from the plane of the joint (VP), has the shape of an undercut groove (36) with an opening; (35) and the inner locking surface (45) and at least portions of the lower projection (40) integrally formed with the floorboard core (30) and the tongue (38) having a floor locking surface (65) that is formed to cooperate with the inner floor surface ( 45) in a tongue groove (36) of an adjacent floorboard when t any two floorboards (1, 1 ') are mechanically connected so that their front sides (4a, 4b) are located in the same surface plane (HP) and meet on a plane of joint (VP) perpendicular to it, indicating characterized in that at least a greater part of the lower end (48) of the tongue groove (36) viewed parallel to the surface plane (HP) is located farther from the joint plane (VP) than the outer end (69) of the tongue (38); (45) the tongue groove (36) is formed on the upper projection (39) with the undercut tongue groove part (35) to cooperate with a corresponding floor surface (65) of the tongue (38), wherein the floor surface is formed with the upwardly facing part (8) tongues (38) for jointly preventing the separation of two mechanically coupled plates in a direction (D2) perpendicular to the plane of the joint (VP), the lower projection (40) having a support surface (50) to cooperate with a corresponding support surface (71) of the tongue (38) farther from the lower end of the cut a groove (36), to counteract the mutual displacement of two mechanically connected floorboards in a direction (D1) perpendicular to the surface plane (HP), and all parts of the lower projection (40) that are connected to the core, viewed from (C) ), where the surface plane (HP) and the joint plane (VP) intersect, are located outside the plane (LP2), which is located farther from that point than the interlocking plane (LP1) parallel to it and tangent to the cooperating a locking surface (45, 65) of the tongue groove (36) and tongue (38), wherein said locking surfaces are most inclined against the surface plane (HP), wherein the upper projection (39) and lower projection (40) and tongue (38) of The edges (4a, 4b) are designed to disconnect two mechanically connected floorboards by rotating one floorboard upside down about the pivot center (C) just at the intersection point between the surface plane (HP) and the joint plane (VP) on disengaging the floorboard tongue (38) and the tongue groove (36) of the other floorboard (1).