Mechanical lockings of floor panels and a tongue blank

Background of the Invention

The invention, in a way that does not exclude other solutions, particularly relates to a mechanical retaining system for rectangular floor panels with longer and shorter edges that can be mounted with a vertical bend. It should be emphasized that the names of long and short edges are used only to simplify the description. The panels can also be square, they can have more than 4 edges, and tangent edges can have an angle other than 90 degrees. Nevertheless, the invention is equally applicable to all building panels in general. More specifically, the invention relates primarily to a type of mechanical retaining systems that allow, as a result of bending long edges and vertical displacement of short edges, to immobilize all four edges of the panel relative to other panels, in one operation generally called vertical bend.

Floor panels of this type are disclosed in applications WO2008 / 004960 (applicant Valinge Innovation AB) and WO 2008/017301 (Schulte). The basic operating principles are shown in Figs. 1a-1d.

In Fig. 1a, it can be seen that two adjacent short edges in the first row can be connected to each other by means of a sliding strip (30) which shifts, according to Fig. 1b, as a result of lateral pressure on one of the edge fragments (32) after bending downwards and adjacent short edges 1b, Ic. This vertical collapse, caused by "side interference", which is generally generated by

EP2 391 783 pressure P coming from the long side of the third panel 1d in the second row causes the independent and sliding strip 30 to move along the connection with the short edge 1b, but also perpendicular to the connection in direction D2 in such a way that part of the strip is inserted into the strip groove 20 along the adjacent short edge Ic. Fig. 1b shows the slide bar 30 in the groove for the slide element which has a recess 41. This recess cooperates with the projection 31 of the sliding strip in such a way that as a result of pressure along the edge and the groove on the sliding element, the sliding strip 30 also moves perpendicular to the edge in the direction D2 and slides into the groove 20 on the adjacent panel. FIG. 2a-2d show a known method of forming the recess 41.

The rotary tool 71, analogous to a thin cutting disc, rotates in a horizontal HP plane parallel to the panel surface, forming a recess 41. The main disadvantage is that the tool forms a recess 41 of considerable depth, as seen in Fig. 2d.

This creates a locking system operating on the principle of lateral interference, known according to the state of the art, which requires a groove for the sliding element that is not parallel to the edge, which is very difficult to make, and deep grooves can have a negative effect on the stability and strength of the edge panel. Alternatively, wedge-shaped strips consisting essentially of two parts that are not parallel to the edge may be used. Such slats are expensive and complicated to manufacture and difficult to slide into the edge of another element.

The main disadvantage of this type of side interference systems, compared to other mechanical retaining systems, is that it is difficult to make recesses cooperating with the protrusions on the sliding strips in a precise and economical way, and it is difficult to avoid their negative impact on the stability and strength of the panel edges.

Definition of certain terms

In the following description, the visible surface of the installed floor panel is called the "front surface", while the opposite surface of the floor panel facing the ground is called the "rear surface". The edge between the front and back surfaces is called

EP 2 391 783 "connecting edge". Unless otherwise stated, upper and lower means from the front surface and bottom surface, respectively. Internal and external means respectively towards the center of the panel, or away from the center of the panel. "Horizontal plane" means a plane which runs parallel to the outer part of the surface layer. The upper parts of two adjacent edges adjacent to each other, connecting two floor panels connected together form a "vertical plane" perpendicular to the horizontal plane. By "horizontally" is meant a direction parallel to the horizontal plane, and by "vertically" direction parallel to the vertical plane.

By "joint" or "retaining system" is meant cooperative connecting means that connect floor panels in a vertical and / or horizontal plane. By "slat panel" is meant a panel edge that includes a slat and a retainer, and "inlet panel" means a panel edge that includes a retainer key, cooperating with the retainer element on the horizontal lock.

By "vertical interference" is meant an assembly method in which the short edges of the two panels are joined when they lie flat on the ground after angling. Vertical connection is obtained as a result of side interference, which causes the independent strip to move along the length of short edges. The horizontal lock is obtained in conventional folding systems in the same way as in angle systems, with the retaining element located on one edge of the slat panel, cooperating with the retaining groove located on the other edge of the inlet panel. By "side joining system" is meant a system that can be locked using the method of vertical folding.

By "strip width" is meant the maximum distance between two parallel lines running along the strip length, tangent to the outermost and inner elements of the strip.

Summary of the Invention

The general object of the invention is to improve the functionality and strength of the side interference coupling system, especially those parts that make the sliding strip perpendicular to the edge of one

EP2 391 783 key to an adjacent key when sliding the slide strip along the edge.

According to a first aspect, the floor panels are equipped with a retaining system comprising a sliding strip in the groove of the sliding element along the first edge, and a strip groove along the adjacent second edges, for positioning in a vertical plane. The retaining strip with the retaining element along the first edge cooperates with the retaining groove along the second edge for horizontal locking. The slide has a projection and the key for the slide has a recess to slide the projection along the recess wall in a first direction perpendicular to the edge when the slide is moved in the second direction along the edge. As a result of sliding in the first direction, the sliding strip is inserted into the strip groove in which the edges are locked in the vertical direction. The recess runs vertically down towards the back of the panel.

The advantage of this solution is that recesses can be made as a result of simple machining, and their implementation will not have a negative effect on the strength and stability of the edges.

The recess is, according to a preferred embodiment, a blind hole surrounded by a substantially vertical wall.

This recess provides an extremely stable edge and reduces the amount of material needed to be removed to a minimum.

According to a second aspect, the floor panels are equipped with a retaining system comprising a sliding strip in the groove of the sliding element along the first edge, and a strip groove along the adjacent second edges for positioning in a vertical plane. The retaining strip with the retaining element along the first edge cooperates with the retaining groove along the second edge for horizontal locking. The slide has a projection and the key for the slide has a recess to slide the projection along the recess wall in a first direction perpendicular to the edge when the slide is moved in the second direction along the edge. As a result of sliding in the first direction, the sliding strip is inserted into the strip groove in which the edges

EP 2 391 783 are blocked in the vertical direction. The projection is flexible and made in such a way that it exerts initial pressure on the horizontal groove.

The advantage of this second aspect of the invention is that it allows the negative impact of manufacturing inaccuracies to be reduced and the design quality of the retaining system to be better.

According to a third aspect, the floor panels are equipped with a retaining system comprising a sliding strip in the groove of the sliding element along the first edge, and a strip groove along the adjacent second edges for positioning in a vertical plane. The retaining strip with the retaining element along the first edge cooperates with the retaining groove along the second edge for horizontal locking. The slide has a projection and the key for the slide has a recess to slide the projection along the recess wall in a first direction perpendicular to the edge when the slide is moved in the second direction along the edge. As a result of sliding in the first direction, the sliding strip is inserted into the strip groove in which the edges are locked in the vertical direction. The projection is on the bottom and / or on the top of the sliding bar.

The advantage of the third aspect is that it allows the groove to be formed on the sliding element with a small depth, greater stability and strength.

According to the fourth aspect and according to the invention, the set of floor panels is equipped with a retaining system comprising a sliding strip which has a main strip body and at least two wedge elements arranged in the groove of the sliding element along the first edge of the first floor panel, cooperating to lock the edges in the plane vertical with a groove located on the adjacent, second edge of the second floor panel. The retaining system additionally includes a retaining strip, which has a retaining element on one edge, which cooperates with the retaining groove located on the adjacent edge, allowing the edge to be locked in a horizontal plane. The main body of the strip includes at least two flexible projections and two cavities. Wedge elements are placed at least partly in these recesses. Flexible projections slide along the wedge elements, as a result of which it is possible

EP2 391 783 displacement of the main body of the slat perpendicular to the edge, thereby blocking the vertical movement of the edge. The flexible projections are in the unlocked position, displaced substantially along the slide bar with respect to the wedges, and made in such a way that they exert initial pressure on the wedge elements and the slot groove. The main body of the strip includes a friction connection that allows displacement along the groove on the sliding element, and prevents the main body of the strip from falling out of the groove on the sliding element. The wedge elements comprise a friction connection that prevents the wedge elements from moving inside the keyway on the sliding element when the main body of the strip is moved along the edge. The wedge elements and the main body of the slat contain openable wedge element connectors that open when inserting the sliding slat into the groove on the sliding element.

The advantage of the fourth aspect is that edge forming is possible by simple machining in a direction parallel to the edge in the same way as with conventional mechanical retaining systems. The sliding strip is formed in an economical way as a one-piece element, and transformed into a two-part element during controlled insertion of the strip into the groove.

According to a fifth aspect, also according to the invention, there is provided a frame with slat elements comprising at least two slats of a certain length connected to each other. The slats can be separated from each other and inserted into the edge grooves of floor panels. Each of the slats includes a main slat body that has at least two protrusions extending essentially along the length of the slat, and two cavities. The strip has two wedge elements at least partially inside or next to the recesses. The main strip body and wedge elements include openable wedge element connectors that detach from the main strip body when the strip is inserted into the groove.

The advantage of the fifth aspect of the embodiment is that it allows the production, operation and insertion of groove strips in a simple and economical way.

All embodiments of the first, second, third, fourth and fifth aspects can be combined with each other, so for example, the flexible projection can be used in combination with a running recess

EP 2 391 783 towards the rear surface and on the upper and / or lower side of the slide bar.

The invention makes it possible to implement new embodiments of retaining systems, preferably along short edges, but also along long edges, or in square panels. The scope of the invention includes wall panels, ceilings, exterior solutions and floor panels of any shape and material, e.g. laminate; especially panels with surface materials including thermosetting resins, wood, HDF boards, veneer or stone.

Almost all embodiments of the retaining system were presented with a groove for the sliding element and a sliding strip on the strip panel, mainly to simplify the description. It is obvious that the basic principle of the invention can also be used on the key side. A groove is inserted into the groove for the sliding element made on one edge tangentially to the retaining groove, preferably above it, and a groove is made on the other edge adjacent to the retaining strip, preferably substantially above the slat.

Short description of the figures

Figs. 1a-d show the retaining system according to the prior art.

Figs. 2a-c show a method of producing a recess in a panel edge according to prior art.

Figs. 3a-f show how to form recesses in the panel edge.

Figs. 4a-d show an alternative way of forming recesses in the panel edge.

Figs. 5a-d show a method of forming recesses in a panel edge using a worm cutter.

Fig. 6b show the method of forming recesses in the panel core before applying the surface layer to the core.

Figs. 7a-d show the retaining system with cavities formed by means of cutting discs.

Figs. 8a-e show the retaining system with a recess formed by cutters in the form of a drilled blind hole.

EP2 391 783

<td>retaining</td><td>with</td><td>bar</td><td>sliding</td>

<td>retaining</td><td>with</td><td>bar</td><td>sliding</td>

<td>retaining</td><td>with</td><td>bar</td><td>sliding</td>

Figures 9a-c show retaining systems with open cavities in a horizontal plane formed by cutters.

Figs. 10a-e show a system comprising flexible projections.

Figs 11a-d show a system comprising protrusions at the bottom of the strip.

Figs 12e-f show a system comprising protrusions on the upper and / or lower part of the slat.

Figures 13a-d show the flexible protrusions at the bottom of the slide bar and methods for producing and forming a stable and durable edge.

Figs. 14a-d show the retaining system with cavities formed by vertical cutting discs.

Figs. 15a-b show a retaining system with cavities formed by horizontal cutting discs.

Figs. 16a-b show a retaining system using recesses that are made in conjunction with the molded retention system on the long edges.

Figs. 17a-b show a retaining system with spikes that cooperate with projections.

Figs. 18a-e show a retaining system with spikes cooperating with recesses and an embodiment comprising a sliding strip on an inlet panel.

Figs. 19a-e show the retaining system with a one-piece slide bar, which after insertion is divided into several separate parts.

Figs 20a-d show the insertion of a slat into the groove and the locking of the retaining system according to the invention.

Fig. 21a-c show how to position the slat in the groove.

Figs. 22a-d show the frame with slat elements and the edge of the floor panel during position locking.

Figs. 23a-f show frames with slat elements and a retaining system on the edge of the floor panel during position locking.

Figs 24a-f show embodiments according to the basic principles of the invention.

EP 2 391 783

Description of embodiments of the invention

FIG. 3a-3e show a method of forming recesses 41a-d using milling principles. You can use several cutters 70a-d, a separate cutter for each cavity. Molding can be carried out before or after molding the profile. FIG. 3 shows how with a milling cutter you can make a recess that has a smaller diameter than the cutter diameter. FIG. 3e adjusts the recess that is larger than the cutter diameter if the panel and tool are offset from each other. FIG. 3f depicts a cavity made in the form of a blind hole comprising an upper part of solid material and an opening.

Fig. 4a-d demonstrates that the above-described forming operation can be carried out by means of a cutting disc in which preferably several cutting discs 71a-d, preferably on the same axes, are used to make the recesses 41a-d. The recesses in this case are smaller than the diameter of the cutting discs. They can of course also be equal to or larger than this diameter.

FIG. 5a-d show a method of forming the aforementioned recesses 41a-f with a worm mill. The recesses can be formed in this way on a continuous production line in a very economical way, and with high precision, especially if the position of the panels and the speed of the line are exactly synchronized with the position of the tool and the speed of rotation of the tool. The worm mill 72 can be used as an independent device, or more preferably as an integrated tool with a double-sided tenoning machine. The edge of the panel moves substantially parallel to the rotation axis AR of the worm cutter 72. In this way, it is possible to form any shape, forming circular or acute angles. Milling can take place before, after or parallel to cutting out the profiles.

The location of the recess made on the edge of the panel along its length depends on the position of the first input blade 56a of the tool that contacts the edge of the panel as shown in Fig. 5c. This means that the rotational movement of the tool should be adjusted to the edge of the panel that moves towards it. The distances between the recesses can be very accurate if the rotational movement of the tool is adjusted and synchronized with the speed of movement of the panel relative to the worm cutter. The above adjustment of the position of the first input blade and rotational movement

EP2 391 783 tools can be provided by measuring the position of the panel edge and the speed of movement of the chain or conveyor belt, or a drive device that sets that chain or belt. It is possible to obtain very precise machining of the wells and to make the first well in a fixed place in relation to the edges, with an accuracy of about + - 0.2 mm, or even greater. The diameter 53 of the shown worm mill 72 may preferably be smaller on the input side ES than on the opposite exit side. However, the worm cutter can have the same diameter 53 over the entire length 54. A greater cutting depth with this tool configuration can be achieved by a slight tilt of the axis of rotation relative to the direction of the panel edge feeding.

The pitch 55 of the given tool configuration determines the intermediate distances between the pits. Thanks to this, it is possible to make a large number of recesses and projections at intermediate distances with very high accuracy, along joints of considerable length. The screw milling blade 56 is preferably made of industrial diamonds.

The recesses can also be made with the help of other large rotary tools, analogous to cutting discs, which have cutting blades only on parts of their body. The above is only a simple variant of the auger milling principle, where one rotation allows one cavity to be made. The advantage of this solution is that the intermediate distance between the recesses can be adjusted by adjusting the tool rotation speed or the panel feeding speed.

Planned or unforeseen production interruptions, during which the movement of the panels stops, are a problem if the worm cutter is integrated with milling equipment, because the worm cutter can destroy all indentations in the panel that come into contact with the tool blades. This problem can be solved by using production methods comprising the following steps, some of which may be used individually or in combination with others

a) The panel is always stopped after passing through the worm cutter and after all the recesses on the given panel edge have been made. The above method applies to all planned breaks. After stopping the panel in a given position, the worm cutter is moved away from its edge, which makes it impossible

EP 2 391 783 full implementation of all cavities on this edge. Such panels with partially made recesses are identified and discarded during normal manufacture.

b) After stopping the panel, the worm mill is moved away from its edge. The transport device is then activated in the reverse direction. The worm cutter is moved back to its original position and the panel is processed in the normal way.

c) The worm cutter includes a movable device that allows the cutter to move parallel to the panel edge in the opposite direction to the panels feed when the panels stop moving. The worm cutter is moved in such a way that its blades go through the edge of the stopped panel. In this way, all the cavities will be completely completed, even in the event of an emergency stop. After restarting the transport device, the worm mill returns to its original position and the next panel is made in the normal way.

The method with a sliding worm mill, which is described in point c) above, has the advantage of allowing the use of conventional milling equipment without any modification of the transport device or control systems.

The above-described methods for producing cavity forming with a worm mill can be used for any type of panel treatment, and especially for machining for manufacturing cavities, which includes components of a mechanical retaining system for floor panels.

Figures 6a-b show how recesses can be made before profile machining. The edge of the floorboard can be joined to a separate material 62 or a panel core with projections, recesses 41a, preferably glued between surface layer 60 and leveling layer 61 as part of a wooden floor or laminate floor.

Figs. 7a-d show how the described methods for making recesses in the edge can be used to move the slide bar 30 from one keyway to the slide element 40 to the adjacent keyway 20, as shown in Figs. Ia-Id. It is possible to make one or several recesses 41a-c with vertical walls, converging or parallel, by cutting through a slat 6, such an embodiment and such a method

EP 2 391 783 production is more economical than the production methods of the prior art, in which thin horizontal cutting discs are used to make the recesses. The recesses can advantageously be made by means of step cutting heads 71a-71c, mounted on one tool shaft, which move towards the rear side of the panel when the panel moves relative to these heads. The panel can of course also move vertically or horizontally towards the cutting heads. Jumping heads can be mounted on the same device that is used to make longer edges, and recesses can be made in an economical way, in parallel with the performance of the fixing system. The step heads can also move along the feed direction, and the relative speed difference between the step heads and the edge of the panel can also be used to make recesses with holes larger than the width of the rotary tools. Non-rotating disc scraper tools can also be used to make recesses or protrusions. FIG. 7c shows the slide bar in the unlocked position in which its protrusions 31a-c are in recesses 41a-c. FIG. 7d shows the locked position in which the slat 30 has been moved along the edge as a result of lateral pressure P applied on the section 32 of the edge of the slat 30. During this displacement, the projection will move along the walls of the recesses, forcing the perpendicular movement PD of the strip in relation to the edge, and its connection with the adjacent strip groove 20.

FIG. 8a-8e show an embodiment in which the recess 41a is a blind hole. A cutter with a diameter of, for example, 5-15 mm can be used and one or several recesses 41a-41c in the form of blind holes can be made from the back of the panel, as shown in Fig. 8a-8c. During machining, the panel and / or cutter approach each other in a vertical direction. The recesses can be arranged in relation to each other in such a way that when interconnected panels cooperate with protrusions 31a-31d, located on the inside of the slat 30, as shown in Fig. 8d-8e. Such an embodiment ensures the creation of very durable and stable edges, because the milling machine removes only small amounts of material.

Figures 9a-9c show an embodiment with the recesses 41a-d made by milling cutters, wherein during machining the milling cutter and / or panel

EP 2 391 783 move each other horizontally. In some cases, the use of this production method may have some advantages. For example, the milling cutters can be stationary or mounted on a step cutting head, which can also be slidable along the feed direction of the panels.

FIG. 10a-10e demonstrate that the protrusions 31a-c can be flexible, which can be used to compensate for manufacturing inaccuracies and to cause horizontal pretension between the slat 30 and the slot groove 20, which will allow a vertical pressure force VF to arise between the upper part of the slat 6 and the adjacent panel as shown in fig. 10d. The vertical contact force VF is preferably caused by the contact surface between the slat 30 and the groove 20, which are slightly inclined relative to the horizontal surface HP.

Figures 11a-d demonstrate that the projections 31a-c, which cooperate with the recesses 41a-c when interlocking the panels, can be made, for example, on the bottom of the slide strip 30. The depth of the groove for the slide element 40 can be significantly reduced, which will result in greater moisture resistance and bond strength.

Figures 12a-12f demonstrate that the projection 31a-c, 31a'-c 'can be made on the upper and / or lower part of the slide bar 30. Such projections can cooperate with the depressions 41a above and / when the panels are locked; or below the main body of the slide bar 30.

FIG. 13a, 13b show that it is possible to make flexible projections 31a that extend down and / or up from the main body of the slide bar 30. The above projections can generate initial stresses in the same manner as described above with reference to Fig. 10a-d. FIG. 13c and 13d show that the projection 31a on the bottom of the slide bar 30 allows the recess 41a to be made with a much smaller depth, as shown in Fig. 13d, thanks to which edge strength can be increased. The recesses made with the vertical rotary tool 71 preferably have a lower portion 81 which is located in a vertical direction inwards relative to the upper portion 82 of the recess. This ensures adequate edge strength and stability, and allows cost-effective production.

Figures 14a and 14b show the sliding strip 30 with protrusions 31a, b at the bottom, and with depressions 41a, b made by rotating discs

EP2 391 783 cutting. FIG. 14c, d show that all embodiments of the depressions and protrusions can be used to induce counterpressure P 'and to bend the flexible bar 30'. The projection 31a cooperates with the recess 41a and prevents the strip from moving after applying lateral pressure P. The lath 30 bends and locks in the lath. This can be used to lock the panels in the first row, where it is impossible to obtain counter-pressure from the long side of the adjacent row to bend the slat.

FIG. 15a, b show that horizontally rotating cutting discs 71a-c can be used to make recesses 41a-c that are above and / or below the main body of slide strip 30 and which cooperate with projections 31a, b above and / or below the main strip body. One cutting disc 71a may be offset in a vertical plane relative to the other cutting disc 71c. These manufacturing methods and embodiments can be used to make grooves for sliding elements 40 of a small depth, or to increase the angle A1 of the perpendicular displacement.

FIG. 16a, b demonstrate that it is possible to move the slide bar 30 in the transverse direction to the connection, without any further processing outside the range required to make the retaining system on long and short edges. On each of the edge sections of the slat 30, protrusions 31a, 31b can be made, which cooperate with the slotted groove 9 and retaining groove 14 of the long edge. The projection 31b, which cooperates with the retaining key 14, is in this embodiment flexible and is located on the bottom side of the main body of the strip. This principle can also be used to bend the flexible strip described in Fig. 14c. The projection may be rigid and may for example be made as a straight wedge protruding downwards. The vertical extension of the projection 31b should allow the retainer 8 to be adjacent the long edge in the retaining groove 14 and below the projection 31b, as shown in Fig. 16a.

Fig. 17a, b shows that the spikes 42a, 42b can be used to form a vertical wall in the groove for the sliding element 40, and to move the sliding strip 30 in a perpendicular direction PD for connection. In the illustrated embodiment, the displacement is caused by one or several cooperating pairs of spikes 42a, b and projections 31a, b. Spikes 42a, b can be made of metal, e.g. soft steel or aluminum,

EP 2 391 783 of plastics or even of hardwood. Such embodiments can also be used to bend the flexible bar. The spikes can of course be connected to the keyway on the sliding element 40 horizontally or at an angle.

FIG. 18a, b show that the offset can also be obtained by means of one or several spikes 42a, b, which cooperate with one or several cavities 42a, b, preferably made on the inside of the slide bar 30. The sliding strip in this embodiment comprises one of several friction joints 44a, b, which are preferably flexible in the vertical direction, and which prevents the strip from falling out of the groove on the sliding element 40. It is possible to use other types of friction joints.

FIG. 18c-e show an embodiment comprising a strip 30 located in the inlet panel Ic, which is intended to be folded over the strip panel 1b. 18c and 18d show the slide bar 30 in the unlocked position, and fig. 18e shows a locked position where the sliding strip 30 is inserted into the slot 40. The perpendicular displacement in this embodiment is generated by the cooperation between one or several protrusions 31a-c, located on the bottom side of the slide bar, and one or more recesses 41a-c, which in this case are located below the main body of the bar. The recesses (41a-c) can preferably be made with worms. Such an embodiment has several advantages. To make a recess, it is necessary to remove a small amount of material from the edge of the panel. The recesses are also easy to make because no strip protrudes from the edge. Sliding strip 30 can furthermore be easily inserted into the groove of the sliding piece, which may have a small depth due to the fact that projection 31a and recess 41a are led down from the bottom of the main body of the strip.

FIG. 19a-e show a slide bar 30 according to one embodiment of the invention. The sliding strip 30 is made as one piece, preferably during injection molding, preferably of thermoplastic material. FIG. 19a shows a slide bar 30 comprising a main bar body 30a and one or more wedge elements 45a-e which are connected to the main bar body by means of wedge element connectors 46a-e, preferably located partly in the recess cavities

EP2 391 783

43a-e made in the main body of the strip (30a), or next to them. The wedge elements contain wedge friction connectors 47a, b.

The main body of the slat 30a includes one or more friction fasteners 44 and one or more flexible projections 31a-e, preferably directed in the length direction of the slat slat body 30a.

Figs. 19b-19e are an enlargement of the strip section shown in Fig. 19a.

Slat friction fittings 44 are preferably flexible. Such slat friction connectors that can be used to generate controlled preload on the upper and / or lower groove wall of the sliding element 40 keep the groove in the groove of the sliding element in a controlled manner, and prevent the groove from falling out of the groove on the sliding element. Flexible slat friction fittings 44 enable even and easy sliding along the joint and eliminate the need to maintain high precision when manufacturing and making the key for the sliding element. The wedge elements 45 comprise one or more wedge friction connectors 47, which can be made in the form of small, vertical projections. These projections can also be flexible.

Wedge friction joints 47 should preferably be made in such a way that they cause more friction than friction caused by slatted friction joints 44. Wedge friction joints 47 should provide a strong connection between the wedge elements 45 and the keyway on the sliding element 40 to prevent the wedge element 45 from displacing during sliding of the main strip body 30a along and perpendicular to the joint when the panels are interlocked. This type of strong connection can be realized, for example, by means of a key for the sliding element, which is made with a vertical opening that is smaller in the inner part than in the outer part of the key. During interlocking of the panels, when the main body of the strip 30a exerts pressure in the inner direction on the wedge element 45, the inner part of the wedge friction connector can be pressed against the upper and lower part of the groove for the sliding element.

Fig. 19b demonstrates that in the delivered condition of the slide bar, when it is not connected to the edge of the panel, the wedge element 45 forms the outer part of the slide bar. The outer part of the wedge element 45 partially projects beyond the main body of the strip 30a. The width of the sliding strip

EP 2 391 783

TW 1 is larger than the width of the main body of the TW 2 strip. The wedge element comprises an oblique or rounded inclined surface 48a and a connecting surface 49, which in this case is preferably substantially vertical. The projection 31 of the flexible strip includes an oblique or rounded sloping surface 48b, which is designed to cooperate with the sloping surface 48a of the wedge, and cause the displacement of the slide strip perpendicular to the panel edge after applying side pressure P to the edge section of the slide strip. The protrusion 31 of the flexible strip and the wedge element 45 preferably have overlapping elements along the width direction, as indicated by the line L1. The wedge inclined surface in the illustrated embodiment is inclined at an angle of 45 degrees relative to the length direction of the slide bar 30. It is possible to use a slope at a different angle. Preferred inclination angles are around 25-60 degrees.

FIG. 19c shows that after inserting the slide bar 30 into the keyway of the slide element 40 and pressing it against the inner part 40 'of the keyway 40, the wedge element 45 is preferably detached from the main body of the strip 30a. The wedge element connector 46 should preferably be designed so that it breaks off when the wedge element 45 is pressed into the recess 43 in the main body of the strip. Alternatively, the wedge element 45 may be partially disengaged before inserting the slide bar 31, or after applying lateral pressure P when locking the elements. When the slide bar is in the unlocked inner position, the sloping surfaces 48a, 48b are preferably tangential, or at least overlap, along the width of the slide bar. This solution allows reducing the displacement distance DD required to obtain a fixed LD blocking distance.

FIG. 19d shows the position of the main body of the slat 30a and the wedge element 45 after applying lateral pressure P on the edge of the main body of the slat 30a, and after displacement of the main body of the slat along the groove on the sliding element 40 up to the final locked position at the distance LD, where it has the greatest width TW 3 strip and in which it is connected to the inner part of the strip groove 20 on the edge of the adjacent panel. The sliding strip is preferably designed in such a way that allows further displacement of the main strip body, enabling

EP2 391 783 target angular bend and locking of the next panel 1d in the next row, as shown in Fig. 1b. FIG. 19e shows that such further displacement along the edge causes the flexible projection 31 to bend outwardly towards the outer parts of the main body of the strip, and the slide strip can be locked as a result of pre-stresses. The flexible projection is a basic element of this embodiment, and can be used to eliminate the negative impact of manufacturing inaccuracies that arise when shaping the keys and inserting the strip into the key. Such an embodiment that allows the DD displacement distance to be increased while maintaining a substantially constant LD blocking distance allows for higher blocking quality and reduced manufacturing costs.

The protrusion 31 can be made in such a way that the pretension increases when the main body of the strip moves during the final blocking of the elements according to Fig. 19e. The preload can also be constant according to Fig. 24a.

According to one embodiment shown in fig. 19e, the projection 31 can be made in such a way that it can bend horizontally inwards and outwards during locking, but also in a vertical direction towards the top or bottom of the groove for the sliding element. The above vertical flexibility can be used to form a 44 'friction fastener that will prevent the main strip body from falling out of the key on the sliding element 40. The advantage is the possibility of making the stiffer strip body, without the need for any additional flexible friction connectors on the main strip body apart from the protrusions (31).

The sliding bar in this embodiment has three widths. The maximum width TW 3 when in the locked position, the minimum width TW 2 when it is in the unlocked position, and the intermediate width TW 1 with a value between the maximum and minimum width in the factory condition, not connected to the edge of any panel.

The minimum width of the TW 2 strip is preferably about 4-6 mm, the maximum width of the TW 3 strip is preferably 5-8 mm, and the intermediate

The width of the TW 1 strip is preferably 5-7 mm. The blocking distance is preferably 1-3 mm and the displacement distance DD about 2-5 mm.

FIG. 20a-b demonstrates how to slide the slide bar 30 into the keyway on the slide element 40 by means of a pusher 67. The keyway for the sliding element 40 comprises pairs of opposing and substantially parallel keying surfaces 40a, 40a 'and outer 40b, 40b'. The vertical distance between the inner inlet surfaces 40a, 40a 'is smaller than the distance between the outer surfaces 40b, 40b'. Such a groove can be used to separate the wedge member 45 in a controlled manner during insertion because the wedge member is detached after the main body of the strip 30a is inserted into the groove, and this prevents the wedge element from turning or twisting during insertion. FIG. 20c is a cross-sectional view of the retention system in the unlocked position, and FIG. 20d in locked position.

It is very important that the strip is attached to the groove for the sliding element in a fairly precise way. This can be achieved by means of an insertion device which slides the slat into the groove and a positioning device 90 which positions the slat at a fixed and exact distance from the corner of the panel after insertion, according to Fig. 21a-21c. Positioning device 90 includes a surface 91 in contact with the panel and a surface 92 in contact with the edge of the bar. These surfaces can be centered or offset in the feed direction line by a fixed TD distance. The sliding strip is preferably always connected in a position that requires displacement in one direction, preferably in the opposite direction to the feeding direction, FD, as shown in Fig. 21a. The slide strip 30 automatically obtains a predetermined inlet distance TD (which may be zero) when the contact surface 91 contacts the panel with the panel edge, preferably running perpendicular to the feeding direction FD, as shown in Fig. 21b. FIG. 21c shows that for final assembly of the strip in the final position, a pressure wheel 93 can be used. The substantially vertical wedge connecting surfaces 49, shown in fig. 19c, make it easier to push the slide bar in a controlled manner.

The displacement and adjustment of the position in both directions can be enabled, for example, by means of a chain or tape, including a series of pushers, with contact surfaces 91 with the panel and contact surfaces

EP2 391 783 with the edge of the strip. The chain / belt speed can be increased and decreased in a controlled manner depending on the speed of movement of the panels in such a way as to make contact between the pushers and two opposite edge elements running perpendicular to the feed direction, and that the strip is pushed along, or opposite to the feed direction, to previously determined location.

The manufacturing methods described above can be used to position any type of slat within each retaining system.

The above-described manufacturing methods, including insertion and positioning of the slat, however, require the slat body and wedge elements to be moved within the keyway, which may cause blocking problems, due to, for example, loose wedge elements that may slide during blocking. The strip is therefore most preferably connected and placed in a predetermined position during connection, and does not require any additional adjustment. Correctly precise insertion of the strip into the groove is possible if the speed of the pusher or hammer 67, which is responsible for the insertion of the strip, is synchronized with the speed of the chain or belt, which move the edge of the panel relative to the insertion device. Correctly precise introduction of the strip in a controlled manner can be used to insert all types of strips or independent elements into the outlets.

One recess and one wedge element may be sufficient to obtain blocking of the elements, especially in the case of using a flexible protrusion on one edge section, which cooperates with the corner section of the panel. However, it is preferred to use at least two slat recesses and wedge elements. This type of embodiment ensures easier and more controlled movement, and more permanent fixation of elements in the vertical direction.

Fig. 22a shows a frame 80 with slat elements that includes several sliding slats 30 according to an embodiment of the invention.

Fig. 22b shows a slide bar 30 that has been detached from the frame 80 with the bar elements. Fig. 22c shows the slide bar in a connected state in which the wedge elements 45 have been detached from

EP 2 391 783 of the main body of the lath 30a. Fig. 22d shows the sliding strip 30 in the outer and locked position after applying lateral pressure P to the edge of the strip.

FIG. 23a shows that recesses 43 'can be made in the main body of the strip, which saves material. FIG. 23b shows that wedge elements 45 can be connected to a fixed wedge connector 63. FIG. 23c-f show that wedges can be positioned automatically without the need for any friction joints. The main body of the strip 30a moves the stationary wedge 63 until the edge of the stationary wedge 63 contacts the perpendicular edge 64, generally the long edge, of an adjacent panel in an adjacent row, as shown in Fig. 23d. Wedges are not able to move further, and the main body of the lath 30a will slide perpendicular to the edge, as shown in Fig. 23e.

Fig. 23g shows that the fixed wedge connector may have a wedge hook 69 connected to a keyway made on an edge perpendicular to the main body of the strip 30a. The groove, which is generally used to receive the long edge of the panel, has a greater depth 66 in this case, which is preferably made with a step head tool. The advantage of this solution is that the wedge connector does not have to be adjusted to the panel width.

Fig. 24 a shows that the projection 31 and / or the wedge element 45 can be flexible and exert initial pressure on the bar groove.

Figures 24b-24d show that the protrusions 31a, 31b can be made on both sides of the wedge and that the displacement of the main body of the strip 30a is possible in both directions along the edges. The wedge element connector 46 in this embodiment is located on the outer portion of the wedge element 45.

FIG. 24e and 24f show a simple way to implement a friction connection that prevents any displacement of the slat causing it to fall out of the groove on the sliding element 40. A sliding bar 30 is provided, which is slightly bent in the vertical direction along its length. This bend may concern the entire length of the slat, or its selected sections, and may be used to exert initial pressure on the lower and upper part of the groove on the sliding element 40. After disconnecting from the frame with slat elements, the slat

EP2 391 783 is preferably compressed by the insertion device, which eliminates bending of the strip, and is inserted into the groove. Flexion can be achieved in many ways. Simple bending of a strip made of HDF board can be obtained, for example, by local pressure 68 on the upper and / or lower side of the main body. It is also possible to use materials of different densities, for example by processing HDF board basically on one side only. The HDF board can also be reinforced and bent in a controlled manner, for example if a layer, preferably a paper impregnated with thermosetting resin, is used only on one side of the board. Such a layer can be laminated and made together with the surface structure, facilitating the sliding and causing a set friction value on the groove surface. The above-described friction connection can be used independently to connect any type of slat, preferably a sliding bar, to a groove, or together with other friction connections or slats according to the described embodiments.

All embodiments of the slats can be made of materials containing wood fibers. Such materials may be, for example, wood fibers mixed with thermoplastic resins or thermosetting resins containing wood. Injection molded or sheet materials can also be used. A preferred material is HDF board, preferably HDF board with a density exceeding 700 kg / cm2. Combinations of forming methods such as machining and / or punching and / or pressing materials can be used to make slats or frames with slats of rather complicated, three-dimensional shapes, or as part of various solutions in which, to block the edges of adjacent panels, preferably floor panels, separated and / or sliding strips are used. This type of production method is very economical and environmentally friendly.

EP 2 391 783