Abstract
The present invention relates to a method for producing a profiled strip (1) comprising: a first longitudinal side (2A), provided with first male connecting means and a second longitudinal side (2B) situated opposite the first longitudinal side (2A) and provided with first female connecting means, which profiled strip (1) is furthermore provided, on a first end side (3A), with second male connecting means and is provided, on a second end side (3B) situated opposite the first end side (3A), with second female connecting means, wherein said connecting means are suitable for connecting the longitudinal sides (2A, 2B) and/or the end sides (3A, 3B) of adjacent profiled strips (1, 1) to each other, wherein the method comprises the following steps: supplying a panel-shaped profiled section made of plastic; sawing the profiled section produced to the desired length; performing one or several milling operations in order to produce at least one foldable flexible projecting element (6a) on the first end side (3A) of the sawed profiled section; heating the produced projecting element (6A) and subsequently bending it at a desired angle in relation to the end side (3A) in order to form a bent locking element (6b).
Claims
1. Method for producing a profiled strip comprising: a first longitudinal side, provided with first male connectors and a second longitudinal side situated opposite the first longitudinal side and provided with first female connectors, which profiled strip is furthermore provided, on a first end side, with second male connectors and is provided, on a second end side situated opposite the first end side, with second female connectors, wherein said connectors are suitable for connecting adjacent profiled strips to each other by the first or second male connectors engaging in the first or second female connectors, wherein the method comprises the following steps: supplying a panel-shaped profiled section made of plastic; sawing the profiled section produced to the desired length; performing one or several milling operations in order to produce at least one foldable flexible projecting element on the first end side of the sawed profiled section; heating the produced projecting element and subsequently bending it at a desired angle in order to form a bent locking element.
2. Method for producing a profiled strip according to claim 1, wherein the produced projecting element is bent to bear against the body of the profiled strip.
3. Method for producing a profiled strip according to claim 1, wherein the profiled strip comprises a visible side with at least one transparent wear layer.
4. Method for producing a profiled strip according to claim 1, wherein the profiled strip is made from plastic.
5. Method for producing a profiled strip according to claim 1, wherein the profiled strip comprises one or several mineral fillers.
6. Method for producing a profiled strip according to claim 1, wherein the profiled strip comprises a number of process stabilizers for heat resistance during processing.
7. Method for producing a profiled strip according to claim 1, wherein, after the produced projecting element has been bent, this element is temporarily held in a bent position while it is being cooled down.
8. Method for producing a profiled strip according to claim 1, wherein, a first inwardly directed recess is also provided on the first end side during the execution of said milling operations.
9. Method for producing a profiled strip according to claim 8, wherein a second inwardly directed recess adjoining the first inwardly directed recess is provided during the execution of said milling operations.
10. Method for producing a profiled strip according to claim 9, wherein the produced projecting element is bent after heating in such a manner that it bears against the transition between the first and second produced recess.
11. Method for producing a profiled strip according to claim 1, wherein the profiled strip comprises a decorative top layer.
12. Method for producing a profiled strip according to claim 1, wherein the profiled strip has a thickness of between 3 mm and 12 mm.
13. Method for producing a profiled strip according to claim 1, wherein the profiled strip has a thickness of between 4 mm to 6 mm.
14. Method for producing a profiled strip according to claim 1, wherein the produced bent locking element is directed upwards.
15. Method for producing a profiled strip according to claim 1, wherein the produced locking element is directed downwards.
16. Method for producing a profiled strip according to claim 1, wherein the produced locking element has a thickness of between 0.2 mm and 1.2 mm.
Description
[0031] In this description, reference numerals are used to refer to the attached drawings, in which:
[0032] FIG. 1: shows the bending of a projecting element which has been formed by means of a milling operation in order to form a bent locking element (6b) suitable for producing a vertical lock between two adjacent profiled strips;
[0033] FIG. 2a: is a representation of the connection of a possible embodiment of the first end side as illustrated in FIG. 1, with the second end side or the second longitudinal side of an adjacent profiled strip;
[0034] FIG. 2b: is an illustration of the distance (AB) between the distal end of the flexible part of the bent locking element (6b) and the location where the flexible part bears against the profile body;
[0035] FIG. 3: shows a diagrammatic cross section of an alternative profiled strip manufactured according to the method according to the invention;
[0036] FIG. 4: shows the connection of two adjacent profiled strips, as shown in FIG. 3, by means of their end sides;
[0037] FIG. 5: shows, in parts I-IV, the various steps of producing the locking element on a profiled strip manufactured according to the method according to the invention;
[0038] FIGS. 6 and 7: show, in steps, two different ways of bending a projecting element in order to produce a locking element;
[0039] FIG. 8: shows, in steps, an alternative way of producing a locking element by means of a milling operation;
[0040] FIG. 9: shows, on the one hand, a number of possible embodiments of the projecting element (6a) (FIGS. 9a, 9c, 9e and 9g) and, on the other hand, in the bent position, in which the locking element (6b) is formed (FIGS. 9b, 9d, 9f and 9h);
[0041] FIG. 10: shows an embodiment of profiled strips manufactured according to the method which are connected to each other, wherein the bent locking element (6b) is relatively thick, and wherein only a first inwardly directed recess is provided in the first end side, no second inwardly directed recess;
[0042] FIG. 11: FIGS. 11a-11c show a number of steps of the method wherein, by means of a milling operation, a projecting element was produced in one of the female connecting means (FIG. 11b) which was then bent by means of heat to form a bent element (FIG. 11c); FIG. 11d shows two profiled strips in a connected position;
[0043] FIG. 12: is a representation of a number of profiled strips according to the invention which are connectable to each other.
[0044] A profiled strip (1) comprising: a first longitudinal side (2A), provided with first male connecting means and a second longitudinal side (2B) situated opposite the first longitudinal side (2A) and provided with first female connecting means, which profiled strip (1) is furthermore provided, on a first end side (3A), with second male connecting means and is provided, on a second end side (3B) situated opposite the first end side (3A), with second female connecting means, wherein said connecting means are suitable for connecting the longitudinal sides (2A, 2B) and/or the end sides (3A, 3B) of adjacent profiled strips to each other is illustrated in FIG. 12. Such a profiled strip is produced by means of a method which comprises at least the following steps: [0045] supplying a panel-shaped profiled section made of plastic; [0046] sawing the profiled section produced to the desired length; [0047] performing one or several milling operations in order to produce at least one foldable flexible projecting element (6a) on the first end side (3A) of the sawed profiled section; [0048] heating the produced projecting element (6a) and subsequently bending it at a desired angle in order to form a bent locking element (6b).
[0049] The produced locking element is a locking lip which is formed by first performing a milling operation, thereby forming a projecting element (6a), heating this element (6a) and bending it to form a bent locking element (6b). The distal end of the bent locking element (6b) does not make contact with the profile body, as a result of which it is displaceable (depressable), as a result of which it will be displaced in the direction of the profile body while connection to an adjacent profile takes place and it will return to its original position after the connection has been achieved and will consequently, in the connected position, as illustrated in FIGS. 2a and 4 produce a vertical lock (see the circled area denoted by reference numeral 4) in which the distal end of the bent locking element (6b) can make contact with a locking part (denoted by reference numeral 5) of the female connecting means which cooperates with the bent locking element (6b). In practice, this locking part is formed by providing an inwardly directed recess in the respective side of the adjacent profiled strip (1).
[0050] FIG. 5 shows, in various steps (I-IV), a possible embodiment of the method according to the invention. In this case, the first end side (3A) is initially (step I) subjected to a milling operation in order to produce the required corresponding recesses and projections so as to produce the (hook-shaped) connecting means. In addition, the projecting element (6a) is provided on the first end side (3A) by means of a milling operation, which element will be bent later by means of heating. Heating will be effected by means of a heating element, e.g. infrared heater, an industrial heater or a heating nozzle with hot air which will bring the material to the suitable temperature at which the material of the projecting element (6a) becomes mouldable. Preferably, the produced projecting element (6a) is heated at the location of its base (13) (see circled area in step II). The base (13) of the projecting element (6a) is the location where the projecting element (6a) adjoins the profile body of which it forms part. Once the material is mouldable, the projecting element (6a) is bent (step II) by means of an element, which was developed specifically for the purpose, so as to be bent at a desired angle in the direction of the respective profile body and to be held there temporarily until the material has cooled down. In a preferred embodiment, the projecting element (6a) is actively cooled while it is being held (step III), for example by passing coolant through the element which will temporarily hold the projecting element (6a). After cooling, a bent locking element (6b) is formed which preferably partly bears against a part of the profile body, preferably this part is curved and forms a support for the bent locking element (step IV). The distal end of the bent locking element (6b) does not bear against the profile body, but is situated at a small distance therefrom, as a result of which it is displaceable (depressable) only to a very slight degree. Such an embodiment makes it possible for the bent locking element (6b) to at least be displaced partly in the direction of the profile body while connection takes place in order thus to facilitate the locking operation. After the connection has been achieved, the displaced part of the bent locking element (6b) will return to its original position, to that it will make contact, in the connected position, with a wall of the female connecting means and will be locked. The bent locking element (6b) and the locking part (5) cooperating therewith of an adjacent profiled strip is provided in order to produce a vertical lock (4) between adjacent profiled strips (1,1).
[0051] FIGS. 6 and 7 also show two possible other embodiments of the method according to the invention, in which the distal end of the bent locking element (6b) is directed towards the underside (being the side opposite the visible side (V)) of the profiled strip (1) after bending a milled projecting element (6a).
[0052] A profiled strip (1) which is provided with a bent locking element (6b) which has been produced by means of thermoforming, wherein a milled projecting element (6a) is heated and subsequently bent, has the advantage that the freedom of design for the bent locking element (6b) is relatively great. The milled projecting element (6a) and the bent locking element (6b) formed therefrom may be dimensioned such that such profiled strips (1,1) can readily be locked to each other by applying only a small force (pushing with a thumb), whereas many other connecting systems require a great force (use of a hammer). In addition, two profiled strips (1,1) connected to each other can easily be disassembled without the risk of the bent locking element (6b) breaking off.
[0053] According to a preferred method, in order to produce the aforementioned support for the bent locking element (6b), as is visible, inter alia, in FIGS. 1 to 5, a first inwardly directed recess (9) and a second inwardly directed recess (10) adjoining the former are provided on the first end side (3A) during the execution of said milling operations, as is shown in FIG. 2b, and the produced projecting element (6a) is bent after heating in such a manner that it is situated against the transition between the first and second produced recess. Preferably, the second recess (10) is deeper than the first recess (9). The recesses (9, 10) adjoin one another, as can clearly be seen in FIGS. 1 and 2. In this embodiment, they have a curved configuration. In this case, in this embodiment, the transition (12) between the first (9) and second recess (10) will form a contact surface (support surface) for the bent locking element (6b), as illustrated in FIG. 2b.
[0054] The respective recesses (9 and 10) allow for greater flexibility of the bent locking element (6b) and make it possible to disassemble the profiled strip (1) again after it has been connected to an adjacent profiled strip (1) without causing damage, such as the bent locking element (6b) breaking off at the base (13). The reason for this is that, in practice, disassembling will occur by means of a tilting movement at the end side (3A; 3B) of the connected profiled strips with respect to each other. The various possible embodiments of transition (12) between the second recess (10) and the first recess (9), more specifically the depth of the second recess (10), will, in a number of embodiments, contribute to greater flexibility of the flexible part of the bent locking element (6b), which is a requirement in order to be able to disassemble the respective profiled strips by means of a tilting movement. Because of the greater flexibility of the bent locking element (6b) as a result of the foregoing, the bent locking element (6b) will consequently break off less easily at its base (13) when tilting the foldable lip away in a direction away from the transition (12) when disassembling the adjacent profiled strip.
[0055] In addition, the force to be exerted vertically in order to connect the profiled strips (1,1) to each other, will, in various ways and depending on the type of base material, be made greater or less great. This force to be exerted vertically defines whether a vertical force is to be exerted using a hammer or whether a vertical pressure exerted only by a thumb (or another finger) suffices to produce a lock.
[0056] The fact is that, as can be seen in FIGS. 9, 10 and 11, the depth and shape of the first and/or second recess may be modified. In a specific embodiment, the second recess may also be omitted (see, inter alia, FIGS. 9g and 9h, FIG. 10 and FIG. 11).
[0057] By modifying the depth of the first recess (9), the thickness and the design of the projecting lip of the bent locking element (6b) may be modified. As is illustrated in FIG. 10, a deeper first recess (9) makes it possible to make the bent locking element (6b) (lip) thicker. Whereas most figures show a locking lip having a thickness of 0.5 mm, the locking lip shown in FIG. 10 has a thickness of 0.8 mm. It is also possible to modify the shape of the projecting lip (6b). The addition of a constriction (see e.g. FIG. 9a) will contribute to the flexibility of the lip. These modifications to the embodiments of the bent locking element (6b) of the recess(s) will have an effect on the vertical locking force to be exerted without adversely affecting the actual vertical locking strength of the profiled strips after installation.
[0058] In the embodiment illustrated in FIG. 10 as well, the vertical locking strength may be increased by, on the one hand, making the first recess (9) deeper and, on the other hand, making the projecting element (6a) (and consequently also the locking lip formed therefrom (its bent element (6b)) thicker. Although normally the locking lip has a thickness of between 0.2 and 0.8 mm, this embodiment makes it possible to make the locking lip thicker, up to between 0.8 mm and 1.2 mm.
[0059] In the embodiment as illustrated in FIG. 2b, which, in addition to the flexible bent locking element (6b), also uses two recesses (9 and 10) on the end side (3A) (in particular the first recess (9) and the second recess (10)), the vertical locking force may also be controlled by modifying the distance (AB). In this case, (A) is the point at which, after bending, the bent locking element (6b) comes in to contact with the part of the profiled body which forms the support and (B) is the distal end of the bent locking element (6b). By increasing or decreasing this distance (AB), the vertical locking force to be applied will also increase or decrease, without having an adverse effect on the actual locking strength on the end or longitudinal sides after installation of the profiled strips.
[0060] FIG. 8 shows an alternative method in which a bent locking element (6b) can be produced, albeit without applying the bending procedure, but by using a milling operation.
[0061] As is clear, inter alia, from FIG. 2a, the second end side or the second longitudinal side is of a female design, suitable for accommodating the second male connecting means. In a possible embodiment, the second end side or the second longitudinal side comprises a flexible projection (7) and the first end side furthermore comprises a recess (8), wherein the flexible projection (7) is configured to perform a bending movement in the direction of the adjacent longitudinal or end side while the adjacent profiled strips are being connected in order then to at least partly bend back into its original position when engaging the first or second male connecting means in the first or second female connecting means. Said flexible projection (7) will also produce a vertical lock by engaging in the adjacent recess. However, such a projection (7) and corresponding recess (8) is not required and may, as can be seen from FIGS. 3 and 4, equally well be omitted. As omitting the respective projection (7) and corresponding recess (8) may have a negative impact on the vertical locking strength, this may, as has already been explained, be compensated for by modifying the designs of the bent (locking) element (6b) and/or modifying the design of the end side where one or two recesses (9, 10) may be provided.
[0062] The profiled strips produced by means of the method are preferably elongate floorboards which are substantially composed of a polymer or polyolefines. Obviously, other embodiments, such as e.g. square, or wall parts provided with connecting means as described in the present text also fall within the scope of protection of the present invention.
[0063] In a connected position, the floorboards define a vertical surface. The materials for producing the profiled strip (1) which may possibly be used depend on the mechanical properties. The profiled strip (1) has a decorative finish on the top side. The profiled strip according to the present invention preferably has a thickness of between 3 mm and 12 mm, in particular a thickness of 4 mm to 6 mm.
[0064] The profiled strip (1) produced by means of the method is made in a single part and comprises a visible side (V) having at least one transparent wear layer. The profiled strip is made from plastic, preferably PVC or polyolefines. The profiled strip comprises one or several mineral fillers, possible fillers being chalk or talc. Preferably, at least 2%, more particularly at least 10% fillers are present in the profiled strip. The profiled strip (1) furthermore preferably comprises a number of process stabilizers for the heat resistance during processing, such as for example lead (Pb), calcium-zinc (CaZn) or tin (Sn).
[0065] The bent locking element (6b) in the profiled strip (1) produced in accordance with the method may be directed upwards (see, e.g. FIGS. 1, 2, 3, 4, 5, 9 and 10) in the connected position of two adjacent profiled strips. The bent locking element (6b) may also have different embodiments by giving the projecting element (6a) a well-defined design by means of a milling operation, as is shown in FIGS. 9a to 9h.
[0066] Using the method according to the invention, it is also possible (see FIGS. 6, 7 and 11) to produce a downwardly directed bent locking element (6b). In this case, the side of the profiled strip where the bent locking element (6b) is to be arranged is subjected to a milling operation in order to produce a projecting element 6a (see FIG. 11b). Subsequently, this may be heated, bent and, optionally, allowed to cool, as has been described above, so that a downwardly directed bent locking element (6b) (see FIG. 11c) is produced. Such an embodiment has the advantage that, in contrast to an upwardly directed bent locking element (6b), by means of the bent locking element (6b) a direct point load is no longer exerted just below the (transparent) top layer (15), as a result of which the risk of damage to the top layer is much less than is the case with upwardly directed locking elements. With upwardly directed locking elements, in the connected position, the pressure exerted by the distal end on the adjacent wall (locking part) may cause damage to the top layer due to the fact that little material is present between the top layer and the contact surface with the distal end of the bent locking element (6b) of an adjacent profiled strip.
[0067] This method according to the invention is also applicable to the connections as illustrated in FIG. 11, where a bent locking element (6b) is produced after milling and bending in the female connecting means and thus not in the male connecting means. By way of example, FIGS. 11a to 11d show the most important steps for bringing about the connection between two adjacent profiled strips by means of their end and/or longitudinal sides. In this case, the sides are provided with hook-shaped connecting means by performing a milling operation.
[0068] The second side is shown in detail in FIG. 11a and comprises a stop face (11) which will produce the connecting area (CS) with an adjacent profiled strip. Next to the stop face (11), a recess is provided which forms a locking groove (14) for the locking element (6b) provided on the first side of an adjacent profiled strip.
[0069] The first side is also subjected to a milling operation in order to produce a projecting lip (6a), as is shown in FIG. 11b. This lip (6a) is then heated locally and bent downwards and temporarily cooled down in order to produce a downwardly directed bent element (6b), as is shown in FIG. 11c, which will form the bent locking element (6b). FIG. 11d shows the connected position of two sides of the profiled strip.
