Method of machining parallel grooves in underside of floor panel

Abstract

According to one method, a floor panel (2) is inserted between a sheet holding transport assembly (7) and a sheet pressing transport assembly (8, 9); the floor panel (2) clamped between the moving sheet-like holding transport assembly (7) and sheet-like pressing transport assemblies (8, 9) performs a feed movement by a linear movement; the cutting heads (10, 11) are rotated about the axes of rotation (X1, X2) and parallel grooves (17, 21, 22) are machined in the lower side (12) of the floor panel (2) using a feed movement imparted to the floor panel (2) by the sheet-like holding transport assembly (7) and the sheet-like pressing transport assembly (8, 9). The machining of the parallel grooves (17, 21, 22) is performed in the lower side (12) of the floor panel (2) by means of a cutting head (10, 11) comprising a set of axially separated profiled disc-shaped cutters having a stepwise varying diameter, when the axes of rotation (X1, X2) of the spindles (23, 24) of the cutting head (10, 11) are inclined at an angle (+ alpha,-alpha) with respect to the plane of the lower side (12) of the floor panel (2) being machined, the cutting head (10, 11) being rotated by the axis of rotation (X1, X2) of the spindles (23, 24) of the cutting head (10, 11) at an angle (+ alpha,-alpha). The machining of the parallel grooves (17, 21, 22) is carried out.

Description

[0001] The subject of the invention is a method for machining parallel grooves in the lower side of a floor panel. The invention can be applied to the production of floor panels made of various materials, in particular wood, wood-based materials, mineral composites or synthetic materials. The formation of grooves in the lower side of the floor panel allows ventilation of the underfloor space and is a prerequisite for a healthy microclimate in the living area, thus ensuring the safety of apartment users who use the panels as flooring. Background Art

[0002] The floor panel known from Polish patent PL 191233 B1 is provided with at least one longitudinal groove which is sufficient for compensating the stresses which occur. Another function of the groove is to provide conditions for air flow to ventilate the underfloor space between the lower side of the floor panel and the floor.

[0003] A method for making a groove in the lower side of a panel element, such as a floor panel or a wall panel made of thermoplastic material and a filler is also known from WO2022050891A1. According to methods known in the art, the shaping of such a thermoplastic floor panel is performed at elevated temperature and the shaped floor panel is subsequently machined using a rotary cutting tool or by planing with a non-rotating tool comprising one or more machining blades.

[0004] A method for making a groove in a floor panel is also known from WO2020180237A1, wherein a machined floor panel is in contact with a supporting element which secures the panel against uncontrolled changes in position. The formation of at least one groove is performed by machining in the lower side of the floor panel using a rotating cutting tool comprising a plurality of blades.

[0005] Purpose of the Invention

[0006] The object of the present invention is to develop a method for producing grooves in the lower side of a floor panel, which method ensures increased efficiency, in particular when simultaneously cutting a plurality of parallel grooves, in particular dovetail, semi-dovetail or parallelogram grooves, wherein the inclined inner wall of each groove extends in a direction from the base of the panel to the interior of the panel. Summary of the invention

[0007] In the method according to the invention, parallel grooves are machined in the lower side of the floor panel using a device having a rotary machining unit in the form of a cutting head. The floor panel is inserted between a sheet holding transport assembly and a sheet pressing transport assembly. The floor panel clamped between the sheet holding transport assembly and the sheet pressing transport assembly is then fed by a linear displacement. The cutting head is subjected to a rotary movement about a rotation axis, after which the parallel grooves are machined in the lower side of the floor panel by means of a sliding movement imparted to the floor panel by the sheet holding transport assembly and by the sheet pressing transport assembly.

[0008] The solution is characterized in that machining of parallel grooves in the underside of the floor panel is performed using a cutting head comprising a set of axially separated profiled disc milling cutters with a stepped diameter variation, wherein machining of the parallel grooves takes place with the axis of rotation of the spindle of the cutting head inclined at an angle relative to the plane of the underside of the machined floor panel.

[0009] Preferably, the floor panel is imparted with a feeding movement by means of a sheet holding transport assembly and a sheet pressing transport assembly using friction sheet elements.

[0010] Preferably, two spaced-apart press-conveyor assemblies are used, wherein at least one cutting head is located between the press-conveyor assemblies.

[0011] Preferably, a stabilizing element in the form of a press shoe is located between the separate press-conveyor assemblies.

[0012] Preferably, a disc-shaped milling cutter is used having an inclined peripheral cutting edge which cuts the bottom of the groove parallel to the plane of the lower side of the floor panel, wherein the inclination angle of the peripheral cutting edge relative to the rotation axis of the cutting head is equal to the inclination angle of the rotation axis of the cutting head relative to the lower side of the machined floor panel.

[0013] Preferably, the disc-shaped milling cutters used are separated by spacers on the spindle of the cutting head.

[0014] Preferably, the milling of the parallel grooves is performed as counter-rotating milling.

[0015] Advantageous Effects of the Invention

[0016] The use of a cutting head comprising a set of axially spaced profiled disc-shaped milling cutters with stepped diameters, using the inclination of the axis of rotation of the main shaft of the cutting head relative to the plane of the lower side of the floor panel to be machined, to machine the parallel grooves ensures fast and efficient machining. This type of milling is more efficient than planing or milling with shank cutters. It allows the use of automated machining lines, providing high-speed feeding of the machined floor panels, wherein the feeding motion is imparted by the holding and pressing transport assemblies.

[0017] Positioning of the cutting head between the spaced apart press transport assemblies ensures stable positioning of the floor panel to be machined on the holding transport assembly, thereby reducing vibrations and improving machining accuracy.

[0018] The use of a disc-shaped milling cutter in which the cutting edge of the bottom of the machined groove is inclined at an angle equal to the inclination of the axis of rotation of the cutting head relative to the plane of the underside of the floor panel to be machined results in the surface of the bottom of the milled groove being parallel to the plane of the underside of the machined floor panel.

[0019] The increased efficiency of cutting dovetail, half dovetail or parallelogram grooves on the underside of the floor panel makes the construction of this type of structure economically justifiable, thereby increasing the possibility of using methods of gluing the floor panel to the floor surface. This additional fixing method is particularly preferred in particular in the case of floor panels made of wood, wood-based materials, mineral composites or synthetic materials, which do not provide sufficient adhesive capacity in their material structure to form a permanent adhesive bond between the underside of the floor panel and the floor.

[0020] The shape of the groove, which in its cross section extends at least unilaterally towards the bottom of the groove, ensures that the adhered floor panel is permanently mechanically connected to the substrate due to the curing of the adhesive filling the shaped groove. When the adhesive fills the groove, the adhesive adapts to the shape of the groove in the floor panel, thereby forming a permanent connection between the floor and the panel. At the same time, the adhesive joint forms a mechanical and chemical bonding connection with the substrate, which is a preferred condition for this panel installation method.

[0021] In the case of snap-on floor installations, the grooves in the lower side of the floor panels also facilitate ventilation of the underfloor space. An additional advantage of using such grooves is that the grooves counteract the effects of possible material stresses in the longitudinal joints of the floor panels that are attached or being attached. Cutting grooves on the lower side of the floor panels in the area of ​​the snap-on elements improves the impact resistance of the material and the bending resistance of the groove lip. It is also worth noting that such panels can be mounted on the floor or wall using flexible metal brackets or other fixing elements. Another important advantage of using such grooves is the reduced weight of the floor panel.

[0022] The method of imparting a feed motion to a floor panel using a sheet-holding transport assembly and a sheet-pressing transport assembly with friction sheet elements prevents the formation of static electricity on the surface of the machined floor panel and thus prevents the unfavorable phenomenon of debris adhering to the machined surface. This method of imparting a feed motion reduces the possibility of damage to the surface of the floor panel being moved due to the reduced possibility of slippage between the panel and the element imparting the feed motion. Thus, the possibility of local heating of the surface of the transported floor panel is eliminated and thus also the possibility of plastic deformation of such heated surface is eliminated.

[0023] Spacing the press-carry assemblies apart allows the cutting head to be positioned between the press-carry assemblies, which increases the accuracy of the groove machining depth.

[0024] A further elimination of vibrations and an increase in the stability of the position of the machined floor panel relative to the cutting head is achieved by positioning a stabilizing element in the form of a press shoe between the separate press-conveyor assemblies.

[0025] The use of spacers between the disc-like milling cutters on the cutting head spindle enables precise spacing between the cutters and therefore the correct distance between the grooves cut in the machined panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The subject matter of the invention is illustrated in an embodiment in the accompanying drawings, in which:

[0027] Figure 1 A method of machining parallel grooves in the underside of a floor panel using a groove cutting device in a vertical format is shown in top view;

[0028] Figure 2a Axonometric view showing a groove cutting device Figure 1 Methods;

[0029] Figure 2b A method of machining parallel grooves in the underside of a floor panel using a groove cutting device in a horizontal form is shown in an axonometric view;

[0030] Figure 3 A method of machining a dovetail groove is shown;

[0031] Figure 4 A method of machining a semi-dovetail groove is shown;

[0032] Figure 5 A method of machining a parallelogram groove is shown;

[0033] Figure 6a shows a cutting head having a spindle inclined at an angle relative to the plane of the underside of the panel;

[0034] Figure 6b It shows that Figure 6a a single cutter shown in a position perpendicular to the plane of the lower side of the panel and a second single cutter inserted into the panel in its working position;

[0035] Figure 6c shows a cross section of a panel having grooves cut in the shape of a parallelogram;

[0036] Figure 7a Shown with Figure 6a an opposing cutting head having a spindle inclined at an angle relative to the plane of the underside of the panel;

[0037] Figure 7b It shows that Figure 7a a single cutter shown in a position perpendicular to the plane of the lower side of the panel and a second single cutter inserted into the panel in its working position;

[0038] Figure 7c shows a cross section of a panel having a groove cut in a dovetail shape;

[0039] Figure 8a shows a cutting head having a spindle arranged parallel to the plane of the underside of the panel;

[0040] Figure 8b It shows that Figure 8a a single cutter shown in a position perpendicular to the plane of the lower side of the panel and a second single cutter inserted into the panel in its working position;

[0041] Figure 8c shows a cross section of a panel having a groove cut in a half dovetail shape;

[0042] Figure 9a A panel with a longitudinally cut groove is shown in an axonometric view;

[0043] Figure 9b shows a cross section of a panel having a groove cut in a downward facing dovetail shape;

[0044] Fig.9c shows a cross section of a panel having a groove cut in a downward facing half dovetail shape;

[0045] Figure 9d shows a cross section of a panel having a groove cut in the shape of a downward facing parallelogram;

[0046] Fig.9e shows that along with Figure 9da cross section of a panel having grooves cut in a downwardly facing parallelogram shape in a direction opposite to the direction of the grooves;

[0047] Fig.10 A cross section of a floor panel assembled from floor panels having longitudinally cut grooves is shown. DETAILED DESCRIPTION

[0048] like Figure 1 As shown in the figure, in a top view, the device 1 for cutting grooves in floor panels 2 comprises in its vertical form a machining assembly comprising two machining units 3, 4 and a stabilizing element in the form of a press shoe 5. The second technical part of the device 1 is a transport assembly comprising horizontal support rollers 6, 6' which hold the transported floor panel 2 in a constant vertical position in the groove cutting device 1, and a sheet holding transport assembly 7 as well as a sheet pressing transport assembly 8 at the inlet of the device 1 and a sheet pressing transport assembly 9 at the outlet of the device 1.

[0049] The transport assembly imparts a linear feed movement to the machined floor panel 2 in a U-shaped direction. The two machining units 3, 4 with the cutting heads 10, 11 mounted thereon are accommodated in the space between the sheet-like pressing transport assemblies 8, 9. The press shoe 5 is fitted behind the cutting head 11. The floor panel 2 is inserted and clamped and fixed in a horizontal plane on the support rollers 6, 6'. During the transport of the floor panel 2 in the device 1, the machining units 3, 4 with the cutting heads 10, 11 mounted thereon perform a working movement on the lower side 12 of the floor panel 2. The press shoe 5 is positioned in the free space between the cutting head 10 and the cutting head 11 and the press shoe 5 presses the machined floor panel 2 against the sheet-like holding transport assembly 7 immediately after the floor panel 2 leaves the working area of ​​the cutting head 10 and before the floor panel 2 enters the working area of ​​the cutting head 11. By applying pressure in this way, the floor panel 2 being moved is reinforced, thus eliminating possible movement deviations during machining, which is a prerequisite for straight-line cutting of regular and repeated groove shapes.

[0050] As in Figure 2aAs shown in FIG, the floor panel 2 is inserted into the device 1 in a vertical position so that the lower side 12 of the core 13 of the floor panel 2 is positioned in front of the cutting heads 10, 11, thereby keeping the edge 14 of the short side of the floor panel 2 perpendicular to the horizontal plane of the support rollers 6, 6'. With the help of the support rollers 6, 6', the floor panel 2 is transported into the operating area of ​​the clamping and feeding system, the base surface of which is the sheet holding transport assembly 7, and the clamping movable pressing side comprises a first sheet pressing transport assembly 8 located at the entrance of the device 1 and a second sheet pressing transport assembly 9 located at the exit of the device 1. The floor panel 2 is clamped between the sheet pressing transport assembly 8 and the sheet pressing transport assembly 9 and is transported into the working area of ​​the first machining unit 3, which automatically enters the working position on the lower side 12 of the floor panel 2. The groove cutting starts automatically when the cutting head 10 is inserted into the core 13 of the floor panel 2 from the lower side 12 of the floor panel 2 at a strictly set distance from the edge 14 of the short side. The initial part of the lower side of the floor panel 2 constitutes a first holding and mounting surface 15, which reaches a boundary line 16 indicating the starting point of machining. From this boundary line 16, the first trajectory of the groove to be cut is formed by the working movement of the cutting head 10 around the rotation axis Y1. Behind the cutting head 10, the floor panel 2 is clamped by the press shoe 5. During the feed movement, the floor panel 2 leaves the working area of ​​the press shoe 5 and moves to the working area of ​​the second tool head 11, which performs a working movement around the rotation axis Y2, giving the final planned shape of the groove 17. After the machining operation, the transported floor panel 2 is taken over by the sheet press transport assembly 9 at the outlet of the device 1 after being displaced beyond the head 11. The sheet-holding transport assembly 7 and the sheet-pressing transport assembly 8, 9 have an integral friction sheet element 18 with anti-slip properties, which has a considerable surface area adhered to the floor panel 2. This configuration of the sheet-pressing transport assembly 8, 9 enables the floor panel 2 to be properly clamped and excludes the possibility of slipping when the floor panel 2 is blocked, thereby ensuring the accuracy of determining the starting point and end point of the groove 17 cutting process.

[0051] exist Figure 2b In the groove cutting device 1 shown in its horizontal form, a floor panel 2 is inserted into the device 1 in a lying position in which the lower side 12 of the floor panel 2 is parallel to the horizontal plane defined by the support rollers 6, 6'. With the help of the support rollers 6, the floor panel 2 is transported into the operating area of ​​the horizontal clamping and feeding system, the fixed side of which includes a sheet holding transport assembly 7 and the movable side consists of a sheet pressing transport assembly 8 at the entrance of the device 1 and a sheet pressing transport assembly 9 at the exit of the device 1.

[0052] The floor panel 2 is clamped between the sheet-holding transport assembly 7 and the sheet-pressing transport assembly 8 located at the entrance of the device and is transported to the working area of ​​the first machining unit 3, which automatically enters the working position in the core 13 of the floor panel 2 on the lower side 12 of the floor panel 2. After receiving the signal that the floor panel 2 has been inserted into the transport assembly, when the cutting head 10 is inserted into the core 13 of the floor panel 2 below the plane of the lower side 12, the cutting of the groove 17 in the panel is automatically started at a strictly set distance from the edge 14 of the short side of the floor panel 2. From the boundary line 16 indicating the starting point of machining, the first step of machining is performed by the working movement of the cutting head 10 around the rotation axis X1. Behind the cutting head 10, the floor panel 2 is clamped by the pressing shoe 5, which presses the floor panel 2 downwards while allowing the floor panel 2 to move together with the sheet-holding transport assembly 7. During the feeding movement, the floor panel 2 leaves the working area of ​​the press shoe 5 and moves to the working area of ​​the second machining unit 4, which is brought into working position in the core 13 of the floor panel 2, similarly to the first machining unit 3, on the lower side 12 of the floor panel 2. After the second step of machining, the cutting head 11, which performs a working movement around the axis of rotation X2, gives the final planned shape of the profile to be machined. On the lower side 12 of the floor panel 2, the area without grooves is a first lower holding and mounting surface 15, which is contained between the edge 14 of the short side and the boundary line 16 indicating the start of machining. The sheet holding transport assembly 7 and the sheet pressing transport assembly 8, 9 have built-in friction sheet elements 18 with anti-slip properties on the contact surface associated with the floor panel 2. Such transport assemblies prevent slipping, thereby ensuring that the floor panel 2 is correctly positioned and that the start and end of the machining process are accurate relative to the edge 14 of the short side and relative to the second edge 19 of the short side.

[0053] like Figure 3, the floor panel 2 is horizontally placed with its top side 20 on the sheet-shaped holding and transporting assembly 7. Before the longitudinal grooves 21, 22 are machined, locking profiles in the form of mounting tongues 25 and mounting grooves 26 can be produced on the longitudinal edges of the floor panel 2 by means of cutting heads 10, 11 mounted on spindles 23, 24. The first cutting head 10 mounted on the first spindle 23 rotates together with the spindle about the axis of rotation X1 of the spindle, which is inclined at a positive angle +α relative to the plane of the floor panel 2, wherein the direction of machining is opposite to the direction of feed. The cutting head 10 is inserted into the core 13 at a strictly set distance from the edge 14 of the short side and cuts the groove 21. The position at which the cutting head 10 is inserted into the core 13 of the floor panel 2 is the boundary line 16, which indicates the starting point of machining the longitudinal groove 21 in the shape of a parallelogram. The second cutting head 11 mounted on the second spindle 24 rotates around the rotation axis X2 of the spindle inclined at a negative angle -α relative to the plane of the floor panel 2 while maintaining the reverse rotation direction of machining, and makes complementary cuts in the groove 21, thereby determining the final shape of the groove 22. The area without cut grooves 21, 22 contained between the edge 14 of the short side and the boundary line 16 indicating the starting point of machining constitutes the first lower holding and mounting surface 15. The cutting head 10 and the cutting head 11 that produce the grooves 21, 22 end their working movement at a planned distance in front of the edge 19 of the short side, and the cutting heads 10, 11 automatically withdraw from the core 13 of the machined floor panel 2 together with the spindles 23, 24. The cutting of the grooves 21, 22 in the panels 2 transported in sequence is performed in a similar manner. After machining with the two cutting heads 10, 11, the groove 22 has a dovetail shape in cross section, i.e., an isosceles trapezoid.

[0054] exist Figure 4 In another embodiment shown in FIG, grooves 21, 28 are machined in the floor panel 2 on the lower side 12 of the floor panel 2 visible in the drawing by means of a cutting head 10, 27. During the groove cutting process, the floor panel 2 is placed horizontally with its top side 20 on the sheet-shaped holding and transporting assembly 7. Figure 3In the example shown in , locking profiles in the form of mounting tongues 25 and mounting grooves 26 can be produced on the longitudinal edges of the floor panel 2 before the longitudinal grooves 21, 28 are machined. The first cutting head 10 mounted on the spindle 23 rotates around the axis of rotation X1 of the spindle 23, which is inclined at a positive angle +α relative to the plane of the floor panel 2, wherein the machining direction is opposite to the feed direction. The cutting head 10 is inserted into the core 13 at a strictly set distance from the edge 14 of the short side and cuts the groove 21. The position at which the cutting head 10 is inserted into the core 13 of the floor panel 2 is the starting point for cutting the groove 21, the cross section of which has a parallelogram shape. The machining tools mounted on the cutting head 10 have variable diameters. At the same time, the machining tools mounted on the spindle 24 of the cutting head 27 have equal machining radii and are mounted in a horizontal position parallel to the lower side 12 of the floor panel 2. During the working movement, the cutting head 27 rotates together with the spindle 24 about the axis of rotation X3 of the spindle 24 in a counter-rotating machining direction, thereby making a complementary cut in the previously cut groove 21, establishing the final cross-sectional shape of the groove 28 in the form of a half dovetail, i.e. a rectangular trapezoid. The area without cut grooves contained between the edge 14 of the short side and the boundary line 16 indicating the start of machining constitutes the first lower holding and mounting surface 15. The cutting heads 10 and 27 that produced the grooves 21, 28 end their working movement at a predetermined distance in front of the edge 19 of the short side, and then withdraw these cutting heads from the machined floor panel 2.

[0055] exist Figure 5In another embodiment shown in FIG. 1 , a method is shown for cutting a groove 21 in the core 13 of a floor panel 2 on the visible lower side 12 of the floor panel 2 by means of a cutting head 10. While the groove 21 is being cut, the floor panel 2 is placed horizontally with its top side 20 on the sheet transport assembly 7. Before the groove 21 is cut, locking contours in the form of mounting tongues 25 and mounting grooves 26 are produced on the longitudinal edges of the floor panel 2. The cutting head 10, mounted on a spindle 23, rotates about the axis of rotation X1 of the spindle 23, which is inclined at a positive angle +α relative to the horizontal of the floor panel 2, wherein the machining direction is opposite to the feed movement direction. The cutting head 10 is inserted into the core 13 of the floor panel 2 at a strictly set distance from the edge 14 of the short side and cuts a groove 21 with a parallelogram cross section. The area without the cut groove contained between the edge 14 of the short side and the boundary line 16 indicating the start of machining constitutes the first lower holding and mounting surface 15. The milling cutter 29 with cutting teeth 30 mounted on the cutting head 10 has a variable diameter, which is a prerequisite for obtaining a groove 21, wherein the wall of the groove 21 is inclined relative to the plane of the lower side 12 of the floor panel 2. The area without the cut groove 21 contained between the edge 14 of the short side and the boundary line 16 indicating the starting point of machining constitutes the first lower holding and mounting surface 15. The cutting head 10 automatically withdraws from the floor panel 2 at a predetermined distance in front of the edge 19 of the short side in the last step of cutting the groove 21. The groove 21 has a parallelogram-shaped cross section after cutting using one cutting head 10. At the same time, the spindle 24 does not participate in the groove cutting and is in a standby state.

[0056] exist Figure 6a The complete cutting head 10 is shown in the embodiment in FIG. 1 . The cutting head 10 has a mounting sleeve 31 with a spacer 32 mounted on a spindle 23. The machining tool mounted on the cutting head 10 has the form of cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 with diameters D1, D2, D3, D4, D5, D6, D7 that vary gradually in the range of 150 mm to 210 mm. The thickness of the spacer 32 determines the distance between adjacent edges of the grooves 21 cut in the core 13 of the lower side 12 of the floor panel 2. The spindle 23 on which the cutting head 10 is mounted has its rotation axis X1 inclined at a positive angle +α relative to the plane of the lower side 12 of the machined floor panel 2.

[0057] The cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 with gradually changing diameters D1, D2, D3, D4, D5, D6, D7 have a disc-shaped body 34 with teeth 35 having a peripheral cutting edge 36 inclined at an angle α, such as Figure 6b , whereby the peripheral cutting edge 36 remains parallel to the plane of the lower side 12 of the floor panel 2 at the point of contact with the lower side 12 of the floor panel 2. With this configuration, the cutting head 10 machines a groove 21 having a parallelogram-shaped cross section.

[0058] exist Figure 6b In the Figure 6a A schematic illustration of a single machining tool in the form of a cutter 33.1 in the cutting head 10 shown in FIG. Figure 6b The left side in the figure shows the disc-shaped body 34 of the cutter 33.1 in a position perpendicular to the plane of the lower side 12 of the floor panel 2. The right side shows the correct working position of the body 34 of the cutter 33.1. Each tooth 35 has a peripheral cutting edge 36 and two lateral cutting edges 37, 38, whereby an ellipse of radius r1 is formed at the intersection of the lateral cutting edge 38 with the peripheral cutting edge 36. Figure 6a The teeth 35 of the cutter 33.1 shown in the figure and the teeth 35 of the other cutters 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 have machined blades with a single right bevel cut at an angle α. The cutters in the working position are inserted into the core 13 from the lower side 12 of the floor panel 2.

[0059] exist Figure 6c It is shown in Figure 6a 2. The shape of the groove 21 cut by the cutting head 10 on the lower side 12 in the core 13 of the floor panel 2 is shown in FIG. The groove has a parallelogram-shaped cross section after being cut using the cutting head 10.

[0060] Figure 7aThe complete cutting head 11 is shown in the embodiment in FIG. 1 . The cutting head 11 has a mounting sleeve 31 with a spacer 32 mounted on a spindle 24. The machining tools mounted on the cutting head 11 are in the form of cutters 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7 with diameters D1, D2, D3, D4, D5, D6, D7 that vary gradually in the range of 150 mm to 210 mm and are mounted on the mounting sleeve and separated by spacers 32, the thickness of which determines the distance between adjacent edges of the cutting grooves 22 in the core 13 of the lower side 12 of the floor panel 2. The spindle 24 on which the cutting head 11 is mounted has its rotation axis X2 inclined at a negative angle -α relative to the plane of the lower side 12 of the machined floor panel 2.

[0061] The cutters 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7 with gradually varying diameters D1, D2, D3, D4, D5, D6, D7 have a disc-shaped body 34 with teeth 40 having a peripheral cutting edge 41 inclined at an angle α, such as Figure 7b , whereby these peripheral cutting edges 41 remain parallel to the lower side 12 of the floor panel 2 at the point of contact with the lower side 12 due to the main axis being inclined at a negative angle -α, the floor panel 2 faces the lower side with its top side 20. With this configuration, the cutting head 11 machines a groove 22 having a parallelogram cross section.

[0062] exist Figure 7b In the Figure 7a A schematic illustration of a single machining tool in the form of a cutter 39.1 in the cutting head 11 shown in FIG. Figure 7b The left side in the figure shows the disc-shaped body 34 of the cutter 39.1 in a position perpendicular to the lower side 12 of the floor panel 2. The right side shows the correct working position of the cutter 39.1, wherein the cutter 39.1 is inclined at an angle of 90-α relative to the lower side 12 of the floor panel 2. The same inclination of the cutter 39.1 relative to the lower surface of the cutting groove 21 occurs, since this lower surface of the groove 21 is parallel to the lower side 12 of the floor panel 2. Each tooth 40 has a peripheral cutting edge 41 and two lateral cutting edges 42, 43, whereby an ellipse of radius r1' is formed at the intersection of the lateral cutting edge 42 with the peripheral cutting edge 41. Figure 7aThe teeth 40 of the cutter 39.1 shown in the drawing and the teeth 40 of the other cutters 39.2, 39.3, 39.4, 39.5, 39.6, 39.7 have a machined blade with a single-sided left-bevel cut inclined at an angle α. The cutter 39.1 in the working position is inserted into the core 13 from the lower side 12 of the floor panel 2 in order to give the final shape to the previously cut groove 21. The second lateral cutting edge 43 of the tooth 40 does not participate in the machining. The cross section of the groove 22 milled by the two cutting heads 10 and 11 has the shape of an isosceles trapezoid.

[0063] exist Figure 7c It is shown in Figure 6a and Figure 7a The shape of the groove 22 cut by the cutting head 10 and the cutting head 11 illustrated in FIG. 2 in the core 13 on the lower side 12 of the floor panel 2. The groove 22 cut using these cutting heads 10, 11 has a cross-sectional shape of an isosceles trapezoid.

[0064] exist Figure 8a The cutting head 27 shown in the embodiment of FIG. 2 has a mounting sleeve 31 with a spacer 32 mounted on the spindle 24. The machining tool mounted on the cutting head 27 is in the form of a cutter 44 of constant diameter D=210 mm. The cutters 44 are mounted in the mounting sleeve 31 and are separated by the spacer 32, the thickness of which determines the distance between adjacent edges of the cutting grooves 28 in the core 13 of the lower side 12 of the floor panel 2. The axis of rotation X3 of the spindle 24, on which the cutting head 27 is mounted, is parallel to the plane of the lower side 12 of the floor panel 2. As shown in FIG. Figure 8b As shown in FIG. 4 , the teeth 45 of the cutter 44 have straight cuts and a rectangular shape.

[0065] Figure 8b Shown sitting in Figure 8a A single machining tool in the form of a cutter 44 in the cutting head 27 is shown in FIG. Figure 8bThe left side of the figure shows the disc-shaped body 34 of the cutter 44 in a position in contact with the lower side 12 of the floor panel 2. The working position of the cutter 44 is shown on the right side, in which the cutter 44 is inserted into the groove 21. Once the cutter 44 passes, the groove 21 takes the form of the groove 28. Each tooth 45 of the cutter 44 has a peripheral cutting edge 46 and two lateral cutting edges 47, 48, whereby an ellipse with radii r1', r1 is formed at the intersection of the lateral cutting edges 47, 48 with the peripheral cutting edge 46. The teeth 45 of the cutter 44 are rectangular in shape. The cutter 44 in the working position is inserted into the core 13 from the lower side 12 of the floor panel 2 so as to make a rectangular cut of the groove 28. In this case, the second lateral cutting edge 48 of the tooth 44 does not participate in the machining. The cross section of the groove 28 milled by the two cutting heads 10 and 27 has a rectangular trapezoidal shape.

[0066] exist Figure 8c 2 shows a floor panel 2 having a groove 28 cut in one working pass in the device 1 by means of two cutting heads 10 and 27. The groove 28 has a cross-sectional shape of a rectangular trapezoid and is cut in the core 13 on the lower side 12 of the floor panel 2.

[0067] Figure 9a The floor panel 2 is shown with its top side 20 facing downwards, the floor panel 2 having a longitudinal groove 22 cut in the core 13 on the visible lower side 12 of the floor panel 2, as shown in FIG. Figure 7c The grooves 22 have a cross-sectional shape of an isosceles trapezoid. Between the boundary line 16 indicating the machining start point of the groove 22 and the edge 14 of the first short side portion, an uncut area covering an area having a length L1 is formed, which is the first lower holding and mounting surface 15 of the floor panel 2. The boundary line 49 indicating the machining end point of the groove 22 is separated from the edge 19 of the second short side portion, and thus defines a second uncut area of ​​length L1', which is the second holding and mounting surface 50.

[0068] Figure 9b , a floor panel 2 having a groove cut in a dovetail shape is shown, wherein the top side 20 of the floor panel 2 faces upward. The cut groove 22 is an isosceles trapezoidal shape, and the cut groove 22 has: a right side wall 51, which has a positive inclination angle +α; and a left side wall 52, which has a negative inclination angle -α. The bottom 53 of the groove 22 has an ellipse with radii r1', r1 at the point of contact with the side walls 51 and 52 of the groove 22, thereby increasing the bending strength of the floor panel 2. The cut groove 22 has an outer width S1, an inner width S2 and a groove height h. The outer spacing S3 between the side walls 51 and 52 of adjacent grooves 22 is: S3≥1.5×S1. In Figure 9b In the embodiment shown in , for a floor panel with a thickness of 6 mm, the dimensional parameters ensuring sufficient strength of the floor panel under typical use are: α=±9°; S1=4 mm; S2=5 mm; S3=6 mm; h=3 mm.

[0069] exist Fig.9c , a floor panel 2 having a groove cut in a semi-dovetail shape is shown, wherein the top side 20 of the floor panel 2 faces upward. The cut groove 22 has a rectangular trapezoidal cross-sectional shape having a vertical side wall 54 and a left side wall 52 with a negative inclination angle -α. The bottom 55 of the groove has an elliptical shape with radii r1, r1' at the contact with the side walls 54 and 52 of the groove, thereby increasing the bending strength of the floor panel 2. The cut groove 28 has an outer width S4, an inner width S5 and a height h. The interval S6 between the side walls 54 and 52 of adjacent grooves 28 is: S6 ≥ 1.5×S4. In Fig.9c In the embodiment shown in , for a floor panel 2 having a thickness of 6 mm, the dimensional parameters ensuring sufficient strength of the floor panel 2 under typical use are: α=-9°; S4=4.5 mm; S5=5 mm; S6=7 mm; h=3 mm.

[0070] Figure 9d A floor panel 2 is shown, wherein the top side 20 of the floor panel 2 faces upward. On the lower side 12 in the core 13 of the floor panel 2, there is a groove 21 cut in a parallelogram cross-sectional shape, the groove 21 having a left side wall 52 and a right side wall 56 with a negative inclination angle -α. With the inclination angle -α being equal, the side wall 52 and the side wall 56 remain parallel to each other. The bottom 57 of the groove has an elliptical shape with a radius r1 at the point of contact with the side wall 52, thereby increasing the bending strength of the floor panel 2. The cut groove has an outer width S7, an inner width S8 and a groove height h, wherein S7=S8. The spacing S9 between the side walls of adjacent grooves 21 is: S9≥1.5×S7. Figure 9d In the embodiment shown in , for a floor panel 2 having a thickness of 6 mm, the dimensional parameters ensuring sufficient strength of the floor panel 2 under typical use are: α=-9°; S7=3.5 mm; S8=3.5 mm; S9=6 mm; h=3 mm.

[0071] Fig.9e shows that along with Figure 9d For a floor panel 2 having a thickness of 6 mm, the dimensional parameters ensuring sufficient strength of the floor panel 2 under typical use are: α=+9°; S7=3.5 mm; S8=3.5 mm; S9=6 mm; h=3 mm.

[0072] Fig.10 A floor panel 2 is shown installed on a floor by gluing to a flooring 58. There is an adhesive joint 59 between the flooring 58 and the laid floor panel 2, while the contour of the groove 22 is filled with a cured adhesive compound in the form of adhesive fins 60, mimicking the shape of the groove 22. This results in a mechanical connection between the floor panel 2 and the dovetail flooring, wherein the expanded and cured adhesive fins 60 form a joint with the cut groove 22, thereby increasing the positional stability of the floor panel 2 relative to the flooring 58.

[0073] The machining method according to this embodiment can be performed by means of Figure 1 and Figure 2a The device 1 shown in its vertical form is implemented, or by means of Figure 2b , Figure 3 , Figure 4 , Figure 5 , Figure 6a , Figure 7a , Figure 8a The device 1 is shown in its horizontal form. The device 1 has a transport assembly with horizontal support rollers 6, 6', a sheet holding transport assembly 7, a sheet pressing transport assembly 8 at the inlet of the device 1 and a second sheet pressing transport assembly 9 at the outlet of the device 1. There is also a machining assembly with two independent machining units 3, 4, which are built into the structure of the device 1 in the form of cutting heads 10, 11. In the space between the cutting heads 10, 11, a pressure shoe 5 is built, which presses the machined floor panel 2 against the sheet holding transport assembly 7, so that a linear transport path is maintained during machining. The machining units 3, 4 have an adjustable distance and angular position relative to the lower side 12 of the floor panel 2, so that for the horizontal form of the device 1, the inclination angle +α, -α of the rotation axis X1, X2 of the spindle 23, 24 of the cutting head 10, 11 or for the vertical form of the device 1, the inclination of the rotation axis Y1, Y2 can be set. Angular adjustment of the position of the units 3, 4 is a necessary condition for achieving the purpose of the method according to the invention. By giving the axes of rotation X1, X2, Y1, Y2 of the spindles of the cutting heads 10, 11 an inclination angle α, parallel grooves 17, 21, 22 are obtained in the lower side 12 of the floor panel 2, wherein the side walls 51, 52, 56 are inclined at the same angles +α, -α relative to the plane of the lower side 12, as Figure 9b , Fig.9c and Figure 9d As shown in .

[0074] In an embodiment according to the invention, the cut parallel grooves 17, 21, 22, 28 have bottoms 53, 55, 57 parallel to the plane of the lower side 12 of the floor panel 2. Figure 6b , Figure 7b As schematically shown in FIG, this feature is achieved by tilting the peripheral cutting edges 36, 41 of the teeth 35, 40 engaged with the disc-shaped body 34 at an angle α so that these peripheral cutting edges 36, 41 remain parallel to the plane of the lower side 12 of the floor panel 2 at the point of contact with the lower side 12 of the floor panel.

[0075] exist Figure 1 and Figure 2a The cutting of parallel grooves 17, 21, 22, 28 in the lower side 12 of the floor panel 2 arranged vertically is shown in FIG. Figure 2b , Figure 3 , Figure 4 , Figure 5 , Figure 6a , Figure 7a , Figure 8a The cutting of parallel grooves arranged horizontally is shown in FIG.

[0076] In a first step, the floor panel 2 is inserted between the sheet holding transport assembly 7 and the sheet pressing transport assembly 8, 9. The floor panel 2 clamped between the sheet holding transport assembly 7 and the sheet pressing transport assembly 8, 9 then undergoes a feed movement by a linear movement. For this purpose, a friction sheet element 18 with anti-slip properties is used to counteract the blocking of the floor panel 2 during the feed movement and any deviation from the linear feed direction. The cutting head 10, 11, 27 undergoes a rotational movement about the rotation axis X1, X2, Y1, Y2 and machines parallel grooves 17, 21, 22, 28 in the lower side 12 of the floor panel using the feed movement imparted to the floor panel by the sheet holding transport assembly 7 and the sheet pressing transport assembly 8, 9.

[0077] The simultaneous machining of a plurality of parallel grooves 17, 21, 22, 28 in the lower side 12 of the floor panel 2 is performed using a cutting head 10, 11, 27, which comprises a Figure 6a The axially separated special-shaped disc cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 shown in the figure or the like Figure 7a The disc cutters 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7 shown in FIG. The disc cutters have gradually changing diameters D1, D2, D3, D4, D5, D6, D7, whereby, as shown Figure 6a In the case where the axis of rotation X1, Y1 of the spindle 23 of the cutting head 10 is inclined at an angle +α relative to the lower side 12 of the machined floor panel 2, or as shown in Figure 7aAs shown in , the machining of the parallel grooves 17 , 21 , 22 is performed with the rotation axis X2 , Y2 of the spindle 24 of the cutting head 11 tilted at an angle −α relative to the lower side 12 of the machined floor panel 2 .

[0078] In an embodiment of the method of machining parallel grooves in the lower side of a floor panel 2 using the groove cutting device in its vertical form, as shown in FIG. Figure 1 and Figure 1 As shown in a, the machining units 3, 4 and the sheet pressing and transporting assemblies 8, 9 are positioned in a vertical plane. Furthermore, the machined floor panel 2 is placed vertically with the wide plane of its lower side 12. The edges of the long sides of the transported floor panel 2 rest on support rollers 6, 6' positioned horizontally in the device 1. The cutting head 10 performs a rotational movement around the rotation axis Y1 and the cutting head 11 performs a rotational movement around the rotation axis Y2, the machining direction being opposite to the feed direction of the panel 2. The vertical form of the device 1 is a compact structure made of similar components to the horizontal form of the device 1, having the same operating principle and implementation of the machining operation on the floor panel 2. In an embodiment of the method for machining parallel grooves in the lower side of the floor panel 2 using the groove cutting device in its horizontal form, as Figure 2b and Figure 3 As shown in FIG. 1 , the cutting heads 10 and 11 perform a rotational movement about the axis X1 and the axis X2 , wherein the machining direction is opposite to the feed direction of the transported floor panel 2 .

[0079] like Figure 2b As shown in , the moving floor panel 2 enters the working area of ​​the press shoe 5 after passing through the working area of ​​the cutting heads 10 and 11, and the press shoe 5 applies pressure to the lower side 12 of the floor panel 2, thereby pressing the floor panel 2 against the base, which is the sheet-holding and transporting component 7. The transported floor panel 2 moves directly from the working area of ​​the press shoe 5 to the working area of ​​the second machining unit 4 on which the cutting head 11 is installed, and the cutting head 11 performs a rotational movement around the rotation axis X2, thereby widening the groove 17 previously cut by the cutting head 10 so that the groove 17 has the desired size and cross-sectional shape. After cutting the groove 17, the moving floor panel 2 enters the area of ​​the sheet-pressing and transporting component 9, which presses the machined floor panel 2 against the sheet-holding and transporting component 7, thereby moving the floor panel 2 toward the exit side of the device 1 through the horizontally received support rollers 6'. As shown Figure 9a As shown in FIG. 1 , a region without the cut groove 22 included between the edge 14 of the short side portion and the boundary line 16 indicating the start point of the groove cutting constitutes the first lower holding and mounting surface 15 .

[0080] The cutting head 10, 11 or 27 comprises a sleeve 31 with seated profiled disc cutters 29, 33.1 to 33.7, 39.1 to 39.7, 44 separated by spacers 32, which adjust the spacing between the cutters and thus the distance between the cutting grooves 17, 21, 22, 28 in the machined floor panel. Each profiled disc cutter set at an inclination angle +α, -α in the cutting head 10 or cutting head 11, respectively, has a diameter that gradually changes from D1 to D7. Therefore, each of the cutters in the cutting head 10 and the cutting head 11 has a different machining speed and can have a different number of machining blades. A common parameter for machining the cutter assembly is the thickness of the machining layer.

[0081] The structure of the device 1 for cutting grooves 17, 21, 22, 28 allows the individual cutting heads 10, 11 or 27 to be mounted so that the angle of inclination α of the cutting heads 10, 11 or 27 relative to the plane of the machined panel can be adjusted. The cutting heads 10 and 11 have cutters with a variable diameter D, while the cutting head 27 comprises a cutter with a uniform diameter D and is used to shape the groove 28 to have a cross section of a rectangular trapezoid, wherein the groove 21 was previously cut using the cutting head 10. The machining assembly of the cutting heads 10 and 11 shapes the groove 22 to have a cross section of an isosceles trapezoid, which is also called dovetail type, while the groove 21 is shaped to have a parallelogram cross section using a single cutting head 10 or 11 during the machining process.

[0082] Example

[0083] Example 1 - Machine a groove with an isosceles trapezoidal shape

[0084] like Figure 1 , Figure 2a , Figure 2b and Figure 3 The groove shown in FIG. 1 , which has an isosceles trapezoidal shape, also known as a dovetail type, is made using two machining units 3 , 4 equipped with a cutting head 10 and a cutting head 11 . For this purpose, a Figure 6a , which is equipped with a set of cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 with variable diameters D1, D2, D3, D4, D5, D6, D7, which are mounted on a spindle 23 inclined at an angle +α relative to the plane of the sheet-holding transport assembly 7 and at the same time relative to the plane of the lower side 12 of the floor panel 2. Thus, as Figure 6c As shown, a plurality of parallel grooves 21 having a parallelogram-shaped cross section are cut.

[0085] Then, use Figure 7a, the cutting head 11 shown in the drawing is equipped with a set of cutters 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7 with variable diameters D1, D2, D3, D4, D5, D6, D7, which are mounted on a spindle 24 which is inclined at an angle -α relative to the plane of the sheet-holding transport assembly 7 and at the same time relative to the plane of the lower side 12 of the floor panel 2. Thus, as Figure 7c and Figure 9b As shown in FIG. 2 , a groove 22 is cut which is complementary to the previously made groove 21. This complementary groove 22 has the shape of an isosceles trapezoid.

[0086] The inner width S2 of the bottom of each groove 22 is greater than its outer width S1 on the lower side 12 of the floor panel 2. The height h of the cut groove is adjusted by the insertion size of the two machining units 3 and 4.

[0087] Example 2 - Machining a Rectangular Trapezoidal Shape Groove

[0088] like Figure 1 , Figure 2a , Figure 2b and Figure 4 The rectangular trapezoidal shape, also known as the semi-dovetail type groove shown in FIG. 1 , is made using two machining units 3 , 4 equipped with cutting heads 10 and 27 . First, using Figure 6a , which is equipped with a set of cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 with variable diameters D1, D2, D3, D4, D5, D6, D7, which are mounted on a spindle 23 inclined at an angle +α relative to the plane of the sheet-holding transport assembly 7 and at the same time relative to the plane of the lower side 12 of the floor panel 2. Thus, as Figure 6c As shown in FIG. 1 , a plurality of parallel grooves 21 having a parallelogram-shaped cross section are cut.

[0089] Then, use the Figure 8a The machining unit 4 of the cutting head 27 shown in FIG. 4 forms the final shape of the groove 28 by means of the uniform diameter D of the cutter 44 and the horizontal position of the axis of rotation X3 of the spindle 24, as shown in FIG. Figure 8c and Fig.9c The side wall 54 of the groove 28 thus formed is perpendicular to the plane of the lower side 12 of the floor panel 2 and the bottom 55 of the cut groove 28. The inner width S5 of the bottom 55 of the groove 28 is greater than the outer width S4 of the groove 28 cut on the plane of the lower side 12 of the floor panel 2. Similar to Example 1, the height h of the cut groove is adjusted by the insertion size of the two machining units 3, 4.

[0090] Example 3 - Machining a parallelogram-shaped groove

[0091] The parallelogram-shaped groove 21 is made by means of the first machining unit 3 equipped with the cutting head 10. Figure 6c and Figure 9d The outer width S7 of the groove 21 shown in the figure is equal to the inner width S8 of the groove 21, and the side walls 52, 56 of the groove 21 have the same inclination angle -α relative to the plane of the bottom 57 and the plane of the lower side 12 of the floor panel 2. The height h of the cut groove is adjusted by the insertion size of the machining unit 3 relative to the lower side 12 of the floor panel 2.

[0092] When the groove is cut using the cutting head 11 without involving the machining unit 3 by using the second machining unit 4 equipped with the cutting head 11, a groove 21 having a parallelogram cross section is obtained, wherein the width S7 and the width S8 of the groove 21 are equal, and the inclination angle of the side walls 52a, 51 of the groove 21 is +α, as shown in Fig.9e As shown in ,.

[0093] In an alternative embodiment of the solution according to the invention, a mounting tongue 25 is cut on one of the long sides of the floor panel 2 and a mounting groove 26 is cut on the other long side before cutting the grooves 17, 21, 22, 28. The grooves 17, 21, 22, 28 cut next are parallel to the profile of the mounting tongue 25 and the mounting groove 26 on the long sides of the floor panel 2.

[0094] The grooves 17, 21, 22, 28 are cut using different forms of cutting heads 10, 11, 27. The complete cutting head 10 comprises a mounting sleeve 31 having a spacer 32 on which the machining tool is mounted. The thickness of the spacer 32 determines the distance between adjacent edges of the cut grooves 17, 21, 22, 28.

[0095] The cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 of a cutting head 10 with a gradually changing diameter D1, D2, D3, D4, D5, D6, D7 have teeth 35 built into the periphery of the body 34, wherein in each consecutive cutter from the group of cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 the diameter is reduced and the number of built-in teeth 35 is adjusted, which number determines a similar thickness of the layer machined by the teeth 35, regardless of the cutter diameter.

[0096] A similar principle applies to the use of a cutting head 11 with a mounting sleeve 31 and a spacer 32, the cutting head 11 being equipped with a machining tool in the form of a cutter 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7 with a gradually changing diameter D1, D2, D3, D4, D5, D6, D7. Here, too, the diameter is reduced and the number of built-in teeth 40 is adjusted, which determines a similar thickness of the layer machined by the teeth 40, regardless of the cutter diameter.

[0097] like Figure 2b and Figure 3 As shown in , the process of cutting the grooves 21, 22 in the floor panel 2 starts with inserting the floor panel 2 into the working area of ​​the machining unit 3 on which the cutting head 10 is mounted. The working surface of the cutting head 10 is positioned in a horizontal plane just above the sheet-holding transport assembly 7, the height of the gap between the sheet-holding transport assembly 7 and the working surface of the cutting head being 1 mm greater than the thickness of the machined floor panel 2. After the edge 14 of the short side of the floor panel 2 has passed through the axis X1 of the spindle 23 of the machining unit 3, the unit is inserted towards the lower side 12 of the floor panel 2, wherein the teeth 35 of the cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 are inserted in the core 13 to a depth corresponding to the height h of the cut grooves 21, 22, thereby starting the cutting of these grooves from the boundary line 16, establishing the length L1 of the first lower holding and mounting surface, as shown in FIG. Figure 9a The transported floor panel 2 performing the feed movement just behind the cutting head 10 is pressed against the base sheet holding transport assembly 7 using the press shoe 5, thus ensuring the correct positioning of the moved floor panel 2 and creating conditions for cutting the grooves 21 of repeated shape along the predetermined length of the floor panel 2.

[0098] The floor panel 2 is then moved from the press shoe 5 to the working area of ​​the machining unit 4, where the mounted cutting head 11 is located on the sheet holding transport assembly 7. After the edge 14 of the short side of the floor panel 2 has passed through the axis X2 of the spindle 24, the machining unit 4 is moved towards the lower side 12 of the floor panel 2 and the teeth 40 of the cutters 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7 are moved in parallel to the cutting groove 21 in the core 13, so that the groove 22 has the final shape of an isosceles trapezoidal cross section. The cutting of the grooves 21 and 22 is performed simultaneously until the length of the cutting groove 21 in the core 13 of the floor panel 2 is reached. The machining unit 3 with the cutting head 10 is then automatically withdrawn from the core 13 of the floor panel 2, thereby establishing a boundary line 49 at the point where the machining is terminated, which indicates the end of the machining and then returns to the starting position 1 mm above the lower side 12 of the floor panel 2. In the starting position, the working planes of the cutters 33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7 of the cutting head 10 are at a height of 1 mm above the lower side 12 of the floor panel 2 and the floor panel 2 performs a feed movement and continues to cut parallel grooves 22 in the core 13 of the floor panel 2 by the cutting head 11 until a boundary line 49 indicating the end of machining is reached. Then, the machining unit 4 with the cutting head 11 automatically withdraws from the core 13 of the floor panel 2, thereby presenting a starting position in which the working planes of the cutters 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7 are at a height of 1 mm above the lower side of the floor panel 2.

[0099] like Figure 9a The surface without grooves on the lower side 12 of the floor panel 2 included between the boundary line 49 indicating the end of machining and the edge of the short side of the length L1', as shown in FIG. 1 , constitutes the second holding and mounting surface 50. The working sequence for cutting the grooves 22 of the floor panel 2 is continuously performed by the machining units 3, 4 in the device 1 at a feed speed of up to 200 m / min. The presentation of the working position and the rest position of the machining units 3 and 4 in the core 13 of the floor panel 2 is performed by means of a servo mechanism.

[0100] The movement of the floor panel 2 during the groove cutting is performed together with the sheet holding transport assembly 7 and the sheet pressing transport assembly 8, 9 of the device 1. The device 1 can be made in vertical form or in horizontal form. The choice of the structural solution depends on the environment and local conditions of the manufacturing facility.

[0101] Preferably, the vertical arrangement of the feeding and machining assemblies is particularly designed to carry out the cutting of grooves 21, 22, 28 in the core 13 of a floor panel 2 made of synthetic material, rock composites with plasticizers and binders or other plastic agglomerates with electrostatic properties, which hinder the discharge of the debris formed during the cutting of the grooves and cause the debris to be deposited on the outer surface of the panel.

[0102] The friction sheet elements 18 are made of a material with anti-slip properties and form the outer contact sides of the transport components 7, 8, 9 of the device 1. These friction sheet elements 18 contact the machined floor panel 2 on the holding side and the pressing side, thereby adhering to a larger area of ​​the transported and machined floor panel 2. In addition, the friction sheet elements 18 on the sides of the sheet-holding transport component 7 and on the sides of the sheet-pressing transport components 8, 9 have independent synchronous drive devices. The machined floor panel 2 is clamped between the friction sheet elements 18 of the sheet-holding transport component 7 and the friction sheet elements 18 of the sheet-pressing transport components 8, 9 and performs a linear movement in the device 1 according to the feed direction. The release of the clamping of the floor panel 2 occurs on the outlet side of the device 1. This transport solution for the machined floor panel 2 provides the advantage that the traction force caused by friction is greater than the actual feed force, which is a prerequisite for using linear feed speeds >100 m / min, which excludes slipping of the machined floor panel 2 in the clamping and feed system of the device 1.

[0103] The method of imparting feed motion to the machined floor panel 2 by clamping and moving the machined floor panel 2 between the friction sheet elements 18 of the sheet holding transport assembly 7 and the friction sheet elements 18 of the sheet pressing transport assembly 8, 9 has important technical advantages compared to the commonly used transport system based on drive rollers with limited contact with the machined object being moved.

[0104] Reference numerals list

[0105] 1 Groove cutting device

[0106] 2 Floor Panels

[0107] 3 Machining units

[0108] 4 Machining units

[0109] 5. Press Shoes

[0110] 6, 6' support roller

[0111] 7-sheet holding transport assembly

[0112] 8 Sheet-type press transport assembly at the entrance

[0113] 9. Sheet-shaped pressing and transporting assembly at the exit

[0114] 10 Cutting head

[0115] 11 Cutting head

[0116] 12 Lower side

[0117] 13 Core

[0118] 14 The edge of the short side of the panel

[0119] 15 first lower holding and mounting surface

[0120] 16 Boundary line indicating the starting point of machining

[0121] 17 grooves

[0122] 18 Friction sheet element

[0123] 19 The edge of the short side of the panel

[0124] 20 Top side

[0125] 21 grooves

[0126] 22 grooves

[0127] 23 First spindle

[0128] 24 Second spindle

[0129] 25 Install the tongue

[0130] 26 Mounting grooves

[0131] 27 cutting head

[0132] 28 grooves

[0133] 29 Cutter

[0134] 30 teeth

[0135] 31 sleeve

[0136] 32 spacers

[0137] 33.1÷33.7 cutter

[0138] 34 disc-shaped body of the cutter

[0139] 35 teeth

[0140] 36 Peripheral cutting edge

[0141] 37 lateral cutting edge

[0142] 38 lateral cutting edge

[0143] 39.1÷39.7 cutter

[0144] 40 teeth

[0145] 41 Peripheral cutting edge

[0146] 42 lateral cutting edge

[0147] 43 lateral cutting edge

[0148] 44 Cutter

[0149] 45 teeth

[0150] 46 Peripheral cutting edge

[0151] 47 lateral cutting edge

[0152] 48 lateral cutting edge

[0153] 49 Boundary line indicating the end of machining

[0154] 50 second holding and mounting surface

[0155] 51 Right side wall of groove

[0156] 52 Left side wall of the groove

[0157] 52a Left side wall of the groove

[0158] 53 Bottom of the groove

[0159] 54 side wall of groove

[0160] 55 Bottom of the groove

[0161] 56 Right side wall of the groove

[0162] 57 Bottom of the groove

[0163] 58 Floor

[0164] 59 bonding joint

[0165] 60 Bonded fins

[0166] Movement direction of U floor panels

[0167] α Tilt angle

[0168] Y1 rotation axis

[0169] Y2 rotation axis

[0170] X1 rotation axis

[0171] X2 rotation axis

[0172] X3 rotation axis

[0173] D Cutter diameter

[0174] D1÷D7 gradually changing cutter diameter

[0175] r1 radius of the ellipse

[0176] L1 Length of holding and mounting surface

[0177] L1' Length of holding and mounting surface

[0178] h Groove height

[0179] S1 groove outer width

[0180] S2 Groove Inner Width

[0181] S3 The spacing between the side walls of adjacent grooves

[0182] S4 groove outer width

[0183] S5 groove inner width

[0184] S6 Spacing between the side walls of adjacent grooves

[0185] S7 groove outer width

[0186] S8 groove inner width

[0187] S9 The spacing between the side walls of adjacent grooves

Claims

1. A method for machining parallel grooves (17, 21, 22, 28) in the underside (12) of a floor panel (2) using a device (1) having a rotary machining unit (3, 4) in the form of a cutting head (10, 11, 27), wherein: - inserting the floor panel (2) between the sheet-holding transport assembly (7) and the sheet-pressing transport assembly (8, 9); - the floor panel (2) clamped between the sheet holding and transporting assembly (7) and the sheet pressing and transporting assembly (8, 9) is fed by a linear motion; - causing the cutting head (10, 11, 27) to perform a rotational movement about an axis of rotation (X1, X2, X3; Y1, Y2), and - machining the parallel grooves (17, 21, 22, 28) in the lower side (12) of the floor panel (2) using the feeding movement imparted to the floor panel (2) by the sheet-holding transport assembly (7) and the sheet-pressing transport assembly (8, 9), It is characterized in that The machining of the parallel grooves (17, 21, 22, 28) in the lower side (12) of the floor panel (2) is performed by means of the cutting head (10, 11), the cutting head (10, 11) comprising a set of axially separated profiled disc cutters (33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7) having stepped diameters (D1, D2, D3, D4, D5, D6, D7) ; 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7), wherein the machining of the parallel grooves (17, 21, 22, 28) is carried out with the rotation axis (X1, X2; Y1, Y2) of the spindle (23, 24) of the cutting head (10, 11) inclined at an angle (+α, -α) relative to the plane of the lower side (12) of the machined floor panel (2).

2. The method according to claim 1, characterized in that The floor panel (2) is imparted with a feeding movement by means of a friction sheet element (18) via the sheet holding transport assembly (7) and the sheet pressing transport assembly (8, 9).

3. The method according to claim 1 or 2, characterized in that: Two separate press-conveyor assemblies (8, 9) are used, wherein at least one cutting head (10, 11, 27) is located between the press-conveyor assemblies.

4. The method according to claim 3, characterized in that A stabilizing element in the form of a press shoe (5) is positioned between the separate press-conveying assemblies (8, 9).

5. The method according to claim 1, characterized in that The disc-shaped cutter (33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7; 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7) having an inclined peripheral cutting edge (36, 41) is used to cut the bottom (53, 57) of the groove (21, 22) parallel to the plane of the lower side (12) of the floor panel (2), wherein the inclination angle (+α, -α) of the peripheral cutting edge (36, 41) relative to the rotation axis (X1, X2; Y1, Y2) of the cutting head (10, 11) is equal to the inclination angle (+α, -α) of the rotation axis (X1, X2; Y1, Y2) of the cutting head (10, 11) relative to the plane of the lower side (12) of the machined floor panel (2).

6. The method according to claim 1, characterized in that The disc cutters (33.1, 33.2, 33.3, 33.4, 33.5, 33.6, 33.7; 39.1, 39.2, 39.3, 39.4, 39.5, 39.6, 39.7, 44) used are separated by spacers (32) on the cutting head (10, 11, 27) located on the spindle (23, 24).

7. The method according to any one of claims 1 to 6, characterized in that The milling of the parallel grooves (17, 21, 22, 28) is performed as counter-rotating milling.

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