METHOD FOR THE PRODUCTION OF PANELS FROM A BOARD, PRESS PLATE, METHOD FOR THE PRODUCTION OF A BOARD AND BOARD

Abstract

The present invention is directed to a method for the production of panels from a board. Said panels are produced from the board by dissecting the board along predefined lines. The board comprises a core material board and is laminated with a laminate material layer. At least one impressed region running linear over the complete surface is present in the surface where the laminate material layer is present. The dissecting of the board is accomplished along these impressed regions. After dissecting pairing mechanical locking means at opposite edges of the raw boards are milled out. According to the present invention, the impressed region has a well defined width in order to allow deviations from an ideal dissecting plane, when dissecting the board in order to produce panels. The present invention furthermore relates to a press plate, allowing for the production of boards having well defined impressed regions. Furthermore, the present invention discloses a method for the production of a board, having a specific defined impressed region. In addition, also a board for the production of panels is described.

Claims

1-57. (canceled)

58. A method for the production of panels from a board, the method comprising: providing a board comprising a core material board laminated with a laminate material layer onto a surface of the core material board forming a laminated surface of the board, said board having at least one impressed region, comprising at least one impression of the laminated surface, said at least one impression has a linear progression and extends over the complete surface of the board, wherein in cross-section perpendicular to the extension direction of each of the at least one impression said impressed region having transitions at each outermost region of the impressed region where a transition of the surface to a bottom of the impressed region occurs, said transitions having a width and being adjoined by a part of the impressed region where the bottom of the impressed region is parallel to the surface of the board, linearly dissecting the board along a dissection line running in each of the at least one impressed regions in one or more dissection steps to produce raw boards with a dissection means having a dissection width, milling out pairing mechanical locking means at opposite edges of the raw boards, comprising a first mechanical locking means having a first width and a pairing second mechanical locking means having a second width, wherein the at least one impressed region having an overall width which is the sum of the dissection width, the first width of the first mechanical locking means, the second width of the second mechanical locking means, the width of the transitions, a sacrificial machining width, and a manufacturing tolerance, said manufacturing tolerance being calculated as 0.10 to 3.0-fold of the dissection width.

59. The method according to claim 58, wherein the manufacturing tolerance is calculated as 0.25 to 2.5-fold of the dissection width.

60. The method according to claim 58, wherein the linear dissecting of the board is accomplished by sawing.

61. The method according to claim 58, wherein the at least one impressed region comprises two pairwise and parallel aligned impressions, said impressions having a linear progression and extending over the complete surface of the board.

62. The method according to claim 61, wherein the impressions have a width with a distance between the both impressions fulfilling the following criteria: 0.5 y≤z≤10.0 y, and/or the impressions have a width in between 1.0 and 20 mm, and/or a distance between the both impressions forming each pair of impressions is between 1.5 and 50 mm.

63. The method according to claim 58, wherein the board has rectangular shape with at least one impressed region, or the board comprises at least two impressed regions which are aligned parallel to each other and/or intersect at right angle.

64. The method according to claim 58, wherein the board has a rectangular shape with long sides and short sides, comprising at least one impressed region parallel to the long sides and least one impressed region parallel to the short sides, intersecting each other.

65. The method according to claim 64, wherein the board comprises: 2 to 15 impressed regions parallel to the long sides and/or 1 to 6 impressed regions parallel to the short sides.

66. The method according to claim 58, wherein a depth of the at least one impressed region is between 0.1 and 2.0 mm.

67. The method according to claim 58, wherein the transitions have a linear or curved progression.

68. The method according to claim 58, wherein the width of each of the transitions: in relation to an overall width of the impressed region is between 0.1% to 20%, and/or the width of each of the transitions is between 0.2 and 10.0 mm.

69. The method according to claim 58, wherein the first width of the first mechanical locking means is between 2.0 and 20 mm, and/or the second width of the second mechanical locking means is between 0 and 10 mm.

70. The method according to claim 58, wherein the sacrificial machining width is between 0 and 10 mm.

71. The method according to claim 58, wherein: the cross section of the at least one impressed region or of the impressions is U-shaped, semi-circular, trapezoidal, rectangular, trough-shaped, or a combination thereof, and/or the surface of the board is smooth or comprises impressions, and/or a surface of the transitions, the bottom is smooth, the laminate material layer in the region of the transitions, and/or the bottom (B) are/is unicolor.

72. The method according to claim 58, wherein the pairwise and parallel aligned impressions are separated by a protrusion where the impressions have inner flanks, wherein at least one of the inner flanks is monitored by a detection means, resulting in a monitoring signal which is utilized to control a position of the dissection means during dissecting.

73. The method according to claim 72, wherein the inner flanks are unicolor.

74. A press plate for the production of boards utilized in the production of panels, comprising a main body comprising a pressing surface for pressing a board, said main body comprising: at least one pressing region, having at least one impression means which projects beyond the pressing surface, said at least one impression means has linear progression and extends over the complete pressing surface, wherein in cross-section perpendicular to the extension direction of each of the at least one impression means said pressing region having transitions at each outermost region of the pressing region where a transition of the pressing surface to an upper surface of the pressing region occurs, said transitions having a width and being adjoined by a part of the pressing region where the upper surface of the pressing region is parallel to the pressing surface.

75. The press plate according to claim 74, wherein the at least one pressing region having an overall width which is the sum of the widths of the transitions, a dissection width when the board is dissected with a dissection means having said dissection width, a first width and a second width of pairing mechanical locking means to be milled out at opposite edges of the raw boards, a sacrificial machining width, and a manufacturing tolerance, said manufacturing tolerance being calculated as 0.10 to 3.0-fold of the dissection width.

76. The press plate according to claim 74, wherein the manufacturing tolerance is calculated as 0.25 to 2.5-fold of the dissection width.

77. The press plate according to claim 74, wherein the at least one pressing region comprises two pairwise and parallel aligned impressions means, said impressions means have linear progression and extend over the complete pressing surface of the press plate.

78. The press plate according to claim 77, wherein the impression means have a width (y′) with a distance (z′) between the both impression means fulfilling the criteria: 0.5 y′≤z′≤10.0 y′, and/or the impression means have a width (y′) between 1.0 and 20 mm, and/or a distance (z) between the both impression means forming each pair of impressions is between 1.5 and 50 mm.

79. The press plate according to claim 74, which has rectangular shape with the at least one pressing region extending parallel to the edges of the press plate, or comprises at least two pressing regions which are aligned parallel to each other or intersect at a right angle.

80. The press plate according to claim 74, wherein the press plate has a rectangular shape with long sides and short sides, comprising at least one pressing region parallel to the long sides and least one pressing region parallel to the short sides, intersecting each other.

81. The press plate according to claim 80, wherein the number of pressing regions parallel to the long sides is larger than the number of pressing regions parallel to the short sides.

82. The press plate according to claim 74, wherein a height of the at least one pressing regions is between 0.1 and 2.0 mm, and/or the transitions have linear or curved progression, and/or the width of each of the transitions in relation to an overall width of the pressing region is between 0.1% to 20%, and/or the width of each of the transitions is between 0.2 and 10.0 mm.

83. The press plate according to claim 74, wherein the cross section of the at least one pressing regions is U-shaped, semi-circular, trapezoidal, rectangular, trough-shaped, and/or a combination thereof, and/or the pressing surface is smooth or comprises impressions and/or a surface of the press plate in the region of the transitions and/or an upper surface is smooth.

84. A method for the production of a board for producing panels, the method comprising: providing a core material board, providing a laminate material layer onto a surface of the core material board, joining the laminate material layer and the core material board by pressing with a press plate, wherein the pressing surface of the press plate is pressed onto the laminate material layer, or pressing a core material board laminated with a laminate material layer with a press plate, wherein the pressing surface of the press plate is pressed onto the laminate material layer, wherein the at least one pressing region of the press plate compacts the laminate material layer and/or the core material board, to form at least one impressed region in the laminate material layer and/or the core material board; wherein said press plate is the press plate of claim 74.

85. The method according to claim 84, wherein the at least one impressed region has an overall width which is the sum of the dissection width, the width of the first profile, the width of the second profile, the width of the transitions, a sacrificial machining width (m1+m2), and a manufacturing tolerance (x), said manufacturing tolerance (x) being calculated as 0.10 to 3.0-fold of the dissection width.

86. The method according to claim 84, wherein the surface of the core material board onto which the laminate material layer is provided is smooth or has impressions which correspond to the impression means of the press plate.

87. A board for the production of panels, comprising a core material board laminated with a laminate material layer onto a surface of the core material board forming a laminated surface of the board, said board having at least one impressed region, comprising at least one impression of the laminated surface, said at least one impression has a linear progression and extends over the complete surface of the board, wherein in cross-section perpendicular to the extension direction of each of the at least one impression said impressed region having transitions at each outermost region of the impressed region where a transition of the surface to a bottom of the impressed region occurs, said transitions having a width and being adjoined by a part of the impressed region where the bottom of the impressed region is parallel to the surface of the board.

88. The board according to claim 87, wherein the at least one impressed region having an overall width which is the sum of the dissection width when the board is dissected with a dissection means having said dissection width (d), a first width and a second width of pairing mechanical locking means to be milled out at opposite edges of the raw boards, a sacrificial machining width (m1+m2), as well as a manufacturing tolerance (x) said manufacturing tolerance (x) being calculated as 0.10 to 3.0-fold of the dissection width (d).

89. A panel comprising a core material boars laminated with a laminate material layer onto a surface of the core material board forming a laminated surface of the panel, pairing mechanical locking means at opposite edges of the panels, comprising a first mechanical locking means having a first width at a first edge and a pairing second mechanical locking means having a second width at an opposite edge, wherein along each of the opposite edges an impression of the laminated surface is present, each of the impressions is part of the respective edge, has linear progression and extends over the complete surface of the board, wherein in cross-section perpendicular to the extension direction each impression has a transition at the region farthest from the respective edge where the respective impression is present where a transition of the surface to a bottom of the impression occurs, said transitions having a width and being adjoined by a part of the impressed region where the bottom of the impressed region is parallel to the surface of the board.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0090] FIG. 1 shows a schematic side view of two connected prior art panels and their buildup

[0091] FIG. 2 shows a schematic side view of two connected prior art panels with swelling

[0092] FIG. 3 shows a schematic side view of a V-shaped bevel as known in the art

[0093] FIG. 4 shows a schematic side view of the abutment region of two panels with a V-shaped bevel together with an optimum- and a misaligned abutment line

[0094] FIG. 5 shows a cross-sectional view of a press plate according to the invention as used in the production of a board

[0095] FIG. 6 shows a schematic view of an upturned press plate with pairs of longitudinal- and transversal groove impression means

[0096] FIG. 7 shows a board before being sawed and milled to panels, together with the surface of press plate according to the invention

[0097] FIG. 8 shows a board before being sawed into panels and being milled, together with the surface of a press plate according to the invention

[0098] FIG. 9 shows a schematic side view of the abutment region of two panels produced according to the invention, together with an optimum- and a misaligned abutment line

[0099] FIG. 10 shows schematically how the optimum abutment- and sawing line is detected by optical distance measuring means along an undecorated flank

[0100] FIG. 11 shows two panels dissected from a board with specific measurements

[0101] FIG. 12a shows a schematic side view of two connected panels with a symmetrical U-bevel

[0102] FIG. 12b shows a schematic side view of two connected panels with an asymmetrical U-bevel

[0103] FIG. 12c shows another schematic side view of two connected panels with an asymmetrical U-bevel

DESCRIPTION OF PREFERRED EMBODIMENTS

[0104] In the figures the same reference numerals have the same meaning, even if not explicitly mentioned in the description of the respective drawing.

[0105] FIG. 1 shows a schematic side view of two connected prior art panels 1, 1′ and their buildup, connected along an abutment line 6. Classical medium density or high density (MDF/HDF) laminate flooring panels are known in the art and are commonly made of an (MDF/HDF) core 4, a décor layer 2 commonly consisting of impregnated paper and a (mainly transparent) wear- and abrasion or wear resistant layer 3 plus a backing layer 5 which can be built of a counter draw paper or sound insulation or the like, having a front or visible surface S. They also mostly comprise some variant of locking means L1, L2 such as locking profiles usually on all four long- and short sides of the laminate panels.

[0106] FIG. 2 shows a schematic side view of two connected prior art panels 1, 1′ as described in FIG. 1 with some degree of swelling around a simple butt joint 6. Such swelling at the abutment surfaces of panels may occur if moisture or cleaning fluids enter into an MDF/HDF core 4 or by simple thermal expansion of any material such as MDF or PVC. A similar situation is generated also when two adjacent panels 1, 1′ are not exactly in the same horizontal plane and one adjacent edge is slightly higher than the other, which can be caused e.g. by an uneven underground. A further cause of a similar problem might be slight variations in the panel thickness, caused by incontrollable production parameters. Once such swelling or horizontal misalignment occurs at panel edges, the protective layer 3 can easily be attacked by everyday wear and it can happen that the decorative layer is abraded away, which would result in unaesthetic floor coverings.

[0107] FIG. 3 shows a schematic side view of two connected prior art panels with a V-shaped bevel. Such bevels between adjacent panels are employed both for technical reasons as mentioned above, but also because bevels provide an esthetical overall appearance of the laid flooring panels by contrasting the bevel appearance or color to the décor and because slight unevenness in the underground is less visible and thereby less disturbing. Such V-shaped and decorated bevels are known in the art.

[0108] FIG. 4 shows a schematic side view of the abutment region of two panels 1, 1′ as previously described in FIG. 3 with a V-shaped bevel together with an optimum-aligned abutment line 6 and a misaligned abutment line 6′. It is obvious that even a small misalignment of the saw cut (and thereby also of the subsequently milled profiles)—when producing the panels from sawing them from a (not shown) board—against the pressed bevels (i.e. the V-shaped bevel) is very visible on a V-shaped bevel profile, as any misalignment of the cut would also result in a misalignment of the height of the abutment surface. Such a misalignment of the height of the abutment surface would also result in crevasses or cut-offs which could accumulate liquids and promote swelling.

[0109] FIG. 5 shows a press plate 11 according to the present invention. The press plate comprises a main body 11′ as well as a pressing surface 11″ on which in case of the press plate 11 shown in FIG. 5 a pressing region II is aligned. The pressing region II comprises a pair of impression means 20 which protrude beyond the otherwise smooth pressing surface 11″ of the press plate 11. The impression means 20 run in linear manner over the complete surface of the press plate 11, i.e. in case of FIG. 5 run into the drawing plane. In alternative embodiments the press plate 11 also could comprise more than one pressing regions II running parallel to each other or intersecting each other e.g. at a right angle (see e.g. FIG. 6). It is also possible that the pressing region II comprises only one impression means. The impression means 20 protrude with a height h′ beyond the pressing surface 11″. In the shown cross section the pressing region II has a total width W′. The pressing surface 11″ accordingly exhibits two transitions T1′, T2′ where the pressing surface 11″ is transferred from to the protruding impression means 20, in detail to the upper surface B′ of the impression means 20. Said transitions T1′, T2′ are located at the outermost region of the pressing region (II). As can be seen in FIG. 5 in cross section the transitions T1′, T2′ are convex and have equal widths t1′, t2′. The transitions, however, also could be linear. The upper surface B′ of the pressing region II or the impressing means 20, respectively, runs parallel to the pressing surface 11′. Since the press plate 11 has two distinct impression means 20, these impression means are separated from each other by a gap, in which the upper surface is setback with respect to the upper surface B′. Said gap has a width z, whereas the impression means 20 themselves have a width y′. The total impression width W′ of the impression region accordingly is the sum of the widths y′ of the impression means 20 and the width z of the gap separating the impression means 20. This width W′ on the other hand side is calculated in order to allow the production of boards from which panels can be sawn. Said width W′ is well adjusted in order to avoid that during the sawing of the boards panels are obtained which have mismatched edges.

[0110] FIG. 6 shows a schematic example view of an upturned press plate according to the invention with pairs of longitudinal- and transversal impression means as described in detail in FIG. 5. Both impression means 20 and 21 can be identical as far as their dimensions are concerned, with the exception of their direction.

[0111] FIG. 7 shows a board 10 produced with a press plate 11 as shown in detail in FIGS. 5 and 6 before being sawed into raw panels and being milled to form the final panels. Also shown is the press plate 11 according to the invention. The board principally has the same layered construction as the panels shown in FIG. 1, i.e. has a core 4, laminated with e.g. a decorative layer 2 and a wear layer 3 (the reference numerals of the core, the decorative layer and the wear layer are not shown for reasons of clarity). The core can be laminated with the decorative layer and the wear layer during pressing of the board 10 with the press plate 11. As shown in FIG. 7 an impressed region I comprising two impressions 9 having a width y is formed when pressing the board with the press plate 11. Said impressed region I corresponds to the pressing region II of the press plate 11. The two impressions 9 are separated by a protrusion, corresponding to the gap of the corresponding press plate 11. Said protrusion comprises inner flanks 18. In FIG. 7 also a sawing region 14 and milling regions 13 are displayed where the board in later steps is dissected and where the then to be formed locking elements (already indicated in the board 10 in FIG. 7) will be formed. The locking elements depicted in FIG. 7 are for dimension-illustrating purposes only, since at this stage the laminated board is not yet sawed up and the locking elements are not milled yet either. It is unnecessary to form an impression over the sawing 14 and the profile milling regions 13, as these will be removed anyway. While it is possible to apply a pair of V-shaped impressions by the press plate, U-shaped impressions as shown in FIG. 7 are preferred. After the impressed region I, comprising the impressions 9 is made into the board 10 by the press plate 11, the laminate board 10 is sawed up into panels (not shown). For this purpose, saws with very high sawing speeds (in the range of several meters per second) are employed. Such high sawing speeds obviously enforce a trade-off with precision.

[0112] In analogy to FIG. 7, FIG. 8 shows a board 10 before being sawed into panels and being milled, together with the surface of a corresponding press plate 11 used for its production. In contrast to the embodiment shown in FIG. 7 the impressed region I has only one impression which extends over the complete width of the impressed region. At the same time the corresponding press plate 11 has a pressing region II which exhibits only one pressing means.

[0113] FIG. 9 shows the board 10 of FIG. 8 after the pressing step in a perspective view. Shown is the dissecting step in which the board 10 is dissected with e.g. a buzz saw in two distinct raw panels 1 and 1′. Reference numeral 15 indicates a perfect dissection line. However, if any alignment errors either of the panel 10 or the dissection means, e.g. the buzz saw occur, a dissection e.g. along a mismatching dissection line 16 occurs. The errors can be of systematic origin (e.g. if the buzz saw is slightly mismatched) or of occasional nature (such as e.g. a onetime mismatch of the board 10 during dissection). This mismatching line 16 can e.g. run parallel to the ideal dissection line 15 (e.g. a parallel-shift) and/or slightly angled thereto (as is the case in FIG. 9). Due to the specific determination of the width of the pressing region in the pressing plate 11, or in the corresponding impressed region in the board, the present invention guarantees that the aforementioned errors occurring during the dissection step can be compensated. Since the U-shaped impression shown in FIGS. 8 and 9 has a substantial portion of a near horizontal surface, a slight misalignment of the dissection line does not result in any misalignment of the height of the abutment surface of the produced panels 1, 1′. The misalignment is far less detectable by the human eye and no liquid gathering crevasses are formed. Furthermore, portions of a liquid spill will remain on the substantially near horizontal surface portions of U-shaped bevels and can be cleaned away or evaporate by themselves, while far more liquid would arrive at the abutment surfaces of V-shaped grooves and could possibly cause more swelling there. Accordingly, also the resulting boards 1, 1′ produced by dissection along a mismatched dissection line are shaped to perfectly fit each other so that less rejected boards are produced.

[0114] The decorative layer may also include special portions to decorate the bevel, for example a color contrasting to the panel surface may be used in the bevels. Typically this is a color which is darker than the panel surface decor.

[0115] FIG. 10 displays the dissection step with a board 10 according to FIG. 7 comprising an impressed region I with two impressions 9. Since the inner flanks 18 of each of the protrusion between the both impressions 9 is sawed and milled away at a later stage anyhow, it is possible to print a provisional marker onto at least one of these inner flanks 18 by e.g. means of a uniform color or a decorative layer. This marker can then be used together with optical distance sensors 19 to align the high-speed saws in real time, thus providing more accuracy to the sawing process. The marker can be of a special detectable color or can also consist in the simple absence of a décor portion. FIG. 10 schematically shows how the optimum abutment- and sawing line 15 is detected by optical distance measuring means 19 along an undecorated flank 18.

[0116] FIG. 11 shows two panels 1, 1′ after the raw panels cut from a board have been milled in order to obtain the locking means L1, L2. In FIG. 11 the boards 1, 1′ artificially are aligned in a way they have been present in the (no longer existing) board 10 as shown in FIG. 7 or 8. FIG. 11 illustrates the selection of the width W of the impressed region I in the board 10, or the width W′ of the pressing region II in the press plate 11, respectively.

[0117] The at least one impressed region I has an overall width W which is the sum of the dissection width d, the first width l1 of the first mechanical locking means L1 (measured from an abutment line of the upper edge of an according panel 1), the second width l2 of the second mechanical locking means L2 (measured from an abutment line of the upper edge of an according panel 1′), the width t1, t2 of the transitions T1, T2, an sacrificial machining width m1+m2, as well as a manufacturing tolerance x (being the sum of the displayed fractions x.sub.i and x.sub.ii of the manufacturing tolerance x) said manufacturing tolerance x being calculated as 0.10 to 3.0-fold of the dissection width (d).

[0118] The corresponding press plate accordingly has a pressing region II with an overall width W′ which is the sum of the width t1, t2 of the transitions T1, T2 of the impressed region I of the board 10, a dissection width d when the board 10 is dissected with a dissection means having said dissection width d, a first width l1 and a second width l2 of pairing mechanical locking means L1, L2 to be milled out at opposite edges of the raw boards, an sacrificial machining width m1+m2, as well as a manufacturing tolerance x, said manufacturing tolerance x being calculated as 0.10 to 3.0-fold of the dissection width d.

[0119] The manufacturing tolerance x gives some degree of “play” so that when the board is not ideally cut nevertheless usable boards 1, 1′ can be produced.

[0120] FIGS. 12a-c show schematic side views of two connected panels 1, 1′ produced according to the present invention. In order to obtain such finished panels from the raw panels sawed from the board 10, it is necessary to cut a large laminated board into panels and to mill locking elements L1, L2 (mostly in the form of locking profiles) onto the edges of the cut raw panels. Even if the former dissection line does not fully run through the ideal dissection line, the former described “play”, i.e. the additional manufacturing tolerance x guarantees that the finished panels 1, 1′ always abut at the same height. An example of two panels 1, 1′ ideally cut and milled is shown in FIG. 12a. In FIGS. 12b and 12c (reference numerals not shown) cross-sections through non-ideal cut and milled panels 1, 1′ in installed manner are shown. As becomes visible, even though the cutting—and accordingly the abutment line—is not in the very middle of the produced bevel (e.g. if a complete parallel shift of the abutment line has occured), a perfect alignment of the panels 1, 1′ is possible, avoiding the errors of the prior art e.g. discussed in FIG. 4.

LIST OF REFERENCE SIGNS

[0121] 1, 1′ Panel [0122] 2 Decorative layer [0123] 3 Wear layer [0124] 4 Panel core [0125] 5 Backing layer [0126] 6 Optimal butt joint [0127] 6′ Misaligned butt joint [0128] L1, L2 Locking means or elements [0129] l1 width of locking element L1 [0130] l2 width of locking element L2 [0131] I Impressed region [0132] W overall width of impressed region [0133] B Bottom of impressed region [0134] 9 Impressions [0135] y Width of impressions [0136] z Distance between impressions [0137] h Depth of impressions [0138] T1, T2 Transitions of impression s 9 [0139] t1, t2 width of transitions T1, T2 [0140] 10 Board before being sawed and milled to panels [0141] S Surface of board 10 [0142] 11 Press plate [0143] 11′ Main body of press plate [0144] 11″ Pressing surface of press plate [0145] II Pressing region [0146] W′ overall width of pressing region [0147] B′ Surface of pressing region [0148] 20, 21 Impression means [0149] y′ Width of impression means [0150] z′ Distance between impression means [0151] h′ Height of impression means [0152] T1′, T2′ Transitions of impression means 20, 21 [0153] t1′, t2′ Width of transitions T1′, T2′ [0154] 13, 13′ Profile milling region [0155] 14 Sawing region [0156] d Sawing width [0157] m1, m2 Sacrificial machining width [0158] x Manufacturing tolerance [0159] Optimal sawing line [0160] 16 Misaligned sawing line [0161] 17, 17′: Decorated inner bevel flank [0162] 18 Inner flank of the impressions [0163] 19 Optical distance sensor