JP2015074175A - Pressing device for composite plywood - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressing device for composite plywood, capable of preventing occurrence of warping of the plywood.SOLUTION: There is provided a pressing device 1 for composite plywood applied to production of a composite plywood 3 used as the bed plate of a woody floor material. The composite plywood 3 is produced by laminating a woody substrate 31 and a woody fiber board 32. The pressing device 1 for composite plywood is provided with a lower die 11 disposed at the side of the woody substrate 31 and an upper die 12 disposed at the side of the woody fiber board 32, and is configured so as to press the woody substrate 31 and the woody fiber board 32 by the lower and upper dies 11 and 12. A die surface 111 of the lower die 11 is convexly curved toward the upper die 12, and a die surface 121 of the upper die 12 is concavely curved to fit to the convexly curved die surface 111.

Description

  The present invention relates to a composite plywood pressing device used when manufacturing a composite plywood used as a base plate for a wooden floor material.

  As a composite plywood used as a base plate for a wooden floor material, a laminate in which a wood fiber board is laminated on the surface of a wood substrate made of softwood plywood is disclosed (Patent Document 1). That is, Patent Document 1 discloses a method of manufacturing a composite plywood by placing a wood fiberboard on the surface of a wood substrate via an adhesive and then heat-pressing the whole. Thereby, in the wooden flooring which formed the decorative layer on the surface of the composite plywood, it has been proposed to prevent the irregularities on the surface of the wooden substrate from appearing on the design surface via the decorative layer. That is, unevenness may appear on the surface of the wooden substrate due to, for example, nodes existing on the plywood of the conifer. Although it is difficult to eliminate the unevenness on the surface itself, when the unevenness appears on the design surface through the decorative layer, the design properties of the composite plywood are degraded. Therefore, it has been proposed to prevent irregularities from appearing on the surface (design surface) of the composite plywood by sticking a wood fiber board to the surface of the wood substrate.

JP-A-5-57841

  However, when the wood substrate and the wood fiber board are pressed and bonded, then the warp such that the wood fiber board side (hereinafter referred to as “upper surface side” as appropriate) becomes concave (hereinafter referred to as “concave warp” as appropriate). May occur). The factors include various factors. For example, when a wood substrate and a wood fiber board are bonded by hot pressing (hot pressing), the moisture content of the wood fiber board is reduced and contracted, thereby producing a composite plywood. Recessed warpage occurs. Alternatively, after obtaining a composite plywood, if a decorative layer is formed by sticking or coating a veneer on the upper surface thereof, a concave warp occurs due to tensile stress from the decorative layer. In addition, concave warpage occurs in the composite plywood due to various factors.

  If such a concave warp occurs, the quality as a wooden flooring will be reduced. That is, even if the concave warpage is slight, if a plurality of wooden floor materials are laid to form a floor surface of a house, for example, the smoothness of the floor surface will be affected. Therefore, in the composite plywood used as the base plate of the wooden floor material, it is an extremely important issue to suppress the occurrence of warpage.

  This invention is made | formed in view of this background, and it aims at providing the press apparatus for composite plywood which can suppress generation | occurrence | production of the curvature of a composite plywood.

One aspect of the present invention is a press device for composite plywood used when producing a composite plywood used as a base plate of a wooden floor material,
The composite plywood is formed by laminating a wood substrate and a wood fiber board,
The composite plywood pressing device includes a lower mold disposed on the wooden substrate side and an upper mold disposed on the wooden fiber board side, and the lower substrate and the upper mold are formed on the wooden substrate and the wooden fiber board. And is configured to press
The mold surface of the lower mold is a convex curved mold surface curved convexly toward the upper mold,
The upper die surface is a concave curved die surface that is concavely curved along the convex curved die surface.

In the composite plywood pressing device, the lower mold has a convex curved mold surface, and the upper mold has a concave curved mold surface. Thus, when the composite plywood is obtained by pressing and adhering the wood substrate and the wood fiber board by the composite plywood pressing device, the top surface side (wood fiber board side) of the composite plywood is convex immediately after pressing. (The warp where the upper surface side is convex is hereinafter referred to as “convex warp” as appropriate).
However, after pressing, as described above, the shrinkage of the wood fiber board and the stress from the decorative layer in the subsequent process act to deform the composite plywood. That is, the composite plywood is deformed in a direction in which the convex warpage state is relaxed. As a result, the occurrence of warpage in the composite plywood can be suppressed.

  As described above, according to the present invention, it is possible to provide a composite plywood pressing device that can suppress the occurrence of warpage of the composite plywood.

1 is a partial cross-sectional perspective view of a composite plywood press device in Example 1. FIG. Sectional explanatory drawing of the state in Example 1 just before a press. Sectional explanatory drawing in the state in Example 1 in the press. 1 is a partial cross-sectional perspective view of a composite plywood immediately after pressing in Example 1. FIG. The partial cross section perspective view of the wooden flooring in Example 1. FIG. Sectional explanatory drawing in the state in Example 2 in the press. Sectional explanatory drawing in the state in Example 3 in the press.

  The wooden substrate may be made of a coniferous board. In this case, the design properties of the composite plywood can be effectively improved. In other words, coniferous boards generally have many nodes and are relatively prone to cracking. When such a coniferous board is used for a wooden substrate, there is a concern that unevenness of the wooden substrate may appear on the design surface. In such a case, by arranging the wood fiber board on the surface of the wood substrate, the unevenness of the wood substrate is effectively absorbed, and when the composite plywood is used as a base plate for the wood floor material, the wood floor material The design property of can be effectively improved.

Moreover, the wooden substrate is not limited to a coniferous tree, but may be composed of other tree species such as a broadleaf tree.
Moreover, the said wooden board | substrate shall consist of a plywood formed by laminating | stacking a single board.
In the present specification, expressions such as “upper surface”, “lower surface”, “upper mold”, and “lower mold” are for convenience, and the positional relationship and direction in the vertical direction are particularly limited. It is not a thing. For example, the upper mold does not necessarily have to be arranged on the upper side in the vertical direction with respect to the lower mold.

  Further, the composite plywood has a rectangular shape having a longitudinal direction and a short direction when viewed from the thickness direction, and the convex curved mold surface and the concave curved mold surface are short sides of the composite plywood. It is preferably curved in the direction. In this case, the warp of the composite plywood in the short direction can be suppressed. When the rectangular composite plywood warps, both warpage in the longitudinal direction and warpage in the short direction are conceivable, but the warpage in the longitudinal direction is relatively easy to correct during subsequent processes and construction. On the other hand, in order to correct the warp in the short direction, a large force is required and correction is difficult. Therefore, the composite plywood press device can effectively produce a high-quality wood flooring by suppressing the occurrence of warpage in the short direction of the composite plywood.

  Further, the convex curved surface and the concave curved surface can be formed into a curved shape in both the longitudinal direction and the short direction of the composite plywood. The convex curved surface and the concave curved surface may be curved only in the longitudinal direction of the composite plywood.

(Example 1)
Examples of the composite plywood pressing device will be described with reference to FIGS.
The press device 1 for composite plywood of this example is used when manufacturing the composite plywood 3 used as a base plate of the wooden flooring 2 as shown in FIG.
The composite plywood 3 is formed by laminating a wood substrate 31 and a wood fiber board 32.

  As shown in FIGS. 1 to 3, the composite plywood pressing device 1 includes a lower mold 11 disposed on the wooden substrate 31 side and an upper mold 12 disposed on the wooden fiber board 32 side. The wood fiber board 32 is configured to be pressed by the lower mold 11 and the upper mold 12.

  The mold surface of the lower mold 11 is a convex curved mold surface 111 that is curved convexly toward the upper mold 12, and the mold surface of the upper mold 12 is along the convex curved mold surface 111. The concave curved surface 121 is curved in a concave shape.

The wooden substrate 31 is made of softwood plywood. Moreover, the wood fiber board 32 can consist of a fiber board prescribed | regulated to JIS A 5905: 2003, for example.
Moreover, the composite plywood 3 has a rectangular shape having a longitudinal direction and a lateral direction when viewed from the thickness direction. The convex curved mold surface 111 and the concave curved mold surface 121 are curved in the short direction of the composite plywood 3.

  In other words, the convex curved mold surface 111 and the concave curved mold surface 121 in the composite plywood pressing device 1 are in one direction (hereinafter referred to as “X direction” as appropriate) perpendicular to the pressing direction (hereinafter referred to as “Z direction” as appropriate). In this example, it is not curved in the direction (Y direction) perpendicular to both the Z direction and the X direction. When the composite plywood 3 is pressed by the composite plywood press device 1, the wood substrate 31 and the wood fiber board 32 are placed on the composite plywood press device 1 so that the short direction of the composite plywood 3 is the X direction. Deploy.

Further, in this example, the convex curved mold surface 111 and the concave curved mold surface 121 have the same curvature. However, the convex curved mold surface 111 and the concave curved mold surface 121 may have slightly different curvatures.
Further, the convex curved mold surface 111 is formed with respect to the length L in the X direction between the segments that are in contact with the lateral edges of the composite plywood 3 and the convex curved mold surface 111. The maximum distance D in the Z direction can be set to 1 to 5%. The concave curved surface 121 can also have a similar shape.

Next, a pressing method using the composite plywood pressing device 1 of this example will be described.
First, as shown in FIG. 2, a wooden substrate 31 and a wooden fiber board 32 are arranged so as to overlap each other between the lower mold 11 and the upper mold 12. The wooden substrate 31 is the lower mold 11 side, and the wooden fiber board 32 is the upper mold 12 side. Further, an adhesive is disposed between the wood substrate 31 and the wood fiber board 32.

Next, as shown in FIG. 3, the lower mold 11 and the upper mold 12 are relatively moved in the direction in which they approach each other, and the wooden substrate 31 and the wooden fiber board 32 are pressed. Here, the pressing can be performed by a hot press or a cold press.
In the case of hot pressing, the wood substrate 31 and the wood fiber board 32 are heated while being heated from at least one of the lower die 11 and the upper die 12 during the pressing. Thereby, the wood substrate 31 and the wood fiber board 32 are thermocompression bonded.
On the other hand, in the case of a cold press, the wood substrate 31 and the wood fiber board 32 are pressed against each other at room temperature without applying any particular heat at the time of pressing, so that both are bonded by an adhesive interposed therebetween. .

  In this pressing step, as described above, the wood substrate 31 and the wood fiber board 32 are pressed and bonded between the convex curved mold surface 111 and the concave curved mold surface 121, so that the obtained composite plywood 3 is obtained. As shown in FIG. 4, it becomes a curved shape along these curved shapes. That is, the composite plywood 3 immediately after pressing has a convex warped shape that is convex toward the wood fiber board 32 side (upper surface side).

  However, after that, the convex warpage is gradually deformed into a nearly flat shape. For example, when the wood substrate 31 and the wood fiber board 32 are bonded to each other by hot pressing, the moisture content of the wood fiber board 32 is reduced and contracted, whereby the convex warpage is gradually relaxed and the flat shape is reduced. Get closer to. Alternatively, after obtaining the composite plywood, as shown in FIG. 5, when a decorative layer 21 is formed by sticking or painting a veneer on the upper surface, tensile stress from the decorative layer 21 acts, The convex warp of the composite plywood 3 is relaxed and approaches a flat shape. As a result, the wooden flooring 2 using the composite plywood 3 can be obtained with a small warpage.

Next, the function and effect of this example will be described.
In the composite plywood pressing device 1, the lower mold 11 has a convex curved mold surface 111, and the upper mold 12 has a concave curved mold surface 121. Thus, when the composite plywood 3 is obtained by pressing and bonding the wood substrate 31 and the wood fiber board 32 by the composite plywood press device 1 to obtain the composite plywood 3, the composite plywood 3 is in a state of convex warping immediately after pressing. Become.

  However, after the pressing, as described above, the shrinkage of the wood fiber board 32 and the stress from the decorative layer 21 in the subsequent process act to deform the composite plywood 3 (wood floor material 2). That is, the composite plywood 3 (wood flooring 2) is deformed in a direction in which the state of convex warpage is eased. As a result, the occurrence of warpage in the composite plywood 3 (wood floor 2) can be suppressed.

  Further, since the convex curved mold surface 111 and the concave curved mold surface 121 are curved in the short direction of the composite plywood 3, the warp of the composite plywood 3 in the short direction can be suppressed. When the rectangular composite plywood 3 warps, both the warp in the longitudinal direction and the warp in the short direction can be considered, but the warp in the longitudinal direction is relatively easy to correct during the subsequent process and construction. . On the other hand, in order to correct the warp in the short direction, a large force is required and correction is difficult. Therefore, the composite plywood press device 1 can effectively suppress the occurrence of warpage in the short direction of the composite plywood 3, whereby the high-quality wood flooring 2 can be obtained effectively.

  As described above, according to this example, it is possible to provide a composite plywood pressing device that can suppress the occurrence of warpage of the composite plywood.

(Example 2)
In this example, as shown in FIG. 6, a plurality of composite plywoods 3 are pressed by one composite plywood press device 1.
That is, first, the wooden substrates 31 and the wooden fiber boards 32 are alternately stacked, and this laminate is placed in a lower mold in a state where an adhesive is interposed only between the upper surface of the wooden boards 31 and the lower surface of the wooden fiber boards 32. 11 and the upper mold 12.

Next, by moving the lower mold 11 and the upper mold 12 relative to each other in a direction approaching each other, the plurality of sets of wood substrates 31 and wood fiber boards 32 are pressed and bonded to each other. In this example, the wood substrate 31 and the wood fiber board 32 are bonded by a cold press. Thereby, the some composite plywood 3 is obtained by one press.
In addition, in FIG. 6, although the wooden board | substrate 31 and the wood fiber board 32 which were arrange | positioned between the lower mold | type 11 and the upper mold | type 12 are five pieces each, this is described for convenience, For example, several tens or more sheets can be stacked and pressed. The same applies to FIG. 7 described later.

  Others are the same as in the first embodiment. Of the reference numerals used in this example or the drawings relating to this example, the same reference numerals as those used in the first embodiment denote the same components as in the first embodiment unless otherwise specified.

In the case of this example, a large number of composite plywoods 3 can be manufactured with high production efficiency.
In addition, the same effects as those of the first embodiment are obtained.

(Example 3)
In this example, as shown in FIG. 7, a plurality of composite plywoods 3 are obtained by a single hot press.
In this example, the composite plywood pressing device 1 has an intermediate die 13 in addition to the lower die 11 and the upper die 12. In this example, the composite plywood pressing device 1 has a plurality of intermediate dies 13. Each intermediate mold 13 has a convex curved mold surface 111 on its upper mold surface and a concave curved mold surface 121 on its lower mold surface. The convex curved mold surface 111 and the concave curved mold surface 121 have the same shape as the convex curved mold surface 111 of the lower mold 11 and the concave curved mold surface 121 of the upper mold 12. In other words, in this example, each intermediate die 13 has a lower portion that functions as an upper die and an upper portion that functions as a lower die.

  When the composite plywood 3 is pressed using the composite plywood pressing device 1 of this example, the intermediate mold 13 and the upper mold are interposed between the lower mold 11 and the intermediate mold 13, between the intermediate molds 13. 12, a wood substrate 31 and a wood fiber board 32 are respectively disposed with an adhesive interposed therebetween.

Next, by moving the lower mold 11 and the upper mold 12 relative to each other in a direction approaching each other, the plurality of sets of wood substrates 31 and wood fiber boards 32 are pressed and bonded to each other. In this example, the wooden substrate 31 and the wooden fiber board 32 are bonded by hot pressing. That is, the lower mold 11, the upper mold 12 and the intermediate mold 13 are heated, and each composite plywood 3 is pressurized while being heated. Thereby, the some composite plywood 3 is obtained by one press.
The number of intermediate molds 13, the wooden substrate 31 and the wooden fiber board 32 arranged between the lower mold 11 and the upper mold 12 is arbitrary, for example, pressing several tens or more composite plywoods 3 at a time. Can do.

  Others are the same as in the first embodiment. Of the reference numerals used in this example or the drawings relating to this example, the same reference numerals as those used in the first embodiment denote the same components as in the first embodiment unless otherwise specified.

Also in this example, a large number of composite plywoods 3 can be manufactured with high production efficiency.
In addition, the same effects as those of the first embodiment are obtained.

  In addition to the embodiments described above, various aspects are conceivable as the structure of the composite plywood pressing device and the method of manufacturing the composite plywood using the same. For example, the convex curved surface and the concave curved surface can be curved in both the longitudinal direction and the short direction of the composite plywood.

DESCRIPTION OF SYMBOLS 1 Press device for composite plywood 11 Lower mold 111 Convex curved mold surface 12 Upper mold 121 Concave curved mold surface 2 Wood flooring 3 Composite plywood 31 Wood substrate 32 Wood fiber board

Claims (2)

It is a press device for composite plywood used when manufacturing a composite plywood used as a base plate of a wooden floor material,
The composite plywood is formed by laminating a wood substrate and a wood fiber board,
The composite plywood pressing device includes a lower mold disposed on the wooden substrate side and an upper mold disposed on the wooden fiber board side, and the lower substrate and the upper mold are formed on the wooden substrate and the wooden fiber board. And is configured to press
The mold surface of the lower mold is a convex curved mold surface curved convexly toward the upper mold,
2. The composite plywood pressing device according to claim 1, wherein the upper mold surface is a concave curved mold surface curved in a concave shape along the convex curved mold surface.   The composite plywood has a rectangular shape having a longitudinal direction and a short direction when viewed from the thickness direction, and the convex curved mold surface and the concave curved mold surface are in the short direction of the composite plywood. The press device for composite plywood according to claim 1, wherein the press device is curved.

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