JP2010012740A - Manufacturing process of flat square wooden material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing process of a flat square wooden material by which the flat square wooden material constituted of two coreless right square timbers bonded together on the inner side of the timber and having an aesthetic appearance are efficiently manufactured in a reduced manufacturing time. <P>SOLUTION: The manufacturing process of the flat square wooden material comprises the step of getting one or two coreless right square timbers 2A and 2B out of a log 1, the step of drying the sawn coreless right square timbers 2A and 2B, and the bonding step of bonding the inner sides of the dried coreless right square timbers. In sawing the two coreless right square timbers 2A and 2B, a log 1 is sawn at two mutually parallel planes 14 and 15 with the heart 1a of the lgn in between to form the inner sides of the sawn timbers 21 and 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a flat member, and more particularly, to a method for producing a centering flat member excellent in design.

Conventionally, as a lumbering method for large diameter wood, (a) from a single log, lumber of a relatively large cross section (regular or flat) used for beams etc., and lumber from the rest A method and (b) a method of lumbering only a board or a small piece from a single log are known.
However, the square member having a large cross section produced by the method (a) has poor drying properties, and it takes a long time to dry until an appropriate moisture content, and it is caused by the core holding material. In addition, there is a problem that cracks are likely to occur on the surface and inside during drying. Glulam can solve these problems, but it is inferior in aesthetics because the laminated part of lamina is conspicuous.
In addition, the large-section square timber produced by the method (a) has a problem that it is inferior in handleability during drying or the like because of its large weight.

  On the other hand, the method (b) is not originally desirable for the use of large-diameter logs, and the problem is that the cutting allowance increases and the lumber yield (the ratio of the product volume to the raw wood volume used) is low. There is also.

The applicant first divides the cored square timber made from the log into two divided materials by dividing the surface including the core into two divided materials, and after drying both divided materials, at least the divided surfaces in each of the divided materials. A method of manufacturing a column or a square for a base, in which unevenness is applied to the divided surfaces and then the divided surfaces subjected to unevenness are bonded to each other through an adhesive using a pressing device to integrate the two divided materials. Proposed (see Patent Document 1).
JP 2002-086415 A

  However, the method described in Patent Document 1 assumes that a relatively small-diameter log is used, and does not assume that a square bar having a large cross section is manufactured from a log having a large-diameter tree. Further, in the method described in Patent Document 1, since the cored square timber produced from the log is divided by the surface including the core, unevenness such as warping is relatively likely to occur in the divided material at the time of drying. When a log is used, it takes time to remove the unevenness before bonding after drying the divided material.

  Accordingly, an object of the present invention is to efficiently produce a rectangular material having a structure in which the two wood-cutting square members are joined to each other and having excellent design properties, thereby reducing the production time. Another object of the present invention is to provide a method for manufacturing a rectangular material.

  In the present invention, a step of cutting two cored square members from one log, a step of drying each of the two cored square members cut out, and bonding the backs of the cored square members after drying And when cutting the two cored square members, the log is cut in two planes parallel to each other across the tree core to generate the back surface of each of the cored square materials The object is achieved by providing a method for manufacturing a rectangular material characterized by the above.

  According to the method for producing a square member of the present invention, a square member having a structure in which two core-excluded square members are joined to each other and having excellent design properties can be efficiently produced. Can be shortened.

Hereinafter, the present invention will be described based on preferred embodiments thereof.
FIG. 1 is a diagram for explaining each stage in one embodiment of the present invention, and FIG. 2 is a side view showing an example of a flat material obtained by the method shown in FIG.

  In this embodiment, the rectangular material 5 shown in FIG. 2 is manufactured through (1) a lumbering process, (2) a drying process, (3) an unevenness removal process, and (4) a joining process.

(1) Lumbering process Logs of large diameter wood are used as raw materials for producing flat bars. As the large-diameter log, as shown in FIGS. 1 (a) and 1 (b), one that can cut the two core-removing square members 2A, 2B is used. The tree species of the large-diameter tree is not particularly limited, and for example, cedar is preferably used.
In the case of making the core-cutting square material, one log 1 is cut along a plurality of planes parallel to the longitudinal direction of the log 1. Various known devices that can cut the log 1 along its longitudinal direction can be used without particular limitation for cutting the log. For example, a band saw, a circular saw, or the like can be used. Among these, a band saw is preferable. Moreover, a twin circular saw, a twin band saw, a gang saw, etc. can also be used suitably.

  In this embodiment, the large-diameter log 1 shown in FIG. 1 (a) is cut sequentially in this order on the plane indicated by 11 to 16 in the figure, and the two shown in FIG. 1 (b) are obtained. The centering square members 2A and 2B are cut out. One of the two centering square members 2A and 2B shown in FIG. 1 (b) is cut out by cutting the log 1 along the planes 11 to 14 in FIG. 1 (a). On the other hand, the other centering square member 2B is cut out by cutting the log 1 along the planes 12, 13, 15, and 16 in FIG. The planes 11, 14, 15, and 16 are parallel to each other, and the planes 12 and 13 are also parallel to each other. The planes 11, 14, 15, 16 and the planes 12, 13 intersect perpendicularly.

  As is clear from FIGS. 1 (a) and 1 (b), the wood back surfaces 21 and 21 of the core-removing square members 2A and 2B respectively have a log 1 and two parallel planes 14 and 15 sandwiching the tree core 1a. The wood surfaces 22 and 22 of the centering square members 2A and 2B are obtained by cutting the log 1 at two planes 11 and 16 in the vicinity of the outer peripheral portion thereof. The other two side surfaces 23 and 24 of the four side surfaces (surfaces excluding the end face) of each of the centering square members 2A and 2B are obtained by cutting the log 1 along the planes 12 and 13 in FIG. It has occurred.

  The distance from the tree core 1a to the planes 12 and 13 is longer than the distance from the tree core 1a to the planes 14 and 15, and shorter than the distance from the tree core 1a to the planes 11 and 16, and the centering square member 2A, As for the grain pattern of 4 sides of 2B, the wood back surfaces 21 and 21 are grain or square, the wood surfaces 22 and 22 are grain, and the two side faces 23 and 24 are square.

  In the present embodiment, when the log 1 is cut along the longitudinal direction at the planes 11 to 16 including the two planes 14 and 15 to cut out the two centering square members 2A and 2B, the two planes are cut. The core part 3 existing between 14 and 15 is cut out in a plate shape as shown in FIG.

Cutting the log 1 with the two parallel planes 14 and 15 sandwiching the tree core 1a so that the cut surfaces are the tree back surfaces 21 and 21, and cutting out the cored squares 2A and 2B. 3 is cut out into a plate shape, and the cored square members 2A and 2B are cut out, so that the two side surfaces 53 having the larger dimension among the four side surfaces (surfaces excluding the end face) of the flat rectangular member 5 to be manufactured, The wood grain pattern that appears in 54
The line 51 appearing at the boundary between the centering square members 2A and 2B is made inconspicuous, and the flat material 5 having excellent design and high product value is obtained.

  In addition, by cutting and removing the tree core portion 3 along the two planes 14 and 15, the degree of twisting and warping that occurs when the two core-cutting square members 2A and 2B are dried is reduced. The work of unevenness removal, which is performed as necessary before the bonding of the square members 2A and 2B, is reduced, and a straight square member can be efficiently obtained.

  From the viewpoint of obtaining a flat material 5 having excellent design properties and from the viewpoint of reducing the portion between the two planes 14 and 15 to be cut out, the distance L1 between the planes 14 and 15 (see FIG. 1A) is two cores. It is preferably 10 to 60% of the lengths L2 and L2 (see FIG. 1B) of each side of the left square members 2A and 2B, and more preferably 20 to 50%.

  In the case of producing a regular square material having a side of 9 cm or more as the two core removal square materials 2A and 2B, the distance L1 between the two planes 14 and 15 is preferably 1.5 to 5 cm, more preferably 2 to 4 cm. More preferably, it is 2 to 3 cm. The thickness T3 (see FIG. 1 (b)) of the cut tree part 3 when the tree part 3 is cut into a plate shape and a regular material having a side of 9 cm or more is sawn is also preferably 1.5 to 5 cm. More preferably, it is 2-4 cm, More preferably, it is 2-3 cm.

  The distance L1 is the position of the wood back surfaces 21 and 21 generated by the cutting at the two planes 14 and 15 in the two centering square members 2A and 2B in the log 1 before cutting ( (Corresponding position of the cut surface), and the distance between the corresponding positions of the cut surface of the log 1 is defined as the distance L1.

  In addition, by cutting the log 1 along the planes 11 to 16 in FIG. 1 (a), a plurality of parts are generated in addition to the two core-cutting square members 2A and 2B and the tree core part 3. It can be cut into an as-is shape or an arbitrary shape such as a rod shape or a plate shape and used for various applications.

(2) Drying step In the drying step, the two cored square members 2A and 2B obtained as described above are dried in a state of being separated from each other as shown in FIG. 1 (c). . At the time of drying, it is preferable that the two centering square members 2A and 2B are simultaneously dried in the same drying chamber. As a method for drying the core-leaved square materials 2A and 2B, various methods conventionally known as drying methods for wood can be used without particular limitation, and natural drying or artificial drying may be used, or a combination of both may be used. . As a preferable method of artificial drying, a method of placing in a drying apparatus in which temperature and humidity can be controlled and drying is exemplified. As a preferable example of the method of using artificial drying and natural drying together, after natural drying for about 1 to 3 months (for example, 1.5 months in summer and 2.5 months in winter), 40 to 70 is performed. Examples thereof include a method of drying for about 10 to 60 days (more preferably about 5 to 30 days) in a drying apparatus adjusted to about ° C (more preferably 50 to 60 ° C). When natural drying is performed before artificial drying, the moisture content that is different for each individual can be dried to a certain extent evenly to the core, and the energy cost of the drying process can be suppressed while preventing cracks on the surface and inside. it can.
Further, as an artificial drying method, high-temperature drying including a drying step of heating a drying chamber containing wood to 90 degrees or more can be performed. For example, steam is injected into the drying chamber to perform initial vaporization, and the temperature in the drying chamber (dry bulb temperature) is heated to 110 ° C. or higher (for example, 115 to 125 ° C.) at once while the wood interior is softened by the steam. Then, drying may be started, and thereafter, as the drying proceeds, a method of performing drying by lowering the temperature stepwise can be employed.

  It is preferable to perform drying of the two core removal square members 2A and 2B so that the moisture content is 15% or less, respectively. By drying until the moisture content is 15% or less, the adhesiveness between the two core removal square members 2A and 2B can be improved, and further by drying until the moisture content becomes 12% or less, the strength is particularly high. An excellent flat material 5 can be easily obtained. However, excessive drying tends to increase the risk of material deformation and internal cracking. Energy costs also rise. Therefore, the moisture content after drying is preferably 8% or more, and the moisture content after drying is 8 to 15%, particularly 8 to 12% from the viewpoint of achieving both good adhesion and energy cost. Preferably there is.

Here, the moisture content of the centering square members 2A and 2B is measured as follows.
The center part in the longitudinal direction of each cored square member 2A, 2B after drying is cut so that the length in the longitudinal direction is 30 mm to obtain a sample, and the weight W1 of the sample is measured. Next, the sample was prepared according to JIS Z 2201. Test method for wood According to the method for measuring the moisture content, the sample is left in a dryer at 105 ° C., and the weight W2 after the sample reaches a constant weight is measured. And a moisture content is calculated | required by the following formula.
Moisture content (%) = (W1-W2) / W2 × 100

By performing the drying in the state of the squared-off square materials 2A and 2B, it is possible to perform the drying in a short time compared to the case of cutting out the cored flat square material having a large cross section directly from the log 1 and drying, The handling property when performing drying or the like is also easy due to its light weight. Furthermore, the occurrence of cracks on the surface and inside of the material can be suppressed or reduced.
In addition, when the cored flat square bar having a large cross section directly cut out from the log 1 is dried, for example, in cedar wood, the moisture content of the core material including the core is 75 to 150%, and the moisture content is 8%. Since it has the characteristic that it is difficult to reduce to ˜15%, it is difficult to dry the material uniformly, and cracks are likely to occur on the surface and inside during drying.

(3) Unevenness processing In the unevenness removal processing, with respect to the wood back surfaces (sawmill surfaces generated during the division) 21 and 21 that are joined to each other at least in each of the two cored square materials 2A and 2B that have been dried. Apply unevenness processing. That is, the cored square materials 2A and 2B after drying may be warped or distorted, and as such, sufficient strength may not be obtained even if they are bonded together. It is preferable that the wood back surfaces 21 and 21 to be subjected to unevenness processing. Of the four sides of the centering square member 2A, 2B, one or more of the surfaces other than the wood back surface 21, that is, the wood surface 22, the side surface 23, and the side surface 24, or all of them can be subjected to unevenness processing. The unevenness processing for the side surfaces 22 to 24 other than the wood back surface 21 can also be performed as a finishing process after joining after joining the centering square members 2A and 2B.
Here, the unevenness removal process is a process for removing warpage and distortion generated on the side surfaces (surfaces other than the end) of the centering square members 2A and 2B. As a means for performing unevenness processing, for example, various known devices such as unevenness planar and molder can be used.

(4) Adhesion process In the adhesion process, the adhesive 4 is applied to the wood back surfaces 21 and 21 of either one or both of the two core removal square members 2A and 2B. FIG. 1 (d) shows an example in which only the one core removal square member 2 </ b> A is applied to the wood back surface 21.
As an adhesive coating method, for example, there is a method of coating using a coating roller in which the adhesive is continuously supplied to the peripheral surface. Various known coating devices such as a spreader and a die coater can also be used. Various known rollers can be used as the coating roller described above, and the adhesive can be supplied to the peripheral surface through the roller or directly to the peripheral surface from the outside. Even in the present embodiment, the back surfaces 21 and 21 that are bonded to each other are surfaces obtained by cutting the log 1 at the two planes 14 and 15 sandwiching the tree core and then subjected to unevenness processing. good.

As the adhesive, various known adhesives can be used without particular limitation, and examples thereof include urea resin, vinyl acetate resin, and aqueous vinyl urethane resin adhesive. Among these, it is preferable to use an aqueous vinyl urethane resin adhesive. The use of an aqueous vinyl urethane resin adhesive makes it easy to obtain a high-strength flat material, for example, a flat material having sufficient strength to be used as a structural material for a wooden house, and is softer than iron even after curing. Further, it is possible to prevent or reduce the damage of the tool or the like when cutting or tenoning the obtained flat material. Further, the aqueous vinyl urethane resin adhesive is advantageous in that it does not deteriorate the appearance even if it protrudes from the surface of the flat rectangular material, and it does not diffuse chemical substances such as formaldehyde into the atmosphere.
The coating basis weight of the adhesive can be determined as appropriate according to the type of adhesive used.

Adhesion of the two cored square members 2A and 2B is performed by bringing the back and back surfaces 21 and 21 of the two square member 2A and 2B into contact with each other, and pressing the upper and lower surfaces of the stacked corer 2A and 2B with a press device. And do it. The centering square members 2A and 2B may be arranged so that the side surfaces 23 and 24 are horizontal, and pressed and pressed from both sides in the horizontal direction.
As the pressing device, various known devices such as a flat plate press and a roll press can be used without particular limitation, but a flat plate press is preferably used. By using a flat plate press, bonding can be performed while applying a uniform pressure over the entire bonding surface, and the flat material 5 having further improved strength and appearance can be manufactured. Moreover, as a press apparatus, both a cold press and a hot press can be used, and the press apparatus which has a high frequency irradiation function can also be used. In addition, it is preferable to apply | coat an adhesive over the whole wood back surface 21 in one or both of the centering square materials 2A and 2B.

  In this embodiment, the flat square member 5 obtained by integrating the centering square members 2A and 2B is further finished. Here, the finishing process is a process of smoothing at least one of the four side surfaces excluding the wood end surface of the flat member 5, and in particular, the line 51 of the boundary between the core removal square members 2A and 2B is formed on the surface. By finishing the pair of appearing side surfaces 53 and 54, the flat material 5 having further excellent design can be obtained. The finishing process is preferably performed on all of the four side surfaces 52, 52, 53, 54. For the finishing process, an apparatus similar to the apparatus used for the unevenness removal process can be used, and it is particularly preferable to use a molder.

Thus, according to the method for producing a flat material of the present embodiment, a natural rectangular material having a wood grain pattern substantially the same as that of a flat material obtained by cutting out a large-section flat material from a single log. 5 can be manufactured efficiently. The method of this embodiment has a high sawing yield from the log 1 of a large diameter tree as a sawing method.
Further, as shown in FIGS. 1 (e) and 2, the obtained rectangular material 5 is a grid of two side surfaces 53 and 54 having a larger dimension among the four side surfaces (surfaces other than the end surface). In addition, since the grid pattern does not include the grain of the removed tree core portion 3, the straight line 51 appearing at the boundary between the centering square members 3A and 3B is inconspicuous. Therefore, the flat material 5 is excellent in design and has a high value as a product. The two side surfaces 52 and 52 having smaller dimensions among the four side surfaces (surfaces other than the end face) of the flat square member 5 are made of the wood surface 22 of the cored square members 3A and 3B. It has become.

  In addition, according to the method for manufacturing a rectangular material of this embodiment, the drying is performed in the state of the centering square materials 2A and 2B, so that the drying time can be shortened, and the time required for the manufacturing can be reduced. The manufacturing cost can also be reduced.

The rectangular material produced by the present invention can be used for a wide variety of applications, and can be preferably used as a structural material in, for example, a wooden building, particularly a wooden house. Examples of structural materials for wooden buildings include columns, beams, and foundations.
The length and cross-sectional dimension of the rectangular material produced according to the present invention can be determined as appropriate according to the specific application. For example, the cross-sectional dimension can be 80 mm × 160 to 150 mm × 300 mm. More specifically, a 90 mm × 180 mm rectangular material, a 105 mm × 210 mm rectangular material, a 120 mm × 240 mm rectangular material, and the like can be exemplified.
The length of the flat material can be set to 2 to 15 m, for example.
The log has a diameter of 25 cm or more, particularly preferably 30 cm or more.

Further, the centering square members 2A and 2B cut out from the log 1 may have slightly different vertical and horizontal dimensions in cross section (cross section orthogonal to the longitudinal direction). The same applies to the unevenness removal processing. However, the vertical / horizontal dimension ratio is preferably about 0.8 to 1.2, more preferably about 0.9 to 1.1, still more preferably 0.95 to 1.05, and particularly preferably 1.
When the vertical dimension and the horizontal dimension of the cross section are different, the distance L1 is preferably the ratio described above with respect to the length L2 in the direction orthogonal to the planes 14 and 15.

As mentioned above, although this invention was demonstrated based on the preferable one Embodiment, this invention is not restrict | limited to such an embodiment, In the range which does not deviate from the meaning of this invention, it can change suitably.
For example, the pair of cored square members to be joined to each other is preferably obtained from logs of the same individual, but may be obtained from different individuals. For example, two cored square members may be cut out from each of a large number of logs, and these may be arbitrarily combined and joined without distinguishing the individual.

Moreover, in the embodiment mentioned above, it cut | disconnects by four planes 12, 13, 14, and 15 shown to Fig.1 (a), and the tree core part 3 of the log 1 is the same as the core removal regular square materials 2A and 2B Although it cut out as a board of width, it cut | disconnects by the planes 14 and 15 without cut | disconnecting by the planes 12 and 13, and cuts the tree core part 3 of the log 1 in the plate shape which has substantially the same width as the diameter of the log 1. Also good. Further, the tree core portion 3 of the log 1 may be cut out as a rod-like body or a plate-like body divided into a plurality of parts.
Moreover, also when cutting the log 1 by 6 planes of the planes 11-16 like the embodiment mentioned above, the order which cuts 6 planes can be changed suitably. Two or more planes may be cut simultaneously.

  In addition, it is preferable that the two cored squares cut out from the log are joined together with a single solid material having the same length as the flat material 5 to produce the flat material 5. Use one or both of the square members connected in the longitudinal direction with finger joints, etc. to remove defects or extend in the longitudinal direction before drying, after drying, before or after unevenness removal. May be.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by this Example.

[Example 1]
A cedar log having a circular cross section of 360 mm in diameter is cut with a wood cutting shown in FIG. 1 (a), two cored squares each having a cross sectional dimension of 135 mm × 135 mm, and one having a cross sectional dimension of 30 mm × 135 mm A plate-shaped tree core portion was cut out. The positions of the wood back surfaces of each of the two cored squares were written in the cross-sectional view of the log before cutting, and the distance between the wood back surfaces was determined. The distance L1 [FIG. 1 (a)] was 36 mm. It was.
The obtained two cored squares were placed in a drying apparatus capable of controlling temperature and humidity, and each was dried in a state of being separated from each other.

  Next, each of the four side surfaces excluding the lumber surface of the cored square member is subjected to unevenness processing using a molder. Bonding was performed using a vinyl urethane resin adhesive. Finally, final finishing was performed with a molder to obtain a rectangular material (length: 4 m) having a cross-sectional dimension of 120 mm × 240 mm.

  The obtained flat rectangular material was excellent in design because the straight line 51 appearing at the boundary between the cored square material was not conspicuous because it was buried in the side grid pattern. In addition, in terms of strength, it had sufficient strength to be used as a structural material (column material, beam material, etc.) for a wooden house.

Fig.1 (a)-FIG.1 (e) are process drawings which show each step in one embodiment of this invention, Fig.1 (a) shows the cross section of the log of the large diameter tree used as a raw material. It is a figure shown with the straight line which shows (grinding), FIG.1 (b) is a figure which shows the core removal regular timber cut out from the log, and a tree core part, FIG.1 (c) is two in a drying process. FIG. 1 (d) is a cross-sectional view showing the centering square member after coating with an adhesive, and FIG. 1 (e) is a rectangular member to be manufactured. FIG. FIG. 2 is a side view showing a side surface of a flat material obtained by one embodiment of the present invention.

Explanation of symbols

1 Log 2A, 2B Straight core square 21 Wood back 22 Wood surface 3 Tree core 4 Adhesive 5 Flat square 51 Straight line appearing at the border of straight core

Claims (3)

  A step of cutting out two cored squares from one log, a step of drying each of the two cored squares cut out, and a step of bonding the backs of the cored squares after drying When cutting the two cored squares, the log is cut in two planes parallel to each other with the tree core sandwiched between them to produce the back surface of each of the cored squares, A method for producing a flat bar.   The method for manufacturing a rectangular material according to claim 1, wherein the cutting in the two planes is performed so that a tree core portion existing between the two planes is cut out in a plate shape.   The square core material according to claim 1 or 2, wherein each of the two cored square materials is a square material having a side length of 9 cm or more and a distance between the two planes of 1.5 to 5 cm. Production method.

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