JP7060352B2 - Wood pallet - Google Patents

Description

The present invention relates to a wood pallet technique, and more particularly to a wood pallet made of a wood molded body formed by adhesively joining wood chips with an adhesive.

Conventionally, as a wood molded body formed by adhesively bonding wood chips with an adhesive, for example, a board material or a floor material as a building material for construction, a cargo handling pallet as a transportation material, or the like is well known. This type of wood molded body is generally adhered to the surface of wood chips by using wood chips such as conifers and hardwoods that are crushed and cut into small pieces, pulverized or micro-crushed as wood raw materials. It is manufactured by hot-press molding a product coated with an agent.

As an example of a conventional wood molded body, for example, Patent Document 1 or Patent Document 2 discloses a configuration of a wood pallet for cargo handling in which a pair of particle boards (a pair of pallet bodies) are assembled via legs. Has been done. Such a wooden pallet for cargo handling usually has a cargo handling surface on one side or both sides, and a fork insertion portion into which a forklift claw can be inserted from two or four directions is formed at a distance between the legs.

However, since the above-mentioned conventional wood molded body is an aggregate of wood chips which are small pieces, for example, when it is configured as a cargo handling pallet, it has higher bending strength and rigidity as compared with a pallet made of wood or plywood. In some cases, the mechanical properties of the pallet are inferior, and there is a problem that the load capacity is small as a material for transportation and the load capacity is limited.

By the way, drifting dust such as drifting trees and bamboo in the dam reservoir also hinders water intake such as power generation and hinders the flow of water, so it is important to quickly withdraw the drifting dust from the reservoir for treatment and disposal. In recent years, these drifting dust have been recycled from the viewpoint of environmental conservation, such as controlling the cost of waste treatment and reducing CO ₂ emissions associated with incineration, which is one of the important tasks. A measure to reuse the waste without treating it is being considered.

In particular, among the drifting dust, driftwood has been crushed and recycled into wood chips and compost, and it has become possible to utilize this as wood chips in wood molded bodies. On the other hand, for driftwood, effective measures for recycling have not yet been established, and in terms of the use of drifting dust, if driftwood and driftwood can be recycled together and used, the above will be mentioned. It is possible to reduce the processing cost and to further promote environmental conservation by effectively utilizing unused materials.

For example, as disclosed in Patent Document 3, focusing on the strength of bamboo material, a transport pallet using bamboo material as a structural member (aggregate material) has been proposed, but such a configuration has a plurality of configurations. Since the bamboo material was formed by arranging it in a predetermined position and covering it with a resin sheet or the like, the mechanical properties of the wood molded body made of the wood chips described above were improved, and the unused material such as drifting dust was used. It is not possible to solve technical issues such as effective utilization and social demands.

Japanese Unexamined Patent Publication No. 08-183531 Japanese Unexamined Patent Publication No. 2014-172645 Japanese Unexamined Patent Publication No. 2009-132452

Therefore, the present invention solves the above-mentioned conventional problems regarding wood pallets , and an object of the present invention is to provide a wood pallet made of a wood molded body that contributes to environmental conservation by effectively utilizing unused materials while improving mechanical properties. And.

The problem to be solved by the present invention is as described above, and next, the means for solving this problem will be described.

That is, in claim 1, in a wood pallet made of a wood molded body formed by adhering and joining wood chips with an adhesive, a rectangular base material portion in a plan view is provided, and the inside of the base material portion is reinforced. As a material, a plurality of bamboo materials obtained by vertically dividing bamboo in the fiber direction and cutting it to a predetermined length are integrally embedded by being adhesively bonded to a wood chip at the time of molding, and the plurality of bamboo materials are placed around the periphery of the base material portion. It is arranged along the same plane at a central position in the thickness direction of the base material portion so as to be along an oblique direction with respect to the periphery at a location other than the peripheral edge of the base material portion .

In claim 2, the bamboo material is arranged along a rib portion that bulges linearly on one plane side of the base material portion.

In claim 3 , the plurality of bamboo materials are arranged so as to intersect each other in a mesh pattern.

In claim 4 , a plurality of legs are arranged on one plane of the base material, and a pair of base materials are assembled via the legs.

In claim 5 , the plurality of bamboo materials are arranged so as to be separated from each other by the legs.

As an effect of the present invention, it is possible to contribute to environmental conservation by effectively utilizing unused materials while enhancing mechanical properties.

It is a perspective view which showed the overall structure of the wood pallet which concerns on one Example of this invention. It is a front view of a wooden pallet. It is a bottom view of a pallet body. It is a partially enlarged view of the pallet body of FIG. It is sectional drawing which shows the arrangement composition of the bamboo material seen from the direction orthogonal to a rib part. FIG. 5 is a cross-sectional view taken along the line AA of FIG. It is a figure which showed the sampling place of the sample piece for measuring the mechanical property. It is a graph which showed the bending strength of a leg interstitial material and a fork interstitial material.

Next, a mode for carrying out the invention will be described.

In the following embodiment, as an example, a case where a wood pallet 1 as a material for transportation is configured will be described. However, as will be described later, the examples of the wood molded body are not limited to the wood pallet 1.

As shown in FIGS. 1 and 2, the wood pallet 1 of the present embodiment is configured as a double-sided pallet in which a pair of pallet bodies 2 and 2 are assembled and has cargo handling surfaces on both sides, specifically, a pair. The base material portions 20 and 20 of the pallet bodies 2 and 2 are integrally assembled via a plurality of leg portions 21 and 21 .... A fork insertion portion 10 into which a fork lift claw (fork) can be inserted is formed at a distance between the pair of pallet bodies 2 and 2 and adjacent legs 21 and 21, and the fork insertion portion 10 is formed. The wooden pallet 1 is opened in four directions, and forklift claws can be inserted from the four directions.

As shown in FIGS. 2 and 3, the pallet body 2 forms the upper half body or the lower half body of the wood pallet 1, and the base material portion 20 is formed into a rectangular shape (square shape in this embodiment) in a plan view. And a plurality of (nine in this embodiment) leg portions 21.21 ... Protruding on the facing surface 20b on one plane side of the base material portion 20, and also swelling linearly on the facing surface 20b. A plurality of rib portions 22, 22 ... Etc. are provided, and the bamboo material 23 as a reinforcing material is integrated with the wood chips (aggregate) inside the pallet body 2 (base material portion 20). (See FIGS. 5 and 6 etc.).

The wood chips that are the main material of the pallet body 2 are not particularly limited to wood raw materials, but for example, coniferous trees such as pine, sugi, and cypress, or hardwoods such as lauan, kapole, and poplar are used. Wood raw materials are crushed and cut into small pieces or tiny pieces. Further, as these wood raw materials, in addition to driftwood drifting in the dam reservoir, construction waste materials and thinned wood (including thinned wood such as leaves, end trees, branches, and roots) can be used.

Further, as the adhesive used at the time of molding the pallet body 2, an adhesive used for a known wood molded body (particle board or the like) can be adopted, for example, a urea resin adhesive, a melamine resin adhesive, a urea / melamine resin. A heat-curable resin such as an adhesive, a phenol resin adhesive, a resorcinol resin adhesive, a urethane resin adhesive, a furfural resin adhesive, and an isocyanate resin adhesive is used alone or in combination of two or more. Above all, a urea resin adhesive or a urethane resin adhesive is preferably used from the viewpoint of mechanical properties and processability.

The amount of the adhesive added (applied amount) at the time of molding is not particularly limited, but the dried wood chips and the bamboo material 23 are combined from the viewpoint of mechanical properties such as tensile strength and bending strength and workability. It is adjusted to be 5 to 25 parts by weight, preferably 10 to 15 parts by weight with respect to 100 parts by weight.

The pallet body 2 is configured as a wood molded body formed by adhesively joining wood chips with an adhesive, and the base material portion 20, the leg portion 21, and the rib portion 22 are integrally molded. As a molding method of the pallet body 2, a known method can be adopted, but as an example, a wood chip coated with an arbitrary adhesive is put into a cavity of a mold having a predetermined shape, and 120 It is formed by pressure pressing at 500t to 700t under heating conditions of ° C. to 150 ° C. The bamboo material 23 as a reinforcing material is placed at a predetermined position of the wood chips accumulated in the cavity of the mold, and is molded in a state of being covered with the wood chips so that the surface of the bamboo material 23 is not exposed. It is adhesively joined together with the wood chip.

As shown in FIGS. 3 to 6, the base material portion 20 has a horizontal cargo handling surface 20a on which a load is placed on the upper surface thereof, and faces the base material portion 20 of the other pallet body 2 on the lower surface surface. A horizontal facing surface 20b is formed, and the leg portion 21 and the rib portion 22 described above are projected from the facing surface 20b, respectively, and the bamboo material 23 is embedded inside the base material portion 20 as described above. ..

The leg portion 21 is projected from the facing surface 20b in a quadrangular pyramid shape, and a convex portion 21a as a columnar protrusion and a concave portion 21b as a bottomed columnar hole are provided on the horizontal abutment surface of the top portion. There is. In the leg portion 21, the pair of convex portions 21a / 21a and the pair of concave portions 21b / 21b are arranged at positions symmetrical with respect to the central axis orthogonal to the abutting surface and at each apex position of the square centered on the central axis. ing. Further, a plurality of legs 21 having the same shape are arranged on the peripheral edge and the central portion of the base material portion 20 at equal intervals, and specifically, the corner positions (4) of the base material portion 20. (Places), the center position (4 places) and the center position (1 place) around the periphery, for a total of 9 places.

In the state where the pair of pallet bodies 2 and 2 are assembled, the convex portion 21a of one leg portion 21 is fitted into the concave portion 21b of the other leg portion 21 and joined to each other in the corresponding leg portions 21 and 21. The contact points of the legs 21 and 21 are maintained in a joined state by the frictional force of the fitted convex portions 21a and concave portions 21b, or are joined and integrated by a joining means such as a known adhesive. (See FIG. 1 or FIG. 2).

The rib portions 22 are arranged at a distance between the adjacent leg portions 21 and 21, and are projecting from a plurality of locations on the facing surface 20b so as to have the same thickness direction dimension. Specifically, the rib portion 22 of the present embodiment is linearly extended so as to connect the leg portions 21 arranged at the corner positions of the base material portion 20 along the peripheral edge of the base material portion 20. The peripheral rib 22a, the central rib 22b extending linearly so as to connect the leg portion 21 arranged at the central position around the base material portion 20, and the diagonal direction with respect to the periphery of the base material portion 20. A diagonal rib 22c extending linearly from the leg portion 21 arranged at the corner position of the base material portion 20 toward the leg portion 21 arranged at the center position is provided (FIG. 3). reference). The peripheral ribs 22a, the central ribs 22b, and the diagonal ribs 22c are formed so as to intersect or connect with any of them in a mesh pattern, and a part of the diagonal ribs 22c is continuous with the peripheral ribs 22a or the central ribs 22b and the diagonal ribs 22c. It is formed so that some of them intersect with each other.

The bamboo material 23 is formed as a divided bamboo material, and the bamboo is vertically (long-axis direction) divided in the circumferential direction using a known dividing machine or the like, cut to a predetermined length, and has a length of a rectangular cross section having a predetermined size. The one divided into plates is used. The wood pallet 1 of this embodiment has various sizes. For example, when the bamboo material 23 is molded so as to have a circumference of 1100 mm × 1100 mm, the bamboo material 23 has a width of 5.0 mm to 15 mm and a thickness of 5.0 mm to 15 mm. It is preferably divided into long plates having a rectangular cross section so as to have a length of 0.2 mm to 10 mm and a length of 300 mm to 1000 mm.

The type of bamboo, which is the raw material of bamboo material 23, is not particularly limited, but from the viewpoint of its high strength and low cost, Moso bamboo and Matake are typically used, and the flow drifts into the dam reservoir. Bamboo and thinned wood can be used. Further, as the bamboo, one having the branches and leaves removed is preferably used, and one having an epidermis portion may be used as it is, or one having the epidermis portion peeled off may be used.

Regarding the arrangement configuration of the bamboo material 23, regarding the arrangement in the plane direction of the base material portion 20, the plane surface of the base material portion 20 is completely embedded inside without being exposed on the surfaces of the base material portion 20 and the rib portion 22. One or more bamboo materials 23 are arranged along the predetermined rib portions 22 (peripheral ribs 22a and diagonal ribs 22c) so as to be located on substantially the same plane along the direction (direction of the cargo handling surface 20a). , A part or all of the whole is configured to have a mesh-like shape (lattice-like or twill-like) in a plan view (see FIGS. 3 to 5 and the like).

Specifically, by disposing one or more bamboo materials 23 along the peripheral ribs 22a provided on the peripheral edge of the base material portion 20, the bamboo material 23 is flat as a whole at the peripheral edge portion of the base material portion 20. It is arranged in a viewing rectangle. Further, among the diagonal ribs 22c provided diagonally with respect to the periphery of the base material portion 20, three diagonal ribs 22c provided at parallel distances and one rib provided intersecting the diagonal ribs 22c. By arranging one or a plurality of bamboo materials 23 on the 22c, the bamboo materials 23 are arranged in a twill pattern in which the bamboo materials 23 partially intersect at a position other than the peripheral edge of the base material portion 20.

On the other hand, regarding the arrangement of the base material portion 20 in the thickness direction, it is preferably configured to be arranged in the vicinity of the center position in the thickness direction of the base material portion 20 (see FIGS. 5 and 6). In this embodiment, the "center position of the base material portion 20 in the thickness direction" is not the thickness direction dimension T1 between the cargo handling surface 20a and the facing surface 20b, which is the vertical plane of the base material portion 20, but the cargo handling surface 20a. It refers to the dimension T2 in the thickness direction between the rib portion 22 and the tip of the rib portion 22. By disposing the bamboo material 23 in the vicinity of the center position in the thickness direction of the base material portion 20 in this way, it is possible to effectively prevent warping and distortion that occur in the base material portion 20.

Next, a bending test of the pallet body 2 was performed in the following manner to evaluate the mechanical properties of the wood molded body of this example.

The pallet body 2 used for the test constitutes a wood pallet 1 having a circumference of 1100 mm × 1100 mm. An adhesive (urea resin adhesive or urethane resin adhesive) was added by spraying so as to be a part by weight to prepare a wood chip having the adhesive coated on the surface. Next, this is put into the cavity of the mold having the shape of the pallet body 2 and accumulated, and the width is 5.0 mm to 15 mm, the thickness is 0.2 mm to 10 mm, and the length is on the surface of the integrated wood chips. One or more bamboo materials having a thickness of 300 mm to 1000 mm were arranged at predetermined positions (positions along the peripheral ribs 22a and the predetermined diagonal ribs 22c of the base material portion 20). Then, the pallet body 2 was obtained by pressure-pressing at 600t to 650t under heating conditions of 130 ° C. to 140 ° C. with the surface of the bamboo material covered with wood chips so as not to be exposed (Examples 1 to 1). 4). Further, by the same method, a pallet body 2 having no bamboo material was also obtained. (Comparative Examples 1 and 2).

The sample piece is formed by dividing the above-mentioned pallet body 2 into a predetermined shape, and specifically, as shown in FIG. 7, between adjacent girders where strength is required when loading on the cargo handling surface. Sample pieces A1 to A4 (Example 1, Example 2, Comparative Example 1) of the leg interstitial material, which is the part of the above, and the base material part where strength is required when the claw is inserted into the fork insertion part and lifted by the forklift. Sample pieces B1 to B3 (Example 3, Example 4, Comparative Example 2) of the fork interstitial material which is the peripheral portion and the central portion of the above were used.

In the bending test, the bending strength (N) was measured by a three-point bending test of the sample piece using a universal testing machine (manufactured by Shimadzu Corporation: AGS-20kND). As the measured values of the bending strength, the average value of the measured values of the sample pieces A1 to A4 was adopted for the leg interleaving material, and the average value of the measured values of the sample pieces B1 to B3 was adopted for the fork interleaving material.

From the test results shown in Table 1, Table 2 and FIG. 8, the pallet body 2 of this example has a leg interstitial material as compared with the conventional pallet body 2 having no bamboo material (Comparative Example 1 and Comparative Example 2). In the case (Examples 1 and 2), the bending strength (N) is improved by a maximum of 185%, and in the case of a fork interleaving material (Examples 3 and 4), the bending strength (N) is improved by a maximum of 161%. Is allowed to do. From this, it was confirmed that in the wood molded body of this example, the mechanical properties are enhanced by embedding the bamboo material in the base material portion.

As described above, the wood pallet 1 of the present embodiment is a wood molded body formed by adhering and joining wood chips with an adhesive, and is provided with a base material portion 20 having a rectangular shape in a plan view, and the inside of the base material portion 20 is provided. In addition, as a reinforcing material, the bamboo material 23, which is obtained by vertically dividing bamboo in the fiber direction and cutting it to a predetermined length, is integrally embedded along the plane direction of the base material portion 20, so that the mechanical properties are improved as compared with the conventional wood pallet. At the same time, it is possible to contribute to environmental conservation by effectively utilizing unused materials.

That is, in the wood pallet 1 of the present embodiment, since the base material portion 20 is formed by burying the bamboo material 23 as a reinforcing material along the plane direction, the base material portion 20 formed as an aggregate of wood chips Bending strength, rigidity, and the like can be improved, and the load bearing capacity is improved, so that the limit of the load capacity as a transportation material can be expanded, and it becomes possible to use it in a wider range of applications. In addition, since bamboo material 23 is used together with wood chips, driftwood and bamboo, which are drifting dust in the dam reservoir, can be recycled and utilized at the same time, and such unused materials can be effectively utilized for further environmental conservation efforts. It can be expected to proceed.

In particular, in the wood pallet 1 of the present embodiment, since the bamboo material 23 is arranged along the rib portion 22 that linearly bulges on one flat side of the base material portion 20, the rib portion 22 further bases the material. The bending strength and rigidity of the portion 20 can be improved, and the thickness direction dimension of the base material portion 20 can be reduced by embedding the bamboo material 23 in the rib portion 22, and the weight and cost of the wood pallet 1 can be reduced. Can be done.

Further, in the wood pallet 1 of the present embodiment, the bamboo material 23 is arranged along the peripheral edge of the base material portion 20, and is arranged diagonally with respect to the periphery of the base material portion 20, and the bamboo material 23 is arranged in a mesh shape. Since it is arranged so as to intersect with each other, it effectively enhances the mechanical characteristics of the place where stress (load) is applied, especially when loading on the cargo handling surface or lifting with a forklift, and facilitates the rigidity required for practical use. Can be secured.

As described above, the wood molded body and the wood pallet of the present invention are not limited to the above-mentioned examples, and various modifications can be made as long as the object of the present invention is not deviated.

That is, in the woody pallet 1 of the above-described embodiment, the configuration formed by the pair of pallet bodies 2 and 2 has been described. It may be assembled to the frame body, or it may be formed from only one pallet body 2, the leg portion 21 is arranged on one flat side of the base material portion 20, and the forklift claws are separated from the leg portion 21. It may be configured so that the insertable fork insertion portion 10 is formed.

Further, in the wood pallet 1 of the above-described embodiment, the leg portion 21 is provided with a pair of convex portions 21a / 21a and a pair of concave portions 21b / 21b at symmetrical positions with respect to the central axis orthogonal to the butt plane. As described above, the arrangement configuration of the convex portion 21a and the concave portion 21b is not limited to this, and at least one convex portion 21a and the concave portion 21b may be provided on one leg portion 21, respectively.

Further, in the wood pallet 1 of the above-described embodiment, a configuration in which a plurality (9 pieces) of the same shape are provided in each of the leg portions 21 has been described, but the arrangement configuration of the leg portions 21 is not limited to this. For example, the legs 21 may be formed so as to have different shapes depending on the arrangement.

Further, in the wood pallet 1 of the above-described embodiment, the bamboo material 23 is arranged along the peripheral edge of the base material portion 20 and is arranged diagonally with respect to the periphery of the base material portion 20 so as to intersect in a mesh pattern. However, the arrangement configuration of the bamboo material 23 is not limited to this, and a part or all of the bamboo material 23 can be arranged in a grid pattern, a twill pattern, or the like in a plan view to be arbitrarily configured. .. The rib portion 22 is preferably arranged so that the bamboo material 23 can be arranged according to the arrangement configuration of the bamboo material 23.

Further, in the wood pallet 1 of the above-described embodiment, the vertical orientation of the bamboo material 23 in the state of being embedded in the base material portion 20 is not particularly limited, and as illustrated in FIGS. 5 and 6, in a cross-sectional view. Not only the side surface in the lateral direction may be arranged so as to face in the vertical direction, but the side surface in the lateral direction may be arranged so as to face in the vertical direction. When the bamboo material 23 is arranged so that the side surface in the lateral direction faces up and down as in the latter case, the bulkiness in the thickness direction at the intersection of the bamboo material 23 is reduced, and the thickness of the base material portion 20 is reduced. The directional dimension (T1 or T2) can be made small.

Further, in the wood pallet 1 of the above-described embodiment, the configuration in which one or more bamboo materials 23 are arranged along the predetermined rib portion 22 has been described, but for example, one for the peripheral rib 22a and one for the diagonal rib 22c, respectively. One bamboo material 23 may be arranged, and a plurality of bamboo materials 23 having different lengths may be arranged on the diagonal rib 22c according to the rib shape.

Further, the wood molded body is not only configured as a wood pallet as a transportation material as in the above-described embodiment, but also, for example, a wood board material as a building material for construction or a floor having a certain height. It may be configured as a wooden floor material such as a floor material for taking a space and making a double floor.

1 Wood pallet 2 Pallet body 10 Fork insertion part 20 Base material part 20a Cargo handling surface 20b Opposing surface 21 Leg part 21a Convex part 21b Recessed part 22 Rib part 22a Peripheral rib 22b Central rib 22c Diagonal rib 23 Bamboo material

Claims (5)

In a wood pallet made of a wood molded body formed by bonding wood chips with an adhesive.
A rectangular base material in a plan view is provided,
A plurality of bamboo materials obtained by vertically dividing bamboo as a reinforcing material in the fiber direction and cutting it to a predetermined length are integrally embedded inside the base material portion by being adhesively bonded to wood chips during molding .
The plurality of bamboo materials are located at the center position in the thickness direction of the base material portion so that the plurality of bamboo materials are along the periphery at the peripheral edge of the base material portion and along the diagonal direction with respect to the periphery at locations other than the peripheral edge of the base material portion. Arranged on the same plane,
A wooden pallet characterized by that. The woody pallet according to claim 1, wherein the plurality of bamboo materials are arranged along a rib portion that bulges linearly on one plane side of the base material portion. The woody pallet according to claim 1 or 2, wherein the plurality of bamboo materials are arranged so as to cross each other in a mesh pattern. The woody pallet according to any one of claims 1 to 3, wherein a plurality of legs are arranged on one plane of the base material and a pair of base materials are assembled via the legs. The woody pallet according to claim 4, wherein the plurality of bamboo materials are arranged at intervals of the legs.

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