JP2602236Y2 - Sasara digit - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slab girder used for fixing a step board or a riser, which is a member constituting a staircase.

[0002]

2. Description of the Related Art A conventional sasara girder is mainly composed of a laminated timber laminated with wood blocks, a laminated plywood in which a plurality of plywoods are laminated, and a veneer laminated material (LVL) in which a plurality of veneers are laminated in parallel. After forming into a plate shape with the fiber direction as the longitudinal direction, a decorative layer was appropriately applied to the surface, and a recess for fixing a tread plate or a riser plate was cut and processed.

[0003]

[Problem to be solved by the present invention] However, in such a configuration, since the sasara girder using the laminated wood as a substrate is made of abundantly beautiful wood for makeup called a precious wood, there is a problem that the price becomes extremely high. there were. In addition, in plywood and LVL, there is also a problem that it is difficult to easily obtain high-quality raw wood due to recent depletion of wood resources, unstable price, and the like, which makes it inconvenient for commercialization. .

In order to solve the above-mentioned problems, there has been proposed a girder made of particleboard or fiberboard (hardboard, MDF) obtained from wood waste material, but the weight is very heavy. However, there is a problem that the thickness is required to be increased more than necessary, since labor is required for the construction and the flexural fracture strength is poor compared with the plywood and the laminated wood.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem. The adhesive is applied to small rod-shaped wood chips to unify the fiber directions, and then the fiber directions of the wood chips are lengthened. A plate is formed by pressing and laminating in the direction, and a thin plate is laminated and bonded on both surfaces thereof, and a fixing recess for fixing a tread plate or a riser plate is cut and formed on one surface.

[0006]

According to the present invention, even in the case of a small rod-shaped wood chip obtained from woody waste material, a conventional plywood or assembly can be obtained by using a substrate in which the fiber directions are unified and laminated so that the fiber direction is the longitudinal direction. A material that is not inferior in strength to the material is configured.

Hereinafter, the present invention will be described based on embodiments.

[0008]

1 is a perspective view of a slab of the present invention, 1 is a substrate, 2 is a thin plate, and 3 is a recess.

As the substrate 1, small rod-shaped wood chips obtained from woody waste materials are used. The size of wood chips is 0.5 ~
2.0mm, length 50-100mm, width 10-20mm
Is used. A substrate 1 is formed by applying a water-resistant adhesive such as a phenolic resin or an isocyanate resin to the wood chips and uniforming the fiber directions and laminating and pressing. This substrate 1 is generally made of LSL (Laminated strand).
d lumber). In this example, L having a thickness of 30 mm, a length of 4050 mm, and a width of 240 mm
SL was used as a substrate.

Although the substrate 1 alone has a relatively good flexural breaking strength, the strength is directional and the surface is rough and unsuitable for applying makeup, so the smoothness is improved and the flexural breaking strength is further improved. The thin plates 2 are attached to both sides of the substrate 1 for the purpose of improving the quality. As the thin plate 2, any plate material having a smooth surface such as a plywood, a fiber board, and a synthetic resin board having a thickness of about 3 to 5 mm is used.

A concave portion 3 for fixing a tread plate or a riser plate is formed on one side thereof.

In order to confirm the bending fracture strength, a comparison test was conducted between a sasara girder, a plywood plate and a particle board as a substrate according to an embodiment of the present invention. The dimensions of the test specimen were 40 mm in width, 30 mm in thickness, and 200 mm in length, and the span length was 150 mm.

[0012]

[Table 1]

As shown in the results in Table 1, the substrate (LSL) used for the slab of the present invention has a lower quality than a conventionally used plywood or the like even though it uses wood waste material. It can be seen that when the fiber direction is used in the longitudinal direction, the flexural strength is excellent.

[0014]

[Effect of the Invention] According to the present invention, a small bar-shaped wood chip obtained from woody waste material constitutes a sasara girder which is not inferior in strength as compared to a conventional slab girder using plywood or particle board as a substrate. it can. Therefore, without using expensive laminated wood, hard-to-obtain plywood or raw wood for LVL, poor strength particle board, fiber board, etc.
Sasara girders can be provided at low cost and with stable quality.

[Brief description of the drawings]

FIG. 1 is a perspective view of a sasara girder of the present invention.

[Explanation of symbols]

 1 Substrate 2 Thin plate 3 Recess

Claims (1)

(57) [Scope of request for utility model registration] An adhesive is applied to small rod-shaped wood chips to unify the fiber directions, and the plate shape obtained by laminating and pressing the wood chips in the longitudinal direction is used as the substrate (1). Characterized in that a thin plate (2) is laminated and adhered, and a fixing recess (3) for fixing a tread plate or a riser plate is cut and formed on one side.