WOODEN CONTAINER AND A PROCESS FOR MANUFACTURING THEREOF

Abstract

A wooden container formed by a wooden sheet is provided. The wooden container (1) is formed by a ply wood sheet comprising two wooden sheets chosen from a large number of wooden sheets, one being an inferior sheet (6a) including at least one spoiled portion and another one being a superior sheet (6b) including no such spoiled portion. The inferior and superior sheets are laid with each other and glued mutually. The container comprising a bottom wall (2) and a peripheral wall (3) is formed inside with the superior sheet (6b) and outside with the inferior sheet (6a). Adhesion film (9) is formed between contacted surfaces of the sheets by lignin oozed from wood content. Supplementary adhesion may be added if necessary.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1(A) to FIG. 1(C) show an embodiment of wooden container according to the present invention; FIG. 1(A) is a perspective view of the container, FIG. 1(B) is a longitudinal sectional view thereof, and FIG. 1(C) is an enlarged sectional view showing a broken part of plywood sheet.

FIG. 2(A) to FIG. 2(D) show a process of producing wooden sheets for manufacturing wooden containers according to the present invention: FIG. 2(A) is an explanatory view showing a slicing step of superior sheets, FIG. 2(B) is an explanatory view showing a slicing step of inferior sheets, FIG. 2(C) is an explanatory view showing an expansion step of the sheets, and FIG. 2(D) is an explanatory view showing a drying step of the sheets.

FIG. 3 is a sectional view showing an embodiment of press apparatus according to the present invention.

FIG. 4 is a sectional view showing the press apparatus wherein a first forming step to form an intermediate product is carried out.

FIG. 5 is a sectional view showing the press apparatus wherein a second forming step to form a finished product is carried out.

FIG. 6(A) and Fig. (B) are enlarged sectional views of the press apparatus in which an adjusting plate is used; FIG. 6(A) shows a forming step wherein a thin adjusting plate is used, and FIG. 6(B) shows a forming step wherein a thick adjusting plate is used.

Claims

1. A wooden container comprising a plywood sheet (6) which comprises an inferior wooden sheet (6a) having at least one spoiled portion (7) and a superior wooden sheet (6b) having no such spoiled portion, said container being formed with a bottom wall (2) and a peripheral wall (3) by pressing said plywood sheet (6) within up-and-down dies of a press apparatus, wherein an inside of the container is formed by said superior wooden sheet (6b) and an outside of the container is formed by said inferior wooden sheet (6a).

2. A process for manufacturing a wooden container including a bottom wall (2) and a peripheral wall (3) comprising: a step of providing a large number of wooden sheets by slicing wooden pieces and forming a smooth surface and a fluffy rough surface (8) on respective sides of each wooden sheet;a step of selecting a pair of wooden sheets, one being an inferior sheet (6a) including at least one spoiled portion (7) and another one being a superior sheet (6b) including no such spoiled portion, and forming a plywood sheet (6) by laying said two sheets (6a, 6b) together by contacting the respective fluffy rough surfaces (8); anda step of carrying out heating pressurization to said plywood sheet (6) between male and female dies of a press apparatus under the state that said superior sheet (6b) faces the male die and said inferior sheet (6a) faces the female die whereby said wooden container having said bottom wall (2) and said peripheral wall (3) is formed while gluing said two sheets (6a, 6b) by oozing lignin and moisture from wood content to said rough surfaces (8).

3. A process for manufacturing a wooden container including a bottom wall (2) and a peripheral wall (3) having a surrounding edge (4) extending along an upper edge thereof in a shape of circular extending downward in cross section comprising: a step of providing a large number of wooden sheets by slicing wooden pieces and forming a smooth surface and a fluffy rough surface (8) on respective sides of each wooden sheet;a step of selecting a pair of wooden sheets, one being an inferior sheet (6a) including at least one spoiled portion (7) and another one being a superior sheet (6b) including no such spoiled portion, and forming a plywood sheet (6) by laying said two sheets (6a, 6b) together by contacting the respective fluffy rough surfaces (8);a first forming step of producing an intermediate product (1a) by carrying out heating pressurization to said plywood sheet (6) on its center region except its peripheral region between male and female dies of a press apparatus under the state that said superior sheet (6b) faces the male die and said inferior sheet (6a) faces the female die whereby said plywood sheet (6) is formed with a bottom wall (2a) and a peripheral wall (3a) having an edge portion (4a) extending upwardly therefrom while gluing said two sheets (6a, 6b) by oozing lignin and moisture from wood content to said rough surfaces (8); anda second forming step of forming a finished product (1) by carrying out further heating pressurization to said intermediate product (1a) by clamping entire part thereof whereby said bottom and peripheral walls (2a, 3a) are firmly pressed, said edge portion (4a) is formed with said surrounding edge (4), thereby the wooden container as the finished product formed with said bottom wall (2), said peripheral wall (3) and said surrounding edge (4) is produced.

4. A process for manufacturing a wooden container according to claim 2 wherein said inferior and superior sheets (6a, 6b) are dried to reduce moisture in wood content in advance of forming the plywood sheet (6), and said reduced moisture of limited quantity is oozed together with lignin form wood content to contacting surfaces of the inferior and superior sheets (6a, 6b) when heating pressurization is carried out to the plywood sheet (6), thereby said contacting surfaces are glued mutually.

5. A process for manufacturing a wooden container according to claim 3 wherein said inferior and superior sheets (6a, 6b) are dried to reduce moisture in wood content in advance of forming the plywood sheet (6), and said reduced moisture of limited quantity is oozed together with lignin form wood content to contacting surfaces of the inferior and superior sheets (6a, 6b) when heating pressurization is carried out to the plywood sheet (6), thereby said contacting surfaces are glued mutually.

6. A process for manufacturing a wooden container according to claim 2, wherein powder of starch is applied on at least one of the rough surfaces (8) of the inferior and superior sheets (6a, 6b) when joining mutually, and said powder becomes paste with steam oozed from wood content when heating pressurization is carried out to the plywood sheet (6) within the press apparatus so that said rough surfaces (8) of the inferior and superior sheets (6a, 6b) are glued mutually.

7. A process for manufacturing a wooden container according to claim 3, wherein powder of starch is applied on at least one of the rough surfaces (8) of the inferior and superior sheets (6a, 6b) when joining mutually, and said powder becomes paste with steam oozed from wood content when heating pressurization is carried out to the plywood sheet (6) within the press apparatus so that said rough surfaces (8) of the inferior and superior sheets (6a, 6b) are glued mutually

8. A process for manufacturing a wooden container according to claim 4, wherein powder of starch is applied on at least one of the rough surfaces (8) of the inferior and superior sheets (6a, 6b) when joining mutually, and said powder becomes paste with steam oozed from wood content when heating pressurization is carried out to the plywood sheet (6) within the press apparatus so that said rough surfaces (8) of the inferior and superior sheets (6a, 6b) are glued mutually

9. A process for manufacturing a wooden container according to claim 5, wherein powder of starch is applied on at least one of the rough surfaces (8) of the inferior and superior sheets (6a, 6b) when joining mutually, and said powder becomes paste with steam oozed from wood content when heating pressurization is carried out to the plywood sheet (6) within the press apparatus so that said rough surfaces (8) of the inferior and superior sheets (6a, 6b) are glued mutually