Folding airtight container

Abstract

 There are disclosed a folding airtight container comprising a board (1) having first and second walls (13, 15), first and second flaps (17, 19), a heat-fusible and airtight flat sheet (3) having substantially rectangular shape and being sticked to the board (1), and sealing pieces (5, 7, 7) provided at the flat sheet (3) at the portion protruded from the board (1) when the flat sheet (3) is sticked to the board (1). There is also disclosed a method for manufacturing the folding airtight container.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention:

[0001] The present invention relates to a folding airtight container to be assembled by a board including plastic corrugated cardboards and a method for manufacturing the same.

2. Prior Art:

[0002] It has been difficult to enhance airtightness of a conventional folding airtight container of this type since materials per se of the airtight container are not heat-fusible and have a large thickness and are hardly fused by heat and pressed. Therefore, the inventor of the present application proposed an airtight container comprising a board and heat-fusible plastic films sticked to the board wherein inner and outer liners of the board are fused for serving as joiing margins while the cores provided at the peripheral side ends of the board (hereinafter referred to as cores) are eliminated.

[0003] However, the conventional folding airtight container has a problem that it takes much time and labour for eliminating the cores.

[0004] In view of the problem set forth above, the present invention has been made to solve the problem and to provide a folding airtight container and a method for manufacturing the same without eliminating the cores.

[0005] To achieve the above object, the folding airtight container according to the present invention is characterized in comprising a box-shaped board having flaps provided at both the top and bottom ends of the front and rear surface walls and left and right side walls, a heat-fusible airtight flat sheet formed substantially in square shape, the flat sheet being sticked to the box-shaped board and protruded from the board for forming sealing pieces at the ends thereof.

[0006] The method for manufacturing the folding airtight container according to the present invention comprises the steps of forming a sheet-shaped board by a corrugating machine, forming the board into a box-shape, forming a flat body protruding from the ends of the box-shaped cardboard, the flat sheet being made of a heat-fusible airtight material and sticking the flat body to at least one inner or outer surface of the board for serving as sealing pieces.

[0007] With the arrangement of the folding airtight container, it is possible to form thin sealing pieces without eliminating the cores of the board and possible to seal each of the sealing pieces by heat-fusing or adhesive agent with assurance and without leaking the container contained therein.

[0008] According to the method for manufacturing the folding airtight container, it is possible to manufacture the folding airtight container set forth above with simplicity.

[0009] The above and other objects, features and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] 

Fig. 1 is a perspective view showing a folding state of a folding airtight container according to the first embodiment of the present invention;

Fig. 2 is a view showing an unfolded state of the folding airtight container of Fig. 1;

Fig. 3 is an enlarged cross sectional view taken along arrows A-A of Fig. 1;

Fig. 4 is a perspective view of a folding airtight container according to a second embodiment of the present invention wherein a cover thereof is opened;

Fig. 5 is an exploded view of the folding airtight container according to the second embodiment of the present invention;

Fig. 6 is a perspective view showing an upper portion of the folding airtight container of Fig. 4 wherein the cover thereof is closed;

Fig. 7 is a perspective view of a folding airtight container according to a third embodiment of the present invention wherein a cover thereof is opened;

Fig. 8 is an exploded view of the folding airtight container according to the third embodiment of the present invention;

Fig. 9 is a perspective view showing an upper portion of the folding airtight container of Fig. 7 wherein the cover thereof is closed;

Fig. 10 is a perspective view of a folding airtight container according to a fourth embodiment of the present invention wherein a cover thereof is opened;

Fig. 11 is an exploded view of the folding airtight container according to the fourth embodiment of the present invention; and

Fig. 12 is a perspective view showing an upper portion of the folding airtight container of Fig. 10 wherein the cover thereof is closed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Embodiment (Figs. 1 to 3):

[0011] A folding airtight container according to a first embodiment of the present invention will be described with reference to Figs. 1 to 3.

[0012] A folding airtight container V comprises a board 1 having substantially rectangular shape and formed in a boxed-shape, a rectangular flat sheet 3 sticked to the inside surface of the box-shaped board 1 (the sticking portion are denoted at one dotted line in Fig. 1), wherein the flat sheet 3 is protruded from the board 1 at the top and bottom ends and one side end thereof and the protruded portions forming sealing pieces 5, 7 and 7. There is protruded a joining margin 8 forming a sealing piece 5a at another side end of the board 1 to which the flat sheet 3 is not sticked. The sealing piece 5a can be peeled off. The board 1 has rules to be folded, described later, but has no cutting lines or perforations. The board 1 has wide front and rear surface walls 13 and 13 at the middle portion thereof and narrow left and right side walls 15 and 15 respectiely defined by upper and lower rules 9 and 9 and four vertical rules 11 wherein flaps 17 and 19 are provided at upper and lower portions of the walls 13 and 15 and continued laterally to each other.

[0013] Inasmuch as it is impossible to fold the flaps 17 and 19 when they are continued laterally and integrated with each other, there are formed isosceles triangles having both sides 21 and bases 9a for demarcating the side walls 15. A kraft is used as the flat sheet 3 to which a heat-fusible polyethylene film is laminated.

[0014] In assembling the folding airtight container, the sealing pieces 5 and 5a provided at both the left and right ends thereof are joined and subjected to heat-fusing, thereafter the resulant heat-fused sealing pieces 5 and 5a are sticked to the front surface wall 13 and the joining margin 8 is sticked thereto (Fig. 3). The folding airtight container assembled in such a square tubular shape is folded flatly and supplied to users. The users fuse the sealing pieces 7 and 7 confronted at the lower portion of the board 1 by heat and fold the flaps 19 for forming triangular bandages 19a while the flaps 17 are closed and the triangular bandage 19a are sticked to the side walls 15. The folding airtight container forms a cover at the upper portion thereof after filling the material therein in the same manner as forming the triangular bandages 19a. The triangular bandages 19a can, as shown in two-dotted lines, be sticked to the flaps 17. In any case, a sticking piece 7a provided at one of the sealing pieces 7 and 7 is fallen down.

[0015] In manufacturing the folding airtight container, the board 1 is manufactured by a corrugating machine which board 1 is formed in a boxed-shape and the flat sheet 3 having an inner surface made of paper and an outer surface made of heat-fusible plastic film is sticked to the board 1 at the inner side surface thereof. The flat sheet 3 may be made of heat-fusible plastic films at both surfaces thereof.

Second Embodiment (Figs. 4 to 6):

[0016] A folding airtight container according to a second embodiment will be described with reference to Figs. 4 to 6. Elements same as those in the first embodiment have same numerals and explanation thereof is omitted.

[0017] In forming a cover of the airtight container, the flaps 19 of the left and right side walls 15 are positioned under the flaps 17 of the front and rear walls 13 so that the flaps 19 can form the isosceles triangles and connection pieces 23 and 23 for connecting the flaps 19 with the flaps 17 are formed at the lower ends of the flaps 19 and the flaps 17 so that the flaps 19 and 17 are interlocked with each other when they are folded. One of the flaps 17 has a non-sticking portion 22 at the tip end thereof to which the flat sheet 3 is not sticked. There is defined a sticking piece 7a in one of the sealing pieces 7 and 7 which piece 7a can be inserted into the gap between the non-sticking portion 22 and the flat sheet 3 so that a tape 24 is liable to stick to the upper portion of the non-sticking portion 22 different from the case where the sticking piece 7a is exposed.

[0018] Cutting slits 26 are formed between the flaps 17 and 18 same as type A of the manufacturing method of the corrugated cardboards according to Japanese Industrial Standards. The flaps 17 and 19 can be peeled off from the flat sheet 3 without impeding the formation of the lower cover by the flat sheet 3 while only the flaps 19 can stick to the flat sheet 3 at the isosceles triangular bandage 19a formed by the flaps 19 which isosceles triangular bandage 19a having the bases thereof by demarcating line 9a demarcating the side walls 15.

[0019] There are provided vertical rules 25 and 25 in both the central portions of the side walls 14 and the flaps 19 so that they can be folded flat from the tubular shapes. When the folding airtight container is supplied to the users, since the folding airtight container is folded while the both ends sealing pieces 5 and 5 and the lower end sealing pieces 7 and 7 are sticked to each other (in this case, the lower end sealing pieces 7 can be previously sticked to each other and foldable inside and outside thereof).

Third Embodiment (Figs. 7 to 9):

[0020] A folding airtight container according to a third embodiment will be described with reference to Figs. 7 to 9. Elements same as those in the first and second embodiments have same numerals and explanation thereof is omitted.

[0021] The arrangements of the board 1 and the flat sheet 3 are substantially same as those of the first embodiment excepting that there are provided vertical rules 25 for folding purpose. The relation between the flat sheet 3 and the flaps 19 of the left and right side walls 15 and the flaps 17 of the front and rear walls 13 are as follows. The flaps 17 can be peeled off from the flat sheet 3 so that the flaps 19 are folded under the flaps 17 and the flaps 19 are sticked to the flat sheet 3 at the isosceles triangular bandage 19a formed by the flaps 19 which isosceles triangular bandage 19a having the bases thereof by demarcating line 9a demarcating the side walls 15.

Fourth Embodiment (Figs. 10 to 12):

[0022] A folding airtight container according to a fourth embodiment will be described with reference to Figs. 10 to 12. Elements same as those in the first to third embodiments have same numerals and explanation thereof is omitted.

[0023] An arrangement of the folding airtight container of the fourth embodiment is substantially same as that of the folding airtight container of the second embodiment excepting that the flat sheet 3 is formed in a bag shape and sticked partially to the board 1. With such an arrangement, the board 1 can be reused by peeling off the used flat sheet 3 and substituted by new flat sheet 3.

[0024] As described above in detail, the folding airtight containers according to the first to fourth embodiments have the following advantages. Firstly, it is possible to form thin sealing pieces to which pressure is easily applied without eliminating the cores of the board. Secondly, it is possible to carry out the sealing of the airtight container which enhances the packing operation with assuarance at the work site by connecting the sealing pieces by heat-fusing or the adhesive agent.

[0025] According to the method according to the present invention, it is possible to manufacture the folding airtight container with ease and simlicity so that the folding airtight container can be adapted for mass production with low cost.

[0026] The board set forth in the first to fourth embodiments of the present invention is typically represented by a corrugated cardboard including a plastic corrugated board but it may include a thick paper, a cardboard, a resin sheet, a resin plate, a resin board, a plywood and a fiber board and the like.

[0027] Although the invention has been described in its preferred form with a certain degree of particularity, it is to be understood that many variations and changes are possible in the invention without departing from the scope thereof.

[0028] The features disclosed in the foregoing description, in the claims and/or in the accompanying drawings may, both separately and in any combination thereof, be material for realising the invention in diverse forms thereof.

Claims

1. A folding airtight container compring:
   a board (1) having front and rear walls (13, 13), left and right side walls (15, 15) continued from the front and rear walls (13, 13), first flaps (17, 17) provided at the upper and lower ends of the front and rear walls (13, 13) and second flaps (19, 19) provided at the upper and lower ends of the left and right side walls (15, 15);
   a heat-fusible and airtight flat sheet (3) having substantially rectangular shape being sticked to the board (1); and
   sealing pieces (5, 7, 7) provided at the flat sheet (3) at the portion protruded from the board (1) when the flat sheet (3) is sticked to the board (1).

2. A folding airtight container according to Claim 1, wherein the flat sheet (3) has an inner surface made of paper and an outer surface made of heat-fusible and airtight plastic film.

3. A folding airtight container according to Claim 1, wherein the board (1) has an adjoining piece (8) for forming a sealing piece to which the flat sheet (3) is not sticked.

4. A folding airtight container according to Claim 1, wherein the first and second flaps (17, 19) are continued laterally and the second flaps (19, 19) form isosceles triangular bandages (19a) having bases (9a) demarcating side walls (15, 15) which bandages (19a) can be sticked to the side walls (15, 15).

5. A folding airtight container according to Claim 1, wherein the isosceles triangular bandages (19a) can be sticked to the first flaps (17, 17).

6. A folding airtight container according to Claim 1, wherein the second flaps (19, 19) form isosceles triangular bandages (19a) having bases (9a) demarcating side walls (15, 15) which bandages (19a) can be sticked to the side walls (15, 15), and connection pieces (23, 23) for connecting the first flaps (17, 17) to the second flaps (19, 19) are formed at the lower ends of the bases (9a) of the isosceles triangular bandages (19a).

7. A folding airtight container according to Claim 1, wherein the first flaps (17, 17) are not sticked to the flat sheet (3) and the flaps (19, 19) are sticked to the flat sheet (3) at the isosceles triangular portions (19a) formed by the flaps (19) which isosceles triangular bandages (19a) having the bases (9a) thereof by demarcating lines (9a) demarcating the side walls (15, 15).

8. A folding airtight container according to Claim 1, wherein the flat sheet (3) comprises a bag which is detachably sticked to the board (1).

9. A folding airtight container according to Claim 1, wherein the side walls (15, 15) and the second flaps (19, 19) continued from the side walls (15, 15) have respectively at the central portions thereof vertical rules (25, 25) which can be foled inside or outside the board (1) when the board (1) is assembled.

10. A method for manufacturing a folding airtight container comprising the steps of:
   forming a sheet shaped board (1) by a corrugating machine;
   forming the boad (1) into a box-shape;
   forming a flat sheet (3) having an inner surface made of paper and an outer surface made of heat-fusible and airtight plastic;
   sticking the inner surface of the flat sheet (3) to at least one of the inner or outer surface of the board (1) so that the flat sheet (3) can be protruded from the board (1); and
   serving the portion protruded from the board (1) as sealing pieces.

Drawing