JPH05246418A - Paper container and production thereof - Google Patents

Abstract

PURPOSE:To make up a paper container once from its blank and then bring it back into a folding form, so that it can be reformed easily and quickly upon packing with its contents by a method wherein a pair of inner bottom plates are attached to the inner surfaces of a pair of outer bottom plates and a plurality of folding parts are formed at the required places of the bottom plates. CONSTITUTION:A paper container 1 consists of four side plates 1a-1d formed into a square shape when they are viewed from top with four bottom plates 1e-1h folded inwards from the lower ends of the side plates 1a-1d, respectively. To accomplish this, the two bottom plates 1e and 1d are first folded inwards and the two bottom plates 1f and 1h are then folded inwards over the two bottom plates 1e and 1d, which are brought into contact with the inner surfaces of the bottom plates 1f and 1h and attached thereto at two contact faces in the diagonal direction. At each attaching place of the bottom plate 1, folding parts P4 and P6 are formed diagonally between the end part of the attaching place and the corner of the bottom plate. Curved folding parts P5 are formed from the sides at the place of being left unattached but contacting of the two bottom plates 1e and 1f coming outside to their forward ends to face outward the open sides of the bottom plates 1e and 1f.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foldable paper container and a manufacturing method thereof.

[0002]

2. Description of the Related Art In general, a corrugated paper container, which is lightweight, has a low manufacturing cost and is easy to handle, is often used to store and convey various products such as fruits and vegetables and industrial products. Conventionally, when manufacturing such a paper container in a manufacturing plant, as shown in FIG. 19, one corrugated cardboard sheet forming the paper container 1 is placed on top of the side plates 1a, 1b, 1c, 1d and the upper lids 1i, 1j, 1k. , 1 m, and side plates 1a, 1
b, 1c, 1d are integrally cut into a shape having bottom plates 1e, 1f, 1g, 1h under the lower parts, subsequently, side edges of the side plate 1a and side plates 1d are bonded, and , The bending portions P1 and P1 formed between the side plate 1a and the side plate 1b and between the side plate 1c and the side plate 1d are bent to form the paper container 1
It was delivered to the boxing factory in this shape, which is not bulky and is flat and easy to transport. P2, P in the figure
Reference numeral 3 is a bent portion for the upper lid and the lower lid, which are formed in advance at the paper container manufacturing factory.

As shown in FIG. 20, in a cartoning factory, a folding paperboard 1 having such a folded shape is folded inward by folding two bottom plates 1e and 1g which are located in opposite directions using a bending portion P2. Bent, then the other bottom plate 1f, 1h is bent inward, and the side plates 1a, 1c are covered with adhesive tape V so as to cover between the tips of the long bottom plates 1f, 1h.
Alternatively, long bottom plates 1f and 1h and short bottom plates 1e and 1g.
The box-shaped paper container 1 can be assembled by adhering the contact surface portion with and with an adhesive, or by bottoming with staples.
Although a step is formed between the short bottom plates 1e and 1g forming the inner bottom of the paper container 1, a spacer S made of a corrugated cardboard sheet or a styrofoam sheet is housed in the step to make the inner bottom flat. When the products are packed in the paper container 1 assembled in this way, the upper lids 1i ... 1n are bent using the bent portions P2 and are sealed.

[0004]

However, as described above, in order to assemble the paper container 1 on the packaging factory side, the personnel required for the packaging factory side, the time required for the packaging, and the space required for the assembly are secured. However, it is not easy to secure these.
Moreover, if the paper container 1 is assembled according to the flow of the boxing work, the assembling time of the paper container 1 will not be in time for the boxing,
Affects the packing process flow. For this purpose, a required number or more of paper containers 1 ... Are assembled and temporarily stored, and the stored paper containers 1 ... are sequentially taken out for boxing work. Is bulky and requires a large space for storage.
In particular, in order to store a large number of paper containers 1, side plates 1a, 1
b, 1c, 1d, the upper lids 1i, 1j, which are erected on top of
When the paper containers 1 are sequentially stacked between 1k and 1m, cracks often occur at the base ends of the upper lids 1i, 1j, 1k, and 1m of the paper containers 1, and the stacked paper containers 1 are often broken and damaged.

The present invention has been made in view of such circumstances, and after assembling the paper container factory so that it can be folded, it is once folded and delivered to a boxing factory. It is an object of the present invention to provide a paper container and a manufacturing method thereof which can be assembled with one touch and in an instant, reduce the assembly time, personnel and space on the side of the box packing site, and do not require a large storage space.

[0006]

The first aspect of the present invention proposed to achieve the above object is, as its first aspect, that the shape surrounded by the four side plates is a quadrangular shape in plan view, and the inside of the lower end of the side plate is formed. In a paper container having four bottom plates formed by bending in two directions, two bottom plates to be located inside of the four bottom plates are in contact with inner surfaces of two bottom plates to be located outside. Of the four contact surfaces, the contact surfaces of the two bottom plates located in one of the diagonal directions of the quadrangular shape are adhered, and the bent portion is diagonally bent with the base end of the adhered part of the bottom plate as one end. Is formed, and a curved bent portion for directing the open side end of the bottom plate to the outside is provided at a position from the side edge of the portion of the two bottom plates positioned on the outer side which are not adhered to each other and are in contact with each other to the tip side. It is characterized in that each is formed.

As the second aspect, in the method for manufacturing a paper container having a shape in which a shape surrounded by four side plates has a rectangular shape in a plan view, and four bottom plates are formed by bending the side plates inward from the lower end thereof, Of the four bottom plates, the two bottom plates to be located inside are in contact with the inner surfaces of the two bottom plates to be located outside and are located in one of the four diagonal directions of the square shape in the diagonal direction. Adhere the contact surface of the bottom plate at a certain position, and a bent portion is formed on a diagonal line having one end at the base end of the bonded portion of the bottom plate, and should be positioned outside 2
It is characterized in that curved bent portions for directing the open side ends of the bottom plates to the outside are respectively formed at positions from the side edges of the contacting surfaces of the bottom plates without adhering to the tip edges.

As part 3, in a paper container provided with four bottom plates formed by being bent inward from a lower end of the side plates, the shape surrounded by the four side plates is a quadrilateral in plan view, and the four bottom plates are provided. Two bottom plates facing each other on one side are in contact with inner surfaces of two bottom plates facing each other on the other side, and two of the four contacted bottom plates are located in one diagonal direction of the square shape. The contact surface portion of the bottom plate is adhered, and a bent portion for directing the open side end of the bottom plate outward is formed at a position from the middle of the side edge of the contact surface portion of the bottom plate to the middle of the tip side. Characterize.

As the fourth aspect, in the method for manufacturing a paper container which has a shape surrounded by four side plates and has a quadrilateral shape in a plan view, and which is provided with four bottom plates bent inward from the lower ends of the side plates, Two bottom plates facing each other on one side of the one bottom plate are in contact with the inner surfaces of the two bottom plates facing each other on the other side, and two of the four contacting positions are located in one diagonal direction of the square shape. Bonding the contact surface portion of the bottom plate, and forming a bent portion for directing the open side end of the bottom plate to the outside at a position from near the tip of the side of the bonded portion of the bottom plate to near the end of the tip side. Characterize.

Fifth, the bottom plate is folded by applying a force inward from each of the diagonal directions which are not adhered,
In addition, after folding, the base plate is restored to its original shape by applying an inward force from each diagonal direction to which the bottom plate is adhered.

[0011]

According to the paper container and the method of manufacturing the same of the present invention, after the paper container is manufactured in the manufacturing factory and once assembled, the paper container is folded and delivered to the boxing factory. , It can be instantly restored to the original assembled shape and used.

That is, in a paper container manufacturing plant, the four side plates forming the paper container are bent in a quadrangular shape in a plan view, and then one of the two bottom plates located in the opposite direction is bent inward to align the tips, and further. The other two bottom plates are bent inward to be brought into contact with the bottom plate, and two of the four contacted faces which are diagonally positioned are bonded to each other to assemble a paper container.

When a force is applied inwardly from the diagonal direction where the bottom plate is not adhered to the assembled paper container to bend the bent portions of the two side plates in the diagonal direction on the adhered side into acute angles, respectively. , The adhesive part of the bottom plate bends upwards,
At the same time, the open side end of the bottom plate located outside of the bottom plate is
The outer surface of the bottom plate located inside thereof is abutted and bent outward from the bent portion, and the tips of the four bottom plates rise upward to fold the entire paper container, thus forming a shape suitable for transportation and storage.

Further, subsequently, when a box is packed in a box factory, a force is applied inwardly from both ends of the folded paper container, so that the flatly folded side plate returns to a square shape in plan view, At the same time, the adhesive portion of the bottom plate that has been bent upward is pulled back downward and returns to its original position. At the same time, since the open end of the bottom plate located on the outer side is slightly bent outward when folded, the open end of the bottom plate located on the outer side smoothly moves along the outer surface of the bottom plate located on the inner side. Return to the position.

The open side end of the bottom plate according to the first aspect is formed such that the entire paper container including the bottom plate is formed of a strong cardboard even if it is bent outward in the folding and restoring process, and the bending is performed. Since the part has an arcuate shape that can be easily restored, when the pressing force in the direction of the bottom plate that comes into contact is released, the part immediately returns to the original flat shape. Although the open side end of the bottom plate according to claim 3 remains bent to the outside to some extent, the bent part is made smaller so that it does not affect the accommodation of products and the handling of paper containers.

[0016]

Embodiments of the paper container and the manufacturing method thereof according to the present invention will be described below with reference to the accompanying drawings. As for the paper container and the manufacturing method thereof of the present invention, there are two kinds of configurations in which the shape of the bent portion formed at the open side end of the bottom plate of the paper container is a curved shape and a linear shape. In both of the latter cases, there are those in which the bent portion is formed on the two short bottom plates and those on which the bent portions are formed in the two long bottom plates.

First, a paper container in which a curved bent portion is formed at the open side end of a short two-width bottom plate and a method for manufacturing the same will be described. FIG. 1 is a bottom perspective view of a paper container according to a first embodiment of the present invention in a state in which the paper container is bent to some extent, FIG. 2 is a front view of a cardboard sheet forming the paper container, and FIG. 3 is a bottom view showing a method of assembling the paper container. FIG. 4 is a bottom perspective view showing a state after assembling the paper container, and FIG. 5 is a partially cutaway perspective view of the paper container. As shown in FIGS. 1 to 5, a paper container 1 of the present invention
Is formed by cutting and assembling a corrugated cardboard sheet, especially a single-stage corrugated cardboard sheet that is easy to bend and form. It is also possible to form the resin sheet material that is easy to process.

As shown in FIG. 2, in order to manufacture the paper container 1 of the present invention, first, one corrugated cardboard sheet is placed on the side of the rectangular side plate 1a of short width and the rectangular side plate 1b of long width is positioned. In addition, a side plate 1c having the same shape as the side plate 1a is located on the other side of the long rectangular side plate 1b, and a side plate 1d having the same shape as the side plate 1d is located on the other side of the side plate 1c. In addition, lid plates 1i, 1j, 1k, 1m are respectively located above the side plates 1a, 1b, 1c, 1d, and bottom plates 1e, 1 are provided under the side plates 1a, 1b, 1c, 1d, respectively.
f, 1g, 1n are located, and subsequently, a vertically long ear plate 1 in which a projecting end 1n ′ is projected upward at the outer end of the side plate 1a.
Cut into a shape in which n is located.

At the time of this cutting, the upper lids 1 adjacent to each other are cut.
between i and the top cover 1j, between the top cover 1j and the top cover 1k, between the top cover 1k and the top cover 1m, and between the bottom plate 1e and the bottom plate 1f,
The bottom plate 1f and the bottom plate 1g and the bottom plate 1g and the bottom plate 1h are cut out and cut. The size of the corrugated cardboard sheet thus cut depends on the shape and size of the paper container to be formed, but as will be described later, at least the long width lid plates 1j and 1m and the long width bottom plates 1f and 1h are formed. When the upper lid and the lower lid are respectively bent to the inner surface side and the upper lid and the lower lid are closed, there is no gap and they do not overlap with each other, and both ends are in contact with each other.

Then, the inner side is bent along the boundary lines between the adjacent side plates 1a and 1b, between the side plates 1b and 1c, and between the side plates 1c and 11d. The parts P1 ... Are formed by pressing, and at the same time, between the side plate 1a and the upper lid 1i, between the side plate 1b and the upper lid 1j,
A bent portion P2 that bends inward on the boundary between the side plate 1c and the upper lid 1k and between the side plate 1d and the upper lid 1m.
・ ・ Pressed to form. Also, the side plate 1a and the bottom plate 1
e, the side plate 1b and the bottom plate 1f, the side plate 1c and the bottom plate 1g, and the side plate 1d and the bottom plate 1h on the respective boundary lines, the bent portions P3 ... Is formed by pressing. Further, a bent portion P4 (P) that bends toward the inner surface also on a line from the center of the outer long side of the short bottom plate 1e (1g) to the end of the bent portion between the side plates 1a, 1b (1c, 1d).
4) is formed.

Then, bent portions P6 and P6 which are bent toward the inner surface side are formed at positions corresponding to the bent portions P4 and P4 on the long bottom plates 1f and 1h. Further, of the four contact surface portions, the open side ends of the two bottom plates 1e and 1g, which are located outside, are connected to the open side ends of the two bottom plates 1e and 1g from the side sides of the open ends which are not adhered to the tip side extending diagonally. The curved bent portions P5 and P5 that face toward each other are formed by pressing. In addition to this, bending portions P7 ... Bent to the inner surface are formed by pressing on the boundary line between the side plate 1a and the ear 1n.

Next, the bent portion P of the long bottom plates 1f and 1h.
An adhesive agent B is applied to the outer surface of the quadrangular surface having the diagonal line of 6, P6 and the surfaces of the ears 1n and the protruding ends 1n 'thereof. Note that the adhesive B is not applied to the long bottom plates 1f and 1h,
Long bottom plates 1f and 1h and short bottom plates 1e and 1g adjacent to each other
It may be applied to the corresponding inner surface on one side or to both of these surfaces.

Subsequently, as shown in FIG. 3, the side plates 1a, 1b, 1c and 1d are formed along the bent portion P1 and the bent portion P
7 is bent so as to surround the inner surface, and the outer surface of the ear 1n at the end of the side plate 1a coated with the adhesive B is used as the inner surface of the side plate 1d.
The protruding ends 1n ′ of the ears 1n are attached to the inner surfaces of the side ends of the upper lid 1m, respectively, and assembled so that the shape surrounded by the four side plates 1a, 1b, 1c, 1d becomes a rectangular shape in plan view.

Subsequently, as shown in FIGS. 4 and 5, the long bottom plates 1f and 1h are bent inward from the bent portions P3 and P3 to align the tips of the bottom plates 1f and 1h, and then the short widths of the short plates 1f and 1h. Bottom plate 1
e and 1g are bent inward from the bent portions P3 and P3, and are adhered to the mutual coated surface of the adhesive B.

The box-shaped paper container 1 can be folded, and the folding method will be described in detail. 6 and 7 are partially cutaway perspective views showing the folding and restoring method of the paper container, and FIG. 8 is an overall perspective view showing the folded state of the paper container, and FIGS. The same parts as those in FIG. 5 are designated by the same reference numerals.

First, from the shapes shown in FIGS. 4 and 5,
When a force is applied inward from both base ends of two diagonally unbonded bases among the four positions where the short width bottom plates 1e and 1g and the long width bottom plates 1f and 1h are in contact with each other, FIG. And FIG.
As shown in FIG. 2, two side plates 1a, 1b and 1 having two short widths and long widths, which are diagonally located on the bonded side, are provided.
The bent portions P1 and P1 of c and 1d are bent at an acute angle, and at the same time, the bent portions P4 and P4 of the bonded portions of the short width bottom plates 1e and 1g are the corresponding portions of the long width bottom plates 1f and 1h. Along with that, it bends upward (inward). At the same time, the open side ends of the short width bottom plates 1e and 1g are bottom plates 1f and 1h.
The arc-shaped bent portions P5, P5 bend outward in contact with the outer surface of the bottom plate 1f, 1h and the short bottom plates 1e, 1e, which are closed as shown in FIGS. The tip of 1 g retreats and rises to open the bottom surface of the paper container 1, and finally, as shown in FIG. 8, the entire paper container 1 can be folded into a substantially flat shape. In addition, when the paper containers 1 thus compactly folded are bundled with a certain number of pieces with a string, a large number of paper containers 1 can be stored at one time, and the number can be easily confirmed.

Subsequently, in order to restore the folded paper container 1 to the original shape, both side edges of the paper container 1 which is folded and has an acute angle, that is, the short width bottom plates 1e and 1g and the long width bottom plate 1 are formed.
When a force is applied inward from the diagonal direction where f and 1h are adhered, the short side plates 1a and 1c and the long side plate 1 are
b and 1d are restored from the shape shown in FIG. 8 in the direction of the rectangular shape in plan view shown in FIGS. 4 and 5. At the same time, the portions of the short bottom plates 1e, 1g and the long bottom plates 1f, 1h that are bent upward are bonded to each other as shown in FIGS. 1 and 2, and the side plates 1a, 1b, 1c. , 1d are pulled back as they are restored, so that the short bottom plates 1e and 1g and the long bottom plates 1f and 1h that have risen upward are raised.
Tip moves downward.

Since the open ends of the short bottom plates 1e and 1g are bent slightly outward from the curved bent portions P5 and P5 as described above, the open ends are It returns to the original position along the outer surface of the bottom plates 1f, 1h without coming into contact with the side edges of the long bottom plates 1f, 1h and being located on the inner surface side of the bottom plates 1f, 1h. Moreover, the entire paper container 1 including the bottom plates 1e and 1g is formed of a strong cardboard, and further, the bent portion P5,
Since P5 has a curved shape that is easy to return to its original shape when bent, the open side ends of the short width bottom plates 1e, 1g after returning do not hang downward from the bent portions P5, P5. The original restoring force immediately restores the original flat plate shape. The inner bottom of the paper container 1 restored to its original shape in this way is
As described above, since the front ends of the long bottom plates 1f and 1h are aligned, they are flat surfaces.

The paper container 1 restored to its original assembled shape in this way has a long bottom plate 1 having a tip inside the bottom surface thereof.
Since it is formed flat by f and 1h, the product can be accommodated at a stable upper end, and the spacer which is required in the conventional paper container is not necessary. In this way, the paper container 1
After accommodating the commodities therein, the short-width upper lids 1i and 1k are folded inward and closed, and then the long-width upper lids 1j and 1m are folded inward and closed. In addition, since the side plate 1a end and the side plate 1d end are adhered by the adhesive B, the strength of this part should be weakened originally, but the protruding end 1n 'of the ear part 1n has a long width of the upper lid 1m. Since this is also adhered, this portion is reinforced so that the end of the side plate 1a and the end of the side plate 1d are not easily separated from each other.

Next, a paper container in which a curved bent portion is formed at the open end of a long bottom plate and a method for manufacturing the paper container will be described. FIG. 9 is a bottom perspective view of the paper container according to the second embodiment of the present invention in a state in which the paper container is bent to some extent, FIG. 10 is a front view of a corrugated paper sheet forming the paper container, and FIG. 11 is a bottom view showing an assembling method of the paper container. FIG. 12 is a bottom perspective view showing the assembled state of the paper container, and FIG. 13 is a partially cutaway perspective view of the paper container.

As shown in FIG. 10, in order to manufacture the paper container 1 of the present invention, first, as in the case described above, one corrugated cardboard sheet is long sideways to the side of the rectangular side plate 1a having a short width. The rectangular side plate 1b of FIG.
A side plate 1c having the same shape as the side plate 1a is located on the other side of b, and a side plate 1d having the same shape as the side plate 1d is located on the other side of the side plate 1c, and the side plates 1a, 1b, 1c. ，
The lid plates 1i, 1j, 1k and 1m are respectively located above the 1d, and the bottom plates 1e, 1f, 1g and 1n are respectively located below the respective side plates 1a, 1b, 1c and 1d, and the side plates are subsequently continued. The protruding end 1n 'is cut into a shape in which a vertically long ear plate 1n is located at the outer end of 1a.

At the time of this cutting, the upper lids 1 adjacent to each other are cut.
between i and the top cover 1j, between the top cover 1j and the top cover 1k, between the top cover 1k and the top cover 1m, and between the bottom plate 1e and the bottom plate 1f,
The bottom plate 1f and the bottom plate 1g and the bottom plate 1g and the bottom plate 1h are cut out and cut. The size of the corrugated cardboard sheet thus cut depends on the shape and size of the paper container to be formed, but as will be described later, at least the long-width lid plates 1j and 1m and the long-width bottom plates 1f and 1h are Each of them is bent to the inner surface side and has a size such that when the upper lid and the lower lid are closed, there is no gap and they do not overlap each other, and the tips of both can abut.

Next, the inner surface is bent along the boundary lines between the side plates 1a and 1b, the side plates 1b and 1c, and the side plates 1c and 11d which are adjacent to each other. The parts P1 ... Are formed by pressing, and at the same time, between the side plate 1a and the upper lid 1i, between the side plate 1b and the upper lid 1j,
A bent portion P2 that bends inward on the boundary between the side plate 1c and the upper lid 1k and between the side plate 1d and the upper lid 1m.
・ ・ Pressed to form. Also, the side plate 1a and the bottom plate 1
e, the side plate 1b and the bottom plate 1f, the side plate 1c and the bottom plate 1g, and the side plate 1d and the bottom plate 1h on the respective boundary lines, the bent portions P3 ... Is formed by pressing.

Further, a bent portion that bends inward on the line from the center of the long side of the outer edge of the short width bottom plate 1e (1g) to the end of the bent portion between the side plates 1a, 1b (1c, 1d). P4 (P
4) is formed. Then, bent portions P6 and P6 that are bent inward are formed at positions corresponding to the bent portions P4 and P4 on the long width bottom plates 1f and 1h. Further, of the four contact surface portions, the two long bottom plates 1f, 1 located on the outer side.
Curved bent portions P5, P with the open side end of the bottom plate facing outward from the side of the unbonded portion to the tip side
5 are pressed and formed. In addition to this,
On the boundary line between the side plate 1a and the ear 1n, bent portions P7 ... Bent to the inner surface are formed by pressing.

Then, the bent portions P of the short width bottom plates 1e and 1g.
6, the adhesive B is applied to the half outer surface of the P6 forming side and the surfaces of the ears 1n and the protruding ends 1n 'thereof. The adhesive B may not be applied to the short width bottom plates 1e and 1g, but may be applied to the corresponding inner surfaces of the short width bottom plates 1e and 1g and the adjacent long width bottom plates 1f and 1h, or both surfaces. May be applied to.

Then, as shown in FIG. 11, the bent portion P1
The side plates 1a, 1b, 1c, 1d are bent along with the bent portion P7 so as to surround the inner surface, and the outer surface of the ear 1n at the end of the side plate 1a coated with the adhesive B is applied to the inner surface of the side plate 1d. The protruding ends 1n ′ of the ears 1n are attached to the inner surfaces of the side ends of the upper lid 1m, respectively, and assembled so that the shape surrounded by the four side plates 1a, 1b, 1c, 1d becomes a rectangular shape in plan view.

Then, as shown in FIGS. 12 and 13,
The short bottom plates 1e and 1g are bent inward from the bent portions P3 and P3, and then the long bottom plates 1f and 1h are bent portions P3 and P3.
Bend inward from the bottom to align the tips of the bottom plates 1f, 1h,
The adhesive B is adhered according to the mutual application surface.

The box-shaped paper container 1 can be folded, and the folding method will be described in detail. 14 and 15 are partially cutaway perspective views showing the folding and restoring method of the paper container, and FIG. 16 is an overall perspective view showing the folded state of the paper container.
In FIG. 1, the same parts as those in FIGS. 1 to 13 are designated by the same reference numerals.

First, from the shapes shown in FIG. 12 and FIG. 13, when a force is applied inward from both base end portions of two of the four contact surfaces which are not adhered and are diagonally bonded,
As shown in FIGS. 14 and 15, two side plates 1 having a short width and a long width, which are located in two diagonal positions on the bonded side.
The bent portions P1, P1 of a, 1b and 1c, 1d are bent at an acute angle, and at the same time, the bent portions P4, P4 of the bonded portions of the short width bottom plates 1e, 1g are changed to the long width bottom plate 1f, 1
Bends upward (inward) along with the corresponding part of h.

At the same time, the open side ends of the long bottom plates 1f and 1h come into contact with the outer surfaces of the short bottom plates 1e and 1g to bend the curved bent portions P5 and P5 outwardly, as shown in FIG. Figure 1
4, the closed long bottom plates 1f and 1h and the short bottom plates 1e and 1g are retracted and risen to open the bottom of the paper container 1, and finally, as shown in FIG. In addition, the entire paper container 1 can be folded into a substantially flat shape. In addition, when the paper containers 1 thus compactly folded are bundled with a certain number of pieces with a string, a large number of paper containers 1 can be stored at one time, and the number can be easily confirmed.

Subsequently, in order to restore the folded paper container 1 to the original shape, both side ends of the paper container 1 which is folded and has an acute angle, that is, the short width bottom plates 1e and 1g and the long width bottom plate 1 are used.
When a force is applied inward from the diagonal direction where f and 1h are adhered, the short side plates 1a and 1c and the long side plate 1 are
b and 1d are restored from the shape shown in FIG. 16 to the rectangular shape in plan view shown in FIGS. 12 and 13. At the same time, the short bottom plates 1e, 1 which are bent upwards
As shown in FIGS. 9 and 10, the side portions 1a, 1b, 1 of the g and the long bottom plates 1f, 1h are adhered to each other.
Since the c and 1d are pulled back with the restoration, the short width bottom plates 1e and 1g and the long width bottom plates 1f and 1h that have risen upward move downward.

Since the open ends of the long bottom plates 1f and 1h are bent outward slightly from the curved bent portions P5 and P5 as described above, the open ends are It returns to the original position along the outer surface of the bottom plates 1e, 1g without contacting the side edges of the short width plates 1e, 1g and without being located on the inner surface side of the bottom plates 1e, 1g. Moreover, the entire paper container 1 including the bottom plates 1f and 1h is formed of a strong cardboard, and the bent portions P5 and P5 are further formed.
Since it has a curved shape that allows it to return to its original shape when bent, the open side ends of the long bottom plates 1f and 1h after returning immediately restore to their original flat plate shape due to their own restoring force. Moreover, since the bent portion is small, it does not hang down from the bent portions P5 and P5. For this reason, even after the products are stored in the paper container 1,
It does not hinder the handling of. As described above, the inner bottom of the paper container 1 restored to the original shape is a flat surface because the front ends of the long bottom plates 1f and 1h are aligned.

Next, a paper container in which a bent portion is formed at the open side end of the two short bottom plates and a method of manufacturing the paper container will be described. 17 is a bottom perspective view showing a state in which the paper container according to the third embodiment of the present invention is bent and contracted to some extent, and FIG. 18 is a bottom perspective view showing the assembled paper container.
In FIG. 6, the same parts as those in FIGS. 1 to 16 are designated by the same reference numerals. In order to manufacture the paper container of the present invention as shown in FIGS. 17 and 18, one corrugated board sheet cut in the same manner as shown in FIG. 2 is folded in the same manner as shown in FIG. Curved parts P1 to P4 and P6
P7 is pressed, and two short width bottom plates 1e, 1
g of the long bottom plates 1f and 1h that do not adhere to each other and reach the outer surface of the bottom surface 1f, 1h from the midpoint of the side edge to the midpoint of the tip edge. The bent portions P5 and P5 are formed respectively.

Subsequently, the adhesive B is applied to the corresponding portions similar to those shown in FIG.
As in the case shown in, the cardboard sheet is assembled into the paper container 1. In order to fold the box-shaped paper container 1 as described above, first, from the shape shown in FIG. 18, inward from both base ends of two of the four contact surfaces which are not adhered and are diagonally bonded. When a force is applied to, as shown in FIG. 17, the tip ends of the closed long bottom plates 1f and 1h and the short width bottom plates 1e and 1g retreat and rise to open the bottom surface of the paper container 1, and finally. Can fold the entire paper container 1 into a substantially flat shape.

At the time of folding, the bent portions P4 and P4 of the portions where the short width bottom plates 1e and 1g are adhered to each other.
Is above (inward) with the corresponding parts of the long bottom plates 1f and 1h
Bends in the direction of the bottom, and at the same time, has a short bottom plate 1
A bent portion P in which the open side ends of e and 1g are in contact with the outer surfaces of the long bottom plates 1f and 1h to form the short bottom plates 1e and 1g.
5 and P5 are bent outwardly and have short bottom plates 1e and 1g.
It is possible to fold the open side ends of the bottom plates 1f and 1h along the outer surfaces thereof. By bundling a fixed number of the paper containers 1 folded in this way with a string, a large number of paper containers 1 can be stored at one time, and the number can be easily confirmed.

Subsequently, in order to restore the folded paper container 1 to the original shape, both side edges of the paper container 1 which is folded and has an acute angle, that is, the short width bottom plates 1e and 1g and the long width bottom plate 1f,
When a force is applied inward from the diagonal direction where 1h and 1h are adhered, short side plates 1a, 1c and long side plates 1b, 1
d is restored to a direction in which it has a rectangular shape in plan view shown in FIG. 18 through the shape shown in FIG. At the same time, the bonded portions of the short bottom plates 1e and 1g bent upward and the long bottom plates 1f and 1h are bonded to the side plates 1a and 1h.
As the b, 1c, 1d are restored downward, the short bottom plates 1e, 1g and the long bottom plates 1f, 1h rising upward move downward.

Since the open side ends of the short width bottom plates 1e and 1g are bent slightly outward from the bent portions P5 and P5 as described above, the open side ends have a long width. It returns to its original position along the outer surface of the bottom plates 1f, 1h without contacting the side edges of the bottom plates 1f, 1h and without being located on the inner surface side of the bottom plates 1f, 1h. Since the inside of the bottom surface of the paper container 1 restored to the original assembled shape is formed by the bottom plates 1f and 1h having the long width and the tip, the product can be stored at the stable upper end. The open side ends of the short width bottom plates 1e and 1g after returning to the original shape remain with the bent portions P5 and P5 slightly bent in a triangular shape, but the bent ends Since the portion is small, it does not become an obstacle even after the product is stored in the paper container 1 and in the handling of the paper container 1.

In the paper container 1 described above with reference to FIGS. 17 and 8, the bent portions P5 and P5 are formed on the short width bottom plates 1e and 1g which are in contact with the outer surfaces of the long width bottom plates 1f and 1h. Similarly, if the paper container 1 is configured such that the long bottom plates 1f and 1h are in contact with the outer surfaces of the short bottom plates 1e and 1g, the same bent portion P5 as in the case described above is used. P5 is a bottom plate 1e having a short width, and a bottom plate 1f having a long width is in contact with the outer surfaces of the bottom plates 1e and 1g.
Bent portions P5 and P5 that bend the tip corners of the open side ends outward are formed on short lines from the vicinity of the tip of the side edge of 1h to the vicinity of the end of the tip side.

The product is housed in the paper container 1 assembled as shown in each of the above embodiments, and then the long width upper lids 1j, 1 are placed.
The contact surface of m is marked with adhesive tape (not shown), and two appropriate places are tied with binding bands (not shown) to complete the packing. As described above, the long bottom plates 1f, 1
Of the contact points between h and the short bottom plates 1e and 1g, the two contacting points in the diagonal direction are not bonded,
Depending on the weight of the product and the handling of the paper container 1 when the product is stored, the bottom of the box may be weak against the weight, or the short width bottom plates 1e and 1g may be peeled off from the unbonded portion. However, as described above, such a problem does not actually occur because it is bound by the binding band through the bottom plates 1e and 1g. Since the paper container 1 which is no longer needed after the product is taken out can be folded and easily returned to a flat shape, the waste cardboard can be stored and transported in a small space.

In the embodiment shown in the accompanying drawings, the shape of the paper container 1 surrounded by the four side plates has a rectangular shape in plan view, but it is not particularly limited to a rectangular shape in plan view. The present invention can of course be applied to a square shape in plan view. The positions where the bent portions P5 and P5 are formed and the sizes of the bent portions P5 and P5 are not limited to those shown in the accompanying drawings, and for example, curved small bent portions. The one with P5 and P5 formed is also
Of course, the present invention can be applied. As described above, the present invention is completed by forming the bent portions P5 and P5 by pressing the open side end sides of the facing two bottom plates 1e, 1g (1f, 1h), and the pressing processing is also performed on the other bent portions P1. ~ P5, P6, P
It can be easily performed at the same time as the pressing process of 7.

[0051]

According to the paper container and the method of manufacturing the same of the present invention described above, the following effects can be obtained. That is, a paper container formed by assembling short and long bottom plates is once folded at the paper container factory and delivered to the boxing factory.When the box is packed at the boxing factory, the folded paper container is taken out from both ends Just apply force in the direction,
Since it is possible to instantly restore the original assembled shape, the troublesome and time-consuming work that has conventionally been done by assembling paper containers at the packaging factory side and fixing the bottom plate with adhesive tape or staples is unnecessary. You can Therefore, the time, personnel, and space for that can be reduced.

In particular, of the bottom plates that face each other diagonally and face each other vertically after the paper container is assembled, the bottom plate having the curved bent portions is formed at the end of each bottom plate. At the time of folding and assembling the paper container, the end of the bottom plate can move along the outer surface of the upper bottom plate, so that the folding and assembling can be smoothly performed, and the bent portion is formed in a curved shape. Therefore, when the force applied to the bent portion disappears, the open side end of the folded paper container is immediately restored to the original flat shape, and there is an advantage that it does not hinder the handling of the paper container.

On the other hand, in the case where the bent portion is formed near the tip of the open side end of the bottom plate, the tip portion bent downward even after the assembling of the paper container is small. Therefore, it does not hinder the handling of paper containers.

Further, since the paper container can be stored in a folded state until just before the cartoning work, a large number of cartoners can be stored even if the storage space is small. It is possible to prevent breakage, and by folding and bundling in a fixed quantity, it is convenient to take out the required number of paper containers immediately.

[Brief description of drawings]

FIG. 1 is a bottom perspective view of a paper container according to a first embodiment of the present invention in a state in which the paper container is bent to some extent.

FIG. 2 is a front view of a corrugated cardboard sheet forming a paper container.

FIG. 3 is a perspective view from the bottom side showing the method for assembling the paper container.

FIG. 4 is a perspective view from the bottom side showing the state after assembling the paper container.

FIG. 5 is a partially cutaway perspective view of a paper container.

FIG. 6 is a partially cutaway perspective view showing a folding and restoring method of the paper container.

FIG. 7 is a partially cutaway perspective view of a paper container.

FIG. 8 is a perspective view showing a state after folding the paper container.

FIG. 9 is a bottom perspective view of the paper container according to the second embodiment of the present invention in a state in which the paper container is bent to some extent.

FIG. 10 is a front view of a corrugated cardboard sheet forming a paper container.

FIG. 11 is a perspective view from the bottom side showing the method for assembling the paper container.

FIG. 12 is a bottom perspective view showing a state after assembling the paper container.

FIG. 13 is a partially cutaway perspective view of a paper container.

FIG. 14 is a partially cutaway perspective view showing a folding and restoring method of a paper container.

FIG. 15 is a partially cutaway perspective view of a paper container.

FIG. 16 is a perspective view showing a state after folding the paper container.

FIG. 17 is a bottom perspective view of the paper container according to the third embodiment of the present invention in a state in which the paper container is bent to some extent.

FIG. 18 is a bottom perspective view showing a state after assembling the paper container.

FIG. 19 is a perspective view showing a state before assembling a paper container according to a conventional technique.

FIG. 20 is a partially cutaway perspective view showing a state after assembling the paper container.

[Explanation of symbols]

 1 Paper containers 1a, 1b, 1c, 1d Side plates 1e, 1f, 1g, 1h Bottom plates P1 to P7 Bent parts

Claims (5)

[Claims] 1. A paper container provided with four bottom plates formed by being bent inward from a lower end of the side plates, wherein a shape surrounded by four side plates has a quadrilateral shape in a plan view.
Of the two bottom plates, the two bottom plates to be located on the inner side are in contact with the inner surfaces of the two bottom plates to be located on the outer side,
Of the four contact surfaces, the contact surfaces of the two bottom plates located in one of the diagonal directions of the quadrangular shape are adhered, and a bent portion is diagonally formed with the base end of the adhered part of the bottom plate as one end. Of the two bottom plates to be positioned on the outer side, a curved bent portion for directing the open side end of the bottom plate to the outside is provided at a position from a side edge of a portion which is not adhered and which is in contact with the bottom edge to a tip side. A paper container characterized by being formed respectively. 2. A method for manufacturing a paper container, wherein a shape surrounded by four side plates is a quadrangular shape in a plan view, and the bottom plate is formed by being bent inward from a lower end of the side plate. Of the four bottom plates, the two bottom plates to be located on the inner side are in contact with the inner surfaces of the two bottom plates to be located on the outer side. The bottom surface of the bottom plate is adhered, and a bent portion is formed on a diagonal line whose one end is the base end of the adhered part of the bottom plate. A method for manufacturing a paper container, comprising forming curved bent portions, each of which has an open side end of the bottom plate facing outward, from a side to a tip side. 3. A paper container provided with four bottom plates formed by being bent inward from a lower end of the side plates, wherein a shape surrounded by four side plates has a quadrilateral shape in plan view.
Two bottom plates facing each other on one side of the bottom plates are in contact with inner surfaces of two bottom plates facing each other on the other side,
Of the four contact surfaces, the contact surfaces of the two bottom plates located in one of the diagonal directions of the quadrangular shape are adhered to each other, and from the middle of the side of the adhered part of the bottom plate to the middle of the tip side. A paper container, characterized in that each of the bottom plates is formed with a bent portion with its open end facing outward. 4. A method for manufacturing a paper container, wherein a shape surrounded by four side plates is a quadrangular shape in a plan view, and four bottom plates are formed by bending inward from a lower end of the side plates. Two bottom plates facing each other on one side of the bottom plates are in contact with the inner surfaces of the two bottom plates facing each other on the other side. A paper container characterized in that the contact surface portion is adhered, and a bent portion for directing the open side end of the bottom plate to the outside is formed at a position from the middle of the side edge of the bottom plate to the middle of the leading edge. Manufacturing method. 5. The bottom plate is folded by applying a force inward from each of the diagonal directions to which the bottom plate is not adhered, and after the folding, the bottom plate is adhered to each of the diagonal directions from the original direction by applying a force. The method for manufacturing a paper container according to claim 2, wherein the shape is restored.