JP7505156B2 - Paper containers - Google Patents

Description

The present invention relates to a paper container assembled from blank sheets, for example for packaging food, etc.

Conventionally, tray-shaped containers that are assembled from blank paper sheets and have a flange at the top end have been known.

For example, the following Patent Document 1 describes an assembled paper container that includes a tray-shaped container body assembled from blank sheets whose main material is paper and a resin film coated on the inner surface of the container body, in which the container body is provided with a bottom surface, multiple side surfaces rising from the bottom surface, and an upper end flange that is connected to the multiple side surfaces and has a flush top surface after assembly.

JP 2019-172339 A

Incidentally, in paper containers assembled from blank sheets such as those described above, letters, figures, etc. may be printed on the blank sheets. In addition, after the contents such as food are placed in the paper container, the flange is sealed with a resin film. When the consumer peels off the resin film, a tab may be provided at the corner of the flange to make it easier to peel off, and the position of the tab may be determined in a specific direction relative to the orientation of the printed letters or figures (for example, if letters indicating the start point of peeling, such as "Please peel from here," are printed on the flange, the tab will also be determined in that position).

In the manufacturing process of paper containers as described above, blank sheets produced on a blanking line are stacked in multiple layers to form a stack, and this stack is then brought into the start of a series of processing lines consisting of a box-making machine (case former) that assembles the containers and a thermocompression machine that coats the resin film. The blank sheets are then picked up one by one from the top of the stack by a destack feeder and fed into the processing line.

However, in the conventional technology described in Patent Document 1, when stacking the blank sheets, the worker may mistakenly stack the blank sheets in a direction different from the specified direction (e.g., a direction shifted by 180 degrees).

In view of the above circumstances, the object of the present invention is to provide a paper container that can prevent workers from stacking pre-assembled blank sheets in the wrong direction.

In order to achieve the above object, a paper container according to one embodiment of the present invention is a paper container assembled from a paper blank sheet, and has a bottom surface portion, side surfaces portion, and flange portions. The bottom surface portion is formed in an octagonal shape having a pair of long sides, a pair of short sides, and two pairs of corner sides in a plan view. The side surfaces portion comprises a pair of long side surfaces rising from the pair of long sides, a pair of short side surfaces rising from the pair of short sides, and two pairs of corner side surfaces rising from the two pairs of corner sides. The flange portions comprise a pair of long flange portions connected to the pair of long side surfaces, a pair of short flange portions connected to the pair of short side surfaces, and two pairs of corner flange portions connected to the two pairs of corner side surfaces, and form the upper surface of the paper container. At least one of the corner flange portions has a marker portion having a shape different from the other corner flange portions.

With this configuration, by having a marker on the corner flange, workers can stack multiple blank sheets before assembly so that the marker is always in the same position, preventing the blank sheets from being stacked in the wrong direction.

The marker portion may be a concave notch.

This allows the marker portion to be engaged with, for example, a rod-shaped guide member to guide the blank sheets when stacking them, improving work efficiency and allowing the stack of blank sheets to be held stably.

The marker portion may be a plurality of concave notches formed in a wave shape.

The marker portion may be a convex portion that protrudes outward on the same plane as the upper surface.

The marker portion may be formed on two adjacent corner flange portions via the long flange portion or the short flange portion.

By providing the markers on two adjacent corner flanges, the design is improved, and if tabs are provided on the two corner flanges to accommodate both right-handed and left-handed people, the positions of the tabs can be aligned with the positions of the markers.

The marker portion may be formed in an area of the corner flange portion that does not overlap the long flange portion or the short flange portion with other flange portions during assembly.

This allows the area that remains blank and does not overlap during assembly to be effectively used for the marker section, and also minimizes the amount of cutting required to form the marker section on the blank sheet.

As described above, the present invention can prevent workers from stacking blank sheets before assembly in the wrong direction. However, this effect does not limit the present invention.

FIG. 1 is a planar perspective view showing the appearance of a paper container according to a first embodiment of the present invention. FIG. 2 is a bottom perspective view of the paper container of FIG. 1. FIG. 2 is a front view of the paper container of FIG. 1. FIG. 2 is a left side view of the paper container of FIG. 1. FIG. 2 is a plan view of the paper container of FIG. 1. FIG. 2 is a bottom view of the paper container of FIG. 1. FIG. 2 is a development view showing a blank sheet for the paper container. FIG. 4 is a plan view showing the appearance of a paper container according to a second embodiment of the present invention. FIG. 11 is a plan view showing the appearance of a paper container according to a third embodiment of the present invention.

The following describes an embodiment of the present invention with reference to the drawings.

First Embodiment
First, a first embodiment of the present invention will be described.

[Overview of paper containers]
Fig. 1 is a top perspective view showing the appearance of a paper container in one embodiment of the present invention. Fig. 2 is a bottom perspective view of the paper container of Fig. 1. Fig. 3 is a front view of the paper container, Fig. 4 is a side view of the paper container, Fig. 5 is a plan view of the paper container, and Fig. 6 is a bottom view of the paper container. Fig. 7 is a development view showing a blank sheet before assembly of the paper container.

As shown in each figure, the paper container 100 according to this embodiment is a container that is folded from a single blank sheet 50 made of paper (e.g., cardboard) using a box-making machine (case former) or the like, and assembled into a tray shape with an open rectangular top when viewed from above. Of course, the shape of the paper container 100 is not limited to a rectangle, and it may be any other polygonal shape as long as it has a bottom surface, sides rising from the bottom surface, and a tray shape with an open top.

As shown in each figure, this paper container 100 has a bottom portion 1, multiple side portions 2 (2a, 2b, 2c) rising from the bottom portion 1, and a rectangular frame-shaped flange portion 3 that is connected to the multiple side portions 2 and is located at the upper end of the entire container.

The bottom surface portion 1 is formed in an octagonal shape having a pair of long sides, a pair of short sides, and two pairs of corner sides in a plan view. In the blank sheet 50, a first fold 4a, a pair of folds 4b, and two pairs of folds 4c are formed in a perforated pattern, for example, by a sewing machine blade, corresponding to the pair of long sides, a pair of short sides, and two pairs of corner sides. The folds 4 form the side surface portion 2, which is a pair of long side portions 2a rising from the pair of long sides of the bottom surface portion 1, a pair of short side portions 2b rising from the pair of short sides, and two pairs of corner side portions 2c rising from the two pairs of corner pieces.

As shown in Figures 1 to 4, each side portion 2 projects outward from the outer end of the bottom portion 1 and forms a tapered surface (inclined surface) that is inclined relative to the bottom portion 1. However, the side portion 2 may be formed at a right angle to the bottom portion 1.

The flange portion 3 has a pair of long flange portions 3a corresponding to the pair of long side portions 2a, a pair of short flange portions 3b corresponding to the pair of short side portions 2b, and two pairs of corner flange portions 3c corresponding to the two pairs of corner side portions 2c.

As shown in Figures 1, 2, 5, 6, and 7, each flange portion 3 is formed to protrude outwardly and substantially horizontally from the upper end of each side portion 2 by each fold 5 (5a corresponding to long side portion 2a, 5b corresponding to short side portion 2b, and 5c corresponding to corner side portion 2c) of the blank sheet 50.

Of these, the long flange portion 3a and the short side portion 3b are formed in a rectangular shape, and the corner flange portion 3c is formed in an arc-shaped semi-cylindrical shape on its outer side.

2, 6 and 7, the long flange portion 3a and the short flange portion 3b have cantilever-shaped corner connection pieces 31 at both ends in the longitudinal direction (X direction and Y direction) of the long flange portion 3a and the short flange portion 3b, which protrude from the both ends and connect to the corner flange portions 3c. Specifically, a pair of corner connection pieces 31 protruding from adjacent ends of the adjacent long flange portion 3a and the short flange portion 3b are adhered to the back surface of each corner flange portion 3c, thereby connecting the long flange portion 3a and the short flange portion 3b to the corner flange portion 3c.

As shown in Figures 2 to 4 and 6, a total of eight stacking ribs 22 are provided on both upper ends of the long side portion 2a and the short side portion 2b to form a predetermined gap between the paper containers 100 when stacking multiple paper containers 100, making them easier to grasp.

As shown in Figures 2, 6 and 7, the outer end of the corner flange 3c (the end opposite the corner side 2c) has an R shape with a predetermined radius of curvature. On the other hand, the outer end of the corner connection piece 31 (the end opposite the long side 2a and short side 2b) also has an R shape with the same or approximately the same radius of curvature as the corner flange 3c.

By matching the R-shape of the corner connection piece 31 with the R-shape of the corner flange portion 3c, even if some misalignment occurs when the corner connection piece 31 is adhered to the corner flange portion 3c, the misalignment can be made less noticeable.

Although not shown, after assembly, the inner surface of the paper container 100 is covered with a resin film. The resin film is a single-layer or multi-layer film of approximately 50 to 500 μm thickness made of a thermoplastic resin that can be welded to the inner surface of the paper container 100, and has the function of preventing contents such as food, including liquids and other fluids, from leaking out to the outside.

Examples of thermoplastic resins include polyethylene (PE), polypropylene (PP), polyvinyl chloride, polyethylene terephthalate (PET), ethylene-vinyl acetate copolymer (EVA), etc. Considering that the paper container 100 will be separated and disposed of after use, a film with easy peel properties is preferable. This resin film is suction-pressurized to cover the paper container 100 at a predetermined temperature, for example by forming a vacuum-pressurized air.

[Blank sheet]
Next, the blank sheet 50 will be described with reference to FIG.

As shown in FIG. 7, in the center of the blank sheet 50 is the aforementioned octagonal bottom surface portion 1, which will become the bottom surface of the paper container 100 after assembly. From the bottom surface portion 1, the above-mentioned inverted trapezoid long side surface portion 2a is formed on the outside of the long side fold 4a, the inverted trapezoid short side surface portion 2b is formed on the outside of the short side fold 4b, and the rectangular corner side surface portion 2c is formed on the outside of the oblique side fold 4c.

Furthermore, the long flange portion 3a is formed from the long side portion 2a to the outside of the fold 5a, the short flange portion 3b is formed from the short side portion 2b to the outside of the fold 5b, and the corner flange portion 3c is formed from the corner side portion 2c to the outside of the fold 5c.

The above-mentioned corner connection pieces 31 are formed at both ends of the long flange portion 3a and the short flange portion 3b, across the boundaries with each corner flange portion 3c.

Here, in the blank sheet 50, the triangular portion 21 surrounded by the corner side portion 2c, the corner connection piece 31, and the long side portion 2a or the short side portion 2b (including the stacking rib 22) is cut along the shape of the corner connection piece 31 and the long side portion 2a or the short side portion 2b while being connected to each of the corner side portions 2c. Then, as shown in FIG. 1 and FIG. 5, during assembly, the portion 21 is positioned so as to overlap both side ends of the long side portion 2a or the short side portion 2b, and functions as a side reinforcing portion 21. The portion 21 may be adhered to both side ends of the long side portion 2a or the short side portion 2b with glue or the like. The portion 21 may also be fixed to both side portions by being integrally covered with the resin film while overlapping both side ends of the long side portion 2a or the short side portion 2b.

[Marker for preventing reverse stacking]
Next, the marker portion provided on the corner flange portion 3c will be described.

As shown in each figure, two of the corner flange portions 3c (e.g., the two corner flange portions 3c at the upper left and lower left in a plan view) that are adjacent to each other via the long flange portion 3a or short flange portion 3b are provided with a marker portion 7 having a different shape from the other corner flange portions 3c. In this embodiment, the marker portion 7 is a concave (e.g., semicircular) notch.

The marker section 7 is provided to prevent workers from stacking multiple blank sheets 50 in the wrong direction (a direction 180 degrees different) when assembling the paper container 100.

That is, in the paper container 100 according to this embodiment, letters, figures, etc. may be printed on the blank sheet 50. After the assembled paper container 100 is filled with food or other contents, the flange portion 3 is sealed with a resin film. When the consumer peels off the resin film, a tab may be provided at the corner of the film corresponding to one of the corner flange portions 3c to make peeling easier, and the position of the tab may be determined in a predetermined direction relative to the orientation of the printed letters or figures (for example, if letters indicating the start point of peeling, such as "Please peel from here," are printed on one of the corner flange portions 3c, the tab will also be determined in that position).

In the manufacturing process of the paper container 100, the blank sheets 50 manufactured on the blanking line are stacked in multiple layers to form a stack, and this stack is then transported to the start of a series of processing lines consisting of a box-making machine (case former) that assembles the paper container 100 and a thermocompression machine that coats the resin film. The blank sheets 50 are then picked up one by one from the top of the stack by a destack feeder and fed into the processing line.

In this case, the orientation of the blank sheets 50 stacked initially will not change until the end of the processing line, so the blank sheets 50 must be set in the correct orientation when they are stacked. However, when workers stack the blank sheets 50, they may mistakenly stack them in a direction that is 180 degrees different from the direction specified for the printing direction.

Therefore, in this embodiment, marker portions 7 are formed on the two corner flange portions 3c, and the worker stacks multiple blank sheets before assembly so that the marker portions 7 are always in the same position, thereby preventing the blank sheets from being stacked in the wrong direction.

As shown in FIG. 6, the marker portion 7 is formed in an area of the corner flange portion 3c that does not overlap with the long flange portion 3a or the short flange portion 3b during assembly.

This allows the area that does not overlap during assembly to be effectively used for the marker section 7, and also minimizes the cutting process required to form the marker section 7 on the blank sheet 50.

Furthermore, if a similar marker portion 7 were formed on the long flange portion 3a or the short flange portion 3b, the marker portion 7 would occupy about half the width of the long flange portion 3a or the short flange portion 3b, which could reduce the sealing strength of the resin film. However, if the corner flange portion 3c has a width up to twice as large as the long flange portion 3a or the short flange portion 3b, the formation of the marker portion 7 can prevent a reduction in sealing strength.

In addition, in this embodiment, by forming the marker portion 7 as a concave notch, when stacking multiple blank sheets 50, the marker portion 7 can be engaged with, for example, a rod-shaped guide member to guide it, improving work efficiency and allowing the stack of blank sheets 50 to be stably held.

In addition, in this embodiment, by providing marker portions 7 on two adjacent corner flange portions 3c (upper left and lower left in plan view), the design is improved, and if tabs are provided on the two corner flange portions 3c to make it easier for both right-handed and left-handed people to peel off the resin film, the positions of the tabs can correspond to the positions of the marker portions 7.

Second Embodiment
Next, a second embodiment of the present invention will be described. In this and subsequent embodiments, parts having the same functions as those in the first embodiment are denoted by the same reference numerals.

Figure 8 is a plan view showing the appearance of the paper container 100 according to this embodiment. As shown in the figure, the marker portion 7 in this embodiment is formed as multiple (e.g., three) concave cutouts formed in a wave shape.

With this configuration, the same effect as in the first embodiment can be obtained. In this embodiment, when engaging the marker portion 7 with the guide member when stacking the blank sheets 50, the guide member can be configured to match any one of the three recesses.

Third Embodiment
Next, a third embodiment of the present invention will be described.

Figure 9 is a plan view showing the appearance of the paper container 100 according to this embodiment. As shown in the figure, the marker portion 7 in this embodiment is formed as, for example, a semicircular convex portion that protrudes outward on the same plane as the upper surface of the flange portion 3.

Even with this configuration, the same effects as those of the first and second embodiments can be obtained. In this embodiment, when engaging the marker portion 7 with the guide member when stacking the blank sheets 50, the guide member can be configured to be concave to match the convex shape of the marker portion 7.

[Modification]
The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and scope of the present technology.

The shape of the marker portion 7 is not limited to those shown in the above embodiments, so long as it has a shape different from the corner flange portion 3c other than the corner flange portion 3c on which it is provided. For example, the marker portion 7 may be formed as a V-shaped or rectangular notch, or as a V-shaped or rectangular protrusion.

In each of the above-described embodiments, the marker portion 7 is provided on two adjacent corner flange portions 3c (upper left and lower left in plan view) among the four corner flange portions 3c. However, the adjacent locations may be the upper left and upper right, or the lower left and lower right in plan view.

Furthermore, the marker portion 7 may be provided on only one of the four corner flange portions 3c, or on any three of them.

The shape of the paper container 100 is not limited to those shown in the above-mentioned embodiments, but can be changed as appropriate, and the shape and size of the marker portion 7 can also be changed accordingly.

Reference Signs List 1: bottom surface portion 2a: long side surface portion 2b: short side surface portion 2c: corner side surface portion 3a: long flange portion 3b: short flange portion 3c: corner flange portion 4a, 4b, 4c: folds 5a, 5b, 5c: folds 7: marker portion 21: side surface reinforcement portion 22: stacking rib 31: corner connection piece 50: blank sheet 100: paper container

Claims (6)

A paper container assembled from a paper blank sheet,
A bottom surface portion formed in an octagonal shape having a pair of long sides, a pair of short sides, and two pairs of corner sides in a plan view;
a side portion including a pair of long side portions rising from the pair of long sides, a pair of short side portions rising from the pair of short sides, and two pairs of corner side portions rising from the two pairs of corner sides;
A flange portion that forms the upper surface of the paper container includes a pair of long flange portions that are connected to the pair of long side portions, a pair of short flange portions that are connected to the pair of short side portions, and two pairs of corner flange portions that are connected to the two pairs of corner side portions.
At least one of the corner flange portions has a marker portion having a shape different from the other corner flange portions. The paper container according to claim 1,
The marker portion is a concave cutout. The paper container according to claim 2,
The marker portion is a plurality of concave cutouts formed in a corrugated shape. The paper container according to claim 1,
The marker portion is a convex portion that protrudes outward on the same plane as the upper surface of the paper container. The paper container according to any one of claims 1 to 4,
The paper container, wherein the marker portions are formed on two of the corner flange portions adjacent to each other with the long flange portion or the short flange portion interposed therebetween. The paper container according to any one of claims 1 to 5,
The paper container, wherein the marker portion is formed in an area of the corner flange portion that does not overlap the long flange portion or the short flange portion with another flange portion during assembly.

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