JPS6126171Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a paper container formed by folding a single unfolded blank for storing milk, juice, etc.

Generally, paper containers for storing milk, juice, etc. are formed by inserting ruled lines, which are folding lines, from the front side of an unfolded carton blank, and folding the blank along the ruled lines.

That is, as shown in FIG. 1, the front side 1a of the blank 1 is recessed into the back side 1b to form a regular ruled line 2, and as shown in FIG. 2, the blank is bent toward the back side to form a container. was. In such bending, delamination 2a occurs inside the folded portion where the ruled lines are provided, thereby making the paper more likely to bend.

However, in recent years there has been a strong demand for thinner paper for the purpose of resource conservation, and there is a tendency for thinner paper to be used for milk containers and the like. In this case, especially when the top is bent from the horizontal line that separates the body and top (lid) of the container, that part does not bend sharply, which not only spoils the aesthetics, but also sometimes There was a problem with the seal failing and the contents leaking out.

In view of this, the present invention aims to provide a paper container in which the top or bottom part of even thin paper is folded sharply from the body, which is not only aesthetically pleasing but also prevents sealing defects. do.

Examples of the present invention will be described below.

Generally, the thinner the paper, the lower the paper stiffness, and the stiffness approaches the ruled line torque value, which is the bending resistance of the ruled line, and in some cases, the paper stiffness may become smaller than the ruled line torque value. In this case, the paper becomes curved as a whole and does not bend along the ruled lines as shown in FIG.

Further, the stiffness of paper is generally weaker in the horizontal direction than in the vertical direction, and therefore it is necessary to particularly reduce the torque value for ruled lines in the horizontal direction. Furthermore, the lower the torque value at the beginning of folding, the better the top formability of Gebert top, slant top, or flat top type carton blanks.
Experiments have shown that there is no problem even if the torque value at 90 degrees is slightly higher.

Therefore, as shown in FIG. 4, the present inventor formed a reverse ruled line 3 so that the back side 1b of the carton blank 1 was depressed and protruded to the front side 1a, and the blank was moved along the reverse ruled line 3. I thought about folding it to the back side to form the top part.

Comparing the torque value when forming the regular ruled line 2 on the front side of the blank 1 and the torque value when forming the reverse ruled line 3 on the back side, the results are as shown in Figure 6, and the torque value for the reverse ruled line 3 gradually increases as the bending angle increases, as shown in the solid line graph a, while the torque value for the regular ruled line 2 is the initial torque (up to a bending angle of about 40 degrees), as shown in the chain line graph b.
rises rapidly and then becomes almost constant. In this way, in the case of normal ruled line 2, the initial torque is
However, since the initial torque of the reverse ruled line 3 is small, the blank can be bent sharply.

In ordinary carton blanks, etc., bending of 90 degrees or more is common, and reverse creases where the torque value at 90 degrees is higher than regular creases have not been seen in the past, but various experiments have shown that bending angles of 40 to 50 degrees It has been found that the reverse ruled line, which has a lower initial torque, is more advantageous for folding thin sheets.

Next, an example of a container actually provided with reverse ruled lines will be described.

7 to 9, the unfolded blank 10 has a body 11 of a container 30 to be bent and formed,
It consists of a top part 12 that closes off the upper part of the body part 11 and a bottom part 13 that closes off the lower part of the body part 11. Regular ruled lines 14, 15, and 16 are formed vertically to form the four sides of the rectangular cylindrical container 30, and the bottom part 13 and body part 11 are formed with continuous regular ruled lines 17a, 17b, 17c, and 17d. It is sectioned.

At the boundary between the top portion 12 and the body portion 11,
Regular ruled lines 18 and 19 are formed on a pair of side edges that are opposite to each other when the container is bent and formed, and reverse ruled lines 20 and 21 are formed on the other pair of side edges. An adhesive margin 22 is provided at the left end of the developed blank 10, and this adhesive margin 22 is pasted inside the right end of the blank.

The bottom flaps 23 and 24, which are bent by the regular ruled lines 17a and 17c, are provided with regular ruled lines 2 in a chevron shape.
5, 26 are provided, and a gluing margin 28 is formed at the tip of the bottom flap 27 corresponding to the regular ruled line 17b, and this gluing margin 28 is provided on the bottom flap 23,
24 is folded inward to form the bottom portion, it is attached onto the tip of the bottom flap 29 corresponding to the regular ruled line 17d.

Top flaps 31 and 32 corresponding to the reverse ruled lines 20 and 21 are provided with chevron-shaped regular ruled lines 33 and 34, and top flaps 35 and 36 adjacent to these top flaps 31 and 32 are provided with oblique regular ruled lines that are continuous with the regular ruled line 33. 37 and 38 are formed.
Further, the top flaps 31, 32, 35, 3
The upper edge of 6 has an adhesive margin of 39, 40, 4, respectively.
1 and 42 are provided.

The top portion of the container 30 is formed by folding the triangular portions surrounded by the ruled lines of the opposing top flaps 31 and 32 inward as shown in FIG. At the same time, the top flaps 35 and 36 are formed into a roof shape, and the adhesive margins 41 and 42 at the tips thereof are attached to each other to form a knob portion. That is, the triangular part of the container with the top open is pressed by a guide bar to first fold that part inward, and then the side top flaps 35 and 36 are folded by another guide bar. do.

When dispensing the liquid in the container, push open the end of the knob as shown in FIG.
The right end portions of the top flaps 35 and 36 are bent outward along the line 38, and then the center of the upper end of the top flap 31 (the apex of the triangular portion) is pulled out to form the spout 43.

In this embodiment, reverse ruled lines are formed only at the lower ends of the pair of opposing top flaps 31 and 32, but this is to facilitate subsequent folding since the triangular portions are first largely folded inward. . Note that the reverse ruled line may be formed not only at the boundary between the pair of top flaps but also at the boundary between the bottom flap and the trunk.

In other words, if reverse ruled lines are appropriately formed on the inside (back side) of the container, the bending will be sharp, the adhesive margins will be completely adhered to each other, and the liquid will be completely sealed.

Furthermore, the formation of ruled lines is performed by a punching method, and is performed in two steps: the first punching is a reverse ruled line, and the second punching is a regular ruled line, but the regular ruled line and the reverse ruled line may be formed at the same time. .

The present invention is particularly effective when the paper thickness is thin, and it is clear that even when the paper thickness is thick and the paper stiffness is high, reverse ruled is advantageous compared to regular ruled because the initial torque value is small.

As explained above, the present invention involves adding ruled lines to a sheet of unfolded paper to form the body of the container and the top and bottom parts that close the top and bottom of this body, and then inserting the paper along the ruled lines. In folded paper containers, at least the horizontal ruled line that separates the body and the top part is inserted from the back side of the paper on two opposite sides, so the paper can be folded sharply and easily. The sealing condition of the bottom part is perfect and aesthetically pleasing, and the effect is particularly effective for folding thin paper.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the conventional regular line forming state, Fig. 2 is an explanatory diagram of the folding state of regular lined paper, Fig. 3 is an explanatory diagram of the conventional folding state of thin paper, and Fig. 4 is the reverse of the present invention. Figure 5 is an explanatory diagram of the folding state of reverse ruled paper, Figure 6 is a torque value comparison graph between regular ruled lines and reverse ruled lines,
Figure 7 is a developed view of a container with reverse ruled lines according to the present invention.
FIG. 8 is a perspective view of the top of the container in an assembled state, and FIG. 9 is a perspective view of the top of the container in a state in which a spout is formed. 1, 10... Blank, 11... Torso, 12...
...Top part, 13...Bottom part, 18, 19...
Normal ruled line, 20, 21... Reverse ruled line, 23, 24, 2
7, 29...Bottom flap, 31, 32, 3
5,36...Top flap.

Claims (1)

[Scope of utility model registration request] A paper container in which a sheet of unfolded paper is lined to form a body of the container, a top portion and a bottom portion that close the top and bottom of the body, and the paper is folded along the ruled lines, at least A paper container characterized in that at least a part of the horizontal ruled line demarcating the body and the top part is reverse ruled by inserting a ruled line from the back side of the paper over the entire length between the vertical ruled lines delimiting the side surface of the container.