JP4499253B2 - Method for forming stack line of paper container and paper container with stack line - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a stack line forming method for paper containers, and particularly to a stack line forming method for deep drawn paper containers suitable for automatically filling food containers and the like with a filling machine, and a deep drawn paper container manufactured by the method. It is.
[0002]
[Prior art]
Deep-drawn paper containers that are molded and manufactured by pressing a piece of paperboard are low in calories burned during disposal and do not damage the furnace, so they are widely used as packs for foodstuffs instead of plastic containers. It is coming. For example, as shown in FIG. 6, the container is a square container having a deep drawn shape and an outer peripheral edge wound around, and this is a curved sheet by pressing a sheet of paper base paper with the corners rounded down while being heated. A plurality of fold wrinkles extending radially are formed at the corners to be squeezed, the flange part, the side wall part, and the bottom part are formed first, and the outer periphery of the flange part is further processed and pressed in the next step. Thus, the edge winding form is obtained. When such a deep drawn paper container is automatically filled with the contents by a filling machine, a plurality of stacked containers (stacked) are set in the machine as one unit (basic unit) A configuration is adopted in which the containers are separated and taken out one by one and transferred to a filling section to quantitatively fill the container with the contents. However, this type of deep-drawn paper container has a tapered side wall so that when it is stacked, it is in close contact with each other as shown in FIG. 7A or as shown in FIG. 7B. It becomes the form which the side wall outer surface of the upper container contacted. In the former case, the side walls are exactly overlapped, so when separating and taking out, there is a bite between the lower container and the container due to negative pressure and pressurization, making separation difficult, and stable supply due to machine operation or high-speed automatic supply There was a problem that was difficult. In the latter case, the overlapping state such as the position and orientation is not uniform and unstable, and it is difficult to achieve stable supply or automatic automatic supply at high speed. In addition, since the height of one unit in a stacked state varies, not only the appearance is cluttered, but also a cardboard box for packing a predetermined amount is larger than the set value. There was a problem that had to be prepared. Further, if there is a gap in the packaged state, it may move during transportation and be easily affected by impact, resulting in a deformation, which deteriorates the product yield.
[0003]
[Problems to be solved by the invention]
The object of the present invention is to solve these problems, that is, when the containers are stacked, the overlapping state does not adhere to each other and is constant and stable, and the vertical dimension (stack height) when the predetermined number is stacked is constant. At the same time, it is an object of the present invention to provide a method of processing a paper container so that stable supply in a filling machine or high-speed automatic supply is possible, and such a container.
[0004]
[Means for Solving the Problems]
The method of the present invention is a method for manufacturing a paper container comprising a bottom part, a side wall part, and a flange part in which a curved part is formed by a plurality of fold wrinkles extending radially, and is provided on a surface having the same shape as the side wall surface of the container. Using a female member having a concave groove portion and a male member having a convex portion in a fitting relationship with the concave groove portion, the surface of the female member and the side wall peripheral surface of the container are in close contact with each other The male member is pressed so that the convex portion of the male member fits into the concave groove of the female member, and a flange is formed only on the folded wrinkle portion of the container. A stack line was formed at a predetermined parallel position.
Further, this method is adopted for a container in which the surface of the flange portion is flat to the tip and the dimension between the edge winding portion and the side wall portion on the back surface is longer than the thickness of the tip of the female member.
Further, when pressing, the moisture, heating temperature, pressing pressure, and pressing time are adjusted according to the conditions such as the paper thickness of the processed portion and the folding wrinkles.
Stack line with paper container of the present invention, the paper container comprising a plurality of folding the bottom curved portion is formed by wrinkles and the side wall portion and a flange portion extending radially, parallel to the flange, the container is superimposed In this case, a convex stack line that engages with the flange portion of the lower container is provided only in the folded wrinkle portion of the side wall at a predetermined distance from the flange portion.
The paper container is a deeply drawn square container, and edge winding is formed on the outer periphery of the flange portion.
A paper container lid body with a stack line according to the present invention is a paper container lid body including a top plate and a side wall portion in which a curved portion is formed by a plurality of fold wrinkles extending radially, and the lid body is parallel to the flange. A convex stack line that engages with the shoulder portion of the lower lid when overlaid is provided only on the folded wrinkle portion of the side wall at a predetermined distance from the top plate.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
There is an advantage that when the containers are stacked, they can be stored compactly if they are in close contact with each other, but when set in an automatic filling device, the containers are close to each other when they are separated and taken out. Therefore, it becomes negative pressure and cannot be handled smoothly. In order to solve this problem, the present invention provides a gap between the containers, and further provides a stack line that engages with the flange portion of the lower container so that the overlapping state is constant and stable. By forming in this way, the stack line of the upper container comes into contact with and engages with the flange portion of the lower container, and the distance between them is constant and stable. In addition, there is a space between the side walls of both containers, and no negative pressure is generated when the upper container is extracted, so that it can be separated and extracted smoothly. When this type of container is manufactured, it is usually packed and stored in a stacked state, transported, and set in an automatic filling machine. At this time, the stacked state is constant and stable. Therefore, a predetermined number is neatly accommodated in the packing container, handling is easy, no waste, and orderly appearance is good.
[0006]
Such a container is manufactured by a process as shown in FIG. That is, a paperboard base as shown in A is used as a raw material and pressed between a male mold and a female mold to form a bottom, a side wall and a flange as shown in B. This press blows hot air, etc. Then, the process is carried out in an appropriate humidity and heating state. At this time, a radial folding wrinkle is formed at a curved portion such as a corner, and deep drawing is performed. Next, as shown in C, the outer peripheral edge of the flange is curled. This is called edge winding, and has a function of preventing the wrinkles of the container from returning and causing a loss of shape as well as a reinforcing function like a rib. As the process, a process of crushing the outer peripheral portion, a process of squeezing and compressing and wrapping, and a series of processes of inserting into the curl groove to form an edge winding are assembled. A, B, and C are the conventional deep drawing paper container manufacturing processes, and the process peculiar to the present invention is the stack line forming process shown in FIG. In the case of a deep-drawn square container, a convex stack line extending in a direction parallel to the flange surface is formed at a position above the side wall of the corner portion, which is positioned above the side wall of the container. The container is sandwiched and pressed between a female member having a concave groove and a male member having a convex portion in a fitting relationship therewith. These corners are wrinkled and paper thick, so blow hot air to meet the proper moisture and temperature conditions, and adjust the press pressure and press time to make a convex stack line. Form.
[0007]
Although the stack line forming process is described as being executed in the final process after the curling process, it may be executed before the curling process and following the deep drawing process. The stack line may be provided over the entire circumference of the side wall, or may be provided in a part such as a corner portion. In the latter case, it is necessary to arrange a plurality of the stack lines in a balanced manner so that the overlapping state is stabilized. Further, the container is not limited to a rectangular container, but can be applied to a circular container and can also be applied to a lid.
[0008]
[Example 1]
FIG. 2A is a plan view showing an example in which the present invention is applied to a square deep-drawn paper container 1 designed as a natto container. In this example, the paperboard base paper is deep-drawn to form the bottom part 11, the side wall part 12 and the flange part 13, and then the conventional manufacturing process in which the outer peripheral edge of the flange part is curled to form the edge winding part 14 is taken. The stack line 15 is formed by pressing the male member 3 against the female member 2 shown in FIG. The male member 3 in which the convex portion 31 having a U-shaped cross section is formed is pressed in a state in which the flange portion 13 of the container 1 is pressed against the distal end portion 21 of the female member 2 and the container 1 is fixed. The female member 2 has a contact surface 20 formed in the same shape as the side wall portion from the tip portion, and a concave groove portion 22 having a U-shaped cross section is formed at a predetermined position. The combination of the female member 2 and the male member 3 is installed at four corner portions of the rectangular container 1 and simultaneously performs a press operation. The driving is performed by a mechanical cam mechanism (not shown), but this may be an air cylinder or a hydraulic drive. As shown in the plan view of FIG. 2A, the container after this process is formed with a stack line 15 having a U-shaped cross section on the side walls 12 of the four corner portions.
FIG. 2 shows a state when this is stacked, in FIG. The stack line 15 of the upper container overlaps with the surface of the flange 13 of the lower container, and in each container, the stack line is positioned with respect to the flange surface, so the distance l between them is constant. The side wall surfaces of the two are not in close contact with each other, and a gap of a predetermined interval is secured between them, so that no negative pressure phenomenon occurs at the time of separating and taking out. Since this relationship is the same among all the containers, the height dimension (stack height) L of the unit in which a predetermined number is stacked in B is also a constant value. When packing, a predetermined amount is packed in the packing container without any gap, and stable and high-speed operation is possible even when set in the filling machine, thereby solving the above-mentioned problems of the prior art.
[0009]
[Example 2]
FIG. 4 shows a different embodiment. The difference from the previous example is the shape of the stack line, and the cross-sectional shape is not U-shaped but L-shaped. The manufacturing process is the same except that the shapes of the female member to be fitted and the concave groove and the convex portion formed in the male member are changed. As shown in the drawing, the flange portion of the lower container is overlapped with the step portion of the upper container. A is an L-shaped stack line processed at a predetermined position on the side wall portion, and B is an L-shaped stack line processed directly from the flange portion 13.
[0010]
[Example 3]
FIG. 5 shows the container lid 5 provided with a stack line 55. The lid 5 covers the container opening surface in such a way that the edge winding portion around the mouth edge of the container is held by the fitting portion 52. One board base paper is pressed to form the top board 51, the fitting part 52, and the side wall part 53. Subsequently, the edge winding part 54 is finally pressed from the outside to form the stack line 55. You may provide in a perimeter of a side wall part, and if it is a square shape, you may provide only in a corner part. The container lid 5 is also stacked as shown in FIG. 5 when it is set in the automatic filling machine or stored / transported. The overlapping state is that the lower surface of the stack line 55 is one lower fitting portion 52 of the lid. It becomes the form which engages with the shoulder part.
[0011]
【The invention's effect】
According to the present invention, in a deep-drawn paper container in which a corner portion is formed by a plurality of fold wrinkles extending radially, a stack line of ridges that engages with a flange portion of a lower container when the containers are stacked. Since the stack line is formed on the deep-drawn paper container by adding a pressing process provided on at least a part of the side wall at a predetermined position from the flange portion, the distance between the upper and lower containers is constant in the stacked state. In the automatic filling machine, a gap of a predetermined dimension is secured, and no negative pressure is generated when separating and taking out, so that the operation is guaranteed to be stable and compatible with high speed. In addition, since the interval between all containers is constant, a predetermined amount is stored in the packing container without any gaps during storage and transportation, which may be handled as a unit, and may be deformed due to impact during transportation. In addition, the yield is not deteriorated and the space is not wasted.
[Brief description of the drawings]
FIG. 1 is a diagram showing a processing form in a manufacturing process according to the present invention.
FIG. 2 is a view showing one embodiment of the present invention, in which A is a plan view of a container and B is a partial cross-sectional view in a stacked state.
FIG. 3 is a view showing a combination example of a female member and a male member used in the present invention.
FIG. 4 is a partial cross-sectional view showing a form in which embodiments in which stack lines having different shapes are formed are stacked.
FIG. 5 shows an example in which the present invention is applied to a container lid.
FIG. 6 is a view showing an example of a conventional paper container.
FIGS. 7A and 7B are diagrams showing a state in which conventional paper containers are stacked, and FIG.
[Explanation of symbols]
1 Paper container 3 Male member
11 Bottom 31 Convex
12 Side wall part 5 Container lid
13 Flange 51 Top plate
14 Edge winding part 52 Fitting part
15 Stack line 53 Side wall part 2 Female member 54 Edge winding part
20 Abutment surface 55 Stack line
21 Tip
22 concave groove

Claims (6)

In a method for manufacturing a paper container comprising a bottom part, a side wall part, and a flange part in which a curved part is formed by a plurality of radially extending wrinkles , a concave groove is formed in the same shape as the side wall surface of the container. And holding the container so that the surface of the female member and the side wall peripheral surface of the container are in close contact with each other. And pressing the male member so that the convex portion of the male member fits into the concave groove of the female member, so that only the folded wrinkle portion of the container is stacked at a predetermined interval position parallel to the flange. How to form a line.   The method for forming a stack line according to claim 1, wherein the flange portion surface is flat to the tip, and the dimension between the edge winding portion and the side wall portion on the back surface is longer than the thickness of the female member tip portion.   3. The stack line according to claim 1, wherein the pressurization and press time are adjusted in accordance with conditions such as paper thickness and folding wrinkles in the processed portion during pressing. Method. In a paper container comprising a bottom part, a side wall part, and a flange part formed by a plurality of fold wrinkles extending radially, the paper container is parallel to the flange and is engaged with the flange part of the lower container when the containers are stacked. A stack line-attached paper container in which convex stack lines to be joined are provided only at the folded wrinkle portion on the side wall at a predetermined distance from the flange portion.   The paper container with a stack line according to claim 4, wherein the paper container is a deep-drawn square container, and an edge winding is formed on an outer periphery of the flange portion. In a paper container lid composed of a top plate and a side wall portion formed by a plurality of fold wrinkles extending radially, a shoulder portion of the lower lid when the lid is overlapped with the flange and parallel to the flange A stack line-attached paper container lid in which convex stack lines to be engaged are provided only at the folded wrinkles on the side wall at a predetermined distance from the top plate.

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