JP2005041199A - Shaping method of paper container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shaping method of a paper container capable for stably shaping the paper container with a uniform shape without breaking at an edge part rolled in the case of an edge rolling process on the outer peripheral part of a dish, a cup or various containers made of paper. <P>SOLUTION: The process is carried out under holding a part corresponding to the outer periphery of the container of a paper board member (1) cut to a blank shape for the container shaping with the upper and lower mold members for flange shaping, under expanding processing a part corresponding to the bottom of the container with the upper and lower molding member, by forming a container shape (3A) opened at one side by connecting a bottom part(B), a circumference of the side wall(W) and a flange part (F) at the outer periphery edge in the horizontal direction, then by pressing and processing it from the outer periphery edge little by little with a flange edge rolling mold member to a circular arc shape. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

Detailed Description of the Invention

  The present invention relates to a method for forming various paper containers, in which a peripheral edge of a vessel such as a dish or cup having a shallow depth for food is pressed into an arcuate edge winding shape while being pressed.

  Plastic containers used for food-plating dishes, lunch boxes for storing food, and other various containers are lightweight and inexpensive, and at the same time, they can be easily molded into complex shaped containers. Is used a lot. On the other hand, disposal of plastic containers that are no longer needed, that is, the incineration problem of burning and processing, has emerged. Incineration is a simple disposal measure, but because the burning calories of plastic, that is, synthetic resin, are extremely high, the incineration temperature is high, the refractory material is burned out, and the service life of the incinerator is significantly shortened. In addition, there is a problem that the repair work is expensive. Furthermore, incineration of plastics has a problem of generating harmful gases and polluting the atmosphere. In order to deal with these problems, in the environmental industry, the efficiency of resource utilization, such as trying to recycle synthetic resin waste products collected separately from trash from daily life or using them for other products The development of resource-recycling technology to be used is recommended. In addition, supermarkets and stores that package foods are changing from creating environment friendly to the earth to paper containers with low combustion calories.

Prior to such changes in the times, technological development relating to the manufacture of paper containers has been actively conducted, and many manufacturing techniques have been introduced in patent gazettes. For example, the specification of Japanese Patent Application No. 8-200542 summarizes the scope of claims, and “a plurality of die forming filaments that extend radially from the peripheral wall portion of the container toward the outer peripheral edge and stop within a predetermined distance are described. A paperboard container provided with a resin layer having liquid impermeability and heat resistance on the entire front surface of the paperboard having a predetermined weight, density and air permeability, and a gas-liquid permeable resin layer on the entire other back surface. A paper container formed by press-molding paperboard, a step of compacting the thickness of the straight outer periphery of the paperboard to be smaller than the curved outer periphery of the curved portion of the paperboard, and the straight outer periphery and the curved outer peripheral portion A method for forming a paper container comprising a step of ironing and compressing with a clearance narrower than the thickness of the sheet, and a step of curling the compressed outer periphery to bend the edge. , Paper with essential requirements Molding apparatus "is disclosed. Japanese Patent Application Laid-Open No. 2001-96646 also relates to a paper container, and similarly summarizes the scope of claims, “two or more ribs connected to the bottom and side walls of the container and parallel to the bottom. A paper container formed by press molding adjacent to each other, and after forming a rib in the center of the container, a method for forming a paper container in which both adjacent ribs adjacent to the rib are simultaneously molded. There is disclosed a “press forming apparatus” in which a concave or convex rib mold member is formed on each mold.
Before these publications were issued, paper containers of various shapes and sizes were formed by forming a sheet of paper into a container shape and curling (edge winding) the outer periphery of the paper into an arc shape. Is already commercially available. Paper containers have the strength required for containers and are soft to the touch due to the edge winding process, and attract many people such as food event venues and sports recreation venues due to their many advantages such as ease of use, ease of use, and low cost. Many are used at the venue.

"Patent Document 1"
Description of Japanese Patent Application No. 8-200542 (paragraph 2 Fig. 1)
"Patent Document 2"
Japanese Patent Laying-Open No. 2001-96646 (second item, FIG. 1)

  With the advancement of paper container molding technology, many types of shapes and sizes of paper containers are available on the market, but the paperboard member of the paper container itself is a relatively thin metal plate such as a steel plate or aluminum plate. Since there is no elasticity and ductility because of different materials, there is a problem in that it must be molded with care because it breaks at that part when subjected to a large tensile bending stress in the opposite direction in the local part of the press molding process. In particular, the outer peripheral edge of the paper container is generally pushed into an annular space groove provided on the outer frame member die, as represented by FIG. 5 and FIG. 6 attached to the specification of Japanese Patent Application No. 8-200542. However, as shown in FIG. 23 and FIG. 24, the curling process is carried out at a stretch into a circular edge winding shape. There is also a thing. In addition, when severe molding is performed depending on the shape and size of the annular space groove portion, a difference between the predetermined shape of the container and the shape of the container that is actually edge-wrapped, that is, a spring back is generated, so the shape is There was a problem of forming into a non-uniform container.

  As a result of various studies on the forming method of various paper containers such as dishes and cups for the purpose of solving such problems, the present invention has a flange which becomes the outer peripheral edge of the side wall peripheral portion when forming from a paperboard member to a container. Paper with a uniform shape without breaking from the edge winding part by forming the edge winding shape while repeating the pressing process in small increments from the outer peripheral edge side of the other side while sandwiching the side wall peripheral surface side of the part It was found that the container can be molded stably. The present invention is configured based on this finding.

Means for solving the problem

  The gist of the present invention is that the portion corresponding to the outer periphery of the paperboard member cut into a container-forming blank shape is sandwiched by the flange-shaped upper and lower mold members, and the portion corresponding to the container bottom is bulged with the container-shaped upper and lower mold members. However, the flange portion is connected horizontally to the bottom surface portion, the side wall peripheral surface portion, and the outer peripheral edge thereof, and formed into a container shape that opens on one side, and then the container-shaped upper and lower mold members are used to form the container-shaped flange portion side wall peripheral surface. While the surface pressure is being applied, a flange edge winding surface having an arc cross-sectional shape is provided on the upper end side surface portion of the container molded lower mold member, and the upper end portion is provided between the container molded lower mold member and the flange molded lower mold member. One or two or more flange edge winding lower mold members that rise and lower in an arc cross-sectional shape, the flange edge winding surface of the container molded lower mold member, and the flange edge winding lower mold member at positions opposite to each other. Container-shaped flange A flange part edge winding upper and lower mold member consisting of a flange-molded upper mold member cut into two or three arc-shaped cross-sectional shapes to be pressed, and repeatedly performs edge winding pressing in a small arc shape from the outer peripheral edge side of the flange part However, it is a method for forming a paper container that is formed into an arcuate edge winding shape.

Hereinafter, the method of the present invention will be described in detail with reference to drawings.
The drawings show an embodiment in which the method of the present invention is carried out by a molding apparatus presented for easy understanding of the method of the present invention. FIG. 1 shows a partial cross-sectional view of a press molding apparatus before molding a paperboard member into a paper container. In FIG. 1, reference numeral 1 denotes a paperboard member cut into a container-forming blank shape. The paperboard member 1 is a corrugated cardboard such as a single-sided cardboard or double-sided cardboard with a corrugated liner (flat surface paper) pasted on one or both sides of a corrugated core paper. Commonly used container paper materials such as composite paper with film are applied. The paper quality is not particularly limited. Further, the shape and size of the paperboard member 1 are not particularly limited, and a blank (original plate) suitable for the shape and size of the paper container to be formed is prepared. 2 is a container forming apparatus. As shown in FIG. 2, the container forming apparatus 2 drives and presses the paperboard member 1 so as to be sandwiched from one side or both sides in the vertical direction, and forms the container shape 3A. From the container-molding upper mold member 4 and the container-molded lower mold member 5 that mold the side wall surface W, and from the flange-molded upper mold member 6 and the flange-molded lower mold member 7 that surround the outside and mold the flange portion F of the container shape 3A. It is configured. That is, as shown in FIG. 1, after installing the paperboard member 1 cut into a container-forming blank shape so as to be sandwiched between the upper and lower mold members of the container-forming device 2, the container outer peripheral equivalent portion of the paperboard member 1 is As shown in FIG. 2, the container-corresponding bottom portion is bulged so as to be pushed into the container-molded lower mold member 5 by the container-molded upper mold member 4 while being lightly clamped by the flange-molded upper mold member 6 and the flange-molded lower mold member 7. Displacement in the direction of the plate surface while processing, forming the container shape 3A into a basic container shape with a flange portion F connected in the horizontal direction to the bottom surface portion B, the side wall peripheral surface portion W, and the outer peripheral edge thereof. To do.
In the bulging process of the present invention, the container outer peripheral portion of the paperboard member 1 sandwiched between the flange-molded upper mold member 6 and the flange-molded lower mold member 7 has a container shape if it is too tightly clamped due to the non-ductile paper quality. The paperboard member 1 flows in accordance with the forming speed of the bulging process due to the problem that the tensile force in the opposite direction acts on the boundary portion between the side wall peripheral surface portion W and the flange portion F of 3A and the paperboard member 1 is torn off. It is necessary to make the holding force easy and light enough to form the flange portion F.

The container portion 3A formed by forming the flange portion F on the outer peripheral edge is gradually formed into an arcuate edge winding shape while repeating edge winding pressing in a small arc shape from the outer peripheral edge side of the flange portion F. 3 and 4 illustrate the edge winding shape forming method in an easy-to-understand manner.
The container shape 3A in which the flange portion F is formed on the outer periphery in FIG. 2 is a bottom surface portion B of the container shape 3A, as shown in FIG. 3 and FIG. In the state in which the side wall peripheral surface W is fixed, the side wall peripheral surface side of the flange portion F is subjected to surface pressure, and the flange-shaped edge winding surface K having a protruding arc cross-sectional shape is formed on the upper end side surface portion of the container forming lower mold member 5 described above. Further, one or two or more flange edge wrapping lower mold members 8 that move up and down with an arc-shaped cross section at the upper end between the container molded lower mold member 5 and the flange molded lower mold member 7 and the container molded Two or three or more arc-shaped cross-sections that press the flange portion F of the container shape 3A to a position facing the flange portion edge winding lower surface member K of the lower mold member 5 and the flange portion edge winding lower mold member 8 A flange formed by a flange-molded upper mold member 6 cut into a shape. In Nji edges winding upper and lower mold member to mold the flange portion F to the arcuate edge winding shape. FIGS. 5 and 6 are enlarged views of the flange edge winding member shown in the above figure. FIG. 5 shows one flange portion between the container molded lower mold member 5 and the flange molded lower mold member 7. In the case where the edge lowering mold member 8 is provided, FIG. 6 shows the container forming apparatus 2 in the case where two flange part edge lowering mold members 8 are provided in another embodiment. That is, as shown in FIG. 5, the flange-shaped lower mold member 7 is penetrated from the outer peripheral edge side of the flange portion F of the container shape 3A in a state where the container-shaped lower mold member 5 and the flange-shaped lower mold member 7 are molded and fixed. As shown in FIG. 6, a small arc-like shape sandwiched between a flange edge lowering mold member 8 and a flange molding upper mold member 6 provided so as to be movable up and down from the lower side of the container forming apparatus 2 as shown in FIG. While repeating the edge winding pressing process in small increments, the preceding flange part edge lowering mold member 8 that has finished pressing the flange part F does not interfere with the edge winding pressing process of the subsequent flange part edge lowering mold member. It is formed into a predetermined edge winding shape while being sequentially lowered from the outer peripheral edge side.
FIG. 7 shows a cross section of a container formed into a product shape after edge winding pressing.

  In the present invention, the paperboard member 1 cut into a blank shape for container molding as described above is connected to the bottom surface portion B, the side wall peripheral surface portion W and the outer peripheral edge of the container in the horizontal direction by the container molding upper and lower mold members. After forming into a container shape 3A that opens on one side, a small arc-shaped edge winding pressing process is performed in small increments from the outer peripheral edge side of the flange portion F while pressing the flange side wall peripheral surface side of the container shape 3A. While iterating, the product is molded into a product container with an outer peripheral edge.

Next, examples of the present invention will be described.
200 pieces of paperboard members cut out from a paper coated with a heat-resistant resin film into a 200 mm diameter container forming blank shape, each with a container forming apparatus shown in FIG. After forming the container shape with a diameter of 185 mm and a depth of 35 mm to connect the horizontal flange portion to the side wall peripheral surface and its outer peripheral edge, the container-shaped upper and lower mold members are used to apply pressure to the side wall peripheral surface of the container-shaped flange portion. On the other hand, a small arc-shaped edge winding pressing process was repeated twice from the outer peripheral edge side of the flange portion F, and a prototype was formed into a product container having an outer peripheral edge. For comparison, 100 paperboard members cut to the same size with paper quality are molded into a container shape for each sheet, and then the flange portion on the outer peripheral edge is edged with the same size by one edge winding process. A wound container was formed.
As a result, the container of the present invention in which the edge winding portion of the container was molded by a small pressing process was stably formed without breaking or breaking from the edge winding portion. . On the other hand, the container molded for comparison produced a springback due to excessive edge winding processing, the edge winding shape was not uniform, and there were many containers that were not provided for commercial use.

The invention's effect

  In the present invention as described above, the side wall peripheral surface side of the flange portion that becomes the outer peripheral edge of the side wall peripheral surface is sandwiched when molding from a paperboard member into a container, and the outer peripheral edge side is repeatedly pressed while being repeatedly pressed. By forming it into a wound shape, it can be formed into a uniform outer peripheral winding shape with or without uneven ribs on the bottom surface of the container, so that a paper container having moderately strong strength and rigidity can be provided. Can do. In particular, when the present invention is used for corrugated paper, it does not cause springback due to the influence of the corrugated direction of the corrugated paper and its perpendicular direction, it does not break at the edge winding part, and has excellent strength and formability. Can be molded into a container.

  In one Example of this invention, the partial cross section figure of the press molding apparatus before shape | molding from a paperboard member to a paper container is shown. FIG. 2 shows a partial cross-sectional view of a press forming apparatus for forming a paperboard member into a container shape. The partial cross section figure of the press molding apparatus which performs edge winding shaping | molding of the outer peripheral edge side of a container-shaped flange part is shown.   The partial cross section figure of the press molding apparatus which repeats a container shape flange part and performs edge winding molding is shown.   The flange part edge winding type member of the press molding apparatus shown in FIGS.   The partially expanded sectional view of another press molding apparatus in this invention is shown.   The partial cross section figure of the container which finished edge winding press processing is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Paperboard member 3A Container shape 4 Container shaping | molding upper die member 5 Container shaping | molding lower die member 6 Flange shaping | molding upper die member 7 Flange shaping | molding lower die member 8 Flange part edge winding lower die member B Bottom face part F Flange part K Flange part edge winding process Surface W Side wall peripheral surface

Claims (1)

  The bottom portion (B) is formed by sandwiching the container outer peripheral portion of the paperboard member (1) cut into the container forming blank shape with the flange-shaped upper and lower mold members and bulging the container bottom corresponding portion with the container molded upper and lower mold members. ), The side wall peripheral surface portion (W) and the outer peripheral edge thereof are connected to the flange portion (F) in the horizontal direction and formed into a container shape (3A) that opens on one side, and then the container is formed with the container forming upper and lower mold members. A flange-shaped edge winding surface (K) having an arc cross-sectional shape is provided on the upper end side surface of the container-molded lower mold member (5) while surface pressure is applied to the side surface of the flange-shaped side wall of the container. One or two or more flange edge wrapping lower mold members (8) and the container molded lower mold member which are moved up and down with the upper end portion thereof having an arc cross-sectional shape between (5) and the flange molded lower mold member (7). (5) Flange edge winding surface (K) and flange edge Flange-formed upper mold member (7) notched into two or three or more arc-shaped cross-sectional shapes that press the flange portion (F) of the container shape (3A) at a position opposite to the lower mold member (8) ), And is formed into an arcuate edge winding shape while repeating edge winding pressing in a small arc shape from the outer peripheral edge side of the flange portion (F). Molding method.

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