JPH0243621B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a container including a body having a rectangular cross-sectional shape, and particularly relates to a method for manufacturing a container including a body having a polygonal cross-section. While winding it in a cylindrical shape on a mandrel whose constituent sides are slightly curved inward, the overlapping parts are glued together and a closing member is fixed to one open end, then the suction hole provided in the mandrel is used. The method is characterized in that the body member is recessed to match the cross-sectional shape of the mandrel to form a polygonal shape, and is suitable as a method for manufacturing paper containers for high-temperature filling such as youth products.

Conventionally, in paper containers for high-temperature filling such as J-use, the body of the paper container has a cylindrical shape to prevent denting and irregular deformation of the container due to the negative pressure phenomenon caused by the cooling of the filling after filling and sealing. The idea of providing ruled lines is known. However, even in the case of containers with ruled lines on the body, they do not necessarily deform (deform) into regular shapes due to negative pressure phenomena, and may deform ungainly regardless of the ruled lines, resulting in poor quality and appearance. A problem arose in that it was damaged.

In order to solve this problem, a method has been considered in which the body with the above-mentioned ruled lines is indented in advance along the ruled lines before filling. A conceivable method is to fit the body into a mandrel with a polygonal cross-section and press the body from the outside by some mechanical means, but in the present invention, the body is sucked from the inside of the mandrel to create a recess. I thought of a model that would let me do it.

The present invention will be explained in detail based on the embodiments shown in the drawings. First, a body member 1, which has a rectangular shape as shown in FIG. 1 and is made of a laminated material made of a combination of at least two of paper, synthetic resin, and metal foil, is made of a rectangular shape as shown in FIGS. 2 to 4. Each side of the polygonal shape is concave inward to form a curved surface 3, and the boundary between adjacent curved surfaces 3 and 3 is a protrusion 4, so that it has a cross-sectional shape like a starfish, and each of the curved surfaces 3 A suitable number of small holes 6 are provided on the surface of the mandrel M which communicate with the suction hole 5 provided in the axial direction at the center, and a presser foot 8 is provided at the upper end of the mandrel M with a packing material 7 interposed therebetween. The mandrel M is rotated and wound by holding the end thereof with a gripping tool (not shown) provided on the mandrel M.
Next, the overlapping parts are glued together using ultrasonic sealing or the like to form a cylinder, and a gap closing member 2 is attached to one open end of the cylinder.
The body member 1 is then fixed to the mandrel M by vacuum suction through the small hole 6 by a vacuum suction source (not shown) that communicates with the suction hole 5 through the hole 9 provided in the center of the presser foot 8 of the mandrel M. Concave along the curved surface 3 of M. As a result, the body member 1 has a ridge line 10 at the point where it hits the protrusion 4 of the mandrel M.
As shown by diagonal lines in FIG. 3, a prismatic (triangular or larger) body 11 matching the cross-sectional shape of the mandrel M is formed.

A youth etc. is inserted from the other open end of the prismatic body 11 thus completed.
The assembly of the container C is completed by filling the container at a temperature of about 90° C. and fixing another gap closing member 12.

In addition, regarding the mandrel M, if small holes 6' are provided not only on the curved surface 3 but also on the protruding part 4, the ridge line 10 of the body part 11 can be formed more clearly.

Since the present invention is configured as described above, it has the following excellent practical effects.

(b) Unlike the conventional method of pressing the body member from the outside on a mandrel by mechanical means, the body member is pressed from the inside of the mandrel by vacuum suction without any other jig or the like coming into contact with the body member. Since it is designed to be recessed, the surface of the body member will not be damaged or wrinkled, and it can be accurately formed into a polygonal shape without damaging its appearance.

(b) Since there is no need to provide ruled lines on the body member as in the past, the number of steps can be reduced, and there is no need to align the body member when winding it around a mandrel. Therefore, the operation is simple and the work efficiency is high.

(c) In the conventional pressing method, creases are created in the body member by moving the jig, so if you focus on one point on the body member, the jig passes only once, whereas in the method of the present invention, the body member is folded by vacuum suction. Since the force is applied to the entire body member at the same time, it is possible to take a long time to shape the shape, and it is possible to form the shape into an accurate square shape.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Figure 1 is a developed plan view of a container body member according to the present invention, Figure 2 is a perspective view of a mandrel used in the present invention, and Figure 3 is a perspective view of a mandrel used in the present invention.
The figure is a cross-sectional view showing a state in which the body member is wound around the mandrel in Figure 2 and is suctioned, and Figure 4 is a longitudinal cross-sectional view of the same.
FIG. 5 is a perspective view of a paper container manufactured according to the present invention. 1... Trunk member, 2... Bottom member, 3... Curved surface,
4...Protrusion, 5...Suction hole, 6,6'...Small hole,
7... Packing, 8... Presser foot, 9... Hole, 10
...Ridge, 11...Body, 2, 12...Closing member.

Claims (1)

[Claims] 1. In manufacturing a container in which closing members are provided at the upper and lower opening ends of a rectangular cylindrical body, the body member, which has no ruled lines, is made into a curved surface by recessing each side of an arbitrary polygon inward. A surface having a cross-sectional shape and formed by each of the sides has a small hole leading to a central suction hole, and is wound into a cylindrical shape on a mandrel provided in a curved surface and a protruding portion, and the overlapping portions are glued, A closing member is fixed to one open end, and then the body is recessed to match the cross-sectional shape of the mandrel by vacuum suction through the small hole using the suction hole of the mandrel.
A method for manufacturing a rectangular cylindrical container, characterized in that compressed air is then sent from the small hole through the suction hole to separate the body from the mandrel, and a closing member is provided at the other open end.