JPS60166444A - Method of assembling bottom of paper vessel - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for assembling the bottom of a paper container for storing milk, juice, alcohol, other soft drinks, etc.

(Prior art) This type of paper container is made by placing a paper container pasted onto a tube in advance on a turret-like mandrel, and after the bottom part of the paper container is assembled, it is discharged onto a container, filling the container with liquid, and FIG. 3 does not show a general paper container 10 manufactured. The bottom part 12 is provided with a fold as shown in FIG. 2, and assembled by folding the left wall 14 over the right wall 16, folding the whole into a flat shape, and gluing the walls together. Adhesion is performed by heating and melting a heat-sealing adhesive layer (for example, polyethylene resin) that has been previously applied to the inner and outer surfaces of the paper container. In order to assemble such a bottom, it is necessary to create a crease in advance. Conventionally, this bottom is folded immediately after the paper container is placed on a turret-shaped mandrel, and then the bottom is folded. was being heated.

(Problem to be solved by the invention) On the other hand, the heat-sealable adhesive layer on the inner surface of the paper container prevents the liquid content from penetrating into the paper layer, and the heat-sealable adhesive layer on the outer surface improves the appearance of the container. At the same time, these two heat-sealing adhesive layers prevent outside air from entering the container, so heating of the bottom only needs to be applied to the part of the bottom that will be folded and bonded together. Care must be taken not to heat and melt the heat-sealable adhesive layer in the area. However, since various base materials with different layer configurations and thicknesses are used in paper containers, the return of the bottom after folding is not constant, making it difficult to always heat only the bonded portion.

(Means for Solving the Problems) The present invention solves the above problems, and includes a step of heating the bottom of the paper container after covering the paper container on a turret-like mandrel, and To provide a method for assembling the bottom of a paper container, in which the bottom of the paper container is assembled by sequentially performing a step of forming a crease, and a step of folding, pressing and fusing the bottom with the crease.

(Example) Embodiments of the present invention will be described below based on the drawings.

1 and 2 show an apparatus for carrying out the method according to the invention. In the figure, reference numeral 18 denotes a paper container supply section, in which a large number of paper containers 20 pasted into tubes and folded flat are stacked. One side of the peripheral wall of the flat paper container is sucked by the suction cup 22 and the paper container is taken out one by one from the gauge 24, and while the paper container is being taken out, the adjacent surface of the paper container is pressed against a fixing member (not shown). It is then expanded into a square column shape and set on the supply table 26. The paper container is then capped onto the mandrel 32 by a member 30 that reciprocates along the guide 28. In this case, the mandrel 32 is a vertical turret, and as shown in FIG. 2, two sets of turrets rotate intermittently about an axis. Six mandrels are provided on the - group of turrets, and the paper container supply section 1 is located at the stop position of these mandrels.
8. The first heater 34, the second heater 36, the folding device 3, the folding pressurizing device 40, and the discharging device 42 are arranged in this order in the rotational direction.

Next, as shown in FIG. 1, when the paper container is placed on the mandrel 32, the mandrel 32 rotates 176 times, and the adhesive layer on the inner and outer surfaces of the bottom of the paper container is heated and softened by the first heater 34.
In the next 176 revolutions, the second heater 36 melts it well. At this time, the bottom of the paper container is not bent and maintains a square prism shape, and since the position of the bonded portion is constant, it is possible to easily heat only this bonded portion. Next, the mandrel 32 reaches the position of the crease imparting device buttock 8, where the bottom of the paper container is creased as shown in FIG. Push to the 32 side = J is removed and glued.

After the paper container with its bottom folded is extracted from the mandrel 32 by the ejection device 42, it is delivered to the receiver 62 of the container 60 below. The ejection device 42 is equipped with a pair of clamps and lowers the paper container on the mandrel 32.
Then, the paper container is rotated 90 degrees and another presser (not shown) is lowered to insert the paper container into the receiver 62. The conveyor 60 works intermittently to send the paper containers to subsequent processes such as the next filling process and sealing process.

Here, as shown in FIG.
=j A first heat retaining device 44 may be provided between the folding device 38 and a second heat retaining device 46 may be provided between the folding device 38 and the folding and pressing device 40. This means that the paper container is heated to the first heater 3.
4, second heater 36, folding device 38, folding hW
The heated bottom part is cooled by the outside air when moving between the pressure devices 40, and the adhesive layer is insufficiently melted during folding and pressurization, resulting in incomplete bonding, resulting in sufficient sealing of the container. It is effective when it is not possible to obtain

As shown enlarged in FIGS. 6 and 7, the first heat retaining device 44 includes a cover 48 provided along the travel trajectory at the bottom of the paper container, and a heater 50 provided inside the cover 48 along the trajectory. It is what it is. The heater 50 is provided along the center of the bottom 12, as shown in FIG. 7, to prevent the heated bottom 12 from being cooled down.

As shown enlarged in FIGS. 8 and 9, the second heat retaining device 46 also has a cover 52 along the running trajectory of the bottom portion 12 of the paper container. A guide 54 is provided for folding the folded bottom portion 12, and a heater 56 is provided at a position somewhat closer to the folding and pressurizing device 40 side. The bottom portion 12 heated by the heater 56 is prevented from being cooled down.

Note that the temperature of the atmosphere used by the heaters 50 and 56 is, for example, 30 to 40°C.

(Effects) As described above, in the present invention, since heating is applied before the bottom of the paper container is creased, only the bonded portion can be heated at all times. Therefore, we are able to create paper containers with extremely high sealing properties that will not leak the contents due to heating and melting the adhesive layer on other parts or spoil the contents due to the intrusion of outside air.
It has the advantage that it can be easily manufactured without damaging the appearance.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view of a paper container bottom assembly device for carrying out the present invention, FIG. 2 is a schematic plan view of the paper container bottom assembly device, and FIG. 3 is a perspective view of an example of a paper container. Figure 4 is a perspective view showing the state where the bottom of the paper container is folded;
The figure is a schematic front view showing a modified example of the &:Il standing device at the bottom of the paper container, FIG. 6 is a schematic front view of the first heat retention device shown in FIG. 5, and FIG. 7 is a schematic front view of the first heat retention device shown in FIG. Arrow sectional view, No. 8
The figure is a schematic front view of the second heat retention device shown in FIG. 5, and FIG. 9 is a sectional view taken along the line IX-IX in FIG. 8. 10... Paper container 12... Bottom part 18... Paper container supply section 32... Mandrel 34... First heater 36... Second heater 38... Crease imparting device 40... Folding pressure device 42...Discharge device 44...First heat retention device 46...Second heat retention device 60...Conhair patent applicant Dai Nippon Printing) Shu Shikikai '43-Agent Patent attorney Atsumi Konishi No. 1 Fig. 40"'- M Fig. 2 Fig. 18b Fig. 3 Fig. 5 Fig. 7 Fig. 6 Fig. 9 Fig. 8

Claims (1)

[Claims] In a method of assembling a paper container pasted onto a cylinder having heat-sealable adhesive layers on the inner and outer surfaces on an intermittently rotating turret-like mandrel, the bottom of the paper container is attached to the turret-like mandrel after the paper container is placed on the turret-like mandrel. The bottom of the paper container is assembled by sequentially performing a heating process, a process of forming a crease on the heated bottom, and a process of folding the folded bottom and pressurizing and fusing it. A special method for assembling the bottom of paper containers.