JPH0433210Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a mold used in a continuous filling packaging method in which a plastic film is air-formed and then the molded container is continuously filled with contents and hermetically sealed. It is something.

(Prior Art) As shown in FIG. 1, in the conventional continuous filling and packaging method, a lower plastic film 1 in a rolled up state is heated, and a container is formed by vacuum forming or pressure forming in a forming section 2. After filling the molded container with the contents in the filling section 3, the upper plastic film 5 is placed over the opening of the container in the sealing section 4, and the periphery of the opening is heat-sealed to form a predetermined shape. I found a way to punch it out. In the above molding method, the mold in the molding part and the seal pedestal and mold in the sealing part are
I was using different ones. In this way, in the conventional continuous filling and packaging method, since separate molds and seal pedestals are used, there is a gap of at least 0.3 mm between the seal pedestal and the container, as shown in Figure 2. It was necessary to provide a clearance of 6.
If the clearance 6 is not provided and a seal pedestal 7 of the same size as the mold in the molding section is used, even a slight shift of the container 8 will cause the end of the seal pedestal 7 to touch the container, resulting in damage to the container. This is because there were cases where it was deformed. On the other hand, if the seal pedestal 7 provided with the clearance 6 is used, there is no risk of the container being deformed during sealing, but a sufficient seal cannot be achieved unless the width of the flange around the container is increased. That's fine, but even containers with a small filling capacity end up with wide flanges, resulting in an unsightly appearance.
Therefore, in order to solve this problem, the applicant devised a method in which the mold was divided into two parts in the height direction, and the upper part was transported together with the molded container and used as a sealing pedestal. (See Figure 3). The mold used in this continuous filling and packaging method is divided into a seal holder and a molding die, as described above, and is used to form a container by pressure forming. The mold was a split mold that could be moved up and down.

(Problem to be solved by the invention) However, since the mold in the above application is a divided mold, a gap 11 may occur at the interface where the seal pedestal 9 and the molding die 10 engage. If a container is molded with such a gap 11, the molded plastic film will enter the gap due to the compressed air used for pressure forming, resulting in a convex deformed portion. For this reason, the pressure-formed container cannot have a predetermined shape, and it has also become difficult to remove the molded container from the mold. The present invention has been made to solve the above problems.

(Means for Solving the Problems) That is, the present invention provides a seal pedestal that is used in air pressure forming used when forming a plastic film into the shape of a container, etc., and that moves together with the container formed by air forming. The mold includes a vertically movable mold that engages the seal pedestal and the interface with a gasket interposed therebetween, the mold having a balance air intake port on an outer side surface of the seal pedestal, A plurality of balance air outlets connected to the air intake and located between the container to be molded and the packing are formed, and a balance air intake and a balance air outlet are also provided in the molding mold at the same position as the seal holder. This is a mold characterized by the fact that it was formed.

(Function) In the molding section, when the plastic film is molded into the shape of a container, the mold is raised until it engages with the seal pedestal. A packing exists at the interface between the seal holder and the molding die, creating a gap between the seal holder and the molding die, but the packing maintains an airtight state between the packing and the container to be molded. . To mold the container, compressed air is sent in and when the container begins to be molded, air is supplied from the balance air intake. This balance air is adjusted according to the pressure of the compressed air introduced for container molding. With the wall surface of the container to be molded as a boundary, the force of the compressed air and balance air for molding prevents the plastic film from entering the gap between the seal pedestal and the molding die.

(Example) As shown in FIG. 4, the mold of the present invention has a seal pedestal 9 on which the plastic film is conveyed, and below the seal pedestal 9 is a mold 10 that is movable up and down. This is a mold that is divided into parts.
A packing 14 is arranged at the interface where the molding die 10 and the seal holder 9 engage, and the packing hermetically partitions the outside of the packing and the space on the molding container side, which is the inside of the packing. A balance air intake port 12 is located on the outer side surface of the seal holder 9, connected to the balance air intake port 12, and a plurality of balance air intake ports 13 are formed on the surface located between the container to be molded and the packing 14. There is. In the mold as well, the balance air intake port 12 is located on the outer side surface, and the balance air outlet port 13 is also located at the same position facing the same boundary as the balance air outlet port 13 of the seal pedestal 9.

After the plastic film to be pressure-formed is heated, it is continuously conveyed onto the seal pedestal 9. Once the plastic film is in place, the mold 10 is moved upward until it engages the seal cradle 9. Since the container is formed under pressure in a manner similar to conventional methods, the upper part of the plastic film is sealed, for example, a processed plug pushes the plastic film into the mold and pressurized air is introduced into the molding section. When the container begins to be molded, air is supplied from the balance air intake port 12 of the seal pedestal 9 and the molding die 10, and air is supplied from the balance air intake port 13 to the seal 14.
and the container to be formed. The pressure of this air can be adjusted depending on the pressure of the compressed air introduced for air pressure molding. By air,
The pressures on the inside of the molding container and on the outside of the packing are balanced, and the plastic film enters the gap 11 between the seal pedestal 9 and the molding die 10, so that no convex deformation occurs. When the container is molded, the mold 10 moves downward. The seal pedestal 9 located above the molded container moves together with the molded container to the contents filling section and close sealing section in the next step.

(Effects of the invention) As described above, the present invention forcibly creates a gap at the interface between the seal pedestal and the molding die, uses the packing to seal the gap on the container side, and creates a sealed space. This mold prevents plastic film from getting into the gaps by supplying air to the mold. With this configuration, even with a divided mold, molding defects will not occur.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing a conventional continuous filling and packaging method, Fig. 2 is an explanatory diagram of the seal part in Fig. 1, Fig. 3 is a sectional view of a conventional split mold, and Fig. 4 is an explanatory diagram of the conventional continuous filling and packaging method. A sectional view of the invented mold, FIG. 5, is a partially enlarged view of FIG. 4. 9... Seal pedestal, 10... Molding die, 11...
...Gap, 12...Balance air intake, 13
...Balance air outlet, 14...Patsukin.

Claims (1)

[Scope of utility model registration request] A seal pedestal that is used for air pressure forming when molding plastic film into the shape of a container, etc., and moves together with the container formed by air pressure forming, and is engaged with the seal holder with a packing interposed at the interface. The mold is composed of a molding mold that can be moved up and down, and has a balance air intake on the outer side of the seal holder, which is connected to the balance air intake and is connected to the seal between the container to be molded and the packing. A mold characterized in that a plurality of balance air intake ports are formed at the same position as the seal pedestal, and a balance air intake port and a balance air exit port are also formed in the mold at the same position as the seal pedestal.