JP2009029444A - Plastic container deforming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plastic container deforming method capable of easily performing the inward shrinkage/deformation of a bottom part of the plastic container. <P>SOLUTION: In the plastic container deforming method, an outwardly projecting bottom part of the plastic container 200 is subjected to the inward shrinkage/deformation by pressurizing the bottom part with a fluid 150. A plastic container deforming apparatus usefully performs the inward shrinkage/deformation of the bottom part without breaking the bottom part by pressurizing the bottom part without applying any excessive local shock. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for deforming the bottom of a plastic container.

Conventionally, when a plastic container is filled with high-temperature contents, the volume is reduced after the contents are cooled, and the bottom part is previously removed in order to prevent the side part of the plastic container from being deformed under reduced pressure. Fill the contents after protruding outwards, or press the inside of the plastic container while filling the contents to protrude outwards from the bottom, then return the shape of the bottom to the original after the contents cool down Thus, a method for eliminating the reduced pressure state has been proposed. For example, in Patent Document 1, a rod 502 is inserted into a plastic container 600, and the bottom is pressed from the inside to make the bottom convex (FIGS. 6A to 6D). Then, after the contents are cooled, the bottom portion is returned to its original shape by pressing the bottom portion from the outside with another rod 504 (FIGS. 7A to 7D). In addition, an invention related to a method of pressurizing the inside of a plastic container while filling the contents as in Patent Document 2 has been proposed earlier than the applicant.
International Publication No. 2004/028910 Pamphlet Japanese Patent Application No. 2006-098157 "Plastic container deformation device and plastic container deformation method"

  However, as described above, when the bottom of the plastic container 600 is pressed from the outside by the rod 504 after the contents are cooled, the speed of the rod 504 is inadvertently increased when the shape of the bottom is restored. In addition, since the impact at the time of contact with the bottom portion becomes large, the bottom portion may be damaged, and control is difficult.

  The present invention has been made to solve the conventional problems, and an object of the present invention is to provide a plastic container deforming device capable of easily deforming the bottom of a plastic container.

The plastic container deforming method of the present invention is a plastic container deforming method in which a bottom part protruding outward of the plastic container is contracted inward, wherein the bottom part is deformed and deformed by pressurizing with a fluid. To do.

Since the bottom portion of the plastic container protruding outward is pressurized by the fluid, it can be deformed inward without excessively applying a local impact to the bottom portion, so that there is no possibility of damaging the bottom portion.

Hereinafter, a plastic container deformation device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an outline of a manufacturing process of a product in which a plastic container (for example, a plastic bottle whose bottom portion can be inverted as shown in FIGS. 5 to 7) is filled.
The manufacturing process shown in FIG. 1 includes a bottom projecting process 10, a filling process 20, a cap mounting process 30, a tipping sterilization process 40, a cooling process 50, and a bottom restoring process 60. In the bottom projecting step 10, the bottom of the plastic container is projected to be deformed into a convex shape. In the filling step 20, a plastic container whose bottom is deformed into a convex shape is filled with high-temperature contents (for example, 85 degrees Celsius). In the cap mounting step 30, a cap is mounted on the head of the plastic container filled with the contents.
In the overturning sterilization process 40, the plastic container with the cap attached is overturned to sterilize the inner top surface of the cap and the inner surface of the nozzle portion. In the cooling step 50, hot water or cold water is sprinkled on the plastic container after the sterilization treatment for about 20 minutes to 40 minutes, and the contents are cooled to about 40 degrees Celsius. In the bottom restoration step 60, the projecting bottom of the cooled plastic container is degenerated and returned to its original shape.

  The plastic container deformation method in the present embodiment is used, for example, in the bottom restoration process 60 of the manufacturing process as described above.

2 to 4 are a cross-sectional view of the configuration of an apparatus for carrying out the plastic container deformation method and a diagram illustrating a process of deforming the bottom of the plastic container, FIG. 2 is a first process, FIG. 3 is a second process, FIG. 4 shows the third step. A plastic container deforming device 100 shown in these drawings includes a connection nozzle portion 102 as a tubular member, a cylinder 104 and a piston 106 as pressure generating devices, and a support portion 108.
Further, the pressure generator for carrying out the plastic container deformation method of the present invention comprises a cylinder member and a piston member that slides in contact with the inner wall surface of the cylinder member. The gas and / or liquid that is a fluid may be introduced into the plastic container.

According to this configuration, by sliding the piston member into the cylinder, the gas and / or liquid filled in the inner space of the cylinder is discharged to the bottom of the plastic container, and pressurizes the bottom of the plastic container. Thus, the bottom portion protruding outward can be contracted inwardly.
Further, the plastic container deforming device of the present invention is provided with a support part that supports and supports any one of the side part, shoulder part, neck part or head part (cap head part) of the plastic container, and the container bottom part is inwardly provided. The plastic container is supported from the upper side so as not to release the force that causes deformation.

In the first step shown in FIG. 2, the position of the plastic container 200 is fixed in a state where the shoulder portion is supported by the support portion 108. The space inside the cylinder 104 is filled with air 150 as a fluid.

The integrated connection nozzle portion 102, cylinder 104, and piston 106 move upward with power, and the upper end portion of the connection nozzle portion 102 contacts the bottom portion (grounding portion) of the plastic container 200. A sealing member such as an O-ring is provided at the upper end portion of the connection nozzle portion 102, while the upper end portion of the connection nozzle portion 102 and the bottom portion (grounding portion) of the plastic container 200 are in close contact with each other without a gap.

As described above, the upper end portion of the connection nozzle portion 102 and the bottom portion (grounding portion) of the plastic container 200 are brought into close contact with each other without any gap, so that the inside of the bottom portion of the plastic container 200, the connection nozzle portion 102, and the cylinder 104. This space becomes a continuous sealed space.

In the second step shown in FIG. 3, of the integrated connection nozzle portion 102, cylinder 104, and piston 106, only the piston 106 obtains power and comes into contact with the inner wall surface of the cylinder 104 to move inside the cylinder 104. It moves upward by sliding. Thereby, the air 150 filled in the inner space of the cylinder 104 is discharged toward the bottom of the plastic container 200.
Then, as shown in FIG. 4, due to the pressurization resulting from the introduction of air 150 into the bottom of the plastic container 200, the bottom of the plastic container 200 is pushed back inward by receiving the force of the pressure, resulting in a degenerated concave shape. At this time, since the shoulder part of the plastic container 200 is supported by the support part 108, the plastic container 200 can be supported without releasing the deformation force when the bottom part is deformed and deformed.

  As described above, in the plastic container deforming method of the present embodiment, the connecting nozzle unit 102, the cylinder 104, and the piston 106 integrated in the plastic container deforming apparatus 100 move upward, and the upper end of the connecting nozzle unit 102 is the plastic container. After the piston 106 slides in the cylinder 104, the air 150 filled in the inner space of the cylinder 104 becomes the bottom of the plastic container 200. By discharging inward, the bottom portion of the plastic container 200 is pushed back inward to form a concave shape that is degenerated.

  Therefore, unlike the case where the bottom of the plastic container 200 is pressed from the outside by a conventional rod, the bottom of the plastic container 200 can be easily damaged without being damaged by an impact when the tip of the rod and the bottom of the plastic container are in contact with each other. The bottom can be degenerately deformed.

  Further, in the plastic container deforming apparatus 100, since the support portion 108 supports the shoulder portion of the plastic container 200, the position of the plastic container 200 is fixed, and further, the plastic container 200 is deformed into a concave shape with the bottom portion retracted. Even in this case, the plastic container can be supported without releasing the deformation force of the bottom.

In addition, this invention can take not only the said embodiment but a various form.
For example, in the plastic container deforming device 100, the upper surface of the cylinder 104 is fixed to the sealing member of the connection nozzle portion 102 with an elastic film body instead of the O-ring, and the bottom of the plastic container 200 is fixed to the fluid 150 together with the elastic film body. You may press and deform | transform by pressurization.
Alternatively, an external compressor may be used as the pressure generator, and the bottom may be pressurized with a high-pressure fluid obtained by piping from the compressor.
Furthermore, in the manufacturing process, the bottom protruding step 10 in FIG. 1 may be omitted by using a plastic container whose bottom portion protrudes outward in advance (in this case, the bottom restoring step 60 is changed to a bottom deforming step). In addition, the plastic container bottom in a state of protruding outward only by changing the name is not changed inwardly, and the plastic container that has been pre-sterilized and washed, and the pre-sterilized content liquid, By carrying out in an aseptic environment, the content liquid temperature in the filling step 20 can be changed from high temperature to normal temperature (about 30 ° C.), and the bottom sterilization can be performed by omitting the overturning sterilization step 40 and the cooling step 40 The process may proceed to step 60, and the inside of the container may be positively pressurized by causing the plastic container bottom to contract inwardly.
In addition, the present invention may be used not to be in the manufacturing process as shown in FIG. 1 but to simply deform the bottom portion of the plastic container protruding outward inwardly.

  As described above, the plastic container deformation method according to the present invention can easily deform the bottom of the plastic container projecting outward after filling and sealing the content liquid inwardly, as a plastic container deformation device. It is useful to reduce the degree of decompression when cooling and selling after filling, sealing and sterilizing the contents liquid into a plastic container, or by increasing the internal pressure of the plastic container when selling after filling at normal temperature and sealing. It becomes possible to increase the strength of the container.

It is a figure which shows the outline of the manufacturing process of the product which filled the content in the plastic container. It is sectional drawing of a structure of a plastic container deformation | transformation apparatus, and a figure which shows the 1st process of bottom part deformation | transformation. It is sectional drawing of a structure of a plastic container deformation | transformation apparatus, and a figure which shows the 2nd process (initial stage) of bottom part deformation | transformation. It is sectional drawing of a structure of a plastic container deformation | transformation apparatus, and a figure which shows the 2nd process (late stage) of bottom part deformation | transformation. It is an expanded sectional view of the bottom part of the plastic container in which a bottom part can be reversed. It is a figure which shows the process of deform | transforming the bottom part of the conventional plastic container into a convex shape. It is a figure which shows the process of decompress | restoring the shape of the bottom part of the conventional plastic container.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Plastic container deformation | transformation apparatus 102 Connection nozzle part 104 Cylinder 106 Piston 108 Support part 150 Fluid (air)
200 Plastic container

Claims (1)

  A plastic container deformation method for deforming and deforming a bottom portion protruding outward of a plastic container inward, wherein the bottom portion is deformed and deformed by pressurizing with a fluid.

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