JPH04161317A - Container molding device - Google Patents

Abstract

PURPOSE:To press a flange section into the given thickness by providing a flange presser for pressing the flange section to a peripheral edge protruding section of a bottom force in a top force and also providing a spacer between the top force and the flange presser. CONSTITUTION:A flange presser 23 for pressing a flange section 15 of a container main body 14 to a peripheral edge protruding section 32 is provided on the outside of a plug 22 of respective top force 21, and a spacer 24 is fixed on the upper face of the flange presser 23. The bottom force 31 is brought close to the top force 21, and a heated laminate material 30 is cut between a cutting section 32a of the peripheral edge protruding section 32 and cutting section 21a of the top force 21 to form the outer periphery of the flange section 15. Simultaneously the flange section 15 is cut between the peripheral edge protruding section 32 on the side of a bottom force 31 and the flange presser 23. In that case, the position of the bottom force 31 close to the top force 21 is fixed by the dead spot of a cam driving the bottom force 31. The flange section 15 can be pressed by means of the height of spacer 24 and the dead spot of the bottom force, and thermoforming process and the pressing process of the container main body can be carried out simultaneously by said arrangement.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a container forming apparatus for making a plastic container body.

(Prior Art) Metal containers, such as metal cans, have various shapes, but can be classified into three-piece cans and two-piece cans based on the structure of the can body. A 3-piece can, also known as a tin solder can, has a cylindrical body, lid, and bottom sealed with double seams.

On the other hand, a two-piece can is also called a stamped tin can, and has a structure in which the body and bottom (container body) are integrally molded, and the lid is double-sealed.

These metal cans are used as food packaging containers for various canned foods, juices, soft drinks, jams, dried foods, etc., and are rigid containers with particularly excellent sealing and preservation functions. However, metal cans have the following points to be improved. That is, (1) Since it is a metal can, there is a limit to how much it can be made lighter.

■ If it is crushed by an impact, it will not recover and will be deformed.

■ Compared to plastic containers, the energy cost of manufacturing them is higher.

■ If the display effect of the container exterior is made of metal, it cannot be changed freely, and the only means of exterior packaging is printing.

■ It is impossible to create transparent containers that allow the contents to be checked without opening the can.

In order to solve these drawbacks of conventional metal cans,
2. Description of the Related Art Containers with metal lids are known in which the peripheral edge of a metal lid is double-wound to the flange of a plastic container body that stores contents therein.

In addition, as a method for manufacturing a plastic container body, a plastic laminate having the thickness necessary for forming the container is heated by a general thermoforming method, and a molded product of the container body having a flange part is used using a mold. A method of forming (sheet forming) is known.

This molding method will be explained with reference to FIG.

First, a plastic laminated material 30 having a thickness necessary for forming containers is heated with a heating machine 41, and a plurality of plastic container bodies 14 are formed by a general thermoforming method using a mold 42.
A molded article 40 consisting of the following is molded.

The body of each container body 14 constituting the obtained molded product 40 has a thickness and strength sufficient to withstand the pressure applied during double seaming. However, the flange part is too thick and is not suitable for double seaming, so a pressing process is required for the flange part.

・In other words, the container bodies 14 constituting the molded product 40 are separated one by one, and then the thickness of the flange portion is reduced using a press device (not shown) (pressing process), and the thickness of the flange is reduced using a cutting device (not shown). By cutting the width of the flange portion to a predetermined width (cutting step), a container body 14 that can be double-sealed is obtained.

(Problems to be Solved by the Invention) As described above, a plastic container body having a flange portion is thermoformed by a general thermoforming method, and then the thickness of the flange portion is reduced using a press machine. It is obtained by cutting the outer periphery of the flange portion using a cutting device.

However, when the thickness of the flange portion is reduced using a press device and the outer circumference of the flange portion is cut using a cutting device after thermoforming with a mold, the thickness and width may be reduced due to variations in the dimensions of the individual flange portions of the container body 14. It becomes difficult to achieve a predetermined accuracy.

In addition, since the container body is thermoformed and then pressed and cut, the number of manufacturing steps increases accordingly, leading to an increase in container cost.

The present invention has been made in consideration of these points,
It is an object of the present invention to provide a container forming device that can quickly and accurately create a flanged container body.

[Structure of the invention]

(Means for Solving the Problems) The present invention includes an upper mold having a plug, and a lower mold having a container shape that approaches the upper mold to a predetermined position and receives the plug, and is made of a plastic laminate material. In a container forming apparatus for thermoforming a container body having a flange part, a peripheral protrusion is provided at the opening peripheral part of the lower mold, and a flange presser is provided in the upper mold to press the flange part against the peripheral protrusion. The container forming apparatus is characterized in that a spacer is provided which is movable forward and backward and defines the thickness of the flange portion between the upper mold and the flange presser.

(Function) According to the present invention, when the lower mold approaches the upper mold, the peripheral protrusion of the lower mold presses the flange presser through the flange portion of the container body, and the flange presser presses the flange presser upward through the spacer. It stops when it comes into contact with the mold. Further, by bringing the lower die closer to the upper die to a predetermined position, the flange portion can be pressed to a predetermined thickness between the flange presser and the peripheral protrusion.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

First, a plastic container body and a container with a metal lid using this container body will be briefly explained with reference to FIG.

As shown in FIG. 3, the container body 14 includes a body 14a having an opening at the top, a bottom 14b, and a flange 15 provided at the periphery of the opening at the top of the body 14H and protruding outward in the radial direction. The container body 14 is made entirely of plastic.

The container 10 with a metal lid is obtained by storing the high-temperature contents 19 inside the container body 14 having such a structure and wrapping the peripheral edge 12 of the metal lid 11 around the flange portion 15.

Among these, the metal lid 11 is made of aluminum, for example, and the plastic container body 14 is made by thermoforming a plastic laminated material using a container forming apparatus to be described later.

Next, the container forming apparatus will be explained with reference to FIGS. 1 and 2.

As shown in FIG. 1, the container forming apparatus 20 includes a plurality of upper molds 21 having plugs 22 inside, and a lower mold 31 having a plurality of container shapes that can be approached to a predetermined position with respect to the upper molds 21. It is equipped with

Among these, the upper mold 21 is fixed, while the lower mold 31 is movable in the vertical direction.

Further, each plug 22 is supported by a plug support rod 26, and each plug support rod 26 is connected to a plug drive cylinder 28 via a horizontal rod 29. Therefore, by driving the plug drive cylinder 28, each plug 22 is moved in the vertical direction within the corresponding upper die 21.

On the other hand, a peripheral protrusion 32 is provided at the opening periphery of the lower mold 31 so as to protrude upward and can freely enter into the upper mold 21 . Furthermore, cutting portions 32a and 21a are formed on the outer surface of the peripheral protrusion 32 and the inner surface of the upper die 21, respectively, for sliding against each other and cutting the outer periphery of the flange portion 15 of the container body 14 (see FIG. 2(a)). (b)(c)).

Further, as shown in FIG. 1, each lower mold 31 is provided with a push-up pin 33 for taking out the molded container body 14 from the lower mold 31.

On the other hand, a flange presser 23 that presses the flange portion 15 of the container body 14 against the peripheral protrusion 32 is provided within each upper mold 21 and outside the plug 22 so as to be movable up and down. This flange retainer 23 is adapted to move independently of the plug 22. Further, a spacer for regulating the thickness of the flange portion 15 is fixed to the upper surface of the flange presser 23, and a spacer is provided between the flange presser 23 and the upper die 21 to urge the flange presser 23 downward. spring 25
Or installed.

Next, regarding the operation of this embodiment having such a configuration,
This will be explained with reference to FIGS. 2(a), (b), and (c).

First, a plurality of lower molds 31 are arranged at predetermined intervals with respect to a plurality of upper molds 21, and a plastic laminate 30 is transferred between them (FIG. 2(a)). In this case, the laminated material 30 is heated in advance to a temperature at which it can be molded in a previous step.

Next, the lower mold 31 rises and approaches the upper mold 21. In this case, the laminated material 30 is cut between the cut portion 32a of the peripheral protrusion 32 and the cut portion 21a of the upper mold 21, and the flange portion 1
5 is determined. At the same time, the flange portion 15 is pressed and held between the peripheral protrusion 32 and the flange retainer 23 by the urging force of the spring 25 (FIG. 2(b)).

The lower mold 31 then continues to rise further, and the peripheral protrusion 32 of the lower mold 31 pushes the flange presser 23 upward via the flange portion 15 against the force of the spring 25. Thereafter, the spacer 24 comes into contact with the inner surface of the upper mold 21, and the movement of the flange presser 23 is stopped.

In this state, the lower mold 31 further rises, and the flange portion 15 is pressed between the peripheral protrusion 32 on the lower mold 31 side and the flange presser 23 (FIG. 2(C)). In this case, since the approach position of the lower mold 31 to the fixed upper mold 21 is determined by the dead center position of a cam (not shown) that drives the lower mold 31, the height of the spacer 24 and the lower mold having a container shape The flange portion 15 can be pressed to a predetermined thickness by setting the dead center position of the flange to a predetermined thickness.

During this time, by driving the plug drive cylinder 28, the plug 22 is lowered and entered into the lower mold 31.

At the same time, by blowing compressed air from the plug 22 side, the body 14a and bottom 14b of the container body 14 are thermoformed. In this way, the plastic container body 14
is obtained.

Subsequently, the lower mold 31 descends and separates from the upper mold 21. Thereafter, the container body 14 in the lower die 31 is pushed upward by the push-up pin 33 and transferred outward by a suitable transfer means.

〔Effect of the invention〕

As explained above, according to the present invention, a plastic container body is thermoformed from a laminated material using a container molding device, and at the same time, a flange portion is accurately pressed to a predetermined thickness between a flange presser and a peripheral protrusion. I can do it. As described above, since the thermoforming process and the pressing process of the container body can be performed simultaneously, it is possible to significantly reduce the manufacturing process compared to a case where the thermoforming process and the pressing process are performed separately.

[Brief explanation of the drawing]

FIG. 1 is a side view showing an embodiment of the container forming apparatus according to the present invention, FIGS. FIG. 4 is a side view showing a container with a metal lid, and FIG. 4 is a diagram showing a conventional process of manufacturing a molded product of the container body by thermoforming by means of sheet forming. 10... Container forming device, 21... Upper mold, 22...
Plug, 23... Flange retainer, 24... Spacer, 25... Spring, 30... Laminated material, 31... Lower die, 32... Peripheral protrusion. Applicant's agent: Yu Sato Figure 3 Figure 4

Claims (1)

[Claims] 1. A container comprising an upper mold having a plug, and a lower mold having a container shape that approaches the upper mold to a predetermined position to receive the plug, and having a flange portion made of a plastic laminated material. In a container forming apparatus for thermoforming a main body, a peripheral protrusion is provided at the opening peripheral part of the lower mold, and a flange presser is provided in the upper mold to press the flange part against the peripheral protrusion, and is movable back and forth. A container forming apparatus characterized in that a spacer is provided between the upper die and the flange presser to define the thickness of the flange portion. 2. The container forming apparatus according to claim 1, wherein cutting portions for cutting the outer periphery of the flange portion are formed on the outer surface of the peripheral protrusion of the lower mold and the inner surface of the laminate side end of the upper mold. 3. The container forming apparatus according to claim 1, further comprising an elastic member interposed between the upper die and the flange presser to press the flange presser downward.