JPH04161318A - Container molding device - Google Patents

Abstract

PURPOSE:To manufacture a container main body with flange quickly and with good accuracy by providing a flange presser of a top force consisting of a flange corresponding section for pressing a flange to a peripheral edge protruding section between said two sections and a body section corresponding section for pressing a body section of container main body to the peripheral edge protruding section between said two sections. CONSTITUTION:A peripheral edge protruding section 32 movable into a top force 21 is provided on an open peripheral edge section of a bottom force 31, and a flange presser 23 consists of a flange corresponding section 38 being in contact with a flange section 15 of a container main body 14 and a body section corresponding section 39 positioned on the inner side of the radius direction of the flange corresponding section 38 and extending downwardly from the flange corresponding section 38. The flange section 15 is pressed to the peripheral edge protruding section 32 by the flange corresponding section 38 between said two sections, and a section 16 affecting the rolling work out of the body section of container main body 14 is pressed to the inner side face of the peripheral edge protruding section 32 by the body section corresponding section 39 between said two sections to regulate the thickness of said section 16. The flange section can be rolled on the peripheral edge section of a metal cover.

Description

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

(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 its weight reduction.

■ 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 a container 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.

That is, each container body 14 constituting the molded product 40 is
After that, a press device (not shown) is used to reduce the thickness of the flange portion (pressing process), and a cutting device (not shown) is used to cut the flange portion to a predetermined width (cutting process).
In this way, each container body 14 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 is reduced using a press device and the outer periphery of the flange is cut using a cutting device after thermoforming with a mold, the thickness and width of the flange may be reduced due to variations in the individual dimensions of the container body 14. It becomes difficult to achieve a predetermined accuracy.

Furthermore, since the container body is thermoformed and then pressed and cut, the number of manufacturing steps increases accordingly.

Further, as described above, the container body 14 is wrapped around a metal lid to create a container with a metal lid, but the part of the body of the container body that is affected by the seaming work (the seaming affected area) If it is too thick than the flange part, it will not be possible to perform the seaming operation stably.

The present invention has been made in consideration of these points,
It is an object of the present invention to provide a container forming apparatus that can quickly and accurately produce a flange-equipped container body, and can also make a portion of the container body near the flange a predetermined thickness.

[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 device for thermoforming a container body with a flange portion for producing a container with a metal lid, a peripheral protrusion is provided at the opening peripheral portion of the lower mold,
A flange presser that presses the flange portion is provided in the upper mold so as to be movable back and forth, and a flange corresponding portion that presses the flange portion between the flange presser and the peripheral protrusion, and a radially inner inner portion of the flange presser. The container forming apparatus is characterized in that it comprises a body corresponding part that is located on the side and presses the body of the container body between it and the peripheral protrusion.

(Function) According to the present invention, when the lower mold approaches the upper mold, the flange portion of the container body is pressed between the peripheral protrusion of the lower mold and the flange corresponding portion, and is made to have a predetermined thickness. A portion of the container body body near the flange portion is pressed between the peripheral protrusion and the body portion corresponding portion to have a predetermined thickness.

(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. 4, the container body 14 is composed of 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 14a 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 is shown in FIGS. 1 to 3.
explain.

As shown in FIG. 1, the container molding 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 on the outer periphery of 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 is provided on the upper surface of the flange holder 23 to define the thickness of the flange portion 15, and a spacer is provided between the flange holder 23 and the upper die 21 to urge the flange holder 23 downward. spring 25
is installed.

Next, regarding the structure of the flange retainer 23, see Figures 2 and 3.
This is explained in detail in the figure.

As shown in FIGS. 2 and 3, the flange retainer 23 has a flange corresponding portion 38 that contacts the flange portion 15 of the container body 14, and is located radially inward of the flange corresponding portion 38 and extends downward from the flange corresponding portion 38. The body portion corresponding to the body portion 39 extends to the body portion 39.

Of these, the flange corresponding portion 38 presses the flange portion 15 of the container body 14 against the peripheral protrusion 32.

In addition, the body corresponding part 39 presses the part of the body 14a of the container body 14 that is affected by seaming work (the seaming affected part) between the inner surface of the peripheral protrusion and reduces the thickness of this part. It stipulates that

Next, the shape of each part of the flange presser 23 will be explained with reference to FIG.

The width g of the flange corresponding portion 38 is: g−width of the flange portion 15+thickness between the body portion corresponding portion 39 and the inner surface of the lower die peripheral protrusion.

Further, the height T of the trunk corresponding portion 39 is T>counter sink t1. Here, the counter sink tt is a value shown in FIG.
The value is .

Further, the outer surface of the trunk corresponding portion 39 is inclined downwardly and inwardly, and the inclination angle θ is 0 to θ<6″.

The inner surface of the peripheral protrusion 32 on the lower mold 31 side has a shape that substantially corresponds to the flange corresponding portion 38 and the body portion corresponding portion 39 of the flange presser 23.

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 in a previous step.

Next, the lower die 31 rises and approaches the upper die 21. Thereafter, the laminated material 30 is cut between the cutting part 32B of the peripheral protrusion 32 and the cutting part 21a of the upper mold 21, and the flange part 15
The outer circumference of is determined. At the same time, the flange portion 15 is pressed and held between the peripheral protrusion 32 and the flange retainer 23 (FIG. 2(b)).

Thereafter, the lower mold 31 continues to rise further and pushes the flange presser 23 upward against the force of the spring 25 via the peripheral protrusion 32 or the flange 15 of the lower mold 31. Thereafter, the spacer 24 comes into contact with the inner surface of the upper die 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 upper surface of the peripheral protrusion 32 on the lower mold 31 side and the lower surface of the flange corresponding portion 38 of the flange presser 23 (Fig. 2 (C)
)). In this case, the lower mold 31 relative to the fixed upper mold 21
The approach position is determined by the dead center position of a cam (not shown) that drives the lower die 31, so by setting the height of the spacer 24 to a predetermined value, the flange portion 15 is pressed to a predetermined thickness. be able to.

At the same time, the seaming-affected part 16 of the body 14a of the container body 14, which is close to the flange 15, is pressed between the inner surface of the peripheral protrusion 32 and the outer surface of the body corresponding part 39. The thickness of the tightening affected area 16 is adjusted to a predetermined value.

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.

As explained above, according to this embodiment, at the same time as thermoforming the plastic container body 14 from the laminated material 30,
The flange portion 1 is held between the flange presser 23 and the peripheral protrusion 32.
5 to a predetermined thickness with high accuracy, and the width of the flange portion 15 can be made to a predetermined width. Furthermore,
The height of the body part corresponding part 39 is made larger than the countersink t1 between the seaming influence part 16 and the path length, and the height of the part corresponding to the body part 39 is made larger than the countersink t1 between the seaming influence part 16 and the length. Since the seaming-affecting portion 16 of the container body 14 is pressed, the seaming-affecting portion 16 can be reliably made to have a predetermined thickness. For this reason,
The flange portion 15 of the container body 14 can be securely and stably tightened by the metal lid peripheral portion.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to thermoform a plastic container body from a laminated material and at the same time press the flange portion to a predetermined thickness between the peripheral protrusion and the flange corresponding portion. Moreover, in this case, the portion of the container main body body near the flange that is directly affected by the seaming operation can be pressed to a predetermined thickness between the peripheral protrusion and the body corresponding portion. In this way, since the portion of the container body body near the flange can be made to have a predetermined thickness, the flange can be reliably wrapped around the peripheral edge of the metal lid.

[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. 2(a), (b), and (c) are views showing its operation, and FIG. FIG. 4 is an enlarged side view showing a protrusion, FIG. 4 is a side view showing a plastic container body and a container with a metal lid, and FIG. 5 is a conventional method of manufacturing a molded container body by thermoforming by sheet forming. It is a figure showing a process. 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: Yudai Sato, 4, Figure 5

Claims (1)

[Claims] 1. A container with a metal lid is made from a plastic laminated material, comprising 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. In a container forming apparatus for thermoforming a container body with a flange for use, a peripheral edge protrusion is provided at the opening periphery of the lower mold, a flange presser for pressing the flange is provided in the upper mold so as to be movable forward and backward; A flange corresponding part that presses the flange part between a flange presser and the peripheral protrusion, and a flange corresponding part that is located radially inward of the flange corresponding part and presses the body part of the container body between the peripheral protrusion and the flange presser. 1. A container forming apparatus comprising: a body-corresponding part; 2. The container forming apparatus according to claim 1, wherein the height of the body corresponding portion is greater than the length of the counter sink of the metal lid container. 3. The container molding apparatus according to claim 1, further comprising a spacer provided between the upper die and the flange holder to define the thickness of the flange portion.