JPH03297625A - Press device - Google Patents

Abstract

PURPOSE:To press a flange section of a plastic container main body with good accuracy by installing guides having a shape corresponding to a body section and a bottom section of the container main body in a press male mold and retaining elastically a press plate for pressing the bottom section of container main body on the inner side of the press male mold. CONSTITUTION:Guides 25-27 to be installed in a plastic container main body 45 are provided on a press male mold 21a, a cooling table 22 and the upper section of a cutting male mold 23a, and the guides 25-27 are provided with the shapes corresponding to a body section 47 and a bottom section 48 of the container main body 45 to fix the container main body 45 in the given position. A shaft 56 is disposed slidably in the axial line direction on an upper plate section 58 of a press female mold 21b and a press plste 55 is mounted on the lower end of the shaft 56. The body section 48 of the container main body 45 is pressed elastically by means of the press plate 55 and a spring 57 to fit the container main body 45 for the guide 25. Thus, a flange section 46 can be pressed with good accuracy between the press male mold 21a and the press female mold 21b.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a press device for pressing a flange portion of a plastic container body used in a container with 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 three-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 chest 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,
Containers with metal lids have been proposed in which the peripheral edge of a metal lid is wrapped around the flange of a plastic container body.

In addition, as a method for manufacturing a plastic container body, a plastic sheet having a thickness necessary for forming the container is heated by an intra-membrane thermoforming method, and a molded product of the container body having a flange portion is formed using a mold. A method has been considered in which the thickness of the flange is reduced (sheet forming), and then the flange is cut to a predetermined width. The reason why the flange portion is press-cut in this way is to perform appropriate seaming and tightening between the flange portion and the peripheral edge portion of the metal lid.

(Problems to be Solved by the Invention) As mentioned above, when manufacturing a plastic container body, in order to obtain a highly accurate container with a metal lid by properly seaming the periphery of the metal lid, It has been considered to press the flange portion of the container body to a predetermined thickness, and then cut the outer periphery of the flange portion to a predetermined width.

In this case, the pressing operation of the flange portion is performed by a press device consisting of a male press die and a female press die. In the actual pressing operation, the container body is first placed at a predetermined position on the male press die, and the flange portion is pressed between the male press die and the female press die.

However, there is a problem in that if the container body is not securely fixed at a predetermined position on the male mold, press wobbling occurs and the flange portion cannot be pressed with high precision.

The present invention has been made in consideration of these points,
It is an object of the present invention to provide a press device that can press a flange part of a plastic container body with high precision.

[Structure of the invention]

(Means for Solving the Problems) The present invention is a press device in which a flange portion of a plastic container body thermoformed by sheet forming is heated and pressed between a male press die and a female press die. , a guide having a shape corresponding to the body and bottom of the container body is attached to the male press die, and a pressing plate for pressing the bottom of the container body is elastically held inside the female press die.

(Function) When the male press mold and the female press mold approach each other, the pressing plate first presses the bottom of the container body toward the male press mold, and
The container body is mounted on the guide, and then the flange portion is pressed between a male press die and a female press die.

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

FIG. 1 is a diagram showing an embodiment of a press device according to the present invention, FIG. 2 is a diagram showing the entire press cutting device equipped with the press device, and FIG. 3 is a diagram showing a plastic container body. It is a diagram.

First, the outline of the entire press cutting device will be explained with reference to FIG. In FIG. 2, the press cutting device 10 is provided on a base 11 via a crank mechanism 12, and includes an intermediate bed 13 that reciprocates in the vertical direction. This intermediate bed 13 has three positions: an upper position, an intermediate position, and a lower position. Also, intermediate bet 1
An upper fixing base 15 is disposed above 3.

Further, as shown in FIG. 2, a male press die 21a is provided on the upper right side of the intermediate bed 13, and a female press die 21b is provided in the lower part of the upper fixing table 15 in correspondence with the male press die 21a. Press male die 21a and press female die 21
b forms a press device 21 according to the invention.

On the other hand, on the upper left side of the intermediate bed 13, there is a male cutting die 23a.
is provided, and a male cutting die 23 is provided at the bottom of the upper fixing base 15.
A cutting female die 23b is provided corresponding to the cutting die 23b, and a cutting device 23 is formed by the cutting male die 23a and the cutting female die 23b. Furthermore, a cooling stand 22 is provided at the center of the upper part of the intermediate bed 13.

Further, guides 25, 26° 27, which are mounted inside the plastic container body 45, are provided on the cooling stand 22 of the male press die 21a1 and the male cut die 23a. The guides 25, 26 and 27 have shapes corresponding to the body 47 and bottom 48 of the container body 45 shown in FIG. 3, and are used to fix the container body 45 in a predetermined position.

Furthermore, as shown in FIG. 2, on the right side of the upper fixing base 15,
A supply pipe 28 for supplying the container body 45 is provided, and a supply stand 30 is provided on the intermediate bed 13 in correspondence with the supply pipe 28. This supply pipe 28 supplies a container body 45 molded from a plastic sheet by a general thermoforming method to the supply table 30. Also, the upper fixed base 15
A discharge pipe 29 that communicates with the cut female mold 23b and discharges the container body 45 is provided on the left side of the container body 45.

Further, between the intermediate bed 13 and the upper fixing table 15, the container body 45 is sequentially moved in the horizontal direction from the supply table 30 to the press male mold 21a1 of the press device 21, the cooling table 22, and the cut male mold 23a of the cutting device 23. A conveying device 17 for conveying is provided.

Note that the base 11, crank mechanism 12, and intermediate bed 13 are covered as a whole with a cover 16.

Next, the press device 21 will be described in detail with reference to FIG.

The press male die 21a of the press device 21 is attached to the intermediate bed 13.
A guide 25 is attached to the male press die 21a via a press stand 36. Press male mold 21a
The press female die 21b presses the flange portion 46 of the container body 45 to make the flange portion 46 have a predetermined thickness, and each of the press female molds 21b has a heater 33 for heating the flange portion 46, 35 are provided respectively.

Furthermore, a cooling water channel 34 is formed within the guide 25 to cool the body 47 and bottom 48 of the container body 45. The cooling water flow path 34 communicates with an inflow path 51 and an outflow path 52 formed in the press table 36, respectively. Furthermore, the press table 36 has a vacuum tube 5 which is opened on the surface of the guide 25 and which holds the container body 45 by suction.
3 is formed.

On the other hand, the female press mold 21b has a substantially hollow cylindrical shape, and the guide 25 can be housed therein.

Further, a shaft 56 that extends through the upper plate portion 58 of the press female mold 21b in the axial direction is slidably disposed thereon. Further, a stopper 59 is attached to the upper end of the shaft 56, and a suppressing plate 55 is attached to the lower end of the shaft 56.

A spring 57 is interposed between the upper surface of the suppression plate 55 and the lower surface of the upper plate portion 58, and the spring 57 causes the pressure plate 55 to elastically press the bottom portion 48 of the container body 45. .

Next, the operation of this embodiment having such a configuration will be explained.

First, a plastic sheet having a thickness necessary for forming a container is heated in advance by a general thermoforming method, and a container body 45 having a flange portion 46 is formed using a mold. (Fig. 3) Next, this container body 45 is transferred to the supply table 3 through the supply pipe 28.
Then, the intermediate bed 13 is placed at an intermediate position, and the container body 45 is gripped by a grip (not shown) of the conveying device 17. Subsequently, the intermediate bed 13 is lowered to the lower position, and the container body 45 is transported by the transport device 17 to above the male press die 21a.

Subsequently, the intermediate bed 13 moves up through the intermediate position to the upper position, and the conveying device 17 separates from the container body 45.

In this case, first the suppression plate 55 is pressed against the bottom 4 of the container body 45.
8 is elastically pressed downward to attach the container body 45 to the guide 25. In this way, the suppression plate 55 presses the bottom part 48 of the container body 45 to attach it to the guide 25, so if, for example, the container body 45 that has been transported to the press device 21 is out of position with respect to the guide 25, However, the container body 45 can be reliably attached and fixed to the guide 25.

At the same time, the vacuum tube 53 opening on the surface of the guide 25 allows the container main body 45 to be brought into close contact with the guide 25 and to be fixed more accurately. Subsequently, the female press die 21b is lowered slightly by hydraulic pressure, and the flange portion 46 of the container body 45 is pressed between the male press die 21a and the female press die 21b, and the thickness of the flange portion 46 is reduced to a predetermined thickness. be adjusted.

In this pressing process, the flange portion 46 is connected to the heater 3 provided in the male press die 21g and the female press die 21b.
Since it is heated by 3.35 degrees, reliable pressing is performed.

The container body 45 with the flange portion 46 pressed by the press device 21 is then transported to the cooling table 22 and cooled there. Subsequently, the container body 45 is conveyed to the cutting device 23, where the outer circumference of the flange portion 46 is cut by the cutting device 23, and the width of the flange portion 46 is adjusted to a predetermined width.

〔Effect of the invention〕

As explained above, according to the present invention, the suppression plate presses the bottom of the container body toward the male press mold side and attaches the container body to the guide, so that the container body can be fixed at an accurate position on the guide. . Therefore, the flange portion can be pressed with high precision between the male press die and the female press die.

[Brief explanation of drawings]

FIG. 1 is a side view showing one embodiment of a press apparatus according to the present invention, FIG. 2 is a schematic view of the entire press cutting apparatus, and FIG. 3 is a side view of a container body to be pressed. 10... Press cut device, 21... Press device,
21a...Male press mold, 21b...Female press mold, 2
3... Cutting device, 25... Guide, 45... Plastic container body, 46... Flange portion, 47...
...Body part, 48...Bottom part, 55...Press plate, 56.
...Shaft, 57...Spring. 1 2

Claims (1)

[Claims] In a press device in which a flange portion of a plastic container body thermoformed by sheet forming is heated and pressed between a male press die and a female press die, the body and bottom portions of the container body are attached to the male press die. A press device characterized in that a guide having a corresponding shape is attached, and a press plate for pressing the bottom of the container body is elastically held inside the press female die.