JPS62158539A - Curling method for tray container - Google Patents

Abstract

PURPOSE:To prevent buckling of a drooping flange part by pressing the drooping flange part against a side die by a vacuum suction, etc., and pressing a curling die against the drooping flange part. CONSTITUTION:Between an upper side 4 and a lower die 5, a horizontal flange part of a container body 1 is inserted and held, and also a side die 7 is provided a drooping flange part 2 from the outside. An intake hole 12 is provided on the side die 7, a diameter expanding part 13 is provided on the inside opening part, and also the outside opening part is connected to a vacuum pump. The vacuum pump is driven in advance, and the drooping flange part 2 is sucked to the external side in advance. Subsequently, in a state that the drooping flange part 2 has been made to adhere closely to the side die 7, a curling die 10 is pushed up toward the upper side 4, and an inward curl is formed in the end part of the flange part 2 by a curl forming part 11. According to this method, buckling to the inside of the drooping flange part 2 can be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for curling a tray container, and in particular,
The present invention relates to a method for curling a tray container in which an inward curl can be formed satisfactorily by bringing the peripheral flange portion of the tray container to be curled into pressure contact with a side die.

[Prior art and its problems]

Generally, containers such as aluminum trays are often curled around their peripheries. As shown in FIG. 5, this curling is generally an outer curl 3 in which the end of the hanging flange portion 2 forming the peripheral portion of the container body 1 is wound outward.

Further, this outer curl 3 is formed by a curling device as shown in FIG. That is, the horizontal flange portion 6 of the container body 1 is held between the upper mold 4 and the lower mold 5, and the side mold 7 is applied to the hanging flange portion 2 from the outside. The outer curl 3 is formed by pressing the curl forming part 8 provided at the end of the hanging flange part 2.

However, such an outer curl 3 is not only unfavorable in terms of appearance, but also increases the outer diameter, and may even cause injury at the tip end portion. Therefore, as a countermeasure against this problem, as shown in FIGS. 7 and 8, it is becoming increasingly common to form an inward curl 9 by winding the hanging flange portion 2 inward. This inward curl 9 is formed by a curling device as shown in FIG. That is, the horizontal flange portion 6 of the container body 1 is held between the upper mold 4 and the lower mold 5, and the side mold 7 is applied from the outside to the hanging flange portion 2, and then the side mold 7
Curling type along the inner wall of! 0 is pressed against the end side of the hanging flange portion 2. The above curling type lO
A curl forming part 11 is provided at the tip of the flange 2, and an inward curl 9 is formed at the end of the hanging flange part 2 along this curl forming part 11.

However, in such a conventional curling method, since the inside of the hanging flange part 2 of the tray container is not supported in any way, when the curling mold IO is pressed against the hanging flange part 2 side, the middle part of the hanging flange part 2 is It often happens that the inward curl 9 cannot be formed satisfactorily due to buckling inward.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for curling a tray container, which enables the formation of an inward curl in a good and reliable manner on the tray container.

[Means for solving problems]

In order to achieve the above object, the curling method of the present invention includes:
It is constructed by pressing the hanging flange part against the side die by vacuum suction force or elastic force of an elastic body during curling of the hanging flange part.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a curling device used in a first embodiment of the present invention, in which the same components as in the conventional device are denoted by the same symbols. As shown in the main entrance, the side mold 7 applied from the outside to the hanging flange portion 2 of the tray container has a suction hole 12.
is provided. This suction hole 12 is formed to pass through so as to communicate between the inside and outside of the side mold 7, and the inside opening is arranged so as to face the outer wall surface of the hanging flange portion 2.

Further, an enlarged diameter portion 13 is provided in the inner opening, so that the suction hole 12 faces over a wide range of the hanging flange portion 2.

Furthermore, a vacuum pump (not shown) is connected to the outer opening of the suction hole I2, so that suction force from the vacuum pump is applied to the suction hole 12.

In the curl forming method using such a curling device,
First, the vacuum pump is driven to suck the hanging flange portion 2 of the tray container outward through the suction hole 12.

Thereby, the hanging flange portion 2 is held in close contact with the side mold 7. Next, when the curling mold 10 is pushed up toward the upper mold 4 as shown by the arrow in FIG. The curl 9 is formed.

That is, the hanging flange portion 2 is curled while being drawn outward by the vacuum suction force, and a situation in which the hanging flange portion 2 is buckled inward is avoided.

In addition, as shown in FIG. 2b, when the white ginseng curl 9' is formed into a tight-fitting structure with no gaps, the close-fitting portion may be heat-sealed.

FIG. 3 shows a curling device used in a second embodiment of the present invention, in which the same components as in the curling device of the first embodiment are denoted by the same symbols. As shown in this figure, a plate-shaped elastic body 14 is provided at the pushing tip of the curling die 10.
is installed. This elastic body 14 is arranged on the side of the curl forming part 11, and before the curl forming, the elastic body 14 is arranged so as to be separated from the hanging flange part 2 for a predetermined period, and the elastic body 14 is placed on the side of the lower die 5. It extends upward along the outer surface, and its upper end is brought into contact with the tray container body 1.

In the curl forming method using the curling device having such a configuration, first, the curling mold 10 is pushed up toward the upper mold 4 as indicated by the arrow in FIG. As a result, the curl forming part 11 is pressed against the end of the hanging flange part 2 on the container side, and a white ginseng curl 9 as shown in FIG. It is pushed and bent so as to protrude outward (3l: dotted chain line), thereby being pressed onto the inner surface of the hanging flange portion 2 of the tray container. That is, the hanging flange part 2 is curled while being supported by the elastic body 14 from inside, and a situation where the hanging flange part 2 buckles inward is avoided.

FIG. 4 shows a curling device used in another embodiment of the present invention, and the same components as those in the first and second embodiments are given the same reference numerals and will be explained. The example uses the vacuum suction method of the first embodiment and the elastic force of the elastic body of the second embodiment, and the hanging flange part 2 is attached to the side mold 7.
The holding force that presses the parts together has been further improved, and the degree of prevention of inward buckling of the hanging flange portion 2 has been dramatically improved.

〔Effect of the invention〕

As described above, according to the method for curling a tray container according to the present invention, white ginseng curls can be formed extremely well on the hanging flange portion of the tray container without buckling the flange portion inward.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a half-box of a curling device used in a deaf patient according to the present invention, FIG. 2 is a vertical cross-sectional view showing an example of a container in which white ginseng curls are formed, and FIGS. 3 and 4 are a cross-sectional view of a curling device according to the present invention. FIGS. 5 and 6 are vertical sectional views of essential parts of a conventional tray container and curling device, and FIGS. 7 and 8 are respectively sectional views of other conventional examples. This is a vertical cross-sectional view of main parts showing a tray container and a curling device according to the above.
...Top mold 5...Bottom mold 7...Side mold
9,9'... White ginseng curl 10... Curling type II... Curl forming part 12... Suction hole 14... Elastic body Fig. 1 Fig. 2c! Figure 2b Figure 3 Figure 4 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] 1) By applying a side mold from the outside to the hanging flange provided at the peripheral edge of the container, and pushing up the curling mold so as to hit it from the end side of the hanging flange. In the tray container curling method in which an inward curl is formed on the hanging flange, the curling mold is suspended while the hanging flange is vacuum-adsorbed to the side mold so that the hanging flange does not buckle inward. A method for curling a tray container, characterized in that the tray container is pressed against a flange portion. 2) Apply a side mold from the outside to the hanging flange provided on the periphery of the container, and push the curling mold up so as to hit it from the end of the hanging flange, thereby forming an inner part of the hanging flange. In a method for curling a tray container to form a curl, the curling mold is pressed against the hanging flange while pressing the hanging flange against the side mold with an elastic body so that the hanging flange does not buckle inward. A method for curling a tray container, characterized in that: 3) Apply a side mold from the outside to the hanging flange provided on the peripheral edge of the container, and push the curling mold up so as to hit it from the end side of the hanging flange, thereby forming an inner part of the hanging flange. In a method for curling a tray container in which a curl is formed, the hanging flange is vacuum-adsorbed to a side die to prevent the hanging flange from buckling inward, and at the same time, the flange is held by an elastic body. A method for curling a tray container, characterized in that the curling die is pressed against a hanging flange.