JPS6123054B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing round metal cans, and more particularly, to a method for manufacturing round metal cans, particularly for filling positive internal pressure liquids such as carbonated drinks, etc.
The present invention relates to a method of manufacturing a round metal can having a thin body with a relatively small mouth suitable for sealing.

As a method for manufacturing pressure-resistant metal round cans suitable for filling and sealing carbonated beverages, etc., recently published in Japanese Patent Application Laid-Open No. 54-49611, etc., one of the open ends of two thin-walled cylindrical cups with a bottom is connected to the other. A method has been proposed in which a hot-melt type adhesive is inserted and fitted into the inside, and the material is integrally joined. In this case, it is necessary to pressurize and rapidly cool the molten adhesive layer in order to achieve an airtight bond without causing pinholes or the like. However, if the diameter of the mouth is much smaller than the diameter of the body, it is difficult to insert an appropriate pressure receiving body inside the can, and the body is thin and the insertion part is also flexible. However, there was a problem in that it was difficult to pressurize and rapidly cool the adhesive layer at the insertion part, and therefore it was difficult to obtain an airtight joint.

The present invention aims to solve the problems of the prior art as described above.

To achieve the above object, the present invention comprises a one-piece upper can body having a thin-walled body and a mouth portion with a smaller diameter than the body, and a one-piece lower can body having a bottom and a thin-walled body. Either the open end of the body of the upper can body or the open end of the body of the lower can body is fitted into the inside of the other to form a fitting part, and in the fitting part, the open ends meet each other. A method for producing a metal round can that is bonded via a heat-sealable adhesive layer, the fitting portion being heated to melt the adhesive layer inserted into the fitting portion, and the main shaft and the An internal pressing member having a cooling roller provided at the tip of a singing body swingably attached to the main shaft is inserted through the opening so that the axis of the main shaft and the axis of the body coincide, and the singing body is swingably attached to the main shaft. (1) The cooling roller swings the moving body until the cooling roller comes into contact with the inner surface of the fitting part, and rotates around the main axis as the main shaft rotates, and at the same time contacts the inner surface of the fitting part and rotates. The main shaft is rotated by an external annular member in contact with the outer surface of the fitted part (2) or an external roller that is rotatable in contact with the outer surface of the fitted part while facing the cooling roller, and the adhesive layer is removed. The present invention provides a method for manufacturing round metal cans, which is characterized by pressing and quenching at the same time.

The present invention will be described below with reference to the drawings.

In FIGS. 1, 2, and 3, 1 is a round metal can, and the round metal can 1 in FIG. 1 has an adhesive layer 2 heated and melted by a high-frequency induction heating coil 3. The metal round can 1 shown in Figures 2 and 3
1 shows a state in which the adhesive layer 2 is attached to the inner pressing member 4 and is being pressed and cooled by the cooled roller 5 and the outer annular member 6.

The round metal can 1 consists of a thin (usually about 0.08 to 0.2 mm) cylindrical body 7, a shoulder 8, and a mouth 9 with a smaller diameter than the body 7, such as an aluminum (alloy) plate or a low carbon steel plate. It consists of a one-piece upper can body 10 integrally formed by deep drawing or drawing-ironing of a metal plate, and a thin body part 12 having the same diameter as the bottom part 11 and body part 7, which are also integrally molded from a metal plate. One-piece lower can body 13
It's getting more familiar. The open end 12a of the body 12 of the lower can body 13 is reduced in diameter by the thickness of the adhesive layer 2, and the open end 12a is glued into the open end 7a of the body 7 of the upper can body 10. It is fitted through the agent layer 2, and a fitting part 14 is formed. Adhesive layer 2
The insertion is carried out, for example, by heat-sealing and solidifying a heat-fusible film around the outer periphery of the open end 12a, and then fitting the open end 12a into the open end 7a. Alternatively, after pasting a heat-fusible adhesive layer on the inner periphery of the open end 7a, the open end 1 with or without an adhesive layer on the outer periphery
2a may be fitted into the open end 7a. In the example shown in FIGS. 1 to 3, the open end 12a of the lower can body 13
is fitted into the open end 7a of the upper can body 10; however, the open end 7a may be fitted into the open end 12a. Also, the open end 12
a does not necessarily have to be reduced in diameter (in this case, the diameter of the body 12 is smaller than the diameter of the body 7 by twice the thickness of the adhesive layer 2). Alternatively, the open end portion 7a may be expanded in diameter by the thickness of the adhesive layer 2. Further, the insertion portion 14 may be located below the round metal can 1, as shown in FIG. 5 or FIG. 8, for example, or may be located above it. The present invention is not limited to these aspects of the fitting portion 14.

A curled portion 9a for fitting a cap (not shown) is formed on the periphery of the mouth portion 9. Since the mouth part 9 has a much smaller diameter than the body part 7, compared to the case where the double-sealing method of the lid part is adopted with a known metal or plastic cap,
It can be more easily hermetically sealed and opened. The bottom part 11 is slightly thicker than the body part 12, and in order to maintain pressure resistance, it protrudes outward in a dome shape, and to ensure upright stability, as shown in FIG. (6 in the figure)
A small convex portion 15 is formed. The present invention is not limited by the shape of the bottom part 11, and for example, as shown in FIGS.
It may be 1'. In this case, in order to ensure upright stability, it is preferable to fit a ring 16 (made of plastic, for example) having an annular convex portion 16a to the bottom portion 11' and the lower part of the body portion 12, for example. Further, although not shown, the bottom portion 11 may have a dome shape that protrudes inward. As shown in FIG. 1, the bottom part 11 and the lower part of the body part 12 are fitted into the recess 17a of the support body 17, and the small protrusion 15 is engaged with the recess 17a, so that the rotation of the internal pressing member 4 is prevented. The body 12 is designed not to rotate. The support body 17 is connected to the through hole 18 of the fixed plate 18.
It is possible to slide vertically within a.

The internal pressing member 4 includes a main shaft 19, a swinging body 20 swingably attached to the lower end of the main shaft 19, and a swinging body 2
The movable shaft 21 is movable in the axial direction of the main shaft 19 for swinging the main shaft 19, and a link 22 is provided. As shown in FIG. 1, the internal pressing member 4 raises the movable shaft 21 so that the singing body 20
The dimensions are such that it can pass through the mouth portion 9 in a state substantially parallel to. As shown in FIG. 2, the rocking body 20 includes a rocking shaft 23 that is pivotally supported by the lower end of the main shaft 19 and can be rocked by a movable shaft 21 via a ring 22, and a rocking shaft 23 that slides along the rocking shaft 23. A movable roller support 24, a roller 5 whose axis is parallel to the axes of the trunks 7 and 12, which is supported at the tip of the roller support 24, and a swing shaft 23 and the roller support 24.
The spring installed between the
26, and when the movable shaft 21 is lowered, the swinging body 20 is positioned almost at right angles to the main shaft 19, and the axis of the main shaft 9 and the metal round can 1 are aligned, and by the action of the spring 26, The dimensions are determined so that the roller 5 can press the inner surface of the insertion part 14. Further, a guide hole 27 is provided in the vicinity of the roller 5 of the roller support body 24 for the passage of a cooling medium (for example, -30°C brine) for cooling the roller 5, and the guide hole 27 communicates with a flexible tube 28. The flexible tube 28 further communicates with a guide hole 29 in the main shaft 19. A pawl 30 provided at the lower end of the main shaft 19 is provided to prevent the rocking body 20 from tilting further downward than the approximately horizontal position shown in FIG.

A flange portion 31 is fixed to the upper end of the main shaft 19, and the flange portion 31 is rotatably supported on a fixed plate 32 by a ball bearing 33. The main shaft 19 is rotated via a gear 35 by a gear 34 rotated by a drive device (not shown).
On the other hand, the guide hole 29 communicates with a planar hole 36 provided in the flange portion 31, and the planar hole 36 is connected to a fixed annular body 37 with which the side peripheral surface of the flange portion 31 is slidably in fluid-tight contact.
The cooling medium is connected to a guide hole 38 provided in the guide hole 38, and the cooling medium is supplied and discharged through the guide hole 38. The upper end 21a of the movable shaft 21 is rotatably connected to a joint 39 while being pressed by the joint 39, and the joint 39 can be moved up and down by an air cylinder (not shown) via a piston shaft 40.

The outer annular member 6 is made up of two split molds 6a each having a semicircular cross-section and whose inner diameter is equal to the outer diameter of the open end 7a of the body 7. It is movable in the radial direction through. The split mold 6a is provided with a guide hole 43 through which a cooling medium flows, and the cooling medium is supplied and discharged through a conduit 44.

``With the above-described apparatus, the adhesive layer 2 is melted, pressed, and rapidly cooled in the following manner.

First, as shown in FIG.
The movable shaft 21 rises, and the oscillator 20 moves to the main shaft 19.
With the outer annular member 6 open, the support 17 is raised and the round metal can 1 is
is raised, and when the insertion part 14 reaches a position facing the high-frequency induction heating coil 3 surrounding the insertion part 14, the support body 17 is stopped. At this point, the internal pressing member 4 is inserted into the round metal can 1 from the mouth part 9,
And their axes coincide. Coil 3 immediately
When electricity is applied, the open ends 7a and 12a are heated, and the polyamide resin (for example, nylon 11 or 1
2) The adhesive layer 2 made of a heat-fusible resin such as polyester resin is melted. Immediately, the coil 3 is deenergized, and at the same time, as shown in FIG. The movable shaft 21 is lowered to make the rocking body 20 horizontal, and the roller 5 is brought into contact with the inner surface of the insertion part 14, and the insertion part 14 is cooled by the action of the spring 26, and the roller 5 and the cooled outer annular member 6 are cooled.
The main shaft 19 is rotated while being pressed between the two (FIGS. 2 and 3). Therefore, the adhesive layer 2 is pressed one after another by the roller 5 that rotates on its own axis at the same time as it revolves, and voids such as pinholes are removed, and at the same time, it is rapidly cooled and solidified below its melting point, so that the open end 12a
A sound adhesive layer 2 is obtained that is in close contact with the outer surface of the wafer and the inner surface of the open end 7a. If a primer coating film such as a phenol epoxy paint is previously formed on the outer and inner surfaces, strong adhesive strength that can withstand high internal pressure can be ensured.

FIG. 7 shows a roller 5 instead of the outer annular member 6.
This is a drawing for showing an embodiment in which the adhesive layer 2 is pressed and rapidly cooled using an external roller 45 that is rotatable in contact with the outer surface of the insertion part 14 (that is, the outer surface of the open end 7a) while facing the . The external roller 45 is mounted on a vertical shaft 46 that hangs down from the flange portion 31 fixed to the main shaft 15, and is cooled by a cooling medium circulating in the guide hole 47. The other points are the same as those shown in FIGS. 1 to 3.

The inner surfaces of the upper can body 10 and the lower can body 13 are usually coated with a corrosion-resistant coating (not shown);
Since the metal at a' (see FIG. 1) is exposed, there is a risk that it will be corroded by the content liquid and metal ions will be eluted into the content liquid.

FIG. 8 shows an example of a coating device 48 for coating the end face 12a' of the round metal can 1 formed as described above with paint to prevent the above-mentioned defects. The coating device 48 has a main shaft 49 having the same structure and function as the husband of the internal pressing member 4, a swinging body 50,
It includes a movable shaft 51, a link 52, a swing shaft 53, a roll support 54, a spring 56, and a pawl 60.
However, the pressing force of the spring 56 is set to be relatively weak. The coating roller 55 is pivotally supported by the tip of the roll support 54, and is configured such that the lower surface of the flange 55a substantially contacts the end surface 12a'. A guide hole 57 and a flexible tube (one) 5 are provided on the lower surface of the flange portion 55a.
8. Through the guide hole (one) 59 penetrating the main shaft 49, paint is supplied (for example, by injection) in the same manner as in the case of the cooling medium described above. However, in this case, unlike in the case of a cooling medium, the paint does not circulate.
60 rotates the main shaft 49 to rotate the end face 12.
The coating film formed on a′ is shown.

According to the invention, pressing the molten adhesive layer;
Cooling is carried out by rotating the cooling roller inside the can, which is pivotally supported by the tip of the oscillator, and by the external annular pressing member or external roller, making it possible to form a sound bond without pinholes. have an effect. Furthermore, since the rocking body is swingably attached to the main shaft, it has the advantage that it can be easily moved into and out of the can body through the narrow mouth.

[Brief explanation of the drawing]

1 and 2 are partially cutaway front views of an example of an apparatus used for carrying out the present invention, in which FIG. 1 shows a state in which the insertion part is heated, and FIG. Figure 3 is a cross-sectional view taken along the - line in Figure 2; Figure 4 is a bottom view of the lower can body shown in Figure 1; Figure 5 is a metal A vertical cross-sectional view of the main part to show another example of the bottom of the lower can body of a round can, FIG. 6 is a bottom view of the metal round can of FIG. 5,
FIG. 7 is a partially cutaway front view of another example of the apparatus used for carrying out the present invention, and FIG. 8 shows the end surface of the open end of the lower body of a round metal can manufactured by the method of the present invention. FIG. 2 is a front view of main parts of an example of a painting device. DESCRIPTION OF SYMBOLS 1... Metal round can, 2... Adhesive layer, 4... Internal pressing member, 5... (cooling) roller, 6... External annular member, 7... Body, 7a... Open end, 9 ……
Mouth, 10... Upper can body, 12... Body, 12a
... open end, 13 ... lower can body, 14 ... fitting part, 19 ... main shaft, 20 ... rocking body, 45 ... external roller.

Claims (1)

[Scope of Claims] 1. A one-piece upper can body having a thin-walled body and a mouth portion smaller in diameter than the body, and a one-piece lower can body having a bottom and a thin-walled body, the upper can Either the open end of the barrel of the body or the open end of the barrel of the lower can is fitted into the inside of the other to form a fitting part, and in the fitting part, the open ends are heat-sealed to each other. A method for manufacturing a metal round can that is bonded via a magnetic adhesive layer, the fitting portion being heated to melt the adhesive layer inserted in the fitting portion, and the main shaft being oscillated between the main shaft and the main shaft. An internal pressing member having a cooling roller provided at the tip of a movably attached rocking body is inserted through the opening so that the axis of the main shaft and the axis of the body coincide, and the rocking body is moved into the body. The cooling roller swings until it contacts the inner surface of the fitting part, revolves around the main axis as the main shaft rotates, and simultaneously rotates while contacting the inner surface of the fitting part, and the outer surface of the fitting part. A method for producing a round metal can, characterized in that the main shaft is rotated by an external annular member in contact with the adhesive layer to simultaneously press the adhesive layer and rapidly cool the adhesive layer. 2 Consisting of a one-piece upper can body having a thin-walled body and a mouth portion smaller in diameter than the body, and a one-piece lower can body having a bottom and a thin-walled body, the body of the upper can being opened. Either the end portion or the open end portion of the body of the lower can body is fitted into the inside of the other to form a fitting portion, and in the fitting portion, the open ends are coated with a heat-fusible adhesive layer. A method for manufacturing a metal round can that is attached to a main shaft and a metal round can that is attached to the main shaft so as to be able to swing. An internal pressing member having a cooling roller provided at the tip of the oscillating body is inserted through the opening so that the axis of the main shaft and the axis of the body coincide, and the oscillating body is held in place by the cooling roller in the insertion part. the cooling roller that swings until it contacts the inner surface, revolves around the main shaft as the main shaft rotates, and simultaneously rotates in contact with the inner surface of the fitting part; and the outer surface of the fitting part while facing the cooling roller. A method for producing a round metal can, characterized in that the main shaft is rotated by an external roller that is rotatable in contact with the adhesive layer to press the adhesive layer and simultaneously rapidly cool the adhesive layer.