JPH0244612B2 - HENKEIKANNOSEIHO - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing deformed cans. More specifically, the present invention relates to a method for deforming metal cans used for aerosol products and food packaging containers.

[Prior Art] Conventional aerosol cans have only been produced in cylindrical shapes due to long-standing legal restrictions and ease of production.

However, in the case of aerosol products for cosmetics, for example, it is desirable to improve the design by making various changes to the appearance, such as unifying the design with other containers such as glass containers.

Methods for deforming metal cans include, for example, adding various mechanisms and devices to the impact molding mold to form a deformed can at the time of impact molding, and the Basil molding method (using urethane rubber etc. inside the metal can). Possible methods include the magnetic wave forming method (a method in which a metal can is placed inside a split mold, a coil is inserted into the metal can, and the coil is expanded from the inside).

[Problems to be Solved by the Invention] All of the above-mentioned processing methods require expensive and complicated equipment, and there are problems in that the degree of deformation is small.

An object of the present invention is to provide a processing method that allows a metal can to be easily subjected to a relatively large deformation that provides a high design effect.

[Means for Solving the Problems] The method for manufacturing a deformed can of the present invention involves sequentially applying a netting process and a curling process to the vicinity of the opening of a bottomed cylindrical metal can, and then applying a netting process and a curling process to the vicinity of the shoulder of the metal can and A drawing process is applied to each outer periphery near the bottom, and a pressing process is applied to deform the metal can into an elliptical cross-section by pressing the body in the radial direction while supporting the area near the opening and the bottom of the metal can in the axial direction. This is a structural feature.

Note that curling in this specification refers to not only the case where the edge 2a of the opening 2 is completely rounded into a circular cross section as shown in FIG. This is a concept that also includes processing.

[Function] In the method for manufacturing a deformed can of the present invention, after the netting process, the edge of the opening is once curled. This increases the strength and rigidity of the can. Therefore, when drawing the side surface, there is no need to insert a pilot (3 in FIG. 1) into the interior of the metal can, unlike in normal necking processing. Furthermore, since the coating film on the inner or outer surface of the metal can is not pressed too hard by the pilot, the burden on the coating film is reduced.
In addition, by applying a drawing process to the outer periphery of the shoulders and bottom in advance, the rigidity of the can is increased and the body protrudes outward from other parts. Since the pressing process is performed by pressing in the same direction, the flattened curved surface is smooth and easy to mold.

Furthermore, when drawing the shoulder and bottom into a cylindrical shape and forming a tapered part that smoothly continues between that part and the body, the continuity of the curved surface in the final shape becomes smooth. There are advantages.

[Example] Next, the manufacturing method of the present invention will be explained with reference to the drawings.

FIG. 1 is a process explanatory drawing showing one embodiment of the manufacturing method of the present invention, and FIGS. 2 and 3 are sectional views of essential parts showing an embodiment of a metal can subjected to curling processing according to the present invention, respectively. 4 and 5 are process explanatory diagrams showing other embodiments of the drawing process in the manufacturing method of the present invention, respectively. FIG. 10 is a perspective view and a partially cutaway plan view showing an example of a deformed can manufactured by the manufacturing method of the present invention, and FIG. 11 and FIG.
FIG. 3 is a side view of the modified can shown in FIG.

FIG. 1 shows an embodiment of the method for manufacturing a deformed can according to the present invention, and shows an aluminum can 1 formed into a cylindrical shape with a bottom by a conventionally known impact extrusion process A.
The process is shown in the order of processing, from aluminum monoblock cans (so-called aluminum monoblock cans) to modified cans for aerosol products. The can 1 is first stocked with a pilot 3 inside the opening 2 in the necking process B.
is inserted, and the vicinity of the opening 2 is squeezed to a desired thickness using a mold 4, and at the same time a shoulder portion 5 is formed.
The width of the shoulder portion 5, that is, the difference in diameter between the original trunk portion 6 and neck portion 7, is selected depending on the degree of drawing processing D1, D2 and pressing processing E, which will be described later. Further, the necking process B can be performed by a press using a conventionally known mold, and if a wide shoulder part 5 is required, the necking process B is performed several times so that the diameter of the neck part 7 gradually becomes thinner. Repeated.

Next, the neck portion 7 is subjected to a curling process C. When manufacturing aerosol cans, the netting process C is usually performed so that the edge 2a of the opening 2 faces outward as shown in FIG.
It may be wrapped inside. Further, in the case of a metal can for food such as a youth can, a curling process C may be performed to form a flange portion 7a having a U-shaped cross section that opens outward, as shown in FIG. Further, after the curling process, processing such as making the curled portion flat may be performed.

The can 1 that has been subjected to the curling process C is further subjected to drawing processes D1 and D2 to narrow the outer peripheral portions of the shoulder portion 5 and the bottom portion 8.

The drawing processes D1 and D2 can be performed by a conventionally known method using, for example, drawing dies 10 and 11 and knockout plates 12 and 13.

In the manufacturing method of the present invention, the drawing process is performed only in the vicinity of the relatively rigid shoulder portion 5 and bottom portion 8, so there is no need to insert a member or the like into the can 1 to support the pressing force from the inside.

As a final step, the body 6 of the can 1 is subjected to a pressing process E in which it is pressed from two opposing directions (directions of arrow Q). The pressing process E is performed while supporting the opening 2 and the bottom 8, which have been subjected to the curling process C, in the axial direction (in the direction of arrow R) so that the can 1 does not stretch.

The can 1 subjected to the pressing process E becomes a deformed can 21 having an elliptical cross-sectional shape, as shown in FIGS. 9 to 12, for example.

In the manufacturing method of the present invention, before the pressing process E is applied, the shoulder portion 5 and the bottom portion 8 are subjected to drawing processes D1 and D2. Therefore, only the body, which protrudes outward and has relatively low rigidity compared to other parts, is pressed and deformed. Therefore, the pressing process is easy, and a smooth and accurate surface shape can be obtained even though no support member or the like is inserted inside the can 1.

In the drawing process D3 of the shoulder portion 5 shown in FIG.
4 and a smoothly continuous taper portion 15 are formed at the same time.

When forming such a tapered portion 15, the curved surface (for example, 16, 17 in FIG. 9) formed by the pressing process E and the narrowed portion 1
8 and 8 continue very smoothly.

Note that the same effect can be obtained even if the cylindrical portion 14 and the tapered portion 15 are formed near the bottom portion 8.

In the drawing process of the bottom part 8 shown in FIG. 5, a first drawing process D5 is performed in advance to form a gentle taper part 19, and then a first drawing process D5 is performed to form a cylindrical part 14 and a taper part 15 at the same time. A second drawing process D6 is performed.

When performing drawing in two steps like this,
The highly rigid bottom portion 8 can be processed relatively easily. In addition, in the first drawing process D5, when the bottom surface 20 is pressed in the direction of the arrow P with a mold or the like having an appropriate shape, the process can be performed more easily. Moreover, it has the advantage of being less prone to wrinkles and cracks.

Lubricating oil may be applied to the surface of the can 1 as necessary before or during the drawing process. This reduces the frictional force between the mold and the can surface, reducing processing pressure and protecting the printing etc. on the can surface. The lubricating oil is washed out after the final drawing or pressing process.

The pressing process E in the present invention is performed, for example, as follows.

First, the curling portion 24 and bottom portion 8 of the can 1 are held together using jigs 22 and 23 as shown in FIG.
In that case, the jigs 22, 23 are held so that the distance between them does not increase.

Next, the curved inner surface 2 as shown in Figure 8
The can 1 is pressed from both sides in the direction of the arrow Q using a set of metal molds 26 having a diameter of 5. As a result, the body 6 of the can 1 is deformed into an elliptical cross-section as shown by the two-dot chain line S in FIG.

The shapes of the jigs 22 and 23 may be such that they simply support the curling part 24 and the bottom part 8 from the outside as shown in FIG. 6, but, for example, as shown in FIG. It is preferable to include a jig 27 having a protrusion in contact with the bottom part 20 and a jig 28 in contact with the entire bottom part 20. This not only prevents the can 1 from stretching in the axial direction, but also prevents undesirable deformation (for example, distortion) in the vicinity of the opening 2 and the bottom 8.

By manufacturing in the above-mentioned method, for example, as shown in FIGS. 9 to 11, the shoulder portion 5 and the body portion 6 are directly and smoothly continuous on the pressed side surface 16, and the unpressed side surface 17 In this method, it is possible to obtain an elegantly deformed can 21 in which the shoulder portion 5, the constricted portion 18, and the body portion 6 are smoothly continuous with each other, and the side surfaces 16 and 17 and the body portion 6 and the bottom portion 8 are smoothly continuous. can. That is, the deformable can 21 manufactured by the manufacturing method of the present invention is integrally formed so that curved surfaces having different curvatures are smoothly continuous with each other. Therefore, the deformed can 21
It has high strength and pressure resistance, and can be suitably used as containers for aerosol products, for example.

The materials for the bottomed cylindrical metal cans processed by the manufacturing method of the present invention include, in addition to aluminum, copper, brass, iron, alloys based on these, and surface treatments (plating, plating, etc.) on these metals. Examples include various metals that can be plastically worked, such as those that have been subjected to oxide film forming, etc.

Although impact extrusion is preferred as a method for forming a bottomed cylindrical shape, other conventionally known methods such as deep drawing and spatula drawing may also be employed.

[Effects of the Invention] According to the method for manufacturing a deformed can of the present invention, a relatively large deformation can be easily applied to a metal can, thereby making it possible to easily manufacture a metal can with high design and practicality. can.

[Brief explanation of drawings]

FIG. 1 is a process explanatory drawing showing one embodiment of the manufacturing method of the present invention, and FIGS. 2 and 3 are sectional views of essential parts showing an embodiment of a metal can subjected to curling processing according to the present invention, respectively. 4 and 5 are process explanatory diagrams showing other embodiments of the drawing process in the manufacturing method of the present invention, respectively. FIG. 10 is a perspective view and a partially cutaway plan view showing an example of a deformed can manufactured by the manufacturing method of the present invention, and FIG. 11 and FIG.
FIG. 3 is a side view of the modified can shown in FIG. (Main symbols in the drawing), A: Impact extrusion processing,
B: Netsuking processing, C: Curling processing, D
1, D2: drawing process, 1: can, 2: opening, 5:
Shoulder, 6: Torso, 8: Bottom.

Claims (1)

[Scope of Claims] 1. A netting process and a curling process are performed in that order near the opening of a cylindrical metal can with a bottom, and then a drawing process is performed on the outer periphery of the metal can near the shoulder and near the bottom, A method for manufacturing a deformed can further includes performing a pressing process of deforming the metal can into an elliptical cross-section by radially pressing the body while supporting the metal can near the opening and bottom in the axial direction. 2 Claims in which the drawing process consists of a process of drawing the shoulder and bottom part into a cylindrical shape, and a process of drawing a part continuous to the part drawn into the cylindrical shape into a tapered shape so as to smoothly continue with the body part. The manufacturing method described in paragraph 1.