JP2001191136A - Forming device foe elliptic tapered metallic can body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forming device for an elliptic tapered metallic can body whose plane is formed into an elliptic shape and whose front is formed into a tapered shape in one process, whose tapered surface in the curved surface is worked with high precision, whose design is excellent, whose productivity is excellent and whose manufacturing cost is reduced. SOLUTION: Die segments consisting of at least twelve pieces or more, which are movable in the radiating direction, are arrayed in an elliptic shape and have die parts inclined in accordance with tapered angles, are always and respectively moved in the reducing direction by elastic force of an elastic member. Respective die segments are moved in the expanding direction by an operating member against elastic force of the elastic member. The width of the die segment corresponding to the linear part is enlarged and also the width of the die segment corresponding to the curved part is set to be small using the boundary between the linear part and the curved part of the ellipse as a reference. A nearly cylindrical forming base stock in which both end parts of a metallic plate are joined is formed into the metallic can body whose plane is elliptic and whose front is composed of the tapered shape having the prescribed and inclined angle by respective segments moving in the expanding direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a device for forming an oblong tapered metal can body that forms a metal can body having a tapered front surface (in the present invention, a metal can body refers to a body portion before a bottom plate and a cover plate are attached).

[0002]

With the widespread use of the welding can method, cylindrical and rectangular metal cans have been widely used. However, these metal cans have a low accumulation efficiency during transportation and accumulation. In order to increase the height, facilitate disposal, and enhance design, the width of the front surface is formed in a tapered shape that gradually increases from below to above.

On the other hand, in order to increase the accommodation volume and enhance the design, a metal can body having an oblong flat surface has been used. In this kind of metal can body,
It was difficult to form the above-mentioned tapered shape for the following reasons.

That is, when the upper and lower parts of a can material welded in a long cylindrical shape having an inner diameter almost equal to the upper and lower parts are pulled by a force corresponding to the angle of the taper, the intermediate part is excessively elongated as compared with the end part. If the top and bottom widths are shortened or the upper and lower sides are stretched with different pulling forces, they are stretched in a fan shape and the height of the can is locally different, so that the can cannot be formed. .

[0005] This disadvantage can be solved to some extent by separately performing the processing of forming a linear portion into a tapered shape and the processing of forming a curved portion into a tapered shape in an oval shape. And the production cost increases.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned conventional drawbacks. An object of the present invention is to form a flat oblong surface and a tapered front surface in one step. An object of the present invention is to provide an apparatus for forming an elliptical tapered metal can body.

Another object of the present invention is to provide an apparatus for forming an elliptical tapered metal can having excellent machining precision of a tapered surface on a curved surface and excellent design.

Another object of the present invention is to provide an apparatus for forming an elliptical tapered metal can body which is excellent in mass productivity and can reduce the manufacturing cost.

[0009]

SUMMARY OF THE INVENTION The present invention is directed to a mold segment comprising at least 12 or more mold segments which are movable in a radial direction, are arranged in an oval shape, and have a mold portion inclined according to a taper angle. An elastic member that moves each mold segment in the reduction direction, and an actuating member that moves each mold segment in the enlargement direction against the elastic force of the elastic member, and based on the boundary between the straight line portion and the curved portion of the ellipse As the width of the mold segment corresponding to the straight part is increased and the width of the mold segment corresponding to the curved part is set to be small, the substantially cylindrical molding material in which both ends of the metal plate are joined is removed from each mold segment in the direction of enlargement. The plane is oblong due to the movement of
The front surface can be formed into a metal can body having a tapered shape having a predetermined inclination angle.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 is a partially cutaway front view showing the outline of a molding apparatus, FIG. 2 is a plan view of FIG. 1, FIG. 3 is an overall perspective view of an oblong tapered metal can body, and FIG. 4 is a central longitudinal sectional view of FIG. is there.

The table 3 of the forming apparatus 1 is formed with an opening 3a similar to an ellipse which is a plane shape of the metal can body 5 to be formed, and the table 3 around the opening 3a has a large number of mold supporting portions 3b. It is formed so as to extend in the radial direction at a required interval in the circumferential direction. The mold segments 7 are supported on the respective mold support portions 3b so as to be movable in the radial direction. Reference numeral 2 in the drawing is a cover attached to the upper surface of the table 3.

Each mold segment 7 has a guide portion 7a supported by a mold support portion 3b and a mold portion 7b having a mold surface formed on an outer surface.
The mold portion 7b is inclined and erected at an angle substantially corresponding to the taper of the metal can body 5. Also, among the mold segments 7 arranged in the circumferential direction, four mold segments 7 located at the boundary between the oval straight line portion and the curved portion in the metal can body 5 constitute a reference mold segment 7c. Each mold segment 7 extending from the reference mold segment 7c to a straight line portion
Has a large circumferential width, and each of the mold segments 7 from the reference mold segment 7c to the curved portion has a small circumferential width.

Each of the mold segments 7 has a length of at least 12 or more as a whole (an example using 16 mold segments is shown in the figure), and the length thereof matches the plane shape of the metal can body 5 to be formed. They are arranged in a circle and constitute a mold for the metal can 5. The number of the mold segments 7 may be increased in order to reduce the amount of stretching of the mold segments 7 with respect to the molding material 4 and achieve uniform molding by reducing the number of the mold segments 7. The durability of itself deteriorates. For this reason, the number of the mold segments 7 should be at least 12 or more, and 16 is a preferable example.

Incidentally, Mold part 7b in each mold segment 7
Is set slightly larger (1.02 to 1.06) with respect to the taper angle α of the metal can 5 in consideration of the elastic return of the metal can 5 after molding.

A locking portion 7d is formed on the upper portion of each mold segment 7, and a ring-shaped elastic member 9 is provided on the locking portion 7d.
Are locked respectively. The elastic member 9 moves the respective mold segments 7 in the reducing direction adjacent to each other by the elastic force. Further, a sliding contact portion with which a cam body 13 described below slides is provided on the inner surface of the base of each mold segment 7.

A moving member 15 constituting a part of an operating member such as a hydraulic cylinder having a vertical axis shown in the figure is provided on a main body frame (not shown) located below the opening 3a.
And a cam body 13 which constitutes a part of the operating member is attached to the operating shaft 15a of the moving member 15.
The cam body 13 has a plane substantially coincident with the plane of the metal can body 5,
It has an inclined cam surface that slides on the sliding contact portion of each mold segment 7 and moves each mold segment 7 in the radial direction (enlargement direction) as it moves upward.

The inclination angle of the inclined cam surface of the cam body 13 is set according to the amount of extension of the molding material 4. More specifically, the molding material 4 is stretched by about 5 to 10% to form a metal can body 5 having an oblong flat surface and a tapered front surface. The angle may be set.

The operation of forming the metal can 5 by the forming apparatus 1 having the above-described configuration will be described. 5 is a partially broken explanatory view showing a state before molding, FIG. 6 is a partially broken explanatory view showing a molded state, and FIG. 7 is a plan view showing states before and after molding.

First, the forming material 4 of the metal can body 5 is formed into a long cylindrical shape by welding both ends in the longitudinal direction of a rectangular metal plate. Then, the molding material 4 is moved to the center side by the elastic force of the elastic member 9 to set the molding material 4 on the outer peripheral side of each of the adjacent die segments 7, and then the moving member 15 is operated to move the cam body 13 upward. By sliding the inclined cam surface to the sliding contact portion, each mold segment 7 is moved in the enlargement direction, and the inner surface of the set molding material 4 is pressed to have a predetermined inclination angle β and an oval shape. The metal can 5 is formed by plastic deformation.

At the time of molding, since the circumferential width and the number of divided segments of each mold segment 7 are adjusted in accordance with the linear portion and the curved portion, the molding material 4 corresponding to each mold segment 7 is locally applied. The metal can body 5 having an oblong tapered shape can be formed by substantially uniform stretching by stretching. Particularly, in the curved portion, the number of divisions of the mold segment 7 is larger than that in the straight portion, and the width in the circumferential direction is set to be narrow. it can.

The specific amount of stretching of the molding material 4 is desirably about 5 to 10%, and the amount of movement of each mold segment 7 in the enlargement direction may be adjusted within this range.

After the molding operation, when the moving member 15 is moved backward to move the cam body 13 downward, each mold segment 7 is moved in the reducing direction by the elastic force of the elastic member 9, and the plane is formed into an elliptical shape. A metal can body 5 having a tapered front face
Is made removable. At this time, when each mold segment 7 is released from the inner surface of the formed metal can 5, the taper angle of the metal can 5 becomes slightly smaller than the inclination angle β of the mold portion 7 b in the mold segment 7 due to the internal stress. However, as described above, the inclination angle β of the mold portion 7b is
Slightly larger (about 1.0
2 to 1.06), the metal can 5 can be formed at a desired taper angle α. As described above, the metal can body 5 having an oblong flat surface and a tapered front surface is formed into a metal can by curling the periphery of the bottom plate fitted in the lower portion.

In the present embodiment, the molding material 4 is stretched by each of the divided mold segments 7 corresponding to the shape of the metal can body 5 to be molded, thereby avoiding an excessive tensile force from being deformed. The plane is an ellipse in one molding operation,
The front surface can be formed into a metal can body 5 having a tapered shape. In particular, in the curved surface portion of the metal can body 5, the number of divisions of the corresponding mold segment 7 is large, and the circumferential width is set to be narrow, so that the curved surface can be formed with high accuracy.

In the above description, each of the mold segments 7 has a structure in which the tip portion is inclined in the reduction direction with respect to the base end portion in the respective mold portions 7b. It is.

In the above description, the operating member for moving the mold segment 7 is constituted by the cam body and the moving member 15. As shown in FIG. 8, a cam shaft 81 is provided at the base end of each mold segment 7, and The cam shaft 81 is engaged with a cam hole 85 extending in a radial direction and a rotational direction provided in a cam disk 83 rotatably supported at a predetermined angle.
A structure may be used in which each mold segment 7 is moved in the enlargement direction and the reduction direction by the cam shaft 81 that slides in the cam hole 85 with the rotation of 3. In addition, each mold segment 7
Can be moved in the enlargement direction. In addition to the above-described structure using a cam and the structure using a disk, the opening 3a of the table 3 can be used.
The base end of each mold segment 7 is swingably supported on the periphery, and a link mechanism is connected to the base end of each mold segment 7 so that each mold segment 7 can swing in the enlargement direction and the contraction direction. Alternatively, a lever structure for forming the metal can body 5 into a desired shape may be used.

[0026]

According to the present invention, the flat surface can be formed in an oval shape and the front surface can be formed in a tapered shape in one step. In addition, the processing accuracy of the tapered surface in the curved surface is good, and the design is excellent. Furthermore, it is excellent in mass productivity and can reduce manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a partially broken front view schematically showing a molding apparatus.

FIG. 2 is a plan view of FIG.

FIG. 3 is an overall perspective view of an elliptical tapered metal can body.

FIG. 4 is a partially cutaway front view of FIG. 3;

FIG. 5 is a partially broken explanatory view showing a state before molding.

FIG. 6 is a partially broken explanatory view showing a molding state.

FIG. 7 is a plan view showing a state before and after molding.

FIG. 8 is a perspective view showing a modified embodiment.

[Explanation of symbols]

1-forming apparatus, 3-table, 5-metal can, 7-type segment, 9-elastic member, 13-cam member as operating member, 15-moving member

Claims (5)

[Claims] 1. A mold segment comprising at least 12 or more mold segments movable in a radial direction, arranged in an elliptical shape, and inclined according to a taper angle, and always moving each mold segment in a reduction direction. And an actuating member for moving each mold segment in the direction of enlargement against the elastic force of the elastic member, and a mold corresponding to the linear portion based on the boundary between the linear portion and the curved portion of the plane ellipse. The circumferential width of the segment is set to be wide and the circumferential width of the mold segment according to the curved portion is set to be narrow. An apparatus for forming an oblong tapered metal can body, which is capable of being formed into a metal can body having an oblong flat surface and a tapered front surface with a predetermined inclination angle by moving a mold segment. 2. An apparatus according to claim 1, wherein each of the die segments has a tip end portion inclined at a predetermined angle in a direction of enlargement with respect to a base end portion at a predetermined angle. 3. The molding apparatus according to claim 1, wherein each mold segment has a tip end portion inclined at a predetermined angle in a reducing direction with respect to a base end portion at a predetermined angle. 4. The apparatus according to claim 1, wherein the actuating member comprises a cam body having a cam surface that slides on each mold segment and moves in a direction of enlargement by a predetermined distance, and a moving member that moves the cam body. Molding device for circular tapered metal cans. 5. A cam disc according to claim 1, wherein said actuating member has a cam hole for engaging each mold segment and slidably supporting said mold segment, and a turning member for turning said cam disc at a predetermined angle. An apparatus for forming an elliptical tapered metal can body comprising: