JPS643580B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a processing device for processing the bottom wall of a small metal container for liquids having a capacity of, for example, about 1 to 3, and is particularly applicable to small aluminum beer barrels. It is intended for equipment for processing the bottom walls of suitable containers.

[Conventional technology]

Conventionally, some of these types of containers have protrusions for supporting legs formed at multiple locations on the bottom wall, but with the conventional processing method using an extrusion press, the strength of the protrusions for supporting legs is low and processing is labor-intensive. There's a problem.

An object of the present invention is to provide an apparatus for manufacturing containers that solves the above problems.

[Structure of the invention]

In the present invention, a shoulder portion whose outer surface is curved in a convex cross section is continuous to one end of the cylindrical body, and an outer peripheral edge of the center portion of the bottom wall is integrally continuous to the inner periphery of the shoulder portion. A plurality of protrusions for supporting legs protruding from the outer surface of the bottom wall are formed at intervals in the circumferential direction of the bottom wall on the inside of the shoulder in the radial direction. The object is a small metal container for liquids that is integrally formed at a location and has a crease with a recessed outer surface at the boundary between the shoulder and the outer peripheral edge of the center of the bottom wall.

According to the present invention, a device for processing the bottom wall of such a container has a metal cylindrical shape that fits into the inner periphery of the body of the material container, which is placed in an inverted position with the bottom wall being the top end of the container. A lower mold, a bed that fits inside the lower mold, an elastic body for molding the bottom wall of the container that is supported on the upper surface of the bed inside the lower mold, a lowered position where it comes into pressure contact with the outer surface of the bottom wall, and a raised position above it. a metal upper mold that can be raised and lowered between the upper mold and the upper mold; a lifting drive mechanism that supports the upper mold and moves it between the lowered position and the raised position; and a lower mold that moves the lower mold when the upper mold is in the lowered position. A lower die support mechanism is provided to support from below, and the upper die is provided with a concave shaped surface that presses against the outer surface of the bottom wall including the shoulder portion, and the outer surface of the supporting leg protrusion comes in pressure contact with the concave shaped surface. a concave surface is provided, and a curved surface is provided on the upper surface of the cylindrical lower mold to which the inner surface of the shoulder portion is pressed;
The elastic body is characterized in that a pressure contact surface is provided on the upper surface of the elastic body, with which the inner surface of the center portion of the bottom wall, including the inner surface of the support leg projection, comes into pressure contact.

〔Example〕

FIG. 1 is a schematic vertical cross-sectional view of a processing device according to the invention. In FIG. 1, a vertical cylindrical fixed bed 21 is provided on a foundation 20. A vertical cylindrical metal lower mold 22 is fitted around the bed 21 so as to be movable up and down. A dictation 23 (lower mold support mechanism) is provided below the lower mold 22.
The lower end is supported by a dictation 23 via four rods 25. The upper half of the lower mold 22 protrudes above the bed 21, and urethane 26 (an elastic body) is housed within the protruding upper half and is supported on the upper surface of the bed 21. A workpiece W (container material) is attached to the lower die 22 and the urethane 26 in a downward-opening position. Lower mold 22
The outer circumferential surface of is cylindrical, and the body portion 1 of the workpiece W is tightly fitted thereto. The bottom wall 3 of the workpiece W is partially spherical, and the upper surfaces of the urethane 26 and the lower die 22 are formed into a partially spherical convex shape so that the bottom wall 3 is in close contact with the bottom wall 3. Further, the urethane 26 and the bed 21 are provided with air vent holes 28 that open on the upper surface of the urethane 26.

An elevating ram 27 (upper mold elevating drive mechanism) is provided above the lower mold 22. A metal upper mold 29 is attached to the lower surface of the ram 27. The dimensions and shape of the molding surface 30 (lower surface) of the upper die 29 correspond to the dimensions and shape of the workpiece bottom wall 3 at the time of production, and the entire part is a partially spherical concave surface, and deep concave surfaces 31 are formed at multiple locations.
It is equipped with Around the upper die 29, the ram 2
The upper end of the vertical rod 32 is fixed to 7.
A work guide 33 is attached to the lower end of the rod 32.

The workpiece W is, for example, an aluminum plate having a thickness of 0.25 mm, which is formed into a bottomed cylindrical body by two-stage and three-stage drawing and trimming processing, and then
It is attached to the lower mold 22 as shown in FIG. When the mounting of the workpiece W is completed, the ram 27 descends and the workpiece W is
While holding the bottom wall 3 of the upper mold 29, the lower mold 22
and is pressed against the urethane 26 from above. By this pressure contact, the shoulder portion 2 of the workpiece bottom wall 3 is formed into a predetermined size and shape by being held between the upper surface of the lower mold 22 and the peripheral edge of the upper mold molding surface 30. Also, the urethane 26 is the upper mold 2.
9, an elastic repulsion force is applied from the entire upper surface of the urethane 26 to the bottom wall 3 of the workpiece W, and the center part of the bottom wall 30 (other than the shoulder part 2) also coincides with the upper molding surface 30. Molded into a partially spherical shape,
At the same time, a plurality of locations on the bottom wall 3 enter into the concave surface 31 to form supporting leg protrusions 9. After the protrusion 9 is formed by bulge processing in this way, the ram 27 and the upper die 29 rise, and the workpiece W is moved into the lower die 22.
removed from In this case, atmospheric pressure is introduced between the urethane 26 and the workpiece W through the air vent hole 28, so no negative pressure is generated between the two 26 and W, and the workpiece W after molding is not deformed. . The above-mentioned processing from drawing to bulge processing is performed in one step by a transfer press.

When the forming is completed, the work body 1 is removed as shown in Fig. 2.
A cap 15 or a lid is attached to the edge of the container by caulking or the like, and a container having a volume of, for example, 1.2 is completed. As shown in Fig. 3, which is a view in the - arrow direction of Fig. 2,
Six supporting leg projections 9 are provided at equal intervals in the circumferential direction of the bottom wall 3, and each protrudes in a hemispherical shape as shown in FIG. Therefore, even though the entire bottom wall 3 is a curved surface, the projections 9 allow the container to be stably placed on the base 12 such as a table.

Next, an example of specific dimensions and shapes of each part of the bottom wall will be explained with reference to FIGS. 4 and 5.

In FIG. 4, which is a vertical cross-sectional partial view, 0-0
is the vertical center of the container. The container body 1 has a substantially cylindrical shape, and its lower end is integrally continuous with the center portion 5 of the bottom wall 3 via a shoulder portion 2 having a small radius of curvature r. bottom wall 3
is formed into a flat partially spherical shape and bulges downward, and the radius of cross-sectional curvature R of the central portion 5 is set to be large. The outer peripheral edge 6 of the bottom wall central portion 5 has the above radius R.
It has a radius of cross-sectional curvature R' smaller than that of the shoulder part 2, and projects downward from the inner periphery of the shoulder part 2 in a stepped manner to provide a step S between the shoulder part 2 and the center part 5 of the bottom wall. The container wall thickness t is, for example, 0.2 mm, and the step S is 1.0 t to 2.0 t (0.2 to 0.4
mm). Reference numeral 7 denotes a boundary between the shoulder 2 and the edge 6, and when the container is viewed from the outside, the boundary 7 forms a concave fold and extends in a circular shape.

In FIG. 5, which is a view in the − arrow direction of FIG. 4,
As described above, a total of six protrusions 9 are provided at equal intervals in the circumferential direction of the bottom wall 3, and each protrusion 9 is formed into an elongated shape in the radial direction of the bottom wall 3. In FIG. 4, the bottom wall 3 of the peripheral bent part (foot) of the protrusion 9
The outermost end 10 in the radial direction of the boundary 7
Same as or slightly more than boundary 7 (1 to 2 mm)
It is located on the inside (right side in FIG. 4), and the innermost end 11 is located in the radial middle part of the bottom wall 3. When the protrusion 9 lands on the foundation 12 and supports the weight of the container or contents, the shape of the protrusion 9 is set so that the center of load (grounding point P) of the protrusion 9 with respect to the foundation 12 is located closer to the outer end 10. ing.

According to this structure, the shoulder portion 2 with a small radius r acts as an annular reinforcing portion on the bottom wall 3, and the protrusion 9 is located adjacent to the reinforcing portion, so that the strength of the area around the protrusion 9 can be increased. Therefore, buckling can be prevented from occurring in the area around the protrusion 9 even when the weight of the contents is added. Furthermore, since the protrusion 9 does not penetrate into the shoulder portion 2, the dimensions and shapes of the upper surface of the lower mold 22 and the molding surface 30 of the upper mold 29 in FIG. 1 can be simplified, and the manufacturing cost of the mold can be reduced.

Furthermore, as shown in Fig. 4, the outer peripheral edge 6 protrudes stepwise from the shoulder 2, and there is a step S between the shoulder 2 and the center part 5 of the bottom wall, so that there is a bend at the boundary 7 between the two. A mesh is formed and the boundary 7 also becomes a high-strength reinforcing portion. Therefore, buckling around the protrusion 9 can be more reliably prevented.

〔Effect of the invention〕

As explained above, the container manufactured by the processing apparatus according to the present invention is configured as follows. That is, the container has a shoulder 2 whose outer surface is curved in a convex shape connected to one end of the cylindrical body 1, and the shoulder 2
The outer peripheral edge part 6 of the bottom wall central part 5 is integrally continuous with the inner periphery of the bottom wall central part 5, and the bottom wall central part 5 is formed into a generally partially spherical shape with a convexly swollen outer surface, and a plurality of parts protruding from the outer surface of the bottom wall are formed. Support leg protrusions 9 are integrally formed at a plurality of locations spaced apart in the circumferential direction of the bottom wall 3 on the radially inner side of the shoulder 2, and are connected to the outer peripheral edge 6 of the shoulder 2 and the center portion 5 of the bottom wall. It has a structure in which a crease with a concave outer surface is formed at the boundary 7.

In this structure, the continuous shoulder portion 2 of the trunk portion 1 acts as an annular reinforcing portion for the bottom wall portion in which the support leg projection 9 is formed. Further, the crease (boundary 7) on the inner circumference of the shoulder portion 2 also acts as an annular reinforcing portion for the bottom wall portion where the support leg projection 9 is formed. Therefore, although the weight of the contents of the container is concentratedly applied to the protrusion 9,
Buckling around the protrusion 9 can be reliably prevented.

In the apparatus according to the present invention, a metal cylindrical lower mold 2 is fitted to the inner periphery of the body of the material container W in an inverted position.
2 is brought into pressure contact with the inner surface of the shoulder part 2, and the concave forming surface 30 of the metal upper mold is brought into pressure contact with the outer surface of the bottom wall 3 including the shoulder part 2, and the concave surface 31 provided on the concave forming surface 30 is pressed. The lower mold 2 is pressed against the outer surface of the supporting leg protrusion 9.
The upper surface of the elastic body 26 disposed inside the support leg 2 is brought into pressure contact with the inner surface of the bottom wall central portion 5 including the inner surface of the supporting leg projection 9.

In this way, in the device of the present invention, the supporting leg protrusion 9 can be formed by bulge processing, so that the thickness of each part of the protrusion 9 can be made uniform and the strength of the protrusion 9 itself can be increased. Since buckling of the protrusion 9 is prevented by the shoulder portion 2 and the crease (boundary 7), buckling and deformation of the protrusion 9 and its surroundings can be reliably prevented. Therefore, the thickness of the container can be reduced to, for example, 0.25 mm, reducing material costs and facilitating processing. Furthermore, the apparatus according to the present invention has the advantage that high-strength protrusions 9 can be easily formed.

Furthermore, according to the above structure, since the inner surface of the bottom wall inside the crease 7 is supported by the elastic body 26 during processing, when the inner surfaces of both the inner and outer portions of the crease 7 are supported by metal materials. Compared to this, it is possible to effectively prevent local stress and strain from concentrating when a crease is formed. Therefore, cracks or the like can be prevented from forming in the folds 7, and the strength thereof can be maintained sufficiently high, so that the above-mentioned reinforcing effect by the folds 7 can be reliably obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical cross-sectional view of a processing device according to the present invention, FIG. 2 is a schematic vertical cross-sectional view of a container processed using the device of the present invention, FIG. The figure is a partial schematic vertical cross-sectional view showing in detail the cross-sectional shape of a container processed using the apparatus of the present invention, and FIG. 5 is a view taken along the - arrow in FIG. 4. 1... Torso, 2... Shoulder, 3... Bottom wall, 5...
Bottom wall center, 6...outer periphery, 7...boundary, 9...
...Protrusion for supporting leg, 21...Bed, 22...Lower mold,
23... Diction (lower mold support mechanism), 26
... Urethane (elastic body), 27 ... Elevating ram (upper mold elevating drive mechanism), 29 ... Upper mold, 30 ... Molding surface, 31 ... Concave surface.

Claims (1)

[Claims] 1. A shoulder whose outer surface is curved in a convex cross section is connected to one end of the cylindrical body, and the outer peripheral edge of the center of the bottom wall is integrally connected to the inner periphery of the shoulder, and the center of the bottom wall is connected to the outer periphery of the shoulder. The outer surface is formed into a roughly partially spherical shape with a bulging shape, and a plurality of protrusions for supporting legs protruding from the outer surface of the bottom wall are integrated at multiple locations spaced apart in the circumferential direction of the bottom wall radially inside the shoulder. A device for processing the bottom wall of a small metal container for liquids, in which a crease is formed at the boundary between the shoulder and the outer peripheral edge of the center of the bottom wall, and the outer surface is recessed. A metal cylindrical lower mold that fits into the inner periphery of the body of the material container placed in an inverted position, a bed that fits inside the lower mold, and a container bottom that is supported by the top surface of the bed inside the lower mold. An elastic body for wall forming, a metal upper mold that can be raised and lowered between a lowered position in pressure contact with the outer surface of the bottom wall and a raised position above it, and a metal upper mold that supports the upper mold and moves between the lowered position and the raised position. and a lower mold support mechanism that supports the lower mold from below when the upper mold is in the lowered position, and presses the upper mold against the outer surface of the bottom wall including the shoulder. a concave shaped surface is formed, a concave surface is provided on the concave shaped surface to which the outer surface of the supporting leg projection is pressed; a curved surface is provided on the upper surface of the cylindrical lower mold to which the inner surface of the shoulder portion is pressed; A device for processing a bottom wall of a small metal container for liquids, characterized in that a pressure contact surface is provided on the top surface of the container, with which the inner surface of the center portion of the bottom wall, including the inner surface of the supporting leg projection, comes into pressure contact.