[0001] The object of the present invention is to provide a can model for processed foods
or not, for use by food companies or others. Said model has an enhanced construction
in order to improve its use and efficiency over existing similar ones.
State of the Art
[0002] Cans for foods and other uses comprising three pieces with welded cylindrical bodies,
seamed by a mechanical process at their upper ends by a top and at their lower ends
by a bottom of same shape, are already known in the state of the art. Said cans may
or may not be provided with rims in the cylindrical body to reinforce it, allowing
the use of thin sheets.
[0003] There are two basic types for these cans:
- Three-piece cans with top and bottom of same diameter - These can are made of welded
cylindrical bodies (tubes), which are calendered and welded into the final diameter
of the can, then receiving conventional processes of flap formation, beading and closing
the top or bottom according to clients' requirements. One example of this kind of
can may be seen in Figure 1 of the state of the art.
- Three-piece cans with bigger top and smaller bottom in diameter - These are made of
welded cylindrical bodies (tubes), calendered and welded in the final diameter of
the can, with an additional process of diameter reduction on one of the ends of the
tube (necking), then followed by conventional processes of flap formation, beading
and closing the smaller diameter bottom, allowing to pile up filled cans by the difference
between top and bottom diameters. One example of this kind of can may be seen in Figure
2 of the state of the art.
[0004] With the advent of sterilization in continuous rotating autoclave (cooker cooler),
the two kinds of cans mentioned above have shown some unsurmountable inconveniences
for their processing:
- Three-piece cans with top and bottom of same diameter - In this case, the rolling
process of cans used in the continuous rotating autoclave is easily performed, and
the body of the cans (tube) may be previously printed, with no loss in print quality
after the rolling process. However, this solution harms the correct stacking, since
the cans do not fit the others.
- Three-piece cans with larger top and smaller bottom in diameter with diameter reduction
at one of the ends of the tube (necking)-These cans have the advantage of being easily
piled up. The neck-in is made on the can by the hanging of one of the ends of the
can whose single objective is to improve stacking. To prevent the can from rolling
around its own axis due to the big difference between the top and the bottom of the
can, an additional rim (reinforcement) on the body near the smaller bottom is required,
so that the friction during the process may allow the can to be rolled in the continuous
sterilization system without damaging the body of the can. In this case, excessive
friction damages the artwork, varnish and/or tin from the body of the can at that
reinforcement point. Due to this problem, the can is only labeled later on, creating
additional processing steps and lowering process speed. Furthermore, due to its smaller
diameter top, this kind of can is more difficult to open with conventional can openers
because of the neck formed in the cylindrical body at that point to fasten the smaller
top, which makes the correct placement of the opener more difficult.
Object of the Invention
[0005] Bearing the above in mind and in order to overcome the mentioned problems, the present
invention has been developed. It consists of a three-piece can, with cylindrical shape
with top and bottom of different diameters, wherein one of the ends goes through an
expansion process (increase in diameter or neck-out), but within certain limits not
to compromise its rolling on flat guides and surfaces minimizing friction of the external
part of the cylindrical body with finish or artwork while rolling. Said can may also
be piled up, since it is provided with top and bottom of different diameters which
fit in when stacked.
[0006] This form of embodiment of the can solves the presented inconveniences, since the
expanded cylindrical shape of the assembly allows for appropriate flexibility during
the use, meeting various forms of use of stackable cans with the artwork already printed
on the cylindrical body, especially in automatic thermal processing equipment of continous
rotating type (cooker cooler) wherein rolling of the can is required. The proposed
model also has the advantage of allowing the final user to open the can at any of
its end with a conventional can opener, usually at the cleanest end due to the piling
up.
Description of the Drawings
[0007] To better visualize the present invention, the attached figures are presented as
mere examples, not limiting the present invention, wherein:
- Figure 1 is a partial cross section view of a conventional three-piece can with top
and bottom of same diameter;
- Figure 2 is a partial cross section view of a conventional three-piece can with top
and bottom of different diameters, with reduced diameter at one of the ends of the
tube (necking);
- Figure 3 is a partial cross section view of a can according to the present invention;
- Figure 4 is a view of a stack of cans of the present invention;
- Figure 5 is a detailed view of a can rolling over a flat surface, showing the lack
of contact between the body of the can (tube) and the surface due to the existence
of a gap.
Preferred Embodiment of the Invention
[0008] The object of the present invention will be disclosed based on the above listed figures
given as examples, but not limiting the scope of protection of the present invention,
wherein the final can will be generically indicated as L.
[0009] The object of the present application consists of a can L, made of a welded body
(1), which is initially cylindrical and which afterward has one of its edges expanded
(neck-out), being said body (1) provided or not with reinforcement rims in its body
(2) when the metal sheet to form the body (1) is thin.
[0010] The can L is preferably made of tinplate and/or chrome- plated steel, appropriately
varnished and printed with the artwork defined by the user. The cylindrical body 1
is formed by the conventional process of plate cutting, formation of the body, calendering
and welding. Initially, the body (1) is built with the base dimension (smaller), the
tube is expanded in a conical shape forming the flange (flap) and subsequently the
rims for radial reinforcement of the can (2).
[0011] Said can L has an upper closing consisting of a conventional or easy-to-open top
(3) and a conventional or easy-to-open bottom (4). Said top (3) or bottom (4) is seamed
at one of the ends according to the needs of the user. When seamed, said top (3) and
bottom (4) form an upper (5) and lower (6) end that support the body of the can when
it is rolled.
[0012] Said ends (3, 4) have different diameters, being that the difference between them
should be comprised within a range between 2 and 6 mm. Said difference between diameters
defines a range A, which as a function of the height C of the can L will provide an
angle θ. Said angle θ should be within the range from 0.5 to 2° for the can to roll
without rotating around its own axis.
[0013] As an example, the table below shows the ratio between the diameter of the top (3),
bottom (4), height C and angle θ in relation to market conventional sizes:
Top (3) |
Bottom (4) |
Height (C) |
Angle θ |
73 |
70 |
83 |
1,035 |
73 |
70 |
92 |
0,934 |
73 |
70 |
95 |
0,905 |
99 |
96 |
118 |
0,728 |
127 |
124 |
135 |
0,637 |
155 |
152 |
152 |
0,565 |
155 |
152 |
178 |
0,483 |
155 |
152 |
226 |
0,380 |
[0014] The conical can is sent to the user with one of the ends (larger or smaller) already
seamed according to the client's requirements and/or tooling in the client's plant
to close the cans after product filling.
[0015] If the user makes use of continuous rotating equipment (cooker cooler), the roling
of the can L without harm to its body (1) is guaranteed by the support given by the
upper (5) and lower (6) edges, which create a gap as shown in Figure 5.
[0016] The present invention presents several advantages to the conventional models, such
as the cans may be processed in continuous rotating autoclave systems (cooker cooler
systems), the cans may be stacked, and, since the cans are expanded cans, less steel
is used in their manufacture, thus lowering manufacturing costs and sale price of
the metal container.
[0017] In addition, the user will not need tooling adaptations, since the closing process
is conventional and the tops and bottoms used are those already abundant on the market.
[0018] The proposed conical can, with said construction, may be made in diverse sizes and
capacities to meet different needs of users of this kind of packaging.
1. Improvement in three-piece can, being said can L comprised of a cylindrical body (1)
with rims (2), top (3) and bottom (4) characterized by the fact that said welded cylindrical body (1) is expanded into a conical shape (1),
provided with a top (3) of smaller diameter and of conventional or easy-open type
and a bottom (4) of bigger diameter, with conventional or easy-to-open type, having
said top (3) and bottom (4) diameter differences ranging from 2 to 4 mm, forming an
angle on the wall of the expanded body (1) from 0.1 to 2°, and that said top (3) and
bottom (4), when seamed, create support edges (5, 6) for the can L to be rolled on
flat surfaces.