IT201800004841A1 - METAL CONTAINER WITH VARIABLE RESISTANCE LID FOR EASY OPENING. - Google Patents

Description

METALLIC CONTAINER WITH RESISTANCE LID

VARIABLE FOR EASY OPENING

The present invention refers to a metal container with variable resistance lid for easy opening.

It is known to make metal containers, such as aluminum or tinplate food cans, equipped with a lid crimped to the container body and equipped with a perimeter pre-cut near the crimp. The lid includes a pull tab provided at one end with a ring portion, which the user grasps, and at the opposite end of a pressure peak, as well as a rivet for joining the lid between the two ends.

The initial opening phase takes place by acting on the traction tab in order to use the rivet as a rotation pin to cause the tab to lift from the top of the lid and the simultaneous breakage of the precut due to the pressure apex acting in the vicinity of the same. The opening continues by exerting a traction action on the lid by means of the ring portion according to a line of force that extends into the space above the container according to an arc of a circle and then continues substantially parallel to the plane of the container.

This operation requires the user to exert considerable force both in the initial stages of opening and in the subsequent stage.

Furthermore, the tendency of the lid to deformation in the direction transverse to the direction of traction during the opening phases with a strong elastic component makes it more difficult to exercise the traction action parallel to the plane of the container in the final stages of opening.

The user also risks injuring himself with the sharp edge of the portion of the lid already separated from the container body which tends to come closer to his hand due to a "rolling" of the lid in a direction transverse to the direction of traction.

Especially in the case of containers containing liquids and filled to the brim, such as fish products when packaged by filling with oil or brine, in the above described opening operations there is a high risk of spilling over the edge or in any case of spraying. by moving the lid some of the filling liquid.

Known lids generally have on their plane shapes distributed on the surface to obtain a certain degree of stiffening. This stiffening satisfies the stability requirements of the container, for example during the autoclave sterilization process for food containers or during preservation, or storage, before consumption.

However, these shapes are not suitable for preventing the lid from bending transversely to the direction of traction when opening the lid, nor above all solve the difficulties of traction during opening.

The purpose of the present invention is to create a metal container with a variable resistance lid for easy opening that solves the drawbacks of the aforementioned prior art.

Another purpose of the present invention is to make a metal container with a variable resistance lid for easy opening that requires a reduced use of traction forces compared to known lids, with the same geometry of the container.

Another purpose of the present invention is to make a metal container with a variable resistance lid for easy and particularly simple and functional opening, with low costs.

These purposes according to the present invention are achieved by making a metal container with variable resistance lid for easy opening as set forth in claim 1.

Further characteristics are provided in the dependent claims.

The characteristics and advantages of a metal container with variable resistance lid for easy opening according to the present invention will be more evident from the following description, exemplary and not limiting, referring to the attached schematic drawings in which:

Figure 1A is a plan view of a first embodiment of a metal container with variable resistance lid for easy opening object of the present invention;

Figure 1B is a section of the container of Figure 1 according to the line IB-IB;

Figure 2 is a plan view of a simplified version of the container of Figure 1;

Figures 3 to 6 show further embodiments of the container according to the invention provided with a simple shield and with coincident traction and opening lines;

Figures 7 to 9 show further embodiments of the container according to the invention provided with a complex shield and with coincident traction and opening lines;

figure 10 shows an embodiment bearing two simple shields placed in longitudinal sequence;

Figures 11 and 12 show two embodiments of the container according to the invention respectively provided with a simple or complex shield and with a non-coincident traction and opening line;

Figure 13 shows a further embodiment of the container according to the invention having a convex shield extended to the portion bearing the tab;

figures 14 and 15A and 15B show examples of shields progressively degrading until their height is canceled;

Figures 16 and 17 show two further embodiments of a container according to the invention in which the loading line is located near the rivet of the tab;

Figures 18A and 18B show an embodiment in which, by way of example, a perimeter concavity around the shield is shown;

Figures 19A to 19C show the opening sequence of the container of Figure 1.

With reference to the figures, a metal container with variable resistance lid for facilitated opening indicated as a whole is shown. The container 10 comprises a container body 12 and a lid 20, integral with the container body 12 along a perimeter edge 13.

In the example shown in the figures, the lid 20 is integral with the container body 12 along the edge 13 by seaming.

The lid 20 is equipped with a perimeter pre-cut 21 adjacent to the edge 13 for opening by means of a traction tab 14, joined to the lid 20 by a rivet 15 and provided at a first end with a ring portion 14A, which the user grasps, and at a second opposite end of a pressure apex 14B. According to what is known, when the container is opened, the tab 14, raised by the user through the ring portion 14A, acts as a fulcrum at the rivet 15, to initiate the opening of the lid 20 by means of a first incision in the pre-cut 21 due to the pressure apex 14B acting in proximity to it. The traction tab 14, which can also have a shape different from that shown in the figures, has been shown in broken lines.

The traction by the user is therefore exerted with a component lying in the plane of the lid 20 according to a traction line 11A (shown dotted in the figures) and with a component outside the plane of the lid 20, schematized with the arrows T1, T2 and T3 in the plan figures which identify an angle β1, β2, β3 with the plane of the lid.

By "traction line" 11A we mean the straight line lying in the plane of the container 20 and passing through the median axis of the tab 14, on which both the rivet 15 and the opposite ends of the tab 14A, 14B lie, along which it is exerted the traction force by the user.

The lid 20 has one or more surface shapes 30, 130, that is to say three-dimensional geometric figures convex with respect to the plane of the lid 20, which identify at least one simple convex central shield 30 or complex 30 ', having convexity both in the longitudinal direction, along a opening line 11B (shown by hatching in the figures), and along a straight line transversal thereto.

Longitudinally, the simple convex shield 30, for example shown in figures 1 to 6, and complex 30 ', for example shown in figures 7 to 9, is identified by a longitudinal convex arc 111, which determines the opening line 11B. It follows that transversally the simple convex shield 30 and complex 30 'is identified by a succession of convex arches orthogonal to the longitudinal convex arch 111.

According to a first embodiment of the invention, the lid bears a single simple convex shield 30, which is therefore composed of a single convex three-dimensional figure, whose geometry defines the longitudinal convex arch 111 and the convex arches orthogonal to it. The longitudinal convex arch 111 can have any orientation with respect to the lid 20.

According to a second embodiment of the invention, the lid bears a single complex convex shield 30 ', which is therefore composed of a plurality of three-dimensional convex figures 130, for example point-like, placed longitudinally in sequence and partially superimposed in the transverse direction at least in pairs a forming the complex shield 30 '. The three-dimensional convex figures 130 in fact identify by interpolation of their upper contours the longitudinal convex arch 111 and consequently the convex arches orthogonal to it. The complex shield 30 ', shown schematically in Figures 7 to 9 and circumscribed with a dotted outline, behaves in all respects during opening like a simple shield 30.

In the case of a 30 'complex shield, the opening direction 11B consists of an average of the geometries of the individual three-dimensional figures 130.

Still according to the invention, the lid 20 can comprise two or more simple 30 'or complex 30' convex shields, even in mixed combinations, placed longitudinally in sequence without mutual overlap.

As shown in Figure 10, the simple shields 30 are placed longitudinally in sequence on the opening line 11B.

According to a further variant, not shown, each of the simple and / or complex shields could have its own opening straight line, in which the opening straight lines are incident to each other.

According to the invention, the straight line of traction 11A can coincide with the straight line of opening 11B, when the straight line of traction passes through the rivet 15 of the tongue 14. Alternatively, the two straight lines can be incident to each other with an obtuse angle α, as shown for example in Figures 11 and 12. In this second case, upon opening the container 10 the user exerts a first traction phase according to the traction line 11A, while once the shield 30, 30 'has been reached, the opening of the container takes place in the direction of the opening line 11B defined by the longitudinal convex arc 111.

Each simple convex shield 30 or complex 30 'defines at opposite ends of its own opening line 11B a head end 31, which determines a load line 22 of the shield, shown in broken line, and a tail end 32, which determines a 23 objective point of aperture.

In any case, the loading line 22 cannot be further upstream in the direction of traction with respect to the rivet 15 of the tab 14, which constitutes the initial opening point of the container 10. Therefore, in cases where the head end 31 is placed between the rivet 15 and the pre-cut 21, that is to say upstream of the rivet 15, the load line 22 in any case passes through the rivet 15, as for example in figures 10 and 13.

In the case of a longitudinal sequence of two or more simple shields 30 or complex shields 30 ', the point of contact of the head end 31 and the tail end 32 of two adjacent shields 30, 30' determine an intermediate objective point 123, subject folding during the opening of the cover 20 (figure 10).

In a container according to the invention, the tail end 32 can be advantageously placed near the pre-cut 21 so that the lid 20 separates integrally from the container body 12.

The maximum preferred extension of a shield 30, 30 'or of a succession in longitudinal sequence of shields 30, 30' goes from the rivet 15 of the tab 14 to the pre-cut 21 on the opposite side of the container 10. According to the invention, at least one shield 30 , 30 'or the longitudinal succession of shields 30, 30' can also have a shorter length.

The convex shield 30, 30 'can be longitudinal or oblique, of any shape, symmetrical or not, have an elliptical shape, vaguely oval or other shapes, provided that the direction of thrust between the various forces in action is compensated and therefore directed towards the target point 23.

The simple 30 or complex 30 'shield can have head ends 31 or tail 32 with rounded, square or acute tip, therefore with any initial or final point. Furthermore, the head 31 or tail 32 ends can be symmetrical or not, both with respect to the opening straight line 11B, and with respect to a straight line transversal thereto.

According to the invention, the longitudinal convex arch 111 and the succession of convex arches orthogonal to it have a convex profile with an increasing / decreasing monotonous trend or a convex profile with an increasing / decreasing trend including bending points.

These profiles can have any shape, that is to say they can include a succession of ridges and valleys and not necessarily continuous growth and descent, even if at variable angles.

In the case of a succession of ridges and valleys, a succession of convex arches partially superimposed longitudinally one to the other is substantially configured, as for example in figure 3 and figure 9.

At their ends, the convex profiles can have a bending point with respect to the plane of the lid 20 or at least some of them gradually fade into the plane of the lid 20 until their height is gradually canceled (Figure 14).

According to a particular embodiment of the invention, for example shown in Figures 15A and 15B, the longitudinal convex arch 111 can have an asymmetrical profile and in particular more pronounced in the first section, i.e. at the end placed on the side of the tongue 14, and be progressively less pronounced in the second section along the traction line 11 in the direction of the target point 23 until its height is canceled out.

The second section of the arch, while presenting minimal convexity, constitutes a line of weakness, which when opening the lid 20 is amplified, forming a longitudinal convex arch 111 more accentuated than the arch before opening.

This amplification effect is particularly pronounced especially if the head end 31 is located near the fulcrum 15 of the tab 14. In fact, in this case, the traction force exerted by the user on the tab 14 in correspondence with the initial portion of the shield 30, 30 'is oriented out of the plane of the lid 20 in a direction substantially orthogonal thereto, according to the arrow T3. Due to the orthogonal orientation of the traction force, (with β3 greater than β2) at the start of the traction, the shield 30, 30 'amplifies its amplitude.

A shield 30 which entirely occupies the cover 20 will cancel the target point 23, figure 10. In this case the stroke will not stop and the cover 20 will tend to detach, unless the final part of the shield 30 is weakened by interrupting the convexity or inserting a depression, not shown in figures 15A and 15B.

Figure 16 shows a further embodiment of the container 10 in which the loading line 22 is located in proximity to the rivet 15. As for the example of Figure 15, the ring portion 14A of the tab 14 is in this case superimposed to the first portion of the shield 30 and should preferably be shaped in a complementary manner thereto in order to reduce the overall dimensions.

If you want to insert a simple 30 or complex 30 'shield that goes from pre-cut 21 to pre-cut 21, but you prefer not to intervene in the area of the ring 14A and the rivet 15, it is possible to bypass them as shown in figure 17.

According to a preferred embodiment of the invention, the lid 20 comprises a first non-shaped surface 24 located laterally and around at least one shield 30, 30 'and preferably extended up to the pre-cut 21. By non-shaped surface we mean a surface without moldings, ribs or other three-dimensional geometric reliefs. This non-shaped surface can be arranged in the horizontal plane of the lid, shown dotted in the figures.

In the event that the loading line 22 is downstream of the tongue 14 along the traction line 11A, a further surface of the cover 20 not shaped 25 is created, between the rivet 15 of the tongue 14 and the loading line 22 .

Advantageously, in particular but not exclusively in this configuration shown in Figures 1A and 1B, the lid 20 can comprise pressure reliefs 26 arranged between the rivet 15 of the tab 14 and the edge 13 of the container for a portion of the perimeter, in order to facilitate the pressure of the tip, to determine a wider initial opening and above all to advantageously keep the non-shaped loading surface 25 flat.

According to the invention, the lid 20 can also include one or more concavities, or depressions, which must always be compensated by convexity, in order not to alter its behavior.

For example, it may include a perimeter concavity 27 around at least one shield 30, 30 'to compensate in height for the convexity of at least one shield 30, 30' (Figures 18A and 18B).

Furthermore, the lid 20 may comprise other concavities, not shown, for example at the load line.

The lid 20 can also advantageously comprise a perimeter stiffening recess 29, shown by way of example in Figures 1A and 1B, but which could be introduced in each of the embodiments shown, placed between the pre-cut 21 and the edge 13 of the container 20.

The figures show by way of example containers 10 of different geometric shape, such as for example containers having a circular, rectangular, beveled or oval shape, as well as different proportions and sizes, bearing one or more simple 30 'or complex 30' convex shields according to the invention. In principle, everything described and shown for each container can be applied in an equivalent way to each of these containers, although some specific shapes and types of shield are particularly advantageous for a different container shape rather than for another.

Furthermore, the convexities mentioned in the present invention can be made by drawing or shaping the laminated metal, or be the result of a mold or a coining, or a 3D printing, or be obtained by overlapping and adhesion (bonding or welding) of other material having the necessary shape.

The opening of the container 10 takes place by traction by the user on the ring end 14A of the tab 14 with a force component in the plane of the lid 20 according to the traction line 11A and a force component outside the plane of the lid 20.

For containers 10 in which there is an unshaped surface 25 in correspondence with the tongue 14, this, during the first phases of opening, behaves in a traditional way with out-of-plane forces arranged in an arcuate manner, identifying a quarter of a circle, as shown schematically by the arrows T1 in the exemplary plan figures. The non-shaped surface 25 allows the lid to be folded up to the loading line (Figure 19A).

Upon reaching the load line 22, a simple 30 or complex 30 'convex shield is intercepted, which is compressed by the energy exerted by the user. The traction is now exerted with a force component out of the oblique plane, schematized in the plan figures with arrows T2, it involves an explosive opening (Figure 19B), until target point 23 is reached (Figure 19C).

During the opening phases, the complex shield 30 'behaves in a way that is completely equivalent to the simple shield 30 and will be jointly described below.

For containers 10 in which there is no non-shaped surface 25 in correspondence with the tab 14, that is to say in which the at least one convex arch 30, 30 'is positioned with its head end 31, which identifies the line of load 22, near the fulcrum 15 of the tongue 14, the shield 30, 30 'is put into compression immediately upon the first traction on the tongue 14 by the user. In this case, the traction is exerted with a force component out of the almost vertical plane, schematized in the figure with the arrows T3, which is advantageous with respect to the ergonomics of the pulling gesture.

In both cases, the geometries described determine that from the moment in which the traction on the lid reaches the load line 22, the convex shield 30, 30 'deforms with an elastic deformation component, collecting the energy that the user exerts. in the initial phase of traction and returning it in an explosive form, using it to open the box. After being loaded by compression without undergoing excessive deformation, in fact, the convex shield 30, 30 'returns the accumulated energy, directing it towards the target point 23 in an oblique direction with respect to the traction, as shown schematically through the arrows F1 in the figures.

In the presence of an unshaped side surface 24, the forces are distributed thereon in the direction of the pre-cut 21 according to the arrows F2 in the figures. The non-shaped surface 24 must remain plastic and yield easily, facilitating the breaking of the pre-cut 21.

Due to this force distribution effect, the separation of the lid 20 from the container body 12 along the pre-cut 21 occurs almost simultaneously, i.e. explosively, up to the tail end 32 of the convex shield 30, 30 ', which constitutes the target point 23, without the need for the user to apply a traction action on the tab 14. In fact, the opening follows the opening line 11B, determined by the geometry of the shield 30, 30 'and not by the action of the user.

In the embodiments in which the tail end 32 is located in correspondence with the pre-cut 21, the lid is completely removed from the container body 12 due to the explosion of forces.

In realizations where the tail end is located at a certain distance from the head-cut 21 significantly different from zero, the lid bends at the target point 23.

The presence of two or more simple 30 or complex 30 'shields in longitudinal sequence determines a sequential work of the same and a consequent folding of the lid 20 between the individual 30, 30' shields. Each of the individual convex shields 30 requires as a traction force only that intended for the separation of the corresponding portion of the lid from the container body. The distribution of tension makes the individual traction phases less tiring, with particular benefit for the first traction phase, which normally requires greater force.

The container according to the invention advantageously allows the control of the explosiveness of the opening and of the vertical traction angles. This occurs by acting on the non-shaped lateral surface 24, when present.

In fact, the smaller the portion of free lateral space from shaping, the more explosive the force will be: the forces will immediately act on the pre-cut area with minimal deformation of the lateral bands. The larger the portion of free space, the lower the explosiveness and the greater the deformation of the side bands, which in the traction phase will accentuate the camber of the lid and release energy in the pre-cut area with delay.

The difference is also in the pull angles out of the plane of the lid. In the first case, since the convex shield 30, 30 'collects and immediately returns the forces, the angle of traction β outside the plane of the lid will be relatively oblique. In the second case, the deformation undergone by the lid causes the angle β to be more oblique and the more tending to the vertical the more deformation the lid undergoes. In this way, you can choose whether to have a more explosive but more rigid opening, or a less explosive but softer one and with an upward traction angle β, more comfortable. By defining the convex shield more, or by leaving it more nuanced (less reactive), you will be able to further control the two options mentioned.

The deformation of the non-shaped lateral surface 24 during the opening phases, which leads to amplifying the profile of the longitudinal convex arch 111 and consequently of the relative transverse convex arches, is more emphasized in the presence of a longitudinal convex arch 111 with asymmetrical profile and in detail more pronounced in the first section. In this case, during opening, the convex shield deforms with a significant component of plastic deformation, which determines the accentuation of the arc with respect to the initial conditions with the container closed, as well as having an elastic deformation component for restitution of the forces towards the sides. The convex arch 111, which is not very pronounced in the initial stages of opening and which takes on a more pronounced appearance during the opening action, is enhanced in its action during the opening itself. The more abundant the non-shaped and yielding bands will be, the more the traction will deform the shield, accentuating its arc.

In addition, the presence of a pronounced spine at the longitudinal arch 111 on a shield 30, 30 'of any shape and with abundant lateral bands 24 optimizes the forces to the maximum, keeping them on the central axis and promoting the maximum possible amplification of the profiles.

Some examples of containers according to the invention capable of optimizing different types of use are: - narrow shield, pronounced spine, abundant side bands: optimizes forces and traction lines; - wide shield: for design needs;

- succession of more consecutive shields: divides the effort;

- shield from precut to precut: an entirely flat panel is obtained after breaking.

The container according to the invention allows the optimization of the lid lifting phase (which occurs suddenly and with minimal effort) stopping the stroke exactly at the target point. The achievement of the goal is the more precise the more pronounced is the design of the final part of the shield, close to the target point. In this way the forces are directed with precision and the bow exhausts its force precisely.

During the lifting phase, the lid 20 no longer bends towards the operator's hands, but tends to bend the cutting part in the opposite direction, reducing the risk of accidental injury.

In addition, the convexity of the lid, once the container is opened, contains any dripping.

The particular shape of the convex shield stiffens in both directions, before opening, the part of the lid that is shaped, making it very resistant. After breaking, however, the lid will remain rigid only in one direction, while in the other, it will retain the ability to bend.

The container according to the invention advantageously allows the use of thin sheets, whose extreme plasticity best accommodates the deformations imposed by the shaped rigid parts.

The main advantage of the container object of the present invention is that it has made opening easier by strengthening the forces collected and multiplied by appropriate geometries.

Advantageously, the lid according to the invention carries the forces to the sides with an optimal angle of incidence for opening the lid.

A further advantage consists in the fact that, once the opening phase has started, it necessarily ends at the target point and does not depend on the action exercised by the user.

The metal container with variable resistance lid for easy opening object of the present invention has the advantage of also optimizing the sense of traction outside the plane of the lid that the user exercises.

Advantageously, the convex shield can be made from any geometric shapes, in compliance with the rules indicated, allowing it to be adapted to the graphic needs of designers.

A further advantage, albeit secondary, consists in having stiffened the lid, solving the problem of discontinuous traction during opening and of the spring effect that known lids create, bending in an arc towards the user's hand with consequent danger of injury and of spray the filling liquid.

The metal container with variable resistance lid for easy opening thus conceived is susceptible of numerous modifications and variations, all of which are covered by the invention; furthermore, all the details can be replaced by technically equivalent elements. In practice, the materials used, as well as the dimensions, may be any according to the technical requirements.

Claims (14)

CLAIMS 1) Metal container with variable resistance lid for easy opening comprising a container body (12) and a lid (20) integral with the container body (12) along a perimeter edge (13), in which the lid (20) is equipped with a perimeter pre-cut (21) adjacent to the edge (13), as well as comprising a traction tab (14) provided at one end with a ring portion (14A) that the user grasps and at the opposite end an apex of pressure (14B), as well as between the two ends of a rivet (15) for joining the lid (20), said lid (20) bearing at least one surface shaping (30, 30 '), characterized in that said surface shaping (30 , 30 ') comprises at least one simple or complex convex central shield (30, 30'), said at least one shield (30, 30 ') being identified by a longitudinal convex arc (111), which determines an opening direction (11B) of the container (10), and transversely by a succession d i convex arches orthogonal to said longitudinal convex arch (111). 2) Container according to claim 1, characterized by the fact that said longitudinal convex arch (111) and said succession of convex arches orthogonal to it have a convex profile with an increasing / decreasing monotone trend or a convex profile with increasing / decreasing trend comprising points of flexion. 3) Container according to claim 2, characterized in that said convex profiles have a bending point with respect to the plane of the lid (20). 4) Container according to claim 2, characterized by the fact that at least some of said longitudinal and / or transverse convex profiles gradually fade into the plane of the lid (20) until their height is gradually canceled out. 5) Container according to claim 1, characterized in that said at least one simple or complex convex central shield (30, 30 ') comprises a single convex three-dimensional figure identifying said at least simple shield (30) or a plurality of convex three-dimensional figures (130 ) placed longitudinally in sequence and partially transversely superimposed at least in pairs to form at least one complex shield (30 '). 6) Container according to any one of the preceding claims, characterized by the fact of comprising alternatively only one simple or complex convex shield (30, 30 ') or alternatively two or more convex shields (30, 30'), simple (30) and / or complexes (30 '), longitudinally in sequence without mutual overlap. 7) Container according to claim 6, characterized by the fact that each simple or complex convex shield (30, 30 ') defines at opposite ends of the opening straight line (11B) a head end (31), which determines a loading line ( 22) of the shield, and a tail end (32), which determines an objective point (23) of opening. 8) Container according to claim 7, characterized in that said tail end (32) is located in proximity of the pre-cut (21) and / or that said head end (31) is located in proximity of the rivet (15) of the tab (14). 9) Container according to any one of the preceding claims, characterized in that said longitudinal convex arch (111) is oriented along a traction line (11A) passing through a median axis of the tab (14). 10) Container according to any one of the preceding claims, characterized in that said lid (20) comprises, laterally to the at least one simple or complex convex shield (30, 30 '), a first unshaped surface (24) and preferably extended up to to the head-cut (21). 11) Container according to claim 10, characterized in that said lid (20) comprises a further non-shaped surface (25), placed upstream of the loading line (22) with respect to the traction direction (11A). 12) Container according to any one of the preceding claims, characterized in that said lid (20) comprises one or more concavities. 13) Container according to claim 12, characterized in that said lid (20) comprises a concave perimeter stiffening recess (27) placed between the pre-cut (21) and the edge (13) of the container. 14) Container according to any one of the preceding claims, characterized in that said lid (20) comprises pressure reliefs (26) arranged between the rivet (15) of the tab (14) and the edge (13).