EP2581210A1

EP2581210A1 - Method for manufacturing a cardboard casket-like container and container obtained therefrom

Info

Publication number: EP2581210A1
Application number: EP12188225.2A
Authority: EP
Inventors: Corrado Zini
Original assignee: Zini Astucci Srl
Current assignee: Zini Astucci Srl
Priority date: 2011-10-12
Filing date: 2012-10-11
Publication date: 2013-04-17
Anticipated expiration: 2032-10-11
Also published as: ITFI20110221A1; EP2581210B1

Abstract

A casket-like container comprising two mutually hinged semi-shells. A method for manufacturing the container comprises the steps of arranging, for each semi-shell, a cardboard blank comprising a central bottom portion (1) and a plurality of flaps (2, 21) foldably projecting from respective sides of said central portion, said flaps comprising a hinge-supporting flap (21) having an inner transversal folding line (21b), forming in the hinge-supporting flap a slot (4) along the transversal folding line, said slot comprising a central cutout (40) that extends towards the free end of the flap, folding said blank to form side walls from said flaps, the hinge-supporting flap defining a hinge edge provided with said slot, and connecting the semi-shells by inserting an elastic hinge device (8) in said slots and distributing a gluing substance in said cutouts.

Description

The present invention concerns the field of cardboard containers, typically covered cardboard, and in particular regards a method for manufacturing, with such material, a casket-like container, e.g. a container with hinge-folded base and cover and a spring-hindered opening. The invention extends to a casket-like container obtained thereby, mainly destined to be used as packing box for valuable objects such as jewels and watches.
Containers of this kind are well known and largely used in various shapes and materials, first of all wood and thermoplastic materials. Prior solutions, however, generally arise problems of production complexity and costs (these costs to be added to those of the material itself), which are anything but minor, especially in a more and more competitive market interested in any possible economy setting off a decrease in the retail price and an increase in the quality perceived for the same price.
Applicant has now surprisingly identified a method allowing for the manufacture of containers like the ones mentioned above, with a simple operational mode and a remarkable reduction in production costs, at the same time guaranteeing a qualitative result both for stiffness and appearance of the container, totally meeting the standards of similar containers presently is use.
These results are obtained with the method and the container according to the present invention, the essential features of which are defined by the first and the tenth of the appended claims.
The characteristics and advantages of the method for manufacturing a cardboard casket-like container and of the container obtained thereby according to the present invention will be apparent from the following description of an embodiment thereof, given as a non-limiting example with reference to the attached drawings, wherein:

figure 1 is a flat blank destined to form one of the complementary two halves or semi-shells of the casket-like container according to the invention;
figures from 2a to 4b are prospective views of the two halves of the container in the subsequent steps of the manufacturing method according to the invention, starting from respective flat blanks similar to the one in figure 1, with figures 2a, 3a, 4a referring to one of the halves, and the remaining figures 2b, 3b and 4b referring to the other half.

figure 5 is a perspective view of the assembled casket-like container, open, to be completed with known and usual finishing;
figure 6 is an enlarged particular of the container in figure 5 in the area of the elastic hinge device;
figure 7 is an axonometric outline of the container in the area of the hinge device, seen from the back side external to the container itself;
figure 8 is a perspective view of the area of the hinge device of a container obtained according to a different embodiment with respect to the one in the previous figures; and
figures 9a and 9b show a flat blank, in two different folding steps, obtained according to the embodiment in figure 8.

With reference to the figures from 1 to 7, the invention provides for the manufacture of a cardboard casket-like container comprising two mutually hinged semi-shells with an elastic hindrance against the opening rotation, a locking snap in the opening position, and an elastically urged rotation towards the opening position, wherein the two semi-shells, mutually facing at the concave sides, combine to form a closed container. The hinge device adapted to perform such functionality is a (generally metallic) device already known, the specific characteristics of which will in any case be dealt with afterwards.
Each semi-shell is obtained from a cardboard flat blank. In the example, the container has the shape of a parallelepiped and is therefore formed by two square-angled semi-shells with a quadrilateral basis, but other shapes can obviously be obtained with the same or with similar methods. The two semi-shells can be identical or have different heights (e.g. in the orthogonal direction with respect to the bottom) as in the example shown, in which the half or semi-shell destined to form the support base of the container is slightly higher than the half destined to form the cover. Generally, the two halves can be completely interchangeable from this point of view, that is to say that both can equally function as base or as cover; one of the two functions can in any case be assigned to either half during the finishing phase of the packaging.
Remaining on the example, the blank (figure 1) comprises a central portion 1 with a quadrilateral shape like the semi-shell bottom which will result from, and consist in, the above mentioned portion. From the sides of the central portion 1, respective flaps 2 project in a foldable manner intended to form, as a result of their very folding, side walls which will rise from the central portion or bottom 1. Therefore, each flap 2 has a base folding line 2a, 21a which separates it from the central portion 1. At least one of the flaps, indicated as 21 and representing a hinge-supporting flap because, as discussed hereafter, designed to form the wall of the semi-shell which is hinge-connected to the other semi-shell, but preferably also the remaining flaps, present also an inner transversal folding line 2b, 21 b. Thanks to this inner folding line, each side wall will become doubled in width, e.g. formed by two superimposed cardboard sheet portions. As apparent, the folding lines are represented for the ease of clarity with a dotted line, while the continuous lines are to be intended as cutting lines.
The flaps 2 can also present, as in flap 21 in figure 1 (but not in the remaining figures) perimetrical indentations 31 and/or holes 32, the first having a structural function, and both for improving the steadiness of the assembled container.
Turning again to the hinge-supporting flap 21, a slot 4 is formed in correspondence with its inner folding line 21 b, that, according to the present embodiment, extends along the central part of such folding line. Two or more slots distributed along the folding line could in fact be provided, as positively shown hereafter.
More precisely, still according to this embodiment, the slot 4 interrupts the folding line with a cut 41 that is slightly displaced towards the base of the flap, of an extent indicated with S in figure 1. From cut 41, a cutout 40 develops in central position and extends towards the free end of the flap, e.g. on that part that, once the semi-shell is formed, will be the inner sheet of the relative side wall. The slot 4 also comprises, on one of the two halves of the cut 41 divided by the cutout 40, and always starting from the cut itself towards the free end part of the flap, a hollow segment 42, resulting from the removal of a stripe of material and, therefore, with detached/spaced cutting edges.
The arrangement of the slot as described above exemplifies a solution adapted to suitably house the hinge device and to make easier the removal of material necessary to obtain the central cutout 40 without wastes and without weakening the structure of the flap and of the side wall formed by it, but it can clearly be subject to construction alternatives, as shown afterwards, being it understood the importance of at least one central cutout 40.
With reference now also to the remaining figures up to figure 7, a method for manufacturing the casket-like container according to the invention first of all provides for the folding of the side flaps 2 first along the inner folding lines (figures 2a and 2b) and then along the base folding lines (figures 3a and 3b) so as to orthogonally elevate from bottom 1 side walls 2 with double width. Such arrangement, which results in the desired semi-shell shape for the two halves of the container, will be in practice obtained and made steady (to be noted in this respect the tape pieces which join the corners of the semi-shells) with technical means and expedients (elevation, corner-joining, gluing) common in the paper and cardboard field and not described in details herein. A further shaped cardboard sheet can also be provided, both to strengthen the bottom and to prevent the elastic return or re-opening of the inner sheets of the walls, to be fit inside the semi-shell, superimposed on the bottom itself. Moreover, still with a strengthening function, a reinforcement made of cardboard or even of other strengthening materials, can be inserted and made integral between the two folded parts of the side flaps, in particular in correspondence with the hinge-supporting flap.
The procedures and devices for covering the two semi-shells with a pre-glued covering sheet 6 (figures 4a and 4b) will also be the usual ones. The sheet 6 preferably comprises, for at least one of the two semi-shells, a window or excised portion in the covering flap of the hinge-supporting wall, so as to let the slot 4 free and accessible. In figure 5, which will be dealt with in details later on, it can be noted that one of the two semi-shells (the one forming the cover of the container) has a sheet 6 with a predefined regular window 7, while on the other semi-shell (the base) the slot remains accessible due to the belated positioning of the (unbroken) covering flap, which is in fact positioned later on so as to make it adhere, instead of to the inner side of its own semi-shell pursuant to a folding thereupon, to the outer side of the other semi-shell so as to coat the hinge and make it invisible, thus improving the appearance of the casket-like container. However, two covering sheets both with windows such as the window 7 can be made use of.
With particular reference to figures 4b, 5 and 6, a hinge device 8 with elastic hindrance is inserted and made stable in the slots 4 of the semi-shells, so as to achieve the assembly of the casket-like container. The hinge device 8, one for each corresponding pairs of slots which, as said, can also be two or more, is a device already known and comprises two small plates 81, generally metallic, mutually articulated along a hinge axis. In central position, a flexion plate spring 82 (visible, in particular, in figure 6) tightens the two small plates being wound in a C-shaped fashion around the hinge axis, thus functioning as an elastic hindrance opposing the mutual rotation of the two small plates, both starting from an opening position, and from a mutual closing position, and assisting then a snap release towards said positions once the rotation has been driven and is approaching its stop point.
The above mentioned spring 82 causes a projection which, by inserting the small plates 81 in the slots 4 of respective semi-shells, becomes housed by the central cutout 40. The latter becomes placed on the inner flap of the side wall and is only partially occupied by the spring (see again figure 6); the space thus made available is used to lay a certain quantity of additional glue which penetrates the two sheets of the wall and perfections the integration of the small plate on the body of the wall itself and between the two sheets of the latter.
Thanks to this particular expedient, the activation of the opening and closing movements of the casket-like container proves to be perfectly precise and easy, with a perception of high quality because lacking settlement plays or noises between the small plates 81 and the relative walls of the semi-shells. A further contribution to integration can also come from the laying of glue in the indentation(s) 31 and in the holes 32, the position of which can advantageously be designed so as to make them correspond with the longitudinal ends of the small plates 81; in this way further points of mutual integration among the three layers (the two sheets and the metallic small plate inserted between them) are added in such positions. Besides such distributions of glue specifically aimed at the hinge device, the two sheets of the wall can obviously be made mutually adhere by means of other glue applications which generically concern their surface development, such as two glue stripes orthogonal with respect to the bottom at the two sides of the slot.
By coupling the two semi-shells, which from this point of view as well are identical and not mirrored, the hollow segment 42 of the slot of a semi-shell corresponds to the linear cut segment 41 of the other semi-shell. Such arrangement can help balance the strengths at stake and in its turn particularly stabilizes the assembly with the hinge which is completely superimposed by the cardboard sheet on at least a small plate on both sides of the central spring, this without causing any interference with the sheet of the opposite semi-shell. Again, be it noted, with reference to figure 7, that the displacement between the cut 41 and the folding line 21 b makes the pivot 83 of the hinge device, e.g. the mutual junction of the two small plates 81 around the rotation axis, be housed in and made integral with the two hinge-supporting walls without causing projections or interferences. To this purpose, the above mentioned displacement will preferably correspond to half the diameter of the pivot. The width of the hollow segment will be bigger than or at least equal to the diameter of the pivot, being it understood that the possibility of reducing such width will be subject to technological limits.
The manufacture of the casket-like container will be then completed with all the necessary finishing and customization operations, as known in the field. In particular, the semi-shells will be provided with fillings and/or supporting elements for the articles contained therein, with external decorations, etc..
With reference now to figures 8, 9a and 9b, a different embodiment of the invention, represented in a casket-like container with two hinge devices placed side by side (and, therefore, with a corresponding number of pairs of slots on the two semi-shells) provides for the use of simplified slots 104. These slots can result advantageous from a productive point of view, having in any case a fully acceptable overall functionality and being able to attain the desired result. In particular, on the free end part of the flap (inner part of the wall once the container is formed), the slot 104 simply provides a central cutout 140, similar to the cutout 40 of the first embodiment, placed between two side cutouts 140a, for example with wave-like symmetrical profiles with respect to the central cutout, the tangent at the wave curve being substantially parallel to the folding line at the junction point with the central cutout and substantially orthogonal to the folding/corner of the slot's end. The side cutouts 140a attain results similar to those illustrated for the stripe hollow segments of the previous embodiment, since they can also be used to apply a further layer of glue.
Thanks to the method according to this invention it is therefore possible to provide cardboard casket-like containers the functionality and perceived quality of which equal the known containers made of stiff material such as wood or thermoplastic materials, which are more expensive (as to wood) and have a more severe environmental impact. The mechanical solidity of the casket-like container is moreover really surprising considering the low intrinsic strength of the start raw material; for this reason, it can be certainly stated that the invention overcomes a technical prejudice. As seen, the manufacturing operations are elementary and can be carried out with known means and equipments. The initial blank presents a rational shape minimizing material waste, and represents a substantial advantage in terms of warehouse spaces (and costs), all the more so considering that both the semi-shells of the casket-like container can be obtained with the same and only kind of blank.
The folding lines pre-arranged on the blank will be obtained through cuttings or so-called "half cuts", or with other similar solutions known in the paper and cardboard field.
The present invention has been here described with reference to its preferred embodiments. It should be understood that that there may be other embodiments within the same inventive concept, all defined by the scope of protection of the following claims.

Claims

A method for manufacturing a casket-like container comprising two mutually hinged semi-shells, the method comprising the following steps: arranging, for each semi-shell, a cardboard flat blank comprising a central portion (1), intended to form a bottom of the semi-shell, and a plurality of flaps (2, 21) foldably projecting from respective sides of said central portion, said flaps comprising a hinge-supporting flap (21), at least said hinge-supporting flap having an inner transversal folding line (21 b); forming in the at least one hinge-supporting flap (21) at least one slot (4) in correspondence with, and along, the transversal folding line (21 b), said slot (4) comprising a central cutout (40) that extends over at least the part of the flap (21) towards the free end; folding said blank so as to form with said flaps respective side walls of each semi-shell, the hinge-supporting flap (21) defining a hinge corner provided with said at least one slot (4), as a result of a fold along said transversal folding line; mutually connecting the two semi-shells by inserting an elastic hinge device (8) in the slots of the semi-shells and making the device integral therewith, in said connection step a certain amount of a gluing substance being distributed at least in said central cutouts (40) of said slots.
The method according to claim 2, wherein said semi-shells, before mutually connecting, are lined with respective covering sheets (6), at least one window (7) being formed in the covering sheet of at least one semi-shell, said window being adapted to correspond with said at least one slot.
The method according to claim 1 o 2, wherein at least one said slot (4) centrally interrupts said folding line (21 b) with a linear cut (41) parallel with said folding line and displaced with respect to the same towards the base of the flap, thereby the slot, once the corresponding wall is formed, is adapted to form a seating for housing and incorporating a pivot (83) of said hinge device (8), said cutout (40) extending in a central position starting from said linear cut, said slot (4) further comprising, on one of the two halves of said linear cut divided by said cutout, and again starting from the same linear cut towards the free end of the flap, a hollow stripe segment (42).
The method according to claim 3, wherein said linear cut (41) is displaced with respect to said folding line of a displacement amount (S) that is about half the width of said pivot (83), said hollow stripe segment (42) having an extension, measured orthogonally to the folding line, that is at least double than said displacement amount (S).
The method according to claim 3 or 4, wherein by connecting the two semi-shells via said at least one device in each pair of slots the hollow stripe segment (42) of the slot of a semi-shell corresponds to the linear cut segment (41) of the other semi-shell.
The method according to claim 1 or 2, wherein at least one said slot (4) centrally interrupts said folding line (21 b) with a linear cut (41) parallel with said line and displaced with respect to it towards the base of the flap, so that the slot, once the wall is formed, is adapted to form a seat to house and incorporate a pivot (83) of said hinge device (8), said cutout (140) developing in central position starting from the linear cut, said slot (104) further comprising, on the two sides of said linear cut divided by said cutout, and always starting from the very cut towards the free end of the flap, two side cutouts (140a) with wave-like profiles symmetrical with respect to the central cutout, the tangent at the wave curve being substantially parallel to the linear cut at the junction point with the central cutout and substantially orthogonal to the cut at the end of the slot.
The method according to any of the previous claims, wherein said hinge-supporting flap (21) has one or more indentations (31) or holes (32), adapted to receive further amounts of said gluing substance, the holes being in particular formed in correspondence with the position of the longitudinal ends of the hinge device (8).
The method according to any of the previous claims, wherein all the flaps (2, 21) of the blank have respective inner transversal folding lines, so that when the semi-shells are formed each side wall has a doubled width as a result of the superimposition of the two parts of the flap.
The method according to claim 8, wherein said blank is developed cross-like with four flaps (2, 21) foldably projecting from the respective sides of a quadrilateral central portion (1).
The method according to any of the previous claims, wherein an additional sheet of outlined cardboard is fit inside each semi-shell superimposed on the bottom, for strengthening the bottom and opposing the elastic return or re-opening of the flaps forming the walls.
A casket-like container comprising two semi-shells mutually hinged, each semi-shell being obtained by folding a cardboard flat blank and comprising at least a hinge-supporting wall with two parts of the cardboard flap superimposed, at least one slot (4) being obtained on a free corner of such wall, comprising a central cutout (40) interesting at least the inner part (21) of the side wall; the two semi-shells being connected by an elastic hinge device (8) inserted in and made integral with each pair of corresponding slots of the two semi-shells, the integration providing for a certain amount of gluing substance at least in said central cutouts (40) of the slots.
The container according to claim 11, wherein said semi-shells are covered with respecting covering sheets (6), on the covering sheet of at least one semi-shell a window (7) being formed, adapted to correspond with said at least one slot.
The container according to claim 11 or 12, wherein an additional sheet of shaped cardboard is fit inside each semi-shell superimposed on the bottom, strengthening the bottom and opposing the elastic return or re-opening of the flaps forming the walls.
The container according to any of the claims from 11 or 13, wherein said at least one slot (4) comprises a linear cut displaced with respect to the corner on the external part of the hinge-supporting wall, the slot thus forming a seat to house and incorporate a pivot (83) of said hinge device (8), said cutout (40) developing in central position starting from said linear cut, said slot (4) further comprising, on one of the two sides of said linear cut divided by said cutout, a stripe hollow segment (42) on the inner part of the wall.
The container according to any of the claims from 11 to 13, wherein the at least one said slot (104) comprises a linear cut displaced with respect to the corner on the external part of the hinge-supporting wall, the slot thus forming a seat to house and incorporate a pivot (83) of said hinge device (8), said cutout (140) developing in central position starting from said linear cut, said slot (104) further comprising, on the two sides of said linear cut divided by said cutout, and still starting from the very cut and on the inner part of the wall, two side cutouts (140a) with wave-like profiles symmetrical with respect to the central cutout, the tangent at the wave curve being substantially parallel to the linear cut at the junction point with the central cutout and substantially orthogonal to the cut at the end of the slot.