ITMO20070322A1 - ITEMS HAVING AT LEAST A PASS-THROUGH OPENING, EQUIPMENT AND METHODS TO OBTAIN OBJECTS WITH AT LEAST A PASS-THROUGH OPENING - Google Patents

Description

Description of industrial invention

Objects having at least one through opening, apparatuses and methods for obtaining objects having at least one through opening

The invention relates to objects having at least one through opening and apparatuses and methods for obtaining such objects. The objects having at least one through opening can be capsules suitable for containing a powder preparation from which it is possible to obtain a drink, for example coffee, tea or the like. Alternatively, the objects having at least one through opening can be portions of containers such as tube necks for toothpaste or other products, or bottle necks.

Capsules or filters are known comprising a casing suitable for receiving a product, for example a powder preparation for obtaining a drink. The casing comprises a side wall, which extends around a longitudinal axis and which is delimited transversely to the longitudinal axis by an upper wall and a lower wall. The upper wall is coupled to the side wall after the preparation has been introduced into the capsule. The lower wall and the side wall can be obtained in one body.

The lower wall acts as a filter and is provided with a plurality of through openings extending substantially parallel to the longitudinal axis. These openings, during the use of the capsule, allow the preparation to come out of the casing so as to obtain a drink, such as coffee, tea, milk.

The capsules described above can be made by means of apparatuses for injection molding of plastic material. These apparatuses allow to obtain the openings of the lower wall during injection molding inside a forming chamber, without having to subsequently resort to further processing. However, injection molding apparatuses are structurally very complex and therefore are quite expensive.

Furthermore, in order for the plastic material to flow correctly into the molding chamber, the plastic material must be heated to a temperature such as to be suitably fluid, which requires a considerable expenditure of energy.

The capsule openings just described have geometries and orientations which cannot be freely chosen, but depend on limits imposed by the injection molding apparatuses used to obtain such caps. For example, the dimensions of the openings cannot fall below certain values due to the geometric tolerances and resistance limits of the aforementioned devices.

Compression molding allows you to overcome many defects of injection molding. However, compression molding cannot currently be used to form objects provided with a plurality of small openings, for example capsules containing a beverage preparation, for the reasons explained below.

Known apparatuses for compression molding comprise a male mold element and a female mold element. During operation, a dose of plastic material is introduced between the male mold element and the female mold element and compressed between these two elements, so as to be shaped according to the desired geometry. Even if high pressures are used, a thin layer of plastic material always remains interposed between the male mold element and the female mold element, which makes it impossible to obtain objects provided with through openings. Further cold working is therefore necessary, which produces waste material and entails a general increase in process costs. Furthermore, cold working triggers tensions in objects that can damage them.

It is known to use compression molding apparatuses to obtain objects provided with through openings of relatively large dimensions, such as necks of tubes for toothpaste. However, these apparatuses require the use of annular doses of plastic material. The annular doses, in order to be adequately processed, must be positioned with a certain precision inside the mold so that the opening in the formed object is obtained correctly. This makes the production process more complicated and therefore more expensive than in the case in which non-annular and compact doses are processed, for example with a discoidal or substantially spherical shape.

An object of the invention is to improve the apparatuses and methods for obtaining objects having at least one through opening.

Another object is to provide apparatuses and methods which allow to obtain objects having at least one through opening in a simple, fast and economical way without generating waste materials.

A further object is to obtain objects provided with through openings whose geometry and orientation can be chosen more freely with respect to the state of the art.

In a first aspect of the invention, a method is provided comprising the steps of:

shaping a material by means of first forming means and second forming means cooperating with each other to form an object,

obtaining on said object at least one through opening,

characterized in that said forming comprises moving said first forming means and said second forming means relative to each other so as to apply a shear force on said material which separates adjacent areas of said material to generate said at least one through opening.

In one version, said application comprises moving said adjacent areas relative to each other to create a discontinuity in said material defining at least one through opening.

Said material can be a plastic material which is at a temperature at which said plastic material is deformable.

In a further version, said shaping comprises compression molding said material between the first forming means and the second forming means.

Said material can comprise a dose of plastic material separated by an extruder device, or a mixture of at least one metallic material and a plasticizer substance.

In another version, said shaping comprises thermoforming a sheet material interposed between the first forming means and the second forming means. Said object can be a capsule adapted to contain a preparation for a drink. In this case, the object comprises a plurality of through openings included in a capsule filter.

In a second aspect of the invention, an apparatus is provided for forming an object having at least one through opening, comprising first forming means and second forming means mutually cooperating to obtain said object from a material in a forming position, characterized in that a first portion of said first forming means and a second portion of said second forming means are mutually sliding in said forming position, so as to apply a shear force on said material which separates adjacent areas of said material to generate said at least one opening passerby.

Thanks to the first and second aspects of the invention, it is possible to obtain an apparatus and a method capable of simplifying the production of objects having at least one through opening. Such objects can thus be obtained more quickly than in the state of the art, since the at least one through opening is defined directly by the first forming means and by the second forming means, without requiring further processing. This makes it possible to make the production process also very economical. Moreover, thanks to the fact that the at least one through opening is obtained by means of a shear force exerted by the first forming means and by the second forming means, the drawbacks of known apparatuses, in which the material is forced to flow through narrow passages, are eliminated. to generate through openings.

The method and the apparatus according to the first two aspects of the invention allow to form at least one through opening when the material, from which the object is obtained, is heated to a temperature at which such material is deformable. This avoids the formation of tensions that generally occur when the through openings are obtained by cold working.

Furthermore, the forces necessary to obtain the at least one through opening are considerably reduced when compared with the forces applied during cold working.

Finally, thanks to the first two aspects of the invention it is possible to obtain at least one through opening without producing waste materials, which involves a reduction in production costs.

In a third aspect of the invention, a capsule is provided suitable for containing a powder substance for preparing a beverage, comprising a side wall extending around an axis and a filtering wall provided with a plurality of through openings, characterized in that the through openings of said plurality of through openings open onto at least one surface substantially parallel to said axis.

In a fourth aspect of the invention, a capsule is provided suitable for containing a powder substance for preparing a beverage, comprising a side wall extending around an axis and a filtering wall provided with a plurality of through openings, characterized in that said capsule is obtained by compression molding. Thanks to the third and fourth aspects of the invention, it is possible to obtain capsules quickly and economically. Furthermore, the through openings of the capsules according to the third and fourth aspects of the invention have geometries and orientations that can be chosen more freely than the capsules of the state of the art.

In a fifth aspect of the invention, a method is provided for forming an object having a through opening, comprising the steps of:

providing a precursor of said object, said precursor having a wall in a position in which it is intended to obtain said through opening; breaking said wall to obtain wall portions arranged around said through opening; shaping said wall portions to define an edge region of said through opening.

In a sixth aspect of the invention, an apparatus is provided for forming an object having a through opening, comprising breaking means for breaking a wall of a precursor of said object, so as to obtain wall portions arranged around said through opening, said apparatus further comprising shaping means for shaping said wall portions so as to define an edge area of said through opening.

Thanks to the fifth and sixth aspects of the invention, it is possible to obtain objects having a through opening, such as for example necks of tubes for toothpaste, in a simplified manner with respect to the state of the art. In fact, in the state of the art, in the case of tube necks obtained by injection molding there are high production costs linked to the structural complexity of the molding apparatuses and to the fact that the plastic material must be brought to a high temperature to ensure the correct fluidity.

In the case of tube necks obtained by compression molding, it is necessary to use annular doses of plastic material and position them precisely in the mold so that the formed object has a good quality through opening.

The costs associated with the production of objects having a through opening are thus reduced. The invention will be better understood and implemented with reference to the attached drawings which show exemplary and non-limiting forms of implementation, in which:

Figure 1 is a longitudinal section of an apparatus for obtaining a capsule suitable for containing a beverage preparation;

Figure 2 is an enlarged section of a portion of the apparatus of Figure 1;

Figure 3 is a schematic and sectional view showing an apparatus according to the invention in a first operating configuration;

Figure 4 is a schematic and sectional view showing the apparatus of Figure 3 in a second operating configuration;

Figure 5 is a schematic and sectional view showing the apparatus of Figure 3 in a third operating configuration;

Figure 6 is a further schematic and sectional view of the apparatus shown in Figure 3, in the first operating configuration;

Figure 7 is a further schematic and sectional view of the apparatus shown in Figure 3, in the second operating configuration;

Figure 8 is a further schematic and sectional view of the apparatus shown in Figure 3, in the third operating configuration;

Figure 9 is a schematic perspective view showing a version of an apparatus and an object provided with through openings obtained by means of this apparatus;

Figure 10 is a perspective view, enlarged and interrupted, showing the apparatus and the object of Figure 9;

Figure 11 is a top view of a portion of the object of Figure 9 or 10;

Figure 12 is a view like that of Figure 11, showing a portion of the object of Figure 9 on a side opposite to that of Figure 11;

Figure 13 is a schematic perspective view showing another version of an apparatus and another object provided with through openings obtained through this apparatus;

Figure 14 is a perspective view, enlarged and interrupted, of the apparatus and the object of Figure Figure 15 is a further perspective view of the object of Figure 13;

Figure 16 is a perspective view, enlarged and interrupted, showing a detail of Figure 15;

Figure 17 is a schematic perspective view showing a further version of an apparatus and a further object provided with through openings obtained by means of this apparatus;

Figure 18 is an enlarged and interrupted perspective view of the apparatus and object of Figure 17;

Figure 19 is an enlarged and interrupted perspective view of the object of Figure 17;

Figure 20 is a perspective view of a container neck provided with a through opening;

Figure 21 is another perspective view of the container neck of Figure 20;

Figure 22 is a partially sectioned perspective view of the container neck of Figure 20 and of an apparatus for obtaining this container neck; Figure 23 is a perspective and sectional view showing an apparatus for forming an object provided with a through opening, for example a container neck, in a first working configuration; Figure 24 is a view like that of Figure 23, showing the apparatus in a second working configuration;

Figure 25 is a view like that of Figure 23, showing the apparatus in a third working configuration;

Figure 26 is a perspective and partially sectioned view of the object obtained in the first working configuration shown in Figure 23;

Figure 27 is a perspective view of the object obtained in the second working configuration shown in Figure 24;

Figure 28 is a perspective view of the finished object obtained in the third working configuration shown in Figure 25;

Figure 29 is a schematic view, interrupted and in section, of an alternative version of the apparatus of Figure 1, in a first operative position;

Figure 30 is a view like that of Figure 29, showing the apparatus in a second operating position;

Figure 31 is a view like that of Figure 29, showing the apparatus in a third operating position;

Figure 32 is a plan view of a portion of an object which can be obtained through the apparatus of Figure 29;

Figure 33 is a perspective view of the portion of the object of Figure 32;

Figure 34 is an enlarged perspective view showing the object of Figure 32 on the opposite side to that of Figure 33;

Figure 35 is a plan view showing a portion of an object which can be obtained by means of the apparatus of Figure 29, in an alternative version;

Figure 36 is a perspective view of the portion of the object of Figure 35;

Figure 37 is an enlarged perspective view showing the object of Figure 35, on the opposite side to the part visible in Figure 36.

An apparatus 1, shown in Figures 1 and 2, is provided with first forming means, comprising for example a female mold element 2, and with second forming means, comprising for example a male mold element 3.

The female mold element 2 and the male mold element 3 are mutually movable along a molding direction S between a closed or forming position, shown in Figures 1 and 2, and an open position not shown. In the forming position, between the female mold element 2 and the male mold element 3 there is defined a forming chamber having a shape substantially corresponding to the object to be obtained. In the open position, the formed object can be moved away from the first forming means and from the second forming means.

For example, the female mold element 2 can be movable along the molding direction S, while the male mold element 3 is fixed, or vice versa, the male mold element 3 can be movable while the female mold element 2 is fixed. It may also happen that the female mold member 2 and the male mold member 3 are both movable along the molding direction S.

The female mold member 2 and the male mold member 3 cooperate to compression mold a compact dose 10 of plastic to form an object, such as a capsule 4. The dose 10 has previously been separated from an outgoing material from a extruder device.

The dose 10 can be made entirely of plastic or, in one version, it can comprise a mixture of at least one metallic material and a plasticizer. The metallic material may comprise aluminum. The metallic material can be powdered, while the plasticizer substance acts as a binder and provides plasticity to the metallic material. In any case, whatever the metallic material, the capsule, once formed, can be cooled and subjected to a treatment to eliminate the plasticizing substance, for example to a debinding treatment. Subsequently, the capsule can be subjected to a heat treatment such as sintering or compaction.

The capsule 4 has a circular plan shape, but it can also have other geometric shapes.

The capsule 4 acts as a container and / or filter for a product, for example a powder preparation from which it is possible to obtain a drink, for example coffee, tea or the like.

The female mold element 2 comprises a matrix 5 which defines a cavity 15 intended to receive the dose 10 to be shaped.

The matrix 5 is provided with a shaping side wall 6, suitable for shaping an external lateral surface 8 of the capsule 4, and with a shaping base wall 7, suitable for shaping an external base surface 9 of the capsule 4.

The shaping base wall 7 is provided with a plurality of forming recesses 16 and forming reliefs 17, arranged inside the cavity 15 (better shown schematically in Figures 3 to 8). The forming recesses 16 and the forming reliefs 17 are distributed alternately in ways that will be described in more detail with reference to different versions of the apparatus 1.

The male mold element 3 comprises a further shaping side wall 11, suitable for shaping an internal lateral surface 12 of the capsule 4, and a further shaping base wall 13, suitable for shaping an internal base surface 14 of the capsule 4.

The further shaping base wall 13 comprises a plurality of forming protrusions 18. A corresponding forming zone 19 is defined between a forming protrusion 18 and a further forming protrusion 18 adjacent to it.

Each forming protrusion 18 is delimited by two operating surfaces 20, shown in Figures 3 to 8, which can extend parallel to the molding direction S. The two operating surfaces 20 delimit two faces of the forming protrusion 18 opposite each other.

Each forming relief 17 of the matrix 5 is laterally delimited by further operating surfaces 21 intended to interact with the operating surfaces 20. In particular, the operating surfaces 20 can slide relative to the corresponding further operating surfaces 21, or vice versa, so as to apply on the plastic material a shear force such as to separate adjacent areas of the plastic material, and thus generate a through opening, as will be described in greater detail below.

Figures 3 to 8 schematically show the operating principle of the apparatus 1 in different phases during the compression molding of the dose 10.

Initially, the dose 10 is introduced into the matrix 5, as shown in Figures 3 and 6, after which the male mold element 3 and the female mold element 2 are mutually approached so as to compress the dose 10 as shown in Figures 4 and 7. In the example shown, the female mold element 2 is moved upwards so as to approach the male mold element 3, which remains fixed.

While the male mold element 3 penetrates inside the matrix 5, each forming protrusion 18 is received in a corresponding forming recess 16. Similarly, the forming ridges 17 are received in the forming zones 19.

In the example shown, the forming recesses 16 have the shape of grooves, for example rectilinear. These grooves can be parallel to each other and to a diameter of the shaping base wall 7. The forming ridges 17 also extend continuously between two opposite regions of the shaping side wall 6. The forming ridges 17 can be parallel to a diameter of the shaping base wall 7 and have, for example, a rectilinear shape.

As can be seen in Figures 6 to 8, the forming protrusions 18 do not extend continuously between two opposite regions of the shaping side wall 6. On the contrary, the forming protrusions 18 can be shaped as prismatic elements or in the shape of a truncated pyramid which project from a lower surface of the male mold element 3.

A plurality of forming protrusions 18, arranged along a rectilinear zone, penetrates inside the groove defined by the corresponding forming recess 16, and crushes a certain fraction of plastic material which is interposed between the forming protrusions 18 and the corresponding forming recess 16, forcing it to flow in the areas not occupied by the forming protrusions 18, i.e. in the areas that separate two adjacent forming protrusions 18, housed in the same forming recess 16.

At the same time, the operating surfaces 20 come into contact with corresponding further operating surfaces 21, sliding relative to each other, so as to subject the plastic material to a cutting action which allows to obtain a discontinuity in the plastic material, from which a through opening of the capsule 4. This is clearly visible from a comparison of Figures 4 and 7 respectively with Figures 5 and 8. The through opening thus obtained opens onto a surface of the capsule 4 not perpendicular to the molding direction S, for example on a surface of the capsule 4 parallel to the molding direction S.

It is possible to adjust the reciprocal movement of the male mold element 3 and of the female mold element 2 in such a way that each forming protrusion 18 penetrates inside the corresponding forming recess 16 by a certain amount so as to obtain through openings having dimensions you want. The extension of the through openings, in other words, is determined by making the operating surfaces 20 and the further operating surfaces 21 slide relative to each other by an appropriate amount. Thanks to this, it is possible to obtain caps having through openings whose extensions can be chosen more freely simply by modifying a final closing position of the male mold element 3 and of the female mold element 2, without having to modify the apparatus. The production process is thus simplified, reducing costs.

Figures 9 and 10 schematically show a first version of the apparatus 1, which operates according to the operating principle described above. In this version, the forming protrusions 18 are arranged radially, with respect to the molding direction S. In other words, the forming protrusions 18 are formed along concentric circumferential areas of the lower surface of the male mold element 3. The forming protrusions 18 are positioned such that the operating surfaces 20 extend circumferentially, i.e. along concentric cylindrical surfaces.

The forming reliefs 17 and the forming recesses 16, in this version, are circular in shape and concentric. In other words, the forming recesses 16 have the shape of circular grooves. The forming reliefs 17 have the shape of continuous circular ribs. Each forming recess 16 is interposed between two adjacent forming reliefs 17.

Each forming recess 16 is therefore delimited by a pair of further operating surfaces 21 facing each other.

When the forming protrusions 18 arranged along the same circumference penetrate a corresponding forming recess 16, the two operating surfaces 20, with which each forming protrusion 18 is equipped, come into contact with a respective further operating surface 21 delimiting the forming recess 16. The plastic material interposed therein is moved towards the bottom of the forming recess 16 and into the space between two adjacent forming protrusions 18. The further operating surfaces 21, coming into contact with the operating surfaces 20 and sliding with respect to them, exert a cutting action on the plastic material, so as to generate a corresponding through opening 22 in the capsule 4.

The capsule 4 thus obtained comprises a filtering wall 23 extending around an axis A, provided with a plurality of through openings 22. The dimensions of the openings 22, as discussed above, depend on how far the forming protrusions 18 penetrate into the respective forming recesses 16.

An internal base surface 24 is defined on the filtering wall 23, which faces the inside of the volume enclosed by the capsule 4.

On the filtering wall 23 there are formed annular projecting portions 28 which project parallel to the axis A, externally to the capsule 4, and which are arranged concentrically with respect to each other, as better shown in Figure 12. The annular projecting portions 28 have a shape corresponding to that of the forming recesses 16.

Each opening 22 has a first open zone 25 which opens onto the internal base surface 24 (as shown in Figure 11), and a second open zone 26 which opens onto a surface parallel to the axis A, that is to say onto a cylindrical surface 29 of a corresponding annular projecting portion 28, this cylindrical surface 29 facing towards a peripheral region of the filtering wall 23. Each opening 22 also comprises a third open zone 27 which opens onto a further surface parallel to the axis A, that is, onto a further cylindrical surface 30 of the annular projecting portion 28, the further cylindrical surface 30 facing towards a central zone of the filtering wall 23. In other words, the second open zone 26 and the third open zone 27 define an opening portion which extends radially through the annular projecting portions 28. Each annular projecting portion 28 comprises a crown surface 60, parallel to a plane tr asversal to axis A, which is not crossed by the openings 22.

In one embodiment, the forming protrusions 18, the forming recesses 16 and the forming ridges 17 are configured in such a way as to obtain through openings 22 which open onto the internal base surface 24 and the cylindrical surfaces 29 and do not end up on the further cylindrical surfaces 30. in this case, of each forming protrusion 18, only the operative surface 20 which is further away from a central axis of the male mold element 3 slides in contact with a corresponding further operative surface 21, so as to obtain the second open areas 26. Al on the contrary, the operating surface 20 of the aforesaid forming protrusion 20, which is closest to the aforesaid central axis, during forming, remains spaced from the further operating surface 21 facing it, so as to define an interspace which is occupied by the plastic material. In this way the third open zones are not obtained 27.

In another version, the forming protrusions 18, the forming recesses 16 and the forming reliefs 17 are configured in such a way as to obtain openings 22 which open onto the internal base surface 24 and the further cylindrical surfaces 30 and do not end up on the cylindrical surfaces 29. In this case, of each forming protrusion 18, only the operating surface 20 which is closest to the central axis of the male mold element 3 is shaped to slide in contact with a corresponding further operating surface 21, so as to obtain the third zones open 27. On the contrary, the operative surface 20 of the aforesaid forming protrusion 20, which is further away from the aforesaid central axis, during the forming, remains spaced from the further operative surface 21 facing it, so as to define a further interspace which is occupied by plastic. In this way the second open areas 26 are not obtained.

In a further version, it is possible to obtain a capsule having any combination of the through-opening configurations described above. Figures 13 and 14 schematically show a second version of apparatus 101, having many parts in common with the apparatus 1 previously described. The apparatus 101 serves to obtain a capsule 104, also shown in Figures 15 and 16, which differs from the previous capsule 4 in what will be described below.

The apparatus 101 comprises a female mold member 102 and a male mold member 103.

The male mold element 103 is provided with forming protrusions 118, which are shaped in the same way as described for the previous version of the apparatus, but which are distributed by rows or columns, that is, along rectilinear areas perpendicular to each other.

Similarly, the female mold element 102 comprises forming recesses 116 and forming reliefs 117 which, unlike the version of the apparatus described above, are not annular in shape, but are prismatic in shape and are also arranged in rows or columns, i.e. along straight lines perpendicular to each other.

Each forming protrusion 118 is provided with operative surfaces 120 opposite to each other. The operating surfaces 120 extend substantially parallel to the molding axis S.

Each forming protrusion 118 further comprises a pair of shaping surfaces 150 opposite each other and arranged transversely with respect to the operating surfaces 120.

Each forming recess 116 is provided with further operative surfaces 121. The further operative surfaces 121 are arranged substantially parallel to the molding direction S, and are adapted to cooperate with the operative surfaces 120.

Each forming recess 116 further comprises a pair of further shaping surfaces 151 opposite each other and arranged transversely with respect to the further operating surfaces 121. The further shaping surfaces 151, during forming, face the corresponding shaping surfaces 150.

In operation, each forming protrusion 118 is received in a corresponding forming recess 116.

Each shaping surface 150 is positioned so as to face a corresponding further shaping surface 151 remaining separate from the latter by a certain distance. Between each shaping surface 150 and the corresponding further shaping surface 151 a gap remains defined which is occupied by the plastic material which is progressively pushed by the forming protrusion 118.

Meanwhile, each operating surface 120 comes into contact with a corresponding further operating surface 121 and slides with respect to it, thus applying a cutting action to the plastic material such as to separate adjacent areas of plastic material to obtain an opening 122.

The capsule 104 obtained from the apparatus 101 comprises a filtering wall 123, extending around an axis A. The filtering wall 123 is provided with an internal base surface 124, facing the inside of the volume enclosed by the capsule 104, and with an external base surface 152, facing the outside of the capsule 104.

Projecting portions 153 are defined on the filtering wall 123 which project from the external base surface 152. Each projecting portion 153 comprises a first surface 154 and a second surface 155, arranged parallel to the axis A. The first surface 154 and the second surface 155 they can be parallel to each other.

Each projecting portion 153 also comprises a pair of lateral surfaces 156 each of which is transversely interposed between a first surface 154 and a second surface 155. The lateral surfaces 156, in particular, are arranged inclined with respect to the axis A, and define two respective planes which can converge on the opposite side with respect to the internal base surface 124. This allows, once the forming has been completed, to more easily disengage the capsule 104 from the female mold element 102, and in particular to extract the projecting portions 153 from the formative recesses 116.

Each opening 122 comprises a first open area 125 which opens onto the internal base surface 124, a second open area 126 which opens onto the first surface 154 and a third open area 127 which opens onto the second surface 155.

Each opening 122 is delimited by a corresponding transverse wall 160 of the projecting portion 153 extending transversely to the axis A.

All the projecting portions 153 are oriented in the same way, that is to say all the first surfaces 154 and all the second surfaces 155 are arranged parallel to the same diameter of the filtering wall 123. In one version, the projecting portions 153 can be oriented differently than to the capsule version 104 of Figures 14, 15 and 16. It is possible to provide, for example, that some projecting portions are oriented in such a way that the corresponding first surfaces and second surfaces are parallel to a first diameter, and other projecting portions are oriented in such a way that the corresponding first surfaces and second surfaces are parallel to a second diameter arranged transversely with respect to the first diameter. Figures 17 and 18 schematically show a third version of apparatus 201, shaped in a very similar way to apparatus 101 but which differs in what will be described below.

The apparatus 201 comprises a female mold element 202 and a male mold element 203, cooperating to obtain a capsule 204. The capsule 204 comprises a filtering wall 223, also shown in Figure 19.

The male mold element 203 comprises forming protrusions 218, while the female mold element 202 comprises forming recesses 216. The forming protrusions 218 and the forming recesses 216 are shaped to form in the capsule 204 projecting portions 253, similarly shaped to the projecting portions 153 of the capsule 104, and through openings 222.

Each forming protrusion 218 comprises an operating surface 220, substantially parallel to the molding direction S, a pair of first shaping surfaces 250 opposite each other, and a second shaping surface 257, opposite the operating surface 220. The operating surface 220 and the second surface shaping surfaces 257 are arranged transversely with respect to the shaping surfaces 250.

Each forming recess 216 comprises a further operating surface 221, arranged substantially parallel to the molding direction S and adapted to cooperate with a corresponding operating surface 220.

Each forming recess 216 comprises a pair of further first shaping surfaces 251, which during shaping face first shaping surfaces 250 of a corresponding forming protrusion 218. The further first shaping surfaces 251 are arranged transversely to the further operating surface 221.

Finally, each forming recess 216 comprises a further second shaping surface 258, opposite to the further operative surface 221 and adapted to cooperate with a corresponding second shaping surface 257.

During forming, when each forming protrusion 218 penetrates a corresponding forming recess 216, the first shaping surfaces 250 remain separated from the further shaping surfaces 251 by a certain distance, so as to define a gap which is filled by the plastic material.

Similarly, the second shaping surface 257 and the further second shaping surface 258 remain mutually separated by a further distance, so as to define a further gap which is occupied by the plastic material.

Each operating surface 220, on the other hand, comes into contact with a corresponding further operating surface 221.

The operating surface 220 slides on the corresponding further operating surface 221 so that a cutting action is applied to the plastic material capable of separating adjacent areas of plastic material to obtain an opening.

The capsule 204 which is obtained is provided with through openings 222 which differ from the through openings 122 obtained through the previous apparatus 101 in what will be described below. Each projecting portion 253 of the capsule 204 comprises a first surface 254, arranged substantially parallel to a longitudinal axis A of the capsule 204, and a second surface 255, arranged on the opposite side to the first surface 254. The second surface 255 can be arranged parallel to the first surface 254. Each opening 222 comprises a first open zone 225 (better visible in Figure 18) which opens onto an internal base surface 224 of the filter wall 223, and a second open zone 226, shown in Figure 19, which opens onto the first surface 254 of the corresponding projecting portion 253.

Each opening 222 is delimited by a corresponding transverse wall 260 of the projecting portion 253 extending transversely to the axis A.

Unlike the capsule 104, in the capsule 204 the openings 222 do not open onto the second surfaces 255. In the capsule 204, the openings 222 open only on one side of each projecting portion 253, and not on two opposite sides as in the capsule 104.

In the capsule 204 shown in Figure 19, the projecting portions 253 are all equally oriented, i.e. all the first surfaces 254 are parallel to the same diameter of the filtering part 223.

In one version, the projecting portions 253 can also be oriented differently from as shown in Figure 19. It is possible to provide, for example, that some projecting portions are oriented in such a way that the corresponding first surfaces are parallel to a diameter of the filtering wall 223, and other projecting portions are oriented in such a way that the corresponding first surfaces, in this particular case, are parallel to a further diameter arranged transversely with respect to the aforesaid diameter.

Furthermore, the projecting portions 253, in one case, may not even be parallelepiped-shaped, and may instead have the shape of a truncated pyramid.

In a further version it is possible to provide a capsule having any combination of the through-opening configurations of the capsule 104 and the capsule 204.

The capsules described above with reference to Figures 1 to 19, thanks to the fact that they are obtained by compression molding, are devoid of sprues which instead are found in known capsules obtained by injection molding. The risers are residues of plastic material that remain in the areas where the injection duct of the plastic material flows and that generate protuberances that cause an unpleasant aesthetic effect. Furthermore, such protuberances can act as trigger points for strains and ruptures in the capsules.

As an alternative to compression molding, it is possible to obtain the capsules described above by injection molding. In this case, the first forming means and the second forming means, during the injection of the plastic material, are already arranged in a forming position to define a forming cavity. When a desired quantity of plastic material has been introduced into the forming cavity, the first forming means and the second forming means are reciprocally moved in such a way that the forming protrusions and the respective forming recesses interacting with each other apply a shear force on the plastic material to separating adjacent areas of plastic material and thereby generating through openings on the filter walls. The size of the openings obtained can be modified by varying the extent of penetration of the forming protrusions with respect to the forming recesses. It is also possible to provide for the apparatuses described above, both in the field of compression molding and in the field of injection molding, an operation such as to obtain a capsule provided with through openings along the thickness of the filtering wall of the capsule, i.e. openings which extend parallel to a longitudinal axis of the capsule.

In fact, it is possible to provide portions of the first forming means and further portions of the second forming means which, in a forming position, are such as to mutually slide along a direction transverse to the longitudinal axis of the capsule, for example due to a relative rotation of the first forming means with respect to the second forming means about the longitudinal axis. The portions and further portions thus apply a shear force on the plastic material which separates adjacent areas of plastic material to generate one or more through openings on the filter wall.

Figures 29 to 31 show an apparatus 501 having some similarities with the apparatuses described above, but which differs from them in what will be described below.

The apparatus 501 is provided with a female mold member 502 and a male mold member 503.

The female mold element 502 and the male mold element 503 are mutually movable along the molding direction S and cooperate to mold, for example in the case of compression molding, a compact dose 500 of plastic material to form an object, such as a capsule. In the example shown in Figures 29 to 31, the female mold member 502 is stationary, and the male mold member 503 is movable.

The female mold element 502 comprises forming recesses 516. The male mold element 503 comprises forming protrusions 518, adapted to cooperate with the forming recesses 516. The forming protrusions 518, in the example described, are arranged in rows and columns.

Each forming protrusion 518 comprises an operating surface 520 which, in the example shown in Figures 29 to 31, is arranged parallel to the molding direction S. Each forming protrusion 518 comprises a pair of first shaping surfaces 550, arranged on opposite sides 1 ' with respect to each other and arranged transversely with respect to the operative surface 520.

Each forming protrusion 518 further comprises a second shaping surface 557 arranged on the opposite side with respect to the operative surface 520. The second shaping surface 557 is arranged transversely with respect to the first shaping surfaces 550.

In a first version, the apparatus 501 is configured to obtain a capsule 590 as shown in Figures 32 to 34.

In this version, the female mold element 502 can be shaped in a similar way to that described for the apparatus 201, with reference to Figures 17 and 18.

Each forming recess 516 has, for example, a parallelepiped or truncated pyramid shape, and is shaped to receive a respective forming protrusion 518.

Each forming recess 516 comprises a further operating surface 521 which, in the example shown in Figures 29 to 31, is arranged substantially parallel to the molding direction S and is adapted to cooperate with a corresponding operating surface 520 of a forming protrusion 518.

Each forming recess 516 further comprises further first shaping surfaces (not shown) which, during shaping, face respective first shaping surfaces 550 of a corresponding forming protrusion 518. The further first shaping surfaces are arranged transversely to the further operative surface 521.

Each forming recess 516 comprises a further second shaping surface 558, opposite to the further operative surface 521 and adapted to cooperate with a corresponding second shaping surface 557. The second shaping surface 558 can be arranged slightly inclined instead of being parallel to the further operative surface 521 In this way the extraction of the capsule 590 from the apparatus 501 at the end of the forming can be facilitated.

During forming, each forming protrusion 518 is moved along a first linear path T, parallel to the molding direction S, and subsequently along a second linear path U, transversely to the molding direction S, for example perpendicular to the latter.

In particular, along the first linear path T, each forming protrusion 518 penetrates into a corresponding forming recess 516. The first shaping surfaces 550 remain separated from the further first shaping surfaces by a certain distance, so as to define a gap which is filled by the plastic material.

Similarly, the second shaping surface 557 and the further second shaping surface 558 remain mutually separated by a further distance, so as to define a further gap which is occupied by the plastic material.

Each operating surface 520, on the other hand, comes into contact with a corresponding further operating surface 521.

The operating surface 520, along the first linear path, slides on the corresponding further operating surface 521 so that a cutting action is applied on the plastic material capable of separating adjacent areas of plastic material to obtain a through opening, in analogy to what described above for the other capsule versions.

In this way projecting portions 553 are obtained which project from an external base surface 509 of the capsule 590.

Subsequently, each forming protrusion 518 is moved along the second linear path U in such a way as to move the operating surface 520 away from the respective further operating surface 521, and in such a way as to bring the second shaping surface 557 closer to the corresponding further second shaping surface 558.

Each forming protrusion 518, while moving along the second linear path U, tends to move with it also the plastic material which is contiguous to it. In other words, the forming protrusion 518 tends to displace the projecting portion 553 with it. In this way, the areas of plastic material surrounding the opening previously obtained are deformed due to the cohesion of the plastic material itself to the forming protrusion 518. L The opening can thus be deformed so as to partially open onto a surface perpendicular to a longitudinal axis A of the capsule 590.

To ensure that the plastic material does not flow back into the empty regions that are generated in the vicinity of the opening due to the removal of the operating surface 520 from the further operating surface 521, it is possible to decrease the temperature of the plastic material, for example by means of cooling elements included in the apparatus 501. Alternatively, or also in combination with what has just been said, it is also possible to move away by a certain amount, parallel to the molding direction S, the female mold element 502 from the male mold element 503, for example, while each forming protrusion 518 moves along the second linear path U, in such a way as to increase by a certain amount the volume occupied by the plastic material and thus reduce the pressure exerted on the plastic material.

In other words, each forming protrusion 518, moving along the second linear path, deforms the respective projecting portion 553 which then assumes the final shape better visible in Figure 34.

A through opening 522 is thus obtained, delimited by an edge 540 which is contained in a surface having a position which can vary. In particular, the surface containing the edge 540 can have areas which lie substantially parallel to the longitudinal axis A of the capsule 590 and further areas arranged transversely with respect to the axis A. In one case, the further areas can be arranged perpendicular to the axis A. A portion of the edge 540 of the through opening 522 may extend over the outer base surface 509 of the capsule 590.

In a second version, the apparatus 501 is configured to obtain a capsule 604, as shown in Figures 35 to 37.

In this version of the apparatus, the forming protrusions 518, instead of being arranged in rows and columns, are arranged circumferentially on the male mold element 503, so that the operating surfaces 520 lie on radial planes passing through a longitudinal axis X of the male mold element 503.

Similarly, the forming recesses 516, in this version, are arranged circumferentially in such a way that each of them can receive a respective forming protrusion 518. Similarly to the operating surfaces 520, also the further operating surfaces 521 in this case are contained in passing radial planes for the longitudinal axis X.

During forming, each forming protrusion 518 is moved along a first linear path T, parallel to the molding direction S, as described for the capsule 590 of Figures 32, 33, and 34. Projecting portions 653 are thus obtained on which openings are provided passers whose edges, in this first phase, lie substantially on radial planes passing through a longitudinal axis A of the capsule 604.

Subsequently, the male mold element 503 is subjected to a rotation with respect to the female mold element 502, around the longitudinal axis X, of a certain amount, so that each forming protrusion 518 moves along a certain arc of circumference.

Alternatively, the female mold member 502 can be rotated relative to the male mold member 502, or both the female mold member 502 and the male mold member 503 can be rotated in opposite directions.

During the aforementioned rotation, each operating surface 520 moves away from the respective further operating surface 521, and each second shaping surface 557 approaches the corresponding further second shaping surface 558.

Each forming protrusion 518, during rotation, also tends to move the plastic material with it and to deform the projecting portion 653, in a manner similar to what has already been described with reference to the capsule 590.

Also in this case, the plastic material can be cooled, and / or the female mold element 502 can be moved away by a certain amount, parallel to the molding direction S, from the male mold element 503 as already described in previously, to prevent the plastic material from occupying the empty areas that are generated by the detachment of the operating surfaces 520 from the respective further operating surfaces 521. On the capsule 604 through openings 622 are obtained, similar to the through openings 522, but oriented circumferentially.

In particular, the through openings 622 can also face part of an external base surface 609 of the capsule 604, as better visible from Figures 35 and 37.

The capsules 590 and 604, thanks to the particular configuration of the respective through openings, allow a fluid product contained therein to pass through the respective filtering walls more easily. In fact, the fluid product can flow through the filter walls to a certain extent along directions perpendicular to the latter, and therefore is deflected to a limited extent along its path from the inside to the outside of the capsule. The apparatuses described above can be suitably configured to also produce other types of objects other than the capsules described above, for example to produce caps for sports drinks with openings, or other types of objects, for example parts of toys.

Figures 20 and 21 show an object that can be obtained by compression molding through an apparatus 301, shown in Figure 22.

The object can be a container neck 300, for example a bottle neck, or a tube neck for containing toothpaste or other products. The apparatus 301 is provided with first forming means 302 and second forming means 303 mutually movable along the molding direction S.

The first forming means comprises a female mold element 302, and the second forming means comprises a male mold element 303.

A first cavity 304 is formed in the female mold element 302, comprising a first cylindrical forming surface 305 bounded at the bottom by a lower forming surface 306. From the lower forming surface 306 a cylindrical forming portion 307 is projected which extends for a certain amount into the first cavity 304.

The cylindrical forming portion 307 is delimited at the top by an upper forming surface 308, and is laterally delimited by a lateral forming surface 309.

Recessed portions 310 are formed on the lateral forming surface 309 which, as will be described below, serve to form through openings in the container neck 300. The recessed portions 310 extend from the upper forming surface 308 towards the lower forming surface 306 of a certain amount.

The recess portions 310 are angularly distributed on the cylindrical forming portion 307 in a uniform manner, but it is possible to provide that they are distributed according to a different desired configuration.

Each recess portion 310 comprises a pair of first longitudinal operating surfaces 311, which in the illustrated example are arranged parallel to the molding direction S. The first operating surfaces 311 of each recess portion 310 can be inclined to each other so as to define planes which diverge away from a longitudinal axis of the cylindrical forming portion 307. Each recess portion 310 comprises a second operating surface 312 which connects the first operating surfaces 311 together.

The female mold member 302 comprises a first conical surface 313 which surrounds the first cavity 304.

The male mold element 303 comprises a second conical surface 314, adapted to cooperate with the first conical surface 313 to define a conical wall 315 of the container neck 300.

A cylindrical forming element 316 able to cooperate with the first cavity 304 and with the cylindrical forming portion 307 projects towards the female mold element 302 from the second conical surface 314.

The cylindrical forming element 316 is laterally delimited by a second cylindrical forming surface 317 adapted to cooperate with the first cylindrical forming surface 305 to define a cylindrical wall 318 of the container neck 300.

On the cylindrical wall 318 there can be provided externally a thread or other fastening means able to engage with a closing element, such as a cap, which can be associated with the container neck.

The cylindrical forming element 316 is delimited at the bottom by a further lower forming surface 319 adapted to cooperate with the lower forming surface 306 to define a crown wall 320 of the container neck 300.

In the cylindrical forming element 316 there is obtained a second cavity 321 adapted to receive the cylindrical forming portion 307 to define a mouth wall 329 of the container neck 300.

The second cavity 321 comprises a further lateral forming surface 323 which faces the lateral forming surface 309 during forming and is separated from the latter by a certain distance.

The further lateral forming surface 323 is delimited at the top by a further upper forming surface 324 adapted to cooperate with the upper forming surface 308 to define a transverse wall 325 of the container neck 300.

From the further upper forming surface 324 project by a certain amount towards the further lower forming surface 319 raised portions 326 extending parallel to the molding direction S.

The raised portions 326 are connected to the lateral forming surface 323 and project radially from the latter towards a central area of the second cavity 321.

Each raised portion 326 is shaped to be received in a corresponding recess portion 310.

Each raised portion 326 comprises further first operating surfaces 327 shaped to slide in contact on respective first operating surfaces 311.

Each raised portion 326 comprises a further second operating surface 328 which connects the further first operating surfaces 327 and is shaped to slide in contact on a respective second operating surface 312.

In the female mold element 302 and / or in the male mold element 303, ducts that can be passed through by a cooling fluid can be provided to cool the plastic material and allow a rapid stabilization of the shape of the container neck 300.

During forming, once a dose of plastic material, or other material as previously described, has been introduced into the apparatus 301, the female mold element 302 and the male mold element 303 are brought closer together along the molding direction S to shape the dose.

The raised portions 326 are received in the recessed portions 310. The first operating surfaces 311 and the respective further first operating surfaces 327, sliding relative to each other, apply a shear force on the plastic material such as to separate adjacent areas of the plastic material . Similarly, each second operating surface 312 and the respective further second operating surface 328, sliding relative to each other, apply a shear force on the plastic material such as to separate adjacent areas of the plastic material.

Openings 322 are thus generated which pass through the thickness of the mouth wall 329 and, in this particular case, are circumferentially distributed at a certain angular distance 1 from each other.

For each of the apparatuses described with reference to Figures 1 to 10, 13 and 14, 17 and 18, and 22, Figures 29 to 31, it is possible to provide that the respective female mold element is fixed and that the male mold element is mobile.

In one embodiment, provision is made for the male mold element to be fixed and for the female mold element to be movable. In a further embodiment it is provided that both the male mold element and the female mold element are movable relative to each other.

Figures 23 to 25 show an apparatus 401 for forming an object 400 provided with a through opening 422.

The finished object 400 is shown in Figure 28 and may comprise for example a container neck.

The apparatus 401 comprises a first mold element 402 and a second mold element 403, which can be mutually movable along a forming direction F.

The first mold element 402 comprises a first body 405 having a hole 406, for example having a cylindrical shape, which extends parallel to the forming direction F. A breaking element 407 is provided, for example having a cylindrical shape, which can slide along hole 406.

The breaking element 407 is provided at the top with a breaking surface 408, arranged transversely with respect to the forming direction F. The breaking element 407 is laterally provided with a first cylindrical surface 412.

On the rupture surface 408 there are engraved reliefs 416, which can extend radially.

The second mold element 403 comprises a second body 409, for example of annular shape. The second body 409 has a second hole 410, for example having a cylindrical shape, which extends parallel to the forming direction F and is coaxial to the first hole 406. The second hole 410 has a diameter greater than the diameter of the first hole 406. The second hole 410 is delimited by a second cylindrical surface 413.

The breaking element 407 can project a certain amount outside the first body 405 to penetrate the second hole 410. In this way, between the first cylindrical surface 412 and the second cylindrical surface 413 an annular cavity C is defined, better visible in Figure 24.

The second hole 410 houses a shaping element 411 having an annular shape, movable along the forming direction F. The shaping element 411 has a thickness T such as to allow it to slide into the annular cavity C.

An internal element 414 is provided, for example of cylindrical shape, which can slide longitudinally inside the shaping element 411. The internal element 414 is delimited at the bottom by a transverse surface 415, arranged transversely to the forming direction F.

On the transverse surface 415 there are further engraver reliefs 417, adapted to cooperate with the engraving reliefs 416.

In one version of the apparatus 401 it is possible to provide only the engraving reliefs 416, or only the further engraving reliefs 417.

During operation, a dose of plastic material to be shaped is interposed between the first mold element 402 and the second mold element 403.

The dose can have a compact shape, for example substantially spherical, or discoidal.

The first mold element 402 and the second mold element 403 are brought together to shape the dose in a first operating position D, shown in Figure 23, so as to obtain a precursor 419 (better shown in Figure 26) of the object 400. In the first operating position D the first body 405 and the second body 409 cooperate to shape a conical wall 418 of the precursor 419, while the shaping element 411 and the internal element 414 are close to the first body 405 and to the breaking element 407 to defining a transverse wall 420 of the precursor 419, on which the opening 422 is to be obtained.

The breaking element 407 and the internal element 414 are at a distance from each other corresponding to the thickness of the transverse wall 420.

In the first operative position D, the scoring projections 416, and the further scoring projections 417 cooperate to generate on the transverse wall 420 lines of intended separation 421 which facilitate the breaking of the transverse wall 420.

Subsequently, the breaking element 407, the internal element 414 and the shaping element 411 are positioned in a second operating position E, shown in Figure 24. To reach the second operating position E, the internal element 414 and the shaping element 411 are moved away from the first body 405. The breaking element 407 is pushed against the transversal wall 420 just formed and towards the inside of the second hole 410. The breaking element 407 breaks the transversal wall 420, thanks to the aid of the intended separation lines 421, and generates the opening 422 and wall portions 423 which extend around the opening 422 and parallel to the forming direction F. The precursor is thereby transformed into the object shown in Figure 27.

In the second operative position E the wall portions 423 are interposed between the first cylindrical surface 412 of the rupture element 407, and the second cylindrical surface 413 of the second body 409. The wall portions 423 therefore extend into the annular cavity C.

Subsequently, a third operative position G shown in Figure 25 is reached, in which the shaping element 411 is moved towards the first body 405 and made to penetrate into the annular cavity C to act on the wall portions 423. The shaping element 411 shapes the wall portions 423 in such a way as to obtain from them an annular edge 424 which surrounds the opening 422.

Before the apparatus 401 reaches the second operating position E, or before it reaches the third operating position G, the precursor can be heated, for example by ultrasound, so as to be better workable by the apparatus 401.

After reaching the third operative position G, the first mold element 402 and the second mold element 403 are disengaged from each other to allow the obtained object 400 to be moved away from them.

In one embodiment, the dose instead of being of plastic material can be of another material, for example a mixture of at least one metallic material and a plasticizer substance. The metallic material may comprise aluminum. The metal material can be powdered and the plasticizer substance acts as a binder and provides plasticity to the metal material.

In any case, whatever the metallic material, the object 400, once formed, can be cooled and subjected to a treatment to eliminate the plasticizing substance, for example to a debinding treatment. Subsequently, the object 400 can be subjected to a heat treatment such as sintering or compaction.

In another version, it is possible to generate the object 400 starting from a precursor already obtained previously from another apparatus, for example obtained by compression or injection molding.

Thus, the apparatus 401 can operate according to the steps described with reference to Figure 24 (second operative position E) and to Figure 25 (third operative position G). In such a case, the precursor can be heated to a temperature such that it can be processed by the apparatus 401.

In particular, before the E and G phases, the precursor can be heated for example by ultrasound. In one case, it is possible to foresee that the precursor, before being processed by the apparatus 401, is already provided with lines of intended separation. In another case, the lines of understanding separation are generated on that precursor by the apparatus 401.

Claims (1)

CLAIMS 1. Apparatus for forming an object (4; 104; 204; 300; 590; 604) having at least one through opening (22; 122; 222; 322; 522; 622), comprising first forming means (2; 102; 202; 302; 502) and second forming means (3; 103; 203; 303; 503) mutually cooperating to obtain said object (4; 104; 204; 300; 590; 604) from a material in a forming position, characterized from the fact that a first portion (16; 116; 216; 310; 516) of said first forming means (2; 102; 202; 302; 502), and a second portion (18; 118; 218; 326; 518) of said second forming means (3; 103; 203; 303; 503) are mutually sliding in said forming position, so as to apply on said material a shear force which separates adjacent areas of said material to generate said at least one through opening ( 22; 122; 222; 322; 522; 622). 2. Apparatus according to claim 1, wherein said first portion (16; 116; 216; 310; 516) and said second portion (18; 118; 218; 326; 518) are shaped in such a way as to move said adjacent areas one with respect to the other to create in said material a discontinuity defining said at least one through opening (22; 122; 222; 322; 522; 622). 3. Apparatus according to claim 1 or 2, wherein said first forming means (2; 102; 202; 302; 502) and said second forming means (3; 103; 203; 303; 503) are mutually movable along a direction of molding (S) to reach said forming position in which said first forming means (2; 102; 202; 302; 502) and said second forming means (3; 103; 203; 303; 503) interact to form said object (4 ; 104; 204; 300; 590; 604). 4. Apparatus according to claim 3, wherein said first portion (16; 116; 216; 310; 516) and said second portion (18; 118; 218; 326; 518) are mutually sliding in said forming position parallel to said direction of forming (S), so as to apply said shear stress to said material. 5. Apparatus according to claim 3 or 4, wherein said first portion (16; 116; 216; 516) and said second portion (18; 118; 218; 518) are mutually sliding transversely to said molding direction (S) in said forming position, so as to apply said shear stress to said material. 6. Apparatus according to one of claims 1 to 5, wherein said first forming means (2; 502) and said second forming means (3; 503) can rotate relative to each other about an axis of rotation, so that said first portion (16; 516) and said second portion (18; 518) can slide relative to each other to apply said shear stress to said material. 7. Apparatus according to one of the preceding claims, wherein said second portion (18; 118; 218; 518) comprises operating surfaces (20; 120; 220; 327; 520) adapted to cooperate with said first portion (16; 116; 216 ; 516). 8. Apparatus according to claim 7, wherein said first portion (16; 116; 216; 516) comprises further operating surfaces (21; 121; 221; 311; 521) adapted to cooperate with said operating surfaces (20; 120; 220 ; 327; 520) to apply said shear stress on said material. 9. Apparatus according to claim 8, wherein in said forming position said operating surfaces (20; 120; 220; 327; 520) and said further operating surfaces (21; 121; 221; 311; 521) are mutually sliding, to contact with each other. 10. Apparatus according to claim 8 or 9, when claim 7 depends on claim 3 or one of claims 4 to 6 when dependent on claim 3, wherein said operating surfaces (20; 120; 220; 327; 520) and said further operating surfaces (21; 121; 221; 311; 521) are mutually sliding parallel to said molding direction (S). 11. Apparatus according to one of the preceding claims, wherein said first portion comprises forming recesses (16; 116; 216; 310; 516) and said second portion comprises forming protrusions (18; 118; 218; 326; 518), shaped to be received in said forming recesses (16; 116; 216; 310; 516). Apparatus according to claim 11, when dependent on one of claims 7 to 10, wherein said operating surfaces (20; 120; 220; 327; 520) are arranged on said forming protrusions (18; 118; 218; 326; 518). 13. Apparatus according to claim 11 or 12, when claim 11 depends on one of claims 8 to 10, wherein said further operating surfaces (21; 121; 221; 311; 521) partially delimit said forming recesses (16; 116) ; 216; 310; 516). Apparatus according to one of claims 11 to 13, wherein said forming protrusions (18; 118; 218; 326; 518) are prism-shaped. 15. Apparatus according to claim 14, wherein said forming protrusions (18; 118; 218; 326; 518) are shaped like a parallelepiped. 16. Apparatus according to one of claims 11 to 15, wherein said forming protrusions (18; 118; 218; 518) comprise shaping surfaces (150; 250; 550) arranged transversely to said operating surfaces (20; 120; 220; 520 ). 17. Apparatus according to claim 16, wherein said shaping surfaces (150; 250; 550) are convergent to each other. 18. Apparatus according to one of claims 11 to 17, wherein said forming protrusions (18) are distributed along circular zones of said second forming means (3). 19. Apparatus according to claim 18, wherein said forming protrusions (18) are angularly distributed uniformly. 20. Apparatus according to claim 19 or 20, in which said circular areas are concentric with each other. 21. Apparatus according to one of claims 11 to 20, wherein said operating surfaces (20) extend circumferentially on said second forming means (3). 22. Apparatus according to one of claims 11 to 21, wherein said operating surfaces (20) are arranged parallel to a longitudinal axis of said second forming means (3). 23. Apparatus according to one of claims 11 to 22, wherein said forming recesses (16) have an annular shape. 24. Apparatus according to claim 23, wherein said forming recesses (16) are concentric with each other. 25. Apparatus according to one of claims 11 to 24, wherein said further operating surfaces (21) are cylindrical. 26. Apparatus according to one of claims 11 to 25, wherein said further operating surfaces (21) are arranged coaxially to a further longitudinal axis of said second first forming means (2). 27. Apparatus according to one of claims 11 to 17, wherein said forming protrusions (118; 218; 518) are linearly distributed on said second forming means (103; 203; 503). 28. Apparatus according to claim 27, wherein said forming protrusions (118; 218; 518) are distributed by rows and columns. 29. Apparatus according to claim 27 or 28, wherein said forming protrusions (118; 218; 518) are uniformly spaced from each other. 30. Apparatus according to one of claims 27 to 29, wherein said operating surfaces (120; 220; 520) are arranged parallel to a longitudinal axis of said second forming means (103; 203; 503). 31. Apparatus according to one of claims 27 to 30, wherein said forming recesses (116; 216; 516) are linearly distributed on said first forming means (102; 202; 502). 32. Apparatus according to claim 30, wherein said forming recesses (116; 216; 516) are distributed by rows and columns. 33. Apparatus according to one of claims 27 to 32, wherein said forming recesses (116; 216; 516) are uniformly spaced from each other. 34. Apparatus according to one of claims 27 to 33, wherein said operating surfaces (120; 220; 520) are arranged on planes parallel to a longitudinal axis of said second forming means (103; 203; 503). 35. Apparatus according to claim 34, wherein said planes are parallel to each other. 36. Apparatus according to one of claims 27 to 35, wherein each forming recess (116; 216; 516) comprises further shaping surfaces (151; 251) adapted to cooperate with said shaping surfaces (150; 250; 550). 37. Apparatus according to one of claims 11 to 36, wherein each forming protrusion (18; 118) comprises a pair of operating surfaces (20; 120) opposite each other. 38. Apparatus according to one of claims 11 to 37, wherein each forming recess (16; 116) comprises a pair of further operating surfaces (21; 121) opposite each other. 39. Apparatus according to one of claims 27 to 36, wherein each forming protrusion (218) comprises only one operating surface (220). Apparatus according to claim 39, wherein each forming protrusion comprises a forming surface (257) disposed on the opposite side to said operating surface (220). 41. Apparatus according to claim 40, wherein said forming surface (257) is inclined with respect to said operating surface (220). 42. Apparatus according to claim 40, wherein said forming surface (257) is parallel to said working surface (220). 43. Apparatus according to one of claims 39 to 42, wherein each forming recess (216) comprises only one further operating surface (221). Apparatus according to claim 43, wherein each forming recess (216) comprises a further forming surface (258) disposed on the opposite side to said further operating surface (221). 45. Apparatus according to claim 44, wherein said further forming surface (258) is inclined with respect to said further operative surface (221). 46. Apparatus according to claim 44, wherein said further forming surface (258) is parallel to said further operative surface (221). 47. Apparatus according to one of claims 11 to 46, wherein each forming protrusion (18; 118; 218; 326; 518) is delimited transversely by a forming base surface. 48. Apparatus according to claim 47, wherein each forming recess (16; 116; 216; 310) is delimited by a forming bottom surface able to face said forming base surface. 49. Apparatus according to one of claims 11 to 15, wherein said first forming means (302) comprise a first cavity (304). 50. Apparatus according to claim 49, wherein said first cavity (304) is laterally delimited by a first forming surface (305). 51. Apparatus according to claim 50, wherein said first forming surface (305) is cylindrical. 52. Apparatus according to claim 50 or 51, and comprising a lower forming surface (306) which demarcates said first forming surface (305) at the bottom. 53. Apparatus according to one of claims 49 to 52, wherein said forming recesses (310) are formed on a forming portion (307) extending inside said first cavity (304). 54. Apparatus according to claim 53 when dependent on claim 52, wherein said forming portion (307) projects from said lower forming surface (306) by a certain amount towards said second forming means (303). 55. Apparatus according to claim 53 or 54, wherein said forming portion (307) is delimited transversely by an upper forming surface (308), and laterally by a lateral forming surface (309). 56. Apparatus according to claim 55, wherein said recessed portions (310) are formed on said lateral forming surface (309). 57. Apparatus according to claim 55, or 56, when claim 53 depends on claim 52, wherein said recessed portions (310) extend a certain amount from said upper forming surface (308) towards said lower forming surface (306 ). 58. Apparatus according to one of claims 53 to 57, wherein said recess portions (310) are angularly distributed on said forming portion (307) in a uniform way. 59. Apparatus according to one of claims 49 to 58, wherein each recessed portion (310) comprises three operating surfaces (311, 312). 60. Apparatus according to claim 59, wherein said operating surfaces comprise a pair of first operating surfaces (311) facing each other and a second operating surface (312) arranged transversely to said first operating surfaces (311). 61. Apparatus according to claim 60, wherein said first operating surfaces (311) converge to each other towards a central area of said first forming means (302). 62. Apparatus according to one of claims 49 to 61, wherein said first forming means (302) comprise a first conical surface (313) surrounding said first cavity (304). 63. Apparatus according to claim 62, wherein said second forming means (303) comprise a second conical surface (314) adapted to cooperate with said first conical surface (313) to define a conical wall (315) of said object (300) . 64. Apparatus according to claim 63, wherein said second forming means (303) comprise a forming element (316) projecting from said second conical surface (314) towards said first forming means (302) and adapted to be received in said first cavity (304). 65. Apparatus according to claim 64, wherein said forming element (316) is substantially cylindrical. 66. Apparatus according to claim 64 or 65, when claim 62 depends on one of claims 50 to 52 or one of claims 53 to 61, when dependent on one of claims 50 to 52, wherein said forming element ( 316) comprises a second forming surface (317) adapted to cooperate with said first cylindrical surface (305) to define a cylindrical wall (318) of said object (300). 67. Apparatus according to one of claims 64 to 66, when claim 62 depends on claim 52 or one of claims 53 to 61, when dependent on claim 52, wherein said forming element (316) is delimited transversely by a further lower forming surface (319) adapted to cooperate with said lower forming surface (306) to define a crown wall (320) of said object (300). 68. Apparatus according to one of claims 64 to 67, when claim 62 depends on one of claims 53 to 58 or one of claims 59 to 61 when dependent on one of claims 53 to 58, and comprising a second cavity (321) obtained in said forming element (316) and adapted to receive said forming portion (307) to define a mouth wall (329) of said object (300). 69. Apparatus according to claim 68, when claim 62 depends on one of claims 55 to 57 or on one of claims 58 to 61 when dependent on one of claims 55 to 57, wherein said second cavity (321) comprises a further lateral forming surface (323) adapted to cooperate with said lateral forming surface (309). 70. Apparatus according to claim 69, wherein said further lateral forming surface (323) is delimited transversely by a further upper forming surface (324) adapted to cooperate with said upper forming surface (308) to define a transverse wall (325) of said object (300). 71. Apparatus according to claim 70, wherein said forming protrusions (326) project from said further upper forming surface (324) by a certain amount towards said first forming means (302). 72. Apparatus according to claim 71, wherein said forming protrusions (326) are connected to said lateral forming surface (323) and radically project towards a central area of said second forming means (303). 73. Apparatus according to claim 60 or 61, or according to one of claims 62 to 72, when dependent on claim 60 or 61, wherein each forming protrusion (326) comprises two further first operating surfaces (327) shaped to slide in contact with respective first operational areas (311). 74. Apparatus according to claim 73, wherein each forming protrusion (326) comprises a further second operating surface (328) which connects said further first operating surfaces (327) and which is shaped to slide in contact with respect to a respective second operating surface (312) 75. Apparatus according to one of claims 49 to 74, and further comprising cooling circuit means for cooling said material and for stabilizing the shape of said object (300). 76. Apparatus according to one of claims 49 to 75, wherein said object is a container neck (300). 77. Apparatus according to one of claims 1 to 48, wherein said object is a capsule (4; 104; 204; 590; 604) 78. Apparatus according to one of the preceding claims, wherein said material is selected from a group comprising: plastic material, a mixture of at least one metallic material and a plasticizer. 79. Apparatus according to one of the preceding claims, wherein said first forming means comprise a female mold element (2; 102; 202; 302; 502) and said second forming means comprise a male mold element (3; 103; 203; 303; 503). 80. Apparatus according to one of the preceding claims, wherein said first forming means (2; 102; 202; 302; 502) and said second forming means (3; 103; 203; 303; 503) are configured to form said object (4 ; 104; 204; 300; 590; 604) by compression molding. 81. Apparatus according to one of claims 1 to 79, wherein said first forming means (2; 102; 202; 302; 502) and said second forming means (3; 103; 203; 303; 503) are configured to form said object (4; 104; 204; 300; 590; 604) by injection molding. 82. A method comprising the steps of: shaping a material by means of first forming means (2; 102; 202; 302; 502) and second forming means (3; 103; 203; 303; 503) cooperating with each other to form an object (4 ; 104; 204; 300; 590; 604). forming on said object (4; 104; 204; 300; 590; 604) at least one through opening (22; 122; 222; 322; 522; 622), characterized in that said forming comprises moving said first forming means (2 ; 102; 202; 302; 502) and said second forming means (3; 103; 203; 303; 503) with respect to each other so as to apply on said material a shear force which separates adjacent areas of said material to generate said at least one through opening (22; 122; 222; 322; 522; 622). 83. A method according to claim 82, wherein said moving comprises moving said adjacent areas relative to each other to create a discontinuity in said material defining said at least one through opening (22; 122; 222; 322; 522; 622). 84. A method according to claim 82 or 83, and comprising reciprocally approaching said first forming means (2; 102; 202; 302; 502) and said second forming means (3; 103; 203; 303; 503) along a molding direction (S). 85. Method according to one of claims 82 to 84, wherein said moving comprises mutually sliding, in a forming position, a first portion (16; 116; 216; 310; 516) of said first forming means (2; 102 ; 202; 302; 502) and a second portion (18; 118; 218; 326; 518) of said second forming means (3; 103; 203; 303; 503) to obtain said at least one through opening (22; 122 ; 222; 322; 522; 622). A method according to claim 85, when dependent on claim 84, wherein said sliding comprises mutually sliding said first portion (16; 116; 216; 310; 516) and said second portion (18; 118; 218; 326; 518) parallel to said molding direction (S). A method according to claim 85 or 86, wherein said sliding comprises mutually sliding said first portion (16; 116; 216; 310; 516) and said second portion (18; 118; 218; 326; 518) transversely to said molding direction (S) to modify said at least one through opening (22; 122; 222; 322; 522; 622). 88. Method according to one of claims 82 to 87, wherein said moving comprises mutually rotating said first forming means (2; 102; 202; 302; 502) and said second forming means (3; 103; 203; 303; 503) around an axis of rotation. 89. Method according to claim 88, when dependent on one of claims 85 to 87, wherein said rotation is such as to slide said first portion (16; 516) and said second portion (18; 518) relative to each other. the other about said axis of rotation. 90. Method according to one of claims 85 to 87, or according to claim 88 or 90, when dependent on one of claims 85 to 87, wherein said movement comprises bringing operating surfaces (20; 120; 220; 327) into contact; 520) of said second portion (18; 118; 218; 518) with further operating surfaces (21; 121; 221; 311; 521) of said first portion (16; 116; 216; 516). 91. A method according to one of claims 82 to 90, and further comprising cooling said material to stabilize the shape of said object (4; 104; 204; 300; 590; 604). 92. Method according to one of claims 82 to 91, wherein said object is a capsule (4; 104; 204; 590; 604). 93. Method according to one of claims 82 to 91, wherein said object is a container neck (300). 94. Method according to one of claims 82 to 93, wherein said material is selected from a group comprising: plastic material, a mixture of at least one metallic material and a plasticizer. 95. Method according to one of claims 82 to 94, wherein said shaping comprises compression molding said material. A method according to one of claims 82 to 94, wherein said shaping comprises injection molding said material. 97. Method according to one of claims 82 to 94, wherein said shaping comprises thermoforming said material, having the form of a sheet. 98. Capsule suitable for containing a powder substance for preparing a beverage, comprising a side wall (8, 12) extending around an axis (A) and a filtering wall (23; 123; 223) provided with a plurality of through openings (22; 122; 222; 522; 622), characterized in that the through openings (22; 122; 222; 522; 622) of said plurality of through openings open onto at least one surface substantially parallel to said axis (A). 99. Capsule according to claim 98, wherein said through openings (22; 122; 222; 522; 622) also open onto an internal base surface (24; 124; 224) of said filter wall (23; 123; 223) . 100 Capsule according to claim 98 or 99, in which said through openings (22; 122; 222; 522; 622) are formed on projecting portions (28, 153, 253, 553, 653) projecting from said filtering wall (23; 123 ; 223). 101 Capsule according to claim 100, wherein said projecting portions (28, 153, 253, 553, 653) project from an external base surface (9; 152; 509; 609) of said filter wall (23; 123; 223) ). 102 Capsule according to claim 100 or 101, wherein said projecting portions (28) extend along a closed path on said filter wall (23). 103 Capsule according to one of claims 100 to 102, in which said projecting portions (28) have an annular shape. 104 Capsule according to one of claims 100 to 103, wherein each projecting portion (28) comprises a cylindrical surface (29) onto which said openings (22), said cylindrical surface (29) extending around said axis (A). 105 Capsule according to claim 104, wherein each projecting portion (28) comprises a further cylindrical surface (30) arranged on the opposite side to said cylindrical surface (29), onto which said openings (22) open. 106 Capsule according to claim 105, wherein said further cylindrical surface (30) is closer to said axis (A) than said cylindrical surface (29). 107 Capsule according to one of claims 100 to 106, in which said through openings (22) are uniformly distributed along said projecting portions (28). 108 Capsule according to claim 101, or according to one of claims 102 to 107, when dependent on claim 101, in which each projecting portion (28) is delimited by a crown surface (60) disposed at a certain distance from said surface of external base (9). 109 Capsule according to one of claims 100 to 108, in which said projecting portions (28) are arranged concentrically with respect to each other. 110 Capsule according to claim 100 or 101, wherein each projecting portion (153, 253, 553, 653) is shaped like a hollow prism. 111 Capsule according to claim 110, in which each projecting portion (153, 253, 553, 653) is shaped like a hollow parallelepiped. 112 Capsule according to claim 100 or 101, or 110 or 111, wherein each projecting portion (153, 253, 553, 653) comprises a pair of lateral surfaces (156) arranged on opposite sides. 113 Capsule according to claim 112, wherein said lateral surfaces (156) are mutually inclined and converging towards the outside of said capsule (104; 204; 590; 604). 114 Capsule according to one of claims 110 to 113, wherein each projecting portion (153, 253, 553, 653) comprises a first surface (154; 254) onto which a respective opening (122; 222) leads. 115 Capsule according to claim 114, wherein said first surface (154; 254) is parallel to said axis (A). 116 Capsule according to claim 115, wherein said projecting portions (153; 253, 553) are positioned in such a way that the respective first surfaces (154; 254) are oriented in the same way. 117 Capsule according to one of claims 114 to 116, wherein each projecting portion (153, 253, 553, 653) comprises a second surface (155; 255) arranged on the opposite side to said first surface (154; 254). 118 Capsule according to claim 117, wherein a respective through opening (122) opens onto said second surface (155). 119 Capsule according to claim 117, wherein said second surface (255) is not crossed by the respective opening (222). 120 Capsule according to one of claims 110 to 119, in which said projecting portions (153, 253, 553, 653) are uniformly spaced from each other. 121 Capsule according to one of claims 110 to 120, in which said projecting portions (153, 253, 553, 653) are linearly distributed on said filter wall (123, 223). 122 Capsule according to claim 121, in which said projecting portions (153, 253, 553, 653) are distributed by rows and columns. 123 Capsule according to one of claims 110 to 120, in which said projecting portions (653) are distributed along circular areas of said filter wall. 124. Capsule according to claim 123, in which said projecting portions (653) are angularly distributed in a uniform manner. 125.Capsule according to one of claims 98 to 101, or according to one of claims 110 to 124, in which said through openings (522; 622) also open onto a surface transverse to said axis (A). 126 Capsule according to claim 125, wherein said transverse surface lies on said filter wall. 127 Capsule according to one of claims 98 to 126, and made of plastic material. 128 Capsule according to one of claims 98 to 127, obtained by compression molding. 129 Capsule according to one of claims 98 to 128, obtained by injection molding. 130 Capsule suitable for containing a powder substance for preparing a beverage, comprising a side wall (8, 12) extending around an axis (A) and a filtering wall (23; 123; 223) provided with a plurality of through openings ( 22; 122; 222; 522; 622), characterized in that said capsule (4; 104; 204; 590; 604) is obtained by compression molding. 131. Apparatus for forming an object (400) having a through opening (422), comprising breaking means (407, 414) for breaking a wall of a precursor (419) of said object (400), so as to obtain wall portions ( 423) arranged around said through opening (422), said apparatus (401) further comprising shaping means (411) for shaping said wall portions (423) so as to define an edge area (424) of said through opening (422 ). 132. Apparatus according to claim 131, and further comprising a first mold element (402) and a second mold element (403), mutually movable along a direction (F). 133. Apparatus according to claim 132, wherein a hole (406) extending parallel to said direction (F) is formed on said first mold element (402), along which said breaking means (407, 414) slide. 134. Apparatus according to claim 133, wherein said hole (406) is cylindrical. 135. Apparatus according to one of claims 131 to 134, wherein said breaking means (407, 414) are provided with a breaking surface (408, 415). 136. Apparatus according to claim 135, wherein said rupture surface (408, 415) extends transversely to said direction (F). 137. Apparatus according to one of claims 131 to 136, and further comprising incising reliefs (416, 417) made on said breaking means (407, 414) and suitable for promoting the breaking of said precursor wall (419). 138. Apparatus according to claim 137 when dependent on claim 135 or 136, in which said engraving reliefs (416, 417) are formed on said breaking surface (408, 415). 139. Apparatus according to claim 137 or 138, wherein said incising ridges (416, 417) extend radially on said breaking means (407, 414). 140. Apparatus according to claim 133 or 134, or according to one of claims 135 to 139 when dependent on claim 133 or 134, in which a further hole (410) is made on said second mold element (403) along which said breaking means (407, 414). 141. Apparatus according to claim 140, wherein said further hole (410) is arranged coaxially with respect to said hole (406). 142. Apparatus according to claim 140 or 141, wherein said hole (406) has a smaller cross section than said further hole (410). 143. Apparatus according to one of claims 140 to 142, wherein said breaking means comprise a first breaking element (407) and a second breaking element (414) sliding respectively in said hole (406) and in said further hole (410) . 144. Apparatus according to claim 143, wherein said first rupture element (407) can partially penetrate said further hole (410) so as to define with said second mold element (403) an annular cavity (C) adapted to receive said portions of the wall (423). 145. Apparatus according to claim 144, wherein said shaping means (411) are shaped in such a way as to slide inside said annular cavity (C) to shape said wall portions (423). 146 Apparatus according to claim 145, wherein said shaping means (411) are cylindrical in shape. 147 Apparatus according to claim 146, wherein said shaping means (411) have a thickness (T) such as to obtain said edge area (424). 148 Apparatus according to one of claims 131 to 147, wherein said object is a container neck (400). 149 Method of forming an object (400) having a through opening (422), comprising the steps of: - providing a precursor (419) of said object (400), said precursor (419) having a wall (420) in a position in which it is intended to obtain said through opening (422); breaking said wall (420) to obtain wall portions (423) arranged around said through opening (422); - shaping said wall portions (423) to define an edge area (424) of said through opening (422). 150 A method according to claim 149, wherein said breaking comprises etching said wall (420) to obtain thereon lines of intended separation (421). 151 A method according to claim 149 or 150, wherein said breaking comprises exerting a thrust on said wall (423). 152 Method according to one of claims 149 to 151, wherein said break comprises arranging said wall portions (423) parallel to a longitudinal axis of said object (400). 153 Method according to one of claims 149 to 152, and further comprising heating said precursor (419). 154 The method of claim 153 wherein said heating is provided prior to said shaping. A method according to claim 153, or 154, wherein said heating is provided prior to said breaking. 156 A method according to one of claims 153 to 155, wherein said heating comprises heating by ultrasound. 157 Method according to one of claims 149 to 156, wherein said supply comprises printing a dose from a material to obtain said precursor (419). The method of claim 157, wherein said printing comprises compression molding said material. 159 A method according to claim 157, wherein said molding comprises injection molding said material. 160 Method according to one of claims 157 to 159, wherein said material is selected from a group comprising: plastic material, a mixture of at least one metallic material and a plasticizer. 161 Method according to one of claims 149 to 160, and comprising subjecting said object (400) to a debinding treatment. 162 Method according to one of claims 149 to 161, and further comprising subjecting said object (400) to sintering or compacting. 163. Method according to one of claims 149 to 162, wherein said object is a container neck (400). Method according to one of claims 149 to 163, wherein said shaping comprises deforming said wall portions (423) so as to obtain therefrom a substantially flat edge region (424). 165 Method according to claim 164, wherein said deforming comprises leveling said wall portions (423) .166 Method according to claim 164 or 165, wherein said deforming comprises moving the material which forms said wall portions (423) from more high arranged on the top of said wall portions (423) with lower areas interposed between two adjacent wall portions (423).