Molding method and molding unit for molding an object

Abstract

One method includes: - an insertion step for inserting a preform (2) made of a moldable material between a concave half-mold (6; 106; 206) and a convex half-mold (7; 107; 207); - a forming step for pressing the preform (2) between the convex half-mold (7; 107; 207) and the concave half-mold (6; 107; 207) by moving at least one half-mold selected from the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207) along a forming direction (D) toward another half-mold selected from the convex half-mold (7; 107; 207) and the concave half-mold (6; 106; 206) to form an object (3). Furthermore, a locking step is provided before the end of the molding step to lock a portion of the preform (2) between the concave half-die (6; 106; 206) and the convex half-die (7; 107; 207). The half-die selected from the concave half-die (6; 106; 206) and the convex half-die (7; 107; 207) includes a movable central portion (9; 109; 209) that is displaceable between an advancing position (PA) and a retracted position (PR). The movable central portion (9; 109; 209) is in the advancing position (PA) during the locking step and is in the retracted position (PR) at least at the end of the molding step.

Description

Technical Field

[0001] This invention relates to a molding method and molding unit for forming an object by pressing a quantitative preform of a moldable material. Background Technology

[0002] The moldable material used to make objects can be a natural fiber-based material, such as a cellulose-based material, in the form of an air-laid web (essentially dry or wet), a pile, aggregated powder, or the like. The moldable material may include a limited amount of synthetic polymer material fibers, blended with natural fibers.

[0003] Alternatively, the moldable material used to make the object can be a synthetic polymer material, such as polyethylene, polyethylene terephthalate, polypropylene, polyvinyl alcohol, or other materials.

[0004] The moldable material used to make this preform can be a multilayer material obtained by combining layers of similar materials or layers of different materials. In the latter case, one or more layers of natural fibrous-based material (e.g., cellulose) can be combined with one or more layers of synthetic polymer material (e.g., in the form of a film or fiber).

[0005] The object formed by the molding method and molding unit according to the invention can be a packaging component, specifically having a concave shape, such as a cap, capsule, container, or preform. However, this condition is not required, and other types of objects can be formed using the molding method and molding unit according to the invention.

[0006] To form an object from a moldable material by pressing, it is known to position a metered preform of the moldable material between a convex half and a concave half of a molding unit. When the metered preform is released between the convex and concave half, these half-die positions are spaced apart. Then, the convex and concave half-die move toward each other to gradually deform and compress the metered preform until the desired object is obtained.

[0007] One drawback of existing forming units is that when the convex and concave mold halves move toward each other along the forming direction to compress the preform, the preform may move laterally in the forming direction in an undesirable manner. In this way, the preform may be positioned off-center between the convex and concave mold halves, which compromises the quality of the formed object.

[0008] Another drawback of existing molding units is that, in some cases, excessive stretching of certain portions of the moldable material preform may occur when the moldable material forming the preform deforms between the convex and concave mold halves. This excessive stretching may result in insufficient thickness in some areas of the formed object, or even cause breakage at some points in the formed object. US 3305158 discloses a method for forming a hollow container by thermoforming a preform made of an oriented synthetic plastic material. After heating the preform to its orientation temperature, the peripheral portion of the preform is locked in a mold cavity. Then, the central portion of the preform is displaced relative to the locked peripheral portion toward the interior of the mold cavity. Simultaneously, pressure is applied to both surfaces of the central portion to induce lateral flow of the synthetic plastic material in the central portion and form a sidewall of the container formed between the locked peripheral portion and the displaced central portion.

[0009] The preform is locked at its periphery between a lip extending from the base of the mold and two movable parting blocks that form the outer surface of the container sidewall.

[0010] EP 2828171 discloses a method for forming a paper pallet by deep drawing. The pallet includes a bottom and sidewalls extending upward around the bottom. The sidewalls of the pallet are shaped to form a plurality of circumferential steps.

[0011] The tray disclosed in EP 2828171 is formed in an apparatus including an upper forming tool and a lower forming tool. Each forming tool is provided with a concentric frame that allows steps to be formed in the sidewalls.

[0012] The pallet is formed from a cardboard blank or roll, which is locked at its peripheral edges between the upper and lower forming tools at the start of the forming step.

[0013] The drawback of the method disclosed in US 3305158 is that, by firmly locking the preform at its peripheral edges, the preform material may fracture as it deforms to form the sidewalls of the container. That is, the sidewalls of the container may tear because the material forming the container is significantly stretched while its peripheral and central portions are locked.

[0014] This drawback is exacerbated if the preform is made of natural fiber-based materials instead of oriented synthetic plastics, as natural fiber-based materials are less deformable and more easily torn than oriented synthetic polymers.

[0015] Similar drawbacks may occur in the method disclosed in EP 2828171. Summary of the Invention

[0016] One object of the present invention is to improve the molding method and molding unit for forming objects by pressing a quantitative preform made of natural fiber-based materials and / or synthetic polymer materials.

[0017] Another objective is to provide a molding method and molding unit for forming an object by pressing a quantitative blank, wherein the position of the quantitative blank between the convex and concave half-die of the molding unit can be better controlled.

[0018] Another objective is to provide a molding method and molding unit for forming an object by pressing a quantitative blank, wherein the risk of the quantitative blank being positioned off-center is minimized when the convex and concave half-die moves toward each other.

[0019] Another objective is to provide a molding method and molding unit by means of which high-quality objects can be formed by pressing a quantitative preform made of natural fiber-based materials and / or synthetic polymer materials.

[0020] Another objective is to prevent the preform of the moldable material from becoming too thin or even tearing when it deforms between the convex and concave half of the molding unit.

[0021] In a first aspect of the present invention, a method is provided, comprising the following steps: - Insertion step: Insert a preform made of moldable material between the concave half mold and the convex half mold; - A forming step, wherein an object is formed by moving at least one half of a die selected from a concave half of a die and a convex half of a die along a forming direction toward another half of a die selected from a convex half of a die and a concave half of a die, thereby pressing a quantitative blank between the convex half of a die and the concave half of a die. The molding step includes a locking step prior to the end of the molding step, which locks a portion of the preform between the concave and convex mold halves. The mold halves selected from the concave and convex mold halves include a movable central portion that is displaceable between an advancing position and a retracted position. The movable central portion is in the advancing position during the step of locking the portion of the preform and is in the retracted position at least at the end of the molding step.

[0022] By locking a portion of the preform, it can be held in the correct position between the convex and concave mold halves, thus preventing lateral displacement. In this way, the risk of the preform being positioned off-center before or during the molding process can be prevented or minimized. This contributes to the formation of high-quality molded objects.

[0023] The movable center portion, positioned in the forward position and then reaching the retracted position during the locking of the center portion of the billet, allows for a pre-forming of the billet. This helps prevent the billet from becoming excessively thin during the forming step, which increases the uniformity of the thickness of the formed object.

[0024] In one embodiment, during the locking step, the central portion of the quantitative blank is locked between the movable central portion arranged in the forward position and the half-die (selected from a convex half-die or a concave half-die) facing the movable central portion.

[0025] In this case, the movable center portion together with the mold half facing it has a locking function, and the movable center portion acts on the center portion of the metering blank to prevent lateral displacement of the metering blank, that is, displacement of the metering blank transverse to the forming direction.

[0026] The billet has a peripheral portion defined by its perimeter edge.

[0027] In one embodiment, during the locking step, the peripheral portion of the quantitative blank is in a free state, while the central portion of the quantitative blank is locked between the movable central portion arranged in the forward position and the half-die (selected from a convex half-die or a concave half-die) facing the movable central portion.

[0028] Allowing the peripheral portion of the preform to be free during the locking step is particularly useful when the preform is being shaped to form a concave object.

[0029] In fact, by freeing the peripheral portion of the preform, the risk of the moldable material being torn during deformation (e.g., to the lateral portion of the generated object) is reduced.

[0030] Even though the central portion of the preform is locked between the movable central portion and the half-mold facing the movable central portion, the material around the central portion still has a certain degree of freedom of movement during forming because no locking effect is provided at the peripheral portion of the preform (especially at the peripheral edge of the preform).

[0031] This prevents the material surrounding the central portion from being subjected to excessive stress that could cause it to crack.

[0032] In an alternative implementation, during the locking step, the peripheral portion of the metered blank is locked between the concave half-die and the convex half-die, while the central portion of the metered blank is supported on a movable central portion arranged in the forward position.

[0033] In this configuration, the movable center section has a support function to support the metered blank from the initial moment of the molding step, which helps to keep the metered blank in the correct position, while the peripheral portion of the metered blank is locked between the component arranged outside the movable center section and the half mold facing it to prevent lateral displacement of the metered blank.

[0034] In one embodiment, during the locking step, this portion of the metered billet is locked by clamping it between the concave half-die and the convex half-die, but has not yet reached the final compaction.

[0035] "Final compaction" indicates the degree of compression achieved at the end of the forming step in the portion of the object formed by the metered blank (i.e., the portion of the metered blank held between the convex or concave half-die during the locking step).

[0036] After the portion of the billet adjacent to the portion of the billet locked during the locking step has been deformed, that portion of the billet locked during the locking step is compressed to the final compaction degree.

[0037] In other words, during the locking step, the portion of the preform locked between the convex and concave half-die is not fully compressed.

[0038] After another part of the preform (adjacent to the locked part) has begun to deform, the portion of the preform locked between the convex and concave half-die undergoes further compression.

[0039] This avoids excessive stress inside the preform during the forming process.

[0040] In the locking step, sufficient pressure is applied to the portion of the preform locked between the convex and concave mold halves to prevent substantial lateral displacement of the preform. However, within the locked portion, the innermost moldable material of the preform still retains some mobility. Therefore, when another portion of the preform adjacent to it deforms during the molding step, the material forming the innermost layer of the preform can follow the movement of that other portion. This minimizes the risk of the moldable material tearing during molding to form the object (specifically, the sidewalls of the object).

[0041] In one embodiment, the concave half-mold has a molding cavity for shaping the outer surface of an object, the molding cavity having a bottom surface arranged transversely to the molding direction, the bottom surface being at least partially formed on a movable central portion.

[0042] Therefore, in this embodiment, the movable central portion is included in the concave half mold.

[0043] In one embodiment, the convex half-die has a punch defined by an end face that is at least partially formed on the movable portion.

[0044] In this embodiment, the movable central portion is included in the convex half-mold.

[0045] In one embodiment, a half-mold selected from concave and convex half-molds (e.g., a concave half-mold) includes a plurality of parting blocks that can move laterally in the molding direction to define a variable volume molding area.

[0046] The parting blocks can initially be positioned at a relatively large distance from each other. This also makes it possible to handle preforms of moldable material that are large in size compared to the size of the object being formed.

[0047] Furthermore, the variable volume forming region can initially have a shape very different from that of the finished object. This allows for the use of readily available, simple preforms, even for forming objects with fairly complex structures.

[0048] Providing a variable volume forming region initially larger than the volume of the object to be manufactured reduces the risk that the moldable material may interact with the convex or concave half-mold in an undesirable manner, which could compromise the quality of the formed object. Therefore, the process of inserting a fixed quantity of preform between the convex and concave half-molds can be significantly improved.

[0049] In one embodiment, the convex die includes a compensation element that can be positioned at a variable distance from the concave die to define the dimension of the object parallel to the forming direction, which varies between consecutive objects depending on the mass of the corresponding preform.

[0050] Thanks to the compensation element, it is possible to process a fixed quantity of blanks whose quality may vary within a predetermined limit, thus ensuring that high-quality objects can be produced regardless.

[0051] In one embodiment, a portion of the preform is locked between the concave and convex mold halves due to mutual movement between the facing portions of the concave and convex mold halves, the mutual movement occurring parallel to the molding direction. In a second aspect of the invention, a molding unit is provided for forming an object by pressing a preform of a moldable material, the molding unit comprising a concave mold halves and a convex mold halves, at least one half selected from the concave and convex mold halves being movable along the molding direction toward another half selected from the convex and concave mold halves to press the preform between the convex and concave mold halves, and wherein the half selected from the concave and convex mold halves includes a movable central portion that is movable parallel to the molding direction between an advancing position (for locking a portion of the preform between the movable central portion and the half facing the movable central portion (selected from the convex and concave mold halves)) and a retracted position (where an object is formed).

[0052] In a third aspect of the invention, a molding unit is provided for forming an object by pressing a metered preform of a moldable material, the molding unit comprising a concave half-mold and a convex half-mold, at least one half-mold selected from the concave half-mold and the convex half-mold being movable along a molding direction toward the other half-mold selected from the convex half-mold and the concave half-mold to press the metered preform between the convex half-mold and the concave half-mold, wherein the half-mold selected from the concave half-mold and the convex half-mold includes a movable central portion that is movable parallel to the molding direction between an advancing position (for receiving the metered preform) and a retracted position (for forming an object), and the other half-mold selected from the convex half-mold and the concave half-mold includes a locking element for locking a peripheral portion of the metered preform before the object is fully formed.

[0053] In one embodiment of the molding unit according to a second aspect or a third aspect of the invention, the half-mold selected from concave half-molds and convex half-molds includes a plurality of parting blocks that are movable laterally in the molding direction between an expansion configuration and a molding configuration to define a variable volume molding region.

[0054] In one embodiment of the molding unit according to a second or third aspect of the invention, the convex die includes a compensating element that can be positioned at a distance from the lateral surface of the molding cavity defining the concave die, the distance depending on the mass of the preform. Therefore, an object having dimensions measured along the molding direction can be formed, with the dimension increasing as the mass of the preform increases.

[0055] Due to the second and third aspects of the present invention, high-quality objects can be formed, minimizing the quantitative blank positioning error in the molding unit. Attached Figure Description

[0056] The invention can be better understood and practiced by referring to the accompanying drawings, which illustrate several exemplary and non-limiting embodiments of the invention, in which: Figure 1 It shows a schematic cross section of a forming unit for shaping an object in an open configuration, wherein a fixed amount of blank is positioned between a concave half-die and a convex half-die. Figure 2 It is similar to Figure 1 The view shows a forming unit in a subsequent configuration, where a preform is locked between a movable central portion of a concave half-die and a convex half-die. Figure 3 It is similar to Figure 1 The view is in a configuration that shapes the horizontal walls of the object; Figure 4 It is similar to Figure 1 The view is in a configuration that shapes the sidewalls of the object; Figure 5 It is similar to Figure 1 The view is in the final configuration; Figure 6 This is a schematic cross-section showing an alternative embodiment of a molding unit in an open configuration, wherein a preform is positioned between a concave half-die and a convex half-die. Figure 7 It is similar to Figure 6 The view shows a forming unit in a subsequent configuration, where a preform is locked between a movable central portion of a convex half-die and a concave half-die. Figure 8 It is similar to Figure 6 The view is in a configuration that shapes the horizontal walls of the object; Figure 9 It is similar to Figure 6 The view is in a configuration that shapes the sidewalls of the object; Figure 10 It is similar to Figure 6 The view is in the final configuration; Figure 11 This is a schematic cross-section showing another alternative embodiment of a molding unit in an open configuration, wherein a metered blank is positioned between a concave half-die and a convex half-die; Figure 12 It is similar to Figure 11 The view shows a molding unit in a subsequent configuration, where the volume of the variable volume molding region is reduced by moving multiple parting blocks; Figure 13 It is similar to Figure 11 The view shows a configuration where a fixed quantity of blank is locked between a concave half-die and a convex half-die; Figure 14 It is similar to Figure 11 The view shows the configuration of a fixed blank deformed between a concave half-die and a convex half-die; Figure 15 It is similar to Figure 11 The view is in the final configuration. Detailed Implementation

[0057] Figures 1 to 5 A molding unit 1 is shown for shaping an object 3 by pressing a preform 2 made of a moldable material.

[0058] In the example shown, the preform 2 is made of a natural fiber-based moldable material, specifically a cellulose-based material. The preform 2 may contain, for example, 80% of its weight in cellulose. The preform 2 may also contain a limited amount of synthetic polymer material fibers, blended with the natural fibers.

[0059] The preform 2 can be in an air-laid web form, that is, it is obtained from a dense natural fibrous base material, which is defibrinated in a mill to separate the fibers that make up the material. Then, an airflow is used to transport the fibers, which are then combined to form an air-laid web structure.

[0060] The preform 2 (e.g., in the case of obtaining it from an air-laid structure) is typically in a substantially dry form, in which case the water content of the preform is less than 15% by weight, for example, less than 10% by weight. However, the preform 2 may also have a higher moisture content, for example, from 5% to 80% by weight. In this case, the water present in the preform 2 originates from the fact that water is added to the air-laid structure after the fibers have been interconnected to form the air-laid structure, for example, to help solidify and shape the object obtained from the preform 2, or as a base liquid containing one or more additives. Natural fiber-based preform 2 can even be in the form of fluff or aggregated powder.

[0061] Alternatively, the moldable material used to make the object can be a synthetic polymer material.

[0062] A preform made of a multilayer material may also be used, comprising two or more layers made of similar or dissimilar materials. The multilayer material may, for example, include at least one natural fibrous base layer (e.g., a cellulose base layer) and at least one layer of synthetic polymer material in the form of a film or fiber.

[0063] The moldable material used to make a preform can be a non-extrudable material, specifically when the material contains natural fibers. In fact, such materials cannot reach the high temperatures required for extrusion without being damaged (e.g., charred).

[0064] The preform 2 initially has a substantially flat shape. For example, the preform 2 can be circular, square, rectangular, or other shapes in a planar view. If an object with a concave shape is desired, the preform 2 can have a non-flat shape, specifically a concave shape. This makes it easier to center the preform 2 in the forming unit 1 and makes the forming of the desired object easier because the shape of the preform 2 is more similar to the shape of the object compared to the case of a flat preform.

[0065] The object 3 formed by pressing the preform 2 can have a three-dimensional shape, specifically a concave shape. In the example shown, the object 3 is cup-shaped. Some examples of objects that can be made in the molding unit are containers, capsules, caps for containers, lids, preforms for containers, trays for packaging, etc.

[0066] Object 3 may have a sidewall 4, which is closed at one end by a transverse wall 5.

[0067] The molding unit 1 includes a concave half-mold 6 and a convex half-mold 7 that are opposite to each other and aligned along the molding direction D. In the example shown, the molding direction D is vertical.

[0068] At least one die selected from the concave die 6 and the convex die 7 can move along the forming direction D relative to the other die selected from the convex die 7 and the concave die 6 to press a quantitative blank 2 and form an object 3. In the example shown, the concave die 6 can move along the forming direction D to move toward or away from the convex die 7, while the convex die 7 remains in a fixed position along the forming direction D.

[0069] In an alternative embodiment, the concave mold half 6 can be fixed along the molding direction D, while the convex mold half 7 can move along the molding direction D to move toward or away from the concave mold half 6. Both the convex mold half 7 and the concave mold half 6 can also be moved along the molding direction D.

[0070] The concave half mold 6 and / or the convex half mold 7 can be moved along the forming direction D by means of an actuator (e.g., a hydraulic, mechanical, or electrical actuator, not shown).

[0071] In the example shown, the concave mold half 6 is positioned below the convex mold half 7. However, this condition is not required, and in embodiments not shown, the concave mold half 6 may be positioned above the convex mold half 7, or the concave mold half 6 and the convex mold half 7 may be aligned along a horizontal or inclined molding direction. The concave mold half 6 has a molding cavity 8 for molding the outer surface of the object 3.

[0072] The molding cavity 8 has a bottom surface 10 or transverse surface arranged laterally (specifically perpendicularly) relative to the molding direction D. The bottom surface 10 is intended to form the transverse wall 5 of the object 3 from the outside.

[0073] The molding cavity 8 also has a side surface 11, which is designed to form the side wall 4 of the object 3 from the outside.

[0074] The molding unit 1 has a molding axis Z, which extends parallel to the molding direction D.

[0075] The side surface 11 extends around the forming axis Z.

[0076] The molding unit 1 includes a movable central portion 9, which can be displaced along the molding direction D.

[0077] exist Figures 1 to 5 In the illustrated embodiment, the movable center portion 9 is included in the concave half mold 6. However, this condition is not required, and as will be described in more detail below, the movable center portion 9 may alternatively be included in the convex half mold.

[0078] The movable center part 9 can move forward to the PA position (e.g.) Figure 1 and Figure 2 (as shown) and the retraction position PR (as shown) Figures 3 to 5 The displacement D between the two points is parallel to the forming direction (as shown in the figure).

[0079] The concave half mold 6 includes a base 13 in which a movable central portion 9 is received. More specifically, the movable central portion 9 is received in a hole 14 formed in the base 13, such that the movable central portion 9 and the base 13 are allowed to move relative to each other along the forming direction D.

[0080] In the forward position PA, the movable center portion 9 extends from the base 13 toward the opposite half-mold (that is, toward the convex half-mold 7). In the forward position PA, the movable center portion 9 is designed to receive the metered blank 2. More specifically, the movable center portion 9 is defined transversely to the forming direction D by a contact surface 12 adapted to receive the metered blank 2. The metered blank 2 can be conveyed toward the forming unit 1 by a conveying element (not shown) and released onto the movable center portion 9 when it is in the forward position PA. The metered blank 2 can be specifically arranged to rest on the contact surface 12, which can be the upper surface of the movable center portion 9.

[0081] The contact surface 12 can be a flat surface, so that the quantitative blank 2 can be stably positioned on the contact surface 12.

[0082] At the retracted position PR, the forming of object 3 is complete. However, the movable center part 9 can even move to the retracted position PR before object 3 is fully formed, as will be described in more detail below.

[0083] The movable center portion 9 is slidable between a forward position PA and a retracted position PR due to a drive element (not shown). In one embodiment, the movable center portion 9 may be slidable between the forward position PA and the retracted position PR due to a spring system. The movable center portion 9 may have a widened portion 16 at its end opposite to the contact surface 12. The widened portion 16 may be defined by a stop surface 17 that extends transversely to the forming direction D.

[0084] A shoulder 15 can be provided along the hole 14 of the base 13, and the stop surface 17 of the movable center portion 9 can abut against this shoulder in the forward position PA. This ensures that the positioning of the base 13 and the movable center portion 9 relative to each other is constant in the forward position PA.

[0085] A molding surface 18, specifically having an annular shape, is defined on the base 13. The molding surface 18 partially defines the bottom surface 10 of the molding cavity 8. The bottom surface 10 of the molding cavity 8 is also defined by a contact surface 12 of the movable center portion 9. In the retracted position PR, the contact surface 12 can be flush with the molding surface 18, such that the movable center portion 9 and the molding surface 18 together mold from the transverse wall 5 of the external molding object 3.

[0086] In the forward position PA, the movable central part 9 extends from the base 13.

[0087] The concave half mold 6 also includes a plurality of parting blocks 19, which can move laterally (specifically perpendicular to) the molding direction D to define a variable volume molding area 20.

[0088] The parting block 19 is defined by a corresponding forming surface 21, which is adapted to contact the moldable material of the forming preform 2 to at least partially form the sidewall 4 of the object 3 from the outside.

[0089] The number of fractal blocks 19 can be chosen arbitrarily. For example, there can be four fractal blocks 19, or there can be more than four fractal blocks 19.

[0090] Partition block 19 can, for example, Figure 1 and Figure 2 The extended configuration C1 shown is as follows Figure 5The molding configurations C2 shown can be moved between each other. In molding configuration C2, the shape of the variable volume molding region 20 defined between the parting block 19 and the bottom surface 10 is substantially the same as the shape of the outer surface of the object 3. In contrast, in expansion configuration C1, the size of the variable volume molding region 20 is larger than the outer dimensions of the object 3.

[0091] In the example shown, the parting block 19 is also configured to receive the preform 2 statically before it is formed between the convex half-mold 7 and the concave half-mold 6. The parting block 19 is defined by a receiving surface 29, which in the example is the upper surface of the parting block 19, arranged to support the preform 2 released onto the concave half-mold 6. The receiving surface 29 faces the convex half-mold 7. The receiving surface 29 may be substantially flat.

[0092] The convex die 7 includes a punch 22 for forming an object 3 from within. The punch 22 is defined by an end forming surface 23 of a transverse wall 5 for forming the object 3 from within. The punch 22 is also defined by a lateral forming surface 24 of a side wall 4 for forming the object 3 from within. The lateral forming surface 24 extends about a forming axis Z, while the end forming surface 23 is positioned transversely to the forming axis Z.

[0093] In one embodiment, the punch 22 may be made of multiple parts.

[0094] The convex die 7 also includes a compensating element 25, which is positioned such that it floats relative to the punch 22 along the forming direction D. The compensating element 25 is positioned outside the punch 22. Depending on the structure of the object 3 to be formed, one or more intermediate parts may exist between the punch 22 and the compensating element 25.

[0095] The compensating element 25 may have a tubular shape to house the punch 22 within it.

[0096] The compensating element 25 may have a tubular body 26 with a forming end 27. The forming end may also have a tubular shape and a thickness less than that of the tubular body 26. In this way, the forming end 27 can be inserted between the punch 22 and the parting block 19 to form the edge region 28 of the object 3, such as... Figure 5 As shown.

[0097] The compensating element 25 can be positioned at a height relative to the punch 22, which is variable depending on the mass of the preform 2. In practice, the mass of the preform 2 may vary within a finite range due to many factors, such as tolerances of the components constituting the device into which the forming unit 1 is inserted, the not always constant properties of the moldable material forming the preform 3, any wear, or other phenomena. By positioning the compensating element 25 at a variable height relative to the punch 22 according to the mass of the preform 2, an object 3 with a height H can be obtained, such that... Figure 5 As shown in the magnified details, the height varies depending on the mass of the preform 2. The height H of an object 3 formed from a preform 2 with a relatively large mass is greater than the height of another object 3 formed from a preform 2 with a relatively small mass. If the mass of the preform 2 varies within a predetermined tolerance, the variation in height H in the object 3 is not a problem.

[0098] During operation, molding unit 1 is initially positioned in an open configuration Q1 (e.g., Figure 1 As shown in the diagram, in this configuration, the concave half-mold 6 and the convex half-mold 7 are spaced apart.

[0099] The movable center portion 9 is arranged in the forward position PA, in which it extends relative to the base 13. The movable center portion 9 can be positioned such that, in the forward position PA, the contact surface 12 of the movable center portion 9 is at the same height as the receiving surface 29 of the parting block 19 along the forming direction D. In this way, the receiving surface 29 and the contact surface 12 define a support plane on which the metering blank 2 can be released.

[0100] Parting block 19 is positioned in expansion configuration C1, in which the dimension of variable volume forming region 20 perpendicular to forming direction D is greater than the dimension of object 3 perpendicular to forming direction D.

[0101] In the convex die 7, the compensating element 25 is arranged in a retracted position relative to the end forming surface 23 of the punch 22, in which the forming end 27 of the compensating element 25 is positioned at a relatively large distance from the end forming surface 23 of the punch 22.

[0102] A preform 2 of a moldable material (e.g., cellulose) is positioned in the molding unit 1 by a conveying element (not shown), specifically in a concave half mold 6.

[0103] If the preform 2 is made of a natural fiber-based material (e.g., cellulose), the preform 2 can be cut from a sheet or roll of the natural fiber-based material, or formed into a discrete preform by precompacting the natural fibers. The preform 2 includes a central portion 30 and a peripheral portion 31. The peripheral portion 31 is defined by a peripheral edge 40.

[0104] The central portion 30 of the quantitative blank 2 is arranged to be supported on the contact surface 12 of the movable central portion 9, while the peripheral portion 31 of the quantitative blank 2 is arranged to be supported on the receiving surface 29 of the parting block 19.

[0105] In this way, when the preform 2 is inserted into the molding unit 1, the preform 2 is supported at its central portion 30 and its peripheral portion 31. This prevents the preform 2 from undergoing undesirable deformation and helps the preform 2 maintain a flat and extended shape that is optimal for subsequent molding steps.

[0106] Then, at least one die half selected from the concave die half 6 and the convex die half 7 moves toward the other die half selected from the convex die half 7 and the concave die half 6, so that the metering blank 2 contacts the punch 22. In the example shown, this is achieved by moving the concave die half 6 upward, while the convex die half 7 remains in a fixed position along the forming direction D. This achieves the locking configuration Q2, as... Figure 2 As shown, in this locking configuration, the preform 2 is locked between the concave die half 6 and the convex die half 7. More precisely, in locking configuration Q2, the preform 2 is locked between the movable center portion 9 and the punch 22.

[0107] The lock configuration Q2 is achieved at the end of the locking step.

[0108] In order to achieve the locking configuration Q2, a relative movement parallel to the forming direction D occurs between the two parts of the center portion 30 of the locking quantitative blank 2 (i.e., the movable center portion 9 and the half mold facing the movable center portion 9).

[0109] Clamping the preform 2 between the movable center portion 9 and the half-mold (i.e., the convex half-mold 7) facing the movable center portion prevents lateral displacement of the preform 2, that is, prevents the preform 2 from shifting laterally in the forming direction D. This prevents the preform 2 from being eccentrically positioned in the forming cavity 8. In this way, the quality of the formed object 3 is improved.

[0110] Continue moving the concave die 6 toward the convex die 7, compressing the center portion 30 of the quantitative blank 2 between the punch 22 and the movable center portion 9, as... Figure 3 As shown. In this way, the thickness of the moldable material is reduced and its density is increased, thereby forming the transverse wall 5 of object 3.

[0111] As the concave die 6 moves toward the convex die 7 to compress the metering blank 2, the base 13 moves forward toward the punch 22 more than the movable center portion 9. The effect of this relative movement is that the movable center portion 9 gradually extends less into the molding cavity 8. In other words, the movable center portion 9 gradually extends less between the parting blocks 19 until it reaches the retracted position PR, as... Figure 3 As shown, in this retracted position, the contact surface 12 is flush with the molding surface 18 of the base 13, that is, the contact surface 12 and the molding surface 18 are at the same height along the molding direction D.

[0112] Due to the interaction between the punch 22 and the concave die 6, the metering blank 2 deforms in a concave shape and is gradually pushed into the forming cavity 8. Figure 3 In the configuration shown, the preform 2 is no longer placed on the receiving surface 29 of the parting block 9. The parting blocks begin to move toward each other, gradually reducing the size of the variable volume forming region 20 so as to act on the peripheral portion 31 of the preform 2 to form the sidewall 4 of the object 3. Figure 4 The compaction configuration Q3 is shown, in which the base 13 and the movable center portion 9 have reached their final positions relative to the punch 22. The transverse wall 5 of the object 3 is formed by the center portion 30 of the metering blank 2 in such a way that the center portion is pressed until a defined degree of compaction is achieved. The parting block 19 also reaches its forming configuration C2, i.e., its final configuration relative to the punch 22. The sidewall 4 is formed substantially in such a way that, except for its upper edge region, it has not yet interacted with the die components.

[0113] At this point, the compensating element 25 (which has begun to move toward the end face 23 of the punch 22) is inserted between the parting block 19 and the punch 22 to compact the moldable material of the edge region 28 of the molded object 4. Figure 5 This situation is illustrated in the diagram, where molding unit 1 is in the final molding configuration Q4. The compensating element 25 is pushed towards the movable center portion 9 until the desired compaction degree of the object 3 is achieved. Depending on the actual mass of the preform 2 (which may vary within a predetermined range), the final position of the compensating element 25 relative to the movable center portion 9 may vary. Therefore, the height H of the sidewall 4 of the object is affected by the mass of the preform 2. A larger mass preform 2 results in a greater height H compared to a smaller mass preform 2. Limited variations in height H do not impair product functionality and are therefore acceptable.

[0114] Object 3 has now reached its defined shape and can be removed from molding unit 1, which can then return to... Figure 1 The open configuration Q1 shown is for receiving a new quantitative billet 2 to be formed.

[0115] The sequence of forming the transverse wall 5 and the side wall 4 by compacting the corresponding portions of the quantitative billet 2 may be similar to... Figures 1 to 5 The differences are shown. The transverse wall 5 can be formed first by compacting the moldable material between the punch 22, the movable center portion 9, and the base 13, and then the side wall 4 can be formed by compacting the moldable material between the punch 22 and the parting block 19. Alternatively, the side wall 4 can be formed first, followed by the transverse wall 5, or the moldable material in both the side wall 4 and the transverse wall 5 can be compacted simultaneously.

[0116] exist Figures 1 to 5 In the example shown, before the forming step begins, the preform 2 is locked between the movable center portion 9 and the punch 22, i.e., when the preform 2 still has a flat shape and has not yet significantly deformed between the convex half-die 7 and the concave half-die 6. Alternatively, the preform 2 can be locked between the movable center portion 9 and the half-die facing the movable center portion when forming of the preform 2 has already begun (e.g., when the preform 2 has already adopted a concave shape due to the interaction between the concave half-die 6 and the convex half-die 7).

[0117] Note that during the locking step, the central portion 30 of the preform 2 is locked between the movable central portion 9 and the half-mold facing the movable central portion 9, in this case, the convex half-mold 7. On the other hand, the peripheral portion 31 (specifically the peripheral edge 42) remains free to move during the locking step. This prevents the preform 2 from breaking or tearing when the moldable material deforms between the movable central portion 9 and the parting block 19 to form the sidewall 4 of the object 3. The peripheral portion 31 can indeed freely follow the movement of the central portion 30 without being constrained at its peripheral edge 40.

[0118] Furthermore, it is noted that during the locking step, the moldable material forming the central portion 30 is clamped between the movable central portion 9 and the half-mold facing the movable central portion 9, but the final compaction is not achieved. (Comparison) Figure 2 and Figure 5 This is obvious. What is truly clear is the thickness (e.g., the thickness of the central portion 30 of the quantitative blank 2 at the end of the locking step) Figure 2 (As shown) is greater than the thickness of the transverse wall 5 in object 3 (e.g.) Figure 5 (As shown).

[0119] After the central portion 30 is locked between the movable central portion 9 and the half-mold facing the movable central portion 9, the peripheral portion 31 adjacent to the central portion 30 begins to deform to begin forming the sidewall 4. This is due to the relative movement that occurs between the movable central portion 9 and the half-mold facing the movable central portion 9. Therefore, the central portion 30 of the metered blank 2 continues to be compressed while the peripheral portion 31 deforms until the final compaction is achieved.

[0120] Therefore, the fibers in the central layer of the central portion 20 still have a certain degree of mobility even at the end of the locking step, which allows these fibers to better adapt to the deformation of the moldable material when the sidewall 4 is formed.

[0121] Figures 6 to 10 A molding unit 101 according to an alternative embodiment is shown. The main difference between molding unit 101 and molding unit 1 is that it includes a movable central portion 109, which is incorporated within a convex half-mold 107, rather than as... Figures 1 to 5 As shown in the embodiment, it is included in a concave half-mold.

[0122] Previous reference Figures 1 to 5 The description of molding unit 1 shown should be understood to also apply to molding unit 101, unless otherwise stated.

[0123] The convex die 107 of the forming unit 101 includes a punch 122 made of at least two parts, namely, a forming sleeve 32 that accommodates a movable central portion 109. The forming sleeve 32 has a side surface 24 (which is similar to the reference surface). Figures 1 to 5 The molding sleeve 32 is defined by a front molding surface 33 transverse to the molding axis Z, which is arranged as part of the transverse wall 5 of the object 3 from the inside.

[0124] The movable center portion 109 is defined by a contact surface 12 adapted to contact the metering blank 2 to lock the metering blank against a mold half facing the movable center portion 109, i.e., against a concave mold half 106. The contact surface 12 is arranged transversely (specifically perpendicularly to) the forming axis Z. The contact surface 12 may be a flat surface.

[0125] The movable center section 109 can move to the forward position PA (e.g.) Figure 6 and Figure 7 (as shown) and the retraction position PR (as shown) Figures 8 to 10The movable center portion 109 is displaced parallel to the forming direction D between the forming sleeve 32 and the concave mold half 107 (as shown). In the forward position PA, the movable center portion 109 extends from the forming sleeve 32 toward the concave mold half 107. In the retracted position PR, the movable center portion 109 is fully received inside the forming sleeve 32. In the retracted position PR, the contact surface 12 of the movable center portion 109 is flush with the front forming surface 33 of the forming sleeve 32. In the retracted position PR, the contact surface 12 and the front forming surface 33 together define an end forming surface 123, which may optionally be flat, for forming the transverse wall 5 of the object 3 from the inside.

[0126] exist Figures 6 to 10 In the illustrated embodiment, the movable center portion 109 may also have a widened portion 116 at its end opposite the contact surface 12. The widened portion 116 is defined by a stop surface 117 that extends transversely to the molding direction D. A shoulder 115 may be present inside the molding sleeve 32, against which the stop surface 117 of the movable center portion 109 can abut in the forward position PA. This ensures that the positioning of the molding sleeve 32 and the movable center portion 109 relative to each other is constant in the forward position PA. The convex half-mold 107 also includes a compensating element 25, which is not described in detail as it is similar to the reference. Figures 1 to 5 The compensation element 25 is described.

[0127] The concave mold 106 includes a base 113 defined by a molding surface 118 for molding the transverse wall 5 of the external object 3. The molding surface 118 faces the convex mold 107, and in the example shown, the molding surface is substantially flat and arranged transversely to (specifically perpendicular to) the molding axis Z.

[0128] The concave half mold 106 also includes a plurality of parting blocks 19, which can be expanded in configuration C1 (such as... Figures 6 to 8 (as shown) and molding configuration C2 (as shown) Figure 9 and Figure 10 Move between (as shown). Partial block 19 will not be described in detail again, as previously referenced... Figures 1 to 5 The description of the fractal block 19 shown also applies to Figures 6 to 10 The shown is the parting block 19.

[0129] During operation, such as Figure 6 As shown, the concave half-mold 106 and the convex half-mold 107 are initially spaced apart from each other and arranged in an open configuration Q1. The parting block 19 is in an expanded configuration C1, while the movable central portion 109 extends from the forming sleeve 32 and is in an advancing position PA. A metering blank 2 (e.g., made of a natural fiber-based material) is positioned on the receiving surface 29 of the parting block 19 by a conveying element not shown.

[0130] At least one die half selected from concave die half 106 and convex die half 107 moves toward the other die half selected from convex die half 107 and concave die half 106. In the example shown, concave die half 106 moves toward convex die half 107 along the forming direction D. When concave die half 106 moves in this manner, the central portion 30 of the metering blank 2 contacts the movable central portion 109 extending from the forming sleeve 32. The movable central portion 109 deforms the metering blank 2 toward the bottom surface 10, the metering blank being arranged concavely and pushed into the forming cavity 8. At a certain moment, reaching Figure 7 The locking configuration Q2 shown in the diagram locks the preform 2 between the movable center portion 109 and the half-mold (i.e., the concave half-mold 106) facing the movable center portion. More specifically, the center portion 30 of the preform 2 contacts the contact surface 12 of the movable center portion 109 and the forming surface 118 of the base 113.

[0131] In the locking configuration Q2, the movable center portion 109 and the half-mold facing the movable center portion clamp the metering blank 2 to prevent the metering blank 2 from shifting in a direction transverse to the forming direction D, which allows the metering blank 2 to remain correctly centered in the forming unit 101 even during forming.

[0132] It should be noted that, although in Figures 1 to 5 In the embodiment shown, the locking configuration Q2 is achieved while the quantitative billet 2 still has a flat structure, but... Figures 6 to 10 In the illustrated embodiment, the locking configuration Q2 is achieved during the forming step of the preform, i.e., after the preform 2 has been deformed to give it a concave shape. Figure 7 In the locking configuration Q2 shown, the split block 19 is still arranged in the expanded configuration C1, while the movable center portion 109 is still arranged in the forward position PA.

[0133] Then, the concave half-mold 106 moves further toward the convex half-mold 107, while the movable central portion 109 moves rearward into the forming sleeve 32 until it reaches the retracted position PR, where the contact surface 12 of the movable central portion is aligned with the front forming surface 33 of the forming sleeve 32, and they together define the end forming surface 123. In this way, the moldable material forming the central portion 30 of the preform 2 is compacted between the movable central portion 109 and the base 113, thereby forming the transverse wall 5 of the object 3. Figure 8 This situation is illustrated in the image.

[0134] Parting block 19 now moves from expansion configuration C1 to molding configuration C2, as follows Figure 9As shown, the moldable material of the peripheral portion 31 of the quantitative blank 2 is compacted in the same way, and the sidewall 4 of the object 3 is formed. It should be noted that the parting block 19 can move from the expansion configuration C1 to the molding configuration C2 after the transverse wall 5 is fully formed or at the same time as the transverse wall 5 is formed.

[0135] Finally, the compensation element 25 is inserted between the punch 122 and the parting block 19 to form the edge region 28 of the object 3, thereby compressing the moldable material forming the sidewall 4 along the forming direction D and positioning itself at a distance H from the base 3, which depends on the mass of the preform 2 being processed.

[0136] Object 3 was formed in this way.

[0137] Also in Figures 6 to 10 In the example shown, the central portion 30 of the quantitative blank 2 is locked between the movable central portion 109 and the half-mold facing the movable central portion 109, which occurs due to the relative movement of the movable central portion 109 and the half-mold facing the movable central portion 109 parallel to the forming direction D.

[0138] Also in Figures 6 to 10 In the example shown, at the end of the locking step (i.e., when the lock is reached) Figure 7 (In the locking configuration Q2 shown), the moldable material in the central portion 30 has not yet reached its final compaction. The moldable material in the central portion 30 continues to be compressed even after the locking step is completed. Specifically, the moldable material in the central portion 30 reaches its final compaction at the end of the molding step, at which point the peripheral portion 31 has also been at least partially deformed.

[0139] Finally, also in Figures 6 to 10 In the example shown, the locking step only affects the central portion 30. At the end of the locking step, the peripheral portion 31 (specifically its peripheral edges) remains free to move. Even though the preceding description referenced a preform 2 containing a natural fiber-based material, as... Figures 1 to 10 The forming unit shown can also be used to process preforms made from synthetic polymer materials.

[0140] Figures 10 to 15 A molding unit 201 according to an alternative embodiment is shown. Molding unit 201 is particularly suitable for processing preforms 2 made of synthetic polymer materials, although the molding unit can theoretically be used in combination with preforms made of natural fiber-based materials. The preform 2 may, for example, have a quadrilateral shape in a plan view, specifically a square or rectangle, but may also be circular, elliptical, or other shapes. The preform 2 may be flat or concave.

[0141] Molding unit 201 includes a concave half mold 206, which is connected to... Figures 1 to 5 Similar to the molding unit 1 shown, it has a movable center portion 209, which can move along the molding direction D to the forward position PA (e.g., Figures 11 to 13 (as shown) and the retraction position PR (as shown) Figure 15 It can move between (as shown). The movable central part 209 is similar to the reference. Figures 1 to 5 The movable center section 9 is described, and will not be described in detail again.

[0142] and Figures 1 to 5 Similarly, the movable central portion 209 is housed inside the base 213 and can slide within the hole 214 of the base 213.

[0143] exist Figures 1 to 5 In this case, since both the movable center portion 9 and the hole 14 have a cylindrical shape, the movable center portion 9 is joined to the hole 14 in a shape-connected manner.

[0144] exist Figures 10 to 15 In this case, the hole 214 not only functions to accommodate the movable center portion 209, but also facilitates the molding of the object 3. More specifically, the hole 214 is defined by a molding side surface 38, which is used to mold the sidewall 4 of the object 3 from the outside. Since the object 3 to be molded is a capsule defined by sidewalls 204 having a truncated conical shape, the molding side surface 38 defining the upper portion of the hole 214 is truncated conical, while the movable center portion 209 is cylindrical. Therefore, a free space 34 is defined between the movable center portion 209 and the base 213. However, at the lower end of the hole, the hole 214 has a guide portion 35, which may be cylindrical, for engaging with the shape of the movable center portion 209 and guiding the movable center portion 209 during movement along the molding direction D.

[0145] The concave mold 206 also includes a parting block 19, which is structurally similar to the previously described parting block 19; however, as will be described in more detail below, when the preform 2 is inserted into the molding unit 201, Figures 10 to 15 The parting block 19 shown does not support the quantitative blank 2, but only has a accommodating function.

[0146] The forming unit 201 also includes a convex die half 207, which includes a punch 222 disposed inside the locking sleeve 36. The punch 222 is defined by an end forming surface 23 and a lateral forming surface 24, as previously referenced. Figures 1 to 5 As described. Punch 222 is configured to form the inner surface of object 3.

[0147] The locking sleeve 36 has a locking surface 37 facing the concave mold half 206. The locking surface 37 is configured to lock the metered blank 2 in contact with the base 213 when the moldable material is pressed to form the object 3. The locking surface 37 is arranged transversely to (specifically perpendicular to) the forming direction D and may be a flat annular surface.

[0148] Punch 222 and locking sleeve 306 are movable relative to each other; that is, one component selected from punch 222 and locking sleeve 306 moves in a linear translational manner relative to another component selected from locking sleeve 36 and punch 222 along the forming direction D. In the example shown, locking sleeve 36 moves relative to punch 222 due to the thrust applied by concave die 206.

[0149] Punch 222 can be positioned at the reverse position PB, such as Figures 11 to 13 As shown, in the retracted position PB, the forming end of the punch 222, defined by the end forming surface 23 and the lateral forming surface 24, is arranged inside the locking sleeve 36. The punch 222 can also be positioned in the extended position PS, as shown... Figure 15 As shown, in this extended position, the forming end of the punch 222 extends from the locking sleeve 36 to penetrate the forming cavity 8.

[0150] Convex half mold 207 (excluding reference) Figures 1 to 10 The compensation element 25 is described.

[0151] During operation, molding unit 201 is initially in an open configuration Q1 (e.g., Figure 11 As shown), in this open configuration, the concave half-mold 206 and the convex half-mold 207 are spaced apart. The movable center portion 209 is arranged in the forward position PA, in which the contact surface 12 is flush with the molding surface 218 of the base 213. The molding surface defines the base 213 around the hole 214 on the upper portion of the base.

[0152] When the movable center portion 209 is in the forward position PA, a slit is defined between the contact surface 12 of the movable center portion 209 and the molded surface 218 of the base 213 due to the shape difference between the movable center portion 209 and the hole 213.

[0153] Fractal block 19 is in the expanded configuration C1.

[0154] A metered preform 2 of moldable material (not shown) is released between a concave die half 206 and a convex die half 207 by a conveying element. If the metered preform 2 is made of a synthetic polymer material, it can be conveyed by the conveying element toward the forming unit 201 after separation from the continuous extrudate from the extruder. In contrast, if the metered preform 2 is made of a natural fiber-based material, it can be cut from a roll of starting material or obtained by compacting powder material.

[0155] The preform 2 is positioned on the concave half mold 206, such that the central portion 30 of the preform is arranged on the movable central portion 209, and the peripheral portion 31 of the preform is supported on the base 213, specifically on the forming surface 218 of the base 213 surrounding the hole 214. At this time, the preform 2 is spaced apart from the parting block 19.

[0156] Then, as Figure 12 As shown, the parting block 19 moves toward the forming axis Z and enters the forming configuration C2. The parting block 19 has not yet come into contact with the metering blank 2, and at this stage the parting block acts as a receiving element that laterally receives the metering blank 2 to prevent the metering blank from being positioned too eccentrically relative to the forming axis Z.

[0157] Now, the half-mold selected from concave half-mold 206 and convex half-mold 207 moves toward the other half-mold selected from convex half-mold 207 and concave half-mold 206. In the example shown, concave half-mold 206 moves toward convex half-mold 207, for example, by moving concave half-mold 206 vertically upward. The effect of this relative movement is that locking sleeve 36 penetrates between parting blocks 209, the forming surface 21 of which acts as a guide for locking sleeve 36.

[0158] In this way, the metered blank 2 comes into contact with the locking sleeve 36, specifically with the locking surface 37 of the locking sleeve. In this way, the metered blank 2 is locked between the base 213 and the locking sleeve 36. This occurs as follows: Figure 13 In the locking configuration Q2 of the type shown, the peripheral portion 31 of the quantitative blank 2 is locked between the locking surface 37 of the locking sleeve 36 and the forming surface 218 of the base 213.

[0159] Locking the preform 2 between the locking sleeve 36 and the concave half mold 206 prevents lateral displacement of the preform 2, which ensures good alignment of the preform 2 in the molding unit 201.

[0160] As the concave die 206 continues to move toward the convex die 207, the locking sleeve 36 is pushed upward by the concave die 206. Therefore, in the example shown, the punch 222, positioned at a fixed location along the forming axis Z, begins to extend from the locking sleeve 36. Simultaneously, the movable center portion 209 moves rearward toward the retracted position PR, and the metering blank 2 takes on a concave shape, as... Figure 14 As shown, the moldable material has not yet reached its final shape, thickness, or compaction.

[0161] Figure 15 The final molding configuration Q4 is shown, in which the movable center portion 209 has reached the retracted position PR, the parting block 19 is in the molding configuration C2, and the punch 222 is arranged in the extended position PS. In this configuration, an object 3 is formed between the concave half-die 206 and the convex half-die 207. As previously described, this object has a capsule shape, which is used to contain powder material from which extractable substances, such as coffee, can be extracted. The capsule includes a transverse wall 5 formed between the movable center portion 209 and the end molding surface 23 of the punch 222. The capsule also includes a sidewall 4 having a truncated conical shape formed between the lateral molding surface 24 of the punch 222 and the molding side surface 38 of the hole 214. The capsule also has a flange 39 formed between the molding surface 218 of the base 213, the locking surface 37 of the locking sleeve 36, and the molding surface 21 of the parting block 19.

[0162] After the capsule has been held in the molding unit 201, which is arranged in the final molding configuration Q4, for a period of time sufficient to fix its shape, the capsule is removed from the molding unit 201 and a new molding cycle can begin.

[0163] exist Figures 11 to 15 In the embodiment shown, the peripheral portion 31 of the quantitative blank 2 is locked between the locking sleeve 36 and the half-mold facing the locking sleeve 36 due to the relative movement between the locking sleeve 36 and the half-mold facing the locking sleeve 36 along a direction parallel to the forming direction D.

[0164] Furthermore, when the locking configuration Q2 is reached, i.e., at the end of the locking step, the peripheral portion 31 of the metered blank 2 has not yet been compressed to its final compaction. Even after another portion of the metered blank 2 adjacent to the peripheral portion 31 begins to form the sidewall 204 of the object 3, the peripheral portion 31 continues to be compressed. (Comparison) Figure 13 and Figure 15 This can be clearly seen in the figure, which shows that even after the locked configuration Q2 is reached, the thickness of the peripheral portion 31 of the billet continues to decrease.

[0165] In short, Figures 1 to 15The illustrated molding unit implementations share a common feature: a preform of molding material is locked between a movable portion and a mold half facing the movable portion before the preform is fully molded. This occurs by bringing the movable portion and the mold half facing the movable portion into contact with the preform on opposite sides, thus clamping the preform between the movable portion and the mold half facing the movable portion. In this way, undesirable displacement of the preform during the molding process is avoided.

[0166] In embodiments not shown, Figures 1 to 15 The parting block 19 of any of the molding units shown may not exist.

[0167] In the example shown, a single movable portion 9, 109, 209 is illustrated. In embodiments not shown, multiple movable portions may exist, for example, one coaxially positioned inside another, and may be retractably movable relative to each other.

[0168] The movement of movable parts 9, 109, and 209 can be passive, that is, achieved by an elastic element such as a spring. Alternatively, a drive element for actively moving movable parts 9, 109, and 209 can be provided, such as a hydraulic, pneumatic, or other type of drive element.

[0169] In addition to the functions described above, the movable parts 9, 109, and 209 may have other additional functions. For example, the movable parts 9, 109, and 209 may assist in removing the formed object from the mold, calibrating the compressive force applied to the metered blank, or other functions.

Claims

1. A method comprising the following steps: - Insert a preform (2) made of moldable material between the concave half mold (6; 106; 206) and the convex half mold (7; 107; 207); - The object (3) is formed by moving at least one half of the concave half (6; 106; 206) and the convex half (7; 107; 207) along the forming direction (D) toward the other half of the convex half (7; 107; 207) and the concave half (6; 106; 206) to press the quantitative blank (2) between the convex half (7; 107; 207) and the concave half (6; 106; 206); A locking step is provided before the end of the molding step to lock a portion of the preform (2) between the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207), wherein the half-mold selected from the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207) includes a movable central portion (9; 109; 209) displaceable between a forward position (PA) and a retracted position (PR), the movable central portion (9; 109; 209) being in the forward position (PA) during the locking step of the portion of the preform (2), and the movable central portion (9; 109; 209) being in the retracted position (PR) at least at the end of the molding step. Furthermore, during the locking step, the portion of the quantitative blank (2) is held between the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207), but has not yet reached the final compaction degree. After the other portion of the quantitative blank (2) adjacent to the portion of the quantitative blank (2) is deformed, the portion of the quantitative blank (2) is compressed between the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207) until the final compaction degree is reached.

2. The method according to claim 1, wherein, The object (3) is a concave object having a sidewall (4) and the sidewall is closed at one end by a transverse wall (5), and the other part of the preform (2) is deformed during the forming step to form the sidewall (4).

3. The method according to claim 1 or 2, wherein, After the locking step and during the molding step, the moldable material in the portion of the preform (2) is thinned to achieve the final compaction.

4. The method according to any one of the preceding claims, wherein, The portion of the quantitative blank (2) is the peripheral portion (31), and wherein, in the locking step, the peripheral portion (31) is locked between the concave half-die (6; 106; 206) and the convex half-die (7; 107; 207), while the central portion (30) of the quantitative blank (2) is supported on the movable central portion (9; 109; 209) arranged in the forward position (PA).

5. The method according to claim 4, wherein, The peripheral portion (31) of the quantitative blank (2) is locked between the locking sleeve (36) of the convex half mold (7; 107; 207) and the forming surface (218) of the concave half mold (6; 106; 206), the forming surface (218) being arranged outside and around the movable central portion (9; 109; 209).

6. The method according to any one of claims 1 to 3, wherein, The portion of the quantitative blank (2) is a central portion (30), which is locked in the locking step between the movable central portion (9; 109; 209) arranged in the forward position (PA) and a half mold facing the movable central portion (9; 109; 209), the half mold being selected from the convex half mold (7; 107; 207) and the concave half mold (6; 106; 206).

7. The method according to claim 6, wherein, The other part of the quantitative blank (2) is the peripheral part (31) arranged outside the central part (30), and wherein, during the locking step, the peripheral part (31) of the quantitative blank (2) is in a free state.

8. A method comprising the following steps: - Insert a preform (2) made of moldable material between the concave half mold (6; 106; 206) and the convex half mold (7; 107; 207); - By moving at least one half of the concave half (6; 106; 206) and the convex half (7; 107; 207) along the forming direction (D) toward the other half of the convex half (7; 107; 207) and the concave half (6; 106; 206), the quantitative blank (2) is pressed between the convex half (7; 107; 207) and the concave half (6; 106; 206), thereby forming the object (3); A locking step is provided before the end of the molding step to lock a portion of the preform (2) between the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207), wherein the half-mold selected from the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207) includes a movable central portion (9; 109; 209) displaceable between a forward position (PA) and a retracted position (PR), the movable central portion (9; 109; 209) being in the forward position (PA) during the locking step of the portion of the preform (2), and the movable central portion (9; 109; 209) being in the retracted position (PR) at least at the end of the molding step. The quantity blank (2) has a central portion (30) and a peripheral portion (31), and in the locking step, the peripheral portion (31) of the quantity blank (2) is in a free state, while the central portion (30) of the quantity blank (2) is locked between the movable central portion (9; 109; 209) arranged in the forward position (PA) and a half mold facing the movable central portion (9; 109; 209), the half mold being selected from the convex half mold (7; 107; 207) and the concave half mold (6; 106; 206).

9. The method according to claim 8, wherein, After the locking step and during the molding step, the moldable material in the portion of the preform (2) is thinned.

10. The method according to any one of claims 6 to 9, wherein, The central portion (30) of the quantitative blank (2) is locked between the movable central portion (9; 109; 209) included in the concave half-die (6; 106; 206) and the punch (22) included in the convex half-die (7; 107; 207).

11. The method according to any one of claims 6 to 9, wherein, The central portion (30) of the preform (2) is locked between the movable central portion (9; 109; 209) and the transverse surface (10), the movable central portion being included in the convex half mold (7; 107; 207), the transverse surface being transverse to the forming direction (D) defining the forming cavity (8) of the concave half mold (6; 106; 206).

12. The method according to any one of the preceding claims, wherein, During the step of inserting the preform (2) between the concave half-die (6; 106; 206) and the convex half-die (7; 107; 207), the movable central portion (9; 109; 209) in the forward position (PA) receives the preform (2) and supports the preform on the movable central portion (9; 109; 209).

13. The method according to any one of the preceding claims, wherein, The preform (2) is made from a non-extrudable material containing fibers.

14. The method according to any one of the preceding claims, wherein, The half-mold selected from the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207) includes a plurality of parting blocks (19) movable transversely to the forming direction (D) between an expansion configuration (C1) and a forming configuration (C2), wherein the parting blocks (19) are arranged in the expansion configuration (C1) when the preform (2) is received between the concave half-mold (6; 106; 206) and the convex half-mold (7; 107; 207), and wherein the parting blocks (19) in the forming configuration (C2) form at least one lateral portion of the object (3).

15. The method according to claim 14, wherein, The parting block (19) is defined by a receiving surface (29) that receives the quantitative blank (2) supported on the receiving surface (29) in the expansion configuration (C1).

16. The method according to claim 14 or 15, wherein, The concave half mold (6; 106; 206) includes a base (13) having a hole (14), the movable central portion (9; 109; 209) being received in the hole, and wherein, in the forward position (PA), the movable central portion (9; 109; 209) extends from the hole (14) and is inserted between the parting blocks (19).

17. The method according to claim 15 or according to claim 16 when claim 15 is referenced, wherein, At the forward position (PA), the contact surface (12) of the movable center portion (9; 109; 209) which is transverse to the forming direction (D) is flush with the receiving surface (29) of the parting block (19).

18. The method according to any one of claims 1 to 15, wherein, The concave half-mold (6; 106; 206) includes a base (213) having a hole (214), the movable central portion (9; 109; 209) being received in the hole, and wherein, in the forward position (PA), the contact surface (12) of the movable central portion (9; 109; 209) defining the forming direction (D) is flush with the surface (218) of the base (213) surrounding the hole (14).

19. The method according to any one of the preceding claims, wherein, The concave half-mold (6; 106; 206) has a forming cavity (8) defined by a transverse surface (10) transverse to the forming direction (D), and wherein, during the forming step, a compensating element (25) included in the convex half-mold (7; 107; 207) is positioned at a distance from the transverse surface (10) such that the object (3) has a dimension (H) measured along the forming direction (D), the distance depending on the mass of the preform (2), the greater the mass of the preform (2), the larger the dimension.

20. The method according to claim 19 when claim 14 is referenced, wherein, The compensation element (25) has a tubular body (26) defined by a molding end (27) which is inserted between the parting block (19) and the convex molding element (22; 122) of the convex half mold (7; 107; 207) during the molding step.

21. The method according to claim 1, wherein, The quantitative blank (2) has a central portion (30) and a peripheral portion (31), wherein the peripheral portion (31) is deformed to form the object (3) after the central portion (30) has been at least partially compressed to form the transverse wall (5) of the object (3).

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