Apparatus and method for compression molding a converse object

Abstract

Described is an apparatus comprising: dispensing means (2) for dispensing a dose (D) of a polymeric material in a form suitable for compression moulding; a mould (5) for receiving said dose (D) and making a concave object; a plurality of conveying elements (7) of respective doses (D), each of which is configured for picking up a respective dose (D) from the dispensing device (7) and releasing the dose onto the mould (5); a carousel (8) for supporting said conveying elements (7) for feeding each element (7) in the direction of advancement (A) and along a closed path (C) through between the dispensing device (2) and the mould (5) in order to transport the dose (D) to the mould (5); wherein each conveying element (7) comprises a wall (9) for engaging the dose (D), each conveying element being rotatably mounted on the carousel (8) and being rotatable between a pick-up state in which the wall (9) has a respective surface (9a) which contacts the dose (D) transversely to the direction of advancement (A) to intercept and pick up the dose (D) from the dispensing device (2), and a release state in which the dose (D) is released. A release state in which the wall (9) is turned over and the contact surface (9a) faces the mold (5) for releasing the dose (D) into the mold (5) by the action of gravity; and wherein the device comprises a cooling device (11) for each conveying element (7) for cooling said conveying elements (7) at least in a region (T1, T2) of the closed path (C).

Description

Technical Field

[0001] The present invention relates to an apparatus and a method for compression moulding of concave objects, such as any type of container, for example a bottle, a glass, a can or a bowl.

[0002] In particular, the device is used to manufacture concave objects made of a single material or of multiple layers, starting from any polymer material that can be subjected to compression moulding. Background Art

[0003] As is known, an apparatus for manufacturing an object by compression molding a given dose of polymer material comprises an extruder for dispensing the polymer material and a plurality of dies, each of which comprises a male element equipped with a punch and a female element equipped with a cavity. The prior art apparatus also comprises a plurality of conveying elements mounted on a suitable turntable and each of which is configured to convey a dose of polymer material from the extruder to the die.

[0004] After a dose of polymer material is cut off from the extruder, it is picked up and fed to a die generally located above a male element. Subsequently, the male and female elements are moved toward each other to deform the dose, thereby shaping the dose into a desired geometry.

[0005] Devices of this type, such as those described in patent document WO 2020 / 075020 A1 in the name of the same applicant as the present invention, have a series of conveying elements mounted along an annular path defined by a turntable and configured to cut off a dose from an extruder, retain it along the aforementioned annular path and release it over a convex element.

[0006] These elements are configured in the form of a blade defining a flat surface for holding a dose and an upper cutting edge configured for removing the dose from the extruder.

[0007] For this purpose, the blade may also be equipped with a series of air suction holes to maintain the dose in a stable manner during movement along the circular path.

[0008] The blade is movably mounted on the carousel and is movable between two operating configurations: a first raised configuration for picking up a dose and a second lowered configuration for releasing a dose.

[0009] In the first pick-up configuration, the blade is oriented so that the surface is positioned facing the dose at the outlet of the extruder and has a planar extension perpendicular to the direction of advancement along the circular path. Typically, the extruder feeds the dose downwards so that the advancing blade intercepts the dose with a corresponding flat surface. In this case, the cutting edge faces the extruder to remove the dose from the discharge nozzle of the extruder.

[0010] It should be noted that the dose at the discharge port of the extruder is in a semi-solid form, which is achieved by heating the polymer material upstream of the extrusion nozzle.

[0011] For this reason, the dose remains attached to the flat surface of the blade due to the semi-solid state structure (molten material) so as to remain engaged with the blade during the respective delivery step.

[0012] Additionally, the suction action through the holes helps to keep the slurry on the flat surface of the blade.

[0013] After picking up the dose, the blade is lowered to the second release configuration. In this position, the surface is oriented so that the flat extension coincides with the advancement direction of the annular path and faces the male mold element. In addition, in this case, the dose faces downward.

[0014] Thus, the dose is positioned to fall onto the above-mentioned convex element. Furthermore, the release of the dose is facilitated by interrupting the inhalation through the aperture, thereby separating the dose from the corresponding surface by the effect of gravity.

[0015] After releasing a dose into the moulding station, the blade is fed along an annular path in which it returns to the above-mentioned first pick-up state in order to pick up a new dose.

[0016] However, the prior art devices described above have some disadvantages, mainly related to the plasticity of the dose.

[0017] It should be noted that, through thermal inertia, the dose retains heat after being picked up so as to be in a semi-solid state suitable for molding.

[0018] In this case, the chemical properties of the polymer material define stable adhesion to the flat surface, making relative separation difficult and release into the mold difficult.

[0019] In other words, the polymer material leaving the extruder is relatively hot and tends to stick to the surface of the blade, thus adversely affecting the subsequent release step. In fact, in this case, the mere movement of the blade and the interruption of the aspiration action are not sufficient to allow the dose to land in an optimal and accurate manner on the male element of the molding device.

[0020] In addition to the above, it should be noted that the blade upstream of the extruder is still hot due to the dose just released, thus facilitating adhesion to the flat surface of the new dose.

[0021] This situation is determined by the heat exchange effect caused by heat conduction between the dose and the blade. After the dose is released, the blade, which absorbs heat from the dose, immediately returns to the extruder, thus preventing it from returning to ambient temperature. Summary of the invention

[0022] In this context, an object of the present invention is to provide an apparatus and a method capable of overcoming the above-described disadvantages of the prior art.

[0023] More specifically, the object of the invention is to provide an apparatus and a method in which each dose can be correctly positioned in the moulding device.

[0024] Another object is to provide such an apparatus and method which allow correct movement of the dose during the associated steps of picking up the dose from the extruder and delivering and releasing the dose.

[0025] Another object of the invention is to regulate the temperature of the means for holding the dose at least during the step of picking up the dose.

[0026] According to the invention, there is provided an apparatus comprising: a dispensing device for dispensing a dose of polymer material in a form suitable for compression molding; a mold for receiving the dose and manufacturing a concave object; a plurality of conveying elements for corresponding doses, each of which is configured to pick up a corresponding dose from the dispensing device and release the dose onto the mold; a turntable for supporting the conveying elements, the turntable for feeding each conveying element in a forward direction and along a closed path between the dispensing device and the mold to transport the dose to the mold; wherein each conveying element comprises a wall for engaging the dose, each conveying element being rotatably mounted on the turntable and rotatable between a picking state and a releasing state for releasing the dose, in which the wall has a corresponding contact surface transverse to the forward direction for contacting the dose to intercept and pick up the dose from the dispensing device, in which the wall is flipped over and the contact surface faces the mold to release the dose into the mold by the action of gravity; and wherein the apparatus comprises a cooling device for each conveying element for cooling the conveying element at least in a region of the closed path.

[0027] In this way, the pick-up element can dissipate the heat carried by the dose made of molten material, thus preventing any adhesion of the dose on the element.

[0028] Preferably, the cooling device comprises at least one blowing unit for blowing a cooling air flow so as to guide the flow towards the wall of the picking element which is in a corresponding released state; the wall in the released state has a planar extension facing the blowing unit so as to be cooled by the blowing unit upstream of the dispensing device.

[0029] In this case, the blowing unit advantageously has a manifold with an arcuate extension parallel to at least one elongated section of the closed path between the mold and the distribution device in the direction of advancement of the conveying element; said manifold has at least one nozzle for discharging a cooling air flow towards said wall.

[0030] In this way, the wall of each conveying element is cooled upstream of the dispensing device in order to pick up the dose under optimal temperature conditions.

[0031] Advantageously, the cooling device further comprises or alternatively comprises a passage duct formed inside said joining wall for the passage of a cooling fluid for cooling the wall along a circumferential path and in the respective picked-up state and / or released state.

[0032] In this way, the source for supplying cooling fluid is in fluid communication with the inlet stretch of the wall through a supply channel for supplying cooling air formed in the turntable; this channel allows cooling air to flow to the inlet stretch during the entire closed path of the conveying element.

[0033] Advantageously, the element is always cooled to control the temperature of the wall, even when the wall contacts the dose in the molten state. Alternatively, the supply channel may have at least one arcuate portion corresponding to a corresponding angular sector of the closed path; the supply channel allows the passage of cold air towards the inlet extension only when the element is located at an angular sector of said closed path.

[0034] In this way, one or more regions of the closed path in which the pick-up element is thermally conditioned may be selected to recreate the optimal temperature of the walls of the moving dose.

[0035] The present invention also includes a method comprising the steps of: continuously dispensing a certain amount of polymer material in a form suitable for compression molding by a dispensing device; picking up the dose from the dispensing device by a corresponding conveying element mounted on a rotating turntable; feeding the conveying element from the dispensing device to a mold in a forward direction and along a closed path; releasing the dose into the mold to produce a concave object; wherein the method also includes the step of: cooling each conveying element during the step of feeding the conveying element and at least in a region of the closed path.

[0036] Advantageously, the cooling step is achieved by blowing at least one air stream towards the wall of each conveying element configured to engage the dose.

[0037] Additionally or alternatively, the step of cooling the delivery elements is achieved by distributing a cooling fluid to the interior of a wall of each delivery element configured to engage the dose.

[0038] Due to the cooling step, which can be carried out from outside the turntable, the cooling fluid is directed into the channels formed in the wall by blowing a stream of air against the wall of the pickup element and / or inside the wall. In the latter case, the cooling action can be constant along the entire path of the element along the closed path, or it can be constant only in one or more elongated sections of the path. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The invention may be better understood and implemented with reference to the accompanying drawings, which show non-limiting exemplary embodiments of the invention, and in which:

[0040] Figure 1 is a perspective view of an apparatus for compression molding a concave object, viewed from above;

[0041] Figure 2 Observed from below Figure 1 A bottom-up perspective view of the device in FIG.

[0042] Figure 3 yes Figure 1 A side perspective view of the device in;

[0043] Figure 4 yes Figure 1 An enlarged perspective view of the structural details of the device in FIG.

[0044] Figure 5 yes Figure 4 A perspective view of a detail in which some parts are transparent to better illustrate the internal structure;

[0045] Figure 6 is a perspective view of another structural detail of the device, wherein some parts are transparent to better illustrate the detailed internal structure;

[0046] Figure 7a yes Figure 6 a cross-sectional side view of a detail in; and

[0047] Figure 7b It is along Figure 7a A longitudinal sectional side view taken along line AA in FIG. DETAILED DESCRIPTION

[0048] Figure 1 A device 1 for manufacturing an object made of polymer material by compression moulding is shown. The objects that the device 1 is able to manufacture may be concave objects, in particular containers, such as coffee capsules, cans, glasses, bottles or bowls. Alternatively, the device 1 may be used to manufacture a parison designed to form a container by blow moulding.

[0049] The apparatus 1 comprises dispensing means 2 for dispensing at least one polymer material. In the example shown, the dispensing means 2 comprises extrusion means 3 for dispensing a continuous extruded structure comprising one polymer material or multiple layers of polymer materials different from one another.

[0050] The extrusion device 3 may include an extrusion head 4 from which a dose "D" of polymer material emerges in a form suitable for compression molding. Specifically, the dose "D" is in a molten state or at least partially molten state, and is therefore in a semi-solid state. Thus, the dose "D" at the outlet of the extrusion head 4 (at Figure 4 ) has a predetermined temperature to keep the polymer material in a viscous form suitable for the subsequent compression molding step.

[0051] Downstream of the dispensing device 2, a die 5 extends for receiving the dose "D" and manufacturing the above-mentioned object. The die 5 is schematically shown in the form of a male punch 6 defining a surface for supporting the dose "D". The male punch 6 is configured to be coupled with a female element (not shown in the drawings) appropriately shaped to match the male punch, so as to compress the dose "D" so as to obtain the object to be manufactured. For this purpose, the dose "D" must be positioned on the punch 6 in a precise manner and always maintained at a predetermined temperature to ensure a semi-solid structure suitable for compression molding.

[0052] The dose "D" is fed from the device 2 to the mould 5 by a series of conveying elements 7 mounted in an aligned manner along the periphery of a supporting carousel 8 rotatable about a respective axis of rotation "X". The carousel 8 feeds each conveying element 7 in an advancing direction "A" and along a closed path "C" (preferably circular) passing between the dispensing device 2 and the mould 5.

[0053] Advantageously, each conveying element 7 is configured to pick up a corresponding dose “D” from the dispensing device 2 and to release it onto the punch 6 of the die 5 .

[0054] More specifically, each delivery element 7 intercepts a dose "D" emerging from the head 4 during its advancement along the path "C" in order to advance this dose towards the mold 5 ( Figure 3 ). After the dose is released onto the punch 6, the delivery element 7 moves again along the path "C" to the dispensing device 2 where it intercepts a new dose "D". Preferably, each delivery element 7 comprises a wall 9 for engaging the dose "D", which is designed to contact the dose "D" and retain it during the movement along the path "C".

[0055] The wall 9 is preferably flat and may be provided with a series of suction holes 10 (e.g. Figure 6), these suction holes facilitate the retention of the dose "D". In this case, the hole 10 is fluidly connected to a suction source configured to suck in air and accurately define a negative pressure at the wall 9 to facilitate the retention of the dose "D". The hole 10 can also be provided for blowing air to facilitate the step of removing and cutting the dose "D" from the wall 9.

[0056] In this case, after reaching the die 5 , the orifice allows the jet of air to flow towards the outside, which pushes the dose “D” so that it is separated from the wall 9 and positioned on the punch 9 .

[0057] Each conveying element 7 is also rotatably mounted on a turntable 8 and can be rotated between a pick-up state, in which a wall 9 has a contact surface 9a (e.g., 9b) in contact with the dose "D" and oriented transversely to the advancement direction "A"), and a release state in which a dose "D" is released. Figure 3 In the released state, the wall 9 is turned over and the contact surface 9a faces the mold 5 (as shown in FIG. Figure 2 ). Advantageously, in the pickup state, the wall 9 intercepts the dose "D" and removes it from the dispensing device 2, whereas in the release position, the wall 9 causes the dose "D" to fall into the mould 5.

[0058] In other words, element 7 is suitably rotated 90° by a movement system (eg a cam system mounted on a turntable) for positioning wall 9 facing dose “D” and lowering wall 9 to die 5 facing punch 6 .

[0059] It should be noted that the wall 9 has a planar extension and that, in the pickup state facing the dose "D", the wall 9 cuts the dose "D" from the rest of the extruded material by means of its upper cutting edge.

[0060] It should also be noted that the wall 9 is in the picked-up state only when it is close to the dispensing device 2, and is immediately lowered when it is close to the mold 5. For this reason, for most of the path "C" along which each element 7 moves, the wall 9 is in the released state with the flat surface 9a facing downwards. In this regard, it should be noted that the walls 9 in the released state are all positioned coplanar with each other and facing downwards.

[0061] The device 1 also comprises cooling means 11 for cooling each conveying element 7 , so as to cool the conveying element 7 at least in the region of the closed path “C”.

[0062] More specifically, according to the first embodiment of the present invention, the cooling device 11 comprises at least one blowing unit 12 located in front of the turntable for generating a cooling air flow.

[0063] like Figure 1 and Figure 2, the air flow is directed towards the walls 9 of each element 7 in the corresponding released state. In fact, in this case, the walls 9 in the released state have a planar extension facing the blowing unit 12, so that these walls can be hit by the air flow. Advantageously, the air flow cools the walls 9 upstream of the dispensing device 2, that is, before each wall 9 picks up a dose "D". Advantageously, with specific reference to Figure 2 , Figure 4 and Figure 5 The blowing unit 12 has a box-shaped collector 13 having an arcuate profile parallel to at least one elongated section “T1” of the closed path “C” between the mold 5 and the distribution device 2 in the advancing direction “A” of the conveying element 7 .

[0064] The manifold 13 has an upper surface 13a facing the conveying element 7 sliding at the elongated section T1 described above and having at least one nozzle 14 for discharging a cooling air flow.

[0065] Preferably, there are a plurality of nozzles 14 spaced apart from each other and aligned along the arcuate extension section "T1" described above, for distributing corresponding air flows in a uniform manner toward the wall 9 of the corresponding element 7 along the extension section "T1" of the closed path "C" between the mold 5 and the distribution device 2 in the advancing direction "A".

[0066] It should be noted that at the elongated section "T1" described above, the wall 9 of the element 7 is oriented in a corresponding released state ( Figure 2 ). In fact, in this case, the walls 9 of the element 7 that advances in the extension "T1" have extensions coplanar with each other and facing the upper surface 13a of the manifold 13, so that these walls can be hit by the cooling air flow. The air flow is supplied by the water heat exchanger 16 (at Figure 4 and Figure 5 The cooling (shown only schematically in the figure) is used to supply pressurized cooling air of a predetermined temperature inside the manifold.

[0067] For this purpose, the manifold 13 is advantageously provided internally with ducts 15 for the passage of cooling air, so as to put the heat exchanger 16 in fluid communication with the nozzles 14 .

[0068] The passage duct 15 includes a main branch duct 15a extending in the longitudinal direction along the manifold 13 and a series of auxiliary branch ducts 15b branching from the main duct 15a toward the corresponding nozzles 14. The main branch duct 15a is also connected to the heat exchanger 16 through an appropriate pneumatic passage (schematically shown in the drawings). In this regard, it should be noted that the pneumatic paths shown in the drawings are shown only by way of non-limiting example. Therefore, the pneumatic passage can be connected to any part of the passage duct 15.

[0069] In addition or as an alternative to the above, the cooling device 11 also comprises a duct 17 formed inside the wall 9 of each conveying element 7 for the passage of a cooling fluid.

[0070] The passage duct 17 supplies the fluid in such a way that the fluid cools the interior of the wall 9 when supplying the fluid along the circumferential path "C" and in the respective pick-up state and / or release state.

[0071] Specifically, Figure 6 , Figure 7a and Figure 7b As better shown in FIG. 1 , the passage duct 17 comprises: an inlet extension 17a configured to supply a cooling fluid from a supply source 18 toward the interior of the wall 9; an outlet extension 17b for the fluid heated inside the wall 9, the outlet extension 17b configured to make the hot fluid flow toward the exterior of the wall 9; and a plurality of heat exchange extensions 17c extending between the inlet extension 17a and the outlet extension 17b. In this way, the fluid in the exchange extension 17c absorbs the heat transferred by the wall 9, thereby reducing the temperature of the wall 9.

[0072] Thus, the cooling fluid in the inlet extension 17a is heated at the heat exchange extension 17c and then flows out of the wall 9 from the outlet extension 17b.

[0073] Advantageously, the heat exchange extensions 17c are parallel to one another and extend in a region of the wall 19 corresponding to the region for coupling the dose "D".

[0074] In other words, the heat exchange extension 17c is housed in the region 19 of the wall 9 in which the dose "D" is engaged by the wall. The region 19 is advantageously provided with the suction and / or blowing holes 10 described above. Figure 7a and Figure 7b As can be seen in the cross-sectional view in FIG. 1 , the region 19 is defined by a cavity 20 of smaller cross section in the wall 9 , where the thickness of the wall 9 is smaller to facilitate heat exchange with the cooling fluid.

[0075] Therefore, in the state where the dose "D" is picked up and held, the heat transferred from the dose "D" to the wall 9 is absorbed by the flowing fluid in the heat exchange conduit 17c, thereby controlling the temperature of the cooled wall 9.

[0076] Advantageously, the cooling fluid may be a cooling liquid.

[0077] Supply source 18 (in Figure 2 and Figure 3 17a and the outlet elongate section 17b to cool the fluid from the outlet elongate section 17b (hot) and to supply the cooled fluid to the inlet elongate section 17a.

[0078] For this purpose, the supply source 18 is formed in the turntable 8 and is only schematically shown ( Figure 1 ) is fluidly connected to the inlet extension section 17a.

[0079] In this way, during the entire closed path “C” along which the conveying element 7 moves, each channel 21 (each extending radially from the center of the turntable connected to the source towards the corresponding element 7) allows the cooling fluid to pass and flow to each inlet extension 17a formed in the corresponding wall 9.

[0080] Advantageously, the wall 9 is constantly thermally regulated and stably maintained at an optimal temperature, dissipating the heat generated by the dose "D".

[0081] according to Figure 1 In another embodiment of the invention, there is also at least one curved cavity 22 corresponding to the corresponding angular sector "T2" of the closed path "C". The arched cavity 22 is formed in a fixed area of ​​the turntable 8 so as to be always fluidically connected to the source 8 and to be selectively connected to the channel 21 only when the corresponding element 7 passes through the angular sector "T2" described above.

[0082] In other words, only when the inlet channel 21 is arranged in communication with the cavity 22, the respective channel 21 allows the cooling fluid to flow from the source 18 to the inlet extension 17a.

[0083] In this way, internal cooling of the wall 9 occurs only when the element 7 passes through the angular sector T2 and therefore only in a portion of the closed path “C”.

[0084] Preferably, there may be two or more cavities 22 for cooling each wall 9 two or more times when feeding the respective element 7 along path "C".

[0085] The position and size of each curved cavity 22 therefore determine the position and duration of the cooling effect on the wall 9 . Figure 1 By way of example, a single cavity 22 is shown, at the location of the device 2 and the mold 5 (angular sector "T2"), which cavity allows the passage of a cooling fluid. However, it should be noted that the cavity 22 may have any position or length, depending on the specific cooling function of the wall 9.

[0086] According to an alternative embodiment of the invention, the cooling device 11 may consist of a system for distributing the suction air and the blowing air to the dose "D". In this case, the suction air / blowing air passing through the holes 10 also serves for thermal regulation and provides the effect of cooling the wall 9 in the elongated section of the dose "D" situated between the mould 5 and the dispensing device 2.

[0087] The present invention also relates to a method for compression molding an object made of a polymer material. The method comprises the following steps:

[0088] - continuously dispensing by the dispensing device 2 a dose (D) of polymer material in a shape suitable for compression moulding;

[0089] - picking up a dose (D) from the dispensing device 2 using a corresponding conveying element 7 mounted on a rotating carousel 8;

[0090] - feeding the elements 7 from the dispensing device 2 to the mould 5 in the advancement direction A and along a closed path “C”;

[0091] - releasing the dose into the mould to produce a concave object;

[0092] - wherein the method further comprises the step of cooling each conveying element 7 during the step of advancing the elements 7 and at least in the zones T1 , T2 of the closed path “C”.

[0093] In particular, the step of cooling the conveying elements 7 is achieved by blowing at least one stream of air towards the wall 9 of each element 7 configured to engage and retain the dose "D".

[0094] The step of blowing an air flow is achieved by distributing a plurality of pressurized air jets positioned in an aligned manner along an arcuate extension “ T1 ” of the path “C” between the mold 5 and the distributing device 2 in the advancement direction “A” of the conveying element 7 .

[0095] When the walls 9 of the conveying element 7 are oriented in the release state for the respective release of the dose "D", an air flow is distributed to the walls. Advantageously, in the release state, the walls 9 are turned over and their planar extension is parallel to the direction of advancement "A" along the path "C". Moreover, in the release state, the walls 9 are coplanar with each other so as to face the air flow that hits the surface of each wall 9. Advantageously, it should be noted that a cooling effect is achieved upstream of the dispensing device 2 and therefore before the step of picking up the dose "D". In this way, each wall 9 is thermally conditioned (cooled) to pick up and hold the dose "D" in optimal conditions (from a thermal point of view), thereby also cooling the dose "D".

[0096] Additionally or alternatively to the above, the step of cooling the conveyor elements 7 is carried out by distributing a cooling fluid to the interior of the wall 9 of each element 7 .

[0097] In this case, the cooling heat flow does not hit the wall 9 from the outside as described above, but is distributed inside the wall 9 .

[0098] Preferably, the step of distributing the cooling fluid in the wall 9 is achieved by feeding the fluid through a plurality of heat exchange extensions 7c formed inside the wall 9 to allow the fluid to absorb heat transferred from the dose D through the wall 9 and thus reduce the temperature of the wall 9 .

[0099] According to an embodiment of the invention, a step of cooling the inside of the wall 9 is continuously performed during the advancement of the element 7 along the entire circumferential path “C” and at the respective pickup and release states of the doses “D”.

[0100] Alternatively, according to another embodiment, the step of distributing a cooling fluid in the wall 9 is carried out during at least one angular sector "T2" of the passage of each element 7 through the closed path "C". In this way, the wall 9 is cooled for a period of time that can be carried out simultaneously with the step of picking up and putting down the dose "D" or before the step of picking up the dose "D".

[0101] Therefore, the present invention overcomes the deficiencies in the prior art and brings important advantages.

[0102] Firstly, it should be noted that the wall 9 of the delivery element 7 is thermally conditioned to absorb part of the heat of the dose "D" extruded in semi-solid form.

[0103] In this way, the temperature of the cooled wall 9 enables the temperature of the dose “D” to also be reduced, so as to maintain it in any case in a semisolid state suitable for compression moulding, while avoiding adhesion to the wall 9 .

[0104] For this purpose, the cooling effect of the wall 9 (which also determines the cooling of the dose "D") facilitates the separation of the dose "D" by simply moving the wall 9 and interrupting the inhalation if necessary. The dose "D" can thus be positioned optimally and accurately on the punch 6.

[0105] Furthermore, the device is very versatile since it is able to cool the wall 9 from the outside by means of air flowing out of the manifold 13 and / or by means of internal cooling of the wall 9 .

[0106] The cooling area in the "C" path may also be determined according to specific requirements, the properties of the polymer material and the tendency of the material to adhere to the wall 9 in the molten state.

Claims

1. A device comprising: - a dispensing device (2) for dispensing a dose (D) of polymer material in a shape suitable for compression moulding; - a mold (5) for receiving said dose (D) and producing a concave object; - a plurality of conveying elements (7) for conveying respective doses (D), each of said plurality of elements being configured to pick up a respective dose (D) from said dispensing device (7) and to release it onto said mould (5); - a turntable (8) for supporting the conveying elements (7), the turntable being used to feed each conveying element (7) in an advancing direction (A) and along a closed path (C) passing between the dispensing device (2) and the mould (5) in order to move the dose (D) to the mould (5); - wherein each of the conveying elements (7) comprises a wall (9) for engaging the dose (D), each of the conveying elements (7) being rotatably mounted on the turntable (8) and being rotatable between a pick-up state and a release state in which the dose (D) is released, wherein in the pick-up state the wall (9) has a corresponding contact surface (9a) transverse to the advancement direction (A) for contacting the dose (D) to intercept and pick up the dose (D) from the dispensing device (2), and in the release state the wall (9) is turned over and the contact surface (9a) faces the mould (5) to release the dose (D) into the mould (5) by the action of gravity; - wherein the device comprises a cooling device (11) for each of the conveying elements (7) for cooling the conveying element (7) at least in a region (T1, T2) of the closed path (C).

2. The device according to the preceding claim, wherein: The cooling device (11) comprises at least one blowing unit (12) for blowing a cooling air flow, so as to guide the flow towards the wall (9) in the corresponding released state; the wall (9) in the released state has a planar extension, which faces the blowing unit (12) so as to be cooled by the blowing unit (12) upstream of the distribution device (2).

3. The device according to the preceding claim, wherein The blowing unit (12) has a manifold (13) having an arc-shaped extension parallel to at least one elongated section (T1) of the closed path (C) between the mold (5) and the distribution device (2) in the advancement direction (A) of the conveying element (7); the manifold (13) has at least one nozzle (14) for discharging a cooling air flow toward the wall (9).

4. Device according to the preceding claim, wherein The manifold (13) has a plurality of nozzles (14) spaced apart from one another for distributing respective air flows along the elongated section (T1) of the closed path (C) between the mould (5) and the distributing device (2), wherein the wall (9) is in a respective released state.

5. Device according to the preceding claim, wherein The cooling device (11) comprises a water heat exchanger (16) for cooling air, located upstream of the manifold (13); the manifold (13) has a pipe (15) inside for passing cooling air, so that the heat exchanger (16) is in fluid communication with the nozzle (14).

6. Apparatus according to any preceding claim, wherein: The cooling means (11) comprise a plurality of holes (10) formed in the contact surface (9a) for aspirating and / or blowing the dose (D); during aspirating and / or blowing the dose (D), the holes allow air to pass through to cool the wall (9).

7. Apparatus according to any preceding claim, wherein: The cooling device (11) comprises a channel duct (17) formed inside the wall (9) for passing a cooling fluid, for cooling the wall (9) along the circumferential path (C) and in the respective pick-up state and / or release state.

8. Device according to the preceding claim, wherein The channel pipe (17) includes: an inlet extension section (17a) for supplying a cooling fluid from a source (18) to supply the fluid to the inside of the wall (9); an outlet extension section (17b) for the fluid heated inside the wall (9) to flow out toward the outside of the wall (9); and a plurality of heat exchange extension sections (17c) extending between the inlet extension section (17a) and the outlet extension section (17b); the fluid in the heat exchange extension section (17c) absorbs the heat transferred from the dose (D) to reduce the temperature of the wall (9).

9. Device according to the preceding claim, wherein The heat exchange elongated sections (17c) are parallel to each other and extend in the region (19) of the wall (9) in contact with the dose (D).

10. The device according to claim 8, wherein: The supply source (18) comprises a water heat exchanger in fluid communication with the inlet extension (17a) and the outlet extension (17b) for cooling the fluid flowing out of the outlet extension (17b) and supplying the cooled fluid to the inlet extension (17a).

11. The device according to claim 8, wherein: The supply source (18) is in fluid communication with the inlet extension (17a) via a channel (21) formed in the turntable for supplying cooling fluid; the channel (21) allows the cooling fluid to pass through and flow to the inlet extension (17a) during the entire path (C) of the conveying element (7).

12. The device according to claim 8, wherein: The supply source (18) is in fluid communication with the inlet extension (17a) via a supply channel (21) formed in the turntable for supplying cooling fluid; wherein the supply channel has at least one curved cavity (22) corresponding to a corresponding angular sector (T2) of the path (C); the supply channel (21) allows the cooling fluid to pass through and flow toward the inlet extension (17a) only when the element (7) is located in the angular sector (T2) of the closed path (C).

13. A method comprising: - continuously dispensing a dose (D) of polymer material in a shape suitable for compression moulding by a dispensing device (2); - picking up the dose (D) from the dispensing device (2) using a corresponding conveying element (7) mounted on a rotating carousel (8); - feeding the conveying element from the distribution device (2) to the mould (5) in an advancing direction (A) and along a closed path (C); - releasing said dose (D) into said mould (5) in order to produce a concave object; - wherein the method further comprises the step of cooling each of the conveying elements (7) during the step of advancing the conveying elements (7) and at least in a region (T1, T2) of the closed path (C).

14. The method according to the preceding claim, wherein: The step of cooling the conveying elements (7) is achieved by blowing at least one air flow towards a wall (9) of each conveying element (7) configured to engage the dose (D).

15. The method according to the preceding claim, wherein: The step of blowing the air flow is achieved by distributing a plurality of pressurized air jets, wherein these pressurized air jets are aligned along an arcuate extension (T1) of the path (C) between the mold (5) and the distribution device (2) in the advancement direction (A) of the conveying element (7).

16. The method according to the preceding claim, wherein: An air flow is distributed to the wall (9) of the conveying element (7) in a release state oriented to release the dose (D), in which the wall (9) is turned over and its planar extension is parallel to the advancement direction (A).

17. The method according to any one of claims 13 to 16, wherein: The step of cooling the delivery elements (7) is achieved by distributing a cooling fluid to the interior of a wall (9) of each delivery element (7) configured to engage the dose.

18. The method according to the preceding claim, wherein: The cooling step is carried out during the advancement of the conveying element (7) along the circumferential path (C) and in the respective pick-up state and / or release state.

19. The method according to the preceding claim, wherein: The step of distributing a cooling fluid in the wall (9) is achieved by feeding the fluid through a plurality of heat exchange elongates (7c) formed inside the wall (9) to allow the fluid to absorb heat transferred from the dose (D) and reduce the temperature of the wall (9).

20. The method according to claim 18 or 19, wherein: During the entire closed path of each of said conveying elements (7), a step of distributing a cooling fluid in said wall (9) is carried out.

21. The method according to claim 18 or 19, wherein: During the passage of each of said conveying elements (7) through at least one angular sector (T2) of said path (C), a step of distributing a cooling fluid in said wall (9) is carried out.

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