Cooling and holding pins of a device for cooling and handling preforms made of plastic material

Abstract

A cooling and holding pin (1) for cooling plastic preforms by air blowing and for holding plastic preforms by air suction, the pin comprising: a body (2) defining a longitudinal axis and having a first opening (5) at a first end of the body, the first opening being coaxial with the longitudinal axis and being suitable for connection to a processing station; a movable element (3) being suitable for sliding at least partially within the body; at least one air channel gap being arranged at the second end of the body or at the first end; wherein the movable element (3) is suitable for moving from a first position corresponding to a first air channel cross section to a second position corresponding to a second air channel cross section, the second cross section being smaller than the first cross section, thereby adjusting the blowing air flow during the cooling step and adjusting the suction air flow during the step of holding the preform.

Description

Field of the Invention

[0001] The invention relates to a cooling and holding nozzle or pin in a device for cooling and handling preforms made of plastic material, which is particularly suitable for completing the cooling of preforms that have just been molded and extracted from an injection mold by a removal plate or a removal device, and for extracting the cooled preforms from said removal device or another intermediate holding device. The preforms are then intended to be transformed into containers, in particular bottles or cans, by a blow molding or stretch blow molding method. The invention also relates to: a processing station, which includes a plurality of cooling and holding pins and is suitable for cooperating with a plate for extracting preforms from the injection mold; a preform cooling and handling device, which includes said processing station; an injection molding machine including said device; and a related method for handling and cooling preforms. Background Art

[0002] A preform is a semi-finished product made of thermoplastic material for the manufacture of a container which in turn is obtained by a subsequent blow-molding or stretch-blow-molding process. Preforms are obtained by different methods, for example by injection or injection-compression molding or extrusion in combination with a further thermoforming operation. In the production of containers made of plastic material, such as bottles, preforms are usually obtained by injection molding with a mold provided with a plurality of cavities.

[0003] Typically, in most injection molding processes, the step that involves the main consumption of time is that of cooling the molded object. Said cooling step takes place inside the mold, more precisely inside the mold cavity, until the molded object is sufficiently hard to be removed from the mold itself, and then handled and transported. Obviously, before the molded object has cooled sufficiently and therefore solidified, it is not possible to release the mold cavity and continue the production cycle with a new molding step. Therefore, in order to reduce the time of the entire molding cycle, and therefore to increase the productivity of the molding station, various devices have been developed that are able to perform at least a portion of the cooling of the preform outside the injection mold.

[0004] Systems for removing preforms from injection moulds are currently equipped with cooling circuits. As mentioned above, said cooling circuits allow reducing the production cycle time; in fact, the time that the preforms must remain inside the injection mould can be reduced if the removal system is equipped with a cooling circuit. Such removal systems generally comprise a preform extraction plate suitable for extracting the preforms from the injection mould while cooling them for a predetermined period of time, and this is achieved by the circulation of a suitable fluid inside the extraction plate itself.

[0005] Such an extraction plate, also called "post-moulding equipment" or "take-out plate" or "end-of-arm tooling" (EOAT), is provided with a plurality of cooling shells, also called tubes, but also called "cooling tubes", "take-out tubes" or "cooling sleeves".

[0006] Whatever the method and apparatus used to extract the preform from the injection mold, the cooling of the molded preform that begins in the mold cavity of the mold continues in the cooling shell of the extraction plate.

[0007] Downstream of the extraction plate, at least one additional cooling and treatment device is provided, which cooperates upstream with said extraction plate and downstream with other components of the production facility.

[0008] However, the cooling and treatment devices of the prior art are not very effective. Some of them use air sucked from inside the compartment of the injection molding machine for further cooling. Therefore, the air used for this cooling is relatively warm, usually at a temperature of 30-35° C., and therefore does not ensure optimal cooling.

[0009] One known example of such an apparatus uses a rotary processing station, also called "rotating housing", which is dedicated to suction during the cooling step and during the steps of holding the preforms and extracting them from an extraction plate.

[0010] Disadvantageously, the suction does not allow effective cooling to be obtained due to the limited air flow rates that can be achieved with the current cooling and holding pins. Furthermore, the suction during the step of further cooling of the preforms means that the hot air of the compartment is sucked directly inside the preforms and then enters the "rotating housing" after passing through the corresponding pins of the rotary processing station.

[0011] Another disadvantage of current cooling and holding pins is that they do not allow easy extraction and handling of preforms, in particular for heavy preforms, since the vacuum created inside the preform during suction generally does not ensure an optimal grip, causing some preforms to fall out during the extraction and handling steps.

[0012] Therefore, there is a need to produce a preform cooling and retaining pin that can overcome the above-mentioned disadvantages. SUMMARY OF THE INVENTION

[0014] The object of the present invention is to provide a preform cooling and handling pin which allows to effectively regulate the airflow for cooling the preforms and the airflow for extracting and handling the preforms, the pin being configured to blow air during the cooling step and to suck air during the extraction and handling step.

[0015] Another object of the invention is to provide a cooling and handling pin capable of obtaining a high air flow rate during the blowing step, for better cooling of the preforms, and a high vacuum inside the preforms during the suction step, thus ensuring better handling and extraction of the preforms, even for those preforms whose combination of weight and geometry makes the above-mentioned operation critical.

[0016] Another object of the present invention is to provide a cooling and handling pin which allows further optimization of the preform cooling time and therefore of the injection molding cycle time, while ensuring high quality preforms for perfect molding of the blow molded containers.

[0017] Therefore, the present invention aims to achieve the above-mentioned object and provides a cooling and holding pin for cooling by air blowing and holding a preform made of plastic material by air suction, the pin comprising:

[0018] - a body defining a longitudinal axis and having a first opening at a first end of the body, the first opening being coaxial with said longitudinal axis and being adapted to be connected to a processing station;

[0019] - a movable element adapted to slide at least partially within said body;

[0020] at least one gap for the passage of air during the blowing step and the suction step, the gap being provided at the second end of the body, or at said first end, the second end being opposite to the first end;

[0021] wherein the movable element is adapted to move from a first position corresponding to a first cross-section of the passage for air passing through the at least one gap to a second position corresponding to a second cross-section of the passage for air passing through the at least one gap, the second cross-section being smaller than the first cross-section, thereby adjusting the blowing airflow in the first position during the cooling step and adjusting the suction airflow in the second position during the step of holding the preform.

[0022] Another aspect of the invention relates to a processing station for processing plastic preforms and adapted to cooperate with an extraction plate adapted to extract the preforms from an injection mould, the processing station comprising a housing defining an internal volume communicating on one side with a plurality of cooling and retaining pins (such as those described above) and adapted to communicate on the other side with an aeraulic circuit,

[0023] wherein the housing has at least one surface provided with said plurality of cooling and retaining pins,

[0024] wherein a first end of the body of each pin having a first opening is arranged within the housing,

[0025] And wherein the second end of the body of each pin is disposed outside the housing.

[0026] Another aspect of the present invention relates to a device for processing and cooling plastic preforms, comprising a processing station as described above and a ventilation circuit connected to the processing station, wherein the ventilation circuit comprises: an intake duct for sucking air from the interior of the processing station; a conveying duct for delivering air to the processing station; a cooling device arranged along the conveying duct for cooling the air delivered to the processing station; and wherein a switching device for the ventilation circuit is also provided to switch from a first circuit configuration to a second circuit configuration, in which an air passage from the conveying duct to the processing station is possible, and in which an air passage from the processing station to the intake duct is possible, so that in the first circuit configuration air can be blown through multiple cooling and retaining pins, while in the second circuit configuration air can be sucked through multiple cooling and retaining pins.

[0027] Another aspect of the present invention relates to an injection molding machine, comprising a housing, in which at least: at least one injection mold, which includes a plurality of mold cavities; at least one extraction plate, which includes at least one group of cooling shells, the cooling shells are suitable for receiving and holding at least one group of preforms extracted from the mold cavities, the cooling shells are suitable for removing a first amount of thermal energy from the preforms by conduction; and a device for processing and cooling plastic preforms as described above; wherein the processing station is configured to change from a loading position for cooperating with the extraction plate to an unloading position for releasing the preforms from cooling and holding pins, wherein, in the loading position, the cooling and holding pins of the processing station are suitable for cooperating with the corresponding cooling shells of the extraction plate to remove a second amount of thermal energy from the preforms during the step of blowing air through the pins when the ventilation circuit is in the first circuit configuration, and then to hold the preforms and extract the preforms from the cooling shells during the step of drawing air through the pins when the ventilation circuit is in the second circuit configuration.

[0028] Another aspect of the invention relates to a method for handling and cooling plastic preforms, carried out in the aforementioned injection molding machine, comprising the following steps:

[0029] arranging a treatment station in a loading position, the treatment station being arranged facing an extraction plate containing at least one group of preforms in a respective cooling housing, and arranging the ventilation circuit in a first circuit configuration;

[0030] inserting cooling and holding pins of the processing station into corresponding cooling housings and further cooling the preforms contained in the cooling housings by blowing air through the pins having the movable element in the first position;

[0031] switching the ventilation circuit from the first circuit configuration to the second circuit configuration by means of a switching device and drawing air through the pins so that the movable element is in the second position to hold the preform on the processing station;

[0032] disengaging the cooling and retaining pins from the respective cooling housings, continuing to draw air through the pins with the movable element in the second position;

[0033] moving the processing station from a loading position to an unloading position, continuing to draw air through the pins, wherein the movable element is in a second position;

[0034] The ventilation circuit is switched from the second circuit configuration to the first circuit configuration by means of the switching device, and air is blown through the pins to release the preforms from the pins.

[0035] Advantageously, the cooling and retaining pin of the invention allows obtaining, in particular by means of the regulation of the blowing air flow and the regulation of the suction air flow:

[0036] - more efficient cooling of the preforms by blowing, thanks to better heat exchange;

[0037] - A higher efficiency is also achieved in the extraction step by suction, ensuring a suction flow rate which avoids any risk of the preforms falling once they have been extracted from the extraction plate.

[0038] The regulation of the blowing flow and the suction flow is performed by moving the movable element between two different working positions.

[0039] Advantageously, the movable element is configured to modify the geometry of the air passage section of at least one gap or at least one hole provided at one of the two ends of the pin. By modifying the air passage section, the pressure drop characteristic curve of the ventilation system changes, passing from a maximum passage section (during the step of blowing air into the preform when the movable element is in the first position) to a minimum passage section (during the step of sucking air from inside the preform when the movable element is in the second position). Thus, a high air flow rate will be obtained during the blowing step, for better cooling of the preform, and a high vacuum will be obtained inside the preform during the suction step, thus ensuring better handling and extraction of the preforms, even for those preforms whose combination of weight and geometry makes the above-mentioned operation critical.

[0040] In a first advantageous variant of the invention, at least one hole, the passage section of which has to be adjusted, is provided on the movable element or the valve itself, at the tip of the pin, ie at its distal end relative to the housing of the treatment station.

[0041] In a second advantageous variant of the invention, at least one hole, the passage cross section of which has to be adjusted, is provided on said distal end of the pin and a movable element or valve is provided at said distal end or tip of the pin.

[0042] In the first and second variants, the valve preferably moves within a sleeve fastened to the body of the pin, the sleeve serving as end-of-travel piece of the valve.

[0043] In a third advantageous variant of the invention, at least one hole, the passage cross section of which must be adjusted, is provided on the distal end with the pin, and the movable element or valve provided at the distal end or tip of the pin is provided in its first extension with at least one first hole of a first size, and in its second extension with at least one second hole of a second size smaller than the first size, whereby, when the movable element is in the first position, only the at least one first hole of the valve communicates with the at least one hole of the pin, and when the movable element is in the second position, only the at least one second hole of the valve communicates with the at least one hole of the pin. In this case, a sliding bushing in which the movable element slides is provided in the distal end of the pin. The movable element has at its ends a first end-of-stroke element and a second end-of-stroke element, respectively, the first end-of-stroke element resting against an internal shoulder of the body of the pin when the movable element is in the first position and the second end-of-stroke element resting against the distal end of the pin when the movable element is in the second position.

[0044] In other advantageous variants of the invention, at least one hole, the passage cross section of which must be adjusted, is provided on the side surface of the pin head, i.e. at the proximal end of the pin relative to the housing of the operating station. In this case, a movable element or valve is provided at said proximal end of the pin, closing an opening coaxial with the longitudinal axis.

[0045] In another advantageous variant of the invention, only one gap is provided, coaxial with the longitudinal axis, the passage cross section of which has to be adjusted. The movable element or valve moves from a first position, in which the gap is defined between a smaller-sized portion of the movable element and the opening of the distal end or tip of the pin, to a second position, in which the gap is defined between a larger-sized end of the movable element and said opening of the tip of the pin. Said opening of the tip of the pin is penetrated by the movable element.

[0046] In all variants of the invention, the passage of the movable element from the first position to the second position and vice versa allows the air passage section for the blowing and suction steps to be adjusted.

[0047] The dependent claims describe particular embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Further features and advantages of the invention will become more apparent from the detailed description of a preferred but not exclusive embodiment of a preform cooling and holding pin, illustrated by way of non-limiting example with the aid of the accompanying drawings, in which:

[0050] Figure 1ashows a perspective view of an injection molding machine comprising an example of a processing station provided with a plurality of cooling and holding pins according to the invention;

[0051] Figure 1b Shows Figure 1a A perspective view of a portion of the machine;

[0052] Figure 2a shows an exploded view of a first embodiment of a pin according to the invention;

[0053] Figure 2b and Figure 2c Shows Figure 2a A perspective view of the pin in two operating positions;

[0054] Figure 3a and Figure 3b Shows Figure 2a A cross-sectional view of the pin in two operating positions;

[0055] Figure 4a shows an exploded view of a second embodiment of a pin according to the invention;

[0056] Figure 4b Shown in operating position Figure 4a A perspective view of the pin in FIG.

[0057] Figure 4c Shows Figure 4b A partial transparent perspective view of the details of the pin in FIG.

[0058] Figure 4d Shows Figure 4b A perspective view of a component of a pin in FIG.

[0059] Figure 5a and Figure 5b Shows Figure 4a A cross-sectional view of the pin in two operating positions;

[0060] Figure 6a shows an exploded view of a third embodiment of a pin according to the invention;

[0061] Figure 6b Shown in operating position Figure 6a A perspective view of the pin in FIG.

[0062] Figure 7a and Figure 7b Shows Figure 6a A cross-sectional view of the pin in two operating positions;

[0063] Figure 8a shows an exploded view of a fourth embodiment of a pin according to the invention;

[0064] Figure 8b Shown in operating position Figure 8a A perspective view of the pin in FIG.

[0065] Figure 9a and Figure 9b A front view and a rear view, respectively, show a plate of a processing station provided with pins according to said fourth embodiment;

[0066] Fig.10a and Fig.10b Shows Figure 8a A cross-sectional view of the pin in two operating positions;

[0067] Fig.11a shows an exploded view of a fifth embodiment of a pin according to the invention;

[0068] Fig.11b Shown in operating position Fig.11a A perspective view of the pin in FIG.

[0069] Fig.12a and Figure 12b A front view and a rear view, respectively, show a plate of a processing station provided with pins according to said fifth embodiment;

[0070] Fig.13a and Fig.13b Shows Fig.11a A cross-sectional view of the pin in two operating positions;

[0071] Fig.14 shows a perspective cross-sectional view of a sixth embodiment of a pin according to the invention;

[0072] Fig.15a and Fig.15b Shows Fig.14 A cross-sectional view of the pin in two operating positions;

[0073] Fig.16 shows a side view of a seventh embodiment of a pin according to the invention;

[0074] Fig.17 Shown along Fig.16 A cross-sectional view of the plane AA of the pin in FIG.

[0075] Fig.18a and Fig.18b shows the two operating positions Fig.17 Details of the pin in the cross section;

[0076] Fig.19 Shows Fig.17 A perspective view of a component of a pin in FIG.

[0077] Fig. 20 Shows Fig.19A front view of a component;

[0078] Fig.21 Shows Fig.19 A side view of a component in FIG.

[0079] Fig. 22 Shown along Fig.21 Sectional view of the plane BB of the middle component.

[0080] The same reference numerals in the drawings denote the same elements or components.

[0081] Detailed description of the preferred embodiment of the present invention

[0082] refer to Figure 1a , the injection molding machine 23 is shown to include a compartment 21, in which at least:

[0083] - at least one injection mold 22, comprising a plurality of mold cavities;

[0084] - an injection unit 24 for injecting molten plastic into the injection mold 22 to fill the mold cavity;

[0085] at least one extraction plate 500 comprising at least one set of cooling shells 13 for receiving and holding at least one set of preforms extracted from the mould cavity in a known manner; said cooling shells 13 being configured to carry out a first cooling of the preforms after extraction from the mould;

[0086] - and cooling and treatment equipment 100.

[0087] The cooling shells 13 have a generally tubular shape, or in any case a hollow shape, fastened to a suitable frame or housing for supporting the extraction plate 500, aligned according to two spatial directions and arranged in rows and columns, thus forming a matrix. Inside each cooling shell 13, a seat is obtained, the geometry of which reproduces the shape of the outer surface of the preform. By means of an insertion opening, the preform to be cooled can be introduced into each seat.

[0088] The space inside the frame and cooling housing 13 is traversed by a cooling fluid such as water and / or air to cool the preforms inserted into the housing. Multiple internal channels in the extraction plate and housing allow the cooling fluid to flow along appropriate paths to lap and cool the various tubular bodies of the cooling housing.

[0089] refer to Figure 1b, shows a cooling and treatment device 100 for cooling and treating preforms for producing containers, in particular bottles, which are made of thermoplastic materials, such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PLA (polylactide or polylactic acid) or other further and suitable materials, and mixtures thereof, by subsequent blow molding or stretch blow molding of the preheated preforms.

[0090] This preform cooling and handling apparatus 100 comprises:

[0091] a treatment station 20 of the rotary type or of the only linear movement type, provided on at least one of its faces 14 with a plurality of nozzles or pins 1 for cooling and holding the preforms and adapted to cooperate with an extraction plate 500;

[0092] A ventilation circuit 50 connected to the treatment station 20 .

[0093] Analogously to the cooling housings 13 in the extraction plate 500 , the cooling and holding pins 1 are also correspondingly fastened to the surface 14 of the treatment station 20 , aligned in two spatial directions and arranged in rows and columns, thus forming a matrix.

[0094] The pin 1 communicates with the internal volume of the treatment station 20 delimited by the housing and thus with the ventilation circuit 50 .

[0095] The ventilation circuit 50 comprises:

[0096] - a suction duct 60 for sucking air from the internal volume of the treatment station 20;

[0097] - a delivery duct 70 for delivering air to said internal volume;

[0098] and a suction device 90 connected to the suction duct 60 and the delivery duct 70 .

[0099] The internal volume of the treatment station 20 is defined by a single volume or space, communicating on one side with the ventilation circuit 50 and on the other side with all the pins 1. Air can only be introduced into said single volume, on one side of the ventilation circuit 50, through a delivery duct 70, which is located outside the treatment station 20, with the result that the air is blown through all the pins 1, or it can only be sucked from said single volume through a suction duct 60, which is also outside the treatment station 20, with this suction causing the air to flow from all the pins 1 to the internal volume.

[0100] Advantageously, a cooling device 80 , such as a heat exchanger, is arranged along the conveying duct 70 to cool the air sent to the treatment station 20 .

[0101] A switching device for the ventilation circuit is provided to change from a first circuit configuration (in which there is a passage of air from the delivery duct 70 to the interior of the processing station 20) to a second circuit configuration (in which there is a passage of air from the interior of the processing station 20 to the suction duct 60), whereby in the first circuit configuration, air can be blown through all the pins of the plurality of cooling and retaining pins 1, while in the second circuit configuration, air can be sucked through all the pins of the plurality of pins 1.

[0102] Said switching means of the ventilation circuit comprise at least one valve 25 and actuating means 26 suitable for actuating said at least one valve.

[0103] The actuating means 26 actuating at least one valve 25 are independent of the actuating means (not shown) actuating the rotation or translation of the treatment station 20 , thus allowing the blowing mode or the suction mode to be selected regardless of the position and movement of the treatment station 20 .

[0104] The processing station 20 is configured to be transferred in turn from a loading position for cooperating with the extraction plate 500 , to an unloading position for releasing the preforms from the cooling and holding pins 1 .

[0105] In the loading position, the face 14 is arranged parallel to the extraction plate 500 and the cooling and holding pins 1 are adapted to cooperate with the corresponding cooling housing 13. By accessing the extraction plate 500 and the face 14, the pins 1 are inserted into the preforms arranged in the cooling housing 13 to perform a second cooling of the preforms during the air blowing step when the ventilation circuit is in the first circuit configuration, and then to hold the preforms and to extract the preforms from said cooling housing 13 during the air suction step when the ventilation circuit is in the second circuit configuration.

[0106] In the first circuit configuration, the suction device 90 is adapted to draw air from the inner environment of the compartment 21 , whereas in the second circuit configuration, the suction device 90 is adapted to draw air from the interior of the treatment station 20 .

[0107] In an alternative solution not shown, the suction duct 60 and the delivery duct 70 are not in communication, and the first suction device is arranged at one end of the suction duct 60 and the second suction device is arranged at one end of the delivery duct 70, the ends being far from the treatment station 20. In particular, the first suction device may consist of a first fan or a blower configured to draw air from the internal environment of the compartment 21 when the valve 25 is in the first position, and when the valve 25 is in the second position, it is suitable for drawing air from the interior of the treatment station 20. The second suction device may consist of a second fan or a blower configured to draw air from the internal environment of the compartment 21 to deliver the air to the delivery duct 70 and then to the treatment station 20 when the valve 25 is in the first position, or to the internal environment of the compartment 21 again after cooling the drawn air by the cooling device 80.

[0108] Advantageously, all embodiments of cooling and retaining the pin 1 comprise:

[0109] a body 2 defining a longitudinal axis and having, at a first end thereof, a first opening 5 coaxial with said longitudinal axis and suitable for being connected to a processing station 20;

[0110] - a movable element 3, 3', 3", 30, 300, 301 adapted to slide at least partially inside the body 2;

[0111] - at least one gap or opening for the passage of air, provided at the second end or at the first end of the body 2;

[0112] The movable element 3, 3', 3", 30, 300, 301 can be moved from a first position corresponding to a first cross-section of the passage for air passing through the gap to a second position corresponding to a second cross-section of the passage for air passing through the gap, the second cross-section being smaller than the first cross-section, thereby adjusting the blowing airflow during the preform cooling step and adjusting the suction airflow during the preform holding step.

[0113] exist Figures 2a to 13b In the illustrated embodiment, the at least one gap is at least one hole provided at the second end or the first end of the body 2 .

[0114] In particular, only one hole or at least two holes 4, 4', 4", 40 are provided, which are arranged along a circumference coaxial with the longitudinal axis x. The movable element 3, 3', 3", 30 moves from a first position or blowing position, corresponding to a first air passage cross-section of the only one hole or each hole, to a second position or suction position, corresponding to a second air passage cross-section for the only one hole or each hole, which is smaller than the first cross-section, thereby adjusting the air flow rate blown or sucked through the only one hole or the at least two holes 4, 4', 4", 40. In all embodiments, in the case of a single hole, the single hole is generally in the shape of an annular slit, that is, the hole is a curved hole arranged along a circumference coaxial with the axis of the main body 2, but the curved axis of the curved hole does not complete the circumference.

[0115] like Figures 2a to 3b As shown, a first embodiment of the cooling and retaining pin according to the invention provides for obtaining a single hole or at least two holes 4 on the movable element 3, which are arranged at the second end of the body 2, i.e. the tip of the pin. In particular, a single hole or at least two holes 4 are obtained in the side surface of the movable element 3.

[0116] In the example shown, four holes 4 are provided, each hole 4 preferably defining an axis inclined at an angle other than zero with respect to the longitudinal axis of the body 2. The number of holes 4 may be less than or even greater than four.

[0117] In particular, the body 2 of the pin comprises a first tubular portion 2' or main part comprising a first opening 5 connected to a first end of the processing station 20. The second end of the body 2, opposite to the first end, is provided with a second tubular portion 6 in the form of a sleeve defining an end-of-travel element in which the travel of the movable element 3 from the second position to the first position is defined. The second tubular portion or sleeve 6 is fastened to the end of the first tubular portion 2' remote from the first opening 5.

[0118] In the example shown ( Figure 3a and Figure 3b ), the movable element 3, preferably of substantially cylindrical hollow shape, has:

[0119] a first end 31 , which is close to the first tubular portion 2 ′ and inside the sleeve 6 , said first end being open and communicating with the cavity of the first tubular portion 2 ′;

[0120] a second end 32 remote from the first tubular portion 2 ′ and outside the sleeve 6 , said second end being closed so as to prevent the air flow from directly hitting the bottom of the preform in the case of blowing;

[0121] A central portion 33 between the first end 31 and the second end 32 , provided with holes 4 , close to said second end 32 and arranged along a circumference coaxial with the longitudinal axis of the body 2 .

[0122] Advantageously, the first end 31 defines a shoulder of the movable element 3 adapted to abut against an internal shoulder 34 ( Figure 3a , Figure 3b ), the internal shoulder 34 serves as the end of travel.

[0123] During the air blowing from the first opening 5 toward the second end of the body 2, the movable element 3 is in the first position ( Figure 2c and Figure 3a ) or advanced position, the hole 4 is mainly located outside the body 2, preferably completely outside the sleeve 6. In this advanced position, the shoulder of the movable element 3 abuts against the internal shoulder 34 of the sleeve 6.

[0124] When the configuration of the ventilation circuit 50 is changed, the air suction from the hole 4 towards the first opening 5 of the body 2 pushes the movable element 3 to the second position ( Figure 2b and Figure 3b) or retracted position, in which the hole 4 is placed mainly in the body 2, ie almost completely in the sleeve 6. In this retracted position, the first end 31 of the movable element 3 abuts against the first tubular portion 2' of the body 2.

[0125] By changing the configuration of the ventilation circuit 50 again, the air blown from the first opening 5 of the body 2 to the hole 4 pushes the movable element 3 to the first position ( Figure 2c and Figure 3a ).

[0126] As is clearly shown in the figure, during the step of cooling the preform, air is blown through the pins 1 ( Figure 3a ), the cross section of the air passage through the hole 4 is maximum, not blocked or minimally blocked by the sleeve 6. This allows effective cooling of the preform. On the other hand, during the step of holding the preform, by sucking air through the pin 1 ( Figure 3b ), the air passage cross section through the holes 4 is minimal and is largely but only partially blocked by the sleeve 6. This allows a greater vacuum to be generated, thereby effectively extracting the preforms from the corresponding cooling shell 13 of the extraction plate 500 and holding them on the processing station 20.

[0127] like Figures 4a to 5b As shown, the second embodiment of the cooling and retaining pin according to the present invention provides a single hole or at least two holes 4' formed on the second end of the body 2 or the tip of the pin. In particular, a single hole or at least two holes 4' are obtained in the side surface of the second end of the body 2.

[0128] In the example shown, four holes 4' are provided, each hole 4' preferably defining an axis inclined at an angle other than zero with respect to the longitudinal axis of the body 2. The number of holes 4' may be less than or even greater than four.

[0129] In particular, the body 2 of the pin comprises a first tubular portion 2 ′ or main portion comprising a first opening 5 connected to a first end of the body 2 of the processing station 20 .

[0130] The second end of the body 2, opposite to the first end, is provided with the aforementioned holes 4' at an end 35 of the first tubular portion 2' remote from the first opening 5, the holes 4' being arranged along a circumference coaxial with the longitudinal axis of the body 2. Said second end of the body 2 comprises a second tubular portion 6' in the form of a sleeve, which defines an end-of-travel element defining therein the travel of the movable element 3' from the second position to the first position and vice versa. The second tubular portion or sleeve 6' is fastened to said end 35 of the first tubular portion 2' in the outermost position relative to the position of the holes 4' along the longitudinal axis of the body 2.

[0131] In the example shown ( Figure 4c , Figure 4d , Figure 5a and Figure 5b ), the movable element 3' can slide in the body 2 at the second end of the body 2, and comprises:

[0132] - a first portion 37 which is close to the orifice 4 ′ and completely inside the first tubular portion 2 ′;

[0133] and a second portion 38 remote from the orifice 4' and at least partially outside said first tubular portion 2'.

[0134] The first portion 37 includes a first end 39 adjacent to the second portion 38, a central portion 57, and a second end 41 distal to the second portion 38. The second portion 38 includes a first extension 43 adjacent to the first end 39 of the first portion 37 and a second extension 44 distal to the first end 39.

[0135] The first end 39 of the first portion 37 is substantially cylindrical and has a larger diameter than the first extension 43 of the second portion 38 so as to define a shoulder 42 of the movable element 3′ adapted to move the movable element 3′ from the second position ( Figure 5b ) moves to the first position ( Figure 5a ) abuts against a first internal shoulder of the sleeve 6 ′, which is defined by an internal protrusion 36 of the sleeve 6 ′.

[0136] The diameter of the second extension 44 of the second portion 38 is also greater than the diameter of the first extension 43, thereby defining a shoulder 45 of the movable element 3', which shoulder 45 is suitable for the movable element 3' to move from the first position ( Figure 5a ) moves to the second position ( Figure 5b ) when abutting against a second internal shoulder of the sleeve 6' defined by the aforementioned internal protrusion 36, the second internal shoulder being located on a surface opposite to the surface forming the first internal shoulder.

[0137] The first end 39 of the first portion 37 has a larger diameter than the central portion 57, which is also preferably cylindrical.

[0138] The diameter of the first end 39 allows said first end 39 to slide on part of the inner surface of the first tubular portion 2', in particular on the portion comprising the hole 4'.

[0139] A connecting extension 46 may be provided between the first end 39 and the central portion 57 .

[0140] The second end 41 of the first portion 37 preferably has a larger dimension than the central portion 57 .

[0141] Preferably, but not necessarily, the second end 41 has a larger diameter than the central portion 57. In addition, the outer surface of the second end 41 is shaped to have two curved surfaces connected by two flat surfaces. Such curved surfaces are generally two opposite parts of a cylinder coaxial with the first tubular portion 2'.

[0142] In more detail, the second end 41 is in the shape of a cylinder, coaxial with and inside the first tubular portion 2', said cylinder being cut by at least one plane parallel to the longitudinal axis of the body 2 and not containing the aforementioned longitudinal axis. Figure 4d In the example of the embodiment of the present invention, the second end 41 is in the shape of a cylinder cut by two planes parallel to each other and the longitudinal axis of the body 2, defining a hammer shape together with the central portion 57. The diameter of the cylindrical side portion of the second end 41 may be equal to the diameter of the first end 39. Many other shapes may be designed for the second end 41, as long as they allow air to flow from the first opening 5 to the hole 4', or allow air to flow from the hole 4' to the first opening 5, and allow air to push the movable element 3' from the first position to the second position, or from the second position to the first position.

[0143] Alternatively, the first end 39 may have a reduction in diameter between the extension 48 adjacent the central portion 57 and the extension 49 (the first extension 43 adjacent the second portion 38 of the movable element 3').

[0144] Advantageously, during the step of cooling the preform, air is blown through the pin 1 ( Figure 5a ), the movable element 3′ is in the first position ( Figure 4c and Figure 5a ) or advanced position, and the air passage section through the hole 4' is at its maximum, not blocked or minimally blocked by the extension of the movable element 3', which has a diameter that facilitates sliding on the inner surface of the first tubular portion 2'. This allows effective cooling of the preform. Preferably, the extension of the movable element 3' (which can minimally block the passage section) is the first end 39 of the first part 37 of the movable element 3' or an extension 48 of the first end 39.

[0145] When the preform is held by sucking air through the pin 1 ( Figure 5b ) and the configuration of the ventilation circuit 50 is changed, the air suction from the hole 4' toward the first opening 5 of the body 2 pushes the movable element 3' to the second position ( Figure 5b) or retracted position and the air passage section through the hole 4 ′ is minimal, being largely blocked by the extension of the movable element 3 ′. Preferably, such an extension is the first end 39 of the first portion 37 or the extension 48, the diameter of which facilitates sliding on the inner surface of the first tubular portion 2 ′. This allows a greater vacuum to be generated, making it possible to effectively extract the preforms from the corresponding cooling shell 13 of the extraction plate 500 and to hold them on the processing station 20.

[0146] By changing the configuration of the ventilation circuit 50 again, the air blowing from the first opening 5 of the body 2 toward the hole 4' pushes the movable element 3' to the first position ( Figure 5a ).

[0147] like Figures 6a to 7b As shown, a third embodiment of the cooling and retaining pin according to the present invention provides for obtaining a single hole or at least two holes 4" on the second end of the body 2 (i.e. the tip of the pin). In particular, a single hole or at least two holes 4" are obtained in the side surface of the second end of the body 2.

[0148] In the example shown, four holes 4" are provided, each hole 4" preferably defining an axis inclined at an angle other than zero with respect to the longitudinal axis of the body 2. The number of holes 4" may be less than or even greater than four.

[0149] In particular, the body 2 of the pin comprises a first tubular portion 2 ′ or main portion comprising a first opening 5 connected to a first end of the body 2 of the processing station 20 .

[0150] The second end of the body 2 , opposite to the first end, comprises a second tubular portion 6 ″ in the form of a sleeve fastened to said first tubular portion 2 ′. A hole 4 ″ is obtained on the second tubular portion 6 ″ along a circumference coaxial with the longitudinal axis of the body 2 .

[0151] The movable element 3" is arranged at the second end of the body 2, passes through the second tubular portion 6", and can also partially slide inside the first tubular portion 2'.

[0152] Optionally, a sliding bushing 121 is provided inside the second tubular portion or sleeve 6″, which is located at a longitudinally outermost position than the hole 4″, preferably at the end of the sleeve 6″ away from the first opening 5. The movable element 3″ can slide in the sliding bushing 121.

[0153] The movable element 3" is preferably substantially cylindrical and at least partially hollow.

[0154] Advantageously, the hollow portion of the movable element 3″ is provided with first holes 8 in its first extension section 7, the number of which is equal to the number of holes 4″, the first holes 8 having a first size (e.g., a first diameter), and the hollow portion of the movable element 3″ is provided with second holes 10 in its second extension section 9, the number of which is equal to the number of holes 4″, the second holes 10 having a second size (e.g., a second diameter) smaller than the first size. Both the first holes 8 and the second holes 10 are arranged along respective circumferences coaxial with the longitudinal axis of the body 2. Preferably, the diameter of the first holes 8 is equal to or greater than the diameter of the holes 4″, while the diameter of the second holes 10 is smaller than the diameter of the holes 4″. Optionally, the diameter of the first holes 8 may be smaller than the diameter of the holes 4″ but larger than the diameter of the second holes 10.

[0155] The first end 51 of the movable element 3" is provided with an external radial shoulder or protrusion defining a first end-of-stroke element 11 which abuts against an internal shoulder 53 of the body 2, for example an internal shoulder 53 of the first tubular portion 2' or of the second tubular portion 6", when the movable element 3" is in the first position or blowing position.

[0156] The second end 52 of the movable element 3″ is part of the solid (non-hollow) part of the movable element 3″, and the second end 52 is provided with a shoulder, which defines a second stroke end element 11′, which abuts against the second end of the main body 2, i.e., the second tubular part 6″, when the movable element 3″ is in the second position or the suction position.

[0157] The movable element 3" is dimensioned so that in the first position ( Figure 7a ) only the first hole 8 is located at the corresponding hole 4", while in the second position ( Figure 7b ) Only the second hole 10 is located at the corresponding hole 4".

[0158] Therefore, it is advantageous to cool the preform by blowing air through the pin 1 ( Figure 7a ), the movable element 3″ is in the first position ( Figure 7a ) or advanced position, and the air passage cross-section through the hole 4″ is maximum because the hole 4″ is connected to the first hole 8 of the movable element 3″. The air from the first opening 5 passes through the first tubular portion 2′, enters the movable element 3″ and passes through the first hole 8 and the hole 4″ to the interior of the preform. This allows effective cooling of the preform.

[0159] When the preform is held by sucking air through the pin 1 ( Figure 7b ) and the configuration of the ventilation circuit 50 is changed, the air suction from the hole 4 ″ toward the first opening 5 of the body 2 pushes the movable element 3 ″ to the second position ( Figure 7b) or retracted position, and the air passage section through the hole 4″ is minimal, because the hole 4″ is connected to a second hole 10 of the movable element 3″ which is smaller than the first hole 8. This allows a greater vacuum to be generated, thereby effectively extracting the preform from the corresponding cooling shell 13 of the extraction plate 500 and holding it on the processing station 20.

[0160] By changing the configuration of the ventilation circuit 50 again, the air blown from the first opening 5 of the body 2 to the hole 4" pushes the movable element 3" to the first position ( Figure 7a ).

[0161] The movable element 3" is solid (not hollow) at its second end 52 so that the air cannot be discharged longitudinally along the second end of the body 2 during the blowing step, but is deflected laterally towards the aperture 4".

[0162] The first end 51 of the movable element 3" has a closed bottom along a plane transverse to (preferably orthogonal to) the longitudinal axis of the main body 2, and has at least one hole on the side surface, for example at least two holes 54, which are arranged along a circle coaxial with the longitudinal axis of the main body 2. Therefore, the inhaled air pushes the closed bottom of the first end 51 toward the first opening 5, moves the movable element 3" to the second position, and the air will enter the first tubular part 2' through the hole 54; while the blown air will push the closed bottom toward the hole 4", move the movable element 3" to the first position, and the air will enter the movable element 3" through the hole 54.

[0163] Many other shapes can be designed for the first end 51 of the movable element 3″, as long as they allow air to flow from the first opening 5 to the hole 4″, or allow air to flow from the hole 4″ to the first opening 5, and allow air to push the movable element 3″ from the first position to the second position, or from the second position to the first position.

[0164] In case of a single hole 4" in the second tubular portion 6", a corresponding single first hole 8 is provided in the extension 7 and a corresponding single second hole 10 is provided in the extension 9 of the movable element 3".

[0165] like Figures 8a to 10b As shown, a fourth embodiment of the cooling and retaining pin according to the invention provides for obtaining a single hole or at least two holes 40 along a circumference coaxial with the longitudinal axis of the body 2 on the first end of the body 2, i.e. the head portion of the pin 1. In particular, a single hole or at least two holes 40 are obtained in the side surface of the first end of the body 2.

[0166] In the example shown, four holes 40 are provided, each hole 40 defining an axis inclined at an angle other than zero with respect to the longitudinal axis of the body 2. The number of holes 40 may be less than or even greater than four.

[0167] The body 2 of the pin comprises a first end 61 comprising the first opening 5 of the body 2 and adapted to be connected to the processing station 20. In particular, the first end 61 is adapted to be arranged in a housing of the processing station 20.

[0168] The second end 62 of the body 2 is adapted to be arranged outside the housing. In the second end 62, at least one further single hole or at least two further holes 40' are provided, in this example four further holes 40' are provided, arranged along a circumference coaxial with the longitudinal axis; each further hole 40' defines an axis inclined at an angle other than zero with respect to the longitudinal axis of the body 2. The second end 62 has a closed bottom transverse to the longitudinal axis, and the holes 40' are arranged in the vicinity of the closed bottom, preferably in the chamfered area provided between the closed bottom and the cylindrical extension of the second end 62.

[0169] The actuating means are arranged in the inner volume of the housing and are adapted to move the movable element 30 closing the first opening 5 from the first position or the retracted position ( Fig.10a ) is actuated to the second or forward position ( Fig.10b ), the first position or retracted position corresponds to a first air passage section of each hole 40, for blowing air from the hole 40 to the second end 62 of the main body 2, and the second position or advanced position corresponds to a second air passage section of each hole 40, for sucking air from the second end 62 and therefore from the hole 40′ toward the hole 40.

[0170] In an advantageous variant of the processing station 20 ( Figure 9b ), a pneumatic circuit is provided, which comprises inside the housing at least one first distribution manifold 63, for example a single first distribution manifold 63, which delivers compressed air from a suitable source (not shown) and distributes it on a plurality of second distribution manifolds 64, which are transverse to, for example orthogonal to, the first distribution manifold 63. Each second distribution manifold 64 can in turn actuate a plurality of actuators by compressed air, each actuator being suitable for moving the movable element 30 of a corresponding pin from a first position ( Fig.10a ) to the second position ( Fig.10b ). For example, each second distribution manifold 64 corresponds to a row of preform cooling and holding pins of a processing station 20.

[0171] In this embodiment, purely by way of explanation, the movable element 30 comprises a cap 65 fastened to a piston rod of a micro-cylinder 66 representing the associated actuating means. For example, a column of micro-cylinders 66 is connected to a respective second distribution manifold 64.

[0172] Advantageously, during the step of cooling the preform, air is blown through the pin 1 ( Fig.10a), the compressed air does not circulate in the second distribution manifold 64, and the movable element 30 is in the first position ( Fig.10a ) or retracted position, and the air passage section through the hole 40 is maximum, not blocked or minimally blocked by the movable element 30. The air supplied by the ventilation circuit 50 in the housing passes through the hole 40, the tubular body 2, and out of the hole 40' to the interior of the preform. This allows effective cooling of the preform.

[0173] When the step of holding the preform by sucking air through the pin 1 ( Fig.10b ) When the configuration of the ventilation circuit 50 is changed, the compressed air circulates in the second distribution manifold 64 and pushes / maintains the movable element 30 to the second position ( Fig.10b ) or advanced position, and the air passage section through the hole 40 is minimal, being largely blocked by the movable element 30. The air sucked from the interior of the preform passes through the hole 40', the tubular body 2, and out of the hole 40 with a reduced section to the interior of the housing. This allows a greater vacuum to be generated, making it possible to effectively extract the preform from the corresponding cooling shell 13 of the extraction plate 500 and hold it on the processing station 20.

[0174] By changing the configuration of the ventilation circuit 50 again, the compressed air no longer circulates in the second distribution manifold 64 and the movable element 30 returns to the first position ( Fig.10a ).

[0175] Figures 11a to 13b The fifth embodiment of the cooling and holding pin according to the invention shown differs from the fourth embodiment described above in that the movable element and its actuation means belong to the processing station 20 .

[0176] The movable element 30 may be a cap closing the first opening 5 of the first end 61 of the body 2 , the cap being moved by a moving structure actuated by a pneumatic actuator.

[0177] In an advantageous variant of the processing station 20, a structure for moving the caps 30 is provided, which structure includes a plurality of cap supports 71, each support 71 supporting a series of caps, for example a row or half row of caps (corresponding to a row or half row of pins 1 in a matrix arranged in the processing station 20).

[0178] The plurality of supports 71 are moved by at least one mobile bracket 72 , which moves transversely to the supports 71 and which in turn is moved by at least one pneumatic actuator 73 .

[0179] exist Figure 12b In the example of , the plate 67 of the processing station to which the pins 1 are fixed is divided into four equal areas, two upper areas and two lower areas.

[0180] In each area, a moving bracket 72 is provided to move a corresponding plurality of support members 71, each of which supports a half-column cap.

[0181] Between each upper zone and the underlying lower zone of the plate 67 , there is provided a fastening bracket 74 fastened to the plate 67 , which supports at least two pneumatic actuators 73 , each of which is suitable for moving a respective mobile bracket 72 .

[0182] In each region, at least one connecting crosspiece 75 may optionally be provided to help hold the supports 71 integral with each other during movement.

[0183] Advantageously, during the step of cooling the preform, air is blown through the pin 1 ( Fig.13a ), the movable element 30 (eg in the form of a cap) is in a first position ( Fig.13a ) or retracted position, and the air passage section for air passing through the hole 40 is maximum, not blocked or minimally blocked by the movable element 30. The air supplied by the ventilation circuit 50 in the housing passes through the hole 40, the tubular body 2, and comes out of the hole 40' to the interior of the preform. This allows effective cooling of the preform.

[0184] When the step of holding the preform by sucking air through the pin 1 ( Fig.13b ) to change the configuration of the ventilation circuit 50, the pneumatic actuator 73 moves the movable bracket 72 in the first direction and thereby pushes the corresponding support 71, which pushes / holds the movable element 30 to / in the second position ( Fig.13b ), in the second position, the air passage section through the hole 40 is minimal, being largely blocked by the movable element 30. The air sucked from the interior of the preform passes through the hole 40', the tubular body 2 and out of the hole 40 of reduced section to the interior of the housing. This allows a greater vacuum to be created, making it possible to effectively extract the preform from the corresponding cooling shell 13 of the extraction plate 500 and hold it on the processing station 20.

[0185] By changing the configuration of the ventilation circuit 50 again, the pneumatic actuator 73 moves the movable bracket 72 in a second direction opposite to the first direction, and then retracts the corresponding support 71, which retracts and holds the movable element 30 in the first position ( Fig.13a ).

[0186] exist Fig.14 , Fig.15a and Fig.15bIn the sixth embodiment shown, only one gap 400 is provided at the second end of the body 2, i.e. in the region of the tip of the pin. The movable element 300 can slide inside the body 2 at said second end along the longitudinal axis of the body 2. A single gap 400, annular and coaxial with said longitudinal axis, is located between the inner surface of the body 2 and the outer surface of the movable element 300.

[0187] In particular, the body 2 of the pin comprises a first tubular portion 700 comprising a first opening 5 at a first end of the body 2 and connected to the processing station 20. The second end of the body 2, opposite to the first end, is provided with a second tubular portion 600 in the form of a sleeve defining an end-of-travel element which delimits therein the travel of the movable element 300 from the second position or suction position to the first position or blowing position. The second tubular portion or sleeve 600 is fastened to the end of the first tubular portion 700 remote from the first opening 5.

[0188] exist Fig.14 , Fig.15a and Fig.15b In the example shown, the movable element 300 comprises:

[0189] a first portion 12 or first end, which is remote from the first tubular portion 700 and therefore remote from the first opening 5;

[0190] and a second portion 15 , which is close to the first opening 5 and adjacent to the first portion 12 .

[0191] The second portion 15 has smaller dimensions than the first portion 12 . In particular, the second portion 15 has a radial extension perpendicular to the longitudinal axis of the body 2 that is smaller than the radial extension of the second portion 12 .

[0192] Advantageously, the movable element 300 is adapted to move along the longitudinal axis of the body 2 so that when the position of the first portion 12 relative to the body 2 varies, the size of the gap 400 varies, or more generally the size of the air passage section varies.

[0193] Preferably, in the blowing position ( Fig.14 and Fig.15a ), the gap 400 is between the inner surface of the end opening 5' of the second tubular portion 600 of the body 2 and the outer surface of the second portion 15 of the movable element 300; and in the suction position ( Fig.15b ), a gap 400 is between the inner surface of the end opening 5′ of the second tubular portion 600 and the outer surface of the first portion 12 of the movable element 300.

[0194] End-of-travel elements are provided to limit the travel of the movable element 300 in both directions.

[0195] For example, the movable element 300 comprises a third portion 16 or second end adjacent to the first tubular portion 700, and therefore adjacent to the first opening 5, and adjacent to the second portion 15 of the movable element. Thus, the second portion 15 is an intermediate portion between the first portion 12 and the third portion 16.

[0196] The third portion 16 at least partially has a larger dimension than the second portion 15, in particular a larger radial dimension, so as to define:

[0197] a first abutment surface adapted to abut against an inner shoulder 17 of the second tubular portion 600 when the element is moved into the blowing position;

[0198] and a second abutment surface opposite said first abutment surface, suitable for abutting against an end of the first tubular portion 700 or against another internal shoulder of the second tubular portion 600 close to the first tubular portion 700 when the movable element is moved into the suction position.

[0199] For example, the third portion 16 is provided with at least one protrusion adapted to slide on the inner surface of the sleeve 600 and abut against the first tubular portion 700 of the body 2 in the retracted or suction position. Preferably, the third portion 16 is provided with three radial protrusions, preferably arranged at 120° to each other.

[0200] Preferably, the movable element 300 is mushroom-shaped, which is the typical shape of an exhaust valve or a suction valve placed in a four-stroke engine head.

[0201] During the process of blowing air from the first opening 5 toward the second end of the main body 2, the movable element 300 is in the first position ( Fig.14 and Fig.15a ) or advanced position, the gap 400 has its maximum size, allowing effective cooling of the preform. In this advanced position, the movable element 300 abuts against the inner shoulder 17 of the sleeve 600.

[0202] When changing the configuration of the ventilation circuit 50, the air suction from the gap 400 toward the first opening 5 of the body 2 pushes the movable element 300 to the second position ( Fig.15b ) or retracted position, the gap 400 has its smallest size, allowing a greater vacuum to be generated, thus effectively extracting the preform from the corresponding cooling shell 13 of the extraction plate 500 and retaining it on the processing station 20. In this retracted position, the movable element 300 abuts against the first tubular portion 700 of the body 2.

[0203] Preferably, the movable element 300 has a longitudinal extension along the axis X so as to cover, in said retracted position, the distance ( Fig.15b ).

[0204] By changing the configuration of the ventilation circuit 50 again, the air blowing from the first opening 5 to the second opening 5' of the main body 2 pushes the movable element 300 to the first position ( Fig.14 and Fig.15a ).

[0205] exist Figures 16 to 22 In the seventh embodiment shown, the body 2 has a second opening 5 ′ coaxial with the longitudinal axis X at said second end.

[0206] In particular, the body 2 of the pin comprises a first tubular portion 701 comprising a first opening 5 at a first end of the body 2 and connected to the processing station 20. A second end of the body 2, opposite to the first end, is provided with a second tubular portion 601 in the form of a sleeve defining an end-of-stroke element in which the movable element 301 is delimited from the second position or suction position ( Fig.18b ) to the first position or blowing position ( Fig.18a The second tubular portion or sleeve 601 is fastened to the end of the first tubular portion 701 away from the first opening 5. The sleeve 601 is integral with the first tubular portion 701 and is coaxial.

[0207] Advantageously, the movable element 301 is provided with an internal duct 302 along the longitudinal axis X and preferably coaxial with the axis X and adapted to:

[0208] - sliding from a first position or blowing position in which at least one gap comprises at least a part of the internal duct 302 and the second opening 5 ′ for the passage of the blowing air flow,

[0209] - Sliding to a second position or suction position, in which at least one gap is defined only by the internal duct 302 for the passage of the suction airflow.

[0210] Preferably, the movable element 301 has a central portion 303 provided with at least one protrusion 304 adapted to slide on the inner surface of the sleeve 601 and abut at the second opening 5 ′, for example against the inner shoulder 17 of the second tubular portion 601 , in the blowing position.

[0211] exist Figure 19-22In the variant shown, the central portion 303 is provided with three radial protrusions 304, which are preferably arranged at 120° to each other. Fig. 20 ), at least one gap includes an internal duct 302 and three parts 310 of a second opening 5' for passing a blowing airflow.

[0212] As shown, the three radial protrusions 304 are preferably convex angled, with a curved contact surface 307 (corresponding to the inner surface 602 of the sleeve 601) Fig. 20 ).

[0213] Preferably, the movable element 301 has a first end 305 which in the blowing position at least partially protrudes from the second opening 5' and has a second end 306 opposite the first end 305 which in the suction position is at least partially inserted into the internal duct 200 of the first tubular part 701.

[0214] The central portion 303 is a middle portion between the first end portion 305 and the second end portion 306 .

[0215] During the process of blowing air from the first opening 5 toward the second end of the main body 2, the movable element 301 is in the first position ( Fig.18a ) or advanced position, the blowing gap has its maximum size, allowing effective cooling of the preform. In this advanced position, the movable element 301 abuts against the inner shoulder 17 of the sleeve 601.

[0216] When changing the configuration of the ventilation circuit 50, the air suction from the second opening 5' towards the first opening 5 of the body 2 pushes the movable element 301 to the second position ( Fig.18b ) or retracted position, the gap has its smallest dimensions, allowing a greater vacuum to be generated, thus effectively extracting the preform from the corresponding cooling shell 13 of the extraction plate 500 and retaining it on the processing station 20. In this retracted position, the movable element 301 is partially inserted with its second end 306 in the first tubular portion 701 of the body 2.

[0217] By changing the configuration of the ventilation circuit 50 again, the air blowing from the first opening 5 to the second opening 5' of the main body 2 pushes the movable element 301 to the first position ( Fig.18a ).

Claims

1. A cooling and holding pin (1) for cooling a preform of plastic material by air blowing and for holding the preform of plastic material by air suction, the cooling and holding pin comprising: a body (2) defining a longitudinal axis and having a first opening (5) at a first end of the body, the first opening being coaxial with the longitudinal axis and adapted to be connected to a processing station; a movable element (3, 3', 3", 30, 300, 301) adapted to slide at least partially inside the body (2); at least one gap for passage of air during the blowing step and the sucking step, the at least one gap being arranged at a second end of the body (2) or at the first end, the second end being opposite to the first end; The movable element (3, 3', 3", 30, 300, 301) is suitable for moving from a first position corresponding to a first cross-section of a passage for air passing through the at least one gap to a second position corresponding to a second cross-section of a passage for air passing through the at least one gap, the second cross-section being smaller than the first cross-section, thereby adjusting the blowing airflow in the first position during the cooling step and adjusting the suction airflow in the second position during the step of holding the preform.

2. The cooling and retaining pin according to claim 1, wherein: The body (2) has a second opening (5') at the second end, the second opening being coaxial with the longitudinal axis, The movable element (301) is provided with an inner conduit (302) along the longitudinal axis and is suitable for sliding from said first position to said second position, in which said at least one gap comprises at least a portion of said inner duct (302) and said second opening (5') for said blowing air flow, In the second position, the at least one gap is defined only by the inner duct (302) for the suction airflow.

3. The cooling and retaining pin according to claim 2, wherein: The second end of the body (2) is provided with a sleeve (601), which is integral and coaxial with the body (2) and is suitable for defining a travel of the movable element (301) from the second position to the first position.

4. The cooling and retaining pin according to claim 3, wherein: The movable element (301) has a central portion (303) provided with at least one protrusion (304) adapted to slide on the inner surface of the sleeve (601) and to abut at the second opening (5') in the first position.

5. The cooling and retaining pin according to claim 4, wherein: The central portion (303) is provided with three radial protrusions (304).

6. The cooling and retaining pin according to claim 5, wherein: The three radial protrusions are arranged at 120° to each other.

7. A cooling and retaining pin according to any one of claims 4 to 6, wherein: The movable element (301) has a first end (305), which at least partially protrudes from the second opening (5') in the first position, and the movable element (301) has a second end (306) opposite to the first end (305), which at least partially inserts into the internal pipe (200) of the body (2) in the second position.

8. The cooling and retaining pin according to claim 1, wherein: The movable element (300) comprises a first portion (12) and a second portion (15) along the longitudinal axis, the first portion (12) being remote from the first opening (5), the second portion (15) being adjacent to the first portion (12) and close to the first opening (5), the first portion (12) having a larger size relative to the second portion (15); Only one gap (400) is provided at the second end of the body (2), the gap being comprised between the inner surface of the body (2) and the outer surface of the movable element (300); The movable element (300) is adapted to move such that the size of the gap (400) changes when the position of the first portion (12) relative to the body (2) changes.

9. The cooling and retaining pin according to claim 8, wherein: In the first position, the gap (400) is included between the inner surface of the body (2) and the outer surface of the second part (15), and in the second position, the gap (400) is included between the inner surface of the body (2) and the outer surface of the first part (12).

10. The cooling and retaining pin according to claim 1, wherein: The at least one gap is at least one hole arranged along a circumference coaxial with the longitudinal axis.

11. The cooling and retaining pin according to claim 10, wherein: A single hole or at least two holes (4, 4', 4", 40) are provided, the holes being arranged along a circumference coaxial with the longitudinal axis, and wherein the movable element (3, 3', 3", 30) is adapted to move from a first position corresponding to the first cross-section for the passage of air through the single hole or each hole to a second position corresponding to the second cross-section for the passage of air through the single hole or each hole.

12. The cooling and retaining pin according to claim 11, wherein: In case the single hole or the at least two holes (4) are located at the second end of the body (2), the single hole or the at least two holes (4) are provided in the movable element (3) arranged at the second end, The movable element (3) is in the first position or the advanced position, and in the process of blowing air from the first opening (5) toward the second end of the main body (2), the single hole or the at least two holes (4) are mainly placed outside the main body (2); when the movable element (3) is in the second position or the retracted position, in the process of sucking air from the single hole or the at least two holes (4) toward the first opening (5) of the main body (2), the single hole or the at least two holes (4) are mainly placed inside the main body (2).

13. The cooling and retaining pin according to claim 12, wherein: The second end of the body (2) is provided with a sleeve (6), which is integral and coaxial with the body (2) and is suitable for defining the travel of the movable element (3) from the second position to the first position therein.

14. The cooling and retaining pin according to claim 11, wherein: in the case where the single hole or the at least two holes (4') are located at the second end of the body (2), the single hole or the at least two holes (4') are provided on the second end of the body (2) and the movable element (3') is arranged at the second end, And wherein, when the movable element (3′) is in the first position or the advanced position, in the process of blowing air from the first opening (5) toward the second end of the main body (2), the single hole or the at least two holes (4′) have the first cross-section for the passage of air; and when the movable element (3′) is in the second position or the retracted position, in the process of sucking air from the single hole or from the at least two holes (4′) toward the first opening (5) of the main body (2), the single hole or the at least two holes (4′) have the second cross-section for the passage of air, and the second cross-section is smaller than the first cross-section.

15. The cooling and retaining pin according to claim 14, wherein: A sleeve (6') is provided at the second end of the main body (2) at a position further outward relative to the single hole or the at least two holes (4'), the sleeve being integral with the main body (2) and coaxial with the main body, and being suitable for limiting the stroke of the movable element (3') from the first position to the second position and from the second position to the first position.

16. The cooling and retaining pin of claim 11, wherein: in the case where the single hole or the at least two holes (4") are located at the second end of the body (2), the single hole or the at least two holes (4") are provided on the second end of the body (2) and the movable element (3") is arranged at the second end, wherein the movable element (3″) is provided with only one first hole or at least two first holes (8) having a first size in its first extension (7), and is provided with only one second hole or at least two second holes (10) in its second extension (9), the second holes having a second size smaller than the first size, And wherein, when the movable element (3″) is in the first position or the advanced position, in the process of blowing air from the first opening (5) toward the second end of the main body (2), the only one first hole or the at least two first holes (8) are respectively connected with the single hole or the at least two holes (4″) of the main body (2); when the movable element (3″) is in the second position or the retracted position, in the process of sucking air from the single hole or from the at least two holes (4″) toward the first opening (5) of the main body (2), the only one second hole or the at least two second holes (10) are respectively connected with the single hole or the at least two holes (4″) of the main body (2); wherein a first end-of-stroke element (11) is integral with the movable element (3") and, when the movable element (3") is in the first position, the first end-of-stroke element (11) abuts against an inner shoulder of the body (2), And wherein the second end-of-stroke element (11') is integral with the movable element (3"), and when the movable element (3") is in the second position, the second end-of-stroke element (11') abuts against the second end of the body (2).

17. The cooling and retaining pin according to claim 16, wherein: A sliding bushing (121) is provided inside the second end of the main body (2), and the movable element (3") is able to slide in the sliding bushing.

18. The cooling and retaining pin of claim 11, wherein: In the case where the single hole or the at least two holes (40) are located at the first end, the single hole or the at least two holes (40) are arranged on the body (2), and wherein said movable element (30) closes said first opening (5) in said first end, The movable element (30) is adapted to be arranged in the first position or in a retracted position corresponding to the first cross section of the air passage for the single hole or the at least two holes (40) for blowing air from the single hole or from the at least two holes (40) towards the second end of the body (2), And the movable element (30) is suitable for being arranged in the second position or the advanced position, which corresponds to the second cross-section of the air channel for the single hole or the at least two holes (40), and is used to draw air from the second end of the body (2) toward the single hole or the at least two holes (40).

19. The cooling and retaining pin according to claim 18, wherein: In the second end of the body (2), at least one further hole (40') is provided, arranged along a circumference coaxial with the longitudinal axis.

20. The cooling and retaining pin of claim 19, wherein: At least two further holes (40') are provided, each further hole (40') defining an axis having an inclination angle other than zero relative to the longitudinal axis.

21. A processing station (20) for processing plastic preforms and adapted to cooperate with an extraction plate (500) adapted to extract the preforms from an injection mould, the processing station comprising a housing defining an inner volume, the inner volume communicating on one side with a plurality of cooling and holding pins (1) according to any one of claims 1 to 20 and adapted to communicate on the other side with a ventilation circuit (50), wherein the housing has at least one surface (14) on which the plurality of cooling and retaining pins (1) are arranged, wherein the first end of the body (2) of each cooling and retaining pin (1) having the first opening (5) is arranged within the housing, And among them, The second end of the body (2) of each cooling and retaining pin (1) is arranged outside the housing.

22. The processing station according to claim 21, wherein In the case where the at least one gap is a single hole (40) or comprises at least two holes (40) at the first end, the single hole (40) or the at least two holes (40) are arranged on the first end of the body (2) along a circumference coaxial with the longitudinal axis, and wherein an actuating device is provided in the inner volume, the actuating device being suitable for actuating the movable element (30) closing the first opening (5) to transition from the first position to the second position, the first position corresponding to a first cross section of the air passage for the single hole (40) or the at least two holes (40) for blowing air from the single hole (40) or from the at least two holes (40) towards the second end of the body (2), The second position corresponds to a second cross section of the air passage for the single hole (40) or the at least two holes (40) for drawing air from the second end of the body (2) towards the single hole (40) or the at least two holes (40).

23. An apparatus for treating and cooling plastic preforms, comprising: The processing station (20) according to claim 21; a ventilation circuit (50) connected to the treatment station (20); The ventilation circuit (50) comprises: a suction duct (60) for sucking air from the interior of the treatment station (20); a delivery pipe (70) for delivering air to the processing station (20); a cooling device (80) disposed along the conveying duct (70) for cooling the air delivered to the processing station (20); And wherein, a switching device of the ventilation circuit is also provided to change from a first circuit configuration to a second circuit configuration, in which an air passage from the conveying duct (70) to the processing station (20) is possible, and in the second circuit configuration, an air passage from the processing station (20) to the suction duct (60) is possible, so that in the first circuit configuration, air can be blown through the multiple cooling and retaining pins (1), and in the second circuit configuration, air can be sucked through the multiple cooling and retaining pins (1).

24. An injection molding machine, comprising a housing (21), wherein at least: at least one injection mold (22) comprising a plurality of mold cavities; at least one extraction plate (500) comprising at least one set of cooling shells (13) adapted to receive and hold at least one set of preforms extracted from the mold cavity; the cooling shells (13) adapted to remove a first amount of thermal energy from the preforms by conduction; and a device for processing and cooling plastic preforms according to claim 23; wherein the processing station (20) is configured to be transferred from a loading position for cooperating with the extraction plate (500) to an unloading position for releasing the preform from the cooling and holding pins (1), Wherein, in the loading position, the cooling and holding pins (1) of the processing station (20) are suitable for cooperating with the corresponding cooling shell (13) of the extraction plate (500) to remove a second amount of thermal energy from the preform during the step of blowing air through the cooling and holding pins (1) when the ventilation circuit is in the first circuit configuration, and then to hold the preform and extract the preform from the cooling shell (13) during the step of drawing air through the cooling and holding pins (1) when the ventilation circuit is in the second circuit configuration.

25. A method for processing and cooling plastic preforms in an injection molding machine according to claim 24, the method comprising the following steps: arranging the processing station (20) in the loading position, the processing station (20) being arranged facing the extraction plate (500) containing at least one group of preforms in the corresponding cooling housing (13), and arranging the ventilation circuit (50) in the first circuit configuration; inserting the cooling and holding pins (1) of the processing station (20) into the corresponding cooling housings (13) and further cooling the preforms contained in the cooling housings (13) by blowing air through the cooling and holding pins (1) with the movable elements (3, 3', 3", 30, 300, 301) in the first position; Switching the ventilation circuit (50) from the first circuit configuration to the second circuit configuration by means of the switching device and drawing air through the cooling and holding pins (1) so that the movable element (3, 3', 3", 30, 300, 301) is in the second position to hold the preform on the processing station (20); disengaging the cooling and retaining pins (1) from the respective cooling housings (13), continuing to draw air through the cooling and retaining pins (1), wherein the movable element (3, 3', 3", 30, 300, 301) is in the second position; moving the processing station (20) from the loading position to the unloading position, continuing to draw air through the cooling and holding pins (1), wherein the movable element (3, 3', 3", 30, 300, 301) is in the second position; The ventilation circuit (50) is switched from the second circuit configuration to the first circuit configuration by the switching device, and air is blown through the cooling and holding pins (1) to release the preforms from the cooling and holding pins.

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