Male element of the mold

Abstract

The male element (100) of the mold (10) for compression-molding the parison comprises a die (110) extending along a longitudinal axis (A), the die (110 including a body (112) having a longitudinal cavity (113) extending along the longitudinal axis (A) therein and a socket (111) at one end thereof communicating with the longitudinal cavity (113), and a stretch rod (120) slidably inserted into the longitudinal cavity (113), the stretch rod (120) including an end portion (121) at one end thereof, the stretch rod (120) being movable relative to the die (110) between a retracted position in which the end portion (121) is housed in the socket (111) and an extended position in which the end portion (121) is extended from the socket (111).

Description

[Technical Field]

[0001] The present invention relates to a male element of a mold, a mold, a forming and blow molding machine and a method for compression molding and blow molding a parison. [Background technology]

[0002] The prior art is known to provide machines for forming a parison by molding and then blow-molding the parison to obtain a container. More specifically, patent documents WO 2008 / 110887 A2 and WO 2007107822 A2 in the name of the present applicant disclose machines for forming a parison by compression molding and then blow-molding the parison. The machine comprises a number of molds, each of which comprises a male element and a female element configured to form the parison by compression molding. After molding, the female element is separated from the male element, while the parison remains attached to the male element. The parison is then stretched by a stretch rod that can be extracted from the female element, and is then blown into a blow-molding cavity to obtain a container.

[0003] Patent document US10781010B2 also discloses a machine configured to form a parison by compression molding and then blow molding it.Patent document US8790112B2 discloses a machine configured to form a parison by injection molding and then blow molding it.

[0004] Prior art forming and blow molding machines have several drawbacks. First, the parison is very hot immediately after forming and must be cooled before blow molding. Cooling must be as uniform as possible to ensure high quality of the container and fast to reduce cycle time. This need for cooling is especially felt when forming is done by compression.

[0005] Also, in prior art molds, the air for blowing is blown through channels formed in the stretch rod, a solution that requires the stretch rod to be relatively thick and generally results in a complex design.

[0006] Additionally, after molding, when the female mold half is separated from the male mold half, in some cases the parison may not remain properly attached to the male mold half, resulting in surface imperfections on the parison and therefore the container.

[0007] Additionally, there may be problems caused by breakage of the stretch rod during extension and / or retraction of the stretch rod.

[0008] Other examples of machines configured to form a parison by compression molding and then blow mold it are provided by patent documents CH431030A, US2012100241A1, US4150689A and US4473515A, however, these documents do not disclose solutions that can meet market requirements. Summary of the Invention

[0009] It is an object of the present disclosure to provide a male element of a mold, a mold, a forming and blow molding machine, and a method for compression molding and blow molding of a parison to overcome the above-mentioned shortcomings of the prior art.

[0010] This object is fully achieved by the male element, mold, machine and method of the present disclosure as characterized in the appended claims.

[0011] The present disclosure relates to a male element of a mold. The mold is configured to form a parison. Preferably, the mold is configured to compression mold the parison from a pre-prepared dose of thermoplastic material. However, the disclosure is also applicable to male elements of injection molding or injection-compression molding.

[0012] The male element can be associated with the female element of the mold to define a forming cavity in which the parison is formed. For example, the male element can define an upper mold half and the female element can define a lower mold half (or the male element can define the lower mold half and the female element can define the upper mold half), and the male and female elements can move toward and away from each other between an open position in which they receive a dose of thermoplastic material and a closed position in which they define a forming cavity for molding the dose of material to form the parison. Preferably, the dose is received by the lower mold half. For example, the dose can be extruded onto the lower mold half by a dose extruder.

[0013] The male element comprises a die. The die extends along a longitudinal axis. The die includes a body having a longitudinal cavity therein extending along the longitudinal axis. One end of the body (i.e., die) is provided with a socket in communication with the longitudinal cavity. By socket is meant a recessed or concave zone formed in the outer surface of the die.

[0014] The male element comprises a stretch rod. The stretch rod is slidably inserted into the longitudinal cavity. The stretch rod includes an end portion at one end. The stretch rod also comprises an elongate body extending along the longitudinal axis and connected to the end portion. Preferably, the longitudinal cross section of the end portion is larger than the longitudinal cross section of the elongate body of the stretch rod. The stretch rod is movable (slidable) relative to the die between a retracted position and an extracted position. In the retracted position, the end portion is housed in the socket and thus, together with the die, contributes to defining the forming cavity. In the retracted position, the elongate body of the stretch rod is housed within the longitudinal cavity. In the extracted position, the end portion is extracted from the socket to stretch the parison. In the extracted position, the elongate body of the stretch rod is partially housed inside and partially outside the longitudinal cavity.

[0015] The male element provides a passage for air flow for blowing the parison to form the container.

[0016] It should be noted that during stretching and blow molding, the male element is associated with a blow molding cavity that is used in place of the female element, the blow molding cavity having the shape of the container to be formed.

[0017] Preferably, the die includes a cooling circuit therein configured to allow the flow of a cooling fluid, which may be, for example, water.

[0018] In one example, the air flow passage is defined by a portion of the longitudinal cavity. In one example, the air flow passage is defined by a portion of the longitudinal cavity between the outer surface of the stretch rod and the inner surface of the body that defines the longitudinal cavity. As a possible alternative, the air flow passage may be defined within the interior of the stretch rod.

[0019] The air flow passage may include a gap formed by a portion of the longitudinal cavity. Preferably, the air flow passage includes a gap formed by a portion of the longitudinal cavity between the outer surface of the stretch rod and the inner surface of the die that defines the longitudinal cavity.

[0020] In one example, the air flow passage comprises a gap formed by a portion of the longitudinal cavity between the outer surface of the stretch rod and the inner surface of the body that defines the longitudinal cavity.

[0021] In practice, the stretch rod is at least partially spaced from the inner wall of the die body that defines the longitudinal cavity, thereby defining a gap between the stretch rod and the inner wall of the die body that is configured to allow airflow therethrough. The gap extends along the longitudinal axis. Note that the gap extends to a socket, which has an outlet therein that allows the airflow to escape. Preferably, in the retracted position, the end portion of the stretch rod blocks the outlet to prevent air from flowing from the gap into the forming cavity. Meanwhile, in the extended position, the end portion is away from the socket, so that the outlet is open, allowing air to flow through the gap.

[0022] Preferably, the gap has a (at least partly) tubular shape and surrounds the stretch rod, and the outlet is annular in shape.

[0023] Preferably, the male element comprises an actuation unit configured to drive the movement of the stretch rod from the extended position to the retracted position and from the retracted position to the extended position. In one embodiment, the male element also comprises a damping device configured to slow down the movement of the stretch rod from the extended position to the retracted position. The damping device is associated with the actuation unit. More specifically, the damping device is configured to slow down the stretch rod at the end of its movement from the extended position to the retracted position. Indeed, if the stretch rod reaches the end of its stroke too quickly, the impact will damage the stretch rod.

[0024] In one embodiment, the male element comprises a diffuser rod extending between a first end connected to the extension rod and a second end opposite the first end. In one embodiment, the first end of the diffuser rod is connected to the extension rod by a threaded connection. More specifically, the first end of the diffuser rod defines a threaded cavity into which the threaded end of the extension rod is threaded. The actuation unit is connected to the second end of the diffuser rod and configured to move the diffuser rod between a first position corresponding to the extended position of the extension rod and a second position corresponding to the retracted position of the extension rod. In this manner, the actuation unit moves the diffuser rod, and the diffuser rod moves the extension rod. Preferably, a damping device is attached to the second end of the diffuser rod (i.e., in the connection zone between the diffuser rod and the actuation unit) and configured to slow the movement of the diffuser rod from the first position to the second position. The damping device is preferably configured to decelerate the diffuser rod at the end of its movement from the first position to the second position. This avoids failure of the extension rod and / or the threaded connection between the extension rod and the diffuser rod.More specifically, the damping device may include a spring attached to the second end of the diffuser rod.

[0025] It should be noted that in one embodiment, the male element does not need to include a stretch rod or a longitudinal cavity into which the stretch rod slides. In fact, in this embodiment, the die is retractable relative to the upper part of the male element so that it can move together with the upper part between a retracted position, in which it contributes to defining the forming cavity, and an extended position, which is configured to stretch the parison in the same way as described in patent document US10781010B2. In this embodiment, air passages are formed inside the die. Cooling circuits are also formed inside the die.

[0026] The cooling circuit includes at least one delivery duct for circulating cooling fluid toward the end of the die and at least one return duct for circulating cooling fluid back from the end of the die, the return duct being connected in series with the delivery duct.

[0027] In one embodiment, the delivery duct and / or the return duct are coil-shaped, i.e., configured to guide the cooling fluid through multiple passages or coils. More specifically, the delivery duct and / or the return duct may be helically shaped. In one embodiment, the delivery duct and / or the return duct may be helically shaped such that each has a double helix. In one embodiment, the delivery duct has a first helix wound around the longitudinal axis, and the return duct has a second helix wound around the longitudinal axis. More specifically, at least one turn of the first helix is ​​disposed along the longitudinal axis between a first turn and a second turn of the second helix.

[0028] In one example, the airflow passage is separate from the cooling circuit. Preferably, the airflow passage and the cooling circuit define separate conduits.

[0029] In one example, the body has an outer surface opposite the inner surface, i.e., the surface at least partially defining the longitudinal cavity. Preferably, the cooling circuit is in at least contact with the outer surface of the body.

[0030] In effect, the cooling circuits and the airflow passages define separate conduits, since the airflow passages (or gaps) are in contact with the interior surface of the body while the cooling circuits are in contact with the exterior surface of the body.

[0031] In one embodiment, the die includes a liner mounted around the body, the cooling circuit being formed between the body and the liner. More specifically, the outer surface of the body facing the liner is grooved to form a concave surface that acts with a corresponding portion of the inner surface of the liner to define a duct for the cooling fluid. Preferably, the outer surface of the body also has a contact or support zone in contact with the liner.

[0032] The structure defined by the grooved body and the liner mounted and supported about the body allows the liner to be made relatively thin, and therefore has low thermal resistance, thereby improving cooling efficiency.

[0033] Preferably, the male element comprises an abutment element configured to abut against the annular periphery of the female element, a support element, and an elastic element connected between the abutment element and the support element. The support element is connected to the die. Preferably, the die is movable relative to the support element. The abutment element is movable relative to the support element between a rest position, in which the elastic element keeps the abutment element spaced apart from the support element, and a working position, in which the abutment element contacts the support element. The abutment element can be positioned in the working position by the effect of pressure exerted on the abutment element by the female element. More specifically, when the mold is in a closed configuration in which the male and female elements approach each other to define the forming cavity, the female element applies pressure to the abutment element. In the working position, the elastic element is compressed, and the abutment element approaches the support element. The elastic element ensures good contact between the female element and the male element, even in the presence of slight inaccuracies in the actuation unit that closes the mold.

[0034] Preferably, the mould also comprises a locking device configured to engage with the abutment element to keep it in the working position even when the female element no longer exerts pressure on it: in fact, in the absence of pressure exerted by the female element and in the absence of the locking device, the abutment element, under the action of the elastic element, tends to settle into a rest position away from the support element.

[0035] The locking device can be positioned in a locking position to lock the abutment element in the working position. The locking device can also be positioned in a resting position where it does not interfere with the abutment element, allowing the abutment element to be positioned in the resting position away from the support element. While the mold is being closed, the locking device is in the resting position, and the abutment element moves to the working position due to the pressure exerted on the abutment element by the female element. When the mold is closed, the locking device is activated and positioned in the working position to engage the abutment element. Then, when the mold is opened (i.e., the female element is disengaged from the male element), the abutment element remains in the working position thanks to the locking device. This prevents unnecessary movement of the abutment element from the working position to the resting position when a parison has just been formed and is hanging on the die. This unnecessary movement tends to pull the parison away from the die, causing the parison to detach from the die and / or surface defects on the parison, which are prevented or at least mitigated, as described above.

[0036] The present disclosure also provides a mold configured for forming and blow molding a parison. Preferably, the mold is configured for compression molding the parison from a dose of thermoplastic material. However, the mold may also be configured for injection molding or injection-compression molding the parison.

[0037] The mold comprises a male element according to one or more aspects of the present disclosure. The mold comprises a female element associable with the male element to define a forming cavity for forming a parison. The mold also comprises a blow molding cavity associable with the male element in place of the female element to define a blow molding cavity for forming a container from the parison.

[0038] The mold has a forming configuration (i.e., is operable in the forming configuration) in which the male element is associated with the female element. In the forming configuration, the blow molding cavity is spaced apart from the male element. In embodiments in which there is a stretch rod that is movable relative to the die, the stretch rod is in a retracted position in the forming configuration. In embodiments in which the die is movable relative to the top of the male element, the die is adjacent to the top in the forming configuration.

[0039] The mold has a stretch and blow molding configuration (i.e., is operable in the stretch and blow molding configuration) in which a male element is associated with the blow molding cavity. In the stretch and blow molding configuration, the female element is spaced apart from the male element. In embodiments in which there is a stretch rod that is movable relative to the die, the stretch rod is in an extracted position in the stretch and blow molding configuration. In embodiments in which the die is movable relative to the top of the male element, the die is extracted, i.e., spaced apart, from the top in the stretch and blow molding configuration.

[0040] The mould also has a dose receiving arrangement where the female element is spaced from the male element to receive the dose. Preferably the mould receives the dose from a dose insertion device which inserts the dose into a cavity in the female element. Preferably the dose insertion device ejects the dose into the cavity in the female element.

[0041] Preferably, the male element die is positioned at the same vertical height in the forming configuration as in the stretch and blow molding configuration, while the stretch rod moves downwards after extraction for stretching, so that the parison does not perform a downward movement after forming and before being stretched (in fact, the parison remains attached to the die).

[0042] The present disclosure also provides a forming and blow molding machine comprising a plurality of molds according to one or more aspects of the present disclosure, the machine preferably comprising a rotating carousel having a plurality of molds arranged around a circular periphery of the rotating carousel, preferably evenly spaced apart.

[0043] The present disclosure also provides a method for forming and blow-molding a parison. Preferably, the parison is formed by compression molding. Thus, the method preferably includes receiving a dose of a pre-prepared thermoplastic material into a mold and forming a parison from the dose. In other embodiments, the parison may be formed by injection molding or injection-compression molding.

[0044] The parison is formed in a forming cavity defined by male and female elements of the mold. The male element comprises a die extending along a longitudinal axis and including a body. Preferably, the body has a longitudinal cavity therein extending along the longitudinal axis and a socket at one end thereof in communication with the longitudinal cavity.

[0045] Preferably, the method includes the step of stretching and blow-molding the parison to form the container, wherein the blow-molding includes blowing a stream of air through the passage of the male element.

[0046] Preferably, the male element also comprises a stretch rod slidably inserted into the longitudinal cavity and including an end portion at one end thereof. The stretch rod is movable, i.e., slidable, relative to the die. During the forming step, the stretch rod is in a retracted position, in which the end portion is received in the socket and contributes to defining the forming cavity together with the die. During the drawing step, the stretch rod is in an extended position, in which the end portion is withdrawn from the socket to stretch the parison. Thus, the method includes moving the stretch rod from the retracted position to the extended position.

[0047] Preferably, the method includes the step of cooling the die by passing a cooling fluid through a cooling circuit within the die.

[0048] In one embodiment, the method also includes slowing movement of the stretch rod from the extended position to the retracted position using a damping device.

[0049] In one embodiment, the male element comprises an abutment element configured to abut against the annular periphery of the female element, a support element, and an elastic element connected between the abutment element and the support element. In this embodiment, the method includes moving the abutment element relative to the support element between a rest position in which the elastic element holds the abutment element away from the support element and a working position in which the abutment element contacts the support element. The abutment element is positioned in the working position by the effect of pressure applied to the abutment element by the female element during mold closing. In this embodiment, the method may also include locking the abutment element in the working position using a locking device that engages with the abutment element during mold opening so that the abutment element remains in the working position even when the female element is not applying pressure to the abutment element. Thus, the locking device is removed from the abutment element after the stretching and blow molding steps. [Brief explanation of the drawings]

[0050] These and other features will become more apparent from the following description of preferred embodiments, illustrated by way of non-limiting example in the accompanying drawings, in which: [Figure 1] 1 illustrates a mold according to one or more embodiments of the present disclosure. [Figure 2] FIG. 1 shows the details of the mold. [Figure 3A] 2 shows a detail of the mold of FIG. 1 in the forming configuration and with the stretch rod in the retracted position. [Figure 3B] 2 shows the male element of the mold of FIG. 1 with the stretch rod in the extracted position. [Figure 4] 2 shows the body of the male element of the mold of FIG. 1; [Figure 5] 2 shows an actuation unit for driving the stretch rod of the male element of the mold of FIG. 1; [Figure 6A] 2 shows the mold of FIG. 1 in an open or dose-receiving configuration. [Figure 6C] 2 illustrates the mold of FIG. 1 in a closed or forming configuration. [Figure 6B] 6A and 6C show the mold of FIG. 1 in a configuration intermediate to that shown in FIG. 6A and FIG. 6C. DETAILED DESCRIPTION OF THE INVENTION

[0051] Referring to the accompanying drawings, the numeral 10 designates a mold.

[0052] The mold 10 comprises a male element 100 and a female element 200 which are movable between an open configuration in which they are separated to receive the dose 2 and a closed configuration in which they are brought together to define a forming cavity 20 for forming a parison from the dose 2.

[0053] The mold 10 also includes a blow molding cavity (not shown) that is associable with the male element 100 in place of the female element 200 to form a container from the parison.

[0054] The male element 100 comprises a die 110. The die 110 extends along a longitudinal axis to an end 110A. The die 110 protrudes from the remainder of the male element 100 along the longitudinal axis A. Thus, the die 110 forms a protruding portion of the male element 100 that is configured to be inserted into the female element 200.

[0055] The die 110 has a socket 111 or recess at its longitudinal end 110A. The die 110 has a longitudinal cavity 113 therein that extends along the longitudinal axis A. The longitudinal cavity 113 is in communication with, i.e., open to, the socket 111.

[0056] The male element 100 also includes a stretch rod 120 slidably inserted into the longitudinal cavity 113. The stretch rod 120 has an elongate body extending along the longitudinal axis A and an end portion 121 connected to one end of the elongate body. The end portion 121 is wider than the elongate body. Preferably, the longitudinal cross-section of the end portion 121 gradually widens as it extends away from the elongate body. The stretch rod 120 is movable between a retracted configuration in which the elongate body is inserted into the longitudinal cavity 113 and the end portion 121 is inserted into the socket 111, and an extended position in which the elongate body is partially withdrawn from the longitudinal cavity 113 and the end portion 121 is withdrawn from the socket 111. Note that the end portion 121 is larger in cross-section than the longitudinal cavity 113 and therefore cannot enter the longitudinal cavity 113. Preferably, the distal portion 121 is flared.

[0057] The die 110 also includes a cooling circuit 114 configured to allow circulation of a cooling fluid. The cooling circuit 114 includes a delivery duct 117A for guiding the fluid near the end 110A of the die 110 and a return duct 117B for guiding the fluid returning from the end 110A of the die 110. Preferably, the delivery duct 117A has a first helical shape wound around the longitudinal axis A, and the return duct 117B has a second helical shape wound around the longitudinal axis A. The first and second helices are wound around each other. Thus, at least one turn of the first helix is ​​disposed between two consecutive turns of the second helix, and at least one turn of the second helix is ​​disposed between two consecutive turns of the first helix. The spiral-shaped delivery duct 117A and return duct 117B are arranged in a zone of the die 110 whose cross section converges toward the end 110A. The cooling circuit 114 also includes a delivery manifold 117A' connected to the delivery duct 117A for consolidating the flow of cooling fluid, and a return manifold 117B' connected to the return duct 117B for extracting cooling fluid therefrom. The delivery manifold 117A' and the return manifold 117B' extend parallel to the longitudinal axis A. The cooling fluid thus flows down the delivery manifold 117A', along the delivery duct 117A until near the end 110A of the die 110, and then along the return duct 117B and up the return manifold 117B'.

[0058] In the connection zone between the delivery duct 117A and the return duct 117B, there is an O-ring surrounding the longitudinal cavity 113, close to the end 110A of the die 110, to prevent leakage of the cooling fluid.

[0059] Preferably, the die 110 includes a body 112. The die 110 also includes a liner 116 mounted around the body 112. A delivery duct 117A and a return duct 117B are formed between the body 112 and the liner 116. More specifically, the body 112 is grooved to create recesses that, together with corresponding interior surfaces of the liner 116, define a duct system 117. The duct system 117 defines ducts 117A and 117B for cooling fluid. The body 112 also has a groove-free zone that defines a support surface 112A on which the liner 116 is supported. Preferably, the support surface 112A is defined between each turn of the delivery duct 117A and an adjacent turn of the return duct 117B.

[0060] Note that the stretch rod 120 is spaced apart from the wall of the body 112 that defines the longitudinal cavity 113. Thus, there is a gap 115 between the stretch rod and the wall of the body 112 that defines the longitudinal cavity 113. The gap 115 has a tubular shape around the stretch rod 120. In the illustrated embodiment, the gap 115 is wider in a zone away from the end 110A of the die 110 and narrower in a zone closer to the end 110A of the die 110. The gap 115 is configured to direct the air flow used to blow the parison. In practice, once the parison is formed, it is blown to form a container. The gap 115 extends along the longitudinal axis A to the socket 111 and has an outlet 115A through which the blowing air is released.

[0061] When the stretch rod 120 is in the retracted position, the end portion 121 blocks the outlet 115 A. When the stretch rod 120 is in the extended position, the outlet 115 A is open, allowing the blow molding air to flow from the gap 115.

[0062] The stretch rod 120 is connected at its end opposite the terminal portion to a diffuser rod 122. The diffuser rod 122, which also forms part of the male element 100, extends along a longitudinal axis A between a first end 122A connected to the stretch rod 120 and a second end 122B opposite the first end 122A. The first end 122A defines a lead nut into which the threaded end of the stretch rod 120 is threaded. The diffuser rod 122 is thus integrally connected to the stretch rod 120. Preferably, the diffuser rod 122 is larger in cross section than the stretch rod 120.

[0063] The second end 122B of the diffuser rod 122 is connected to an actuation unit 130 configured to move the diffuser rod 122 and the extension rod 120. More specifically, the actuation unit 130 moves the extension rod 120 between a retracted position and an extended position.

[0064] In one embodiment, the male element 100 or mold 10 includes a damping device 140 connected to the second end 122B of the diffuser rod 122. The damping device 140 may, for example, include a spring wound around the second end 122B of the diffuser rod 122. The damping device 140 is configured to damp movement of the diffuser rod 122 corresponding to movement of the stretch rod 120 from the extended position to the retracted position. This prevents an impact between the end 122B of the diffuser rod 122 and the actuation unit 130 from destroying the diffuser rod 122 and / or the stretch rod 120, and / or the threaded connection between the diffuser rod 122 and the stretch rod 120.

[0065] In one embodiment, the male element 100 also comprises an abutment element 11 that surrounds the die 110 and is configured to abut against the annular periphery of the female element 200 when the mold 10 is closed, i.e., in the forming configuration of the mold 10. The male element 100 also comprises a support element 12 and an elastic element 13 (e.g., a spring), the abutment element 11 being connected to the support element 12 by the elastic element 13. The elastic element 13 tends to keep the abutment element 11 away from the support element 12 when at rest.

[0066] When the mold 10 closes, the female element 200 moves into contact with the abutment element 11 and exerts pressure thereon, bringing the abutment element 11 closer to the support element 12, thereby compressing the elastic element 13. A displacement s1 of the female element 200 towards the male element 100 therefore results in a displacement s2 of the abutment element 11 towards the support element 12, s2 being smaller than s1. In this way, contact with the male element 100 is guaranteed even if the stroke of the female element 200 is not exactly matched.

[0067] To prevent the abutment element 11 from separating from the support element 12 and the parison from leaving the die 110 when the female element 200 separates from the male element 100 after the parison has been formed, the male element 100 is provided with a locking device configured to mechanically engage with the abutment element 11. Thanks to the locking device, the abutment element 11 remains stationary relative to the support element 12 and the spring of the elastic element 13 remains compressed even when the female element 200 separates from the abutment element 11.

[0068] The following paragraphs, listed in alphanumeric order for reference, are non-limiting exemplary modes of describing the present invention. A. A male element (100) of a mold (10) for compression molding a parison from a dose (2) of pre-prepared thermoplastic material, the male element (100) being associable with a female element (200) of the mold (10) to define a forming cavity (20) for forming the parison, the male element (100) comprising a die (110) extending along a longitudinal axis (A), the die (110) including a body (112). A1. The male element of paragraph A, comprising a passageway for air flow for blowing the parison to form the container. A1.1. The male element described in paragraph A1, wherein the die has a longitudinal cavity (113) therein extending along the longitudinal axis (A) and a socket (111) at one end thereof communicating with the longitudinal cavity (113), and the male element comprises a stretch rod (120) slidably inserted into the longitudinal cavity (113), the stretch rod (120) having an end portion (121) at one end thereof, the stretch rod (120) being movable relative to the die (110) between a retracted position in which the end portion (121) is received within the socket (111) and contributes to defining the forming cavity (20) together with the die (110), and an extended position in which the end portion (121) is withdrawn from the socket (111) to stretch the parison. A1.1.1. The male element described in paragraph A1.1, wherein the passage for the air flow comprises a gap (115) formed by a portion of the longitudinal cavity (113) between the outer surface of the stretch rod (120) and the inner surface of the die (110) that defines the longitudinal cavity (113). A1.1.1.1. A male element as described in paragraph A1.1.1, wherein the gap (115) extends to the socket (111) and has an outlet (115A) therein to allow air flow to escape, and wherein an end portion (121) of the stretch rod (120) is spaced from the socket (111) such that, in the retracted position, it blocks the outlet (115A) to prevent air from flowing from the gap (115) into the forming cavity (20), and in the extended position, the outlet (115A) is open to allow air to flow from the gap (115), and the gap (115) preferably has a tubular shape surrounding the stretch rod. A1.2. an actuation unit (130) configured to drive movement of the extension rod (120) from the extended position to the retracted position and from the retracted position to the extended position; The male element of any one of paragraphs A1.1 to A1.1.1.1, comprising a damping device (140) associated with the actuation unit (130) and configured to slow the movement of the extension rod (120) from the extended position to the retracted position. A1.2.1. a diffuser rod (122) extending between a first end (122A) connected to the extension rod (120), preferably by a threaded connection, and a second end (122B) opposite the first end (122A); the actuation unit (130) is connected to the second end (122B) of the diffuser rod (122) and is configured to move the diffuser rod (122) between a first position corresponding to the extended position of the extension rod (120) and a second position corresponding to the retracted position of the extension rod (120); The male element described in paragraph A1.2, wherein the damping device (140) is attached to the second end (122B) of the diffuser rod (122) and is configured to slow movement of the diffuser rod (122) from the first position to the second position. A1.2.1.1. The male element of paragraph A1.2.1, wherein the damping device (140) includes a spring attached to the second end (122B) of the diffuser rod (122). A2. The male element of paragraph A or A1, further comprising an upper portion, wherein the die (110) is retractable relative to the upper portion so as to be movable between a retracted position where the die (110) contributes to defining the forming cavity (20) together with the upper portion, and an extended position configured to stretch the parison. A3. The male element of any of paragraphs A-A2, wherein the die (110) includes a cooling circuit (114) configured to allow a cooling fluid to flow therethrough. A3.1. The male element described in paragraph A3, wherein the cooling circuit includes a delivery duct for circulating cooling fluid toward the end of the die and a return duct for circulating cooling fluid back from the end of the die, the return duct being connected in series with the delivery duct. A3.1.1. The male element described in paragraph A3.1, wherein the delivery duct (117A) has a first helical shape wound around the longitudinal axis (A) and the return duct (117B) has a second helical shape wound around the longitudinal axis (A), and at least one turn of the first helix is ​​disposed along the longitudinal axis (A) between a first turn and a second turn of the second helix. A3.1.2. The male element of paragraph A3.1 or A3.1.1, wherein the die (110) comprises a liner (116) mounted around the body (112), the liner (116) having an outer surface that cooperates with the female element (200) of the mold (10) to define the forming cavity (20) and an inner surface that contacts the outer surface of the body (112), and the cooling circuit comprises a duct system (117) formed between the body (112) and the liner (116). A3.1.2.1. The male element described in paragraph A3.1.2, wherein the outer surface of the body (112) is grooved to form a recessed surface (112A) that acts with a corresponding portion of the inner surface of the liner (116) to define a duct system (177). A4. an abutment element (11) configured to abut against the annular periphery of the female element (200); a support element (12); an elastic element (13) connected between the abutment element (11) and the support element (12), the abutment element (11) being movable relative to the support element (12) between a rest position in which the elastic element (13) keeps the abutment element (11) spaced apart from the support element (12) and a working position in which the abutment element (11) is in contact with the support element (12), the abutment element (11) being able to be placed in the working position by the effect of pressure exerted on the abutment element (11) by the female element (200); The male element of any of paragraphs A to A3.1.2.1., wherein the mold (10) also includes a locking device configured to engage with the abutment element (11) to keep the abutment element in a working position even when the female element no longer exerts pressure on the abutment element. A4.1. The male element according to paragraph A4, wherein the locking device is movable between a locked position in which it engages the abutment element and a rest position in which it is released from the abutment element. B00. A mold (10) for forming a parison from a quantity of thermoplastic material, comprising: A male element (100) according to any of paragraphs A to A4.1; a female element (200) associable with the male element (100) to define a forming cavity (20) for forming a parison from the dose (2); The mold (10) has a forming configuration in which a male element (100) is associated with a female element (200) to form a parison within a forming cavity (20). B01. A mold (10) according to paragraph B00 for injection molding of a parison. B02. A mold (10) according to paragraph B00 for compression molding of a parison, in which a predetermined amount of thermoplastic material forms a dose from a dose (2) of thermoplastic material (the dose being processable). B. A mold (10) for compression molding a parison from a dose (2) of thermoplastic material, comprising: A male element (100) according to any of paragraphs A to A4.1; a female element (200) associable with the male element (100) to define a forming cavity (20) for forming a parison from the dose (2); The mold (10) has a forming configuration in which a male element (100) is associated with a female element (200) to form a parison within a forming cavity (20). B1. The mold (10) of paragraph B or B00 or B01 or B02, comprising a blow molding cavity associable with a male element (100) instead of a female element (200) to define a blow molding cavity in which a container is formed from a parison, the mold having a stretch and blow molding configuration in which the male element (100) is associated with the blow molding cavity to stretch and blow mold the parison. C. 1. A method for compression molding and blow molding a parison, comprising: receiving a dose (2) of pre-prepared thermoplastic material in a mold (10); forming a parison from the dose (2) in a forming cavity defined by a male element (100) and a female element (200) of a mold (10), the male element (100) comprising a die (110) extending along a longitudinal axis (A), the die (110) including a body (112); stretching and blow-molding the parison to form a container. C1. The method of paragraph C, comprising cooling the die (110) by passing a cooling fluid through a cooling circuit (114) within the die. C2. The method of paragraph C or C1, wherein the body has a longitudinal cavity (113) therein extending along the longitudinal axis (A) and a socket (111) at one end thereof communicating with the longitudinal cavity, the male element comprising a stretch rod (120) slidably inserted into the longitudinal cavity (113), the stretch rod (120) including an end portion at one end thereof, the method including the step of moving the stretch rod between a retracted position in which the end portion (121) is received within the socket (111) and contributes to defining the forming cavity (20) together with the die (110), and an extraction position in which the end portion (121) is withdrawn from the socket (111) to stretch the parison. C2.1. The method of paragraph C2, wherein blow molding includes blowing an air stream into a passage of the male element (100), the passage of the air stream including a gap (115) formed by a portion of the longitudinal cavity (113) between the outer surface of the stretch rod and the inner surface of the die that defines the longitudinal cavity. C2.2. The method of paragraph C2 or C2.1, including using a damping device to slow movement of the extension rod from the extended position to the retracted position. C3. The male element is an abutment element (11) configured to abut against the annular periphery of the female element (200); a support element (12); an elastic element (13) connected between the abutment element (11) and the support element (12); The method comprises the steps of moving the abutment element (11) relative to the support element (12) between a rest position in which the elastic element (13) keeps the abutment element (11) spaced from the support element (12) and a working position in which the abutment element (11) is in contact with the support element (12), the abutment element (11) being placed in the working position by the effect of pressure exerted on the abutment element (11) by the female element (200) during closing of the mould; The method of any of paragraphs C to C2.2, wherein the method includes locking the abutment element in a working position using a locking device that engages with the abutment element, so that the abutment element remains in the working position even when the female element is not applying pressure to the abutment element while the mold is being opened. [Prior art documents] [Patent documents]

[0069] [Patent Document 1] WO2008 / 110887A2 [Patent Document 2] WO2007107822A2 [Patent Document 3] US10781010B2 [Patent Document 4] US8790112B2 [Patent Document 5] CH431030A [Patent Document 6] US2012100241A1 [Patent Document 7] US4150689A [Patent Document 8] US4473515A

Claims

1. a male element (100) of a mold (10) for compression-molding a parison from a dose (2) of thermoplastic material prepared in advance, said male element (100) being connectable with a female element (200) of said mold (10) to define a forming cavity (20) for molding said parison; The male element (100) is A die (110) extending along a longitudinal axis (A), the die (110) including a body (112) having a longitudinal cavity (113) therein extending along said longitudinal axis (A), and a socket (111) at one end thereof communicating with said longitudinal cavity (113); a stretch rod (120) slidably inserted into the longitudinal cavity (113), the stretch rod (120) including an end portion (121) at one end thereof, the stretch rod (120) being movable relative to the die (110) between a retracted position in which the end portion (121) is received in the socket (111) and contributes to defining the forming cavity (20) together with the die (110), and an extended position in which the end portion (121) is withdrawn from the socket (111) to stretch the parison; an airflow passage for blowing the parison to form a container; the die (110) includes a cooling circuit (114) therein configured to allow a flow of a cooling fluid; The cooling circuit (114) is configured to allow circulation of a cooling fluid and includes a delivery duct (117A) for guiding the cooling fluid to near an end (110A) of the die (110) and a return duct (117B) for guiding the cooling fluid back from the end (110A) of the die (110); The male element (100) comprises an actuation unit (130) configured to drive the movement of the stretch rod (120) from the extended position to the retracted position and from the retracted position to the extended position; a damping device (140) associated with the actuation unit (130) and configured to slow the movement of the extension rod (120) from the extended position to the retracted position; The male element (100) comprises a diffuser rod (122) extending between a first end (122A) connected to the stretch rod (120) and a second end (122B) opposite the first end (122A); the actuation unit (130) is connected to the second end (122B) of the diffuser rod (122) and is configured to move the diffuser rod (122) between a first position corresponding to the extended position of the stretch rod (120) and a second position corresponding to the retracted position of the stretch rod (120); the damping device (140) is attached to the second end (122B) of the diffuser rod (122) and is configured to slow movement of the diffuser rod (122) from the first position to the second position.

2. 2. The male element (100) of claim 1, wherein the passage for the air flow comprises a gap (115) formed by a portion of the longitudinal cavity (113) between an outer surface of the stretch rod (120) and an inner surface of the die (110) that defines the longitudinal cavity (113).

3. 3. The male element (100) of claim 2, wherein the gap (115) extends to the socket (111) and has an outlet (115A) therein for allowing the air flow to be discharged, and wherein the end portion (121) of the stretch rod (120) is spaced from the socket (111) such that, in the retracted position, it blocks the outlet (115A) to prevent air from flowing from the gap (115) into the forming cavity (20), and in the extended position, the outlet (115A) is open to allow air to flow from the gap (115).

4. 4. The male element (100) of claim 3, wherein said gap (115) has a tubular shape surrounding said stretch rod (120).

5. 5. The male element (100) according to any one of claims 1 to 4, wherein the damping device (140) comprises a spring attached to the second end (122B) of the diffuser rod (122).

6. 6. The male element (100) according to any one of claims 1 to 5, wherein the stretch rod (120) is connected to the first end (122A) of the diffuser rod (122) by a threaded connection.

7. 7. The male element (100) according to any one of claims 1 to 6, wherein the cooling circuit (114) comprises a delivery duct (117A) for circulating the cooling fluid towards an end of the die (110) and a return duct (117B) for circulating the cooling fluid back from the end of the die (110).

8. 8. The male element according to claim 7, wherein the return duct is connected in series with the delivery duct, the delivery duct having the shape of a first spiral wound around the longitudinal axis, and the return duct has the shape of a second spiral wound around the longitudinal axis, and wherein at least one turn of the first spiral is disposed along the longitudinal axis between a first turn and a second turn of the second spiral.

9. an abutment element (11) configured to abut against the annular periphery of said female element (200); a support element (12); an elastic element (13) connected between the abutment element (11) and the support element (12), said abutment element (11) being movable relative to said support element (12) between a rest position and a working position, in which said elastic element (13) keeps said abutment element (11) spaced apart from said support element (12), and in which said abutment element (11) is in contact with said support element (12), said abutment element (11) being able to be placed in said working position by the effect of pressure exerted on said abutment element (11) by said female element (200); 9. A male element (100) according to any one of claims 1 to 8, wherein the mold (10) also comprises a locking device configured to engage with the abutment element (11) so as to hold the abutment element (11) in the working position even when the female element (200) is no longer exerting pressure on the abutment element (11).

10. A mold (10) for compression molding a parison from a dose (2) of thermoplastic material and for blow molding said parison, A male element (100) according to any one of claims 1 to 9, a female element (200) associable with said male element (100) to define said forming cavity (20) for forming said parison from said dose (2); a blow moulding cavity associable with said male element (100) in place of said female element (200) to define a blow moulding cavity for forming a container from said parison; The mold (10) has a forming configuration in which the male element (100) is associated with the female element (200) and the stretch rod (120) is in the retracted position to form the parison in the forming cavity (20), and a stretch and blow molding configuration in which the male element (100) is associated with the blow molding cavity and the stretch rod (120) is in the extended position.

11. 11. The mold (10) of claim 10, also comprising a configuration for receiving the dose (2), wherein the female element (200) is spaced from the male element (100) for receiving the dose (2).

12. 12. A mold (10) according to claim 10 or 11, wherein the die (110) of the male element (100) is arranged at the same vertical height in the forming configuration as in the stretch and blow molding configuration.

13. 1. A forming and blow molding machine, comprising: A rotating carousel, 13. A forming and blow molding machine comprising a plurality of moulds (10) according to any one of claims 10 to 12, the moulds (10) being angularly equally spaced around the circular periphery of the rotating carousel.

14. 1. A method for compression molding and blow molding a parison, comprising: receiving a dose (2) of pre-prepared thermoplastic material in a mould (10); forming said parison from said dose (2) in a forming cavity defined by a male element (100) and a female element (200) of said mold (10), said male element (100) comprising a die (110) extending along a longitudinal axis (A), said die (110) comprising a body (112); stretching and blow-molding the parison to form a container, the blow-molding comprising blowing a stream of air through a passage of the male element (100); the male element (100) comprises a stretch rod (120) slidably inserted into the longitudinal cavity (113), the stretch rod (120) including an end portion (121) at one end thereof, the stretch rod (120) being movable relative to the die (110), and in the forming step, the stretch rod (120) is in a retracted position in which the end portion (121) is received in a socket (111) and contributes to defining the forming cavity (20) together with the die (110), and in the drawing step, the stretch rod (120) is in an extended position in which the end portion (121) is drawn out of the socket (111) so as to stretch the parison; The method includes the steps of: cooling the die (110) by passing a cooling fluid through a cooling circuit (114) configured to allow circulation of the cooling fluid within the die (110), wherein an outlet duct (117A) of the cooling circuit (114) guides the cooling fluid to near an end (110A) of the die (110), and a return duct (117B) of the cooling circuit (114) guides the cooling fluid returning from the end (110A) of the die (110); moving a diffuser rod (122) extending between a first end (122A) connected to the stretch rod (120) and a second end (122B) opposite the first end (122A) between a first position corresponding to the extended position of the stretch rod (120) and a second position corresponding to the retracted position of the stretch rod (120); slowing the movement of the diffuser rod (122) from the first position to the second position.

15. 15. The method of claim 14, wherein the passage in the male element (100) for the air flow comprises a gap (115) formed by a portion of the longitudinal cavity (113) between an outer surface of the stretch rod (120) and an inner surface of the die that defines the longitudinal cavity (113).

16. a male element (100) of a mold (10) for compression-molding a parison from a dose (2) of thermoplastic material prepared in advance, said male element (100) being connectable with a female element (200) of said mold (10) to define a forming cavity (20) for molding said parison; The male element (100) is A die (110) extending along a longitudinal axis (A), the die (110) including a body (112) having a longitudinal cavity (113) therein extending along said longitudinal axis (A), and a socket (111) at one end thereof communicating with said longitudinal cavity (113); a stretch rod (120) slidably inserted into the longitudinal cavity (113), the stretch rod (120) including an end portion (121) at one end thereof, the stretch rod (120) being movable relative to the die (110) between a retracted position in which the end portion (121) is received in the socket (111) and contributes to defining the forming cavity (20) together with the die (110), and an extended position in which the end portion (121) is withdrawn from the socket (111) to stretch the parison; an airflow passage for blowing the parison to form a container; the die (110) includes a cooling circuit (114) therein configured to allow a flow of a cooling fluid; The male element (100) is an abutment element (11) configured to abut against the annular periphery of said female element (200); a support element (12); an elastic element (13) connected between the abutment element (11) and the support element (12), said abutment element (11) being movable relative to said support element (12) between a rest position and a working position, in which said elastic element (13) keeps said abutment element (11) spaced apart from said support element (12), and in which said abutment element (11) is in contact with said support element (12), said abutment element (11) being able to be placed in said working position by the effect of pressure exerted on said abutment element (11) by said female element (200); The mold (10) also comprises a male element (100) which is characterized in that it comprises a locking device configured to engage with the abutment element (11) so as to hold the abutment element (11) in the working position even when the female element (200) is no longer exerting pressure on the abutment element (11).

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