Abstract: An in-mold shutter (140) for embedding in an injection mold (100, 200, 300) is described herein. The in-mold shutter (140, 240, 340, 440, 540) includes a shutter actuator (148, 548) that is configured to selectively engage a first mold shoe (130) of the injection mold (100, 200, 300) with a platen of a mold clamping assembly (996) to hold the first mold shoe (130) in an extended position (E), along a mold-stroke axis (X), during a step of molding a first molded article (102A) in the injection mold (100, 200, 300). Also described herein is a molded article transfer device (150, 250) for use with the injection mold (100, 200, 300). The molded article transfer device (150, 250) includes a shuttle (154) that is slidably arranged, in use, within the injection mold (100, 200, 300).

Abstract: An apparatus includes a transferring arrangement for transferring objects obtained by compression-molding doses of synthetic plastics from a forming arrangement of a forming unit and a supporting arrangement for rotatably supporting the transferring arrangement. In order to avoid blows and/or damage between the transferring arrangement and the forming arrangement, the apparatus includes a moving arrangement connected to the supporting arrangement and configured for moving the transferring arrangement at least between a first operating position nearer the forming unit, in which the transferring arrangement interacts with the forming arrangement to transfer the objects, and a second operating position, in which the transferring arrangement is spaced away from the forming unit so as not to interact with the forming arrangement.

Abstract: An apparatus for transferring objects (2), in particular caps (2), from a molding carousel (3) on which the caps (2) are molded, to an evacuating device (6), comprises: —a supporting element (11) that is rotatable around a rotation axis (X1) and is suitable for receiving said objects (2) and, —arm means (13) that is rotatable around said rotation axis (X1) and comprising seat means (16) that is suitable for receiving said caps (2); the arm means (13) is movable so as to vary the distance of the arm means (13) from said rotation axis (X1), in particular it is movable radially with respect to the rotation axis (X1) to slide the objects (2) on the supporting element (11).

Abstract: A spray assembly includes a power source, a motion control mechanism such as a cam box, and at least one spray head structured to apply a coating to a plurality of can ends. Each spray head includes a mounting member, a pivot member, a gun assembly including a plurality of spray guns, and a transfer mechanism for transferring a predetermined motion induced by the cam box from the cam box to the pivot member. Each of the spray guns applies the coating to the can ends in accordance with the predetermined motion. Preferably the predetermined motion as an oscillating motion transferred to the pivot member by belts, thereby oscillating the spray guns. The spray assembly may include a plurality of spray heads, wherein can ends of the same or different sizes are transferred in lanes to a corresponding one of the spray heads.

Abstract: Described herein is a mold. The mold includes a first mold half and a second mold half. A molding cavity is definable between the first mold half and the second mold half within which a molded article is moldable. The mold also includes a core configured to form a seal on the molded article. The first mold half and the second mold half are configured to remain in a mold closed configuration with molding and stripping of the molded article.

Abstract: A safety device for an apparatus for compression-moulding objects that includes a moulding carousel provided with a plurality of punches and with a plurality of corresponding moulding elements, each mould element being movable between a first position in which it does not interact with the respective punch and a second position in which it interacts with the respective punch to mould an object. Each punch is associated with an extracting device suitable for extracting from the respective punch a moulded object. The extracting device is driven by a cam track obtained in a fixed frame of the moulding carousel. The cam track includes a cam track portion that is movable between an operating position in which it interacts with the extracting device and a non-operating position in which it does not interact with the extracting device.

Abstract: Described herein is a mold. The mold includes a first mold half and a second mold half. A molding cavity is definable between the first mold half and the second mold half within which a molded article is moldable. The mold also includes a core configured to form a seal on the molded article. The first mold half and the second mold half are configured to remain in a mold closed configuration with molding and stripping of the molded article.

Abstract: An apparatus comprising a transferring element for transferring a dose of flowable material, said dose being provided with an elongated body having a transverse dimension and an end zone, a receiving member for receiving said dose from said transferring element, wherein said transferring element comprising an end-forming arrangement for forming said end zone in such a way as to decrease said transverse dimension in the vicinity of said end zone. A dose of plastics comprises an elongated body provided with a transverse dimension, said elongated body comprising an end zone provided with a respective transverse dimension that is less than said transverse dimension.

Abstract: A container closer includes a cap and a seal liner coupled to the cap. The cap is configured to mount on a filler neck of a container to mate the seal liner with a brim of the filler neck.

Abstract: An apparatus comprises an extruding device having a dispensing opening for extruding a flowable material along an exit direction through the dispensing opening, and a cutting arrangement for separating a dose from the flowable material, the cutting arrangement being movable with a motion component that is parallel to the exit direction.

Abstract: An apparatus comprises: forming means movable along a first path for compression moulding doses of plastics; a plurality of transfer means for transferring said doses to said forming means; a plurality of arm means, each arm means being associated with a corresponding transfer means for moving said transfer means along a second path having a portion substantially coinciding with a further portion of said first path.

Abstract: A collapsible core device for molding articles around the core device in a mold cavity includes an expansion member, a discontinuous first sleeve and a discontinuous second sleeve. When the expansion member is fitted within the first and second sleeves, the expansion member and the first and second sleeves form a substantially continuous, flush top molding surface with the first and second sleeves.

Abstract: In one embodiment of the present invention, an assembly for HPHT processing comprises a can with an opening. A powder mixture is disposed within the opening. A substrate is disposed within the opening adjacent the powder mixture. Paint is coated on a surface within the opening and opposite the powder mixture with respect to the substrate. A meltable sealant is disposed within the opening and opposite the substrate with respect to the surface and a cap is covering the opening.

Abstract: An apparatus for supplying synthetic resins applicable to a metal mold wheel that rotates at a high speed. A cutter of a cutter unit and a holding fitting are attached to an air cylinder, so that the cutter unit can be advanced and retreated in the radial direction of rotation. When the molten resin is stably blown out from an extrusion nozzle, the air cylinder is expanded to move the cutter to an advanced position to cut the molten resin. When the molten resin is unstably blown out from the extruder, the air cylinder is contracted and the cutter is arranged at a retreated position so will not to come in contact with the molten resin. Despite the cutter wheel continues to rotate, the molten resin is not contacted by the cutters.

Abstract: An apparatus comprises a forming device for forming objects, a moving arrangement arranged for moving said objects along a path directed from said forming device towards an exit area, passage arrangement for an operating fluid, said passage arrangement being arranged for allowing said objects to be moved towards said exit area at least in a preset portion of said path. A method comprises forming objects, moving said objects along a path directed towards an exit area, and acting on said objects with an operating fluid at least in a preset portion of said path, so as to allow said objects to be moved towards said exit area.

Abstract: A mold core includes a forming pin having a hollow interior and an end wall. A passage, preferably in the form of a hollow tube, extends into the hollow interior of the forming pin and has an end sealingly secured at a position spaced from the end wall of the forming pin. A poppet valve is disposed on the end wall of the forming pin. The poppet valve is responsive to air pressure within the passage to open and permit flow of air through the end wall of the forming pin to assist stripping of molded articles from the mold core. The poppet valve includes a valve element having an outer end at the end face of the forming pin and an inner end adjacent to the end of the passage. A spring preferably biases the valve element to a closed position. The spring preferably comprises a coil spring captured in compression between the valve element and the forming pin.

Abstract: In one embodiment of the present invention, an assembly for HPHT processing comprises a can with an opening. A powder mixture is disposed within the opening. A substrate is disposed within the opening adjacent the powder mixture. Paint is coated on a surface within the opening and opposite the powder mixture with respect to the substrate. A meltable sealant is disposed within the opening and opposite the substrate with respect to the surface and a cap is covering the opening. In another embodiment of the present invention, an assembly for HPHT processing comprises a can with an opening, a powder mixture is disposed within the opening, a substrate disposed within the opening adjacent and above the powder mixture, a formable sealant barrier is disposed within the opening above the substrate, a meltable sealant is disposed within the opening above the formable sealant barrier, and a cap covers the opening.

Abstract: A closure cap and method of making the same wherein an annular or ring-shaped gasket is injection molded onto the inner surface of a cap shell formed of plastic or metal. The annular or ring-shaped gasket includes at least one radially extending tab integrally formed therewith. A channel in the working surface of a mold core cooperates with the inside surface of the cap to form a mold cavity having the shape of the gasket to be formed therein. The cavity includes a melt inlet and a melt outlet which is in flow communication with a cold well through a connecting portion of reduced cross-sectional area with respect to the cross-sectional areas of both the gasket-defining mold cavity and the cold well.

Abstract: An apparatus for making a fracture cut between the cup and the safety ring in plastic caps, which comprises rotary elements provided with at least one mandrel that can be arranged inside the cup and is suitable to produce the rolling, about its own axis of symmetry, of the side wall of the cup along the cutting edge of a blade for making the cut, the blade being associated with an inlet path portion adapted to axially offset the cup with respect to the rotation axis of the mandrel by clamping the side wall against the mandrel; the apparatus also comprises elements for recentering the cup with respect to the rotation axis.

Abstract: A machine for compression molding plastic articles includes a turret constructed for rotation around a vertical axis. A first array of compression molds and a second array of compression molds are mounted on the turret for movement through respective first and second mold paths as the turret rotates around the vertical turret axis. A first mold charge placement mechanism is disposed adjacent to the first path for placing mold charges into molds of the first array in sequence as the turret rotates. A second mold charge placement mechanism is disposed adjacent to the second path for placing mold charges into molds of the second array in sequence as the turret rotates and independently of the first mechanism. The first and second mold paths may be spaced from each other radially of the turret axis and/or longitudinally of the turret axis.

Abstract: An apparatus for placing a mold charge into a mold of a compression molding machine includes a carrier mounted for rotation around a first axis, at least one arm mounted on the carrier for rotation around a second axis at an angle to the first axis, and a mold charge pick-up cup on the arm for receiving a mold charge, transporting the mold charge and placing the mold charge into a mold of the compression molding machine. A cam is carried in stationary position adjacent to the carrier surrounding the first axis, and a cam follower is operatively coupled to the arm in engagement with the cam for rotating the arm and the mold charge pick-up cup around the second axis as the carrier is rotated around the first axis.

Abstract: Embodiments of the invention provide a method and apparatus for manufacturing dental aligners. The system includes a workpiece introduction system having at least one workpiece preparation chamber. The system further has a mold manipulation system, having a mold introduction chamber, where a series of different molds may be introduced one after the other; a mold preparation chamber; a workpiece operation chamber; and a mold manipulator to move the mold between the mold introduction chamber, the mold preparation chamber, and the workpiece operation chamber; and a workpiece manipulator to move the workpiece between the workpiece preparation chamber and the workpiece operation chamber.

Abstract: An apparatus for compression molding sealing liners in premade closure shells includes a shell loader for presenting premade closure shells in sequence, a mold charge placement device for placing charges of liner material into the premade shells, and a vertical wheel molding machine for receiving the closure shells in sequence from the loader and compression molding the mold charges to form sealing liners within the closure shells. The vertical wheel molding machine preferably includes a wheel mounted for rotation around a horizontal axis and a plurality of angularly spaced molds disposed around the wheel. Each of the molds preferably includes a first mold segment and a second mold segment disposed radially outwardly of the first mold segment. One of the first and second mold segments, preferably the second mold segment, includes a nest for receiving a premade closure shell.

Abstract: A machine for compression molding plastic articles includes an array of compression molds mounted on a support for movement through a defined mold path. A cam is disposed adjacent to the support to engage the molds in sequence and move at least one segment of each mold between open and closed positions. The cam has a first portion for opening the molds, a second portion for closing the molds in sequence and a pivot mounting the second cam portion to the first cam portion. A latch holds the second cam portion in a first position for closing the molds in sequence, and is responsive to excess force on the second cam portion to release said second cam portion to pivot to a second position spaced from the path.

Abstract: A mold core includes a forming pin having a hollow interior and an end wall. A passage, preferably in the form of a hollow tube, extends into the hollow interior of the forming pin and has an end sealingly secured at a position spaced from the end wall of the forming pin. A poppet valve is disposed on the end wall of the forming pin. The poppet valve is responsive to air pressure within the passage to open and permit flow of air through the end wall of the forming pin to assist stripping of molded articles from the mold core. The poppet valve includes a valve element having an outer end at the end face of the forming pin and an inner end adjacent to the end of the passage. A spring preferably biases the valve element to a closed position. The spring preferably comprises a coil spring captured in compression between the valve element and the forming pin.

Abstract: A plastic closure for sealing a container, the closure having a top portion and a skirt portion depending from the top portion. The closure has an annular sealing rib which extends within the cavity defined by the top portion and the skirt portion. The rib includes a first portion having a substantially cylindrical inner surface extending away from the underside of the top portion and disposed radially inward of the skirt and a second, frusto-conical, portion contiguous with the end of the first portion distal to the underside of the top portion and extending radially inwardly and terminating in a circular free edge, such that during engagement of the cap with the neck of the container, the second, frusto-conical, portion will be engaged by the free end of the neck and folded back against the first portion of the rib to form a gas-tight seal between the neck of the container and the closure.

Abstract: A compression molding machine, for compression molding a closure shell having a base wall with an opening and in accordance with one aspect of the disclosure, includes a male mold section and a female mold section having associated surfaces that oppose each other to form a cavity for compression molding the base wall of the closure shell. An annular bead on one of these surfaces cooperates with the opposing other surface to compression mold a disk connected to the base wall by a thin frangible web. The disk and the shell are stripped separately from the mold so that the shell emerges from the machine with the opening formed in the shell base wall by removal of the disk within the machine.

Abstract: A method for separating a portion of extruded material from the continuous strip leaving an extruder, consisting of passing in front of the extrusion nozzle withdrawal means associated with at least one cutting means; said withdrawal means and said at least one cutting means are made to move independently of each other with velocities, in the sense of vectors, which differ from each other and differ in relation to the material portion separated.

Abstract: Apparatus for compression molding plastic articles includes a plurality of molds mounted for travel around a first axis. Each mold includes an upper mold section and a lower mold section, with at least one of the upper and lower mold sections being moveable in a non-circular first endless path, and being moveable with respect to the other mold section to form a mold cavity. A mold charge delivery system delivers individual mold charges to the mold cavities and includes at least one delivery mechanism that travels in a second endless path around a second axis spaced from the first axis, wherein the second endless path overlies a portion of the first endless path.

Abstract: A method and apparatus for compression molding plastic articles include a plurality of tools mounted in opposed pairs with the tools of each pair including opposed first and second actuators that define a mold cavity in which a charge of plastic is compression molded. The tooling is preferably carried by a rotary turret so that first and second actuators of each tooling pair are moveable relative to each other between an open position permitting formed articles to be removed from the tooling and to receive fresh charges of plastic, and a closed position to compression mold the charges of plastic.

Abstract: A device for removing doses of plastic material from the outflow orifice of an extruder by means of at least one removal element movable with respect to the extruder and provided with a receptacle for a dose removed from the orifice, the removal element comprising a severing element adapted to cut into the plastic material dispensed by the extruder along a severing edge advancing through the material from one side of the orifice to the other, the receptacle being shaped so as to accomodate the dose and allow its expulsion substantially in the directon of the severing edge.

Abstract: An apparatus for inverting the stop flange on a tamper-indicating closure, from an axially outwardly oriented position as molded to an axially inwardly oriented position for use, includes a support base for supporting the closure such that the stop flange as molded is spaced from and oriented away from the support base. A pedestal is movably carried by the support base at a position spaced from the support base. A locator ring is carried by the pedestal and movable with the pedestal to engage the stop flange on a closure carried by the support base and to bend the stop flange radially inwardly. An inversion ring moves through the locator ring to engage and invert the stop flange that is bent radially inwardly by the locator ring.

Abstract: An apparatus for compression molding of articles made of plastics, comprising: molding means; feeding means for feeding doses of plastic material, which are provided with removal elements for removing in succession said doses from an extruder and transferring the doses onto said molding means; and conditioning means for conditioning temperature of said doses during transfer thereof from said extruder to said molding means.

Abstract: Embodiments of the invention provide a method and apparatus for manufacturing dental aligners. The system includes a workpiece introduction system having at least one workpiece preparation chamber. The system further has a mold manipulation system, having a mold introduction chamber, where a series of different molds may be introduced one after the other; a mold preparation chamber; a workpiece operation chamber; and a mold manipulator to move the mold between the mold introduction chamber, the mold preparation chamber, and the workpiece operation chamber; and a workpiece manipulator to move the workpiece between the workpiece preparation chamber and the workpiece operation chamber.

Abstract: An apparatus for severing mold charges of molten plastic exiting an orifice along an orifice axis includes a motor system that provides a rotary output around an axis offset from the orifice axis. A blade arm is eccentrically coupled to the rotary output of the motor system for motion in a plane at an angle to the orifice axis, preferably perpendicular to the orifice axis. A knife blade is coupled to the blade arm and disposed to oscillate in a closed path, preferably an elliptical path, that intersects the orifice axis so that the knife blade engages and severs molten plastic exiting the orifice along the orifice axis. A control arm preferably is pivotally coupled to the blade arm and to a point that is fixed with respect to the orifice axis to control motion of the blade arm and the knife blade. The motor system preferably is mounted on a base, and has an output shaft that extends through the base and a hub coupled to the output shaft.

Abstract: A compression molding machine includes a support mounted for rotation around an axis and a plurality of angularly spaced molds disposed around the support. Each of the molds includes a first mold segment and a second mold segment. At least one of the mold segments is movable with respect to the other mold segment between a closed position for compression molding a plastic article, and an open position for removing a molded article from the mold and placing a mold charge into the mold. An apparatus is provided for placing mold charges into the molds in sequence.

Abstract: A machine for compression molding plastic closures includes a support mounted for rotation around an axis, and a plurality of compression molds on the support at angularly spaced positions around the axis. Each of the molds includes a male mold section and a female mold section, at least one of which is movable with respect to the other between a closed position to form a compression mold cavity and an open position spaced from each other. The male mold section includes a mold core and a stripper sleeve surrounding the mold core for movement both rotationally and axially of the mold core. A first screw drive couples the female mold section to the stripper sleeve for rotating the stripper sleeve around the mold core as the at least one mold section is moved between the closed and open positions. A second screw drive couples the stripper sleeve to the support to move the stripper sleeve axially over the mold core as the stripper sleeve is rotated around the core.

Abstract: Compression molding apparatus for molding plastic closures for containers includes a rotary turret having a vertical axis and supporting circumferentially spaced and axially moveable opposing plungers each carrying a compression mold member. Each mold member is attached to its corresponding plunger by a quick change locking coupler including a cylinder with circumferentially spaced holes supporting balls for radial movement. Each mold member has an axially projecting stud with an enlarged head portion projecting into the cylinder, and a cup-shaped piston surrounds the cylinder and has a recess for receiving the balls in a released position. A spring urges the piston to a locked position with the balls engaging the stud, and a housing is recessed within the plunger to support the piston for axial movement against the spring to a released position in response to pressurized fluid received within the housing through a passage within the housing and plunger.

Abstract: An apparatus for manufacturing hollow, plastics articles having internal undercuts, comprising at least one compression-molding unit, composed of an upper male mold part comprising a plug and of a lower female mold part aligned, with the male mold part, an actuation for actuating the mold parts between a spaced position, at which a dose of plastics is deposited in the female mold part, and an adjacent, compression molding position, a slideable tube, having an end portion with angularly distributed seats with oscillating elements articulated along radial planes, provided externally with recesses, a stem accommodated coaxially inside the tube, that actuates during the mold closure, the oscillating elements to form, with the tube end portion, the molding plug, and, during the mold opening a position in which to allow the extractor to remove articles from the plug.

Abstract: An assembly for the compression molding of articles made of plastic material, composed of a main male plug and a complementary male plug which comprise a stem, actuated by an actuation element with a spindle guided in a tubular tang provided with a molding head cooperating with the main male plug; a first spring, arranged on the spindle acting between a collar of the spindle and the tubular tang; a second spring, arranged on the spindle acting on the collar or on the end of the tang that lies opposite the molding head, to determine an inactive molding step of the complementary male plug, a compression step, and a reduced compression step.

Abstract: A method and device for the production of a closure cap having a first part (16, 17) and a second part (18), joined together by at least one thinner section (19). The device contains a female mould part (11) and a male mould part (12), which are moveable relative to one another, in order to enclose a mould cavity. After the closing of the mould cavity, an additional mould part (14) is moveable relative to the mould cavity. In order to reduce the volume thereof, until the plastics material fills the mould cavity completely. Consequently the invention ensures that when compression moulding in the mould cavity, the closure cap and in particular also the thinner section (19) are formed completely in the mould provided.

Abstract: A tamper indicating closure comprising a base wall and a peripheral skirt having an internal thread adapted to engage the threads of a container wherein a tamper indicating band is provided on the skirt by a plurality of circumferentially spaced bridges. The band includes portions adapted to engage an annular bead on the container. The bridges are formed by using a primary knife having an interrupted cutting edge to produce a circumferential score in the side wall of the closure leaving spaced connectors or bridges followed by using a secondary knife having a continuous cutting edge to provide a continuous external score line and an accurately dimensional radial thickness of the bridges. In a preferred method and apparatus, the closures engage the successive primary and secondary knives and are moved such that the closures roll relative to the knives.

Abstract: An improved mold tool for use in molding machines comprising a mold tool having a core and a stripper sleeve which move in vertical relation to one another for stripping a threaded molded part, the improvement comprising a race on one of said core or said stripper sleeve, a rotating stripper bushing which rotates within said stripper sleeve in relation to said race so that the vertical movement between said stripper sleeve and said core results in rotation of said rotating stripper bushing.

Abstract: An apparatus for molding and inserting in caps liners made of plastic material dispensed by an extruder, comprising: a dosage carousel; a molding carousel; an insertion carousel; a cap feeder for feeding the insertion carousel with caps, the carousels being rotatable about vertical axes and provided with seats for supporting multiple shuttles that are angularly equidistant concentrically to the rotation axes of the respective carousels, the dosage carousel having assemblies for taking in succession doses of plastic material from the extruder and depositing them onto the shuttles, the molding carousel having assemblies for molding in succession liners on the shuttles and the insertion carousel having assemblies for removing in succession the liners from the shuttles and inserting them in respective caps fed by the feeder; and a first, second and third star, for shuttle transferring at the respective carousels.

Abstract: A molded closure having an auxiliary thread for removal of an incomplete closure from a molding cavity, the molded closure including a helical auxiliary thread projecting inwardly from a cylindrical wall portion of the closure to provide engagement between the closure and the molding core, so that the closure may be threadably removed from the molding cavity by threadably disengaging the molding core from the molding cavity after an incomplete run of the fabrication process. A molding assembly with which the auxiliary thread may be formed in a molded closure is also provided.

Abstract: The mold comprises:

Abstract: Apparatus for compression molding plastic closures having a peripheral skirt with an internal thread includes a first mold assembly having a male mold core and a second mold assembly having a female mold cavity. At least one of the first and second mold assemblies is moved relative to the other to bring the male mold core into the female mold cavity for compression molding a closure, and then is moved to open the cavity such that the closure is retained on the male mold core. The male mold core is rotated relative to the first mold assembly to unthread the core from within the closure, and thereby strip the closure from the core, without stretching the closure skirt over the core or wiping the internal thread over the external surface of the mold core.

Abstract: An unscrewing mechanism for forming threaded components includes at least one rotatable elongate mold core having a threaded portion at one end for molding a threaded component, a stripper plate that is separable from a stationary plate and underlying a cavity plate in which is integrated a mating mold cavity, and a drive gear with a jack screw at one end and with gear teeth that mesh with mating gear teeth on the mold core for rotating the mold core such that a movement of the stripper plate away from the stationary plate for ejecting a formed threaded component is at the same rate as the unscrewing of the mold core. The jack screw is threaded such that a riser component pushes the stripper plate at the same rate that the mold core is unscrewing.

Abstract: The apparatus for shaping thermoplastic materials, in particular for producing moulded parts with a large height of the moulded part, comprises a suction-pressure bell and a lower part which can be locked to each other by a locking device. Resting on the lower part are a mould and a clamping frame, while the upper clamping frame can be securely clamped by working cylinders. In the locked state, the clamping frames are braced by a seal, which is arranged between the suction-pressure bell and the upper clamping frame. The seal extends over the entire circumference of the suction-pressure bell and is able to be pressed against the upper clamping frame by a pressure medium.

Abstract: An apparatus for manufacturing threaded caps comprises a plurality of compression molding assemblies which are arranged on a rotating carousel and comprise an upper male mold half and a lower female mold half. The male mold half comprises a tubular element, a sleeve guided coaxially to said tubular element, and a punch guided in the tubular element and having a helical slot for forming the thread of the cap. The punch enters the female mold half and produces, together with it, the cap through compression of a dose of plastic material deposited in the female mold half. After the spacing of the punch from the female mold half, the removal of the cap from the punch occurs by way of a removal device, which comprises a ring gear associated with the sleeve and provided with a collar in sliding contact on the punch, a rod which can slide axially in a seat of the carousel and supports a gear meshing with the ring gear and connected to a motor drive mechanism.