Abstract: A mold is provided for forming caps for closing containers by compression molding doses of plastic material, where a bottom wall of the cap, or at least one portion of the bottom wall is very thin. The mold includes two half-molds axially movable towards each other which assume an end closed position without a dose. A tubular element is slidable around the second half-mold and partially defines the cavity. The tubular element contacts an axial abutment of the first half-mold at one side and an axial end stop of the second half-mold at the other side to prevent hard contact between the half-molds.

Abstract: An apparatus comprises a moulding unit having a punch and a mould cavity movable along a path between an open position in which said punch and said mould cavity are distanced apart from each other to receive a dose of plastics therebetween, and a closed position in which said punch and said mould cavity interact to form an item by pressing said dose, said punch being kept not above said cavity along said path.

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: An apparatus for compression molding plastic articles, comprising at least one molding unit composed of an upper punch and a lower mold provided with a cavity for molding the articles, the punch and mold being aligned with each other and movable between a spaced position and a closer positions, feeders for feeding doses of plastic material to be molded, comprising at least one removal element for removing, in succession, individual doses from an extruder and depositing a removed dose in the molding cavity of the mold when it is spaced from the respective punch, supporting elements for temporarily supporting said dose above the molding cavity, associated with the mold, and actuators for actuating the supporting elements so as to release a dose into the cavity before compression start.

Abstract: A mold for manufacturing plastic items, composed of a female mold half and of a male mold half which are mutually aligned along a vertical axis, the male mold half being composed of a sleeve and a plug which is guided inside the sleeve and is movable with respect thereto; the female mold half comprises a base plate, a bush which is guided on the base plate and forms, together with the base plate, a cavity for receiving a dose of plastic material to be molded, the bush being provided with an abutment which acts as a locator for the sleeve during molding, the bush being movable with respect to the base plate in contrast with elastic return means which allow the plug to enter said cavity.

Abstract: Apparatus for manufacturing items made of plastics, particularly screw caps, by pressure molding, which includes a carousel on which molding units are arranged, each molding unit comprising an upper plunger against which a half-mold is hydraulically pushed. The half-mold defines a cavity inside which a dose of plastics has been introduced. Separation elements for extracting the cap after its manufacture are associated with the plunger.