Carousel-type apparatus for manufacturing caps made of plastics by compression molding

An apparatus for manufacturing threaded caps by way of compression molding assemblies arranged on a structure of a carousel, which rotates about a vertical central axis thereof, the molding assemblies comprising each an upper male mold half and a lower female mold half aligned with each other along a further vertical axis parallel to said rotation central axis of the carousel;

• and a seat;
• said male mold half including:
• a tubular element fixed to said structure coaxially to said her parallel axis;
• a sleeve guided coaxially to said tubular element and having a lower portion;
• a stem provided at an end thereof with a punch having a helical slot for forming the cap threads, said punch being movably guided in said tubular element;
• elastic means for exerting a raising action to move said punch up to a raised stroke limit position;
• actuation means for hydraulic actuation of said female mold half from a lowered position for receiving a dose of plastic material sufficient to form a cap, to a raised position in which said punch enters said female mold half to provide, with the female mold half, a cap molding chamber and compression of said dose of plastic material so as to form a cap, and subsequent descent of the female mold half in order to allow spacing of the female mold half from said punch and removal of said cap from said punch;
• and removal means for removing said cap from said punch, wherein said removal means comprise:
• a ring gear associated with said lower portion of said sleeve;
• a collar provided in sliding contact on said punch at said lower portion of said sleeve and adapted to engage said threaded cap;
• a rod connected for axial motion transmission to said sleeve and which is axially slidable in said seat of said structure parallel to said rotation central axis of said carousel;
• a gear which is supported on said rod so as to mesh with said ring gear;
• motor drive means drivingly connected with said gear;
• a stationary cam provided at the structure of the carousel to command, in synchronized operation with said motor drive means, actuation of said rod for axial motion thereof, corresponding movement of said collar in engagement with said threaded cap and respective rotation of the collar for unscrewing said cap from said punch, axial drawing of said punch against the raising action of said elastic means;
• and an axially stationary cam which controls gradual rise of said punch as unscrewing of the cap advances.

An apparatus for manufacturing threaded caps by way of compression molding assemblies arranged on a structure of a carousel, which rotates about a vertical central axis thereof, the molding assemblies comprising each an upper male mold half and a lower female mold half aligned with each other along a further vertical axis parallel to said rotation central axis of the carousel;

• and a seat;
• said male mold half including a tubular element fixed to said structure coaxially to said further parallel axis;
• a sleeve guided coaxially to said tubular element and having a lower portion;
• a stem provided at an end thereof with a punch having a helical slot for forming the cap threads, said punch being movably guided in said tubular element;
• elastic means for exerting a raising action to move said punch up to a raised stroke limit position;
• actuation means for hydraulic actuation of said female mold half from a lowered position for receiving a dose of plastic material sufficient to form a cap, to a raised position in which said punch enters said female mold half to provide, with the female mold half, a cap molding chamber and compression of said dose of plastic material so as to form a cap, and subsequent descent of the female mold half in order to allow spacing of the female mold half from said punch and removal of said cap from said punch;
• and removal means for removing said cap from said punch, wherein said removal means comprise:
• a ring gear associated with said lower portion of said sleeve;
• a collar provided in sliding contact on said punch at said lower portion of said sleeve and adapted to engage said threaded cap;
• a rod connected for axial motion transmission to said sleeve and which is axially slidable in said seat of said structure parallel to said rotation central axis of said carousel;
• a gear which is supported on said rod so as to mesh with said ring gear;
• motor drive means drivingly connected with said gear and comprising a gear train including a first gear meshing with said gear even during the axial movements of said rod and a second gear meshing with said first gear;
• cam means provided at the structure of the carousel to command, in synchronized operation with said motor drive means and only at a rotation angle of the carousel in which unscrewing of the cap is requested, actuation of said rod for axial motion thereof, corresponding movement of said collar in engagement with said threaded cap and respective rotation of the collar for unscrewing said cap from said punch, axial drawing of said punch against the raising action of said elastic means and controlled gradual rise of said punch as unscrewing of the cap advances.