Abstract: An apparatus and method for the production of bi-material hollow bodies by injection overmolding. The apparatus includes: n base molding cavities or groups of base molding cavities inserted between n+1 overmolding cavities or groups of overmolding cavities or vice versa; and 2n cores or groups of cores which are fixed to a core holder plate mounted such that it can move in a transverse direction on a base plate that is actuated to move in a longitudinal direction in order alternately to insert each core into one of the base molding cavities, so as to mold a first layer, and into one of the overmolding cavities, so as to overmold a second layer. The apparatus also includes an ejecting device for ejecting the finished bi-material hollow bodies and a valve for alternately distributing the molding material to one or the other of the outer cavities.

Abstract: The two-layered preform includes a tubular body having a mouth providing a neck at a first end thereof and a closed bottom at an opposite second end. At least part of the tubular body is formed by a first layer (P1) made of a primary molding material and a second layer (P2) made of an overmolding material. The first layer (P1) is an inner layer made of a primary molding material providing a barrier effect against light by absorption, and the second layer (P2) is an outer layer made of an overmolding material providing a barrier effect against light by reflection. The neck is formed with the overmolding material of the second layer (P2) not coated by the primary molding material of the first layer (P2).

Abstract: The two-layered preform includes a tubular body having a mouth providing a neck at a first end thereof and a closed bottom at an opposite second end. At least part of the tubular body is formed by a first layer (P1) made of a primary molding material and a second layer (P2) made of an overmolding material. The first layer (P1) is an inner layer made of a primary molding material providing a barrier effect against light by absorption, and the second layer (P2) is an outer layer made of an overmolding material providing a barrier effect against light by reflection. The neck is formed with the overmolding material of the second layer (P2) not coated by the primary molding material of the first layer (P2).

Abstract: An apparatus and method for the production of bi-material hollow bodies by injection overmolding. The apparatus includes: n base molding cavities or groups of base molding cavities inserted between n+1 overmolding cavities or groups of overmolding cavities or vice versa; and 2n cores or groups of cores which are fixed to a core holder plate mounted such that it can move in a transverse direction on a base plate that is actuated to move in a longitudinal direction in order alternately to insert each core into one of the base molding cavities, so as to mold a first layer, and into one of the overmolding cavities, so as to overmold a second layer. The apparatus also includes an ejecting device for ejecting the finished bi-material hollow bodies and a valve for alternately distributing the molding material to one or the other of the outer cavities.

Abstract: The mold includes a first molding cavity connected to a first hot channel for supplying a primary molding material, a second overmolding cavity connected to a second hot channel for supplying an overmolding material; and a core configured to be first introduced in the first cavity for a molding operation of a first layer, and to then be introduced, with the first layer thereon, in the second cavity for an overmolding operation of a second layer. At least one supporting member is arranged to support the core with respect to the first cavity during the entire molding operation of the first layer. An opening left in the first layer by the supporting member is filled and/or covered by the second layer.

Abstract: An apparatus and method for the production of bi-material hollow bodies by injection overmolding is disclosed. The apparatus includes: n base molding cavities or groups of base molding cavities inserted between n+1 overmolding cavities or groups of overmolding cavities or vice versa; and 2n cores or groups of cores which are fixed to a core holder plate that is mounted such that it can move in a transverse direction on a base plate that is actuated to move in a longitudinal direction in order alternately to insert each core into one of the base molding cavities, to mold a first layer, and into one of the overmolding cavities, to overmold a second layer. The apparatus also includes an ejector for ejecting the finished bi-material hollow bodies and a valve for alternately distributing the molding material to one or the other of the outer cavities.

Abstract: An extruder assembly for an injecting moulding machine in which the screw point pin has a small diameter that can float and is self-centering. The pin has two support points or flats. The screw point and pin are used as a check valve in front of the piston screw of an injection molding machine for plastic materials. As a result of the small diameter of the pin the total output of plastified material is not diminished and there are no head losses. The screw point can be adapted to any models of injection molding machine, and its technical advantages give it high performance both in the field of what are known as “technical” molded parts and in the field of high-speed packaging.