A method includes a first molding process and a second molding process performed repeatedly. The first molding process includes injecting resin into a first pair of molds, in which a first pair of divided pieces is formed and which is fitted together without an inner mold, to couple the first pair of divided pieces to form a first hollow article at an injection station. The second molding process includes (i) injecting resin into a third pair of molds, which is fitted together with one inner mold interposed therebetween, to mold a third pair of divided pieces at the injection station, (ii) taking out the first hollow article from the first pair of molds at a removing station, and (iii) removing another inner mold from a second pair of molds while leaving a second pair of divided pieces between the second pair of molds at the setup station.

The invention concerns an injection overmoulding device comprising at least one indexed rotary turret on which cooled moulds are installed, each mould comprising a plurality of cavities, and at least five stationary stations arranged around said turret, including at least a first station, a second station and a third station that are used, respectively, for carrying out the operations of positioning the inserts in the cavities of the mould, injecting plastic material into the cavities of the mould, and demoulding the at least partially cooled objects. The device comprises, for each mould, at least separate injection means. The invention also concerns a method implemented by the device.

A method includes a first molding process and a second molding process performed repeatedly. The first molding process includes injecting resin into a first pair of molds, in which a first pair of divided pieces is formed and which is fitted together without an inner mold, to couple the first pair of divided pieces to form a first hollow article at an injection station. The second molding process includes (i) injecting resin into a third pair of molds, which is fitted together with one inner mold interposed therebetween, to mold a third pair of divided pieces at the injection station, (ii) taking out the first hollow article from the first pair of molds at a removing station, and (iii) removing another inner mold from a second pair of molds while leaving a second pair of divided pieces between the second pair of molds at the setup station.

In order to achieve lower costs in a molding apparatus using a mold by reducing mold cleaning steps following releasing of the product from the mold and shortening the molding cycle, the apparatus is equipped with a plurality of fixed molds and movable molds which are heated to the temperature necessary to harden a molding material and come together by means of clamping to form a cavity, and a non-heated cold runner which supplies the molding material from an injection device to the interior of the cavity via a gate opened in the movable mold, the fixed molds and movable molds being movable between an injection stage where the injection device and cold runner (32) are present and an opening stage near the injection stage.