Abstract: An apparatus for high frequency molding plastic material using a mold made of a conventional material for applying this technique, e.g. a silicone elastomer or like material. The mold is kept locked shut while the shaped plastic material is cooling by the effect of a pressure reduction set up inside the mold after the high frequency electric field has been applied.

Abstract: A method for high frequency molding by injecting a liquid plastic material under pressure into a mold, while simultaneously venting the inside cavity of the mold, optionally by applying to suction. In order to overmold and/or mold onto a prisoner a part in the form of a closed loop, a sealing insert (i) is disposed between the openings into the mold for its injection nozzle (17) and its venting nozzle (18). The shape of the insert corresponds to the profile of the mold, and the insert is made of a material having the same nature as the injected plastic material, such that the insert melts and is welded to the molded or overmolded part when the high frequency electric field is applied by means of an appropriate generator. The injection and the venting nozzle are controlled by respective double action actuator devices fitted with pistons and piston rods made of a material which does not exhibit dielectric loss, and forming a removable unit assembly.

Abstract: An apparatus for high frequency molding by injecting a liquid plastic material under pressure into a mold, while simultaneously venting the inside cavity of the mold, optionally by applying to suction. In order to overmold and/or mold onto a prisoner a part in the form of a closed loop, a sealing insert (i) is disposed between the openings into the mold for its injection nozzle (17) and its venting nozzle (18). The shape of the insert corresponds to the profile of the mold, and the insert is made of a material having the same nature as the injected plastic material, such that the insert melts and is welded to the molded or overmolded part when the high frequency electric field is applied by means of an appropriate generator. The injection and the venting nozzle are controlled by respective double action actuator devices fitted with pistons and piston rods made of a material which does not exhibit dielectric loss, and forming a removable unit assembly.