In the present invention, sealing tape is wrapped around the outer circumferential surface of an introduced mold, and a monomer solution is injected into a cavity formed therein, wherein the injection amount of the monomer solution can be precisely controlled by using a vision recognition system. According to a preferable embodiment, a monomer solution of a monomer solution tank is suctioned, in advance, into a syringe capable of adjusting a capacity corresponding to a mold; most of the monomer solution, which has been injected into the syringe, is firstly injected into the mold at a high injection flow rate or injection speed; while the residual amount of the monomer solution is secondly injected at a reduced injection flow rate or injection speed, it is finally confirmed, by using a vision recognition system, whether the monomer solution is filled in the mold; and then injection is finished.

An injection molding machine with an injection system and a clamping system. The injection system may include an injection module and an injection module receiver. The injection module is removably installed in the injection module receiver and includes a nozzle for introducing material into the mold. The injection module receiver may include a cooling system for cooling at least a portion of the nozzle. The cooling system may include a nozzle sheath fitted about the nozzle. The intermediate space between the nozzle sheath and the nozzle may define a coolant chamber through which liquid coolant may be moved to cool the nozzle. The nozzle and nozzle sheath may be configured to cooperatively define a coolant supply passage and a coolant return passage. The nozzle may include a nozzle tip that is fluted to provide a coolant flow path from the coolant supply passage to the coolant return passage.

A shut-off nozzle includes a nozzle body portion having an in-nozzle flow path formed therein, and a needle valve that is inserted into the nozzle body portion coaxially with the nozzle body portion and is configured to open and close an outlet of the in-nozzle flow path. A cylindrical portion is formed in the vicinity of a tip portion of the needle valve. A cylindrical hole portion is formed in the vicinity of a tip portion of the in-nozzle flow path, the cylindrical hole portion being a cylindrical hole. The cylindrical portion is configured to be fitted into the cylindrical hole portion in a case where the needle valve is driven in a forward direction.

The invention relates to a stopper for a sprue of a casting mould, said stopper having a through-passage for introducing casting material into the sprue of the casting mould and being designed such that it automatically closes the through-passage to prevent casting material from flowing out of the casting mould, and also to a method for filling a casting mould with casting material, having the steps of: inserting such a stopper into a sprue of a casting mould and introducing casting material into the through-passage.

An injection molding system including a nozzle member (18) or a valve pin (80) having a tip end (21) wherein the nozzle member (18) or valve pin (80) is adapted to be controllably rotatable around a longitudinal rotation axis (A) to enable an exit aperture (20) of the nozzle or the tip end of the pin to interface with a cavity entrance aperture (30) to controllably vary or adjust size (SP1, SP2) of the cross sectional area (CA) of a gate aperture (50) according to degree of rotation (R) of the nozzle or valve pin around the rotation axis (A).

An injection molding apparatus has an injection cylinder in fluid communication with the mold, wherein movement of a piston within the cylinder injects a selected quantity of resin into the mold. A plasticizing unit includes a flighted screw rotating in a heated containment barrel for plasticizing resin the plasticizing unit in selective fluid communication with the injection cylinder for supplying the injection cylinder with plasticized resin. A conduit connects the plasticizing unit to the injection cylinder to communicate resin from the plasticizing unit to the injection cylinder.

A shut-off nozzle includes a nozzle body portion having an in-nozzle flow path formed therein, and a needle valve that is inserted into the nozzle body portion coaxially with the nozzle body portion and is configured to open and close an outlet of the in-nozzle flow path. A cylindrical portion is formed in the vicinity of a tip portion of the needle valve. A cylindrical hole portion is formed in the vicinity of a tip portion of the in-nozzle flow path, the cylindrical hole portion being a cylindrical hole. The cylindrical portion is configured to be fitted into the cylindrical hole portion in a case where the needle valve is driven in a forward direction.