| 摘要 |
An innovative injection moulding machine (11 ) for plastic materials, comprising a mobile mould-bearing platen (14) and a fixed mould-bearing platen (16) bearing respectively a first mobile half-mould (12a) and a second fixed half-mould (12b) of a mould (12); an actuating unit (20) including an actuating rod (17) to move the mobile mould-bearing platen (14) towards the fixed mould-bearing platen (16) in such a way as to close the two half-moulds (12a, 12b) together; a closing unit (26, 30) operatively connected to the mobile mould-bearing platen (14) in order to close it, in the closed position (P2) corresponding to the contact between the two half-moulds (12a, 12b), against the fixed mould-bearing platen (16); and blocking means (241, 261 ) associated with the closing unit (26, 30) to block the mobile mould-bearing platen (14) when it is in the closed position (P2), wherein the closing unit (26) comprises a hydraulic force amplifier (30) which is adapted for receiving, from a piston (38) defined at one end (17a) of the actuating rod (17), a given input force (Fo) and applying in response, upon the mobile mould-bearing platen (14) in the closed position (P2), a given closing force (FS) that is amplified with respect to the input force (Fo). The fixed structure (50) of the moulding machine comprises two tie bars (73, 74) which extend between two sides (71, 72) in the longitudinal direction parallel to the stroke (C) of the mobile mould-bearing platen (14) and which are suitable for receiving and contrasting totally the amplified closing force (FS) produced by the hydraulic amplifier (30). The moulding machine (11 ) also comprises an injecting unit (120) provided with a special reflux device (141 ) which enables the molten plastic material (PL) to flow backwards during the final stage of injecting and compacting of the plastic material injected into the mould (12). |
