| 摘要 |
<p>956,687. Feeding moulding material to moulds. ETABLISSEMENTS ALCA, FRANCE. June 29, 1961 [June 30, 1960], No. 23488/61. Heading B5A. A process for extruding small measured quantities of thermoplastic material comprises passing granular thermoplastic material into a plasticizing chamber 51 applying a limited pressure via a piston 59 to pass the plasticized material through a non-return valve 62 into another chamber 63 to which a second greater pressure is applied via a piston 70 to extrude a predetermined quantity of material via a spring-loaded valve 65 through a nozzle and finally cooling the material. Means to supply predetermined quantities of the granules to a hopper 57 connected to the plasticizing chamber 51 comprises a reservoir 24 of the granules above a movable shutter 22, the opening of which allows the descent of the granules into a chamber 19 which is bounded by a movable plate 18, its position in the chamber 19 being controlled by the forward movement of the piston 59. At the end of said forward movement the shutter 22 closes and a shaft 14 rotates so that the plate 18 is lowered and the predetermined quantity of granules falls into the hopper 57 connected to the plasticizing chamber 51.</p> |
