| 摘要 |
Method for injection-moulding plastic articles by means of a fully positive mould, the mould being charged under pressure with a warm, curable material which, after the mould has been charged, is kept under a dwell pressure for a predetermined time. During said charging operation, part of the material is stored in an additional chamber which communicates with the mould and in which the material remains under a predetermined pressure after supply of material during injection has been discontinued, in order to ensure that a dwell pressure will act on the material while curing takes place. During the injection phase, the material present in the additional chamber from the previous injection phase is forced out of said chamber into the mould, and during charging of the fully positive mould the flow rate introduced thereinto, preferably a constant flow rate, of warm curable material is composed of the flow rate of the material to be newly introduced and that of material to be introduced into or discharged from the additional chamber, thereby allowing the material to be introduced into the additional chamber to maintain the dwell pressure, thus doing away with a complicated valve system.
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