Image Number 17 for United States Patent #7425293.
Method for forming articles of synthetic material by compression moulding, comprising the following operative stages: inserting a first measured quantity of synthetic material in the plastic state into the cavity of a mould comprising a punch with which it defines a first forming chamber for said measured quantity; pressing said measured quantity to obtain a first portion of the article; opening the mould and inserting a second measured quantity into said cavity; closing the mould by repositioning the punch relative to said cavity to define a second forming chamber; pressing said second measured quantity and again opening the mould, then extracting said article from the punch.The method is implemented by a plant comprising a plurality of forming units (3), and at least one device (5', 5'') for feeding in succession at least two measured quantities (100, 201) of synthetic material in the plastic state to each of said forming units (3, 43, 81), each of said forming units comprising an upper half-mould provided with at least one punch (110, 46) and a lower half-mould comprising at least one die (29, 70, 90, 91) provided with a cavity matching said at least one punch (110, 46), means being provided to align said at least one die with said at least one punch in succession and to drive said die along the alignment axis, and means which collaborate with said at least one punch and said at least one die in such a manner as to define at least two different forming chambers.
|
