Procedure and equipment for mfg. moulding closed plastic impeller, etc. - comprises preparing moulding cavity, filling moulding by casting and solidifying material allowing impeller to be produced as unitary structure

摘要

A procedure for mfg. a closed impeller comprises: (a) preparing a moulding cavity (21) defined by at least a number of cores (19, 20); (b) filling the cavity by casting molten materials; and (c) subsequently solidifying the material to mfr. a piece (40). The first part of a core (19) is extracted when in contact with a surface of the piece. The second part of a core (20) is extracted when a reciprocal approaches between the second part of a core and the surface of the core. Also claimed are: (i) equipment for mfg. a closed impeller.; and (ii) a core for mfg. the above. (i) has two opposed matrices (4, 11) between which the cores (19, 20) can be inserted so as to define a moulding cavity (21). Each core has first and second parts which can be separated by sliding one with respect to the other.