PREPARATION OF CYLINDER HEAD COVER BY REACTION INJECTION MOLDING

摘要

PURPOSE:To obtain a cylinder head cover with only a little warpage and deviation of dimensional accuracy whose thermal and mechanical strength are garanteed even at high temp. atmosphere, by controlling stepwisely the descending amt. of a slide in accordance with the shrinking amt. of a reactive molding material during hardening. CONSTITUTION:A mold 15 is heated and controlled at a required temp. about 160 deg.C by means of a heating device and a poured reactive molding materials 18 reacts, gels, cures to a required shape. As the reactive molding materials 18 successively shrinks with reaction under heating, a pressing cylinder 13 descends stepwisely every required time in accordance with the shrinking amt. during hardening to lower a top force 16 stepwisely every minute amt. and to control the press in accordance with the viscosity of the reactive material 18 by inputting into a specified program controlling device not to excessively press.