PURPOSE: To absorb shrinkage quantity accompanying solidification of molten metal by intermingling auxiliary bars easily deformed to radius direction in bar assembly composed of multi pieces of bars having rectangular cross section.
CONSTITUTION: As this apparatus has structure intermingling the auxiliary bars 8 easily deformed to radius direction compared with the bar 2 in the bar assembly 3 composed of multi pieces of the bars 2 having rectangular cross section, in the case of manufacturing a pattern having recessed pattern surface 3a by transferring projecting pattern surface 3a of the bar assembly 3, as shrinkage quantity accompanying the solidification of molten metal can be absorbed with deformation of the auxiliary bars 8, the development of crack and sticking of the bars 2, etc., as casting defect can be prevented. Further, by pulling out of the auxiliary bars 8, the bar assembly 8 is suddenly collapsed and pattern shake-out work can be easily executed.
YAMAGUCHI NOBUYUKI
IMAMURA HIROSHI
TODOROKI MASAAKI
