Patent ID: 7748975

Claim:
A molding die for molding a hollow molding article, comprising: a pin plate having an inflow port for molding material; a tubular bushing forming a molding path continued from the inflow port and having an entrance portion; an outlet of the die positioned in the extending direction of the molding path and opposite to the entrance portion; a conical pin provided perpendicularly to the pin plate and disposed inside the molding path, the conical pin including a distal end, a bottom surface, and a continuously varying outer diameter from the distal end to the bottom surface; a gap, that is continuous in a longitudinal direction, being provided between an inner wall surface of the molding path and an outer surface of the conical pin, an inner circumference of the entrance portion and the outer surface of the conical pin forming a standard annular gap which is smaller than an exit gap defined between an inner circumference of the outlet and the outer surface of the conical pin; and an adjusting device for adjusting a width of the standard annular gap.