Patent ID: 7303718

Claim:
An injection molding apparatus having a pair of dies, a bush, and a nozzle, the bush having a receiving portion formed in a semi-spherically recessed surface, the bush having an inner resin flow path through which resin is supplied to a cavity formed by the pair of dies, the nozzle having a tip portion formed as a semi-spherically protruded surface, the semi-spherically protruded surface of the tip portion of the nozzle including a resin injection hole and being press-contacted to the semi-spherically recessed surface of the receiving portion of the bush, molten resin being injected into the cavity through the nozzle and the bush, wherein a center portion of the semi-spherically recessed surface of the receiving portion of the bush protrudes in a direction towards the nozzle as a protrusion portion, and wherein the protrusion portion includes a semi-spherically recessed surface whose radius of curvature is the same as the radius of curvature of the semi-spherically protruded surface of the tip portion of the nozzle so that the inner resin flow path surface-contacts to only the periphery of the hole end of the resin injection hole.