Patent ID: 8936454
Filing Date: 2015-01-20
Classification: B29B,B29C

Abstract:
1. A resin extrusion die configured to extrude a molten resin comprising a thermoplastic resin composition, supplied from an extrusion machine into a strand, the resin extrusion die comprising: a cap comprising a discharge nozzle through which the molten resin is extruded; a cover comprising a gas outlet that forms a gap around a tip of the discharge nozzle, wherein the cover covers at least part of the cap, forming a space between the cap and the gas outlet; a gas supply port configured to supply a gas to the space; an adjusting mechanism configured to adjust a relative positional relationship between the cover and the cap; and a vibration unit that vibrates the cap, wherein both the gas outlet and an orifice of the discharge nozzle are circular, and a center of the gas outlet is arranged at a position shifted from a center of the orifice, wherein the gas outlet forms, around the tip of the discharge nozzle, the gap whose ratio of maximum width to minimum width, dmax/dmin, is in a range from 1.05 to 2.0, thereby changing the gas flowing out of the gap to a turbulent flow, and wherein the vibration unit is configured to dynamically change the gap around the tip of the discharge nozzle by vibrating the cap within a range of amplitude: 0.005 to 0.2 mm, and vibration velocity: 0.3 to 5 mm/sec.