Patent ID: 7934923
Filing Date: 2011-05-03
Classification: B29C

Abstract:
1. A screw disposed within a heating cylinder such that the screw can rotate and can advance and retreat, a rear end of the screw being connected to a drive apparatus, the screw comprising: a screw head; a reverse-flow prevention apparatus; and a plasticizing member disposed rearward of the reverse-flow prevention apparatus, wherein the plasticizing member comprises a screw body, a flight projectingly formed on an outer circumferential surface of the screw body, and a pressure member formed to extend over a predetermined distance from a front end of the screw body and to be located adjacent to the reverse-flow prevention apparatus, wherein the pressure member comprises a flat outer circumferential surface comprising a diameter equal to or greater than a diameter of the screw body, wherein the flat outer circumferential surface comprises an outer circumferential surface of an inclined portion formed to be integral with the screw body and an outer circumferential surface of a large diameter portion formed to be integral with the inclined portion, and wherein, when the axial length of the large diameter portion is represented by L and the outer diameter of the flight is represented by D, the ratio L/D falls within the following range: