Patent ID: 9056434
Filing Date: 2015-06-16
Classification: B29D,G02B

Abstract:
1. A method for extrusion-molding a loose tube using an extrusion-molding apparatus that includes an extrusion head that includes a tip and a die concentrically arranged within the extrusion head and extrudes a tube between the tip and the die, and a needle that feeds at least one optical fiber and filler to be filled around the optical fiber into the tube being extrusion-molded, the method comprising: passing the optical fiber through a bundling hole to bundle the optical fiber at a center of the tube, the bundling hole being formed at a center of a bundling member provided within the needle and having an inner diameter smaller than an inner diameter of the tube; and passing the filler through a flow path to fill the filler around the optical fiber, the flow path being provided between the bundling hole and an inner circumferential surface of the needle, wherein a guide member is provided upstream of the bundling member along a feeding direction of the filler in the extrusion-molding apparatus, a guide hole being formed at a center of the guide member, being larger than the bundling hole, and having an inner diameter smaller than a length twice as a distance from the center of the bundling member to the flow path, and the optical fiber is introduced into the bundling hole with being guided by the guide hole.