Patent ID: 8603429
Filing Date: 2013-12-10
Classification: B65H,D01F

Abstract:
1. A production method for a carbon fiber thread by continuously subjecting a carbon fiber thread precursor having a jointed portion connecting respective ends of two carbon fiber thread precursors to heat treatment, the production method comprising steps of: detecting the jointed portion by a difference in thickness between the jointed portion and other portions of the carbon fiber thread precursor; subjecting the carbon fiber thread precursor, including the joined portion, to a heat treatment to obtain a carbon fiber thread; acquiring positional information of a position where the jointed portion is located between a position where the jointed portion has been detected and a position where the carbon fiber thread is wound up on a winder; determining a calculated time for the jointed portion to arrive at the winder based on the positional information; cutting the carbon fiber thread before and after the jointed portion based on the calculated time; and winding separately a carbon fiber thread including the jointed portion and a carbon fiber thread not including the jointed portion, both being made by the cutting, the carbon fiber thread including the jointed portion and the carbon fiber thread not including the jointed portion being separately wound up around different winding bobbins such as a jointed portion-winding bobbin and a product-winding bobbin.