公开(公告)号：US10988862B2

公开(公告)日：2021-04-27

申请号：US16074685

申请日：2017-01-31

Applicant: TOHO TENAX CO., LTD.

Inventor： Fumio Akiyama ,  Tadayuki Aoyama ,  Ichiro Kitano

IPC: D01F9/21 ,  D02J1/08 ,  D01F9/22 ,  D01F9/32 ,  B65H69/06 ,  D01D10/02

Abstract: A carbon fiber manufacturing method includes joining first and second target fiber bundles with a joining fiber bundle, and carbonizing the joined bundles by feeding them through one or more carbonization furnaces. The joining includes forming an overlap between a first end of the joining fiber bundle and a second end of the first target fiber bundle and jetting a fluid to the overlap to form a first entangled portion, and forming an overlap between a second end of the joining fiber bundle and a first end of the second target fiber bundle and jetting a fluid to the overlap to form a second entangled portion. When the first and second entangled portions each have two or more entangling points with a tensile strength not less than 400 N, the relationship defined by the inequality is satisfied: 40>{L2/(L2−A)}×(S+13), where L2 is a length (mm) of an elongation section inside a first carbonization furnace upstream in a feeding direction of the fiber bundles, A is a maximum distance (mm) between an entangling point in the first entangled portion and an entangling point in the second entangled portion, and S is an elongation (%) of the joined fiber bundles fed through the carbonization furnace.