PROBLEM TO BE SOLVED: To provide replacement means for facilitating replacement of a plastic cutting line.SOLUTION: The present invention relates to a line-winding spool for grass-cutting heads, comprising a central body provided with a central axis of rotation, the central body having a circumferential side area on which there is defined the annular area where the cutting line is wound, the spool having at least one channel crossing the central body transversally, provided with two openings on opposite portions of the side area for the insertion of the cutting line, the at least one channel being between two opposite first segments starting from the openings toward the inside of the central body and the first segment, the at least one channel having a curved connection segment having a concave shape with the concavity upward, the central body defining, in the concavity, a cavity, of which bottom is at a lower axial height than the axial height of the openings, characterized in that the curved connection segment has a lower surface that is continuous along all its extension so as to be substantially closed downward with respect to the outer environment, to allow a single passage of the cutting line from one opening toward the opposite opening to be configured without the cutting line exiting from the central body.SELECTED DRAWING: Figure 1BCOPYRIGHT: (C)2016,JPO&INPIT【課題】樹脂切断刃の簡単つな交換手段の提供。【解決手段】ライン巻取スプールであって、中心回転軸線が設けられた中心本体を備え、中心本体が切断ラインが巻かれる環状領域が画定された外周側部領域を有し、スプールが中心本体を横切る少なくとも一つの通路を有し、切断ラインの挿入用に側部領域の対向する部分に二つの開口が設けられ、一つの通路が、開口から中心本体の内側に向かう二つの対向する第一セグメントと、第一セグメント間にあり、上向きの凹面を有する凹形状を持った湾曲連結セグメントとを有し、中心本体が凹面において、底部を有するキャビティを画定し、底部が開口の軸方向高さより低い軸方向高さにあり、湾曲連結セグメントが外部環境に対して、実質的に下方に向かって閉じられるように、その全長に沿って連続する下面を有し、切断ラインが中心本体から出ることなく、一方の開口から対向する開口に向かう単一の切断ライン通路を構成する。【選択図】図1B
