A yarn length measuring device for a yarn winding device

摘要

The yarn length measuring device includes: a means (73) that detects a yarn layer peripheral surface movement distance ΔPLs of a yarn layer formed by the winding yarn (4) around a winding tube (6) ; a means (74) that detects a traverse movement distance ΔTLs of the yarn; and a winding length computing means (75) that inputs the yarn layer peripheral surface movement distance ΔPLs, and the traverse movement distance ΔTLs, detected by the traverse movement distance computing means (74), calculates a winding length of the yarn (4) wound around the winding bobbin (6, 7) at each time (Ts) from the ΔTLs and the ΔPLs that have been input, and determines a winding length (YL) of the yarn (4) wound around the winding bobbin (6, 7) by summing up the winding lengths Δ YL calculated at each predetermined time (Ts).