PURPOSE: To dispense with the remodeling of a bobbin holder and the alteration of package form and specifications, by installing a dividing groove, for dividing one bobbin into plural pieces in the longitudinal direction, in a circumferential direction of the bobbin.

CONSTITUTION: After giving an oily agent to plural yarn filaments Y1WY4 spun out of spinnerets 1 and 1' with an oil giver 2, they are rolled on each of two crests 71, 72 and 7'1, 7'2 on two bobbins 6 and 6' installed in a winder 5 by way of receiving rollers 3 and 4. These bobbins 6 and 6' are provided with dividing grooves 8 and 8' in the circumferential direction so as to be halved in the longitudinal direction, and furthermore provided with thread cutter grooves 91, 92 and 9'1, 9'2 which performs thread cutting at the time of bobbin selection and simultaneously clamps a yarn end. Thus, winding and package are performable with the bobbin of the same length in the past, dispensing with the remodeling of a bobbin holder and the alteration of package form and specifications, thus equipment cost at the time of carrying out multi-crest winding is reducible.