PURPOSE: To provide a simple device for adjusting the twist of a spacer at the time of dropping coated fiber ribbons into the slits of this spacer.

CONSTITUTION: While the spacer 1 formed with n-pieces of the spiral wire- shaped slots S1, S1,... of a pitch(p) is rotated in the spiral direction of the spiral wires, the spacer is fed at a feed speed V=pN and n-pieces of the coated fiber ribbons 2 are discretely inserted and dropped from the respective tangential directions of the slits S1, S2,... in the outer peripheral part of the spacer 1. A dropping guide cylinder 3 which is formed to a hollow tubular form, has a front end serving as a driven pawl 13 to be fitted into the respective slots S1, etc., and is turnable around the axis 32 of rotation of its base part is used for the purpose of discrete dropping of these fiber ribbons.