To remove fly waste from a tension device provided to a yarn winding device.
A feed opening 36 and a feed passage 37 are provided in a casing outer side plate part 34, and a ventilation truck 38 and trunk air outlets 39a and 39b are formed in a front plate part 31 formed by joining a surface member 318 and a rear face member 31R. A gate tension device 40 pinches the yarn Y between a swinging tip 43 of a movable gate part 41 and a yarn engaging part 46 of a fixed gate part 45 to give tension. Cleaning air is sent into the feed opening 36 provided in the casing outer side plate part 34 and fed into the ventilation truck 38 in the front plate part 3I through the f ed passage 37 so as to make the cleaning air spout from the trunk air outlets 39a and 39b. The fly waste can be thereby removed outside the tension device 4 without badly influencing on an operator. Since a swinging shaft 42 of the movable gate part 41 in the gate tension device 40 is placed on the near side of the swinging tip 43, the fly waste is prevented from clinging and adhering to the swinging shaft 42, and flow of the cleaning air is smoothened.