Abstract: A balloon control ring to control ballooning phenomenon taking place in yarn being spun out from spinner or twister, wherein the inner circumferential surface thereof is formed with grooves provided therealong, yarn contacting surfaces located respectively above and below said grooves and bank portions so located as to divide adjacent ones of said grooves.

Abstract: A bobbin doffing and donning method and apparatus are disclosed, wherein a stop is selectively projected into a path, along which an engaging member, mounted on a suitable portion of a power transmission mechanism structurally associating a doffing bar with a piston and cylinder assembly for tilting the doffing bar, is moved by the piston and cylinder assembly, to allow the engaging member to pressure contact with the stop thereby stopping the doffing bar at an intermediately tilted condition under which the doffing bar can operate on bobbins temporarily placed on a refuge support positioned between a succession of spindles and a bobbin conveyor both arranged along the side of a spinning machine.In order to release the doffing bar from the intermediately inclined condition, fluid is supplied into the piston and cylinder assembly so as to temporarily move the engaging member in a direction in which it disengages from the stop and thereafter the stop is moved out of the path of the engaging member.