PURPOSE: To shorten the operation cycle of spinning frames by reducing or removing the time while the spinning frame stops, after the bobbins become full, even in the case that the full bobbins are not yet completely carried out.

CONSTITUTION: A transfer unit TU is operated after doffing and a peg tray 6 is allowed to move at the spindle pitch in the arrow direction based on the request signal of the full bobbins to taken out the full bobbins and bring in the empty bobbins until the next doffing starts. Usually, all of the full bobbins are carried out from a conveyer 4, then a first sensor 15 is turned off and the tray transfer unit(TU) stops operation. In the case that the carrying-out of the full bobbins are delayed, for example, by some trouble, if the number of the bobbins brought in does not reach the prescribed number of the bobbins on the spindle rows on the time when the full bobbins stop in the machine frame 1, the tray transfer unit is stopped its operation, when the number of the counter reaches the prescribed one. A second sensor 16 is set in order to confirm that a prescribed number of empty bobbins are fed.