PURPOSE: To keep the relative distance between a work unit and a yarn feeder to a constant level and to carry out the transfer work in optimum and stable state by performing the capturing work based on the output signal of a distance sensor attached to a yarn feeder transfer work unit at the tip end of a robot arm.

CONSTITUTION: In the automatic transfer of a yarn feeder on a pallet to a creel with a robot 10 in a weaving preparation process, a yarn feeder catching chuck 22 is placed on a bracket 21 of a yarn feeder transfer work unit 20 attached to the tip end of a robot arm 13 and a distance sensor 31 is placed in front of the chuck 22. The work unit 20 approaches the yarn feeder on a pallet by the motion of the robot arm 13. When the distance between the unit and the feeder reaches a prescribed level, the distance sensor 31 outputs a signal, the catching chuck 22 catches the yarn feeder based on the signal and the yarn feeder is attached to a prescribed position of a creel by the motion of the robot arm 13.