PURPOSE: To automatically wind a weft on a length-measuring pulley by transferring the weft from a gripper into a guide cover surrounding the length-measuring pulley through a guide tube, and subsequently guiding the weft from a discharging tube into the opening of warps with a weft-feeding means.

CONSTITUTION: In the weft delivery of a fluid jet type loom, a weft intermittently delivered from a bobbin by the action of a gripper is passed through a guide tube 3 by the flow force of a fluid from a fluid-supplying tube 37, guided into a guide cover 35 connected to the guide tube 31, surrounding the peripheral surface of a length-measuring pulley 17 and extended to a port 17b for pulling out the weft to automatically wind up the weft on the length-measuring pulley 17. Subsequently, the prescribed length of the weft wound on the length- measuring pulley 17 is fed into a picking main nozzle with the force of the fluid from the fluid-charging tube 37 through a discharging tube 36 whose one end is connected to the weft-pulling port 17b and whose other end is extended to a place near to the main nozzle.