PURPOSE: To simplify a feeding device, and let it securely actuate by fixing a vertically long guide to an hammering tool, and providing a mouth piece guided to be slidable lengthwise in the vertically/long guide.

CONSTITUTION: In a process of moving a mouth piece 4 against force of a spring 5, a screw 7 advances into a recess 4a in the mouth piece 5, and it is aligned with a screw driver 2 till the screw 7 reaches an screwing position. Next, a control pin 17 moves into a horizontal recessed part downwardly opened in an edge member 18, and the mouth piece 4 also moves backward against force of the spring 5 till a tip of the screw driver 2 reaches a head part 7a of the screw 7. As the mouth piece 4 further slides in this direction, a clutch between the screw driver 2 and a drive part of an hammering tool 1 is charged, and the screw driver 2 starts rotating. The screw driver 2 is engaged with a cross-groove at a screw head part 7a to let the screw 7 straight, and the screw 7 folds and returns a tab through a recessed part in a supply strip member 11 to move into the mouth piece 4 to be screwed.