The rotary transfer mechanism transferring rotary force from motor (1) to tool (20) comprises a pinion (10) mounted rotatable about an intermediate shaft (14) and able to slide in the axial direction of same. A first socket (12) is fixed on the intermediate shaft and a first coupling mechanism (11) selectively brings the pinion to engage with the first socket to transfer the rotary force to the tool and then disengages pinion to stop force transfer. A hammer mechanism transferring the hammer force to the tool comprises a second socket (6) set around the intermediate shaft. This second socket cannot rotate about the shaft but is able to slide in axial direction of same. A motion transfer member (4) rotates about the intermediate shaft to convert the rotary force of the motor into the hammer force. A second coupling mechanism (5) brings the motion transfer member in and out of engagement with the second socket to start and stop transfer of hammer force .
