PNEUMATIC SCREW DRIVING MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a pneumatic screw driving machine having small energy loss by reducing the resistance with a cylinder inner wall in the vertical movement of a striking piston. SOLUTION: The striking piston 4 is formed so that the outer diameter is slightly smaller toward the tip, and an O-ring 31 is circumferentially provided on the minor diameter part 4a. The tip part 2a of the striking cylinder 2 is formed so that the inside diameter is small, and so that the O-ring 31 is pressed onto the inner wall 33 of the minor diameter part 2a of the striking cylinder 2 when the striking piston 4 is landed on a bumper 21 arranged on the bottom of the striking cylinder 2.