Patent Number: 7,712,647

Title: Driving machine

Abstract: A driving machine includes a cylinder, a piston fitted into the cylinder in a reciprocatingly movable manner, a driver connected to the piston, a bumper provided in the bottom portion of the cylinder, a housing, a return air chamber, a fastening member feed piston movable backward or forward by supplying compressed air within the return air chamber from an air chamber passage hole 9 through air passages and to a fastening member feed cylinder or discharging such compressed air from the fastening member feed cylinder, a return spring for energizing the fastening member feed piston, and a feed pawl mounted on the leading end of the fastening member feed piston. In the driving machine, between the return air chamber and the fastening member feed cylinder, a filter portion is provided having a projection shape and small holes.

Inventors: Tanji; Isamu (Ibaraki, JP)

Assignee: Hitachi Koki Co., Ltd.

International Classification: B25C 1/04 (20060101); B25C 5/13 (20060101)

Expiration Date: 5/11/12018