| 摘要 |
<p>The present invention relates to a ground drilling hammer and a sleeve thereof, and more specifically, to a ground drilling hammer and sleeve which comprises, a cylindrical casing, a back head in which external compressed air flows, a guide and a sleeve which distribute the compressed air into the top and the bottom of a piston, wherein the piston is moved up and down by the compressed air, a chuck combined at the bottom of a casing, and a button bit which digs the ground by the hitting force of the piston. In addition, the ground drilling hammer and the sleeve thereof allow smooth up-and-down motion of the piston, because there is little space to form an oppressed air chamber on one side of the piston, and considerably improves the durability of the equipment by reinforcing the physical strength of the sleeve and the piston at the same time.</p> |
