Patent ID: 7681690

Claim:
A noise-abatement device for a pneumatic tool, comprising: a housing having a first end wall, a second end wall, and a body extending from the first end wall to the second end wall, the housing defining an expansion chamber therein; at least one tube located at least partially within the expansion chamber, the tube having a first end, an opposing second end, a non-perforated portion proximate the second end, a perforated portion proximate the first end, and an outlet defined in the second end of the at least one tube, wherein the first end of the at least one tube is sealed thereby preventing fluid from entering or exiting the first end of the at least one tube, and wherein the perforated portion includes a first set of perforations a first distance from the first end wall and at least a second set of perforations a second distance from the first end wall, wherein the second distance differs from the first distance; and a port outlet in fluid communication with the expansion chamber, wherein the port outlet and the outlet are positioned closer to the second end wall of the housing than the first end wall.