Muffler for pneumatic power tool and pneumatic power tool incorporating the same

A pneumatic power tool, comprising:

• a housing having an inlet passage and an exhaust passage;
• and
• a muffler assembly configured for insertion into the exhausted passage of the housing, the muffler assembly including:
• a tube member defining an interior volume and including:
• an upper segment defining a first diameter, the upper segment including a closed upper end to inhibit fluid communication with the interior volume therethrough, a lower end, a first portion defining a plurality of vents to enable fluid communication with the interior volume therethrough, and a second portion defining a continuous surface to inhibit fluid communication with the interior volume therethrough;
• and
• a lower segment defining a second diameter greater than the first diameter, the lower segment including an upper end in fluid communication with the lower end of the upper segment, a lower end, a first portion defining a plurality of vents to enable fluid communication with the interior volume therethrough, and a second portion defining a continuous surface to inhibit fluid communication with the interior volume therethrough;
• a filter panel configured to wrap around both the upper and lower segments of the tube member;
• a receptacle disposed at the lower end of the lower segment of the tube member in fluid communication therewith;
• and
• a diffuser panel disposed within the receptacle.