MUFFLER FOR PNEUMATIC ROCK DRILL

摘要

One aspect of the invention concerns a pneumatic rock drill (10) having a cylinder (18), a least one exhaust opening (30) from the cylinder through which air is exhausted and a muffler (42) which extends around the cylinder and over the exhaust opening. The muffler has a muffler casing (44) which surrounds the cylinder and includes casing parts (46, 48) assembled together around the cylinder. The4 muffler casing defines a muffler space (70) extending around the cylinder with the exhaust opening venting into an upper part of the muffler space towards its rear end. There is a series of spaced apart exhaust ports (80) venting downwardly from a front end of the muffler space through the muffler casing. There is also a baffle structure (72) located in the upper part of the muffler space between the exhaust opening and the exhaust ports. This structure includes spaced apart, perforated baffle plates (76) through which air venting into the muffler space through the exhaust opening must pass en route to the exhaust ports. Another aspect of the invention concerns the muffler itself.