Air motor driven tool exhaust silencer - has expansion chamber around motor with discharge into further chamber formed in tool hood

摘要

A pneumatic tool (1) has an air motor (2) within its casing to drive a shaft (4) which carries a grinding wheel (5) or other attachment on its end. The motor is surrounded by an air expansion chamber (6). The air exhausted from the motor passes through this chamber into a second chamber (7) which is formed from a sheet steel casing (9, 10) and surrounds the end of the tool. The second chamber has air discharge openings (8) in its outer wall (10) and can be lined internally. The expansion of the air reduces the noise of the discharge and the protection afforded by the chambers enables the body of the tool to be made lighter and therefore cheaper.