Patent ID: 7252158

Claim:
A tool ( 20 ) for impacting a workpiece ( 22 ), comprising; a casing ( 42 ) defining a chamber ( 48 ), an impactor device ( 24 , 54 ) slidable within said chamber ( 48 ) for impacting the workpiece ( 22 ), an exhaust valve ( 100 ) for selectively introducing and releasing pressurized fluid into and out from said chamber ( 48 ) to slide said impactor device ( 24 , 54 ) in said chamber ( 48 ), and a pilot valve ( 200 ) in fluid communication with said exhaust valve ( 100 ) for controlling said exhaust valve ( 100 ), said pilot valve ( 200 ) including a sealing member ( 214 ) having an initial position for sealing off fluid communication between said exhaust valve ( 100 ) and atmosphere and a biasing device ( 216 ) for biasing said sealing member ( 214 ) from said initial position to an actuation position to instantaneously provide fluid communication between said exhaust valve ( 100 ) and atmosphere to actuate said tool ( 20 ).