Patent ID: 8636081

Claim:
A rotary hammer adapted to impart axial impacts to a tool bit, the rotary hammer comprising: a motor; a spindle coupled to the motor for receiving torque from the motor; a piston at least partially received within the spindle for reciprocation therein; a striker received within the spindle for reciprocation in response to reciprocation of the piston; an anvil received within the spindle and positioned between the striker and the tool bit, the anvil imparting axial impacts to the tool bit in response to reciprocation of the striker; a retainer received within the spindle for selectively securing the striker in an idle position in which it is inhibited from reciprocating within the spindle; and an O-ring positioned between the retainer and the spindle, and disposed around an outer peripheral surface of the anvil; wherein the O-ring is compressible in response to the striker assuming the idle position, wherein an inner diameter of the O-ring is reduced in response to being compressed, and wherein the compressed O-ring imparts a frictional force on the outer peripheral surface of the anvil to decelerate the anvil.