Patent ID: 8042621

Claim:
An impact mechanism ( 12 ) for an impact wrench ( 1 ), said impact mechanism ( 12 ) comprising: an anvil ( 8 ) rotatable about a rotation axis (R) and provided with a middle portion ( 13 ), at least one abutment portion ( 14 ) radially protruding therefrom, which forms at least one abutment surface ( 15 ); and a hammer ( 4 ) rotatable about the rotation axis (R) comprising a rear portion ( 22 ) suitable to provide a connection with a drive shaft ( 11 ) of a reduction mechanism ( 3 ) and a front portion ( 24 ) forming at least one impact relief ( 26 ) forming at least one impact surface ( 16 ), the front portion ( 24 ) comprising a base plate ( 25 ) having a shape of an annular disc and connecting diametrically opposing areas of the front portion ( 24 ) thereby stiffening the front portion ( 24 ) in a plane perpendicular to the rotation axis (R), and the front portion ( 24 ) with the impact relief ( 26 ) and the rear portion ( 22 ) being formed integrally, wherein the base plate ( 25 ) extends radially inside the hammer ( 4 ) and is disposed radially inward of said at least one impact relief ( 26 ) and forms an internal abutment surface for a spring ( 20 ) of a hammer engaging mechanism, said internal abutment surface for said spring ( 20 ) being formed inside the hammer ( 4 ), and wherein a seat for said spring ( 20 ) is arranged radially outward of a tubular member, radially inward of the drive shaft ( 11 ) and radially inward of said impact relief ( 26 ), wherein the hammer ( 4 ) is suitable to give rotational pulses to the anvil ( 8 ) by the impact surface ( 16 ) hitting the abutment surface ( 15 ), wherein the anvil ( 8 ) comprises a first connection area ( 17 ) connecting the abutment portion ( 14 ) to the middle portion ( 13 ), said first connection area ( 17 ) at least partially extending within the axial extension of the abutment surface ( 15 ) and the middle portion ( 13 ), wherein the anvil ( 8 ) comprises a reinforcement rib ( 18 ) being axially arranged out of the abutment surface ( 15 ), which connects the abutment portion ( 14 ) to the middle portion ( 13 ) of the anvil ( 8 ), thereby forming a second connection area.