Patent ID: 7309195

Claim:
A shank for a rotary and/or percussive tool, comprising: at least two, axially spaced, guide regions ( 1 a , 1 b ); at least one radially projecting entrain strip ( 2 ) arranged between the at least two guide regions ( 1 a , 1 b ); and at least one locking groove ( 3 ) arranged between the at least two guide regions ( 1 a , 1 b ), the at least one locking groove ( 3 ) being axially closed at opposite ends thereof and adapted to receive at least one radially displaceable and axially displaceable, within predetermined limits, locking member ( 4 ) of a chuck, wherein the two guide regions ( 1 a , 1 b ) have identical diameters equal to a guide dimension (F), and an axial region (A) of the at least one locking groove ( 3 ) has a cross-sectional width (B) that includes a radial extent of the entrain strip ( 2 ), and a thickness (D) measured in a direction transverse to the width measurement direction, and wherein the guide dimension (F) is greater than the thickness (D) but smaller than the width (B), and wherein a maximum aperture angle (α) of a bottom surface of the at least one locking groove ( 3 ), which is defined by a cross-section of the axial region (A) of the at least one locking groove ( 3 ), amounts to 180°.