Patent ID: 7549491
Filing Date: 2009-06-23
Classification: B23B,B23K

Abstract:
1. A hard material bit for a rotary-percussion tool ( 2 ), comprising at least one cutting edge ( 3 ); a bottom surface ( 6 ) located opposite the at least one cutting edge ( 3 ); at least one attachment surface ( 8 ) extending transverse to the bottom surface ( 6 ) and forming a piecewise extending first chamfer ( 9 a ); and at least one free surface ( 10 ) extending likewise transverse to the bottom surface ( 6 ) and forming a piecewise extending second chamfer ( 9 b ) having a width greater than a width of the first chamfer ( 9 a ), wherein the first chamfer ( 9 a ) and the second chamfer ( 9 b ) are arranged next to the bottom surface ( 6 ).