Patent ID: 6015248
Filing Date: 2000-01-18
Classification: B23B,B27G,G01N,Y10S,Y10T

Abstract:
A wood coring drill bit comprising:a hollow tube having an internal bore and an exterior with three equally spaced bodies of substantially uniform width extending in a helical manner from a cutting end of said drill bit, said bodies defining three equally spaced flutes between the edges of adjacent bodies, each body comprisinga land upstanding from a relief at the leading edge of the body, a respective cutting face having an included angle which is within the range of 106.degree. to 131.degree. and associated lip being formed at the end of each body at said cutting end, said lip having a lip clearance angle that is approximately 6.degree..+-..degree.1;wherein the lands on the bodies extend for an axial distance of about 65 mm.+-.5 mm from said cutting end and the internal bore of the hollow tube is tapered outwardly from or adjacent the cutting end.