US Patent:
20170342831, Nov 30, 2017
Inventors:
- Latrobe PA, US
Brandon J. Kenno - Windber PA, US
Nicholas J. Paros - Johnstown PA, US
International Classification:
E21C 35/19
E21C 25/10
E21C 35/183
E01C 23/088
E21C 35/18
Abstract:
A rotatable cutting tool () includes a cutting tool body () having an axial forward end () and an axial rearward end (). A bolster () at least partially received in a head portion () and includes a convex-shaped head portion () with a socket (), a collar portion () and a tapered shank portion (). The socket () is formed with a substantially planar side wall (), a bottom wall (), and a radius blend (). A hard tip or cutting insert () is at least partially received in the socket () of the bolster () and includes a convex-shaped conical head portion (), a collar portion () and an axially-rearward portion () that generally conforms to the geometry of the socket () of the bolster (). Between about sixty percent (60%) and about ninety percent (90%) of the cutting insert () is received in the socket () of the bolster (), thereby reducing forces and stresses transmitted to the cutting tool () during a machining operation.