Patent ID: 7314315

Claim:
An improvement in a metal cutting machine having a reduction gearbox assembly containing, in a cast iron gearbox, a first and second thrust bearing each having an inner ring attached to a motor-driven high speed shaft and each having an outer ring retained in a respective region of the cast iron gearbox, and having a motor coupling with a driving coupling member attached to a motor shaft and a driven coupling member attached to the high speed shaft, the improvement comprising: a first annular adaptor machined from metal and configured with a cylindrical sleeve having a machined cylindrical opening press-fitted onto the outer ring of the first thrust bearing, and having a machined outer cylindrical surface slide-fitted into a first cylindrical opening machined in the gearbox; a second annular adaptor machined from metal and configured with a cylindrical sleeve having a machined cylindrical opening press-fitted onto the outer ring of the second thrust bearing, and having a machined outer cylindrical surface slide-fitted into a second cylindrical opening machined in the gearbox; each of the two coupling members being configured with a coaxial compressible sleeve having an inside diameter dimensioned to fit onto the associated shaft in a slide-fit manner in absence of externally-applied compression: a compression ring surrounding each compressible sleeve, the ring and the sleeve being configured to fit together at a conical interface made and arranged to compress the compressible sleeve to a condition of secure attachment to the associated shaft, in response to displacement of the compression ring relative to the selected corresponding member in a designated axial direction; and in each of the coupling members, a set of machine screws arranged in a polar array traversing the member and engaging a corresponding set of threaded holes provided in the compression ring, such that, for deployment, tightening the set of machine screws draws the compression ring in the designated direction and thus, by inclined plane action at the conical interface, compresses the compressible sleeve to the condition of secure attachment to the associated shaft; wherein, for service purposes either coupling member may be released and easily removed from the associated shaft by loosening the set of machine screws and moving the compressible ring in a direction to decompress the compressible sleeve.