Vertical mill gearbox

A vertical mill gearbox, comprising:

• a casing;
• a drive shaft mounted in the casing for rotation about a substantially horizontal first rotation axis, said drive shaft having one end provided with a bevel-gear pinion;
• an intermediate shaft configured as a hollow shaft and mounted in the casing for rotation about an substantially vertical second rotation axis, said intermediate shaft having a lower region provided with a bevel gear in meshing engagement with the bevel-gear pinion of the drive shaft;
• a torsion shaft received in the intermediate shaft in fixed rotative engagement with the intermediate shaft, said torsion shaft configured to extend beyond the intermediate shaft to define a projecting section;
• a sun gear rotatably driven via the intermediate shaft and fixed to the projecting section of the torsion shaft;
• a planet carrier mounted in the casing for rotation about the second rotation axis;
• an internal gear fixedly retained on the casing and having an internal tooth system;
• and
• a planet gear rotatably supported by the planet carrier, said planet gear meshing with the sun gear and with the internal tooth system of the internal gear.