| Gear theory is reexamined and we nd optimal shapes for gears. As optimality criteria, we allow: (1) minimal frictional losses (highest eeciency) assuming linear law of friction or (2) uniform maximum stress (it will wear out slowly and last the longest) assuming Hertzian contacts or (3) uniform maximal temperature, assuming we are in a high power limit in which all heat is removed by the lubr...

This paper covers the development, design and simulation of an automatic real time control system applied in mechanical system of recovery of spur gears. using modern techniques of automatic welding. This automatic system permits to recover the initial geometric contour of the wheel by performing automatic welding runs across each tooth, keeping the mechanical properties intact. The thermal mod...