Single-helical gearwheel for turbine auxiliary drive - has annular unloading groove witn periphery radiused at bottom to avoid crack propagation

摘要

The single-helical gearwheel (S) is esp. for use with turbines, to drive auxiliaries such as tachometers, oil pumps, overspeed governors etc. from the main shaft. It has one or more annular unloading grooves (9) cut in its periphery (b). This is pref. approximately 1 mm. deeper than the teeth roots, at least 5 mm wide at the bottom and radiused, to avoid crack formation or propagation.