Page 295 - Gear Technology Solutions

20.4 Basis of Shaft Deviation Tolerances

In many cases of industrial gearbox design with bevel gears, the Gleason
guideline with tolerances for the bevel gear shaft positioning tolerance can be
very helpful. The tolerances which are compiled for average gearsets might
not be the optimal numbers for the specific gearset a manufacturer is develop-
ing. Nevertheless, the Gleason tolerance guideline may be very useful at a
stage when only a few details of a new transmission are finalized.

Figure 5: Contact movement in profile and lead direction

In order to have a solid foundation for the shaft positioning tolerances, the im-
pact onto the backlash as well as the contact pattern movement have been
considered during the development of the tolerance tables. The contact
movement definition is shown in Figure 5. Contact movements in lead direc-
tion had been limited to 1.0mm and profile movements were limited to 0.3mm
for medium size bevel gearsets with module 4mm.

Figure 6: Change of backlash due to gear cone change G

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