Gerry45
Mechanical
- Sep 16, 2002
- 53
I have a large and heavy piece of industrial equipment that is rotated into different angular positions via a 2m dia gear ring. The gear-ring is driven by the output pinions of six electric motor powered gear units positioned around it.
The system works well under power because the six gear-units share the load evenly. However, when not driving, shock loads from the equipment tend to travel back to the drive-units. Unfortunately because the ratios of the drives make them non-reversible, differences in drive-unit backlash together with differences between ring-gear and drive-pinion backlash seem to concentrate the loads on some (or perhaps one!) of the drive units. This can result in breakage of teeth in the ring-gear, drive pinion or drive-units.
Solutions to even out the 'reverse' loads could include the fitting of slipping clutches etc. However, because such things could result in reduced controlability of the system I'm reluctant to go this direction. So Im aiming to try to make the best of the existing set-up, if possible.
It may be possible to ask the drive-unit maker to match the units for backlash. But that still leaves me with some variability due to the radial tooth-runout of the ring-gear relative to the positions of the six drive units.
Does any one know if there is a special (but robust) geartooth profile available that would be much less sensitive to the radial runout of the ring-gear and therefore provide more even load sharing on the six drive-pinions ?
I hope I have explained this clearly, if not please let me know.
Gerry
The system works well under power because the six gear-units share the load evenly. However, when not driving, shock loads from the equipment tend to travel back to the drive-units. Unfortunately because the ratios of the drives make them non-reversible, differences in drive-unit backlash together with differences between ring-gear and drive-pinion backlash seem to concentrate the loads on some (or perhaps one!) of the drive units. This can result in breakage of teeth in the ring-gear, drive pinion or drive-units.
Solutions to even out the 'reverse' loads could include the fitting of slipping clutches etc. However, because such things could result in reduced controlability of the system I'm reluctant to go this direction. So Im aiming to try to make the best of the existing set-up, if possible.
It may be possible to ask the drive-unit maker to match the units for backlash. But that still leaves me with some variability due to the radial tooth-runout of the ring-gear relative to the positions of the six drive units.
Does any one know if there is a special (but robust) geartooth profile available that would be much less sensitive to the radial runout of the ring-gear and therefore provide more even load sharing on the six drive-pinions ?
I hope I have explained this clearly, if not please let me know.
Gerry
