Worm gear brake selection
Worm gear brake selection
(OP)
Hello,
How common is it to damage a worm gear with back driven torque load due to braking from a motor?
I have a slew drive with a 75:2 ratio and a planetary gearbox with an electric motor. The motor has a brake on the back. I need the brake for emergency stops, but when I use the maximum brake torque to calculate the effective torque on the output shaft using the gear ratio & back drive efficiency, I am exceeding the maximum output torque on the slew gear(including service factor). Our motor supplier has already specified their lowest torque brake.
Sorry, I am new to worm gear drives. Is the concern regarding gear damage due to brake torque valid?
How common is it to damage a worm gear with back driven torque load due to braking from a motor?
I have a slew drive with a 75:2 ratio and a planetary gearbox with an electric motor. The motor has a brake on the back. I need the brake for emergency stops, but when I use the maximum brake torque to calculate the effective torque on the output shaft using the gear ratio & back drive efficiency, I am exceeding the maximum output torque on the slew gear(including service factor). Our motor supplier has already specified their lowest torque brake.
Sorry, I am new to worm gear drives. Is the concern regarding gear damage due to brake torque valid?





RE: Worm gear brake selection
While your 37.5:1 worm gear stage is not capable of back-driving, you still need to ensure that the thrust bearing used for the worm is capable of handling the inertia forces created by an E-stop condition.
RE: Worm gear brake selection
Yes, the worm gear and the gearbox on the motor is back-drivable. We have efficiencies of 65-70% on the worm gear. It has a ratio of 37.5:1 with 2 starts. I am expecting that the thrust bearing will be included in the maximum output torque rating for the slew gear itself, but I will check.
The back driving capability is required in this application so we can manually reposition the driven load during power off failure condition (after manually releasing the brakes).
RE: Worm gear brake selection
I doubt that it's common, only because no one would want a system that breaks the gearbox when the power is removed.