worm gear

[dennis45]

Please excuse my ignorance but I have a question regarding gears and torque. When using a gearbox with a 20:1 gear reduction do I get a 20:1 torque advantage. And if so, is this also the case with a 20:1 worm gear? It seems to me that the two would be different. Any input would be appreciated. Thanks. Dennis

 

[insideman]

Yes. you get a twenty to one mechanical advantage, less the losses involved.

 

[dennis45]

So am I correct in stating that a worm gears torque output has nothing to do with the diameter of the bull gear?

 

[plawrence]

I'll go out on a limb here and say that torque does depend on the diameter of the bull gear inasmuch as the diameter and pitch determine the number of teeth which determines the ratio.

 

[diamondjim]

Since torque is only dependant on
the radius of the worm times the tangential
force. It does not matter what the gear
is. The tangential loads on both are the
same and the torques are based on their
individual pitch radii.

 

[sacem1]

The diameter of the worm wheel does not have anything to the rate that it will multiply the torque, except for the loses in efficiency, but it does have in HOW MUCH TORQUE you can multiply.

That is a 2" 40 teeth worm gear mated to a single thread worm will multiply the torque supplied in the input shaft by a factor of 40, and it will work probably well up to a 2 HP input at 1750 rpm, but if you multiply the torque input of the motor by reducing the input speed, lets say via a pulley/belt arrangement then probably if you try to use the full output torque what you would get is a stripped tooth for the worm wheel. The same applies if you raise the input torque with a bigger motor.