If trying to achieve a 1:4 gear ratio, will a planetary gear system help reduce the loss of torque? Or is it essentially no different than the loss of torque when using a large drive gear to rotate a small driven gear?


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Apart from frictional losses, which should be fairly low for a 1:4 ratio, the torque/speed ratio is inescapable ie if you increase the angular speed by a factor of 4 the torque must be reduced by a factor of 4.

Power is torque x angular velocity so if this was not the case you would get more power out than you put in, which as we know is not possible.

Planetary gears can be used to produce quite high ratios in a compact package and also have the ability to change ratios by locking different combinations of input/output/carrier eg in automatic transmissions but their fundamental principal of operation is the same as any other type of gear or indeed any type of mechanical advantage.


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