gearbox efficiency

[hi_im_sean]

i read somewhere that the gearboxes for the drill motors(i mean the helical ones that go on the drive shaft) only have 47% efficiency. now i dont know if that is true but if it is will that slow down the robot to matter.

[EDIT]** enough to matter[/EDIT]

[Dick Linn]

I would expect the efficiency of a right-angle helical gear arrangement to be at least as good or better than a worm gear. While worm gears can be as bad as 35% efficiency (with a high reduction ratio, like 70:1), I understand that they are typically 65-80. I would anticipate these gears being somewhere around 80-85% efficient. A good parallel shaft helical arrangement can be as good as 98% efficient.

I would be much more concerned with the mounting of the motor, the dimensions of the spacer tubing that holds the two gears in alignment inside the gearbox and lubrication. Even the best gearbox can arrangement can be made inefficient!

Want to see what "gear-heads" talk about? Check out http://www.qtcgears.com/Ask/index.asp If you want some general info about gearing, check out this primer from Georgia Tech: http://www.srl.gatech.edu/education/...og/gearbas.htm