Gear Ratios and Efficiency
Gear Ratios and Efficiency
(OP)
Assuming that we have a gear ratio g < 1 from the driving to the driven gear in terms of the number of teeth. Say g = 0.01 and assume the gear train efficiency e is 0.8.
To me, this means that the effective output torque, Tout, will be reduced so that
Tout = e x Tin/gr .
Also, if one uses energy conservation
[Tout x Omega_out] / [Tin x Omega_in] = e,
this also tells me that the effective speed at the shaft will reduce.
This is where I get confused. Motors have a inversely proportional torque-speed relationship. Doesn't this say that if the effective torque reduces, then the effective speed increases?
TIA
Klaus
To me, this means that the effective output torque, Tout, will be reduced so that
Tout = e x Tin/gr .
Also, if one uses energy conservation
[Tout x Omega_out] / [Tin x Omega_in] = e,
this also tells me that the effective speed at the shaft will reduce.
This is where I get confused. Motors have a inversely proportional torque-speed relationship. Doesn't this say that if the effective torque reduces, then the effective speed increases?
TIA
Klaus





RE: Gear Ratios and Efficiency
i.e
Tout = e x Tin/gr and
Vout = gr*Vin
=> Tout x Vout = e x Tin x Vin
Is this valid?
TIA
Klaus
RE: Gear Ratios and Efficiency
with a gear.
Cheers
Greg Locock
RE: Gear Ratios and Efficiency
RE: Gear Ratios and Efficiency
TIA
RE: Gear Ratios and Efficiency
Cheers
Greg Locock
RE: Gear Ratios and Efficiency
Klaus
RE: Gear Ratios and Efficiency
Tout * Omegaout = (Tin - Tfriction)* Omegain
If your goal is to apply a specific output torque, then you need to use more input power than you would expect if you didn't take friction (and other losses) into account.
Steven Fahey, CET
"Simplicate, and add more lightness" - Bill Stout