Simple gear pair: efficiency and output torque
Simple gear pair: efficiency and output torque
(OP)

Hi. I have a question about output torque and efficiency of a simple gear pair as shown on the picture. So, I have a pinion and a gear. I give an input torque Tp in the clockwise direction. Therefore, the pinion will rotate with ωp angular velocity in clockwise and the gear ωg in counter-clockwise. Then, I apply a load Tl in the opposite direction of the gear motion (clockwise direction). The gear is still rotating in the counter-clockwise. I neglect the friction between the gear mesh, but I consider the bearing friction both in pinion cp*ωp and gear cg*ωg. The moments of inertia of the pinion and the gear are Ip and Ig, respectively. My question is what the output torque To is because I want to find the efficiency of this gear pair. Thank you very much.





RE: Simple gear pair: efficiency and output torque
obviously.
However by ignoring the friction at the teeth you are ignoring the main source of inefficiency in a typical gear pair, so your calculation of efficiency is probably useless.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Simple gear pair: efficiency and output torque
If To = Tl, I would not get a correct efficiency η.
η = Po/Pi = To ωg/(Tp ωp) = Tl ωg/(Tp ωp)
we know that rg ωg = rp ωp and ωg/ωp = rp/rg, so
η = Tl rp/(Tp rg)
In this equation, we can see that Tl/Tp has to be rg/rp in order to have η = 1. If I don't have Tl/Tp close to rg/rp, the efficiency could be much less than 1, for example 0.2, which doesn't make sense.
RE: Simple gear pair: efficiency and output torque
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Simple gear pair: efficiency and output torque
RE: Simple gear pair: efficiency and output torque
Incomprehensible.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Simple gear pair: efficiency and output torque
RE: Simple gear pair: efficiency and output torque
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?
RE: Simple gear pair: efficiency and output torque
RE: Simple gear pair: efficiency and output torque
It's weird to refer to it as efficiency because there is no loss of energy due to the mesh.
RE: Simple gear pair: efficiency and output torque
RE: Simple gear pair: efficiency and output torque
je suis charlie
RE: Simple gear pair: efficiency and output torque
RE: Simple gear pair: efficiency and output torque
The torque applied to the gear by the pinion is unaffected by load.