Learning Forum

[Rajveer7]

Hello Everyone,

I am trying to do the analysis of gear pair together for my 2 stage reduction gearbox which we want to use in SAE BAJA. I am getting satisfactory results in single gear analysis, but when I am doing pair analysis Equi. Stress is very low around 100-105 Mpa. I don't know where or which part I am doing wrong. Please do let me know whats the right way to do a gear pair analysis. Herewith I am uploading its STEP file

[peteroznewman]

Hello,

Please read these three discussions and reply if you still have questions.

Discussion 1

Discussion 2

Discussion 3

Regards,
Peter

[Rajveer7]

Thanks for the help, but my main question differs a bit. I Cant understand at which portion should I apply force (Point load, moment or etc.). whenever I am validating single gear (Pinion or gear), Stress is coming as per my hand calculations which are done by Shigley's Machine design (reference). But when I am doing an analysis of a pair of gears, either I am applying wrong boundary conditions or some other error is prevailing. Please do let me know whats the wrong part, SOme of the important data I am listing out:- 

Engine torque (Max):- 20N.m

Max RPM:- 3800

Shaft radius: -30mm

Max Power:- 10.15 Kw

Driving is pinion Gear

[peteroznewman]

In your model above, a contact force is developed on the pair of teeth in contact as a result of the moment you have applied to the pinion. Does this explain where the force comes from?

You list the Engine torque as 20 N.m but you have a Moment of 250 N.m, is that because this pinion is not on the engine output shaft, but after a gearbox?

[Rajveer7]

Yeah sorry, that was my bad! , it was my error in giving inputs and yeah there is a CVT attached to engine output shaft and another end is connected to the gearbox,

But for gearbox analysis, we need to consider its max RPM that is around 3800 at rated torque 20N.m. I don't know how to do a gear pair analysis. 

How to give contact force at teeth in contact? I thought that pinion is driving so I applied moment on pinion face and fixed the gear, am I doing it wrong? If yes then what's the correct way of doing the analysis? 

@peteroznewman

 

 

 

and I have uploaded result video in this link when you'll watch it you 'll come to know my pinion gear is just sliding over main gear. (If you can please help me with that )

https://drive.google.com/file/d/1G26_gP3n0TjYWWErWI4V4Dl2YukEksuD/view?usp=sharing

 

Thank You