To find KHBeta 1

[LMGK]

Hi all, Its necessary for my research to find KHBeta as a function of profile correction value (µm, crowning correction) and variable torque, so KHBeta-i = f(Ti,Kj), though i have some doubts what r all the actual parameters will play role in it. The aim is to find KHBeta in planetary gear of meshes sun/planet and annulus/planet. Hope someone put light on it. thanks,

lmgk

 

[diamondjim]

I think you will need to create a
program to mimic the shaper cutter used
to cut the internal gear teeth.
I assume the pinions are cut with a hob.
This may be easier to calculate.
You basically are creating a K chart
to show the profile deviations cut
by a topping hob or modified shaper?
Not certain how you take in the effects
of crowning.

 

[LMGK]

I just want to find the load distribution along the face width with variable torque. Virtually, each mesh has uneven load distribution along the width, may very small in planetary gears. Its possible to have the even load distr. by doing profile correction on the flank. For that one has know the parameters which are influenced like tooth mesh stiffness, Kv,b,.. I would to know the exact formula to find KHBeta as a function of variable torque and correction values(µm). thanks

 

[diamondjim]

You certainly make it sound simple.
Are you going to accept load sharing
along the line of action? I would
assume your are going to assume
equal sharing of the load on the planets.
A spread sheet may be required using
small interval increments from the tip
to the lowest point of contact.
Are you assuming just an edge crown?
I would hope that an industrial program
exists and would be worth the money rather
than having to develop this yourself.

 

[paulliu]

A 3D elastic contact problem analysis should reveal
the relation between the KHBeta and the profile
modification.

 

[LMGK]

Thanks to all. yes we r looking the load sharing on the planets. we already developed profile correction program for constant torque. Right now lighting for variables torques. any web links for 3D elastic contact problem analysis ?.

 

[paulliu]

3D elastic problem analysis for gears can be carried
out using a good FEA code like ANSYS or ABAQUS. The
smaller codes like COSMOS or ALgor et. al. may also
do the job.
The web sites of FEA software companies like

http://www.ansys.com

http://www.abaqus.com

may mention how to solve these problems. Well,
I'm sure the word of 3D contact problem are
everywhere over the Internet.

The FEA solution of the 3D elastic contact problem
involving gears shall give the non-uniform pressure
distribution along the face width, plus the maximum
bending stress along the fillet.

Good luck for your further search!

 

[paulliu]

LMGK:

The following site lists some samples of FEA
for gear 2D and 3D contact problems:

http://www.ikonagear.com/casestudy_feaservices.html

 

[LMGK]

thanks paulliu, I have the gear models both for spur and helical tooth in patran(solver Nastran). I hope this helps me + ur tipps and links. Let me proceed and come with solns.

LMGK