Formula for Transverse Backlash

[jackboot]

What is the formula to determine transverse backlash in helical gears?

I have an old paper but I can't read it and I can't find the formula on the internet.

So far I have: Bt=Bn/cos(pressure ang)

However, I believe I am missing one other variable.

jackboot

 

[EnglishMuffin]

You are indeed missing one other variable.

Bt=Bn/(cos(alpha)*cos(beta))

Br=Bn/(2* sin(alpha)*cos(beta))

Where Bt = circumferential backlash
Br = radial backlash (just for info)
Bn = normal backlash
alpha = operating transverse pressure angle
beta = Base helix angle

Hope that helps

 

[jackboot]

Thank you very much.

jackboot