profile shifted spur gear/pinion

[NRMengg]

Hi,
I need help on finding correct formula for addendum and dedendum calculations for profile shifted spur gear/pinion.

thanks
NRM

 

[israelkk]

This is not a subject you can summarise in one formula. This is an advanced subject in gear design and you need to invest some time to grasp the subject. I suggest you search and study some books and literature of gear design. These books are usually out of print and quite expensive. You can try to find them on bookstores on the net. One really cheap book (~$12) reprinted in India is Handbook of Gear Design from Maitra. The issue is extensively explained there.

 

[dimjim]

You can find the formulas in Machinery's Handbook and as
Israelkk suggests, you have a learnning curve to straddle
but one step at a time. Good luck to understanding profile shifts and long and short addendum gearing and are also called recess action gearing.

 

[NRMengg]

thanks Israelkk and dimjim,
I will look at maithra handbook.
Till now I was looking at qtcgears.com
I know that gear calculations with profile shift is not easy subject to understand.

Here is some more info on which i am working.
Spur gear
Module 18
Pinion 17 teeth, Gear 151 teeth
working center distance 1529.28mm
Profile shift- x1= +0.5 and x2= +0.5

I have calculated as per info on qtcgears.com
Addendum=(1+y-x2)m for pinion and =(1+y-x1)m for gear with centre distance increment factor y=0.96025
i am getting addendum 26.284mm for pinion and 26.284mm for gear.

But gear supplier is mentioning addendum 23.451 for pinion and 9.666 for gear. (backlash max.1.139mm and min 0.639mm)

I want to know which is correct? Is backlash making so much difference?
thanks,
NRM

 

[dimjim]

If the working center distance 1529.28mm
is correct for the system, you are
nearer to the solution than the vendor.

1.00 plus .50 yields 1.50 x 18 = 27 addendums
for both pinion and gear. Since you have not
stated the pressure angle, I cannot calculate
the working center distance. If the backlash
is the total backlash in the system, it does
seem reasonable for that large of a gear.

 

[NRMengg]

Thanks dimjim,
Pressure angle - 20deg
Backlash mentioned is Total backlash

nrm