Posted by colin on August 08, 2009 at 08:24:15:
In Reply to: gear fomula posted by mark fenn on August 04, 2009 at 15:09:42:
Mark
As you haven't acknowledged my e-maill I list below the full calcs in case you didn'get them.
Contact Ratio= 1.13
DP 8.00
Pressure angle 20.0000
Operating Pressure Angle 26.9960
Helix angle 30.0000
Hob tip rad. 0.0000
Centre dist. 4.3310
Pinion
======
No.of teeth 23
AMC 0.7636
Addendum 0.2204
O/Dia. 3.7347
(O/D reduction) 0.0259
Root/dia. 3.1982
Hob Offset 0.0954
Total tooth depth 0.2683
Wheel
=====
No.of teeth 35
AMC 0.4997
Addendum 0.1875
0/Dia. 5.4008
(O/D reduction) 0.0259
Root dia. 4.8642
Hob Offset 0.0625
Total tooth depth 0.2683
Measuring data
==============
Min.total backlash .008
Max.total backlash .008
Fraction of b.lash on pinion .5
Pinion Hob/Cutter Offset for mean backlash = 0.0039
Wheel Hob/Cutter Offset for mean backlash = 0.0039
Pinion data:-
------------
Base tan.length over 5 Teeth 1.7824
Dist.across 0.2160 Dia.pins 3.7599
-----------
Wheel data:-
------------
Base tan.length over 7 TEETH 2.5295
Dist.across 0.2160 Dia.pins 5.4500 / 5.4500