Involute Spline Editing

[matt.murray]

Hello all,

I have an internal involute spline I am trying to generate geometry for. The criteria it needs to meet is:

Fillet Root Side Fit Class 7

PA 30

Pitch 32/64
Teeth 10
Form Dia. .348
Base Dia. .2706329

.379 Major Dia.
.3125 Pitch Dia.

Circular Space Width
Effective Min = .0491
Actual Min = .0539

I am able to generate the spline inside Inventor 2021 with the only discrepancy being the Major Dia. as shown:

Internal Involute Spline Data
ANSI B92.1 - 30 deg, Fillet root, Side fit
Number of Teeth	N	10.000 ul
Pitch	P/PS	32.000 ul/in/64.000 ul/in
Pressure Angle	α	30.00 deg
Base Diameter	Db	0.271 in
Pitch Diameter	D	0.313 in
Major Diameter, Internal	Dri	0.369 in
Form Diameter, Internal	DFi	0.348 in
Minor Diameter, Internal	Di	0.281 in
Circular Space Width
Max Actual Circular Space Width	s	0.054 in
Min Effective Circular Space Width	sv	0.049 in
Max Measurement Between Pins	Mi	0.242 in
Pin Diameter, Hub	dp2	0.054 in

Is there any way for me to modify the major dia. to create the appropriate geometry?

Thanks!

[WHolzwarth · Accepted solution]

I only could do it with some manual work. 2020 files in Zip

[matt.murray]

Wow, that is fantastic! Thank you! I need one more modification, the Minor Dia. needs to be .2865. Can you explain how you manually edited the initial spline to provide the file?

Thanks!

[WHolzwarth]

Hi Matt, here's the updated file. I didn't change the involute spline itself, but only did a replace face operation at the major dia, and a trimming at the minor dia. Adding fillets, splitting for only one tooth and patterning it all around.

Just move EOP up and down step by step. Most of the workflow is self-explaining.