Involute Spline
Involute Spline
(OP)
I am trying to design a go gage for an involute spline. I have drawing the spline several ways but the when I draw in the pins and check the diameter it does not match up with the print. Can someone that has a program for creating these splines send me a dxf or something so I can find my mistake?? It is 16 teeth, pressure angle of 37.5 Degrees, tooth thickness of 2.090 +.058/-0.0 @ DP of 19.0mm. Minor Dia. is 18.2 +0.1/-0, major dia. 20.25 +0.1/-0. Once drawn you should end up with a pin dia. of 15.04 +0.05/-0 using 2.5mm pins.
Any help you may have would be great. I have attached my drawings if anyone is interested.
Thanks
Any help you may have would be great. I have attached my drawings if anyone is interested.
Thanks





RE: Involute Spline
your go ring gage is your max effective circular space width.
your no go is your min. actual circular space width.
The max actual circular tooth thickness is reference if
verified with an ring go gage.
In the 1970 version of the above book it is explained in pages 83 & on.
RE: Involute Spline
max circular space actual is used to calculate your no go plug gage.
minimum effective space width is used to calculate your go plug gage.
your minimum actual circular space width becomes a reference if a go plug gage is used.
you can not use wires to verify your min. effective size.
because it includes all of your errors, tooth index, lead,
involute ect. ect ect.
Hope that helps.
RE: Involute Spline
Thanks again for your help.
RE: Involute Spline
I can create the DXF for your wire cutter but it will cost you.
You can contact me via the link below.
Ron Volmershausen
Brunkerville Engineering
Newcastle Australia
http://www.aussieweb.com.au/email.aspx?id=1194181
RE: Involute Spline
Thanks for the response.
RE: Involute Spline
RE: Involute Spline
Thanks for looking.
RE: Involute Spline
To learn more about tooth profiling, gears and splines I suggest that you either go on line or get a current Machinist Handbook. The machinist Handbook has a table to calculate the many parameters of an involute tooth profile so that you can draw it in ACAD.
Good Luck!!
RE: Involute Spline
approximate it by using 75 degrees as the included angle.
The angle would actually be nearer 54 degrees from the
layout that I made. Is the 2.090 tooth thickness actually
the tooth space? Your drawing indicates an internal
spline.
RE: Involute Spline
I also have a dedicated program that draws gears or splines.
but I only use it on my projects.
if you do a search here on this board there was some one who wrote a lisp programe that would draw the Involute curve
of the gear or spline.
it was very simple to run in auto cad.
making gages is a tricky business. Normally it is verified with gear inspection equipment. since it is a gage, it is held to very tight tolerances. Spline gages are ground
.0001 max parrallel
.0001 max involute
.0003 max index error
however if it were a ref gage for manufacturing then it would be acceptable.
RE: Involute Spline
Thanks for the responce. Yes since the drawing in of an internal spline (that I want to inspect with and external gage) the tooth thickness shown would become the tooth spacing on the gage I want to construct. I understand these drawings I attached are incorrect I only wanted to show what I was trying to accomplish. I need a gage to check that the tooth thickness and pin diameter are correct. I dont even need to check the major and minor diameters. I thought I could do this with a straight tooth gage but after I started making drawings I realized I could not.
RE: Involute Spline
My reason for creating this "gage" is only a reference gage for manufacturing purposes. I am not looking to create a certified gage for inspection.
I tried to search for the forum you are speaking of becasue someone esle told me the same thing but all of them I find the links don't seem to work anymore.
RE: Involute Spline
a tooth space of the internal spline equal to your dimension
under 2.5 diameter pins.
Tooth thickness of 2.090 +.058/-0.0 @ Pitch Diameter of 19.0mm would be the tooth thickness of the external spline.
RE: Involute Spline
curve on the left hand side. You will have to use the pline command to draw a curve thru these points and trim
the curve at you minor diameter. I assume this is enough
accuracy for you. You will have to rotate the curve about 0,0 position until it is tangent to the pin diameter.
at point X=-1.690885 Y= 7.350665 Z= 0.000000
at point X=-1.693748 Y= 7.367844 Z= 0.000000
at point X=-1.697442 Y= 7.396875 Z= 0.000000
at point X=-1.701055 Y= 7.438197 Z= 0.000000
at point X=-1.703616 Y= 7.492355 Z= 0.000000
at point X=-1.704068 Y= 7.560010 Z= 0.000000
at point X=-1.701227 Y= 7.641947 Z= 0.000000
at point X=-1.693744 Y= 7.739084 Z= 0.000000
at point X=-1.680055 Y= 7.852489 Z= 0.000000
at point X=-1.658317 Y= 7.983384 Z= 0.000000
at point X=-1.626330 Y= 8.133159 Z= 0.000000
at point X=-1.581440 Y= 8.303379 Z= 0.000000
at point X=-1.520415 Y= 8.495787 Z= 0.000000
at point X=-1.439287 Y= 8.712295 Z= 0.000000
at point X=-1.333145 Y= 8.954966 Z= 0.000000
at point X=-1.195867 Y= 9.225962 Z= 0.000000
at point X=-1.019774 Y= 9.527449 Z= 0.000000
at point X=-0.795173 Y= 9.861437 Z= 0.000000
at point X=-0.509750 Y=10.229495 Z= 0.000000
RE: Involute Spline
Thanks, I will punch it in and see what I get.
RE: Involute Spline
Pressure angle of 37.5 Degrees
Tooth space thickness of 2.090 +0.058/-0.000 @ DP of 19.00mm
Minor Dia. 18.20 +0.10/-0.00
Major Dia. 20.25 +0.10/-0.00
Dimension under 2.50mm Dia. Pins of 15.04 +0.05/-0.00
Involute curve at max dimension under pins, tooth space 2.148mm
at point X=-1.602870 Y= 8.729057 Z= 0.000000
at point X=-1.541855 Y= 8.881664 Z= 0.000000
at point X=-1.407398 Y= 9.167433 Z= 0.000000
at point X=-1.231111 Y= 9.488064 Z= 0.000000
at point X=-1.001721 Y= 9.846206 Z= 0.000000
at point X=-0.704680 Y=10.244040 Z= 0.000000
at point X=-0.542074 Y=10.429985 Z= 0.000000
These are coordinates from minor diameter to major diameter.
RE: Involute Spline
Thank you for the points, that was exactly what I was looking for.