I have a high-accuracy application for helical gears in an industrial environment. We’d like to print them to verify they do what we want. I’ve located online helical gear generators, but I’ve been unable to find online generators for the racks themselves.
I know there is one for fusion360 - however that isn’t an option. Stick with inventor only please. Anyone know of one, or is there a simple way of doing it?
I’ve always taken standard gear profiles and extruded along a helical path. I’ve never actually done it with racks but it should pretty easy to extrude or loft the profile. I’m a solid works user so I’m not sure exactly what features would be best in inventor.
There are some more quirks to make sure your geometry actually matches what you are helical generators are making for gearing.
Most gear geometry is given in the normal plane in either normal module or normal diametral pitch. This is where all the thicknesses and pressure angles are a clean number in the normal plane.
Occasionally gear geometry is given in the transverse plane. You can use some trig to go back and fourth between either, but I don’t have my formulas handy, but if you know which you have you can just draw your rack in the correct plane.
If starting from the transverse plane or transverse gear geometry:
For a rack you should just be able to draw the rack in one plane. Draw a line at the helix angle you would like the rack to be in a perpendicular plane. Then sweep rack sketch.
If starting from the normal plane or normal gear geometry
Then make a plane tilted at the desired helix angle. Draw a rack extrude it out further than it needs then cut the ends off to make a rack from a perpendicular plane.
Hopefully that helps and doesn’t just make things more confusing.
There are Feature Scripts for this in Onshape! We’ve used them before.