Using values to derive the general shape of a rotor

[Rx7Evan]

Originally Posted by NoDOHC

If you are really serious, I have a good set of measurements (actually parametric equations, which you can plot and extrude in Solid works or ProE).

I am not good at computer drawing, or I would model them myself.

PM or post here if you want the data.

After looking at the data you sent me about four times i finally realized what was going on. So I walked down the hall and got one of the RF analysts to plug the equations into MatLab. The epitrochoid housing curve came out quite nice, but the equation you gave me for the rotor gave some funky results. They could have made a mistake punching it in.

Shouldn't I be able to interpolate the correct shape of the rotor from the housing curve? If one apex is centered at the neck of the epitrochoid curve (narrowest center point), then the opposing apexes will be on the housing and the center of the face between them will be tangent to the opposing "neck". There is only one arc that will solve that. It will be somewhat untrue because the rotor wouldn't actually be modeled with apex seals... Need more data for that.