Satisfying Dual Stage Planetary Gears

thingiverse

Satisfying Dual Stage PlanetaryGears1.2: New! Now reports a calculation of the gear ratios in the text console! The zip file actually updated NOTE: See attached libreoffice .ODT file with the formulas. This is a library. Using OpenSCAD and the SatisfyingGears1.7 involute gear library (https://www.thingiverse.com/thing:3022677) and Satisfying Planetary Gears (https://www.thingiverse.com/thing:4099879) we can design dual stage planetary gear sets. The principle is that torque should be applied between the sun gear and ring gear of stage 1 by a motor or what ever. The planet gears if stage 1 and stage 2 should be connected but this is left to the user. The output torque should be used between the stage 1 ring gear and the stage 2 ring gear (output). The stage 2 sun gear is just an idler. To adjust the parameters you will need to set the DesignMode flag = true. This will display the Stage 1 and Stage 2 gearsets as flat polygons. The stage 2 set will be offset so you can see both sets at once and detect interference. Read the console messages as some combination just do not work and some are better than others. It will show error text of the teeth counts do not work. READ THE CONSOLE IN OPENSCAD. I made the default as chevron gears (Layers = 2) with the intent that we print these in place. If you find this impracticable set Layers1 and Layers2 = 1 so you can assemble the gears. You have to play with it. Anyway. This is just the gear geometry and in order to use these in a gear box you have to design the rest of the structure. I suspect dowels and screws and nuts may help. Research needed. Good luck and just ask if you have questions. I intend to use it for actuators in the future. Version 1.0: found an issue. We are not limited to the second stage having an exact opposite gear teeth counts. Just the center distance must be the same. Version1.1: You now must select the number of teeth on the second stage planet gear. "PlanetTeeth2" Version1.2: The same as Ver1.1 only it now reports a, hopefully correct, set or gear ratios in the console. It depends on how you configure your gear box. The attached .odt file has the math formulas. Please leave comments is you notice errors or need help with it.