Summary

I am building a Geneva Mechanical Index project, I needed the indexed movement on the Geneva Wheel to be fast, but I needed the stationary duration of the indexed movement to be longer, the answer for me was to use an Intermittent drive.

The simplest way to achieve what I needed was this, referred to as "Mutilated Gears".

Print Settings

Printer:

Tiertime Up Plus 2

                                            <p class="detail-setting rafts"><strong>Rafts: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting supports"><strong>Supports: </strong>                     <div><p>No</p></div></p>                                                                                <p class="detail-setting resolution"><strong>Resolution: </strong>                     <div><p>.25</p></div></p>                                                                                <p class="detail-setting infill"><strong>Infill: </strong>                     <div><p>90%</p></div></p>                                                    <strong>Filament:</strong> OEM ABS                N/A but Green

Post-Printing

Clean up inner edges and surfaces of gears as needed for smooth movement.

How I Designed This

Mutilated Gears:

            <div><p>The larger gear will engage the smaller gear, the ratio of the gears is 2:1.<br>I have removed 1/2 of the teeth on the larger gear, so it only engages the smaller gear for half the rotation and a intermittent period resulting in a 1:1 ratio on the smaller gear with a dwell period for half a revolution of the primary gear. </p><p>The small gear was designed with 15 teeth and the larger with 30, I found I had to remove 15 +1 extra tooth of the larger gear, resulting in only 14 teeth on larger gear.<br>The best way I can explain this at the moment is the 1st tooth normal starts over the starting tooth on small gear, to pull the 1st tooth on the smaller gear, in the mutilated design, the second tooth starts by pushing the 1st tooth on the smaller gear</p><p>Good reference on various types of indexing methods<br><a rel="nofollow" href="http://www.roymech.co.uk/Useful_Tables/Cams_Springs/Indexing.html">http://www.roymech.co.uk/Useful_Tables/Cams_Springs/Indexing.html</a></p><p>I use Rhinocerous to do my design and modeling, Its what I know how to use.<br>I designed the gears using Inkscape.</p></div>

Intermittent Gears