Combination of nut-screw and worm mechanisms gives the jack a high mechanical advantage.
Inventor files for this video are available at:
http://www.mediafire.com/download/2ezhxbc5n43qlbs/WormJackInv.zip
STEP files:
http://www.mediafire.com/file/ljq28myzfk8x95k/WormJackSTEP.zip
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