Cast aluminum and wood (painted) on a vertical panel.
For educational use only. All rights reserved by the contributor(s) and publisher(s).
gears, endless screw, worm
This combination shows the method of changing rotation of driven gear. Note the right and left hand angle of the threads in the continuous screw or worm. Teeth in lower gears have corresponding left and right angles. The threads of these worms are of the multiple type and have five leads while that in No. 72 is a single thread, having only one lead.
[Virginia Downward & William M. Clark, 1930]
This model illustrates a another version of an "endless screw" mechanism. An example is in the Reuleaux-Voigt Collection, model C-9. The endless screw or worm drive gearing was also used by Renaissance engineers such as Leonardo da Vinci. See example his Codex Madrid, Folio 17 verso. [To access on line see KMODDL references.] FCM