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Paradoxical Gear Sets
- jacquesm 13y agoThat's beautiful stuff. Gears are fascinating in their own right, these gears doubly so. As a kid I would disassemble (for the most part, sometimes I managed to put things back together again) all kinds of stuff and my favorites were alarm clocks and regular clocks. I must have destroyed what today would be worth a small fortune of clocks. Gears always fascinated me, they look so simple and yet they're quite complex. The beginnings of the industrial revolution were grounded to some extent in the clock making industry, to aid the sea going nations. Cutting the gears for those clocks required a degree of precision that had not been seen for a long time and from that clock making industry we got to portable clocks (watches), mechanical computers and so on.
- nraynaud 13y agoThey just love it in French engineering schools. They bring it on the day of the test, if you make an odd number of sign error you completely miss the trick, if you check your results for general coherency you'll never believe they are rotating in the same direction and you'll loose quite some time checking your stuff.
- stefantalpalaru 13y agoAre they still gears if they are powered independently and the only connection between them is that they may come in contact without blocking each other's rotation?
- taejo 13y agoI think that one is driving the others (in the first video it looks like the motor is only powering the middle gear)
- mcv 13y agoThe "Paradoxical Gears Explained" video shows a belt behind the gears. That suggests it's not really the gears driving each other.
- nkurz 13y agoThey are driving each other. Although not well explained, the belt is just used to demonstrate how the angles are determined. This is a little clearer (although still hard to follow) if you watch the "Standard Gear Explanation" video first: http://www.youtube.com/watch?feature=player_embedded&v=lWuKl4rG2HA http://www.youtube.com/watch?feature=player_embedded&v=lWuKl...
- stefantalpalaru 13y agoYou're right. These 3D printed gears are clearly driving each other: http://www.youtube.com/watch?v=qGAnmRb66s0 http://www.youtube.com/watch?v=qGAnmRb66s0
- twiceaday 13y agoImagine screwing in a screw. Rotation makes lateral movement. Imagine pushing in a sharp-ended screw into something soft. Lateral movement makes rotation. What I believe is happening here is that one screw is being rotated, generating a lateral force on the other screw, rotating it.
- Someone 13y agoSee also: http://www.shapeways.com/model/458290/magic-gears.html http://www.shapeways.com/model/458290/magic-gears.html. 3 identical gears that, depending on the way they are assembled on their axes, behave like normal gears or paradoxically.
- cousin_it 13y agoOh, I see. Normal gears can be flat, but paradoxical gears have to be 3D, they're like a pair of corkscrews driving each other. Right? Is there friction at the points of contact?
- ZoF 13y agoParadoxical gears both rotate in the same direction.(e.g. both clock-wise) Normally gears rotate in opposite directions, meaning the gear on the left rotates counterclockwise and the gear on the right rotates clockwise(or vice-versa). It just so happens that any paradoxical gear has to be "3D"(no 2D solution), there are "normal" gears that are 3D though.