Machining a gear

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How would one about machining this gear?
What would it be called as far as seeing if one is available to buy online?
horse1.jpg
 
That would be called a crowned ball gear. I have seen those in use on very old aircraft control yokes.

Mark T
 
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If the center gear is .500” front gear 1.5” to 2”?
 
The pitch Ø should be the same for the forward as for the aft, if you want the legs to move in sync. I believe this was meant for a kid to ride on.
I would set my indexer on the rotary table to get the correct arc on each gear peak/valley. Kinda hard to explain.

Modulus of 1 (metric) with 20 degree pressure angle would work for your scale. That way you could test with lego gears too before committing.

I think a swash plate would work better but the complexity would make it a fun project!

@dnalot What aircraft were those on? That's pretty interesting.
 
What aircraft were those on? That's pretty interesting.

I don't remember. It was a museum exhibit of WW 1 planes and they were only displaying the yoke assembly to demonstrate how the controls worked.

Mark T
 
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I think part of the issue is the patent drawing has an error. The teeth are shown in a mirror image symmetrical to the pivot point. They would all curve in the same direction. Still sort of a hassle to make, but as there is little power being transferred a less than perfect fit will still work as long as it isn't so loose that the gadget works poorly. For a small model I'd be inclined to 3D print at least the "weird" gear and see it the gear outlasts the novelty of seeing it work :) 3D printing all of the gears might not be a bad idea, just add enough meat to carry the pins / shafts that couple to the actuating arms/lever. Keeping the legs as light as possible would be important as there is quite a bit of leverage there.

Looks like a fun little gadget, could be a nice project for those who like automata / mechanical toys.

Cheers,
Stan
 

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