Star wheel drive. Information needed.

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koirat
Posts: 66
Joined: Tue Oct 05, 2021 5:24 pm

Star wheel drive. Information needed.

Post by koirat »

Do you know the Star Wheel drive like that one ?
https://www.youtube.com/watch?v=TaZKjLB-KVU

I need information how to draw it and size it proceduraly.
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Roy_043
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Re: Star wheel drive. Information needed.

Post by Roy_043 »

koirat
Posts: 66
Joined: Tue Oct 05, 2021 5:24 pm

Re: Star wheel drive. Information needed.

Post by koirat »

Geneva Drive and Star Wheel drive is a little different.

Take a look at my current solution:
GenevaProblem.png
GenevaProblem.png (12.04 KiB) Viewed 1102 times
This system will turn the cross 180 deg in one cycle.

It is what I need but the problem is how close to the center of the cross the pin will be (red point on a picture) I will need a very high torque for this point since there will be a load on the shaft attached to the cross.

Now it looks like the star wheel have this point much further from the center so It will trade acceleration <=> torque.

If there is a better solution than those above to solve my problem, please share.
dxp.dev
Posts: 280
Joined: Tue Dec 11, 2018 12:57 pm

Re: Star wheel drive. Information needed.

Post by dxp.dev »

koirat wrote: Sat Oct 23, 2021 5:31 pm If there is a better solution than those above to solve my problem, please share.
In the video, the "arms" begin at a way more distant point from the axe as in your screenshot. If you're not constrained by the distance between the 2 axes, I would suggest to do that too.
Find your user.cfg and system.cfg files : Macro_findConfigFiles

Imperial system makes no sense, go metric ! ! !
koirat
Posts: 66
Joined: Tue Oct 05, 2021 5:24 pm

Re: Star wheel drive. Information needed.

Post by koirat »

dxp.dev wrote: Sat Oct 23, 2021 7:33 pm
koirat wrote: Sat Oct 23, 2021 5:31 pm If there is a better solution than those above to solve my problem, please share.
In the video, the "arms" begin at a way more distant point from the axe as in your screenshot. If you're not constrained by the distance between the 2 axes, I would suggest to do that too.
As I know you cannot move Geneva wheel and cross apart as you want.
It is the math that dictates the distance and length of pin slots.

If you got an example I will gladly see it.
But every example of 4 slots cross I saw on the internet got the problem I have mentioned (pin slot to close to the center)
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