Offset sprocket/cam in linear->rotational system?
Offset sprocket/cam in linear->rotational system?
(OP)

Easy picture example
A pneumatic piston pulls back on a tray, which has chain attached to either end, wrapped around a sprocket, causing a shaft to rotate.
My thought is that if I offset the shaft and turn the sprocket into a sort of cam, I can increase low end torque and high end velocity, but I have no idea how to calculate this as the chain is completely wrapped around the sprocket it isn't clear where I should be calculating force from, i'm assuming that I should be calculating mechanical advantage against the part of the sprocket closest to the side that is being "pulled" from the chain, so in the image example the shaft in the new design would be giving the desired behavior.





RE: Offset sprocket/cam in linear->rotational system?
Maybe you need to build a fast throwaway prototype to understand the problem.
Mike Halloran
Pembroke Pines, FL, USA
RE: Offset sprocket/cam in linear->rotational system?
Should have quit one sentence sooner.
RE: Offset sprocket/cam in linear->rotational system?
my instincts tell me that at any given point I should be calculating mechanical advantage from where the pulling side of the chain first contacts the sprocket at that particular moment in time, a real quick mockup I made seems to behave in that way but I'd rather know the real math for fine tuning before I invest in it rather than just wing it.
RE: Offset sprocket/cam in linear->rotational system?
RE: Offset sprocket/cam in linear->rotational system?
Not so much, with a roller chain.
Mike Halloran
Pembroke Pines, FL, USA
RE: Offset sprocket/cam in linear->rotational system?
je suis charlie
RE: Offset sprocket/cam in linear->rotational system?
RE: Offset sprocket/cam in linear->rotational system?