Shaft loadings,
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Chaps,

bit of a tech question that I cant find the answer too,

Say you have two identical shaft and bearing arangements, but a flat pulley and a dished pulley, will the bending load increase despite the chain/belt line being the same?

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The bending load on the shaft will do i think as your feeding the forces in further down. There definately a lot more bending moments happening on the shaft and pulley.

it depends on the coupling between the green part and blue part. if the coupling is like a point load then the lower one has twice the force on the bearing (to skale) if we asume a rigid coupling and assume the blue bar is perfectly rigid then they will be the same. Real life will probably put the actual result somewhere between these two cases

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

in my eyes the bearing loadings will be the same

not that my eyes are any form of technical measuring instruments lol

Yes i moved to the darkside

Instagram @jdm_brett

id say the bearing load is the same if there is two bearings on the shaft
but if only one bearing on the shaft as you picture than id say the shaft wants to pull on an angle and act as a leaver

two chop sticks and put a rubber band between them acting as the chain or belt then your fingers as the bearings sort of thinking

putting two bearings on each shaft would stabilize them much better

The greater distance to the pulley mount on the shaft will mean you will see more bending moment at that bearing for the same belt/chain tension. What will complicate things is that the dished pulley (especially if really offset) will also be trying to twist on the shaft, giving rise to all sort of other forces, some of which may cancel the increased bending moment.

I'd go with somewhere between the same and double and probably design the shaft/bearing worst case (I doubt it would be much bigger).

You could probably get a computer model to simulate it. Or build it with a dummy shaft that wasn't too stiff and measure it by hanging weight off the pulleys.

Bending load at pully connection to shaft is greater but the force at the bearing is the same as the arm is shortened

That sir, is not rust, it is the progressive mass reduction system

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