Shaft Friction Control: Simple Solutions

AI Thread Summary
The discussion focuses on finding a simple solution to control resistance on a rotating shaft without adding extra weights. Suggestions include using a DC motor for torque generation, implementing eddy current braking with a conductive disk and magnet, or utilizing a Prony brake. The original poster clarifies that the shaft is wind-driven and does not have specific torque requirements. Participants inquire about the shaft's specifications, such as blade length and wind speed, to provide more tailored advice. Overall, the conversation emphasizes practical instrumentation options for increasing resistance on the shaft.
mechit
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TL;DR Summary
Shaft friction control
Hello Everyone,

I'm working on a future mechanical structure with a rotating shaft. In this project, I should be able to control the resistance on the shaft but instead of adding some extra weights on the shaft to increase inertia, I don't have any ideas. Does anyone have an idea of simple instrumentation (sort of a brake) to add on the shaft so that it helps to increase resistance on it?

Thanks a lot
 
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Welcome to PF.
How much torque do you require?
How fast does the shaft rotate?
You could use a DC motor with a continuous current to generate the torque.
You could use a conductive disk with a fixed magnet to give eddy current braking.
Or go old style ... https://en.wikipedia.org/wiki/Prony_brake
 
Thank you for your reply!
Actually, I don't have a specification for the torque because it is a shaft that rotates thanks to the wind. A blade will be fixed on it.
I will look at your recommendation
Thanks a lot
 
What is the radius = length of one blade ?
What is the wind speed ?
 
Is it vertical or horizontal?
Are you wanting to stop its rotation from a high speed or just slow it? What is the approximate weight of the rotating mass?
 
mechit said:
Does anyone have an idea of simple instrumentation (sort of a brake) to add on the shaft so that it helps to increase resistance on it?
I don't understand, a brake is a "sort of brake". Sure, there are many models, but they pretty much all work the same.
mechit said:
I should be able to control the resistance on the shaft but instead of adding some extra weights on the shaft to increase inertia, I don't have any ideas.
If increasing inertia is what you are looking for, you don't have to add extra weight, you can just move the ones already there away from the center of rotation.

 
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