Using a bimetallic coil to turn a pulley

AI Thread Summary
The discussion revolves around using a bimetallic coil to turn a pulley, with inquiries about calculating the thermal "spring constant" based on geometry and material properties. Participants explore the feasibility of this concept for heavier work, referencing similar actuation mechanisms like those in thermometers and carburetor stoves. There is a focus on determining the angle of revolution as a function of temperature gradient and the necessary parameters for effective operation, such as the number of turns in the coil and the size of a counterweight. The conversation highlights the need for clarity in terminology, particularly regarding the terms "spin" and "rotate." Overall, the thread seeks insights into practical applications and calculations for this mechanism.
ENgez
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Hello,

I am looking at the possibility of turning a pulley using a bimetallic coil embedded inside.

How can I calculate the thermal "spring constant" of the coil, as a function of geometry and material properties?

Does anyone know of devices with similar actuation mechanisms?

thank you.
 
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ENgez said:
pulley using a bimetallic coil embedded inside.
... and, working against what? Sounds like a metal tape measure, but I can't describe that as a "pulley."
 
I attached an illustration to further clarify.

Will this work? If so, How can i calculate the angle of revolution as a function of temperature gradient?
 

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ENgez said:
similar actuation mechanisms?
http://www.coleparmer.com/Brand/Buy_More_Save_More_on_Bimetal_Thermometers/2262?referred_id=20965&gclid=CNvZ9anWx8cCFUGUfgodiFwCdA
 
Thank you for the reply.

I am aware that bimetallic coils are used to drive the needle in a thermometer.

What I am asking is if this concept can be used to do heavier work, like spin a pulley (wheel), and If there are examples of such mechanisms.
 
ENgez said:
like spin a pulley (wheel),
I keep tripping mentally over the word "spin." You say "spin," and I will think "rotate," and we'll proceed. "Carburetor stoves" are controlled by exhaust manifold dampers https://www.google.com/?gws_rd=ssl#q=exhaust+manifold+damper&tbm=shop
Number of turns in coil, plus size of counterweight, plus 90 degree rotation --- enough to go on?
 
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