What are the ways to regulate RPM of a gear-system powered by a coil-spring. I know of escapements used in clocks, but the output isn't smooth.

How do old mechanical gramophones ensure constant RPM output?

 

>How do old mechanical gramophones
>ensure constant RPM output?

They use spring loaded hinged arms that expand away from the center of rotation like a ice scatter spinning fast when her arms are near her body and slowing as she extends them out.

The spring is along the vertical rotating axis. There are two arms for balance purposes and they are attached to the rotating center shaft. One end of each arm is able to move up and down the shaft and is spring loaded. The spring forces the arms toward the center of rotation. As rotation increases the arms which usually have weighted balls at the elbows, extend outward and compress the spring along their axis and slows the rotation. Sort of like putting your hand together above your head then moving your arms to the top of your head which extends your elbows out from your body.

I hope I have explained it well enough so you can picture it. <I>

 

I believe that you refer to centrifugal pendulum based governor used in diesel generators to control the throttle opening. However, in our instance, how is the braking effect realised by the governor in principle?

Thank you for the reply.