[TheForge] Re: Flatbelt excitement

[xlch58 at swbell.net]

Mike Spencer wrote:

>garrickp> Make a clutch system that transfers power when the load
>garrickp> shaft is rotating slower or equal to the power shaft, and
>garrickp> disconnects when the load starts rotating faster than the
>garrickp> power. (See an engine starter or gas powered hobby car's
>garrickp> clutch for practical applications)
>
>I think that would require engineering and millwrighting beyound my
>skill or means.  The clutch would have to go in and out once each rev
>at 900 RPM.  (It may well be that 900 RPM on a flat belt is a Bad
>Thing, however.  I should look up the ft/s numbers for the belting.)
>  
>

All it takes is a sprague clutch, also called an over running clutch.  
MSC and McMaster Carr sell them, though I haven't bought or even checked 
on sizes appropriate for your application.   If you are having a 
resonance problem, they do have a tendency to grenade,otherwise they 
work fine.

>garrickp> Alternately, modify your hammer's balance so there's a
>garrickp> constant load instead of assymetrical load.
>
>I've wondered why they didn't go with a counterbalanced flywheel at
>the factory.  Perhaps they figured that, with a massive electric motor
>and a gear drive, it was unnecessary extra weight.  I don't think
>I'd attempt that mod except as a last resort (which is still far
>away).  It would involve drilling holes in the gear/flywheel and
>bolting on a couple or three hundred pounds of lead.
>
>Thanks for keeping me thinking, though.  About 3/4 done with the
>garden planting.  Puff puff.
>
>- Mike
>
>  
>