On Monday, November 20, 2017 at 10:19:06 PM UTC-5, Jon Elson wrote:
wrote:

On Monday, November 20, 2017 at 2:30:40 PM UTC-6, N_Cook wrote:
A sort of slip clutch in a gear train that transmits torque until ther
is a jam. Then at a preset back-torque a "ratchet" mechanism engages
making a clicking noise as the drive side turns relatively freely to
protect a motor etc and alerts a user to a problem.

Over-running clutch?

No, an overrunning clutch allows it to slip in one direction and grab in the
other. That is a different mechanism used for a different purpose.

Jon

Like a bicycle freewheel.