Gearmotor Clutch to protect output gear

Additional info: 0.5-1.0 HP
Application: automotive, comm'l

Why not put a limit switch on the
output of the motor? Is it hydraulic,
electric or ? I think this would be
a cheaper solution.

My preference is limit switches in this electrical actuator, but the customer sometimes dictates the config. Another approach is a current limiter, which creates high resistance at overload. Upon removing the voltage, the current limiter quickly resets. The current limiter is not an option here because there is one already: slow acting and rated at high current.

The following designs went to production:

- Gear on shaft with collar; belleville spring behind it with adj nut. A little complex but compact.

- A one way ratchet clutch made from plastic. The tapered fingers were acetal. A two way clutch could be made the same way by changing 90 deg stops to 45 deg.

- USA Tolerance Rings (dot com) is showing a tolerance ring for limited slip gears on shafts. The mfr says that it has to be developed on an individual basis.

Any other ideas for simple clutches?