Freewheling devices are used in drivetrain of helicopters, microcars, bicycles to automatically decouple spinning rotors/wheels from idling/stalled engine:
- At bicycles it enables rolling without spinning pedals.
- At two-stroke engine powered microcars (eg. the infamous East German microcar Trabant), it eliminated engine braking, as two stroke engines run terribly badly in engine braking mode
- At helicopters (combined with centrifugal clutch) it allows starting and warming engine in idle race, while rotors are still standing. Moreover, in case of engine stalling, it disconnects spinning rotors from stalled engine, preserving rotor inertia for autorotation gliding mode being vital for successful crash-landing.
We designed two versions:
A, Smaller sized (3.38 studs diam × 3 studs lenght), low torque tolerance version, which acts as a centrifugal clutch also.
B, Bigger sized (4.25 studs diam × 4 studs lenght), high torque tolerance version, with ratchet mechanism controlled by rubber springs made of part 'rubber damper 2×1×1 studs'