Auto-shifting 2 Speed AND motor brake/reverse?

[BrianG]

I was thinking (uh-oh). I don't know of any auto-shifting two speed transmissions that also use the motor for brake and reverse. The OWB on first gear generally makes this impossible, which leaves you with mechanical brakes and no reverse - although some trannys like the Revo do allow for mechanical reverse, but they are brittle.

But, why not use another gear on a OWB, except flip the OWB around so it only engages when the motor spins the other way (which would also give motor braking). I did a quick diagram using the Revo tranny as a base design to illustrate:



While the motor is spinning forwards, first gear will provide the drive. Once a certain rpm hits, the centrifugal clutch on second gear kicks in. Since the shaft is spinning faster than first gear, the OWB allows first to free-wheel. Nothing new here. But, during all this, the reverse gear set in the diagram above is free-spinning due to its flipped OWB, and is essentially doing nothing.

When you brake or engage reverse, the centrifugal clutch lets go and the OWB on first gear free-wheels. So both first and second gears are doing nothing. But the OWB on the reverse gear set is now engaged allowing the motor to brake and/or reverse.

How does this sound?