CVT CVT for use on gyrocopter prerotator. Is it possible?

[buggy064]

I'm still planning my gyro copter I was thanking of making two frame's maybe three to help pay for the more expensive parts I found some 6061 extruded aluminum at a decent price and a small machine shop that's not to expensive I also found a site that sells used parts, I thank gyrobee has a site where the sell a prerotator.

 

[HeadSmess]

talking to a mate that used to do this a lot...

talk of an alloy sprocket/ gear on hub, and some type of heavy duty cable drive with a gear/sprocket one end, and a rubber wheel that gets pressed up against engine flywheel. the shaft from a bent shaft brushcutter will do it with some wangling to fit.

other people get away with electric motors.

remember a hi-end cordless drill can break your wrist in low gear! chuck in a 3:1 redux via chain/pulley and some type of slipper clutch should do it to.

yeah ok, a pre rotator is handy so you dont have to do a lap or two of the runway first...


i think a lot of it will do on the hub setup. do the blades flap on a pivot while the shaft stays upright, or does the whole shaft/rotorhead flap? the first can be frame mounted with no issues, the other type would need to be mounted so it can pivot with the shaft.


lol. all them people that hate alloy frames with engines...a planes just pop riveted together! beat that

 

[beatlegeo]

I got those plans for a gyrobee it does not recomend preroter it makes it hevy more than a altralight. I did see like a starter motor push a button engages a sproket turns the rotor build up speed I thank I seen something like that on there web site it seems like it doesent takle to long if you push it with your hands.

Just watch out for the "Magic" 254lb limit, or you'll be jumping through the "$$$" Hoop! bg

 

[Frankenstein]

Uh... So helicopter like things and motorized bicycles have something in common? Uhm OK sure. Well the only small cvt I have experience with is the nuvinci hub, as far as gently getting the force from the motor to engage the props, well I'd go old school and go with a clutch, slowly letting the clutch engage with the hub, or better yet, letting the hub engage with the prop. I think if a very small frictional rubber surface was put onto the hub, then slowly allowed to begin rubbing the prop shaft then the cvt could ease it's way into engagement. The hub also has a freewheel mechanism, so if the rotor spins too quickly the cvt is "disengaged" from the engine preventing drag.

 

[Frankenstein]

Maybe the new part if this drawing helps, the hub also accepts some odd belt system too.

 

[darkfighter]

There is this cheap 50cc scooter by this Chinese company called Tao Tao, which uses a simple CVT technology to get good milage, whilst being street legal in all 50 states. However, there are known to be electrical issues and requires a substantial amount of tuning to be fully effective. This would be even harder without mass production testing techniques that you do not have access to, and even harder considering the performance curve of rotax and ultralight aircraft engines.