mr.electric
10 kW
I saw this bike at a trade show:
http://www.izipusa.com/59-izip-express-electric-bike.html
I have been interested in ebikes since the ev warrior days and have never seen anything like this. I saw the drive system on this bike and it baffled me. The very strange part is that the axle from the rear hub is not mounted into a standard dropout. The axle goes into a pillow block type bearing and spins relative to the frame. The motor has a toothed belt that goes to a sprocket on the rear hub which is not unusual. The pillow block bearing on the axles is new and different. The Currie rep said it automatically gives a good balance of motor and pedals. A swiss company designed it.
Here is a description:
The bikes feature a unique differential planetary hub system which is propelled independently yet simultaneously by two drive systems - electrical and human powered. Because of the differential, neither system bogs down nor negatively impacts the other. Both operate at high efficiencies and optimum performance.
A power sensor detects pedaling motion and crankshaft speed via a microprocessor and sends a corresponding signal to the electrical motor to supplement human power on the other drive system. While not a true torque sensor in the original sense of the word, the effect is just that thanks to the dynamics involved in the differential system and thus extra pedaling effort is rewarded by the creation of a variable amount of electric push - rider selectable - to overall propulsion.
the bike shown in the pics has a standard derailer. The bike I saw at the trade show actually had an internal shifting hub mounted on the same bearing- drop outs. There was no shift lever or cable it actually shifted automatically - some how !!!!!
can anyone conceptualize how this differential gearing works? I still don't "get it".
http://ds1.dreifels.ch/prozweb/index.htm
http://www.izipusa.com/59-izip-express-electric-bike.html
I have been interested in ebikes since the ev warrior days and have never seen anything like this. I saw the drive system on this bike and it baffled me. The very strange part is that the axle from the rear hub is not mounted into a standard dropout. The axle goes into a pillow block type bearing and spins relative to the frame. The motor has a toothed belt that goes to a sprocket on the rear hub which is not unusual. The pillow block bearing on the axles is new and different. The Currie rep said it automatically gives a good balance of motor and pedals. A swiss company designed it.
Here is a description:
The bikes feature a unique differential planetary hub system which is propelled independently yet simultaneously by two drive systems - electrical and human powered. Because of the differential, neither system bogs down nor negatively impacts the other. Both operate at high efficiencies and optimum performance.
A power sensor detects pedaling motion and crankshaft speed via a microprocessor and sends a corresponding signal to the electrical motor to supplement human power on the other drive system. While not a true torque sensor in the original sense of the word, the effect is just that thanks to the dynamics involved in the differential system and thus extra pedaling effort is rewarded by the creation of a variable amount of electric push - rider selectable - to overall propulsion.
the bike shown in the pics has a standard derailer. The bike I saw at the trade show actually had an internal shifting hub mounted on the same bearing- drop outs. There was no shift lever or cable it actually shifted automatically - some how !!!!!
can anyone conceptualize how this differential gearing works? I still don't "get it".
http://ds1.dreifels.ch/prozweb/index.htm