Orbital wheel
The orbital wheel (or hub-less wheel ) is a wheel that is not held by a hub in the middle, as is normally the case , but on the circumference of the wheel ("orbit") . With this wheel design, the hub of the rim is the same and the axle is attached to the hub within the circumference of the wheel.
The orbital bike was invented by Franco Sbarro , who built a variety of working orbital bikes (including two motorcycles and a car, the 1989 Sbarro Osmos). It was patented by GlobeHolding SA in Geneva.
Tolerances, power transmission and materials have not yet been fully researched, so this bike has not yet reached its full technical potential.
Orbital wheels are also required for winding toroidal transformers as wire storage rings , see toroidal winding technology .
Guide geometry
In principle, orbital gears designed as a circular ring can be guided - radially - inside or outside, or else combined inside and outside.
The guide against axial evasion is mostly realized via the form fit of the entire part or web in a groove (groove) of the radial guide elements.
The radial guidance is typically distributed at 3 points over positions on the ring that are more than 180 ° apart.
2 guide points are sufficient if gravity is also used for holding. A chain of ring-shaped links is held in place by the tensile force.
If it is only held in one place, even if an additional force acts on the ring, there are still different possibilities of movement, such as with the curtain ring on the curtain rod or the hula hoop on the human body.
A management position can take on more complex management tasks if it has been trained partially or fully. A hollow torus with a slot on the inner or outer circumference can be guided alone (rotatable) by an internally fitted torus segment that is fastened via an external web.
Bending stiffness
A rim with tension spokes becomes very pressure-resistant radially due to the spoke tension. An orbital wheel has to provide its rigidity by itself and therefore has to be a little more voluminous. The Ferris wheel pictured has an internal tube framework for this. Bicycle wheels with fewer spokes, right down to the trispoke (three-spoke wheel), also have rims that are radially higher.
See also
swell
- A Bicycle Far Ahead Of the Pack , New York Times, August 29, 1991
