PROJECT/HISTORY
The idea of combining the properties of rubber-tyred wheels and sprocket wheels or rolls is not new. Considerations and approaches already existed years ago, and we continued this with the acquisition of the Flexispike design.
Quality first: For successful series production, the first wheels were sold on the market as a "pre-series". At the same time, we were on the road with modified test wheels in wide-ranging field use. This was the method we used to continuously test, review, and evaluate.
We listened: The new Flexispike is based on feedback from test customers, end users, and sales partners, and our own findings from the field tests provide the finishing touch for us. In many practical applications with different conditions and circumstances, we have reviewed approaches and technical solutions. We have also simulated extreme conditions on stationary test facilities off-season.
The enhancements to the sprocket shape, arrangement, and tips; hub heads; and wheel mountings make the new Flexispike the best flexible wheel on the market.
PLASTIC SPROCKET
We have our well-known high standards for the production and assembly of the components for the ready-to-sell Flexispike.
For maximum durability, the moulded plastic sprockets are made of abrasion-resistant and very tough material. The special shape of the sprockets has clear advantages in practice.
SPROCKET TIP
Designed for durability and resistance, we have perfected the sprocket tips. By cold forming the tips and electroplating the surface, we achieve our ambitious goal. The sprocket is shaped as a special screw so that the sprocket unit can be attached to the tread using the same component.
FABRIC TUBE
The highest standards in terms of tear resistance, abrasion resistance and cold flexibility characterize the fabric tube. This is the tread of the wheel and consists of a multi-layer composite of various materials. By using load-bearing and non-load-bearing layers, we cross-link a three-dimensional, highly stable structure in the fabric tube. The components of natural rubber and styrene-butadiene rubber are therefore our method of choice. It prevents additional tearing if there are additional, external influences.
HUB HEAD
The pressed hub heads allow a maximum area of maximum flexing on the Flexispike. Various designs and hole patterns make it possible to mount on different wheel hubs and thus different carrier vehicles.
DESIGN AND USE/BENEFITS
The key feature of the Flexispike is certainly its maximum flexing characteristic. Up to now, flexing was only possible on a rubber-tyred wheel. For example, on a car. During the rolling process, the wheel deforms, resulting in a wider contact surface with the road surface and, in the event of obstacles or uneven surfaces, the wheel tread adapts itself accordingly. The sprocket wheels and rolls were unable to reproduce this effect.
For the Flexispike, the flexing properties have the advantage that the entire wheel width is not "lifted" when driving over an obstacle, stone, etc. Instead, a partial width of the wheel always remains in contact with the ground. Thus, the maximum number of sprockets for power transmission permanently engage in the ground.
Flexing also has advantages for the "climbing characteristics". For example, driving over curbs, border steps or difficult loading situations is made easier. Particularly loading situations.
SPROCKET GEOMETRY
Particular attention was paid to the sprocket shape itself. On the one hand, this is about the penetration of the sprocket into the ground. Its characteristic shape allows it to penetrate the ground easily, but it does not sink into the ground in soft conditions. On the other hand, when the wheel is rolling off the ground, it is a criterion that can be evaluated with as little damage to the scar as possible, since the shape of the sprocket also ensures this process optimally.
In addition to the plastic sprocket body, it is the steel sprocket that provides a unique grip. The shape of the steel tips ensures penetration – even in hard ground conditions. The plastic body is protected from heavy wear by the shoulder.
SPROCKET ARRANGEMENT
The arrangement of the sprockets seems trivial at first. However, we have tested various approaches and reviewed the effects for best customer benefit.
Where is the happy medium between sprockets placed far apart and sprockets placed close together? The single sprockets should be pressed securely into the ground – that is how optimal power is transmitted. At the same time, it must run as smoothly as possible on paved roads, hence the best level of comfort. In addition to the distribution in the row, the distribution of the rows is also important. We have developed a special pattern. By doing so, we can combine the aforementioned effects very well and give the Flexispike the highest practical suitability!
WIDE AND FLEXIBLE
The hub heads have only a narrow contact surface with the fabric tubes. Together with the row arrangements, this has little effect on the stiffness of the wheel. The wheel is open on the outside and inside, which does not limit flexing. Conversely, this means that flexing and damping properties are only possible to the maximum with the Flexispike.
The support in the wheel is arranged in such a way that the traction of both wheels is still ensured when travelling along contour lines. The physical relief of the upper wheel is optimised by the arrangement of the hub heads on the fabric tubes.
