Tyre pressure control systems offer many uncontested advantages, but also one drawback: they are very slow in inflating the tyres for road travel. Besides, they require the engine to be revving at high speeds to provide the necessary drive power for the compressor while the tractor is stationary. The Fend “VarioGrip Pro” uses an additional high-pressure tyre inside a bespoke and newly developed tyre. This internal tyre serves as an accumulator which allows the inflation pressure to be altered very quickly. The air is pumped into the internal tyre through a simple rotary union which also ensures it cannot escape. The valves involved and the pressure sensors are powered through inductive transmission inside the axle. The same applies to the control signals. Dispensing with extra compressors, pressure tanks and control lines, this technology is able to increase the inflation pressure from 0.8 bar to 1.8 within 30 seconds by exchanging the pressure directly and without having recourse to engine speed. This quick tyre pressure control system reduces the time spent in road travel and allows field work at low and soil-friendly pressures.
Fish living under the soil in an arid region