Straw-walker combines cause high grain losses on hilly fields because the flow of crop onto the straw-walkers is impaired – resulting in higher grain losses uphill and downhill. Moreover, threshing crops such as e.g. maize require adapted straw-walker frequencies because the conveyor properties differ from those of grain straw. The Opti-Speed control system from New Holland alters the speed of the straw-walker shafts as a function of the slope inclination and the crop to be harvested.
The speed is reduced during uphill travel and increased on the downhill track. In both cases this results in a crop layer thickness similar to that achieved when harvesting on level ground. Accordingly, grain losses are reduced by comparison with a fixed straw-walker shaft speed. Furthermore, when selecting the combine settings for a different grain crop, the straw-walker shaft rpm matching this crop is loaded in the information system.
This adjustment and instrumentation control of the straw-walker shaft speed to the harvesting and working conditions is being shown for the first time and is therefore to be assessed as a significant further development in straw-walker combines.