Device and method for adjustment of sieve openings in a cleaning mechanism for a combine harvester

The present invention relates generally to agricultural machinery and, more particularly, to an apparatus and method for adjusting the sieve opening in the cleaning mechanism of a combine harvester. A device for adjusting the opening width of vibrating sieves in a cleaning mechanism of combine harvesters is arranged on and vibrates directly with the sieves or the sieve frame. The device includes an electric-motor-driven adjusting mechanism which actuates in a direction along an axis which differs from the direction in which the sieve is vibrating. A detector is activated when a particular sieve opening width is achieved. When the detector is activated, the particular opening width is associated with a position of the adjusting mechanism as measured by a position sensor, thereby allowing calibration of further adjustments to the sieve opening.