VERFAHREN UND VORRICHTUNG ZUM STEUERN EINES VORGANGES NACH EINER KONFIGURATION EINES FLAECHIGEN ODER RAEUMLICHEN GEBILDES NAHE DEM ERDBODEN

摘要

A support vehicle in the form of a tractor (16) carries a main fixed frame (8) on which is arranged an intermediate frame (7) the height of which can be adjusted by means of a cylinder (10). The intermediate frame supports, by means of two hydraulic cylinders (121) symmetrical about their common articulation (13), a support beam (5) on which are arranged, near each end, sensing devices (26) each with two staggered sensing contacts (21-24). Also arranged on the support beam (5) is a spraying device (6) with a row of spray nozzles (9) which spray a treatment fluid. Each pair of sensing contacts, (e.g. 23, 24, 211, 212), detects the height (c) of the support beam (5), and hence of the spray nozzles (9), above the ground (1) or envelope surface (4) of the crops (3). The measurement current, which flows through the plants and enters the ground, is drawn from the battery (18) of the vehicle, the negative terminal of which is earthed and the positive terminal of which is connected via the control unit (32) to the sensing contacts, which are connected by earth current circuits to the tyres (19). The more accurately the distance (b) above the crops (3) is maintained, the more uniform and hence the more efficient are the spraying operations.