Ground-working appliance, especially rotary harrow

摘要

The frame of the ground-working appliance (a rotary harrow is shown) is mounted on a three-point linkage of a tractor. One arm of an angle lever (10) mounted on the frame engages on the lower links of the three-point linkage of the tractor. A hydraulic cylinder (18) cooperating with a gas volume engages on the other angle-lever arm. When the working implements (32) strike an obstacle (S) the frame is pivoted in such a way that the working implements (32) move relative to the tractor in the opposite direction to the direction of travel of the latter. After the obstacle (S) has been overcome, the gas pressure in the gas accumulator generates a force in the hydraulic cylinder (18) which passes the frame back into the normal working position. The holding force of the hydraulic cylinder (18) is so high that a pivoting out of the normal working position occurs only when the forces on the working implements reach an intolerable amount. The device described ensures that the working implement (32) is protected against damage. IMAGE