Four or more cultivator arms or shanks are pivoted to the front and rear of a main frame and are interconnected by linkage so that if a cultivator blade on one arm strikes an obstruction, then it moves rearwardly to clear same and at the same time the others that are interconnected, move forwardly by a lesser amount thus absorbing the movement of the cultivator blade striking the obstruction. When the obstruction is passed, the engagement of the remaining blades with the ground, returns them to the original position thus returning the tripped blade to the original position.
A soil cultivating machine has a beamed frame, and working members arranged in pairs. Two working members are mounted one behind the other, preferably on a common carrier beam which is releasably secured to transverse beams of the frame. Thus the two working members and the carrier beam constitute a working unit which is readily releasable from the frame. The two working members of the pair are interlinked by a connecting rod to ensure a uniform operating depth over irregular ground and the members can be located on opposite sides of the carrier beam as viewed in plan. In one embodiment, the working members are mounted on pivot pins journalled to different frame beams and the members are arranged in rows that are inclined to the direction of travel. The beams with working members can be arranged in groups that are hinged to one another for elevation to a reduced transport position. A wheeled central frame portion has an intermediate frame portion and an outer frame portion to each side which are linked to a respective swingable arm. The arm can be turned by a hydraulic ram so that, first, the outer portion is raised and then the intermediate portion is elevated above the central portion.
