Abstract: A harvester-thresher machine having a body flanked by a pair of hydraulic cylinders for tilting the body of the machine into an upright position in response to a tilt of the harvester-thresher, the cylinders being selectively connected to a source of pressurized liquid whose rate of flow is automatically adjusted in response to the degree of tilt of the machine.

Abstract: A device for the automatic adjustment of the position of the cutting platm of a grain-harvesting machine has a hydraulic cylinder attached both to a harvester body and to the cutting platform, the cylinder being supplied with oil under pressure from a pump by means of a differential distributor driven by feelers (sensors) mounted at the ends of the cutting platform.The differential distributor of the device, according to the invention is made up of a body provided with holes by means of which the distributor is connected to the pump to an oil tank and to the cylinder; inside the body, a casing and a plug are mounted. The casing is provided with holes which when the cutting platform is parallel with the soil register with holes in the plug which has a diametral channel, and with peripheral channels through which the oil passes when the cutting platform is not parallel to the soil.