Abstract: A servomotor composed of a servovalve controlling a hydraulic drum motor is disclosed. A housing is enclosed on the side of the inclined cylinder head by a cover serving as a bearing for the motor shaft, and on the side of the distribution ports by an enclosing plate serving as a second bearing for said shaft. The enclosing plate, having an essentially parallelopiped shape, includes two longitudinal boreholes disposed in parallel in a plane parallel to the plane of the plate, with each of said boreholes joining together a borehole perpendicular to the plate and opening into the use opening of the servovalve fastened to one of the surfaces of the plate, and another borehole perpendicular to the plate and opening into one of said distribution ports. The plate also includes at least one transversal borehole joining together the two longitudinal boreholes and containing two-way safety valves or their equivalent.

Abstract: A device for hydraulically lifting agricultural implements by a lifting jack, utilizing a pump with constant stroke volume and a stepless distributor. A flow pressure regulator of the pump is piloted by the pressure of the lifting jack, a downstroke valve is provided for lowering the implements, and a relay valve connects to the reservoir the piloting pressure of the regulator in the downward movement of the implements. A reducing valve fed by the flow circuit of the pump feeds at least one pilot electrovalve of the stepless distributor.

Abstract: Automatically controlling the transmission ratios of an automotive vehicle engine by detecting the speed of the engine, generating a signal proportional to the detected speed and comparing this signal with different predetermined reference speed signals, detecting the transmission ratio of the transmission, comparing this ratio with a predetermined reference ratio and generating a ratio signal as long as the detected ratio remains below the reference ratio, maintaining the detected ratio constant until the detected engine speed signal falls below the predetermined reference speed signal and generating a signal to increase the transmission ratio when the engine speed signal falls below the predetermined reference speed signal, and increasing the transmission ratio in the direction of the reference ratio as long as the detected speed signal remains below the predetermined reference speed signal and the detected ratio is less than the reference ratio.