Abstract: A liquid pump, in particular for liquids having a low viscosity, for example, water, alcohols or other chemical liquids is provided of the type which includes a gear unit or a gerotor mounted in a housing which has an inner gear driven by a shaft. The inner gear of the gear unit is mounted on a bushing, the width of which is determined by the required hydrostatic support forces in such a manner that the support faces lie directly in the plane of the hydraulic radial forces.

Abstract: A material straightening machine is provided with upper and lower roller frames and at least two piston assemblies interconnecting the frames and located respectively at the inlet and outlet sides of the roller frames. Each piston assembly includes a chamber housing a piston, the chamber being further divided by the piston into an upper annular chamber and a lower annular chamber. The upper annular chamber is connected directly to a pressure medium source while the lower annular chamber, which has a cross sectional area which differs from that of the upper annular chamber, is connected to the pressure medium source through a servo-controlled pressure reducing valve. Relative movement between the frames is effected by controlling the pressure reducing valve.