Abstract: A operator supporting electrohydraulic drive and control system based on, position sensors (8) (9), a electronic control unite ECU (2), a recovery, storing and re-use system for energy, and with actuator (3) (4) and the drive control valve (6) (7) bolted together in one (3+6) (4+7) unite and with the valve (6) (7) independently of the ECU (2) is controlling effective use of pump capacity and recovery of energy and with control of speed for low speeds, or prevented speed by valves (6) (7) or pump (10) (10a) (11) (11a) displacement and for higher speed with control of deplacement of pumps and motors and with valves (6) (7) at the same time controlled to be fully open.

Abstract: An electrohydraulic governing system for governing system for governing at least movements of objects (3, 4) actuated by pressure fluid, one at the time or several simultaneously, which can receive or deliver energy, wherein the governing desires from an impulse generating guide means (1) via an electronic guide unit (2) are performed provided that this is possible in view of limitations in a pressure fluid source (5) delivering pressure fluid to the objects or provided this can be allowed in view of the strength, life and stability of the machine governed by the guide system or by the objects and as long as the functions operate and as long as the guide system or the guided machine is governed within limited secure field, wherein all the time the volume of the different parts or the sytem filled with pressure medium is measured directly or indirectly and upon governing of the pressure medium source and the valve means (8, 13, 15) connected to respective object it is governed so that the pressure fluid source

Abstract: A sealing device for sealing between two cylindrical members including a sealing ring and at least one other element arranged in a sealing groove in one of the members. The sealing ring is pre-stressed in its circumference and urged against the other member for dynamic sealing against this member and the other element is pre-stressedly arranged against the sealing ring for obtaining sealing between the sealing ring and the sealing groove. The sealing ring includes a substantially deformation stable, elastic and at least to a main part hard material providing a substantial, not deformed cross-section. Moreover, the sealing ring is thin having such a small radial middle height (h.sub.