Abstract: In an oil supply device for a machine having different categories of oil consumers, to which respectively one supply loop provided with at least one pump is provided, it is possible to achieve a simple structure and advantageous operating costs in that all supply loops can be provided with oil from a common oil tank, that at least one supply loop having a self-cleaning filter provided with an outlet for oil sludge, and that a separating device is provided, which can be charged at least with the oil sludge from each self-cleaning filter and which has a clean oil outlet terminating in the oil tank.

Abstract: A spool valve (22) controls a hydraulic drive, such as a drive for a fuel pump (18) in an internal combustion engine, in which the hydraulic drive comprises a driving piston (34) journalled in a hydraulic cylinder (33) which through a flow passage (31) is in communication with the spool valve. The spool (38) may occupy a position in which the flow passage is connected with a high-pressure source (29) and another position in which the flow passage is connected with a low-pressure port (30). The spool is settable by means of a positioning means (23) electrically activated by a control unit (16) which determines intended positions of the spool and for a movable part (56) in the positioning member. The movable part has windings (51) positioned in a magnetic field in a slit (60) which is oblong in the longitudinal direction of the spool. A sensor (66) signalizes the actual position of the movable part to the control unit (16).

Abstract: An internal combustion engine (1) has hydraulically driven exhaust valves (13) and fuel pumps (18). The hydraulic drives are controlled by means of a computer (16) and electrically activated positioning means (64) setting a spool in a spool valve. If the electronic control of the engine fails, the spool movement may be controlled by a first piston (41) on which the pressure in a hydraulic hose or conduit (48) acts, said conduit extending to a second piston (44) which may follow a cam (26) on a rotating camshaft. The hydraulically driven cylinder members (13, 14, 18) associated with each of the engine cylinders are mounted at the pertaining cylinder, whereas the camshaft (23) independently of the positioning of the cylinder members is disposed at an appropriate shaft drive, such as the crankshaft (11). The cam shaft has a very short length and small mass and may for instance be disposed at one end of the engine.