Slide valve and a large two-stroke internal combustion engine

摘要

PCT No. PCT/DK93/00400 Sec. 371 Date Dec. 4, 1995 Sec. 102(e) Date Dec. 4, 1995 PCT Filed Dec. 2, 1993 PCT Pub. No. WO94/29578 PCT Pub. Date Dec. 22, 1994A 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). The movable part and the spool (38) are attached to each other so that the spool valve follows the movements of the movable part (56). The control unit (16) supplies current to the windings if the actual position of the movable part differs from the intended position.