Hydraulic idling-regulating valve

The hydraulic idling-regulating valve means for controlling movements of a machine element drivable by a driving hydraulic cylinder means, the hydraulic idling-regulating valve means comprising at least one pair of mechanically operated through-flow valves arranged in a casing means and controllable by reciprocating movements of a valve actuating element to move from a neutral central position in which both valves are closed into alternative directions into a flow position and a closure position, an electromechanical specified-value setting system and a mechanical actual-value feedback system for at least one of setting and controlling specified and actual values of an instantaneous position of the pistons of the driving hydraulic cylinder means, the specified-value setting system comprising a hollow shaft rotatably mounted in a housing of the valve means and reciprocable in a longitudinal direction, said hollow shaft being rotatable through a number of revolutions correlated with the respective specified value by an electric motor provided for the purpose of controlling the specified value, said actual-value feedback device comprising a feedback spindle engageable through an external thread, with an internal thread of the hollow shaft and coupled by form-locking means to move with the piston of the driving hydraulic cylinder means either, when a connection with the piston is rigid, in a manner that the feedback spindle follows any displacement of the piston or, in the case of a rotational connection with the piston, in a manner that the feedback spindle performs a number of revolutions correlated with the movements of the piston, in which case the valve-actuating elements are subjected to the same displacements in the axial direction as the hollow shaft, the hollow shaft being rotatably supported in the value-actuating element which is secured against rotation in the casing, said casing includes a circular cylindrical core with at least one first longitudinal bore and/or in which the longitudinally movable pistons of the at least one pair of throughflow valves are longitudinally movable between stop elements fixed against rotation relative to the casing means, movable in the longitudinal direction, and another bore in which the hollow shaft of the specified-value setting system is mounted, said stop elements being carried axially and radially on said hollow shaft through pivot pads, said casing means further comprising a cylindrical circular envelope into which the circular cylindrical core is firmly set, connections spaces on a pressure-source side and a consumer side which, depending upon a position of the valve pistons are either connected to communicate with each other or are closed with respect to each other, said connection spaces being defined by external grooves on the circular cylindrical core and by inner surface areas of the envelope fixed thereto, and wherein inlet and outlet ducts are defined by radial bores in the circular cylindrical core and the cylindrical circular envelope.