Abstract: The present invention pertains to a dual-function hydraulic valve (1), i.e., a control valve and a pressure reduction or limitation valve at the same time. The inventive combined hydraulic valve (1) encompasses a valve casing (2) with a first central pressure connection (P), a second central pressure connection (Br) and a movable flow check piston (7) in the valve casing (2). The flow check piston (7) presents a pressure surface (16) enabling it (P), when the first central connection is put under supply pressure (P.sub.p), to move from its basic position against an opposing force proportional to said supply pressure (P.sub.p) It also presents a first control ridge (40) and a second control ridge (41). The first control ridge (40) is used to link the first central pressure connection (P) to the second central pressure connection (Br), starting from a first set minimum displacement of the flow check piston (7) which corresponds to a lower threshold value (P.sub.1) of the supply pressure (P.sub.p).

Abstract: The invention relates to a hydrostatic machine, in particular axial piston machine, having a machine housing the internal housing chamber of which accommodates a drive mechanism rotatably mounted by means of at least one bearing and has a leakage oil chamber opening to the outside via at least one leakage oil connection. To avoid splash losses of the hydrostatic machine, in accordance with the invention a pump device (29; 50; 60; 70) is arranged in the internal housing chamber in driving connection with the drive mechanism (3, 4, 7), which device is provided to pump leakage oil out of the leakage oil chamber (28) through the leakage oil connection (8, 37; 72) to the outside.

Abstract: A hydrostatic machine which includes a housing having an internal space accommodating a rotatably journaled driving mechanism, and wherein the portion of the internal space which is not occupied by the driving mechanism encompasses a drain oil chamber which receives the drain oil inclusive of lubricating oil which is discharged from bearing locations of the hydrostatic machine, and which is connected or port to a tank through at least one drain oil connection of the housing and through a drain oil line.

Abstract: The invention relates to a power control device for two variable displacement pumps, each with an adjusting device which can be acted upon by adjusting pressure, a power control valve associated therewith, which is acted upon by a first control pressure corresponding with the operating pressure of the variable displacement pump to be adjusted against a pressure difference in the direction of the control position, in which the adjusting pressure loading is controlled in the direction of reduced displacement of the variable displacement pumps along a hyperbolic control curve, whereby the pressure difference results from a spring-arrangement backpressure counteracting the first control pressure and a second control pressure corresponding with the operating pressure of the other variable displacement pump and with increase of the same drops from a maximum value to a minimum value.