A hydraulic control valve unit includes an input port hydraulically coupled to a pump, a working port hydraulically coupled to the working load, and a return port connected to a hydraulic tank. The unit includes a control slide movable into different working positions in an axial direction for controlling a hydraulic flow between the hydraulic ports and a slide housing surrounding the control slide. The control slide includes a control segment which is delimited in the axial direction by a control edge, and cooperates with an axial housing segment of the slide housing for controlling a flow cross section for hydraulic flow at the control segment. The control slide is rotationally driven about an axis of rotation in a rotational direction. The control edge of the control segment or the housing segment cooperating with the control segment is designed such that the flow cross section has a different size depending on a rotational position of the control slide.

A first flow path area at a position where one of multiple openings of a sleeve and one of multiple grooves of a spool overlap with each other is different in size from a second flow path area at a position where another one of the openings of the sleeve and another one of the grooves of the spool overlap with each other. The one opening and the one groove form a flow path for connecting one of one pressure chamber and the other pressure chamber to a fluid supply source, due to displacement of the spool. The other opening and the other groove form a flow path for connecting another one of the other pressure chamber and the one pressure chamber to a fluid discharge port, due to the displacement of the spool.

A flow control valve includes a valve body having an inner circumferential surface defining a longitudinal bore to which first and second fluid passages are connected. A spool is slidably inserted into the bore to allow a flow of fluid from the first to second fluid passage. A valve regulates a flow rate of fluid flowing through the first fluid passage. A first seat surface is defined between an area in which the first fluid passage is connected to the bore and an area in which the second fluid passage is connected to the bore. When the flow of fluid from the first to second fluid passage is initiated, an area of a gap between the first seat surface and the spool on a plane taken in a transverse direction is 5%50%, preferably 10%20% of an area of an opening defined by the first seat surface.

An example valve includes: (i) a valve body defining a longitudinal cavity, where the valve body includes a supply inlet and an operating outlet; (ii) a cage disposed in the longitudinal cavity, where the cage includes (a) a first opening fluidly coupled to the supply outlet, and (b) a second opening fluidly coupled to the operating outlet; and (iii) a spool mounted within the cage and configured to move axially therein. When the valve is actuated, the spool moves within the cage to form a gap, thereby allowing pressurized fluid to flow from the supply inlet through the first opening, the gap, and the second opening to the operating outlet. A flow area defined around an exterior peripheral surface of the spool changes upstream from the gap at a first rate, and changes downstream from the gap at a second rate that is different from the first rate.

A control valve assembly for indirect pneumatic control and method for controlling a working fluid pressure, which enable precise, sensitive and speed-variable controlling. The assembly includes two valve units, a working fluid inlet, and a control fluid inlet. A working fluid channel connects the working fluid inlet through the two valve units to an outlet. A valve piston arranged within a valve cylinder of the valve units is movable between open and closed positions. A spring element biases the valve piston toward the closed position, and a control pressure chamber applies a control pressure counteracting the spring element's bias. When a control pressure is applied in the first chamber, the first valve piston is moved to the open position. Two opposite valve surfaces form a valve opening opened at varying widths when the valve piston is moved in the valve cylinder because of a changing control pressure, and the working pressure can be finely adjusted corresponding to the valve opening width depending on the control pressure.

The present disclosure provides: at least one component of a rotary valve subassembly; a rotary valve assembly including the rotary valve subassembly; a hydraulic circuit including the rotary valve assembly; an assembly including a robot that incorporates the hydraulic circuit; and a method of operating the rotary valve assembly. The at least one component of the rotary valve subassembly includes a spool. The at least one component of the rotary valve subassembly includes a sleeve.

Systems and methods are provided for enhanced valves. One embodiment is a hydraulic valve that includes a housing that defines a first port, a second port, and a third port for a hydraulic fluid, and a sleeve disposed within the housing that defines openings in fluid communication with the second port and the third port. The valve also includes a slide comprising a head and a shaft. The shaft is disposed within the sleeve and the slide is movable in a lengthwise direction from a closed position to an open position. The head includes a circumferential lip that extends perpendicular to the lengthwise direction, and that abuts the sleeve when the slide is in the closed position to prevent flow of the hydraulic fluid from the first port. The shaft provides a flow path between the second port and the third port when the slide is closed.

A slide for a fuel circuit valve of an aircraft engine extending along a longitudinal axis, and comprising a narrowed intermediate portion extending between two cylindrical end portions, a first end portion being separated from the narrowed intermediate portion by a shoulder having a surface arranged overall perpendicular to the longitudinal axis, the narrowed intermediate portion including in turn, as an extension of the shoulder, at least one cylindrical portion, the shoulder comprising at least one groove which extends radially from the cylindrical surface of the first end portion, towards the longitudinal axis, and which forms a fuel recirculation area which provides the generation of a jet of fuel on the cylindrical portion of the narrowed intermediate portion, when fuel flows along the first end portion towards the narrowed intermediate portion and the second end portion.

A spool for a fuel circuit valve of an aircraft engine, extending along a longitudinal axis and including a narrowed intermediate section extending between two end cylindrical sections, a first end section being separated from the narrowed intermediate section by a shoulder having a surface arranged overall perpendicular to the longitudinal axis, the narrowed intermediate section also including, extending away from the shoulder, at least one cylindrical portion, and the shoulder is provided with a step extending away from the cylindrical surface of the first end section which, when the fuel flows along the first end section towards the narrowed intermediate section and the second end portion, generates a jet of fuel on the cylindrical portion of the narrowed intermediate section, a recirculation of fuel forming in an area in front of the shoulder.

The invention relates to a valve comprising a valve housing (2) which, for transport of a heatable fluid such as hydraulic oil, has at least one utility connection (A, B), at least one pressure supply connection (P), and at least one return connection (T1, T2), and a control slide (6) which is guided in the valve housing (2) in a longitudinally displaceable manner. The valve is characterised in that, in at least one position of the control slide (6), in which position the pressure supply connection (P) is at least partially separated from the utility connection (A, B), the heatable fluid arrives, proceeding from this pressure supply connection (P) and via a heat-emitting connection in the control slide (6), at the at least one return connection (T1, T2) as a loss volume flow which, serving as a heat source, heats at least regions of the control slide (6).