A pressure relief valve for a fluid power assist steering system. The valve includes a housing and a spool disposed in the housing. The spool defines a cavity and has a first end and a second end. The spool is movable in the housing to limit an output pressure of the pump. A poppet seat is secured to the second end of the spool. A poppet is disposed in the cavity. A poppet spring biases the poppet into engagement with the poppet seat. A set screw is received in the first end of the spool. The set screw is rotatable relative to the spool to adjust a compression level of the poppet spring.

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.

A spool 220 is provided with a second land section 224 that blocks a portion between the spool 220 and the valve sleeve 210 at a position between the output port P21 and the lead-in port P22 when the spool 220 is located in a position for connecting the channel for input T1 and the channel for output T2 via the input port P10 and the output port P21 and blocking a channel leading from the channel for output T2 to the channel for discharge T3, and when the spool 220 is located in a position for connecting the channel for output T2 and the channel for discharge T3 via the lead-in port P22 and the discharge port P30 and blocking a channel leading from the channel for input T1 to the channel for output T2.

A valve includes a basic body, control spool, sealing ring, and control cover. The control spool is received in the basic body to be movable along a longitudinal axis. The basic body includes a counter-sealing surface, connecting channel, and tank channel having at least one first annular groove surrounding the control spool. The control cover and at least one end face of the control spool facing toward the longitudinal axis delimits, at least in part, a control space. The control cover includes a sealing surface that abuts the counter-sealing surface of the basic body. At least one of the sealing surface and the counter-sealing surface includes a sealing groove that surrounds the control space in ring-like fashion. The sealing ring is received in the sealing groove. The connecting channel opens out into the tank channel and into the sealing groove.

A spool for a hydraulic valve includes a cylindrical body having a first end, a second end disposed opposite the first end, and an annular wall defined by an internal surface of the cylindrical body and an external surface of the cylindrical body. The annular wall defines a plurality of holes therethrough. The internal surface defines a first chamber, a second chamber, and a slot chamber within the cylindrical body, the second chamber being in fluid communication with the plurality of holes via the first chamber, the slot chamber being located between the second chamber and the second end of the cylindrical body. The annular wall defines a slot therethrough, the slot extending from the second end of the cylindrical body toward the first end of the cylindrical body along the longitudinal direction, the slot being open at the second end of the cylindrical body along the longitudinal direction.

An electrohydraulic control valve (1) comprising a control valve element (2) displaceable in a first direction by a pressure in a first pressure chamber (5) and in a second direction by a pressure in a second pressure chamber (6). Each pressure chamber (5, 6) is connected to a line between a high pressure port (PP) and a low pressure port (PT) via a magnetic valve (11, 12). Each magnetic valve (11, 12) is a three-way valve and comprises a first valve seat (17) and a second valve seat (18). A space (19) between the first valve seat (17) and the second valve seat (18) is connected to the pressure chamber (5, 6) and a first valve element (20) positioned outside the space (19) cooperates with the first valve seat (17) and a second valve element (21) positioned outside the space (19) cooperates with the second valve seat (18).

A spool component for use in a spool valve has a cylindrical body including a first diameter portion and a second diameter portion, the first diameter portion having a diameter that is larger than a diameter of the second diameter portion. A metering notch is cut into the first diameter portion and extends toward the second diameter portion. The metering notch includes a first angle cut and a second angle cut that are sloped at different depth angles toward the first diameter portion. A spool valve assembly includes a housing defining a bore, and the spool component, which is moveable within the bore along a stroke distance comprising a metering band for metering a flow of fluid across the spool component. The metering notch provides precise metering of the flow of fluid across the spool component based on the different depth angles of the cuts in the metering notch.

A spool for a spool valve having a longitudinal axis (L). The spool comprising: a plurality of lands each having a substantially radially extending metering edge and an axially extending circumferential surface; a plurality of grooves separating each of the plurality of the lands; and a guiding section located axially between at least one land and an adjacent groove. The guiding section comprising a plurality of circumferentially spaced guiding surfaces being substantially flush and contiguous with the circumferential surface of the land, wherein the guiding section allows fluid communication between the groove and the metering edge of the land.

A control valve device includes a valve body having an actuator port connected to an actuator and a relief passage configured to allow the actuator port to communicate with a return passage, a spool slidably assembled into the valve body and configured to allow the actuator port to selectively communicate with a supply side or a return side, a relief valve configured to open/close the relief passage to control pressure of the actuator port, and an on/off valve assembled into an assembling hole which is formed in the valve body. The on/off valve configured to allow the actuator port to communicate with the relief passage through the assembling hole at the time of valve open.