Multi-outlet regulating valve

Abstract

A dual-outlet and dual discharge pressure regulating valve (200) comprises a three-way cylinder (210) forming a cylindrical chamber (211) having an axial inlet path (240) and two radial outlet paths (251, 252). It comprises a fluidtight cylindrical piston (220) sliding inside the cylindrical chamber under the combined action of the inlet pressure (P) and of a return spring (230) calibrated for two discharge pressures. A first discharge pressure (P1) causes the piston to assume a first position opening a first flow path between the inlet path (240) and a first outlet path (251). A second discharge pressure (P2) causes the piston to assume a second position opening a second flow path between the inlet path and a second outlet path (252), in addition to the first flow path.

Description

[0001] DESCRIPTION

[0002] TITLE: MULTI-OUTLET REGULATING VALVE

[0003] technical field

[0004] The present invention relates to hydraulic and pneumatic components, and more particularly to a regulating or relief valve which can be fitted to a fluidic circuit of an aircraft engine.

[0005] Previous techniques

[0006] The operation of an aircraft engine requires a large number of accessories, such as generators, fuel and lubricating oil pumps, air compressors, hydraulic pumps and starters.

[0007] Typically, the size of these accessories tends to increase, for example due to larger generators designed to meet higher power consumption. This increased size complicates the integration of the accessories.

[0008] At the same time, the available volume in engine compartments for installing these accessories tends to decrease with newer engine generations. This reduction in volume generally stems from a quest to optimize aerodynamic lines and improve engine efficiency. In particular, some engine architectures require accessories to be positioned in the core area, where available space is even more limited.

[0009] Therefore, there is a need to reduce the size of accessories in an aircraft engine.

[0010] A typical accessory is the "lubrication group".

[0011] Aircraft engines of the turbojet, turbofan, or turboprop type contain numerous moving mechanical parts, such as bearings, gears, and squeeze films (compressed fluid films), which require lubrication, typically with oil. This oil is distributed within a lubrication system or circuit by a piece of equipment called a "lubrication unit," which is installed on an accessory gearbox (AGB).

[0012] This equipment contains various valves that allow the regulation and protection of the oil circuit by discharge.

[0013] Figure 1 illustrates an example of a 100 hydraulic circuit with regulating valves.

[0014] The hydraulic circuit 100 includes a liquid supply 1 10, here oil, downstream of a line connected to a reservoir (not shown) and equipped with an ALV anti-drainage valve (for "anti-leakage valve").

[0015] The supply outlet line 1 10 feeds a FILT filter which supplies one or more lines to the mechanical parts to be lubricated, via a non-return valve NRV (for "non return valve").

[0016] The supply outlet line 1 10 is also common to a first By-pass bypass valve and a second PRV relief valve (for "pressure relief valve").

[0017] The bypass valve allows opening or closing a bypass / shunt circuit from the FILT filter to the NRV check valve, particularly in the event of filter clogging. Clogging can, for example, correspond to a pressure drop exceeding a threshold AP between the two sides of a FILT filter. The bypass valve is typically designed or calibrated with a discharge pressure equal to AP.

[0018] The PRV relief valve (for "pressure relief valve") provides protection of the circuit against overpressures, by returning excess oil to the reservoir or to a recovery circuit (for example to the inlet of a recovery pump present in the lubrication group).

[0019] The PRV relief valve is generally designed or calibrated with a higher discharge pressure than the By-pass valve.

[0020] These valves, although performing different functions within the hydraulic circuit, are identical components (valves) located at different points in the circuit. A control valve comprises a multi-way chamber – an inlet and an outlet – generally formed by a cylinder, and a sealed piston sliding inside the chamber under the combined (and opposing) action of an inlet pressure in the inlet and a return element.

[0021] In general, in hydraulic and pneumatic circuits, several relief valves can be installed on the same inlet line to regulate or protect the circuit. These valves have a common inlet but different discharge destinations and may or may not have different discharge pressures.

[0022] This material duplication results in additional mass and volume, which is detrimental to the compactness or reduction of the size of the accessories.

[0023] There is therefore a need to improve the size of hydraulic or pneumatic components, in particular regulating or relief valves equipping a fluidic circuit of an aircraft engine.

[0024] Description of the invention

[0025] The invention aims to overcome at least some of the aforementioned drawbacks and to provide a regulating or relief valve with multiple outlets and multiple respective relief pressures. This allows several valves sharing the same inlet pipe to be combined into a single component within the hydraulic or pneumatic circuit. This results in a reduction in compactness and weight. Furthermore, the internal pipework within the circuit is simplified.

[0026] In view of the foregoing, one aspect of the invention relates to a fluidic control valve for an aircraft turbomachine fluidic circuit, said valve comprising a multi-way chamber, including an inlet channel, and a sealed piston assembly sliding inside the chamber under the joint (or combined) action of an inlet pressure in the inlet channel and a return element, valve in which the chamber comprises a plurality of outlet channels and the piston assembly is configured to take different positions in the chamber as a function of several inlet pressures, respectively opening different circulation channels between the inlet channel and the different outlet channels.

[0027] As explained later, the number of output channels is not fixed, and can depend on the desired application: two outputs for a double-output control valve, three for a triple-output control valve, etc.

[0028] The valve according to the invention thus has a staged operation: when the piston moves from one position to the next, a new exit route is activated, that is to say, a new circulation route to this new exit route is opened.

[0029] Such a valve thus makes it possible to merge two (or more) relief valves into a single component ensuring the two initial functions, regardless of the destination of the discharges and the discharge pressures.

[0030] In particular, the piston assembly takes, with a first inlet pressure, a first position opening a first circulation path between the inlet path and a first outlet path and takes, with a second inlet pressure, a second position opening a second circulation path between the inlet path and a second outlet path.

[0031] Given the progressive sliding of the tracking assembly, the first or second input pressure can here be understood as a pressure belonging to a first or second pressure range, respectively.

[0032] An nth position of the piston at an nth inlet pressure can also define an nth flow path between the inlet path and the nth outlet path.

[0033] The valve according to the invention is of particular interest when its outlets are connected to a circuit or equipment which provides a back pressure or when its outlets are equipped with flow or pressure limiters / restrictors downstream.

[0034] In one embodiment, the flow paths accumulate with the advancement of the piston assembly's positions within the chamber. This cumulative effect notably allows for configurations that replace two valves operating simultaneously at two different discharge pressures, for example, the By-pass and PRV valves of an aircraft engine lubrication system.

[0035] Alternatively, two flow paths are mutually exclusive (one from the other) between two positions taken by the piston assembly in the chamber. Thus, the valve, depending on the inlet pressure, can alternately distribute the fluid to one or the other of the corresponding outlet paths.

[0036] In one embodiment, the piston assembly consists of a single piston actuated by a return spring. Such a valve is compact and offers reduced manufacturing complexity.

[0037] In an alternative embodiment, the piston assembly comprises two pistons actuated by their respective return springs. Such a valve can be used in certain configurations imposed by the integration environment, for example, when the input channel is located between two output channels.

[0038] In one embodiment, the piston assembly comprises a piston that is substantially cylindrical in shape. The chamber is therefore cylindrical, and the piston typically has dimensions complementary to the cylindrical chamber formed by the cylinder.

[0039] In yet another alternative embodiment, the piston assembly comprises a ball-shaped (or spherical) piston. Here again, the chamber is preferably cylindrical to allow the ball to slide.

[0040] Conventional piston sealing elements (e.g., gaskets) can be provided where necessary.

[0041] In one embodiment, the chamber is formed from a single cylindrical chamber.

[0042] In an alternative embodiment, the chamber is formed of several (typically two) coaxial cylindrical sub-chambers of different diameters, communicating with each other and each having at least one exit channel.

[0043] According to a particular feature, the piston assembly comprises a piston made up of several coaxial cylinders configured to slide respectively in several cylindrical sub-chambers. The use of a sealed piston with two (or more) diameters advantageously allows the activation of two outlets in two adjoining chambers of very distinct volumes, which generate widely separated discharge pressures.

[0044] In yet another alternative embodiment, the chamber is formed of several cylindrical sub-chambers arranged in a star shape around the inlet channel, each cylindrical sub-chamber having its own sealed piston sliding inside it under the combined action of the inlet pressure in the inlet channel and a respective return element.

[0045] In one embodiment, the inlet channel is arranged axially at one end of a cylindrical portion of the chamber.

[0046] In an alternative embodiment, the inlet port is arranged radially from a cylindrical portion of the chamber. This configuration is particularly suitable for a valve with two pistons, the inlet port then opening between the two pistons in a rest position.

[0047] In one embodiment, the outlet ports are arranged radially from a cylindrical portion of the chamber. More generally, the outlet ports can be lateral to the axis of piston movement within the chamber.

[0048] According to a particular embodiment, two radial outlet paths are arranged at the same height of the cylindrical part of the chamber, thus satisfying any possible constraints on the integration of the valve.

[0049] In an alternative embodiment, an outlet channel is arranged axially at one end of a cylindrical portion of the chamber, usually the end opposite to that located near the inlet channel.

[0050] In one particular embodiment, the chamber includes a bypass zone (e.g., a bulge) external to the cylindrical portion in which a piston slides. The bypass zone extends between two bypass orifice zones of the cylindrical portion, separated by a distance greater than the axial length of the piston (in its sealing zone). This arrangement allows, when the piston reaches the position between the two bypass orifice zones, the activation / opening of a lateral flow channel to an outlet located on the opposite side of the piston, typically an opposite axial outlet.

[0051] In one embodiment, the piston assembly comprises a piston having a channel extending from a face of the piston opposite the inlet channel and a lateral face of the piston.

[0052] In a configuration with lateral / radial outlet channels at the same height, this arrangement allows for the activation of two outlet channels with different inlet pressures. A greater number of channels can be provided, opening at different heights on the lateral face(s), to activate a greater number of outlet channels arranged axially at the same height within the chamber.

[0053] In a configuration with two radial / lateral output channels placed at different heights in the chamber, this arrangement allows one or the other of the output channels to be activated alternately.

[0054] In particular, the piston has an axial length such that when the channel is opposite a second outlet, a lateral wall of the piston obstructs a first outlet.

[0055] When there are more than two exit routes, the choice of piston length allows the first and second exit routes to be blocked when the channel is opposite a third exit route, or alternatively only the second exit route to be blocked, so as to allow a cumulative flow of traffic through the first and third exit routes.

[0056] A particular application of the valve according to the invention is the sharing of the By-pass and PRV valves of Figure 1.A preferred regulating valve is of the double outlet and double discharge pressure type, comprising a three-way cylinder forming a cylindrical chamber having one axial inlet and two radial outlets positioned at two different heights along an axis of the cylinder, and comprising a cylindrical sealed piston sliding inside the cylindrical chamber under the combined action of the inlet pressure in the inlet and a return spring calibrated according to two discharge pressures, a first discharge pressure causing the piston to take a first position opening a first flow path between the inlet and a first outlet, and a second discharge pressure causing the piston to take a second position opening a second flow path between the inlet and a second outlet, in addition to the first flow path.

[0057] Another aspect of the invention relates to an aircraft turbomachine, comprising a fluidic circuit including at least one regulating valve as defined above.

[0058] A second aspect of the invention relates to a method for operating a hydraulic or pneumatic circuit comprising:

[0059] The injection of a fluid into an inlet of a control valve comprising a multi-way chamber within which a sealed piston assembly slides under the combined action of the pressure of the inlet fluid and a return element, a method in which, when the pressure of the inlet fluid takes different values, the piston assembly takes different positions in the chamber, opening respectively different circulation paths between the inlet and different outlet paths of the chamber.

[0060] Brief description of the drawings

[0061] The invention will be better understood upon a detailed study of two embodiments taken by way of non-limiting examples and illustrated by the accompanying drawings, in which:

[0062] [Fig 1] illustrates an example of a hydraulic circuit with regulating valves according to the prior art;

[0063] [Fig 2] illustrates the hydraulic circuit of Figure 1 in which the By-pass and PRV control valves are replaced by a single component multi-outlet double valve according to one embodiment;

[0064] [Fig 3] illustrates a first embodiment of a multi-outlet control valve;

[0065] [Fig 4] illustrates a second embodiment of a multi-outlet control valve; [Fig 5] illustrates a third embodiment of a multi-outlet control valve;

[0066] [Fig 6] illustrates a fourth embodiment of a multi-outlet control valve;

[0067] [Fig 7] illustrates a fifth embodiment of a multi-outlet control valve;

[0068] [Fig 8] illustrates a sixth embodiment of a multi-outlet control valve;

[0069] [Fig 9] illustrates a seventh embodiment of a multi-outlet control valve;

[0070] [Fig 10] illustrates an eighth embodiment of a multi-outlet control valve; and

[0071] [Fig 1 1 ] illustrates a ninth embodiment of a multi-outlet control valve.

[0072] For clarity, the same elements are designated by the same reference numerals in the different figures. Furthermore, the various figures are not drawn to scale, as is customary in a schematic representation of a hydraulic or pneumatic component.

[0073] Detailed description

[0074] Figure 2 illustrates the hydraulic circuit 100 of Figure 1 in which the By-pass and PRV control valves are replaced by a single multi-outlet valve component 200, here with two outlets.

[0075] As schematically represented by several springs, the 200 multi-outlet valve has several discharge pressures which successively activate several outlets of the valve, and thus discharge the fluid onto one or more different pipes.

[0076] According to the invention, the regulating valve 200 comprises a chamber (typically formed by a cylinder, but not exclusively) with multiple ports, including one inlet port and several outlet ports. The valve also includes a sealed piston assembly (typically a cylindrical piston, but not exclusively) sliding within the chamber under the combined action of the inlet pressure at the inlet port and a return element, typically a calibrated return spring. Depending on the inlet pressure, the piston assembly assumes different positions within the chamber, each position activating a different outlet port, i.e., opening a new respective flow path between the inlet port and the different outlet port.

[0077] For illustrative purposes, the piston(s) slide within cylindrical chambers in the following description, although it is possible to have pistons with different cross-sections complementary to an internal chamber cross-section, for example, in the shape of regular polygons. The return elements are typically return springs, which are referred to as such in the following description. For this purpose, the term "return spring" hereafter refers to a single return spring, a set of parallel springs (coaxial or not), or springs connected in series to form a general return spring.

[0078] Similarly, the outlet ports are usually shown on the same side of the valve chamber to simplify illustrations. However, the outlet ports can be arranged on opposite sides of the chamber, and generally according to different angular coordinates (or azimuths) in a plane perpendicular to the main axis of the chamber (along which the piston slides).

[0079] The set of parts illustrated below, forming the 200 valve, can be made of a metal, such as aluminum.

[0080] Figures 3 to 9 illustrate multi-outlet control valves 200 formed from a single cylinder 210 and therefore a single cylindrical chamber 21 1.

[0081] In the embodiments illustrated by Figures 3 to 5, the piston assembly comprises a single cylindrical piston 220, and the output ports are cumulative.

[0082] In this operation, the flow paths created by the advancement of the piston 220 in the cylindrical chamber 211 are cumulative. In other words, when the inlet pressure increases, the piston moves from a rest position where no outlet is connected to the inlet, to a first operational position activating a first outlet, i.e., opening a first flow path between the inlet and the first outlet. Then, when the piston reaches a second inlet pressure, a second operational position under the effect of a second inlet pressure greater than the first, a second outlet is activated, i.e., opening a second flow path between the inlet and the second outlet.In this cumulative mode, this second traffic lane is additional to the first traffic lane: in the second operational position, the fluid is evacuated through the first and second exit lanes, whereas in the first operational position, the fluid is evacuated through only the first exit lane.

[0083] To simplify the explanation, the following primarily describes double-outlet control valves. However, those skilled in the art can apply the principles outlined below to a larger number of outlets, typically up to ten outlets.

[0084] Figure 3 illustrates a first embodiment of a multi-outlet control valve 200 comprising a cylinder 210 defining a cylindrical chamber 211, a piston 220 and a return spring 230.

[0085] The chamber 211 has an axial inlet 240 disposed at one end 212 of the chamber and two radial outlet 251, 252 disposed at two different heights along the axis A of the cylinder 210.

[0086] The piston 220 is cylindrical in shape with a diameter equal to that of the chamber 211 so as to slide, in a sealed manner, within the chamber. A front surface 221 of the piston 220 is in contact with the fluid at the inlet 240 of the valve, while a rear surface 222 of the piston 220 is stressed by the return spring 230, the latter bearing against the bottom of the cylinder, formed by the end 213 opposite that 212 of the inlet channel 240.

[0087] In the rest position (low or zero inlet pressure PO), the piston 210 obstructs the inlet channel 240 by the effect of the spring 230 (left configuration).

[0088] The return spring 230 is calibrated so as to position the cylindrical piston 220 in a first operational position (middle configuration) when the inlet fluid pressure 240 reaches a first discharge pressure PI, and to position the cylindrical piston 220 in a second operational position (right configuration) when the inlet fluid pressure 240 reaches a second discharge pressure P2 greater than the first discharge pressure PI.

[0089] In the first position of the piston, a channel or fluid circulation path (doubled arrow) is created between the inlet area 240 and the first outlet path 251. In the second position of the piston, a second fluid circulation path between the inlet area 240 and the second outlet path 252 is added to the first circulation path (two doubled arrows).

[0090] Note that when the inlet pressure is between P1 and P2, the first outlet is open, allowing the fluid to be discharged. Valve 200 is therefore open.

[0091] Such a 200 valve is therefore particularly suitable for replacing the By-pass and PRV valves of the lubrication circuit in Figure 1.

[0092] As an alternative to using a cylindrical piston, the 220 piston can take the form of a ball or sphere (as illustrated for example below in relation to Figure 9).

[0093] Figure 4 illustrates a second embodiment of a multi-outlet control valve 200.

[0094] Figure 4 differs from Figure 3 in that the second output channel 252 (more generally the last output channel) is not radial but axial, arranged on the end 213 (the bottom) of the cylinder 210.

[0095] To allow the creation of the second flow path (piston in second position – right-hand configuration), chamber 211 includes a bypass zone 260 external to the cylindrical portion in which piston 220 slides. This bypass zone extends between two bypass orifice zones 01 and 02 of the cylindrical chamber. Zones 01 and 02 are separated by a distance D greater than the axial length 'd' of piston 220. Zones 01 and 02 may correspond to two separate orifices (not shown) or to opposite zones of the same orifice or opening in the cylinder wall (as shown in the Figure). The bypass zone 260 may be formed by a cover welded to an external wall of cylinder 210, by a conduit welded to orifices 01 and 02, or by a channel formed in a housing defining chamber 211.The 260 derivation zone is preferentially formed on only an angular portion of the cylinder, typically less than 7i / 4.

[0096] Again, as shown in the Figure, in the first piston position (middle configuration), a fluid circulation path is created between the inlet zone 240 and the first outlet 251. In the second piston position (right configuration), a second fluid circulation path between the inlet zone 240 and the second outlet 252, via the bypass zone 260, is added to the first circulation path.

[0097] Figure 5 illustrates a third embodiment of a multi-outlet control valve 200.

[0098] Figure 5 differs from Figure 3 and Figure 4 in that the two radial outlet paths 251, 252 are arranged at the same height of the cylindrical chamber 211.

[0099] To allow the creation of the first flow path (piston in the first position – middle configuration), the piston 220 includes a channel 223 extending from the face 221 of the piston opposite the inlet passage 240 and the lateral face of the piston. The channel 223 can be formed by drilling through a solid cylinder.

[0100] As shown in the Figure, in the rest position (left configuration), the piston 220 tightly blocks the inlet channel 240, the lateral outlet of the channel 223 not opening onto any of the outlet channels.

[0101] Again, in the first position of piston 220, only one outlet is activated: a single fluid circulation path is created between the inlet area 240 and the first outlet path 251, via channel 223 whose lateral outlet opens onto the outlet path 251. At the same time, piston 220 obstructs the second outlet path 252.

[0102] In the second position of the piston, a second outlet is activated in parallel: the movement of the piston 220 simultaneously opens the two outlet channels 251 and 252, allowing the simultaneous creation of the two flow paths to these two outlets. Depending on the dimensions involved and the piston's advance, the channel 223 can continue to contribute to the first fluid flow path, or its lateral outlet can open onto the inner wall of the cylindrical chamber 211 just above the first outlet zone 251 (as illustrated in the configuration on the right), thus blocking said channel 223.

[0103] In the embodiment illustrated by Figure 6, the outlet paths are alternative. This means that at the two (or more) operating positions, different and mutually exclusive fluid flow paths are open, one via the first outlet zone 251, the other via the second outlet zone 252.

[0104] The embodiment shown in Figure 6 is similar to that of Figure 3, in which the cylindrical piston 220 includes a channel 223 extending from the face 221 of the piston opposite the inlet port 240 to a lateral face of the piston. This channel 223 creates a first fluid flow path when the piston 220 is in the first position (mid-position configuration) corresponding to an inlet pressure PI.

[0105] The axial length (along axis A - the height in the Figure) of the cylindrical piston 220 between the lateral outlet of the channel 223 and the front face 221 is such that when the channel 223 is opposite the second outlet 252 (piston in the second position - right-hand configuration), the lateral wall of the piston obstructs the first outlet 251. Thus, the second flow path is created between the inlet 240 and the second outlet 252 while closing the first flow path between the inlet 240 and the first outlet 251. The flow paths are alternative.

[0106] Note that when the inlet pressure is located between PI and P2 (generally between the inlet ranges where the lateral outlet of channel 223 faces one or the other of the outlet paths 251, 252), the valve is closed because the outlet paths are blocked by the piston 220 (the lateral outlet of channel 223 being located between the two outlets).

[0107] In the example in the Figure, the piston 220 further includes, on the side of its face 221, a recessed area 224 coaxial over a large proportion of the diameter of the piston 200. The channel 223 can thus be formed by the recessed area 224 and then by a portion of channel from the bottom of this recessed area to a lateral face of the piston 220. This recess 224 makes it possible to reduce the weight of the piston 220 (and therefore of the valve 200) while maintaining a piston of axial length 'd' (via the wall 225 maintained by the recess) to block the first outlet 251 in the second operational position.

[0108] The recess 224 may be omitted in which case a narrower channel 223 is provided between the front face 221 of the piston and a lateral face thereof.

[0109] Although the configurations in Figures 3 to 6 illustrate an axial inlet 240 of the cylindrical chamber, it may be provided that the inlet 240 opens laterally / radially near the end 212 of the chamber 210. In this case, a stop may be provided in the chamber to prevent the piston 220 from blocking the inlet 240 and to allow the inlet fluid to come into contact with the surface 221 of the piston.

[0110] Furthermore, although only one inlet 240 is shown, this can be formed from several orifices coming from the same pipe or from several separate pipes.

[0111] Figure 7 illustrates an embodiment of a triple outlet control valve 200, using the piston 220 of Figure 6. The following description relating to the three outlets nevertheless also applies to the valves of Figures 3 to 5. In particular, three lateral / radial outlets 251, 252, 253 are illustrated, while the last outlet 253 can alternatively be axial in accordance with Figure 4.

[0112] The rest position and the first two operational positions can be as described above (Figures 3 to 5 for cumulative operation or Figure 6 for alternative operation of outputs 251, 252).

[0113] The left-hand configuration in Figure 7 illustrates a cumulative-reciprocating valve 200. The axial length 'd' of the piston 220 between the lateral outlet of the channel 223 and the front face 221 ensures alternating operation of the first two outlets 251, 252, while allowing cumulative operation of the first and third outlets 251, 253 when the cylindrical piston 220 assumes a third operating position where the lateral outlet of the channel 223 faces the third outlet 253, due to the inlet fluid pressure 240 reaching a third discharge pressure P3. In this example, the axial length 'd' is less than the distance dl separating the first and third outlets 251, 253, so that in the third operating position, the wall of the piston 220 does not block the first outlet 251.

[0114] The configuration on the right of Figure 7 illustrates, on the other hand, a fully alternating valve 200. The axial length 'd' ensures alternating operation of the three outlets 251, 252, 253, because it is greater than the distance dl so that in the third operating position, the wall of the piston 220 obstructs the first and second outlet paths 251.

[0115] Figures 8 and 9 illustrate embodiments in which the inlet channel 240 is arranged radially / laterally from the chamber 211 between two pistons 220, 220' actuated by respective return springs 230, 230'. These embodiments are called "T-shaped".

[0116] Chamber 211 consists of two cylindrical sub-chambers 211-1, 211-2 on either side of the inlet channel 240, each sub-chamber having at least one outlet channel and being able to operate in any of the configurations shown in Figures 3 to 7 previously. Each piston 220, 220' slides inside one of the respective sub-chambers, the return spring 230, 230' being dedicated to the corresponding sub-chamber (Le., to the corresponding outlet in the case of a single outlet per sub-chamber).

[0117] The position of the outlet ports 251, 252 (and, where applicable, the bypass port 260) in the sub-chambers and the spring settings 230, 230' are such that the first outlet port 251 is activated (by the inlet pressure PI) before the second outlet port 252 (by the inlet pressure P2). In the example shown in these figures, identical pistons and springs are used; it is the positions of the outlet ports that differ to correspond to different discharge pressures. Of course, identical relative positions can be provided, in which case different springs are used to define different discharge pressures. Different positions can also be combined with different springs.

[0118] In the example in Figure 8, pistons 220 and 220' are cylindrical. This is therefore a "T-shaped" piston valve. In the example in Figure 9, pistons 220 and 220' are ball-shaped or spherical. This is therefore a "T-shaped" ball valve. These valves combine the individual functions of the two arms of the T.

[0119] Figures 10 and 11 illustrate other embodiments of multi-outlet control valves 200 in which chamber 211 is formed of several cylindrical sub-chambers.

[0120] In the example in Figure 10, the cylindrical subchambers 211-a, 211-b are coaxial, of different diameters, and communicate with each other. Each subchamber includes at least one outlet channel and can operate as any of the configurations shown in Figures 3 to 7 previously.

[0121] Nevertheless, the pistons of the sub-chambers are made by a single piston 220. The latter is composed of several coaxial cylinders 220-a, 220-b configured to slide respectively in the several cylindrical sub-chambers 211-a, 211-b. As a result, only one return spring 230 is required.

[0122] The position of the outlet ports 251, 252 (and, if applicable, the bypass port 260) in the subchambers, the length of the smaller diameter cylinder 220-a, and the spring rate 230 are such that the first outlet port 251 is activated (by the inlet pressure PI) before the second outlet port 252 (by the inlet pressure P2). The stroke of the piston 220 and the spring rate 230 are calibrated with respect to the second outlet port 252 and the desired activation pressure P2. Based on this calibration, the length of the smaller diameter cylinder 220-a along the axis of the piston stroke is adjusted so that the activation of the first outlet port 251 corresponds to the desired activation pressure PI: the shorter the length, the earlier the outlet port 251 is opened.

[0123] Although the first outlet 251 is represented in the Figure as being that of the sub-chamber with the smaller cross-section and the second outlet 252 as being that of the sub-chamber with the larger cross-section, the reverse is possible.

[0124] Such a valve combines the individual functions of the two sub-chambers.

[0125] In the example of Figure 11, the (three or more) cylindrical subchambers are arranged in a star shape around the inlet channel 240. Each cylindrical subchamber 211-1, 211-2, 211-3 has its own sealed piston 220-1, 220-2, 220-3 sliding inside it under the combined action of the inlet pressure in the inlet channel and a respective return element 230-1, 230-2, 230-3.

[0126] Each subchamber includes at least one exit path and can operate as any of the configurations shown in Figures 3 to 7 previously.

[0127] The positions of the outlet ports 251, 252, 253 (and, where applicable, the bypass port 260) in the sub-chambers and the spring settings of 230-1, 230-2, 230-3 are such that the first outlet port 251 is activated (by the inlet pressure P1) before the second outlet port 252 (by the inlet pressure P2), and then before a third outlet port 253 (by the inlet pressure P3), and so on. In the example in the figure, identical pistons and springs are used; it is the positions of the outlet ports that differ to correspond to different discharge pressures. Of course, identical relative positions can be used, in which case different springs are used to define different discharge pressures. Different positions can also be combined with different springs.

[0128] Such a valve combines the individual functions of each of the branches (sub-chambers).

[0129] As can be seen from each of the embodiments described above, a method of operating a hydraulic or pneumatic circuit incorporating such a multi-outlet control valve 200 is as follows. A fluid is injected into the inlet port 210. Under the action of the inlet pressure and the return element 230, the sealed piston assembly 220 slides between different positions in the chamber. In these different positions, the piston assembly opens different flow paths between the inlet port 240 and different outlet ports 251, 252, 253, respectively.

[0130] Depending on the valve configuration, the output paths are cumulative or alternative. In a configuration with three or more output paths, these can even be cumulative-alternative.

[0131] Of course, the present invention is not limited to the embodiments described above by way of example; it extends to other variants.

Claims

DEMANDS 1. Fluidic control valve (200) for an aircraft turbomachine fluidic circuit, said valve (200) comprising a multi-way chamber (211), including an inlet (240), and a sealed piston assembly (220) sliding within the chamber under the combined action of an inlet pressure (P) in the inlet and a return element (230), valve in which the chamber comprises a plurality of outlets (251, 252, 253) and the piston assembly is configured to assume, with a first inlet pressure (P1), a first position opening a first flow path between the inlet (240) and a first outlet (251) and to assume, with a second inlet pressure (P2), a second position opening a second flow path between the inlet and a second outlet (252),the valve being characterized in that the two flow paths are mutually exclusive between the two positions taken by the piston assembly (220) in the chamber (211).

2. Control valve (200) according to claim 1, in which the piston assembly (220) consists of a single piston actuated by a return spring (230).

3. Control valve (200) according to claim 1, wherein the piston assembly (220) comprises two pistons (220, 220', 220-1, 220-2, 220-3) stressed by respective return springs (230, 230', 230-1, 230-2, 230-3).

4. Control valve (200) according to any one of claims 1 to 3, wherein the chamber (21 1 ) is formed of a single cylindrical chamber.

5. Control valve (200) according to any one of claims 1 to 3, wherein the chamber (211) is formed of several coaxial cylindrical sub-chambers (211-a, 211-b), of different diameters, communicating with each other and each having at least one outlet (251, 252), and the piston assembly (220) comprises a piston composed of several coaxial cylinders (220-a, 220-b) configured to slide respectively in the several cylindrical sub-chambers.

6. Control valve (200) according to any one of claims 1 to 3, in which the chamber (211) is formed of several cylindrical sub-chambers (211-1, 211-2, 211-3) arranged in a star around the inlet channel (240), each cylindrical sub-chamber having its own sealed piston (220-1, 220-2, 220-3) sliding inside it under the combined action of the inlet pressure (P) in the inlet channel and a respective return element (230-1, 230-2, 230-3).

7. Control valve (200) according to any one of claims 1 to 6, wherein the outlet paths (251, 252, 253) are arranged radially from a cylindrical part of the chamber (211), two radial outlet paths (251, 252) being arranged at the same height of the cylindrical part of the chamber (211).

8. Control valve (200) according to any one of claims 1 to 6, in which an outlet (252) is disposed axially at one end (213) of a cylindrical portion of the chamber (211), the chamber (211) comprising a bypass zone (260) external to the cylindrical portion in which a piston (220) slides, the bypass zone extending between two bypass orifice zones (01, 02) of the cylindrical portion separated by a distance (D) greater than the axial length (d) of the piston (220).

9. Control valve (200) according to any one of claims 1 to 8, wherein the piston assembly (220) comprises a piston having a channel (223) extending from a face of the piston (221) opposite the inlet channel (240) and a lateral face of the piston, the piston (220) having an axial length (d) such that when the channel (223) is opposite a second outlet channel (252), a lateral wall (225) of the piston obstructs a first outlet channel (251).

10. Aircraft turbomachine, comprising a fluidic circuit including at least one control valve according to any one of claims 1 to 9.

11. Aircraft turbomachine according to claim 10, comprising a lubrication group forming a fluidic circuit including at least one regulating valve.

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