Apparatus for controlling a flow guiding system, in particular in a turbine engine of an aircraft

Abstract

An apparatus (30) for controlling an airflow directing system (20), the apparatus comprising at least one actuator (31) configured to translate a control lever (32) between a first end position and a second end position of a nominal working range, wherein at least one blade (21a) of the airflow directing system (20) is movable between a first angle and a second angle, the control lever (32) being connected with the blade (21a) by a control lever (33) comprising a first control link (36) and a second control link (37) hinged together. The actuator (31) is configured to bring the control lever (32) into a safety position located outside the second end position of the nominal working range and to orient the blade (21a) at a safety pitch angle between the first angle and the second angle.

Description

Technical Field

[0001] This invention relates to the field of aircraft, and in particular to aircraft turbine engines.

[0002] More specifically, the present invention relates to the control of an airflow guiding system. Background Technology

[0003] Generally speaking, a turbine engine includes a compressor, a combustion chamber located at the outlet of the compressor, a high-pressure turbine designed to drive the compressor to rotate, and a low-pressure turbine designed to drive the propeller blades of an aircraft to rotate.

[0004] The turbine engine also includes an airflow guidance system, known as an "inlet guide vane" (IGV), which consists of multiple finned or variable-pitch inlet guide vanes positioned upstream of the compressor and allows for increased compressor efficiency, thereby improving the engine's thermodynamic cycle at cruise speeds. This system helps reduce the aircraft's fuel consumption.

[0005] "Variable pitch" should be understood as synchronizing the angular position of all blades in the same stage by means of a control ring or control crown fixed to all blades. Each blade is connected to the control ring via a control link.

[0006] It is known to control the position of the blades using a cylinder system fixed to a housing and including a piston movable within a cylinder chamber between two ends of the engine's nominal operating range. This piston is connected to a control crown via a control rod. During the piston's movement between the first and second ends, the blades can move continuously between a first and a second angle.

[0007] Generally, piston movement is controlled by a fluid distributor, such as an oil separator in the case of hydraulic control.

[0008] If the components controlling the blade kinematics malfunction, the position of the piston and therefore the blade pitch angle will no longer be known.

[0009] It is necessary to know the position of the piston at all times and therefore the blade pitch angle, and to do so reliably. Summary of the Invention

[0010] Therefore, the present invention aims to overcome the shortcomings of the control devices of the above-mentioned airflow guidance system.

[0011] The purpose of this invention is to improve safety in the event of a failure in the components controlling the blade kinematics.

[0012] Therefore, the object of the present invention is a device for controlling an airflow guiding system, the airflow guiding system including at least one blade movably rotatable between a first angle and a second angle about a rotation axis, the control device including at least one actuator configured to drive a control lever to translate between a first end position and a second end position within a nominal operating range, wherein the blade is movable between the first angle and the second angle, the control lever being connected to the axis of the blade via a control lever hinged relative to a free end of the control lever opposite to an end connected to the actuator.

[0013] The control lever includes a first control link and a second control link. The first link includes a first end hinged to the free end of the control lever and a second end hinged to the first end of the second link. The second link also includes a second end opposite to the first end of the second link, and the second end of the second link is fixed to the blade and rotates.

[0014] In the event of a control device malfunction, the actuator is configured to bring the control lever to a safe position outside the second end position of the nominal operating range and orient the blades at a safe pitch angle between the first and second angles.

[0015] The safe position and safe blade pitch angle correspond to the so-called safe position, which allows airflow even in the event of a control equipment failure. Therefore, in the event of a control equipment failure, the piston position and blade pitch angle are known at all times and are reliably achieved.

[0016] Advantageously, the actuator is configured to transmit pure axial motion to the control lever according to the actuator's axis of motion.

[0017] According to one embodiment, the control lever includes only a first control link and a second control link, and the first control link and the second control link are hinged together by a ball-joint connection.

[0018] The airflow guidance system can be a blade type with inlet guide vanes or so-called "inlet guide vanes" with variable pitch, abbreviated as "IGV". Inlet guide vanes include multiple stator fins or stator blades, which include main blades connected to a control lever and multiple auxiliary blades whose movement is synchronized with the movement of the main blades. The control device also includes a control ring or control crown connected to a control lever and connected to the auxiliary blades via a secondary linkage. The rotation axis of these blades is perpendicular to the axis of the control ring.

[0019] Therefore, each secondary blade is connected to the control loop via a control link.

[0020] "Variable pitch" blades should be understood as all secondary blades being in the same position relative to the primary blade.

[0021] "Stator" blades should be understood as blades carried by the stator and capable of rotating movably around their own axis of rotation.

[0022] According to one embodiment, the length of the second control link is approximately equal to the length of the auxiliary link, and the control ring is hinged to the second control link at a point coinciding with the ball-and-socket joint connection between the two control links.

[0023] According to another embodiment, the length of the second control link is greater than the length of the secondary link, and the control ring is hinged to the second control link at a point away from the ball joint connection between the two control links.

[0024] For example, the control device may include two actuators, which are, for example, radially opposite or diametrically opposed.

[0025] The actuator may include an actuator rod that is connected to the control rod via a rigid connection or a ball joint connection.

[0026] Without limitation, the actuator may be a cylinder including a body defining a cylindrical chamber in which a piston is translatably mounted, the piston including an end connected to a control lever, the piston being configured to perform over-stroke when the control lever is moved to a safe position.

[0027] The cylinder body may include two orifices leading to a chamber, serving as an inlet and outlet for fluid, designed to allow a piston to slide within the cylinder body along an axial axis. For example, fluid (e.g., oil) is supplied to the cylinder chamber via a first orifice from an external energy source. Under pressure applied by the fluid to the piston's back surface, the piston moves axially along its axis together with a control rod. The external energy source may be a hydraulic control system including a distributor or servo valve configured to distribute fluid within the cylinder chamber. The piston's stroke can be determined based on the servo valve.

[0028] According to another aspect, the present invention relates to an aircraft turbine engine comprising, from upstream to downstream, in the direction of airflow flow: an inlet sleeve for receiving air, a centrifugal compressor, an annular combustion chamber located downstream of the compressor, a high-pressure power turbine intended for driving the compressor to rotate, an output turbine intended for driving the output shaft to rotate via a low-pressure shaft, an airflow guiding system located upstream of the compressor, and control equipment for the airflow guiding system as defined above.

[0029] Advantageously, the rotation axis of the blades in the airflow system is perpendicular to the central axis of the turbine engine.

[0030] The nominal operating range corresponds to the nominal operating range of the turbine engine.

[0031] The actuator rod can move along the axial axis of the turbine engine.

[0032] According to another aspect, the present invention relates to a single-engine helicopter including a turbine engine as described above. Attached Figure Description

[0033] Other objects, features, and advantages of the invention will become apparent from the following description, which is given by way of non-limiting example only and with reference to the accompanying drawings, in which:

[0034] Figure 1 A cross-sectional view of an aircraft turbine engine, including devices for controlling an airflow guidance system according to the present invention, is shown in a very schematic manner.

[0035] Figure 2 It indicates Figure 1 Airflow guidance system;

[0036] Figure 3 yes Figure 1 Detailed 3D view of the control equipment;

[0037] Figure 4 , Figure 5 and Figure 6 It schematically represents Figure 1 The three positions of the control equipment of the airflow guidance system and the three positions of the main blades; and

[0038] Figure 7 This illustrates an airflow guiding system according to another embodiment. Detailed Implementation

[0039] In the following description, the terms "upstream" and "downstream" are defined relative to the direction of air circulation in the turbine engine.

[0040] exist Figure 1 The diagram illustrates, in a very schematic manner, the axial section of the turbine engine 10, whose central axis A corresponds to the axis of the turbine engine's power shaft (or low-pressure shaft). As a non-limiting example, a single-engine helicopter could be equipped with this turbine engine.

[0041] The turbine engine 10 includes, from upstream to downstream, an inlet sleeve 11 for receiving air, and a centrifugal compressor 12, for example, having one or two stages, configured to draw in airflow F. The turbine engine 10 also includes: an annular combustion chamber 13, such as a counter-flow combustion chamber, located downstream of the compressor 12; a high-pressure power turbine 14 intended for driving the compressor 12 to rotate via a high-pressure shaft 15; an output turbine 16, such as a single-stage turbine, intended for driving the output shaft 17 to rotate via a low-pressure shaft 18 coaxial with the high-pressure shaft 15; and a reduction gear system 19.

[0042] Output shaft 17 is connected to the aircraft's propeller blades.

[0043] The turbine engine 10 also includes an airflow guidance system 20, referred to as an "inlet guide vane" or "IGV", which includes multiple variable pitch fins or guide vanes 21 and is located upstream of the compressor 12.

[0044] Multiple variable pitch blades 21 include a main blade 21a and multiple auxiliary blades 21b, the movement of which is synchronized with the movement of the main blade 21a.

[0045] The blade 21, which consists of blades 21a and 21b, is a so-called "stator" blade, meaning that each blade 21a and 21b can rotate around its own axis of rotation.

[0046] In this paper, the rotation axes of blades 21a and 21b are perpendicular to the central axis A of the turbine engine 10.

[0047] The turbine engine 10 also includes a device 30 for controlling the airflow guidance system 20.

[0048] The control device 30 of the airflow guiding system 20 includes an actuator 31 and a control lever 32. The control lever 32 is driven to translate by the actuator 31 and connected to the axis of the main blade 21a via a control lever 33. The control device 30 also includes a control ring or control crown 34 connected to the control lever 33. The control ring or control crown 34 is hinged relative to the control lever 33 and to a secondary link 35, which is fixed together with the secondary blade 21b and rotates. In other words, each secondary blade 21b is connected to the control ring 34 via the secondary link 35.

[0049] The “variable pitch” blade should be understood as all the secondary blades 21b being in the same position relative to the main blade 21a.

[0050] The rotation axes of blades 21a and 21b are perpendicular to the axis of control ring 34.

[0051] Without limitation, actuator 31 may be a cylinder comprising a body fastened to a housing (not labeled) and defining a cylindrical chamber in which a piston is translatably mounted, one end of which is connected to control lever 32.

[0052] The control lever 32 is connected to the axis of the blade 21a via a control lever 33. The control lever 33 is hinged relative to the free end 32a of the control lever 32, which is opposite to the end connected to the actuator 31.

[0053] The cylinder body may include two orifices leading to the chamber, which serve as an inlet and outlet for fluid, and are designed to allow the piston to slide within the cylinder body along a motion axis X-X' that is substantially parallel to the central axis A of the turbine engine 10.

[0054] For example, fluid (e.g., oil) is supplied to the cylinder chamber via a first orifice using an external energy source. Under the pressure exerted by the fluid on the piston's back surface, the piston moves axially along the X-X' axis together with the control rod 32.

[0055] The external energy source can be a hydraulic control system, which includes a distributor or servo valve configured to distribute fluid within the cylinder chamber. The piston stroke can be determined based on the servo valve.

[0056] The piston of the cylinder can translate within the cylinder chamber between two end positions within the nominal operating range of the turbine engine. During the movement of the piston between the first end position and the second end position, the main blade 21a can move continuously between a first angle α1 and a second angle α2, the first angle and the second angle being respectively defined between the main blade 21a and a horizontal axis parallel to the axis of motion X-X'. Figure 2 The fixed angle α shown is limited between the main blade 21a and the second control link 37, which is fixed together with the main blade and rotates.

[0057] The control device 30 is configured to guide the piston, thereby guiding the control lever 32 toward a safe position where the piston stroke is known, and thus the opening angle of the blades 21a, 21b is known.

[0058] The safe position PS corresponds to the open position of the blade, in which the turbine engine can operate safely. The main blade 21a moves from the second angle α2 to the safe angle αS.

[0059] The safe position PS is one of the positions P1 and P2 that is far from the nominal working range.

[0060] The piston is configured to perform overtravel beyond one of its multiple end positions.

[0061] like Figure 3 As shown, the control lever 33 comprises two distinct parts: a first control link 36 and a second control link 37.

[0062] The first control link 36 includes a first end 36a hinged to the free end of the control lever 32 (which is opposite to the end connected to the piston), and a second end 36b hinged to the first end 37a of the second control link 37. In other words, the two control links 36 and 37 are connected by a ball joint connector.

[0063] The second control link 37 also includes a second end 37b opposite to the first end 37a hinged to the first link 36, the second end of which is fixed to the main blade 21a for rotation. In other words, the second control link 37 is fastened to the main blade 21a so as to rotate together with the main blade, i.e., the entire second link rotates together with the main blade 21a. The axis of rotation of the main blade 21a is marked 20a.

[0064] The free end of the piston is connected to the control rod 32 via a rigid connection or a ball joint connection.

[0065] like Figure 3 As shown, the length of the second control link 37 is substantially equal to the length of the secondary link 35. The control ring 34 is hinged to the second control link 37 at the point where it coincides with the ball-and-socket joint connection between the two control links 36 and 37.

[0066] The control lever 32 is configured to translate only along the motion axis X-X' during the piston movement of the cylinder. The control lever 32 has a single degree of freedom, namely, the degree of freedom along the motion axis X-X'.

[0067] The movement of control lever 32 is as follows Figures 4 to 6 As shown.

[0068] Figure 4This indicates the first end position P1 of the free end 32a of the control lever 32 when the actuator rod or piston is in the first end position of the nominal operating range of the turbine engine 10. At the first end position P1 of the control lever 32, the main blade 21a opens at a first angle α1, which is, for example, between 45° and 75°, and for example, greater than or equal to 60°.

[0069] Figure 5 This indicates the second end position P2 of the free end of the control lever 32 when the actuator rod or piston is in the second end position of the nominal operating range of the turbine engine 10. During the movement of the control lever 32 from the first end position P1 towards the second end position P2, the main blade 21a gradually moves from a first angle α1 towards a second angle α2, for example, equal to 0°. The flow velocity is maximum at this second end position.

[0070] Figure 6 This indicates the safe position PS of the free end of the control lever 32 when the actuator rod or piston performs overtravel or extends beyond the nominal operating range of the turbine engine 10 to a second end position. During the movement of the control lever 32 from the second end position P2 toward the safe position PS, the main blade 21a gradually moves from a second angle α2 toward a safe pitch angle αS, which is between angles α1 and α2, for example, between 5° and 15°, or equal to 8°. In the illustrated example, a fixed angle α is set equal to the safe pitch angle αS such that when the safe position PS is reached, the second control link 37 is oriented parallel to the axis of motion X-X'. However, without departing from the scope of the invention, angles α and αS can be set differently from each other. For example, to move the safe position PS, the additional overtravel of the actuator rod, and therefore the additional overtravel of the control lever 32, increases the value of the safe pitch angle αS, while angle α remains unchanged.

[0071] exist Figure 7 In the illustrated embodiment (where the same elements have the same reference numerals), the length of the second control link 37 is greater than the length of the secondary link 35. The control ring 34 is hinged to the second control link 37 at a point away from the ball-and-socket joint between the two control links 36 and 37.

[0072] A linear relationship was obtained between the position of control lever 32 and the pitch angle of main blade 21a.

[0073] Generally, the use of control device 30 is not limited to turbine engines, and can be used to ensure the movement of control levers in the event of a component failure, thereby ensuring that the fins mounted upstream of the steering wheel are oriented to a safe position. The safe pitch angle of the blades is within the pitch angle range required for the nominal operation of the steering wheel. This safe pitch angle is reached when the actuator lever of the control device overtravels.

[0074] In view of the present invention, the control lever can be brought to a reliable safe position, and thus the blade pitch angle can be brought to a reliable safe position.

Claims

1. A control device (30) for controlling an airflow guiding system (20), the airflow guiding system comprising at least one blade (21a) movably rotatable about a rotation axis between a first angle (α1) and a second angle (α2), the control device (30) comprising at least one actuator (31) configured to drive a control lever (32) to translate between a first end position (P1) and a second end position (P2) within a nominal operating range, wherein, The blade (21a) is movable between the first angle (α1) and the second angle (α2), the control rod (32) is connected to the axis of the blade (21a) via a control lever (33), the control lever is hinged relative to the free end of the control rod (32), and the free end of the control rod is opposite to the end connected to the actuator (31), characterized in that, The control lever (33) includes a first control link (36) and a second control link (37). The first control link (36) includes a first end (36a) hinged to the free end of the control rod (32) and a second end (36b) hinged to the first end (37a) of the second control link (37). The second control link (37) also includes a second end (37b) which is opposite to the first end (37a) of the second control link and rotates together with the blade (21a). The actuator (31) is configured to bring the control rod (32) to a safe position (PS) outside the second end position (P2) of the nominal operating range and to orient the blade (21a) at a safe pitch angle (αS) between the first angle (α1) and the second angle (α2). The control lever (33) comprises only the first control link (36) and the second control link (37), and the first control link and the second control link are hinged together by a ball joint connector. The airflow guiding system (20) includes multiple variable-pitch stator blades (21), each of which includes a main blade (21a) and multiple auxiliary blades (21b). The main blades are connected to the control lever (33), and the movement of the auxiliary blades is synchronized with the movement of the main blade (21a). The control device (30) also includes a control ring (34), which is connected to the control lever (33) and to the auxiliary blades (21b) via a secondary connecting rod (35). The rotation axes of the main blades (21a) and the auxiliary blades (21b) are perpendicular to the axis of the control ring (34). The length of the second control link (37) is approximately equal to the length of the secondary link (35), and the control ring (34) is hinged to the second control link (37) at the point where it coincides with the ball joint connection between the first control link (36) and the second control link (37).

2. The control device (30) according to claim 1, wherein, The actuator (31) is configured to transmit pure axial motion to the control lever (32) according to the motion axis (X-X') of the actuator (31).

3. The control device (30) according to claim 1 or 2, wherein, The actuator (31) includes an actuator rod that is connected to the control rod (32) via a rigid connection.

4. The control device (30) according to claim 1 or 2, wherein, The actuator (31) is a cylinder, which includes a body defining a cylindrical chamber in which a piston is translatably mounted, one end of which is connected to the control lever (32), and the piston is configured to perform overtravel when the control lever (32) is moved to the safe position (PS).

5. A turbine engine (10) for an aircraft, the turbine engine comprising, from upstream to downstream, components in the direction of airflow: The air inlet sleeve (11), centrifugal compressor (12), an annular combustion chamber (13) located downstream of the compressor (12), a high-pressure power turbine (14) intended to drive the compressor (12) to rotate, an output turbine (16) intended to drive the output shaft (17) to rotate, an airflow guiding system (20) located upstream of the compressor (12), and a control device (30) for controlling the airflow guiding system (20) according to any one of claims 1 to 4.

6. The turbine engine (10) according to claim 5, wherein, The rotation axis of the blades (21a) of the airflow guiding system (20) is perpendicular to the central axis (A) of the turbine engine (10).

7. A single-engine helicopter, the single-engine helicopter comprising a turbine engine (10) according to claim 5 or 6.

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