Pressure gauge with attached leading edge

Description

Domaine technique

[0001] The present invention relates to a pressure measuring rake, in particular for an aircraft engine, and more particularly for a turbofan engine. Etat de la technique

[0002] During certain phases of aircraft design or maintenance, the aircraft's engines, particularly turbofan engines, may be tested. These tests require measurements to be taken, on the ground and / or in flight, at various locations within the engine being tested. These measurements necessitate engine instrumentation, especially within a secondary flow. For this purpose, measurement tools are available that can be installed in an engine under test, notably for measuring pressures.

[0003] However, these measurement tools are often difficult and time-consuming to assemble and set up, which can make the testing phases laborious and expensive.

[0004] A measuring tool for taking pressure measurements in an aircraft engine is known from document FR 3 090 102 A1. However, the disclosed measuring tool has a less than optimal design. It is designed to be assembled by gluing, which prevents disassembly, for example, to replace or reposition components. Furthermore, the injection of glue or resin is difficult to control, particularly in terms of dosage. Too much can clog cavities, while too little can cause leaks, which can then interfere with measurements. Patent documents FR 3 079 613 A1, FR 3 065 806 A1, and US 2019 / 323909 A1 disclose other examples of pressure measuring rakes for aircraft engines.

[0005] Existing measurement tools are therefore not completely satisfactory. Exposé de l'invention

[0006] The present invention aims to overcome the aforementioned drawbacks. It relates to a pressure measuring rake, particularly for an aircraft engine, and more specifically for a turbofan engine.

[0007] According to the invention, the measuring rake, intended to be mounted on a connecting rod, comprises at least: a sleeve comprising a front face and two side walls delimiting, between them, a housing intended to receive the connecting rod; an electronic circuit arranged on the front face of the sleeve and comprising at least one sensor; and an added leading edge removably fixed to the sleeve, said added leading edge comprising an inner face arranged on the front face of the sleeve so as to cover the electronic circuit, an outer face opposite said inner face, and a plurality of air intakes distributed along a length of the added leading edge, each of said air intakes forming a fluidic passage between the outer face and the inner face of the added leading edge opening onto the electronic circuit through said inner face, opposite at least one sensor of the electronic circuit.

[0008] Thus, thanks to the measuring rake, we have a measuring tool that is particularly simple and quick to assemble, the removable leading edge allowing, in particular, easy access to the electronic circuit, for example to change or repair a defective sensor, and also avoiding assembly by gluing and therefore the problems that are related to it, for example blockages of orifices or air leaks.

[0009] Preferably, the measuring rake also includes at least one joint arranged, in a removable manner, between the inner face of the attached leading edge and the front face of the sheath; said joint being pressed against the electronic circuit, covering it, at least partially.

[0010] Advantageously, the joint includes at least one through opening opposite at least one sensor of the electronic circuit; each of said openings forming, between the electronic circuit and the inner face of the attached leading edge, a cavity hermetically isolated from another cavity; each cavity comprising at least one sensor; each air intake of the attached leading edge communicating exclusively with one cavity.

[0011] Furthermore, in a preferred embodiment, the attached leading edge includes at least one measuring tip arranged on the outer face of said attached leading edge in line with each air intake; each measuring tip having a cylindrical shape capable of channeling an airflow incident to said outer face into its respective air intake.

[0012] Advantageously, the attached leading edge has, on the outer face, at least one tapped hole through which opens at least one air intake; each measuring tip corresponding to an attached part screwed into a tapped hole.

[0013] In addition, the measuring rake includes at least one fixing element to attach the leading edge attached to the sheath.

[0014] In a particular embodiment, the measuring rake further comprises at least one counter plate arranged on a rear face of the sheath opposite the front face; said counter plate being provided, along its length, with a plurality of passage holes allowing the passage of the fastening elements from inside the sheath; said fastening elements passing through at least the counter plate, the sheath, the seal and the electronic circuit to reach the attached leading edge so as to fix said attached leading edge to the sheath.

[0015] In addition, the measuring rake includes at least one data processing unit capable of receiving data measured by the sensors of the electronic circuit, said data processing unit being integrated into the sheath or remote.

[0016] The invention also relates to an aircraft engine. According to the invention, the engine comprises a secondary flow and at least one movable reversing gate; said reversing gate comprising at least one fixed connecting rod articulated between the reversing gate and a motor; said connecting rod being configured to allow the reversing gate to be brought into a retracted position in which it is not across the secondary flow and into a deployed position in which it is across the secondary flow, said engine comprising at least one measuring rake as described above arranged on at least one connecting rod of the engine; said connecting rod(s) each being housed in the housing of at least one measuring rake.

[0017] The invention also relates to an aircraft comprising at least one engine as described above. Brève description des figures

[0018] The accompanying figures will clearly illustrate how the invention can be implemented. In these figures, identical reference numerals designate similar features. figure 1 is a side view of an aircraft according to the invention. figure 2 is a side view, in cross-section, of a motor according to the invention comprising reversing gates in a retracted position. figure 3 is a side view, in cross-section, of a motor according to the invention comprising reversing gates in a deployed position. figure 4 is a side view of a measuring rake according to a particular embodiment of the invention. figure 5 is an exploded view of the measuring rake of the figure 4 . There figure 6 is a cross-sectional view along a cutting plane AA of the measuring rake of the figure 4 . Description détaillée

[0019] The pressure measuring rake 1 (hereinafter referred to as measuring rake 1), used to illustrate the invention, is shown in particular embodiments of the figure 2 to the figure 6 It corresponds to a measuring tool used to perform aerodynamic measurements, particularly pressure measurements. Although not exclusively, the measuring rake 1 is particularly well-suited for use on an AC aircraft, as shown in the diagram. figure 1 It allows measurements to be taken during ground and / or flight tests. Preferably, the measuring rake 1 is arranged in a channel of an engine 2 of the aircraft AC, as shown in the figure 2 and the figure 3 .

[0020] The AC aircraft comprises a fuselage 3 on each side of which is fixed a wing 4 carrying an engine 2 fixed to a mast 5 located under said wing 4. In the preferred embodiment described herein, the engine 2 corresponds to a turbofan engine and the measuring rake 1 is configured to perform pressure measurements in a secondary duct 6 of said engine 2. However, the invention is not limited to such an engine and the measuring rake 1 can be used in a large number of different and varied situations in which the pressure of an airflow must be measured.

[0021] In what follows, we will refer to an orthogonal coordinate system (X, Y, Z) such that: X is the longitudinal axis of engine 2 which is parallel to the longitudinal axis of aircraft AC and oriented positively towards the front of said aircraft AC; Y is the transverse axis to the engine and perpendicular to the X axis; and Z is the axis perpendicular to the X axis and to the Y axis.

[0022] As depicted on the figure 2 and the figure 3 The engine 2 comprises a fan 7, a motor 8 forming a core, and a nacelle 9 arranged around the motor 8. The secondary duct 6 is delimited between the motor 8 and the nacelle 9. Air enters through the fan 7 and is then divided into a primary flow that passes through the motor 8 and a secondary flow that passes through the secondary duct 6, as represented by arrows F on the diagram. figure 2 and the figure 3 .

[0023] The motor 2 also includes a thrust reversing system which comprises reversing gates 10. These reversing gates 10 are mounted to rotate about an axis substantially perpendicular to the X-axis, or parallel to the Y-axis. They can be brought into a retracted position ( figure 2 ), corresponding to a configuration where motor 2 is in push mode, and in a deployed position ( figure 3 ), corresponding to a configuration where the motor 2 is in reverse thrust mode. In the retracted position, the reversing doors 10 are contained within the walls of the nacelle 9; they are not across the secondary duct 6, and therefore do not obstruct the passage of the secondary airflow. In the deployed position, the reversing doors 10 extend from the motor 8 to the walls of the nacelle 9; they are across the secondary duct 6, and therefore obstruct the passage of the secondary airflow. Furthermore, in this deployed position, the reversing doors 10 open windows 11 that communicate with the outside of the nacelle 9 and allow the secondary airflow to be diverted through said windows 11.

[0024] In addition, the engine 2 has a connecting rod 12 arranged on each reversing gate 10. Each connecting rod 12 comprises a body 14 ( figure 6 ) provided with an elongated shape extending between the motor 8 and the reversing gate 10 on which it is arranged. In addition, one longitudinal end 15 of each connecting rod 12 is hinged to the reversing gate 10 and another longitudinal end 16 of each connecting rod 12 is hinged to the motor 8. Furthermore, the body 14 of each connecting rod 12 has an aerodynamic cross-section around which the secondary airflow from the secondary channel 6 flows.

[0025] The motor 2 also includes standard movement elements (cylinders, slides, etc.) allowing the reversing doors 10 to be brought into the retracted position and into the deployed position via connecting rods 12.

[0026] In the deployed position, the connecting rods 12 are transverse to the secondary airflow 6; that is, they are oriented so that their longitudinal direction is substantially incident to the secondary airflow. Conversely, in the retracted position, the connecting rods 12 are not transverse to the secondary airflow 6; that is, they are oriented so that their longitudinal direction is substantially in the direction of the secondary airflow.

[0027] In the preferred embodiment, represented by the figure 2 to the figure 6 The measuring rake 1 is configured to allow for secondary airflow pressure measurements in the secondary duct 6, particularly when the reversing gate 10 is in the retracted position. In this embodiment, the measuring rake 1 is arranged on a connecting rod 12 of the engine 2; however, in other embodiments, it can be configured to be arranged on another element of the engine 2 or the AC aircraft.

[0028] The measuring rake 1, shown in the image figure 4 to the figure 6 , is a measuring tool comprising various removable elements that can be mounted and dismounted. Indeed, a "removable" element is defined as one that is attached to an assembly in such a way that it can be separated from the assembly and subsequently remounted at will without damaging the assembly. As illustrated in the exploded view of the figure 5 The measuring rake 1 is configured so that its various component parts are assembled and fixed together "in a sandwich" configuration. This assembly is described in more detail later in the description.

[0029] The measuring rake 1 includes, in particular, a sleeve 17 which is positioned and fixed on the body 14 of the connecting rod 12 to be instrumented. This sleeve 17 has an elongated shape and an aerodynamic profile, for example, a biconvex profile. Preferably, the sleeve 17 is made by three-dimensional printing in a polymer-type material, for example, polyamide.

[0030] The measuring rake 1 has a length suitable for covering, at least in part, the entire connecting rod 12. By way of non-limitation, in the example considered of an application to an aircraft engine, the measuring rake 1 typically has a length between 50 cm and 1 m, in particular a length of 80 cm.

[0031] As shown in cross-sectional view on the figure 6 The sleeve 17 comprises two side walls 18A and 18B, which define a housing 19 configured to receive the body 14 of the connecting rod 12. Furthermore, the housing 19 communicates with the exterior of the sleeve 17 via a slot 20 extending along the length of the sleeve 17 between the side walls 18A and 18B. These form a clamp for gripping the body 14 of the connecting rod 12. In addition, the sleeve 17 is open at longitudinal ends 21 and 22, allowing the longitudinal ends 15 and 16 of the connecting rod 12 to protrude from the sleeve 17 in order to be attached, respectively, to the drive unit 8 and the reversing gate 10.

[0032] Slot 20 is narrower than the thickness of the connecting rod body 14, and therefore the insertion of said connecting rod 12 requires elastic separation of the side walls 18A and 18B for the positioning of the measuring rake 1 onto the connecting rod 12. Elastic tightening of the side walls 18A and 18B on the connecting rod body 14, when the latter is in the housing 19, allows the measuring rake 1 to be held in place without the need for additional elements. The body 14 may, however, have shapes or elements (not shown) to facilitate the positioning of the measuring rake 1 and / or to prevent the sleeve 17 from moving along the connecting rod 12.

[0033] In one particular embodiment, the side walls 18A and 18B can be held tightly together on the body 14 of the connecting rod 12 by means of a removable fastener (not shown). For example, they can be screwed, bolted, glued, or clamped with a hose clamp.

[0034] The sleeve 17, when in place on the connecting rod 12 in the secondary channel 6, has a leading edge 23 oriented towards the front (positively along the X axis) and a trailing edge 24 oriented towards the rear (negatively along the X axis) with respect to the airflow in the secondary channel 6. Preferably, the sleeve 17 is configured so that the slot 20 is located at the trailing edge 24.

[0035] Furthermore, as illustrated on the figure 5 and the figure 6 The measuring rake 1 includes an electronic circuit 25 removably arranged on the sleeve 17. This electronic circuit 25 is, in particular, provided with a face 26 arranged on a front face 27 of the sleeve 17. The front face 27 corresponds to a surface located on the side of the leading edge 23 which extends over the length of said sleeve 17. The electronic circuit 25 is also provided with a face 28, opposite to the face 26 and therefore oriented towards the leading edge 23, on which a plurality of pressure sensors 29 are arranged.

[0036] Preferably, the electronic circuit 25 is a printed circuit board with an elongated shape and is arranged along the entire length of the front face 27. However, in particular embodiments, it may be another type of electronic circuit extending over all or part of the front face 27. In addition, the sensors 29 are distributed so as to form a line extending along the length of the electronic circuit 25.

[0037] The electronic circuit 25 also includes a data bus for incoming and / or outgoing data communication with the sensors 29, as well as a power supply. In the preferred embodiment of this description, the sensors 29 are configured to measure pressure values ​​generated by the secondary airflow of the secondary vein 6, as detailed later in the description.

[0038] Preferably, the sensors 29 are microelectromechanical systems (MEMS) pressure sensors. However, other types of sensors suitable for pressure measurements may also be used. For example, and not limited to, particularly compact MEMS sensors allow for a line of sensors 29 along the electronic circuit 25 with a density of fifty sensors per meter, which is one sensor every 20 mm. Depending on the application and / or the required measurement accuracy, the sensor density can vary, for example, with a distance between two sensors 29 ranging from 10 mm to 100 mm.

[0039] In addition, the measuring rake 1 includes a data processing unit 30, schematically represented on the figure 5 The data processing unit 30 is connected to the electronic circuit 25 so as to receive data measured by the sensors 29 of said electronic circuit 25. By way of exception, the data processing unit 30 can be configured to perform an acquisition and transmission function for the data measured by the sensors 29 and / or a recording function, for example, in a memory (not shown). In one particular embodiment, the data processing unit 30 is integrated directly onto the measuring rake 1, for example, in a part of the sleeve 17. In other embodiments, the data processing unit 30 can be located elsewhere. For example, it can be arranged on a part of the motor 2, on or under the reversing gate 10.

[0040] In one of these embodiments, the measuring rake 1 may include a foot (not shown in the figures) arranged at one end of the sleeve 17. The foot has a flat shape. The foot is configured to protect the data processing unit 30 when it is arranged on the measuring rake 1. The foot is adapted to be pressed against the reversing door 10 so as to cover the data processing unit 30 and protect it from the external environment.

[0041] As represented by the figure 4 to the figure 6 The measuring rake 1 also includes an attached leading edge 31 fixed to the front face 27 of the sheath 17. It is a removable one-piece part which covers the entire front face 27. It can be made by machining from a metallic material, preferably aluminum.

[0042] The leading edge 31 comprises an inner face 32 arranged on the front face 27 of the sleeve 17 so as to cover the electronic circuit 25. It also comprises an outer face 33 opposite said inner face 32. As illustrated in the figure 5 , the external face 33 is located towards the leading edge 23 of the sleeve 17 and it has a rounded shape intended to be incident to the secondary airflow.

[0043] The leading edge 31 further comprises a plurality of air inlets 34 distributed along the length of said attached leading edge 31. In the example illustrated on the figure 4 and the figure 5 The air inlets 34 are distributed at regular intervals, i.e., at the same distance from each other. However, they can also be distributed at irregular intervals. Each air inlet 34 forms a fluid passage between the outer face 33 and the inner face 32. These air inlets 34 have an end 35 opening through the outer face 33 into the secondary flow 6 and an end 36 opening through the inner face 32 onto the electronic circuit 25. In particular, each air inlet 34 opens through its end 36 opposite a sensor 29 of the electronic circuit 25.

[0044] The leading edge 31, thus configured, allows each sensor 29 to measure the pressure of the airflow from the secondary stream 6 channeled through a specific air inlet 34. However, in certain embodiments, each air inlet 34 can open opposite a plurality of sensors 29 so as to perform several measurements related to an airflow channeled through an air inlet 34.

[0045] Thus, thanks to the measuring rake 1, a pressure measuring tool is available that is particularly simple and quick to assemble. The removable leading edge 31 allows easy access to the electronic circuit 25, for example, to change or repair a faulty sensor 29. Furthermore, the measuring rake 1 has a design that eliminates the need for gluing and therefore the associated problems, such as blocked orifices or air leaks.

[0046] Furthermore, as represented by the figure 4 to the figure 6 The measuring rake 1 includes a seal 37 removably arranged between the attached leading edge 31 and the sleeve 17. More specifically, the seal 37 comprises a face 38 arranged against the inner face 32 of the attached leading edge 31 and a face 39 arranged against the face 28 of the electronic circuit 25. The attached leading edge 31 is fixed to the sleeve 17 so as to press the seal 37 against the face 28 of the electronic circuit 25. Furthermore, the seal 37 has an elongated rectangular shape similar to that of the electronic circuit 25 on which it rests. Preferably, the seal 37 has the same width as the electronic circuit 25 so as to cover the entire face 28. For example, the seal 37 has a width of approximately 6 mm.

[0047] The shape of the seal 37 ensures, at the interface between the inner face 32 and the front face 27, a seal that isolates the sensors 29 from the external environment, namely the secondary channel 6 in which the measuring rake 1 is installed. Although the seal 37 provides a seal at the interface between the inner face 32 and the front face 27, it nevertheless allows fluid communication between the external environment and the sensors 29 through the air inlets 34. This fluid communication allows the airflow from the incident secondary channel 6 to enter the air inlets 34 so that the sensors 29 can measure pressure values ​​of said airflow.

[0048] The 37 seal corresponds to a flat seal made of a common waterproof material, preferably a silicone seal.

[0049] In particular embodiments, the measuring rake 1 may include a plurality of joints 37 covering all or part of the electronic circuit 25.

[0050] Furthermore, as depicted on the figure 6 The joint 37 has a plurality of openings 40 distributed along its length. The openings 40 extend through the faces 38 and 39 of the joint 37. Each opening 40 is located opposite each sensor 29 of the electronic circuit 25, thus forming cavities comprising each of said sensors 29. These cavities are closed, on one side, by the inner face 32 of the leading edge 31 and, on the other side, by the face 28 of the electronic circuit 25. The openings 40 then form cavities hermetically sealed from one another.

[0051] Furthermore, each air intake 34 of the leading edge attached 31 opens into one of the cavities formed by the openings 40. In this way, each sensor 29 is located in a sealed cavity which communicates with the outside through one of the air intakes 34.

[0052] Without limitation, the 40 openings may have a rectangular cross-section, for example, a 6 mm x 4 mm cross-section. The 40 openings are preferably made by laser cutting.

[0053] The seal 37 thus configured allows to obtain precise pressure measurements by reducing the risks of leaks or any obstruction of the air intakes 34. It allows, in particular, to obtain pressure measurements for each sensor 29 which are perfectly independent of each other.

[0054] Furthermore, as represented by the figure 4 to the figure 6 The measuring rake 1 has measuring tips 41 arranged on the outer face 33 of the attached leading edge 31. Each measuring tip 41 is located in the extension of an air intake 34. They have a hollow cylindrical shape, projecting towards the leading edge 23, and they are provided with an end 42 through which the incident airflow from the secondary vein 6 enters. Each measuring tip 41 is configured to channel the airflow from the secondary vein 6 into an air intake 34.

[0055] The measuring tips 41 correspond to standard Pitot tube-type tips. Preferably, they are Kiel probe-type tips adapted for total pressure measurements. In particular, Kiel probe-type tips allow for accurate measurements, to within 1%, for yaw and / or pitch angles of said measuring tip 41 up to 64° (relative to the direction of airflow).

[0056] Furthermore, the measuring tips 41 are made of metallic material. Preferably, they are made of stainless steel using three-dimensional printing.

[0057] In a particular embodiment, represented by the figure 4 to the figure 6 The measuring tips 41 are attached components that are removably fixed to the leading edge 31. To achieve this, the leading edge 31 has tapped holes 43 on its outer face 33. These holes are positioned on the outer face 33 such that an air inlet 34 opens into each of them. Furthermore, each measuring tip 41 has a threaded end 44, opposite the end 42, which is configured to be screwed into the tapped holes 43.

[0058] Thus, it is possible to easily change the measuring tips 41, for example to replace a defective tip or to change the type of tip with which one wishes to take measurements.

[0059] Furthermore, a flat gasket (not shown) can be fitted between the measuring tip 41 and the attached leading edge 31 to ensure a seal. In addition, or as an alternative, a thread-locking adhesive can be applied to the threaded end 44 to improve the fastening and / or sealing.

[0060] In addition, the measuring rake 1 includes fasteners suitable for removably fixing the leading edge 31 onto the sleeve 17. Without limitation, these fasteners may be screws, bolts or rivets.

[0061] In the preferred embodiment, represented by the figure 4 to the figure 6 , the measuring rake 1 includes a plurality of screws 45 and a counter plate 46 allowing the sleeve 17, the electronic circuit 25, the seal 37 and the leading edge 31 to be fixed together in a removable manner, as specified below.

[0062] The counter plate 46 is a rigid, elongated plate suitable for use as a mounting support for the measuring rake 1. It is arranged inside the sleeve 17, in the housing 19. Preferably, as shown in the figure 6 The counter plate 46 is slid into a T-shaped groove 56, which mechanically holds it in the sleeve 17 and provides access for inserting the screws 45. More specifically, the counter plate 46 has a face 47 arranged against a rear face 48 of the sleeve 17. The rear face 48 is located in a bay 49 at the bottom of the housing 19 parallel to the front face 27. The counter plate 46 also has a face 50 which serves as a bearing surface for the heads of the screws 45.

[0063] Furthermore, as depicted on the figure 6 The backing plate 46, the sleeve 17, the electronic circuit 25, and the gasket 37 are all drilled through by holes allowing the passage of screws 45. The backing plate 46 has through holes 51 between its faces 47 and 50. The sleeve 17 has holes 52 between its front face 27 and its rear face 48. The electronic circuit 25 has holes 53 between its faces 26 and 28. The gasket has holes 54 between its faces 38 and 39.

[0064] In addition, the attached leading edge 31 includes fixing holes 55 made in its inner face 32. These fixing holes 55 correspond to tapped holes, blind at one end and opening through the inner face 32 at the other end.

[0065] The backing plate 46, the electronic circuit 25, the gasket 37, and the attached leading edge 31 are arranged on the sleeve 17 so that the through holes 51, the holes 52, 53, 54, and the mounting holes 55 are aligned with each other. The sleeve 17 may have shapes adapted to achieve or facilitate this alignment. The screws 45 are arranged through the holes 51, 52, 53, 54, and 55 thus aligned so that their heads bear against the face 47 of the backing plate 46 and are screwed into the mounting holes 55 of the attached leading edge 31.

[0066] The measuring rake 1 thus mounted, as shown on the figure 6 , features a sandwich assembly held in position by screws 45. Such an assembly allows for several functions: It allows the attached leading edge 31 to be fixed to the sleeve 17; it allows the sandwiched elements to be positioned relative to each other thanks to the alignment achieved by means of the screws 45; and it allows the sandwiched elements, in particular the seal 37, to be tightened together so that it can ensure a seal.

[0067] In a preferred application, the measuring rake 1 as described above can be assembled and used as follows. The electronic circuit 25 is placed on the front face 27 of the sleeve 17. The gasket 37 is positioned over the electronic circuit 25 so as to position each sensor 29 of said electronic circuit 25 in one of the cavities formed by the openings 40. Simultaneously, the backing plate 46 is arranged against the rear face 48 of the sleeve 17 by being slid into the bay 49 by one of the ends 15 and 16 of the body 14 of said sleeve 17. The screws 45 are brought into the through holes 51 of the backing plate 46 from the recess 19 of the sleeve 17. Then, the positions of the backing plate 46, the electronic circuit 25, and the gasket 37 are adjusted so that the holes 51, 52, 53, and 54 align to allow the screws 45 to pass through.The attached leading edge 31 is then brought onto the front face 27 of the sleeve 17, over the electronic circuit 25 and the seal 37. The screws 45 are then screwed into the mounting holes 55 of the attached leading edge 31 by passing a screwing tool through the recess 19. In doing so, the screws 45 exert a force on the attached leading edge 31, which presses it against the front face 27 of the sleeve 17. The electronic circuit 25, the seal 37, and the sleeve 17 are then sandwiched between the backing plate 46 and the attached leading edge 31.

[0068] Once the measuring rake 1 is assembled, leak tests can be carried out to verify that the seal 37 is correctly positioned and that there are no leaks. Although this assembly greatly reduces the risk of leakage, if such a leak should be identified during the leak tests, the seal 37 can be repositioned by simply removing the attached leading edge 31.

[0069] The measuring rake 1, thus assembled and tested, is ready to be positioned on the connecting rod 12 of the engine 2 in which measurements are to be taken. Indeed, such an assembly without gluing does not require waiting for the glue to dry before performing leak tests and mounting the measuring rake 1 onto the connecting rod 12.

[0070] If a malfunction related to the electronic circuit 25 is detected (or even suspected), the measuring rake 1 is removed from the connecting rod 12 on which it is mounted. It is then disassembled by unscrewing the screws 45, which allows the leading edge 31 and the seal 37 to be removed, thus providing access to the electronic circuit 25. The defective sensor(s) 29 can then be identified and replaced, if necessary. Once this operation is complete, the measuring rake 1 is reassembled as described above and can be used again.

[0071] The measuring rake 1, as described above, offers many advantages. In particular: It features a simple and inexpensive design allowing for quick assembly; it avoids assembly by gluing and thus all the inherent problems, namely blockages of passages and / or leaks, which can impact measurements; it is assembled in a demountable manner which allows easy access to the electronic circuit 25; and it allows particular elements of the measuring rack to be replaced without having to replace the entire measuring rack 1, in particular to replace one or more defective sensors 29.

Claims

1. Measuring rake intended for arrangement on a link rod (12), said measuring rake comprising at least: - a sheath (17) comprising a front face (27) and two side walls (18A, 18B) which between them delimit a recess (19) intended for receiving the link rod (12); - an electronic circuit (25) arranged on the front face (27) of the sheath (17) and comprising at least one sensor (29); and - a patched leading edge (31) fixed removably to the sheath (17), said patched leading edge (31) comprising an inner face (32) arranged on the front face (27) of the sheath (17) so as to cover the electronic circuit (25), an outer face (33) situated opposite said inner face (32), and a plurality of air intakes (34) distributed over a length of the patched leading edge (31), each of said air intakes (34) forming a fluidic passage between the outer face (33) and the inner face (32) of the patched leading edge (31) opening out onto the electronic circuit (25) via said inner face (32), facing at least one sensor (29) of the electronic circuit (25).

2. Measuring rake according to Claim 1, characterized in that it additionally comprises at least one seal (37) arranged removably between the inner face (32) of the patched leading edge (31) and the front face (27) of the sheath (17), said seal (37) being pressed against the electronic circuit (25) while at least partially covering it.

3. Measuring rake according to Claim 2, characterized in that the seal (37) has at least one through-opening (40) facing at least one sensor (29) of the electronic circuit (25), each of said openings (40) forming, between the electronic circuit (25) and the inner face (32) of the patched leading edge (31), a cavity hermetically isolated from another cavity, each cavity comprising at least one sensor (29), each air intake (34) of the patched leading edge (31) communicating exclusively with one cavity.

4. Measuring rake according to any one of Claims 1 to 3, characterized in that the patched leading edge (31) comprises at least one measurement fitting (41) arranged on the outer face (33) of said patched leading edge (31) in the continuation of each air intake (34), each measurement fitting (41) having a cylindrical shape able to channel a flow of air incident on said outer face (33) into its respective air intake (34).

5. Measuring rake according to Claim 4, characterized in that the patched leading edge (31) comprises, on the outer face (33), at least one tapped hole (43) by way of which at least one air intake (34) opens out, each measurement fitting (41) corresponding to a fitted part screwed in a tapped hole (43).

6. Measuring rake according to any one of Claims 1 to 5, characterized in that it comprises at least one fixing element for fixing the patched leading edge (31) to the sheath (17).

7. Measuring rake according to Claim 6, characterized in that it additionally comprises at least one counter-plate (46) arranged on a rear face (48) of the sheath (17) situated opposite the front face (27), said counter-plate (46) being provided, over its length, with a plurality of through-holes (51) for the passage of the fixing elements from the inside of the sheath (17), said fixing elements passing through at least the counter-plate (46), the sheath (17), the seal (37) and the electronic circuit (25) to reach the patched leading edge (31) so as to fix said patched leading edge (31) to the sheath (17).

8. Measuring rake according to any one of the preceding claims, characterized in that it comprises at least one data processing unit (30) able to receive data measured by the sensors (29) of the electronic circuit (25), said data processing unit (30) being integrated in the sheath (17) or separate.

9. Engine for an aircraft, said engine (2) comprising a secondary duct (6) and at least one movable reverser door (10), said reverser door (10) comprising at least one link rod (12) fixed in articulated fashion between the reverser door (10) and a motor (8), said link rod (12) being configured to make it possible to bring the reverser door (10) into a retracted position, in which it is not across the secondary duct (6), and into a deployed position, in which it is across the secondary duct (6), characterized in that it comprises at least one measuring rake (1) according to any one of Claims 1 to 8, arranged on at least one link rod (12) of the engine (2), said one or more link rods (12) each being accommodated in the recess (19) of at least one measuring rake (1).

10. Aircraft, characterized in that it comprises at least one engine (2) according to Claim 9.