Unlockable wedging assembly for testing machine blade and associated wedging method

Abstract

Unlockable wedging assembly for a testing machine blade and associated wedging method One aspect of the invention relates to a wedging assembly (1) for a testing machine blade (3), comprising an annular support (7) which encloses a housing (15) for receiving the root (9) of the blade. This housing comprises in the outer part (16) at least one re-entrant return (17) which narrows it, and contains a wedging device (8) for said root. The wedging device comprises a fixed guide (23) with a radial threaded rod (27), a threaded wedging part (24) engaged with the threaded rod, which is movable by screwing / unscrewing along the threaded rod and which pushes the root into abutment against the re-entrant return when it moves outwards, and an actuating lever (25) whose pivoting causes the screwing / unscrewing of the wedging part onto the threaded rod. Figure to be published with the abstract: Figure 2

Description

Title of the invention: Unlockable wedging assembly for a testing machine blade and associated wedging method TECHNICAL FIELD OF THE INVENTION

[0001] The technical field of the invention is that of testing machines for the development of aircraft turbomachines.

[0002] The present invention relates to an unlockable wedging assembly for a turbomachine testing machine blade, preferably for a blade with adjustable angular orientation. It also relates to a turbomachine testing machine comprising such a wedging assembly, as well as a wedging method using such a wedging assembly. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] To develop and optimize the settings of aircraft turbomachines, it is common to use test machines. These test machines make it possible to test the aerodynamic and acoustic behavior of the various elements of the turbomachine and in particular to determine the optimal angular positioning of the moving blades of the rotors and the fixed blades of the stators to obtain the best possible performance.

[0004] These test machines conventionally comprise blades with adjustable angular orientation in order to be able to simulate a precise angular positioning of these blades and / or test different positions depending on the result of the tests, with a view to optimizing the air flow in the turbomachine.

[0005] These blades can be mounted on a fixed or rotating hub and thus belong to a stator or rotor stage. They can be, for example, the moving blades of the fan, the fixed flow straightening blades located downstream of the fan, called outlet guide vanes or OGV blades (Outlet guide vanes in English), or even the blades of the stator or rotor stages of the compressors.

[0006] Before a test session with the test machine, the angular positioning of these blades (their angle of attack) relative to the airflow passing through them must be adjusted while the test machine is stationary.

[0007] For this adjustment, these blades are first unlocked from their support, then pivoted around their axis until the desired angular position is reached. These blades must then be re-locked in position so that the chosen angular position is maintained during operation of the testing machine.

[0008] A wedging system, capable of holding these blades in position during operation of the testing machine and which is easily unlockable when stopped for allow their adjustment, is therefore necessary.

[0009] Currently, in testing machines, the blade setting is not designed to be unlockable. To carry out the angular adjustment, it is therefore necessary to manually dismantle the setting system for each of the blades, then once the adjustment has been made, reassemble it precisely without modifying the angular adjustment, while the assembly is difficult to access. This operation, which must be carried out blade by blade, is long, tedious and delicate.

[0010] An objective of the invention is to propose an alternative system for wedging the blades of a testing machine, which can be easily and quickly locked and unlocked, without dismantling the wedging system. Summary of the invention

[0011] A first aspect of the invention relates to a timing assembly for a blade of an X-axis turbomachine testing machine.

[0012] This wedging assembly includes: • a blade, comprising a root and a body extending radially from this root; • an annular support with axis X, which contains a housing in which the foot of the blade is received and which has on its external face an access opening to said housing through which the body passes, • a device for wedging the blade root located in said housing.

[0013] According to the invention, said housing comprises in the external part at least one re-entrant return which narrows the housing.

[0014] Furthermore, the wedging device comprises: • a threaded rod guide with a radial Y axis, said guide being fixed relative to the annular support; • a shim which comprises a threaded bore engaged with said threaded rod, the shim being movable along the threaded rod inwards by screwing and outwards by unscrewing the threaded bore on the threaded rod, and which when it moves outwards pushes the foot of the blade into abutment against the retracting return of the housing, • a lever for actuating the wedging part, integral with the wedging part and whose pivoting around the Y axis causes the threaded bore to be screwed or unscrewed onto the threaded rod.

[0015] In this application, two elements are said to be "integral" with each other if they are made from a single piece or are fixed to each other permanently or temporarily, so as to move together in a common movement. They can thus, for example, be single-piece or be welded, glued, screwed or clipped to each other.

[0016] The lever can thus be integral with the wedging part or be permanently fixed to it. It can also be removable and fixed to the wedging part, for example by screwing, just before carrying out the wedging or unlocking operation of the wedging assembly, and then be removed afterwards. The same lever can thus be used for several wedging assemblies.

[0017] Furthermore, screwing a tapped element onto a threaded element is defined as the movement which brings these two elements closer to each other and unscrewing is defined as the movement which moves these two elements away from each other.

[0018] Thanks to the wedging assembly of the invention, it is thus very easy and quick to obtain the wedging of the blade or its release by a simple pivoting of the actuating lever. Furthermore, it is not necessary to dismantle parts of the wedging assembly or the blade to achieve this.

[0019] Furthermore, with the wedging assembly according to the invention, the wedging device is housed in the annular support and no part of this device or any fixing element is located or protrudes into the air circulation vein of the testing machine. The wedging system therefore does not generate any disturbance of the aerodynamic flow.

[0020] Advantageously, the wedging part can be a nut.

[0021] Advantageously, the guide can be fixed to the internal wall of the housing.

[0022] Advantageously, the wedging assembly may further comprise a device for locking the actuating lever of the wedging part. This device locks the actuating lever in position, once the wedging has been carried out. It thus prevents vibrations from causing the lever to pivot, resulting in loosening of the wedging, during operation of the testing machine.

[0023] Advantageously, the lever may be a rod comprising a first end secured to the wedging part and a second end which protrudes from the housing through an opening in the annular support. The free end of the lever can thus be easily grasped and actuated, without having to open or dismantle the annular support.

[0024] Advantageously, the foot of the blade may comprise a cavity open towards the inside in which the wedging part and the threaded rod are housed. The wedging assembly according to the invention is thus particularly compact.

[0025] According to one embodiment, the access opening to the housing may be a slot going around the annular support, and the housing a U-shaped groove which goes around the annular support and which is narrowed in the outer part by two facing re-entrant returns. The housing is thus a collective housing in which the roots of all the blades of the relevant blade ring can be housed.

[0026] According to another embodiment, the annular support may comprise on its circumference a plurality of round openings giving access to a plurality of individual housings, each narrowed on the outside by a single circular re-entrant return. Each opening thus gives access to an individual housing in which is housed the foot of a single blade of the blade ring concerned.

[0027] Advantageously, the annular support may comprise an upstream part and a downstream part which are assembled to each other. The installation and assembly of the different elements of the wedging assembly are thus facilitated.

[0028] A second aspect of the invention relates to a turbomachine testing machine comprising at least one shimming assembly as described previously.

[0029] A third aspect of the invention relates to a method for setting a blade of an X-axis turbomachine test machine, carried out using a setting assembly as described previously and in which: • the actuating lever of the shim piece is pivoted in the direction causing the threaded bore on the threaded rod to unscrew until the foot of the blade is wedged between the shim piece and the retracting return of the housing.

[0030] This wedging process is therefore very easy and quick to implement and does not require any disassembly.

[0031] The unlocking of the wedging assembly is carried out very simply by a reverse movement of the actuating lever which, by causing the threaded bore to be screwed onto the threaded rod, releases the foot of the blade from the jamming constraint.

[0032] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0033] The figures are presented for information purposes only and in no way limit the invention.

[0034] [Fig.l] is a schematic sectional view of a portion of a testing machine according to an example of the invention.

[0035] [Fig.2] and [Fig.3] are schematic sectional views of an example of a set of wedging according to the invention, shown seen from the side in [Fig.2], and seen from above without the blade or the annular support in [Fig.3], this wedging assembly being in the locked position.

[0036] [Fig.4] and [Fig.5] are schematic sectional views corresponding respectively in [Fig.2] and [Fig.3], in which the wedging assembly is in the unlocked position. DETAILED DESCRIPTION

[0037] Unless otherwise specified, the same element appearing in different figures has a single reference.

[0038] In the present application, the terms "upstream" and "downstream" are defined with respect to the normal flow direction of gas (from upstream to downstream) through a turbomachine testing machine.

[0039] Also referred to as the "axis of the testing machine", the longitudinal axis of the testing machine corresponding to the axis of rotation of the rotor of this testing machine. This axis is referred to as X in the figures. The axial direction corresponds to the direction of this X axis and a radial direction is a direction perpendicular to the X axis and intersecting this axis. For example, the Y axis has a radial direction.

[0040] Unless otherwise specified, the adjectives “interior”, “internal”, “exterior”, “ "external" are used herein with reference to a radial direction, such that the inner part of an element is, in a radial direction, closer to the X axis than the outer part of the same element.

[0041] Furthermore, the expressions "top", "bottom", "upper", "lower" are defined with respect to the orientation of the parts as shown in the figures. It is obvious that this orientation will not necessarily be retained in use.

[0042] The figures show an example of a wedging assembly 1 according to the invention. This wedging assembly 1 is intended to be installed in a turbomachine test machine 2.

[0043] An example of a test machine 2 has been partially shown in [Fig.l]. Such a test machine 2 makes it possible to simulate an aircraft turbomachine and to test its components under different aerodynamic conditions in order to study their performance.

[0044] The test machine 2 comprises numerous blades 3 arranged in a succession of rings 4 of axis X, such as for example the fan 5 which is located furthest upstream and which is a ring of mobile blades 3, or the stator rectifier ring 6 which is arranged downstream of the fan 5 and which comprises blades 3 with adjustable orientation of the OGV type.

[0045] A shim assembly 1 is advantageously installed for each of these blades 3.

[0046] An example of a wedging assembly 1 has been more specifically shown in FIGS. 2 to 5. It comprises a blade 3, an annular support 7 of axis X and a wedging device 8.

[0047] The blade 3 comprises a root 9 which is extended by a body 11 forming, via a core 10 of smaller diameter, a curved blade 12 which extends outwards in a substantially radial general direction.

[0048] The annular support 7 has at its external face 13 an opening 14 giving access to a housing 15 contained inside the annular support 7 and intended to receive the root 9 of the blade 3. The blade 3 is thus engaged through this opening 14 and its root 9 housed in the housing 15.

[0049] In the example shown, the width of this housing 15 is narrowed in the outer part 16 (that is to say in the upper part according to the orientation shown) by two re-entrant returns 17 directed towards each other which engage in the narrowing 18 located at the level of the core 10, between the root 9 and the body 11 of the blade 3.

[0050] In this way, the re-entrant returns 17 ensure the centering of the foot 9 of the blade 3 in the housing 15, as well as its longitudinal retention.

[0051] The shape and number of the re-entrant returns 17 may be different depending on the variants. There may thus be a single re-entrant return 17, which preferably goes around the opening 14 in the manner of a peripheral rim, but which may also occupy only part of its perimeter.

[0052] There may also be several re-entrant returns 17, for example two, three or more, distributed around the opening 14 preferably regularly.

[0053] To avoid any possible biasing of the root 9 of the blade 3, the re-entrant return(s) 17 preferably form(s) a continuous stop which extends over more than half of the perimeter of the opening 14 or several discontinuous stops located on either side of the opening 14, for example at locations symmetrical with respect to a plane or an axis of symmetry of the opening 14 or at a regular angular arrangement around the opening 14.

[0054] According to the variants, the housing 15 may be an individual housing, for example substantially cylindrical, for the root 9 of a single blade 3, the annular support 7 then comprising a plurality of housings 15 over its entire circumference for all the blades 3 of a crown 4.

[0055] Alternatively, it may be a collective and continuous housing for all the feet 9 of the blades 3 of the crown 4. The opening 14 may then be, for example, a slot going around the annular support 7 and the housing 15 a U-shaped section groove whose outer part is narrowed by re-entrant returns 17, preferably in the form of two facing annular ribs.

[0056] In order to facilitate assembly, the annular support 7 is preferably made in two parts, an upstream part 19 and a downstream part 20, which are assembled to each other, for example by screwing, once the different elements of the assembly have been arranged.

[0057] In the example shown, the internal wall 21 forming the bottom of the housing 15 belongs to the upstream part 19 of the annular support 7. Depending on the variants, it can alternatively belong to the downstream part 20, or be made in two pieces, one belonging to the upstream part 19 and the other to the downstream part 20.

[0058] The wedging device 8 is also located in the housing 15 of the annular support 7, preferably interposed between the internal wall 21 and the root 9 of the blade 3. In the example shown, it is housed in a cavity 22, substantially cylindrical and open inwards (i.e. downwards), from foot 9 of blade 3.

[0059] This wedging device 8 comprises a guide 23, a wedging part 24 and a lever 25 for actuating the wedging part 24.

[0060] The guide 23 is fixed relative to the annular support 7 and to its housing 15. It comprises a support plate 26, for example circular, which is integral with the annular support 7. This support plate 26 is preferably placed on the internal wall 21 to which it is preferably fixed by screwing.

[0061] The guide 23 also comprises a threaded rod 27 with a radial axis Y, which starts from the support plate 26 and extends outwards.

[0062] The wedging part 24, which is preferably a bolt 28, comprises a tapped bore 29 which is engaged on the threaded rod 27 of the guide 23. The wedging part 24 thus moves along the threaded rod 27, downwards (inwards) if it is rotated in the screwing direction, and upwards (outwards) if it is rotated in the unscrewing direction.

[0063] When the wedging part 24 moves upwards (outwards), it comes to bear against the root 9 of the blade 3, then, if its movement continues, pushes it upwards (outwards) until the root 9 is in abutment against the re-entrant returns 17.

[0064] The lever 25 is integral with the wedging part 24 and makes it possible to drive the wedging part 24 in screwing or unscrewing rotation on the threaded rod 27, by pivoting the lever 25 around the Y axis.

[0065] In the example shown, this lever 25 is a rod of which a first end 30 is made in one piece with or fixed to the wedging part 24 and of which a second end 31 protrudes from the housing 15 through an opening 32 of the annular support 7 and makes it possible to actuate the lever 25.

[0066] When the wedging part 24 is located in a cavity 22 of the root 9 of the blade 3, an opening 33 is also provided in the root 9 so that the lever 25 can pass through it.

[0067] The openings 32 and 33 have sufficient dimensions to allow the movement of the lever 25 and the displacement of the wedging part 24.

[0068] However, the movement of the lever 25 remains limited, because an angular displacement of less than a quarter turn is generally sufficient to achieve the wedging, the amplitude of the necessary angular displacement depending on the pitch chosen for the thread of the threaded rod 27. In fact, the larger the pitch, the greater the radial displacement of the wedging part 24 for the same angular displacement of the lever 25.

[0069] The method of wedging using the wedging assembly 1 results from the means described above.

[0070] To wedge the foot 9 of the blade 3 in the housing 15, it is sufficient to grasp the end 31 of the lever 25 and to pivot the lever 25 around the Y axis to cause the unscrewing of the tapped bore 29 on the threaded rod 27. By this movement, the wedging part 24 moves upwards (outwards) along the threaded rod 27 and comes to bear against the root 9 of the blade 3 which it pushes upwards (outwards).

[0071] The lever 25 is continued to be actuated until the root 9 of the blade 3 is in abutment against the re-entrant returns 17. The root 9 is then wedged between the wedging part 24 and the re-entrant returns 17 as illustrated in FIGS. 2 and 3. Wedging of the blade 3 is thus obtained by wedging its root 9 with a force that is all the greater as the screwing is tight. In this configuration, pivoting of the blade 3 is impossible.

[0072] The wedging assembly 1 according to the invention is thus perfectly capable of holding the blades in position during operation of the test machine 2, despite the aerodynamic forces to which the blades 3 are subjected. On the contrary, the wedging is further improved by the centrifugal force which is exerted on the blades during their rotation and which tends to press the roots 9 even more against the re-entrant returns 17.

[0073] Optionally, the assembly can be completed by a lever locking device 25 which locks the lever in position, once the foot 9 has been jammed. Such a device advantageously makes it possible to avoid the assembly becoming loose due to vibrations during operation of the testing machine.

[0074] Unlocking the wedging assembly is easily done by proceeding in reverse order.

[0075] It is sufficient to grasp the end 31 of the lever 25 and pivot it around the axis Y in the direction causing the threaded bore 29 to unscrew on the threaded rod 27. By this movement, the wedging part 24 moves downwards (inwards) along the threaded rod 27 and releases the root 9 from its jamming against the re-entrant returns 17. The wedging assembly 1 is then unlocked as illustrated in FIGS. 4 and 5. The blade 3, released from the constraint at its root 9, is then no longer wedged and can, for example, be pivoted to modify its angular orientation.

[0076] Thanks to the wedging assembly 1 according to the invention, it is possible to adjust the angular orientation of the blade 12 very simply and quickly.

[0077] Indeed, it is sufficient to remove the cover (if there is one) giving access to the free end 31 of the lever 25 and to pivot the lever 25 to obtain the unlocking of the wedging assembly 1 without having to remove it.

[0078] The angular position of the blade 3 can then be freely modified until the desired final position for the blade 12 is obtained.

[0079] It is then sufficient to pivot the lever 25 in the opposite direction to again wedge the root 9 of the blade 3 and obtain the setting of the blade 3 in the desired angular position. The hood is then closed and the testing machine 2 can be used.

Claims

Claims

1. Wedging assembly (1) of a blade (3) of an X-axis turbomachine testing machine (2), said wedging assembly comprising: - a blade (3), comprising a foot (9) and a body (11) extending radially from this foot; - an annular support (7) of axis X, which contains a housing (15) in which the root (9) of the blade (3) is received and which has on its external face an opening (14) for access to said housing (15) through which the body (11) passes, - a device (8) for wedging the foot (9) of the blade (3) located in said housing (15), - wedging assembly (1) characterized in that said housing (15) comprises in the outer part (16) at least one re-entrant return (17) which narrows the housing (15), and - in that the wedging device (8) comprises: • a guide (23) with a threaded rod (27) with a radial Y axis, said guide (23) being fixed relative to the annular support (7); • a wedging part (24) which comprises a threaded bore (29) engaged with said threaded rod (27), the wedging part (24) being movable along the threaded rod (27) inwards by screwing and outwards by unscrewing the threaded bore (29) on the threaded rod (27), and which when it moves outwards pushes the root (9) of the blade (3) into abutment against the retracting return (17) of the housing (15), • a lever (25) for actuating the wedging part (24), integral with the wedging part (24) and whose pivoting around the radial Y axis causes the threaded bore (29) to be screwed or unscrewed onto the threaded rod (27).

2. Wedging assembly (1) according to claim 1 characterized in that the shim (24) is a nut (28).

3. Wedging assembly (1) according to one of the preceding claims, characterized in that it further comprises a device for locking the lever (25) for actuating the wedging part (24).

4. Wedging assembly (1) according to one of the preceding claims, characterized in that the actuating lever (25) is a rod comprising a first end (30) integral with the wedging part (24) and a second end (31) which protrudes from the housing (15) through an opening (32) in the annular support (17).

5. Wedging assembly (1) according to one of the preceding claims, characterized in that the root (9) of the blade (3) comprises a cavity (22) open towards the inside in which the wedging part (24) and the threaded rod (27) are housed.

6. Wedging assembly (1) according to one of the preceding claims, characterized in that the opening (14) for access to the housing (15) is a slot going around the annular support (7), and the housing (15) is a U-shaped groove which goes around the annular support (7) and which is narrowed in the outer part (16) by two facing re-entrant returns (17).

7. Wedging assembly (1) according to one of claims 1 to 5, characterized in that the annular support (7) comprises on its circumference a plurality of round openings (14) giving access to a plurality of individual housings (15), each narrowed in the outer part (16) by a single circular re-entrant return (17).

8. Wedging assembly (1) according to one of the preceding claims, characterized in that the annular support (7) comprises an upstream part (19) and a downstream part (20) which are assembled to each other.

9. Turbomachine testing machine (2) characterized in that it comprises at least one shimming assembly (1) according to one of the preceding claims.

10. Method for wedging a blade (6) of a testing machine (2) of an X-axis turbomachine, characterized in that it is carried out by means of a wedging assembly (1) according to one of claims 1 to 8 and in which the lever (25) for actuating the wedging part (24) is pivoted in the direction causing the unscrewing of the tapped bore (29) on the threaded rod (27) until the root (9) of the blade (3) is wedged between the wedging part (24) and the retracting return (17) of the housing (15).

Images