System for adjusting the rotational pitch of a blower module blade via an external screw

Abstract

The invention relates to an aircraft turbomachine module, particularly for a test bench, comprising: - an annular hub (10), - at least one blade (11), and - a rotational adjustment system (17) for the blade (11) comprising: - an adjusting screw (19) having one end screwed into a tapped bore (20) made in the blade root (13), such that the adjusting screw (19) is rotationally linked to the blade root (13), - a flange (21) fixed to one face of the annular hub (10), such that loosening the adjusting screw (19) allows angular movement of the blade (11) along the oblong opening (23) of the flange (21) so as to allow selection of a desired angular position, and tightening the adjusting screw (19) allows the blade (11) to be fixed in the desired angular position. Figure 3

Description

Title of the invention: SYSTEM FOR ADJUSTING THE ROTATIONAL ADJUSTMENT OF A BLADE OF A BLOWER MODULE BY AN EXTERNAL SCREW

[0001] The present invention relates to a system for adjusting the rotation of a blower module blade by means of an external screw. The invention finds a particularly advantageous, but not exclusive, application with a blower rectifier module.

[0002] The operating principle of a turbomachine fan is to compress the air entering the engine. Part of this air constitutes the primary flow, delimited by a primary stream, and another part of this air constitutes the secondary flow, delimited by a secondary stream. The primary flow passes through a low-pressure compressor attached to the fan, through a high-pressure compressor, through the combustion chamber, through the high-pressure turbine, and finally through the low-pressure turbine before being ejected.

[0003] The present invention relates in particular to a test machine for a test bench, for example, a blower of an aerodynamic demonstrator that has only a single airflow and does not have a low-pressure compressor, a high-pressure compressor, or a combustion chamber. Such a test machine is intended to test different parts of the turbomachine and to optimize the operating settings of the turbomachine.

[0004] Fig. 1 shows a test machine 1 for a test bench comprising, from upstream to downstream, an upstream flow channel 2, a blower 3 having a rotor module 4 with moving blades and a straightener module 5 with fixed blades called OGV (for "Outlet Guide Vane" in English), as well as a downstream flow channel 6.

[0005] The rotor module 4 comprises a plurality of blades mounted on a cylindrical hub called a "fan disk," which is rotated by a pressure turbine supplied with air by the test bench. The rotor module 4 accelerates the air particles by deflecting them from the X-axis of the motor. The rectifier module 5 slows the air particles and converts some of their velocity into pressure. The rectifier module 5 then returns the airflow, accelerated by the rotor module 4, to the X-axis of the motor.

[0006] During a test campaign, it is important to be able to quickly assemble and disassemble a blade and adjust its angular position to find the optimal setting for the turbomachine. Therefore, these operations must be performed as quickly as possible to minimize downtime of the test machine during the campaign. These operations must also be able to be carried out without having to dismantle the test machine which is fully instrumented.

[0007] The invention aims to effectively meet the aforementioned needs by proposing an aircraft turbomachine module, particularly for a test bench, comprising: - an annular hub comprising at least one blade foot housing, - at least one blade fitted with a blade foot intended to be placed inside the blade foot housing, said blade having an axis, - a blade rotation adjustment system comprising: - an adjusting screw having one end screwed into a tapped bore made in the blade root, so that the adjusting screw is rotationally bound to the blade root, - a flange fixed to one face of the annular hub, said flange having an oblong opening, - the adjusting screw being inserted inside the oblong opening of the flange and a through window made in the wall of the hub, so that loosening the adjusting screw allows an angular movement of the blade along the oblong opening of the flange so as to be able to choose a desired angular position, and tightening the adjusting screw makes it possible to immobilize the blade in the desired angular position.

[0008] The invention thus makes it possible to easily modify the angular position of the blade between two tests without having to dismantle the test machine. The invention minimizes downtime during testing. The invention allows for blade position adjustment while remaining within a dimensionally constrained environment. The invention also preserves the aerodynamic profile of the flow regardless of the blade's position, vibrations, or internal displacements due to pumping or transient flow phenomena during a position change. In the event of blade breakage, the invention further facilitates in-situ dismantling. The invention also has the advantage of being a simple solution to implement, requiring a minimum number of parts.

[0009] According to one embodiment of the invention, the adjusting screw has a radial orientation with respect to an axis of the blade.

[0010] According to one embodiment of the invention, the adjusting screw is associated with a washer.

[0011] According to one embodiment of the invention, the flange has a convex shape and the The washer has a complementary concave shape.

[0012] According to one embodiment of the invention, the convex flange and the concave washer have a radius of curvature having one end passing through the axis of the blade.

[0013] According to one embodiment of the invention, the flange has two fixing lugs intended to receive each a fixing member to fix the flange on the annular hub.

[0014] According to one embodiment of the invention, the assembly formed by a head of the adjusting screw, the washer and the flange is arranged inside a housing located under a vein of the module.

[0015] According to one embodiment of the invention, said module includes an access cover recreating the vein allowing access to the adjusting screw to modify an angular position of the blade.

[0016] According to one embodiment of the invention, the annular hub is a one-piece hub.

[0017] According to one embodiment of the invention, the module is a rectifier module.

[0018] The present invention will be better understood and other features and advantages will become apparent upon reading the following detailed description, which includes embodiments given by way of illustration with reference to the accompanying figures, presented by way of non-limiting examples, which may serve to complete the understanding of the present invention and the explanation of its implementation and, where appropriate, contribute to its definition, on which:

[0019] [Fig-1] Fig. 1, already described, is a longitudinal cross-sectional view of a machine test with which the invention is implemented;

[0020] [Fig.2] Fig.2 is a perspective view of a rectifier module for a bench aircraft turbomachine test according to the present invention;

[0021] [Fig. 3] Fig. 3 is a schematic cross-sectional view of a blade and a system of rotation adjustment of a blade according to the invention;

[0022] [Fig.4] Fig.4 is a detailed cross-sectional view of a paddle foot and a system of rotation adjustment of a blade according to the invention;

[0023] [Fig. 5] Fig. 5 is a detailed perspective view of an adjustment system. rotation of a blade according to the invention;

[0024] [Fig. 6a] [Fig. 6b] Figures 6a and 6b are top views illustrating two positions angular angles that can be taken by a blade thanks to the blade rotation adjustment system according to the invention.

[0025] It should be noted that in the figures, the structural and / or functional elements common to the different embodiments have the same reference numerals. Thus, unless otherwise stated, such elements have identical structural, dimensional and material properties.

[0026] Figure 2 shows a rectifier module 5 for a turbomachine test bench aircraft comprising an annular hub 10 having an axis XI and a plurality of blades 11.

[0027] The annular hub 10 comprises a plurality of blade root housings 12. Advantageously, the annular hub 10 is a single-piece hub. Alternatively, the annular hub 10 can be formed by two coaxial annular elements fixed to each other and defining between them the blade root housings 12 11.

[0028] The blades 11 extend radially along their Y-axis outwards from the hub 10. The blades 11 are regularly spaced angularly around a circumference of the hub 10. Each blade 11 is provided with a generally cylindrical blade foot 13 intended to be positioned inside a corresponding blade foot housing 12. A large-diameter portion of the blade foot 13 can bear against a shoulder 15 of the housing 12 designed to provide radial retention of the blade foot 13 with respect to the axis XI, as shown in [Fig. 4].

[0029] A blade rotation adjustment system 17 allows, in an unlocked state, a rotation of the blade foot 13 inside a corresponding housing 12 around the Y axis so as to select a desired angular position of the blade 11 for a test and, in a locked state, to immobilize the blade 11 inside the housing 12 in the desired angular position.

[0030] For this purpose, as illustrated in figures 3, 4, and 5, the rotation adjustment system 17 of the blade 11 includes an adjusting screw 19 cooperating with a flange 21 by means of a washer 25 disposed between the head of the adjusting screw 19 and the flange 21.

[0031] More specifically, the adjusting screw 19 has one end screwed into a tapped bore 20 made in the blade foot 13, so that the adjusting screw 19 is rotationally linked with the blade foot 13. The adjusting screw 19 has a radial orientation with respect to a Y axis of the blade 11. The adjusting screw 19 is preferably associated with a washer 25.

[0032] The flange 21 is fixed to a face of the annular hub 10. In this case, the flange 21 is fixed to an axial end face of the annular hub 10. For this purpose, as can be seen in [Fig. 5], the flange 21 has two fixing lugs 27 intended to receive each a fixing member for fixing the flange 21 to the annular hub 10. The fixing members can be in the form of a screw, a rivet or any other fixing member suitable for the application.

[0033] As can be seen in Figures 5, 6a and 6b, the flange 21 has an oblong opening 23. The adjusting screw 19 is inserted inside the oblong opening 23 of the flange 21 and a through window 24 made in the wall of the hub 10. The through window 24 opens on one side into the blade foot housing 12 opposite the tapped bore 20 and on the other side into an end face of the hub 10. A width L1 of the through window 24 is substantially equal to a length L2 of the oblong opening of the flange 21, as shown in [Fig. 6a].

[0034] Advantageously, the flange 21 has a convex shape and the washer 25 has a complementary concave shape. The convex flange 21 and the concave washer 25 have a radius of curvature Rc having one end passing through the Y-axis of the blade 11.

[0035] The operation of the adjustment system 17 in rotation according to the invention is described below.

[0036] As illustrated in Figures 6a and 6b, loosening the adjusting screw 19 allows angular movement of the blade 11 along the oblong opening 23 of the flange 21 so as to allow selection of a desired angular position. The angular movement of the blade 11 is performed around an axis of rotation corresponding to the Y-axis of the blade 11 or an axis of the blade root 13, the two axes being able to coincide.

[0037] When the blade 11 is in the desired angular position, tightening the adjusting screw 19 against the flange 21 via the washer 25 secures the blade 11 in this angular position. It is then possible to test the blower with this stator module configuration. Alternatively, the washer 25 is omitted so that the adjusting screw 19 is tightened directly against the flange 21 to hold the blade 11 in the desired angular position.

[0038] The operations of manipulating the blade 11 and tightening or loosening the adjusting screw 19 can be carried out by a human operator or automatically by a robot.

[0039] The invention thus allows for a rapid adjustment of the blade alignment 11 between two tests. The invention minimizes downtime during testing. The invention allows for blade alignment adjustment while remaining within a dimensionally constrained environment. Furthermore, in the event of blade breakage 11, disassembly can be carried out in situ, resulting in significant time savings.

[0040] The assembly formed by a head of the adjusting screw 19, the washer 25 and the flange 21 is arranged inside a housing located under a vein of the blower module.

[0041] An access cover 28 recreating the duct allows access to the adjustment screw 19 to modify an angular position of the blade 11. This ensures an optimum duct profile due to the continuity of the surface between the blade foot and the hub 10. This avoids any interference with the aerodynamic flow of the duct.

[0042] The invention respects the aerodynamic profile of the duct regardless of the position of the blade, vibrations, or its internal displacements due to pumping phenomena or transient flow during a change of pitch.

[0043] The invention guarantees mechanical strength of the parts and assembly at all operating regimes of the turbomachine.

[0044] The invention also has the advantage of being a simple solution to implement containing a minimum of parts.

[0045] Alternatively, the blower module 5 can be a rotor module.

[0046] Of course, the different features, variants and / or embodiments of the present invention can be combined with each other in various ways, provided they are not incompatible or mutually exclusive. from others.

[0047] Furthermore, the invention is not limited to the embodiments described above and provided solely by way of example. It encompasses various modifications, alternative forms, and other variants that a person skilled in the art may consider within the scope of the present invention, and in particular all combinations of the different modes of operation described above, which may be taken separately or in combination.

Claims

Claims

1. Aircraft turbomachine module (5), in particular for a test bench, comprising: - an annular hub (10) comprising at least one blade root housing (12), - at least one blade (11) provided with a blade root (13) intended to be arranged inside the blade root housing (12), said blade (11) having an axis (Y), characterized in that said module (5) comprises a system (17) for adjusting the rotation of the blade (11) comprising: - an adjusting screw (19) having one end screwed into a tapped bore (20) made in the blade root (13), so that the adjusting screw (19) is linked in rotation with the blade root (13), - a flange (21) fixed on a face of the annular hub (10), said flange (21) comprising an oblong opening (23), - the adjusting screw (19) being inserted inside the oblong opening (23) of the flange (21) and a through window (24) made in the wall of the hub (10),so that loosening the adjusting screw (19) allows angular movement of the blade (11) along the oblong opening (23) of the flange (21) so as to be able to choose a desired angular position, and tightening the adjusting screw (19) allows the blade (11) to be immobilized in the desired angular position.,

2. Module according to claim 1, characterized in that the adjusting screw (19) has a radial orientation relative to the axis (Y) of the blade (H).

3. Module according to claim 1 or 2, characterized in that the adjusting screw (19) is associated with a washer (25).

4. Module according to claim 3, characterized in that the flange (21) has a convex shape and the washer (25) has a complementary concave shape.

5. Module according to claim 4, characterized in that the convex flange (21) and the concave washer (25) have a radius of curvature (Rc) having one end passing through the axis of the blade (11).

6. Module according to any one of claims 1 to 5, characterized in that the flange (21) comprises two fixing lugs (27) each intended to receive a fixing member for fixing the flange (21) to the annular hub (10).

7. Module according to any one of claims 1 to 6, characterized in that the assembly formed by a head of the adjustment screw (19), the washer (25) and the flange (21) is arranged inside a housing located under a vein of the module.

8. Module according to claim 7, characterized in that it comprises an access cover (28) reconstituting the vein allowing access to the adjustment screw (19) to modify an angular position of the blade (11).

9. Module according to any one of claims 1 to 8, characterized in that the annular hub (10) is a single-piece hub.

10. Module according to any one of claims 1 to 9, characterized in that the module is a rectifier module (5).

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