BLOWER MODULE BLADE LOCKING SYSTEM

Abstract

The present invention relates to a module (4) for an aircraft turbomachine test bench comprising a locking system (21) in position of the blade (12) comprising: - at least one pivot stop (23), and - at least two pivot flanges (24) arranged on either side of the pivot stop (23), and - at least two clamping members (27) passing through one of the annular elements (15.2) and each inserted inside a clamping hole made in a pivot flange (24) to ensure clamping of the blade pivot (13) between, on the one hand, the assembly formed by a pivot stop (23) and the two pivot flanges (24) and, on the other hand, said annular element (15.2) receiving the clamping members (27) so as to immobilize the blade (12) in a desired angular position. Figure 3

Description

Title of the invention: BLADE LOCKING SYSTEM OF A FAN MODULE

[0001] The present invention relates to a blade locking system for a fan module. The invention finds a particularly advantageous, but not exclusive, application with a fan rotor module.

[0002] In a manner known per se, a turbomachine fan compresses the air entering the engine. A large part of this air constitutes the secondary flow, and the other part constitutes the primary flow. The latter passes through a low-pressure compressor integral with 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 to a test machine for a test bench, in particular a fan of an aerodynamic demonstrator which has only a single air flow and which does not have a low pressure compressor, nor a high pressure compressor or a combustion chamber. The test machine aims to test different parts of the turbomachine and to optimize the operating settings of the turbomachine.

[0004] [Fig.l] shows a test machine 1 for a test bench comprising from upstream to downstream, an upstream flow vein 2, a fan 3 having a rotor module 4 with moving blades and a rectifier module 5 with fixed blades, as well as a downstream flow vein 6.

[0005] The rotor module 4 provides acceleration to the air particles, by deflecting them relative to the X axis of the engine. The rectifier module 5 slows down the air particles and transforms part of their speed into pressure. The rectifier module 5 brings the air flow, accelerated by the rotor module 4, back into the X axis of the engine.

[0006] During a test campaign, it is important to be able to ensure rapid assembly and disassembly of a blade as well as modification of its angular setting in order to find an optimum setting of the turbomachine. There is therefore a need to be able to carry out these operations as quickly as possible in order to limit the downtime of the test machine during a test campaign. These operations must also be able to be carried out without having to disassemble the test machine which is fully instrumented.

[0007] The invention aims to effectively meet the aforementioned needs by proposing a module for an aircraft turbomachine test bench comprising: - an annular hub comprising an upstream annular element and a coaxial downstream annular element fixed to each other and defining between them at least one pivot housing, - at least one blade associated with a blade pivot intended to be arranged inside the pivot housing, and - a blade position locking system comprising: - at least one pivot stop, and - at least two pivot flanges arranged on either side of the pivot stop, the two pivot flanges being mechanically linked to the pivot stop, and - at least two clamping members passing through one of the annular elements and each inserted inside a clamping hole made in a pivot flange to ensure clamping of the blade pivot between, on the one hand, the assembly formed by a pivot stop and the two pivot flanges and, on the other hand, said annular element receiving the clamping members so as to immobilize the blade in a desired angular position.

[0008] The invention thus makes it possible to easily modify the angular setting of the blade between two tests without having to dismantle the test machine. The invention makes it possible to limit downtime during the test as much as possible. The invention allows the adjustment of the blade setting while remaining in a dimensionally constrained environment. The invention also respects the aerodynamic profile of the vein regardless of the position of the blade, the vibrations, or its internal displacements due to pumping phenomena or transient flows during a change of setting. In the event of breakage of a blade, the invention also makes it possible to facilitate in situ disassembly. The invention also has the advantage of being a simple solution to implement containing a minimum of parts.

[0009] According to one embodiment of the invention, each pivot flange comprises two fixing holes intended to receive fixing members, so that a pivot flange provides a mechanical connection between two consecutive pivot stops.

[0010] According to one embodiment of the invention, the clamping members are constituted by clamping rods each inserted inside a through hole made in the annular element against which the blade pivot is clamped and a corresponding clamping hole made in a pivot flange as well as clamping nuts each screwed onto a corresponding clamping rod.

[0011] According to one embodiment of the invention, said module comprises at least two through windows made in the other annular element to access the tightening nuts.

[0012] According to one embodiment of the invention, a pivot stop has a contact face having a shape complementary to a portion of the blade pivot against which said pivot stop bears.

[0013] According to one embodiment of the invention, a pivot flange comprises a first bearing face having a shape complementary to a portion of a first blade pivot and a second bearing face having a shape complementary to a portion of a second blade pivot adjacent to the first blade pivot.

[0014] According to one embodiment of the invention, a portion of a pivot flange disposed between the first bearing face and the second bearing face comprises the clamping hole.

[0015] According to one embodiment of the invention, mounting rods of the annular hub are each inserted inside a first through mounting hole made in the upstream annular element and a second through mounting hole made in the downstream annular element.

[0016] According to one embodiment of the invention, an external face of the blade pivot is flush with a radially external face of the annular hub.

[0017] According to one embodiment of the invention, said module is constituted by a fan rotor module.

[0018] The present invention will be better understood and other characteristics and advantages will become apparent upon reading the detailed description which follows, comprising embodiments given by way of illustration with reference to the appended figures, presented as non-limiting examples, which may serve to complete the understanding of the present invention and the description of its embodiment and, where appropriate, contribute to its definition, in which:

[0019] [Fig-1] [Fig.l], already described, is a schematic view in longitudinal section of a test machine with which the invention is implemented;

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

[0021] [Fig.3] [Fig.3] is an exploded perspective view of a rotor module hub and of a blade locking system according to the present invention;

[0022] [Fig.4] [Fig.4] is a partial perspective view of a locking system of dawn according to the present invention;

[0023] [Fig.5] [Fig.5] is an axial sectional view illustrating the assembly of the elements annular rings of the hub as well as the mounting of a pivot flange of the blade locking system according to the present invention;

[0024] [Fig.6] [Fig.6] is a cross-sectional view illustrating the tightening of the system blade locking device according to the invention against a blade pivot;

[0025] [Fig.7] [Fig.7] is an axial sectional view of the blade pivot illustrating the forces applied by a pivot stop of the blade locking system according to the invention against a blade pivot;

[0026] [Fig-8] [Fig.8] is a partial front view illustrating through windows made in the upstream annular element to access clamping members of the blade locking system according to the invention.

[0027] It should be noted that the structural and / or functional elements common to the different embodiments have the same references from one figure to another. Thus, unless otherwise stated, such elements have identical structural, dimensional and material properties.

[0028] [Fig. 2] shows a rotor module 4, in particular for an aircraft turbomachine test bench, comprising an annular hub 11, also called a "fan disk" having an axis XI and a plurality of blades 12. The blades 12 extend radially outwards from the hub 11 along their axis Y. The blades 12 are distributed angularly in a regular manner along a circumference of the annular hub 11.

[0029] A blade 12 is secured to a corresponding blade pivot 13 of axis X2. The axis X2 may coincide with the axis Y of the blade 12. For this purpose, a blade 12 comprises a blade root inserted into a groove of complementary shape formed in a corresponding pivot 13. The complementary shapes of the blade root and the groove may in particular be dovetail shapes, hammer type, or fir tree root shapes, or any other shape suitable for the application. Alternatively, the blade 12 is integral with the blade pivot 13.

[0030] The annular hub 11 comprises two coaxial annular elements 15.1, 15.2 fixed to each other and defining between them housings 16 for receiving the pivots 13. A distinction is made, with reference to a direction of circulation of the air flow generated by the blower in operation, between an upstream annular element 15.1 and a downstream annular element 15.2. Thus, a pivot housing 16 is delimited by a portion of the upstream annular element 15.1 and a portion of the downstream annular element 15.2.

[0031] As can be seen in [Fig.7], the pivot housing 16 comprises an annular wall 19 originating from an internal periphery of said housing 16 against which a collar 20 of the blade pivot 13 bears. Advantageously, an external face of the blade pivot 13 is flush with a radially external face (relative to the axis XI) of the annular hub 11. This guarantees an optimum vein profile due to the continuity of the surface between the blade pivot 13 and the annular hub 11. This avoids any interference with the aerodynamic flow of the vein.

[0032] As can be seen in Figures 3, 4, 5 and 6, a locking system 21 in position of a blade 12 makes it possible, in an unlocked state, to authorize a rotation of the blade pivot 13 inside a corresponding pivot housing 16 around the axis of rotation X2 of the blade pivot 13, so as to select an angular position desired position of the blade 12 for testing and in a locked state to immobilize the blade 12 inside the pivot housing 16 in the desired angular position.

[0033] For this purpose, the locking system 21 comprises at least one pivot stop 23 and pivot flanges 24. A pivot stop 23 comprises two ears each provided with a fixing hole 26 receiving a fixing member for its fixing with two pivot flanges 24 described in more detail below. A pivot stop 23 has a contact face 37 having a shape complementary to a portion of the blade pivot 13 against which said pivot stop 23 bears.

[0034] At least two pivot flanges 24 are arranged on either side of a pivot stop 23. As can be seen in [Fig. 4], the two pivot flanges 24 are mechanically connected to the pivot stop 23. For this purpose, each pivot flange 24 has two fixing holes 25 intended to receive fixing members, so that a pivot flange 24 provides a mechanical connection between two consecutive pivot stops 23. A fixing hole 26 of a pivot stop 23 is arranged opposite a fixing hole 25 of an adjacent pivot flange 24. Along a circumference of the annular hub 11, there is an alternation of pivot stops 23 and pivot flanges 24, that is to say that one successively encounters a pivot stop 23 then a pivot flange 24 then a pivot stop 23 and so on along the circumference of the hub 11.

[0035] A pivot flange 24 comprises a first bearing face 38.1 having a shape complementary to a portion of a first blade pivot 13 and a second bearing face 38.2 having a shape complementary to a portion of a second blade pivot 13 adjacent to the first blade pivot 13. Thus, the first bearing face 38.1 of the pivot flange 24 is able to bear against the first blade pivot 13 and the second bearing face 38.2 of the pivot flange 24 is able to bear against a second blade pivot 13 adjacent to the first blade pivot 13. A pivot flange 24 therefore bears against a portion of two adjacent blade pivots 13.

[0036] A portion of a pivot flange 24 disposed between the first bearing face 38.1 and the second bearing face 38.2 comprises a clamping hole 33 intended to receive a clamping member 27 visible in FIGS. 3, 5 and 6.

[0037] Indeed, at least two clamping members 27 passing through the downstream annular element 15.2 are each inserted inside a clamping hole 33 made in a pivot flange 24 to ensure clamping of the blade pivot 13 between, on the one hand, the assembly formed by a pivot stop 23 and the two pivot flanges 24 and, on the other hand, said annular element 15.2 receiving the clamping members 27 so as to immobilize the blade 12 in a desired angular position.

[0038] Advantageously, the clamping members 27 are constituted by clamping tie rods each inserted inside a through hole 30 made in the downstream annular element. 15.2 against which the blade pivot 13 is clamped and a corresponding clamping hole 33 made in a pivot flange 24 as well as clamping nuts 34 each screwed onto a corresponding clamping tie rod 27.

[0039] As can be seen in [Fig.8], at least two through windows 35 are made in the other annular element 15.1 to access the tightening nuts 27. Each through window 35 opens axially, relative to the axis XI of the annular hub 11, on the one hand in an external face of the annular hub 11 and on the other hand opposite a tightening nut 34.

[0040] Mounting rods 40 of the annular hub 11 are each inserted inside a first through mounting hole 41.1 made in the upstream annular element 15.1 and a second through mounting hole 41.2 made in the downstream annular element 15.2, as shown in Figures 3 and 5. The mounting rods 40 are intended to cooperate with corresponding mounting nuts (not shown).

[0041] The operation of the locking system 21 according to the invention is described below. The blade pivots 13 are positioned in the housings of the downstream annular element 15.2. Each blade pivot 13 is held by two pivot flanges 24 and a corresponding pivot stop 23.

[0042] The centering of a blade pivot 13 is carried out both on the pivot flanges 24 and the downstream annular element 15.2 opposite the pivot flanges 24.

[0043] A pivot stop 23 is fixed to the two pivot flanges 24, for example using screws or any other fixing member suitable for the application. The pivot stop 23 radially blocks the corresponding blade pivot 13 against the upstream 15.1 and downstream 15.2 annular elements. [Fig. 7] thus shows that the pivot stop 23 applies an axial force F1 against the blade pivot 13 as well as a radial force F2, so that the collar 20 of the blade pivot 13 is pressed against the wall 19 formed in the annular elements 15.1, 15.2.

[0044] The pivot flanges 24 are fixed using the tightening rods 27 passing through the downstream annular element 15.2 and the corresponding tightening nuts 34.

[0045] The upstream annular element 15.1 is installed and clamped on the downstream annular element 15.2 to close the assembly by fixing the mounting tie rods 40 and the corresponding mounting nuts.

[0046] The angular position of the blades 12 is modified, as desired for the test, then the pivot flanges 24 are tightened by means of the tightening nuts 34 accessible via the through windows 35 made in the upstream annular element 15.1. The angular positioning of a blade pivot 13 is fixed by the tightening and friction of the pivot stop 23 and the pivot flanges 24 on the blade pivot 13.

[0047] In order to modify the angular position of a blade 12, the tightening nuts 34 are slightly loosened in order to be able to modify the inclination. blades 12 according to the desired angle. Once the angular positioning has been chosen, the clamping nuts 34 are tightened to immobilize the blade 12 in rotation during a test.

[0048] The operations of handling the blade 12 and tightening or loosening the fixing screws can be carried out by a human operator or automatically by a robot.

[0049] The invention thus makes it possible to quickly modify the setting of the blades 12 between two tests. The invention makes it possible to limit downtime during the test as much as possible. The invention allows the adjustment of the setting of the blade 12 while remaining in a dimensionally constrained environment. Furthermore, in the event of breakage of a blade 12, disassembly can be carried out in situ, which constitutes a significant time saving.

[0050] Alternatively, the module may be a fan rectifier module provided with a movable blade.

[0051] Of course, the various features, variants and / or embodiments of the present invention may be combined with each other in various combinations to the extent that they are not incompatible or mutually exclusive.

[0052] 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 may be envisaged by those skilled in the art within the scope of the present invention and in particular all combinations of the different operating modes described above, which may be taken separately or in association.

Claims

Claims

1. Module (4) for an aircraft turbomachine test bench comprising: - an annular hub (11) comprising an upstream annular element (15.1) and a downstream annular element (15.2) coaxially fixed to each other and defining between them at least one pivot housing (16), - at least one blade (12) associated with a blade pivot (13) intended to be arranged inside the pivot housing (16), characterized in that said module (4) further comprises a locking system (21) in position of the blade (12) comprising: - at least one pivot stop (23), and - at least two pivot flanges (24) arranged on either side of the pivot stop (23), the two pivot flanges (24) being mechanically linked to the pivot stop (23), and - at least two clamping members (27) passing through one of the annular elements (15.2) and each inserted inside a clamping hole (33) made in a pivot flange (24) to ensure clamping of the blade pivot (13) between, on the one hand, the assembly formed by a pivot stop (23) and the two pivot flanges (24) and, on the other hand, said annular element (15.2) receiving the clamping members (27) so as to immobilize the blade (12) in a desired angular position, - each pivot flange (24) has two fixing holes (25) intended to receive fixing members, so that a pivot flange (24) ensures a mechanical connection between two consecutive pivot stops (23).

2. Module according to claim 1, characterized in that the clamping members (27) consist of clamping rods each inserted inside a through hole (30) made in the annular element (15.2) against which the blade pivot (13) is clamped and a corresponding clamping hole (33) made in a pivot flange (24) as well as clamping nuts (34) each screwed onto a corresponding clamping rod.

3. Module according to claim 2, characterized in that it comprises at least two through windows (35) made in the other annular element (15.1) to access the tightening nuts (34).

4. Module according to any one of claims 1 to 3, characterized in that a pivot stop (23) has a contact face (37) having a shape complementary to a portion of the blade pivot (13) against which said pivot stop (23) bears.

5. Module according to any one of claims 1 to 4, characterized in that a pivot flange (24) comprises a first bearing face (38.1) having a shape complementary to a portion of a first blade pivot (13) and a second bearing face (38.2) having a shape complementary to a portion of a second blade pivot (13) adjacent to the first blade pivot (13).

6. Module according to claim 5, characterized in that a portion of a pivot flange (24) arranged between the first bearing face (38.1) and the second bearing face (38.2) comprises the clamping hole (33).

7. Module according to any one of claims 1 to 6, characterized in that mounting rods (40) of the annular hub (11) are each inserted inside a first through mounting hole (41.1) made in the upstream annular element (15.1) and a second through mounting hole (41.2) made in the downstream annular element (15.2).

8. Module according to any one of claims 1 to 7, characterized in that an external face of the blade pivot (13) is flush with a radially external face of the annular hub (11).

9. Module according to any one of claims 1 to 8, characterized in that it is constituted by a fan rotor module.

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