KIT FOR TURBOMACHINE AND ASSOCIATED TURBOMACHINE

Abstract

Assembly for a turbomachine comprising a central axis (C), in particular for an aircraft, the assembly comprising:- an injection system (48) comprising at least one annular swirler (54) with a central axis (C) comprising an annular row of blades (62, 62-1, 62-2) mounted to be movable in rotation about a respective axis of rotation between a first position and a second position, an air passage section in said annular swirler (54, 54-1, 54-2) being smaller in the first position than in the second position of the blades; and- a rotary member (68) with a central axis (C) coupled in rotation to said annular row of blades (62, 62-1, 62-2) so as to simultaneously move in rotation the blades (62, 62-1, 62-2) of said annular row of blades (62, 62-1, 62-2) between the first position and the second position when said rotary member (68) is rotated. Abstract figure: Figure 2

Description

Title of the invention: ASSEMBLY FOR TURBOMACHINE AND ASSOCIATED TURBOMACHINE Technical field

[0001] The present disclosure relates to a turbomachine assembly and an associated turbomachine. The turbomachine is in particular a turbomachine for aircraft. Prior art

[0002] In a known manner, an aircraft is propelled from turbomachines, for example turbojets or turboprops, shaped to receive an airflow at an upstream end. In the case of turbojets, this airflow is expelled at high speed at the rear end of the turbomachine to create the necessary thrust which moves the aircraft forward. In the case of turboprops, this airflow turns a turbine located at the rear of the turbomachine, which rotates a propeller located at the upstream end of the turbomachine. It is mainly the rotation of this propeller which creates the thrust which moves the aircraft forward when it uses turboprops.

[0003] A portion of the airflow received in each turbomachine is compressed in low-pressure and high-pressure compressors of the turbomachine, then passes through a combustion chamber installed therein. The combustion chamber typically has an annular shape around an axis of revolution and comprises a plurality of openings arranged regularly around this axis of revolution.

[0004] An injection system is arranged in each opening of the combustion chamber. Conventionally, the injection system comprises a mixing bowl and at least one swirler arranged around a central axis of the injection system. The injection system is configured to introduce a portion of the compressed air flow into the combustion chamber. In order to ensure the permeability of the injection system to compressed air, the injection system comprises through holes arranged circumferentially around its central axis, for example on the swirler and / or on the mixing bowl.

[0005] The injection system further comprises a cavity extending around the central axis and in which is received a head of a fuel injector which injects a flow of fuel into the combustion chamber. The injected flow of fuel is sprayed and atomized by the flow of compressed air introduced by the air injection system, which gives rise to a mixture of air and fuel.

[0006] The turbomachine has several operating modes or phases, such as ignition, re-ignition, ground idle, takeoff, flight idle or cruise. During the ignition or re-ignition phases of the turbomachine, the air-fuel mixture is ignited by means of a spark plug in the combustion chamber. Conversely, during the ground idle, takeoff, flight idle or cruise phases of the turbomachine, the spark plug does not operate because combustion is maintained. The flame created during the ignition or re-ignition phases is in fact maintained by the supply of compressed air and fuel coming, respectively, from the air injection system and the injector head.

[0007] It should be noted that the conditions for relighting the turbomachine are critical. Indeed, the relighting of the turbomachine occurs when the flame in the combustion chamber goes out while the aircraft is in flight. Consequently, the low pressure and low temperature of the ambient air, the low temperature of the injected fuel, the variations in the viscosity of the fuel, and the high flow speed of the air in the combustion chamber constitute difficult conditions for relighting the combustion chamber that has gone out. A relight ceiling for the turbomachine is thus defined, which corresponds to the maximum altitude above sea level over a certain speed range of the aircraft at which the combustion chamber can be relighted. Guaranteeing the relight ceiling specified by the aircraft manufacturer can be a significant technical challenge for the engine manufacturer.

[0008] During these ignition and re-ignition phases, it may appear that the flame kernel initiated in front of the spark plug has difficulty reaching the fuel recirculation zone of the injection system or that the flame stagnates in front of an injection system without propagating to neighboring injection systems, which leads to a failure of ignition of the combustion chamber.

[0009] To improve this situation, it is known to permanently reduce the permeability of the injection systems, in particular by reducing the size of the through holes provided in the injection system. However, reducing the permeability of the injection systems degrades the high-speed efficiency of the turbomachine and increases pollutant emissions. Summary

[0010] The present disclosure improves the situation.

[0011] For this purpose, there is proposed an assembly for a turbomachine comprising a central axis, in particular for an aircraft, the assembly comprising: - an injection system for a combustion chamber of the turbomachine, the injection system extending around said central axis, the injection system comprising at least one annular swirler with a central axis comprising an annular row of blades mounted to be movable in rotation around a respective axis of rotation between a first position and a second position, an air passage section in said annular swirler being smaller in the first position than in the second position of the blades; and - a central axis rotary member coupled in rotation to said annular row of blades so as to simultaneously move in rotation the blades of said annular row of blades between the first position and the second position when said rotary member is rotated.

[0012] The rotation of the rotary member, which is advantageously carried out around the central axis, thus makes it possible to modify the position of the set of blades so as to increase or reduce the air passage section in the at least one swirler. This modification of the position of the blades implies that the timing of the at least one swirler is modified. The timing of the swirler can thus be adjusted according to the operating speed of the turbomachine in which the assembly is installed, which makes it possible to improve the performance of the turbomachine according to the speed in which it operates. The performance of the turbomachine can, for example, be improved in terms of fuel consumption, re-ignition ceiling, stability of the combustion chamber of the turbomachine, flame blowing limit in the combustion chamber or emission of pollutants.

[0013] The pitch is defined here as the angle formed between a radial direction passing through the radially outer edge of a blade and a direction tangent to the surface of this blade.

[0014] Generally, the assembly is configured so that the pitch decreases when the blades move from the first position to the second position, and so that the pitch increases when the blades move from the second position to the first position.

[0015] According to the invention, each blade can remain in any position between the first position and the second position. This, apart from allowing the timing of each swirler to be finely adapted to the operating speed of the turbomachine, allows the assembly to be used as test equipment in order to determine experimentally, with a single injection system, what is the optimal timing of each swirler as a function of the operating speed of the turbomachine. Indeed, thanks to this assembly, it is possible to scan all possible timing angles during partial development tests or complete chamber tests (or even engine tests) in order to find the best compromise on this parameter, and this with a single test specimen. It is thus possible to save time in assembling / disassembling the assembly, as well as to reduce the number of test specimens to be produced.

[0016] Furthermore, the passage from the first position to the second position of the blades modifying the air passage section in the swirler, the permeability of the injection system of the assembly can be modified according to the operating regime. of the turbomachine. For example, during the ignition or re-ignition phase, it is advantageous to reduce the permeability of the injection system in order to enrich the combustion chamber with fuel. Also, during the ignition or re-ignition phases, it is advantageous for the blades to move from the second position to the first position. On the contrary, when the turbomachine is operating at full throttle, for example during the take-off phase, it is advantageous to increase the permeability of the injection system to impoverish the combustion chamber with fuel in order to reduce pollutant emissions. In full throttle regimes, it is therefore advantageous for the blades to move from the first position to the second position.

[0017] In the present text, by "axial" or "longitudinal" is meant "substantially parallel to the central axis of the assembly", while by "radial" is meant "substantially perpendicular to the central axis of the assembly".

[0018] According to one aspect, each blade of the annular row of blades is integral with a respective rod individually connected to the rotating member by a connecting rod mechanism.

[0019] Thanks to the connecting rod mechanism, the rod can rotate in solidarity with the rotating member, thus driving the blade to which it is connected in rotation. The timing of the spinner can thus be modified.

[0020] Each rod extends for example along the axis of rotation of the blade to which it is connected and is mounted to be able to rotate in solidarity with the respective blade about this axis of rotation. Also, when the rotary member is driven in rotation about the central axis, each rod rotates about the axis of rotation of the respective blade, and the latter also rotates about its axis of rotation.

[0021] According to one example, a portion of the rod is mounted tightly in the respective blade, thus making it possible to secure the rotational movement of each blade-rod pair.

[0022] According to the invention, each rod may have a substantially cylindrical shape, without this being limiting.

[0023] According to one aspect, each connecting rod mechanism comprises a lug, a first end of which is secured to a first end of the rod and a second end of which opposite said first end is capable of being driven in rotation about a longitudinal axis of the rod during rotation of the rotary member.

[0024] The longitudinal axis of the rod advantageously corresponds to the axis of rotation of the blade to which it is connected.

[0025] The rod may for example be embedded in the first end of the lug, which induces its rotation around the respective axis of rotation when the second end of the lug rotates around the axis of the rod during rotation of the rotary member.

[0026] According to one aspect, the second end of said tab comprises a portion engaged in a housing of the rotary member. The housing and said portion are in particular shaped so as to allow rotation of the leg around the axis of the rod, as well as rotation of the rotating member around the central axis.

[0027] Advantageously, each housing and each leg are shaped to ensure that all the blades of the at least one swirler move at the same time and at the same angle around their respective axes of rotation.

[0028] According to one aspect, said portion of the second end of the tab has a substantially rectangular shape engaged in the housing of the rotary member, said housing being of a shape substantially complementary to said portion of the tab, with peripheral clearance between said portion of the tab and said housing.

[0029] Thanks to the peripheral clearance provided between the housing and the portion of the second end of the tab engaged in this housing, the rotary member can rotate around the central axis.

[0030] According to another example, the portion of the second end of the tab engaged in the housing could have a substantially flared shape converging in the direction from the rod to the rotary member. The housing would also in this case have a shape complementary to that of said portion of the tab, with a peripheral clearance being formed between the two.

[0031] According to one aspect, the rotary member comprises an alternation of solid parts and hollow parts, each hollow part forming one of the housings for receiving said portion of the second end of each leg.

[0032] Each housing being formed by one of the hollow parts, and the hollow parts being arranged alternately with the solid parts, when the rotary member rotates around the central axis, a lateral edge of each solid part comes into abutment with the portion of each lug engaged in the housings. Thus, each lug rotates integrally with the rotary member, and causes the rotation of the associated rod and blade around their axis of rotation.

[0033] This alternation of solid and hollow parts also allows that, whatever the direction of rotation of the rotary member, one of the solid parts, in particular one of its lateral edges, comes into contact with the portion of each lug engaged in the housings. The movements of the blades from the first position to the second position, and vice versa, are thus possible, which makes it possible to modify the timing of the at least one swirler, whether by increasing it or reducing it. The timing of the at least one swirler can thus be adjusted according to the operating speed of the turbomachine.

[0034] Each hollow part preferably comprises two side walls substantially facing each other in a circumferential direction, and a bottom wall connecting the two side walls. Each side wall of the hollow parts is advantageously formed by a lateral edge of one of the solid parts. In the In this text, "circumferential direction" means a direction which extends around the central axis.

[0035] According to one example, the bottom wall may form a substantially right angle with each of the side walls of the respective hollow portion. In order to ensure that the tab can rotate at the same time as the rotating member, the corners of the tab which radially face the bottom wall of the respective housing may be substantially rounded.

[0036] According to one aspect, each tab extends in a plane substantially perpendicular to the rod. The tab can thus be used to more easily control the rotation of the respective rod about the corresponding axis of rotation, and therefore, the rotation of the associated blade.

[0037] According to a non-limiting example, the tab may be made in one piece with the rod. Alternatively, the tab may be a part attached to the rod.

[0038] According to one aspect, the assembly further comprises means for returning the plurality of blades to the first position.

[0039] By means of this return means, the blades can spontaneously return to the first position after the force which moved them relative to this first position ceases.

[0040] According to one example, the return means may be a spring comprising a first end portion attached to the at least one injection system, and a second end portion attached to the rotary member.

[0041] When the aerodynamic force exerted on the extrados of the blades of the at least one swirler increases, the blades are moved to the second position. Also, an increase in the aerodynamic force exerted on the extrados of the blades decreases the setting of the swirler, which also causes an increase in the permeability of the injection system of the assembly. The return means has the action of returning the blades to the first position, thus increasing the setting of the swirler and therefore, decreasing the permeability of the injection system of the assembly.

[0042] In this example, the movement from the first position to the second position is therefore induced by the aerodynamic force of the air flow passing through the swirler, while the movement from the second position to the first position is induced by the release of the elastic potential energy stored in the return means. The movement between the first and second positions is thus passively controlled.

[0043] According to one aspect, the assembly further comprises means for controlling the movement of the plurality of blades between the first position and the second position.

[0044] According to one example, the control means may be a motor capable of controlling the movement of the blades from the first position to the second position, or vice versa. This motor can be operated manually by a user, or based on signals received from one or more sensors, among others.

[0045] Alternatively, the control means comprises first connecting means cooperating with second form connecting means, the first and second form connecting means being configured to drive the rotary member in rotation about said central axis. The first form connecting means comprise for example a plate carried by an injector capable of moving along the central axis of the injection system, this plate comprising a slot substantially oblique with respect to the central axis. The second form connecting means may be a pin carried by the rotary member. This pin is advantageously shaped and positioned to be engaged in the slot of the first connecting means when the injector moves along the central axis. The slot being oblique, when the injector moves along the central axis, the rotary member rotates about this central axis thanks to the cooperation between the slot and the pin.The auger blades are thus moved between the first position and the second position depending on the direction of movement of the injector.

[0046] The movement between the first and second positions can therefore also be actively controlled. Actively controlling such a movement allows for more precise control of the spin timing.

[0047] It is possible to provide in the same assembly both means for passively controlling and means for actively controlling the movement between the first and second positions.

[0048] According to one aspect, the rotary member is arranged axially between the at least one twister and an axial retention ring of the rotary member arranged on an upstream face of the at least one twister, the retention ring being held in axial position by holding fingers secured to said at least one twister.

[0049] The holding fingers make it possible in particular to hold the rotary member and the retention ring axially in position, while allowing the rotary member to move in rotation. According to one example, the holding fingers also make it possible to hold the rotary member and the retention ring radially. This prevents the rotary member and the retention ring from becoming detached from the assembly.

[0050] According to one aspect, the axis of rotation (O) of each blade (62, 62-1, 62-2) is substantially parallel to the central axis (C). In other words, the axes of rotation of all the blades are included in the same wall of revolution. This arrangement of the axes of rotation makes it possible to reduce the size of the turbomachine in the axial direction.

[0051] According to one aspect, the axis of rotation of each blade is substantially perpendicular to the central axis. This arrangement of the axes of rotation makes it possible to reduce the size of the turbomachine in the radial direction.

[0052] According to one aspect, the setting of the at least one twist is between 5° and 90°, preferably between 10° and 90°.

[0053] As indicated above, each blade can advantageously be positioned in any position between the first position and the second position depending on the angle of rotation of the rotary member. Thus, each blade can be moved around its respective axis of rotation by an angle having any value within the aforementioned ranges. The setting of the spinner can thus be finely adjusted.

[0054] According to another aspect, there is described an assembly as described above, in which the injection system comprises a first swirler and a second annular swirler with a central axis, the first swirler comprising an annular row of first blades mounted to be movable in rotation about a respective axis of rotation between the first position and the second position, an air passage section in said first annular swirler being smaller in the first position than in the second position of the first blades, the second swirler comprising an annular row of second blades mounted to be movable in rotation about a respective axis of rotation between the first position and the second position, an air passage section in said second annular swirler being smaller in the first position than in the second position of the second blades,wherein the rotary member is rotatably coupled to said annular rows of first blades and second blades so as to simultaneously rotate the first blades and the second blades between the first position and the second position upon rotation of said rotary member.

[0055] The first swirler corresponds for example to an internal swirler and the second swirler corresponds for example to an external swirler of the injection system, the external swirler being arranged downstream of the internal swirler in a direction of air circulation in the swirler. It is also possible to provide three coaxial swirlers in the injection system.

[0056] According to one aspect, the number of first blades is greater than the number of second blades. According to one example, the number of first blades is at least twice the number of second blades.

[0057] According to one aspect, the assembly further comprises a plurality of first rods, wherein each first rod is integral with one of the first blades or one of the second blades.

[0058] According to one aspect, the assembly further comprises a plurality of second rods, wherein each second rod is integral with one of the first blades and one of the second blades. Each second rod thus makes it possible to move the first blades and the second blades between the first position and the second position, which reduces the overall size of the assembly.

[0059] According to another aspect, a turbomachine, such as a turbojet or a turboprop, is described, comprising at least one assembly as described above. Brief description of the drawings

[0060] Other characteristics, details and advantages will appear on reading the detailed description below, and on analyzing the attached drawings, in which: Fig.l

[0061] [Fig.l] shows a schematic axial sectional view of a part of a turbomachine according to an exemplary embodiment. Fig. 2

[0062] [Fig.2] shows a schematic perspective view from a first position of a turbomachine assembly according to a first exemplary embodiment. Fig. 3

[0063] [Fig.3] shows a schematic side view of the turbomachine assembly of [Fig.2], and a portion of a fuel injector head. Fig. 4

[0064] [Fig.4] shows a schematic view of the turbomachine assembly of the [Fig.2] showing, to the left of line II, a frontal section of an internal tendril of the set and, to the right of this line II, on the gray area, a frontal section of an external tendril of the set. Fig. 5

[0065] [Fig.5] shows a schematic upstream front view of an injection system included in the assembly of [Fig.2], in which, to the left of line II-II, the blades of this injection system are in a first position, and, to the right of line II-II, the blades are in a second position. Fig. 6

[0066] [Fig.6] shows a schematic upstream front view of the assembly of [Fig.2] according to an alternative embodiment. Fig. 7

[0067] [Fig.7] shows a schematic perspective view from a second position of the whole of [Fig.2]. Fig. 8

[0068] [Fig.8] shows a schematic perspective view of the assembly of [Fig.2] according to the embodiment variant of [Fig.6], and of a part of a fuel injector. Fig. 9

[0069] [Fig.9] shows a schematic perspective view of a rod included in the whole [Fig.2]. Fig. 10

[0070] [Fig. 10] shows a schematic sectional view of part of a turbomachine assembly according to a second embodiment comprising an axial air swirler. Description of the embodiments

[0071] To facilitate understanding of the invention, an axial direction A is defined which extends along a central axis C of an injection system 10, or parallel to this central axis A, and a radial direction R which is perpendicular to the axial direction A. Also, in the present text, “axial” means any direction substantially parallel to the central axis C, and “radial” extends from any direction substantially perpendicular to the central axis C.

[0072] [Fig.l] shows an axial sectional view of a part of a turbomachine 100. The turbomachine is for example a turbojet or a turboprop.

[0073] As visible in this figure, the turbomachine comprises an annular combustion chamber 14 having an axis of revolution V.

[0074] In the remainder of the description, when the terms “internal” and “external” are used to describe the combustion chamber 14, these terms are defined with reference to the axis of revolution V of the combustion chamber 14. When the terms “internal” and “external” are used to describe the injection system 10, these terms are defined with reference to the central axis C of the injection system 10.

[0075] The combustion chamber 14 is housed inside a casing 16. The combustion chamber 14 is in particular arranged at the outlet of a centrifugal diffuser 18 mounted at the outlet of a high-pressure compressor (not shown). The combustion chamber 14 is followed by a high-pressure turbine 20 of which only the inlet distributor 22 is shown.

[0076] As can be seen from [Fig.l], a space 24, called the external bypass space, exists between a radially external wall 26 of the chamber 14 and the casing 16. The external bypass space 24 receives bypass air from the combustion chamber 14. This bypass air corresponds to a flow of air from the high-pressure compressor which flows outside the combustion chamber 14.

[0077] The combustion chamber 14 comprises a radially inner wall 28 and the radially outer wall 26 presented above. The radially outer wall 26 and the radially inner wall 28 are walls of revolution, for example frustoconical with a section reducing downstream. Any other shape of combustion chamber 10 is also possible. For example, chamber 10 could alternatively be a double-headed combustion chamber.

[0078] It is noted that in the present text, the terms “upstream” and “downstream” are to be interpreted with reference to a conventional direction of flow of the air flow sucked in by the turbomachine 100 in service.

[0079] The radially outer wall 26 and the radially inner wall 28 are preferably coaxial and arranged one inside the other. Such a combustion chamber is said to be convergent. The radially inner 28 and outer 26 walls are connected at their upstream ends to an annular chamber bottom wall 30 and fixed downstream for example by inner 32 and outer 34 annular flanges.

[0080] As illustrated in [Fig.l], the external annular flange 34 may bear radially externally on the casing 16. Furthermore, the external annular flange 34 may bear axially on a radial flange 38 for fixing the distributor 22 of the high-pressure turbine to the casing 16.

[0081] The internal annular flange 32 of the combustion chamber 14 is for example in radial and axial support on an internal annular part 40 for fixing the distributor 22 to an internal annular wall 4L

[0082] The external wall 26 and the casing 16 each comprise at least one orifice for installing at least one spark plug 42 for the combustion chamber 14.

[0083] The external annular wall 26 of the combustion chamber 14 may also comprise an annular row of primary orifices 44 for diluting an air / fuel mixture arranged upstream of the spark plug 42.

[0084] The chamber bottom 30 comprises openings 45, preferably regularly distributed around the axis of revolution V. Each opening 45 constitutes an inlet to the combustion chamber 14.

[0085] Each opening 45 is shaped to receive an injector 46, at least partially, and a respective injection system 48. The injection system 48 installed in each opening 45 is mounted around a respective central axis C.

[0086] Each injector 46 comprises an injector head 47 and a mat 49. The mat 49 may extend from the injector head 47 to the casing 16, for example substantially perpendicular to the central axis C.

[0087] The injector head 47 is shaped to be received in the respective opening 45, in particular inside a cavity 50 delimited radially by the injection system 48 installed in this opening 45. The injector head 47 advantageously extends around the central axis C of the injection system 48 installed in the respective opening 45.

[0088] Each injector 46 makes it possible to introduce fuel into the combustion chamber 14. The injection system 48 is, as will be detailed, configured to introduce air into the chamber 10.

[0089] The fuel injected into the chamber 10 is mixed with the air introduced into the chamber 10 by the injection system 48, which makes it possible to produce a mist of drops of air-fuel mixture which is ignited by the spark plug 42 during the ignition or re-ignition phases of the turbomachine. The flame created is maintained during the other operating phases of the turbomachine, during which the spark plug 42 is extinguished, by the continuous supply of air-fuel mixture.

[0090] Now an example of an injection system 48 will be described that can be mounted at the inlet of the combustion chamber 14, in particular in one of the cavities 45. The description given below for this injection system 48 is applicable to the injection systems 48 received in each of the other cavities 45.

[0091] As indicated previously, the injection system 48 is arranged around the central axis C of the opening 45.

[0092] As seen in Figures 2 and 3, the injection system 48 comprises at least one annular auger 54 described later. The system 48 may also comprise a mixing bowl 55.

[0093] The mixing bowl 55 comprises a substantially frustoconical wall 56 with a central axis C. The wall 56 is flared downstream and connected at its downstream end to a cylindrical rim 58 extending upstream and mounted axially in the opening 45 of the chamber bottom wall 22. The cavity 50 in which the head 47 of the injector 46 is received is for example delimited radially by the cylindrical rim 58.

[0094] The frustoconical wall 56 of the bowl comprises at least one annular row of air injection orifices 60 regularly distributed around the axis C of the injection system 48. The centers of the air injection orifices 60 are for example spaced from each other by the same distance. According to one example, the air injection orifices 60 all have the same shape and the same surface area. The air injection orifices 60 are for example circular.

[0095] The orifices 60 make it possible to introduce a flow of air from the high-pressure compressor inside the bowl 55, and therefore, inside the chamber 14.

[0096] As indicated, each injection system 48 comprises at least one annular swirler 54. The at least one swirler 54 preferably has a central axis C, and may be an axial swirler or a radial swirler.

[0097] As will be detailed, each swirler 54 comprises an annular row of blades 62, preferably regularly distributed around the central axis C. A space is formed between two consecutive blades 62 of the swirler 54, all of the spaces formed between all the blades 62 of the same swirler 54 defining an air passage section in the swirler 54. An air flow from the high-pressure compressor can thus pass through the swirler 54 through the air passage section, this flow then being introduced into the combustion chamber 14, for example via the bowl 55. The air flow from each swirler 54 is for example a rotating air flow.

[0098] In a first embodiment illustrated in Figures 1 to 8, the injection system comprises a first swirler 54-1, called the internal swirler, and a second swirler 54-2, called the external swirler. The internal swirler 54-1 and external swirler 54-2 are preferably coaxial with axis C. In this example, the internal swirler 54-1 is placed upstream of the external swirler 54-2 in the axial direction A.

[0099] As can be seen in particular in Figures 2 and 3, the internal swirler 54-1 comprises an annular row of blades 62-1, referred to below as “first blades”. The first blades 62-1 are preferably distributed regularly around the axis C.

[0100] The external swirler 54-2 comprises another annular row of blades 62-2, called in the following “second blades” and visible in figures 3 and 4. The second blades 62-1 are preferably regularly distributed around the axis C.

[0101] Each of the first blades 62-1 and the second blades 62-2 comprises a radially external face 64, called the extrados, and a radially internal face 66, called the intrados.

[0102] As is clear from [Fig.4], illustrating, to the left of line II, the distribution of the blades 62-1 on one half of the internal swirler 54-1 and, to the right of this line Ü-II, on the gray area, the distribution of the blades 62-2 on one half of the external swirler 54-2, the number of first blades 62-1 may be greater than the number of second blades 62-2. According to a non-limiting example, the number of first blades 62-1 is at least twice the number of second blades 62-2.

[0103] Advantageously, the number of first blades 62-1 is an even integer multiple of the number of second blades 62-2. This, associated with the regular distribution of the blades 62-1, 62-2 around the axis C, makes it possible to obtain a distribution of the blades 62-1, 62-2 symmetrical with respect to a plane of symmetry comprising the axial and radial directions.

[0104] Of course, the number of first blades 62-1 could be equal to the number of second blades 62-2. According to another variant, the number of first blades 62-1 could be less than the number of second blades 62-2.

[0105] The first blades 62-1 and the second blades 62-2 are mounted to be movable in rotation about a respective axis of rotation O between a first position and a second position. Preferably, the axis of rotation O of each second blade 62-2 is coincident with the axis of rotation O of one of the first blades 62-1. This makes it possible to control with the same mechanism the rotation of the first blade 62-1 and the second blade 62-2 sharing the same axis of rotation O, as will be detailed.

[0106] In the example of Figures 1 to 8, the axis of rotation O of each blade 62-1, 62-2 is substantially parallel to the central axis C, without this being limiting. In other words, the axes of rotation O of all the blades 62-1, 62-2 are included in the same wall of revolution.

[0107] [Fig.5] shows, to the left of line II-II, the first position of the first blades 62-1, and, to the right of line II-II, the second position of the first blades 62-1.

[0108] Depending on the position of each blade 62, the air passage section in each swirler 54 changes. In this case, in the first position of the first blades 62-1, an air passage section in the inner swirler 54-1 is smaller than in the second position of the blades 62-1. Similarly, in the first position of the second blades 62-2, an air passage section in the outer swirler 54-2 is smaller than in the second position of the blades 62-2. Also, as will be detailed, in the second position of the blades 62, the air permeability of each swirler 54 is greater than this permeability in their first position.

[0109] It is noted that the air passage section of the first swirler 54-1 when the first blades 62-1 are in the first position may be, in size and shape, equal to or different from the air passage section of the second swirler 54-2 when the second blades 62-2 are in the first position. Similarly, the air passage section of the first swirler 54-1 when the first blades 62-1 are in the second position may be, in size and shape, equal to or different from the air passage section of the second swirler 54-2 when the second blades 62-2 are in the second position.

[0110] Furthermore, when each blade 62 is moved in rotation about the respective axis of rotation O, an angle a formed between a radial direction L passing through a radially outer edge of the blade 62 and a direction T tangent to the intrados 66 of this blade 62 is modified. The angle a, shown in [Fig.5], is commonly known as “setting”. The rotation of each blade 62 about its axis of rotation O therefore makes it possible to modify the setting a of the respective swirler 54.

[0111] Advantageously, the pitch a of each swirler 54 decreases when its blades 62 move from the first position to the second position. On the contrary, the pitch a increases when the blades 62 move from the second position to the first position. This is clearly illustrated in [Fig.5]. Indeed, as indicated previously, [Fig.5] shows, to the left of the line II-II, the first position of the first blades 62-1, and, to the right of the line II-II, the second position of the first blades 62-1. It is clear from this figure that the pitch a', corresponding to the pitch a when the blades 62-1 are in the first position, is greater than the pitch a”, corresponding to the pitch a when the blades 62-1 are in the second position.

[0112] According to a non-limiting example, the setting a of each spinner 54 is between 5° and 90°, preferably between 10° and 90°. The upper limit of these ranges of values ​​corresponds to the setting of the corresponding spinner 54 when its blades 62 are in the first position, while the lower limit of these ranges of values ​​corresponds to the setting of the corresponding spinner 54 when its blades 62 are in the second position.

[0113] It is noted that when several spinners 54 are present in the injection system 48, in this case the first spinner 54-1 and the second spinner 54-2, the value of the timing a of each spinner 54 in its first position may be different from the value of the timing a of the other spinners 54 in their first position. Similarly, the value of the timing a of each spinner 54 in its second position may be different from the value of the timing a of the other spinners 54 in their second position.

[0114] Advantageously, each blade 62 can remain in any position between the first position and the second position. Also, the setting a of each spinner 54 can take at a given instant any value between the aforementioned ranges of values. The setting a of each spinner 54 can therefore be finely adjusted.

[0115] The injection system 48 is part of a turbomachine assembly which further comprises a rotary member 68 with a central axis C. This turbomachine assembly can be installed at the inlet of the combustion chamber 14, in particular in one of the openings 45.

[0116] A first example of an assembly for a turbomachine is illustrated in FIGS. 2 to 8. This example of an assembly is formed by the injection system 48 provided with the two internal 54-1 and external 54-2 swirlers as described previously, and a first non-limiting example of a rotary member 68 which is described below.

[0117] As can be seen in particular in Figures 6 and 7, the rotary member 68 has a general ring shape with a central axis C. The rotary member 68 thus comprises a radially internal edge 70 and a radially external edge 72.

[0118] The rotary member 68 comprises an alternation of solid parts 74 and hollow parts 76. Preferably, the solid parts 74 and hollow parts 76 are distributed regularly around the central axis C.

[0119] Each hollow portion 76 comprises a first side wall 78, a second side wall 80, and a bottom wall 82. The side walls 78, 80 are advantageously opposite each other in the circumferential direction.

[0120] As can be seen from Figures 4 and 6, the side walls 78, 80 extend from the radially inner edge 70 of the rotary member 68 towards the radially outer edge 72, without reaching it. The bottom wall 82 connects the side walls 78, 80, preferably at their ends closest to the radially outer edge 72. Also, each hollow portion 76 of the rotary member 68 forms a housing 77.

[0121] In the figures, the first side wall 78 and the second side wall 80 of each housing 77 are substantially parallel to each other and form a substantially right angle with the bottom wall 82 which connects them. The housing 77 thus has a substantially square or rectangular shape. Other arrangements of the side walls 78, 80 are however possible. For example, the first side wall 78 and the second side wall 80 of each housing 77 could be convergent towards each other in the direction of the radially external edge 72 of the rotary member 68. Also, the housing 77 would have a flared shape.

[0122] Each solid part 74 is delimited by the first side wall 78 of a first housing 77, and by the second side wall 80 of a second housing 77, the first housing 77 and the second housing 77 corresponding to the hollow parts 76 arranged on either side of the corresponding solid part 74. Each solid part 74 is further delimited by the radially internal edge 70 of the rotary member 68. The radially internal edge 70 connects the side walls 78, 80 which delimit the solid part 74.

[0123] The rotary member 68 is mounted for example upstream of the internal spiral 54-1. In particular, the rotary member 68 may come into contact with an upstream face of the internal spiral 54-1. In order to maintain the rotary member 68 in this position, the assembly may comprise an axial retention ring 83. The ring 83 is for example a circlip.

[0124] The rotary member 68 is advantageously arranged axially between the internal spiral 54-1 and the retention ring 83.

[0125] In the non-limiting example of the figures, the retention ring 83 is held in axial position by holding fingers 85 secured to the injection system 48. In this case, the holding fingers 85 project substantially axially from the internal spiral 54-1, without this being limiting. As is clear in particular from [Fig. 7], each holding finger 85 may have an L-shape, with a substantially axial portion 85-1 connected directly to the injection system 48, and a substantially radial portion 85-2 which extends from the end of the portion 85-1 opposite the injection system 48. This L-shape allows each holding finger 85 to hold the rotary member 68 and the retention ring 83 in position both axially and radially. Of course, other shapes and numbers of holding fingers 85 are conceivable.

[0126] The rotary member 68 is configured to rotate about the central axis C. In some cases, the rotary member 68 includes a hook or tab 84 (visible in Figures 2, 4, 7) and / or a pin 86 (visible in Figures 6 and 8) which are used to drive the rotary member 68 in rotation about the central axis C, as will be detailed. The hook 84 or pin 86 preferably projects substantially radially outwardly from, for example, the radially outer edge 72 of the rotatable member 68.

[0127] Advantageously, the rotary member 68 is coupled in rotation to the annular row of blades 62 of each swirler 54 of the injection system. The blades 62 of each swirler 54 are thus configured to move between the first position and the second position simultaneously with the rotation of the rotary member 68.

[0128] According to the non-limiting example of the figures, the rotational coupling between the rotary member 68 and each blade 62 can be done by a respective rod 88.

[0129] Now an example of rod 88 will be described with reference to [Fig.9], all the rods of the set being similar or identical to this one.

[0130] The rod 88 has for example a substantially cylindrical shape extending along a longitudinal axis Q.

[0131] The rod 88 comprises a first end 88-1 and a second end 88-2. The first end 88-1 is connected to a link mechanism 90 which will be described in the following.

[0132] The second end 88-2 and the entire length of the rod 88 which is comprised between the first end 88-1 and the second end 88-2 may carry one or more blades 62, as visible in [Fig.8]. For this purpose, each blade 62 comprises a hole extending advantageously along its axis of rotation O. Also, when the rod 88 is installed in the assembly, its longitudinal axis Q is coincident with the axis of rotation O of any blade 62 which it carries. Preferably, the rod 88 is received tightly in the hole of the blade 62 to which it is connected. The rod 88 and the corresponding blade 62 are thus arranged to move in rotation integrally.

[0133] It is noted that, when the injection system 48 comprises several swirlers 54, the rods 88 can be divided into first rods 89 and second rods 91 depending on the number of blades they carry. In FIGS. 2 to 8, the injection system 48 comprises the internal swirler 54-1 and the external swirler 54-2, the external swirler 54-2 comprising a smaller number of second blades 62-2 than first blades 62-1 of the internal swirler 54-1. The first rods 89 then correspond to the rods 88 which are connected only to one of the first blades 62-1, while the second rods 91 correspond to the rods which are connected to one of the first blades 62-1 and to one of the second blades 62-2. A single second rod 91 thus makes it possible to simultaneously move in rotation the first blade 62-1 and the second blade 62-2 which it carries, which makes it possible to reduce the overall size of the assembly.

[0134] The connecting rod mechanism 90 comprises a tab 92. The tab 92 extends for example in a plane substantially perpendicular to the rod 88.

[0135] The leg 92 includes a first end 92-1 which is integral with the first end 88-1 of the rod 88. In some cases, the leg 92 may be made of a single holding with the rod 88. In other cases, the tab 92 may be an attachment to the rod 88. In such a case, the rod 88 may be embedded in the first end of the tab 92. Advantageously, the rod 88 and the tab 92 are connected so as to ensure that the tab 92 and the rod 88 move integrally in rotation about the axis Q of the rod 88.

[0136] The tab 92 also comprises a second end 92-2 opposite said first end 92-1. The second end 92-2 of the tab 92 comprises a portion 94 engaged in one of the housings 77 of the rotary member 68. The tab 92 therefore makes it possible to individually connect each rod 88 to the rotary member 68, the tab 92 connected to each rod 88 being engaged in a respective housing 77 of the rotary member 68.

[0137] As is clear in particular from [Fig. 6], the portion 94 of the tab 92 advantageously has a shape complementary to that of the housing 77 in which it is received. For example, when the housing 77 has a substantially rectangular shape, the portion 94 also has a substantially rectangular shape.

[0138] The housing 77 and the portion 94 are in particular shaped so as to allow rotation of the tab 92 around the axis Q of the rod 88, as well as rotation of the rotary member 68 around the central axis C. For this purpose, the dimensions of the portion 94 and of the housing 77 where it is engaged are chosen so as to guarantee that a peripheral clearance 95 exists between the portion 94 and the housing 77. Indeed, as explained previously, each housing 77 is formed by one of the hollow parts 76 of the rotary member 68, and the hollow parts 76 are arranged alternately with the solid parts 74. Also, when the rotary member 68 rotates around the central axis C, a lateral edge 78, 80 of each housing 77 comes into abutment with the portion 94 which it receives. Each leg 92 thus rotates integrally with the rotary member 68, and causes rotation around the corresponding axis of rotation O of the rod 88 and the blade 62 with which it is associated.Thanks to the peripheral clearance 95, the lug 92 is prevented from getting stuck in the housing 77, which would prevent the rotational movement of the lug 92, the rotary member 68, the rod 88 and each blade 62.

[0139] It should be noted, however, that the peripheral clearance 95 must be as small as possible while ensuring that the lug 92 can rotate, simultaneously with the rotation of the rotary member 68, around the axis Q of the rod 88 to which it is connected. Indeed, as indicated previously, the rod 88 is driven in rotation by the lug 92 during the rotation of the rotary member 68, which causes the displacement of any blade 62 carried by the rod 88 between the first and second positions. In order for each blade 62 to move between the first and second positions simultaneously with the rotation of the rotary member 68 around the axis C, the clearance 95 must be as small as possible. On the contrary, there would be a gap between the start of the rotation of the rotary member 68 and the start of the displacement of the blades 62.

[0140] In certain cases, the corners of the tab 92 which are radially opposite the bottom wall 82 of the respective housing 77 may be substantially rounded. This makes it possible to obtain a greater clearance 95 but without having to increase the dimensions of the rotary member 68, which would increase the size, nor having to reduce the size of the portion 94, which would create a significant offset between the start of the rotation of the rotary member 68 and the rotation of each blade 62.

[0141] As indicated previously, the rotation of the rod 88 around its axis Q causes the displacement of the blade 62 which it carries between the first position and the second position. Advantageously, each housing 77 and each lug 92 are shaped to ensure that all the rods 88, and therefore that all the blades 62 of each spiral 54, move at the same time and at the same angle around the respective axis of rotation O.

[0142] It is noted that thanks to the alternation of solid parts 74 and hollow parts 76 of the rotary member 68, each blade 62 can be moved from the first position to the second position, or vice versa. Indeed, this alternation allows that, whatever the direction of rotation of the rotary member 68, one of the solid parts 74, in particular one of its lateral edges 78, 80, comes into contact with the portion of each tab 92 engaged in the housings 77. The movements of the blades 62 from the first position to the second position, and vice versa, are thus possible.

[0143] Also, thanks to the rod 88 and the connecting rod mechanism 90, the rotary member 68 is coupled in rotation to the annular row of blades 62 of each swirler 54 of the injection system. It should of course be noted that the configuration presented above is not limiting, and that other ways of coupling in rotation the rotary member 68 and the blades 62 of each swirler 54 are conceivable.

[0144] As explained above, when the blades 62 are moved between the first position and the second position, the air permeability and the setting of the respective swirler 54 vary. The rotation of the rotary member 68 around the central axis thus makes it possible to adjust the air permeability and the setting of the swirler 54, in particular as a function of the operating speed of the turbomachine.

[0145] For example, in the ignition or re-ignition phase, it is advantageous to reduce the permeability of the injection system 48 in order to enrich the combustion chamber 14 with fuel. Indeed, when the permeability of the injection system 48 decreases, the fuel enrichment rate in the combustion chamber 14, defined as the ratio between a flow rate of fuel injected into the chamber 14 and a flow rate of air injected into the chamber 14, increases. This allows the flame kernel initiated in front of the spark plug to more easily reach the fuel recirculation zone of the injection system, and the flame generated in the chamber to propagate without difficulty to the neighboring injection systems. The chances of successfully igniting the combustion chamber 14 during the ignition or re-ignition phases of the turbomachine 100 are thus increased. The re-ignition ceiling of the turbomachine 100 is also increased when the permeability of the injection system 48 decreases. Also, during ignition or re-ignition phases, it is advantageous for the blades 62 to move from the second position to the first position.

[0146] On the contrary, when the turbomachine 100 is operating at full throttle, for example during the takeoff phase, it is advantageous to increase the permeability of the injection system 48 to deplete the combustion chamber 14 of fuel, in particular the primary zone thereof, in order to reduce pollutant emissions. In full throttle regimes it is therefore advantageous for the blades 62 to move from the first position to the second position.

[0147] The performance of the turbomachine 100 can therefore be improved as a function of the regime in which it operates from the displacement of the blades 62 between the first position and the second position described above, or, in other words, from the modification of the timing of the swirler(s) 54 of the injection system 48. As described above, the performance of the turbomachine 100 can be improved in particular in terms of fuel consumption (with in particular a reduction in consumption) or re-ignition ceiling (with an increase in the latter, which makes it possible to guarantee the re-ignition of the combustion chamber at higher heights). The emission of pollutants when the turbomachine 100 is in service can also be reduced thanks to the assembly described here.Other performances of the turbomachine 100 that can be improved thanks to this assembly concern the stability of the combustion chamber of the turbomachine, or the limit of blowing of the flame in the combustion chamber.

[0148] Furthermore, as also indicated above, thanks to the possibility of placing each blade in any position between the first position and the second position, the assembly described can be used as test equipment to experimentally determine what the optimal setting of each spinner is as a function of the operation of the turbomachine.

[0149] To move the blades 62 between the first position and the second position, several mechanisms are possible.

[0150] A first example of a mechanism is illustrated in Figures 2 to 4 and 7. In this case, the assembly is provided with a return means 96 for returning the plurality of blades 62 to the first position. The return means 96 is for example a compression or traction spring 97 which is attached, at a first end portion, to the hook 84 of the rotary member 68, and at a second end portion opposite the first end portion, to a hook 98 provided on the injection system 48. for example, the hook 98 projects substantially radially from a twist 54, in this case the twist 54-1.

[0151] The spring 97 is arranged so that its elastic potential energy is zero when the rotary member 68 is in a position which leaves the blades 62 in their first position. On the contrary, the spring 97 is arranged so that the absolute value of its elastic potential energy increases when the blades 62 are moved to the second position concomitantly with the rotation of the rotary member 68. The spring 97 thus spontaneously returns to its state of zero elastic potential energy as soon as the force which caused the displacement of the blades 62 to the second position ceases.

[0152] In this mechanism, the passage of the blades 62 between the first position and the second position can be done passively. In particular, the passage from the first position to the second position can be induced by an aerodynamic force exerted by the air flow passing through each swirler 54 on the blades 62, in particular on the extrados 64 thereof. When the aerodynamic force exerted on the extrados of the blades 62 of each swirler 54 increases, in particular by an increase in the air flow entering the swirler 54, the blades 62 are moved to the second position. Also, an increase in the aerodynamic force exerted on the extrados 64 of the blades 62 decreases the setting of the swirler 54, which also causes an increase in the permeability of the injection system 48 of the assembly.The blades 62 being coupled in rotation to the rotary member 68, this movement of the blades 62 induced by the aerodynamic force is accompanied by a movement of the rotary member 68 around the central axis C in a direction causing a compression of the spring 97 (if it is a compression spring) or a stretching of the spring 97 (if it is a tension spring). Consequently, the elastic potential energy stored by this spring 97 becomes non-zero. Once the aerodynamic force ceases, the transition from the second position to the first position also occurs passively. In particular, the spring 97 spontaneously releases the stored elastic potential energy, which causes the movement of the rotary member 68 to the position where the blades 62 return to their first position.If the aerodynamic force on the extrados 64 of the blades decreases continuously, the spring 97 releases part of the stored elastic potential energy, so that the rotary member 68 is moved to a position which brings the blades 62 closer to the first position without reaching it.

[0153] This first mechanism could, according to a variant, be coupled to a means 102 for controlling the movement of the plurality of blades 62 from the first position to the second position.

[0154] For example, the control means could be an electric motor (not shown). In such a case, the passage of the blades 62 from the first position to the second position can be done actively from an actuation of the motor which controls the movement of the rotary member to a position where the blades 62 are in their second position.

[0155] The motor can in particular be actuated by an external command, for example a manual command from a user from a human-machine interface.

[0156] Alternatively, the external command may be a signal received by the engine from one or more sensors installed in the aircraft. According to a non-limiting example, each sensor may send as a signal a fuel pressure in the fuel circuit of the turbomachine, or a bypass air pressure outside the combustion chamber 14. Indeed, depending on the operating speed of the turbomachine 100, these fuel or bypass air pressures may be different, with in particular lower values ​​during the ignition, re-ignition or ground idle phases, and higher values ​​beyond ground idle. As explained previously, the transition from the first position to the second position of the blades 62 is particularly advantageous when the turbomachine 100 is operating at full throttle.Therefore, preferably, the engine sends a command allowing the blades 62 to move from the first position to the second position when it receives a signal from the sensors which corresponds to the eigenvalues ​​of the parameters indicated above when the turbomachine 100 operates beyond ground idle.

[0157] Once the action of the motor ceases, the blades 62 return spontaneously, that is to say, passively, to the first position thanks to the release of the elastic potential energy stored by the spring 97 when the motor control stops.

[0158] According to a second example of a mechanism not illustrated, the transition from the first position to the second position, and vice versa, of the blades, can be controlled by an electric motor similar or identical to that described above. In such a case, the assembly can be devoid of the spring 97.

[0159] A third example of a mechanism for moving the blades 62 between the first position and the second position is illustrated in [Fig.8].

[0160] In this case, the rotation of the rotary member 68 can be controlled by an axial displacement of the injector head 47 between a first position further from the interior of the combustion chamber 14, called the retracted position, and a second position further into the combustion chamber 14, called the advanced position. The displacement of the injector head 47 between its retracted and advanced positions can be actively controlled, for example by a motor (not shown) which controls this displacement following an instruction from a user, or following a signal received from a sensor, such as the electric motor presented above. The displacement of the head injector head 47 between its retracted and advanced positions may also be passively controlled, for example from a piston (not shown) connected directly or indirectly to the injector head 47. The piston may move from passive controls, such as as a function of the fuel pressure in the fuel circuit of the turbomachine, or the bypass air pressure outside the chamber 14.

[0161] So that the movement of the injector head 47 between the retracted and advanced positions also causes the displacement of the blades 62 between the first position and the second position, the injector 36 may comprise at least one plate 110, visible in [Fig. 8]. The plate 110 is notably carried by the mast 49. The plate 110 may for example be welded to the mast 39. Advantageously, the plate 110 is arranged on the mast 39 in a radial position which prevents the plate 110 from being arranged axially opposite the injection system 48. Also, when the injector 36 is moved between the first position and the second position described above, the plate 110 does not collide with the injection system 48.

[0162] The plate 110 serves as a means 102 for controlling the movement of the blades 62. In particular, the plate 110 advantageously comprises a slot 112 which is oblique relative to the central axis C and in which the pin 86 of the injection system 48 is engaged.

[0163] According to a non-limiting example, the slot 112 comprises an open end, a closed end, a first internal face and a second internal face. The first internal face and the second internal face extend substantially opposite each other between the open end and the closed end.

[0164] Thanks to the oblique shape of the slot, the axial movement of the injector 46 drives the rotary member 68 in rotation around the central axis C. In particular, the relative movement of the slot 112 with respect to the pin 86 when the injector 36 moves between the first and second positions induces a force on the pin 86. This force causes the pin 86 to move along an oblique trajectory having the shape of the slot 112. Also, the rotary member 68 is driven in rotation around the central axis C, and therefore causes the displacement of the blades of each swirler 54. This makes it possible to increase or reduce the air passage section in each swirler 54 by the rotational coupling between the rotary member 68 and all of the blades 62.In particular, the oblique shape of the slot 112 allows, by the interaction between the pin 86 and the slot 112, to gradually rotate the rotary member 68 around the central axis C as the injector head 47 moves between the advanced position and the retracted position. The vanes 62 are consequently moved progressively from the first position to the second position and vice versa, being able to also adopt any position between these two extreme positions. It is therefore possible to finely adjust. the permeability of the injection system 48, which proves advantageous when the turbomachine operates at speeds involving intermediate powers between ground idle and full throttle speeds.

[0165] It is noted that in certain regimes of the turbomachine, the advanced position of the injector head 47 proves advantageous. For example, in the ignition or re-ignition phase, in addition to reducing the permeability of the injection system 48 in order to enrich the combustion chamber 14 with fuel, as mentioned above, it is advantageous to have the injector head 47 further recessed in the chamber 14 so that the fuel injected therein is more penetrating. On the contrary, when the turbomachine 100 is operating at full throttle, for example in the take-off phase, in addition to increasing the permeability of the injection system 48 to impoverish the combustion chamber 14 with fuel in order to reduce pollutant emissions, as already explained, it is advantageous to move the injector head 47 away from the interior of the chamber 14 in order to prevent the injector head 47 from being thermally damaged.Indeed, in the retracted position, the injector head benefits from a protective and cooling effect of the air which flows through the injection system 48. This limits coking and wear of the injector head 47 due to the high temperatures of the combustion chamber 14 in full throttle regimes.

[0166] Consequently, in order to obtain the best performance in each regime of the turbomachine, the mechanism of [Fig.8] is advantageously shaped so that, when the injector head 47 is in its retracted position, the vanes 62 are in the second position, and so that when the injector head 47 is in its advanced position, the vanes 62 are in the first position.

[0167] The present disclosure is not limited to the example described above. The present disclosure also encompasses all variants and combinations that may be envisaged by those skilled in the art within the framework of the protection sought. For example, as illustrated in [Fig. 10], the assembly could comprise a single swirler 54 comprising an annular row of blades 62 whose axis of rotation O is substantially perpendicular to the central axis C. In such a case, the rotary member 68 is mounted radially outside the injection system 48, preferably around the swirler 54. The housings 77 of the rotary member 68 are then formed by hollow parts which are interposed between solid parts, the hollow and solid parts being respectively similar to the hollow 76 and solid 74 parts of FIGS. 2 to 8 but extending substantially parallel to the central axis C.The remaining elements, characteristics and operating modes described above with reference to figures 1 to 9 are applicable to this turbomachine assembly of [Fig. 10]. Also, for the sake of brevity, they will not be detailed again.

[0168] According to another exemplary embodiment not illustrated, the injection system 48 comprises more than two swirlers 54, for example three coaxial swirlers.

[0169] It is also noted that when several spinners 54 are provided, a rotary member similar to the rotary member 68 could be associated with each spinner 54. In other words, the number of rotary members 68 could be equal to the number of spinners 54. This would make it possible to couple in rotation each rotary member 68 to the blades 62 of the respective spinner 54. The movement between the first and second positions of the blades 62 of one of the spinners 54 could thus be independent of the movement of the blades 62 of the other spinners 54 between their first and second positions.

[0170] In another exemplary embodiment not illustrated, the timing of the swirlers of all the injection systems provided at the inlet of the chamber 14 can be regulated simultaneously from the same mechanism. For this purpose, a diaphragm specific to each injection system can be provided, each diaphragm being configured to modify the timing of the swirler(s) of the respective injection system. In order to ensure that the timing of the swirlers of all the injection systems is modified at the same time and in the same manner, the set of diaphragms is connected to a cap common to all the injection systems and which is rotatably mounted, for example on the external wall 26 of the combustion chamber. This rotation of the cap causes the rotation of all the diaphragms.The rotation of the cap is for example controlled by a control device comprising a rotating shaft mounted by means of a sealing gland through the casing 16 of the chamber 14, the shaft carrying on its end inside the casing a fork which is engaged with a single radial ball joint carried by the cap. The rotation of the shaft can be controlled by any known means, whether mechanical (gear and rack system, connecting rod, etc.), hydraulic (cylinder and connecting rod) or electrohydraulic controlled by the regulating device of the turbomachine.

Claims

Claims

1. Assembly for a turbomachine comprising a central axis (C), in particular for an aircraft, the assembly comprising: - an injection system (48) for a combustion chamber (14) of the turbomachine (100), the injection system (48) extending around said central axis (C), the injection system comprising at least one annular swirler (54, 54-1, 54-2) with a central axis (C) comprising an annular row of blades (62, 62-1, 62-2) mounted to be movable in rotation around a respective axis of rotation (0) between a first position and a second position, an air passage section in said annular swirler (54, 54-1, 54-2) being smaller in the first position than in the second position of the blades;and - a rotary member (68) with a central axis (C) coupled in rotation to said annular row of blades (62, 62-1, 62-2) so as to simultaneously move in rotation the blades (62, 62-1, 62-2) of said annular row of blades (62, 62-1, 62-2) between the first position and the second position when said rotary member (68) is rotated, the assembly further comprising a means (96) for returning the plurality of blades (62, 62-1, 62-2) to the first position.;

2. An assembly according to claim 1, wherein each blade (62, 62-1, 62-2) of the annular row of blades is integral with a respective rod (88, 89, 91) individually connected to the rotary member (68) by a link mechanism (90).

3. Assembly according to the preceding claim, in which each connecting rod mechanism (90) comprises a lug (92) of which a first end (92-1) is integral with a first end (88-1) of the rod (88) and of which a second end (92-2) opposite said first end (92-2) is capable of being driven in rotation around a longitudinal axis (Q) of the rod (88) during rotation of the rotary member (68).

4. Assembly according to the preceding claim, in which the second end (92-2) of said tab (92) comprises a portion (94) engaged in a housing (77) of the rotary member (68).

5. Assembly according to the preceding claim, in which said portion (94) of the second end (92-2) of the tab (92) has a substantially rectangular shape engaged in the housing (77) of the rotary member (68), said housing (77) being of a shape substantially complementary to said portion of the tab (92), with a peripheral clearance (95) between said portion (94) of the tab (92) and said housing (77).

6. Assembly according to one of claims 4 or 5, in which the rotary member (68) comprises an alternation of solid parts (74) and hollow parts (76), each hollow part forming one of the housings (77) for receiving said portion (94) of the second end (92-2) of each leg (92).

7. Assembly according to one of claims 3 to 6, in which each leg (92) extends in a plane substantially perpendicular to the rod (88).

8. An assembly according to one of the preceding claims, further comprising means (102, 110) for controlling the movement of the plurality of blades between the first position and the second position.

9. Assembly according to one of the preceding claims, in which the rotary member (68) is arranged axially between the at least one spiral (54, 54-1, 54-2) and an axial retention ring (83) of the rotary member (68) arranged on an upstream face of the at least one spiral (54, 54-1, 54-2), the retention ring (83) being held in axial position by holding fingers (85) integral with said at least one spiral (54, 54-1, 54-2).

10. Assembly according to one of the preceding claims, in which the axis of rotation (0) of each blade (62, 62-1, 62-2) is substantially parallel to the central axis (C).

11. Assembly according to one of claims 1 to 9, in which the axis of rotation (0) of each blade (62, 62-1, 62-2) is substantially perpendicular to the central axis (C).

12. Assembly according to one of the preceding claims, in which the setting (a) of the at least one twist is between 5° and 90°, preferably between 10° and 90°.

13. Assembly according to one of the preceding claims, in which the injection system (48) comprises a first spiral (54-1) and a second spiral (54-2) annular with a central axis (C), the first spiral (54-1) comprising an annular row of first blades (62-1) mounted movable in rotation around a respective axis of rotation (O) between the first position and the second position, an air passage section in said first spiral annular (54-1) being smaller in the first position than in the second position of the first blades (62-1), the second swirler (54-2) comprising an annular row of second blades (62-2) mounted to be movable in rotation about a respective axis of rotation (0) between the first position and the second position, an air passage section in said second annular swirler (54-2) being smaller in the first position than in the second position of the second blades (62-2), wherein the rotary member (68) is rotatably coupled to said annular rows of first blades (62-1) and second blades (62-2) so as to simultaneously move in rotation the first blades (62-1) and the second blades (62-2) between the first position and the second position when said rotary member (68) is rotated.

14. Assembly according to the preceding claim, in which the number of first blades (62-1) is greater than the number of second blades (62-2).

15. The assembly of one of claims 13 or 14, further comprising a plurality of first rods (89), wherein each first rod (89) is integral with one of the first vanes (62-1) or one of the second vanes (62-2).

16. An assembly according to claim 2 and one of claims 13 to 15, further comprising a plurality of second rods (91), wherein each second rod (91) is integral with one of the first blades (62-1) and one of the second blades (62-2).

17. A turbomachine (100), such as a turbojet or a turboprop, comprising at least one turbomachine assembly (100) according to one of the preceding claims.

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