Propulsion assembly comprising at least one engine and one transmission system connected by an external coupling system, aircraft comprising at least one such propulsion assembly

Abstract

Propulsion assembly comprising at least one engine and one transmission system connected by an external coupling system, aircraft comprising at least one such propulsion assembly The invention relates to a propulsion assembly comprising: at least one electric motor (42), a transmission system (44), at least one coupling module (58) comprising a freewheel (64) interposed between internal and external shafts (60, 62) coupled by first and second coupling mechanisms (80) to the output (48) and input (52) shafts of the electric motor (42) and of the transmission system (44), at least one of the first and second coupling mechanisms (80) comprising an angle transmission (84), at least one hollow intermediate element (56) in which the output shaft (48) of the electric motor (42), the input shaft (52) of the transmission system (44) and the internal and external tubes (60, 62) are at least partially positioned.62) of the coupling module (58). This solution simplifies the assembly or disassembly of the coupling module (58). Figure 5,

Description

Title of the invention: Propulsion assembly comprising at least one engine and one transmission system connected by an external coupling system, aircraft comprising at least one such propulsion assembly

[0001] The present application relates to a propulsion assembly comprising at least one engine and one transmission system connected by an external coupling system as well as to an aircraft comprising at least one such propulsion assembly.

[0002] According to an embodiment visible in [Fig.l], an aircraft 10 comprises a fuselage 12, at least one wing 14 connected to the fuselage 12 as well as propulsion assemblies 16 connected to the wing 14 and arranged on either side of the fuselage 12. As illustrated in FIGS. 2 and 3, each propulsion assembly 16 comprises a propeller 18 which has an axis of rotation A18.

[0003] For the remainder of the description, a longitudinal direction is parallel to the axis of rotation A18 of the propeller 18. The concepts “front” and “rear” refer to the direction of air flow relative to the aircraft in flight, the air flowing in the longitudinal direction, from front to rear.

[0004] An electric type propulsion assembly comprises several electric motors 20 as well as a transmission system 22, such as a gearbox for example, configured to couple the electric motors 20 to the propeller 18.

[0005] As illustrated in [Fig. 3], the transmission system 22 comprises a first housing 24 which has, in the longitudinal direction, a front wall F24 oriented towards the propeller 18 and a rear wall F24' on which the electric motors 20 are fixed as well as at least one kinematic chain 26, positioned in the first housing 24, which has at least one input 28 for each electric motor 20 and an output 30, in the form of an output shaft, passing through the front wall F24 to be coupled to the propeller 18.

[0006] Each electric motor 20 has a second housing 32 which comprises a bearing face F32, fixed against the rear wall F24' of the first housing 24, as well as an output shaft 34, projecting relative to the bearing face F32, passing through the rear wall F24' of the first housing 24. This output shaft 34 is coupled with one of the inputs 28 of the kinematic chain 26 of the transmission system 22 by a coupling system 36 positioned in the first housing 24 of the transmission system 22.

[0007] According to one embodiment, each coupling system 36 comprises a freewheel configured to occupy a coupled state in which the output shaft 34 of the corresponding electric motor 20 is rotationally coupled and transmits a rotational movement to the kinematic chain 26 of the transmission system 22 as well as a decoupled state, in the event of an incident for example, in which the output shaft 34 of the corresponding electric motor 20 is no longer coupled to the kinematic chain 26 of the transmission system 22 and no longer transmits a rotational movement to it.

[0008] In this way, if an electric motor 20 no longer operates and its output shaft 34 is blocked in rotation, the coupling system 36 makes it possible to isolate it from the kinematic chain 26, which remains operational and transmits the rotational movements of the other electric motors 20 to the propeller 18.

[0009] The coupling systems 36 require more frequent maintenance operations than the other elements of the transmission system 22. For each of these, the transmission system 22 must be removed, which involves dismantling the electric motors 20, and its housing 24 must be opened in order to access the coupling systems 36. These different steps are relatively long, tedious and costly.

[0010] To overcome this drawback, document FR3139554 proposes a propulsion assembly 16 which has a remote coupling system 36'. According to an embodiment of this document visible in [Fig.4], each electric motor 20 has an output shaft 34' positioned at a rear face of the electric motor 20 opposite its front face connected to the transmission system 22. This output shaft 34' is hollow and configured to house the coupling system 36'. In addition, the latter comprises: a. a freewheel 36.1' which has a first part connected to the output shaft 34' of the electric motor 20 and a second part, b. a coupling shaft 36.2' passing through the electric motor 20 and connecting the second part of the freewheel 36.1' and the input 28' of the transmission system 22.

[0011] The coupling system 36' being offset relative to the transmission system 22 and located at the rear face of the electric motor 20, it is accessible so that it is no longer necessary to remove the transmission system and dismantle it to carry out a maintenance operation on the coupling system.

[0012] This solution is however not optimal because the coupling system 36' comprises a coupling shaft 36.2' which passes through the electric motor 20, which requires a modification of the latter.

[0013] The present invention aims to remedy all or part of the drawbacks of the prior art.

[0014] To this end, the invention relates to a propulsion assembly comprising at least one electric motor which has an output shaft and a pivot axis, a transmission system which has an input shaft and a second pivot axis as well as at least one coupling module connecting the output shaft of the electric motor and the input shaft of the transmission system; the coupling module comprising inner and outer shafts which are coaxial, spaced apart from each other and each have a first end and a third common pivot axis as well as a freewheel interposed between the inner and outer shafts.

[0015] According to the invention, the propulsion assembly comprises at least one hollow intermediate element in which the output shaft of the electric motor, the input shaft of the transmission system and the inner and outer tubes of the coupling module are at least partially positioned, a first coupling mechanism connecting the inner shaft and a first element from among the output shaft of the electric motor and the input shaft of the transmission system as well as a second coupling mechanism connecting the outer shaft and a second element, different from the first element, from among the output shaft of the electric motor and the input shaft of the transmission system, at least one of the first and second coupling mechanisms comprising an angle transmission.

[0016] This solution can be implemented without modification inside the electric motor and the transmission system and allows the coupling module to be dismantled or replaced quickly and simply without the need to dismantle the electric motor and / or the transmission system, thereby saving time for the maintenance of said coupling module.

[0017] According to another characteristic, the coupling module comprises a housing configured to house the internal and external shafts and the freewheel as well as a removable connection connecting said housing and the hollow intermediate element.

[0018] According to another characteristic, the housing comprises: a. a tubular body extending between first and second ends, the first end being open and facing toward the hollow intermediate member, b. a cover, configured to close the second end, connected to the body by a removable connection.

[0019] According to another characteristic, the coupling module comprises at least one rotational guidance system connecting the external shaft and the third housing as well as a set of stops for immobilizing the external shaft and the third housing relative to each other in translation in a direction parallel to the third pivot axis.

[0020] According to another characteristic, the coupling module comprises at least one locking element for immobilizing in translation, in a direction parallel to the third pivot axis, the internal shaft and the first element among the output shaft of the electric motor and the input shaft of the transmission system to which is coupled the internal shaft.

[0021] According to another characteristic, the third pivot axis of the coupling module and the first or second pivot axis of the first element among the output shaft and the input shaft to which the internal shaft is coupled are aligned. In addition, the first coupling mechanism is configured to immobilize in rotation relative to each other the internal shaft and the first element among the output shaft and the input shaft.

[0022] According to another characteristic, the first element among the output shaft of the electric motor and the input shaft of the transmission system to which the internal shaft is coupled comprises a housing configured to house the first end of the internal shaft.

[0023] According to another characteristic, the internal shaft is hollow. In addition, the locking element is an assembly screw which comprises a head bearing against the internal shaft as well as a rod housed in the internal tube, the rod having a threaded end configured to screw into a tapped hole provided at the housing of the first element among the output shaft and the input shaft to which the internal shaft is coupled.

[0024] According to another characteristic, the third pivot axis of the coupling module is perpendicular to the first and second pivot axes of the output shaft of the electric motor and of the input shaft of the transmission system. In addition, the first coupling mechanism comprises a first bevel gear which comprises a first bevel gear secured to the first end of the internal shaft as well as a second bevel gear secured to the first element among the output shaft of the electric motor and the input shaft of the transmission system to which the internal shaft is coupled, the first and second bevel gears being configured to cooperate and mesh with each other.

[0025] According to another characteristic, the locking element is a stop inserted between on the one hand the third housing and on the other hand the internal shaft and / or the first bevel gear secured to the internal shaft, said stop being configured to immobilize the internal shaft relative to the third housing so that the first and second bevel gears cooperate with each other.

[0026] According to another characteristic, the second coupling mechanism comprises a second angle transmission which comprises a first bevel gear secured to the external shaft as well as a second bevel gear secured to the second element among the output shaft of the electric motor and the input shaft of the transmission system to which the external shaft is coupled, the first and second bevel gears being configured to cooperate and mesh with each other.

[0027] According to a first variant, the hollow intermediate element is separate from the motor electrical and transmission system.

[0028] According to another variant, the hollow intermediate element forms a single and same part with the electric motor or the transmission system.

[0029] The invention also relates to an aircraft comprising at least one propulsion assembly according to one of the preceding characteristics.

[0030] Other characteristics and advantages will emerge from the description of the invention which follows, a description given by way of example only, with reference to the appended drawings, among which:

[0031] [Fig-1] is a side view of an aircraft,

[0032] [Fig.2] is a schematic side view of an electric propulsion assembly illustrating an embodiment of the prior art,

[0033] [Fig.3] is a schematic section of a transmission system and electric motors of a propulsion assembly illustrating an embodiment of the prior art,

[0034] [Fig.4] is a schematic section of a transmission system and electric motors of a propulsion assembly illustrating another embodiment of the prior art,

[0035] [Fig.5] is a schematic section of an electric motor and a transmission system connected by a coupling module illustrating an embodiment of the invention, the coupling module being in the mounted state,

[0036] [Fig.6] is a schematic section of an electric motor and a transmission system connected by a coupling module illustrating an embodiment of the invention, the coupling module being in the disassembled state,

[0037] [Fig.7] is a schematic section of an electric motor and a transmission system connected by a coupling module illustrating another embodiment of the invention,

[0038] [Fig.8] is a schematic section of an electric motor and a transmission system connected by a coupling module illustrating another embodiment of the invention,

[0039] [Fig.9] is a schematic section of an electric motor and a transmission system connected by a coupling module illustrating another embodiment of the invention.

[0040] According to an embodiment visible in Figures 5 and 9, an electric type propulsion assembly 40 comprises at least one electric motor 42 as well as a transmission system 44, such as a gearbox for example, configured to couple the electric motor 42 to a propulsion system such as a propeller for example.

[0041] According to one application, an aircraft comprises at least one such propulsion assembly 40. Of course, the invention is not limited to this application.

[0042] Each electric motor 42 comprises a first housing 46 which has a first end face 46.1 and an output shaft 48, which has a first pivot axis A48, connected to the first housing 46 by a pivoting connection projecting from the first end face 46.1. According to one arrangement, the first end face 46.1 is substantially perpendicular to the first pivot axis A48. The output shaft 48 has a free end 48.1 spaced from the first end face 46.1.

[0043] Each transmission system 44 comprises a second housing 50 which has a second front face 50.1 as well as an input shaft 52, which has a second pivot axis A52, connected to the second housing 50 by a pivoting connection projecting relative to the second front face 50.1. According to one arrangement, the second front face 50.1 is substantially perpendicular to the second pivot axis A52. The input shaft 52 has a free end 52.1 spaced from the second front face 50.1.

[0044] The electric motor 42 and the transmission system 44 are stationary relative to each other.

[0045] According to a first arrangement visible in Figures 8 and 9, the electric motor 42 and the transmission system 44 are connected by fixing elements to the same hollow intermediate support 54 separate from the electric motor 42 and the transmission system 44. According to one embodiment, the first and second pivot axes A48, A52 are substantially parallel to each other. In addition, the hollow intermediate support 54 is a cylindrical tube which has an axis substantially parallel to the first and second pivot axes A48, A52 and extends between first and second ends 54.1, 54.2 which are open and respectively provided with first and second flanges C54.1, C54.2, the electric motor 42 being connected to the first flange C54.1, the transmission system 44 being connected to the second flange C54.2.According to this embodiment, the output shaft 48 of the electric motor 42 and the input shaft 52 of the transmission system 44 are positioned inside the hollow intermediate support 54.

[0046] According to a second arrangement visible in Figures 5 to 7, the electric motor 42 and the transmission system 44 are directly connected to each other. According to one embodiment, the transmission system 44 comprises a hollow extension 56 which has an opening 56.1 to allow the passage of the output shaft 48 of the electric motor 42, the electric motor 42 being located outside the hollow extension 56 and connected to the hollow extension 56 around the lateral opening 56.1. According to this embodiment, the output shaft 48 of the electric motor 42 and the input shaft 52 of the transmission system 44 are positioned inside the hollow extension 56.

[0047] Of course, the invention is not limited to these arrangements. Whatever the arrangement, the propulsion assembly 40 comprises a hollow intermediate element, such as the hollow intermediate support 54 or the hollow extension 56, integral with the electric motor 42 and the transmission system 44, in which are positioned, at least partially, the output shaft 48 of the electric motor 42 and the input shaft 52 of the transmission system 44.

[0048] According to certain embodiments visible in Figures 8 and 9, the hollow intermediate element is separate from the electric motor 42 and the transmission system 44.

[0049] According to other embodiments visible in Figures 5 to 7, the hollow intermediate element forms only one single part with the electric motor 42 or the transmission system 44.

[0050] The propulsion assembly 40 comprises at least one coupling module 58 connecting the output shaft 48 of the electric motor 42 and the input shaft 52 of the transmission system 44. Each coupling module 58 comprises coaxial and spaced apart inner and outer shafts 60, 62 as well as a freewheel 64 interposed between the inner and outer shafts 60, 62 and connecting them, said freewheel 64 being configured to occupy a coupled state in which a first shaft among the inner and outer shafts 60, 62 is rotationally coupled and transmits a rotational movement to a second shaft different from the first shaft among the inner and outer shafts 60, 62 as well as an uncoupled state, in the event of an incident for example, in which the first shaft is no longer coupled to the second shaft and no longer transmits a rotational movement to it.The coupling module 58 has a third pivot axis A58 merged with the pivot axes of the inner and outer shafts 60, 62. Each of the inner and outer shafts 60, 62 comprises a first end 60.1, 62.1 oriented towards the electric motor 42 and / or the transmission system 44 as well as a second end 60.2, 62.2 opposite the first end 60.1, 62.1. The outer shaft 62 is hollow to house the inner shaft 60 and the freewheel 64.

[0051] According to one embodiment, the coupling module 58 comprises at least one first rotational guidance system 66 connecting the inner and outer shafts 60, 62 and allowing the latter to pivot relative to each other around the third pivot axis A58. According to one configuration, the first rotational guidance system 66 comprises at least two bearings 66.1, 66.1' positioned on either side of the freewheel 64. The coupling module 58 comprises a pair of stops 66.2, 66.2', positioned on either side of the bearings 66.1, 66.1', to immobilize in translation in a direction parallel to the third pivot axis A58 the first guidance system 66 and the freewheel 64 relative to the outer shaft 62.

[0052] According to one embodiment, the internal shaft 60 has an external surface S60 which comprises an internal track of the freewheel 64 and / or the external shaft 62 has an internal surface S62 which comprises an external track of the freewheel 64.

[0053] According to one configuration, the coupling module 58 comprises a third housing 68 configured to house the inner and outer shafts 60, 62 as well as the freewheel 64. This third housing 68 comprises a tubular and cylindrical body 70 which extends between first and second ends 70.1, 70.2, the first end 70.1 being open and oriented towards the hollow intermediate element 54, 56.

[0054] According to one configuration, the second end 70.2 is closed to protect the internal and external shafts 60, 62 as well as the freewheel 64. According to one embodiment, the third housing 68 comprises a cover 72 configured to close the second end 70.2, said cover 72 being connected to the body 70 by a removable connection 74 such as a plurality of fixing elements distributed over the periphery of the cover 72. According to one arrangement, the coupling module 58 comprises at least one seal 75 interposed between the body 70 and the cover 72 to obtain a sealed connection between these two elements.

[0055] According to one embodiment, the coupling module 58 comprises at least one second rotational guidance system 76, connecting the external shaft 62 and the third housing 68, which is positioned between the external shaft 62 and the body 70 and allows the latter to pivot relative to each other around the third pivot axis A58. According to one configuration, the second rotational guidance system comprises two bearings 76.1, 76.1' positioned near the first and second ends 70.1, 70.2 of the body 70. The coupling module 58 comprises a first pair of stops, positioned on either side of the bearings 76.1, 76.1', to immobilize in translation in a direction parallel to the third pivot axis A58 the second guidance system 76 relative to the external shaft 62 as well as a second pair of stops, positioned between the bearings 76.1, 76.1', to immobilize in translation in a direction parallel to the third pivot axis A58 the second guide system 76 relative to the third housing 68. In general, the coupling module 58 comprises a set of stops to immobilize the external shaft 62 and the third housing 68 relative to each other in translation in a direction parallel to the third pivot axis A58.

[0056] According to one arrangement, the coupling module 40 and more particularly its third housing 68 is connected to the hollow intermediate element 54, 56 by a removable connection 78. According to one embodiment, the first end 70.1 of the body 70 is connected to the hollow intermediate element 54, 56 by the removable connection 78 which comprises a plurality of fixing elements distributed over the circumference of the first end 70.1. According to one arrangement, the coupling module 58 comprises at least one seal 79 interposed between the third housing 68 and the hollow intermediate element 54, 56 to obtain a sealed connection between these two elements.

[0057] Of course, the invention is not limited to these embodiments for the module coupling 58. Whatever the embodiment, the propulsion assembly 40 comprises at least one hollow intermediate element 54, 56 in which are at least partially positioned the output shaft 4 of the electric motor 42, the input shaft 52 of the transmission system 44 as well as the internal and external shafts 60, 62 of the coupling module 58 so that the latter cooperate with the output and input shafts 48, 52 of the electric motor 42 and of the transmission system 44.

[0058] The propulsion assembly 40 comprises a first coupling mechanism 80 connecting the internal shaft 60 and a first element among the output shaft 48 of the electric motor 42 and the input shaft 52 of the transmission system 44 as well as a second coupling mechanism 82 connecting the external shaft 62 and a second element, different from the first element, among the output shaft 48 of the electric motor 42 and the input shaft 52 of the transmission system 44.

[0059] According to a feature of the invention, the third pivot axis A58 of the coupling module 58 intersects with at least one of the first and second pivot axes A48, A52. In addition, at least one of the first and second coupling mechanisms 80, 82 comprises an angle transmission 84.

[0060] According to a first embodiment visible in Figures 5 and 6, the third pivot axis A58 of the coupling module 58 is perpendicular to the first pivot axis A48 of the output shaft 48 of the electric motor 42 and aligned with the second pivot axis A52 of the input shaft 52 of the transmission system 44. According to this first embodiment, the first coupling mechanism 80 connects the internal shaft 60 of the coupling module 58 and the input shaft 52 of the transmission system 44. This input shaft 52 comprises, at its free end 52.1, a housing 86 configured to house the first end 60.1 of the internal shaft 60. The first coupling mechanism 80 allows the internal shaft 60 to rotate the input shaft 52. According to one configuration, the housing 86 of the shaft inlet 52 and the first end 60.1 of the internal shaft 60 respectively comprise female and male splines configured to cooperate with each other and allow rotational driving of the input shaft 52 by the internal shaft 60.

[0061] According to this first embodiment, the internal shaft 60 is hollow. The coupling module 58 comprises at least one locking element 88 for immobilizing in translation in a direction parallel to the third pivot axis A58 the internal shaft 60 and the first element among the output shaft 48 of the electric motor 42 and the input shaft 52 of the transmission system 44 to which the internal shaft 60 is coupled. According to one configuration, this locking element 88 is an assembly screw which comprises a head 88.1 bearing against the second end 60.2 of the internal shaft 60 as well as a rod 88.2 housed in the internal tube 60 and having a threaded end 88.3 configured to be screwed into a tapped hole 86.1 provided at the housing 86 of the input shaft 52 of the transmission system 44. This assembly screw makes it possible to immobilize in translation, in a direction parallel to the second pivot axis A52, the internal shaft 60 and the input shaft 52.

[0062] According to this first embodiment, the first coupling mechanism 80 comprises a first part, such as the male and female splines, for immobilizing the internal shaft 60 and the external shaft 62 in rotation relative to each other, and a second part, such as the assembly screw, for immobilizing the internal shaft 60 and the input shaft 52 in translation. Of course, the invention is not limited to this embodiment. Thus, the first coupling mechanism 80 may comprise a single means, such as a transverse pin, for immobilizing the internal shaft 60 and the input shaft 52 in rotation and translation relative to each other.

[0063] According to this first embodiment, the second coupling mechanism 82 comprises a bevel gear 84 which comprises a first bevel gear 84.1, such as a crown, secured to the first end 62.1 of the external shaft 62 as well as a second bevel gear 84.2, such as a bevel pinion, secured to the output shaft 48 of the electric motor 42, the first and second bevel gears 84.1, 84.2 being configured to cooperate and mesh with each other.

[0064] According to this first embodiment, the transmission system 44 comprises a hollow extension 56 which has at least a first face F56, substantially parallel to the second pivot axis A52 of the input shaft 52 of the transmission system 44, at which a first opening 56.1 is provided as well as a second face F56', substantially perpendicular to the second pivot axis A52 of the input shaft 52 of the transmission system 44, at which a second opening 56.2 is provided, the first face F56 being positioned between the second housing 50 of the transmission system 44 and the second face F56' of the hollow extension 56. In addition, the first housing 46 of the electric motor 42 is connected to the hollow extension 56 around the first opening 56.1, the output shaft 48 of the electric motor 42 passing through the first opening 56.1.The third housing 68 of the coupling module 58 is connected to the hollow extension 56, around the second opening 56.2, by means of fixing elements 56.3 of the removable connection 78.

[0065] As illustrated in [Fig.6], the coupling module 58 is disassembled in the following manner:

[0066] Firstly, the cover 72 is removed by removing the fixing elements of the removable connection 74.

[0067] Next, the locking element 88 as well as the fixing elements 56.3 of the removable connection 78 are removed.

[0068] From then on, the coupling module 58 can be removed.

[0069] Reassembly of the coupling module 58 is carried out in the reverse order, replacing the sealing gaskets 75, 79 if necessary.

[0070] According to a second embodiment visible in [Fig. 7], the third pivot axis A58 of the coupling module 58 is aligned with the first pivot axis A48 of the output shaft 48 of the electric motor and substantially perpendicular to the second pivot axis A52 of the input shaft 52 of the transmission system 44. According to this second embodiment, the first coupling mechanism 80 connects the internal shaft 60 of the coupling module 58 and the output shaft 48 of the electric motor 42. This output shaft 48 comprises, at its free end 48.1, a housing 86' configured to house the first end 60.1 of the internal shaft 60. It may be identical to that visible in FIGS. 5 and 6 connecting the internal shaft 60 and the input shaft 52 of the transmission system 44.

[0071] According to this second embodiment, the second coupling mechanism 82 comprises a bevel gear 84 which comprises a first bevel gear 84.1, such as a bevel gear, secured to the first end 62.1 of the external shaft 62 as well as a second bevel gear 84.2, such as a bevel pinion, secured to the input shaft 52 of the transmission system 44, the first and second bevel gears 84.1, 84.2 being configured to cooperate and mesh with each other.

[0072] According to this second embodiment, the transmission system 44 comprises a hollow extension 56 which has at least a first face F56, substantially parallel to the second pivot axis A52 of the input shaft 52 of the transmission system 44, at which a first opening 56.1 is provided, as well as a second face F56', substantially parallel to the second pivot axis A52 of the input shaft 52 of the transmission system 44, at which a second opening 56.2 is provided. In addition, the first housing 46 of the electric motor 42 is connected to the hollow extension 56, the output shaft 48 of the electric motor 42 passing through the first opening 56.1. The third housing 68 of the coupling module 58 is connected to the hollow extension 56, around the second opening 56.2, by means of fixing elements 56.3 of the removable connection 78.

[0073] According to a third embodiment visible in [Fig. 8], the electric motor 42 and the transmission system 44 are arranged so that the first and second pivot axes A48, A52 are substantially parallel to each other and aligned. In addition, the third pivot axis A58 of the coupling module 58 is substantially perpendicular to the first and second pivot axes A48, A52 of the output and input shafts 48, 52 of the electric motor 42 and of the transmission system 44. According to this third embodiment, the first coupling mechanism 80 comprises a first angle transmission 84 which comprises a first bevel gear 84.1 secured to the first end 60.1 of the internal shaft 60 as well as a second bevel gear 84.2 secured to the input shaft 52 of the transmission system 44, the first and second bevel gears 84.1, 84.2 being configured to cooperate and mesh with each other. In addition, the second coupling mechanism 82 comprises a second angle transmission 84' which comprises a first bevel gear 84.1' secured to the first end 62.1 of the external shaft 62 as well as a second bevel gear 84.2' secured to the output shaft 48 of the electric motor 42, the first and second bevel gears 84.1', 84.2' being configured to cooperate and mesh with each other.

[0074] According to the third embodiment, the coupling module 58 comprises at least one locking element 90 for immobilizing in translation in a direction parallel to the third pivot axis A58 the internal shaft 60 and the first element among the output shaft 48 of the electric motor 42 and the input shaft 52 of the transmission system 44 to which the internal shaft 60 is coupled. According to one configuration, this locking element 90 is a stop interposed between the third housing 68, more particularly its cover 72, and the internal shaft 60 and / or the first bevel gear 84.1 secured to the first end 60.1 of the internal shaft 60. This stop is configured to immobilize the internal shaft 60 relative to the third housing 68 so that the first and second bevel gears 84.1, 84.2, secured respectively to the internal shaft 60 and the input shaft 52 of the transmission 44, cooperate with each other.

[0075] According to this third embodiment, the propulsion assembly 40 comprises a hollow intermediate support 54 which has at least a first face F54, substantially perpendicular to the first pivot axis A48 of the output shaft 48 of the electric motor 42, at which a first opening 92.1 is provided, a second face F54', substantially parallel to the first face F54 and perpendicular to the second pivot axis A52 of the input shaft 52 of the transmission system 44, at which a second opening 92.2 is provided as well as a third face F54”, substantially perpendicular to the first and second faces F54, F54' and located between the latter, at which a third opening 92.3 is provided. In addition, the first housing 46 of the electric motor 42 is connected to the hollow intermediate support 54 around the first opening 92.1, the output shaft 48 of the electric motor 42 passing through the first opening 92.1.The second housing 50 of the transmission system 44 is connected to the hollow intermediate support 54 around the second opening 92.3, the input shaft 52 of the transmission system 44 passing through the second opening 92.2. The third housing 68 of the coupling module 58 is connected to the hollow intermediate support 54, around the . third opening 92.3, thanks to fixing elements distributed around the third opening 92.3.

[0076] According to a fourth embodiment visible in [Fig. 8], the electric motor 42 and the transmission system 44 are arranged so that the first and second pivot axes A48, A52 are substantially parallel to each other and offset from each other. The other elements of the coupling module 58 may be identical to those of the third embodiment.

[0077] According to the third and fourth embodiments, the coupling module 58 is removed by removing the fastening elements which connect the third housing 68 of the coupling module 58 and the hollow intermediate support 54.

[0078] Whatever the embodiment, it is possible to dismantle or replace the coupling module 58 quickly and simply without needing to dismantle the electric motor 42 and / or the transmission system 44, which makes it possible to save time for the maintenance of said coupling module 58.

[0079] According to another advantage, the propulsion assembly 40 comprises an electric motor 42 and / or a transmission system 44 without any modification inside the first and second housings 46, 50 compared to those of the prior art.

Claims

Claims

1. A propulsion unit comprising at least one electric motor (42) which has an output shaft (48) and a pivot axis (A48), a transmission system (44) which has an input shaft (52) and a second pivot axis (52) and at least one coupling module (58) connecting the output shaft (48) of the electric motor (42) and the input shaft (52) of the transmission system (44), the coupling module comprising inner and outer shafts (60, 62) which are coaxial, spaced apart from each other and each have a first end (60.1, 62.2) and a third common pivot axis (A58) as well as a freewheel (64) interposed between the inner and outer shafts (60, 62);characterized in that the propulsion assembly (40) comprises at least one hollow intermediate element (54, 56) in which are at least partially positioned the output shaft (48) of the electric motor (42), the input shaft (52) of the transmission system (44) as well as the internal and external tubes (60, 62) of the coupling module (58), a first coupling mechanism (80) connecting the internal shaft (60) and a first element among the output shaft (48) of the electric motor (42) and the input shaft (52) of the transmission system (44) as well as a second coupling mechanism (82) connecting the external shaft (62) and a second element, different from the first element, among the output shaft (48) of the electric motor (42) and the input shaft (52) of the transmission system (44), at least one of the first and second coupling mechanisms (80, 82) comprising a return corner (84).;

2. Propulsion assembly according to the preceding claim, characterized in that the coupling module (58) comprises a housing (68) configured to house the internal and external shafts (60, 62) and the freewheel (64) as well as a removable connection (78) connecting said housing (68) and the hollow intermediate element (54, 56).

3. Propulsion assembly according to the preceding claim, characterized in that the housing (68) comprises: a. a tubular body (70) which extends between first and second ends (70.1, 70.2), the first end (70.1) being open and oriented towards the hollow intermediate element (54, 56), b. a cover (72) configured to close the second end (70.2) and connected to the body (70) by a removable connection (74).

4. Propulsion assembly according to one of claims 2 to 3, characterized in that the coupling module (58) comprises at least one rotational guide system (76) connecting the external shaft (62) and the third housing (68) as well as a set of stops for immobilizing the external shaft (62) and the third housing (68) relative to each other in translation in a direction parallel to the third pivot axis (A58).

5. Propulsion assembly according to one of the preceding claims, characterized in that the coupling module (58) comprises at least one locking element (88, 90) for immobilizing in translation, in a direction parallel to the third pivot axis (A58), the internal shaft (60) and the first element among the output shaft (48) of the electric motor (42) and the input shaft (52) of the transmission system (44) to which the internal shaft (60) is coupled.

6. Propulsion assembly according to one of the preceding claims, characterized in that the third pivot axis (A58) of the coupling module (58) and the first or second pivot axis (A48, A52) of the first element among the output shaft (48) and the input shaft (52) to which the internal shaft (60) is coupled are aligned and in that the first coupling mechanism (80) is configured to immobilize in rotation relative to each other the internal shaft (60) and the first element among the output shaft (48) and the input shaft (52).

7. Propulsion assembly according to the preceding claim, characterized in that the first element among the output shaft (48) of the electric motor (42) and the input shaft (52) of the transmission system (44) to which the internal shaft (60) is coupled comprises a housing (86) configured to house the first end (60.1) of the internal shaft (60).

8. Propulsion assembly according to claims 5 and 7, characterized in that the internal shaft (60) is hollow and in that the locking element (88) is an assembly screw which comprises a head (88.1) bearing against the internal shaft (60) as well as a rod (88.2) housed in the internal tube (60), the rod (88.2) having a threaded end (88.3) configured to screw into a tapped hole (86.1) provided at the housing (86) of the first element among the output shaft (48) and the input shaft (52) to which the internal shaft (60) is coupled.

9. Propulsion assembly according to one of claims 1 to 5, characterized in that the third pivot axis (A58) of the coupling module (58) is perpendicular to the first and second pivot axes (A48, A52) of the output shaft (48) of the electric motor (42) and of the input shaft (52) of the transmission system (44) and in that the first coupling mechanism (80) comprises a first bevel gear (84) which comprises a first bevel gear (84.1) secured to the first end (60.1) of the internal shaft (60) as well as a second bevel gear (84.2) secured to the first element among the output shaft (48) of the electric motor (42) and the input shaft (52) of the transmission system (44) to which the internal shaft (60) is coupled, the first and second bevel gears (84.1, 84.2) being configured to cooperate and mesh with each other.

10. Propulsion assembly according to one of claims 5 to 9, characterized in that the locking element (90) is a stop interposed between on the one hand the third housing (68) and on the other hand the internal shaft (60) and / or the first bevel gear (84.1) secured to the internal shaft (60), said stop being configured to immobilize the internal shaft (60) relative to the third housing (68) so that the first and second bevel gears (84.1, 84.2) cooperate with each other.

11. Propulsion assembly according to one of the preceding claims, characterized in that the second coupling mechanism (82) comprises a second bevel gear (84') which comprises a first bevel gear (84.1') secured to the external shaft (62) as well as a second bevel gear (84.2') secured to the second element among the output shaft (48) of the electric motor (42) and the input shaft (52) of the transmission system (44) to which the external shaft (62) is coupled, the first and second bevel gears (84.1', 84.2') being configured to cooperate and mesh with each other.

12. Propulsion assembly according to one of the preceding claims, characterized in that the hollow intermediate element (54) is separate from the electric motor (42) and the transmission system (44).

13. Propulsion assembly according to one of claims 1 to 11, characterized in that the hollow intermediate element (56) forms a single and same part with the electric motor (42) or the transmission system (44).

14. Aircraft comprising at least one propulsion unit according to one of the preceding claims.

Images