Movement transmission device for an aircraft

Abstract

The invention relates to a movement transmission device (10) for a mechanism for actuating and / or opening and / or closing and / or locking and / or unlocking a door or a flap of a mechanical movement control device of an aircraft, the device (10) comprising a transmission shaft (20) extending along a longitudinal axis (A). The transmission shaft (20) comprises at least one fastening segment (22). The movement transmission device (10) further comprises a transmission element (40) fastened to the fastening segment (22). The fastening segment (22) has a cross section that is a non-circular in a plane orthogonal to the longitudinal axis (A) and comprises at least one fastening surface (24). The transmission element (40) comprises a complementary fastening surface (42) that corresponds to the planar fastening surface (24). The transmission shaft (20) is made of a composite material and the transmission element (40) is made of a metal material.

Description

[0001] Title: Motion transmission device for an aircraft

[0002] The present invention relates to the field of motion transmission devices, and more particularly to the field of transmission devices comprising a transmission shaft and one or more transmission elements arranged on the shaft.

[0003] Such transmission devices are generally used for actuation, i.e. opening, closing, locking and / or unlocking of a mechanical control device of an aircraft such as a door, a flap, an angle gear or a flight control of an aircraft such as an airplane.

[0004] The transmission elements arranged on the shaft can consist of bearings often made by the presence of rollers, lever arms allowing the rotation of the shaft to be transformed into circular movement of the end of the levers, pinions, cams or any other type of transmission elements.

[0005] The drive shafts of such known transmission devices are mostly rotationally guided and serve to transmit movements via the transmission elements, also called accessories.

[0006] The transmission shafts of such known transmission devices are mostly metallic and tubular in shape, the accessories or transmission elements are generally secured by a cylindrical adjustment associated with a radial pin allowing locking in rotation around a longitudinal axis of the transmission shaft and relative translation in a direction parallel to the longitudinal axis. A double pinning most of the time makes it possible to ensure redundancy of the fixing. Such a transmission device is for example known from document EP 0 743 240 B1.

[0007] Such a known transmission device has in particular the following disadvantages: the presence of the pins requires radial drilling of the transmission shaft, which reduces the resistant section of the transmission shaft while presenting a shape accident capable of concentrating stresses in this zone when the shaft is stressed; the transmission, of the mechanical actions being carried out via the pins concentrates the forces of the pins on the transmission shaft in the zone already most loaded by the torsion of the transmission shaft; this concentration of resistance problems in the pinning zones of the transmission shaft leads to an oversizing of the mechanical parts and therefore to a mass of the entire transmission device mounted not being optimal.

[0008] One way to avoid or reduce the extent of these disadvantages could be to transmit the mechanical actions via splines or to produce integral shafts on which the accessories are formed from a single piece by machining or 3D metal printing for example.

[0009] This solution nevertheless has the disadvantage of making detachment or replacement of accessories difficult or impossible.

[0010] Transmission devices are also known which are intended to be joined to the free end of a hollow shaft, the connection being made by introducing a part of the transmission device into said shaft, while there is concordance of the external profile of said part with the internal profile of said free end. These devices also have the disadvantage of difficult or impossible detachment or replacement of the accessories.

[0011] It is an object of the present application to propose a transmission device allowing easy detachment or replacement of the transmission elements or accessories. It is further an object of the present application to propose a transmission device which is light in weight, inexpensive to produce and avoids areas of concentration of mechanical stresses in a transmission shaft of the transmission device.

[0012] To this end, the present invention relates to a movement transmission device for an actuating and / or opening and / or closing and / or locking and / or unlocking mechanism of a mechanical movement control device such as a door, a flap, an angle gear or a flight control of an aircraft. The transmission device comprises a transmission shaft extending along a longitudinal axis. The transmission shaft comprises at least one fixing section. The transmission device further comprises a transmission element fixed to the fixing section. The fixing section has a non-circular cross-section in a plane orthogonal to the longitudinal axis and comprises at least one fixing surface. The transmission element further comprises a complementary fixing surface matching the fixing surface.According to the invention, the transmission shaft is made of a composite material, preferably a composite material comprising carbon fibers, while the transmission element is made of a metallic material, preferably aluminum, and it comprises a fitting part, fitted onto said fixing section, while at least one clamping screw makes it possible to tighten the fitting part against the fixing section.

[0013] The use of a composite material makes it possible to obtain a transmission device which is light in weight and sufficiently rigid.

[0014] According to one possibility, the attachment surface and the complementary attachment surface are essentially planar and each extend in a plane parallel to the longitudinal axis.

[0015] According to a preferred embodiment, the fixing section comprises in a plane orthogonal to the longitudinal axis a cross-section of essentially polygonal shape, preferably of the shape of an equilateral and / or equiangular polygon. These characteristics allow an easy and rigid connection between the transmission element and the transmission shaft.

[0016] According to a possible additional feature, the drive shaft is a tubular element.

[0017] This feature also makes it possible to obtain a transmission device which is of reduced weight and sufficiently rigid.

[0018] According to one possibility, the transmission element comprises a pin forming a mechanical obstacle to a movement of the transmission element along the transmission shaft parallel to the longitudinal axis.

[0019] According to a preferred embodiment, the transmission element and / or the transmission shaft each comprise a bore in which the pin is received, the bore of the transmission element preferably being arranged in the fitting part and / or the bore of the transmission shaft preferably being arranged in the fixing surface.

[0020] These features allow the transmission element to be locked against translational movement of the transmission element along the longitudinal axis of the transmission shaft.

[0021] According to a possible additional feature, the transmission device further comprises an adhesive connecting the transmission element to the fixing section.

[0022] The invention also relates to an aircraft, preferably an airplane comprising a transmission device according to the invention.

[0023] The invention will be better understood from the following description, which relates to two preferred embodiments, given by way of non-limiting example, and explained with reference to the appended schematic drawings, in which:

[0024] - Figure 1 is a schematic representation of a transmission shaft of a transmission device according to a first preferred embodiment of the invention; - Figure 2 is a schematic representation of a mold allowing the manufacture of the transmission shaft of the transmission device according to the first preferred embodiment of the invention;

[0025] - Figure 3 is a sectional view of the mold allowing the manufacture of the transmission shaft of the transmission device according to the first preferred embodiment of the invention;

[0026] - Figure 4 is a schematic representation of a transmission element of a transmission device according to the first preferred embodiment of the invention;

[0027] - Figure 5 is a schematic representation of the transmission device according to the first preferred embodiment of the invention;

[0028] - Figure 6 is a sectional view of the transmission device according to the first preferred embodiment of the invention; Figure 7 is a sectional view of the transmission device according to the first preferred embodiment of the invention;

[0029] - Figure 8 is a schematic representation of the transmission element of the transmission device according to the first preferred embodiment of the invention; Figure 9 is a perspective view of the transmission device according to the first preferred embodiment of the invention;

[0030] - Figure 10 is a sectional view of the transmission device according to the first preferred embodiment of the invention;

[0031] - Figure 11 is a sectional view of the transmission device according to the first preferred embodiment of the invention;

[0032] - Figure 12 is a perspective view of a sheet metal holding the transmission element of the transmission device according to the first preferred embodiment of the invention; - Figure 13 is a schematic representation of a variant of the transmission element of a transmission device according to the preferred embodiment of the invention;

[0033] - Figure 14 is a sectional view of the transmission device according to a second preferred embodiment of the invention.

[0034] The present application relates to a movement transmission device 10 for an actuation and / or opening and / or closing and / or locking and / or unlocking mechanism of a mechanical movement control device such as a door, a valve, an angle gear or a flight control of an aircraft. The present application also relates to an aircraft comprising a mechanism for actuation and / or opening and / or closing and / or locking and / or unlocking a mechanical movement control device such as a door, a valve, an angle gear or a flight control provided with such a movement transmission device 10. The movement transmission device 10 comprises a transmission shaft 20 extending along a longitudinal axis A. The transmission shaft 20 comprises at least one fixing section 22.The motion transmission device 10 further comprises a transmission element 40 fixed to the fixing section 22. The fixing section 22 has a non-circular cross-section in a plane orthogonal to the longitudinal axis A and comprises a fixing surface 24. The transmission element 40 comprises a complementary fixing surface 42 matching the fixing surface 24.

[0035] The fixing surface 24 as well as the complementary fixing surface 42 matching the fixing surface 24 prevent relative rotation around the longitudinal axis A between the transmission element 40 and the transmission shaft 20. The transmission element 40 is held on the fixing section 22 by shape matching.

[0036] According to one possibility, the attachment surface 24 and the complementary attachment surface 42 may be essentially planar and each extend in a plane parallel to the longitudinal axis A.

[0037] Alternatively, the fixing surface 24 and the complementary fixing surface 42 may be of curvilinear shape, preferably having a cross-section in a plane orthogonal to the longitudinal axis A in the shape of an arc of a circle, the center of which is distant from the longitudinal axis A, that is to say the center of which is not coincident with the longitudinal axis A.

[0038] The transmission elements 40 may consist of bearings often produced by the presence of rolling bearings, lever arms making it possible to transform the rotation of the transmission shaft 20 into circular movement of the end of the levers, pinions, cams or any other type of transmission elements. Figure 11 discloses a motion transmission device 10 provided with a transmission element 40 produced in the form of a rolling bearing.

[0039] The transmission elements 40 may be adapted for attachment sections 22 arranged on a central portion 23 of the transmission shaft 20 or may be adapted for attachment sections 22 arranged on an end portion 25 of the transmission shaft 20. The transmission elements 40 intended to be attached to attachment sections 22 arranged on the end portion 25 of the transmission shaft 20 may have a bearing surface 43 capable of bearing against an end face 27 of the transmission shaft 20 present on the end portion 25 of the transmission shaft 20. The bearing surface 43 and the end face 27 thus form a bearing preventing movement of the transmission element 40 on the transmission shaft 20 along the longitudinal axis A. Figure 13 discloses such a transmission element 40 intended to be attached to a fixing section 22 arranged on the end part 25 of the transmission shaft 20.

[0040] The transmission shaft 20 is made of a composite material, preferably a composite material comprising carbon fibers. The transmission element 40 is made of a metallic material, preferably aluminum.

[0041] The fixing section 22 may comprise, in a plane orthogonal to the longitudinal axis A, a cross-section of essentially polygonal shape, preferably of the shape of an equilateral and / or equiangular polygon.

[0042] In the first preferred embodiment of the invention, as disclosed in Figures 1 to 3, 5 to 7 and 9 to 11 for example, the fixing section 22 may comprise a section in the shape of an equilateral and equiangular hexagon.

[0043] In the second preferred embodiment of the invention, as disclosed in Figure 13, the fixing section 22 may have a cross-section in the shape of an ellipse.

[0044] The transmission shaft 20 may be a tubular element provided with a hollow 21. The hollow 21 may comprise, in a plane orthogonal to the longitudinal axis A, a cross-section of essentially polygonal shape, preferably of the shape of an equilateral and / or equiangular polygon. According to a preferred variant of the invention, the hollow 21 may comprise the shape of the same polygon as the fixing section 22.

[0045] According to an alternative, the hollow 21 may comprise in a plane orthogonal to the longitudinal axis A a cross-section of essentially round shape.

[0046] The transmission shaft 20 and / or the hollow 21 may have a constant section over their entire length in a plane orthogonal to the longitudinal axis A. In this case, a single continuous fixing section 22 over the entire length of the transmission shaft 20 or a series of several consecutive fixing sections 22 over the length of the transmission shaft 20 may be formed.

[0047] The transmission element 40 may comprise a fitting portion 44 fitted onto the fixing section 22 and a clamping screw 46 for tightening the fitting portion 44 against the fixing section 22. The complementary fixing surface 42 may be provided on the fitting portion 44. This assembly makes it possible to prestress the fitting portion 44 to fix the transmission element 40 to the fixing section 22 by friction between the fixing surface 24 and the complementary fixing surface 42.

[0048] The fitting portion 44 may have a plurality of complementary fixing surfaces 42, preferably non-parallel to each other. The number of complementary fixing surfaces 42 is preferably equal to the number of flat fixing surfaces 24 provided on the fixing section 22 of the transmission shaft 20. The fitting portion 44 may, in cross section, have the shape of the same polygon as the fixing section 22.

[0049] The transmission shaft 20 may have edge fillets on its outer surface in order to limit the areas of potential stress concentration on the transmission shaft 20.

[0050] The transmission element 40 may comprise a pin 48 forming a mechanical obstacle to a movement of the transmission element 40 along the transmission shaft 20 parallel to the longitudinal axis A.

[0051] The transmission element 40 and / or the transmission shaft 20 may each have a bore 50, 26 in which the pin 48 is received, the bore 50 of the transmission element 40 preferably being arranged in the fitting part 44 and / or the bore 26 of the transmission shaft 20 preferably being arranged in the fixing surface 24.

[0052] The pin 48 can be held in the bores 50, 26 using a holding plate 54. The holding plate 54 can be provided with an opening receiving the pin 48. The holding plate 54 can be fixed to the transmission element 40, preferably to the fitting part 44 of the transmission element 40 using a fixing screw 56 screwed into a tapped hole 58 of the transmission element 40.

[0053] The movement transmission device 10 may further comprise an adhesive 60 connecting the transmission element 40 to the fixing section 22. The transmission element 40 may comprise a hole 52 for injecting the adhesive 60. The hole 52 may open into the complementary fixing surface 42. The hole 52 may be arranged in the fitting part 44.

[0054] The polygonal-shaped fixing section 22 allows a multiplication of the stress zones in the transmission shaft 20, which promotes the progressiveness of the local loading between the transmission shaft 20 and the transmission element 40.

[0055] With regard to a torsion of the transmission shaft 20, the cross-section polar inertia of the fixing section 22 corresponds to the accumulation of the polar inertias of the transmission shaft 20 and of the transmission element 40. As a result, the torsional rigidity of the fixing section 22 is greater and the shear stress due to the torsion is lower. With regard to a bending of the transmission shaft 20, the cross-section inertias accumulate in the same way and therefore have the same beneficial effect. This property makes it possible to envisage pinning in the fixing surface 42, preferably in a central part of the fixing surface 42, without the pinning causing over-stresses, the tightening of the transmission element 40 reinforces this central part of the fixing surface 42.This pinning does not in any way reduce the performance of the transmission device 10 unlike a conventional transmission device where it represents the weak point of the device.

[0056] The motion transmission device 10 according to the present application may be manufactured using a manufacturing method comprising the following successive steps: providing a preform of a transmission shaft 20 and providing a transmission element 40 comprising a complementary essentially planar fixing surface 42; arranging the transmission element 40 relative to the preform so as to position the complementary fixing surface 42 opposite a portion of the preform intended to form a fixing section 22; inserting the arrangement of the transmission element 40 and the preform into a mold 100; and injecting a die into the mold 100 to form the transmission shaft 20 comprising a fixing section 22 provided with an essentially planar fixing surface 24 matching the complementary fixing surface 42 of the transmission element 40.

[0057] Alternatively, the motion transmission device 10 according to the present application may be manufactured using a manufacturing method comprising the following successive steps: providing a preform of a transmission shaft 20; inserting the preform into a mold 100; injecting a die into the mold 100 to form the transmission shaft 20 comprising a fixing section 22 provided with an essentially planar fixing surface 24; and fitting a fitting portion 44 of a transmission element 40 so that a complementary fixing surface 42 of the transmission element 40 fits the fixing surface 24 of the transmission shaft 20.

[0058] According to one possibility, the transmission shaft 20 can be manufactured by pultrusion, in particular in the case where the transmission shaft 20 has a constant section over its entire length.

[0059] The manufacturing method may comprise tightening a clamping screw 46 in order to tighten the fitting portion 44 against the fixing section 22. The tightening of the fitting portion 44 against the fixing section 22 may advantageously make use of a deformability of the transmission element 40.

[0060] The manufacturing method may include applying an adhesive 60 between the transmission element 40 and the attachment section 22 to connect the transmission element 40 to the attachment section 22. The application of the adhesive 60 may be performed by injecting the adhesive 60 into the hole 52.

[0061] The mold 100 may comprise two mold parts 110, 120. In the case where the transmission shaft 20 is made of composite material, the transmission shaft 20 may be molded in a female mold 100, polymerized under internal pressure via an inflatable bladder 130. This embodiment makes it possible to guarantee a high quality of the external surface of the transmission shaft 20, which makes it possible to obtain at least one fixing surface 24 necessary for fixing the transmission element 40 with precision.

[0062] The method of manufacturing the motion transmission device 10 according to the present application may comprise a molding method corresponding to the molding method defined by patent application FR3109746A1.

Claims

AMENDED CLAIMS received by the International Bureau on May 23, 2023 (23.05.2023) 1) Motion transmission device for an actuation and / or opening and / or closing and / or locking and / or unlocking mechanism of a mechanical motion control device for a door, flap, right-angle drive or flight control of an aircraft, comprising a transmission shaft (20) extending along a longitudinal axis (A), the transmission shaft (20) having at least one mounting section (22), the motion transmission device (10) further comprising a transmission element (40) fixed to the mounting section (22), said mounting section (22) having a non-circular cross-section in a plane orthogonal to the longitudinal axis (A) and comprising at least one mounting surface (24) while the transmission element (40) has a complementary mounting surface (42) conforming to the mounting surface (24),characterized in that, on the one hand, said transmission shaft (20) is made of a composite material comprising carbon fibers, on the other hand, said transmission element (40) is made of a metallic material, and it comprises a fitting portion (44) fitted onto said fixing section (22) while at least one clamping screw (46) allows the fitting portion (44) to be tightened against the fixing section (22). 2) Transmission device according to claim 1, characterized in that the transmission element (40) is made of aluminium. 3) Transmission device according to any one of claims 1 to 3, characterized in that the fixing surface (24) and the complementary fixing surface (42) are essentially flat and each extend in a plane parallel to the longitudinal axis (A). 4) Transmission device according to any one of claims 1 to 3, characterized in that the fixing section (22) comprises in a plane orthogonal to the longitudinal axis (A) AMENDED SHEET (ARTICLE 19) a cross-section of essentially polygonal shape, preferably in the shape of an equilateral and / or equiangular polygon. 5) Transmission device according to any one of claims 1 to 4, characterized in that the transmission shaft (20) is a tubular element. 6) Transmission device according to any one of claims 1 to 5, characterized in that the transmission element (40) comprises a pin (48) forming a mechanical obstacle to a displacement of the transmission element (40) along the transmission shaft (20) parallel to the longitudinal axis (A). 7) Transmission device according to claim 6 characterized in that the transmission element (40) and / or the transmission shaft (20) each have a hole (50, 26) in which the pin (48) is received, the hole (50) of the transmission element (40) being preferably provided in the fitting part (44) and / or the hole (26) of the transmission shaft (20) being preferably provided in the fixing surface (24). 8) Transmission device according to any one of claims 1 to 7, characterized in that it further comprises an adhesive (60) linking the transmission element (40) to the fixing section (22). 9) Aircraft comprising a motion transmission device (10) according to any one of claims 1 to 8. AMENDED SHEET (ARTICLE 19)

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