Device for emergency opening of an aircraft door with circumferential retaining element

Description

TECHNICAL FIELD

[0001] The invention relates to the field of aeronautics and more particularly relates to a device for emergency opening of an aircraft door.

[0002] Aircraft doors may be opened to allow access to the cabin or cargo compartments, or to allow evacuation in an emergency. In the event of an emergency evacuation of passengers, aircraft doors, whether passenger doors or emergency evacuation doors, usually have an emergency opening device which, if activated, causes a rapid opening without significant effort, regardless of the possible position of the aircraft at the time of evacuation. It is imperative that the activation of the emergency opening device requires only a small amount of effort. PRIOR ART

[0003] Currently, as described in particular in patent application FR2830564, the actuating means conventionally consist of a pneumatic actuator powered by means of an additional reserve of working fluid. Such actuating means, however, have several drawbacks. Indeed, they have a relatively significant weight and size, due in particular to the presence of the additional reserve of working fluid. In addition, they require periodic monitoring of the pressure of the working fluid, and periodic maintenance or replacement of the additional reserve even when the latter is not in use. Finally, after activation of the emergency opening device, these actuating means require, in order to be operational again, a reconditioning of the additional reserve of working fluid.

[0004] Another current solution described in particular in patent application FR2864021 makes it possible to reduce the size and weight of the actuation means. Indeed, according to this solution, the actuation means consist of a pyrotechnic cylinder, i.e. an autonomous cylinder not requiring a source of supply of driving fluid. On the other hand, such pyrotechnic cylinders need to be periodically inspected and replaced even when not in use. These pyrotechnic cylinders must, in addition, also be reconditioned after activation of the emergency opening device. This obviously poses the problem of transporting and storing explosive elements.

[0005] Patent application FR2975967 describes an aircraft emergency opening device that overcomes the drawbacks described above. This emergency opening device consists of mechanically designed actuation means that eliminate the need for pneumatic or pyrotechnic elements. The weight and size of the emergency opening device are thus reduced, reliability is increased, and this device requires little or no maintenance. However, the described emergency opening device remains complex and bulky. In addition, the addition of control means for the emergency opening device increases the overall size of the device.

[0006] Document WO2020 / 020861 also describes an aircraft emergency opening device whose operation and control are entirely mechanical, this control requiring little effort from the user. However, this opening device is limited in its use because it does not allow the movement of the door to be controlled. STATEMENT OF THE INVENTION

[0007] The aim of the invention is to improve the emergency opening devices of the prior art.

[0008] To this end, the invention relates to a device for emergency opening of an aircraft door, comprising: a tubular actuating member extending in an axial direction, provided with a first connecting end and a second connecting end, this tubular actuating member being switchable between a retracted rest position and a deployed open position; elastic compression means adapted to bias the tubular actuating member from its retracted position to its deployed position; a member for retaining the tubular actuating member in its retracted position with the elastic compression means kept compressed; triggering means adapted to release the retaining member and cause the tubular actuating member to move to its deployed position under the effect of the expansion of the elastic compression means.

[0009] In this emergency opening device: the tubular actuating member comprises a first end plate, located on the side of the first connecting end, and a second end plate, located on the side of the second connecting end; the elastic compression means comprise a tubular spring compressed between the first end plate and the second end plate; an expansion regulator is arranged inside the tubular spring; the retaining member comprises at least one peripheral attachment connecting the first end plate to the second end plate, this peripheral attachment being radially external to the tubular spring.

[0010] Such an emergency opening device has all the advantages of a mechanical device as described in document FR2975967. The actuating means have reduced weight and size. The mechanical design of the actuating means does not require any particular maintenance when the opening device is not in use. No driving fluid is necessary to activate the actuating means.

[0011] The invention also aims at an extremely compact arrangement of the emergency opening device which includes all of the mechanical elements producing the opening movement, the triggering elements, and the elements allowing the opening to be controlled.

[0012] The emergency opening device can thus be sized to provide a significant opening force which leads to rapid opening of the aircraft door, for example by relying on damping the movement of the door along the opening stroke thanks to the expansion regulator which is integrated within the emergency opening device, or by controlling the opening and closing of the door while the tubular actuating member is in the retracted position.

[0013] The triggering elements can also be entirely mechanical, which leads to a fully mechanical emergency opening device that does not require any connection to an external power source or remote control. Such a device forms a finished product of the autonomous mechanical cylinder type, which is a guarantee of reliability and operational safety that is appreciable in the field of aeronautics and more particularly emergency opening devices.

[0014] In the emergency opening device according to the invention, the retention of the actuating member does not rely on any mobile mechanism whose parts would require complex means to remain mobile under load (bearings, rings, etc.) and would be subject to wear by friction, matting, and other disadvantages relating to mobile mechanical parts maintained under heavy loads.

[0015] The invention allows a drastic simplification of the emergency opening devices of the prior art by eliminating numerous mechanical parts, which makes the device lighter, more compact and more reliable, in addition to lowering its cost.

[0016] The emergency opening device according to the invention may include the following additional features, alone or in combination: the retaining member comprises a plurality of peripheral fasteners radially external to the tubular spring, each of these peripheral fasteners comprising a retaining rod; each of the retaining rods: extends between an opening made in the first end plate and an opening made in the second end plate; and comprises at one of its ends a fixed head, the triggering means comprising a disengageable head at the other end of the retaining rod; the peripheral fastener comprises a retaining wire; the retaining wire travels at least one way back and forth between the first end plate and the second end plate; the triggering means comprise a disengageable head fixing one end of the retaining wire relative to an orifice in one of the end plates; the triggering means comprise a member for transversely cutting the retaining wire;the first end plate comprises an internal guide cylinder extending in the axial direction and the second end plate comprises an external guide cylinder extending in the axial direction, the internal guide cylinder and the external guide cylinder being concentric and fitted into each other in a sliding connection; the expansion regulator comprises a cylinder chamber delimited by the internal guide cylinder; the expansion regulator comprises a piston movable in the cylinder chamber, in the axial direction; the piston is connected by a connecting rod to the second connecting end, the connecting rod passing through: a bottom wall of the internal guide cylinder; and the second end plate; the connecting rod comprises a stop for driving the connecting rod by the second end plate; the stop is arranged on a portion of the connecting rod which is located between the second end plate and the second connecting end. ;

[0017] The device according to the invention may comprise elastic means with a high calibration, i.e. intended to exert a significant opening force on the door opening mechanism, which is necessary in this emergency door opening application. Despite the high calibration of the elastic elements, the activation of the actuating means is effortless. In its embodiment with retaining wire, the retaining wire allows a significant decoupling between the force allowing the calibration of the elastic means to be maintained, and the force necessary to trigger the device. Even with elastic means of high calibration involving high tension of the wire, its transverse cutting will require minimal force. The ratio of retaining force to triggering force is very favorable and the invention allows an increase in the calibration of the elastic means while reducing the triggering force. PRESENTATION OF FIGURES

[0018] Other characteristics and advantages of the invention will emerge from the non-limiting description which follows, with reference to the appended drawings in which: [ Fig.1 ] There figure 1 is a schematic sectional view of an emergency opening device according to a first embodiment of the invention; [ Fig.2 ] There figure 2 is a schematic sectional view of an emergency device according to a second embodiment of the invention; [ Fig.3 ] There figure 3 is a schematic sectional view of an emergency opening device according to a third embodiment of the invention; [ Fig.4 ] There figure 4 represents the cutting knife of the device of the figure 3 ; [ Fig.5 ] There figure 5 represents an emergency opening device in an intermediate opening position. DETAILED DESCRIPTION

[0019] There figure 1 illustrates a first embodiment of the invention. This figure 1 is a schematic diagram schematically representing the main elements of an aircraft door emergency opening device in a longitudinal section.

[0020] The emergency opening device is a compact element in the form of a jack which comprises a first connecting end 1 and a second connecting end 2.

[0021] The emergency opening device is intended for mounting in an aircraft door, such that a separation movement of the two connecting ends 1, 2 causes the aircraft door to open. For example, the emergency opening device may be mounted such that the first connecting end 1 and the second connecting end 2 are connected to elements of the door allowing it to open by expansion. According to another example, the two connecting ends may be fixed within the door opening mechanism itself, between two levers whose separation causes the aircraft door to open.

[0022] The first connecting end 1 comprises a pivot 3 allowing a pivot connection of axis 4 with the aircraft door. Similarly, the second connecting end 2 comprises a pivot 5 allowing a pivot connection of axis 6 with the aircraft door.

[0023] The emergency opening device comprises a tubular actuating member 7 which is switchable between a retracted rest position (that of the figure 1 ) and a deployed opening position corresponding to a maximum spacing of the connecting ends 1, 2. During normal operation of the aircraft, the emergency opening device is constantly in its configuration where the tubular actuating member is in its retracted rest position. It is only during an exceptional situation requiring emergency opening of the aircraft door that the emergency opening device is triggered and the tubular actuating member moves from its retracted position to its deployed position.

[0024] The tubular actuating member 7 comprises: a first end plate 8 on which the first connecting end 1 is fixed; a second end plate 9 located on the side of the second connecting end 2.

[0025] The plates extend along a radial plane perpendicular to the axial direction, but are not necessarily flat over their entire surface.

[0026] The emergency opening device further comprises elastic compression means which here comprise a tubular spring 10 which is compressed between the two end plates 8, 9. When the tubular actuating member 7 is in its retracted position, the spring 10 is in the maximum compression position and stores the elastic potential energy necessary for the emergency opening of the aircraft door. This elastic potential energy corresponds to the energy necessary to very quickly open an aircraft door whose weight can potentially be of the order of a hundred kilos, and results in a dimensioning of the compression spring accordingly.

[0027] The tubular nature of the spring 10 is to be interpreted in the broad sense: the spring 10 may be cylindrical or conical, for example. It may be constituted by any means such as a helical spring, or by a stack of elastic washers.

[0028] According to this first embodiment, the emergency opening device comprises a member for retaining the tubular actuating member 7 in its retracted position, which makes it possible to maintain the spring 10 in the compressed position. This retaining member here comprises at least two retaining rods 11 each comprising a fixed head 12 resting on the periphery of an orifice in the second end plate 9 receiving the retaining rod 11.

[0029] The emergency opening device further comprises triggering means adapted to release this retaining member to cause the tubular actuating member 7 to move to its deployed position under the effect of the expansion of the elastic compression means, i.e. the relaxation of the spring 10. These triggering means comprise a disengageable head 13 mounted on the end of each retaining rod 11, at their end opposite the fixed head 12. Like the fixed heads 12, each disengageable head 13 rests on the periphery of an orifice in the first end plate 8 receiving the retaining rod 11.

[0030] The retention rods 11 may, for example, be steel rods sized for the tensile strength necessary to maintain the compression of the spring 10, between the fixed heads 12 in abutment on the second end plate 9 and the disengageable heads 13 in abutment on the first end plate 8.

[0031] The disengageable heads 13 can be produced by any means (mechanical, electromechanical, hydraulic, pyrotechnic, for example), allowing the disengageable head 13 to be detached on command from the corresponding retention rod 11.

[0032] Thus, when a user wishes to trigger the emergency opening device, he controls the disengagement of the disengageable heads 13 which separate from their respective retention rods 11, which releases the retention member and allows the tubular actuating member to move to its deployed position.

[0033] According to a preferred example, the retention rods 11 may be threaded rods and the disengageable heads 13 may consist of an expanding nut. Expanding nuts are known electromechanical devices which comprise an actuator cooperating with an articulated nut adapted to open by an electrical command so that the grip of the nut on the threaded rod is immediately released and the nut becomes slidable on the retention rod 11 when it is triggered.

[0034] The schematic view of the figure 1 represents as an example two retention rods 11. However, the retaining member may comprise as many of these retention rods 11 as necessary, in particular in view of the force of the spring to be contained, angularly distributed around the spring 10.

[0035] In this embodiment, the emergency opening device is preferably triggered by simultaneously triggering the triggering means, i.e. by simultaneously disengaging all the disengageable heads 13.

[0036] The retention rods 11 extend along the axial direction 32 of the emergency opening device. The retention rods 11 here constitute peripheral attachments of the retention member, these peripheral attachments being arranged in a position radially external to the spring 10.

[0037] The tubular actuating member 7 benefits from linear guidance along the axial direction 32, allowing its telescopic character, thanks to: an internal guide cylinder 14 fixed on the first end plate 8 and extending in the axial direction 32; an external guide cylinder 15 fixed on the second end plate 9 and also extending in the axial direction 32, coaxially with the internal guide cylinder 14.

[0038] The two guide cylinders 14, 15 are nested together to provide a sliding connection for the movement of the end plates 8, 9 apart or towards each other. In this simple example, the guide cylinders 14, 15 are adjusted according to a sliding fit. The guide cylinders 14, 15 may, alternatively, comprise any other element constituting a sliding connection such as low friction rings, rollers, etc. The guide cylinders 14, 15 may also be cylinders with a circular base, or any other suitable basic shape.

[0039] The significant amount of elastic potential energy contained in the emergency opening device in the retracted position makes this efficient linear guidance of the tubular actuating member imperative when the spring 10 is released.

[0040] The emergency opening device further comprises an expansion regulator 16 which is here arranged inside the spring 10. The expansion regulator 16 is intended to control the movement of the aircraft door and can perform different functions, independently or in combination.

[0041] For example, the expansion regulator 16 can be used to control the emergency opening movement of the aircraft door. For example, over one range of the opening stroke, the door will have to reach the maximum opening speed permitted by the energy supplied to it by the spring 10, while over other opening ranges, the door will have to reduce its speed. The expansion regulator 16 can in particular greatly reduce the opening speed at the start of the opening stroke to facilitate the opening of the slide and at the end of the opening stroke to avoid damage that could be caused by the door encountering end-of-stroke stops at full speed.

[0042] Another possible function for the expansion regulator 16 is to control the opening and closing movements of the door during its normal use, outside of emergency opening phases. The aircraft door thus does not require a disengaging device, since the opening and closing of the door are possible while the emergency opening device is held in its retracted position. The movement away from or towards the two connecting ends 1, 2 is permitted by the expansion regulator which can also exert a variable resistance to the movement of the door.

[0043] The expansion regulator 16 can also have the function of motorizing the movement of the door, in the case of automatic doors. The expansion regulator 16 is then controlled like a cylinder with the supply of a pressurized fluid allowing automatic opening and closing of the door, while maintaining the emergency opening device in the retracted position.

[0044] The architecture of the emergency opening device described here implements this expansion regulator 16 in a central position (as close as possible to the axial direction 32), with a linear guide (the guide cylinders 14, 15) arranged radially at the periphery of the expansion regulator 16, the linear guide and the expansion regulator 16 being nested. The spring 10 is also arranged radially at the periphery of the linear guide, and the retention and triggering means are finally arranged radially at the periphery of the spring 10.

[0045] This particularly compact architecture integrates all the combined functions of an emergency opening device and an expansion regulator, in the form of a single cylinder-type component, easy and quick to install during aircraft production, and to change during maintenance.

[0046] The expansion regulator 16 here comprises: a cylinder chamber 17 which is delimited by the internal guide cylinder 14, by the first end plate 8 and by a bottom wall 20; a piston 18 movable in the chamber 17 in the axial direction 32.

[0047] The piston 18 is connected by a connecting rod 19 (fixed or articulated) to the second connecting end 2. The connecting rod 19 passes through the bottom wall 20 via a sliding joint, and passes through the second end plate 9. A stop 21 is further provided on the connecting rod 19 between the second end plate 9 and the second connecting end 2. The opening and closing movements of the aircraft door are thus permitted, or even controlled or motorized, by the movement of the piston 18 in the chamber 17, while the emergency opening device is maintained in its retracted position (see figure 5 and its description further on). When the emergency opening device is triggered, the spring 10 causes the two end plates 8, 9 (guided by the guide cylinders 14, 15) to move apart, the second end plate 9 driving in its movement the stop 21 and therefore the second connecting end 2, which causes the emergency opening of the door.

[0048] The chamber 17 can be associated if necessary with fluid conduits (not shown) opening on either side of the piston 18, as well as with hydraulic means of control, protection and thermal compensation.

[0049] There figure 2 is a schematic view similar to the figure 1 , illustrating a second embodiment of the emergency opening device.

[0050] The elements common to the different embodiments bear the same reference numbers in the figures.

[0051] According to this second embodiment, the retaining member here comprises a single peripheral attachment consisting of a retaining wire 22.

[0052] The retaining wire 22 consists of any wire element, or group of wire elements, adapted to work in traction to ensure the retention of the actuating member in the retracted position. The retaining wire may consist of one or more strands, braided or non-braided, of metal wire, textile wire, or even composite material, or non-textile fiber.

[0053] The retaining wire 22 comprises a first end 23 fixed in this example to the first connecting end 1 by any suitable means (screwing, tightening, crimping, etc.), and a second end 24 attached to the triggering means which are constituted here by a disengageable head 13. Between these two ends, the retaining wire 22 makes at least one round trip between the two end plates 8, 9. The retaining wire 22 passes through the first end plate 8 a first time to the second end plate 9 which it passes through, it then comprises a loop 25 extending radially against the second end plate 9 to then pass through the second end plate 9 again in the direction of the first end plate 8 which it passes through again to reach the disengageable head 13.

[0054] The emergency opening device is triggered in the same way as in the first embodiment, by disengaging the disengageable head 13 so that the retaining wire 22 is released and can slide in the various openings that it passes through within the end plates 8, 9, so that the spring 10 is no longer contained, which makes it possible for the tubular actuating member to move to its deployed position.

[0055] There figure 3 illustrates an embodiment of the invention which is entirely mechanical, without any use of power or control cables.

[0056] According to this third embodiment, the retaining member comprises a peripheral attachment which is constituted by a retaining wire 26 arranged at the radial periphery of the spring 10 in a similar manner to the retaining wire of the second embodiment. The retaining wire 26 comprises a first head 27 which immobilizes it in an orifice of the first end plate 8 and comprises a second head 28 which immobilizes it in another orifice of the first end plate 8.

[0057] The retaining wire 26 is here a breakable wire and the triggering means comprise a member for transversely cutting the retaining wire 26. This cutting member may comprise any means suitable for cutting the retaining wire, such as a rotating or translated knife, or scissors. In the example illustrated, the cutting member is a cutting knife 29 movable in translation on two inserts 30, and secured by a pin 31.

[0058] Preferably, the retaining wire is designed, in its structure as in the choice of its material, to have a high tensile strength while having a low resistance to a transverse cutting operation, which is the case for example of a certain number of ropes. In a particularly advantageous embodiment, the retaining wire 22 is made of a bundle of carbon or aramid fibers which have the advantage of having very high tensile breaking values ​​while having a low resistance to transverse cutting.The spring 10 may be provided with a very high calibration, capable of quickly setting in motion, during an emergency opening operation, a massive aircraft door (such as the door of a long-haul aircraft, which are increasingly complex and increasingly heavy, in addition to their substantial size), while maintaining or even reducing the force necessary to trigger the emergency opening device.

[0059] There figure 4 is a front view of the cutting knife 29 showing the upper cutting part and the two oblong holes 33 allowing its translational movement.

[0060] When a user wishes to trigger the emergency opening system, he removes the pin 31 then actuates the cutting knife 29 in translation, which causes the retaining wire 26 to be cut and the spring 10 to be released, then the actuating member 7 to move to its deployed position.

[0061] For the figures 3 And 4 , the two-dimensional schematic view shows the stop 21 in proximity to the retaining wire 22, 26, it being understood that, in a practical embodiment, care will be taken to ensure that the path of the retaining wire 22, 26 does not interfere with the work of the stop 21.

[0062] There figure 5 illustrates the service opening function of the emergency opening device. As part of this function, the emergency opening device is adapted to occupy intermediate positions allowing the door to be opened during normal operation, without the emergency opening device being triggered.

[0063] There figure 5illustrates an emergency opening device according to the invention, which may be in accordance with any of the preceding embodiments. The illustrated device comprises peripheral fasteners 11, 22 which may be pull rods and / or retaining wires on which trigger means as described above act.

[0064] According to this service opening function, the device is not triggered (the tubular actuating member 7 being maintained in its retracted position) while hydraulic control means allow, or even activate, the movement of the piston 18 in the chamber 17. In this configuration, the aircraft door is free to be opened or closed, benefiting from the action of the expansion regulator 16, without interfering with the emergency opening function. It is only when the emergency opening device is triggered that the tubular actuating member will take control thanks to the stop 21, and force the assembly towards the deployed opening position.

[0065] Alternative embodiments of the embodiments described herein may be contemplated. For example, the paths of passage of the retaining wires of embodiments 2 and 3 may be different from those described herein and may include other loops provided that the release of the retaining wire allows the release of the spring 10.

[0066] Furthermore, the fasteners of the different embodiments can be combined. For example, the emergency opening device of the second embodiment can be supplemented by a sectioning member like that of the third embodiment, to combine a controlled triggering possibility with a manual triggering possibility. For example again, the peripheral fasteners can be arranged as in the first embodiment, but be made up of different retaining wires, with one or more suitable sectioning members.

Claims

1. A device for emergency opening of an aircraft door comprising: - a tubular actuating member ( 7 ) extending along an axial direction ( 32 ), provided with a first connecting end ( 1 ) and a second connecting end ( 2 ), the tubular actuating member ( 7 ) being switchable between a retracted rest position and a deployed opening position, the tubular actuating member ( 7 ) comprising a first end plate ( 8 ), situated towards the first connecting end ( 1 ), and a second end plate ( 9 ), situated towards the second connecting end ( 2 ); - an elastic compression device to attract the tubular actuating member ( 7 ) from the retracted rest position to the deployed opening position, the elastic compression device comprising a tubular spring ( 10 ) compressed between the first end plate ( 8 ) and the second end plate ( 9); - a retaining member for retaining the tubular actuating member in the retracted rest position with compression of the elastic compression device maintained; - a triggering device to liberate the retaining member and to cause the tubular actuating member to pass to the deployed opening position due to an expansion effect of the elastic compression device; the device for emergency opening being characterized in that: - an expansion regulator ( 16 ), intended to control the movement of the aircraft door, is arranged inside the tubular spring ( 10 ); - the retaining member comprises at least one peripheral attachment connecting the first end plate ( 8 ) to the second end plate ( 9 ), the peripheral attachment being radially arranged outside at the periphery of the tubular spring ( 10).

2. The device as claimed in claim 1, wherein the retaining member comprises a plurality of peripheral attachments radially outside the tubular spring ( 10 ), each one of the peripheral attachments comprising a retaining bar ( 11 ).

3. The device as claimed in claim 2, wherein each one of the retaining bars ( 11 ) extends between an opening made in the first end plate ( 8 ) and an opening made in the second end plate ( 9 ) and comprises at one end a fixed head ( 12 ), the triggering device comprising a disengageable head ( 13 ) at the other end of the retaining bar ( 11).

4. The device as claimed in claim 1, wherein the peripheral attachment comprises a retaining wire ( 22 , 26 ).

5. The device as claimed in claim 4, wherein the retaining wire ( 22 , 26 ) makes at least one return travel between the first end plate ( 8 ) and the second end plate ( 9 ).

6. The device as claimed in claim 4 or 5, wherein the triggering device comprises a disengageable head (13) fixing one end of the retaining wire ( 22 ) with respect to an orifice of one of the end plates.

7. The device as claimed in any one of claim 4 to 6, wherein the triggering device comprise a transverse member ( 29 ) for transversally severing the retaining wire ( 26 ).

8. The device as claimed in any one of the preceding claims, characterized in that the first end plate ( 8 ) comprises an inner guiding cylinder ( 14 ) extending along the axial direction ( 32 ) and that the second end plate ( 9 ) comprises an outer guiding cylinder ( 15 ) extending in the axial direction ( 32 ), the inner guiding cylinder ( 14 ) and the outer guiding cylinder ( 15 ) being concentric and slotted together along a sliding link.

9. The device as claimed in claim 8, wherein the expansion regulator ( 16 ) comprises a jack chamber ( 17 ) delimited by the inner guiding cylinder ( 14 ).

10. The device as claimed in claim 9, wherein the expansion regulator ( 16 ) comprises a mobile piston ( 18 ) in the jack chamber ( 17 ), oriented along the axial direction ( 32 ).

11. The device as claimed in claim 10, wherein the piston ( 18 ) is connected by a rod ( 19 ) to the second connecting end ( 2 ), the rod ( 19 ) passing through a bottom wall ( 20 ) of the inner guiding cylinder ( 14 ) and through the second end plate ( 9 ).

12. The device as claimed in claim 11, wherein the rod ( 19 ) comprises a stop ( 21 ) for driving the rod ( 19 ) through the second end plate ( 9 ).

13. The device as claimed in claim 12, wherein the stop ( 21 ) is arranged a the portion of the rod ( 19 ) that is situated between the second end plate ( 9 ) and the second connecting end ( 2 ).