WO2024260667A1 - Aircraft door ejector with a valve incorporating a dead stroke and method for assembling such a valve - Google Patents

Abstract

The invention relates to a door ejector (3) which comprises a gas pressure activator, the activator being a valve (30) in connection with a pneumatic actuator. The valve (30) forms an integral assembly comprising a body (3c) through which an axial bore (3a) passes, in which a first rod (T1) is translated by a transmission force exerted along a first distance referred to as dead stroke, and then along a second stroke, referred to as active stroke, in which a second rod (T2) is also driven by coupling with the first rod (T1). The second rod (T2) then opens the gas tank (33) by driving a sealing plug (7), the released gas being channelled along an axial passage of the bore (3a) coupled to an exhaust channel (34) in connection with the pneumatic actuator incorporated in the ejector (3).

Description

DESCRIPTION

AIRCRAFT DOOR EJECTOR WITH VALVE INCORPORATING A DEAD STROKE AND METHOD FOR ASSEMBLING SUCH A VALVE.

TECHNICAL AREA

The invention relates to an aircraft door ejector or any vehicle equipped with a door allowing, in emergency cases, the door to be opened by the pressure of a gas released by a single-block valve incorporating a dead stroke.

In order to open a passenger door or an emergency exit door in a single operation, these doors are generally equipped with an ejector. Such an ejector comprises a pneumatic and/or hydraulic actuator, of the cylinder type, in connection with means for triggering this actuator and means for opening the door. The actuator is thus activated, during an emergency evacuation procedure, by the triggering means in order to obtain an almost immediate opening of the doors without requiring any other intervention.

The triggering means are capable of generating almost instantaneously a high pressure provided by the sudden release of a gas or a hydraulic fluid contained in a tank. The triggering means are of the mechanical type - with a valve or membrane associated with rupture means - of the pyrotechnic or electrical type when the gas triggering is of pyrotechnic or electrical origin. The mechanical triggering means allow a secure triggering of gas and/or hydraulic fluid.

STATE OF THE ART

Patent document FR 2 957 626 discloses an emergency opening ejector for an aircraft opening, comprising a pressurized gas reservoir equipped with a membrane capable of being perforated to release the gas and actuate a cylinder mounted on the opening. The perforator is a pointed rod, movable in translation along an axis perpendicular to the membrane. However, the membranes are fragile and exposed to ruptures due to the conditions of use (temperature variations, microcracks, etc.). For example, the solution of the document cited above provides in the main claim means for escaping the gas not actuating the cylinder via a valve which, according to a predetermined position, then opens access to a dedicated circuit in the event of accidental rupture of the membrane.

In addition, the membrane must be replaced after each use, which generates risks of pollution at the level of the internal circuits. These internal circuits are also polluted in the event of rupture of the membrane.

Valve-type triggering means - flap, gate or valve - are advantageously regulated in order to respond to gas leakage problems due to vibration and thermal expansion phenomena. Regulation makes it possible to precisely control the flow rate at which the fluid circulates between the reservoir and the cylinder.

For example, there is known from patent document US 8225815 a regulator for the circulation of a fluid to maintain the same flow rate in the actuator for a wide temperature range, the regulator and the actuator forming two entities connected by fluid connections. The regulator is a valve comprising two fluid flow zones connected by a passage between the zones, each zone also being in fluid connection with one of the chambers of the actuator via an orifice of variable size. These orifices form alternative flow openings depending on the direction of the differential pressure exerted between the zones of the regulator. A constant flow rate could thus be achieved by flowing a suitable volume allowing regulation of the actuator over a wide temperature range.

Furthermore, patent document FR 3 016 007 uses a sliding valve in a two-cavity valve body to supply gas to a pneumatic cylinder. The valve is mounted on this pneumatic cylinder and a connection connects one of the cavities of the valve to the cylinder to form an ejector. The valve has a passage between the two cavities, this passage being closed by breakable means so that, the valve being movable between two positions, one of the positions closes the passage to the gas when the pressure difference between the two cavities is less than a predetermined value and releases this passage otherwise. This solution would allow to protect the ejector by switching from a standard operating state to an emergency operating state without overpressure.

PRESENTATION OF THE INVENTION

Valve solutions using variable opening orifices via moving elements require a two-part ejector assembly connected by multiple links, which does not guarantee controlled triggering of the gas in the actuator.

In order to overcome this problem, the present invention provides for triggering the supply of gas in a single compact assembly by means of the opening of a gas passage towards the door actuator, the opening being caused by a movable means at the end of a stroke without the pressure being released during this preliminary phase.

More specifically, the present invention relates to a door ejector, in particular an aircraft door, comprising a gas pressure activator contained in a tank, the activator being a valve connected to a pneumatic actuator capable of causing the door to open by the pressure of released gas. In this ejector, the valve forms a single-piece assembly extending along a central axis and comprising a body crossed by an axial bore in which a first rod can move, against a return means, over a first axial distance called the dead travel by the exercise of a transmission force generated by triggering means. In a contact position at the end of the dead travel, the transmission force is capable of also moving a second rod driven by the first rod, the rods having ends previously associated by coupling means, over a second axial travel called the active travel between the contact position and the gas opening position. The second rod is then capable of opening the gas tank by driving a sealing cap of the tank. The released gas is then channeled along at least one axial passage of the bore formed between the second rod and the bore, this passage being connected to at least one exhaust channel in connection with the pneumatic actuator integrated into the ejector. Preferably, the exhaust channel extends transversely to the bore of the two rods.

Under these conditions, the valve contains the gas pressure in the tank without any leakage consequences, and this until the precise moment when the pressure is released, nor does it use a consumable part such as a membrane. Advantageously, no maintenance is required on the triggering means. The dead stroke is easily achieved from a simple coupling of rods, no shimming being necessary to obtain this dead stroke. In addition, obtaining a dead stroke by adjusted guidance of the movable rods in a bore eliminates any risk of blockage.

According to preferred embodiments:

- the coupling means are chosen between an interlacing of the ends of the rods, a nipple connection and a tenon-mortise assembly;

- in the case of an interlacing coupling, each rod has an end tab which fits into a recess of the other rod formed between the end tab of this other rod and a recess bottom, this bottom extending opposite the tab at a distance substantially equal to the dead travel in the waiting position;

- in the case of a coupling by connector, the dead travel D1 is covered by a nipple-shaped end piece formed at the end of the first rod, capable of moving in a cylindrical housing formed in the axial bore of the valve and having at least one hook for holding the end piece in this housing;

- in particular, the cylindrical housing may be formed at the end of the second rod and include a hook formed on an end portion of the cylindrical housing, or the cylindrical housing may be equipped with two half-moon type hooks for holding nipple-shaped end pieces formed at the end of the rods, the end pieces being arranged facing each other in the housing;

- in the case of a mortise and tenon assembly, the first rod has an oblong-shaped end piece extending perpendicular to the axis of the valve and capable of being positioned in a cylindrical housing formed in the second rod after a quarter turn rotation, the rods then being blocked by pins arranged in the valve body perpendicular to the central valve axis;

- the triggering means are chosen from mechanical, electrical and electromagnetic means; the sealing cap is provided with at least one sealing gasket capable of coming to bear on an annular end of the valve body?

The subject of the invention also relates to a method of assembling the monobloc valve of the ejector defined above. This method comprises the following steps:

- alignment of the first rod provided with a return means on the second rod by coupling the ends of the rods arranged opposite each other and separated by a distance representing the dead travel that the first rod can travel;

- fixing the sealing cap to the second end of the second rod, in particular by screwing;

- installation of the valve in the ejector and connection to the valve trigger means by exerting a transmission force.

According to preferred embodiments, the coupling between the rods is achieved by choice of interlacing between the rod ends before the introduction of the aligned rods into the axial bore of the valve body, by nipple connection with the hooking of at least one rod end into the valve bore, and by a mortise-and-tenon type connection between the rod ends.

In the case of a nipple connection, the hooking is carried out with the spring compressed in a compression position going beyond the active stroke, the rods then being positioned so that a larger diameter of the cylindrical bore allows the opening of the hook in order to hook the nipple.

PRESENTATION OF FIGURES Other characteristics and advantages of the present invention will emerge from the following reading of detailed exemplary embodiments without limiting their scope, with reference to the appended figures which represent, respectively:

- Figure 1, a schematic front view of an aircraft door equipped with a door opening ejector;

- figure 2, a front view in partial section of a door opening ejector according to the invention;

- figure 3, a sectional view of an example of a monobloc valve according to the invention;

- figures 4a, 4b, 4c and 4d, the essential steps of assembling the valve according to the previous figure;

- Figures 5a, 5b and 5c, partial enlarged views of said valve during the two successive strokes of the rods after an emergency opening trigger;

- Figures 6a, 6b and 6c, cross-sectional views of other examples of monobloc valves having different means of coupling the stem ends, with enlargements at the level of the couplings for Figures 6a and 6b; and

- Figures 7a to 7d, partial perspective views of the valve example according to Figure 6c during steps of setting up the coupling between the rods by a tenon-mortise assembly.

DETAILED DESCRIPTION

In the figures, identical reference signs refer to the same element and to the corresponding passages of the description.

With reference to FIG. 1 , the aircraft door 1 shown schematically is equipped with an arm 2 for opening/closing the door 1 , this arm 2 comprising an emergency door opening ejector 3 provided with a pneumatic actuator cylinder 4 in connection with a pivoting mechanism 5 for the door 1 (not visible in the figure). This mechanism, which causes the final opening of a door by pressure when an ejector is triggered, is known and is not part of the present invention. The partial sectional front view of FIG. 2 details more precisely the components of the ejector 3, in particular a valve 30 connected at one end to a trigger means 31, here internal rods to the valve 30, as described below. Furthermore, the valve 30 is connected at its other end to a sealing plug 7 mounted in a gas bottle 33. In addition, the valve 30 is connected to the actuator cylinder 4 via a lateral exhaust channel 34 which extends perpendicular to the central axis X'X of the valve 30. Furthermore, a pressure reducer 8 is mounted on the exhaust channel 34 in order to adjust the pressure at the valve outlet to the desired level at the inlet of the cylinder 4.

The cylinder 4 comprises a piston 40 capable of moving in the cylinder between two positions: a position A in which the piston end 41 is waiting and an advanced position B in which this end 41 has triggered an emergency door opening by pressure via the mechanism 5 (see figure 1).

A cross-sectional view of a first example of a monobloc valve 30 is illustrated in FIG. 3. This valve 30 comprises a body 3c crossed by a cylindrical axial bore 3a with a longitudinal axis coincident with the central axis X'X. Two rods are housed in this axial bore 3a. A first rod T1 is engaged on several portions of the bore 3a: an inlet portion P1, in which the rod T1 is centered via a ferrule V1 mounted inside the bore and an O-ring J1; followed by an intermediate portion P2 in which the rod T1 remains adjusted with a section of narrowed diameter to house a spring R1 bearing between a narrowing rim B1 of the rod T1 and a narrowing rim B2 of the valve body 3c; and a main connecting portion P3 in which the rod T1 is coupled to a second rod T2.

In the connecting portion P3 of the bore 3a, the rod T1 is coupled to the rod T2 by the notches 10e, 11e formed at their respective facing ends 10b and 11a, the rods being able to move in an adjusted manner in this portion P3. The rod T2 remains in adjusted movement in the connecting portion P3 between two support shoulders E1 and E2 which free between them a passage 6 along the bore 3a, the axial section of the rod T2 being smaller between the shoulders than that of the bore 3a. In addition, an annular duct C1 is arranged in this portion P3 approximately halfway between the ends of the portion P3. As variants, it is possible to provide several passages and several exhaust ducts for the gas. The sealing cap 7 is screwed onto the second rod T2 at the outlet of the connecting portion P3. To do this, the rod T2 has at its second end 11 b a threaded part 1 B which is screwed onto an internal thread 7i of a blind nut 7e. The blind nut 7e is screwed against a housing 7b of a circular seal J3. This seal comes into sealing support against an annular end 3e of the valve body 3c, while the housing 7b comes into support against a shoulder E3 of the rod T2 via a washer 7r. The washer then serves to hold the sealing seal J3 in position so that it can be driven by the axial movement of the rod T2.

In the example shown, this J3 seal is a rectangular section seal made of molded elastomeric material. Alternatively, this seal can be assembled and can be made of suitable flexible material (silicone, polyurethane foam, etc.).

The valve body 3c is assembled in a housing 3b of the ejector 3 (see FIG. 2) by a thread formed on the valve 30 in connection with a tapping made in the base 3b, resting on an annular rim B3 and O-rings J4 and J5. Such an assembly is described below in detail with reference to the successive steps illustrated by FIGS. 4a to 4d.

In Figure 4a, the first rod T1 provided with the return spring R1 is aligned with the second rod T2 and coupled to it by their ends, second end 10b for the first rod T1 and first end 11a for the second. This coupling is achieved by inserting each tab 10p, 11p of the rod ends 10b, 11a into the notch 10e, 11e formed by the tab of the rod located opposite. The tabs have a disk sector-shaped geometry in this example.

Then the assembly of the two rods T1 and T2 thus intertwined is introduced into the axial bore 3a of the valve body 3c to a waiting position where the spring R1 rests on the narrowing edge B2 of the valve body 3c (figure 4b).

The sealing cap 7 is then screwed (rotation arrow F1) onto the second end 11b of the second rod T2 (figure 4c) until it comes into abutment against the seal housing 7b resting on the washer 7r which is then axially blocked by the shoulder E3 (see figure 3). Then the valve 30 is put in place in the housing 3b of the ejector 3 complementary to its external configuration (figure 4d) so that the annular duct C1 is connected to the exhaust channel 34. The mechanical trigger 31 (see figure 2) connected to the first end 10a of the first rod T1 then exerts a transmission force of appropriate intensity to achieve two strokes: a dead stroke against the return force of the spring R1 and an active stroke against this return force increased by that generated by the pressure contained in the bottle 33. The bottle 33 is initially filled with nitrogen in this example at an appropriate pressure.

The partial enlarged views of the valve 30 of figures 5a to 5c show the waiting position and the end of the two successive strokes of the rods T1, T2 of the valve 30 during an emergency opening trigger, at the coupling between these two rods (figure 5a and figure 5b) and at the connection between the second rod T2 and the plug 7 (figure 5c). In the waiting position (figure 5a), at the instant of triggering, the ends 10b and 11a of the respective rods T1 and T2 are coupled and the same gap D1 is left free between each end tab 10p, 11p of the rods T1 and T2 and the bottom 11f, 10f of the notch 11e, 10e opposite. Advantageously, for reasons of machining tolerance, the distance between the tab 10p of the rod T1 and the bottom 11f of the notch of the rod T2 can remain slightly greater than the distance D1 between the tab 11p of the rod T2 and the bottom of the notch 10f of the notch of the rod T1.

This gap D1 represents the dead travel traveled by the first rod T1 when the trigger 31 (see figure 2) exerts the transmission force Fa in the direction S1 along the axis X’X of the valve 30. The dead travel makes it possible to absorb any leakage at rest, caused in particular by thermal expansion.

At the end of the dead stroke, the legs 10p and 11p are pressed against the bottoms 10f and 11f (figure 5b). Once the dead stroke D1 has been completed, the rod T1 is in contact position against the rod T2 and the valve 30 is in position to release the gas. From this moment (figure 5c), the transmission force Fa drives the two adjoining rods, T1 and T2 in the same direction S1 to follow the same active stroke. The force Fa then causes (figure 5c) the displacement of the sealing plug 7 driven by the rod T2 via the shoulder E3 against the washer 7r.

The stopper 7 is then driven by the rod T2 by the transmission force until it travels a distance D2 of active travel and is pushed in the direction S1 to open access to passage 6 between seal J3 and valve body 3c. The gas then escapes from bottle 33 (see figure 4d) through passage 6 following the arrowed path F2, and exerts pressure on piston 40 (see figure 2) after having expanded in pressure reducer 8 (see figure 2) by engagement in channel 34 via conduit C1, piston 40 passing from position A to position B in dotted lines. Alternatively, several conduits can be used depending on requirements.

Sectional views of other examples of monobloc valves are illustrated with reference to the longitudinal sectional views of Figures 6a to 6c, with different means of coupling the stem ends, Figures 6a and 6b showing enlargements A1 and A2 at the couplings.

The valve 50 of Figure 6a (with its enlargement A1) comprises a first rod T3 having an end piece 5a for coupling with the second rod T4, the end piece 5a having a nipple shape. The dead travel D3 is traveled by the end piece 5a of diameter adapted to move in a cylindrical housing L5 limited by a circular hook 5b formed on an end portion of the second rod T4.

The nipple connection in the housing L5 is carried out with the spring R1 compressed in a compression position going beyond the active stroke, the rods T3 and T4 then being positioned so that the larger diameter of the cylindrical bore 3a allows the hook 5b to open in order to hook the nipple 5a. This assembly makes it possible to guarantee the coupling during the total consumption of the active stroke.

As a variant of the valve 50 (illustrated in figure 6b with its enlargement A2), the valve 50’ comprises two hooks 5k and 5k’, of the half-moon type, housing nipple-shaped end pieces 5a, 5c arranged at the end of the rods thus connected T3 and T5 and arranged opposite each other. The dead travel D4 traveled by the end piece 5a extends between its waiting position against the hooks 5k, 5k’ and its contact position against the end piece 5c. Similarly to the previous example, the upper diameter of the bore 3a allows the nipple 5a to be hooked when the spring R1 is compressed into a position exceeding the active travel.

Referring to Figure 6c, the valve 60 uses a stem T6 with an oblong tip 5d extending perpendicular to the central axis X'X of the valve bore (cf. figure 3). The tip 5d is arranged in a cylindrical housing L6 formed at the end of a second rod T7 according to a tenon-mortise type assembly.

Partial perspective views 7a to 7d break down the essential steps of this coupling between the stems T6 and T7 of the valve 60. The stem T6 is arranged above the stem T7 so that its tip 5d, arranged on the stem body 7c via a cylindrical mandrel 7m, can be inserted between two guide flats M1 and M2 of the stem T7 (figure 7a). After vertical insertion (arrow F3), the tip 5d of the stem T6 reaches the cylindrical housing L6 against the return force of the spring R1 (figure 7b).

A quarter-turn rotation (arrow F4) holds the tip 5d against the upper wall 6s of the housing L6 in the waiting position (figure 7c). The dead distance is represented here by the gap D5 between the end face 5f of the tip 5d and the bottom 6f of the housing L6.

A rotation lock is achieved (figure 7d) by two pins G1 and G2, assembled in the valve body 3c, mounted tightly or by screwing or equivalent, perpendicular to the central axis X’X of the valve body 3c and here perpendicular to each other. The pin G1 allows the stem T6 to be blocked at a flat M3 formed on the stem body 7c, and the pin G2 ensures the stem T7 to be blocked.

The invention is not limited to the embodiments and implementations described and shown. Thus, the active stroke can be operated by a helical movement of the first rod,

Furthermore, the coupling between the two rods can be achieved by any assembly system presenting axial play by the use of clamps, fingers, hooks, teeth, etc. In addition, the cap can be fixed to the second rod by any means (clipping, gluing, etc.) or even constitute a single piece with the second rod.

In addition, the return means can be of any type: elastic blade, ring of elastic material, etc., and the sealing means can be of a shape adapted to the context (annular, crown, cylindrical, etc.).

Claims

1 . Door ejector (3) comprising a gas pressure activator contained in a reservoir (33), the activator being a valve (30, 60) connected to a pneumatic actuator (4) capable of causing the door (1) to open by the pressure of released gas, characterized in that the valve (30, 50, 50', 60) forms a single-piece assembly extending along a central axis (X'X) and comprising a body (3c) traversed by an axial bore (3a) in which a first rod (T1, T3, T6) can move, against a return means (R1), over a first axial distance (D1, D3, D4, D5) called the dead travel by the exercise of a transmission force (Fa) generated by trigger means (31) in that in a contact position at the end of the dead travel the transmission force (Fa) is capable of also moving a second rod (T2, T3, T6) over a second ... third rod (T2, T3, T6) over a second axial distance (D1, D3, D4, D5) called the dead travel by the exercise of a transmission force (Fa) generated by trigger means (31) in that in a contact position at the end of the dead travel the transmission force (Fa T4, T5, T7) driven by the first (T1, T3, T6), the rods having ends (10b, 11a) previously associated by coupling means (10e, 11 p; 11 e,10p; 5a, 5b, 5k, 5k'; 5d, L6), on a second axial stroke (D2) called active stroke between the contact position and a gas opening position (33) by driving a sealing plug (7) of the tank (33), and in that the released gas is then channeled along at least one axial passage (6) of the bore (3a) formed between the second rod (T2, T4, T5, T6) and the bore (3a), this passage (6) being connected to at least one exhaust channel (34) in direct connection with the pneumatic actuator (4) integrated in the ejector (3). 2. Ejector according to claim 1, in which the coupling means are chosen between an end interlacing (10e, 11p; 11e, 10p) of the rods (T1, T2), a nipple connection (5a, 5b, 5k, 5k') and a tenon-mortise assembly (5d, L6). 3. Ejector according to claim 2 in which, in the case of coupling by interlacing, each rod (T1, T2) has an end tab (10p, 11p) which fits into a recess (11e, 10e) of the other rod (T2, T1) formed between the end tab (11p, 10p) of this other rod (T2, T1) and a recess bottom (11f, 10f), this bottom extending opposite the housed leg (10p, 11p) at a distance substantially equal to the dead travel (D1) in the waiting position. 4. Ejector according to claim 2 wherein, in the case of a coupling by connector, the dead travel (D3, D4) is covered by a nipple-shaped end piece (5a) formed at the end of the first rod (T3), capable of moving in a cylindrical housing (L5) formed in the axial bore (3a) of the valve (50, 50') and having at least one hook (5b; 5k, 5k') for holding the end piece (5a) in this housing (L5). 5. An ejector according to claim 4, wherein the cylindrical housing (L5) is formed at the end of the second rod (T4) and comprises a hook (5b) formed on an end portion of the cylindrical housing (L5). 6. Ejector according to claim 4, in which the cylindrical housing (L5) is equipped with two half-moon hooks (5k, 5k') for holding nipple-shaped end pieces (5a, 5c) formed at the end of the rods (T3, T5) and arranged opposite each other in the housing (L5). 7. Ejector according to claim 2 wherein, in the case of a mortise and tenon assembly, the first rod (T6) has an oblong-shaped tip (5d) extending perpendicular to the axis (X'X) of the valve (60) and capable of being positioned in a cylindrical housing (L6) formed in the second rod (T7) after a quarter-turn rotation, the rods being blocked by pins (G1, G2) arranged in the valve body (3c) perpendicular to the central valve axis (X'X). 8. Ejector according to any one of claims 1 to 7, in which the triggering means (31) are chosen from mechanical, electrical and electromagnetic means. 9. Ejector according to any one of claims 1 to 4, in which the plug (7) is provided with at least one seal (J3) capable of coming to bear on an annular end (3e) of the valve body (3c). 10. Method of assembling the monobloc valve of the ejector according to any one of claims 1 to 9, characterized in that it comprises the following steps: - alignment of the first rod (T1, T3, T6) provided with a return means (R1) on the second rod (T3, T4, T5, T7) by coupling the ends (10b, 11a) of the rods arranged opposite; - fixing the sealing cap (7) to the second end (11 b) of the second rod (T2, T4, T5, T6), in particular by screwing; - placing the valve (30) in the ejector (3) and connecting it to the triggering means (31) of the valve (30) by exerting a transmission force (Fa). 11. Assembly method according to claim 10, in which the coupling between the rods (T1, T3, T6; T2, T4, T5, T7) is carried out by choice by interlacing between the rod ends (10b, 11a) before the introduction of the aligned rods into the axial bore (3a) of the valve body (3c), by nipple connection with the hook (5b; 5k, 5k') of at least one rod end (5a, 5c) in the valve bore (3a), and by a tenon-mortise type connection between the rod ends (5d, L6). 12. Assembly method according to claim 11 in which, in the case of a nipple connection, the hooking is carried out with the spring (R1) compressed in a compression position going beyond the active stroke (D2), the rods (T3; T4, T5) then being positioned so that a larger diameter of the cylindrical bore (3a) allows the opening of the hook (5b; 5k, 5k') in order to hook the nipple (5a, 5c).