Pneumatic launch device for a drone

Abstract

The invention relates to a pneumatic launch device (1) for a drone (2), comprising a launch tube (3), a pressurization chamber (6) located at the rear of the tube (3) and provided with a passage opening (63) leading into the tube (3), and means for temporarily closing the passage opening (63). According to the invention, the temporary closing means (7) are arranged to change from a closed configuration to an open configuration instantaneously under the action of the gas pressure inside said chamber (6), after the latter has reached a trigger pressure, and the cross-section of the passage opening (63) is sufficiently large so that instantaneously upon changing to said open configuration, the gas pressure prevailing in the chamber (6) and the space behind the drone (2), then in communication with each other, is the desired launch pressure for the drone (2).Figure to be published with the abbreviation: Figure 1.

Description

Title of the invention: Pneumatic launching device for a drone

[0001] The technical field of the invention is that of pneumatic launching devices, and more specifically, that of pneumatic launching devices for drones.

[0002] Drones can carry a payload intended for civil or military missions, surveillance, intelligence, combat or transport. Drones are small, cheaper and simpler to operate than aircraft carrying a pilot, and are experiencing significant growth.

[0003] Several means of launching drones are known, including pneumatic launching devices.

[0004] A pneumatic launch device is a device that uses compressed air, or any other type of pressurized gas, to cause the drone to launch.

[0005] Conventionally, a pneumatic launch device comprises a pressurization chamber which is pressurized by a compressed gas. The release of the pressure contained in the chamber generates energy, which energy is used to propel the drone.

[0006] There are many types of pneumatic launching devices. In particular, the pressure can be released by various means.

[0007] A known type of pneumatic launching device is a pneumatic catapult drone launcher, such as that disclosed, for example, in French patent application FR2297770 AL. The operating principle of this pneumatic catapult is the expansion of a pressurized gas in a telescopic assembly of two cylindrical and concentric tubes so as to cause the rectilinear movement of one relative to the other.

[0008] Another type of known pneumatic launching device is a launching tube device, such as those disclosed in US patent US7584925 B2 and in international patent application WO2015 / 127178.

[0009] The purpose of these launch tube devices is to propel the drone a few meters above the vehicle carrying the launch tube for deployment of this drone, in order to avoid any contact of the drone with the antennas mounted on the vehicle and to quickly deploy the drone.

[0010] In the launch device according to patent US7584925 B2, during launch a launch gas contained in a launch gas tank is released into a launch tube after opening a valve system, a first portion of this launch gas forces a free sliding piston mounted inside the launch tube to move toward the open front end of the launch tube, and a second portion of the launch gas exits the launch tube through its open front end.

[0011] In the launch device according to patent application WO2015 / 127178, during launch a compressed gas contained in a chamber is released into a launch tube containing the drone after opening a discharge valve.

[0012] The launch tube devices described above have the disadvantage of not allowing sufficient control of the value of the gas pressure by which the drone is ejected, and therefore of not allowing control of the speed and height of the ejection of the drone, so that it is necessary to provide a safety margin before the deployment of the drone in order to prevent it from coming into contact with, for example, the antennas of the vehicle.

[0013] The present invention thus aims to propose a pneumatic launching device making it possible to control the launching pressure by which the drone is ejected, thus capable of ejecting a drone in a reliable and reproducible manner and thanks to which an effectively rapid deployment of the drone can be implemented.

[0014] The solution according to the present invention is based on the use of means making it possible to instantly apply to the drone the pressure by which it is desired that the drone be ejected, and not a progressive, or even partial, release of gas pressure behind the drone as in the devices of the prior state of the art.

[0015] The present invention therefore relates to a device for pneumatically launching a drone, a device comprising: • a longitudinal launch tube having a first, rear end, which is closed and a second, front end, which is open, and the interior of which defines a launch chamber intended to receive a drone and in which is located a seat against which the drone is positioned before its launch; • a pressurization chamber located at the rear end of the launch tube and capable of being pressurized by a pressure source, the pressurization chamber having a first, front end, in which is provided a passage opening opening into the launch chamber and, in use, behind the drone placed against the seat; and • means for temporarily closing the passage opening capable of instantly changing from a closed configuration, in which the passage opening is sealed, to an open configuration in which the passage opening is completely open,

[0016] characterized by the fact that the temporary closure means are arranged to pass from the closed configuration to the open configuration instantaneously under the action of the gas pressure inside the pressurization chamber, after the latter has reached a predetermined pressure, called trigger pressure, and by the fact that the cross-section of the passage opening is large enough so that instantaneously upon passage of the temporary closure means from the closed configuration to the open configuration, the gas pressure prevailing in the pressurization chamber and the space located behind the drone, then in communication with each other, is the desired launch pressure for the drone.

[0017] The expression "fully open" means that the temporary sealing means are clear of the passage opening.

[0018] Advantageously, the cross-section of the passage opening represents between 30% and 50% of the cross-section of the launch chamber.

[0019] It is possible to provide that the temporary closure means are arranged to pass from the closed configuration to the open configuration by actuation of a mechanically actuable release means. For example, the temporary closure means may thus comprise a flap mounted freely pivoting at the outlet of the passage opening, or two flaps mounted freely pivoting about axes arranged on either side of the passage opening, and held in a closed position by a mechanical lock movable between a position locking the flap in the closed position, and a release position in which it is disengaged from the flap which is then caused instantly to pivot and open the passage opening by the gas pressure. The movement of the lock may be controlled by any suitable means, such as for example by electromagnet.In this way, the drone launch instruction is implemented by the lock control.

[0020] According to a preferred embodiment, the temporary sealing means are arranged to switch from the closed configuration to the open configuration automatically as soon as the gas pressure inside the pressurization chamber reaches the trigger pressure.

[0021] The temporary sealing means may then advantageously comprise a rupture disc assembly which is arranged at the passage opening and comprises a calibrated membrane extending across the passage opening so as to seal it, the membrane being sized to rupture at the trigger pressure.

[0022] The calibrated membrane can, for example, be made of stainless steel, plastic or graphite. Of course, it can be made of any other suitable material.

[0023] The tared membrane may be designed to rupture all around its periphery, at level of which is made integral with the pressurization chamber, or to break from its center, or according to any other mode of rupture allowing the passage opening to be completely open.

[0024] The rupture disc assembly may be removably attached to the pressurization chamber. Preferably, the rupture disc assembly comprises a support ring and a fixing ring of the same dimensions and attached to each other by fixing members passing through holes provided for this purpose in the rings, with the periphery of the calibrated membrane sandwiched between the rings, the rupture disc assembly being removably attached to the front end of the pressurization chamber also by said fixing members.

[0025] Such a rupture disc assembly has the advantage of being both low cost and quick to open. When maintaining and reconditioning a new drone, it is simply a matter of replacing the ruptured membrane with a new membrane, which is more economical than replacing, for example, a pyrotechnic initiator and a gas-generating charge.

[0026] The rear end of the launch tube may be formed by a base removably attached to an inner shoulder of the launch tube, from which base extends a tubular part whose longitudinal axis is coaxial with the longitudinal axis of the launch tube and which defines, with the base, the pressurization chamber, a seal being interposed between the tubular part and the inner annular edge of the inner shoulder. The device is then of a simple structure to produce and assemble.

[0027] The front end of the launch tube may be closed by a sealed cap.

[0028] The device according to the present invention may comprise said pressure source, which is formed by an external gas source, arranged outside the launch tube, and connected to the pressurization chamber by a pneumatic connection. Such a remote arrangement of the pressure source allows remote control and also makes it possible to provide a compact device.

[0029] Alternatively, the device according to the present invention comprises said pressure source, which is formed by an internal gas source, arranged inside the launch tube, preferably inside the pressurization chamber. Preferably, the pressure source comprises, placed in the pressurization chamber, a diffuser, delimiting a reservoir of a first reagent, and a second reagent, the first and second reagents, when brought into contact with each other, reacting to generate a gas for pressurizing the pressurization chamber, a solenoid valve being arranged so as to selectively allow the reservoir and the pressurization chamber to be put into fluid communication, and preferably the first reagent is pressurized hydrogen peroxide (H2O2) and the second reagent is a solid catalyst based on potassium permanganate (KmnO4).

[0030] Such a pressure source may be used when an external pressure source is not available.

[0031] The device according to the present invention may further comprise a launch shoe capable of being received in the launch chamber and brought into contact against the seat, the launch shoe being configured to contain and surround the drone before launch and during its movement along the launch tube during ejection. The shoe allows the protection and guidance of the drone in the launch tube during the launch phase, and it also allows the energy developed by the gas pressure to be guided, pressurized and distributed.

[0032] It should therefore be specified here that according to the present invention the drone can be in direct contact against the seat of the launch tube, or in indirect contact with it, via the sabot.

[0033] Advantageously, the launching shoe is formed from several separable segments, preferably four segments.

[0034] To better illustrate the object of the present invention, a particular embodiment thereof will be described below, with reference to the attached drawings. In these drawings:

[0035] [Fig.l] is a side view, in longitudinal section, of the pneumatic launching device according to the particular embodiment of the present invention, with a pressure source according to a first embodiment;

[0036] [Fig.2] is a side view, along a first partial longitudinal sectional plane, of the pneumatic launching device of [Fig.l], with a pressure source according to a second embodiment;

[0037] [Fig.3] is a longitudinal sectional view of the pressure source according to the second embodiment, along a sectional plane perpendicular to said first sectional plane;

[0038] [Fig.4] is an exploded perspective view of the device of [Fig.l], the sabot and the drone being omitted;

[0039] [Fig.5] is an exploded perspective view of the sabot and the drone, in their configuration before launch; and

[0040] [Fig.6] is a perspective view of the sabot and the drone, in their configuration after launch.

[0041] If we first refer to Figures 1, 5 and 6, we can see that the pneumatic launching device 1 according to the present invention is intended for launching a drone-type object 2.

[0042] Such a drone 2 comprises, in a conventional manner, a base body 20 containing a powertrain, a battery pack and navigation electronics. The drone 2 shown in Figures 5 and 6 comprises two counter-rotating rotors 21a, 21b, namely two superimposed propellers. It should be noted that the drone 2 could comprise any number of rotors. The blades 22 of each rotor 21a, 21b are foldable and can therefore be moved from a folded position ([Fig.5]) to a deployed position ([Fig.6]). The drone 2 is equipped with a payload 23 removably mounted on the base body 20. This payload 23 can be a lethal or non-lethal load. For example, the drone 2 could be equipped with a lethal explosive-type load, a non-lethal load for dropping paint or smoke, or an optronic load for observation and detection.

[0043] If we now refer to Figures 1 to 4, we can see that the device 1 comprises a launch tube 3 with a longitudinal axis A1, intended to receive the object to be launched, namely the drone 2, before its launch, and ejection means 4 for ejecting the drone 2.

[0044] The launch tube 3 has a generally cylindrical shape around its longitudinal axis A1, and it has a front end 3a forming the mouth for the exit of the drone 2 and a rear end 3b in the region of which the ejection means 4 are arranged.

[0045] It is emphasized here that the terms “front” and “rear” are understood by reference to the predetermined direction of movement of the drone 2 relative to the launch tube 3 during launch.

[0046] The front end 3a is closed, before launching, by a circular-shaped sealed plug 30 whose diameter corresponds to the external diameter of the launching tube 3. An O-ring 31 is interposed between the plug 30 and the internal wall of the launching tube 3, at the front end 3a.

[0047] The rear end 3b is formed by a base 32 which is in the form of a block of circular section, the diameter of which corresponds to the external diameter of the launch tube 3. The base 32 is fixed to an inner shoulder 33 of the launch tube 3, of annular shape, by fixing members 34, such as screws, passing through orifices provided in the base 32 and orifices provided in the inner shoulder 33 and situated opposite each other.

[0048] The launch tube 3 defines inside thereof a cylindrical launch chamber 35 having, in the region of the rear end 3b, a seat 36, here formed by the internal shoulder 33, against which the drone 2 will be placed before ejection from the launch tube 3 by the ejection means 4.

[0049] The ejection means 4 comprise a pressure source 5 or 5', a pressurization chamber 6 and temporary sealing means 7.

[0050] The pressure source 5 or 5' is intended to allow the pressurization chamber 6 to be pressurized by compressed gas, which may be air, an inert gas, steam, etc., or any combination thereof.

[0051] It should therefore be emphasized that, although the term "pneumatic" is used to designate the launch device according to the present invention, it is not limited to the use of air as the launch gas for the drone 2.

[0052] The pressure source can be any gas pressure source.

[0053] In the embodiment of [Fig.l], for reasons of space requirement, the pressure source 5 is an external pressure source, that is to say it is arranged outside the launch tube 3 and is capable of being placed in communication with the pressurization chamber 6 via a pneumatic connection 50. This pneumatic connection 50 comprises an inlet orifice which opens into the base 32.

[0054] The pressurization chamber 6 is delimited laterally by a tubular part 60, of longitudinal axis A2, extending perpendicularly from the transverse wall of the base 32, in other words parallel to said longitudinal axis A1, in the direction of the front end 3a of the launch tube 3. Thus, the pressurization chamber 6 has a rear end 6b closed by said transverse wall and an open front end 6a, and is located inside the rear region of the launch tube 3. The tubular part 60 is here formed in one piece with the base 32, but alternatively the pressurization chamber 6 can be fixed thereto by any suitable means.

[0055] A gas inlet orifice 61 is provided in a region of the side wall of the pressurization chamber 6 which is located in the base 32, to allow gas entering through an inlet orifice of the base 32 to enter the pressurization chamber 6.

[0056] In the embodiment of Figures 2 and 3, the pressure source is an internal pressure source 5', that is to say arranged inside the launch tube 3, and more particularly, inside the pressurization chamber 6 which is here formed by a pressurization bell 60'.

[0057] The pressure source 5' is a chemical initiator, here based on the reaction between hydrogen peroxide (H2O2) and potassium permanganate (KMnO4).

[0058] The chemical initiator 5' comprises a diffuser 51 delimiting a reservoir 52 of H2O 2, a solenoid valve 53, a solid catalyst 54 based on KMnO4, a piston 55, a spring 56 and a reservoir cap 57.

[0059] The pressurization bell 60' is in the form of a tubular body intended to receive all of the components of the chemical initiator 5' and fixed to the base 32 so as to delimit a chamber similar to that formed by the tubular part 60, namely located at the rear end 3b of the launch tube 3. The longitudinal axis of the bell 60' is thus also coaxial with the longitudinal axis A1 of the launch tube 3.

[0060] The diffuser 51 is formed by a generally cylindrical part, one end of which has an annular flange 51a on which the bell 60' is mounted, with inter position of a seal between the two, and which is made integral with the base 32, in particular by screws, again with the interposition of a seal between the two. The generally cylindrical part comprises, starting from the flange 51a, a rear part 51b in which is formed a cavity opening into the central opening of the flange 51a and receiving the solenoid valve 53, a tubular front part 51c whose front end is closed by the tank cap 57, and an intermediate part 51d separating the rear and front parts 51b, 51c.

[0061] The piston 55 is mounted inside the front part 51c, between the plug 57 and the intermediate part 51d. The spring 56 is a helical spring mounted between the piston 55 and the plug 57, the ends of the spring 56 bearing respectively against the piston 55 and the plug 57. The plug 57 and the piston 55 each having a cavity, said cavities being able to receive the spring 56 when the plug 57 and the piston 55 are in contact with each other. The region delimited laterally by the internal lateral wall of the front part 5le, at the rear by the intermediate part 5Id and at the front by the piston 55 constitutes the reservoir 52 of H2O2 which can be put under pressure by the action of the piston 55 and the spring 56. The front end of the plug 57 is made integral with the front end of the bell 60', the latter itself being made integral, in particular by screwing, with the temporary sealing means 7.

[0062] The solid catalyst 54 based on KMnO4 is received in the space formed between the first part 51b of the diffuser 51 and the internal side wall of the bell 60'. This solid catalyst 54 is therefore in the form of an annular body having a rear wall in contact with the flange 51a.

[0063] As can be better seen in [Fig. 2], first channels 51e are provided in the intermediate part 51d so as to put the reservoir 52 into fluid communication with a free space 5 If in the cavity in which the solenoid valve 53 is received. The first channels 51e are here parallel to the longitudinal axis of the diffuser 51. If we now refer to [Fig. 3], we can see that second oblique channels 51g are also provided in the intermediate part 51d so as to put the pressurization chamber 6 into fluid communication with an outlet passage 5 Ih provided in the center of the intermediate part 5 Id and which can be put into fluid communication with said free space 5 If by actuation of the solenoid valve 53. It is therefore possible to control the solenoid valve 53 so as to cause the contents of the reservoir 52 to enter the pressurization chamber 6 where the solid catalyst 54 is located.

[0064] The exothermic chemical reaction between the solid catalyst 54 based on KMnO4 and the H2O2 contained in the reservoir 52 makes it possible to generate a very large quantity of oxygen and water vapor, allowing the pressurization chamber 6 to be pressurized, up to the trigger pressure.

[0065] The longitudinal axis A2 of the pressurization chamber 6 is coaxial with the axis Ion- gitudinal Al of the launch chamber 35. The outer diameter of the pressurization chamber 6 is smaller than the inner diameter of the launch tube 3, so that a free space is formed between the outer wall of the pressurization chamber 6 and the inner wall of the launch tube 3, allowing part of the object to be ejected to be received there if necessary.

[0066] The pressurization chamber 6, whether defined by the tubular part 60 or the pressurization bell 60', comprises, at its open front end 6a, an annular internal rim 62 which delimits a circular passage opening 63 opening into the launch chamber 35.

[0067] The temporary sealing means 7 are arranged at the passage opening 63 and serve to selectively seal it. More precisely, the temporary sealing means 7 are capable of sealing the passage opening 63, before launch, and of leaving it free at the instant of launch.

[0068] In other words, the temporary closure means 7 are capable of changing instantaneously from a closed configuration to an open configuration. In the closed configuration, the front end 6a is closed, so that the pressurization chamber 6 is sealed and no gas exchange is possible between the pressurization chamber 6 and the launch chamber 35, which are not placed in communication. In the open configuration, the passage opening 63 is not closed, the front end 6a is open, the pressurization chamber 6 and the launch chamber 35 are in communication and the gas contained in the pressurization chamber 6 enters the launch chamber 35 to eject the drone 2.

[0069] In preferred embodiments of the present invention (Figures 1 to 4), the temporary sealing means 7 comprise a rupture disc assembly 70 comprising a calibrated membrane 71.

[0070] The rupture disc 70 comprises a support ring 72 fixed to the front end 6a of the pressurization chamber 6 and carrying the calibrated membrane 71.

[0071] The support ring 72 has a first side, a second side, an outer peripheral edge and an annular inner peripheral edge, the latter delimiting a central opening 72a whose diameter, in other words the inner diameter of the support ring 72, is equal to the diameter of the passage opening 63. The outer diameter of the support ring 72 is equal to the outer diameter of the tubular part 60, where appropriate to the outer diameter of the bell 60'. The first side of the support ring 72 is applied against the inner rim 62 and the second side of the support ring 72 is therefore oriented towards the front end 3a of the launch tube 3. In other words, the support ring 72 is interposed between the front end 6a of the pressurization chamber 6 and the launch chamber 35.

[0072] The calibrated membrane 71 extends across the central opening 72a of the ring of support 72. Thus, in the closed configuration, the calibrated membrane 71 closes the entire passage opening 63.

[0073] Concerning the mode of rupture of the membrane 71, different variants may be suitable, provided that the rupture of the membrane 71 clears the entire section of the passage opening 63. For example, the membrane 71 could rupture at its periphery, namely its junction zone with the support ring 72, or in its center.

[0074] The rupture disc assembly 70 is fixed to the pressurization chamber 6 by a fixing ring 73. The fixing ring 73 is a part similar to the support ring 72 and is in the form of a flat annular section of the same dimensions as the support ring 72. A first side of the fixing ring 73 is applied against the second side of the support ring 72. Holes, capable of receiving fixing members 74, are provided in the fixing ring 73, so as to come opposite corresponding holes provided in the support ring 72 and in the internal rim 62. Thus, the rupture disc assembly 70 is fixed to the open end 6a of the pressurization chamber 6 by fixing members 74 passing through the fixing ring 73, the membrane 71, the support ring 72 and the internal rim 62, and the heads of which are located on the pressurization chamber side. launch 35.In the assembled state of the rupture disc assembly 70, it is therefore interposed between the internal rim 62 and the fixing ring 73. Such an assembly is easy and allows the rupture disc assembly 70 and the membrane 71 to be easily and quickly dismantled, after rupture, in order to replace it with another rupture disc carrying an unruptured membrane, or to replace only the membrane.

[0075] Referring again to Figures 1, 2, 5 and 6, it can be seen that the device 1 further comprises a launching shoe 8 intended to receive the drone 2.

[0076] The launch shoe 8 is sized and configured to be received in the launch chamber 35 to allow the drone 2 to be guided in the launch tube 3 during the launch phase, and to surround a drone 2 to allow the drone 2 to be protected during launch. It should be emphasized that a different shoe 8 is defined according to the profile of the drone 2 and its payload 23.

[0077] In the particular embodiment shown, the sabot 8 is formed of several separable segments 80, in particular four segments 80. These segments 80 delimit between them a space 81 for receiving the drone having an opening intended to be located opposite the front end 3a of the launch tube 3. These segments 80 also delimit between them a space 82 for receiving the pressurization chamber 6, having an opening intended to allow the passage of the pressurization chamber 6 when the sabot 8 is introduced into the launch chamber 35.

[0078] The segments 80 may be identical.

[0079] Alternatively, the sabot 8 could be formed of four separable segments, including three identical segments and one segment containing a device 9 for recharging and communication between the drone 2 and the launch tube 3. The sabot 8 being intended to be ejected from the launch tube 3 and to separate from the drone 2 after launch, the recharging and communication device 9 is a wireless device. Preferably, this device 9 is of the inductive type and comprises a transmission coil capable of cooperating with a receiving coil housed in the drone 2. This device 9 further comprises spring contacts 90 capable of cooperating with a contact plate provided in the launch tube 3 for the connection between this device 9 and the launch tube 3.

[0080] The device 1 allows the launching of drones by controlling the launching pressure by which the drone 2 is ejected, and therefore a reliable and reproducible ejection for rapid deployment of the drone 2.

[0081] This is possible thanks to the fact that: - on the one hand, the membrane 71 is calibrated to open by breaking when the pressure applied to it by the gas present in the pressurization chamber 6 reaches a predetermined value, which will be the so-called trigger pressure, the rupture disc assembly 70 then instantly passing into its open configuration, and - on the other hand, the cross-section of the passage opening 63 is large enough so that immediately after the rupture of the membrane 71, the pressure prevailing in the volume composed of the pressurization chamber 6 and the free space of the launch chamber 35 located between the pressurization chamber 6 and the drone 2 (namely here the reception space 82 formed by the shoe 8), is the desired launch pressure for the drone 2.

[0082] Indeed, at the very moment of rupture of the calibrated membrane 71, the compressed gas will instantly occupy all the free volume at its disposal.

[0083] Therefore, depending on characteristics of the launch tube, such as its inner diameter and length, and of the drone, such as its weight, speed and height at which it must be ejected before it can be safely deployed, the launch pressure can be defined in advance, namely the gas pressure that should be applied to it when it is in position against the seat 36 taking into account the volume of the pressurization chamber 6 and the volume of said free space, and thus the trigger pressure, namely the gas pressure in the pressurization chamber 6 which will make it possible to obtain the launch pressure after rupture of the calibrated membrane 71.

[0084] Thus, when one wishes to launch a drone 2, one first introduces the launching shoe 8, in the receiving space 81 from which the drone 2 is received, by the end front 3a open of the launch tube 3, until it comes into contact with the seat 36, then the front end 3a of the launch tube 3 is closed by the watertight cap 30.

[0085] When it is desired to launch the drone 2, the pressure source 5 or 5' is placed in communication with the pressurization chamber 6 or actuated to pressurize the pressurization chamber 6 to the desired trigger pressure. As soon as the trigger pressure is reached, the membrane 71 ruptures, thus opening the passage opening 63. The compressed gas that was until then in the pressurization chamber 6 is released and instantly occupies the receiving space 82 of the sabot 8 and applies a thrust force against its face, ejecting the sabot 8 and the drone 2 from the launch tube 3, at the same time ejecting the sealed plug 30. Once ejected from the launch tube 3, the sabot 8 separates into separate segments 80 due to the friction of the air and the thrust exerted by the blades 22 of the drone 2 when they pass into the deployed position.Once at its peak, drone 2 starts, stabilizes and its mission can begin.

[0086] In the case where it is desired to implement the launching of a plurality of drones 2, a plurality of launching devices 1 according to the present invention can be mounted on the same vehicle (not shown). In this case, and in the case where the pressure source is an external pressure source, a single pneumatic circuit is necessary to pressurize the pressurization chambers 6. In this variant, each launching tube 3 can bear a color code depending on the payload 23 with which the drone 2 is equipped. This allows visual and rapid identification of the object to be ejected.

[0087] It is understood that the particular embodiments which have just been described have been given for informational and non-limiting purposes, and that modifications may be made without departing from the scope of the present invention.

Claims

Claims

1. Device (1) for pneumatically launching a drone (2), device (1) comprising: • a longitudinal launch tube (3) having a first end (3b), rear, which is closed and a second end (3a), front, which is open, and the interior of which defines a launch chamber (35) intended to receive a drone (2) and in which is located a seat (36) against which the drone (2) is positioned before its launch; • a pressurization chamber (6) located at the rear end (3b) of the launch tube (3) and capable of being pressurized by a pressure source (5'), the pressurization chamber (6) having a first end (6a), front, in which is provided a passage opening (63) opening into the launch chamber (35) and, in use, behind the drone (2) placed against the seat (36); and • means (7) for temporarily closing the passage opening (63) capable of instantly switching from a closed configuration, in which the passage opening (63) is sealed, to an open configuration in which the passage opening (63) is completely open, the temporary sealing means (7) being arranged to pass from the closed configuration to the open configuration instantaneously under the action of the gas pressure inside the pressurization chamber (6), after the latter has reached a predetermined pressure, called triggering, and by the fact that the cross-section of the passage opening (63) is sufficiently large to that instantly upon passing the temporary closure means (7) from the closed configuration to the open configuration, the gas pressure prevailing in the pressurization chamber (6) and the space behind the drone (2), then in communication with each other, is the desired launch pressure for the drone (2), characterized in that it comprises said pressure source (5'), which is formed by an internal gas source arranged inside of the pressurization chamber (6), said pressure source (5') comprising, placed in the pressurization chamber (6), a diffuser (51), delimiting a reservoir (52) of a first reagent, and a second reagent (54), the first and second reagents, when brought into contact with each other, reacting by generating a gas for pressurizing the pressurization chamber (6), a solenoid valve (53) being arranged so as to selectively allow the reservoir (52) and the pressurization chamber (6) to be put into fluid communication.

2. Device (1) according to claim 1, characterized in that the cross-section of the passage opening (63) represents between 30% and 50% of the cross-section of the launch chamber (35).

3. Device (1) according to any one of claims 1 and 2, characterized in that the temporary sealing means (7) are arranged to pass from the closed configuration to the open configuration automatically as soon as the gas pressure inside the pressurization chamber (6) reaches the trigger pressure.

4. Device (1) according to claim 3, characterized in that the temporary sealing means (7) comprise a rupture disc assembly (70) which is arranged at the passage opening (63) and comprises a calibrated membrane (71) extending across the passage opening (63) so as to seal it, the membrane (71) being sized to rupture at the trigger pressure.

5. Device (1) according to claim 4, characterized in that the rupture disc assembly (70) is removably attached to the pressurization chamber (6).

6. Device (1) according to claim 5, characterized in that the rupture disc assembly (70) comprises a support ring (72) and a fixing ring (73) of the same dimensions and fixed to each other by fixing members (74) passing through holes provided for this purpose in the rings (72, 73), with the periphery of the calibrated membrane (71) sandwiched between the rings (72, 73), the rupture disc assembly being removably fixed to the front end (6a) of the pressurization chamber (6) also by said fixing members (74).

7. Device (1) according to any one of claims 1 to 6, characterized in that the rear end (3b) of the launch tube (3) is formed by a base (32) removably fixed to an inner shoulder (33) of the launch tube (3), base (32) from which extends a tubular part (60, 60') whose longitudinal axis (A2) is coaxial with the longitudinal axis (Al) of the launch tube (1) and which defines, with the base (32), the pressurization chamber (6), a seal (31) being interposed between the tubular part (60, 60') and the inner annular edge of the inner shoulder (33).

8. Device (1) according to any one of claims 1 to 7, characterized in that the first reagent is hydrogen peroxide (H2O2) under pressure and the second reagent (54) is a solid catalyst based on potassium permanganate (KmnO4).

9. Device (1) according to any one of claims 1 to 8, characterized in that it further comprises a launch shoe (8) capable of being received in the launch chamber (35) and brought into contact against the seat (36), the launch shoe (8) being configured to contain and surround the drone (2) before launch and during its movement along the launch tube (3) during ejection.

10. Device (1) according to claim 9, characterized in that the launching shoe (8) is formed from several separable segments (80), preferably four segments.

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