DEVICE FOR LAUNCHING A DRONE BY MEANS OF SPRING PROP, METHOD FOR LAUNCHING DRONES WITH THIS DEVICE AND TOOL FOR IMPLEMENTING THIS METHOD

Description

[0001] The technical field of the invention is that of drone launch devices, and more specifically, that of spring-loaded push-type drone launch devices.

[0002] Drones, or remotely piloted aircraft, can carry payloads for civilian or military missions, including surveillance, intelligence gathering, combat, and transport. Smaller in size, less expensive, and simpler to operate than manned aircraft, drones are experiencing significant growth.

[0003] Several drone launch methods are known, including launch tube devices.

[0004] The purpose of these launch tube systems is to propel the drone a few meters above the vehicle carrying the launch tube for deployment. This prevents any contact between the drone and the vehicle's antennas, allowing for rapid deployment.

[0005] There are many types of launch tube systems, including spring-driven systems in which a compression spring presses against the rear end of a launch tube and pushes against a sliding ejection element mounted within the tube. The drone is positioned against this element. The system is armed by compressing the compression spring and locking the ejection element into position, thus activating the armed position. Unlocking is controlled by a release mechanism, which releases the spring and launches the drone, propelled by the ejection element.

[0006] One such launching device is disclosed in Chinese patent application CN111572801 A, where the release mechanism is a rotary mechanism driven by a motor. Similarly, spring compression after drone launch is achieved by a motor integrated into the device and located within the launch tube. A similar prior art example is disclosed in document CN103091069 A.

[0007] However, the use of such motorized means increases the cost and weight of the launch device, and does not allow for optimal compactness, particularly because they limit the volume that can accommodate a drone in the launch tube.

[0008] Therefore, the aim of the invention is to provide a launching device that does not have these drawbacks.

[0009] The solution according to the present invention is based on the use of a detent mechanism comprising at least one detent element whose movement leads to the unlocking of the ejection element and is obtained by the action of a gas pressure in a detent chamber, which notably reduces the costs and weight of the device, and on the use of a separate tool, not integrated into the launch tube, to place the device in the armed position, which increases the volume available for the drone in the launch tube.

[0010] The present invention therefore relates to a device for launching a drone by spring thrust, a device comprising a longitudinal launch tube having a first, rear end, which is closed and a second, front end, which is open, and whose interior defines a launch chamber intended to receive a drone, and means for ejecting the drone from the launch tube which include: an ejection assembly comprising an ejection element, mounted to slide longitudinally in the launch chamber and intended to push the drone to eject it from the launch tube, and a compression spring, called an ejection spring, having a longitudinal axis coaxial with the longitudinal axis of the launch tube and having a first end bearing against the rear end of the launch tube and a second end bearing against the ejection element, the ejection assembly being capable of being placed in an armed position, in which the ejection spring is compressed by the ejection element, locking means for releasingably locking the ejection assembly in the armed position, the locking means comprising at least one retaining element connected to the launch tube and movable between a locking position,in which at least one retaining element is engaged with the ejection element so as to maintain the ejection assembly in the armed position, against the action of the ejection spring, and an unlocking position, in which at least one retaining element is disengaged from the ejection element, and control means for controlling the unlocking of the ejection assembly, by moving at least one retaining element from the locked position to the unlocked position, , characterized by the fact that the control means include: a pressure relief housing, located at the rear of the launch tube and containing a pressure relief chamber suitable for connection to a gas pressure source, at least one pressure relief element which, together with the pressure relief housing, delimits the pressure relief chamber and is movable, under the action of a gas pressure introduced into the pressure relief chamber, from a rest position, in which at least one pressure relief element allows at least one retaining element to remain in the locking position, to a release position, in which at least one pressure relief element has moved at least one retaining element from the locking position to the unlocking position, and means for returning at least one pressure relief element to the rest position.

[0011] These return means can be elastic means, such as a spring.

[0012] Preferably, the control means are configured so that at least one trigger element moves at least one retaining element from the locked position to the unlocked position by translational movement of at least one trigger element. In a particular embodiment, the trigger housing is in the form of a hollow cylinder that is integral with the launch tube and has a longitudinal axis, and the trigger element is a trigger piston mounted in the trigger housing in a sliding manner about said longitudinal axis, the trigger chamber being cylindrical in shape and delimited radially by the trigger housing and axially on one side by the trigger housing and on the other side by the trigger piston.

[0013] However, the present invention is not limited to the way in which at least one detent element moves.

[0014] One could thus provide a pressure relief element that is rotatable relative to the pressure relief housing, around the longitudinal axis of the housing. Such a pressure relief element could, for example, include a paddle-shaped portion received within the pressure relief housing and forming a wall of the pressure chamber, such that the entry of gas into the pressure chamber causes the pressure relief element to rotate. The return means could, for example, consist of a torsion spring extending around a vertical bearing on which the pressure relief element is rotatable, one arm of which is fixed and the other arm of which is integral with the paddle-shaped portion. Stops could be provided by the pressure relief housing to define the rest position and an end-of-travel position for the pressure relief element.At least one retaining element shall be configured to be moved from the locked position to the unlocked position by the rotation of the release element. For example, each retaining element is pivotally mounted in a manner analogous to the embodiment described below, and the release element shall include, extending out of the release housing, for each retaining element, a cam-type member dimensioned to press against the respective retaining element when the release element is rotated.

[0015] To further improve the compactness of the ejection means, advantageously the trigger housing is surrounded by the ejection spring, at least one retaining element is connected to the trigger housing and is located in the internal space of the ejection spring, and the ejection element comprises a thrust head which is perpendicular to the longitudinal axis of the launch tube and against which the second end of the ejection spring presses, and at least one retaining member which is integral with the thrust head and extends into the internal space of the ejection spring, at least one retaining element being configured to hold the ejection assembly in the armed position by grasping at least one retaining member in the locked position.

[0016] Thus, according to a particular advantageous embodiment of the ejection assembly, in which the trigger element is a translationally movable trigger piston, the trigger housing has a first axial, rear side, which is closed, and a second axial, front side, which is open and on which is removably mounted a plug comprising a through bore which is coaxial with the longitudinal axis of the launch tube, the trigger chamber being axially delimited by said first axial side of the trigger housing and by a first closed axial side of the trigger piston, which is in the form of a hollow cylinder whose second axial, front side is open and formed by an annular end, and whose cylindrical wall, which defines an internal space, slides against the cylindrical wall of the trigger housing between the rest position, in which the trigger piston is supported by its first axial side against a shoulder of the trigger housing,and the release position, in which the release piston is supported against an axial stop carried by the plug, at least one retaining element being carried by the plug and, in the cocked position, at least one retaining member extending into the release housing through the through bore of the plug so as to be able to be grasped by at least one retaining element in the locked position, at least one retaining element being configured to be located, in the locked position, on the path followed by the annular end of the release piston during its movement from the rest position to the release position, so as to be moved from the locked position to the unlocked position by pushing the annular end of the release piston against at least one retaining element.

[0017] Preferably, the device comprises a plate which is located in the interior space defined by the cylindrical wall of the expansion piston and is fixed to the plug, and at a distance from it, by spacers, the plate thus having a first face opposite the first axial side of the expansion piston and a second, opposite face, on the side of which is located at least one retaining element, the axial stop being carried by the first face of the plate and the means of returning the expansion piston to the rest position being elastic return means, such as a compression spring, bearing on the first face of the plate and pressing against the first axial side of the expansion piston.

[0018] The present invention is not limited to the manner in which at least one retaining element moves between the locked and unlocked positions. It could thus be envisaged that each retaining element moves in translation.

[0019] Preferably, at least one retaining element is movable between the locking position and the unlocking position by pivoting.

[0020] Preferably, the device comprises two retaining elements each mounted pivoting about a respective pivot axis which is integral with said cap, each pivot axis belongs to a plane perpendicular to the longitudinal axis of the launching tube and is perpendicular to a longitudinal plane of the launching tube, the device further comprising elastic return means for the retaining elements to the locking position.

[0021] The retaining element may be in the form of a rod with a circumferential groove suitable for receiving one end of each retaining element in the locked position.

[0022] The present invention also relates to a method for launching drones using a spring-loaded push-start device as defined above, characterized in that it comprises the following successive steps: a positioning step, comprising positioning a drone in the launch chamber, the ejection assembly being locked in the armed position; a drone launch step, comprising introducing into the expansion chamber sufficient gas pressure to move the expansion element from the rest position to the expansion position, whereby the ejection assembly is unlocked and ejects the drone out of the launch tube; and before the repetition of the positioning step, a repositioning step, comprising returning the ejection assembly to the armed position, in which it is locked by at least one retaining element.

[0023] The present invention also relates to a tool for implementing the method as defined above, characterized in that it comprises a carriage movable in translation along at least one chassis which has, at one end, a drive plate, the carriage and the chassis being able to be introduced into the launching chamber, after the launching step, such that the carriage is in contact with the ejection element and the drive plate is in contact with the open end of the launching tube, with means provided for driving the carriage in translation along the chassis, by which the carriage is movable towards the rear end of the launching tube so as to compress the ejection spring and return the ejection assembly to the armed position.

[0024] Preferably, the chassis further comprises a base plate suitable, in use, to bear against the rear end of the launching tube, and at least one guide rod connecting the base plate and the drive plate and along which the carriage is mounted movable in translation, the means of driving in translation comprising a worm screw and means of driving the rotation of the worm screw, the worm screw extending between the base plate and the drive plate, to which it is connected so as to be able to rotate about its longitudinal axis, and passing through a tapped hole in the carriage, whereby a rotation of the worm screw causes a translation of the carriage.

[0025] The means of rotational drive can be manual or motorized.

[0026] The means of rotational drive may include a gear train mounted in the drive plate and connected to a drive shaft accessible from the outside, for manual drive e.g. by a crank or motorized drive e.g. by means of a drill.

[0027] To better illustrate the object of the present invention, a particular embodiment thereof will be described below, with reference to the accompanying drawings. These drawings show: [ Fig.1 ] is a side view, in longitudinal section, of the launching device according to the particular embodiment of the present invention, in the armed position; [ Fig.2 ] is a side view, in longitudinal section, showing more specifically the ejection means of the device of the [ Fig.1 ], according to a cutting plane perpendicular to the cutting plane of the [ Fig.1 ] ; ] Fig.3 ] is a perspective view of the locking mechanisms in the armed position; [ Fig.4 ] is an exploded perspective view of the locking mechanisms of the [ Fig.3 ] ; ] Fig.5 ] is a perspective view of the tool according to the particular embodiment of the present invention; [ Fig.6 ] is a perspective view of the tool of the [ Fig.5 ], mounted in the launch chamber of the device according to the invention, the launch tube being omitted; and [ Fig.7 ] is a side view, in longitudinal section, of the tool and launching device in the same position as that shown on the [ Fig.6 ].

[0028] If we refer first to the [ Fig.1 ], we can see that the launching device 1 according to the present invention is intended for launching a drone-type object 2.

[0029] Such a drone 2 typically comprises a basic body 20 containing a propulsion unit, a battery pack, and navigation electronics. The drone 2 is equipped with a payload 21 removably mounted on the basic body 20. This payload 21 can be lethal or non-lethal. For example, the drone 2 could be equipped with a lethal explosive charge, a non-lethal charge capable of releasing paint or smoke, or an optronic payload for observation and detection.

[0030] If we now refer to Figures 1 à 4 , we can see that the device 1 includes a launch tube 3 with longitudinal axis A1, intended to receive the object to be launched, namely the drone 2, before its launch, and ejection means 4 to eject the drone 2.

[0031] The launch tube 3 has a general 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.

[0032] It is emphasized here that the terms "front" and "back" are understood by reference to the predetermined direction of movement of the drone 2 relative to the launch tube 3 during launch.

[0033] The front end 3a is closed, before launch, by a circular sealed plug 30 whose diameter corresponds to the outside diameter of the launch tube 3.

[0034] The rear end 3b is closed by a base 31 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 31 is fixed to an internal shoulder 32 of the launch tube 3, of annular shape, by fixing members 33, such as screws, passing through holes provided in the base 31 and holes provided in the internal shoulder 32 and situated opposite each other.

[0035] The launch tube 3 defines within it a cylindrical launch chamber 34 having, in the region of the rear end 3b, a seat 35, here formed by the inner shoulder 32, against which the drone 2 will be placed before ejection out of the launch tube 3 by the ejection means 4.

[0036] The ejection means 4 include an ejection assembly 5 suitable for being placed in an armed position, locking means 6 for releasably locking the ejection assembly 5 in the armed position and control means 7 for controlling the unlocking of the ejection assembly 5.

[0037] As can be seen on the Figures 1 et 2 , the ejection assembly 5 includes an ejection element 50 and an ejection spring 51 which consists of a compression spring.

[0038] In this particular embodiment, the ejection element 50 is in the form of an ejection piston 52 having a piston body 53, a thrust head 54 and a retaining rod 55.

[0039] The piston body 53 is a hollow cylindrical body having a first axial side 53a, directed towards the rear end 3b of the launch tube 3, which is open, and a second axial side, directed towards the front end 3a of the launch tube 3, which is closed by a circular transverse wall 53b having an orifice in its center. A central annular projection 53c surrounding the orifice extends inside the ejector piston 52 from the transverse wall 53b. The transverse wall 53b also has an external annular projection 53d arranged and dimensioned such that the ejection spring 51 is received between the external projection 53d and the internal lateral wall of the piston body 53.

[0040] The thrust head 54 is a hemispherical body integral with the transverse wall 53b, on the outer side of the piston body 53. The diameter of the base of this hemispherical body is equal to the outer diameter of the piston body 53. The thrust head 54 has, in its center, an orifice 54a arranged opposite the orifice of the transverse wall 53b and sized to receive and lock the retaining rod 55, which is thus made integral with the ejection piston 52.

[0041] The retaining rod 55 extends along a longitudinal axis A2 coaxial with the longitudinal axis A1 and extends slidably in a cylindrical bore 56 formed in a plug 57.

[0042] This plug 57 extends transversely to the launching chamber 35, inside the piston body 53. The plug 57 is fixed relative to the launching tube 3. In particular, the plug 57 is fixed, by means of radial screws 58, to an open front side of a tubular housing 37, or sleeve, extending from the base 31.

[0043] The housing 37 extends perpendicularly from the transverse wall of the base 31, in other words parallel to said longitudinal axis A1, in the direction of the front end 3a of the launch tube 3. Preferably, the housing 37 is formed in one piece with the base 31.

[0044] The housing 37 is dimensioned so that it is contained inside the piston body 53 in the armed position of the ejection assembly 5.

[0045] The retaining rod 55 has, at its free end region opposite its end region connected to the piston body 53, a groove 55a for receiving the locking means 6 in the locked position. The groove 55a is formed around the entire circumference of the retaining rod 55.

[0046] The ejection spring 51 is located in the space formed between the outer wall of the housing 37 and the inner wall of the piston body 53, between the rear end 3b of the launch tube 3 and the transverse wall 53b of the piston body 53. More precisely, the ejection spring 51 has a first end bearing against the transverse wall of the base 31 and a second end bearing against the transverse wall 53b, made fixed to these for example by any suitable means.

[0047] The locking means 6 keep the ejection spring 51 in the compressed state, and thus prevent the ejection piston 52 from sliding towards the front end of the launch tube 3, thereby keeping the ejection assembly 5 in the armed position.

[0048] In the particular embodiment shown in the Figures 1 à 4 , the locking means 6 comprise two retaining elements 60.

[0049] Each retaining element 60 is rotatably mounted around a pivot axis 61 fixed to the plug 56. The two pivot axes 61 are parallel to each other. Each pivot axis 61 is fixed to two opposing plates 59 extending perpendicularly from the transverse wall of the plug 56. Thus, the pivot axes 61 are orthogonal to the longitudinal axis A1.

[0050] Each retaining element 60 is in the form of a finger having an angled section 60a and a beak section 60b. The pivot pin 61 is received in a through hole 60c formed at the angle of the angled section 60a. The free end of the angled section 60a has a rounded profile. The beak section 60b has a substantially V-shaped profile. Each retaining element 60 is dimensioned and arranged such that the free end of the beak section 60b is suitable for receiving in the groove 55a of the retaining rod 55, and that the free end region of the angled section 60a is suitable for contacting the inner wall of the housing 37.

[0051] The two retaining elements 60 are arranged in the same plane passing through the longitudinal axis A1 and perpendicular to the transverse wall of the cap 57, with the free ends of their spout sections 60b directed towards each other. Two return springs 62 extend between the two retaining elements 60. In particular, two axes 60d extend on either side of each retaining element 60 at the angle of the spout section 60b and parallel to the pivot axes 61. A return spring 62 is mounted between each opposite axis 60d. These return springs 62 tend to return the spout sections 60b of the retaining elements 60 towards the groove 55a of the retaining rod 55, thus forcing the retaining elements 60 towards their locking position.

[0052] The control means 7 are intended to control the movement of the retaining elements 60 towards their unlocking position, against the return springs 62, by the action of a gas pressure.

[0053] The control means 7 include a pressure-reducing element 70 and a pressure-reducing chamber 71 suitable for connection to a gas pressure source 72.

[0054] The detent element 70 is in the form of a detent piston 73 mounted to slide in the housing 37. As can be seen on the Figures 3 et 4 , the expansion piston 73 is a hollow cylindrical body having a first axial side, directed towards the rear end 3b of the launch tube 3, which is closed by a circular transverse wall 73a, and a second axial side, directed towards the front end 3a of the launch tube 3, which is open and formed by an annular end 73c.

[0055] The housing 37 has a shoulder 37a which defines a first axial stop for the expansion piston 73, against which the transverse wall 73a is in contact when the expansion piston 73 is in the rest position.

[0056] The transverse wall 73a has, in its center, a projecting tubular part forming a counter-stop 73c adapted to come into contact with an axial stop 57a integral with the plug 57 in order to limit the stroke of the expansion piston 73, namely its sliding towards the front end of the housing 37. The axial stop 57a is integral with a transverse circular plate 57b, itself integral, by means of two spacers 57c, with the transverse wall of the plug 57. The two spacers 57c extend on the outside of the plates 59 carrying the articulation axes 61 of the retaining elements 60 and their length is such that the retaining elements 60 cannot come into contact with the plate 57b.

[0057] A compression spring 74 extends around the axial stop 57a and the counter-stop 73c, between the plate 57b and the transverse wall 73a of the expansion piston 73. This spring 74 is designed to force the expansion piston 73 towards the rear end 3b of the launch tube 3, that is, opposite the axial stop 57b. Thus, once the expansion chamber 71 is no longer pressurized, the expansion piston 73 is automatically returned to its rest position, namely to a position in which the expansion piston 73 is not in contact with the retaining elements 60.

[0058] The expansion chamber 71 is radially delimited by the inner wall of the housing 37. The expansion chamber 71 has a rear end closed by the transverse wall of the base 31 and a front end delimited by the transverse wall 73a of the expansion piston 73. The base 31 has an inlet orifice opening into the expansion chamber 71 and intended to be connected to a gas pressure source 72 by a pneumatic fitting 72a.

[0059] The gas pressure source 72 is designed to pressurize the expansion chamber 71 with compressed gas, which may be air. The pressure source 72 can be any type of gas pressure source. For space reasons, the pressure source 72 is an external pressure source, meaning it is located outside the launch tube 3 and is designed to be connected to the expansion chamber 71 via the pneumatic fitting 72a.

[0060] If we refer again to the [ Fig.1 ], we can see that device 1 also includes a launching shoe 8 intended to receive drone 2.

[0061] The launch pad 8 is sized and configured to fit into the launch chamber 34 to guide the drone 2 through the launch tube 3 during the launch phase, and to surround the drone 2 to protect it during launch. It should be noted that a different launch pad 8 is defined depending on the profile of the drone 2 and its payload 21.

[0062] In the particular embodiment shown, the skid 8 is formed of several separable segments 80, for example four identical segments 80. These segments 80 delimit between themselves a drone reception space 2 having an opening intended to be located opposite the front end 3a of the launch tube 3. These segments 80 also delimit between themselves a reception space for the ejection means 4, having an opening intended to allow the passage of the ejection means 4 when the skid 8 is inserted into the launch chamber 34.

[0063] Alternatively, the boot can be formed of four separable segments, three of which are identical, and one segment containing a charging and communication device between the drone and the launch tube. Since the boot is intended to be ejected from the launch tube and detach from the drone after launch, the charging and communication device is wireless. Preferably, this device is inductive and has a transmitting coil B ([ Fig.2 ]) is integral with the base 31 and capable of cooperating, through said device, with a receiving coil housed in the drone.

[0064] The launch device 1 according to the present invention allows the launch of drones 2 in an easy, fast and reliable manner, the launch process comprising a pre-launch phase, a launch phase and a post-launch phase.

[0065] During the pre-launch phase, the launch shoe 8, in the receiving space of which the drone 2 is received, is first introduced through the open front end 3a of the launch tube 3, until it is placed in contact with the seat 35, then the front end 3a of the launch tube 3 is closed by the watertight cap 30.

[0066] During this phase, the ejection means 4 are placed in the receiving space of the ejection means of the shoe 8. In particular, the ejection assembly 5 is in the armed position, the ejection spring 51 is compressed, the retaining elements 60 are in the locking position and the release piston 73 is not in contact with the retaining elements 60.

[0067] When launching the drone 2, during the launch phase, it is sufficient to pressurize the expansion chamber 71. The pressure contained in the expansion chamber 71 will then push the expansion piston 73 towards the retaining elements 60, until the counter-stop 73c of the expansion piston 73 comes into contact with the axial stop 57a. During this sliding movement, the annular end 73b of the expansion piston 73 comes into contact with the rounded profile end of the retaining elements 60 and pushes them inwards, causing the retaining elements 60 to rotate in a direction tending to move the beak sections 60b away from the groove 54a. Once the retaining elements 60 are disengaged from the retaining rod 55, and therefore in the unlocked position, the retaining rod 55 is released and the ejection piston 52 is free to slide and no longer holds the ejection spring 51 in the compressed state.The ejection spring 51 is therefore released instantly and its release causes the ejection piston 52 to slide suddenly towards the front end 3a of the launch tube 3. In this position, the thrust head 53 applies a thrust force against the shoe 8, thus ejecting the shoe 8 and the drone 2 it contains out of the launch tube 3.

[0068] Once ejected from the launch tube 3, the sabot 8 separates into 80 distinct segments. Once at its apogee, the drone 2 starts up, stabilizes, and its mission can begin.

[0069] As can be seen on the [ Fig.7 When the sabot 8 and the drone 2 are ejected from the launch tube 3, the ejection piston 50 is located near the front end 3a of the launch tube 3, with the ejection spring 51 in its fully extended state. Following the venting of the expansion chamber 71, the expansion piston 73 is returned to its rest position by the spring 73, allowing the return springs 62 to pivot the retaining elements 60 inwards.

[0070] During the post-launch phase, it is necessary to prepare the launch device 1 for the launch of another drone 2, in other words, to reposition the ejection assembly 5 in its armed position, during which the ejection spring 51 is compressed again.

[0071] This phase is implemented by tool 9 according to a particular embodiment of the present invention, shown in the Figures 5 à 7 .

[0072] As can be seen on the [ Fig.5 ], the tool 9 comprises a carriage 10 and a chassis 11 along which the carriage 10 is movable in translation by means of translational drive means.

[0073] The translational drive means include a worm screw 12 and a gear train 13.

[0074] The worm screw 12 is mounted between a base plate 14 and a drive plate 15 which are linked together by two guide rods 16 which are part of the frame 11.

[0075] The base plate 14 is a circular plate whose external diameter is less than the internal diameter of the launch tube 3. The base plate 14 has a central cylindrical bore 14a whose diameter is greater than the external diameter of the ejection piston 52.

[0076] The drive plate 15 is also a circular plate suitable for fitting onto the open front end 3a of the launch tube 3, therefore of the same dimensions as the sealing cap 30.

[0077] The drive plate 15 incorporates the gear train 13, one of whose gears is in contact with the thread of the worm gear 12, so that the control of the gear train 13 allows the worm gear 12 to be driven in rotation.

[0078] The carriage 10 is traversed by the two guide rods 16, passing through two bores in the carriage 10, and by the worm screw 12, passing through a tapped hole, such that a rotation of the worm screw 12 causes a translational movement of the carriage 10 along the guide rods 16.

[0079] The carriage 10 has an outside diameter equal to the diameter of the base plate 14. The carriage 10 includes a receiving part, suitable for receiving and enclosing the push head 54 and the front end region of the piston body 53.

[0080] In practice, as can be seen on the [ Fig.7During the post-launch phase, the tool 9 is positioned in the launch tube 3. More specifically, the base plate 14 is positioned against the seat 35, with its bore 14a surrounding the ejection spring 51, the drive plate 15 is positioned at the front end 3a of the launch tube 3, and the carriage 10 is fitted over the thrust head 54. The gear train 13 is driven, either manually or by motor, to rotate the worm gear 12. The carriage 10 is then moved translationally towards the rear end 3b of the launch tube 3. With the carriage 10 fitted over the thrust head 54, the movement of the carriage 10 causes the progressive movement of the thrust head 54, and therefore of the retaining rod 55, towards the rear end 3b, thus compressing the ejection spring 51.When the retaining rod 55 comes into contact with the retaining elements 60, the retaining rod 55 first rotates them against the return springs 62, then the retaining elements 60 automatically engage in the groove 55a as soon as the nozzle sections 60b are aligned with it. The ejection spring 51 is then placed in its compressed state and the ejection assembly 5 is in its cocked position, ready for a new launch phase.

[0081] Tool 9 is removed from launch tube 3 and a new shoe 8 can then be positioned in launch chamber 35, and the previous phases repeated for launching this drone 2 and other drones.

[0082] It is understood that the particular embodiment just described has been given by way of example and not limitation, and that modifications may be made without departing from the scope of the present invention, as claimed.

Claims

1. - A device (1) for launching a drone (2) using spring thrust, the device (1) comprising a longitudinal launch tube (3) having a first rear end (3b), which is closed, and a second front end (3a), which is open, and the inside of which defines a launch chamber (34) intended to receive a drone (2), and means (4) for ejecting the drone (2) from the launch tube (3) which comprise: - an ejection assembly (5) comprising an ejection element (50), mounted so as to slide longitudinally in the launch chamber (34) and intended to push the drone (2) in order to eject it from the launch tube (3), and a compression spring, referred to as an ejection spring (51), having a longitudinal axis coaxial with the longitudinal axis (A1) of the launch tube (3) and a first end of which bears on the rear end (3b) of the launch tube (3) and a second end of which bears against the ejection element (50), the ejection assembly (5) being able to be placed in an armed position, in which the ejection spring (51) is compressed by the ejection element (50), - locking means (6) for releasably locking the ejection assembly (5) in the armed position, the locking means (6) comprising at least one retaining element (60) connected to the launch tube (3) and movable between a locking position, in which the at least one retaining element (60) is engaged with the ejection element (50) so as to hold the ejection assembly (5) in the armed position, against the action of the ejection spring (51), and an unlocking position, in which the at least one retaining element (60) is disengaged from the ejection element (50), and - control means (7) for controlling unlocking of the ejection assembly (5), by moving the at least one retaining element (60) from the locking position to the unlocking position, characterized in that the control means (7) comprise: - a release housing (37), located at the rear of the launch tube (3) and containing a release chamber (71) able to be connected to a gas pressure source (72), - at least one release element (70) which, together with the release housing (37), delimits the release chamber (71) and is movable, under the action of a gas pressure introduced into the release chamber (71), from a rest position in which the at least one release element (70) allows the at least one retaining element (60) to remain in the locking position, to a release position, in which the at least one release element (70) moved the at least one retaining element (60) from the locking position to the unlocking position, and - means (74) for returning the at least one release element (70) to the rest position.

2. - The device (1) according to claim 1, characterized in that the release housing (37) is formed as a hollow cylinder that is integral with the launch tube (3) and has a longitudinal axis, and the release element (70) is a release piston (73) mounted in the release housing (37) so as to slide along said longitudinal axis, the release chamber (71) being cylindrical in shape and delimited radially by the release housing (37) and axially on one side by the release housing (37) and on the other side by the release piston (73).

3. - The device (1) according to any one of claims 1 and 2, characterized in that the release housing (37) is surrounded by the ejection spring (51), the at least one retaining element (60) is connected to the release housing (37) and is located in the interior space of the ejection spring (51), and the ejection element (50) comprises a thrust head (54) that is perpendicular to the longitudinal axis (A1) of the launch tube (3) and against which the second end of the ejection spring (51) bears, and at least one holding member (55) that is integral with the thrust head (54) and extends into the interior space of the ejection spring (51), the at least one retaining element (60) being configured to hold the ejection assembly (5) in the armed position by gripping the at least one holding member (55) in the locking position.

4. - The device (1) according to claim 3, when depending on claim 2, characterized in that the release housing (37) has a first rear axial side, which is closed, and a second front axial side, which is open and on which is removably mounted a plug (57) comprising a through bore (56) that is coaxial with the longitudinal axis (A1) of the launch tube (3), the release chamber (71) being delimited axially by said first axial side of the release housing (37) and by a first axial side (73a), closed, of the release piston (73), which is formed as a hollow cylinder, the second front axial side of which is open and formed by an annular end (73b), and the cylindrical wall of which, which defines an interior space, slides against the cylindrical wall of the release housing (37) between the rest position, in which the release piston (73) abuts by its first axial side (73a) against a shoulder (37a) of the release housing (37), and the release position, in which the release piston (73) abuts against an axial stop (57a) carried by the plug (57), the at least one retaining element (60) being carried by the plug (57) and, in the armed position, the at least one holding member (55) extending into the release housing (71) through the through bore (56) of the plug (57) so that it can be gripped by the at least one retaining element (60) in the locking position, the at least one retaining element (60) being configured to be located, in the locking position, on the path followed by the annular end (73b) of the release piston (73) during its movement from the rest position to the release position, so as to be moved from the locking position to the unlocking position by the annular end (73b) of the release piston (73) pushing against the at least one retaining element (60).

5. - The device (1) according to claim 4, characterized in that it comprises a plate (57b) which is located in the interior space defined by the cylindrical wall of the release piston (73) and is fixed to the plug (57), and at a distance therefrom, by spacers (57c), the plate (57b) thus having a first face facing the first axial side (73a) of the release piston (73) and a second opposite face on the side of which the at least one retaining element (60) is located, the axial stop (57a) being carried by the first face of the plate (57b) and the means (74) for returning the release piston (73) to the rest position being elastic return means, such as a compression spring, bearing on the first face of the plate (57b) and pressing against the first axial side (73a) of the release piston (73).

6. - The device (1) according to any one of claims 1 to 5, characterized in that the at least one retaining element (60) is movable between the locking position and the unlocking position by pivoting.

7. - The device (1) according to claim 6, when depending on claim 4 or 5, characterized in that it comprises two retaining elements (60) each pivotally mounted about a respective pivot pin (61) which is integral with the plug (57), each pivot pin (61) belongs to a plane perpendicular to the longitudinal axis (A1) of the launch tube (3) and is perpendicular to a longitudinal plane of the launch tube (3), the device (1) further comprising means (62) for elastically returning the retaining elements (60) to the locking position.

8. - A method for launching drones (2) using a launch device (1) using spring thrust as defined in any one of claims 1 to 7, characterized in that it comprises the following successive steps: - a positioning step, comprising positioning a drone (2) in the launch chamber (34), the ejection assembly (5) being locked in the armed position; - a step of launching the drone (2), comprising introducing into the release chamber (71) sufficient gas pressure to move the release element (70) from the rest position to the release position, whereby the ejection assembly (5) is unlocked and ejects the drone (2) from the launch tube (3); and - before the positioning step is repeated, a repositioning step, comprising returning the ejection assembly (5) to the armed position, in which it is locked by the at least one retaining element (60).

9. - A tool (9) for implementing the method as defined in claim 8, characterized in that it comprises a carriage (10) movable in translation along at least one frame (11) which has, at one end, a drive plate (15), the carriage (10) and the frame (11) being able to be introduced into the launch chamber (34), after the launching step, such that the carriage (10) bears against the ejection element (50) and the drive plate (15) bears against the open end (3a) of the launch tube (3), translation driving means (12, 13) being provided for driving the carriage (10) in translation along the frame (11), by means of which the carriage (10) is movable towards the rear end (3b) of the launch tube (3) so as to compress the ejection spring (51) and return the ejection assembly (5) to the armed position.

10. - The tool (9) according to claim 9, characterized in that the frame (11) further comprises a bottom plate (14) able, in use, to bear against the rear end (3b) of the launch tube (3), and at least one guide rod (16) connecting the bottom plate (14) and the drive plate (15) and along which the carriage (10) is mounted movable in translation, the translation driving means (12, 13) comprise a worm screw (12) and means (13) for driving the worm screw (12) in rotation, the worm screw (12) extending between the bottom plate (14) and the drive plate (15), to which it is connected so as to be rotatable about its longitudinal axis, and passing through a threaded hole in the carriage (10), whereby rotation of the worm screw (12) results in translation of the carriage (10).