FR2535045A1 - PROJECTILE TRIGGER OF AVALANCHES - Google Patents

Abstract

1. Device for triggering avalanches, having a projectile (1) comprising a projectile body (10), a connection piece (14) integral with the projectile body (10), an explosive charge (12), a detonator (18), a striker (28), a tail fin (16) movable along the connection piece (14), the detonator (18) and the striker (28) being arranged so that the striker (28) strikes the detonator (18) during this movement, and means of transmitting the detonation energy of the detonator (18) to the explosive charge (12), characterized in that this device also possesses a launcher tube (2), in which the projectile can be placed, the projectile also having an ejectable pin (34) having a locking position, in which it prevents any movement of the tail fin relative to the connection piece tending to bring the striker (28) closer to the detonator (18), and a spring (36) tending to move the ejectable pin (34) away from its locking position, the pin (34) having one end which can come up against the inner wall of the tube (2) under the action of the spring (36) when the projectile is inside the tube (2), and having such a length that it is still in the locking position when its end is up against the inner wall of the tube (2).

Description

The subject of the present invention is a

  jectile avalanche trigger, and more special-

  a projectile that can be dropped from a helicopter. In mountainous areas, when a mass of snow threatens to provoke an avalanche,

  is preferable, for obvious reasons of

  to artificially trigger this avalanche when no one is nearby There are currently several methods to artificially trigger an avalanche One can use explosive charges placed by hand, in the snow mass or nearby, or use grenades to

  You can also install

  cables or special cables for the transport of explosive

  Finally, one last method uses a pneumatic launcher. The main disadvantage of all these methods is that

  approach the snow mass very closely to

  explosive charges and these processes are therefore not usable in inaccessible places

  to men, except in some cases the pneumatic launcher

  tick whose range is however limited by the relief. The present invention is precisely to remedy this drawback with an avalanche trigger projectile that can be dropped from a helicopter, and thus cause an avalanche in any place, even inaccessible to men '

  According to the main characteristic of the

  jectile object of the invention, it comprises:

  a projectile body containing an explosive charge

ve

  a connecting piece, integral with the projection body

  tile and in which is placed a detonator, and

  a empennage, inside which is placed a person

  cutter, this empennage being able to move along the connecting piece at the time of impact so that the striker comes to hit the primer of the detonator.

  According to another characteristic of this

  jectile, it is equipped with a detonating cord

  end is placed in the connecting piece to the

  of the detonator and at least part of which

found in the explosive charge.

  The projectile is of course equipped with a certain number of safeties intended to prevent an accidental explosion. In a preferred embodiment, it comprises an ejectable pin arranged in such a manner as to prevent any movement of the empennage by

  projectile body direction, this pin can

  In addition, a transport pin connected to said ejector pin can be provided to prevent ejection.

of the latter.

  On the other hand, the projectile may comprise a switch at least part of which is in the connecting piece between the detonator and the

  body of the projectile; in this case, the empennage com-

  takes a window that can come opposite said portion of the switch to allow the ejection of the latter during the impact Finally, it is useful to provide a positioning screw screwed into the room

  linkage and the empennage comprises a slot allowing

  both its guidance by this screw during its movement.

  along the length of the connecting piece at the moment of impact. The invention will appear better on reading

  the following description, given purely

  illustrative and in no way limiting, with reference to

attached drawings, in which: -

  FIG. 1 is a diagrammatic view in vertical section of the whole projectile object of the invention,

  FIG. 2 is an enlarged diagrammatic view

  die in section showing the upper part of the projec-

tile of Figure 1, and

  FIGS. 3a to 3c are schematic views

  illustrating the various stages of implementation

  place the projectile in its launcher tube.

  FIG. 1 shows the projectile object of the invention, bearing the general reference 1, placed inside a cylindrical launcher tube 2. The assembly is disposed vertically inside a helicopter and the launcher tube 2 is closed at its lower part by a hatch 6 which can be opened

  thanks to a mechanism 8 on board the helicopter

  The projectile 1 consists essentially of a projectile body 10 inside which is located

  an explosive charge 12, for example a liquid other than

  Asteronizable as the MITROCRO 5848 "A connecting piece 14, disposed at the upper part of the projectile body 10, is secured to it, for example by screwing, while a empennage 16 is

  mobile in translation along the piece 14.

  The latter appears better on the enlarged view.

  FIG. 2 shows, inside the launcher tube 2, the projectile body 10 containing the explosive charge 12 while the connecting piece 14

  is screwed into the upper part of the body of

  jectile 10 A seal 56, arranged at the bottom of the part 14, protects the load 12 against moisture The connecting piece 14 has the shape of a hollow cylinder containing at its upper part a detonator 18, while a detonating cord 20, also placed inside the connecting piece

  14, has an end 21 placed in the vicinity of the detonation

  18 and its other end (not shown) inside the explosive charge 12 The empennage 16 consists essentially of a cylindrical body 24

  hollow whose inner diameter is slightly greater than

  the outer diameter of the connecting piece 14 so that it can be smoothed on it.

  is attached to a plate 30 which closes the body of empennets

  Swing 24 to its upper part During the impact on the ground, by inertia, the empennage 16 slides along the connecting piece 14 and the fins 26 come to a position 26 a schematically represented in outline

  The role of the fins 26 is uni-

  to ensure the stabilization in flight of the projec-

  The striker 28 strikes the primer 32 of the detonator 18 and the energy of the explosion is transmitted to the

  charge 12 via the detonating cord 20.

  It is obvious that a more or less important

  the aunt of the latter must be inside the load 12 and in contact with it to ensure

  the good transmission of the explosion.

  However, in order to avoid an explosion

  the projectile is equipped with a certain number of

  security which are all visible on the

figure 2.

  We first see in Figure 2 a res-

  fate 29 surrounding the firing pin 28 and one end

  mité is fixed to the plate 30 Its role is to brake a possible movement of the empennage with respect to the connecting piece, movement that could occur after release of the pin 34, to prevent the striker 28 does not hit the primer 32 This movement is, however, unlikely because of the resistance of

  the air which tends to hold the plate 30 upwards.

  Another security is constituted by an ejector pin 34 which passes through the empennage body 24 of

  part and is, in the position of trans-

  port shown in Figure 2, above the room of

  link 14, thus preventing any movement of the

  a spring 36 bearing on the one hand on the head 38 of the pin 34 and, on the other hand, on the outer face of the tail body 24, allows ejection of the pin However, it is seen in the figure that, as long as the projectile is inside the launcher tube 2, the pin can not be ejected since its head abuts against the inner wall of the tube The ejection takes place only

  once the projectile is outside the

  be, therefore immediately after release O However, to avoid the ejection of the pin 34 when handling the projectile or the assembly constituted by the empennage and the connecting piece outside the launcher tube, one

  provided a transport pin 40 connected to the gou-

  This pin 40 is inserted into the pin 34 at a point located outside the body.

  empennage 24 and diametrically opposed to the point of ap-

  spring 36 The pin 40 is removed from the

  just before dropping the projectile.

  Another security has been planned to avoid

  the transmission of an accidental explosion of

  18 to the detonating cord.

  saw a switch consisting essentially of an interruption block 44 disposed inside the room of

  14 between detonator 18 and the detachment cord

  This block 44 constitutes a barrier which prevents

  the shockwave to propagate

  The block 44 is secured to an ejector rod 46 on which is fixed an end of a spring 48 whose other end is fixed to a support pad: the role of the spring 48 is to cause the ejection from the block 44 at the moment of impact It is seen on the detail along the arrow v that the empennage body 24 has at this location a window 52 whose lower portion 53 has dimensions such that only the ejection rod 46 can through the wall of the empennage body, thus preventing the block 44 from being ejected when the vehicle is in the transport position. At the moment of impact, when the empennage begins to slide along the part 14, the part greater than the large size of the window 52 comes opposite the block 44 This is then, with respect to the window, in the position 44a and is ejected under the action of the spring 48 Finally, we still see on the Figure a positioning screw 54 that plays several r Ales First, e It is the link between the

  empennage body 24 and the connecting piece 14

  on the other hand, it serves to block the detonating cord 20 inside the latter, and finally, thanks to a

  longitudinal slot 55 formed in the body of empen-

  24, it allows the guidance of the latter during

  its movement along the connecting piece.

  The placement of the projectile in its tube

  launcher is illustrated in Figures 3a to 3c.

  In Figure 3a, we see that the first operation is to place the body 10 of the projectile

  only inside the tube 2 A positioning rod

  7 is, in this operation, in the locking position shown in FIG. 3 thus preventing the projectile body 10 from descending

  up to the hatch 6 The location of the posi-

  7 is that the upper body is in the vicinity of the upper part of the body.

  launcher tube 2 The hatch 6 located in the lower part

  the tube is closed and will only be open

  moment of the drop It is when the body of projection

  The tile is in the position illustrated in FIG. 3a, which is filled with the explosive charge. Meanwhile, the assembly consisting of the empennage and the connecting piece is prepared separately. detonating cord 20 in the slot provided for in Exhibit 14.

  screwed into the upper part of the body of projec-

  as shown in Figure 3b, and then remove

  the positioning pin 7 and let the projectile slide slowly along the tube 2: thus we arrive at the position of FIG. 3c, in which the

  nose 5 of the projectile is in contact with the trap-

eg 6.

  The operation of the device will now

  can be described with reference to FIG. 20 When the helicopter is above the place where the

  projectile must be dropped, the first step is to remove the

  At this moment, the spring 36 pushes the pin 34 to the right of the figure, but the head 38 of the pin abuts against the inner wall of the launcher tube 20 is then opened the hatch 6 located at the bottom. of the tube and the projectile falls in free fall As soon as the empennage is out of the launcher tube, the spring 36 causes ejection of the pin 34 and the empennage body 24 is then free to slide along the connecting piece 14 When the projectile touches the ground, by

  inertia, the empennage body 24 moves abruptly

  along the connecting piece 14 towards the projectile body 10 During this movement, the upper part of the window 52 passes in front of the

  block 44 and the spring 48 allows the ejection

  On the other hand, the movement of trans-

2535,045

  the empennage 16 along 14 is

  guided by the slot 55 which moves in front of the screw 54.

  The inertia of the empennage 16 is sufficient to overcome

  the action of the spring 29, and the firing pin 28 strikes the primer 32 of the detonator 18. As the switch 44 has been previously ejected, the energy of

  the explosion is transmitted to load 12 through

medium of the detonating cord 20.

  The projectile object of the invention has particularly interesting advantages since it can be dropped anywhere from a helicopter, and in particular in places inaccessible to men Moreover, it is simple and easy to implement and safe operation since it is equipped

  a large number of securities -Finally, we can

  several projectiles and several launching tubes

  of this kind aboard a single helicopter in order to

  It is understood that the invention is not limited to the single embodiment that has just been described, but that it is possible to envisage several avalanches at locations distant from one another during the same flight. variants without going out for

as much of the scope of the invention.

Claims (5)

  1 Avalanche triggering projectile, characterized in that it comprises   a projectile body (10) containing an ex-   plosive (12) a connecting piece (14), integral with the body of   projectile (10) and in which a detachment is placed   (18), and a empennage (16) e inside which is placed a   striker (28), this empennage being able to move   along the connecting piece (14) at the moment of impact so that the striker (28) strikes the primer (32) of the detonator (18)   2 o Avalanche trigger projectile se-   11, characterized in that it comprises   takes a detonating cord (20) one end (21) of which is placed in the connecting piece (14) in the vicinity of the detonator (18) and at least part of which is in the explosive charge (12) o   3 Avalanche Trigger Projectile Se-   lon claim 1 e characterized in that it com-   takes an ejector pin (34) arranged to prevent movement of the empennage (16) towards the projectile body (10), which pin (34) can be ejected under the action of a spring (36).   4 Avalanche trigger projectiles se-   according to claim 3, characterized in that   carries a transport pin (40) connected to the gou-   ejection pin (34) to prevent the ejection of the latter.   Avalanche trigger projectile se-   according to claim 1, characterized in that   takes a switch of which at least part (44) is 25350 f 45   located in the connecting piece (14) between the detonation   tor (18) and the body (10) of the projectile and in that the empennage (16) comprises a window (52) facing the portion (44) of the switch in order to allow the ejection of this last when the impact.   6 Avalanche trigger projectiles se-   according to claim 1, characterized in that   takes a positioning screw (54) screwed into the connecting piece (14) and in that the empennage (16) has a slot (55) allowing its guidance by the screw (54) during its movement along the room (14) at the moment of imlpac :.