FR2646503A1 - DEVICE FOR EJECTING CONTAINERS ON TRAJECTORY - Google Patents

Abstract

The technical sector of the invention is that of devices making it possible to eject on a path and in a radial direction from a vector, containers arranged inside the envelope of the latter. The ejection device according to the invention is characterized in that it comprises, on the one hand, a detonating charge 4 disposed at the level of the axis of the vector 1 and extending substantially over the entire length of the set of containers 2, and on the other hand means ensuring the confinement of this charge, and in that the containers are kept in contact or integral with the confinement means by holding means at the time of the initiation of the detonating charge, the contact or common surface 6 being such that its trace in radial section has a perpendicular bisector 7 having a radial direction relative to the vector. Application to the dispersion of mines from a projectile.

Description

The field of the present invention is that of devices enabling

  to eject on a path and in a radial direction of a vector, containers arranged

  inside the envelope of the latter.

  A vector must be understood to mean a mobile following an own trajectory whether it is after firing from a launcher (in this case the vector will be a projectile such as a rocket), or after being dropped from an aircraft (bomb,

submunition transporter).

  The vectors ejecting containers on trajectory are today relatively widespread. They are used both for the dispersion of autonomous sub-projectiles equipped with self-directed devices and able to search each their target, as for the dissemination of mines or bomblets

anti-vehicle or anti-personnel.

  The effectiveness of such vectors is directly related to the good dispersion of the containers, in fact it is totally excluded to see them interfere with each other at the time of their release (in the case of subprojectile to pursue a clean trajectory), or fall on the ground

  in a grouped way (in the case of mines).

  In order to avoid such drawbacks, it has been sought to ensure rapid radial ejection and with a speed

initial important.

  Patent EP0169956 describes a first type of solution in which the sub-projectiles are kept together.

  an annular support by means of locking flanges.

  After removal of the outer casing, a gas generating charge is initiated and causes on the one hand the release of the locks and on the other hand the ejection of

sub-projectiles by pistons.

  Such an ejection device is very complex which increases the risk of malfunctions. In addition, the ejection speed is limited by the inertia of the mechanical parts - in the presence, and is also related to the elasticity of the locking latch which is maintained in stress during the entire storage time of the vector, losses of mechanical characteristics are therefore at

  fear which decreases the reliability of this device.

  The patents FR2591735, EP0265608 and EP0265609 describe other ejection devices in which a gas-generating charge disposed at the level of the vector axis.

inflates one or more bags.

  Such a device is limited in terms of the speed of ejection by the time required to inflate the bags. In addition, the flexible bags being kept folded inside the vector, a degradation of their characteristics. mechanical hazards, which can lead to either an asymmetry of the inflation, thus the ejection, or a rupture of one of the bags prohibiting

thus the dispersion.

  It is the object of the present invention to provide an ejection device which ensures the symmetry of the distribution of the containers and a high speed. ejection

  while maintaining a very high level of reliability.

  Thus, the subject of the invention is a device for ejecting, on a path and in a radial direction, containers arranged in a ring inside the envelope of a vector, characterized in that it comprises a a detonating charge disposed at the level of the vector axis and extending substantially the entire length of all the containers, and secondly means ensuring the confinement of this load, and in that the containers are kept in contact or secured to the confinement means by holding means at the moment of initiation of the detonating charge, the contact or common surface being such that its radial sectional trace has a mediator having a relatively radial direction

to the vector.

  The confinement means may comprise a cavity

  constituted by the juxtaposition of the different containers.

  Containment means may also include a

  case that is in contact with the containers.

  According to a particular embodiment, in the case where the containers each have at least two planar faces separated by an intermediate surface limiting the cavity, the flat faces of two adjacent containers are held in mutual contact by the holding means and are oriented radially. relative to the vector, and in radial section, the angle formed by the traces of the two flat faces of each container bisects the mediator of the trace of the intermediate surface of the container

considered.

  The fragmentation means may comprise cutting cords arranged facing the envelope along an axial direction of the vector, for example in the

  extension of the flat faces of the containers.

  The holding means may comprise at least one cylindrical band surrounding all the containers and

  disposed so as to be broken by the cutting cords.

  The device according to the invention will preferably include an ignition system whose firing is controlled by a rocket and which causes the initiation of the cutting cords and the detonating charge by

via a delay.

  The invention can be applied to a vector such that the set of containers has a symmetry of rotation of order three relative to its axis, and that the containers

are mines.

  The invention will be better understood on reading the

  following description of particular modes of

  realization, description made with reference to the drawings

  in which: Figure 1 is a schematic axial sectional view of a container disperser vector equipped with an ejection device according to a first embodiment of the invention. Figure 2 is a sectional view along the plane A-A of

Figure 1.

  FIG. 3 is a radial sectional view of a vector equipped with an ejection device according to a second embodiment of FIG.

embodiment of the invention.

  Referring to FIG. 1, a vector 1, which is a projectile with a reduced rotational speed such as a rocket, comprises a rear part 15 on which will be arranged an unrepresented tail, an envelope 3, and an ogive 14 containing a rocket 20 as well as an ignition system that

  will be described in more detail later.

  The envelope 3 encloses a number of containers 2 which are here dispersible mines, of the type for example of

  those described in patents FR2475716 and FR2448708.

  The internal structure of these mines is not the subject of the present application and will therefore not be described further in

detail.

  Referring to Figure 2 which is a section of the previous in a radial direction, we see that the

  mines are arranged in a ring around the axis of the vector.

  The envelope thus contains a stack of several layers, each layer consisting of a group of three mines regularly distributed around the axis of the vector. Each mine comprises at least two lateral plane faces 9 separated by a so-called intermediate surface 6. The flat faces of the various mines constituting a group of three are held in mutual contact by holding means which comprise a metal strip 11 substantially

  cylindrical surrounding each group of three mines.

  The holding means also comprise triangular spacers 12 which are interposed between each group of three mines and which are arranged in

  notches 16 made on the mines.

  There remains a relative game in the axial direction of the vector between spacers and mines so that the

  mines belonging to two successive groups are mutually

  in contact with their upper faces 18 and

respective lower 19's.

  These spacers ensure the rotational joining of the mines constituting a group at a time between them and

with those of the next group.

  A housing 17 is arranged at the vertices of each spacer 12. A longitudinal wedge 13, extending over substantially the entire length of the vector 1, is

  disposed at each group of superimposed dwellings.

  The wedges carry means of fragmentation of the envelope 3 which are constituted here by longitudinal cutting cords 10 of known type (for example

  hexogen cords under lead sheath).

  Two circular cutting cords 24 (only the front cords are represented), arranged at the front and rear part of the vector, are intended to separate the ogive 14 and the rear part 15 from the remainder of the vector and complete the means of

fragmentation of the envelope.

  The metal strips 11 make the cutting cords 10 and the longitudinal shims 13 of the assembly integral with each other.

  formed by spacers 12 and mines 2.

  The holding means thus described thus make all the mines and the cutting means integral. The subset thus formed is secured to the vector in rotation and in translation in a conventional manner and not

shown in detail.

  For example, to make the connection in rotation, provide driving pins arranged between the rear portion 15 and the spacer 12 of the first

group of mines.

  The last group of mine (on the side of the warhead 14) bears on a cover 25 which carries the circular cord 24 in a peripheral groove and which is secured to the warhead and the envelope for example by pins radials. The cover has notches allowing it to receive the spacer 12 which ensures its connection in rotation with the last group of mines. It also carries an orifice 26 allowing the passage of a hexagonal line which constitutes a detonating charge 4 whose function will be studied hereinafter, sealing means (here joints

  O-rings) are interposed between the orifice 26 and the load 4.

  The translational fastening of the envelope with all the mines will therefore be ensured by the support of the upper faces of the last group of mines on the cover 25 as well as by the support of the first group of mines on the

rear part 15.

  The rear portion will carry the second circular cutting line for example at a circular groove on a second cover similar to the cover 25 but having no passage for the detonating load. The thus secured mines leave substantially at the level of the axis of the vector a cavity 5 of triangular section which is delimited mainly by the juxtaposition of the various intermediate surfaces 6 of each of the mines and the lateral surfaces of the

spacers 12.

  The stacked mines have relative contact surfaces, on the one hand between the mines constituting a group of three (flat faces 9), and on the other hand between the different groups of mines (upper faces 18 and

lower 19).

  The detonating charge 4 is disposed inside the cavity 5 and it extends substantially over the entire length of the cavity 5, thus over the entire length of the set of mines. The cavity 5 thus delimited constitutes a means of

  containment for the detonating load 4.

  The confinement means are completed by the lid carrying the sealing means and by the

  closed lid arranged at the base.

  The mines, delimiting the cavity 5 by their intermediate surfaces 6, are integral with the confinement means

thus creates.

  The intermediate surface 6 of each mine has a mediator, marked at 7, whose direction is radial relative to the vector. This mediator 7 is also the bisector of the angle formed by the flat faces 9 of the mine in question.

  The spacers 7 have a relative angular orientation

  groups of mines such that the cutting cords 10 are arranged in the extension of the

flat faces 9 of the mines.

  Figure 1 also shows schematically the ignition system of the cutting cords 10 and

the detonating charge 4.

  The ignition system comprises a first relay 21 which is initiated by the fuse 20, a delay system 22,

  constituted here by a delayed pyrotechnic composition

  trice, but any other type of delay, in particular

  tronic could be considered, and a second relay 23.

  The first relay 21 includes three radial outputs

  corresponding to the three cutting cords 10.

  The second relay 23 is connected to the detonating charge 4.

  The delay system ensures that fragmentation of the projectile envelope is initiated prior to initiation

the detonating charge 4.

  The value of the delay will depend on the celerities of the explosives used for the cutting cords and the detonating charge, as well as the distance between the first

  relay 21 and the generatrices of the vector which are cut.

  In the usual case of a projectile with a low rotational speed (of the order of ten revolutions seconds), a delay of between 50 and 100 milliseconds is sufficient to guarantee that the confinement is still effective at the moment o

the detonating charge is initiated.

  The operation of the vector is as follows, the rocket 20 of the chronometric type causes the initiation of the first relay 21 at the end of a programmed time before firing or controlled on trajectory, the three longitudinal cutting cords are then initiated simultaneously and that the

delay composition 22.

  Connections of type tee known and not shown which are integral with the cover 25 will initiate the circular cutting line 24, by one or more of

longitudinal cords 10.

  Similar connections will allow the initiation of

  circular cord located at the base.

  The cutting cords 10, fragment in the same

  time the envelope of the vector and the cylindrical bands 11.

  At the end of the combustion of the delay 22, the charge

  detonating 4 is initiated in turn.

  By choosing a value of the delay as described above, the state of the charge 4 occurs before the mines have begun to deviate from each other under the effect of the centrifugal force, and it causes a violent wave radial direction shock which exerts

  on the intermediate surfaces 6 of each of the mines.

  The mediators of the intermediate surfaces being also the bisectors of the angles formed by the plane faces 9 of each of the mines, the latter are dispersed in a radial direction, and

  the energy of the shock wave is used optimally.

  A number of tests were carried out with a detonating charge in the form of a lead-sheathed hexogen line, associated with cutting cords also in hexogen under lead (detonation velocities in the order of

7000 m / s).

  By varying the linear concentration of hexogen between 3 and 40 grams / meter, ejection speeds of the mines were obtained between 3 and 30 meters / second,

  the mass of each mine being of the order of 2 kilograms.

  It is worth noting the relatively unusual aspect of the use here of detonating cords. Indeed, these are usually used to transmit between their ends information under the

form of a detonation wave.

  An incidental radial effect is used here that can actually be exploited because of the presence of

means of containment.

  It is possible to choose pyro-

  different techniques for carrying out the detonating load, provided that such composition does have a

  detonating regime (celerity of the order of 7000 mis).

  It would be possible to use different compositions of celerity for the cutting cords and for the detonating load, in this case we will play on the value of the

  delay given by the composition 22.

  It will also be possible to interpose a damping material between the detonating charge and the intermediate surfaces 6 delimiting the confinement. It is then possible, using the characteristics of compressibility and transmission damping of the shock wave of this material, to use more violent detonating charges, or else to modulate the value of the ejecton velocities.

  mines without modifying the detonating charge.

  It is possible to use the device according to the invention for ejecting containers having a profile.

any geometrical

  Figure 3 represents in radial section a vector

  for ejecting cylindrical mines on trajectory 2.

  These mines are stacked inside the envelope 3 of the vector and are, as in the previous variant,

  disposed in a ring around the axis thereof.

  The envelope thus contains a stack of several groups of mines, each group comprising three mines

  regularly distributed around the axis of the vector.

  The holding means comprise, as before, three longitudinal shims 13, which in this case are in contact with the outer cylindrical surface of the mines, as well as

than linear bands 11.

  The rotational joining of the envelope with all the mines and holding means is performed in a known manner not shown, for example by integral keys of the casing and bearing on the longitudinal wedges, these keys will not interfere. not

the radial ejection of mines.

  The confinement means are constituted here by a holster

  8, inside which is disposed the detonating charge 4.

  The case is made of plastic material of the polyethylene type. The mines are held by the holding means in contact with the case at a cylindrical contact surface 6. In radial section, the mediator of the trace of this surface of contact which is thus a bow of cerele is the normal in the middle of this arc and presents a direction

radial.

  The three cutting cords 10 are integral with the longitudinal shims as in the previous variant, they are also arranged so as to cut the strips

cylindrical 11.

  They are regularly distributed angularly, and in such a way that the radial direction of the vector passing through each cord is bisecting the angle formed by the two mediators 7 relative to the mines adjacent to said cord. This ensures a homogeneous radial dispersion of the mines. Since the mines are kept in contact with the confinement means constituted by the case 8, the detonation of the charge 4 will cause the dipersion of the mines in the

  radial directions materialized by the mediators 7.

  It is obviously possible to adapt the invention to everything

  other type of radial dispersion of containers.

  It is thus possible to provide a vector in which each group of containers comprises more than three elements, the shape of the case and holding means will be adapted accordingly, and the detonating charge will also be chosen as a function of the mass. to disperse and

the desired ejection speed.

  It is also possible to adapt the invention to projectiles whose rotational speed is greater, it will suffice, to prevent the centrifugal inertia separates the containers from the means of containment before detonation of the explosive charge, to provide, in complement of the cylindrical strip 11, shearable holding means which ensure the cohesion of all the containers after

cutting of the envelope 3.

  For example, in the case of the embodiment represented in FIG. 1, it is possible to provide shear pins arranged in housings made on the notches 16 so as to prevent any radial translation of the mines.

  relative to the spacers 12 corresponding.

Claims (7)

  1-device for ejecting, on a path and in a radial direction, containers (2) arranged in a ring inside the envelope (3) of a vector (1), characterized in that it comprises on the one hand a detonating charge (4) disposed at the axis of the vector (1) and extending substantially the entire length of the set of containers (2), and on the other hand means ensuring the confinement of this charge, and in that the containers are kept in contact or secured to the confinement means by holding means at the moment of initiation of the detonating charge, the contact or common surface (6) being such that its trace in radial section has a mediator (7) having a radial direction relative to the vector.   2-ejection device according to claim 1, characterized in that the confinement means comprise a cavity (5) constituted by the juxtaposition of different containers (2).   3-ejection device according to one of claims 1 or   2, characterized in that the confinement means comprise a case (8) which is in contact with the containers (2).   4-ejection device according to claim 2 and applied to containers (2) each having at least two planar faces (9) separated by an intermediate surface (6) limiting the cavity, characterized in that the flat faces (9) of two adjacent containers (2) are held in mutual contact by the holding means and are oriented radially relative to the vector (1), and in that, in radial section, the angle formed by the traces of the two planar faces of each container bisecting the mediator (7) of the trace of the intermediate surface (6) of the container in question.   -Device according to one of claims 1 to 4,   characterized in that the fragmentation means comprise cutting cords (10) arranged opposite the envelope (3) along an axial direction of the vector (1).   6-Device according to claims 4 and 5, characterized   in that the cutting cords (10) are arranged in the   extension of the planar faces (9) of the containers (2).   7-Device according to claims 5 or 6, characterized   in that the holding means comprise at least one cylindrical band (11) surrounding all the containers (2) and arranged so as to be broken by the cords of cutting (10).   8-Device according to one of claims 1 to 7,   characterized in that it comprises an ignition system firing is controlled by a rocket (20) and which causes the initiation of the cutting cords (10) and the detonating charge (4) via a delay (22). 9-Vector integrating an ejection device according to a   Claims 1 to 8, characterized in that the entire   containers (2) has a rotation symmetry of order   three relative to the axis of the vector (1).   -Vector according to claim 9, characterized in that the containers (2) are mines.