FR2547909A1 - DEVICE FOR STARTING AN EXPLOSIVE LOAD - Google Patents

Abstract

DEVICE FOR INITIATING AN EXPLOSIVE CHARGE WITH A PRIMING CHARGE FOR ACCELERATING IN DIRECTION OF THE SAID EXPLOSIVE CHARGE AN ARMATURE OF INERT MATERIAL. THE PRIMING CHARGE 8 SHOWS A RECESS 7 DELIMITED BY THE PRIMING ARMATURE 9 TO RECEIVE THE EXPLOSIVE CHARGE 3 IN WHOLE OR PART, THIS RECESS 7 HAVING A TRANSVERSAL EXTENT AS WITH A CENTRAL ARRANGEMENT OF THE EXPLOSIVE CHARGE IN THIS EVIDENCE THERE IS BETWEEN THE PERIPHERY OF THIS ONE AND THE PRIMING REINFORCEMENT 9 A FREE SPACE 10 FOR THE ACCELERATION OF THIS LATTER. THE INVENTION APPLIES IN PARTICULARLY TO LOADS INCLUDING AN INTERIOR COATING FORMING A DART, A REINFORCEMENT FORMING A DART, OR A REINFORCEMENT FORMING PROJECTILE.

Description

i

  Device for priming an explosive charge.

  The present invention relates to a device for priming an explosive charge, in particular of the type comprising a liner forming a dart, a dart armor or a projectile armature,

  with a priming charge to accelerate in the direction of said explosive charge a starting frame of inert material.

  German patent application P 30 17 785 6-45 10 describes, among other things, the manner in which, for its priming by a front face, an explosive charge in a body of revolution

  it is associated with itself a charge and a priming armature so that the latter is located in the air, facing said front face of the explosive charge and at a predetermined distance from this same face.

  The subject of the invention is such an improved priming device so that, despite a significantly reduced space in the longitudinal direction of the explosive charge to be initiated,

  a dynamic barrier opposed to the latter is provided in a measure hitherto unrealizable.

  This priming device is characterized in that the priming charge has a recess delimited by the priming armature to receive the explosive charge in its entirety or at least in a zone, this recess having an integral transverse extension. that with a central arrangement of the explosive charge there remains between the periphery of the latter and the priming armature a free space of acceleration for the latter. According to other advantageous advantageous features of the invention: in order to fix the free space of acceleration between the priming armature and the explosive charge, the recess encloses in the zone near the top of the armature of priming a spacing piece of inert material, preferably in the form of a cone-narrowing insertion liner towards the priming charge; in the case of an explosive charge of the hollow load type with inner lining or armature in a body of revolution or of the cutting load type with reversion or armature symmetrical with respect to a plane, the hollow load or the cutting load and the armature With the aid of the free space of acceleration, the starting material has a contour identical or at least similar to that of the coating or reinforcement of the hollow charge or the coating or reinforcement of the cutting load, and also possibly also the boot load on its side 8 not turned to the free space of acceleration; in the case of a dart cover, a dart-shaped armature or a conical projectile with an opening angle 2 a, the corresponding explosive charge and the priming armature have a clearance surface each a limiting surface conical with respective opening angles 2 P and 2 Y; the igniting charge has on its side not rotated 15 towards the free space of acceleration a conical limiting surface with opening angle 2 y; the opening angle 2 y of the priming armature is larger than the opening 2 P of the explosive charge; the opening angle 2 y of the priming armature is 20 equal to the opening angel 2 of the explosive charge; the opening angle 2 P of the explosive charge is greater than the opening angle 2 'of the priming armature and the difference of the angles -y is smaller than the angle 2' than the armature of the armature priming forms with its starting position after initial acceleration by the priming charge; the opening angle 2 P of the explosive charge is greater than the opening angle 2 t of the ignition armature and the difference of these angles C-> is equal to the angle 2 that the armature priming means forms with its starting position after initial acceleration by the priming charge; the opening angle 2 of the explosive charge is greater than the opening angle 2 Y of the priming opening

  and the difference of these angles p-t is greater than the angle 2 which bootstrap forms with its starting position after initial acceleration by the firing load.

  The realization of the measures provided by the invention poses no problem. They have the advantageous result of a compact structure and a perfect adaptation of the device to any type of direct ability to achieve a dynamic dam of optimum power for the load. explbsive / prime With regard to the priming load, determining in this respect, its recess and the priming armature therein, the ranges of variation in this area are large enough that, even in case of a hollow charge type with an inner liner forming a dart, a dart or a projectile lining which is in the form of a body of revolution or of the type of cutting load with lining or a dart or projectile lining which are symmetrical with respect to a plan, we can exert, by the dynamic barrier opposed to the said explosive charge, a Judicious influence on the process of formation of the sting or projectile, by the effect of the phase vi vph with which the priming frame strikes the hollow charge or the cutting load as well as by the effect of the contour and the extent of the surfaces involved in the process. 'impact. In this respect, it is found that, in the zone of the top of the priming armature, the recess of the priming charge contains, between said priming armature and the hollow or cutting charge to be primed, a spreader made of inert material, preferably in the form of an insertion liner which tapers conically towards the latter. On the one hand, an exact fixing of the free space of acceleration, in which the energy of the priming charge is summed for the acceleration of the priming armature But, on the other hand also, from the neighboring zone of the top of the armature of In this case, it is not possible to form any sting capable of disturbing the subsequent course. By this is meant, for example, an undesired prelay of the hollow charge.

  or cutting in the area close to the axis.

  For the vph phase speed already mentioned, an angle 35 is important, namely the angle at which the priming frame strikes the explosive charge to be ignited. If said explosive charge and the priming armature are on the side of the acceleration free space each a limiting surface -4-. conic with respective opening angles 23 and 2 Y / there exists between the angles ë, A, 'and 2, with 24 as the distortion angle that the priming armature forms with its starting position after the initial acceleration the following relation: e = 26 (Y) The following five cases can be distinguished: first case: &> 2 J for 'Y> f 2nd case: = 2 for' = 3rd case: O> O for 3> and 2 &> ((-A) 4 th case: O = O for 2 j = (Y) e case: O 'for P> and 2 J <(c) For each of these cases we find another phase velocity Vph If the detonation is introduced into the charging charge in such a way that the detonation dot shaves the priming armature, the angle J is given by the Taylor formula: sin C = Vo / 2 D, in which vo designates the speed of the priming armature 20 and D the detonation velocity of the priming charge. In this situation, in the situation considered, the following formula is used for the determination of phase speed: s in 2 Vph = sin D'o, for the five cases of the aforementioned 1 case: vph <D 2 e case: Vph = D 3 e case: Vph> D 30 4 th case: vph = oe case: vph s' reverse. vph These various cases are all important The explanation is given below: o Vph <O Here, the result to be obtained depends on the ratio of the detonation velocity D 'of the explosive charge to be initiated at the speed of defetetonai-n and ciarged d priming and

  Vph phase velocity of the priming armature.

  If D is significantly larger than D and D 'smaller than Vph, the impact of the reinforcement on the explosive charge

  causes the boot of the latter.

  If D 'is larger than vph, the priming armature additionally constitutes a certain "dynamic" barrier delaying the expansion of the gases of the explosive charge, or causing a

compression of these.

  Vph = D l O 1 O If the detonation velocity D 'of the explosive charge to be primed agrees with the phase velocity Vph of the priming armature, the latter represents a pure dynamic barrier without at the same time constituting a means guiding

the detonation wave.

  In this case, the impact of the priming armature on an explosive charge causes a detonation profile determined in the latter, that is to say that here the priming armature 20 constitutes as well a dynamic dam that also a means of guiding the detonation wave, vp = C:> O This limiting case is interesting in that the load

  explosive is initiated by the impact of the priming armature simultaneously on the entire impact surface.

  Reverse Vph Here the priming of the explosive charge by the armature this

  is performed from the base of / last, which is equivalent to a guidance of the detonation wave particularly influenced.

    In the case of an explosive charge to be primed in the form of a hollow charge or a cutting load with a static angle of facing or reinforcement a, the following shall be added: in cases 1 to 3 above, the dynamic collapse angle of the cladding or reinforcement in mutual collision is

  in general larger than their static angle a.

  In the fourth case, it is necessary to note the concordance between the dynamic angle of collapse and the angle

  static if the angle p of the hollow charge or the cutting load also coincides with the static angle a.

  Finally the 5th case results in a dynamic collapse angle smaller than the static angle a.

  The invention will be better understood with the aid of the detailed description of several embodiments taken

  as nonlimiting examples and diagrammatically illustrated by the accompanying drawing, in which: Figure 1 shows a hollow discharge with a priming device; FIGS. 2 to 6 show other embodiments of hollow charges with priming devices

  modified with respect to Figure 1.

  FIG. 1 represents, for example, a hollow charge of revolution 1. The case, the explosive charge and the inner lining of the dart are respectively designated by the references 2, 3 and 4. The inner liner 4 is distinguished, for example, by an outline. tapered opening angle 2a The explosive charge 3 is delimited in the zone 20 of this inner liner by a peripheral surface 5

  aperture angle 23 adapted to the contour of said coating.

  This limiting surface 5 is advantageously covered

  a sheet 6 of aluminum or the like.

  The aforesaid hollow load 1 is arranged concen25 trlquement in a recess 7, for example conical, a priming charge 8 There is, between the limiting surface 5 and an armature of inert material 9 opening angle 2 Y delimiting the recess 7 of the priming charge, a free space 10 for the acceleration of said armature The internal width of this free space is fixed by a spacer 11 of inert material which, in the zone adjacent to the top of the priming frame 9, completely occupies the

  recess section delimited by the latter.

  In the zone of reinforcement 9, the amorphous charge 8 comprises a peripheral limiting surface 12 with an opening angle 2 and a conical contour adapted to that

  of said armature 9, covered with a dam facing 15.

  To introduce dhtonatio into the 8 priming burst, a

  relay-load 15 is contiguous with the front face 14 of this cell adjacent to the top of 9 the armature 9.

  It should be noted that, in this embodiment, the opening angles 2 a, 23, 2 y and 2 are equal to each other. FIG. 2 differs from FIG. 1 only in that, for exactly axial triggering of the detonation in the priming charge 8, the relay load 15 is replaced by a "spike relay" 16 formed of two charges 16 at 10 and 16b coaxial with the priming charge 8 and with the charge generator 1 The charge 16b has, from its edge as far away from the charge of initiation 8, a central point 17 through which it is embedded in Charge 16a The detonation velocity of the charge 16a is thus less than the detonation rate of the charge 16b, this at least in the area of the charge.

tip 17.

  In FIG. 3, the embodiment is modified with respect to FIG. 1 as regards the angles a, A, and Y of the coating 4, of the explosive charge 3, of the armature 9 and of the priming charge 8, in that In other words, the angles α and β are identical to those in FIG. 1, but larger than the angles λ and ρ. In these conditions, the distortion angle, or break, 28 printed on the armature 9 is a function of the thicknesses thereof, the priming charge 8 and the facing of

  dam 13 as well as the nature of the priming charge.

  Figures 3b, 3c and 3d reproduce, in the form of sketches, a detail I of Figure 3a with 23> e -Y (fig 3b) 2 J = t -y (fig 3c) 2 < d 3 -Y (fig 3 d) and, according to the relation = 22 f (fY) 8 <24 (f Ig 3 b): = O (fig 3 c) / QO (fig 2 d) In each of the three In this case, the armature 9 takes, as has already been stated, a velocity of phase e Vh greater than the detonation velocity D of the priming charge 8. If it is assumed that the explosive charge 3 only exhibits a detonation velocity D at most less than or equal to that of said priming charge 8, it is possible, in this explosive charge, for a guiding

  corresponding to the detonation wave.

  By an appropriate choice of the detonation velocity D in the initiation charge 8 and the detonation velocity D 'in the explosive charge 3, it is thus possible to obtain different detonation wave fronts, which offers the possibility of influencing Judiciously on the constitution of the sting of the load

  digs from the lining 4.

  It should also be noted here that the parallelism according to the sketch between the explosive charge 3 and the coating 4, from which the equality of the angles α and A is apparent, has only one example value. 4 may also have a wall thickness increasing or decreasing from the top to the base and the angle P of the explosive charge 3 be different from the angle α of the coating 4 The conical contour of the coating 4 and the 5 limiting surface of the explosive charge is also taken as an example Contours in the form of caps, bells, trumpets or

  tulips are among others also possible.

  This remark concerning the explosive charge 3 and the coating 4 of the hollow charge 1 is equally valid

  for priming load 8 and armature 9.

  FIG. 4 represents an exemplary embodiment in which a hollow charge 22 is concentrically disposed in a recess 19, delimited by a reinforcement 18 made of inert material, of a starting charge 20 leaving a subsisting

  free space of acceleration 21 for said armature 18.

  A simple comparison shows that the explosive charge 23 and the beak-forming coating 24 of the hollow charge 22 are shortened compared to the described embodiments. It is thus taken into account that the coating or reinforcing elements located in the neighboring area of

  at the top of a dart-forming cladding or reinforcement are not present in the tip of the ard when deforming.

  detonatory mating in said coating or armature.

  In this example, the introduction of the detonation into the priming charge 20 is provided on its flat end section 20a by a relay load 25 This end section 20a of the priming load However, it may have an entirely different shape. As far as the recess 19 is concerned, a frustoconical insert insert 26 made of inert material is contiguous with this end section 20a. building elements 10 18, 20, 23 and 24 and excluded elsewhere in its area, narrowed boxes decreasing the working power of detonation gases It follows that in case of detonation, the formation of the tip of the sting This is already done by the elements of the coating 24 which are in the location 27, that is to say in the immediate vicinity of said lining. The rudder speed thus achievable is particularly high because, with the chosen opening angles for the elements of co ntruction 18, 20, 23 and 24, the dynamic collapse angle is relatively small and the priming armature 18 represents for the explosive charge 23 a dynamic dam

at high vph phase speed.

  FIG. 5 represents an embodiment different from that of FIG. 4 solely by modification of the insertion lining 28; Indeed, the latter serves in addition to a receptacle for a safety device of which only a detonator 29 can be seen, to the exclusion, for the sake of clarity, of its other known components. This detonator 29 is intended to firing a firing charge 30 in the axis of its flat end section 30a, against the acting direction of a hollow charge 33, arranged with its coating dart formation 34, as on 4, in a recess 31 of the priming charge 30, so that between its limiting surface 35 and a reinforcement 32 made of inert material there remains a free access space 36 for the latter. It is to be believed that a chamfer 37 such as that shown in dashed lines on the base side of the coating causes no noticeable decrease in power. Fig. 1 shows a priming charge 38 with an armature 39 and a recess 40 for an explosive charge. Ive 41 with foraminous coating Further between the explosive charge 41 and the priming armature 39 is an acceleration free space 43 for this armature. The priming charge 38 and the hollow charge 41, 42 here comprise central bores 44 and 45 through which a tube 46 extends from the priming charge 38 to the c 8 tee of the opposing stub coating 42. At the base For the ignition of the ignition charge 38, a device 10 having suitable conventional means such as an annular foil and a voltage source for

  its release is assembled around the tubs 46 at location 47.

  The inner volume of the tube 46 can be used in many ways, for example for flow technical purposes, for mounting a remote igniter, or as a projectile passage for

rifle grenades.

  The considerations set forth above from the example of revolution body charges apply equally to symmetrical

  report a plan, loads called cutting or roof.

Claims (8)

  1 Device for priming an explosive charge, in particular of the type comprising an inner liner forming a dart, a dart reinforcement or a projectile reinforcement, with a firing charge for accelerating towards the said explosive charge a reinforcing armature. Inert material, characterized in that the priming charge (8, 20, 30, 38) has a recess (7, 19, 31, 40) delimited by the priming armature (9, 18, 32, 39) for receiving the explosive charge (3, 23, 33, 41) in whole or at least in each zone, this recess (7, 19, 31, 40) having a transverse extent such that with a central disposition of the explosive charge in this recess there remains between the periphery thereof and the priming armature (9, 18, 32, 39) 15 a free space (10,21, 36, 43) for the acceleration of the latter .  2 Device according to claim 1 characterized in that, to fix the free space of acceleration between the priming armature (9, 18, 32, 39) and the exploitable load (3, 23, 33, 41 ) the recess (7, 19, 31, 40) of the priming charge (8, 20, 350, 38) encloses in the area near the top of the priming armature (9, 18, 52, 39 ) a spacer (11, 26, 28, 47) of inert material, preferably   in the form of an insertion insert narrowing in the shape of a cone towards the priming load.   3 Device according to any one of claims 1 or 2 characterized in that in the case of an explosive charge of the type chargeeur (1, 22, 33, 41) with lining or armature (4, 24, 34, 42) in a body of revolution or 30 of the type cutting load with coating or symmetrical reinforcement   relative to a plane, the loader (1, 22, 23, 41) or the cutting load as well as the reinforcement cb (9, 18, 32, 39) have the cost of the free space of acceleration (10, 21, 36, 43) a contour identical or at least similar to that 35 of the coating or the armature of the hollow charge (4, 24, 34, 42) or coating ordi reinforcement of the cutting load, and likewise possibly also the priming charge (8, 20, 30, 38) on its side not turned towards the free space of acceleration (10, 21, 36, 43).   4 Device according to claim 3 characterized in that in case of coating (4) forming dart, dart-shaped frame or tapered projectile opening angle 2a, the corresponding explosive charge (3) and the armature d priming (9) have the side of the free space of the acceleration (10)   each a conical limiting surface with respective aperture angles 2 p and 2 y.   Device according to any one of Claims 3 or 4, characterized in that the amlogging charge (8)   it has a cone-limiting surface (12) with an opening angle 2 t on its non-turned-over position (10).   6 Device according to claim 4 characterized in that the opening angle 2 Y of the priming armature (9) is greater than the opening angle 2 P of the load explosive (3).   7 Device according to claim 4, characterized   in that the opening angle 2 of the cushioning armature (9) is equal to the opening angle 2 v of the explosive charge.   8 Device according to claim 4 characterized in that the opening angle 2 P of the explosive charge (3) is greater than the opening angle 2 'y of the priming armature (9) and that the difference of these angles PY is smaller than the angle 2c that the priming armature (9) forms with its starting position after initial acceleration by the load priming (8).   9 Device according to claim 4 characterized in that the opening angle 2 3 of the explosive charge 3 is greater than the opening angle 2 Y of the armature   of initiation (9) and that the difference of these angles PY is equal to the angle 2 of which the priming armature (9) forms with its initial position after initial acceleration by the amorph charging charge (8) .   Device according to Claim 4, characterized in that the opening angle 2 of the explosive charge E 547909   * 15 (3) is larger than the opening angle 2 Y of the priming armature (9) and the difference of these angles pY is larger than the angle 2 C that the armature of priming (9) forms with its starting position after initial acceleration by the priming charge (8).