FR2643982A1 - HOLDING DEVICE FOR PROJECTILE IGNITER - Google Patents

Abstract

The retainer of a projectile igniter is designed to cause ignition of the projectile only when it has passed through a barrier. The point in time of ignition depends on the impact velocity of the projectile and the deceleration exerted by the barrier on the projectile. To this end, an element movable transversely to the direction of flight and subjected to the stress of a spring is stopped by a release member 5 movable in the direction F of the flight. The deceleration of the projectile following its passage through the barrier brings the release member 5 into a position where it releases the transversely movable element 2. When the deceleration is completed, the transversely movable element is in a position of 'ignition.

Description

The invention relates to a retaining device for a projectile igniter.

  retainer for a projectile igniter, which initiates the ignition of a projectile after passing through

a barrier.

  A retaining device of this type is used in ammunition which must have passed through a barrier before ignition, such as a covering roof or a wall. According to the state of the art, pyrotechnic charges with delay or electronic delay circuits are used as a retaining device, which are initiated by the impact on the barrier and cause the ignition after a determined time. The disadvantage is that the ignition takes place after a fixed duration which does not take into account the speed of the projectile and the way in which the barrier is constituted. The

  projectile then explodes too soon or too late.

  A retaining device described in document DE-A 34 18 759, works with a retaining element movable transversely to the direction of flight. But this restraint is not suitable for

  initiate ignition of the projectile after it has crossed a barrier.

  The object of the invention is to propose a retaining device of the type mentioned in the preamble, in which the point in time of ignition depends on the impact speed of the projectile and on the extent of the deceleration that the barrier exerts on the projectile. - 2 - According to the invention, the above object is achieved by means of a retaining device of the type mentioned in the preamble because an element subjected to the stress of a spring and movable transversely to the direction of the flight is stopped in a stopped position by a release member movable in the direction of flight, and the fact that following the crossing of the barrier, the deceleration of the projectile which takes place brings the release member into a position in which it releases the transversely movable element, and the fact that during or at the end of deceleration the element transversely

  mobile reaches an ignition position.

  If the deceleration lasts for a relatively long period owing to the fact that it is a strong barrier and / or that the impact speed of the projectile on the barrier is low, the ignition then takes place later after the impact than in the opposite case in which the barrier is less resistant and / or the speed of impact of the projectile is high. This prevents the projectile from bursting as it crosses the barrier. Ignition only takes place when the flight of the projectile through the barrier is no longer braked, i.e.

  decelerated, and the projectile passed through the barrier.

  According to one embodiment of the invention, the transversely movable element is held by friction on a guide element as a result of the deceleration of the projectile and triggers

  ignition at the end of deceleration.

  According to another embodiment of the invention, the transversely mobile element releases the release member in the ignition position so that the latter triggers the ignition when the

deceleration is complete.

  Advantageously, a detonator is mounted in the transversely movable element and the latter sends the detonator into an ignition rod when its transverse movement is complete and

triggers its ignition.

  The transversely movable element comprises a periphery against which abuts the release member and this release member

  leaves the edge during deceleration.

  According to the invention, the transversely movable element consists of 3- a rotor or a slide that releases the acceleration at the time of firing. This transversely movable element is brought into the ignition position of the release member so that the latter initiates ignition when the deceleration is complete. The transversely mobile element advantageously comprises a first bore into which the release member enters before deceleration and thus maintains the transversely mobile element in

its blocking position.

  The transversely movable element may include another bore through which the release member passes and which is arranged in the ignition position of the transversely movable element on the

  course followed by the liberation body.

  Finally, the invention provides that a compression spring

  moves the release member after deceleration.

  The invention will now be described in more detail using embodiments and with reference to the accompanying drawings in which: FIG. 1 schematically represents a first embodiment of the invention, FIG. 2 represents a variant of the first embodiment, Figure 3 in Figure 6 schematically show a second embodiment of the device of the invention in its various

operating positions.

  In a igniter 1 of a projectile is mounted a slide 2 constituting a transversely movable element. It is possible to provide a rotor in place of the slider 2. The slider 2 is mounted movably in the igniter 1 by a guide element 3 in the direction transverse R to the direction F of the flight of the projectile. The slider 2 is subjected to the stress of a compression spring 4. With the slider 2 is associated a release member 5 movable in the direction of flight F and resting against a step 7 of the slider 2 under the effect of a spring of compression 6. To the step 7 is connected a

other tier 8.

  -4- Before firing the projectile, the slider 2 is stopped by a locking member 9. In the slider 2 is mounted a detonator 10 which can be brought into a first ignition chain 11 and into a second ignition chain 12 The first ignition switch 11 can be switched on by a distance detector. A second ignition switch 12 is associated with a striker 13 which can be released by the

  slide 2 and by a trigger element 14.

  The operating mode of the device described according to Figure 1

is substantially the following.

  When firing the projectile, the blocking member 9 releases the slider 2 and the latter is moved in the direction R by the compression spring 4 until the release member 5 abuts against the body 15 of the step 7. The detonator 10 is then in the first ignition chain 11. If a remote ignition is desired, the distance detector then responds to an appropriate distance. When the projectile hits a barrier, it is braked. The release member 5 then moves by its inertia against the force of the compression spring 6 in the direction of flight F. It remains for the duration of the deceleration at the level of the step 8. During this deceleration, the slide 2 is pressed against the guide element 3 and it is held against the latter by friction. When the barrier has been pierced, the deceleration ends and the slide continues to be moved in the direction R by the compression spring 4 until the release member 5 abuts against the edge 16 of the step 8. The detonator 10 is then located in the ignition chain 12 and the triggering element 14 releases the striker 13. The explosion of the projectile takes place after its

crossing the barrier.

  In the embodiment of Figure 2 is provided a single ignition chain to the plate of two chains. In the slider 2 are arranged in correspondence two detonators 10. An ignition means 17 of the ignition chain can be ignited by a distance detector or after crossing the barrier because the slider

2 closes an electrical contact 18.

  In the embodiment of Figures 3 to 6, the elements

  corresponding to the above description are designated by the same

  references. In Figure 3, the device is shown during the flight phase of the projectile. A rotor 19 contains the detonator 10 and rotates it in the ignition chain 12. A locking member 9 is mounted in the rotor 19 and releases the latter. Before firing, the rotor 19 was blocked in the igniter 1 by the locking member 9. A ball stops the locking member 9 by means of a rod 20. This locking is

  eliminated by accelerating fire.

  During the flight phase (see FIG. 3), the release member 5 is maintained by a pin 22 in a bore 23 of the slider 2, which means that the latter cannot move in the direction R under the effect of the force of the compression spring 4. A ball 24 enters the rotor 19 and it no longer retains the release member preventing it from making a movement in the direction F. Before the rotation of the rotor 19, the ball 24 is located in a cavity 25 of the release member 5, the latter being therefore kept immobile. The release member 5 comprises a larger diameter portion 26 which presses a ball constituting the triggering element

  14 in a cavity 27 of the striker 13.

  When the projectile reaches a barrier, the release member 5 moves under the effect of its inertia against the compression spring 6. The pin 22 then leaves the bore 23 of the slide 2. The striker 13 continues to remain blocked (see Figure 4). During the crossing of the barrier, the slider 2 is pressed in the direction R by the compression spring 4 until another bore 28 of the slider 2 whose diameter is substantially larger than that of the bore 23 has on the course followed

  by the release member 5 (see Figure 5).

  When the projectile has passed through the barrier, the deceleration of the projectile ends, and the compression spring 6 moves the release member 5 in the opposite direction to that of the flight direction F. -6 The release member 5 enters the bore 28 of the slide 2. The larger diameter portion 26 of the release member 5 then leaves the ball 14, and it follows that the striker 13 is released and strikes the ignition means 17 of the chain d ignition 12 under the action of a compression spring 29. The projectile explodes (see

figure 6).

7-

Claims (9)

  1. Retaining device for a projectile igniter, which initiates the ignition of a projectile after having crossed a barrier, characterized in that an element (2) subjected to the stress of a spring and movable transversely to the direction flight is stopped in a stopped position by a release member (5) movable in the direction of flight, in that following the crossing of the barrier the deceleration of the projectile which takes place brings the release (5) in a position in which it releases the transversely mobile element (2), and in that during or at the end of deceleration the transversely mobile element (2) arrives in a ignition position.   2. Retaining device according to claim 1, characterized in that the transversely movable element (2) is held by friction on a guide element (3) and in that at the end of the deceleration of the projectile the element transversely movable (2) triggers ignition.   3. Retaining device according to claim 2, characterized in that a detonator (10) is mounted in the transversely movable element (2) and this transversely movable element (2) sends the detonator (10) in a chain d '' ignition (11, 12) when its movement   transverse is finished and triggers its ignition.   4. Retaining device according to claim 2 or 3, characterized in that the transversely movable element (2) comprises a periphery (15) against which abuts the release member (5), and in that this member release (5) leaves the edge (15) during deceleration.   5. Restraint device according to any one of the claims   2 to 4, characterized in that the transversely movable element is constituted by a rotor or a slide (2) which releases the acceleration when fired.   6. Retaining device according to claim 1, characterized in that the transversely movable element (2) is brought into the ignition position of the release member (5) so that the latter   triggers ignition when deceleration is complete.   - 8- 7. Retaining device according to claim 6, characterized in that the transversely movable element (2) comprises a first bore (23) into which the release member (5) penetrates before deceleration and thus maintains the element transversely mobile (2) in its locking position. 8. Retaining device according to claim 7, characterized in that the transversely movable element (2) comprises another bore (28) which passes through the release member (5) and which is arranged in the ignition position of the transversely movable element (2) on the   course followed by the liberation body (5).   9. Restraint device according to any one of claims   6 to 8, characterized in that the transversely movable element is a slide (2) or a rotor.   O10. Restraint according to any one of   previous claims, characterized in that a spring of   compression (6) moves the release member (5) after deceleration.