EP1524489B1 - Ignition device and multi-mode shaped charge which uses such an ignition device - Google Patents

Abstract

The device has an explosive relay sheet (6a) that is arranged between an ignition cap (3) and a detonation relay, where the cap initiates the sheet. A mobile plate (8) supporting an intermediary relay (9a) occupies two positions. The intermediary relay is arranged opposite to a hole in one position of the plate. The relay (9a) is arranged between the sheet and the denotation relay in the other plate position.

Description

The technical field of the invention is that of devices for the initiation of an explosive charge and in particular that of devices for initiating a multi-mode shaped charge.

Priming devices are known in which a detonator is secured to a movable plate for aligning it with a detonation relay itself initiating an explosive charge.

US 4784062 discloses such a device and forms the basis of the independent claim.

Depending on the position of the plate, the detonator can thus occupy a misaligned position (in which it can not initiate the explosive charge) and an aligned position in which initiation is possible.

The detonator is most often controlled by a firing rocket to which it is connected by a wired link.

These devices are complex because it is necessary to provide son lengths sufficient for the movement of the detonator, the wire should not interfere with the movements of the plate.

This constraint provided by the wired link is amplified when the priming device comprises several detonators.

US5939663 discloses a multi-mode charge that can be initiated selectively by a priming comprising an axial detonator and a ring of peripheral detonators.

All the detonators are connected to initiation means by separate wire connections.

Depending on the detonators that are ordered we get a coherent stream or a projection of splinters.

In addition to the complexity of the integration of the wired links, this load and the boot device that it comprises also have the disadvantage of requiring the control of the precise synchronization of the initiation orders.

It is the object of the invention to provide a priming device for overcoming such disadvantages.

Thus the priming device according to the invention allows, by acting on the position of a control plate, to ensure or not the initiation of an explosive charge. Moreover it implements only one fixed detonator which simplifies the electrical connections.

The device according to the invention also makes it possible, in a reliable and simple manner, to provide various types of multi-point priming from a single detonator.

Thus, the subject of the invention is a priming device comprising a detonator and at least one detonation relay, characterized in that it comprises, arranged between the detonator and the detonation relay or relays, on the one hand at least a transmission explosive sheet comprising at least one hole, and secondly at least one movable plate carrying at least one intermediate relay of diameter smaller than that of the hole, the relay explosive sheet being arranged so as to be initiated by the detonator, the mobile stage being able to occupy at least two positions, a first position or inactivated position in which the intermediate relay is arranged opposite the hole and a second position or ignition position in which the intermediate relay is located between the sheet of explosive transmission and a detonation relay.

According to a particular embodiment of the invention, the movable stage is a pivoting circular stage carrying at least three intermediate relays uniformly angularly distributed and intended to be positioned either facing holes carried by the transmission sheet or opposite relay relays. detonation.

Advantageously, the mobile stage may comprise a ring of intermediate relays disposed in the vicinity of its outer periphery, so-called peripheral relays.

Advantageously, the mobile stage may also include at least three other intermediate relays (or median relays) arranged at a substantially middle circle of the plate, the device further comprising a second sheet of transmission explosive disposed between the median relays platinum and an axial detonation relay, the median relays can also be positioned opposite holes carried by the first sheet of transmission explosive.

• une première position dans laquelle le détonateur est relié uniquement à des relais de détonation externes par l'intermédiaire de la première feuille d'explosif de transmission ainsi que par les relais périphériques de la platine, les relais médians de la platine étant alors positionnés en regard de trous médians portés par la première feuille,
• une deuxième position dans laquelle le détonateur est relié uniquement au relais de détonation axial par l'intermédiaire des relais médians de la platine ainsi que par les deux feuilles d'explosif de transmission, les relais périphériques de la platine étant alors positionnés en regard de trous périphériques portés par la première feuille,
• une troisième position dans laquelle le détonateur est relié à la fois au relais de détonation axial et aux relais de détonation externes par l'intermédiaire des relais de la platine et des deux feuilles d'explosif de transmission.

The angular positions of the peripheral and median holes of the first sheet of transmission explosive as well as those of the peripheral and median relays carried by the plate will preferably be chosen so that the turntable can occupy at least three different angular positions:

• a first position in which the detonator is connected only to external detonation relays via the first sheet of transmission explosive as well as by the peripheral relays of the plate, the median relays of the plate being then positioned opposite of median holes carried by the first leaf,
• a second position in which the detonator is connected only to the axial detonation relay via the middle relays of the plate as well as by the two sheets of transmission explosive, the peripheral relays of the plate being then positioned opposite holes devices carried by the first leaf,
• a third position in which the detonator is connected to both the axial detonation relay and the external detonation relays via the platen relays and the two transmission explosive sheets.

The median relays of the platen may be arranged at a circle whose diameter will be substantially half the diameter of the circle at which will be arranged the peripheral relays of the plate.

The movable stage may be movable by a motor means actuated by a control means.

The motor means may comprise a screw or pinion meshing with a toothed portion of the plate.

The invention also relates to a multi-mode shaped charge incorporating such a priming device.

The multi-mode shaped charge according to the invention comprises a coating and an explosive charge interposed between the coating and the priming device, this charge characterized in that it can be initiated according to at least two different modes: either by an axial detonation relay or by a ring of external detonation relays, the choice of one or the other of the operating modes being obtained by controlling the pivoting of a plate of the ignition device carrying intermediate relays.

Advantageously, the multi-mode shaped charge can be initiated according to at least three different modes: by an axial detonation relay, by a ring of external detonation relays, or by the simultaneous initiation of the axial relay and the external detonation relay ring. , the choice of the operating mode being obtained by controlling the pivoting of the plate.

• la figure 1 représente un dispositif d'amorçage suivant un premier mode de réalisation de l'invention, dispositif représentée en position inactivée,
• la figure 2 représente ce même dispositif d'amorçage dans sa position d'amorçage,
• la figure 3 est une vue en coupe longitudinale d'une charge formée équipée d'un dispositif d'amorçage suivant un deuxième mode de réalisation,
• la figure 4a représente en coupe le dispositif d'amorçage de cette charge, seul et dans sa première position, le dispositif est coupé suivant le plan dont la trace BB est repérée à la figure 4b,
• la figure 4b représente, avec une découpe partielle de la feuille d'explosif de transmission, le dispositif dans sa première position et coupé suivant le plan dont la trace AA est repérée à la figure 4a,
• la figure 4c est une autre vue en coupe du dispositif d'amorçage coupé suivant le plan dont la trace XX est repérée à la figure 4b,
• la figure 5a représente en coupe le dispositif d'amorçage de cette charge, seul et dans sa deuxième position, le dispositif est coupé suivant le plan dont la trace DD est repérée à la figure 5b,
• la figure 5b représente, avec une découpe partielle de la feuille d'explosif de transmission, le dispositif dans sa deuxième position et coupé suivant le plan dont la trace CC est repérée à la figure 5a,
• la figure 5c est une autre vue en coupe du dispositif d'amorçage coupé suivant le plan dont la trace YY est repérée à la figure 5b,
• la figure 6a représente en coupe le dispositif d'amorçage de cette charge, seul et dans sa deuxième position, le dispositif est coupé suivant le plan dont la trace FF est repérée à la figure 6b,
• la figure 6b représente, avec une découpe partielle de la feuille d'explosif de transmission, le dispositif dans sa deuxième position et coupé suivant le plan dont la trace EE est repérée à la figure 6a,
• les figures 6c et 6d sont deux autres vues en coupe du dispositif d'amorçage coupé suivant les plans dont les traces sont repérées respectivement ZZ et WW sur la figure 6b,
• la figure 7 est une vue en perspective externe du dispositif d'amorçage suivant le deuxième mode de réalisation de l'invention, vue permettant de visualiser un exemple de mise en place d'un moteur de commande du pivotement de la platine.

The invention will be better understood on reading the following description of various embodiments, a description given with reference to the appended figures and in which:

• FIG. 1 represents a priming device according to a first embodiment of the invention, device represented in an inactivated position,
• FIG. 2 represents this same priming device in its starting position,
• FIG. 3 is a longitudinal sectional view of a shaped charge equipped with a starting device according to a second embodiment,
• FIG. 4a represents in section the device for priming this load, alone and in its first position, the device is cut along the plane whose trace BB is marked in FIG. 4b,
• FIG. 4b represents, with a partial cut of the transmission explosive sheet, the device in its first position and cut along the plane whose track AA is marked in FIG. 4a,
• FIG. 4c is another sectional view of the ignition device cut along the plane whose trace XX is marked in FIG. 4b,
• FIG. 5a represents in section the device for priming this load, alone and in its second position, the device is cut along the plane whose trace DD is marked in FIG. 5b,
• FIG. 5b represents, with a partial cut of the transmission explosive sheet, the device in its second position and cut along the plane whose trace CC is marked in FIG. 5a,
• FIG. 5c is another sectional view of the ignition device cut along the plane whose trace YY is marked in FIG. 5b,
• FIG. 6a represents in section the device for priming this load, alone and in its second position, the device is cut along the plane whose trace FF is marked in FIG. 6b,
• FIG. 6b shows, with a partial cut of the transmission explosive sheet, the device in its second position and cut along the plane whose trace EE is marked in FIG. 6a,
• FIGS. 6c and 6d are two other sectional views of the ignition device cut along the planes whose traces are respectively labeled ZZ and WW in FIG. 6b,
• Figure 7 is an external perspective view of the priming device according to the second embodiment of the invention, view for viewing an example of setting up a control motor of the pivoting of the plate.

Referring to Figures 1 and 2, a priming device 1 according to a first embodiment of the invention comprises a housing 2 whose upper face carries a detonator 3 which is connected by connections not shown to a setting device. fire (not shown).

The housing 2 is closed by a cover 4 which carries a detonation relay 5. The latter is disposed opposite an explosive charge (not shown) that it is responsible for initiating.

According to the invention, the device 1 comprises a transmission explosive sheet 6 which is disposed at the bottom of the housing 2 facing the detonator 3.

This sheet is made for example of a plastic explosive based on rubber and pentrite (explosive known under the trademark Formex) and carries a hole 7. It is fixed to the housing 2 for example by gluing.

The device according to the invention also comprises a movable plate 8 which carries an intermediate pyrotechnic relay 9 whose diameter is chosen to be smaller than that of the hole 7. This relay may consist of a Hexocire tablet.

The plate 8 can be moved by the action of a motor means which is here a compression spring 10 disposed between a flange of the plate 8 and an inner surface of the housing 2. In the position shown in Figure 1, this spring is held compressed by a lock 11 carried by the cover 4. The rod 12 of the lock enters a housing of the plate 8 and immobilizes it with respect to the lid 4. The latch 11 may be constituted by a small electromagnet.

When the device 1 is in the inactivated position shown in Figure 1, the firing of the detonator 3 leads to the initiation of the transmission explosive sheet 6. Due to the presence of the hole 7 next to the relay intermediate 9 the latter is not initiated. The detonation relay 5 is also opposite the plate 8 which plays the role of screen. He is not himself initiated.

When the latch 11 is activated, the plate 8 is released. It is pushed by the spring 10 and takes the ignition position shown in Figure 2 (position in which the plate can be blocked by a not shown locking means).

In this position, the intermediate relay 9 is positioned between the transmission explosive sheet 6 and the detonation relay 5.

The firing of the detonator 3 then leads to the initiation of the transmission explosive sheet 6 which initiates the intermediate relay 9. The latter then initiates the detonation relay 5 which causes the ignition of the explosive charge (not shown ).

This device thus makes it possible to obtain in a simple way the activation or the deactivation of a priming.

It is thus possible to give the relay explosive sheet various shapes and dimensions, this sheet propagates at any point on its lower face a detonation wave which is communicated to it by the detonator primer positioned at its upper face. One or more holes on this sheet will define areas at which there will be no detonation wave transmission.

It is therefore sufficient to inactivate a detonation relay to position it opposite one of the holes. On the other hand, when this relay is positioned opposite any other part of the sheet, it can be activated by the detonator primer.

The device according to the invention is more particularly advantageous for performing multi-point firing for multimode shaped charges.

FIG. 3 thus shows a shaped charge 13 which conventionally comprises an explosive charge 15 disposed in an envelope 16. A concave coating 14 is applied to the explosive charge 15.

A priming device 1 according to a second embodiment of the invention is attached to the casing 16 by means not shown.

This charge can be initiated according to at least two different modes. It can be initiated by an axial detonation relay 17 or by a ring of external detonation relays 18.

It is thus well known (especially patent EP1164348) that, when such a load is initiated axially, the projection of the coating is obtained in the form of an elongated core whereas, when the load is initiated by the crown of peripheral relays, the coating is sprayed in the form of an animated jet with a high speed (greater than 3000 m / s).

If, on the other hand, the relays 19 of the outer ring gear and the axial relay 17 are simultaneously initiated, the interactions between the different shock waves cause dislocation of the coating in the form of splinters.

The concavity of the coating is defined by the skilled person to allow operation of the load in several modes. This geometry is not the subject of the present invention and it is therefore unnecessary to specify it further. We can refer to the patent EP1164348 which describes a possible type of coating.

The priming device according to the invention makes it easy to obtain one or the other of the operating modes from the initiation of a single detonator primer 3.

The choice of mode will be obtained by the pivoting of a movable turntable 8, pivoting controlled by a small motor driving a worm 19 meshing with a peripheral sector 20 of the plate 8 (see Figure 4b). The motor is not shown in Figures 3 to 6 to not impair their clarity. FIG. 7 shows a possible location of a motor 22 driving a toothed sector 22a meshing with the screw 19.

FIGS. 4a, 4b and 4c show in a more precise manner the structure of this device 1.

The cover 4 which closes the housing 2 carries an axial detonation relay 17 and a ring of external detonation relays 18. These relays are in contact with the explosive charge 15 of the shaped charge 13 (see FIG. 3).

As in the previous embodiment, a transmission explosive sheet 6a is disposed at the bottom of the housing 2 facing the detonator 3. This sheet is glued to the housing 2. The detonator 3 is connected to a non-firing device represent.

In this particular embodiment, the lid 4 carries a circular bowl inside which is placed a second sheet 6b of transmission explosive, sheet having the same composition as the first sheet 6a and which is glued to the lid 4.

The diameter of this second sheet 6b is substantially equal to half the diameter of the first sheet 6a.

Furthermore, the plate 8 is circular and bears against an inner circular shoulder 21 of the housing 2. This provision is intended to prevent friction between the plate 8 and the relay sheet 6a during pivoting of the plate.

This turntable 8 carries a ring of intermediate relays 9a regularly distributed angularly (here twenty four relays) arranged near its outer periphery.

These relays will be said peripherals and they are intended to be positioned either opposite peripheral holes 7a carried by the first transmission sheet 6a, or opposite external detonation relays 18.

According to this embodiment of the invention, the turntable 8 also carries four other intermediate relays 9b (called median relays) which are arranged at a substantially median circle of the plate 8.

These median relays 9b are arranged facing the second transmission explosive sheet 6b. Depending on the angular positioning of the plate 8, they can be positioned or not facing holes 7b carried by the first transmission relay sheet 6a.

As is more particularly visible in FIG. 4b, the first transmission explosive sheet 6a thus carries twenty four peripheral holes 7a and four median holes 7b angularly arranged at 90 ° from each other. The medial holes 7b are angularly on diameters which also pass through peripheral holes 7a. In FIG. 4b, the transmission explosive sheet 6a is partially cut on its left side (section line L) so as to show the plate 8, a few peripheral relays 9a and a median relay 9b. By convention, in FIG. 4b as well as in FIGS. 5b and 6b, the relays 9a and 9b of the plate 8 are shown in black when they are visible in the figure and in gray when they are hidden by the explosive sheet 6a.

The turntable 8 thus carries twenty four peripheral relays 9a and four median relays 9b.

However, as regards the plate 8, the median relays 9b are angularly on diameters which are offset with respect to the diameters carrying the peripheral relays 9a.

Thus, as shown in FIG. 4b, a median relay 9b is located on a diameter D3 which bisects the diameters D1 and D2 passing through two consecutive peripheral relays 9a.

With a device as shown in the figures and which comprises twenty-four peripheral relays, two neighboring peripheral relays 9a are therefore separated by an angle α = 15 °.

Thus a 15 ° pivoting of the plate 8 places it in an identical position from the point of view of the relative positioning of the peripheral relays 9a and the external detonation relays 18.

The median relays 9b are separated by 90 ° from each other and the diameters D3 of the plate passing through these median relays 9b form an angle equal to α / 2 = 7.5 ° with two consecutive diameters D1, D2 passing through two relays consecutive peripherals 9a (see Figure 4b).

Such an arrangement allows, in an extremely simple manner, by the simple pivoting of the plate 8, to obtain several different modes of ignition.

Thus FIGS. 4a, 4b and 4c represent the device in a first position in which the detonator 3 only controls the initiation of external detonation relays 18.

Indeed, when the detonator 3 is initiated, it in turn initiates the first sheet of transmission explosive 6a. The latter is next to the peripheral relays 9a of the plate 8. These twenty four relays are initiated simultaneously. The simultaneity of initiation results from the circular propagation of the detonation wave through the first sheet of transmission explosive 6a from the detonator 3.

In this first position, the first transmission explosive sheet 6a does not initiate the median relays 9b of the plate 8, the latter being positioned opposite the medial holes 7b carried by the first sheet 6a.

The second sheet 6b of transmission explosive is therefore not initiated and the axial detonation relay 17 either.

This results in an initiation of the explosive charge 15 of the formed charge 13 along a ring. This initiation leads to the formation of a jet.

Figures 5a, 5b and 5c show the device according to the invention in its second position.

The plate 8 has been pivoted by 7.5 ° by the action of the motor on the screw 19 and thus on the toothed portion 20 of the plate 8.

In this position the peripheral relays 9a of the plate 8 are all positioned opposite the peripheral holes 7a carried by the first sheet 6a.

The latter can not initiate the peripheral relay 9a.

In this second position of the device the median relays 9b are no longer opposite the holes 7b but well arranged between the two sheets of transmission explosive 6a and 6b.

The firing of the detonator 3 then leads to the initiation of the axial detonation relay 17 alone via the median relay 9b of the plate and by the two sheets of transmission explosive 6a and 6b.

The explosive charge 15 of the formed charge 13 is then initiated axially. This initiation leads to the formation of a nucleus.

Figures 6a, 6b, 6c and 6d show the device according to the invention in its third position.

With respect to the second position, the plate 8 was further rotated by 7.5 ° by the action of the motor on the screw 19 therefore on the toothed portion 20. The total pivoting is therefore 15 ° relative to the first position shown in Figures 4a, 4b, 4c.

In this position all the relays of the plate 8 (median relays 9b and peripheral relay 9a) are initiated by the first sheet of transmission explosive 6a.

The firing of the detonator 3 thus leads to the initiation of all twenty four external detonation relays 18 and to that of the axial detonation relay 17.

The peripheral initiations and the axial initiation are practically simultaneous. Indeed the median relays 9b of the plate 8 are arranged at a circle whose diameter is substantially half the diameter of the circle at which the peripheral relays 9a are arranged.

The time required for the detonation wave to reach the peripheral relays 9a is therefore practically equal to the sum of the time required for this wave to reach the median relays 9b and the time required for the detonation wave to traverse the second sheet radially. transmission explosive 6b (the explosives used for the two sheets being the same).

The skilled person may adjust the desired delay between the initiation of the peripheral relay 18 and that of the axial relay 17 by varying the diameter of the circle of the plate 8 carrying the median relays 9b with respect to the diameter of the circle carrying the relays 9a devices. It may also play on the detonation characteristics of each sheet of transmission explosive 6a, 6b.

This simultaneous or near-simultaneous initiation at the periphery and in the axis leads to detonation wave compositions within the explosive charge 15 of the formed charge 13 which lead to fragmentation of the coating 14 into fragments.

It would of course be possible to define a device according to the invention whose plate would carry a different number of relays, both periphery and middle zone.

One could also define a priming device according to the invention comprising more than three modes of operation, for example by providing another relay ring integral with the plate.

The motor means for pivoting the plate could be of different structure. One could also use a piezoelectric actuator advancing the plate by a desired angle through a snap.

One could of course make a device in which the sheets of transmission explosives 6a and / or 6b would have non-circular shapes. For example rectangular sheets or bands of explosives.

Claims (10)

1. A priming device (1) incorporating a detonator (3) and at least one detonation relay (5), such device characterised in that it comprises, positioned between the detonator (3) and the detonation relay or relays (5), firstly at least one transmission explosive sheet (6, 6a) incorporating at least one hole (7, 7a, 7b), and secondly at least one mobile plate (8) carrying at least one intermediate relay (9, 9a, 9b) of a diameter less than that of the hole (7, 7a, 7b), the relay explosive sheet (6, 6a) being arranged so as to be ignited by the detonator (3), the mobile plate (8) being able to occupy at least two positions, a first position, or inactive position, in which the intermediate relay (9, 9a, 9b) is positioned opposite the hole (7, 7a, 7b) and a second position, or priming, position in which the intermediate relay (9, 9a, 9b) lies between the transmission explosive sheet (6, 6a) and a detonation relay (5, 17, 18).
2. A device according to Claim 1, characterised in that the mobile plate (8) is a circular pivoting plate carrying at least three intermediate relays (9a) evenly spaced angularly and intended to be positioned either opposite the holes (7a) in the transmission sheet (6a) or opposite the detonation relays (18).
3. A device according to Claim 2, characterised in that the mobile plate (8) incorporates a crown of intermediate relays (9a) positioned in the vicinity of its external periphery, so-called peripheral relays.
4. A device according to Claim 3, characterised in that the mobile plate (8) incorporates at least three other intermediate relays (9b) (or median relays) arranged in a substantially median circle of the plate (8), the device incorporating furthermore a second transmission explosive sheet (6b) arranged between the median relays (9b) and the plate and an axial detonation relay (17), the median relays (9b) also being able to be positioned opposite holes (7b) in the first transmission explosive sheet (6a).
5. A device according to Claim 4, characterised in that the angular positions of the peripheral (7a) and median (7b) holes in the first transmission explosive sheet (6a) as well as those of the peripheral (9a) and median (9b) relays carried by the plate (8) are selected such that the pivoting plate (8) is able to occupy at least three different angular positions:

   - a first position in which the detonator (3) is linked solely to external detonation relays (18) by means of the first transmission explosive sheet (6a) as well as by the peripheral relays (9a) of the plate (8), the median relays (9b) of the plate being in this case positioned opposite the median holes (7b) carried by the first sheet (6a),

   - a second position in which the detonator (3) is linked solely to the axial detonation relay (17) by means of the median relays (9b) of the plate (8) as well as by the two transmission explosive sheets (6a, 6b), the peripheral relays (9a) of the plate (8) being in this case positioned opposite to peripheral holes (7a) in the first sheet (6a),

   - a third position in which the detonator (3) is linked both to the axial detonation relay (17) and to the external detonation relays (18) by means of the relays (9a, 9b) of the plate (8) and the two sheets of transmission explosive (6a, 6b).
6. A device according to one of Claims 4 or 5, characterised in that the median relays (9b) of the plate (8) are arranged in a circle whose diameter is substantially half that of the circle in which the peripheral relays (9a) of the plate (8) are arranged.
7. A device according to one of Claims 1 to 6, characterised in that the mobile plate (8) is displaced by motor means (19, 22) activated by control means.
8. A device according to Claim 7, characterised in that the motor means comprise a screw (19) or pinion meshing on a toothed portion (20) of the plate (8).
9. A multi-mode shaped charge (13) incorporating a priming device (1) according to one of Claims 4 to 6 as well as a liner (14) and an explosive charge (15) positioned between the liner (14) and the priming device (1), charge characterised in that it is ignited according to at least two different modes: either by an axial detonation relay (17) or by a crown of external detonation relays (18), the selection of one or other modes of functioning being made by activating the pivoting of a plate (8) in the priming device which carries intermediate relays (9a, 9b).
10. A multi-mode shaped charge according to Claim 9, characterised in that it can be ignited according to at least three different modes: by an axial detonation relay (17), by a crown of external detonation relays (18), or by the simultaneous ignition of the axial relay (17) and the crown of external detonation relays (18), the selection of the mode of functioning being obtained by activating the pivoting of the plate (8).

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