GB2172971A

GB2172971A - A striker and detonator assembly for priming exploding charges

Info

Publication number: GB2172971A
Application number: GB8605269A
Authority: GB
Inventors: Renzo Leveratto
Original assignee: MISAR SpA
Current assignee: MISAR SpA
Priority date: 1985-03-06
Filing date: 1986-03-04
Publication date: 1986-10-01
Also published as: PT82108B; ES552646A0; IT8521014V0; PT82108A; GB2172971B; GR860552B; ES8701978A1; GB8605269D0

Abstract

A striker and detonator assembly for priming exploding charges, in particular for mines, provides fully safe conditions with the detonator inserted and the striker positioned along its line of action. The detonator (5) is rotatable between alignment and misalignment positions to the striker 2 by means of a sprocket 3 which rotates in response to an external impulse and engages a toothed detonator container 7. A safety wall 8 between the detonator 5 and the exploding charge 12 has a thin section 8a adapted to be pierced by the detonator 5 blast in the aligned position. <IMAGE>

Description

SPECIFICATION A striker and detonator assembly for priming exploding charges This invention relates to a striker and detonator assembly for priming exploding charges, in particular for mines.

As is known, generic exploding charges, and specifically mines, have in many cases a striker which is always positioned along its line of action, a detonator or be activated by said striker and in turn effective to prime an exploding charge, and a series of control elements which are closely connected to the striker to drive its projection.

In the instance of local action anti-personnel mines of the SB-33 type, as made by this same Applicant, said control elements connected to the striker mainly comprise a mushroom-like member connected to the top or cap of the mine which, on application of a pressure to the mine top, is moved to forcibly rotate a ring-like element or sprocket, which on completion of its rotation releases the striker allowing it to be projected against the detonator.

In any situations, the striker would be positioned along its line of action, intersecting the detonator.

This prior mechanism is specially functional, from the standpoint of its effectiveness, but requires, for safe handling, that the detonator be inserted only at the last moment. This for two distinct reasons: alignment of the striker and detonator, as constantly maintained, is inherently dangerous, and incidental causes may lead to the detonator being fired even with no impulse from the striker, thus priming the exploding charge. The latter situation is specially objectionable because it forbids storage of the mines with the detonator installed even if the safety devices provided to prevent incidental projection of the striker are intrinsecally satisfactory and safe.

This negative situation also reflects on transport, as well as storage, requirements and on the mine laying procedures, since serious accidents may occur in view also of the large number of mines which are handled during mine laying.

In view of the above situation, it is a general object of this invention to provide a striker and detonator assembly which can substantially obviate such drawbacks.

This object is substantially achieved by a striker and detonator assembly for priming exploding charges, of a type having a striker positioned at all times along its line of action, a detonator placed along said line of action, and control elements effective to cause said striker to be projected and including a ring-like element rotatable by an external impulse, characterised in that said detonator is inserted into a through cavity in a rotatable containment element, on command from said ring-like element, between a position where said striker and detonator are out of alignment and a position where they are aligned, and in that a safety wall is provided between said containment element and an exploding charge to be primed by said detonator, said safety wall having, at said line of action of said striker, a thin pierceable section for firing said detonator.

Further features will become apparent from the following detailed description of a striker and detonator assembly, with reference to the accompanying drawings, where: Figure 1 shows the assembly of this invention in the safe or sear position thereof; and Figure 2 shows the same assembly as in Fig. 1, in the firing position thereof.

With reference to the drawing figures, an assembly according to this invention is comprehensively designated 1. It is provided, as an example, for use in devices known per se and manufactured by this same Applicant under the trade name of SB-33. These devices define local action anti-personnel mines.

The assembly 1 comprises, in a manner known per se, a striker 2 connected to control elements including, as described above, a ring-like element or sprocket 3 rotatable on command from a mushroom member movable linearly by an external impulse, e.g. on stepping on the mine top. Located adjacent to the striker 2, along the line of action 4 thereof, is a detonator 5 of the one-way type which is peculiarly inserted into a through cavity 6 formed in a containment element 7 defined by a small pinion. The containment element 7 is surrounded by a safety wall 8 of non-uniform thickness.

Said safety wall 8 forms in practice a small block wherein a circular cavity 9 is formed which accomodates the containment element 7 rotatably therein. The circular cavity 9 is located offcentered in said block so as to define, along the line of action 2a of the striker 2, a thin section 8a to be pierced through by the blast of the detonator 5, with the latter aligned to the striker 2, as shown in Fig. 2.

The remaining portions of the safety wall 8 are made much thicker than the thin section 8a, thereby they cannot be pierced by incidental blasting of the detonator 5.

The containment element 7 is rotatable on command from the ring-like element 3, from a position where the striker 2 and detonator 5 are out of alignment to each other (Fig. 1) to a position where they are aligned to each other (Fig. 2). It is envisaged that the axis of the through cavity 6 whereinto the detonator 5 is inserted can rotate, between said positions, through an angle of say 90 , preferably slightly larger than 90".

The sprocket 3 rotation will be transmitted to the containment element 7 from the ringlike element 3 via first teeth 10 formed on the ring-like element and second teeth 11 formed on the containment element 7. It is further envisaged that the teeth 10 and 11 engage with limited peripheral sections of said elements 3 and 8.

At one end of the first teeth 10 there is provided a first enlarged tooth 10a adapted to hold the containment element 7 with the detonator 5 in the aligned position to the striker 2 even before the ring-like element 3 completes its rotation (Fig. 2). A second enlarged tooth 1 orb is located at the other end of the first teeth 10 for inhibiting rotation between the elements 3 and 7.

It should be lastly pointed out that the safety wall 8 is surrounded by an exploding charge 12, to be primed by firing the detonator 5.

The assembly of this invention operates as follows.

On applying a pressure to the mine top, a chain of actions take place which result, in a manner known per se, in the ring-like element or sprocket 3 being rotated. According to the invention, this results in the containment element 7 being rotated and the detonator 5 being aligned to the striker 2. The rotation of the containment element 7 can be advanced with respect to the striker 2 firing, by virtue of the first enlarged tooth 10a, to make sure that the detonator 5 is aligned to the striker 2. On firing the striker 2, whose projection is enabled on the ring-like element 3 reaching the end of its rotary travel, the detonator 5 will explode and pierce the safety wall 8, since it acts on a thin section 8a of the safety wall 8.

When the detonator 5 explodes due to incidental causes while not aligned to the striker 2, the blast will impinge on a specially thick section of the safety wall 8, and accordingly, be unable to pierce it and prime the exploding charge 12.

The invention affords important advantages.

In fact, it allows the mines to be transported and laid in complete safety, since the detonator is not aligned to the striker, and above all, incidental firing cannot prime the exploding charge.

Alignment of the detonator to the striker only takes place at the time when the mine, under the action of a weight, brings the striker to firing, thereby it becomes possible to arrange magazines loaded with mines, preparatory to mine laying, which would be always ready for use since the mines do not require to be disassembled for inserting the detonators thereinto.

Claims

1. A striker and detonator assembly for priming exploding charges, of a type having a striker positioned at all times along its line of action, a detonator placed along said line of action, and control elements effective to cause said striker to be projected and including a ring-like element rotatable by an external impulse, characterised in that said detonator is inserted into a through cavity in a rotatable containment element on command from said ring-like element, between a position where said striker and detonator are out of alignment and a position where they are aligned, and in that a safety wall is provided between said containment element and an exploding charge to be primed by said detonator, said safety wall having, at said line of action of said striker, a thin pierceable section for firing said detonator.

2. An assembly according to claim 1, characterised in that said containment element is a small pinion, and in that first and second sets of teeth in mutual mesh engagement are formed on said ring-like element and said containment element respectively.

3. An assembly according to claim 2, characterised in that said first and second sets teeth engage with limited peripheral sections of said ring-like element and said containment element, and in that at the ends of said first set of teeth there are provided enlarged teeth adapted, on the one hand, to hold said detonator at a position of alignment to said striker, prior to projecting the latter, and on the other hand to inhibit rotation.

4. An assembly according to any preceding claim, characterised in that said safety wall is substantially defined by a small block wherein there is formed, at an offcentre position, a circular cavity wherein said containment element is inserted rotatably.

5. An assembly according to any preceding claim, characterised in that said containment element rotates, between said misaligned and aligned positions, through substantially at least 90".

6. A striker and detonator assembly for priming exploding charges, substantially as herein described with reference to the accompanying drawings.