AU7777291A - Bullet catcher for stopping bullets - Google Patents

Description

Bullet catcher for stopping bullets

The invention relates to a process for the production of a bullet catcher for stopping bullets and to applications of the bullet catcher produced by the process.

In military combat, a soldier, especially an infantryman, often has to take cover from fire and/or radiation within the shortest possible time. The smallest possible mounds, banks and the like are also used to this end.

If a little more time is available, artificial shelters, especially parapets or manholes with a front parapet, are dug. However, for a simply temporary shelter, this is too troublesome and time-consuming, especially on hard, stony and/or rocky terrain.

Ramparts interspersed with stones moreover have the disadvantage that fellow comrades are put at risk by ricochet shots. Other bullet catchers too, e.g. in a shooting range, are only seldom or only at great expense optimally eguipped with respect to ricochet shots.

DE-C 75836 from the last century describes a bullet catcher comprising a pasty mass arranged in a box. This viscous mass consists of a mixture of, e.g. asphalt, tar, pitch, loam and sand, wherein this mass can be melted down again for removal of the bullets. This bullet catcher is complicated and expensive to manufacture and is only suitable for fixed installations. The bullet catcher described in DE-C 75836 cannot be used for mobile combat.

The object of the invention is to provide a bullet catcher of the type specified initially, which can be produced in a short ti e at little expense, does not cause any ricochet shots, offers good military cover and satisfies the strict safety requirements of a bullet catcher for a shooting range.

With respect to the process, the problem is solved according to the invention in that at least one element comprising an all- round water-permeable tear-resistant cover, which accommodates a cellulose pulp comprising a superabsorber in an expanding closed inner chamber, is arranged at the place where the bullet catcher is to be produced and water is supplied to the swelling elements until saturation thereof, thereby forming a gel, the extensibility of the cover being retained even when the pulp is completely saturated with water. Particular embodiments and developments of the invention are the subject of dependent claims.

Cellulose pulps comprising a so-called superabsorber are generally used in the manufacture of sanitary articles for infants and incontinent adults or for a water-protection device. Dry superabsorbers can take the form of powders or fibres, and upon contact with water they multiply in weight and volume within a very short time, forming a gel-like mass. One kilogram of a superabsorber can absorb up to approximately 600 kg of water, with corresponding expansion. Superabsorbers, also known in abbreviated form as SAP's, are high-absorption polymers, e.g. on the basis of acrylic acid.

It is also known per se that superabsorbers can have a substrate other than a cellulose pulp, e.g. non-woven fabric or the like. For the sake of simplicity, all those variants comprising cellulose pulp or pulp, also of recycling fibres, are indicated which are particularly important on economical and ecological grounds.

A superabsorber completely saturated with moisture, a gel, consists for by far the greater part of water. A bullet, e.g. from a personal weapon, is stopped very rapidly in water. In the case of an illuminating shell, in practice always a fire hazard, the shell is in addition quenched immediately.

When a bullet penetrates into an element, a strong blast wave is produced and it is therefore particularly important that this too can be damped immediately without causing any damage and can be absorbed after a short time. Otherwise, the elements comprising the gel-like superabsorber would be torn to pieces by the blast wave.

The bullet penetrates to a greater or lesser degree into the element according to its speed, weight and calibre. As a rule, the depth of penetration is at most approximately 20 cm. For safety reasons, however, a bullet catcher must have a depth of at least 50 cm. This is particularly important when using round or rounded elements comprising intermediate chambers.

Therefore, elements comprising a bellows-shaped folded cover are advantageously used. Upon water-absorption, these elements swell into an essentially rectangular shape and offer little space for intermediate chambers.

In order to prevent premature swelling of elements, they are advantageously stored and transported individually or in groups in a tearable, water-impermeable protective film. In addition to the tear means, this protective film can also have one or more carrying handles. The cover of an element preferably consists of water-permeable non-woven fabric, woven fabric, knitted fabric or netting. Mineral, polypropylene, polyester and/or polyamide fibres which form a non-woven fabric, and are woven, knitted or bonded into a net, have an extremely good tear strength, even after water- absorption.

The dimensional stability of the cellulose pulp is advantageously increased by joining the cellulose fibres together at points by thermoforming with polyethylene fibrils, e.g. with the product PULPLUS by DuPont, although the extensibility of the cellulose pulp must not be affected, or at least not to a significant extent.

The additional extensibility of the cover of a cellulose pulp saturated with water is preferably at least 10 %. This extensibility serves, as mentioned, to catch and damp the blast wave produced upon the penetration of a bullet. The extensibility can be guaranteed, e.g. by means of a not completely extended bellows device, an extensible knitted fabric, or the formation of a relatively large bulge. However, the bullet catcher must be designed in such a way that in the event of temporary expansion in order to catch and damp the blast wave, no through passage is produced for any bullets appearing at the same time.

Furthermore, the bullet holes should not tear through the cover during expansion.

Dry elements are preferably connectably or releasably joined together. It is easier to stack connectable elements into a bullet catcher if the use of one individual element is not sufficient. Dry elements already joined together can be stacked particularly easily into a bullet catcher if they are joined together in a releasable manner. Therefore, the necessary elements can be taken from a folded stack or from a roller and then used. In this manner, instead of individual elements, the entire stack or the entire roller can be protected by a moisture-impermeable plastic cover.

The elements can be divided into several chambers by means of longitudinal and/or transverse walls, these walls being produced by sewing, gluing or welding.

According to a first variant, a bullet catcher produced by the process according to the invention is used as a military combat shelter, especially a temporary one.

The stacked or rolled dry elements can also be carried along by a small combat group formation, protected against moisture with a protective cover, as their weight is extremely low and they take up little space.

Only water absorbed in seconds with a corresponding expansion of volume is used for the production of the temporary combat shelter. Protection for up to the group formation can also be produced within a few minutes, even if the terrain is ill- suited to manual digging.

It is particularly advantageous to add, e.g. earth or sand to the combat shelter produced according to the invention. This not only means that gaps can be filled in an improved manner, but, in addition, increases the psychologically important feeling of safety of the soldiers. The temporary combat shelters are quite sufficient for short- time occupation. For longer occupation, conventional digging can be effected in order to safeguard and supplement the temporary combat shelters.

According to a second variant, a bullet catcher produced according to the invention can be used behind a target surface or a target of a shooting range, either indoors or outdoors. A bullet catcher according to this invention can be exchanged in a simple manner once the predetermined shot quota has been reached or in the event of damage. Therefore, a bullet catcher in a shooting range preferably consists of several elements having a final weight of approximately 20 to 30 kg, wherein the elements to be exchanged can be removed individually in a simple manner. The bullets penetrating therein can be recovered upon disposal.

A bullet catcher according to the invention has the advantage, both in military combat and in a shooting range, that no ricochet shots can be produced.

Several embodiments of the invention, also the subject of dependent claims, will now be described in more detail with reference to the accompanying drawings, in which:

Fig. 1 is a schematic view of a temporary military combat shelter for two infantrymen;

Fig. 2 is a schematic view of a covered, dry element comprising a superabsorber;

Fig. 3 is a diagrammatic transverse section along the line III-III of Fig . 2 ;

Fig. 4 is a schematic view of a bellows-shaped folded dry element;

Fig. 5 is a diagramatic section through an element according to Fig. 4 after water-absorption, and

Fig. 6 is a schematic view of elements joined together, after water-absorption.

The bullet catcher 2 illustrated in Fig. l serves as a temporary military combat shelter for two infantrymen 4, each armed, inter alia, with an automatic rifle 6.

The bullet catcher 2 consists of elements 14 arranged alongside and behind one another, the said elements containing a superabsorber swollen with water. In this case, the geometrical dimensions of the elements 14 are different. This has the advantage that no joints have to be arranged behind one another. On the other hand, the disadvantage has to be accepted that two different types of dry elements 14 must be carried along, if these are not to be joined to form a unit consisting of two rows.

According to a variant which is not shown, the elements 14 are of equal size, but are at least laterally displaced. The height is also preferably displaced, something being placed underneath one row, e.g. loose earth material 8.

The bullet catcher 2 can also be designed to be half this height, the infantrymen 4 then only being protected in the horizontal position.

Furthermore, earth material 8 or sand is preferably inserted into the joints and/or scattered over the bullet catcher 2. This not only increases safety and the feeling of safety of the infantrymen 4, but also camouflages the bullet catchers 2. In the case of combat shelters of a less temporary nature, the entire bullet catchers can be heaped or piled up with earth or sand.

A bullet 10 that has penetrated into an element 14 is shown on an extremely exaggerated scale, this bullet having been stopped after a depth of penetration of approximately 15 cm, and now sitting loosely in the swollen mass of the element 14.

Folds 12 are still visible in the elements 14 which are bellows-shaped in the dry state. These guarantee extensibility of approximately 15 % for damping and absorbing blast waves.

Figures 2 and 3 illustrate an element 14 comprising several sheets of non-woven fabric stacked on top of one another, superabsorbent material being applied thereto. In terms of its function, the non-woven fabric comprising a superabsorber corresponds to a cellulose pulp 16 with an interspersed superabsorbent material. Accordingly, the reference numeral 16 is used to designate both non-woven fabric comprising a superabsorber and a cellulose pulp comprising a superabsorber. The sheets of non-woven fabric stacked on top of one another are held together by a cover 18 of a water-permeable knitted fabric of tear-resistant synthetic fibres. The non-woven fabric comprising a superabsorber is dry and has therefore not yet absorbed any water. The two halves of the cover 18 form a circular border 20, formed of two outer faces of the cover stuck together in a watertight manner.

The upper border 20 is broader and a handle 22 can be cut out, indicated by a dotted line. Of course several handles 22, eyelets, tabs and the like are also possible.

Overall, the element 14 is of a flat design and can be stacked and transported in a manner requiring little space. After water-absorption the cover 18 bulges to such an extent that the element 14 is almost round. Several round elements arranged behind one another in a dense spherical pack produce an excellent bullet catcher.

Figures 4 and 5 show an element 14 provided with a cover 18, and filled with cellulose pulp 16 which contains a superabsorber, before and after the absorption of water. The element 14 lying on the ground has a bellows-shaped folded side wall 26, which is almost extended upon water-absorption. Therefore, the cover retains a residual extensibility of approximately 12 %, which serves to take up and absorb blast waves produced upon the penetration of a bullet.

Another, e.g. two to six carrying tabs (not shown) can be secured in the region of the upper part of the cover 18.

The design of a bullet catcher 2 according to Fig. 1 is based on elements 14 according to Figures 4 and 5.

The device according to Fig. 6 consisting of several elements 14, formed of a cellulose pulp 16 and a cover 18, is set out on the ground 28. The borders 20 of the covers 18 stuck together have eyelets and can be connected by appropriate means. A hook 32 can already be inserted into one of the two adjacent eyelets 30.

Sheets of elements 14 according to Fig. 6 can be arranged in layers behind and on top of one another, the borders 20 of two sheets not lying behind one another and the region thereof preferably being filled with a filling material, such as earth or sand.

Before use, the elements 14 joined together can be rolled up or folded, this saving space, allowing for simple transportation and being suitable for rapid unfolding.

Claims

-II-C AIMS

1. Process for the production of a bullet catcher (2) for stopping bullets (10), characterised in that at least one element (14) comprising an all-round water-permeable tear- resistant cover (18), which accommodates a cellulose pulp (16) comprising a superabsorber in an expanding closed inner chamber, is arranged at the place where the bullet catcher (2) is to be produced and water is supplied to the swelling elements (14) until saturation thereof, thereby forming a gel, the extensibility of the cover (18) being retained even when the pulp (16) is completely saturated with water.

2. Process according to claim 1, characterised in that the elements (14) are arranged in such a way that a bullet catcher in general at least 50 cm deeper is formed in the direction of shooting.

3. Process according to claim 1 or claim 2, characterised in that elements (14) with a bellows-shaped folded cover (18) is used.

4. Process according to one of claims 1 to 3, characterised in that elements (14) with a cover (18) of a non-woven fabric, woven fabric, knitted fabric or netting are used, preferably of mineral, polypropylene, polyester and/or polyamide fibres.

5. Process according to one of claims 1 to 4, characterised in that elements (14) comprising a pulp (16) which has cellulose fibres joined together at points with polyolefin fibrils is used.

6. Process according to one of claims 1 to 5, characterised in that elements (14) with a cover (18), the extensibility of which after saturation of the cellulose pulp (16) with water is still at least 10 %, are used.

7. Process according to one of claims 1 to 6, characterised in that elements (14) which are connectable, can be joined together and/or can be divided into chamber by intermediate walls are used.

8. Use of a bullet catcher (2) produced by the process according to one of claims 1 to 7 as a military combat shelter.

9. Use of the bullet catcher (2) according to claim 8 with additional, especially gap-filling, earth material (8) or sand.

10. Use of a bullet catcher (2) produced by the process according to one of claims 1 to 7 behind a target surface or a target of a shooting range.