EP0142717B1 - Blasting device for precision blasting - Google Patents

Description

The invention relates to an explosive tool for single use for precision blasting, to which an explosive can be attached. This is assumed to be known.

From US-A-232640 it is known for blasting rocks to contain the explosive charge instead of sand or earth by means of a sack filled with water. However, such a sack is difficult to handle and, due to the lack of a precise geometric assignment of the explosive charge to the water sack, it is not possible to carry out precision explosions.

The problem of targeted explosions while protecting the environment has been tried several times in the past. For example, an explosive device is known from US-A-2 797 892, which has a stable, bell-shaped protective housing, which is filled with a shock-absorbing material in the form of hard foam rubber, foam glass or similar material and which has a downwardly opening recess in which the explosive is inserted in the form of a cutting charge. The task of the shock-absorbing filling is to reduce the pressure surge on the side facing away from the direction of action of the cutting charge by absorbing “deformation work” in order to protect the immediate surroundings. In this known blasting device, the housing serves exclusively as a protective housing and must be made very thick-walled in order to achieve the desired protective effect here at all. This means that practically only handling with hoists is possible and the size of the explosive charge that can be used is very limited. Handling as an explosive device for police use or for rescuing spilled people in the event of a disaster is therefore excluded. A targeted blasting to create an opening in the form of a "manhole" in a building wall with small amounts of explosives, that is, without endangering the building itself, is also not possible with the known device.

From GB-A-655 921 it is also known to apply a detonating cord prepared as a cutting charge to a flexible carrier surface, for example in the form of a rectangle, to detonate openings in an aircraft fuselage, to place this over a holder on the aircraft fuselage and then to carry out the detonation . Since the detonating cord is designed as a cutting charge and the surrounding air must act as a damper, the flexible carrier is not suitable for this because of its low mass, only thin-walled materials such as the wall of an aircraft fuselage can be blown through. The blasting of building walls, especially inside walls in buildings, is not possible at all because of the insulation by the ambient air and the considerably higher amount of explosives required with larger wall thicknesses, since the detonation damages the building, if not causes it to collapse. The desired precision blasting on building walls in disaster relief cannot be carried out with this previously known cutting charge.

From US-A-4301707 an arrangement is known for blasting off an aircraft cockpit or for blasting out an emergency exit in an aircraft fuselage, in which an explosive cord is embedded in the wall to be blasted or is placed in an outer holding strip with a metallic shield. It is therefore an integrated system that cannot be used for any application and that is only suitable for small amounts of explosives in view of the low level of insulation caused by part of the wall to be blasted and therefore only for blasting very thin walls.

The invention is based on the object of creating an explosive tool which can be used to meet the requirements of special applications, for example in disaster relief or in police use. Here there is a need to carry out explosions in rooms and in the immediate vicinity of people, for example creating a passage through a building wall. It is important to measure the explosive charge in such a way that the material is loosened or penetrated to the desired extent, but that neither by damaging the explosive charge nor by the parts detached from the material to be loosened or penetrated from the explosive charge, For example, people in the room to be opened by the blasting are injured. The decisive factor here is the dimensioning of the amount of explosives in relation to the material to be loosened or penetrated, and the dimensioning of the dam in relation to the selected amount of explosives. In the event of a disaster, it is often necessary to carry out an explosion in the shortest possible time, which was not possible with the methods known hitherto.

This object is achieved in that the explosive tool consists of a hollow body which is closed on all sides and which is provided for receiving a non-combustible liquid as a insulating material, that the hollow body is provided with a contact surface which serves to attach the explosive tool to a surface of the object to be detonated the hollow body partially encloses the explosive on the outside, for this purpose at least one recess, which is allocated within the extension of the contact surface and is partially delimited by it, is provided in the hollow body wall for receiving the explosive, and the hollow body is so thin-walled but at the same time dimensionally stable that there is a defined assignment of the explosive to the explosive tool and to the object to be detonated.

Such an explosive tool makes it possible to combine the explosive and the dam in one element, so that not only is the handling considerably simplified, but the explosive tool can also be attached regardless of the position of the surface to be penetrated. There is a wide variation possibility for the manufacture and use of such blasting tools, in such a way that different contours of the opening to be achieved are available for a given liquid insulation material, in particular in the case of strip-like insulation bodies. Another advantage is that the manufacturing process and warehousing are simplified and inexpensive materials can be used. Extrusion processes or the like can preferably be used for the production of the hollow body, so that soft and / or hard plastics, rubber-like materials or even metals can be used as materials for the hollow body. Plastics, for example PVC, offer the advantage that when the detonation is detonated, the wall of the hollow body is broken down into such small pieces that there is no risk of injury to people who have to be in the immediate vicinity of the charge when detonating. The wall thickness need only be dimensioned so that for handling, i.e. Storage, transport and attachment the wall of the hollow body can not be pierced or burst under bending stress. The material and the thickness of the walls of the hollow body must be dimensioned such that the hollow body filled with the insulating liquid can be handled in a dimensionally stable manner.

A non-flammable liquid is used as the insulation material. Water is particularly suitable for this because it has significant advantages both in terms of its density and its chemical safety. If, for example, water is enclosed as a insulation material in a hollow PVC body, the amount of water enclosed by the hollow body is atomized during the explosion, in which the hollow body is broken down into fine particles. Health damage to people who are at the blasting site cannot occur, so that the blasting tool can also be used in closed rooms. Instead of water, other non-flammable, also highly viscous liquids, but also liquid mixtures can be used. In a preferred embodiment, in order to increase the availability of the blasting tool according to the invention, it is provided that the liquid has a solidification point below the freezing point. When using water as a insulation material, this can be done, for example, by adding appropriate antifreeze.

If, according to an embodiment of the invention, fastening means are arranged in the area of the contact surfaces, it is possible to attach such an explosive tool not only to inclined or vertical surfaces, but also overhead and to carry out corresponding explosions in such constrained positions. The particular advantage of such an explosive tool is furthermore that prefabricated hollow bodies of different sizes can be kept on standby in order to be able to cover different explosive quantity ranges in the manner of a “map”, so that in each case an easily manageable dam for the explosive quantity specified by the explosive task To have available. The explosives can either be introduced into the depression on site or can already be connected to the hollow body at the factory. If several recesses are provided, it is also possible to provide the hollow body with a basic charge in the factory, which can be reinforced according to the requirements on site by the subsequent introduction of further amounts of explosives into a still open recess.

Explosives which are easily separable and easily portionable, such as plastic explosives or detonating cords, are preferably used. The contact surface, in particular a contact surface provided with an adhesive layer, brings about a good “coupling” of the tool to the surface to be blasted.

In a preferred embodiment, the hollow body is designed as an elongated strip and the depression as a continuous groove. This makes it possible to manufacture blasting tools of different lengths, and here too there is the possibility of providing a certain “division grid” so that certain contours, for example openings in walls of any desired size, can be blasted by assembling several hollow bodies. The strip-shaped hollow body can be straight or curved. Furthermore, it is possible to provide contours that are already predetermined for standard cases, for example by a frame-shaped design of the explosive tool. This not only leads to a simplification in the manufacture of the hollow body, since this can then be produced as a strand, but also allows variation options in the selection of the explosive to be used, since the continuous groove in each case offers the possibility of using detonating cords, but at the same time other explosives, for example plastic explosives, can be introduced in a simple manner, it not being necessary to fill the groove in full length with explosives for a given hollow body. This increases the availability of the blasting tool according to the invention.

The arranged in the area of the contact surfaces In a preferred embodiment, the fastening means are formed by an adhesive layer applied to the contact surface. Silicon-based adhesives are preferably used here, which have the advantage of also adhering to rough walls, so that it is possible to attach the blasting tool to an inclined or vertical building wall or else overhead to a part of the building. The high adhesiveness of such silicone adhesives also allows the explosive tool to be attached to the surface in question with little effort. The adhesive layer does not need to be applied continuously over the contact surface, but can also be applied in zones or at points on the contact surfaces on both sides of the depression.

In the case of explosive tools which have already been provided with explosives in the factory, this is fastened in the depression by means of adhesive or the like. In a preferred embodiment, however, it is provided that the depression is provided with holding means for the explosive. This makes it possible to fix the explosive in the recess, the holding means being able to be adapted to the packaging of the explosive used in each case. These holding means ensure that the complete blasting tool, i.e. the hollow body with the inserted explosives can be safely brought to the place of use even in difficult situations and can be attached to the explosive site without the risk of the explosive detaching from the hollow body. Depending on the packaging of the explosives used, various holding devices can be considered. For example, it is possible to fix an explosive cord in the recess using adhesive, for example silicone adhesive. This can be done both when the complete blasting tool is completed in the factory and when the blasting cord is inserted on site.

In a preferred embodiment of the invention it is provided that the holding means are formed by fastening claws which protrude into the depression. Such preferably resilient fastening claws simplify the handling of the explosive tool in such a way that the connection between the dam and explosive, in particular explosive in the form of a detonating cord, can be made very quickly on site without additional aids, since the detonating cord can only be pressed into the recess needs and is then held in position by the fastening claws. Even when plastic explosives are pressed into the recess, fastening claws of this type ensure that the explosive is securely fastened in the recess.

For so-called single loads, in which the hollow body is approximately pot-shaped, it is provided in an embodiment of the invention that the recess has a cross section that widens into the hollow body. This makes it possible to use the blasting tool in the manner of a so-called cutting charge, wherein the use of the erfi _h to the invention the hollow body, in conjunction with the conically towards the mouth of the recess narrowing forming a concentration of the explosive effect on the breakdown location. Compared to conventional loads, there is the option of using a smaller amount of explosives, depending on the application, highly explosive explosives can also be used instead of commercial explosives. With a blasting tool of this type, it is possible, for example, to blast openings in the case of catastrophe operations in reinforced concrete ceilings, which then make it possible to make contact with spilled people and, if necessary, to introduce supply lines into the cavity.

Another embodiment of the invention provides for the explosive tool to be used as a cutting charge in the true sense. Here, according to the invention, the depression is conical, the cone tip pointing into the hollow body, and that the explosive consists, in a manner known per se, of a shaped body which is designed as a hollow cone. This results in the possibility of carrying out explosions with such cutting charges with much smaller amounts of highly explosive explosive, since instead of the insulation by the ambient air, the insulation is now carried out by the liquid-filled hollow body. The load on the environment from the detonation shock is considerably reduced, so that such a cutting charge, which could previously only be used in the military, can now also be used in the civilian sector, for example in the event of a disaster.

In an embodiment of the blasting tool for separating rod-shaped objects, in particular steel cables using blasting technology, it is provided according to the invention that the contact surfaces are formed by a slot-like recess, that the recess containing the explosives in the bottom region of the slot opens into the latter and that the recess extends from one side the mouth enclosed by the hollow body extends into the hollow body. Such an explosive device represents a single charge, which can be placed like a rider on the rod-shaped object to be separated, in particular a steel cable, which is then almost punctured after the explosive is detonated. For such applications, a highly explosive explosive is expediently used with a transfer speed of over 7000 m / s, so that the rope to be separated is already destroyed by the detonation impact.

In an expedient embodiment of the invention, for blasting tools designed as a single charge, the hollow body is provided with one leading outward from the depression Ignition channel is provided. This means that the hollow body lies tightly on the counter surface at the explosive site and the energy of the explosive is almost fully available at the penetration site. It is also advantageous here if the ignition channel opens into the depression in the region of the mouth. This has the advantage that the ignition first takes place in the muzzle area, i.e. in the immediate vicinity of the penetration point, and so the amount of explosives is ignited from the muzzle into the depression, so that the explosive energy is always present in the muzzle area, which, even with highly explosive explosives, leads to one Leads to an increase in the penetration rate.

One embodiment is based on the task of designing an explosive tool of the type described at the outset in such a way that factory production based on simple series parts is possible as far as possible, so that the hollow body can be stored as an empty pre-fabricated stock and in use only with explosives, detonators and Insulation material is to be provided.

This object is achieved according to the invention in that a closure piece is arranged on at least one end of the hollow body, which is provided with at least one closable filling opening for the insulation material and which is connected to the groove-like recess and is closed off from the interior of the hollow body, preferably transversely to the body axis extending bore. A closure piece designed in this way allows the hollow body to be produced, for example, from an extruded hollow plastic profile in such a way that sections cut to length from a profile strand, for example in accordance with a predetermined grid dimension, are used, the free ends of which are closed with closure pieces of the aforementioned type, for example by gluing, welding or the like. Liquid-tight connection. The filling opening can be closed by a simple, preferably elastic stopper. The bore running transversely to the axis of the hollow body and reaching into the groove-like depression allows either an explosive cord guided in the groove-like depression of the hollow body to be led out, which can then be connected to an ignition means, or through this hole the ignition agent into the Introduce the area of the groove-like depression filled with explosives, both in the form of a simple detonating cord and in the form of a detonator, which is inserted into the bore and acts on the explosive when detonated.

In a preferred embodiment of the invention it is further provided that the closure piece has in its edge region a recess aligned with the groove-like recess of the hollow body. This configuration has the advantage that when used as an extension or corner connector, the explosive, for example an explosive cord, can be passed through the recess of the explosive tool without interruption through this recess. If such a closure piece is used as an end piece, it is possible either to lead the explosive axially out of the hollow body or to introduce the ignition means, for example an ignition cord or a detonator capsule, into the groove-like depression in the axial direction.

In a preferred embodiment of the invention it is provided that an axially removable, hollow extension is arranged on the closure piece of one end of the hollow body, which is provided with a detachable ignition wire coil, which is connected at one end to an explosive device fastened in the groove-like recess of the closure piece and that an ignition switch and a usable ignition battery are arranged inside the extension. This configuration is preferably provided for police applications in which the attachment of the blasting tool and the ignition must follow one another within a very short time. As a rule, there is no time here to arm the explosive-filled and explosive-equipped explosive tool by inserting the ignition means and connecting it to the ignition device. Due to the special shape of the closure piece, it is possible to prepare such an explosive tool complete with a filler, explosive and detonator, the detonator, here the detonator, is already connected to an ignition switch via the ignition wire. The explosive tool is armed in the present case by inserting the ignition battery. The blasting tool, which is provided on its contact surface with an adhesive, for example a self-adhesive layer, can now be attached to the blasting site after the extension has been removed. If the operator now holds the extension in his hand and goes to safety, the ignition wire is removed from the winding and the detonation can be triggered by actuating the ignition switch as soon as the operator has reached an appropriate safety distance.

In an expedient embodiment of the invention, the ignition switch is arranged in the interior of the extension in such a way that it is only accessible through an opening that becomes free after the extension has been removed. This ensures that even after the blasting tool has been armed by inserting the ignition battery, the blasting tool cannot be inadvertently triggered, which is of particular importance in police use.

In an embodiment of the invention, the ignition wire winding is arranged on part of the outer surface of the extension. This also allows a check to be carried out immediately before use of the ignition wire winding, so that proper removal is ensured after attaching the blasting tool.

In another embodiment of the invention it is provided that the ignition wire winding is held on a preferably conical winding mandrel which is arranged in the interior in the pulling-off direction of the extension. Here, only a slight taper of the winding mandrel is required, which ensures that the ignition wire is pulled off the winding properly. The arrangement of the ignition wire winding in the interior of the extension has the advantage that any damage to the ignition wire due to transport and / or storage is excluded. It is expedient if, in a further embodiment of the invention, a releasable separating agent, for example a paper sleeve or the like, is arranged between the ignition wire winding and the outer surface of the winding support.

• Fig. 1 perspektivisch ein leistenförmiges Sprengwerkzeug;
• Fig. 2 einen Querschnitt durch ein als Einzelladung ausgebildetes Sprengwerkzeug;
• Fig. 3 einen Querschnitt durch ein als Schneidladung ausgebildetes Sprengwerkzeug;
• Fig. 4 einen Querschnitt und
• Fig. einen Längsschnitt durch ein Sprengwerkzeug zum Durchschlagen stabförmiger Gegenstände;
• Fig. 6 eine Aufsicht auf ein in das leistenförmige Sprengwerkzeug einschiebbares Verschlussstück;
• Fig. 7 einen Querschnitt durch das Verschlussstück entsprechend der Linie 111-111 in Fig. 2;
• Fig.8 einen Längsschnitt gemäss der Linie IV-IV in Fig. 2;
• Fig. 9 einen Längsschnitt gemäss der Linie V-V in Fig. 2;
• Fig. 10 ein Hohlprofil im Schnitt mit Befestigungsmitteln für eine Sprengstoffschnur;
• Fig. 11 ein Sprengwerkzeug mit Verschlussstück und Verlängerung mit Zündeinrichtung in abgezogenem Zustand.

The invention is explained in more detail with reference to schematic drawings of exemplary embodiments:

• 1 shows a strip-shaped blasting tool in perspective;
• 2 shows a cross section through an explosive tool designed as a single charge;
• 3 shows a cross section through an explosive tool designed as a cutting charge;
• Fig. 4 shows a cross section and
• A longitudinal section through an explosive tool for penetrating rod-shaped objects;
• 6 shows a plan view of a closure piece which can be inserted into the strip-shaped explosive tool;
• 7 shows a cross section through the closure piece along the line 111-111 in Fig. 2.
• 8 shows a longitudinal section along the line IV-IV in Fig. 2;
• 9 shows a longitudinal section along the line VV in FIG. 2;
• 10 shows a hollow profile in section with fastening means for an explosive cord;
• Fig. 11 shows an explosive tool with a closure piece and extension with ignition device in the removed state.

The embodiment shown in Fig. Of a strip-shaped explosive tool consists of a thin-walled hollow body 1, the cavity on all sides, i.e. is also closed on the end faces and filled with a insulation material 2. The hollow body is made for example from a plastic such as PVC or the like.

As can be seen from the end face shown as a section, the explosive tool defined by the hollow body 1 in its shape has a preferably flat contact surface 3 which delimits an open recess 4 formed as a groove on both sides. An explosive 5, for example an explosive cord, is introduced into this groove 4, which is formed by holding means 6 in the form of adhesive dots, clips or, as shown here, projecting fastening claws. In the end region of the recess 4, the detonating cord 5 is provided with a conventional connection means (not shown here) for connection to the ignition means.

A blasting tool designed in this way can be brought ready for use to the place of use, connected there with the ignition means and ignited, the blasting tool being placed with the open side of the groove-shaped recess 4 on the medium to be penetrated. In the case of horizontal or only slightly inclined surfaces, it is sufficient to place the explosive tool on the surface. In the case of strongly inclined or vertical surfaces or when installing overhead, for example under a building ceiling, it is necessary to provide the explosive tool with the appropriate fastening means. In its simplest form, this is possible in such a way that an adhesive, preferably a silicone-based adhesive, is applied to the contact surface 3 in zones or in a continuous layer 7, which also holds the explosive tool in the predetermined position on vertical surfaces after pressing . The use of silicone-based adhesives with the appropriate layer thickness makes it possible to achieve sufficient adhesion even on flat or dusty surfaces. Like the explosives, the adhesive layer can only be connected to the liquid-filled hollow body at the place of use.

Instead of the arcuate cross-sectional shape shown, a rectangular or trapezoidal cross-sectional shape can also be specified for the hollow body. Furthermore, it is possible to arrange two or more depressions next to one another instead of just a groove-shaped depression in order to be able to use an explosive tool for different charge strengths by filling one or more depressions with explosive according to the desired charge strength.

As stated at the beginning, several strip-like explosive tools, as shown in the figure, can be combined with one another for use, for example four such explosive tools in the form of a frame being attached to the wall in order to create an opening in a building wall. If certain shapes have to be used repeatedly, it is also possible to prefabricate complete frames on the basis of such strip-shaped blasting tools, which only have to have an interruption for the supply of the ignition means at at least one point.

The explosive tool for a single charge shown in cross section in FIG. 2 consists of a cup-shaped, thin-walled hollow hollow body 8, for example made of a plastic with a circular or a square outline. The hollow body 8 is in turn like a non-flammable liquid Water or the like filled as a dam. The hollow body 8 has a preferably flat contact surface 10 which surrounds an opening 11 of the recess 4 on all sides for receiving the explosive. In the exemplary embodiment, the depression is designed in such a way that it has a cross section that widens into the hollow body 8 starting from the mouth, so that the blasting energy is concentrated on the penetration point. The hollow body 8 is provided with a laterally outwardly directed ignition channel 12 which is sealed off from the cavity and through which the ignition means, for example an explosive capsule which can be ignited electrically or by means of a detonating cord, can be introduced into the recess 4 and brought into connection with the explosive. The ignition channel 12 expediently opens out in the vicinity of the mouth 11 of the depression 4, so that the explosive is detonated in the immediate vicinity of the penetration point specified by the mouth 11. If such an individual charge is placed, for example, on a reinforced reinforced concrete ceiling 13, it is possible to blow up an opening 14 which widens accordingly in a funnel shape.

Fig. 3 shows another embodiment of the explosive tool for a so-called cutting charge. The hollow body 8 is here again thin-walled and filled with a liquid, for example water as a insulating material. The recess 4 _' is again approximately conical, but in contrast to the embodiment according to FIG. 2 such that the conical tip 15 of the recess 4' points into the hollow body. The explosive is formed by a shaped body 16 which forms a hollow cone in a manner known per se. Compared to the previously known cutting loads, this system offers the same effect with less use of explosives because of the more effective insulation.

4 and 5, an explosive tool is shown, as it is used in particular for the detonation of rod-shaped objects, for example steel cables. Here too, a hollow body 8 is again provided, which is thin-walled and filled with a liquid, for example water, as a insulating material. As can be seen from the two cuts at 90 ° to each other according to FIGS. 4 and 5, here too the recess 4 is conical in shape against the mouth 11 and is filled with explosives, preferably highly explosive explosives. In contrast to the other embodiments, the contact surface 3 _{'is formed} by a slot-like recess in the hollow body, the mouth 11 of the recess 4 being in the bottom region of this slot. The hollow body also has an ignition channel 12 which is guided laterally from the outside into the recess 4 and through which the ignition means, for example an ignition capsule 17, can be connected to the explosive.

When in use, the blasting tool is placed like a rider on a steel cable 18 to be penetrated, as can be seen from the two sectional views.

1 shows a top view of a closure piece with which the free ends of the hollow body 1 shown in FIG. 1 can be closed. The exemplary embodiment shown shows a closure piece which, at the same time, as an extension piece, permits the connection of several individual hollow body pieces. The closure piece 20 here essentially consists of a thin-walled plate 21, on the plate level of which a circumferential web 22 is arranged on both sides, the outer contour 23 (FIG. 7) of which corresponds to the inner contour of the cross section of the hollow body 1, so that the closure piece in the Hollow body can be inserted and glued to it. On the inside of the web 22, two filler channels 24 are arranged which penetrate the thin-walled plate 21. When used as a closure piece, these filling channels also form the filling openings, which can then be closed by a sealing plug, not shown, preferably made of an elastic material, after filling with the insulating material.

In the area of the thin-walled plate 21 there is a bore 25 which runs transversely to the longitudinal extent of the closure piece and opens into the groove-like recess 4, which is also present on the closure piece in accordance with the cross section of the hollow body. This bore 25 has no connection with the interior of the hollow body.

As can be seen from the top view according to FIG. 6, circumferential projections 26 can be arranged at a distance from the plate 21 on the outer surface 23 of the webs on both sides of the bore 25, which serve as stops when inserted into the hollow body 1.

9 and 10 show the longitudinal sections indicated in FIG. 6, which illustrate the arrangement of the plate 21 on the one hand and the bore 25 on the other. In the longitudinal section according to FIG. 8, the closure piece is also shown pushed into a hollow body 1, the one visible filler channel being closed with a closure plug 27. As can be deduced from the longitudinal section according to FIG. 8, a detonator inserted into the bore 25 from above protrudes with its tip into the groove filled with explosive 4 (in use), so that when the detonator is detonated, it detonates directly onto the detonator Explosives. In the illustrated embodiment of a closure piece, which can also serve as an extension piece, a detonator capsule can be inserted not only in the end region of the blasting tool, but also at any desired joint of a strip-shaped blasting tool composed of several parts.

In Fig. 1 is a hollow body of the explosive device ges shown, the groove 4 is provided with bracket-shaped fasteners. In Fig. 10, an embodiment is shown in a cross section, which according to the embodiment. Fig. 1 has manufacturing advantages. In this embodiment, an extruded hollow plastic profile is again used, the groove-shaped recess 4 of which is dimensioned such that the largest detonating cord for the given profile can be inserted. The simplification of the construction is that there is no need for additional fastening claws or gluing the detonating cord 5 into the groove 4. The attachment of the detonating cord, which can also have a smaller diameter than the maximum permissible cord thickness, is held in the groove 4 in the exemplary embodiment shown in FIG. 10 in that a self-adhesive adhesive tape 28 is applied to the contact surface 3 on both sides of the groove 4 is provided on its outer surface with a removable protective cover 29 made of paper or the like. The adhesive strips applied to both sides of the groove 4 are now dimensioned in such a width that they cover the groove 4 from both sides and only leave a narrow slot above the groove 4. The slot allows a thin detonating cord to be inserted into the groove 4, which is then held in the groove by the edges of the adhesive strip 28 covering the groove 4. Correspondingly thicker detonating cords can, as in the embodiment according to. Fig. 9 are pressed into the groove 4 so that they are held there with a positive fit.

FIG. 11 shows an embodiment in which a closure piece 20 corresponding to the design shown in FIG. 6 is firmly connected to a hollow body 1 by gluing or welding. The hollow body 1 is tightly closed at its other end, for example by a corresponding closure piece and filled with an insulating material, for example water. Explosives, for example an explosive cord 5, the free end 30 of which is fixed in the bore 25, are introduced into the groove-like depression.

On the side of the closure piece 20 facing away from the hollow body 1, a detonator capsule 31, the ignition wire ends 32 of which are fastened to the inside of the web 22, is arranged in the corresponding groove-like depression in the web. On the inside of the web 22, the free end 33 of an ignition wire coil 34 is also fastened and connected to the ignition wire ends 32 of the detonator capsule 31.

In the example shown here, the ignition wire winding 34 is fastened on a winding mandrel 35 inside an extension 36, which has a cross-sectional profile corresponding to the web 22 and can be pushed onto this. The ignition wire coil 34 is wound here in such a way that the ignition wire 33 can be pulled off the explosive tool in the direction of arrow 37 when the extension 36 is pulled off, so that the operator can remove himself from the explosive site after the explosive tool has been attached. Instead of an internal winding mandrel, the ignition wire winding 34 can also be applied to the outside of the extension 36, preferably at the end facing the closure piece 20. The other end of the extension 36 is expediently provided with a handle or finger grip or a grip loop (not shown here).

An ignition switch 38 is also fastened in the interior of the extension 36, the switch handle 39 of which can be actuated by a finger through a recess 40 in the wall of the extension 36. The assignment of the switch handle 39 to the recess 40 is provided in such a way that when the plug is in the switch handle 39 is covered by the corresponding part of the web 22, so that the switch handle 39 is only released when the extension 36 is removed from the explosive tool. The ignition wire coil 34, which is formed either from a two-wire wire or from two parallel wires, is connected with its end located in the extension 36 to the ignition switch 38, the ignition switch 38 is also provided with two external contacts 41 for an ignition battery 42. For the ignition battery 42, a holder, not shown here, is expediently provided in the interior of the extension 36, which allows the ignition battery to arm the explosive tool only when it is in use through an opening 43 in the rear wall 44 of the extension 36. Resilient catches or the like, which can also be molded into the holder from plastic, ensure in the usual way that the ignition battery 42 is pressed in a contact-safe manner against the connection contacts 41 of the ignition switch 38.

To blow up a wall breakthrough, especially in emergencies, in which it is rarely possible to determine the thickness of the wall to be blown with sufficient certainty, it is particularly expedient if the strip-shaped insulation bodies are assembled in an X-shape. This has the advantage over a blasting tool assembled in the form of a frame that, in the area of the crossing point, the damper body has a greater amount of explosive available relative to the area covered by the blasting tool. When firing, the main effect that opens the masonry therefore occurs in the intersection area, while the amounts of explosives towards the end area of the hollow body have a supportive effect that enlarges the opening.

The strip-shaped hollow bodies can be attached to the wall from individual pieces in X or cross shape. However, it is particularly expedient if an X-shaped connecting piece is provided, on the free ends of which the strip-shaped hollow bodies are fastened. Here This results in a much easier handling, in particular for emergencies, with the X-shaped arrangement also having the advantage that the explosive tool can be held at the intersection point with one hand and attached to the detonation point while, for example, the explosive wire is pulled with the other hand or the ignitor can be kept on standby. It is particularly expedient here if the respective transition area between the free ends of the X-shaped connecting piece and the hollow bodies connected to it is designed to be slightly flexible in the plane of the contact surface of the explosive tool, so that when the explosive tool is attached, unevenness in the masonry is easily compensated and thus one perfect adhesion between masonry and the pressure sensitive adhesive arranged on the contact surface is guaranteed. As a result, not only is the explosive tool securely attached to the wall, but also reliable insulation of the explosive located in the groove-like depression is provided. The X-shaped connecting piece can be designed approximately in the shape of the closure piece according to FIG. In this case, however, the through-channels for the liquid damper can be dispensed with, which is particularly advantageous when the individual arms of the blasting tool have to be connected to the connecting piece in a manner which is perpendicular to the plane of the contact surface. It is also expedient here if the connecting piece has a central bore for receiving an igniter and has a recess on the side of the contact surface which opens into the groove-like depression of the connected hollow bodies and which is connected to the central bore. When using detonating cords, this makes it possible to insert the detonating cords into the detonating tool in the form of an arc in two pieces, the two pieces of cord touching in the region of the mouth of the bore for the detonator.

Claims (24)

1. Blasting device for non-recurrent use for precision blasting, on which an explosive (5) is able to be applied, characterized in that the blasting device consists of a hollow body (1; 8) which is closed on all sides, and which is provided to receive a non-combustible fluid as tamping substance (2), that the hollow body (1) is provided with a contact surface (3) serving for the application of the blasting device on a surface of the object which is to be blasted, that the hollow body (1) partially surrounds the explosive (5) externally, whereby for this within the extent of the contact surface (3; 10) and partially delimited thereby at least one associated depression (4,4') which is open toward the exterior is provided in the wall of the hollow body to receive the explosive (5), and that the hollow body (1) is thin-walled but at the same time inherently stable such that there is a defined association of the explosive (5) to the blasting device and to the object which is to be blasted.

2. Blasting device according to Claim 1, characterized in that the tamping body (1) is constructed as an elongated strip and the depression (4) is constructed as a groove.

3. Blasting device according to Claim 1 or 2, characterized in that in the region of the contact surfaces (3) attachment means are arranged.

4. Blasting device according to Claim 3, characterized in that the attachment means is formed by an adhesive layer (7) applied to the contact surface (3).

5. Blasting device according to Claim 4, characterized in that an adhesive of silicone base is used.

6. Blasting device according to one of Claims 1 to 5, characterized in that the depression (4) is provided with holding means (6) for the explosive (5).

7. Blasting device according to Claim 6, characterized in that the holding means (6) are formed by attachment claws, which project into the depression (4).

8. Blasting device according to Claim 6, characterized in that the holding means (6) is formed by an adhesive layer, which is arranged at least in zones in the depression (4).

9. Blasting device according to one of Claims 1 to 8, characterized in that the fluid used as tamping substance (2) has a solidification point which lies below the freezing point.

10. Blasting device according to one of Claims 1 to 9, characterized in that the depression (4) has a cross-section which widens into the tamping body (8).

11. Blasting device according to one of Claims 1 to 9, characterized in that the depression (4') is constructed in a conical shape, whereby the apex (15) of the cone points into the tamping body and that the explosive in a manner known per se consists of a shaped body (16), which is constructed as a hollow cone.

12. Blasting device for the blasting of rod- shaped objects in particular steel cables according to Claims 1 to 10, characterized in that the contact surfaces (3') are formed by a slit-like recess, that the depression (4) containing the explosive opens out into the slit in the base region thereof and that the depression (4) widens from an orifice (11), surrounded on all sides by the tamping body, into the tamping body.

13. Blasting device according to one of Claims 1 to 12, characterized in that the tamping body is provided with an ignition channel (12) leading outwards from the depression (4).

14. Blasting device according to Claim 13, characterized in that the ignition channel (12) opens out into the depression in the region of the orifice (11).

15. Blasting device according to Claims 1 to 14, characterized in that at at least one end of the tamping body (1) a closure piece (20) is arranged, which is provided with at least one closable filling opening (24) for the tamping substance and which has a bore (25) which communicates with the groove-like depression (4), is closed with respect to the interior of the tamping body (1), and preferably runs transversely to the axis of the body.

16. Blasting device according to Claim 15, characterized in that the closure piece (20) has in its marginal region a recess which is in alignment with the groove-like depression (4) of the tamping body (1).

17. Blasting device according to one of Claims 15 to 16, characterized in that on the closure piece (20) of one end of the tamping body an axially removable extension (36) is arranged, which is hollow in construction and which is provided with a removable ignition wire strand (34), which is connected by one end into a blasting cap (31), which is attached in the groove-like depression (4) of the closure piece (20), and that in the interior of the extension (36) an ignition switch (38) and an insertable ignition battery (42) are arranged.

18. Blasting device according to Claim 17, characterized in that the ignition switch (38) is arranged in the interior of the extension (36) such that it is only accesible through an opening (40) which becomes free after the extension (36) is removed.

19. Blasting device according to Claim 17 or 18, characterized in that the ignition wire strand (34) is arranged on a part of the outer surface of the extension (36).

20. Blasting device according to one of Claims 17 or 18, characterized in that the ignition wire strand (34) is held on a preferably conical winding mandrel (35) which is arranged in the direction of removal of the extension in the interior.

21. Blasting device according to one of Claims 17 to 20, characterized in that between the ignition wire strand (34) and the outer surface of the winding carrier (outer surface of the extension or outer surface of the winding mandrel) a detachable separating means is arranged.

22. Blasting device according to Claims 1 to 21, characterized in that the strip-shaped tamping body is composed in an X-shape.

23. Blasting device according to Claim 22, characterized by an X-shaped connecting piece, on the free ends of which strip-shaped tamping bodies are attached.

24. Blasting device according to Claim 23, characterized in that the connecting piece has a central bore to receive an igniter, and on the side of the contact surface has a recess, which opens out into the groove-like depression of the connected tamping body and which communicates with the central bore.

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