Method for producing a cartridge case, and cartridge case

Abstract

The invention relates to a method for producing a cartridge case (1), in which method varying hardnesses (H) of the cartridge case (1) are produced in the axial direction (A) of the cartridge case (1). The invention also relates to a cartridge case (1), the hardness (H) of which varies in the axial direction (A). Traceability of the cartridge case is made possible in a simple way by producing the varying hardnesses (H) of the cartridge case (1) at least in one section of the cartridge case (1) in accordance with a hardness code (2).

Description

[0001] Method for manufacturing a cartridge case and cartridge casing

[0002] The invention relates to a method for manufacturing a cartridge case with the features of the preamble of claim 1 and a cartridge case with the features of the preamble of claim 9.

[0003] In prior art processes for manufacturing cartridge cases, varying hardness is produced in the axial direction of the cartridge cases. This occurs, for example, when the cartridge cases are deep-drawn or extruded from blanks, resulting in axial variations in the hardness of the manufactured cartridge cases. This variation in hardness is also due, in particular, to inaccuracies in the process control.

[0004] US Patent 11,465,207 B2 describes a metal die-casting process for manufacturing a cartridge case. This cartridge case, also manufactured using a die-casting process, exhibits a hardness gradient in the axial direction, which varies within a relatively wide tolerance range. If the cartridge case's hardness falls within this tolerance range, it is functional and thus meets the underlying quality requirements.

[0005] US patent 20130180392 A1 discloses another method for manufacturing a cartridge case. Here too, the cartridge case exhibits a hardness profile in the axial direction after its manufacture, which varies within a tolerance band.

[0006] The cartridge cases produced in this way are not traceable. However, the traceability of cartridges, such as small-caliber ammunition, has become an important issue in recent years in non-governmental organization (NGO) circles, security circles, and especially regulatory circles. Cartridges are also referred to as ammunition in this document. Given the global proliferation of firearms / weapons, especially small arms, and their ammunition, the question arises as to how this ammunition can be traced, for example, to uncover illegal trade flows and / or facilitate law enforcement. The problem is that small-caliber ammunition is currently not marked, which makes tracing very difficult. NGOs and joint governmental organizations (GGOs) are therefore calling for technologies and, above all, legislation to increase the transparency and traceability of small-caliber ammunition. Illegal trade routes for small-caliber ammunition do exist.Some of the small-caliber ammunition that ends up in conflict zones and in the hands of criminal organizations originates from illegal sources. Traceability could help uncover the origin and trafficking routes of this ammunition and then disrupt these routes. In criminal investigations, the origin of the ammunition can often provide crucial clues for solving a case. Clear marking and traceability allow governments, for example, to better control who buys, sells, or exports ammunition, thereby ensuring that it does not fall into the wrong hands.

[0007] Various methods of marking ammunition during its manufacture are known in the prior art, such as chemical or biological marking, marking with agents like gadolinium, marking by mechanical imprinting, marking with lasers or other focused thermal energy, and / or electrotechnical marking, e.g., using RFID tags. However, these methods of marking ammunition are sometimes very complex and only feasible with considerable effort and expense. Furthermore, depending on the nature of the marking, in some cases, it can lead to a loss of the weapon's effectiveness, for example, its accuracy. Electrotechnical solutions, in particular, have reliability issues, especially due to the destruction or damage of the marking during firing. Other markings can also be destroyed or damaged by firing.Other problems that have prevented any of the aforementioned solutions from becoming established include, for example, their lack of general acceptance, their lack of interoperability, limited reach of the technologies, lack of connections via appropriate databases, data protection or other regulations, the low added value in operational application, and a lack of doctrinal foundations.

[0008] The invention is therefore based on the objective of designing and / or further developing the method for manufacturing the cartridge case and the cartridge case itself in such a way that the problems of the prior art are avoided or at least reduced. In particular, traceability of the cartridge case should be made possible in a simple manner.

[0009] This problem underlying the invention is initially solved by a method for manufacturing a cartridge case with the features of claim 1. One aspect of the invention essentially lies in the fact that the varying hardness of the cartridge case is generated, at least in one section of the cartridge case, according to a hardness code.

[0010] Using a hardness code, information invisible to the human eye, such as that of a shooter, can be integrated into the cartridge case. If necessary, the hardness code can be read using specialized testing equipment, such as microhardness testers, for forensic analysis. The hardness code represents a preferably individual marking of the cartridge cases. The hardness code can be integrated into the cartridge case manufacturing process with minimal additional effort. Specifically, no additional process steps are required to generate the hardness code; the existing process steps simply need to be carried out in a specific manner. The hardness code cannot be removed from the cartridge case without destroying or rendering it unusable. The hardness code enables simple traceability of the cartridge case back to its manufacturer.The hardness code represents a type of identification code and can be converted into a string of characters, such as a numerical code. Such a string is particularly easy to process digitally and can be compared with existing information. In particular, the hardness code is a binary code, which is especially easy to generate and read because only two different states need to be created and retrieved.

[0011] Advantageously, the hardness code integrates information about the manufacturing date, batch, customer, packaging pallet, and / or ammunition box of the cartridge case. In particular, the hardness code can be assigned to this information. Such an assignment is preferably made via appropriate databases. The information is first converted into the desired hardness code, which is then generated during the manufacturing of the cartridge case.

[0012] Preferably, the varying hardness is achieved using a servo press. The speed of a die and / or a punch of the servo press, in particular the relative speed between the die and the punch, is then controlled and / or regulated depending on the desired hardness code. The work hardening of the material during forming is used to manufacture the cartridge case. Using the servo press, the cartridge cases are preferably produced for small-caliber ammunition in deep drawing and / or reverse extrusion processes. In this way, the cartridge case can be produced from a blank, in particular a disc, with only a few intermediate annealing cycles. The speed of the die and / or punch, in particular the relative speed between the die and the punch, can be adjusted very precisely, so that an easily readable hardness code can be generated.

[0013] According to a further embodiment of the method, the friction between the die and the punch of the servo press, and thus the hardness of the cartridge case, is controlled and / or regulated by varying the speed of the die and / or the punch, in particular the relative speed between the die and the punch. Friction is used as a parameter for control and / or regulation especially when materials with highly variable coefficients of friction, such as brass, are used to manufacture the cartridge case. Particularly in edge regions, the deformation and thus the hardness of brass is strongly dependent on the coefficient of friction. The greater the friction between the die and the punch, the harder the surface becomes at the respective point on the cartridge case.

[0014] According to a further preferred embodiment of the method, a higher relative speed between the die and the punch is set to achieve areas of lower hardness than to achieve areas of higher hardness. The advantage here is that a lower coefficient of friction is achieved at a higher relative speed.

[0015] It can be advantageous to set a more uniform relative speed between the die and the punch to achieve areas of lower hardness than to achieve areas of higher hardness.

[0016] In a particularly preferred embodiment of the method, an individual displacement-time profile is used to control and / or regulate the servo press. It is also conceivable that the die and / or the punch are temporarily stopped at corresponding holding positions, so that a relative velocity of zero is achieved between the die and the punch. The desired hardness code is converted into the individual displacement-time profile before the method is executed. The aforementioned dependencies between hardness and relative velocity between the punch and die come into play here.

[0017] Preferably, the varying hardness is achieved by heat-treating the cartridge case, in particular by laser annealing and / or induction heating. The heat treatment creates, or at least influences, the varying hardness of the cartridge case in at least one section according to the hardness code. This improves the readability of the hardness code.

[0018] The problem underlying the invention is also solved by a cartridge case with the features of claim 9.

[0019] One aspect of the invention essentially lies in the fact that the hardness varies in the axial direction, at least in one section of the cartridge case, according to a hardness code.

[0020] The hardness code integrates information invisible to the human eye, such as a shooter, into the cartridge case. If necessary, the hardness code can be read using specialized testing equipment, such as microhardness testers, for forensic analysis. The hardness code represents a preferably unique marking of the cartridge case. It cannot be removed from the cartridge case without destroying or rendering it unusable. The hardness code enables simple traceability of the cartridge case back to its manufacturer.

[0021] In a preferred embodiment of the cartridge case, the varying hardness of the hardness code lies between an upper and a lower limit. Thus, despite the hardness code, the functionality of the cartridge case is ensured. The cartridge case possesses the properties necessary for its function despite the hardness code.

[0022] Advantageously, the hardness varies across the inner wall of the cartridge case according to the hardness code. If the hardness only varies across the inner wall of the cartridge case according to the hardness code, the properties of the cartridge case are only minimally affected by the hardness code.

[0023] Furthermore, it is preferable for the hardness to vary across the entire wall thickness of the cartridge case according to the hardness code. This makes the hardness code easier to read, especially from the outside of the cartridge case.

[0024] Ideally, the hardness code provides information about the manufacturing date, batch, customer, packaging pallet, and / or ammunition box of the cartridge case, or the hardness code can be linked to this information. This allows for the easy detection and prevention of illegal trade routes for ammunition containing the cartridge case. It also enables better control over who buys, sells, or exports ammunition, thereby facilitating its prevention from falling into the wrong hands.

[0025] There are now numerous possibilities for advantageously designing and further developing the method for manufacturing the cartridge case and the cartridge case itself. Reference is made here to the claims subordinate to claims 1 and 9. In the following, a preferred embodiment of the inventive method for manufacturing the cartridge case and the cartridge case according to the invention will be explained and described in more detail with reference to the drawing and the accompanying description. The drawing shows:

[0026] Fig. 1 schematically represents a servo press for carrying out a method for

[0027] Manufacturing a cartridge case at the beginning of this process,

[0028] Fig. 2 shows a schematic representation of a cartridge case in a side view in section.

[0029] Figure 1 shows a device for carrying out a method for manufacturing a cartridge case 1. The cartridge case 1 produced by the method is shown in Figure 2. Varying hardnesses H are generated in the axial direction of the cartridge case 1. The hardness H is represented in particular by a curve in the diagram shown above the cartridge case 1. Furthermore, different areas of varying hardness H are shown on the cartridge case 1 itself, where areas of "high" hardness H are symbolized by dotted areas, and where the areas of "high" hardness H correspond to the hardness curve H. Areas of the same hardness H are formed in a ring shape with respect to an axis of the cartridge case 1.

[0030] The varying hardness H of the cartridge case 1 is generated in at least one section of the cartridge case 1 according to a hardness code 2. The hardness code 2 is formed by the characteristics of the areas of different hardness H, in particular their widths and / or their arrangement relative to each other. The hardness code 2 is preferably designed as a binary identification code. The hardness H then only needs to have two states, namely a "high" hardness H and a "low" hardness H, whereby these two states are converted into zeros and ones during the reading process. The "high" hardness H is greater than a medium hardness H. The "low" hardness H is less than the medium hardness H. The medium hardness H can vary in the axial direction A; in particular, the medium hardness H decreases towards the case mouth.In particular, a system similar to that used in barcodes can also be used for encoding, where an area of ​​"high" hardness H represents a black line or a space between two black lines.

[0031] The hardness code 2 integrates information about the manufacturing date, batch, customer, packaging pallet, and / or ammunition box of the cartridge case 1, or the hardness code 2 can be assigned to this information. This information is preferably converted into the hardness code H, or the parameters necessary for generating the hardness code H for the device used to carry out the process for manufacturing the cartridge case 1, by means of an automated process, namely by executing corresponding program code.

[0032] The varying hardness H is produced by means of a servo press 3 shown in Fig. 1. The device for carrying out the method for manufacturing the cartridge case 1 is therefore preferably designed as a servo press 3. The speed of a die 4 and / or a punch 5 of the servo press 3 is controlled and / or regulated depending on the desired hardness code 2. The punch 5 is movable towards and away from the die 4, in particular upwards and downwards, as symbolized by the double arrow in Fig. 1. A blank R arranged between the die 4 and the punch 5 is pressed into the die 4 by moving the punch 5 in the direction of the die 4 and is thereby plastically deformed according to the inner contour of the die 4 and the outer contour of the punch 5. When the desired shape of the blank R is achieved, the cartridge case 1 is produced from this blank R.Then the punch 5 is moved out of the die 4 and the cartridge case 1 is removed from the die 4 for further processing.

[0033] This manufacturing process places high demands on the material for the cartridge case 1, particularly on its formability. The case material for small-caliber ammunition is brass in the vast majority of cases. However, the use of other materials such as steel is also conceivable. Brass has proven itself as a material for cartridge cases 1 because, on the one hand, it dissipates heat well after firing, is easily formable due to its high coefficient of deformation, and on the other hand, exhibits good sealing behavior in a firearm during firing. This means that the seal between the chamber of the firearm and the cartridge case 1 is reproducible and reliable due to the expansion of the cartridge case 1. Furthermore, brass does not require corrosion treatment and, due to the low coefficient of friction between the cartridge case 1 and the chamber, can be easily extracted from and inserted into the chamber of fully automatic firearms.One partially negative property of brass is that it cannot be hardened by heating like steel, for example. Brass can only be hardened by deformation as described above and restored to its initial hardness by heating. Another property often perceived as negative is the coefficient of friction of brass, which is highly speed-dependent between a steel production tool, such as the punch 5 and die 4 of the servo press 3, and the brass blank R. During the manufacturing process, areas with a high degree of deformation therefore harden, while areas with a low degree of deformation remain close to their initial hardness.Since the hardness H also reflects the load-bearing capacity, in particular the yield strength, of the cartridge case 1, and high hardness H corresponds to high load-bearing capacity, the mechanical requirements for specific zones of the cartridge case 1 during firing, transport, or insertion into the firearm can be simulated within certain limits. In other words, after its manufacture, the cartridge case 1 exhibits hardness and / or strength adapted to the subsequent stresses.

[0034] The friction between the die 4 and the punch 5 of the servo press 3, and in particular the material for the cartridge case 1, and thus the hardness H of the cartridge case 1, is controlled and / or regulated by varying the speed of the die 4 and / or the punch 5. For this purpose, a relationship between this friction and the relative speed between the die 4 and the punch 5 in the servo press 3, namely a control device of the servo press 3, is defined in the form of a characteristic map and / or a formula.

[0035] To achieve areas of lower hardness H, a faster relative speed between the die 4 and the punch 5 is set than to achieve areas of higher hardness H. This takes into account the special properties of brass, ensuring that precisely formed hardness codes H are achieved, particularly in cartridge cases 1 made of brass.

[0036] To achieve areas of lower hardness H, a more uniform relative speed is set between the die 4 and the punch 5 than to achieve areas of higher hardness H.

[0037] An individual displacement-time profile is used for controlling and / or regulating the servo press 3. This displacement-time profile is present in the servo press 3, namely in a control unit of the servo press 3, or is generated by the servo press 3, in particular its control unit, based on the desired information to be integrated into the hardness code 2.

[0038] The varying hardness H is produced by means of a heat treatment of the cartridge case 1 not shown here, in particular laser annealing and / or inductive tempering, or at least is changed after the manufacture of the cartridge case 1 by means of the servo press 3 to achieve or specify the hardness code 2.

[0039] The hardness H of the cartridge case 1 shown in Fig. 2, which is produced using the previously described method, varies in the axial direction A. The hardness H varies at least in one section of the cartridge case 1 according to the hardness code 2 in the axial direction A.

[0040] The varying hardness H of hardness code 2 lies between an upper limit O and a lower limit U. The aforementioned average hardness H lies midway between the upper limit O and the lower limit U. The upper limit O and the lower limit U represent the tolerance band within which the hardness H of the cartridge case 1 must lie to ensure its proper function.

[0041] The hardness H varies at least in the area of ​​an inner wall 6 of the cartridge case 1 according to the hardness code 2. In particular, the interface between the moving punch 5 and the case material is relevant for generating the hardness code 2. Specifically, the cartridge case 1 can then also exhibit varying hardness H perpendicular to the axial direction A, namely a different hardness H on the outer wall than on the inner wall 6 at the same axial position.

[0042] The hardness H preferably varies over the entire wall thickness of the cartridge case 1 according to the hardness code 2. In particular, the cartridge case 1 then exhibits the same hardness H perpendicular to the axial direction A.

[0043] The hardness code 2 contains information about the manufacturing date, batch, customer, packaging pallet, and / or ammunition box of the cartridge case 1, or the hardness code 2 can be assigned to this information. Appropriate databases are provided for comparing this information, particularly for the aforementioned assignment. Specifically, a data link between the servo press 3, especially its control unit, and such databases for information exchange has been implemented. This allows for the simple traceability of small-caliber ammunition with such cartridge cases 1.

[0044] Reference symbol list

[0045] 1 cartridge case

[0046] 2 Hardness code

[0047] 3 servo press

[0048] 4 die

[0049] 5 stamps

[0050] 6 Interior wall

[0051] R blank

[0052] A Axial direction of the cartridge case 1

[0053] H Hardness of the cartridge case 1

[0054] O upper limit

[0055] U lower limit

Claims

Patent claims 1. Method for manufacturing a cartridge case (1) wherein varying hardnesses (H) of the cartridge case (1) are produced in the axial direction (A) of the cartridge case (1), characterized in that the varying hardnesses (H) of the cartridge case (1) are produced at least in one section of the cartridge case (1) according to a hardness code (2).

2. Method according to claim 1, characterized in that information about a manufacturing time, a batch, a customer, a packaging pallet and / or an ammunition box of the cartridge case (1) is integrated into the hardness code (2) or that the hardness code (2) can be assigned to this information.

3. Method according to claim 1 or 2, characterized in that the varying hardness (H) is produced by means of a servo press (3), wherein the speed of a die (4) and / or a punch (5) of the servo press (3) is controlled and / or regulated depending on the desired hardness code (2).

4. Method according to claim 3, characterized in that the friction between the die (4) and the punch (5) of the servo press (3) and thus the hardness (H) of the cartridge case (I) is controlled and / or regulated by varying the speed of the die (4) and / or the punch (5).

5. Method according to one of claims 3 or 4, characterized in that to achieve areas of lower hardness (H) a faster relative speed is set between the die (4) and the punch (5) than to achieve areas of higher hardness (H).

6. Method according to one of claims 3 to 5, characterized in that to achieve areas of lower hardness (H) a more uniform relative speed is set between the die (4) and the punch (5) than to achieve areas of higher hardness (H).

7. Method according to one of claims 3 to 6, characterized in that an individual path-time profile is used for controlling and / or regulating the servo press (3).

8. Method according to one of the preceding claims, characterized in that the varying hardness (H) is produced by means of a heat treatment of the cartridge case (1), in particular laser annealing and / or inductive tempering.

9. Cartridge case (1), which is produced in particular by means of a method according to one of claims 1 to 8, wherein the hardness (H) of the cartridge case (1) varies in the axial direction (A), characterized in that the hardness (H) varies at least in a section of the cartridge case (1) according to a hardness code (2) in the axial direction (A).

10. Cartridge case (1) according to claim 9, characterized in that the varying hardness (H) of the hardness code (2) lies between an upper limit (O) and a lower limit (U).

11. Cartridge case (1) according to claim 9 or 10, characterized in that the hardness (H) in the area of ​​an inner wall (6) of the cartridge case (1) varies according to the hardness code (2).

12. Cartridge case (1) according to one of claims 9 to 11, characterized in that the hardness (H) varies over the entire wall thickness of the cartridge case (1) according to the hardness code (2).

13. Cartridge case (1) according to one of claims 9 to 12, characterized in that the hardness code (2) contains information about a manufacturing time, a batch, a customer, a packaging pallet and / or an ammunition box of the cartridge case (1) or that the hardness code (2) can be assigned to this information.

Images