SE2300025A1 - Wedge - Google Patents

Abstract

The present invention relates to a method for producing a wedge (1) for an ejection device, where the method comprises that a raw material for the wedge (1) is manufactured from at least two different metal powders, a bulk material (20) and a surface capsule (10), so that the surface capsule (10) is arranged to enclose the bulk material (20), and where the surface capsule (10) is manufactured additively, after a raw material for the wedge (1) has been manufactured, the raw material is post-processed for the production of the wedge (1). The invention further relates to a wedge and to an ejection device comprising a wedge.

Description

WEDGE FOR LAUNCH DEVICE AND METHOD FOR MANUFACTURE OF WEDGE FOR LAUNCH DEVICE TECHNICAL FIELD The present invention relates to a method for producing a wedge for a launch device, where the method comprises that a raw material for a wedge is manufactured from at least two different metal powders, a bulk material and a surface coating, so that the surface coating arranged to enclose bulk material, and the surface coating is manufactured additively, after a raw material until the wedge has been manufactured, the raw material is further processed for the production of the wedge. The invention further relates to a wedge and a projecting device including a wedge.

BACKGROUND OF THE INVENTION, PROBLEM STATEMENT AND PRIOR ART Launchers, such as tube-based weapons, are fired by burning gunpowder and thereby creating a gas expansion where the gas expansion moves a projectile in a tube. Wedge mechanism is a common mechanism for launchers such as a cannon, especially automatic cannons. A central component of the wedge mechanism is a nearly rectangular block of metal, also called a wedge, which can slide in a groove in the ejection device, the rear part of the piece, perpendicular to the longitudinal axis of the firing tube. By operating the wedge perpendicular to the firing tube, an opening to the chamber of the firing tube can be created so that an ammunition unit can be arranged in the chamber, after which the wedge can be maneuvered so that it is arranged behind the ammunition unit and thus locks the ammunition unit in the firing tube, after which the ammunition unit can be fired. Preferably, a striker is arranged in the wedge which can hit an igniter arranged in the ammunition unit which initiates the propellant charge in the ammunition unit. The wedge design allows for a high rate of fire, but it is not gas-tight which means that the propellant charge_must be enclosed in a case. When the piece is to be loaded, the wedge is pushed aside by hand or machine power and an ammunition unit is inserted into the chamber. In a common embodiment, the sleeve of the ammunition unit hits ejectors which are arranged on both sides of the cartridge position/chamber and this releases a latch so that the wedge closes. If the zoza -na-gig ammunition unit is fired, the wedge mechanism is opened again, usually with the help of the recoil force. The mechanism is designed so that the wedge pushes the ejectors backwards as it slides away so that the empty case is ejected. The process can then be initiated again so that an autocannon can be provided which repeatedly, in succession, fires ammunition units. Each ammunition unit is arranged with a projectile and propellant arranged in a sleeve. In the sleeve, an ignition device is arranged and includes an ignition cap that can ignite the propellant charge. As an alternative to an ignition cap, the propellant charge can be ignited with, for example, an electrical pulse or with a laser.

Examples of manufacturing methods for wedges or other end piece components are given in patent document CN 110893 503 A, which describes a method for manufacturing components through an additive manufacturing method including arc welding.

The above known technology does not demonstrate that additive manufacturing methods including powder are used.

Further problems which the present invention intends to solve appear in connection with the following detailed description of the various implementations. received at the Patent and Regulatory Agency; 2923 =aíl3~ MB THE PURPOSE OF THE INVENTION AND ITS CHARACTERISTICS The purpose of the present invention is to achieve an improved way of manufacturing a wedge consisting of at least two different metals where a core, of a metal with certain properties, is coated with another metal adapted to cooperate with other metal components included in the ejection device.

The invention relates to a method for producing a wedge for a launch device, where the method includes that a raw material for the wedge is manufactured from at least two different metal powders, a bulk material and a surface capsule, so that the surface capsule is arranged to enclose bulk material, and where the surface capsule is manufactured additively, after a raw material until the wedge has been manufactured, the raw material for the production of the wedge is post-processed.

According to further aspects for the method of producing a wedge according to the invention apply; a t t bulk material is additively arranged in raw material to wedge. that bulk material is arranged in a surface capsule in powder form after the surface capsule has been produced additively. that post-processing of the raw material involves subjecting the raw material to high pressure and heat, also known as Hot Isostatic Pressing, HIP, for pressing and sintering the metal powders included in the raw material. a t t finishing further, after Hot Isostatic Pressing, includes heat treatment. a t t finishing further, after Hot Isostatic Pressing and heat treatment, includes mechanical processing of the wedge. that the surface capsule preferably consists of low-alloy NiCrMo' steel.

Inkorn to the Patent and Registration Office 2023 -ua- sin A low-alloy NiCrMo steel characterized by high strength and high hardness. The high hardness is needed as a result of abrasion that occurs during firing and high strength to resist plastic deformation. As the surface layer has such a high strength, properties such as ductility and toughness will be affected. Instead, the material will be somewhat brittle. Therefore, a tough core is needed, as in the bulk material, of a more alloyed steel, e.g. tool steel or martensitic stainless steel.

The low-alloy NiCrMo steel has a yield strength of a minimum of 1200 MPa and an impact toughness at - 40 C of a minimum of 27 J. a t t the bulk material preferably consists of stainless steel or tool steel. The stainless steel or tool steel has higher levels of Cr and Ni than the low-alloy carbon steel used at the surface. The core, the bulk material, must consist of a lower alloy steel, e.g. a tool steel with higher levels of Cr and Ni than the low-alloy carbon steel used at the surface. A risk with HIP is that every grain in the metal before HIP can oxidize and then lead to properties for toughness and fatigue being lowered as the oxides of each grain lead to natural crack growth paths. Therefore, steels (stainless steels/tool steels) with higher levels of Chromium are used as they form chromium oxide and counteract this. The core material must be stainless or a tool steel and characterized by properties such as good fatigue strength, toughness and ductility. Materials that can be used are, for example: Stainless martensitic steels; X4CrNiMo16-5-1 (1.4418), Super 13 Cr (UNS S41426) Tool steel: X40CrMoV5-The stainless steel or tool steel has a yield strength of about 800-900 MPa and an impact strength at - 40 C of 50 J minimum.

The invention further consists of a wedge.

The invention further consists of a push-out device comprising a wedge.

ADVANTAGES AND EFFECTS OF THE INVENTION Received at the Patent and Registration Office 2823 -Ûåe 311] By manufacturing parts of the wedge or the entire wedge through additive manufacturing, it is possible to achieve a wedge with higher strength and toughness compared to currently existing technology which is based on cutting processing of a forging material. For future launch systems, where both the rate of fire and the forces acting on the wedge are expected to increase, new manufacturing solutions for the wedge are required to improve the wedge's properties. LIST OF FIGURES The invention will be described in more detail below with reference to the attached figures where: Fig. 1 shows a wedge in cross section, according to an embodiment of the invention.

Fig. 2 shows the method steps for manufacturing a wedge, according to an embodiment of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS The present invention shows embodiments of manufacturing methods for improved launch device wedge.

A launching device, also called a cannon, howitzer, or piece, such as an automatic cannon, is intended to release a projectile by means of a propellant. Preferably, a propellant, such as gunpowder, is initiated in a part of the cannon, often a chamber specially adapted for this. For the automatic cannon, the propellant is preferably arranged in a sleeve. Initiation takes place by igniting the propellant, for example with an ignition cartridge or an igniter in an ammunition unit, which is initiated by impact. Other methods of igniting the propellant may be by laser or electrical energy igniting the propellant. The propellant burns at high speed and large gas evolution, which creates a gas pressure in the chamber that propels the projectile out of the fire tube of the launch device. The propellant is adapted to, to the greatest extent possible, generate a constant pressure on the projectile during the entire course of the fire tube, when the projectile moves in the fire tube, which creates a high speed of the projectile when the projectile enters the mouth of the fire tube . For automatic guns arranged to fire ammunition units, the projectile, igniter and the propellant are arranged in a sleeve. Because the propellant is arranged in a sleeve, a simpler mechanism, often called a wedge, can be used to seal behind the ammunition unit when the ammunition unit is arranged in the chamber of the firing tube. The wedge does not close gas-tight against the firing tube, which enables a high rate of fire, that is, ammunition units can be exchanged at high speed by opening the wedge and enabling an ammunition unit to be fitted to the firing tube and then move the wedge so that it closes to the firing tube, after which the projectile is fired from the ammunition unit, after which the empty sleeve is removed to then once again arrange an ammunition unit to the firing tube.

Projectiles, such as different types of grenades, in most cases include some form of action part and some form of fuze that initiates the action part. Firing tubes can be of different types where impacts are common for projectiles that intend to detonate on contact with an object, time tubes when the projectile intends to detonate at a certain predetermined time and zone tubes when the projectile intends to detonate when an object comes within a certain distance of the projectile. Zone tubes are preferably used when combating aircraft and usually for medium-caliber ammunition, for example 40 mm and 57 mm, while time tubes and targets can be used when combating a large number of different objects. Advantageously, different types of fuze function are combined in the same fuze, so that if a fuze with zone fuze function does not detect an object, the projectile breaks after a certain time, etc.

The effective part preferably includes some form of explosive substance and some form of shrapnel-like casing that encloses the explosive substance. Furthermore, various forms of control means, such as fins, can be arranged either in the fuze or in a separate sub-component.

In order to stabilize the projectiles after the projectiles have left the fire tube, the projectiles are preferably arranged with rotation alternatively with fins. In the case that the projectiles are arranged with rotation, the projectiles are said to be rotationally stabilized and in the case that the projectiles are arranged with fins, the projectiles are said to be fin stabilized.

Fin-stabilized projectiles should have no rotation or low rotation as they leave the barrel.

Received at the Patent-oct registration office 72% ellïlf" In order to achieve rotation of the projectiles, grooves are often arranged in the barrel to which the projectile connects during the firing process. Grooving means that the barrel in a firearm, the barrel, is provided with spiral grooves. The opposite is a smooth bore barrel.

When the grooves engage the projectile during firing, the projectile undergoes a rotation along its longitudinal axis. Through the rotation, minor irregularities or damage to the projectile will not cause a drift in the trajectory of the projectile. Rotation is also necessary in order for an oblong (torpedo-shaped) projectile to maintain its direction after it leaves the barrel and not start tumbling around, this is called the projectile being rotationally stabilized. In smoothbore weapons, only round (spherical) projectiles or fin-stabilized projectiles can be fired. An elongated projectile without fins will tumble as it leaves the muzzle.

Grooves are thus grooves arranged in the barrel of the fire tube, and the elevation between them is called booms. Typically, the rifling of fine-caliber firearms consists of four right-handed rifling, while cannons, such as artillery pieces, have a greater number of rifling depending on the caliber of the launcher. In order for the fluting to be able to engage the projectile, the projectile must either be slightly larger than the diameter between the booms, which is common for small caliber weapons, or be fitted with a special flange, called a girdle, which has a slightly larger diameter than the booms, which is common occurring in projectiles with a diameter greater than 20 mm. The girdle can be made of plastic, composite material or a soft metal, such as copper or a copper alloy. The length of the barrel on which the rifle rotates a full turn is called pitch and is usually given in inches per revolution. Most barrels include ribbing, and by arranging projectiles with sliding belts, both rotationally stabilized and fin-stabilized projectiles can be fired with rifled barrels. Smooth bore fire tubes are in principle only used for weapon systems intended to fight armored combat vehicles as the rotation of the projectile means that the directed blast effect, RSV, works worse because the centrifugal force causes the beam to spread out.

If wedges, or other parts for projecting systems, are manufactured with HIP, materials with high resistance to impact loads can be produced. Shock loads are part of the recoil forces that arise in a launch system when projectiles are fired from a lkøm to the Patent and Registration Office 2023 -ÛllFeldrør. It is desirable to provide a wedge with higher strength and toughness compared to currently existing technology. Since the wedge is part of the mechanism in an ejection system, material compatibility between the components included in the ejection system is assumed. If, for example, the wedge is changed to a different material than the other components in the ejection system, there is a risk that corrosion may occur, for example if the quality varies between the components included in the ejection system. In particular, there are risks of corrosion for pieces in a marine environment as a conductive liquid, such as salt water, can act as a conductive liquid that can cause galvanic corrosion of the components included in the piece if the material/grade between the components differs. It is therefore relevant that an improved wedge has a surface coating with similar material properties as surrounding components in the launch system as the wedge will be close to other components in the launch system and will also be exposed to salt water.

Through additive manufacturing of a wedge based on two different metal powders, where the metal powders have different properties, an improved wedge can be created. Preferably, a wedge is created with a bulk substance in the core and a substance as a surface layer where the additively manufactured component undergoes Hot Isostatic Tarpaulin to eliminate pores in the part. In a first embodiment, the raw material for the wedge is manufactured from an outer capsule that is manufactured additively, which is then filled with metal powder in the core. In a second embodiment, the raw material for the entire wedge is additively manufactured from two metal powders.

In the case that an outer capsule, the surface capsule, is manufactured additively, filling and packing can be done by hand from the metal powder that is arranged in the core, the bulk material, inside the outer layer, the surface capsule. The outer layer is manufactured additively, preferably with 3D Printing, as the outer geometry of the wedge is too complex to manufacture as is usually done with HIP, i.e. pressing of sheet metal and welding. After 3D Printing of the outer geometry, the capsule, the capsule is filled with powder in an opening arranged in the surface capsule. The opening is preferably arranged in a position on the wedge where external stresses on the wedge are small. Then the HIP process is started with evacuation, vibration and sealing of the capsule construction. Then HIP in oven.

Hot isostatic pressing, HIP (in English Hot Isostatic Pressing), is a manufacturing process to control grain size and structure in the material. HIP lnkorn to the Patent and Trademark Office zßzs an» also enables the packing of metal, polymer, ceramic and composite powders into solid form. The benefits include removing all internal voids in metal components created by additive manufacturing methods so that mechanical properties, such as fatigue resistance, toughness, plasticity and impact strength, are improved. Furthermore, HIP can create a dense material from metal, composite, polymer or ceramic powder without melting and that materials with partly different characteristics can be coordinated in the same component.

With HIP, a solid material with superior properties can be created from powder as powder/powder components have a fm, uniform grain size and isotropic structure. Furthermore, through the use of HIP, dissimilar metals can be joined without the need for temperature-limiting binders. Through HIP, several diffusion bonds can be created in a single process cycle. HIP works for a large number of metal alloys, as well as for example polymers and ceramic materials. For example alloys with nickel, cobalt, tungsten, titanium, molybdenum, aluminium, copper and iron, oxide and nitride ceramics, glass, intermetallic substances and polymers. HIP enables bonding and combinations of materials that cannot otherwise be combined, i.e. composites.

After the bi-material part has undergone hot isostatic pressing, various forms of annealing can be carried out to change the mechanical properties of the wedge. After heat treatment, if necessary, surface processing can be carried out such as cutting processing or grinding of the part to adapt the part based on adaptation to the extension system. Additive manufacturing, like various forms of 3D-Printing, can be carried out where one material is chosen for a surface layer and another material is chosen for the core, the bulk material.

The material for the surface layer preferably consists of low-alloy NiCrMo carbon steel, i.e. a steel with a lower percentage of alloying elements, with the same or similar chemical composition as adjacent parts (back piece and fire tube). By choosing a steel quality with similar properties to other details in the firing system, good material compatibility can be achieved. The core, the bulk material, consists of a different material with different properties adapted to better resist the forces acting on the wedge of recoil. lnkorn to the Patent and Regulatory Agency 2023 -na- w A number of different methods for additive manufacturing are considered relevant such as - Electron Beam Melting (EBM) - Direct Laser Metal Sintering (DMLS).

With Electron Beam Melting, EBM, the part is manufactured layer by layer in a vacuum chamber and uses an electron beam to melt metal powder fed from a holder/cassette, and distributed/spread on a platform/coordinate table. The electron beam then ignites the metal powder and melts the metal powder to complete a part, also called blank. Relatively high temperature is created by the electron beam, which melts the metal powder in the focal point of the electron beam. By distributing the material/melting the material based on a CAD model, a detail with great freedom regarding geometric structure can be created, furthermore, several metal powders can be used for the creation of a detail consisting of several different materials. The detail is built layer upon layer.

With Direct Laser Metal Sintering, DMLS, the part, also called raw material, is manufactured by heating one or more different powder materials and spreading them out in an even layer over a flatbed/coordinate table with a roller, after which a pulsed laser irradiates selected parts of the powder material where a cross-section can be created by the powder particles, through the heat generated by the lasem, adhere to each other and form a detail. The layer thickness is 0.1 mm and powder that does not become part of the detail can be reused.

In fig. 1 shows a wedge 1 in cross-section where a bulk material 20 of preferably stainless powder steel such as a martensitic steel and a surface capsule 10 of preferably low-alloy carbon steel. The bulk material 20 preferably has material properties that result in high toughness and maintained or slightly lower strength when the stresses are highest in the surface. The contact surface between the bulk material 20 and the surface capsule 10 is a diffusion bond that is created with Hot Isostatic Pressing of the powder component/raw material. The additively manufactured component, the raw material, is arranged in an oven preferably arranged with connection device for evacuation of air, vacuum pumping, before and/or during the implementation of the manufacturing method in the form of Hot Isostatic Pressing. received at the Patent and Registration OfficeFig. 2 shows manufacturing method 100 for wedge 1 with HIP. Initially, a surface capsule is manufactured additively from a first metal powder in the step Surface capsule is manufactured additively from a first metal powder 101. One metal powder is used for the surface coating of the raw material, the surface capsule, and another metal powder is used for the bulk material, the core, of the raw material. The surface capsule is manufactured from powder with an additive manufacturing method, for example EBM or DMLS but also other currently available methods, and any future additive manufacturing methods can be used to manufacture the surface capsule. In the next step Raw material is produced by filling the surface capsule with a second metal powder 102, core material is arranged in the surface capsule, for example by filling and packing material by hand. Furthermore, the entire raw material can be manufactured additively from two metal powders, a first metal powder for the surface capsule, which constitutes the surface treatment, and a second material for the core, the bulk material. In step Evacuation, vibration, closure 103, the raw material can be prepared for the next step HIP. In the case that the raw material is manufactured completely additively, step 103 can be omitted so the raw material is already prepared for HIP. Hot isostatic pressing is then carried out in step HIP 104, that is to say that a gas is used to create an isostatic pressure on the raw material by arranging the gas to a connection device on the furnace. Before the gas is arranged for the oven, the oven can be vacuum-pumped or otherwise evacuated on air or the filling gas/fluid that is arranged in the oven before evacuation, for example by flushing with a noble gas. There, the entire raw material is heated for the creation of a preform or HIPPAD body. HIP temperature is preferably 20% below the melting temperature of the material, for martensitic stainless steels the HIP temperature is above the phase transformation to the austenitic state (which is on the order of 80% of the material's melting point). After hot isostatic pressing is carried out, the body can undergo heat treatment/hardening 106, which means that the now joined body is heated. After heat treatment, the material is suitable for processing, for example cutting processing in step Processing 108 where cutting processing such as turning or milling or grinding. Where applicable, a surface treatment 110 such as phosphating or manganese phosphating is also carried out as rust protection. ALTERNATIVE EMBODIMENTS Received at the Patent and Registration Office in 2023 -ua- that the invention is not limited to the specifically shown embodiments but can be varied in various ways within the scope of the patent claims.

It is understood, for example, that the choice of materials, the choice of geometric shapes, the elements and details included in the wedge or the components for the launch system are adapted to the weapon system(s), platform and other design features that are currently available.

Furthermore, all forms of wedges and end pieces for both fine caliber, medium caliber and coarse caliber are included.

Received at the Patent and Trademark Office 2823 ~ilfi~= Bli

Claims (10)

1. Method for the production of a wedge (1) for a launch device, characterized in that the method comprises that a raw material for the wedge (1) is manufactured from at least two different metal powders, a surface capsule (10) manufactured from a first metal powder and a bulk material (20) manufactured of a second metal powder, so that the surface capsule (10) is arranged to enclose bulk material (20), and where the surface capsule (10) is manufactured additively, after a raw material until wedge (1) has been manufactured, the raw material for the production of wedge (1) is post-processed. 2. Method according to claim 1, characterized in that bulk material (20) is added additively in raw material to wedge (1). 3. Method according to claim 1, characterized in that bulk material (20) is arranged in surface capsule (10) in powder form after the surface capsule (10) has been produced additively. 4. Method according to one of the above claims, characterized in that post-treatment of the raw material includes subjecting the raw material to high pressure and also called Hot Isostatic Pressing, HIP, for pressing and sintering the metal powders included in the raw material. 5. Method according to claim 4, characterized in that post-treatment further, after 6. Hot isostatic pressing, includes heat treatment. 6. Method according to one of claims 4 - 5, characterized in that further post-treatment, after Hot Isostatic Pressing and heat treatment, includes mechanical processing of the wedge. 7. Method according to one of the above requirements, characterized in that the material in the surface capsule preferably consists of low-alloy NiCrMo steel. 8. Method according to one of the above claims, characterized in that the bulk material preferably consists of stainless steel or tool steel. 9. Wedge (1) with higher strength and toughness manufactured according to any of claims 1 - 10. Ejection device arranged with a wedge according to claim 9.