WO2021048186A1

WO2021048186A1 - An arrangement and a method for manufacturing a ballistic armor

Info

Publication number: WO2021048186A1
Application number: PCT/EP2020/075168
Authority: WO
Inventors: Kari NEULANIEMI
Original assignee: Tactical Design And Testing Services Oy
Current assignee: Tactical Design And Testing Services Oy
Priority date: 2019-09-10
Filing date: 2020-09-09
Publication date: 2021-03-18
Anticipated expiration: 2022-03-10
Also published as: FI20197116A1; EP4028712A1; FI128695B

Abstract

The invention relates to an arrangement and a method for arranging armor elements into a casing. A problem in the prior art is the high accuracy requirement for dimensional tolerances of the casing. According to an embodiment of the present invention, an arrangement for manufacturing a ballistic armor comprises a casing comprising at least one cavity for a number of armor elements, feeding means for inserting armor elements into said cavity, and at least one forming device for providing at least one inner dimension of the cavity to a desired dimensional accuracy, wherein the forming device is arranged in the feeding means for forming at least a part of the cavity to a desired inner dimension before inserting armor elements into the cavity.

Description

AN ARRANGEMENT AND A METHOD FOR MANUFACTURING A BAL LISTIC ARMOR

Technical field Generally, the invention relates to an arrangement and a method for manufacturing a ballistic armor, and more particularly to an arrangement and a method for arranging armor elements into a casing.

Background technology Ballistic protection concerns protection against kinetic energy or pressure caused by projectiles such as bullets, gravity bombs, rockets etc... Ballistic armor works by de creasing the energy density of the projectiles, for example by affecting the shape or position of the projectile, by breaking the projectile and/or by decelerating the veloc ity of the projectile. Ballistic armor against pressure caused by ammunition works by absorbing or directing the energy of the shock wave.

A ballistic armor may be produced of almost any material when the mass is sufficient enough. However, especially land, sea and air vehicles benefit when the armor is as light as possible, and further when the armor works as the load bearing structure. Often there is also a requirement for the armor to fit into a small space, i.e. practically speaking the thickness of the structure needs to be as thin as possible.

Traditionally, metallic structures, for example High Hardness Steels have been used in the production of ballistic armors. However, the cores of some projectiles aimed for penetrating armors, i.e. the penetrator, have such a high hardness that the hardness of the metallic armor structures are insufficient to cause damage to these penetrators. Therefore, the armor structure in these cases works by absorbing the kinetic energy of the projectile. The armor structures intended against these penetrators become ex cessively massive as a monolithic metallic structure, especially when applied to ve hicles.

As known from prior art, ceramic elements and metallic ceramic composites, such as aluminum oxide (A1203), silicon carbide (SiC), boron carbide (B4C), tungsten car bide (WC), boron nitride (BN), silicon nitride (Si3N4), carbon nitride (C3N4), tita nium diboride (TiB2), may be used in ballistic armors. Such materials may have a hardness sufficient to generate damage to the projectiles. Ceramic materials are known to have high compressive strength, but at the same time weak tensile strength.

The simplest construction principle when using ceramic elements in a ballistic armor is gluing rectangular prism ceramic elements, such as bricks, to a frame structure, such as a fiber composite laminate. The manufacturing methods when using ceramics most often require piling the elements manually on a panel-shaped mold of the de sired final product, i.e. because the after treatment (for example cutting into shape) of the ceramic elements is difficult due to their high hardness. Typical armors that have ceramics glued to a frame structure do not withstand bending load. Therefore, such armors do not work as load-bearing structures in vehicles, for example. Instead, these armor structures form a structural parasitic weight (excessive weight).

According to prior art it is also known that ballistic armors may be improved by, either fully or partly, encapsulating ceramic elements. This is known to i) delay the fracturing of the ceramic surface and the start of the penetration ii) slow down the cracking of the ceramic element iii) keeping the ceramic material in contact with the penetrator and thus in creasing the erosion of the penetrator iv) affecting the fracturing and shaping of the ceramic elements caused by a shock wave with the adaption of the ceramic elements and the encapsulat ing material’s acoustic impedance.

Prior art tells that the shock resistance of ceramic elements increases significantly when molten metal, such as aluminum, is casted on top of the ceramic elements. The big difference in the ceramic elements’ and aluminium’s thermal expansion creates a compressing pretension for the ceramic elements when the molten metal cools down to solid material contracting at the same time.

The manufacturing complexity is a common characteristic for the presented struc tures. The known structures are also limited to a predefined shape. It has been difficult to adapt existing solutions to serial production as well. Even though there is a clear benefit due to the fact that the ceramic elements get a pretension when compressed by a metal casing, one disadvantage is that the existing methods require high accuracy for dimensional tolerances.

Document FI 20155776 describes a method for inserting armor elements to a casing structure comprising at least the steps of manufacturing a casing, and inserting armor elements in the cavities of the casing. One disadvantage of the method is the high accuracy requirement for dimensional tolerances of the casing.

Summary of the invention It is an objective of the present invention to implement such a solution, that the pre viously mentioned drawbacks of the prior art could be diminished. In particular, the invention is implied to solve how to easily arrange the inner dimensions of a cavity of a casing to a desired dimensional accuracy in connection with the assembly of armor elements. The objective of the invention is met by the features disclosed in the independent patent claims.

An arrangement for manufacturing a ballistic armor according to the present inven tion is characterized by the features of claim 1.

According to an embodiment of the present invention, an arrangement for manufac- turing a ballistic armor comprises a casing comprising at least one cavity for a number of armor elements, feeding means for inserting armor elements into said cavity, and at least one forming device for providing at least one inner dimension of said cavity to a desired dimensional accuracy, wherein said forming device is arranged in said feeding means for forming at least a part of said cavity to a desired inner dimension before inserting armor elements into said cavity.

In an embodiment, the feeding means comprises supporting means for aligning the forming device and/or armor elements from at least two sides with said cavity. In an embodiment, the feeding means further comprises inserting means, such as a pusher, for arranging the forming device and/or armor elements into said cavity. These em- bodiments may enable the movement of the forming device in relation to the cavity for forming it before inserting armor elements. These embodiments may also facili tate inserting armor elements to the cavity after the forming device.

In an embodiment, the forming device comprises one or more forming means, such as structures, shapes, blades and/or the combination thereof, arranged for forming said inner dimension of said cavity. Forming of the cavity can be performed in many ways, such as, but not limited to, by chipping, grinding and/or mangling, for example. In another embodiment, the arrangement further comprises at least one setting ele ment having at least one dimension differing from armor elements to be assembled for staggering the armor elements in different cavities. The material of the setting element may be the same as the armor elements or any other suitable material. This embodiment may enable staggering of the armor elements in such way that the seams of the armor elements are shifted. The embodiment may be useful especially in adja cent cavities for shifting the points of seams between one cavity preferably to the middle of the armor elements in the other cavity.

In an embodiment, the arrangement further comprises holding means for keeping said casing stationary. This embodiment enables the feeding means to insert the forming device and/or armor elements into the cavity of the casing.

In an embodiment, the arrangement further comprises heating means for providing at least partial thermal expansion of said casing. This embodiment may enable to form a stronger ballistic armor by utilizing the method of thermal expansion, which may give armor elements a pretension by compression, when cooling down.

A method for manufacturing a ballistic armor according to the present invention is characterized by the features of claim 8.

According to an embodiment of the present invention, the method for manufacturing a ballistic armor comprises at least the steps of:

- arranging at least one forming device in the feeding means before armor elements to be assembled; and

- pushing the casing and/or said forming device towards each other for forming at least a part of the cavity to a desired inner dimension before inserting armor ele ments into the cavity.

Some preferable embodiments of the invention are described in the dependent claims.

Significant advantages can be achieved with the present invention when compared to prior art solutions. The arrangement and the method of the present invention may provide a fast and easy way to arrange a cavity of a casing to a desired inner dimen sion.

It may be easy to use different kind of forming devices, if necessary, and in some embodiments, the feeding means of the present invention may enable to perform forming while inserting armor elements. The expression “a number of’ refers herein to any positive integer starting from one (1), e.g. to one, two, or three.

The terms “a” and “an”, as used herein, are defined as one or more than one.

As used herein, "plurality" means two or more. As used herein, a "set" of items may include one or more of such items. As used herein, whether in the written description or the claims, the terms "comprising", "including", "carrying", "having", "contain ing", "involving", and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases "consisting of' and "con sisting essentially of', respectively, are closed or semi-closed transitional phrases with respect to claims. Use of ordinal terms such as "first", "second", "third", etc., in the claims to modify a claim element does not by itself connote any priority, prece dence, or order of one claim element over another or the temporal order in which acts of a method are performed, but are used merely as labels to distinguish one claim element having a certain name from another element having a same name (but for use of the ordinal term) to distinguish the claim elements. As used herein, "and/or" means that the listed items are alternatives, but the alternatives also include any combination of the listed items.

Short description of the drawings Next, the invention is described in more detail with reference to the appended draw ings, in which

Fig. 1 depicts a top view of an exemplary embodiment of an arrangement according to the present invention for forming the inner dimension of a cavity and inserting armor elements, and Fig. 2 is a flowchart of an embodiment of a method according to the present inven tion for forming the inner dimension of a cavity and inserting armor elements.

Detailed description of the embodiments

Throughout this description, the embodiments and examples shown should be con- sidered as exemplars, rather than limitations on the apparatus and procedures dis closed or claimed. Although many of the examples presented herein involve specific combinations of method acts or arrangement elements, it should be understood that those acts and those elements might be combined in other ways to accomplish the same objectives. With regard to flowcharts, additional and fewer steps may be taken, and the steps as shown may be combined or further refined to achieve the methods described herein. Acts, elements and features discussed only in connection with one embodiment are not intended to be excluded from a similar role in other embodi ments.

In the Figures herein, unique features receive unique reference numerals, while fea tures that are the same in more than one drawing receive the same reference numerals throughout. Further, certain terms of orientation may be used, such as "upper," "lower," "top," "bottom," "left," "right," "inside," "outside," "interior," "exterior," "in ner," and "outer." These terms are generally for convenience of reference, and should be so understood unless a particular embodiment requires otherwise.

Fig. 1 depicts a top view of an exemplary embodiment of an arrangement according to the present invention for forming the inner dimension of a cavity and inserting armor elements. An arrangement 100 comprises a casing 102 having at least one cav ity 103a, 103b (denoted by a dashed line) for a number of armor elements 104, feed ing means 106 for inserting armor elements 104 into the cavity, and at least one form ing device 108 for providing at least one inner dimension of the cavity to a desired dimensional accuracy.

Materials and dimensions of a casing 102 can vary depending on the particular appli cation. In general, the materials of the casing may be metal alloys, such as aluminium, magnesium, titanium and/or steel alloys, as known by one of ordinary skill in the art.

The person skilled in the art will understand that the casing can comprises a number of cavities. Preferably, the cavities are longitudinal and in one embodiment the cavi ties and armor elements are arranged in layers such that the cavities and armor ele ments in each layer is overlapping the cavities and layers in an adjacent layer.

In an embodiment, the both ends of a cavity 102 are open in order to let the forming device out from the cavity.

In an embodiment, the feeding means 106 comprises supporting means 110 for align ing the forming device 108 and/or armor elements 104 from at least two sides with the cavity. In the embodiment depicted in Fig. 1, the supporting means 110 comprises a plane 112 arranged substantially at the same level with the cavity/cavities of the casing 102 in order to direct the forming device 108 and/or armor elements 104 to the cavity, and at least one wall 114 at the side of the plane 112 for preventing the forming device 108 and/or armor elements 104 from falling off from the plane 112. The em bodiment of Fig. 1 comprises walls 114 at the both sides of the plane 112.

In an embodiment, the feeding means 106 further comprises inserting means, such as a pusher 116, for arranging the forming device 108 and/or armor elements 104 into the cavity. In an embodiment, the inserting means are arranged to push the forming device 108 and/or armor elements 104 into the cavity from the plane 112. In another embodiment, the inserting means are arranged to push the casing 102 towards to the forming device 108 and/or armor elements 104 in order to arrange them into the cav ity. Yet, in another embodiment, the inserting means are arranged to push both the forming device 108 and/or armor elements 104 and the plane 112 towards each other.

Yet, in another embodiment, the forming device 108 comprises one or more forming means, such as structures, shapes, blades and/or the combination thereof, arranged for forming the inner dimension of the cavity. Typically, the forming means are ar ranged at outer surface of the forming device 108 and it will appreciated by a person skilled in the art that the forming device can comprise forming means in more than one of its surface.

In an embodiment, the forming device comprises adjustable forming means, such as one or more adjustable blade, for example.

In an embodiment, the arrangement 100 further comprises at least one setting element 118 having at least one dimension differing from armor elements 104 to be assembled for staggering the armor elements 104 in different cavities 103a, 103b. In an embod iment, the width of the setting element 118 is selected to be a half of the width of the armor element 104. Setting elements can be place before, behind and/or both sides of the armor elements.

In an embodiment, the arrangement 100 further comprises holding means (not shown) for keeping the casing 102 stationary.

Yet, in another embodiment, the arrangement 100 further comprises heating means (not shown) for providing at least partial thermal expansion of the casing. 102.

Fig. 2 is a flowchart of an embodiment of a method according to the present invention for forming the inner dimension of a cavity and inserting armor elements.

At method start-up 200, preparatory actions may take place. At step 202, at least one forming device is arranged in the feeding means before armor elements to be assembled.

At step 204, the casing and/or the forming device are/is pushed towards each other for forming at least a part of the cavity to a desired inner dimension before inserting armor elements into the cavity.

In an embodiment, the method further comprises a step of arranging the armor ele ments in the feeding means for inserting them into the cavity.

In an embodiment, the method further comprises a step of arranging a setting element in the feeding means for staggering the armor elements in different cavities.

In an embodiment, the forming device is arranged in front of the armor elements in the feeding means, and the armor elements and additionally one or more setting ele ments are inserted to the cavity at step 204. In another embodiment, steps 202 and 204 are performed before inserting the armor elements and additionally a setting ele ment in the cavity. The person skilled in the art will appreciate that in the latter em bodiment, the steps 202 and 204 can be executed more than once and the forming device may vary.

In an embodiment, the method further comprises a step of fixing the casing to a sta tionary state. This step is preferably performed before executing step 204.

In another embodiment, the method further comprises a step of heating the casing for providing at least partial thermal expansion of the casing. This step is also preferably performed before executing step 204.

At 206, the method execution is ended.

The scope of the invention is determined by the attached claims together with the equivalents thereof. The skilled persons will again appreciate the fact that the explic itly disclosed embodiments were constructed for illustrative purposes only, and the scope will cover further embodiments, embodiment combinations, manufacturing processes, and equivalents that better suit each particular use case of the invention.

Claims

1. An arrangement for manufacturing a ballistic armor comprising: a casing comprising at least one cavity for a number of armor elements, - feeding means for inserting armor elements into said cavity, and at least one forming device for providing at least one inner dimension of said cavity to a desired dimensional accuracy, wherein said forming device is arranged in said feeding means for forming at least a part of said cavity to a desired inner dimension before inserting armor elements into said cavity.

2. An arrangement according to claim 1, wherein said feeding means comprises supporting means for aligning said forming device and/or armor elements from at least two sides with said cavity.

3. An arrangement according to any of preceding claim, wherein said feeding means further comprises inserting means, such as a pusher, for arranging said forming device and/or armor elements into said cavity.

4. An arrangement according to any of preceding claim, wherein said forming de vice comprises one or more forming means, such as structures, shapes, blades and/or the combination thereof, arranged for forming said inner dimension of said cavity.

5. An arrangement according to any of preceding claim, wherein said arrangement further comprises at least one setting element having at least one dimension differing from armor elements to be assembled for staggering the armor elements in different cavities.

6. An arrangement according to any of preceding claim, wherein said arrangement further comprises holding means for keeping said casing stationary.

7. An arrangement according to any of preceding claim, wherein said arrangement further comprises heating means for providing at least partial thermal expansion of said casing.

8. A method for manufacturing a ballistic armor by using an arrangement accord ing to any of claims 1- 7 comprising at least the steps of:

- arranging at least one forming device in said feeding means before armor elements to be assembled;

- pushing said casing and/or said forming device towards each other for forming at least a part of said cavity to a desired inner dimension before inserting armor ele ments into said cavity.

9. A method according to claim 8 further comprising step of arranging the armor elements in said feeding means for inserting them into said cavity.

10. A method according to claim 9 further comprising step of arranging said setting element in said feeding means for staggering the armor elements in different cavities.

11. A method according to any of claims 8-10 further comprising step of fixing said casing to a stationary state.

12. A method according to any of claims 8-10 further comprising step of heating said casing for providing at least partial thermal expansion of said casing.