EP2944914A1

EP2944914A1 - Long-range aerodynamic pellet for airsoft and military training

Info

Publication number: EP2944914A1
Application number: EP14737753.5A
Authority: EP
Inventors: Luis Henrique López-Pozas Lanuza
Original assignee: Bioplast Future Sl
Current assignee: Bioplast Future Sl
Priority date: 2013-01-14
Filing date: 2014-01-13
Publication date: 2015-11-18
Also published as: WO2014108587A1; US20160131462A1; ES2486065A1

Abstract

The invention relates to a variety of pellets for using in the sport Airsoft and for military training, said pellets being novel in that they have a more aerodynamic design based on a surface that reduces the air friction and allows a longer range.

Said pellets are characterized in that they have a surface forming different geometric figures such as a hexagon, pentagon, triangle, circle or square, that create a turbulent flow in the surrounding air layers, thereby obtaining a longer range and improved shooting precision.

Description

OBJECT OF THE INVENTION

The present invention relates to a variety of pellets for use in the sport called "Airsoft" and for military training, with the novelty of having a more aerodynamic design based on a surface that reduces friction with the air and allows a longer range.
This novelty provides to the subject of the invention significant advantages over the prior art. Its industrial application falls within the scope of the preparation of pellets for said "Airsoft" sport and for military training.
The aim of the sport "Airsoft" and of the military training is to practice military simulations safely and without the risk of damaging the opponent that must be shot.
"Airsoft" is based on replicas of firearms. The barrel is smooth and works using a spring, gas or an electric motor. The power of these replica weapons ranges from 0.5 joules to 3 joules, the most common power being 1 joule.
These replicas with smooth barrels shoot spherical and smooth pellets of plastic materials, ranging from 0.12 g to 0.50 g, and having a caliber ranging from 6 mm to 8 mm.
The difference between conventional bullets or projectiles and pellets is based on the fact that bullets or projectiles require a striated barrel that gives a spin or angular momentum to keep them longer in their trajectory. In addition, bullets and projectiles are made of heavy metals to confer them precision and range. On the other hand, they are projected by the high pressure of the gases produced by an explosive charge in the barrel, which provides them with their intrinsic characteristic of being lethal.
The pellets of the present invention are non-lethal, not based on striated barrels, or driven by gas fired by explosives or firearms.
The pellets for "Airsoft" and military training are extremely light, between 0.12 g and 0.50 g, are not lethal, have short-range, are not used with weapons having striated barrels and are shot by a small spring or a low power electric motor.
The range of the pellets currently used in "Airsoft" varies depending on the weight of the pellet and on the power of the replica that shoot them, generally having a range between 20 and 40 meters for pistols and submachine guns, and 60 to 70 meters for sniper rifles, which excessively limits the game strategies, and the pellets loose speed and the trajectory and shooting accuracy varies significantly, the consequence being notably that many misfires occur, increasing consumption and cost, and makes necessary to have short shoot ranges for being accurate. On the other hand, having to shoot at shorter distances in this practice causes inconveniences such as more severe and painful skin abrasions.
Another disadvantage of conventional smooth spherical pellets is the fact that they generate more contact points within the barrel on its way out, so they lose power and range. This is because its smooth spherical shape creates more friction with the barrel, being in permanent contact with the circumference, resulting in loss of output speed, of range and of accuracy in shooting.
The proposed invention solves, among other drawbacks, this short-range of the conventional smooth pellets and greatly improves the range of action of military simulation, achieving greater shooting range and realism in the development of this practice, while reducing the physical damages of practitioners, because the pellets are able to be shot from longer distances.
On the other hand, having longer ranges and better flight path, reduces the number of shots, thus achieving ammunition savings while improving the quality of the practice of this activity, based primarily on stealth participants. Making less shootings does not reveal the situation and therefore provides more realistic and strategy possibilities in military simulations.
The aerodynamic feature of the pellet according to the present invention provides a longer range, between 35 and 55 meters for pistols and submachine guns, and 85 to 95 meters for sniper rifles, representing a gain of more than 40% with respect to the current range. This is a significant improvement and innovation in the practice.
Moreover, by reducing the contact surface within the barrel, because the recesses or concavities not rubbing with the latter, higher output speed is achieved, thereby improving the accuracy and trajectory of the shot.

BACKGROUND OF THE INVENTION

The state of the art in preparing pellets for the "Airsoft" sport has evolved to always provide smooth spherical pellets and has only focused on the development of materials but not on aerodynamics for achieving a longer range.
In this regard, the patent No. ES2373161 relates to bioplastic pellets being 100% biodegradable, the patent application No. US 2007/0240601 A1 relates to a biodegradable pellet, the patent application No. US 2008/0090940 A1 relates to an ammunition soluble in cold water and biodegradable and the method for preparation thereof but no pellet applied to this type of ammunition, like the one proposed by the present invention, is known.
The novelty of this invention lies in the aerodynamic properties. This is a rough or coarse spherical pellet which whole surface is molded with a series of projections forming geometric figures.
Two types of resistance are experienced by a spherical pellet. The first one is due to air friction and represents only a small part of the resistance experienced by the pellet. The main part of resistance comes from the separation of the air flow, which can be laminar or turbulent, and is known as pressure resistance due to the separation.
For a smooth sphere (2) passing through a flow of air, the laminar flow (1) is separated very soon (3), as shown in Figure 1. However, for a rough sphere (4), with a turbulent flow (5), separation is delayed (6), as shown in Figure 2. The separation area in the case of turbulence (6) is much lower than for laminar flow (3).
The greater the separation area of laminar flow, the higher the pressure resistance in the pellet. Because of this, in the development of the present invention, a longer shot was experienced with a pellet having recesses or concavities on its surface. The surface roughness causes the flow to change from laminar to turbulent. Turbulent flow has more energy than the laminar, and therefore the flow remains united over time, creating a forward thrust effect, thus increasing the range of the pellet.
With respect to the shortcomings exposed, the advantages of the present invention are to provide a longer range of shot (40%), a greater accuracy in shooting, a wider range of action for the practice of this activity, saving in consumption of ammunition, and less physical damage as the targets can be shot from a longer distance. Finally, a greater realism of military simulations, for which it is developed, has been achieved.
When developing the invention, varieties of different geometric figures have been experienced, including, without limiting the number of sides of the polygon figures to be formed, squares, triangles, pentagons, rectangles, circles and hexagons, although hexagonal figures resulted in less air resistance than the other shapes.
The production of the pellets can be implemented using thermoplastic injection molds, injection being the most economical manufacturing process to generate higher volumes of pellets.
The ideal materials for manufacturing these pellets are conventional thermoplastic derivatives of petroleum, petroleum biodegradable thermoplastics and biodegradable thermoplastics such as bioplastics of vegetable origin.
The following conventional thermoplastic can be used: (ABS) acrilonitrilobutadienstyrene, (CA) cellulose acetate, (EP) epoxy, (EVA) ethyl vinyl acetate, (HDPE) high density polyethylene (LDPE) low density polyethylene (MF) melamine formaldehyde, (PA) polyamide, (PB) polybutadiene, (PBT) polybutylene terephthalate, (PC) polycarbonate, (PEI) Polyesterimide, (PES) Polyethersulphone, (PET) polyethylene terephthalate, (PF) phenol-formaldelryde, (PMMA) polymethyl methacrylate, (POM) methylene polyethylene oxide, (PP) polypropylene, (PPS) polyphenylene sulfide, (PS) polystyrene, (PTFE) polytetrafluoroetlrylene, (PUR) polyurethane, (PVC) polyvinyl chloride, (SAN) styrene-acrylonitrile, (SB) butadiene styrene, (TPE) thermoplastic elastomer, (TPU) thermoplastic polyurethane, (UHMWPE) ultra-high molecular weight polyethylene, (UF) urea formaldehyde, (UP) polyester, or any other suitable thermoplastic for injection molding. In order to achieve higher pellet weight, the thermoplastics can be charged with various salts such as calcium carbonate, bicarbonate, barium sulfate, or oxide type mineral powder of iron or other heavy metals, in order to increase the relative weight with respect to the volume, to obtain the desired weight. For the latter purpose, it is also possible to make blends of two or more plastics, each in a proportion between 5% to 95%.
To exploit the phenomenon of oxy-degradation or photo-fragmentation, conventional plastics such as polyethylene, polypropylene, polystyrene and PVC etc., a catalyst or a degrading additive is added thereto, that sensitize them such that the ultraviolet radiation from the sun catalyzes their degradation into increasingly smaller fractions.
Among biodegradable thermoplastics derived of petroleum, are compounds of biodegradable polymers and elastomeric polymers such as synthetic rubber, with the addition of a charge of inert and nontoxic mineral from the group of the carbonates and mineral salts, such as calcium carbonate, sodium bicarbonate or barium sulfate, with a maximum of 80% of the mixture. Among biodegradable thermoplastics from non-renewable resources (oil, gas), are polycaprolactone and certain polyesters and aliphatic-aromatic polymers, such as synthetic rubber elastomers.
Among biodegradable thermoplastics from renewable sources, are bioplastic compounds formed by polymers of plant origin such as rubber, latex, cereal and potato starch, and cellulose, with the addition of a charge of inert and non-toxic mineral, from the group of carbonates and minerals salts, such as calcium carbonate, sodium bicarbonate or barium sulphate, with a maximum of 95% of the mixture. This group includes bioplastics based on PLA (polylactic acid), polyester copolymers such as polyhydroxybutyrate (PHB) / polyhydroxyvalerate (PHV); pullulan (a polysaccharide); etc.
Biodegradation property of the variety of the pellets according to the present invention, made of the different types of biodegradable materials mentioned depends mainly on the action of microorganisms and fungi. These microorganisms produce enzymes which catalyze the breakdown of complex materials used as substrates (polymers) into units more susceptible of being assimilated by microorganisms for the production of biomass.
All these processes are regulated and standardized. American Standard ASTM D 6400-2004 "Standardized Specification for Compostable Plastics" and the European standard EN 13432: 2000 "Containers and packaging. Requirements for packaging recoverable through composting and biodegradation". Under normal composting conditions, 90% of the mass is biodegraded into gases, CO₂, methane and O₂, leaving a biomass solid residue of 10%, thus achieving 100% biodegradability and complying with the regulations.
In addition to biodegradation, it is important to mention the bio-disintegration. This occurs in composite materials which are constituted by a biodegradable component and a non-biodegradable component in a proportion between 5% and 95%, such as for instance a mixture of PLA or bioplastics based on starch and PP (polypropylene), a conventional plastic, in a ratio ranging from 5% to 95% of the mixture.
Both oxo-degradable thermoplastics and biodegradable plastics or bioplastics offer an added advantage of no environmental pollution.

DESCRIPTION OF THE INVENTION

The long-range and aerodynamic pellet for Airsoft and military simulation object of the present invention is constituted from a sphere whose surface form recesses or concavities of hexagonal shapes, between 5 and 100 units distributed such that the weight of the pellet remains balanced in both hemispheres. The spherical surface of the pellet is covered, partially or completely, with these recesses, which have a depth between 0.01 mm and 2 mm. (Figure 3).
In a different embodiment, the sphere exhibits recesses with other different shapes than hexagon, such as triangles, squares, pentagons and circles, between 5 and 100 units being distributed such that the weight of the pellet remain balanced in both hemispheres. The spherical surface of the pellet is covered, partially or completely, with these recesses, which have a depth between 0.01 mm and 2 mm. (Fig.6).
In another different embodiment, the sphere exhibits recesses with a combination of two or more geometric shapes, between 5 and 100 units being distributed such that the weight of the pellet remain balanced in both hemispheres.
The spherical surface of the pellet is covered, partially or completely, with these recesses, having a depth between 0.01 mm and 2 mm. (Fig.5).

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the proposed invention, an embodiment thereof is shown in the following drawings, by way of non-limiting example:

Figure 1: Schematic view of the fluid layers and the friction in the case of a smooth pellet.
Figure 2: Schematic view of the fluid layers and the friction in the case of a rough or coarse pellet.
Figure 3: conventional perspective view of the aerodynamic pellet.
Figure 4: View of a section of a pellet.
Figure 5: conventional perspective view of the aerodynamic pellet with hexagonal and pentagonal recesses.
Figure 6: conventional perspective view of the aerodynamic pellet with triangular recesses.

The reference numerals in these figures correspond to the following:

(1) Laminar air flow
(2) Conventional spherical smooth pellet
(3) Laminar flow separation arch for the smooth spherical pellet.
(4) Aerodynamic rough pellet.
(5) Turbulent air flow
(6) Turbulent flow separation arch for an aerodynamic rough pellet.
(7) Sphere of the pellet.
(8) Surface area of the sphere of the pellet.
(9) Hexagonal-shaped recess.
(10) Hemispheres of the aerodynamic pellet.
(11) Depth of the recess with respect to the surface of the pellet.
(12) Pentagonal-shaped recess.
(13) Hexagonal-shaped recess.
(14) Triangular shaped recess.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION.

A preferred embodiment of the present invention is constituted from a sphere (7) whose surface (8) exhibits hexagonal-shaped recesses (9), 100 units thereof being distributed such that the weight of the pellet remain balanced in both hemispheres (10), and with a depth of 0.5 mm with respect to the surface of the sphere (11).

Claims

Long-range aerodynamic pellet for the sport called "Airsoft" and for military training, having a spherical surface, characterized by having hexagonal recesses.
Long-range aerodynamic pellet for the sport called "Airsoft" and for military training characterized in that, in different embodiments, the spherical surface exhibits recesses having geometric shapes being different from the hexagon shape.
Long-range aerodynamic pellet for the sport called "Airsoft" and for military training, characterized in that, in different embodiments, the spherical surface exhibits a composition of recesses having two or more combined geometric shapes.
Long-range aerodynamic pellet for the sport called "Airsoft" and for military training according to claims 1-3, characterized in that the number of geometric-shaped recesses for partially or completely covering the surface ranges from 6 to 100 units.
Long-range aerodynamic pellet for the sport called "Airsoft" and for military training according to claims 1 to 4, characterized in that the geometric-shaped recesses have a depth ranging between 0.01 mm and 2 mm as from the surface.
Long-range aerodynamic pellet for the sport called "Airsoft" and for military training according to claims 1-5, characterized in that, for the manufacturing thereof, a conventional thermoplastic material of petroleum origin is used, with the addition of a charge of mineral or metal salts in a maximum of 80% of the mixture.
Long-range aerodynamic pellet for the sport called "Airsoft" and for military training according to claims 1 to 5, characterized in that, for the manufacturing thereof, a thermoplastic oxo-degradable material of petroleum origin is used, such as PVC, polyethylene, polypropylene, polystyrene or other suitable plastic, with the addition of a catalyst.
Long-range aerodynamic pellet for the sport called "Airsoft" and for military training according to claims 1-5 characterized in that, for the manufacturing thereof, a biodegradable thermoplastic material of petroleum origin is used, such as polycaprolactone, aliphatic polyesters with the addition of a charge of inert and non-toxic mineral such as calcium carbonate, sodium carbonate or barium sulfate, with a maximum of 80% of the mixture.
Long-range aerodynamic pellet for the sport called "Airsoft" and for military training according to claims 1 to 5, characterized in that, for the manufacturing thereof, a biodegradable thermoplastic material of plant origin is used, such as rubber, latex, cereal and potato starch, or celluloses, or bioplastics, such as polylactic acid, with the addition of a charge of inert and nontoxic mineral, such as calcium carbonate, sodium carbonate or barium sulfate, with a maximum of 80% of the mixture.