JPH0413637B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical field to which the invention pertains) The present invention relates to a marine flare that is dropped from an aircraft and used for marking a position on the sea.

(Prior art) Conventionally used marine flare canisters have a paper cylinder filled with a powdered material whose main component is red phosphorus, which is a flame extinguishing agent, in a metal cylinder, and the igniter and igniter are fired. It is used to ignite a seawater battery, and the combustion products of red phosphorus emit flame and smoke to mark the location at sea. Its configuration is shown in FIG. In the figure, 1 is an impact plate, 2 is a warhead hardware, 3 is a cylinder, 4 is a battery storage tube, 5 is a flame tube, 5-1 is a charge, 5-2
5-3 is a paper cylinder, 5-3 is an igniter, 6 is a flame tube, 7 is a tail, and 7-1 is a flame hole plug.

(Disadvantages of conventional devices) Conventional marine flares have the above structure, and when dropped from an aircraft onto the sea, they operate normally at the conventional dropping altitude of about 600 meters and are effectively used to mark maritime positions. However, with the advancement of maritime weapon systems, it became necessary for aircraft to increase the drop height by more than an order of magnitude, but conventional flares could not withstand this increase in altitude, and were deformed and damaged by the impact of falling. However, it had the disadvantage of interfering with normal operation. In addition, conventional marine flares are greatly affected by the wave conditions at the sea surface at which they are dropped, and under weather conditions of wave class 3 or higher, they are submerged in water, blocking the flare action and significantly reducing the marking effect. . In addition, conventional models had a drawback that the waiting time for ignition after landing on the sea surface after being dropped was extremely long, ranging from 20 seconds to 46 seconds, and the variation in time was ±13 seconds. Furthermore, there was a problem in that there was no mechanism for natural submersion after the flaming action ended. In addition,
If a flare at sea that fails to explode is not scuttled, it could drift forever at sea and become the source of an unexpected accident, and the lack of a scuttling function was a major drawback. In other words, it was something that could be called unfinished for this kind of equipment.

(Objective of the Invention) This invention eliminates the above-mentioned drawbacks, and provides impact resistance, wave resistance, and resistance to drop from a required altitude.
This was done for the purpose of imparting short-time effectiveness and trace-eliminating properties, etc., and is intended to provide a high-performance marine flare that meets the required performance.

(Structure of the Invention) The main point of the present invention is to improve or newly add four completely independent performances to a conventional marine flare tube, and to achieve this while keeping the external shape and dimensions as small as possible. In other words, improvements in impact resistance as the drop height increases, measures to prevent flooding in rough seas with wave class 3 or higher, shortening and stabilizing the time it takes for flames to start after landing, and scuttling after use. This is the simultaneous achievement of four goals: adding functionality. The above four goals are independent functions, but the structure of the conventional flare tube must be modified to incorporate all of these previously unseen performances. However, since there are only very limited opportunities to repeat experiments by dropping actual objects under such conditions, we must make effective use of past experience, theory, and insight. There was no other choice but to try to obtain the desired results through experiments.

The following is the technical idea that was followed to arrive at the configuration of this invention.

A flare dropped from an aircraft falls onto the sea surface with its tail facing up, in the same position as a regular bomb. Previously, the drop height was around 600 meters, but in the future it will reach over 1,650 meters, and the acceleration upon landing will be several thousand grams. In this case, the angle of incidence is approximately a right angle, and the impact plate and cylinder body receive the most axial force. Shock plates have conventionally been made flat in order to prevent them from sinking deeply due to the impact they receive, but the center of the flat surface is recessed inward. If the gap between the recessed tip and the battery housing tube is too narrow, there is a risk of contact and damage to the seawater battery inside. In order to connect and fix the cylinder to the warhead metal fittings, there are eight holes around the adhesive part for passing countersunk screws, and buckling occurs due to compressive stress when landing on water, causing local destruction around the holes. The seawater that seeps in from there prevents combustion and causes the fire to go out midway through. Therefore, in this invention, in order to avoid deformation and damage of the impact plate and the cylinder, the shape of the impact plate is changed from a flat structure to a spherical curved surface, and a porous synthetic resin buffer plate is attached to the surface of the impact plate. I did this. This area has an extremely effective shock absorbing effect when landing on water, making it possible to withstand increased drop heights. In addition, in order to connect and fix the cylinder and the warhead hardware, the adhesive part is double-sealed around the entire circumference, making it possible to secure a tight and strong fixation. Since there are no openings, there is no risk of breakage, it can withstand drops from high altitudes, and the problem of improving impact resistance has been solved.

Next, consider measures to prevent flooding. A marine flare is constructed by connecting a long and thin metal cylinder, an impact plate at the tip, and a tail section at the rear end. When it floats on water after being dropped, it stands upright with its tail facing upwards. Here, the part exposed above the water is called the floating part, and the part hidden underwater is called the strait part. Conventional marine flares have few floating parts, so in relatively calm seas with wave class 1 to 2, the floating part is called the floating part. There is no risk of flooding, but at sea levels where waves are somewhat high, i.e. wave class 3 or higher, the natural period of the vertical motion of the sea flare will be synchronized with or close to the wave period at that time, and the wave surface will change. This increases the relative displacement of the sea, making it easy for marine flares to be submerged in the waves. If the flame is submerged in water, the flame generation is interrupted, and even if the flame is exposed later on, the amount of flame decreases and the marking effect is significantly inhibited.

By the way, in wave class 3, the wave height is 0.5 to 1.25 meters, the wavelength is 5 to 1.25 meters, and the wave period is
It is 1.8 to 2.8 seconds. On the other hand, the marine flare of this invention has a natural period of vertical motion of about 1.5 seconds (the actual one is 1.48 seconds), so the phenomenon of resonance with waves does not occur, the relative displacement is reduced, and it is no longer submerged in water. . In addition, as the wave class progresses, for example, in 5, the wave height is 2.5 to 4 meters, the wavelength is 25 to 40 meters,
The wave period is 4 to 5 seconds, and the wave height is much higher.
Although the period of the waves increases, the relative motion with the wave front becomes even smaller, so there is no need to worry about flooding.

In order to prevent a marine flare from being submerged in water as described above, it is necessary to increase the length of the cylinder and ensure as large a floating section as possible. To this end, it has been experimentally determined that the optimal length of the floating section is approximately 30% of the total length of the flare tube. Incidentally, the vertical natural period of the conventional marine flare is 2.14
The period of waves on the sea surface with wave class 3 or higher is experimentally known to be 1.8 to 2.8 seconds, which is approximately equal to this, so a design was required to shorten the natural period of vertical motion compared to the wave period. It turns out. If the vertical motion natural period is To, the calculation formula is as follows.

Here, from equation (i), to reduce To, it is sufficient to increase AW, but since there are restrictions on the outer diameter of the cylinder from the point of view of use, the outer diameters of the stuttering part and the floating part should be the same size. I have no choice but to. At this time, the volume of the drainage part V
If the length of the stuttering part is d, then V=AW・d, so equation (i) is becomes. From this equation (ii), it can be seen that in order to reduce the vertical motion natural period To, the length d of the stuttering portion should be reduced. This invention was designed with this point in mind.

Next, as combustion progresses, the overall mass of the flare decreases, the floating part gradually increases, and eventually it tilts.Finally, when the center of buoyancy falls below the center of gravity, it falls sideways, loses its resilience, and tilts. Float in the same position. In this state, the water line area further increases and the vertical motion natural period becomes even smaller, which is a much smaller value compared to the wave period, so the oscillation becomes smaller.

Next, consider the issue of shortening the firing time. The conventional model lowers the center of gravity (32% of the total length) and has a large swamp area, and has good static stability due to small horizontal vibration, so seawater flowing into the battery compartment is prevented from entering the electrode surface of the seawater battery. However, because it took time to reach the amount of water necessary to generate a specified electromotive force, it took a waiting time of 20 to 46 seconds for the marine flare to land on the water and ignite, and this time also varied. There were flaws.
In this invention, the total length of the cylindrical body was increased to raise the center of gravity (35% of the total length), the stuttering part was decreased to increase the rolling motion, and the diameter of the seawater inlet hole was increased to increase the area of the hole. Since the amount of water required to flow into the battery chamber was expanded, the required amount of water flowing into the battery chamber could be obtained easily and quickly, so the waiting time for ignition was shortened to 7 to 11 seconds, became stable, and had fewer variations.

Furthermore, consideration will be given to adding a scuttling function.

It is extremely undesirable for marine flares that have finished their combustion and are no longer used, or those that have failed to explode or become defective due to breakage, to continue floating and drifting on the sea surface forever. Therefore,
It became necessary to install a scuttling device, which was not included in conventional products.

This scuttling device consists of a scuttling cylinder and a water-soluble substance (sugar, baking soda, dextrin, etc.) pressurized into the scuttling cylinder, and is attached to an appropriate position on the cylinder. While floating, it is constantly exposed to seawater even if it is tipped on its side, so it is corrected with a weight attached to the cylinder so that it always points below the water's surface. Throughout the year, on the sea surface in environments with different surrounding conditions, even if there is a difference in the dissolution rate of the scuttling drug, it will be dissolved or eroded by the seawater within 7 hours, and the seawater will enter the cylinder and submerge it, so it will continue to float. The danger is gone.

(Embodiment of the present invention) Next, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 2 is a longitudinal sectional view of one embodiment of the present invention. In the product of this invention, the same parts as those of the conventional product shown in FIG. 1 are given the same reference numerals, and corresponding parts, although not completely the same, are shown with the same reference numerals and the suffix "a". That is, in the figure, 1 and 1a are impact plates. The material used is forged steel, which is strong and heavy, and is strong enough to prevent shearing even when subjected to a large vertical load, and serves as a weight to keep it vertical when floating on the sea surface. There are four holes on the side to allow seawater to flow into the battery chamber.

1 in Fig. 1 is a plane with a bottom thickness of 4.5 mm, and the diameter of the seawater inlet hole is 10 mm.The distance between the bottom and the battery housing cylinder is as short as 4 mm, and there is a possibility that they will come into contact if the bottom is dented. On the other hand, 1a in Fig. 2 has a bottom thickness of 6 mm and a part of a 260R spherical surface.
It is made strong enough to withstand drops.
The diameter of the seawater inlet hole was 12 mmφ, and the distance from the battery housing cylinder was 20 mm, eliminating the possibility of connection. 1a-1 is a non-conventional cushioning material made of a thin plate made of porous synthetic resin, and although it is not very strong, it has a sufficient cushioning effect to absorb impact.
In the example, as a result of a drop test from a height of 12 meters, there is a difference in the acceleration that the shock plate receives when the shock plate is attached and when it is not attached. In other words, the weight of 6,600g without the buffer plate decreased to 3,900g with the buffer plate attached, clearly confirming that it has an absorption effect.

In the figure, 2 and 2a are warhead hardware. The material is aluminum, and the shock plate 1 and the simplified body 3 are glued and fixed on the sides. A battery storage tube 4 is attached to the bottom surface, and flame tubes 5, 5a are attached to the top surface. In the figure, 3 and 3a indicate a cylindrical body. The material of the cylinder is aluminum, and the actual cylinder is a long cylinder with an outer diameter of 120 mm and a thickness of 2 mm. The length of conventional product 3 is 520 mm, the outer diameter of the water line is 84 mm, and the water line area is 5540 ^mm2 . The warhead metal fittings are fixed with eight screws, and screw holes are drilled into the cylinder body.This part is weak in strength, and when it lands on water, a compressive load is applied, causing damage around the screw holes. This caused seawater to often infiltrate.
The cylindrical body 3a has a long length and a large water line area AW to prevent flooding. The length is 630mm, the outer diameter of the waterline part is 120mm, and the waterline area is 1130mm ^2. The warhead hardware is bonded to the warhead hardware by double seaming around the entire circumference with a 3mm deep groove, allowing for a tight and strong adhesive fixation. 3a-1 is a scuttling device, which is installed at a position 380mm from the bottom of the impact plate. The scuttling device consists of a scuttling tube and a scuttling agent, and 0.5 grams of a mixture of baking soda and dextrin is pressurized into a tube with an outer diameter of 10 mm and a length of 15 mm. 4 in the diagram
indicates the battery storage cylinder. This is an aluminum melter that houses one seawater battery.The battery is made by swirling special electrode plates (silver chloride with silver foil on the anode and magnesium on the cathode) and injecting seawater. A primary battery that works as a power source to ignite the ignition ball. The performance is when seawater is injected.
With a resistance of 1 ohm, a current of 0.9 amperes or more flows within 3 seconds. In the figure, 5 and 5a indicate flame tubes.
The drugs 5-1 and 5a-1 are contained in the tube.
The charge is pressurized into the paper cylinders 5-2 and 5a-2, the upper layer is filled with ignition powder, and the ignition balls 5-3 are double mounted. The materials commonly used for this type of flare are well known. The main ingredient of the flaming agent is red phosphorus, along with manganese dioxide as an oxidizing agent, magnesium as a combustible agent, and a heating agent.
A small amount of vegetable oil is added as a binder to the metal powders of aluminum and silicon iron and the mixture of these powders to facilitate filling and control combustion. When burned, it emits a bright yellow-white flame and white smoke. Although there is not much difference between the conventional product and the present invention in terms of the composition of the drug, there are considerable changes in drug size, drug length, and drug amount. 5a-4 is a buffer seat, and a 2 mm thick buffer rubber plate is interposed at the joint between the flame tube and the warhead hardware.

In the figure, 6 and 6a indicate a flare tube. It is a wooden tube that connects the flame tube and the blast hole, and the hollow part serves as a passage for gas. In the figure, 7 indicates the tail. There is no difference between the conventional product and this invented product. It consists of four vertical wings made of aluminum, which are glued and fixed to the cylinder body with six screws. Reference numeral 7-1 is a smoke hole plug which is released and opened by combustion gas pressure.

(Effects of the Invention) According to the present invention, it can withstand being dropped from high altitudes, where conventional marine flares were damaged and could not be used, and in rough sea conditions of wave class 3 or higher, where conventional products could not be used effectively. However, it is possible to obtain a marine flare that can be used effectively continuously, and the waiting time until it starts operating as a flare after landing on water can be significantly shortened. By installing a scuttling device, items that have drifted and become unsafe can be sunk safely and reliably into the sea, which is highly effective for special purposes.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of a conventional marine flare, and FIG. 2 is a vertical cross-sectional view of an embodiment of the present invention. In the figure, 1...impact plate (conventional), 1a...impact plate (this invention), 1a-1...buffer plate, 2, 2a...warhead hardware,
3, 3a... Cylindrical body, 3a-1... Scuttling device, 4... Battery storage cylinder, 5, 5a... Flame charge tube, 5-1, 5a-1...
drug, 5-2, 5a-2... paper tube, 5-3... ignition ball, 5a-4 buffer seat, 6, 6a... squirt tube, 7... tail, 7-1... blowhole plug. .

Claims (1)

[Claims] 1. A flame tube filled with chemicals is built in the center part, and a seawater battery is built in the lower part, which is the power source for igniting the igniter and is activated by the injection of seawater from the seawater inflow hole, and a gas passage is built in. A cylindrical body with a built-in blast tube built into the upper part and a flame nozzle plug attached to the upper end, a tail fin located outside the upper part of the cylindrical body, and a shock absorber installed at the bottom of the cylindrical body. In the marine flare tube equipped with a plate, the impact plate that is directly hit by seawater has a curved surface, and a buffer plate made of porous synthetic resin is added to the outer surface of the impact plate, and about 30% of the total length of the cylinder body is a floating part. By doing so, we set the vertical motion natural period to approximately 1.5 seconds, and also increased the overall length of the cylinder to raise the center of gravity, reduce the stuttering area, increase the horizontal oscillation, and widen the seawater inlet hole. 1. A marine flare comprising: a scuttling tube in which the outer wall of the cylindrical body serves as an opening; and a scuttling device made of a water-soluble substance pressurized into the scuttling tube.