Method of and apparatus for the storage of equipments, machines, and vehicles under controlled atmosphere The present invention relates to the storage of equipments containing iron parts which are susceptible of oxidation and, more particularly, a method and an apparatus for storing military means such as aircrafts, helicopters, tanks and/or parts thereof under a controlled atmosphere of inert gas so that both oxidation and accumulation of atmospheric dust as well as settlement of animals and development of plants are avoided. At the same time such military vehicles are kept hidden by camouflage textile envelopes to sensor means which operates for finding and locating them in the bands of the electromagnetic spectrum of the visible field (VIS), thermal infrared (TIR), radar operating at 3 to 140 GHz and ultraviolet rays UV.

It is known that an important problem is to keep materials efficient, especially those of strategic importance that are stored awaiting hypothetical use.

Vehicles of considerable dimensions such as aircrafts or tanks do not find ever place under cover in hangars or stores. In most cases they are left outdoors on the ground or paved yards. Although such materials are stored in areas where the weather guarantees dry air and no rain, such as deserts, it is unquestionable that both oxidation and accumulation of dusts are significant troubles. Additionally, there is a not

negligible danger of the settlement of animals and development of weeds.

The present invention seeks to solve the above problems by enclosing the single vehicle to be stored into a sealed textile envelope, blowing an inert gas under a light overpressure into such envelope, and keeping the pressure under control in order to restore the initial pressure automatically if a predetermined critical thr-esrluld is exceeded.

Another object of the invention is to camouflage the single vehicle to be stored so that it cannot be easily found out by reconnaissance systems provided with sensors operating in the electromagnetic spectrum.

These objects are accomplished according to the invention by using a camouflage textile envelope for each vehicle which is airtight closed by heat seal between the sheets and the two cloth ends of the opening that is necessary for the assembling.

The fabric is preferably of polyester or polyamide fibre or the like which is coated by spreading PVC or another thermoplastic resin, natural and/or synthetic rubber onto both faces of the fabric with or without fabric reinforcement. The camouflage features of the fabric, in addition to the colour composition of the external face thereof, are obtained by adding suitable fillers capable of opposing the action of the sensors operating all over the electromagnetic spectrum during the spreading of PVC.

The closure of the opening which is necessary for bringing the armaments or parts thereof or other vehicles to be stored into the envelope is carried out by heat seal and/or mechanical gastight systems.

The description will be more readily understood with reference to the annexed sheets of drawing which show only by way of a not limiting example a preferred embodiment of the invention. In the drawings: Fig. 1 is a diagram of an apparatus according to the invention; Fig. 2 shows a perspective view of a closed envelope according to the invention; Fig. 3 shows a detail of the input valve for the inert gas; Fig. 4 shows a detail of the air intake valve; Fig. 5 shows the use of elastic ropes to keep the pressurized envelope close to the stored means.

With reference to the figures an apparatus according to the invention includes a plurality of textile envelopes C with dimensions suitable for the armaments and/or parts thereof to be stored inside them. Such envelopes C are made by means of suitable templates shaped according to a prototype of the armament to be

stored.

Advantageously, in case of military use the fabrics used for the envelopes to be placed outdoors will have typically military features. Particularly the external side of the fabric under the form of a sheet and/or foil can show a"dull"surface with uniform or camouflaged colour or with several colours similar to those of the surrounding land with low brightness factor such as to have a gloss < Fabrics Fabrics military features and forming the envelopes will be provided with concealing characteristics for opposing the reconnaissance sensors operating at the wavelenghts of the electromagnetic spectrum during the production step by adding and/or putting between the carrying textiles necessary for giving mechanical resistance to the envelope and the spread PVC, or within the PVC itself, suitable fillers such as to provide the multispectrum camouflage features required by the army such as VIS, NIR, TIR, RADAR for loam or deserts, and UV for snowy lands, or by providing covers outside the envelopes.

Of course, the envelopes can also be made by fabrics and/or foils and/or sheets without any military features so that they can have different colours irrespective of the fabric surface gloss.

Each envelope C is provided with at least a valve D for the air intake, a valve V for the inert gas intake, a valve K for the actuation of control apparatus, and an inert gas electrovalve Z for adjusting the pressure in the envelope during the

operation. As can be seen from Fig. 1, a feeder A of inert gas can be connected to a plurality of envelopes C at their input valves V through a pipeline T.

According to a peculiar feature of the invention the sealed envelopes C are micropressurized by inert gases, nitrogen being prevailing. Such a pressurization within the cover aims at avoiding that, in case of differential pressure with respect to the atmosphere equal to zero or a negative pressure value, the thegasmixtureinsidethecoverof tends to restore the gas composition of the atmosphere because of the gradient concentration force. In this way, a percent amount of oxygen greater than 0.2% is prevented from being naturally restored within the envelopes, such an amount being, as known, the absolutely safe quantity capable of preventing oxidation processes on the surface of the stored means from being started and/or those oxidation processes already in progress before the storage from being continued.

Therefore, the micropressurization will prevent any change in the composition of the inert gas brought into the cover, thus preventing also the plastic materials of the stored means from becoming weak.

In order to avoid oscillations of the pressurized cover under the force of the wind, the fabric is kept tight to the stored means by several elastic ropes E so as to form several small bulges or swellings in the cover between adjacent ropes because of the pressurization.

The final conditions of a sealed, pressurized cover containing the stored means are reached through a plurality of air intake cycles for expelling the air contained in each small bulge of the cover as well as a plurality of inert gas inlet cycles until the oxygen contents in the gas mixture within the cover is lower than or equal to 0.2%.

In operation, the micropressurization is automatically kept within the regulation limits by a differential <BR> <BR> <BR> <BR> pressure switch P connected to each e1lvelope C al-d able to control the opening of each valve V located in the inert gas supply circuit of the cover or the several cover bulges or swellings located side by side without any direct connection to one another, as the micropressurization decreases. Once the maximum predetermined value of micropressurization is restored, valve V closes automatically.

The inert gas is fed by a gas generator A and/or a set of cylinders and/or a liquid nitrogen tank. Each such system is provided with an automatically operated aid unit which is able to meet the inert gas delivery for a determined time in case of failure of the main gas generator unit or when the set of cylinders or the liquid nitrogen tank are empty. At the same time, an acoustic warning signal actuates the aid unit. Each such gas feeding system can supply several covers placed side by side with inert gas.

A continuous check of the system operation is carried out by a remote measurement system for measuring the percent content of oxygen both within the cover and in

the feeding circuit. In addition, a continuous check of the operation of the gas production unit is carried out by sensors S connected to a processor that will supply the aid unit with a warning signal through a dedicated telephone line in case of any failure in the system operation even in case of vandal acts on the cover, the decrease of the predetermined operating micropressurization being also sensed.

Failing a remote measurement system, the check of the pressurization of each single cover can be carried out by providing an adjustable, calibrated clock in each envelope for measuring the opening time of each pressurization restoring electrovalve in the gas feeding circuit. As the exceeding of the predetermined opening time of the electrovalve is detected through a step relay by such a clock, the latter will actuate both a light signal and an acoustic signal both on site and at a remote distance for signalling the failure and actuating the aid unit.

Furthermore, each envelope is provided with a quantity of hygroscopic salts for removing traces of humidity from the stored means since it is not possible to remove humidity before the storage of such means.