GB2409167A

GB2409167A - Antiviral refrigeration unit for protective suit

Info

Publication number: GB2409167A
Application number: GB0329464A
Authority: GB
Inventors: Edward David Furs
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-12-19
Filing date: 2003-12-19
Publication date: 2005-06-22
Anticipated expiration: 2023-12-19
Also published as: GB0329464D0; GB2409167B

Abstract

A refrigeration unit that may be operated by liquid gas, in combination with ambient gas or air, which sets in motion a useful circulation of air within an enclosed volume. The air may be filtered and the temperature being lowered to a temperature so that viruses and bacteria are inactivated, the gas may then be warmed to a temperature, for example, which is suitable for breathing. The cooling may be carried out using cooling tubes by direct or indirect cooling from a low temperature source which may be liquid air or other gas. The air may be warmed by passing through warming tubes the source of warmth may be ambient air. The flow of the gas/air is produced by gravity as the density variations of the gas/air within tubes due to the variations in temperature result in useful circulation. The enclosed volume may be a protective suit or hood.

Description

24091 67 1.

REFRIGERATION UNITS

This patent application for a refrigeration unit is complementary to other applications, including an application for an environment protection envelope, which will be refrigerated by the refrigeration unit.

The environment protection envelope invention and the refrigeration unit invention are provided for wear by military personnel in combat conditions, for protection from great seasonal heat in oriental countries, and for protection from bacteria and viruses, in addition to the protection provided within the envelope by a chemical filter; and for the protection of populations from epidemics and terrorism. The refrigeration unit is also provided for wear with a light cape or hood, and for wear with a face mask, being a face gas-mask, so that various kinds of work may be undertaken in alert conditions, including office and administration world, while wearers this light protective clothing, and so that ordinary daily tasks and activities may be carried out.

The refrigeration unit is designed to operate from a supply of liquid gas, which may be liquid air, and this unit may be applied by various industries as a convenient and economic cooling means, an example of which might be the production of domestic refrigerators. This description mainly presents an application of the invention to permit the functioning of the environment protection envelope in warfare conditions, and the wearing of light protective refrigerated clothing for daily activities in conditions of great heat, and when a biological or a chemical alert is possible The main functions of this application of the refrigeration unit, are to draw ambient seasonal air into the protection envelope, which air may be at a temperature of +60 Centigrade, to provide a working temperature of about +20 C. When the ambient air is at a lower temperature such as +15 (, a working temperature of +10 C. may be provided. This air is sterilized by cooHng to a temperature of about minus 20 C, thereby partly inactivating bacteria and viruses such as anthrax, ebola and Bars. This sterilized air is then warmed to a temperature of about +20 C, or to a temperature as near as possible to this convenient temperature, for convenient breathing and working.

A circulation of air within the suit is produced by air cooling by the refrigeration unit, and the circulation is completed by the expulsion of used air after further cooling, the expulsion helping to draw in further quantities of fresh air.

One of the aims of this conception has been to provide a refrigeration unit that can usually operate without the application of a mechanical or electrical pumping device for the circulation of the air or the liquid gas. Mechanical or electrical pumps as well as fresh air or oxygen cylinders may however be necessary when a particular type of protection suit is used for fire fighting or for other special purposes, when the ambient air temperature may be about one hundred degrees centigrade.

When a mechanical or electrical pump is not provided, the air circulation is produced by a falling action of the air, under the effect of gravity, after the density of quantities of air has been relatively increased by cooling, thus increasing its 3.

relative weight, and causing the fall. As the air falls through tubes, it draws further quantities of uncooled air into the tube circulation system. The expulsion of used air is also produced by air cooling.

In one presentation of these inventions, it is envisaged that the refrigeration unit may be carried inside the protection envelope, on the chest or on the wearer's back, like a haversack or backpack. It must therefore be of a convenient carrying size and weight. The working of the refrigeration unit will depend on the complementarily of several parameters. One consideration is that the breathing requirement of a fairly inactive person is about seven litres of air per minute, and that of a highly active person may be about fifteen litres per minute.

It is conjectured that the area of the air intake aperture into the protection envelope may be of a dimension in relation to the speed of the natural movement of air in still conditions, so that the air may permeate or diffuse naturally into the protection envelope in sufficient volume to meet the easy breathing requirement of a soldier undergoing heavy exertion such as running with full equipment.

It is estimated that the natural movement of air due to thermal exchange impulses and effects such as Brownien movement may be about eight centimetres per second, and this speed will no doubt be increased by 25% by the lower density of cooled falling air within the tube circulation system, so the natural speed of air entry into the suit may be about ten centimetres per second. If this estimation is incorrect it will have to be corrected. 4.

If the area of the air intake is one hundred square centimetres, formed for instance by sides of 5x20 centimetres, one litre of air will freely enter the suit within a period of one second, or sixty litres per minute, at a speed of ten centimetres per second.

The air intake may be covered by a part of a large three sided or four sided chemical filter, perhaps having side surface area dimensions of 30x5 centimetres or more, or more than 450 square centimetres, into the volume of which may freely pass more than four litres of air per second. The volume of the filter Will contain chemical material for filtering gas and viruses, and the volume may also contain an air drying chemical, perhaps in the form of an exchangeable cartridge, to help to prevent airborne humidity from freezing inside the cooling system.

The refrigeration unit is expected to function by a heat exchange between a supplied quantity of liquid air, and quantities of ambient air which are drawn into contact with a number of tubes, in a box, that are in indirect contact with the liquid air recipient, which tubes of this tube box may be arranged by a limited conduct of cold through metal, and by insulation, to have a temperature of about minus 40 Centigrade. The ambient air will pass through these tubes and thus be cooled.

The tube box may take the form of a box of suitable material, such as a metal, which may be aluminium, which may be mainly constructed by casting or by the assembling of parts. The tube box may mainly consist of a number of tubes, which may be placed horizontally or vertically, within a number of compartments.

In this description the tube box and its operation are described with the tubes in a vertical position.

The tube box may be formed by joining or clipping together two panels of about equal dimensions, that have placed between them a suitable sheet of insulation material, one panel being mainly for cooling air and the other for warming air.

Ambient air will be drawn into the top end of some of the tubes in the tube box, and the temperature of this air will be lowered as the air passes through the tubing under the effect of gravity, since the tubes will be in indirect contact w'th a quantity of liquid air at a temperature of about minus 190 Centigrade, and this contact will suitably lower the temperature of the tubes and the temperature of the enclosed air, which will become relatively heavy.

One consideration is the temperature to which the drawn ambient seasonal air must be lowered for its sterilization or for the inactivation of bacteria and viruses. This sterilization temperature should no doubt be at least minus 20 Centigrade. It is conjectured that if this temperature of -20 C. is maintained for five or six seconds, it might inactivate bacteria and viruses for about two hours, which is a maximum air circulation time within the suit.

Another consideration is the time necessary for the required degrees of heat to transfer from the low temperature tubing to the drawn-in ambient air.

It is estimated that if most or a part of the length of a metal tube of internal diameter of about nine millimetres and an external diameter of about one centimetre remains in suitable indirect contact with a quantity of liquid air, with the ends of the vertically positioned tube open to a circulation of air, the air within the 6.

tube Will cool at a rate of about one degree per one tenth of a second. This estimation must be verified and perhaps corrected. If this rate of cooling estimation is correct, a quantity of cooling air passing down the tube at a speed of ten centimetres per second, will have its temperature diminished by ten degrees centigrade in one second.

According to these considerations, in order to reduce the temperature of about twenty cubic centimetres of incoming air by twenty degrees centigrade in about two seconds, a length of tubing of length twenty centimetres will be required. The lengths of the tubes in the tube box may therefore be varied in order to obtain required temperatures.

The required rate of air entry is fifteen litres per minute, so to pass this required quantity of air per minute through a number of these tubes of diameter of about one centimetre, the required number of tubes will be about twenty five, and their ends will take up an area of about five square centimetres.

The next considerations are the maximum temperatures and the different lower temperatures of the seasonal ambient air, in which the refrigeration units will be designed to operate, and the required temperature to which these ambient air temperatures must be lowered for convenient breathing and working It seems that usual high temperatures in countries such as Iraq may reach +60 Centigrade. It seems probable that low night temperatures may be around minus 10 Centigrade. 7.

It is considered that the convenient breathing and working temperature is about +20 Centigrade.

Therefore, if several groups of about twenty We tube-box cooling tubes are mostly about twenty centimetres long, this length thus reducing the temperature of incoming air by twenty degrees centigrade, the temperature of the incoming air will be reduced by forty degrees if this incoming air is passed through a second group of twenty centimetre long tubes, by sixty degrees by passing the air through a third 9fOUp of tubes, and by eighty degrees by passing the air through a fourth group of tubes.

Therefore, if the refrigeration unit is operating in an ambient air temperature of +60 Centigrade, ambient air that passes through four groups of cooling tubes will have its temperature reduced to minus 20 Centigrade. It is supposed that a temperature of ---20 C. will inactivate viruses such as anthrax, ears and ebola, but if necessary a fifth and a sixth group of cooling tubes may possibly be provided, to produce lower temperatures, but while causing design problems.

The sterilized air will have to be warmed for breathing and working, and this may be done by providing an air warming compartment in the tube-box, next to the air cooling compartment. If for instance the refrigeration unit is operating in an ambient air temperature of +60 Centigrade, quantities of this ambient air may be drawn through the warming compartment of the tube-box, by the cooling of this ambient air in the warming compartment, it being in contact with tubes containing air at minus 20 Centigrade. There will be an exchange of heat between the tubes with air at minus 20 C. which run through the warming compartment and the air at +60 C. in the warming compartment. It is supposed that this exchange of heat 8.

would be at the previously mentioned rate of heat exchange of ten degreesper second and would result in the temperature of the sterilized air rising to zero degree after passing through a first group of tubes twenty centimetres long, and to +20 C. after passing through a second group of tubes, which is the temperature required for convenient breathing and working.

The circulation of this ambient air used for warming cooled filtered air may be established by allowing the cooled ambient air to sink to an air outlet, because of its lowered temperature, relative to its initial temperature. This sinking in turn draws in and through the warming compartment further quantities of ambient air for warming cleaned air.

According to this configuration of parameters, the lowest convenient breathing and working temperature in the protection suits would be about five degrees, or even zero degree or lower if it were really necessary, should the chemical filters be inefficient. In this case the suit wearers would be wearing winter clothing. They would be relying on virus inactivation at -20 Centigrade, but the air The number and the lengths of the air cooling tubes to be used may be determined by the required breathing and working temperature and according to the ambient air temperature.

This description of the invention and as presented in the drawings Figure 1 and Figure 2, includes five air cooling tube bundles of varying lengths 9.

The diameter of the air cooling tubes and their number in a bundle may partly depend on the probability of frost forming within these tubes, as encountered by experience. However, in very hot countries such as Iraq, there is not likely to be much humidity in the air during the summer months, when the refoge''.ation unit is most needed.

The bundle of cooling tubes of length 35 centimetres, drawing indication 5, Fig 1, is longer than the others, in order to provide a lower temperature of the air within this bundle, in order to help to create a direction of air flow, due to the extra weight of this lower temperature air, together with the weight effect of this extra quantity of air, relative to the temperatures and the quantities of the air in the following bundles of air cooling tubes, this extra weight pushing the preceding quantities of air along the path of air circulation.

The lengths and the number of the air cooling tubes that are to be placed in various types of refrigeration units, will be chosen according to the conditions of use such as the various possible ambient air temperatures, or other considerations. In this description, and according to the drawings Figure 1 and Figure 2, the lengths of the fn/e tube bundles are 35 centimetres for indication 5, Fig 1, then 30 centimetres, 25 centimetres, and 20 centimetres. The air cooling tubes 43 Fig 1 are for cooling used air for expulsion from the protection suit.

A tube length of 35 centimetres is expected to lower the air temperature in this length of tubes by 35 degrees Centigrade in three and or four seconds, by suitable metallic connection to the liquid air reservoir that is at a temperature of minus 190 degrees centigrade. to.

An automatic, electronic or manual choice of the cooling tube bundles within a refrigeration unit to be used, in relation to an ambient air temperature, may be made by the operation of on/off valves that may be placed at one end or at each end of the air cooling bundles, thus allowing or preventing air to enter each bundle, and allowing or preventing a circulation of air.

Perhaps the best means of valve operation would be an electronic system that detects the temperature of the ambient air and adjusts the valves automatically, after calculating the best combination of tube numbers and tube lengths.

A mechanical automatic valve adjustment means is hereunder described, which includes an over-riding manual means of valve adjustment, according to a thermometer reading by the suit wearer, of the ambient air temperature.

A suitable example of possible ambient air centigrade temperatures and use of cooling tubes and results, and use of warming tubes and results, while using a virus inactivation temperature of minus twenty degrees centigrade, may be as follows; 11.

Cooling tube Result Warming tube Result A.Air CT R CT R CT R CT R AT R Ul R US R _35O 30o -25 -20 +30 +20 +10 +60o-35o+25o-30o -5 -25 -30 +30 0 +20 +20 +550-35 +20b-30 -10 -25 -35 +30 -5 +2Q +15 +50 -35 +t5 -30 -15 -20 -35 +30 -5 +20 +15 +45 -35 + 10 -30 -20 -20 -40 + 30 - 10 +20 + 10 +40 -35 +5 -25 -20 +30 +10 +10 +20 +35o 35O 0 -20 -20 +30 +10 +10 +20 +30 30 0 -20 -20 +30 +10 +10 +20 +25 -25 0 -20 -20 +25 +5 + 10 + 15 +20 -20 0 +20 +20 + 15 25 10 20 30 + 15 15 + 15 0 + 10 + 10 +10 -30 -20 +10 -10 +10 0 +10 +10 +5 -25 -20 +5 -15 +5 -10 +5 _5O Go -20 -20 0 0 -5 -20 -25 So 20 -5 -15 -5 -10 - 10 -20 _30O 10 -20 - 10 - 10 -150 _20b _35b -I 5 -20 -1 5b 5O The ambient air inlet 31 Figure 2 to air warming compartment 27 Figure 2, as welt as the ambient air outlet 32 Figure 2, should no doubt be as large as possible to provide a maximum inflow of warm air and thereby a maximum warming action to the filtered air.

In order to provide an air intake rate for breathing of 15 litres of air per minute, it is necessary to provide for the expulsion of the same quantity of air per minute.

Two used-air flexible tube inlets or channels within the protection suit material, placed at about face level on each side of the suit, may join up into one tube that leads to the top of the tube box, at the intake nozzle and open/closed valve 42 Figure 1,fitting over or within the metal usedair expulsion tube 45 Figure 1.

Used air expulsion tube 45 Figure 1 is in suitable contact with the liquid air reservoir 7 Figure 1. The air within this tube, which may contain a bundle of air cooling tubes 43 Figure 1, therefore cools and becomes heavy, and therefore sinks to the lower part of the tube box and through the air outlet valve and flexible tube air outlet nozzle 46 Figure 1, to which is connected a flexible tube, to carry this used air to the exterior of the protection suit., by means of an air outlet nozzle fitted into a part of the suit material.

It is expected that an internal diameter of five or six centimetres, or a cross- section area of 30 to 40 square centimetres, will permit an air expulsion rate of about twenty litres of air per minute, if the length of the metal expulsion tube 45 Figure 1 is about 35 centimetres.

The rate of air expulsion may be regulated by progressive on-off valves at the two air intakes of the used air expulsion tubes at head level, and by a progressive on-off valve at the used air expulsion outlet 46 Figure 1 on the tube box. 13.

The operation of the tube end valves, such as 11, Figure 1, may be manual or automatic. Their operation may by linked to an electronic system or it may be very simple.

One example of a simple open-closed valve for the tube ends would be a valve consisting of two discs, that would usually be in a horizontal position, through which a number of holes have been drilled, or slots formed. One of these discs may be fixed to the array of tube ends, while the other disc may be free to rotate upon the surface of the Wed disc, around a central pin which extends to a valve control on the outside surface of the tube box, such as 13, Figure i. The Valve control may be in the form of a manually fumed button, that when turned slightly will cause the rotating disc to rotate over the fixed disc, acting through the vertical pin. In an open position the holes or slots in both the fixed disc and the rotating disc will coincide' permitting air to enter or to leave the tube ends, while when the valve is in a closed position the holes on the two adjacent discs will not coincide, thus preventing air from passing through these holes. A bundle of tubes may have one or two such valves placed at each end of the bundle, the central pin passing through the bundle to the lower end. An inner central pin may pass within an outer central pin to extend from a second valve to a second rotating button, placed over a lower button.

It may be possible to provide simple valves that open automatically, according to the temperature of the air that is near the valve. This would involve the provision of a metal coiled spring, usually horizontally placed, one end of which would be Fred to a central pin, near the two adjacent discs, and the other end of the coiled spring would be fixed to a vertical pin or stud that is fixed to the array of tube ends, so that if the spring should tighten or loosen, the rotating disc will rotate slightly, thus opening or dosing the valve. The coiled spring may be made of suitable metals that are highly subject to expansion according to temperature, so that variations of temperature will open or close the valve by causing the rotating disc to turn slightly. The coils of the spring may have an unwound distance between them of about one half centimetre, and the length of spring, within an area of about 36 square centimetres, may be about one hundred centimetres. This length of spring should provide an expansion and contraction variation of two or three millimetres, and the edge of the rotating disc will therefore move through this distance of two or three millimetres, thus opening or closing the valve, when there is an appropriate variation of temperature. The type and quality of the metal in the spring will be chosen according to the temperature at which the spring is required to expand or contract. In one or two cases, such as drawing indication 36 Figure 2, air may pass from one compartment to another within the tube box by the placing of vertically positioned adjacent discs on a vertical partition, with a part of the circumference of the rotating disc or a wheel that is geared to it, protruding at the top surface of the tube box, so that the valve so formed may be manually controlled. This valve arrangement may also be provided with one or two spring coils, so that this valve may also be operated automatically according to the temperature of the air.

The kind of metal used in the spring coil and its quality, may determine the temperature range over which the valve is meant to operate. The positioning of two valves on an array of tube ends will permit valve control over two temperature ranges, one valve control being fitted within another, air being either excluded or admitted.

In one possible arrangement, when a valve control such as 13 Figure 1 has been slightly pulled away from the tube box, or lifted, thus disengaging the lower end of the central pin from the rotating disc, the automatic coil spring will operate freely. For manual control, the valve control will be pushed downwards to engage into the rotating disc The manual control button will be turned to a required position, and it will then be locked in this position by the application at the top of the tube box of a sliding locking stud or pin or a pivoted lever. 15.

The refrigeration unit may be connected to the full-protection suit, or to a light protection cape or hood, or to a face mask, by a flexible air intake tube at the air intake nozzle and on-off valve 1, Figure 2, and the refrigeration unit will also be connected to such clothing by a flexible used-air expulsion tube at the air outlet nozzle and on-off valve 46 Figure 1. These flexible tubes may be connected to the refrigeration unit and to this clothing by threaded nozzles or by nozzles of the push and pull type or by other suitable means.

When the refrigeration unit is being used with a full-protection suit, a chemical and viral air filter may be placed within the material forming the protection suit, at a convenient position, such as behind the neck, extending from the left to the right shoulder. The frame of this air filter may be of supple plastic, that will not prevent the protection suit from being folded for packing. The filter may be permanent, or it may be of the cartridge replaceable type.

The area and the volume and the density of this filter, as for the identical filter that is integrated on the refrigeration unit, may be such that ambient air may naturally permeate through it at a rate sufficient for very easy breathing when the wearer is undergoing very heavy exertion. An air intake area of 20 x5 square centimetres may permit a natural air flow rate of sixty litres per minute. At this rate there will be no breathing effort or resistance to the necessary drawing into the suit of filtered air at a rate of fifteen litres of air per minute, through ducts of cross section area of 25 square centimetres.

The surface area of the air intake of the protective clothing filter and of the filter on the refrigeration unit, may be covered with a sheet of supple plastic, of a slightly 16.

larger surface area, to give protection from rain, sand and dust. This supple plastic protection panel may be held a short distance above the air intake by a number of studs about one centimetre high. Air will enter the air intake at the edges of this sheet of plastic, which edges will cover a plastic rim on the clothing, about one centimetre high, or the rim may cover the edges of the plastic sheet, in such a way that rain cannot enter the air intake. There may be an exchangeable dust and sand filter or cloth over the air intake.

The filter may consist of a compartment that may hold a filter cartridge, or it may contain a quantity of chemical material and perhaps air drying material. A mesh may hold this material above a well, two or three centimetres deep, of the same surface area as the air intake, so that a quantity of air is always freely available, above an air duct holding a flexible tube nozzle, to which the flexible tube will be connected, that will lead to the refrigeration unit air intake nozzle and on-off valve, drawing indication 1, Figure 2.

The filtered air from the full-protection suit filter may enter the integrated filter on the refrigeration unit, drawing indication 2, Figure 2, that is mainly for operation when the refrigeration unit is being used under a light hood or a face mask.

An example of the operation of the refrigeration unit will non be described, with further reference to the drawings Figure 1, and Figure 2.

The filtered air is ducted by air duct 3, Figure 2, from the integrated air filter to the open top ends of the metal air cooling tubes 4,Figure 1, which may be bunched by means of a metal tube or a parallelepiped 5, Figure 1. Air duct 3, Figure 2 may contain a pumping device and a source of energy, such as an accumulator, or such equipment may be placed elsewhere in the tube system, if such equipment is specially required. 17.

The air cooling tubes 4, Figure 1, and the bunching tube 5, Figure 1, are in contact with the metal cooling jacket or collar or clasp, 6, Figure 1, which contact is arranged, by quantity of metallic material and by suitable insulation, to transfer from the liquid air reservoir to the air cooling tubes a temperature of about minus 40 Centigrade.

Therefore, the air that is ducted from air duct 3, Figure 1, to the open top ends of the air cooling tubes 4, Figure 1, will become cooled and will sink into the cooling tubes, and through the cooling tubes, leaving them at the lower ends, 8, Figure 1. If as expected the rate of air cooling is one degree centigrade for every centimetre length of air cooling tubes 4, Figure 1, through which the air sinks, these tubes 4, Figure 1 having a length of centimetres, the enclosed sinking air will have lost 35 degrees of heat at 8, Figure 1.

Sinking quantities of air within the air cooling tubes 4, Figure 1, will force lesser quantities of air to rise within the air enclosing tube or enclosing parallelepiped 9, Figure 1, and to reach air outlet 10, Figure 1.

The air rising and spilling from air outlet 10, Figure 1, may enter air intake valve 1 1, Figure 1, on air cooling tubes 12, Figure 1, if this valve has been opened by use of valve control 13, Figure 1.

The use of valve control 13, Figure 1, will depend on the temperature of the ambient air that is entering the refrigeration unit If this temperature is +60 centigrade, the air that has passed through cooling tubes 4, Figure 1, is now at +25 centigrade, its temperature having been lowered by 35 degrees C. A temperature of +25 C. is usually a convenient breathing and working temperature, and if the refrigeration unit is being used only as a means of refrigeration, 18.

and not also as a means of protection from bacteria and viruses, by coldinactivation, then the cooled air may be allowed to flow from air outlet tO, Figure 1, to air outlet 14, Figure 1, the air inlet valve 15, Figure 1, on the cooling tubes 16, Figure 1, and the air inlet valve 17, Figure 1, on the cooling tubes 18, Figure 1, remaining closed.

The air at the convenient temperature of +25 C. will flow from air outlet 14 Figure 1, on cooling panel 19, Figure 1, to the air inlet 20, Figure 2, on the air warming panel 21,Figure 2, and the three groups of air warming tubes such as 26 Figure 2, and 35, Figure 2, running through the air warming compartment 30, Figure 2,will not operate, their valves such as 28, Figure 2, and 33, Figure 2, remaining closed. The air at +25 C.

will pass through open valve 37, Figure 2, controlled by valve control 38, Figure 2, and it will rise by antecedent pressure to air inlet 39, Figure 2,and it will enter the protection suit air supply tube 40, Figure 2.

One aim of this refrigeration unit specification is to provide protection in warfare and in terrorist situations from chemical and viral action. It is conjectured that if the air that is breathed in the protection suit is brought to a moderately low level, such as minus 20 centigrade, for about five seconds, and then re-warmed for comfortable breathing, are bacteria and viruses in this cooled air might be inactivated for up to two hours, the maximum time that this air is likely to circulate within the expanded form of the suit, before being expulsed.

The temperature of the air in the refrigeration unit may be lowered to minus 20 C.

and then suitably re-warmed by the operation of several bundles of air cooling tubes and by the use of re-warming tubes. t9.

If the ambient air temperature is +60 centigrade, it is expected to be lowered through 35 degrees to f25 C., according to some estimates, by the operation of the air cooling tubes 4, Figure 1. If the length of the air cooling tubes t2 Figure 1 is 30 centimetres, the temperature of the air that passes through air cooling tubes t 2 Figure 1, may be lowered from + 25 . to minus 5 C. This air, pushed upwards by the larger quantities of heavy falling air in cooling tubes 5, Figure 1, and t 2, Figure 1, will rise from the lower ends of cooling tubes 12, Figure 1, to the air outlet 22, Figure 1, of the air enclosing tube 23, Figure 1, and this air at minus 5 C. will spill onto the open or closed air entry valve 15, Figure 1, of air cooling tubes 16, Figure 1.

The operation of the air cooling tubes 16, Figure 1, will lower the air temperature by 25 C., the length of this group of tubes being 25 centimetres, and the temperature of this air will then be minus 30 centigrade.

A temperature of minus 30 C. may sufficiently inactivate bacteria and viruses for a period of time. This air may therefore be allowed to pass to air outlet 14 Figure 1, of the air cooling panel 19 Figure 1, the valve control 24 Figure 1 of the air cooGng tubes 16 Figurer remaining open, and the valve control 25 Figure 1 of air cooling tubes 18 Figure 1, remaining closed.

This air coming from the air outlet 14 Figure 1, of the air cooling panel 19, Figure 1, at a temperature of minus 30 C., and flowing into the air inlet 20, Figure 2, of the air warming panel 21, Figure 2, will rise through the lower ends of the air warming tubes 26, Figure 2, and this air will pass through the open or closed air valve 28, Figure 2, the valve control 29, Figure 2 being open. 2D.

Most of the length of the air warming tubes 26, Figure 2, passes through the air warming compartment 27, Figure 2. The air warming compartment 27, Figure 2, is warmed by ambient air that is drawn through air intake 31, Figure 2, by a lowering of the temperature of this ambient air in the air warming compartment 27, Figure 2, due to the low temperature of the air at minus 30 C. that is rising within the air warming tubes 26, Figure 2, while gaining heat and losing density. This ambient air that is drawn through air intake 31, Figure 2, sinks from air outlet 32, Figure 2, having lost heat and gained density, thus drawing in further quantities of air at the air inlet 31, Figure 2.

If the temperature of the ambient air entering the air warming compartment 27, Figure 2, is +60 centigrade, the air that is rising within the air warming tubes 26, Figure 2, at a temperature of minus 30 degrees centigrade, may gain about 30 degrees of heat when passing through a warming tube length of 30 centimetres, and the temperature of this air when leaving the warming tubes 26, Figure 2, will then be at about 0 centigrade.

This air will have an increasing tendency to rise within the warming tubes as heat is gained, and it will spill from the open outlet valve 28, Figure 2, onto the open air valve 33, Figure 2, that is over the top ends of the air warming tubes 35, Figure 2, and that is controlled by valve control 34, Figure 2 This air at 0 C. will be pushed down by pressure from greater quantities of air within this tube system, through the twenty centimetre length of the air warming tubes 35, Figure 2, and it will therefore gain about twenty degrees of heat to acquire a temperature of +20 centigrade To permit this air pressure, the valve 36, Figure 2, will remain dosed. 2'1.

Air at +20 Centigrade is at a convenient temperature for breathing and working, and this air may therefore pass from the lower ends of the air warming tubes 35, Figure 2, to the valve in the open position 37, Figure 2, controlled by valve control 38, Figure 2.

This air will then pass into the air inlet 39 Figure 2, and to the protection suit air supply tube 40, Figure 2. A flexible tube will duct this filtered clean air from the tube nozzle and on-off valve 41, Figure 2, to a suitable part of the protection suit, or to a light protective blouse, or cape, or face mask. If the protection suit is being worn, the cool clean air may be directed towards the lower part of the suit, from whence it win circulate by acquired warmth to the head area.

Two air intakes placed into the suit material, one on each side at head level, controlled by graduated on-off valves, may duct used air by means of two flexible tubes, which may combine into one tube to fit to air intake nozzle 42, Figure 1, on the refrigeration unit, which also forms an open-closed valve operated by screwing or by other means.

The used air in the suit may be drawn into and through the metal air cooling tubes 43, Figure 1, by the loss of heat of the air within these tubes, due to the low temperature of the metal tubes, and that of the metal bunching tube or holding tube or clasp 44, Figure t, this metal being in contact with the metal cooling jacket 6, Figure 1, and the liquid air reservoir 7, Figure 1. The lowered density of this cooled air mill cause it to sink down the air cooling tubes 43, Figure 1, and down the metal used-air expulsion tube 45, Figure 1, to the open or closed air outlet valve and flexible tube air outlet nozzle 46, Figure 1. The flexible tube in nozzle 46, Figure 1 will connect to a nozzle for air expulsion on a suitable part of the suit. Any suitable material may be used in the place of the use of metal for the construction of the refrigeration unit. 22.

In one possible example, when the liquid air in the metal liquid air reservoir 7, Figure 1, has been wholly or partly consumed, it may be replenished by an exchangeable supply flask 47, Figure t. A rise in temperature within the liquid air reservoir 7, Figure 1, or at any suitable part of the unit, due to a diminished quantity or an absence of liquid air, will cause a supply tube 49, Figure 1, to expand in length through a distance of one or two millimetres, thus operating the outlet of a spring-held ball-and-socket valve nozzle 50, Figure 1, thereby allowing the liquid air in the supply flask 47 Figure 1 to enter the expanded supply tube 49, Figure 1. This supply tube will duct the liquid air from the supply bask to the liquid air reservoir 7, Figure 1.

When the presence of a quantity of liquid air in the reservoir causes the supply tube 49, Figure 1, to contract, it wilt no longer be in contact with the ball-and-socket valve of the contact nozzle 50, Figure 1, and the spring will operate to dose valve 50, Figure t, thus stopping the supply of liquid air to the reservoir 7, Figure 1. Alternatively, the contact nozzle 50, Figure t, may be provided with a pawl and ratchet arrangement which wlil hold the expanded supply tube 49, Figure 1, in the contact nozzle 50, Figure 1, so that the contact nozzle 50, Figure 1 may remain open, to empty the liquid air supply flask 47, Figure 1. The contracted supply tube 49, Figure 1, will therefore cease to be in contact with the floor of the liquid air reservoir 7, Figure 1, having contracted. When the supply flask 47, Figure 1, has been emptied, the rise in its temperature may be arranged to release the supply tube 49, Figure 1, from its fixed position in contact nozzle 50, Figure 1, by a release of the paw and ratchet arrangement. Suitable air pressure valves may be provided within the liquid air reservoir 7, Figure 1, and within the liquid air supply flask 47, Figure 1. The nozzle valve 50, Figure 1, may be hand operated by pressure on a button, in order to fill the liquid air reservoir 7, Figure 1, by manually emptying a supply flask.

Another preferred liquid air supply flask and refrigeration unit refilling arrangement is to manufacture the exchangeable liquid air supply flask, drawing indication 47, Figure 1, so that it may fit within the liquid air metal reservoir 7, Figure 1, and so that once the supply flask has been fitted into the metal reservoir, it performs the function of the reservoir.

The exchangeable supply flask that fits into the reservoir may consist of a metal flask entirely covered with insulating material, for safe handling at all times. The flask may if necessary be provided with a pressure valve to prevent a variation of gas pressure within the flask according to the variation of the level of liquid within the flask. One end of the flask may be provided With an inlet automatic refilling stopper, kept in place by a strong spring, so that great numbers of supply flasks may be automatically refilled at a central point by machines operating at high speed. The other end of the flask may be provided with a tube that extends from the centre of that end of the flask, and for some distance into the flask. This tube may be open at the end surface of the flask and closed at the end of the tube that is within the flask, so that when the supply flask is placed within the metal reservoir, this internal tube may enclose a stub or a stud that may be placed at the central point of the floor of metal reservoir 7, Figure 1. This metal stub or stud may remain in contact with the metal tube of the flask, so that heat from the liquid air within the flask may automatically transfer to the metal reservoir 7, Figure 1. Allowance may be made for the internal metal tube being in a contracted state when the supply flask contains liquid air, while the stub or stud may be in an expanded state if the metal reservoir 7 Figure 1 is empty. Any such problem may be overcome by providing stubs or studs that are in two or three or four vertical sections that converge slightly and that have some freedom of spring movement towards the point of convergence, so that the internal tube may always fit / Z4.

easily over the stub or stud and always make a close fit. In this arrangement of a supply flask, there is no need to provide an outlet on the Bask for the liquid air. As heat is transferred to the refrigeration unit, the liquid air will boil, and the bolted air will pass through the provided pressure valve. The supply flask may be placed into the refrigeration unit by sliding open a spring held plate that covers the metal reservoir 7, Figure 1, and by inserting the flask into the reservoir, or by any other suitable means. A number of reserve basks may be carried in case of need.

The usual operation of the refrigeration unit will of course also take place in ambient air temperatures that are often much lower than that of the preceding example of f 60 Centigrade.

If the ambient air temperature is +35 centigrade, it will enter air cooling tubes 4 Figure 1, of length 35 centimetres, and leave the air outlet 10 Figure 1 at 0 Centigrade.

This air will enter air cooling tubes 12 Figure t, of length 30 centimetres, and it will leave the air outlet 22, Figure 1, at Sirius 30 Centigrade. Air valves 15, Figure 1, and 17 Figure 1, being closed, the air will leave air outlet 14 Figure 1, and enter air inlet 20, Figure 2. This air may enter the air warming tubes 26, Figure 2, of length 30 centimetres, and pass through open air valve 28, Figure 2, at 0 Centigrade. The air may pass through air valve 33, Figure 2, and leave the air warming tubes 35, Figure 2, of length 20 centimetres, at a temperature of +20 Centigrade. Air valve 37, Figure 2, being open, the air at +20 centigrade will enter the air inlet 39, Figure 2, and the protection suit air supply tube 40 Figure 2.

With the acquisition of manufacturing and production experience, it might be possible to produce these refrigeration units with dimensions of about 20 centimetres by centimetres, x 10 centimetres, or about 8 inches x 8 inches x 4 inches. 25.

Claims

Claims.

1. A refrigeration unit which may operate by means of a liquid gas and particularly by liquid air, and which operates conjointly by means of ambient gas or ambient air, by which means a useful circulation of quantities of ambient gas or air is set in motion within an enclosed volume, which may be filtered for any particular purpose such as for safe breathing, there being provision for the temperature of the ambient gas or air being suitably lowered to a controlled temperature for any particular purpose such as the inactivation of bacteria and viruses, and there being provision for the temperature of the ambient gas or air being suitably raised to a controlled temperature for any particular purpose such as for comfort in breathing and in working within the enclosed quantities of ambient gas or air; there being means for cooling the ambient gas or air in the form of air or gas cooling tubes, of defined length and thereby of defined cooling capacity, by direct or indirect connection or proximity to the cooling capacity of a natural source of low temperature such as liquid gas or liquid air, and there being provided means for conveniently warming cooled ambient air or gas, in the form of air or gas warming tubes of defined lengths and warming capacities, which ambient air or gas may be warmed and filtered for breathing and working, by direct or indirect connection or proximity to a natural source of warmth, such as warm ambient air, the gas flow or air flow being produced by the effects of density variations in quantities of air or gas within a system of tubes and confined spaces within the refrigeration unit, resulting from the produced temperature variations and their gravity effects, by which variations a useful circulation of processed air or gas is derived, which may be derived entirely by these applications of natural effects. 26.

2. A refrigeration unit as in Claim 1, which is provided with an air intake tube and an air expulsion tube, for connection to protective clothing when the unit is within protective clothing, such as a protection suit or a protection envelope, which refrigerated clothing providing protection from seasonal heat in working conditions, and in battle conditions which might last for several days, and providing protection by the low temperature inactivation of bacteria and viruses such as ebola, sars and anthrax; and for connection, also, to protective clothing such as light blouses, capes and hoods, and light face masks or gas masks, for the carrying out of work, which may be office work or administrative work, and duties, when protection from heat and from chemicals and bacteria and viruses is required or likely to be required.

3. A refrigeration unit as in claims 1 and 2, that is provided with means to accommodate a pumping device and its source of energy such as an accumulator, or a power line, for air or gas circulation, for use when a particular application of the refrigerator unit, or a particular industrial application, entails this requirement.

4. A refrigeration unit as in claims t, 2, or 3, wherein the refrigeration unit has the general form of a box, composed of two panels of similar dimensions, one panel being a cooling panel and the other a warming panel, that are separated by an insulation sheet, this box being composed of metal such as aluminium or another suitable material, which may be conveniently constructed by die- casting or by other means, the internal form of the box permitting paths of circulation of ambient air or gas, which paths including, a large surface area chemical filter and chemical air dryer, which may be in the form of a cartridge, 27.

a well or reservoir for air that has permeated through the filter, an air duct for ducting permeated air to the cooling panel, and to one of a number of air cooling tubes of graduated lengths, each providing a different temperature, being directly or indirectly connected to a source of tow temperature, which may be transferred to the cooling tubes, one or a number of air enclosing tubes, which may enclose the air cooling tubes and which provide an air outlet for the path of air circulation; automatically or manually operated valve controls, which admit or prevent air from passing through selected air cooling tubes, an air outlet from the cooling panel to an air inlet on the warming panel, one or a number of bundles of air warming tubes of suitable material, being graduated in length to impart different temperatures to the air passing through them; automatically or manually operated valve controls which admit or prevent air from passing through selected air warming and cooling tubes; an air outlet to a clean air metal supply tube, which leads to a clean air outlet valve and a nozzle for a clean air flexible supply tube.

5. A refrigeration unit as in Claims 1,2, 3, and 4, in which there is provided a liquid air reservoir of metal or of a suitable material, which may be insulated to limit and control the amount of heat that is transferred to the air cooling tubes, which liquid air reservoir including an air pressure valve, and a metal liquid air supply tube of suitable expansion qualities, which may expand when there is a lack of liquid air in the reservoir' and which when expanded may contact and open a liquid air outset noble, operated by a spring held hall and socket arrangement, on a portable liquid air supply flask that may be clipped onto the refrigeration unit. The opening of the liquid air outlet nozzle on the supply flask permitting liquid air to run down the expanded supply tube and into the liquid air reservoir. The supply tube having contracted, it may be held in place within the supply flask outlet nozzle by the action of a pawl and a ratchet, until Z8.

the supply flask has been emptied, when a rise in temperature of the supply flask will release the supply tube from the pawl and ratchet arrangement, a spring around the supply tube then withdrawing the supply tube into the refrigeration unit.

6. A refrigeration unit as in claims 1,2,3,4, and 5, provided with a portable and exchangeable liquid air supply flask, which may be securely fixed on the top of the refrigeration unit, and which may be provided with means of automatic filling in a supply depot; being provided with an air pressure vane, and with a button for manually releasing the liquid air into the liquid air reservoir of the refrigeration unit.

7.A refrigeration unit as in Claims 1,2,3,4,5,and 6, being provided with a circulation system for the use of warm ambient air, in order to warm air that has been filtered and cooled to inactivate bacteria and viruses, the warm air circulation system induding a warm air intake, a warm air compartment within the refrigeration unit, and a warm air outlet. Various lengths of tubes duct clean cooled air through the warm air compartment, thus warming the cooled air and cooling the warm ambient air, which then sinks to the air outlet because of its increased density, causing further quantities of ambient air to enter the warm air intake.

8.h refrigeration unit as in Claims 1,2,3,4,5,6, and 7, which may be provided with valves and valve controls, being either automatically or manually operated. The valves allow or prevent air in the cooled air circulation system from passing through cooling tubes' and warming tubes, in order that required low air temperatures may be selected, and so that warm air temperatures may be selected, so that in case of viral attack, the 29.

clean air temperature may be lowered to minus twenty degrees centigrade, to inactive viruses for some time, and so that this air may then be warmed to plus twenty degrees centigrade, for comfortable breathing and working. A simple mechanical valve may be formed by the juxtaposition of two discs which cover the bundles of cooling tube ends and warming tube ends. One disc may be fixed to the bundle of tubes, and the other may revolve over the fixed disc by means of a central pin or spindle, which may extend to a revolving control button on the top of the refrigeration unit. Holes may be drilled or slots may be formed through both discs, so that in one position the holes in both discs will coincide and allow air to pass through them, but if the revolving disc is turned slightly, the holes will no longer coincide, and air will be prevented from passing This disc operation may be automatic or manual. A simple arrangement for automatic disc operation being the provision of a coiled spring of suitable expansion material over the disc valves, one end of the spring being fixed to the array of tube ends, and the other end of the spring being fixed to the central pin or spindle that causes the revolving disc to turn, so that any particular air temperature will cause the spring coil to expand or to contract, thus fuming the revolving disc through a distance of two or three millimetres to a required position relative to the fixed disc. The control button on the top of the refrigeration unit may be pulled upwards slightly to disengage the manual control button from the central pin or spindle when automatic valve control is required. When manual valve control has been selected, the chosen control button selections may be socked by the use of a locking stud or locking pin that blocks the control button. Two valves may be placed one above the other, the upper valve control parts operating over the lower valve control parts, one central spindle being positioned within the other, in order to provide for the valve control of two temperature ranges. The two disc valve arrangement may be placed against compartment partitions, either horizontally or vertically, in order to allow or to prevent gas or air from passing through the valve. 30.

9. A refrigeration unit as in Gaims f to 8, that is provided with a metal used-air expulsion tube, which enc oses one or a number of air cooling tubes that are cooled by direct or indirect contact with the metal liquid air reservoir. Air within these cooling tubes is thereby cooled, its density is thereby increased, thus causing, it to sink through the usedair expulsion tube to an expulsion valve and a nozzle for a flexible air expulsion tube, through which the air may pass, to a tube nozzle and air outlet valve on the protective clothing, thus causing ambient air to be drawn into the protection suit and into the refrigeration unit through the large area air intakes.

10. A refrigeration unit as in Claims 1 to 9, including a large area type of air intake for the intake of air for gas mask chemical filtration, that does not therefore depend on energy and effort from thorax inhalation for the inflow of air through the chemical filter, since the large area of the air intake permits air to permeate through the fitter, therefore becoming freely available to, the breather in abundant quantity, and without any particular physical effort.

11. A unit for the processing of gas or fluids, by filtration, or temperature control, or by other means, in the form of mainly confined spaces or mainly enclosed volumes, such as a system of conveniently arranged tubes within a mainly enclosed volume, being mainly in a vertical position in relation to the direction of a pull of gravity, which unit may be placed or constructed in an atmosphere or within some fluids, and which may include a source of relatively low temperature, which may be a liquid gas, such as liquid air, which may be arranged by direct or indirect contact or proximity, to cool to a defined temperature a number of gas or fluid cooling tubes, through which may pass the gas or the fluid to be cooled, and which may be arranged to warm to a defined temperature a number of gas or fluid warming tubes, through which may pass the gas or fluid to be warmed, the required temperature being defined by a choice and selection of cooling or t 31.

warming tubes according to their length and therefore their potential for the transmission of heat,by means of the operation of valves controlling the access of the atmosphere or the fluid to some or all of the cooling and warming tubes; there being within the unit at least two paths of circulation, at least one path of circulation being for quantities of atmosphere or fluid intended for the accomplishment of useful work or action, and which may therefore be conveniently processed by filtration, by the application of heat or low temperature, or by other means, and at least one other path of circulation being for quantities of atmosphere or fluid which lead to or form part of the accomplishment of the useful work or action, by means of the application to the unit and its purpose of the relative inherent natural quality or state of the atmosphere or fluid, whereby atmosphere and fluid intake circulations may be produced, and atmosphere and fluid expulsion circulations, and atmosphere and fluid processing circulations, by the production within the paths of circulation of the unit, of quantities of the atmosphere or fluid, having relatively increased or decreased densities, obtained by the controlled temperature variations, causing a reaction relative to gravity, or artificial gravity such as centrifugal force, the quantities of atmosphere or fluid within the paths of circulation either rising or sinking relative to the ambient quantities of atmosphere or fluid, a direction of flow thus being obtained within the paths of circulation of the unit, this possibility of inducing a direction of flow by directly natural means being likely to be useful for any particular industrial purpose and application, and in the case of this unit, permitting the intake, the filtration, the refrigeration, the re-warming, and the expulsion of quantities of air, for the refrigeration of protective clothing and its wearer, and for safe breathing 12. A refrigeration unit provided with a supply means for liquid air that is a preferred alternative to the means described in claims five and six, whereby the exchangeable liquid air metal supply flask, entirely covered with insulating material for safe handling, may be fitted into the metal reservoir forming a part of the refrigeration unit, the metal part of the supply flask thereby being in contact with the metal of the reservoir, and thereby functioning as a part of the liquid air reservoir, the supply flask being if necessary provided with a pressure valve to prevent a variation of gas pressure within the flask according to the variation of the liquid level within the flask; one end of the Bask being provided with an inlet automatic refilling stopper! kept in place by a strong spring, so that great numbers of supply flasks may be automatically refilled at a central point by machines operating at high speed, the other end of the flask being provided with a tube extending from the centre of that end of the flask, and for some distance into the flask, being open at the end surface of the Hask and closed at the end of the tube that is within the flask, so that when the supply flask is placed within the metal reservoir, the internal tube may enclose a stub or a stud that may be placed at the central point of the floor of the metal reservoir, this metal stub or stud remaining in contact with the metal tube of the flask, so that heat from the liquid air within the flask may automatically transfer to the metal reservoir, allowance being made for the internal metal tube being in a contracted state when the supply flask contains liquid air, while the stub or stud may be in an expanded state if the metal reservoir is empty; this problem being overcome, in one way, by the provision of stubs or studs that are in a number of vertical sections, such as three or four, that converge slightly and that have some freedom of spring movement towards the point of convergence, so that the internal tube may always fit easily over the stub or stud and may always make a close fit In this arrangement of a liquid air supply flask, there being no need for the provision of an outset on the flask for the liquid air to flow into the liquid air reservoir, since this become unnecessary, the heat being transferred by the metal in contact. The liquid air supply flask may be placed into the refrigeration unit by the sliding open of a spring held plate that may cover the aperture of the metal reservoir, and by the insertion of the supply flask into the reservoir, or by any other suitable means, a number of reserve supply flasks being carried in case of need.

13. A refrigeration unit substantially as described in Claims 1 to 12.

Amendments to the claims have been filed as follows Claims.

1. A machine, devoid in operation of moving parts, designed to operate as a refrigeration unit, operating by means of supplied energy in the form of quantities of liquid gas and particularly liquid air, to effectuate work by the combined application of several natural means, that are heat conduction, convection, gravity attraction and fluid pressure equation, this effectuated work being the circulation of air, that provides a local atmosphere, and the cleaning, cooling and warming of air for convenient breathing and for body comfort within the local atmosphere.

2. A machine operating as a refrigeration unit as in Claim 1, which operates by the natural displacement of ambient air into and from the confined spaces of tube systems, tube enclosures, and protective clothing.

3. A machine operating as a refrigeration unit as in Claims 1 and 2, in which a chemical air filter is provided in the pathway of incoming ambient air in order to eliminate bacteria and viruses, and harmful chemicals and substances, and which in some versions, subjects bacteria and viruses to air at an arranged low temperature in view of their conjectured elimination by the effect of cold.

4. A machine operating as a refrigeration unit as in Claims 1, 2, and 3, which effectuates work by carrying out a required treatment of ambient air by cooling, and by cleansing, and subsequently by warming, and by the provision of a local atmosphere within protective clothing, for breathing and for body comfort, and by the evacuation of used local atmosphere air. 3w

5. A machine operating as a refrigeration unit as in Claims 1 to 4, which provides for the cooling of ambient air by means of cooled tubing that is cooled by the conduction of a required amount of heat from liquid gas, by means of the provision of a required amount of conducting material and insulating material in the form of a cooling jacket or clasp, through which tubing passes the ambient air, the required amount of air cooling being obtained in proportion to the length of the tubing, according to an estimate of one degree of air cooling per one centimetre length of tubing.

6. A machine operating as a refrigeration unit as in Claims 1 to 5, which provides for the suitable warming of cooled clean air by the provision of a warming compartment, through which passes tubing for the passage of cooled clean air, the amount of warming being in proportion to the length of the tubing, according to an estimate of one degree centigrade of warming per one centimetre length of tubing, the warming compartment being filled with ambient air that warms the tubes containing cooled clean air, thus cooling the air in the warming compartment and causing a circulation of this warming air, from an air inlet situated at the top of the warming compartment, to an air outlet at the bottom of the compartment, due to the gravitational effect of the higher density cooled air within the warming compartment, that is caused to sink and leave the warming compartment, thus drawing further quantities of ambient air into the top inlet of this compartment.

7. A machine operating as a refrigeration unit as in Claims 1 to 6, which provides for the continuous evacuation of the local used atmosphere, and thereby for its continual replacement with a fresh atmosphere, by means of a used air evacuation tube, that is extended at its top end by a flexible tube leading to the head area of the local atmosphere for breathing and body comfort, the used air tube containing an air cooling tube of a required length, that is cooled by the contact a required amount of heat conducting material that is in contact with a liquid gas container, in the form of a portable and easily exchangeable flask, that serves as a liquid gas reservoir; the air cooling tube cooling the air within the used air tube, and so causing it to sink, and to leave the lower end of the tube, and so to leave the machine and the protective clothing, thus drawing used air from the local atmosphere and helping to cause a continuous renewal of circulating air, by the replacement of this air, entering a lower part of the local atmosphere volume through an air inlet, after passing through a filter and through the heat treatment process of the machine.

8. A refrigeration unit as in Claims 1 to 7, for use with protective clothing, protecting from seasonal heat, and from bacteria and viruses and chemical effects, by means for lowering air temperature, and by filtration means, the unit comprising the two halves or two panels of a box, one panel being an air cooling panel, and the other being an air warming panel; the air cooling panel containing an air intake with an open/closed valve; and an air filter; and an air well, and an air duct leading to one or a number of air cooling tubes, which bunch within them a number of finer tubes that by their total metallic surface rapidly transfer heat to air that is passing through these tubes, which bunched tubes in some versions being provided at their ends with intake and outlet air passage control valves and valve operation means; the air cooling panel containing a defined mass of metal contact material, being a cooling jacket, to conduct a defined amount of low temperature from a source of low temperature to the air cooling tube or tubes, the low temperature being conducted through one or a number of sudably-formed or shaped metal;nsertsthat form a part of the metallic mass, the metal inserts being inserted into the interior of a well or wells formed on a side or an end of a metallic liquid air bottle of suitable shape, which serves as a liquid air reservoir, this insertion taking place as the liquid air bottle is clipped into its position on the refrigeration unit, so that the low temperature of the liquid air may pass through the metal wall of the bottle, where it is in the form of a well, to themetal insert that fills the interior of the well and that is in contact with the metal wall of the bottle; the air cooling tubes being partly enclosed by enclosing tubes or parallelepiped shaped enclosures that retain quantities of air as the air rises to a required level or volume and then spills, to guide quantities of air from the suitable level from one air cooling tube to any other chosen air cooling tube that is at a lower level, by the effect of gravity; an air outlet from the air cooling panel to an air inlet on the air warming panel; an air warming compartment through which pass one or a number of air warming tubes, the air warming compartment receiving warm ambient air, for warming an air warming tube or tubes, which contain passing cooled air that is to be warmed; an ambient air inlet to the air warming compartment and an ambient air outlet placed at a level lower than the inlet; a direct outlet valve for use when warmed cleaned air temperature is convenient for breathing and for body cooling; a warmed and cleaned air outlet from warming panel to air inlet of protection suit air supply tube; a used air expulsion tube; a used air intake nozzle and open closed valve; a bunch of air cooling h tees within the used air expulsion the; a used air outlet valve and flexible tube outlet nozzle, a suitably shaped exchangeable liquid air supply flask; whereby there is a heat exchange between supplied liquid air and quantities of ambient air that are in the cooling tube or tubes, that are open to the atmosphere, which ambient air is drawn through the filter arid cling tubes by the gravity edect Hits lower density when cooled within a tube system, through variable temperatures, varying from plus sixty degrees centigrade to minus sixty degrees centigrade, before being warmed to a temperature of about plus twenty degrees centigrade for convenient breathing and working by means of the air warming tubes, obtaining warmth from the intake and expulsion by gravity effect of relatively warm ambient air; the expulsion of used air being obtained by the cooling and sinking within a used air intake and outlet tube of air becoming relatively heavy, thus drawing in further quantities of ambient air through the air filter at the other end of the air cleaning tube system, and completing the cycle.

9. A refrigeration unit for use with protective clothing, protecting from seasonal heat and from bacteria and viruses and chemical effects, by means for lowering air temperature, and by filtration means, as claimed in Claims 1 to 8, wherein there is provided a large area filter or filters of up to one hundred square centimetres, above a large area air well, and an air duct of suitable diameter leading to the protective clothing, the area of the air filter or the air filters, being of dimensions such that air in the quantities required for breathing under exertion and for the evacuation of body heat, naturally permeates through the filter and into the provided air well, ensuring the availability of a supply of air of sixty litres per minute for easy breathing and for body comfort, when the area dimension of the filter is one hundred square centimetres' and thus avoiding the necessity of drawing in air by thoracic exertion; the fitter being protected from rain and dust by a covering sheet of plastic positioned a short distance above the filter by studs, and-by an exchangeable dust cloth.

10. A version of the refrigeration unit as in Claims 1 to 9, being arranged to operate in an ambient air temperature of about sixty degrees centigrade, by producing a temperature within adequate volumes per minute of air for breathing and working of about twenty degrees centigrade, after the cooling of this air to a required and chosen low temperature, which choice possibly being down to minus sixty degrees centigrade, for a conjectured elimination of bacteria and viruses, by means of a suitable adjustment of the volume of metal contact material herein termed the cooling jacket or clasp, that transfers heat from the liquid air flask, to an air cooling tube of a suitable length which is devoid of control valves and valve control means, a suitable tube length possibly being one hundred and twenty centimetres, the cooling tube being arranged in a suitable manner within the tube box, for obtaining the required low temperature of the air passing through the cooling tube; and by the provision of an air warming tube of suitable length, being devoid of control valves and valve control means, a suitable tube length possibly being eighty centimetres, arranged in a suitable manner, being placed within an air warming compartment, these lengths of cooling and warming tubes altering the temperature of the air fig passing within them according to the length of the tubes, and according to an observed rate of temperature increase or decrease relative to tube length, estimated to be one degree per centimetre of tube length.

11. A version of the refrigeration unit as in Claims 1 to 10, being arranged to operate in an ambient air temperature of about forty five degrees centigrade, by producing a temperature within adequate volumes per minute of air for breathing and working of about twenty degrees centigrade, after the cooling of this air to a required and chosen low temperature, which choice possibly being down to minus sixty degrees centigrade, for a conjectured elimination of bacteria and viruses, by means of a suitable adjustment of the volume of metal contact material herein termed the cooling jacket or clasp, that transfers heat from the liquid air flask that sewes as a liquid' air reservoir, to an air cooling tube of a suitable length that'is devoid of valve controls and valve control means, a suitable length possibly being one hundred centimetres, arranged'in a suitable manner, for obtaining the required low temperature of the air passing through the cooling tube; and by the provision of anair warming tube of suitable'length, that is devoid of valve controls and valve control means, a suitable length possiblybeng eighty centimetres, arranged in a suitable manner, being placed nthin an air warming compartment, these lengths of cooling and warming tubes altering the temperature of the air passing within them according to the length of the tubes, and according to an observed rate of temperature increase or decrease relative to tube length, estimated to be one degree per centimetre of tube length.

12. A version of the refrigeration unit as in Claims 1 to 11, being arranged to operate in an ambient air temperature of about thirty degrees centigrade, the air cooling tube being of a suitable length of about ninety centimetres, and the air warming tube having a length of about eighty centimetres, these cooling and warming tubes being devoid of air passage control valves and valve control means.

13. Versions of the refrigeration unit as in Claims 1 to 12, but which rely for virus elimination not on low temperature, but on the use of the chemical filter, these version being arranged to operate at a breathable air temperature of about twenty degrees centigrade, after the cooling of this air from the ambient air temperature, either to zero degree centigrade or to twenty degrees centigrade, by the provision of one air cooling tube that is devoid of control valves and control means, being of a length of about sixty centimetres for a version to be used in an ambient air temperature of about sixty degrees centigrade, and being of a length of about forty-five centimetres for a version to be used in an ambient air temperature of about forty five degrees centigrade, and being of a length of about thirty five centimetres for a thirty five degree centigrade temperature of ambient air; the air warming tube having a length of about twenty centimetres for these three different ambient air temperature versions.

14 Versions of a refrigeration unit mainly as in Claims 1 to 13, that are provided with an air intake tube and an air expulsion tube, for connection to protective clothing when the unit is upon or within protective clothing, which refrigerated clothing providing protection from seasonal heat in working conditions, and in battle conditions which might last for several days, and in some versions providing conjectured protection by the low temperature elimination of bacteria and viruses such as ebola, sars and anthrax; and for connection, also, to protective clothing such as light blouses, capes and hoods, and light face masks or gas masks, for the almost normal carrying out of work, which may be office work or administrative work, and duties, when protection from heat and from chemicals and bacteria and viruses is required or likely to be required.

15. A refrigeration unit as in claims 1 to 14, wherein the refrigeration unit has the general form of a box, composed of two panels of similar dimensions, one panel being a cooling panel and the other a warming panel, that in a general manner are separated by an insulation material, this box being mainly composed of metal such as aluminium or plastic or another suitable material, which if necessary may be covered with an insulating material for contact and handling safety, which may be conveniently and cheaply constructed by rapid mass production die-casting or by other means, the internal forms of the box permitting paths of circulation of ambient air or gas, which paths including a large surface area chemical filter and chemical air dryer, which may be in the form of a replaceable cartridge; the box also consisting of a well or reservoir for air that can permeated through the fleer, an air duct for ducting permeated air to the cooling panes, and to one or a number of air cooling tubes of graduated lengths, each thereby providing a different temperature according-to their lengths, being directly or indirectly connected to -a source of low temperature, which may be transferred to the cooling tubes by conduction, one or a number of air enclosing tubes, which may enclose the air cooling tubes and which provide a conveniently situated air outlet for the path of air circulation; automatically or manually operated valves and valve controls, restricted to versions of the -machire that include several air cooling tubes and several air warming tubes, which valves and valve controls admitting or preventing air from passing through selected air cooling tubes; an air outlet from the cooling panel to an air inlet on the warming panel, one or a number of bundles of air warming tubes of suitable material, being graduated in length to impart different temperatures to the air passing through them; automatically or manually operated valve controls restricted to versions of the machine that include several air cooling tubes and several air warming tubes, admitting or preventing air from passing through selected air warming tubes; an air outlet to a clean air supply tube, which leads to a clean air outlet valve and a nozzle for a clean air flexible supply tube.

16. A refrigeration unit as in claims 1 to 15, provided with an easily portable and exchangeable metal liquid air supply flask of suitable shape, that when positioned on the refrigeration unit serves as a liquid air reservoir, that is provided with a high speed machine filling facility for rapid automatic filling in a central depot, being a spring loaded an\ stopper or similar device, and being provided with an air pressure outlet valve, and one or more wells that are sunk into the volume of the flask from the flask surface, so that the wells may house suitably positioned metal contact stubs that are positioned on the refrigeration unit, that insert into the wells when the flask is positioned onto the refrigeration unit, so that heat from the liquid air may pass through the metal walls of the flask to the metal contact stubs that are in contact with the walls of the flask, the outer surface of the flask being entirely covered with an insulating material that renders handling of the flask quite safe.

17. An air cooling jacket or clasp consisting of a defined quantity of metallic material for heat transfer, extending from the metal contact stubs that are inserted into their housing wells on the liquid air supply flask as detailed in Claim 16, to the cooling tubes, so that a required amount of heat may be transferred from the liquid air supply flask to the cooling tubes; the metal contact stubs having the form at their circular base of a number of converging semi-circular flanges of suitable length, that when not in operation are not in contact with each other throughout their length, that impart to the stud the form of a cone, and that converge by means of a resident spring facility to a central apex point under pressure of contact, which pressure they receive when they are inserted into their housing wells from a similar enclosing cone shape of the housing well, thus providing a close contact between these studs of the air cooling jacket or clasp and the liquid air supply bask, and thus permitting insertion;rrespectNe of the state of expansion or contraction of the metal contact stubs.

18 Versions of a refrigeration unit as in Claims 1 to 17, being provided with valves and valve controls, being either automatically or manually operated. The valves allowing or preventing air in the cooled air circulation system from passing through cooling tubes, and then through warming tubes, in order that required low air temperatures may be selected, and so that warm air temperatures may be selected, so that in case of viral attack, or in case of an epidemic, the clean air temperature may be lowered to a level sufficient to kill viruses, providing that low temperatures kill viruses, and so that this air may then be warmed to plus twenty degrees centigrade, for comfortable breathing and working; a simple mechanical valve being formed by the juxtaposition of two discs which cover the bundles of cooling tube ends and warming tube ends, one disc being fixed to the bundle of tubes, and the other revolving over the fixed disc by means of a central pin or spindle, extending to a revolving control button on the top of the refrigeration unit, holes being drilled or slots being formed through both discs, so that in one position the holes in both discs will coincide and allow air to pass through them, but the revolving disc being turned slightly, the holes are no longer coinciding, and air is prevented from passing; this -disc operation being automatic or manual, a simple arrangement for automatTc-;sc operation being the provision of a coiled spring of suitable expansion material over the disc valves, one end of the spring being fixed to the array -of tube ends, and the other end of the spring being fixed to the central pin or spindle that causes the revolving disc to turn, so that any particular air temperature will cause the spring coil to expand or to contract, thus turning the revolving disc through a distance of two or three millimetres to a required position relative to the fixed disc; the control button on the top of the refrigeration unit being pulled upwards slightly to disengage the manual control button from the central pin or spindle when automatic valve control is required, and the manual valve control having been selected, the chosen control button selections may be locked by the use of a locking stud or locking pin that blocks the control button; two valves may be placed one above the other, the upper valve control parts operating over the lower valve control parts, one central spindle being positioned within the other, in order to provide for the valve control of two temperature ranges; the two disc valve arrangement may be placed against compartment partitions, either horizontally or vertically, in order to allow or to prevent gas or air from passing through the valve, from one compartment to the next.

19. Versions of the refrigeration unit mainly as in Claims 1 to 17, but which rely for virus elimination not on low temperature, but on the use of the chemical filter, these versions being arranged to operate at a breathable air temperature of about twenty degrees centigrade, after the cooling of this air from the ambient air temperature to about twenty degrees centigrade, by the provision of one air cooling tube that is devoid of control valves and control means, being of a length of about forty centimetres for a version to be used in an ambient air temperature of about sixty degrees centigrade, and being of a length of about twenty five centimetres for a version to be used in an ambient air temperature of about forty five degrees centigrade, and being of a length of about fifteen centimetres for a thirty five degree centigrade temperature of the ambient air; these versions of the refrigeration unit being devoid of an air warming compartment, and being devoid of an air warming tube or tubes, an-d being devoid of air enclosing tubes,-and being devoid of an ambient air intake and outlet for warming cooled air; the air fitter, drawing indication No 2, Figure 2, being suitably placed on the air cooling pane! forming the tube box, drawing indication t9, Figure t; the air cooling tube, drawing indication 5, Figure t, being of variable length, extending from the air tract the liter, drang inctication 3, Figure 2, to the air inset to the protective clothing, drawing-indication 39, Figure 2, the lengths of the air CQotiOg tub in the version of the riat trait in rebtim to the estimate cooling rate of the air passing through the tube, of one degree per one centimetre length of cooling tube, and being in relation to the amount of heat that is arranged to be transferred from the source of heat to the cooling tube, by the cooling jacket or cociing contact, drawing indication 6, Figure 1.

20. A refrigeration unit substantially as described in Claims 1 to 19.

List of Drawing Indications.

1. Figure 2. Refrigeration unit air intake nozzle and on-off valve.

2. Figure 2 Refrigeration unit air filter.

3. Figure 2 Air duct from air filter to air cooling panel.

3. Figure 1 Air duct from air filter to air cooling panel.

4. Figure 1 Top ends of air cooling tubes, to receive air from air duct 3.

5. Figure t Air cooling tubes length 35 centimetres.

6. Figure t Metal cooling jacket or contact for transferring cold to air cooling tubes.

7. Figure t Liquid air metal reservoir.

8. Figure 1 Lower ends of air cooling tubes length 3S centimetres.

9. Figure 1 Air enclosing tube around air cooling tubes length 35 centimetres.

Figure 1 Air outlet from enclosing tube 9.

11 Figure 1 Air valve intake to air cooling tubes 12.

12 Figure 1 Air cooling tubes length 30 centimetres.

13 Figure 1 Valve control.

14 Figure 1 Air outlet from cooling panel 19 Figure 1 to air inlet 20 Figure 2.

Figure 1 Air valve on air cooling tubes 16 Figure 1, length 25 centimetres 1 6.Figure 1 Air cooling tubes length 25 centimetres.

1 7.Figure 1 Air valve on air cooling tubes 18.

1 8.Figure 1 Air cooling tubes length 20 centimetres.

1 9.Figure 1 Air cooling panel forming tube box.

20.Figure 2 Air inlet on warming panel from air outlet 14 on cooling panel 19.

2t.Figure 2 Air warming panel.

22.Figure t. Air outlet of enclosing tube 23 Figure t.

23 Figure 1. Air enclosing tube length 30 centimetres.

24.Figure 1 Valve control for air cooling tubes 16 Figure t.

25.Figure 1 Valve cortrol for air cooling tubes 18 Figure 1.

Z6.Figure 2 Lower ends of air warming tubes length 30 centimetres within enclosing tube 27,Figure 2.

27,Figure 2, Air warming compartment, 28.Figure 2 Open-closed air valve for air warming tubes 26 Figure 2.

29.Figure 2 Valve control for air valve 28 Figure 2.

Figure 2 Air compartment; 3t.Figure 2 Air inlet to air warming compartment 27 Figure 2, 32.Figure 2 Air outlet from air warming compartment 27 Figure 2.

33,Figure 2 Open-closed air valve for air warming tubes 34 Figure 2.

34.Figure 2 Valve control for valve 33 Figure 2.

35.Figure 2 Air warming tubes length 20 centimetres.

36.Figure 2 Valve for direct air outlet from air valve 28 Figure 2.

37,Figure 2 Air valve for operation of air warming tubes 35 Figure 2 length 20 centimetres, 38.Figure 2 Valve control for valve 37 Figure 2.

39.Figure 2 Air inlet to protection suit air supply tube 40 Figure 2.

40.Figure 2 Protection suit air supply tube.

41,Figure 2 Clean air outlet valve and flexible tube nozzle.

42.Figure 1 Used air intake nozzle and open-closed valve, 43,Figure 1 Ar cooling tubes within used air metal holding tube 44 Figure 1.

44.Figure t. Used air metal holding tube and cold contact with air cooling tubes 43 Figure 1.

45,Figure 1 Used air expulsion tube.

46.Figure 1 Open-closed air outlet valve and flexible tube air outlet nozzle.

47,Figure 1 Exchangeable liquid air supply flask.

48.Figure 1 Securing means for liquid air supply flask 47 Figure 1.

49.Figure 1 Supply tube within liquid air reservoir 7 Figure 1.

50.Figure 1 Spring held ball-and-socket valve within supply nozzle on supply flask 47 Figure 1