US3229681A

US3229681A - Warming suit

Info

Publication number: US3229681A
Application number: US133931A
Authority: US
Inventors: Martin E Gluckstein
Original assignee: Ethyl Corp
Current assignee: Ethyl Corp
Priority date: 1961-08-25
Filing date: 1961-08-25
Publication date: 1966-01-18
Anticipated expiration: 1983-01-18

Description

Jan. 18, 1966 M. E. GLUCKSTEIN WARMING SUIT 2 Sheets-Sheet 1 Filed Aug. 25, 1961 INVENTOR ATTORNEY Jan. 18, 1966 M. E. GLUCKSTEIN WARMING SUIT 2 Sheets-Sheet 2 Filed Aug. 25, 1961 INVENTOR ATTORNEY United States Patent 3,229,681 WARMING SUIT Martin E. Gluclrstein, Farmington, Mich, assignor to Ethyl Corporation, New York, N.Y., a corporation of Virginia Filed Aug. 25, 1961, Ser. No. 133,931 17 Claims. (Cl. 126204) This invention relates to a comfort suit. More particularly this invention relates to a novel suit by which the human wearer may be kept relatively warm in cold climates for long periods of time.

Various insulated suits have been proposed by which heavy insulation retains body heat and permits the wearer to endure in a relatively cold climate. While such suits have achieved some degree of success for short exposures, the amount of insulation required for long duration is very high resulting in a heavy, bulky, and awkward suit. In extremely cold climates, say 50 F., the amount of the required insulation may be so great so as to make such a suit not feasible for active personnel.

Suits incorporating internal heating by means of portable batteries have also been proposed. However, the weight of the batteries required and the low voltage which can be generated at extremely low temperatures are serious handicaps.

It is an object of this invention to provide a novel comfort suit which will enable the wearer to endure extremely cold climates for long periods of time. Another object is to provide a comfort suit of relatively light weight which permits the wearer a high degree of activity and maneuverability while exposed to extremely cold climates. Another object is to provide a comfort suit incorporating means to utilize the heat generated by a chemical reaction between the breath and at least one chemical.

Still another object is to provide a method of providing heat in a comfort suit to be worn in cold climates.

Broadly, the objects of this invention are accomplished by providing a comfort suit incorporating provisions for a chemical reaction between the exhaled breath and at least one chemical. Heat liberated by the reaction warms the body parts adjacent to the reaction site. Additionally, by utilizing the pressure of exhalation, the warm gaseous reaction products are distributed to the body extremities which are warmed by the sensible heat of the gases. Further, provisions are made so that the gaseous products are contacted with catalytic beds located at the extremities and other parts of the body. The catalyst promotes a reaction with the attendant release of additional heat at the reaction site.

In another aspect, this invention provides a method of providing heat in a comfort suit to be worn in cold climates which method comprises contacting exhalation with a chemical capable of reaction with exhaled breath and transmitting the liberated heat energy to various body locations. A preferred method comprises contacting exhalation with a metal hydride, especially sodium aluminum hydride, whereby heat and a gaseous product including hydrogen are liberated, distributing said gaseous product and hydrogen to various body locations, contacting said hydrogen with an oxidation catalyst whereby an oxidation reaction takes place with the liberation of heat and transmitting the liberated heat to various body parts.

More specifically, the objects of this invention are accomplished by providing a comfort suit comprising a helmet, a face mask attachable to said helmet and equipped with gas inlet means, an enclosed chamber containing a chemical capable of reaction with exhaled breath, said chamber communicating with said face mask whereby due to the pressure of exhalation, breath is Patented Jan. 18, 1966 caused to contact and react with said chemical within said chamber to generate heat and a gaseous product, a garment capable of being joined to said helmet, said garment containing distribution means in communication with said enclosed chamber whereby the gaseous products of said reaction are distributed to various body locations and subsequently discharged to the atmosphere.

A preferred embodiment comprises a helmet, a face mask attachable to said helmet and equipped with gas inlet means, an enclosed chamber containing a metallic hydride, said chamber communicating with said face mask whereby due to the pressure of exhalation, breath is caused to contact and react with said hydride within said chamber to liberate heat and a gaseous product including hydrogen, a garment capable of being joined to said helmet, said garment containing distribution means in communication with said enclosed chamber whereby the gaseous products including hydrogen are distributed to various body locations and subsequently discharged to the atmosphere, an oxidation catalyst attached to said garment in various locations whereby contacting said gaseous product including hydrogen with the catalyst results in an oxidation reaction with the attendant release of heat.

The objects and advantages of my invention will become apparent from the following description, in conjunction with the annexed drawing, in which preferred embodiments are disclosed.

FIGURE 1 is a diagrammatic view showing a preferred embodiment of a face mask in accordance with my invention.

FIGURE 2 is a diagrammatic representation of a Warming suit in accordance with my invention, wherein heat is generated by reaction of exhalation with a chemical, and wherein heated gases are conveyed to the extremities of the body of the wearer due to the pressure of exhalation.

FIGURE 3 is a diagrammatic view of a warming suit according to my invention wherein the heated gases formed as above are distributed to the extremities by means of tubular connecting lines and are there passed through or over catalytic beds wherein an oxidation reaction takes place to generate more heat.

In FIGURE 1, 1 is the face mask housing, 2 is a supporting shoulder, 3 is a one-way atmospheric air inlet valve, 4 is a canister, 5 is a one-way canister inlet valve, 6 and 7 are chemicals, 8 is a tubular connecting line, and 9 is a manually adjustable control valve. In FIG-

URE

2, 10 is the face mask, 11 is a helmet, 8 is a tubular connecting line, 12 is a garment, and 13 are perforations in the garment. In FIGURE 3, 14 are tubes and 15 are catalytic beds; 1, 8, 10, 11, 12, and 13 are the same as in FIGURE 2.

Referring to FIGURE 1, as the wearer breathes in, air enters the face mask through one-way atmospheric inlet valve 3 and is inhaled. Due to its own pressure, the exhaled breath enters canister 4 through canister inlet valve 5 and is contacted with one or more chemicals 6 and 7. A chemical reaction takes place between the chemical and at least one component of exhaled breath to release heat. Part of the liberated heat is used to warm the incoming air and the wearers face and head. The gaseous effiuent from the canister, composed of unreacted gases which have been warmed by passage through the reaction zone and any gaseous reaction products which will also be at higher temperatures, is then distributed through line 8 to provide heat to any desired body location. Manually adjustable control valve 9 is provided to enable the wearer to control the amount of exhaled breath entering canister 4. By opening control valve 9, the exhaled breath by-passes the reaction zone 3 thereby reducing the quantum of the reaction and the liberated heat.

Referring to FIGURE 2, the warmed gases exit from the canister into tubular connecting line 8 and are discharged beneath air-tight garment 12 in the chest region.

Due to the pressure of exhalation, the gases will travel to .the four extremities and there be discharged through perforations 13 to the atmosphere. The sensible heat content of the circulated gases is used to warm the various body parts.

In the embodiment portrayed in FIGURE 3, air enters the face mask and exhaled breath is contacted with a metal hydride in canister 4 in a similar manner as previously described. The products of the reaction are heat, hydrogen, hydroxides, and the unreacted constituents of exhaled breath. The gaseous reaction products are distributed to the extremities by means of tubular connecting

lines

8 and 14 and are passed through catalytic beds 15 where an oxidation reaction between hydrogen and oxygen takes place with the attendant release of heat. The resulting products are discharged to the atmosphere through perforations 13.

The present invention provides a comfort suit having many advantages over those proposed by the prior art. The products of exhalation are caused to enter into a chemical reaction to liberate heat and hydrogen, and the pressure of the exhalation is utilized as the driving force to distribute gaseous products. The hydrogen is contacted with a catalyst and is oxidized to yield additional heat. Thus, a positive heat source is provided rather than merely utilizing heavy insulation to retain normal body heat as suggested with some prior art comfort suits. Also, heavy batteries are not requiredless than one pound of certain chemicals being sufficient to satisfy daily requirements. Moreover, the heat energy generated by the reactions is directly utilized, thus prviding maximum efliciency. Other advantages are that the suit is of relatively simple design and has no moving parts. The exhaled gases, after reaction with a metal hydride, are essentially bone dry, thereby precluding water condensation in the distribution system. Part of the heat liberated by the chemical reaction can be utilized to heat the incoming atmospheric air thus permitting the wearer to inhale relatively warm air. The comfort suit is relatively light affording the wearer maximum flexibility and movement. Moreover, the suit is attitude insensitive and thus functional irrespective of the orientation of the wearer, be it horizontal or vertical.

Many variations in the construction of the comfort suit are possible within the scope of this invention. For example, the purpose of atmospheric air inlet valve 3 is to allow one-way flow of air from the atmosphere into the mask and to act as a seal when the air is exhaled. Any appropriate mechanism to achieve this purpose is applicable. One-way check valves such as flapper valves, ball valves, etc. are useable. Canister inlet valve is similar to valve 3 and any of the aforementioned oneway valves may be used. The function of canister 4 is to contain the chemical in a somewhat compact form and to be a reaction chamber. It may be constructed of any material which is not reactive with the contained chemical and the products of reaction. To optimize heat transfer to the incoming air, it is preferable that a material having a high thermal conductivity be used. To further facilitate the warming of incoming air, a fin design may be incorporated and/or the incoming atmospheric air may be bafiied around the canister to increase the heat transfer area. The canister may have compartments to contain several different chemicals. Although not necessary, it is preferable that the canister be mounted in the face mask and in a manner so as to be easily replaceable with a new canister. Similarly, a quick disconnect coupling should be utilized to connect line 8 with the canister. Although the canister has been shown as an integral part of the face mask, other locations such as the lower or upper chest area are possible. However, as will be hereinafter discussed, the reaction site must be located near enough to the wearers mouth so that the water vapor of the exhaled breath will not condense in the distribution system.

Line 8 may also be an integral portion of the helmet and the gaseous products may be discharged beneath the garment at the junction where the helmet and garment are joined. The helmet may terminate and be joined with the garment at the neck region or it may terminate at the shoulder region and there be joined with the garment.

The helmet and garment can be constructed of light, insulated material so as to minimize heat transfer from the body to the atmosphere and yet allow a maximum degree of flexibility. These units are preferably, but not necessarily, air tight. The garment may be one integral unit of the coverall type covering the four extremities, or gloves and boots may be used. The garment may also be two or more separate units which are joined at the waist or neck regions etc. In the latter cases, the units must be joined in a manner so as to minimize air leakage. The various units may be joined in a conventional manner such as incorporating a slide fastener with covering flaps to minimize gas and heat loss. The extremities of the garment have small perforations to discharge the gases to the atmosphere. The number and size of the perforations at each of the extremities are varied depending upon the location of the exit gases from line 8. For example, if the gas is discharged under the garment in the chest region, to facilitate uniform distribution, the perforations on the hand areas are smaller and/or less in number as compared to the perforations at the feet areas.

An air-tight inner garment may be used as an insulation between the body and the distributed warm gases. In this embodiment gas flow will be between the garment and the inner garment.

In the preferred embodiment portrayed in FIGURE 3, a tubular distribution system conveys the gas stream to the four extremities and optionally to other parts of the body. The gases are passed through catalytic beds located at each of the extremities and oxidation of a portion of the gases is promoted. Additional heat is released at the reaction site. The catalytic beds comprise tubular containers filled with catalyst and may be attached to the underside of the garment or the catalyst beds may comprise a pocket in the suit which contains the catalyst. Alternatively, a catalytic material may be impregnated on the suit proper over relatively large areas, thereby providing heat energy of lower intensity but having a wider distribution. The resulting gases including the water vapor formed by the oxidation reaction may be further distributed over the body, but preferably are discharged to the atmosphere at the reaction site.

A consideration of prime importance is that any water vapor in the system must be kept from condensing. Since temperatures at some points within the suit would be below 32 F., any condensed water vapor would form frost or ice. Condensation can be prevented by maintaining temperatures above the dew point of the gas stream or by eliminating the water content therefrom. Thus, if the chemical reaction contemplated for production of heat does not require water as an essential reactant, a drying agent such as KOH, NaOH, A1 0 MgO, CaO, CaCl etc. can be incorporated into the face mask. The dried gases are then fed to the canister to react with the chemical contained therein. Under these conditions, water condensation is precluded and the canister may be placed in other locations such as the upper or lower chest areas, etc.

In a preferred embodiment, water vapor is one of the essential constituents entering into the chemical reaction. To preclude water condensation, the temperature of the exhaled breath must be kept above its dew point and, therefore, the canister must be located relatively close to the mouth.

The same considerations are applicable to the gaseous products resulting from the chemical reaction. If water vapor is a product, a drying agent should be incorporated into the system to preclude condensation downstream from the reaction. In the preferred embodiment of this invention, a metallic hydride reacts with the water vapor content of the exhaled breath thereby producing an essentially bone dry gaseous product. Thus, additional or special water absorbing means are obviated.

One of the features of this invention is that exhaled breath is caused to react with at least one chemical so as to liberate heat and/or a gaseous product capable of being oxidized to liberate additional heat. The approximate composition of the exhaled breath is 15 percent oxygen, 4 percent carbon dioxide, 5 percent water, 75 percent nitrogen, and 1 percent argon and other constituents. Under resting conditions, approximately 500 cubic centimeters of air are inhaled .15 times per minute. Thus, a minimum of approximately 0.2 pound of oxygen, 0.08 pound of carbon dioxide, and 0.04 pound of water per hour are available to react with a chemical to produce heat and/or gaseous products. Of course, during periods of activity, greater amounts of these components are available.

The heat required to permit the human wearer to endure in cold climates varies over a wide range dependent to a major degree on the atmospheric temperature. Accordingly, a variety of chemicals may be utilized in the comfort suit of this invention to provide the heat required in any given environment. Broadly, any chemical capable of reaction with the oxygen, carbon dioxide, and Water constituents of the breath or any combination of these to yield heat and/ or a gas capable of being oxidized may be utilized. The chemical should preferably be a solid so as to minimize any possibility of leakage. It should be capable of entering into a reaction of moderate rate without any tendency toward explosiveness or pyrophoricity. The reaction should preferably yield gaseous or solid products and the products should be free from any toxic or noxious characteristics.

A class of chemicals possessing many of these properties are the alkali metals and the alkaline earth metals, the oxides, peroxides, and hydroxides of these metals. Of this group, the metals lithium, sodium, and calcium, oxides such as calcium oxide and barium oxide, peroxides such as sodium peroxide and barium peroxide and hydroxides such as potassium hydroxide, sodium hydroxide and calcium hydroxide are preferred. These materials react with one or more constituents of the breath at moderate rates and do not generate noxious products. These materials may be used singly or in combination.

Water vapor reacts with the above described metals to yield hydrogen, a hydroxide, and heat and reacts with the metal oxides to yield heat and the hydroxide. The hydroxides react with carbon dioxide to yield the carbonate and heat. The peroxides react with water vapor to yield oxygen, 9. hydroxide, and heat.

Another group of compounds useable to generate heat are metal alloys. These include alloys of metals such as lead, bismuth, antimony, tin, etc., with an alkali or alkaline earth metal. Typical examples are alloys of sodium and lead, bismuth and sodium, calcium and lead, etc. The particular com-position of the alloy may be formulated so as to obtain the desired rate of reaction, eliminate any possibility of a pyrophoric reaction, etc. The alloys react with water vapor to yield heat and hydrogen, and hydroxides.

Organic anhydrides can also be used. Compounds such as phthalic anhydride react with water vapor to yield the acid and heat. Additionally, a second compound, for example a metal oxide can be utilized to react with the acid in the presence of moisture to yield the salt and additional heat.

In many of the above enumerated reactions, the generated hydrogen together with oxygen which is generated by the reaction or contained in exhalation, may be circulatcd to various body locations and there contacted with an oxidation catalyst. The ensuing oxidation reaction liberates additional heat.

It has been estimated that about 200 B.t.u.s per hour, appropriately distributed to various body arts, are adequate to maintain human life under extremely cold conditions for long periods of time. Thus, in a preferred embodiment, the chemicals that can be used in this invention are those capable of reaction with any of the constituents of breath to liberate at least 200 B.t.u.s per hour, or those liberating a lower amount of heat plus a gaseous product which can be oxidized to liberate additional heat. In other words, the sum of the heat released during the original reaction and that liberated from oxidation of the gaseous product is preferably at least 200 B.t.u.s per hour.

The preferred chemicals useable in this invention are those which are capable of hydrolysis with the attendant release of heat and hydrogen. The gaseous product resulting from such a reaction will be essentially bone dry and water condensation problems are precluded. Broadly, any simple or complex hydride capable of reacting with Water vapor is useable as the chemical of this invention. The preferred hydrides include those of the alkali and alkaline earth metals including lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, etc. and bi-metallic hydrides including the alkali metal and alkaline earth metal hydrides of boron and aluminum such as lithium borohydride, sodium borohydride, potassium borohydride, calcium borohydride, lithium aluminum hydride, calcium aluminum hydride, sodium aluminum hydride, potassium aluminum hydride, etc. Of these, the alkali metal hydrides of aluminum in; cluding lithium aluminum hydride, sodium aluminum hydride and potassium aluminum hydride are preferred. These compounds show a very high degree of reactivity with water vapor and yield maximum amounts of hydrogen per pound of hydride. The most preferred compound is sodium aluminum hydride. This compound is stable, relatively easy to manufacture, and in large quantities is one of the most inexpensive compounds per pound of liberated hydrogen.

In the preferred embodiment, the exhaled breath is caused to contact sodium aluminum hydride contained in canister 4. A hydrolysis reaction takes place with a release of approximately 2630 B.t.u.s and 2-6 ft. (32 F., 1 atm.) of hydrogen per pound of hydride. Hydrogen is generated as a product according to the following overall reaction:

The sodium hydroxide and aluminum hydroxide are retained in the canister and hydrogen, in addition to the oxygen, carbon dioxide, and nitrogen portions of the entering gas stream, constitute the gaseous reaction products. No carbon monoxide in detectable amounts is produced by this reaction. Part of the liberated heat is used to warm the incoming air and the face and head. Catalytic beds are incorporated into the garment at each of the four extremities and if desired on the chest, back, and trunk areas of the body. By means of the tubular distribution system, the gaseous product including hydrogen is caused to contact the various catalytic beds. The hydrogen and oxygen portions of the gas stream enter into an oxidation reaction with the attendant release of about 300 B.t.u.s per cubic foot of hydrogen oxidized. The gaseous products including water from the oxidation reaction are discharged to the atmosphere.

With this preferred embodiment, one pound of the hydride fully reacted with the water Vapor of the exhaled breath provides about 2630 B.t.u.s as the heat of hydrolysis and 7800 B.t.u.s from the oxidation of the liberated hydrogen for a total of about 10,430 B.t.u.s. By adjustment of control valve 9, the quantity of water vapor available for reaction and thus the rate of hydrogen and heat liberation can be controlled and a moderate amount of heat can be supplied to the various body parts over a relatively long period of time. Under resting conditions, approximately 0.04 pound of water is exhaled per hour. This amount of water reacted with the hydride liberates about 80 B.t.u.s as the heat of hydrolysis and about 0.8 cubic foot of hydrogen which when oxidized releases approximately 240 B.t.u.s. Thus, under the least favorable conditions, an excess of 200 B.t.u.s per hour are available for distribution to various body parts. As the wearer performs any activity, greater amounts of exhaled water vapor are available adding to the quantum of the reaction with the attendant release of larger amounts of heat and hydrogen. For environments demanding an extremely large amount of heat, provisions can be made for introducing water from an external source or for utilizing other body fluids.

Any of the well known catalysts capable of promoting the oxidation of hydrogen may be used. These include catalysts with the active agent being a metal or metal oxide such as vanadium, copper, chromium, manganese, cobalt, nickel, palladium, platinum, etc. A highly eificient catalyst which is preferred for this reaction incorporates platinum as the active agent. Platinum catalysts are generally supported on carrier materials such as alumina, magnesia, silica gel, asbestos, metallic wires, diatomaceous earth, etc., and usually contain from about 0.01 to 3.0 percent of platinum. Methods of preparing such catalysts are well known to those skilled in the art.

The approximate stream compositions at various points throughout the system are as follows:

Point One Three The approximate temperature of the exhaled .breath is 35 C., the temperature of the gases in the face mask after reaction with sodium aluminum hydride is about 50 C., and the temperature of the gas stream after reaction with the platinum catalyst is approximately 100 C.

For the hydrogen gas concentrations contemplated by this invention, the oxidation reaction produces relatively moderate temperatures with no actual flames or glow being produced. The gaseous products from both the reaction in the canister and the oxidation reaction of the hydrogen are non-toxic. For most situations, the composition of the gaseous stream containing hydrogen is outside the limits of inflammability, thus providing for maximum safety. To maximize distribution of gaseous products, small pumps or fans driven by natural body movements such as chest expansion during breathing, arm and leg movements during walking, etc. may be used. I The comfort suit of this invention may also be used to provide heat to personnel exposed to a variety of environments. For example, the suit may be used to provide heat to underwater divers using portable selfcontained or stationary air sources. In such an application, the canister containing the metal hydride is incorporated into a water-tight face mask or helmet. Exhaled breath is used to react with the hydride and the warmed gases are circulatedbeneath a water-tight garment or through tubes to various body locations. Also, catalytic beds may be incorporated into the extremities or.other locations of the water-tight garment to permit the oxida tion of hydrogen .to yield additional heat. Alternatively, provisions may be made for reacting seawater with the hydride in an external hydrogen generating unit. The hydrogen together with the exhaled breath containing oxygen is then contacted with the catalytic bed. Rather than using exhaled oxygen, the hydrogen may be mixed with air from the divers air tank and passed to the catalytic bed appropriately located.

Methods for preparation of the chemicals used in this invention are well known to those skilled in the art. See for example, Inorganic Chemistry by R. B. Heslop and P. L. Robinson, Elsevier Publishing Company, New York, 1960; and Inorganic Chemistry by T. Moeller, John Wiley and Sons, Inc., New York, 1952,; and US. Patents 1,958,012; 2,567,972; and 2,920,935.

I claim:

1. In a suit adapted to be worn in cold climates and incorporating provisions to utilize a chemical reaction involving exhalation to provide heat and produce an oxidizable material, a garment, means for containing an oxidation catalyst attached to said garment, an oxidation catalyst positioned within said catalyst-containing means, and means to deliver said oxidizable material to said catalyst.

2. A method of providing heat in a suit adapted to be worn in cold climates which method comprises contacting exhalation with a metal hydride whereby a heated effiuent gas containing hydrogen and oxygen is liberated, distributing said effluent gas to various body locations, contacting said effiuent gas with an oxidation catalyst whereby an oxidation reaction takes place with the liberation of heat, and transmitting the liberated heat to various body parts.

3. A suit comprising a face mask equipped with breathing gas inlet means, an enclosed chamber containing a metal hydride capable of liberating hydrogen in the presence of moisture, means to convey exhalation from said face mask to said chamber, a garment, means to convey elfiuent gas from said chamber to said garment, and an oxidation catalyst attached to said garment and connected with said eflluent gas conveying means.

4. A suit comprising a helmet, a face mask adapted to be attached to said helmet and equipped with breathing gas inlet means, an enclosed chamber containing a metal hydride capable of liberating hydrogen in the presence of moisture, means to convey exhalation from said face mask to said chamber, a garment adapted to be joined to said helmet, means for conveying effluent gas from said chamber to said garment, means for containing an oxidation catalyst attached to said garment and connected to said effluent conveying means, and an oxidation catalyst positioned within said catalyst-containing means.

5. In a suit adapted to be worn in cold climates and incorporating provisions to utilize a chemical reaction to provide heat, a face mask equipped with breathing gas inlet means and exhalation outlet means, an enclosed chamber containing a metal hydride capable of liberating hydrogen in the presence of moisture, means for conveying exhalation from said exhalation outlet means to said chamber, a garment, means for containing an oxidation catalyst attached to said garment, means for conveying effluent gas from said chamber to said catalyst-containing means, and an oxidation catalyst positioned in said catalyst-com taining means.

6. A suit comprising a face mask equipped with breathing gas inlet means, an enclosed chamber containing sodium aluminum hydride, means for conveying exhalation from said face mask to said chamber, a garment, and means for conveying effluent gas from said chamber to said garment.

7. A suit comprising a face mask equipped with breathing gas inlet means, an enclosed chamber containing sodium aluminum hydride, means for conveying exhalation from said face mask to said chamber, a garment, means for conveying effluent gas from said chamber to said garment, and an oxidation catalyst attached to said garment and connected with said efliuent gas conveying means.

8. A suit comprising a helmet, a face mask adapted to be attached to said helmet and equipped with inlet gas heating means, an enclosed chamber containing sodium aluminum hydride, means for conveying exhalation from said face mask to said chamber, a garment adapted to be joined to said helmet, means for conveying eflluent gas from said chamber to said garment, means for containing an oxidation catalyst attached to said garment and connected to said efiiuent gas conveying means, and an oxidation catalyst positioned within said catalyst-containing means.

9. In a suit adapted to be worn in cold climates and incorporating provisions to utilize a chemical reaction to provide heat, a face mask comprising a face mask housing, breathing gas inlet means and an enclosed chamber attached to said housing, said chamber containing sodium aluminum hydride, said chamber being equipped with exhalation inlet means and effluent gas outlet means.

10. In a suit adapted to be worn in cold climates and incorporating provisions to utilize a chemical reaction to provide heat, a face mask equipped with breathing gas inlet means and exhalation outlet means, an enclosed chamber containing sodium aluminum hydride, means for conveying exhalation from said face mask to said chamber, a garment, means for containing an oxidation catalyst attached to said garment, means for conveying efliuent gas from said chamber to said catalyst-containing means, and an oxidation catalyst positioned in said catalyst-containing means.

11. A method of providing heat in a suit adapted to be worn in cold climates, which method comprises reacting exhalation with sodium aluminum hydride to form a heating efiiuent gas, and transmitting said efiiuent gas to vari ous body locations.

12. A method of providing heat in a suit adapted to be Worn in cold climates which method comprises reacting exhalation with sodium aluminum hydride whereby a heated eflluent gas containing hydrogen and oxygen is liberated, distributing said efiiuent gas to various body cations, contacting said efliuent gas With an oxidation catalyst whereby an oxidation reaction takes place with the liberation of heat and transmitting the liberated heat to various body parts.

13. A method of providing heat in a suit adapted to be Worn in cold climates which method comprises contacting exhalation with a chemical capable of reaction with exhaled breath, said chemical being selected from the group consisting of alkali metals, alkali metal hydrides, and alloys of alkali metals with metals selected from the group consisting of lead, bismuth, antimony, and tin, to form a heated effluent gas, contacting said eflluent gas with an oxidation catalyst whereby an oxidation reaction takes place with the liberation of heat, and transmitting the liberated heat to various body parts.

14. A suit comprising a face mask equipped with breathing gas inlet means, an enclosed chamber containing a chemical capable of reacting with exhalation to produce a heated effluent gas therefrom, said chemical being selected from the group consisting of alkali metals, alkali metal hydrides, and alloys of alkali metals with metals selected from the group consisting of lead, bismuth, antimony and tin, means to convey exhalation from said face mask to said chamber, a garment, means to convey said heated efiiuent gas from said chamber to said garment, means for containing an oxidation catalyst attached to said garment and connected to said efliuent gas conveying means, and an oxidation catalyst positioned within said catalyst-containing means.

15. In a suit adapted to be Worn in cold climates and incorporating provisions to utilize a chemical reaction to provide heat, a face mask comprising a face mask housing, breathing gas inlet means and an enclosed chamber attached to said housing, said chamber containing a chemical capable of reacting with exhalation to produce a heated efiiuent gas therefrom, said chemical being selected from the group consisting of alkali metals, alkali metal hydrides, and alloys of alkali metals With metals selected from the group consisting of lead, bismuth, antimony, and tin, said chamber being equipped with means to permit the entrance of said exhalation means to permit the exit of said heated efliuent gas, a garment, means for containing an oxidation catalyst attached to said garment, means for conveying efliuent gas from said chamber to said catalyst-containing means, and an oxidation catalyst positioned in said catalyst-containing means.

16. A suit comprising a face mask equipped with breathing gas inlet means, said inlet means providing communication between the interior of said mask and the external atmosphere, an enclosed chamber containing a chemical capable of reacting with exahalation to produce a heated efliuent gas therefrom, said chemical being selected from the group consisting of alkali metals, alkali metal hydrides, and alloys of alkali metals with metals selected from the group consisting of lead, bismuth, antimony, and tin, means to convey exhalation from said face mask to said chamber, a garment, means to convey said heated eifluent gas from said chamber to said garment, means for containing an oxidation catalyst attached to said garment and connected to said effluent gas-conveying means, and an oxidation catalyst positioned within said catalyst containing means.

17. In a suit adapted to be Worn in cold climates and incorporating provisions to utilize a chemical reaction to provide heat, a face mask comprising a face mask housing, breathing gas inlet means, said inlet means providing communication between the interior of said mask and the external atmosphere, and an enclosed chamber attached to said housing, said chamber containing a chemical capable of reacting with exhalation to produce a heated efiluent gas therefrom, said chemical being selected from the group consisting of alkali metals, alkali metal hydrides, and alloys of alkali metals with metals selected from the group consisting of lead, bismuth, antimony, and tin, said chamber being equipped with means to permit the entrance of said exahalation, means to permit the exit of said heated effiuent gas, a garment, means for containing an oxidation catalyst attached to said garment, means for conveying effiuent gas from said chamber to said catalyst-containing means, and an oxidation catalyst positioned in said catalyst-containing means.

References Cited by the Examiner UNITED STATES PATENTS 2,347,583 4/ 1944 Vartabedian 2-2.1 2,429,973 11/ 1947 Alexander 126204 2,551,142 5/ 1951 Lessard 126204 2,648,325 8/1953 Siple 126-204 2,889,210 6/ 1959 Borard 23-4 2,996,062 8/ 1961 Weiss 126208 3,148,034 9/1964 Bovard et al 23-4 FOREIGN PATENTS 812,348 2/1937 France.

1,182,262 1/1959 France.

FREDERICK L. MA'ITESON, IR., Primary Examiner.

DAVID J. WILLIAMOWSKY, THOMAS J. HICKEY,

JAMES W. WESTHAVER, Examiners.

Claims

1. IN A SUIT ADAPTED TO BE WORN IN COLD CLIMATES AND INCORPORATING PROVISIONS TO UTILIZE A CHEMICAL REACTION INVOLVING EXHALATION TO PROVIDE HEAT AND PRODUCE AN OXIDIZABLE MATERIAL, A GARMENT, MEANS FOR CONTAINING AN OXIDATION CATALYST ATTACHED TO SAID GARMENT, AN OXIDATION CATA-