Hydrazine fueled diver&#39;s heating system
United States Patent 11 1 Bayles 1 Apr. 8, 1975 1 1 HYDRAZINE FUELED DIVERS HEATING 3.182.653 5/1965 Mauleds et a1. 126/204 SYSTEM 3.385.286 5/1968 Jones 126/204 3,556,205 1/1971 Harwood 126/204 5] In nt r: John J. Bayles. Oxnard. Calif. 3.583.386 6/1971 Slack 126/204 [73] Assignee: The United Suites of America as 31730.90) 5/1973 Armstrong et a1 60/218 l d b (h t flh 2 :3 w f g an, 0 8 Primary Examiner-William F. ODea I Assistant Examiner-Peter D. Ferguson 1 1 Flledi fl 1974 Attorney. Agent, or Firm-Richard S. Sciascia; Joseph M. St. Amand AB TRACT [52] US. Cl. 126/204; 60/218; 126/263; [57] S 128/|42; 128/19] R Apparatus for heatmg water used for the welfare of 511 161. c1. A6lf 7/06 divers cold Water environments wmprising a y 5 Fidd f Search 60/218 126/204, zine fuel canister, a means of pressurizing the fuel, a 123/142 191 R means of transferring heat from the fuel to a closed water system and a pump device for circulating water 5 References Cited through a closed circuit in the divers suit. Extra heat UNITED STATES PATENTS may be used in heating a C0 absorbent canister.  
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 EMF/ES owbqmI HYDRAZINE FUELED DIVERS HEATING SYSTEM BACKGROUND OF THE INVENTION This invention relates to a water heater and more particularly to an apparatus for heating a liquid such as water to be used for the welfare and comfort ofdiver/- swimmers in cold water environments.  
  For military and commercial purposes it is becoming increasingly desirable to place divers in hostile cold water environments below the ocean surface, sometimes at great depths. Hence the necessity to provide means for conserving the divers body heat to improve his efficiency and effectually preserve his life in extreme circumstance. Various means have been approached, with varying degrees of success. An attempt to solve the problem through use of an isotopic heating element has proved both impracticable and exorbitantly expensive. A method utilizing heat of crystallization is still in an early experimental stage. A more suc cessful method has heated water in a fuel fired water heater and the heated water pumped from the surface to the diver. Electrical grid resistance suits have been experimented with and a diver mounted electrical water heater has received some attention. Each of these last methods requires that the diver/swimmer be tethered by one or more umbilicals. Use of umbilicals presents a number of disadvantages including reduced efficiency of the systems and restriction of diver capability.  
  The present invention solves many of the above mentioned difficulties by providing a simple diver mounted apparatus which incorporates positive operation. Furthermore, this invention permits the diver/swimmer to be freed from any tether when the occasion arises. Desirable additional advantages are practicable when the invention is in use. By-products of the fuel decomposition may be used to drive the pump which circulates a warmed liquid such as water through the tubing of the diver&#39;s garment or protective suit and may be used to warm the carbon dioxide absorbent canister when the diver is on a semiclosed or closed circuit mixed gas breathing system. The warming of the canister improves the efficiency of the absorbent.  
 SUMMARY OF THE INVENTION The present apparatus for heating water or other suitable liquids for use in reducing the body heat losses of diver/swimmers in a cold water environment is simple, compact. serves more than one function and includes: a self-contained, self-pressurized fuel; a catalyst bed for decomposing the fuel exothermically; an insulated heat exchanger and a means for pumping heated water through a closed-circuit tubing divers dress.  
  Advantages over other diver heating systems are achieved in the present invention by providing an apparatus comprising a fuel canister; a means for pressurizing the fuel; a means for metering the fuel; a means for decomposing the fuel exothermically; a means for transferring the heat to a closed-circuit water system; a means for pumping the water through the closedcircuit; and exhausting the remaining heat over the CO absorbent canister for improving its efficiency. The heat exchanger component is also provided with means for conserving heat. In addition to use underwater, the present heating system has use in other environments. such as in outer space.  
 OBJECTS OF THE INVENTION It is an object of the invention to provide a water heating apparatus which is simply constructed, reliable and compact.  
  Another object of the invention is to provide a water heating apparatus which will provide a means by which a reduction of diver/swimmer body heat losses will be achieved and overcome.  
  A further object of the invention is to provide means for untethered excursion by divers in a cold water environment to extend the range of underwater activity.  
  Still another object of the invention is to improve the efficiency of the CO absorbent in a divers mixed gas breathing system.  
  Other objects, advantages and novel features of the invention will become apparent from the following description of the invention when considered in conjunc tion with the accompanying drawings wherein:  
 BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a diagrammatic view of one embodiment of the invention as worn by a diver.  
  FIG. 2 is a diagrammatic section view of the fuel container/heat exchanger of the present invention taken along line 22 of FIG. 1.  
  FIG. 3 is a diagrammatic view of another embodiment of the invention.  
 DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, wherein like reference numerals designate like parts, there is shown in FIG. 1 an embodiment of the present invention com prising a fuel container/heat exchanger 10, a divers tubing suit 12, a water pump 14 on the end of fuel container l0, and a jacketed CO absorbent canister I6 carried on the divers back along with the air tank I7 that supplies air to a divers helmet which is not shown. Water heated in fuel container 10 is circulated through suit 12 by means of a motor pump I4.  
  Tubing suit 12 is similar to the type used by astronauts. Heated water flows from the pump 14 to the suit via an outlet tube 18. Tubing in suit 12 normally has a manifold system, in the waist area, to distribute the heated water to several circuits throughout the suit. The water then returns to the fuel container/heat exchanger 10 via return tube 19.  
  FIG. 2 illustrates one embodiment of the fuel container/heat exchanger 10 where 20 is the fuel cavity enclosed by cylinder 22 and piston 24. The fuel cavity 20 is filled with hydrazine through a port 26 shown closed by plug 28. Fuel metering through orifice 30 is controlled by valve 32 which is operated by rotating con trol knob 34. The O-rings 36 and 38 on piston 24 seal the fuel chamber at the piston. Spring 40 acting under compression between cap 42 and piston 24 provides fuel pressurization above ambient pressure at any underwater depth because the chamber 44 containing spring 40 is open to ambient pressures through port 46.  
  Screws 48 secure cap 42 to the heat exchanger housing 50, by threading into drilled and tapped receivers 52. The heat exchanger housing 50 is screwed onto cylinder 22 at 53 to assemble and retain cylinder 54 and end plate 56 in compression. O-ring seal 58 ensures the integrity of the catalyst bed chamber 60 containing the catalyst 62 which decomposes the hydrazine fuel. Ce-  
 ramic pellets coated with Iridium, for example, are used as the catalyst. Depending upon the design of catalyst bed 60, the hydrazine will break down by exothermic reaction to form primarily Hydrogen, NH gas and some Nitrogen at around l,200F. As the hydrazine fuel from cavity 20 is metered at valve 32, by manipulation of control 34, through orifice 30 into catalyst bed 60, the resulting hot gases pass through multiple peripheral orifices 64 into the heat exchanger compartment 66 where heat exchanger coil 68 absorbs heat and transfers it to water, e.g., circulating through the coil from the inlet side 70 to the outlet side 72. O-ring seal 74 ensures the integrity of the heat exchanger compartment 66. Insulation 75, 76, 77 and 78 isolate heat exchanger coil 68 and catalyst bed 60, 62 and conserve the heat generated by the hydrazine fuel decomposition. Insulation 78 can be a split disc.  
  Exhausting gas is ported through 80 where it enters motor and pump 14. The hot gases operate a turbine motor. for example, which drives the pump. Motor and pump 14 forces the heated water from heat exchanger coil 68 through the tubing system of the divers suit. Heated water exits the heat exchanger at 72 passes through motor and pump 14 into the suit via a valved quick connect tube 18. The heated water is circulated through the tubing of the suit and then exits from the suit via another valved quick disconnect tube 19 for return to the heat exchanger 68. The water may be pumped as it exits or as it returns to the heat exchanger, as a matter of choice.  
  The exhausting gases which pass through and drive motor and pump 14 exit at vent 84 where the gases can pass via tubing 86 to the jacket about the CO absorbent canister 16 where the hot gases are used to heat the CO canister. Heating of the CO canister serves to improve the operation thereof since the absorbent in the canister absorbs more CO in the breathing system air supply 17 when warm than it does when cold. The gases are then vented away through valve 88. Valve 88, may otherwise be located at the exit 84 from the motor and pump. The CO absorbent typically is a combination of barium, calcium and potassium hydroxides.  
  As illustrated in FIG. 3, the heated water is pumped from heat exchanger 10 into the heat circulation system of the diver suit 90 via a valved quick disconnect tube 18, as in FIG. 1, and after circulating through the suit is returned via valved quick disconnect tube 19 to the heat exchanger. Where an air supply back pack is not used, gas exhaust tube 86 can be connected to the jacket about a C0 absorbent canister in a helmet 92 as shown in FIG. 3, and the gases vented away through a valve 94. As shown in FIG. 3, if desired, the diver air supply is provided to helmet 92 through an air supply line 96 from the surface. However, air to the helmet can be supplied from air tanks carried on the divers back, as in FIG. 1.  
  Where a tether line is provided to supply air from the surface, such as in FIG. 3, another source of energy, e.g.. electric, when desired, could be provided to power the motor and pump 14 rather than using the hot gases from the heat exchanger. However, the multiple use of the hot gases from the heat exchanger is an added advantage ofthis invention. In the present system. the hot gases, in addition to heating the water which in turn heats the diver suit, also drive the motor and pump. and heat the CO canister, thereby eliminating the need for an umbilical line to the surface for providing power to the motor and pump.  
  Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically claimed.  
 What is claimed is:  
  l. A self-contained, portable heating system for pro viding warmth to a wearer in a low temperature environment, comprising:  
 a. a body protective suit having a heat distributing means therein for distribution of heat throughout the suit;  
 b. a heat generating means connected to the heat dis tributing means of said protective suit for providing a portable heat source therefor;  
 0. heat transfer fluid operatively associated with said heat generating means and said heat distributing means;  
 d. pump means cooperating with said heat generating means and heat distributing means for pumping said heat transfer fluid through said heat generating means and throughout the heat distributing means of said protective suit;  
 e. said heat generating means comprising:  
 l. a fuel container containing hydrazine fuel,  
 2. a heat exchanger housing including a heat exchanger coil through which said heat transfer fluid is circulated,  
 3. an enclosed catalyst bed containing suitable catalyst material for exothermic decomposition of said hydrazine fuel connected between said fuel container and said heat exchanger housing,  
 4. a fuel metering means between said fuel container and said catalyst bed for controlling the flow of hydrazine fuel to said catalyst where it is converted by exothermic reaction into hot gases,  
 5. passageways between said catalyst bed and said heat exchanger housing whereby the hot gases generated are permitted to flow about said heat exchanger coil for heating the heat transfer fluid circulated therein f. means for exhausting expended hot gases from said heat generating means;  
 g. a breathing system including a C0 absorbent canister also carried by the wearer of said protective suit wherein hot gases exhausted from said heat generating means are used to heat the CO absorbent canister for more efficient operation thereof.  
  2. A system as in claim 1, wherein hot gases from said heat generating means are used to operate said pump means.  
  3. A heat generating means as in claim I wherein said catalyst material consists of iridium coated ceramic pellets.  
  4. A heat generating means as in claim I wherein said hot generated gases are at a temperature of about ],200F.  
  5. A heat generating means as in claim 1 wherein said heat exchanger and catalyst bed are insulated to conserve heat generated by said hydrazine fuel decomposition.  
  6. A heat generating means as in claim 1 wherein a pump means attached to said expended hot gas exhaust means operates to pump the heat transfer fluid through 6 said heat exchanger coil for circulation throughout said system following heating of said CO canister. heat distributing means. 8. A system as in claim I wherein said fuel metering 7. A system as in claim 1 wherein an exhaust port is means is an adjustable valved passageway. provided for venting said expended hot gases from the