Wearable Air Conditioners

The invention relates to cooling devices and in particular to a cooling system that can be incorporated into clothing, or applied directly to body surfaces. Existing air conditioning systems are designed to cool building spaces and can not be conveniently used to cool an individual who moves outdoors. One objective of the present invention is to provide a cooling system which is wearable and can contribute to the comfort of a person both indoors and out doors.

Another objective of the invention is provide a direct cooling of people and, thus, save the energy required for space cooling.

A third objective consists of increasing the safety of workers, such as fire fighters, who must work under life threatening high temperatures.

Another objective is to provide an improvement in medically prescribed cooling. For example, the invention can provide a direct cooling of patients with excessively high fever. The cooling system can likewise be used for casts and compresses. One of the side effect of casts, which enclose a body portion for long periods, is the fact that the casts act as insulators and reduce the natural heat loss from parts of the body enclosed by the casts. An objective of this invention is to incorporate a low cost temperature-adjustable cooling system in the cast, and thus reduce an excessive heat accumulation in the body portions enclosed by the cast.

Another medical objectives consists of the provision of cold compresses which can be temperature regulated. Existing cold compresses consist of ice packs. The temperature of the ice can not be changed and is too cold for prolonged application. The present invention provides compresses with any desired intermediate ice to body temperatures.

The invention consists of cooling systems that can be incorporated into clothing, or applied directly to portions of a human body which require cooling. The basic components of the invention are as follows. 1. A network of inter-communicating containers which are worn like a garment, and function as body heat removers. The heat remover containers contain water and an air vacuum to lower the boiling point of the water. The water boils at lower than ambient temperature and removes body heat. 2. A portable cold container to re-condense the vapor generated by the boiling water. 3. A cooling agent such as portable endothermic chemical reactants, or portable pre-frozen ice packs, to cool the condenser container. 4. A system of communications to obtain a continuous and spontaneous cooling water-vapor cycle. This communication consists of the follows. The condenser container is carried at a higher level than the water level in the heat remover container. A flexible tube communicates between the top portions of the heat remover and the condenser containers to conduct vapor generated in the heat remover to the condenser container. Another tube communicates between the bottom portions of the heat remover and the condenser containers to return, by force of gravity, the re-condensed water to the heat remover container.

The air vacuum in the heat remover container causes the water in the heat remover containers to boil at lower than ambient temperature. As the water boils it cools its surroundings and absorbs body heat. The vapor generated by the boiling water enters the cold condenser container and re-condenses into water by the relatively the cold temperatures in the condenser container. The water returns to the heat remover containers by force of gravity to continue the cooling water-vapor cycle of action. The rate of cooling is regulated by adjustment of the degree of opening of the communications between the heat-remover and the condenser containers.

Specialized adaptations of the invention include cooling insulated fire fighting clothing, cooling medical casts and bandages, and temperature regulated cold compresses.

FIG. 1 is a three dimensional front view of a wearable air conditioner.

FIG. 2 is a cross sectional view of an embodiment of a wearable air conditioner.

FIG. 1 and FIG. 2 illustrate the basic structures of an embodiment of a wearable air conditioner. As shown in the figures, there is present a series of vertical tubes 12, and horizontal tubes 13. The arrangement is that the all the vertical tubes tubes communicate with the top horizontal tube 13a, and the bottom horizontal tube 13b. All the horizontal tubes open into a side vertical tube 12a. The tubes 12-13 serve as heat remover tubes and as an evaporator chamber as will be described. The heat remover tubes have a very large surface volume ratio, are flexible, and shaped to fit body contour. For example, tubes 12-13 may consist of flexible intercommunicating nylon coils incorporated in, or attached to, the fabric of an undershirt 11. Extending from tubes 12-13 are flat heat conducting extensions 15. The extensions are cooled by tubes 12-13 and increase the area of the heat removing surfaces. The extension 15 may be made of a light weight heat conducting material such as a metal foil. Communicating with the top horizontal tube 13a is an outlet tube 16a. Communicating with bottom horizontal tube 13b is an inlet tube 16b. Also communicating with the top horizontal tube 13a is outlet and inlet tube 22. A valve 23 opens and closes tube 22. When open, the tube 22 forms a communication between tubes 12-13 and the outside environment. Present inside tubes 12-13 are an air vacuum and water 2w. The arrangement is such that water is introduced into tubes 12-13 through tube 22 after the air has been evacuated from the system, as will be described. The amount of water introduced into tubes 12-13 is such that the water level in the tubes 12 reaches about one half to two thirds of the height of the tubes. The water level thus defines a water phase 2w in the bottom portions of the tubes, and a vapor phase 2v in the top portions of the tubes.

Present at a higher level than the water level in tubes 12-13 is a container 17. As shown in the FIG. 2, the container is shaped, in part, like a dome. The arrangement is that the direction of the walls is always downward to ensure a gravity induced drainage of any liquid in the container. The container 17 serves as a cold condenser chamber, as will be described. The chamber is made of good heat conducting material such as aluminum.

The condenser container 17 is placed inside a container 25. The container 25 is made from good insulating material, such as plastic, to minimize warming of container 25 by environmental heat. The container 25 has top wall 26, side walls 27, and bottom wall 28. The arrangement is that top wall 26 is attached only to one of side wall 27 through flexible hinge means 29. This allows wall 26 to swing from a horizontal to a vertical position and to open and close container 25. The natural bias in the spring of hinge 29 is to keep wall 26 in its horizontal position and keep container 25 tightly closed. Extending from bottom wall of container 25 are extensions 30. The extensions are designed to form a support for condenser chamber 17, and to immobilize the condenser chamber in a permanent position in container 25. To that end the condenser chamber 17 is permanently attached to extensions 30. Inlet tube 18a opens into the top portion of condenser chamber 17. Outlet tube 18b opens into the bottom portion of condenser chamber 17. The tubes 18a and 18b open into the outside of condenser chamber 17 and the outside of container 25. To that end the tube 18a exits container 25 through an opening 27a in an upper portion of side wall 27 of container 25. The tube 18a fits tightly in opening 27a to prevent any leakage through 21a. Sealing material (not shown) may be used to assure a leak-proof opening. Tube 18b exits container 25 through an opening 28a in bottom wall 28 of container 25. The tube 18b fits tightly in opening 28a to prevent any leakage through 28a. Sealing material (not shown) may be used to assure a leak-proof opening. Flexible tube 19a forms a communication between tubes 16a and 18a. Flexible tube 19b forms a communication between tubes 16b and 18b. Present on flexible tubing 19a is clamp 20a. Present on flexible tubing 19b is clamp 20b. Screw 21a regulates the width of the clamp 20a. Screw 21b regulates the width of the clamp 20b. The arrangement is that as the width of the clamps is narrowed they tighten around tubes 19a and 19b and reduce the diameter of the tubes. When the width of the clamps is widened the pressure upon the tubes is reduced and the natural flexibility of tube 19a and 19b causes the diameter of the tubes to widen and reach their natural size.

Present inside container 25 is a replaceable cooling agent. The cooling agent consists of a plastic bag 31, which contains 2 chemical components that produce a heat absorbing endothermic reaction when mixed. The chemicals are separated when not in use. For example, bag 31 may contain ammonium nitrate granules 31a, and a bag 31b containing containing water 31c. The arrangement is that the walls of bag 31 are stronger than the wall of the bag 31a. When a cooling effect is desired pressure is transmitted to bag 31b through the walls of bag 31. This causes bag 31b to tear and to release the water into bag 31. This would allow the water 31c to to mix with the ammonium nitrate granules in bag 31 and to initiate the heat absorbing reactions. Present in container 25 is water 32. The water immerses bag 31 and condenser chamber 17. This facilitates the transfer of heat from condenser chamber 17 to bag 31. This serves to keep the condenser chamber 17 cold, as will be described. Container 25 is placed in a back pack 33. The pack 33 is carried, at a higher level than tubes the water level in 12-13, through straps 33a on the back of the person wearing the cooling system.

The operation of the device by the person wearing the device is as follows. To initiate cooling activity top wall 26 is opened and bag 31 is removed from container 25. Pressure is then exerted on bag 31 to tear the walls of bag 31b. This initiates the endothermic heat absorbing reactions in bag 31. The bag 31 is then put back in container 25. The top wall 26 is then closed. The user then wears the garment and carries the container 25 on the back with back pack 33. Clamps 20a and 20b are in their open positions to open tubes 19a and 19b. The fact that pack 33 with condenser 17 is carried at a higher level than tubes 12-13 would cause any liquid which may be present in condenser chamber 17 to drain into tubes 12-13. The vacuum in tubes 12-13 in the system causes the water 2w to boil at relatively low temperatures. The vapor which is generated in the evaporator tubes 12-13 enters the vapor phase 2v in tubes 12-13 and condenser container 17. The cold pack 31 in container 25 causes the temperature in condenser chamber 17 to be lower than the temperature in the evaporator tubes 12-13. The vapor pressure of the vapor which has entered container 17 from the evaporator tubes 12-13 can not be maintained in the relatively cold condenser chamber, and the part of the vapor in container 17 will re-condense into water. This causes the water vapor pressure in the condenser chamber 17 to be lower than the vapor pressure in the evaporator tubes 12-13. This vapor pressure differential causes additional vapor in tubes 12-13 to enter condenser chamber 17. More vapor will then be generated in tubes 12-13 to replace the vapor which has re-condensed in container 17. Thus, the water in tubes 12-13 will boil continuously as long as the the temperature in container 17 is lower than that of tubes 12-13. The condensed water returns spontaneously to the heat remover tubes 12-13 through tube 19b by the force of gravity.

The boiling of water 2w in the evaporator tubes 12-13 cools the water in the tubes to the water's relatively low boiling temperature. The cold water absorbs heat from tubes 12-13. The relatively cold tubes then remove heat from extensions 15 and garment 11. The cool garment will then remove heat from the person wearing the garment.

It is understood that that the cooling agent may consist not only of endothermic chemical bags but of any portable means that cause a cooling effect. For example, the cooling agents may consist of replaceable and renewable ice packs. The ice-packs will be renewed by insertion into standard freezers.

The wearable air conditioner may be used not only for comfort, but may be adapted for for use for a variety of specialized purposes. For example, the device may be incorporated into insulated clothing of fire fighters to extend the fire fighters' range of operation.

The device may likewise be adapted for use for medical devices which are applied to the body for cooling purposes. For example, the heat remover tubes 12-13 may be incorporated into pads which can be used as cold compresses. The temperature of the pads may be adjusted, according to the individual need of the patient, by clamp 20. Alternatively, tubes 12-13 may be adapted to be applied directly to areas of the body required cooling.

The heat remover coils may be incorporated not only in compresses but also in casts to help remove heat from the areas of the body insulated by the cast. The casts may be prepared as follows: Materials use to prepare the cast, such as Plaster of Paris is mixed with water to obtain a wet cement. The cement is then layered on the bandage enclosing the body portion requiring the cast. Tubes 12-13 are then placed on the layer of the cement on the bandage. Additional wet cement is then applied to the bandage to complete the cast and to cover tubes 12-13. Thus, tubes 12-13 will be placed inside the cast, between the cement layers during cast preparation. When the Plaster of Paris hardens tubes 11-14 will be fixed inside the cast.

It is understood that the above specialized applications of the wearable cooler are given as examples, and other adaptations may be made without departing from the essence of the invention as described in the claims.

The air vacuum in the wearable air conditioners may be induced, before water is introduced into tubes 12-13, as follows. It is understood that other methods of inducing a vacuum may be used without departing from the essence of the invention. Clamps 20a and 20b and valve 23 are put in their open position. Tube 22 is then connected to a vacuum pump (not shown), and air is evacuated from the evaporator and condenser systems. Valve 23 is then closed and tube 22 is disconnected from the vacuum pump. Tube 22 is then connected to a water source (not shown). Water is then introduced into tube 22 while valve 23 is closed, and trapped air is eliminated from tube 22. Valve 23 is then opened and water 24 is introduced into tubes 12-13. The amount of water is such that it fills 1/3 to 1/2 of the tubes 12-13. Valve 23 is then closed and tube 22 is disconnected from the water source.