Patent Grant
7513251
Emergency breathing apparatuses that provide oxygen to the user are known. Some provide oxygen directly, such as those that employ compressed or liquid oxygen. Others provide oxygen through a chemical reaction.
Conventional chemical oxygen generators may contain alkali metal chlorate candles, which are burned to produce oxygen. Other conventional chemical oxygen generators may contain potassium super oxide, which reacts with carbon dioxide to produce oxygen. Conventional chemical oxygen generators are generally used by miners, firefighters, military personal and the like to provide emergency oxygen when needed.
For example, U.S. Pat. No. 5,690,099 to Abramov et al. discloses a closed-circuit breathing system that includes a mask and a canister containing, for example, KO2. The canister contains one or more working compounds formed of a peroxide and/or superoxide of one or more metals of the alkali and alkaline-earth metal groups such as KO2 and CaO2 and a moisture releasing material such as wetted activated charcoal is utilized to replenish the oxygen and absorb the carbon dioxide in exhaled air. The canister includes an inlet port for receiving exhaled air, and an outlet port for providing breathable air for inhalation. The patent describes that the canister can be used in a closed or semi-closed circuit breathing system worn by a user such as a fireman, miner etc.
U.S. Pat. No. 3,938,512 to Mausteller et al. discloses an emergency breathing apparatus that includes a mask having breathing opening, directly in front of the outer end of which there is a chemical cartridge that is secured to the mask. The cartridge has an exhalation passage extending through it from front to back, with its rear end registering with the breathing opening. A check valve in the inhalation passage allows air flow only into the mask. In the exhalation passage there is a carbon dioxide removing and oxygen generating chemical. A breathing bag is supported by the cartridge and communicates with the front end of the exhalation passage. The mask is provided with an inhalation check valve allowing air being inhaled from the bag to bypass the chemical.
U.S. Pat. No. 5,267,558 to Haertle et al. discloses a chemical cartridge for respirators, the cartridge containing a chemical, e.g., potassium hyperoxide, which when acted upon by carbon dioxide and moisture, produces oxygen from a stream of inhaled air. Two discharge nozzles are provided, which project into the chemical and out of which the regenerated exhaled air flows. The incoming flow occurs over a large area and the outflow occurs over a small area with the peripheral surfaces of the discharge nozzles being spaced substantially equidistant from an inlet surface of the chemical, thereby ensuring optimum use of the chemical for oxygen production purposes because a user's exhaled air is caused to flow completely through the entire space occupied by the chemical.
U.S. Pat. No. 3,942,524 to Li et al. discloses an emergency breathing apparatus that includes a canister containing layers of KO2 particles separated by parallel screen assemblies, the upper two screen assemblies being connected by a vertical bypass screen near the canister inlet. The layered KO2 bed is effective to remove CO2 from exhaled breath, and generate oxygen for recharging the air prior to inhalation. The canister inlet is connected by a flexible hose to the exhalation side of a breather mouthpiece, the inhalation side of the mouthpiece being connected to the upper end of the inhalation chimney. Communication between the canister outlet and the lower end of the inhalation chimney is provided by a breather bag, fitted with a set of baffles to define a tortuous flow path for cooling the processed air. A collector mounted at the canister outlet prevents liquid KO2 (which forms KOH) from entering the breather bag. To protect the user and confine the heat within the canister, the canister is insulated.
U.S. Pat. No. 3,860,396 to Finley discloses a light-weight, portable oxygen generator containing an alkali metal chlorate candle. The generator includes a generally tubular housing, preferably formed of extruded aluminum or other heat-conducting metal, and preferably includes longitudinally-extending ribs which serve to dissipate heat generated inside of the housing. The generator also includes a dispensing valve through which oxygen passes.
U.S. Pat. No. 5,620,664 to Palmer discloses a light-weight, personal, portable oxygen dispenser that includes a cylindrical body. The cylindrical body is a light-weight material, such as extrudable aluminum, with a fluted or ridged exterior configuration to minimize heat conductivity to the fingers of someone holding the dispenser while it is operating.
U.S. Pat. No. 4,325,364 to Evans discloses a training breathing apparatus that includes a disposable canister filled with a reagent that creates heat by reacting with the moisture in exhaled breath.
Despite these various designs, conventional portable oxygen generators pose substantial drawbacks that either limit their use, or limit their use by a wide range of individuals that otherwise could benefit from their use. For example, professionals that are used to using such portable oxygen generators are constrained by the weight, material quality, construction, or heat generation of such devices. Likewise, these issues of weight, quality, construction, and heat generation also tend to prohibit such oxygen generators from being used by non-professionals, such as athletes or the like. Moreover, many of the conventional oxygen generators cannot be transported on commercial aircraft due to potential safety problems and leakage from cabin air pressure. The present disclosure thus seeks to overcome these disadvantages of the prior art, and provide improved portable oxygen generators.
For example, conventional potassium super oxide oxygen generators are generally bulky and must be worn in a harness. Furthermore, the chamber in which the active ingredient is held is usually made from heavy, high grade stainless steel. For example, conventional potassium super oxide oxygen generators can weigh between 4.5-7.5 kg.
Applicant has identified a need for potassium super oxide oxygen apparatuses in which the oxygen reaction is slowed down to decrease heat generation, thereby allowing the apparatus to be hand-held. Such hand-held generators may be used, for example, by people escaping fires, by skiers, by mountain climbers, by asthmatics, by people with emphysema, by people suffering from altitude sickness, and by athletes. Such hand-held generators may be also used as backup oxygen generators for Emergency Medical Service (EMS) squads, fire departments, miners, and the like, should their regular emergency oxygen become depleted.
Various embodiments will be described in detail, with reference to the following figures, wherein:
The disclosure is directed to a portable, light-weight, hand-held oxygen generating and breathing apparatus. As one breathes into the apparatus, the carbon dioxide and moisture from the breath react with the potassium super oxide, thus liberating heat and warm dry oxygen. As illustrated in
In embodiments, the container may be made of aluminum or other light-weight metal. For example, other suitable metals that may be used to form the container include aluminum alloys, tin, steel (such as stainless steel and carbon steel), and the like. While aluminum is preferred in terms of its light weight, such other metals may be used depending upon the size of the container and its intended use. For example, where the container is expected to be relatively small, the selection of a specific metal may be less important because the weight of the metal becomes less of a concern. In various other embodiments, the container may be made of ceramics, fiber glass, tempered (shatter-proof) glass, and TEFLON®.
In embodiments, the interior of the container is preferably coated so that the active ingredients inside of the container do not react with the container. For example, various chemical-resistant coatings are known in the art, and can readily be incorporated into a protective coating layer primarily for the inside of the container. Such suitable chemical-resistant coatings include, but are not limited to, halogenated materials such as HALAR® ethylene-chlorotrifluoroethylene copolymer (ECTFE) (Allied Chemical Corporation, Morristown, N.J.), TEFZEL® ethylene-tetrafluoroethylene (ETFE) (E.I. duPont de Nemours and Co. Wilmington, Del.), tetrafluoroethylene (TFE), TEFLON® polytetrafluoroethylene (PTFE), polytetrafluoroethylene fluorinated ethylene propylene (PTFE-FEP), polytetrafluoroethylene perfluoroalkoxy (PTFE-PFA), polyvinylidene fluoride (PVDF), polyethylene, polypropylene, and the like. In embodiments, TEFLON® (polytetrafluoroethylene or PTFE) is particularly preferred, in terms of its chemical properties and ready commercial availability.
In embodiments, the container may be jacketed with an insulating and/or heat-dissipating jacket. The insulating jacket may be made of, for example, silicone rubber or other insulating material. The insulating jacket may be ribbed on the inside surface, on the outside surface, or on both of the inside and the outside surfaces. Such ribs may be helpful, for example, in further insulating the user from heat generated inside the container, by providing a decreased surface area for heat to transfer from the container wall, to the insulating jacket, and thereafter to the user. Alternatively, or in addition, the container can include a heat-dissipating jacket to remove some of the heat generated within the container but while not transferring that heat to the user. The container may optionally include a connector for more convenient use. For example, the container can include a lanyard or strap to enable the apparatus to be worn around the neck of a user; a clip to enable the apparatus to be clipped to a belt, utility strap, or the like; a hook-and-loop connector to enable the apparatus to be attached to a mating hook-and-loop connector; or the like. Two or more connectors can be included, for example to provide alternative connection options. In embodiments, the container is preferably disposable and replaceable. However, in embodiments, the apparatus can be re-usable to minimize waste.
The term “potassium super oxide” encompasses a mixture of potassium monoxide (K2O), potassium peroxide (K2O2), and superoxide (KO2), where superoxide represents about 90% to about 95% of the potassium super oxide. In embodiments, the container contains the potassium super oxide in the form of, for example, a pellet(s), a granule(s) or a laminated sheet(s). In embodiments, the amount of potassium super oxide may range from about 100 g to about 200 g. In order to accommodate the potassium super oxide, the container may be of sufficient size to contain 6-10 ounces. Of course, it will be understood that lesser amounts of potassium super oxide can be used for smaller or shorter-use containers, such as amounts ranging from about 50 g to about 100 g, and that greater amounts of potassium super oxide can be used for larger or longer-use containers, such as amounts ranging from about 200 g to about 500 g or more. However, the container should be of a size limited to containing 16 ounces or less. Containers of a size to contain more than 16 ounces are no longer hand-held units, and would require that the user clip the apparatus to a belt or hang the apparatus around the neck using a neck strap.
In various embodiments, the container may contain graphite or carbon to help regulate moisture absorption and reduce the exotherm. The graphite or carbon may be in the form of, for example, graphite or carbon fiber fabric(s). For example,
In various embodiments, graphite or carbon fiber fabric(s) may be layered between every 25 mm to 75 mm of potassium super oxide, present as a pellet(s), a granule(s) or a laminated sheet(s). In various other embodiments, the potassium super oxide may be present in the form of sheets, and the graphite or carbon fiber fabric(s) may be placed on the bottom and around the inside of the cylinder.
In embodiments, the container may contain one or more catalysts, adjuvants, and/or initiators. The catalysts may be, for example, one or more of NaO2, Na2O, Na2O2, Ca2O2, Ba2O2, Li2O2, oxides of rubidium, and oxides of cesium. In embodiments, the catalyst is preferably selected from NaO2 and Na2O2. The catalyst may serve to reduce the amount of heat produced by the oxygen-generating reaction, and further may slow down the reaction time. The initiator may be, for example, one or more of copper oxychloride, CuCl2, and CuCl. In various embodiments, the amount of initiator present in the container is about 0.5% to 1.0% of the total weight of chemical compounds in the container. In various embodiments, the amount of the one or more catalysts, adjuvants, and/or initiators present in the container is about 5% to 10% of the total weight of chemical compounds in the container. In various embodiments, the ratio of the amount of the one or more catalysts, adjuvants, and/or initiators to the amount of potassium super oxide is about 10:90.
In embodiments, the container may contain a stainless steel tube containing sodium- potassium eutectic alloy in liquid form (NaK), which absorbs heat generated during the reaction. The stainless steel tube may be present as a straight tube, such as the stainless steel tube (5) in
In embodiments, the apparatus includes one or more valves, which generally help to regulate air and/or oxygen flow. For example, the apparatus may include at least one valve, located in the flow path between the mask and the container, to regulate air and/or oxygen flow. Although not limited to any particular valve design, a master turn-type valve (such as a knob) is preferred in embodiments, in view of its ease of use. Other valve designs can also be used, such as sliding valves, pressure valves, lever valves, combinations of intake, output, and check valves, and the like. In one particular embodiment, the valve includes a polymeric knob that can be easily turned on and off as needed to regulate the flow of air and/or oxygen. In embodiments, such a valve type is preferred because this valve type is easy for a user to operate, and the polymeric construction of the knob helps to reduce heat transfer from the container to the knob.
In embodiments, the apparatus may include a mask or mouth piece. In embodiments, the mask may be designed to fit snugly over the nose and the mouth of the person wearing the mask, such as the mask (11) illustrated in
In embodiments, the potassium super oxide oxygen generating apparatus weighs between about 250 g and 750 g, and may generate about 10-20 minutes of emergency oxygen, depending on the amount of super oxide present in the container and the amount of exertion by the user. In various embodiments, an oxygen-generating reaction can generate up to 100-120 degrees. In various embodiments, the apparatus may include an NaK alloy tube and a bellows or bag with a relief valve, which in combination can cool breathable air to about 30° C. to about 30° C., or to less than 30° C.
The above-described oxygen generating apparatus offers many benefits over conventional pressurized oxygen generators. For example, the components used in the above-described oxygen generating apparatus are non-hazardous and leak-proof, containing no compressed gas, opening the possibility for use as an emergency breathing apparatus on commercial airplanes. Furthermore, for example, the light-weight components and the slowed heat generation of the above-described oxygen generating apparatus allows it to be used for various hand-held uses. In particular, the above-described oxygen generating apparatus may be useful as an emergency breathing apparatus for escaping fires, as an oxygen supplement for athletes (including skiers and mountain climbers), and as a treatment for various health conditions (including asthma, emphysema, and altitude sickness). Still further, for example, the above-described oxygen generating apparatus offers the advantage of being light-weight, disposable, and replaceable.
While this invention has been described in conjunction with the embodiments set forth above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the embodiments of the invention set forth above are intended to be illustrative and not limiting. Various changes may be made without departing from the spirit and the scope of the disclosure as defined in the following claims.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3202150 | Miller | Aug 1965 | A |
| 3702110 | Hoffman et al. | Nov 1972 | A |
| 3860396 | Finley | Jan 1975 | A |
| 3938512 | Mausteller et al. | Feb 1976 | A |
| 3942524 | Li et al. | Mar 1976 | A |
| 4265238 | Swiatosz et al. | May 1981 | A |
| 4325364 | Evans | Apr 1982 | A |
| 5267558 | Haertle et al. | Dec 1993 | A |
| 5620664 | Palmer | Apr 1997 | A |
| 5690099 | Abramov et al. | Nov 1997 | A |
| 6957651 | Nuckols et al. | Oct 2005 | B2 |
| Number | Date | Country | |
|---|---|---|---|
| 20060280658 A1 | Dec 2006 | US |
