The present specification generally relates to face masks and more particularly, to face masks for regulating heat and humidity and enabling voice communication thorough a passive speaking membrane, a porous heat exchanger and a heat and moisture exchanger.
Inhaling cold air into the respiratory tract can be detrimental to the health of persons suffering from emphysema, asthma, angina and various other ailments. In cold weather, persons suffering from such ailments must either avoid breathing cold air altogether or take precautions to precondition (heat up and humidify) cold air before it is breathed. In addition, persons of good health working and exercising in frigid climates must take precautions against excessive heat and water loss due to the inhalation of frigid and low humidity air.
Persons who work in cold environments need to take precautions to avoid cold fatigue and lung spasms when being in a cold environment for a long duration. Lung spasms occur when the body is unable to naturally regulate the inhaled air to approximately 98.6 degrees Fahrenheit and 100 percent humidity. The transition point between properly regulated air at approximately 98.6 degrees Fahrenheit and 100 percent humidity and incoming air is called the isothermic saturation boundary. When cold low humidified air is present at this boundary it lowers the isothermic saturation boundary towards the lungs and lung spasms can be triggered.
Many breathing masks have been developed for protecting humans from exposure to extreme weather, such as cold. Masks have also been developed to protect humans from a variety of particulate and gaseous matter. However, prior masks have been unsuccessful in supplying sufficiently heated and humidified air to persons having respiratory and heart ailments to enable them to move about and work normally outside in cold weather without experiencing discomfort and pain. Additionally, prior masks have been unsuccessful in supplying sufficiently heated and humidified air to persons who work in a cold environment for a long duration e.g. more than 4 hours with properly allotted breaks.
Typically, this discomfort and pain is experienced by persons having respiratory conditions such as asthma, bronchitis, chronic bronchitis, emphysema or coronary conditions such as angina pectoris, post myocardial infarction, congestive heart failure, coronary heart disease, post coronary bypass and the like. Usually, such persons experience sufficient pain and discomfort that they must cease exerting themselves and get into a warm environment and rest. Hence, their activity in cold weather must be severely curtailed and, in some instances, substantially eliminated.
A variety of apparatuses have been employed in the past to overcome the ill effects of breathing cold air. These range from simple scarfs to complex breathing masks and are employed to preheat cold air prior to inhalation. Most of these devices, however, either do not sufficiently preheat and humidify the cold surrounding air before breathing or are complex, cumbersome and prohibitively expensive. These mask apparatuses which attempt to regulate air are an inefficient application of heat exchangers, reservoirs, or phase change materials. In most of these devices, condensation from the user's breath builds up in the textile or plastic and rests on the user's face. This water gets cold or freezes and can cause damage to the user's face like frostbite. Existing masks with heating elements are in efficient and have been inconvenient to use under normal use conditions because large, poorly located, poorly implemented battery power supplies are either separate from the mask and require additional means for transport or are located within the mask breathing space where the battery is exposed to high moisture levels and where a user would be subjected to dangers from battery corrosion or battery fumes.
Another problem experienced with existing masks having heating elements is that a large amount of power is required to directly heat cold surrounding air. Existing masks also lack the capability to speak clearly thought the mask. Accordingly, a mask overcoming the aforementioned disadvantages is desirable.
In European patent number EP1629859A1 to Talbot, this patent teaches a device having a user sized adjustable aperture. This device purportedly is capable of altering the humidity and temperature thereby regulating efficiency of the mask. This allows the user to breathe warmer or colder air. This mask achieves this by varying the resistance of air to flow into and out of the mask thus trapping more or less user exhaled air within the mask. Only the air within the mask has a different temperature and humidity than the air outside of the mask. When the user inhales, only a portion of their breath will be regulated. After the regulated air within the mask is consumed, the user begins to breathe air from the outside of the mask. Inhaled air has about 20 percent oxygen and exhaled air is roughly 15 percent oxygen by mass. Thus, this mask operates by adding only a user size adjustable aperture between the inside and the outside of the mask. This has the effect of trapping more or less exhaled air within the mask. When inhaling, only the air volume inside of the mask is warm and humid. To have all of the inhaled air warm and humidified, the inside volume of the mask would have to be the full volume of a breath. Using this approach reduces the oxygen concentration and can harm the user.
The mask as described with regard to the embodiments herein is designed to both regulate temperature and humidity of breath taken by a user while wearing the mask. The regulation unit is designed to passively increase the temperature and humidity that the user intakes while breathing in and to capture heat and humidity in the user's breath while breathing out. The temperature regulation portion of the mask captures the heat and humidity of the user's breath while breathing out and applies it to the user's breath while breathing in. The temperature regulation unit includes a passageway in which air is directed through a material with a high thermal conductivity.
During operation of the mask by the user, water is condensed on the internal surfaces of the mask. The phase change of the humidity in the user's breath is used to condensate releases more energy into the highly thermal conductive material, as opposed to not condensing the humidity, resulting in higher temperature regulation efficiency and capture of water. The condensed water does not sit and collect in the bottom of the mask, but rather wicks up in the internal surfaces of the mask to increase surface area and evaporation. This increases the user's inhaled humidity. Adding a layer of open cell foam that the air passes through could also increase the user's inhaled humidity. This technique is used in the medical field with humidity moisture exchangers on tracheostomy tubes.
As described herein, the materials used to construct the mask have a high thermal conductivity as well as a high heat capacity or thermal capacity to more efficiently store and release heat quickly. A high surface area throughout promotes heat conduction and convection within the apparatus. The material with a high thermal conductivity, the passageway, and/or other components of the mask may have a surface treatment to keep the mask hygienic. Texturing, silver, or a variation of Quantum Ammonia can be used as a surface treatment. Surface treatment can be done through plating, spraying small particles, soaking, and/or spraying with an electrostatic sprayer.
The mask is also configured to regulate the humidity of the air inhaled by the user. In one embodiment, condensed air and water is pulled and spread across the surface of the mask increasing the surface area and evaporation rate. This condensation and water is pulled to the surface using a vertical and/or horizontal wicking porous matrix and leveraging the surface tension of water. A grained texture on the internal surface of the mask could also encourage condensation movement and placement on more vertical surfaces. Ridges positioned closely adjacent to each other also wick the water across the surface of the mask. In some embodiments, a piezoelectric humidifier or ultrasonic humidifier could be used to atomize the condensation. The re-vaporized water would then be taken into the body when the user breathes in.
These and additional features provided by the various embodiments described herein will be more fully understood in view of the following detailed description, in conjunction with the drawings.
The embodiments set forth in the drawings are illustrative and exemplary in nature and not intended to limit the subject matter defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:
Referring now to
Furthermore, a textile garment (as illustrated in
The mask 100 further includes a removeable cover 118 configured to cover the air channels or passageways 114. The cover is 118 is slightly folded or bent at its center 124. As seen in
Those skilled in the art should recognize that the masks 100, 200, and 400 as described herein, are used both for their temperature regulation and humidity regulation properties. To achieve temperature regulation, exhaled air warms and raises the temperature of a copper heat exchanger. Thereafter, inhaled air is warmed up by the heat exchanger. A copper mesh is silver plated to inhibit bacteria growth. To regulate humidity, the heat exchanger is used to condense exhaled humidity. The heat exchanger or duct portion does not become saturated in water, rather, the condensed water wicks across the inner surface 138 of mask which increases water surface area and encourages evaporation. The wicking is done by narrow grooves on the inside of the mask.
When a user exhales, some of the humidity in their breath will condense. This water or condensation could be considered a waste product and discharged from the mask; or alternatively left to pool up on the inside of the mask. A mask with narrow grooves on the inside surface can wick water from the inside bottom to inside walls of the mask. This spreads the water across a larger surface area operating to promote additional water evaporation. This additional water evaporation increases the humidity that the user breath provides, thus increasing the humidity recovery efficiency of the mask.
Now referring to
A copper mesh 131 is provided as a heat exchanger. This mesh could be in a multitude of channels. It should be understood that any material or other metal may be used if it meets the properties and characteristics desirable for hear exchange during breathing of the user. In the present embodiment, as disclosed, a copper mesh is utilized. In this embodiment, copper is desirable for its high thermal density and thermal conduction properties. Heat exchangers are devices that transfer heat in order to achieve desired heating or cooling. An important design aspect of heat exchanger technology is the selection of appropriate materials and geometry to conduct and transfer heat quickly and efficiently.
In the present embodiment, copper or other materials may be used to assist in warming the temperature of the air though the heat exchanger. In one embodiment, copper is used since copper has many desirable properties for thermally efficient and durable heat exchangers. First and foremost, copper is an excellent conductor of heat. This means that copper's high thermal conductivity allows heat to pass through it quickly. Other desirable properties of copper in heat exchangers include its corrosion resistance, biofouling resistance maximum allowable stress and internal pressure, creep rupture strength, fatigue strength, hardness, thermal expansion, and specific heat. Other additional desirable properties of copper in heat exchangers include its antimicrobial properties, tensile strength, yield strength, high melting point, alloyability, ease of fabrication, and ease of joining. The combination of these properties enable copper to be specified for heat exchangers in industrial facilities where heating, ventilation and air conditioning (HVAC) systems, vehicular coolers, radiators, and as heat sinks are used to cool computers, disk drives, televisions, computer monitors, and other electronic equipment. Copper is also incorporated into the bottoms of high-quality cookware because the metal conducts heat quickly and distributes it evenly. Non-copper heat exchangers are also available. Those skilled in the art will also recognize that alternative materials such as aluminum, carbon steel, stainless steel, nickel alloys, and titanium may also be used. Any of the above-described materials or configurations may be used without undue experimentation in various embodiments described herein to achieve the desired results.
Additionally, the copper alloy is utilized not only for its high properties as a heat exchanger, but also because of copper's high antimicrobial properties. As a background, elevated copper levels inside a cell causes oxidative stress and the generation of hydrogen peroxide. Under these conditions, copper participates in a chemical reaction causing oxidative damage to microorganisms and/or pathogens. It has been shown that excess copper causes a decline in the membrane integrity of microbes, leading to leakage of specific essential cell nutrients, such as potassium and glutamate. This leads to desiccation and subsequent death of the cells forming the microorganism.
Furthermore, while copper is needed for many protein functions, in an excess situation (as on a copper alloy surface), copper binds to proteins that do not require copper for their function. This “inappropriate” binding leads to loss-of-function of the protein, and/or breakdown of the protein into nonfunctional portions. Accordingly, copper also increases the overall antimicrobial properties of the mask. In some embodiments, the copper mesh may be silver plated to achieve antimicrobial properties. Alternatively, any other coating or surface may be used which has antimicrobial properties. An antimicrobial surface or coating contains an antimicrobial agent that inhibits the ability of microorganisms to grow on the surface of a material. The most common and most important use of antimicrobial coatings has been in the healthcare setting for sterilization of medical devices to prevent hospital associated infections.
The present specification utilizes these properties as applied to the present face mask. In this embodiment, the silver prevents bacteria to grow when in contact with the human body which allows for the transmission of infectious disease. Antimicrobial surfaces are functionalized in a variety of different processes. A coating may be applied to a surface that has a chemical compound which is toxic to microorganisms. Other surfaces may be functionalized by attaching a polymer, or polypeptide to its surface. In this embodiment, the copper mesh is silver plated for antimicrobial properties. Furthermore, in this embodiment, the copper mesh 131 is cut to aid in assembly. Specifically, the copper mesh is cut of one or more of the same profiles rather than filling each channel with mesh. Corrugated cellulose paper or a heat moisture exchanger (HME) foam could be used to additionally increase the humidity regulation of the face mask. A phase change material such as calcium chloride can also be used to additionally increase the humidity and temperature regulation of the face mask.
Referring now to
The mask 200 further includes a cover 218 configured to cover the air channels or passageways. The assembly of component 218 and 201 creates the channels in which air passes through. Within this channel, copper mesh could be placed at 230 between 208, (i.e., the inside wall of 201,) and the cover when the mask is assembled so the user's breath comes in contact with the copper mesh. The cover is configured to assist in the manufacturing and assembly process. The cover includes an outer surface 228 and side portions 226a and 226b and a bottom 224, incorporated for reference. The cover may include a plurality of apertures 222 to further assist and regulate airflow to the air channels on the body 201 of the mask 200.
The rear of the mask 200 includes a surface 232. The surface 232 is configured to also contour the shape of the user's face while the mask is in user. The mask 200 includes an inner surface 238 which may also include an antimicrobial surface coating (i.e., such as silver).
These methods of temperature and humidity regulation can be applied to other embodiments that may include the following: a) only regulating the air that passes through the user's nose; b) only regulating the air that passes through the user's mouth; or c) being installed into pre-existing or modular products. An example of this technology implementation is integrating it into a cartridge of similar design to the 3M filter cartridges. This would allow the user to wear a cartridge compliant mask and breathe warm comfortable air through the developed regulation technology.
A porous heat exchanger allows the voice of the user to pass through the mask more easily without being obstructed. By locating the porous heat exchanger at the front of the mask, in close proximity to the mouth of the user, their voice will be less muffled encouraging better communication with others.
Referring now to
Referring now to
The mask 400 further includes layers 414, 420, 422, and 424 to create multiple air channels or passageways. The stacking and assembly of these components creates the channels in which air passes through. Each of these layers are separate bodies that create the final structure of the mask. A multitude of layers are needed to assist in the manufacturing and assembly process. Those skilled in the art will recognize that a fewer or greater number of layers could also be used. The heat exchanging material 418 is positioned between layers 414 and 422. Material 418 can be sheets of perforated aluminum stacked on top of each other in order to fill the channels and capture and release enough thermal energy.
Layer 414 may include a plurality of apertures 432 to further assist and regulate airflow to the air channels on the layer 412 of the mask 400. Layer 424 may include a plurality of apertures 408 to further assist and regulate airflow to the air channels on the body 412 of the mask 400. A feature that this embodiment includes is a thermal override that could be manual or automatic. Layer 422 is able to slide within layer 424 and 414 vertically in line with the top and bottom of layer 412. The top of layer 422 could move from point 430 to point 428 and create a variable sized opening. This opening could be a singular opening or a multitude of openings. When a user breaths through the mask and the layer 422 is up, some of the air will pass through the opening and some will go through the heat regulating channels. This will reduce the humidity and temperature regulating efficiency and allow the user to breathe colder air. Having a plurality of channels inside of the face mask can direct the flow of air so interacts with heat exchangers, HME material, or passes straight through. By incorporating an adjustable aperture regulated by layer 422, a lesser proportion of air may interact with a heat exchanger or HME material as the open aperture has the least resistance to flow. This alters the flow of air through the channels inside of the face mask. Multiple adjustable apertures could be incorporated that directly alter the flow of air through the heat exchanger or HME material.
When the user exhales, air passes through apertures 432 and contacts the material 418. At this stage in the air regulating process, the material 418 is colder than the user's breath. The humidity in the user's breath might condense into water and flow into or outside of the mask. If the water goes into the mask, it might first flow to surface 434. Surface 434 or 436 might have a texture that leverages the surface tension of water to flow some of the condensed water from surface 434 to surface 436. This might increase the surface area of the water. The environment within body 412 might be warm and the previously condensed water might evaporate and re-humidify the air when the user breathes in. The mask 400 includes inner surfaces 434 and 436 which may also include an antimicrobial surface coating (i.e., such as silver) for inhibiting the growth of pathogens and/or microorganisms.
The presented embodiment could use screws 416 to couple the components together. An alternative could be using plastic snaps or adhesion between different featuring bodies. It is noted that the terms “substantially” and “about” may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.
The mask 400 has aperture(s) wherein the size of the plurality of aperture(s) that directs air from the outside of the mask to the inside (and from the inside of the mask to the outside) is adjustable. This could also be called a ventilation aperture. When the size is changed by the user, this controls the ratio of air that passes through the heat exchanger versus air that just passes through the mask ventilation aperture. Adjusting this ratio allows the mask to capture more or less heat and condensation. This increases or decrease the regulation efficiency of the mask.
The mask has two unique paths for air to flow. The first a user size adjustable ventilation aperture and the second is a heat and moisture exchanger. Humidity and Temperature regulation efficiency of the mask is achieved through varying the ratio of air that passes through the heat and moisture exchanger and the ventilation aperture through the mask.
Thus, only the air within the mask has a different temperature and humidity than the air outside the mask. By including a heat and moisture exchanger, the air regulation is not limited to the volume of regulated air within the mask, but by the heat and water captured from the previous exhaled breath by the heat and moisture exchanger.
While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the claimed subject matter.
Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. It is therefore intended that the appended claims cover all such changes and modifications that are within the scope of the claimed subject matter.
| Number | Date | Country | |
|---|---|---|---|
| 62659311 | Apr 2018 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16388259 | Apr 2019 | US |
| Child | 17692157 | US |