Respiratory hood

Information

  • Patent Grant
  • 6834646
  • Patent Number
    6,834,646
  • Date Filed
    Wednesday, December 19, 2001
    23 years ago
  • Date Issued
    Tuesday, December 28, 2004
    20 years ago
  • CPC
  • US Classifications
    Field of Search
    • US
    • 128 20527
    • 128 20529
    • 128 20617
    • 128 20123
    • 128 20522
    • 128 20125
  • International Classifications
    • A62B1800
    • Term Extension
      104
Abstract
A positive-pressure respirator hood assembly comprising, a gas-impermeable hood made of a flexible material, formed with at least a transparent visor portion; a gas treatment unit, comprising a filter and a power-operated blower to force air through the filter and generate a positive pressure within the hood; a one-way purge valve for facilitating the exhaust of exhaled gases and moisture from the hood; and a sealing portion for sealingly securing the hood over a body portion of the user; the respirator hood assembly is designed to be compactly received in a container and to be deployed into an operative state automatically, whereby a user is provided protection from toxic gases and particulate material.
Description




FIELD OF THE INVENTION




This invention relates to emergency safety equipment, particularly respirator hoods that provide filtered air to persons in toxic environments.




BACKGROUND OF THE INVENTION




There is increasing interest both from governmental agencies and the general public in protecting individuals from the harmful effects of toxic materials in the event of accidental incidents such as chemical spills, escape of toxic and noxious gases, smoke filled areas, dust and fumes, and in the event of chemical, biological, or other terror events.




In addition, there is a strong desire among certain people to protect their pets and work animals (seeing-eye dogs, livestock, etc.) from the same harmful effects.




Immediate protection of the respiratory tracts, eyes, and skin is required in such incidents and many of these incidents occur with little or no warning. This requires that any equipment used to protect the individual or animal (hereinafter in the specification and claims referred to as “user”) be readily available, i.e. carried with the user or stored nearby, and readily deployable into an operative state.




Protective industrial masks, hoods, and powered air respirators are known, but they require skills and training in order to provide adequate protection. They are also bulky and not designed to be conveniently carried and rapidly deployed.




Often the user exposed to the toxic environment is untrained in safety procedures, such as how to don and activate a powered air respirator hood.




Most of the existing respiratory protective means are by necessity made in several sizes and do not fit both adults and children in one size.




In the event of a sudden or unexpected situation resulting in a toxic or noxious environment, it is clearly an advantage to have a device to supply filtered or purified air and also to provide nominal protection to the otherwise exposed skin of the head and neck from gases, liquids/droplets, particles, fine sprays and aerosols. Advantageously, the device should be readily available (easily carried and/or stored) and suitable for a wide size-range of users (adults, children, the elderly, the infirm, handicapped and sick people, people with beards, eyeglasses, long hair, etc., and animals) without a need to conform to facial features or body shapes. Furthermore, it is preferable that the activation and functioning is automatic, the donning is self-explanatory and comfortable, and the device is suitable for extended operation as well as short term use. It is also advantageous that the device has a long shelf life.




SUMMARY OF THE INVENTION




Accordingly, it is the objective of this invention to provide a device that is protects a user from toxic environments for quick escape or for an extended period of time, typically for up to several hours, that is collapsible, easily carried or stored, compact, lightweight, comfortable, easy to use, one-size-fits-all, whose donning is self-explanatory, whose activation is automatic, and requires no training for use.




The present invention is concerned with a positive-pressure respirator hood assembly comprising, a gas-impermeable hood made of a flexible material, and comprising at least a portion which is a transparent visor, a gas treatment unit comprising a filter for filtering particles, fine spray, aerosols, and toxic and noxious gases etc. hereinafter “hazardous materials”), and a power-operated blower to generate a positive pressure wit the hood; a one-way purge valve for facilitating the exhaust of exhalation gases and moisture from the hood; and a sealing portion for sealingly securing the hood over a body portion of the user. The hood assembly is designed to allow near immediate donning to a wide range of users, requiring no training to don and operate the hood assembly, whereby a user is protected from inhalation of and facial contact with the hazardous materials.




The respirator hood is received within a container that is easily carried whereby upon opening the container and removing the respirator hood, the respirator hood is fully operational as the gas treatment unit is automatically activated. The respirator hood is foldable to allow it to fit within a small size container.




The hood, including the sealing portion, is designed such that one size provides protection from a toxic environment to users whether male or female, regardless of facial or head features such as beard, hair length/thickness, eyeglasses, etc, and regardless of size (from toddlers to large adults). The design of the hood also allows it to be used to protect animals such as pets, livestock, etc.




According to one embodiment of the invention, the sealing portion is an elastic neck seal and according to another embodiment, the sealing portion is a torso-engaging and sealing wrap.




The respirator hood may be carried and protected by a rigid container (case), in a flexible container or in a flexible container received within a case. Typically, the respirator hood is received within a sealed package for imparting it extended shelf life.




The respirator hood may be provided in some principal configurations, e.g. one for individuals from toddlers to adults, another for infants up to about the age of three years, and yet another for animals.




According to some particular designs, the operation of the blower can be stopped and the respiration hood may then be preserved for future use.











BRIEF DESCRIPTION OF THE DRAWINGS




In order to understand the invention and to see how it may be carried out in practice, a preferred embodiment will now be described by way of non-limiting example only, with reference to the accompanying drawings, in which:





FIG. 1

is a front view of a respirator hood according to one embodiment of the invention, being worn by a user;





FIG. 2

is a side view of the respirator hood of

FIG. 1

;





FIG. 3

is a general exploded view illustrating the respirator hood removed from its container;





FIG. 4A

shows a user carrying the respirator hood as a carry along device;





FIG. 4B

shows a user carrying the respirator hood in a briefcase;





FIG. 5

is a detailed isometric exploded view of the respiratory hood assembly, also showing the gas flow path through the gas treatment unit;





FIG. 6

is a top section of the respiratory hood assembly, illustrating an activation mechanism;





FIG. 7

is a side section of the respiratory hood assembly showing the hood to folded next to the gas treatment unit;





FIG. 8

is a front view of an alternate embodiment of the respirator hood used by an infant;





FIG. 9

is a rear view of the alternate embodiment of

FIG. 9

illustrating a sealing and closure means;





FIG. 10

is an alternate embodiment showing the respirator hood being removed from a flexible container;





FIG. 11

is an alternate embodiment of the respirator hood showing a packaging comprising a flexible container inside an outer case;





FIG. 12

is an exploded view of an alternate embodiment with re-insertable activation mechanism;





FIG. 13

is a top section of a gas treatment unit of an alternate embodiment highlighting the re-insertable activating mechanism; and





FIGS. 14A and 14B

are side views of alternate embodiments of the respirator hood used by dogs illustrating different closure means.











DETAILED DESCRIPTION OF THE INVENTION




The present invention is a respirator hood assembly that is portable, compact, easy to store, easy to carry, easy to don, easy and comfortable to use, is designed in a one-size-fits-all manner for users of a wide range of sizes, requires no training for use, and is activated and operates automatically.




Herein, the terms gas and gases are meant to denote the mixture of air and toxic and/or noxious gas or biological warfare agents, which may include particles, fine spray, aerosols, or droplets, collectively referred to as hazardous materials.




Referring fist to

FIG. 1

, a respirator hood, generally designated


10


, is shown which comprises a hood


12


, made of a flexible, gas and liquid-impermeable material and a gas treatment unit


14


attached to the hood


12


. The hood


12


includes a visor


16


, also made of a flexible, gas-impermeable material, positioned adjacent to the eyes of a user


18


.




Still referring to

FIG. 1

, fastened to the hood


12


is a sealing portion in the form of a collar or neck seal


20


made of an elastic material such as silicone, polyurethane, latex rubber, etc., allowing easy donning and requiring no latches, straps, ties, or the like. The neck seal


20


is sized to be, in the non-stretched condition, slightly smaller than that of a small toddler and whose material is such that it is easily stretched to a size conveniently larger than the head of a large adult user


18


regardless of long or thick hair, beards, etc. Further, the neck seal


20


is dimensionzed to be wide enough for wearing comfort. With this design, the respirator hood


10


is easily and conveniently donned within seconds by a wide range of individuals without need for training or operating instructions.





FIG. 1

further shows a cape or shroud


22


extending downward in a skirt-like manner fitting around tee neck toward the shoulders of the user


18


to protect the neck. A one-way purge valve


24


is integrated into the hood


12


to facilitate the exhaust of perspiration and exhalation gases such as carbon dioxide and moisture from the hood


12


while not allowing the entrance therethrough of outside gases. The one-way purge valve may be any suitable valve, outlet, or flow device, permitting the flow of gases, vapors or moisture in one direction only.




In

FIG. 2

arrow


26


shows where ambient gases enter the gas treatment unit


14


, arrow


28


shows where filtered air then enters the hood


12


, and arrow


30


shows where exhalation (exhaled air) and moisture exit from the hood


12


via the purge valve


24


. Seen again are side views of the visor


16


the neck seal


20


, and the shroud


22


.





FIG. 3

shows a respirator hood assembly


11


comprising the respirator hood


10


and its container, which is in the form of a rigid case, generally designated


32


, after the container


32


has been opened and the respirator hood


10


has emerged. At this point the respirator hood


10


is completely ready for donning and use. Container


32


comprises a front cover


34


and a rear cover


36


.




The covers


34


and


36


are not part of the respirator hood


10


that is worn by the user


22


, however they are important in that they form the container


32


which forms a protective casing around the respirator hood


10


in order ensure/prolong the shelf life. Optionally, a gas-impermeable seal is formed which prevents the ingress of humidity since filters of the type used in respiratory protective devices are sensitive to humidity. The container


32


can be carried using either of its front handle


38


and a rear handle


40


, which are part of the container


32


. The handles


38


and


40


are also used to open the container


32


, which automatically activates the gas treatment unit


14


, as described below. Additionally, the container


32


plays a significant role in activation of the gas treatment unit


14


, as will become apparent hereinafter.





FIGS. 4A and 4B

illustrate how the lightweight and compact respirator hood assembly


11


is easily carried by the user


18


as a carry along (

FIG. 4A

) or may fit within a briefcase


44


(FIG.


4


B). If carried as a carry along, as shown in

FIG. 4A

, the assembly


11


can include rings (not shown), or the like, for attaching an auxiliary carrying strap


42


. Desirably, the respirator hood assembly


11


fits into a portion of a typical small briefcase


44


. Analogously, the respirator hood assembly


11


can be carried in a purse or backpack (not shown).




The convenient carrying and compact storage features of the respirator hood assembly


11


are important in that they provide immediate availability of the respirator hood


10


to the user


18


. These features, along with the automatic activation of the gas treatment unit


14


(discussed below) and simple donning, allow he respirator hood


10


to be in fill use within seconds. Rapid deployment can be critical to the health, or even survival, of the user


18


.




In

FIG. 5

an arrow


46


indicates the gas flow path. Gases enter the gas treatment unit


14


firstly through an opening


48


in a housing


50


that accommodates the gas treatment unit


14


. The opening


48


is exposed to the ambient as soon as the front cover


34


is detached or removed. A washer


52


provides a seal between the housing


50


and a filter


54


that filters the incoming gases. The filter


54


is any suitable filter as known in the art for filtering of hazardous materials such as particles, toxic/noxious gases, fine sprays and aerosols. The filter


54


is sealed to a base


56


by a washer


55


. The base


56


is fitted on a manifold


58


. The manifold


58


distributes the gases, now filtered, back through an opening


60


of the base


56


. The filtered gases then enter and exit a battery powered blower


62


through a fitting


64


and an opening


66


. The blower


62


is sealed to the housing


50


by washer


67


. Through the opening


66


, the filtered gases enter the hood


12


. The hood


12


is fastened to the gas treatment unit


14


between the fitting


64


and a fitting


65


. The washers


52


,


55


and


67


are all replaceable by a suitable glue or other sealing compound such as silicone or epoxy.




Also seen in

FIG. 5

is a battery


68


that powers the blower


62


. The power is activated automatically when the covers


34


and


36


of the container


32


are opened, typically by handles


38


and


40


. An activating mechanism utilizing a latch


70


, a toggle


72


, and a switch


74


is explained below. The latch


70


sits in an indentation


76


(see also FIG.


6


). Fitting into the housing


50


is a blower cover


78


, which can be made in different configurations to add flexibility to the design of the components in the gas treatment unit


14


.




Blower


62


produces a positive pressure within the hood


12


which improves thee protection to the user


18


by preventing entry of gases via the neck seal


20


in the event the neck seal


20


is loose or if openings occur due to movement of the user


18


. The positive pressure produced by the blower


62


also prevents the entry of gases into the hood


12


as it is donned, prevents build-up of exhalation gases such as carbon dioxide and moisture (including the exhaust of perspiration, which improves the comfort of the user


18


).





FIG. 6

is a top section of the respirator hood assembly


11


showing the parts that activate the blower


62


. The latch


70


the top of which fits in the indentation


76


, is actuated when the front cover


34


is opened. Separating the cover


34


from the respirator hood


10


causes the latch


70


to rupture and thus in this embodiment the operation of the respirator hood


10


is irreversible once the respirator hood


10


is operated. As the front cover


34


is detached or removed, latch


70


is pulled outwardly and thereby pulls on toggle


72


which activates the switch


74


, thereby facilitating power to the blower


62


, which is powered by the battery


68


.





FIG. 7

shows a side section of the respirator hood assembly


11


, showing the hood


12


folded between the covers


34


and


36


. The compactness of the collapsible hood


12


is illustrated, as well as the fastening of the hood


12


to die gas treatment unit


14


by the fittings


64


and


65


.




To use the respirator hood


10


, the covers


34


and


36


, of container


32


, are separated detached and removed. The covers


34


and


36


are no longer needed. As is described above, this activates the blower


62


making the gas treatment unit


14


and respirator hood


10


fully operational. The neck seal


20


is then stretched over the head of the user


18


. There are no other actions necessary. Even if the respirator hood


10


is donned backward or to the side, i.e. with the visor


16


not in front of the eyes, the user


18


is still protected. Furthermore, the hood


12


, or a large enough portion of it, may be made of a transparent or translucent material affording the user


18


reasonable visibility. Alternatively, the hood


12


can be easily adjusted to a more appropriate. The positive pressure within the hood


12


, produced by the blower


62


, prevents ingress of the unwanted gases during any adjustment of the hood


12


. Thus, the respirator hood


10


is easily operated and used without the need for operating instructions even in time of stress.




It is appreciated that an untrained person of an age of from about three years to a complete, and large sized, adult can have ready access to, and can use a device according to the invention for head and neck protection and for the supply of pressurized purified air in the event of sudden exposure to toxic or noxious gases including particles, fine spray or aerosols.





FIG. 8

illustrates an alternate embodiment where an infant


90


uses the invention. It is dangerous to fit a neck seal around the neck of an infant


90


and so here a hood


92


which includes a visor


94


is designed to fit over the head and upper body of the infant


90


. The arms of the infant


90


may be completely inside the hood


92


(this option not shown) or may sealingly protrude tom the sides


96


and


97


which are formed when the hood


92


is closed around the torso of the infant


90


.





FIG. 9

illustrates one option of how the alternate embodiment shown in

FIG. 9

may be closed around the torso of the infant


90


. Any suitable closure means can be used, such as an elastic seal (analogous to neck seal


22


) suitable for an infant's torso, however, typically a hook and loop type fastener, commonly known as VELCRO™, is the most convenient. A portion containing hooks


98


and a portion containing loops


99


is shown. The hooks


98


and loops


99


potions can be reversed. This arrangement is also suitable for people suffering from neck injuries, etc.





FIG. 10

shows a different embodiment in which the respirator is contained in a flexible container such as a foil or laminated bag


110


. The bag


110


is made of a gas-impermeable material to protect the respirator hood


10


(especially the filter


62


from humidity, to ensure long shelf life) and is preferably made of a material that provides mechanical protection as well. Automatic activation in this embodiment can be achieved by various means including, for example, by activating a switch such as the switch


74


(

FIG. 6

) (or a switch


136


shown in

FIGS. 12 and 13

) which can be articulated with an opening edge


114


of the bag


110


, or a tear-ribbon, etc. The bag


110


preferably includes a handle


116


for easy carrying.




It should be understood that several variations on this embodiment are possible, including, but not limited to, one where the respirator hood


10


is activated by stretching the neck seal


22


before donning.





FIG. 11

illustrates a packaging arrangement in which the respirator hood


10


is contained in a flexible container such as a foil, laminated or plastic bag


118


which is further contained within an outer rigid container, generally designated


120


, which provides mechanical protection for the respirator hood


10


. The outer container


120


could be a rigid case, a tough sack or other suitable container. In this embodiment the bag


118


need not provide mechanical protection, but is still preferably made of a gas-impermeable material. The top cover


122


and bottom cover


124


may be held together by any suitable means such as mechanically, by pressure sensitive adhesive, etc.





FIG. 12

shows an exploded view of an alternate respirator hood assembly, generally designated


126


, emphasizing the internal components of an alternate gas treatment unit, generally designated


128


. In this embodiment the activation of a respirator hood, generally designated


130


, is reversible, i.e. it is possible to stop the operation of the gas treatment unit


128


and preserve it for future use. This is useful if, for example, the respirator hood


130


was accidentally activated or the user


18


escapes from, but needs to return to a toxic environment, etc.




An activation pin


132


, typically integral to a bottom cover


134


, penetrates into the gas treatment unit


128


compressing a switch


136


when the assembly


126


is in the packaged condition (best seen in FIG.


13


). Detaching or removal of the respirator hood


130


, from the bottom cover


134


detaches the pin


132


from the switch.


136


thereby actuating the switch


136


. The pin


132


can be re-inserted to re-compress the switch


136


and shut down the blower


54


of the gas treatment unit


128


to de-activate the respirator hood


130


.




Also shown in

FIG. 12

is a lip


146


on the cover


138


to aid in opening the covers


134


and


138


. A covering


148


, which is preferably a gas-impermeable material, in order to protect the gas treatment unit


128


from humidity/moisture, etc., is adjacent to the cover


138


and attached to cover


134


at its perimeter. A tab


150


is provided for easy peel back of the covering


148


. A handle


152


is integral to the over


134


, which along with the lip


146


makes for easy gripping of the assembly


126


. The handle


152


and the lip


146


are also used for easy opening of the covers


134


and


138


.





FIG. 13

shows a top section of the gas treatment unit


128


highlighting the re-insertable pin


132


which is part of the activation mechanism. Since the pin


132


is integral to the cover


134


, detaching or removal of the cover


134


detaches the pin


132


from the switch


136


. The blower


62


is thus actuated and the gas treatment unit


128


and the respirator hood


130


are then fully operational.





FIGS. 14A and 14B

show embodiments that are suitable for animals; depicted by a small dog


160


(

FIG. 14A

) and a large dog


162


(FIG.


14


B). For the small dog


160


a hook and loop closure means, discussed above for infants, may be appropriate. For a large dog


162


, a sealing portion such as the elastic neck seal


20


for a human adult user


18


may be appropriate. For animals, hoods


164


and


166


, including visors


168


and


170


, may require some size and shape differentiation from humans and size and shape differentiation from animal to animal depending on type and size. In the case of very small animals, for example gerbils (not shown), the animal, or more than one animal, can be completely inside the hood


164


;


166


.



Claims
  • 1. A positive-pressure respirator hood and container assembly comprising,a gas-impermeable hood made of a flexible material, formed with at least a transparent visor portion; a gas treatment unit, comprising a filter and a power-operated blower capable to force air through the filter and generate a positive pressure within the hood; a one-way purge valve for facilitating the exhaust of exhaled gases and moisture from the hood; a sealing portion for sealingly securing the hood over a body portion of the user; and a container for said hood; wherein said hood is compactly received within said container; and wherein, prior to removing the hood from the container, opening the container causes said gas treatment unit to be automatically activated by at least one activating member interacting between the hood and the container, thereby deploying the hood into an operating state such that said hood is conveniently available to the user to provide protection from toxic gases and particulate material.
  • 2. An assembly according to claim 1, where said container comprises a front and a rear cover, wherein separation of one cover from another allows opening the container and immediate deploying the respirator hood into the operative state.
  • 3. An assembly according to claim 1, where the body portion is a user's neck and where the sealing portion is a neck-engaging collar made of an elastic material.
  • 4. An assembly according to claim 1, where the sealing portion is designed to easily stretch over the head of the user and sealingly fit around the neck of the user after the hood is donned.
  • 5. An assembly according to claim 1, where the body portion is a user's torso and where the sealing portion is a torso-engaging and sealing wrap.
  • 6. An assembly according to claim 5, wherein the sealing wrap is adapted for elastic engagement over the user's torso.
  • 7. An assembly according to claim 1, where the respirator hood is adapted for wearing by an animal.
  • 8. An assembly according to claim 1, wherein the container comprises at least one detachable member articulated with an activating switch of the gas treatment unit, whereby detaching the member activates the power-operated blower.
  • 9. An assembly according to claim 1, wherein the gas treatment unit forcibly supplies filtered air into the hood giving rise to pressure build-up therein.
  • 10. An assembly according to claim 1, wherein the container comprises a front and a rear cover, at least one of which is articulated to an activating switch provided in the gas treatment unit.
  • 11. An assembly according to claim 10, wherein the front and rear covers are engageable into a closed position, wherein the respiratory hood and gas treatment unit are confined within the container in a gastight manner.
  • 12. An assembly according to claim 10, wherein at least one of the front and rear covers is fitted with a handle, to facilitate its detachment.
  • 13. An assembly according to claim 1, said assembly being deployable in a storage state and an operative state; wherein at said storage state the hood and the gas treatment unit are sealingly received within said container whereupon opening the container immediately and automatically activates the gas treatment unit.
  • 14. An assembly according to claim 13, wherein the container is rigid.
  • 15. An assembly according to claim 13, wherein the gas treatment unit comprises an activating switch coupled via a toggle member to a portion of the container, whereby opening the container automatically activates the switch.
  • 16. An assembly according to claim 15, wherein the toggle member is attached to one of the covers by a latch.
  • 17. A respirator hood according to claim 16, wherein the latch ruptures upon opening the container.
  • 18. An assembly according to claim 1, where the protection from toxic gases, particles, line spray, or aerosols is protection from inhalation.
  • 19. An assembly according to claim 1, where the protection from toxic gases, particles, fine spray, or aerosols is protection from contact.
  • 20. An assembly according to claim 1, in which said gas treatment unit is provided with a mechanically activatable switch.
  • 21. An assembly according to claim 1, where the assembly is easily and conveniently carried in a purse or briefcase and/or stored nearby the user.
  • 22. An assembly according to claim 1, where the assembly fits within a standard office briefcase.
  • 23. An assembly according to claim 1, where the assembly is designed as a one-size-fits-all above age of three.
  • 24. An assembly according to claim 1, where the hood is designed to fit users of a size range from toddlers to large adults.
  • 25. An assembly according to claim 1, where the hood is designed to fit users regardless of head or facial features.
  • 26. An assembly according to claim 1, where the hood is designed to fit users who have long hair or wear eyeglasses.
  • 27. An assembly according to claim 1, wherein the gas treatment unit is fixed to the respirator hood.
  • 28. A positive-pressure respirator hood and container assembly comprisinga gas-impermeable hood made of a flexible material, formed with at least a transparent visor portion; a gas treatment unit, comprising a filter and a power-operated blower capable to force air through the filter and generate a positive pressure within the hood; a one-way purge valve for facilitating the exhaust of exhaled gases and moisture from the hood; a sealing portion for sealingly securing the hood over a body portion of the user; and a container for said hood; wherein said hood is adapted to be compactly received within said container, and to be deployed into an operative state automatically, whereby a user is provided protection from toxic gases and particulate material, wherein the container comprises at least one detachable member articulated with an activating switch of the gas treatment unit, whereby detaching the member activates the power-operated blower, and wherein the at least one detachable member is re-insertable whereby the power-operated blower is de-activated.
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