Abstract:
A respiration hood assembly is effected from a thin-walled headpiece nested within the periphery of a mating exterior housing that includes a filtered aperture. The nested engagement between the headpiece and the housing is also useful in capturing one edge of a plastic membrane skirt that is thus suspended to drape over the person wearing the headpiece. A battery powered electric fan is deployed within the housing to draw ambient air through the vent aperture into the space shrouded by the skirt. The nested headpiece arrangement is useful in retaining other fibrous towels or tissue to extend the usefulness of the assembly and a parallel connection is provided to a motor vehicle battery to extend the period of electrical excitation.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to breathing devices, and more particularly to respiration hoods useful in protecting a person during biological or chemical emergencies. 
   2. Description of the Prior Art 
   Recent world events have drawn public concern, attention and focus to the persistent problem of terrorism. At the core is the paradox that the same information technology advances that have facilitated democratic governance have also found use in manipulating and then arming those that may disagree with the majority. Short term distortions in this information stream, by misinformation, disinformation and other manipulations, are now used successfully to motivate these dissident drives. Simply, the slow and deliberate processes of democratic consensus operate in the time domain of a fully developed information stream that is much slower than the psychological manipulation time constant of a single person, or a small group, of those on the fringe. To conceal the manipulator these manipulated fringes are then selectively directed to the same information technology for all sorts of chemical, biological, radiological, or even nuclear devices of terror. The majority then is either intuitively aware, or has been brought to awareness by recent events, of the pervasive existence of these manipulators together with the plentiful supply of the manipulated malcontents and the horrible prospects of this fertile combination now distort our ability to engage in clear thought. 
   These distorted perceptions stem from our current inability to fend for ourselves, to protect those that depend on each one of us, and some measure of individually accessible protection is necessary in order to carry on any rational democratic discourse. Against this backdrop being helpless is fundamentally antisocial, if not undemocratic. 
   Characteristically those who are manipulated to commit terror must lack the organization, skill repertoire and other attributes of a well organized social group—otherwise they reveal the social structure of the manipulator, who is then exposed to vigorous reprisal. For these reasons most of the terror devices are inherently less than well developed, being significant only for the fear and insecurity they create and not for the degree of their technical efficacy or development. The defensive devices to these items of terror similarly do not need to be at the zenith of perfection, needing only the basic attributes of protection but in a form that can be widely and inexpensively made and acquired and also easily used and thereafter disposed. Simply, the devices that allow us to fend for our selves must be fully democratic so that we can remain democratic. 
   Within the group of easily produced devices of terror it is those that rely on air borne delivery that are best defeated by self help. Thus air borne chemical agents, biological agents or even radiological agents are those that present the most immediate risk, being easily absorbed by skin contact or in the course of respiration. In the past various gas masks have been devised which in one way or another filter the breathing air exemplified by the various methods of their attachment or function in U.S. Pat. Nos. 5,630,412 to Dubruille; 6,470,887 to Martinez; 6,070,580 to McDonald, et al.; 5,771,886 to Maire, et al.; and 5,623,923 to Bertheau, et al. Alternatively, various respiration hoods in the prior art are exemplified in U.S. Pat. Nos. 6,102,034 to Buhlmann; 6,134,716 to Richardson, 6,371,116 to Resnick; 6,463,589 to Wang; 5,526,804 to Ottestad; and 5,452,712 to Richardson. While each of the foregoing are suitable for the purposes intended, none posses the simplicity and use convenience that is required in a terror emergency, and particularly the convenience that allows quick personal use thereof and quick deployment to protect an infant or a child. 
   Those skilled in the art will appreciate that a terror emergency event is usually recognized and announced way before its full scope and effectiveness are assessed. Thus there is both a circumstance where the protective response needs to be quick and also one that is basically uninformed about the event that is responded to. For example an alarm condition may be evoked by suspicions of a bacteriological (e.g., anthrax) event, a chemical (e.g., nerve gas) event, or a radiologic emission into the local atmosphere, each of which dictating a similar immediate response amongst the potentially exposed public regardless of the exact nature of the event. Universally these atmospherically carried hazards also define the primary exposure path as one associated with skin contact and respiration and it has long been recognized that filtering the aspirated air together with some passive shielding of the exposed skin surfaces provides the most practical level of protection. Thus the common attributes of the terror mechanism define the response and a simple, inexpensive and therefore discardable barrier that filters the respiration intake is extensively desired and it is one such barrier that is disclosed herein. 
   SUMMARY OF THE INVENTION 
   Accordingly, it is the general purpose and object of the present invention to provide a respiration hood provided with a self contained and filtered air transport mechanism for transmitting air into the interior thereof. 
   Other objects of the invention are to provide a respiration hood into which ambient air is drawn across a filtering medium and through an electrically charged field. 
   Further objects of the invention are to provide a respiration shield which includes conveniently discardable filtering elements. 
   Yet additional objects of the present invention are to provide a respiration shield that is easily worn and inexpensive in fabrication. 
   Briefly, these and other objects are accomplished within the present invention by providing a generally oval, dished shell conformed to include a head fitting piece on the interior thereof to receive the head of an adult person and including a forward portion extending above and forwards of the person&#39;s face. A flexible skirt is suspended from the periphery of the shell to extend over and drape the shoulders and chest of the user with that portion of the skirt extending over the user&#39;s face being spaced therefrom by the forward portion. The exterior surface of the shell is then also useful to support a housing enclosing an open brush electric motor driving a fan mounted in an aperture formed in the forward portion, the housing further including a removable filter behind a set of louvered openings formed in the top surface of the housing with the remaining housing volume storing both a battery and a parallel set of exterior terminals to power the motor. 
   Preferably the upper shell, the housing thereon and the skirt attached to its periphery are all formed of plastic materials characterized by a generally smooth, impervious exterior surface. Thus any air borne particulate matter settling on these exterior surfaces is prone to be easily shed, blown off or even washed off. To further enhance these shedding functions the louvered intake in the housing is located at its highest point, with the louvers shaped as saddle surfaces having few horizontal planes for accumulating dust and particulate matter. The polymeric material structure of the inventive hood assembly, moreover, cooperates synergistically with the open brush configuration of the electric motor which, in the course of its use, sheds a continuous ring of arcing and ionization at the brush to commutator interface, thus providing a source of an electrical charge field that is then useful to polarize the adjacent polymeric materials. This, of course, will aid in the charged retention of non-conducting particulate matter that may be collected in the filter while still accommodating the shedding of conductive metal particulates which, in the event of a radiological incident, are more prone to be radioactive. These electrical charge aspects can then be further utilized to advantage by the positional geometry of the motor within the housing immediately behind and adjacent the intake filter, thereby imposing the highest charge effects onto an element that is periodically replaced. 
   Those skilled in the art will appreciate that the same configuration of the hood that may be rendered useful to protect an adult is also useful, with simple attachment expedients, to shield the principal respiration paths of a child or even an infant. For example, the head piece may be provided with downwardly depending clips and straps for attachment thereof the a child&#39;s car seat, crib or even the child&#39;s clothing and the peripheral edge hoop of the skirt may be controlled in its free dimension by various snaps, thus rendering it adaptable to the smaller dimensions of a child or the seat or crib containing the child. The skirt material, moreover, may comprise a transparent membrane to facilitate convenient visual inspection of the person enclosed and further visibility enhancements may be effected by a layered, peelable panel in the line of vision of the wearer. In this manner a widely adaptable positive pressure enclosure is formed which effectively directs all air intake through a filter assembly. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective illustration of the inventive respiration hood in its deployed configuration on the person of a user; 
       FIG. 2  is yet another perspective illustration, separated by parts, of the inventive respiration hood assembly shown in  FIG. 1 ; 
       FIG. 3  is a sectional detail illustrating the filter receiving structure useful with the inventive respiration hood assembly disclosed herein; 
       FIG. 4  is a further perspective illustration of the inventive hood assembly deployed to shield an infant contained in a baby carrier; 
       FIG. 5  is an electrical circuit diagram useful with the invention herein; and 
       FIG. 6  is a diagrammatic illustration of the inventive hood assembly illustrating the air flow currents therethrough. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   As shown in  FIGS. 1 through 6  the inventive respiration hood assembly, generally designated by the numeral  10 , includes a molded plastic cap-like head piece  11  defined by a hemispherical cap or bowl  12  conformed to the skull dimensions of an adult person surrounded about the periphery of its opening by a generally circular brim  14  that extends eccentrically therefrom to deploy a forward portion  14   a  overhanging the person&#39;s face. The peripheral edge of brim  14  is rolled over to form a downwardly directed edge  15  supporting on its exterior an adhesive strip  16  to which the interior edge surface  21  of a flexible plastic membrane skirt  20  is adhered. In this form the head piece  11  once positioned on the head of a user deploys skirt  20  adhered to the peripheral edge  15  of brim  14  to drape over the back of the user&#39;s head, his or her shoulders and in spaced relationship in front of the user&#39;s face to then drape his or her chest, thereby providing a shrouded breathing space BC in front of the user&#39;s mouth and nose. This breathing cavity BC is ventilated at positive pressure by a circular fan  17  supported for rotation within a circular opening  14   b  formed through portion  14   a  and engaged to the output shaft  18   a  of an electric motor  18  fixed on posts or spacers  19  above the brim surface. The electric motor  18 , in turn, is powered by a battery  13  deployed on the back exterior surface of bowl  12  connected in parallel with a power cord  13   a  terminated for contact within a conventional cigarette lighter CL found in most motor vehicles. In this manner a continuous flow of air is delivered into the breathing cavity BC, drying and transporting away any moisture that may be emitted in the course of breathing to accommodate a clear view through a transparent viewing section  22  in skirt  20  which may be further protected against accumulation of obscuring dust on its exterior by a plurality of stacked, peelable films  23 - 1 - 23 - n  positioned thereon. 
   In this form the combination of the skirt  20  and the head piece  11  provide a shroud over the upper body of a person ventilated to positive pressure by the fan driven air flow AF right over the person&#39;s face. Any exit apertures that may be formed in the course of draping between the person and the lower skirt edge  25  will then be effectively emitting an outwardly directed stream of air, limiting all incidents of reverse ingestion of gas or air borne particulate matter. Thus only the air intake into fan  17  needs to be filtered and otherwise sanitized to protect the person that has donned this inventive shrouding structure, a filtering function contained in a mating dished exterior cover  31  provided again with a generally circular brim surface  34  surrounding a housing  32 . Brim surface  34  includes its own downwardly directed peripheral edge  35  dimensioned for receiving engagement of edge strip  15  with the skirt  20  adhered thereto. The upper portion of housing  32  is then provided with a generally rectangular cut-out  36  bordered by a recessed ledge  37  for supporting the edges of a rectangular filter element  38  thereon. A removable louvered cover  41  fixes the filter in place, admitting air into the housing interior through a set of louvers  42  that are each formed to define a saddle surface for convenient shedding of any particulates that may be collected on the housing exterior. 
   Those skilled in the art will appreciate that any terror event will invariably entail a wide particle size distribution, some particles approaching the dimensions of an aerosol while others of a mass to surface ratio that effectively limits any persistent air borne propagation. Since both particle ranges pose a hazard when accumulated, substantial improvements are achieved if the larger, more massive particles are shed before being trapped in the filter. For this reason a smooth exterior finish is provided to the dished cover  31  and to also to the surface of louvered cover  41 . Similarly, skirt  20  may be formed of a smooth plastic sheet material to promote shedding of any air borne particulates. 
   The collection and entrapment of the smaller, aerosol sized particulates, in turn, is improved by selecting an inexpensive open brush direct current motor configuration for motor  18  which in the course of its use produces an arcing ring. Motors of this type are generally less expensive as this commutator arcing is generally not desired because of the electrical noise that is usually created thereby. This arcing ionization, however, is used to advantage here by producing an electrostatic charge within the housing  32  which assists in the collection and entrapment of the small particles in filter  38 . 
   The foregoing nested arrangement of brim  14  within brim  34  is also useful to trap and retain other supporting structures between the opposed brim surfaces, expanding the utility of the inventive assembly. For example, a flexible panel  51  provided with an edge bead  52  may be retained between the rear portions of the exterior brim surface  34  and the subjacent surface of brim  14  with bead  52  captured in their common folds. As result a curved form is imparted to panel  51  increasing its stiffness and utility as a supporting structure. A set of clips  53 - 1  through  53 - n  at the other peripheral edges of panel  51  can then be utilized to fasten the combined structure to the adjacent folds of any apparel AP worn by the user, thus positively securing the inventive respiration hood to the person of the user, or as illustrated in detail in  FIG. 4 , securing the hood assembly  10  over a crib or infant seat assembly IA. Notably, the capture of panel  51  can be selected by the user to be on the exterior of skirt  20 , or on the skirt interior (not shown), where the clips and fasteners thereby provided can be used for other manners of attachment such as those that may need to be effected to provide a respiration shield for a wounded or incapacitated person. 
   One will appreciate that any significant terror event will invariably result in substantial public confusion and disruption of the ordinary routes of replenishment and supply. Any protective device, and particularly a device that seeks to shield critical life functions like respiration, will therefore need to be quite robust and susceptible to refurbishing or renewal by ordinary and widely available means. Thus while a sufficient supply of filter elements  38  may be included with the hood assembly for an anticipated exposure duration, in a setting where these exposure periods are exceeded, coupled with the need to frequently discard and seal the filter elements because of the hazard of the matter collected therein, alternative filtering mechanisms may need to be substituted to extend the needed shielding duration. In these extended eventualities some filtering degradation may need to be accepted and items of ordinary use, like paper napkins PN, may then be inserted and captured between the inner head piece  11  and the exterior housing  31 , either in conjunction with the filter elements  38  or as its replacement. Similarly, ordinary plastic sheeting, trash bags or other membranes may be substituted as the material forming skirt  20  in those instances where the original material is torn or otherwise damaged. In this manner the nested and interlocked arrangement between the brims of the interior head piece  11  and the exterior housing  31  offers wide levels of utility over extended periods of time and significant levels of degradation and it is exactly this kind of resilience that is needed in the exigent circumstances of a terror event. 
   Obviously, many modifications and variations can be effected without departing from the spirit of the invention instantly disclosed. It is therefore intended that the scope of the invention be determined solely by the claims appended hereto.