Abstract:
A face mask is provided having a filter body sized to cover the nose and mouth of a wearer, a securing mechanism for holding the filter body in close fit with the wearer&#39;s face, and a fan attachment to enhance breathability and comfort of the mask. The fan is powered and configured with the exterior of the filter body to aid in drawing air through the filter media of the mask. The fan operates to draw warm, moist exhaled air from the interior volume of the mask to improve comfort, facilitate inhalation, and decrease fogging of any transparent portions of the mask or eye coverings. The fan may additionally operate to force cool, fresh air into the interior volume of the mask, also for the comfort of the wearer.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to a face mask providing a covering for the nose and mouth of a wearer, and more particularly to a face mask with a fan attachment for drawing air through the filter body of the mask. 
     Disposable face masks and respirators are well known in the art. In the medical field, such masks are used in preventing contamination of a patient by the exhaled breath of healthcare personnel. In recent years, with increased concern for infection of healthcare personnel by airborne pathogens, such masks have become important in preventing infection of healthcare personnel as well. 
     Healthcare personnel now increasingly show a preference for wearing face masks which form a barrier or seal between the periphery of the mask and the face of the wearer. As a result of this sealing engagement between the mask and wearer&#39;s skin, substantially all air inhaled or exhaled by the wearer is forced to flow through the filter media of the face mask. As a result, these better-fitting filter masks can become hot and uncomfortable to the wearer during periods of long-term wear. Breathability can also be a problem. 
     In certain healthcare environments, there is a preference towards including transparent panels in face masks through which the wearer&#39;s face can be seen. These panels allow improved communication between healthcare personnel and patients by allowing the patient to see the mouth of the healthcare worker, and are particularly beneficial for serving hearing impaired patients. Such masks with transparent panels often have a problem with condensation because the warm, moist air exhaled by the wearer causes the panel to fog with moisture vapor. A similar condensation problem can occur when the face mask wearer must also wear eyeglasses or goggles. 
     The use of face masks with the noted associated problems is not restricted to the healthcare environment. Many industrial applications, such as handling hazardous materials or working in a clean room environment, also require the use of face masks and respirators that form a substantially tight seal between the face of the wearer and the periphery of the mask. 
     Accordingly, it can be seen that a need exists for a face mask design which provides increased air flow through the filter media of the mask by forcing exhaled air from the interior of the mask and delivering fresh air from the exterior of the mask. 
     SUMMARY OF THE INVENTION 
     The present invention recognizes and addresses the foregoing disadvantages, and others, of prior art construction and methods. 
     Objects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention. 
     In accordance with the invention, a face mask is provided having a filter body to cover at least the nose and mouth of a wearer and defining an interior air volume surrounding the wearer&#39;s nose and mouth. The face mask also includes a mechanism for holding the mask securely on the wearer&#39;s face. A fan is disposed on the outside of the filter body which can operate to draw at least a portion of its air flow through the filter body of the mask. 
     In one desired embodiment, the filter body of the face mask forms a substantially tight seal with the face of the wearer when in use. The mechanism for securing the mask to the face of the wearer aids in holding the periphery of the mask in this sealing engagement with the skin. The securing device may be any conventional device, including tie straps or elastic straps to go around the back or top of the wearer&#39;s head, ear loops, or the like. 
     The fan may be operational in a direction to draw air exhaled by the wearer from within the interior air volume of the mask, effectively removing the hot, moist breath of the wearer and allowing the wearer to inhale with greater ease. Removal of exhaled air also helps prevent fogging of eyeglasses and any clear portion of the mask. 
     In another embodiment, the fan is reversible and thus may be configured to either draw exhaled air out of the interior volume of the mask or draw cool, fresh air into the interior volume of the mask providing greater comfort to the wearer. 
     The fan may be powered using a power supply such as batteries or other access to electrical current. The power supply may be portable and have the ability to be remotely positioned away from the fan and mask, for instance, attached to the wearer&#39;s belt. 
     In another embodiment, the fan may be connected to an electrical supply provided in hospital operating rooms or other facility. 
     The power supply for the fan may be included in a fan controller which allows the fan to be turned on and off. The controller may also have the ability to be remotely positioned from the fan and mask for comfort and convenience. The controller may also allow selection of the speed for the fan as well as its operational direction if the fan is reversible. 
     In one embodiment, the fan may be permanently affixed to the exterior surface of the mask using means such as an adhesive and like. In another embodiment, the fan may be removably secured to the exterior surface of the mask using snaps, a pocket of material, or similar securing mechanisms. This embodiment allows the fan to be reusable on any number of disposable face masks. 
     In one desirable embodiment, the fan is attached directly adjacent to the filter media of the face mask. The fan may also include an air filter to further enhance filtering of the air forced through the mask by the fan. The further air filter may be particularly beneficial in an embodiment in which the portion of the filter body adjacent to the fan has a differing filter capability from the rest of the mask. For instance, the fan may be attached to a portion of the filter body with enlarged perforations. Alternatively, the fan may be sealed into a port in the filter body of the mask. 
     The filter body of the mask may include an upper portion with a top edge arranged to extend across the nose and cheeks of the wearer and a lower portion having a bottom edge arranged to extend under the chin of the wearer, with the fan disposed on the lower portion. In one embodiment, the upper and lower portions of the mask may be of generally trapezoidal shape with the longer top and bottom edges forming the periphery of the mask to be held in substantially sealing engagement with the wearer&#39;s face, the upper and lower portions of the mask joined together along the remaining edges. Any number of configurations of the filter body are within the scope of the invention. 
     The filter body of the mask may also include a panel of transparent material to allow the wearer&#39;s mouth to be seen through the mask. In this embodiment, the fan prevents condensation from forming on the transparent portion of the mask by drawing moist, exhaled air from the interior volume of the mask. 
     It should be appreciated by those skilled in the art that the present invention has many applications in the medical field and in industrial environments. The invention can be adapted to a wide variety of face masks. Other features and aspects of the present invention are discussed in greater detail below. 
     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate a number of embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A full and enabling disclosure of the present invention, including the best mode thereof and directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended drawings, in which: 
     FIG. 1A is a perspective view of a face mask with fan attachment designed in accordance with the present invention; 
     FIG. 1B is a sectional side view of the fan as attached in the embodiment of the device illustrated in FIG. 1A; 
     FIG. 2 is a perspective view of the face mask illustrated in FIG. 1, further showing a fan controller; 
     FIG. 3 is a perspective view of another embodiment of a face mask with fan attachment designed in accordance with the present invention; and 
     FIG. 4 is a perspective view of another embodiment of a face mask with fan attachment designed in accordance with the present invention. 
     Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made in detail to the presently preferred embodiments of the present invention, one or more examples of which are illustrated in the drawings. Each example is provided for explanation of the invention and is not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to create still a third embodiment. It is intended that the present invention cover such modifications and variations as come within the scope and spirit of the invention. 
     Referring to the figures in general, face masks  10 ,  110 , and  210  are illustrated, positioned on the face of a wearer  12  and including an attached fan  14 . As described herein, the face masks can be used to prevent or retard the flow of airborne pathogens, particulate matter, or hazardous materials from the exterior of the masks to the nose and mouth of the wearer  12 . Additionally, the masks may prevent bacteria and other contaminants from leaving the body of the mask. Each mask illustrated includes a filter body  16  or filter portion  18  for filtering out harmful matter. 
     Preferably, each of the masks illustrated fit the face of the wearer  12  in a substantially sealed engagement causing the air inhaled and exhaled by the wearer  12  to pass primarily through the filter body  16  or filter portion  18  of the mask. Fan  14  is particularly useful in such an arrangement to aid air passage through the filter media. 
     As illustrated in FIGS. 1A and 2, the filter body  16  of face mask  10  may comprise an upper panel  20  and a lower panel  22  of generally trapezoidal shape. The upper panel  20  and the lower panel  22  may have an identical configuration and may be bonded together along three sides. The fourth, unbonded side of the upper panel  20  comprises the top edge  24  of the mask and extends across the nose and cheeks of the wearer  12 . Similarly, the fourth, unbonded side of the lower panel  22  comprises the bottom edge  26  of the periphery or opening of the face mask  10  and is positioned beneath the chin of the wearer  12 . Such a mask is described in U.S. Patent Reexamination Certificate B1 5,322,061, issued on Jun. 2, 1998, for U.S. Pat. No. 5,322,061, issued to Brunson on Jun. 21, 1994, the entire disclosure of which is hereby incorporated by reference. 
     As illustrated in FIGS. 1A and 2, the filter body  16  of face mask  10  is held against the wearer&#39;s face by a securement means or mechanism which preferably causes the periphery of the mask to form a substantially tight seal with the wearer&#39;s skin. The securing mechanism may comprise resilient, elastic straps  28  and  30  extending respectively from top edge  24  and bottom edge  26  of the periphery of the mask in a generally linear configuration. As can be seen, strap  28  extends behind the head of the wearer  12 , and strap  30  extends around the top of the head of the wearer  12  to secure the mask to the wearer&#39;s face in a substantially tight engagement. This type of securing mechanism is but one of any number of well known devices that may be used with the present invention. 
     As further illustrated in FIGS. 1A,  1 B and  2 , the present invention incorporates a fan  14  into the face mask described above in a preferred embodiment. Fan  14  may be a simple lightweight fan in plastic casing  15 . Applicant has found that a suitable fan is the type as may be provided for cooling in a computer hard drive. The fan  14  can be disposable, semi-disposable, or reusable. The fan  14  may run at a number of speeds or only a single speed. In a preferred embodiment, fan  14  is attached to the lower panel  22  of face mask  10  to most efficiently draw out exhaled air as it enters the interior volume of the mask from the nose and mouth of the wearer  12 . 
     In a desired embodiment, the fan is operational in a direction to draw exhaled air from within the interior volume of the mask  10 , in order to enhance breathability and comfort to the wearer  12 . Alternatively, the fan  14  may be reversible to allow the wearer  12  to switch the direction of the fan, choosing between a direction to remove exhaled air from the interior volume of the mask  10  or a direction to draw cool, fresh air into the interior volume of the mask  10 . Fan  14  could be restricted to one direction as necessary, for example, in a hazardous environment where forcing exterior air into the mask might also bring in harmful matter. 
     The fan  14  may be attached to the mask  10  in any number of ways. Fan  14  may be permanently attached to the mask  10  with adhesive  34  or the like as illustrated in FIG.  1 B. Alternatively, the fan may be removably attached, for example, using a snap-in method, a pocket of material, or with material hooks such as Velcro®. Such a removable attachment arrangement would allow the use of a reusable fan with a disposable mask. In some environments, it will be preferable that both the mask and the fan be disposable. 
     Fan  14  may also include an air filter  17  to aid in filtering the air forced through the filter media of the mask. The portion of the mask  10  adjacent fan  14  may be formed from different material than the rest of the filter body  16  or filter portion  18 . For example, the filter media may be altered to allow increased air flow in that area only. The inclusion of an air filter  17  with fan  14  would be useful in such an arrangement. Similarly, an additional air filter would be helpful if mask  10  is configured with a opening (not shown) allowing fan  14  to be sealed into the periphery of the opening. 
     In the embodiment illustrated in FIG. 2, fan  14  is connected to a fan controller  36 . The controller  36  may include an on/off switch  38 , a mechanism  40  for controlling the speed of the fan, and a switch  42  to select the direction of the fan  14 , in the case of a reversible fan. 
     As is illustrated in FIG. 2, the fan controller  36  may be separate from the fan  14  which would be preferred to prevent additional weight on the face mask. This arrangement would allow the wearer  12  to position the controller  36  away from the fan  14  and mask  10 , for example, by hooking the controller  36  to another part of the wearer&#39;s clothing. 
     The controller  36  may also include a power supply (not shown) for the fan  14 , for example, a battery pack. Alternatively, the power supply for the fan  14  could be a remote fixed supply such as an electrical outlet or other electrical sources. 
     An alternative embodiment for the present invention is illustrated in FIG.  3 . Mask  110  is a traditional cone mask, well-known in the art. Cone mask  110  is defined by a border  44  defining the opening  46  of the mask and molded to fit snugly around the nose, cheeks, and chin of wearer  12 . Attaching strap  48  works in conjunction with border  44  to ensure a close fit and minimize the passage of air around the edge of mask  110 . Fan  14  may be positioned anywhere on the filter body  16  of cone mask  110 . In a preferred embodiment, the fan is positioned on the lower portion  50  of mask  110  for more efficient removal of exhaled air. 
     FIG. 4 illustrates another preferred embodiment of the present invention and shows the use of fan  14  on a face mask  210  with a transparent portion  52 . Fan  14  can be particularly beneficial when used with such a mask because fan  14  can facilitate the removal of warm, moist exhaled air, thus preventing condensation from forming on the transparent portion  52 . Face masks  210  with a transparent portion  52  allow the wearer&#39;s mouth to be seen from outside the mask, allowing the wearer  12  to communicate more easily. Such a mask is described in U.S. Pat. No. 5,561,863, issued to Carlson, II on Oct. 8, 1996, the entire disclosure of which is hereby incorporated by reference. 
     As shown in FIG. 4, mask  210  may have a top edge  54  extending across the nose of the wearer  12  and further forming an attaching strap  56  positioned around the wearer&#39;s head. Mask  210  also has a bottom edge  58  extending under the chin of the wearer and further forming an additional attaching strap  60  which extends around the head or upper neck of the wearer  12 . To complete the periphery of mask  210  surrounding the nose and mouth of the wearer  12 , side edges  62  connect the top edge  54  and the bottom edge  56 . 
     The body of mask  210  consists of a transparent portion  52  which allows viewing of at least the mouth of the wearer and a filter portion  18  forming the lower portion of mask  210 . In a preferred embodiment, fan  14  is attached to the filter portion  18  of mask  210  and, as described above, operates to draw air through the filter portion  18 . 
     While preferred embodiments of the present invention have been described above, it is to be understood that any and all equivalent realizations of the present invention are included within the scope and spirit thereof. Thus, the embodiments depicted are presented by way of example only and are not intended as limitations upon the present invention. While particular embodiments of the invention have been described and shown, it will be understood by those of ordinary skill in this art that the present invention is not limited thereto since many modifications can be made. Therefore, it is contemplated that any and all such embodiments are included in the present invention as may fall within the literal or equivalent scope of the appended claims.