Patent Publication Number: US-2017361134-A1

Title: Breathing apparatus

Description:
TECHNICAL FIELD 
     The present invention relates generally to a breathing apparatus for providing filtered air to a wearer. In particular, the invention relates to a breathing apparatus having a ‘full face’ mask dimensioned to receive and cover a face of the wearer. 
     BACKGROUND TO THE INVENTION 
     Breathing apparatus, such as powered air purifying respirators (PAPR), are generally used in polluted environments to provide filtered, non-toxic air to a wearer. A PAPR device typically comprises a flow generator for generating filtered air, and a mask for communicating the filtered air to the wearer. The flow generator typically comprises a powered impeller arranged to draw air from the atmosphere and a filter element through which the air is passed and filtered. The filtered air is then conveyed to the wearer via the mask. 
     PAPR devices are often used in heavily polluted or otherwise hazardous environments, such as industrial areas or hospitals. In particular environments, it is desirable to provide a mask which substantially covers the wearer&#39;s face, known as a ‘full face’ mask, to protect the face from particulates or contaminants contacting the face. 
     Conventional PAPRs are generally bulky, restrict movement of the wearer and are therefore inconvenient and uncomfortable, particularly for prolonged periods of use. This is further exacerbated when a PAPR includes a full face mask, as this typically involves a hose which conveys the filtered air to the mask being connected to the front of the mask. This not only further restricts the movement of the wearer&#39;s head but also restricts its vision. These problems can be disincentives for using a PAPR device, potentially meaning that a PAPR is not used and consequently increasing health risks. 
     Accordingly, it would be useful to provide a breathing apparatus having a full face mask which restricts a wearer&#39;s vision and/or movement less than prior art approaches. Furthermore, it would be useful to provide a solution that avoids or ameliorates any of the disadvantages present in the prior art, or which provides another alternative to the prior art approaches. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the invention, there is provided a breathing apparatus comprising a face mask dimensioned to receive a face of a user and defining a peripheral region adapted to form a pneumatic seal against the face, and further comprising an air inlet arranged proximal to the peripheral region, and a neck component attached to the face mask and dimensioned to substantially surround a neck of the user, the neck component including a flow generator configured to receive unfiltered air from outside of the breathing apparatus, filter the unfiltered air, and convey the filtered air to the face mask through the air inlet. 
     Other aspects are disclosed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: 
         FIG. 1  is a perspective view of a breathing apparatus; 
         FIG. 2A  is an exploded view of part of the breathing apparatus shown in  FIG. 1 ; 
         FIG. 2B  is a perspective view of an air inlet valve shown in  FIG. 2A ; 
         FIG. 3  is a perspective view of an inner mask of the breathing apparatus shown in  FIG. 1 ; 
         FIG. 4  is another perspective view of the inner mask shown in  FIG. 3 ; 
         FIG. 5  is an alternative exploded view of part of the breathing apparatus shown in  FIG. 1 ; 
         FIGS. 6A to 6C  are perspective views of the breathing apparatus shown in the previous figures having a harness arrangement secured thereto; and 
         FIGS. 7A to 7C  are perspective views of part of the breathing apparatus shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The present disclosure relates to a breathing apparatus comprising a face mask dimensioned to receive a face of a user and defining a peripheral region adapted to form a pneumatic seal against the face, and further comprising an air inlet arranged proximal to the peripheral region, and a neck component attached to the face mask and dimensioned to substantially surround a neck of the user, the neck component including a flow generator configured to receive unfiltered air from outside of the breathing apparatus, filter the unfiltered air, and convey the filtered air to the face mask through the air inlet. 
     The disclosed breathing apparatus is a compact design comprising only the face mask and neck component, therefore ensuring the entire apparatus can be worn about the user&#39;s head. This is advantageous is this allows relatively free movement of the head and is comfortable to wear and use for prolonged periods. 
     The apparatus is firmly secured to the head by the face mask being retained relative to the neck component, thereby allowing the peripheral region of the mask to form a pneumatic seal against the face. An air inlet is arranged proximal to this peripheral region through which filtered air is conveyed by the flow generator arranged in the neck component. The position of the air inlet close to, or within, the peripheral region is important, as this prevents the fluid connection between the face mask and the neck component, which provides the filtered air to the user, interrupting the user&#39;s field of vision. This may involve the air inlet being arranged proximal to a portion of the peripheral region arranged to seal against the user&#39;s cheeks, or lower portion of the face. The arrangement of the air inlet proximal to the peripheral region also ensures the connection is conveniently located to optimise movement of the face mask, thereby enhancing manoeuvrability and comfort of the breathing apparatus. 
     The face mask typically includes a visor portion arranged at least partially across the face of the user, typically comprising a single surface which substantially covers the face. The air inlet is generally arranged to convey the filtered air into the face mask in a direction which is substantially tangential to the visor portion. This advantageously allows the filtered air to travel unencumbered across the face and access the user&#39;s airways, i.e. through the mouth and/or nostrils of the user. Furthermore, the tangential direction of the air inlet also allows the air inlet, and associated conduits or channels connected thereto, to be arranged close to the user&#39;s face/head, thereby minimising the size of the breathing apparatus and further enhancing manoeuvrability. 
     The breathing apparatus may also include an inner mask for covering the mouth and/or nostrils of the user, and conveying exhaled air out of the face mask. The inner mask is typically releasably engageable with the face mask by an engagement mechanism, allowing the inner mask to be readily assembled to the breathing apparatus when required. The engagement mechanism typically includes one or more deformable clips to optimise ease of assembling the inner mask to the face mask. This arrangement is therefore useful, as this allows the breathing apparatus to be conveniently and rapidly configured according to use requirements. 
     The face mask may include an additional connection to the neck component, being a strap which extends from the face mask, over the user&#39;s head, and is secured to the neck component, thereby suspending the neck component from the back of the user&#39;s head. The strap typically has a connector for releasably engaging the neck component. This arrangement supports the neck component away from the user&#39;s neck, thereby decreasing the load on the neck and improving the manoeuvrability and comfort of the breathing apparatus. 
       FIG. 1  shows a breathing apparatus  10  comprising a face mask  14  and a neck component  20  housing a flow generator  22 . The face mask  14  is dimensioned to receive a face of a user and defines a peripheral region  18  adapted to form a pneumatic seal against the face to create a breathing chamber  17 . An air inlet  50  for conveying air into the breathing chamber  17  is arranged proximal to the peripheral region  18 . The mask  14  has a visor portion  52  which at least partially, and typically substantially, covers the user&#39;s face, therefore providing a viewing window. The air inlet  50  is typically arranged to convey air therethrough substantially tangential to an adjacent portion of the visor  52 . An air outlet  51  for conveying air out of the breathing chamber  17  is arranged in a front portion of the face mask  14 . Each of the air inlet  50  and air outlet  51  may include a one-way (non-return) valve to control the flow of air therethrough in a single direction. The neck component  20  is releasably connectable to the face mask  14 . The connection between the neck component  20  and face mask  14  typically also forms a pneumatic seal between the flow generator  22  and the air inlet  50 . 
     In use, the face mask  14  is placed against the face of the user, forming a seal therebetween, and the neck component  20  connected thereto, thereby securing the breathing apparatus  10  to the user&#39;s head. The flow generator  22  is also connected to the air inlet  50  to provide fluid communication therebetween. When operated, the flow generator  22  draws unfiltered air from outside of the breathing apparatus  10 , filters the unfiltered air to produce non-toxic, filtered air, and conveys the filtered air through the air inlet  50 , into the breathing chamber  17 . The user inhales and exhales the filtered air, and the exhaled air passes through the air outlet  51 , out of the face mask  14  and away from the breathing apparatus  10 . 
     Optionally, the breathing apparatus further comprises an inner mask  12 . The inner mask  12  is dimensioned to receive a mouth and/or nostrils of the user and also defines a peripheral region  16  adapted to form a pneumatic seal against the face. The inner mask  12  is arranged within the breathing chamber  17  and includes one or more air inlets  32  for conveying the filtered air into the inner mask  12 , and covers the air outlet  51 , thereby allowing exhaled air to be conveyed therethrough. Each air inlet  32  also may include a one-way valve for controlling the flow of air therethrough in a single direction. 
     The peripheral sealing region  18  of the face mask  14  is typically arranged about a rear portion of the mask  14 . The region  18  includes a lower portion arranged to form the pneumatic seal against a corresponding lower portion of the user&#39; face, below the user&#39;s eyes. The lower portion also includes opposed cheek portions arranged to form the pneumatic seal against both of the user&#39;s cheeks. The air inlet  50  is generally arranged in the lower portion, and often arranged in one, or both, cheek portions. This minimises any visual obstruction caused by the air inlet  50  and also minimises any restriction to movement of the user&#39;s head. To further enhance the user&#39;s vision when using the apparatus  10  and minimise potential claustrophobic feelings, the face mask  14  and if assembled, the inner mask  12 , are substantially transparent or translucent. 
       FIG. 2A  shows an exploded view of the face mask  14 . Shown spaced apart from the air inlet  50  is a non-return valve assembly  26  comprising a row of three valves, although any plurality of non-return valves could be utilised. By having a plurality of non-return valves, the air flow resistance through each valve is reduced, which improves the flow of air into the breathing chamber  17  of the face mask  14 .  FIG. 2B  shows the non-return valve assembly in isolation. 
       FIGS. 3 and 4  show the inner mask  12  in isolation. The inner mask  12  comprises an engagement mechanism for releasably engaging the inner mask  12  with the face mask  14  and forming a seal therebetween. The engagement mechanism typically includes one or more resiliently deformable clips  30  arranged to engage a rim (not shown) arranged at least partially about the air outlet  51 . The engagement mechanism also typically includes a substantially rigid collar  28  dimensioned to abut the rim and form the seal. 
       FIG. 3  shows three air inlets  32  arranged in the inner mask  12 , each housing a one-way valve  32   a - 32   c . A first and second air inlet and associated valves  32   a ,  32   b  are arranged in opposed side portions of the mask  12 , and a third air inlet and associated valve  32   c  in a front portion of the mask  12 . Typically the peripheral region  16  includes a mouth portion arranged to form the pneumatic seal at least partially around the user&#39;s mouth and the front portion is arranged spaced apart from the peripheral region  16  and adjacent to, and typically below, the mouth portion. The arrangement therefore allows three, or potentially more, air inlets  32  to be provided, thereby optimising the rate filtered air is able to flow into the inner mask  12 . 
     Best shown in  FIG. 4 , the inner mask  12  also includes a nose portion arranged abut the nose of the user and which incorporates a resiliently deformable structure  34  which enables at least a portion thereof to flex to accommodate movement of the user&#39;s nose. The resiliently deformable structure  34  typically comprises a bellows arrangement, arranged to compress and expand, thereby enhancing the comfort of the breathing apparatus  10 . 
       FIG. 5  shows an alternative exploded view of the face mask  14 , showing one half of a cooperating mating clip  38  for releasably engaging the face mask  14  with a complementary half of the cooperating mating clip (not shown) affixed to the neck component  20 . The clip  38  is shown spaced apart from the air inlet  50  and is typically affixed to the air inlet  50 . The other half (not shown) of the clip  38  is typically affixed to an air channel extending from the flow generator  20  and arranged to convey the filtered air therefrom. Mating the two halves of the clip  38  together thereby allows a mechanical and pneumatic connection to be formed between the face mask  14  and the neck component  20 . One or more inserts may also be arranged in the air inlet  50  and/or associated air channel to prevent deformation of the channel and/or inlet  50 . 
       FIGS. 6A to 6C  show a harness arrangement attached to the breathing apparatus  10 . The harness arrangement connects between the face mask  14  and the neck component  30  to support the weight of the neck component  20  and distribute the load evenly across the user&#39;s head. 
     The neck component  20  connects to opposed sides of the face mask  14  and is arranged to surround the user&#39;s neck. The harness arrangement includes a head strap  40  connected between a top portion of the face mask  14  and a top portion of the neck component  20 . The head strap  40  may also have mask straps  41  extending therefrom to side portions of the mask  14 . 
     Typically, the head strap  40  is releasably connectable to the neck component  20  with a connector  42  secured thereto, the connector  42  adapted to engage with an attachment point  44  on the neck component. The attachment point  44  is formed along an arched beam extending from a top surface of the neck component  20 . The connector  42  is typically a resiliently deformable clip able to engage the attachment point  44  to suspend the neck component  20  from the harness arrangement, thereby reducing the weight of the breathing apparatus  10  supported on the user&#39;s neck and/or shoulders. The connector  42  and attachment point  44  are complementarily shaped to facilitate mating and disengagement of the two components, thereby providing a ‘quick release’ system which allows the user to readily secure and remove the neck component  20  to the harness arrangement. 
       FIGS. 7A to 7C  show the air outlet  51  of the face mask  14  in isolation. Optionally, the air outlet  51  further comprises an air quality testing conduit  55  arranged therethrough to allow test equipment (not shown) to be attached at either end thereof to determine air quality within the face mask  14  and potentially also compare this to air quality outside of the face mask  14 . Each end of the testing conduit  55  is shaped to engage with the test equipment, typically by frictional engagement. During a ‘normal use’ configuration of the breathing apparatus  10 , without testing equipment attached, a plug  56  is frictionally engaged with and seals an external end of the conduit  55 , thereby preventing unfiltered air entering the face mask  14 . Typically, the testing conduit  55  is arranged through the air outlet  51  to allow the testing equipment connected thereto within the mask  14  to be positioned proximal to the user&#39;s mouth, as this is the recommended location for testing air quality. However, whilst the testing conduit  55  is shown formed as an integral part of the air outlet  51  it will be appreciated that the conduit  55  may be formed in another part of the face mask  14 . 
     Whilst the invention is described above with reference to specific embodiments, it will be appreciated that it is not limited to those embodiments and may be embodied in other forms.