Patent Publication Number: US-2022219023-A1

Title: Personal air purifying respirator

Description:
TECHNICAL FIELD 
     The present disclosure relates to personal air purifying respirators. 
     BACKGROUND 
     Personal air purifying respirators are used to filter contaminated air and provide clean, breathable air to a user. The respirator includes a filter configured to block pathogens, dirt, and other contaminations from entering the user&#39;s respiratory system. 
     SUMMARY 
     According to one embodiment, a respirator includes a head unit configured to be received on a human head and a purifying unit configured to provide purified air to the head unit. The purifying unit includes a first housing portion having an interior side defining a blower cavity, an exterior side defining a partial filter chamber with a filter sealing surface, and an inlet hole circumscribed by the sealing surface and extending between the interior and exterior sides. A second housing portion has an interior side defining a blower cavity. The first and second housings are attached to each other to form a housing such that the blower cavities are opposite each other to define a blower chamber within the housing. A blower is disposed in the blower chamber. A filter covers over the inlet hole and is disposed against the sealing surface such that air entering the hole must pass through the filter. 
     According to another embodiment, a respirator includes a head unit configured to be received on a human head and a purifying unit configured to provide purified air to the head unit. The purifying unit includes a housing formed of a pair of front and back halves that are secured together to form the housing. The housing defines a blower chamber, an electronics-and-battery chamber, a filter cavity with a sealing surface, and an inlet hole connecting the blower chamber and the filter cavity. A blower is disposed in the blower chamber, and a filter is disposed in the filter cavity. The filter covers the inlet hole and is disposed against the sealing surface. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a personal air purifying respirator. 
         FIG. 2  is an exploded view of the respirator. 
         FIG. 3  is a perspective view of an exterior side of a back housing portion. 
         FIG. 4  is a perspective view of an interior side of the back housing portion. 
         FIG. 5  is a perspective view of an exterior side of a front housing portion. 
         FIG. 6  is a perspective view of an interior side of the front housing portion. 
         FIG. 7  is a side view, in cross section, an air purifying unit of the respirator. 
         FIG. 8  is a perspective view of an air outlet adapter for hose connection. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations. 
     Referring to  FIG. 1 , a personal air purifying respirator  20  includes a head unit  22  to be worn over a user&#39;s head and face. The head unit  22  includes a face shield  24 , such as clear glass or plastic, and a hood  26 . The hood  26  includes an upper portion  28  that is received over the head and a skirt portion  30  that depends downwardly and is received over the shoulders. The head unit  22  is designed to provide a sealed environment around the users face to prevent contaminants from entering therein. The hood  26  includes an air inlet port (not visible) that receives purified air from the purifying unit  32 . For example, a flexible hose  34  connects the outlet manifold  36  of the purifying unit  32  to the inlet port of the hood  26 . The purifying unit  32  may the designed to be worn on a users back and may include a belt  37  for securing the unit  32  to the user. 
     Referring to  FIGS. 2, 3 and 4 , the purifying unit  32  may generally include a blower portion  40 , a filter portion  42 , and an electronics-and-battery portion  44 . The purifying unit  32  includes a housing  48 , a filter cover  50 , an electronics cover  52 , and a battery cover  54 . The housing  48  and covers may be formed of injection-molded plastic components. In the illustrated embodiment, six injection molded plastic components are used. The housing  48  may be formed of two plastic-injection molded components (halves) that are secured together, e.g., a clamshell design. Use of the term “housing halves” does not necessarily mean that each half forms exactly half of the housing. The housing  48  may include a back housing portion (or half)  56  including an external side  58  and an internal side  60 . The back housing portion  56  includes a blower cavity  62  and a battery-and-electronics cavity  64 . The blower cavity  62  includes a pair of concentric circular supports or walls  66  and  68 . The outer support wall  68  forms a support for the blower (not shown) and the inner guide wall  66  defines the air inlet to the blower portion  40 . Another guide wall  70  surrounds the blower and generally defines the blower cavity  62 . During operation of the blower, air is drawn in through the inlet  66  and forced radially outward into the guide wall  70 . The guide wall  70  is configured to direct the pressurized air to the outlet manifold  36 . 
     The walls  66 ,  68 , and  70  extend from a wall  72 . The wall  72  includes an outer border  74  that is generally planar and an inner portion  76  that tapers inwardly. The inner portion  76  may be generally pyramidal in shape. A front side  78  of outer border  74  forms a sealing land for the filter  82 . An outer filter wall  84 , which may be rectangular and have four sides, extends perpendicularly from the front side  78  and cooperates with the wall  72  to define a portion of the filter cavity  86 . A plurality of alignment tabs  88  are formed on the filter wall  84  and the front side  78 . The tabs  88  cooperate to center and align the filter  82  within the filter cavity  86 . The tabs  88  are configured to engage with a frame  84  of the filter  82 . The tabs  88  may be slender rectangles, as shown, or any other suitable shape. 
     The back housing portion  56  may also define a portion, e.g., roughly half, of the battery-and-electronics chamber  65 . For example, the back housing portion  56  may include opposing walls  90  and  92 , a wall  94  connecting between the walls  90  and  92 , and an end wall  96 . The wall  92  includes one or more feet  98  that support the unit  32  when not in use. The wall  92  also defines a notch  100  for the ON/OFF switch  104 . The notch  100  is disposed on a recessed portion  102  of the wall  92 . The recessed portion  102  reduces the likelihood of the switch  104  being inadvertently actuated and protects the switch from being damaged. 
     Referring to  FIGS. 2, 5 and 6 , a front housing portion (or half)  110  may roughly define the other half of the housing  48 . The front housing portion  110  includes an external side  112  and an internal side  114 . The internal side  114  defines another blower cavity  115  and includes a second guide wall  116  that is sized and shaped to align with the guide wall  70  when the front and back housing portion are joined. When the front and back housing portions come together, the blower cavities  62  and  115  align and cooperate to form the blower chamber  117 . The guide walls  70  and  116  cooperate to define some walls of the blower chamber  117  and guide the flow of air through to outlet manifold  36 . The front housing portion  110  also includes an inner circular wall  118  that is configured to route air around the blower assembly. The walls  116  and  118  extend from an interior side  122  of a front wall  120 . An exterior side  124  of the front wall  120  is configured to rest against the back of the user when in use. 
     The front housing portion  110  includes another portion that cooperates with the back housing portion  56  to define the battery-and-electronics chamber  64 . Like the back portion, the front portion  110  also defines a battery-and-electronics cavity  106  designed to come together with the cavity  64  of the back portion  56 . For example, the front cover  110  may define, at least partially, three walls of the cavity  106 . The front cover may include a wall  126  that joins to the wall  92  to generally form a bottom of the unit  32 , a wall  128  that joins with the wall  96  to form a closed end of the electronics- and-battery portion  44 , and a wall  124  that is opposite the wall  94 . The wall  125  defines an opening  127  for the electronics  140 . A cover  52  is configured to seal the opening. The cover  52  may be secured to the wall  125  by a plurality of fasteners, clips, snaps, hinges, or the like. 
     The outer wall  130  is sized and shaped to align and connect with the outer wall  132  of the back housing poriton  56 . The edges of the walls  130 ,  132  may cooperate to define a cavity for receiving a seal (not shown) to create an airtight seal between the front and back covers  110 ,  56 . The seal may be a gasket or may be an adhesive or bonding material. The front and back portions  56 ,  110  are secured to each other by a plurality of fasteners  134  that are received through one or more tabs  136  formed on the front and back covers. 
     The electronics-and-battery portion  44  has an open end  146  that allows access to a rechargeable battery that is removable from the unit  36 . The battery cover  54  is connectable to the opened end  46  to close the electronics-and-battery chamber. The cover  54  may be secured by a plurality of fasteners, clips, snaps, hinges, or the like. 
     Referring to  FIGS. 2 and 7 , a blower  150  is disposed in the blower chamber  117 . The blower  150  includes a fan  152  operably coupled to a motor assembly  154 . The blower  150  may be supported in the chamber  117  by a plurality of mounting posts  156  that are part of the back housing portion  56  and extend from the wall  72 . The fan  152  may be an axial fan that draws air into the center of the fan  152  and expels air radially outward with a series of vanes (or blades)  154 . 
     The motor assembly  154  includes a frame that supports the electric motor. The electric motor  155  may include a stationary stator and a rotor that is mounted for rotation within the stator. A spindle of the motor assembly is rotationally fixed to the rotor. The fan  154  is mounted to the spindle to operably coupled the fan to the motor  155 . When the motor is energized, the fan  154  is rotated to provide a flow of air to the head unit  22 . The blower  150  may be a high-efficiency blower that enables the battery  148  to operate for an extended period of time, e.g., 12 hours, without requiring recharging or battery change out. 
     The filter  82  is disposed upstream of the blower  154  within the filter cavity  86  of the housing. A filter cover  50  is connected to the housing to form the filter chamber  87 . The filter chamber  87  is defined by the cooperation of the back housing portion  56  and the filter cover  50 . The filter cover  50  includes walls  160  that engage with the walls  84  of the back portion  56 . A gasket, adhesive or other sealing means may be placed between the edges of the walls  84  and  160  to provide an airtight seal. The cover  50  includes a face  162  that connects between the walls  160 . The cover face  162  defines a plurality of air inlets  164 , e.g., slots, slits, holes, etc., that allow raw air into the filter chamber  87 . 
     The filter  82  is received within the filter chamber  87  with a gasket  170 , which is supported on the frame  84 , disposed against the sealing surface of the border  74 . The gasket  170  is configured to create an airtight seal to prevent contaminated air from entering into the blower chamber. The filter  82  is also received within the filter chamber  86  with the frame  84  disposed against the tabs  88  to provide proper alignment. 
     During operation, the blower  150  draws raw air into the filter chamber  87  through the air inlets  164 . The air then passes through a filter medium  83  of the filter  82 , which removes contaminants such as viruses, pathogens, bacteria, molds, dirt, chemicals, and other unwanted substances. The filter  82  may be a high-efficiency particulate air (HEPA) filter. Cleaned air emerges from the clean side of the filter  82  and is guided to the blower chamber  117  by the tapered walls  76  and the guide wall  66 . The guide wall  66  conveys the air from the filter  82  to the center of the fan  154  (suction side). The rotating vanes  154  force the air radially outward and through the outlet manifold  36 . 
     The outlet manifold  36  defines an outlet port  172 , e.g., a circular hole defined by the cooperation of the front and back housing portions  56  and  110 . The outlet manifold  36  is configured to connect to the inlet fitting  176  of the hose  34  either directly or via an adapter  178 . The other fitting  177  of the hose is configured to connect with the port on the head unit  22 . In order to create an airtight seal, the hose fitting  176  must match the outlet manifold  36  or the adapter. Without the adapter, the cooperating fitting  180  of the outlet manifold  36  must be specifically designed for use with the fitting  176  of the hose. Since this fitting  180  is injection molded with the remainder of the housing  40 , a redesign of the housing  40  would be required if a different type of hose fitting was used. To avoid this, the adapter  178  may be provided. The adapter  178  includes a first fitting end  182  that matches the fitting  180  of the outlet manifold  36 . The other end of the adapter  184  is designed to interface with the hose fitting  176 . Therefore, all that needs to be redesigned is a new adapter  178  should different hoses be used. 
       FIG. 8  illustrates one example embodiment of the adapter  178 . The adapter  178  may include a cylindrical body  190  defining a hollow center  192  that allows air to pass therethrough. The adapter  178  includes an inlet side  190  that is designed to be connected to the fitting  180  of the housing  40 . The outlet side  194  includes a fitting designed to be connected to a desired hose fitting, such as fitting  176 . 
     Referring back to  FIG. 2 , performance of the respirator  20  is highly dependent on the proper assembly and placement of the filter  82 . The filter  82  may be directional, and to function appropriately, the filter must be installed in the device in the correct orientation. The filter  82  may include an arrow  198 , or other indicia, the indicates the correct orientation of the filter  82  within the filter chamber. To allow for easy checking of filter orientation, the cover  50  may define a notch, cut out, window  200  that provides viewing of the arrow  198  so that a fully assembled product can easily be inspected. 
     The blower is controlled by a circuit  140  that includes a controller or micro-processor configured to at least operate the blower. 
     The ON/OFF switch  104  is electrically connected to the circuitry  140 . Pressing the switch  104  ON causes the circuitry  142  activate the blower  150  and begin operation of the respirator  20 . Similarly, pressing the switch  104  OFF ceases operation of the blower. The switch  104  may be a toggle switch for example having an ON position in an OFF position. Alternatively, the switch  104  may be a pushbutton which cycles between ON and OFF each time it is pressed. A course other types of ON-OFF switches are known and may be used. 
     Control circuit  140  is powered by battery  148 . The battery  148  is configured to be removably connected to the unit  32 . The battery  148  may be a lithium-ion battery or other suitable chemistry. The battery  148  is a rechargeable battery that may be removed from the unit and plugged into a charging station (not shown) to recharge the battery. This allows the respirator  20  to be continuously utilized whenever a charged battery is available. For example, the respirator  20  may be provided with two or more batteries allowing one of the batteries to be charged while the other batteries used so that at any given time, a functionally charged battery is available. The battery may also be chargeable within the unit. 
     A battery dock  202  may be provided within the electronics-and-battery portion  44 . The battery dock  202  includes terminals configured to connect to terminals of the battery  148 . The battery dock  202  may be connected to the circuit  140  by one or more wires  204 . The battery dock  202  may include retention features that cooperate with retention features on the outer housing of the battery  148  to provide a secure connection therebetween. These retention features may include release mechanisms allowing the battery  148  to be disconnected from the dock  202 . The cover  54  is removable, or otherwise openable, to allow access to the battery  148  through the open end. 
     The proposed respirator  20  is designed to simplify manufacturing steps and take advantage of quickly adaptable tooling in order to produce a large amount of the respirators  20  within a very short time. This is particularly helpful during an emergency, such as a pandemic, in which respirators become in short supply due to limitations of the traditional manufacturers and additional parties are recruited to fill this shortage. For example, the respirator  20  takes advantage of injection- molded components that are easily ramped up with minimal tooling time and costs. Injection-molded components of the housing and the like of the respirator  20  are also easily assembled together through simple tools and fasteners. This allows the respirator  20  to be manufactured on an emergency basis by parties that are not traditional players in the segment. 
     While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments can be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics can be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. These attributes can include, but are not limited to cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and can be desirable for particular applications.