Patent Publication Number: US-11376449-B2

Title: Mask device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority to Korean Patent Application Nos. 10-2018-0169608 filed on Dec. 26, 2018; and 10-2019-0089148 filed on Jul. 23, 2019 with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. 
     FIELD OF THE DISCLOSURE 
     The present disclosure relates to a mask device. 
     BACKGROUND 
     In general, a mask refers to a device for covering a user&#39;s nose and mouth to prevent inhalation of germs, dust, and the like. The mask adheres to the user&#39;s face to cover the user&#39;s nose and mouth. The mask filters germs, dust, and the like contained in the air flowing into the user&#39;s nose and mouth, and allows the user to breath in filtered air. Germs, dust, and the like contained in the air pass through the body of the mask that includes a filter, and the germs, dust and the like are filtered by the body of the mask. 
     However, after passing through the body of the mask, the air may flow into the user&#39;s nose and mouth, or the air may flow out of the mask, and thus the user&#39;s breathing may not be smooth. Recently, in order to solve the above-mentioned problems, a mask having a motor, a fan, and a filter has been developed. 
     An example of the mask may be found in Korean Utility Model Registration No. 20-0422942. The mask includes a filter for filtering foreign substances and a fan and a motor for forcibly flowing the air passing through the filter. 
     Another example of the mask, called a sports mask, may be found in Japanese Patent Laid-Open No. 2016-087376. The mask is provided with a fan for forcibly flowing the filtered air in front of the user&#39;s nose and mouth, and a hinge is further provided in the center of the mask to fold the mask. 
     SUMMARY 
     One aspect is to provide a mask device that may be changed in size to facilitate storage. 
     Another aspect is to provide a mask device which may prevent components of the mask device from being lost upon separation to change in size. 
     Another aspect is to provide a mask device which may be easy to perform maintenance work. 
     Another aspect is to provide a mask device capable of preventing contamination of one surface of a mask device on which a user&#39;s nose and mouth may be located. 
     Another aspect is to provide a mask device in which filtered air may be supplied to the user in large quantities. 
     The present disclosure describes a mask device that includes a mask body including a front cover to form an outer appearance of the mask body, a frame coupled to the front cover, the frame located in front of a user&#39;s nose and mouth when the mask device is worn by the user, and a flow path between the front cover and the frame. A first air cleaner is disposed on one side of the mask body and a second air cleaner is disposed on another side of the mask body, and a first fixing part couples the first air cleaner to the mask body and a second fixing part couples the second air cleaner to the mask body. The first air cleaner is movable with respect to the first fixing part to move towards the frame and the second air cleaner is movable with respect to the second fixing part to move towards the frame. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a left side perspective view of a mask device according to a first embodiment of the present invention. 
         FIG. 2  is a right side perspective view of the mask device according to the first embodiment of the present invention. 
         FIG. 3  is a rear side perspective view of the mask device according to the first embodiment of the present invention. 
         FIG. 4  is a frontal exploded view of the mask device according to the first embodiment of the present invention. 
         FIG. 5  is a rear exploded view of the mask body according to the first embodiment of the present invention. 
         FIGS. 6A and 6B  are views showing a packing according to the first embodiment of the present invention. 
         FIG. 7  is an exploded view of a first air cleaner according to the first embodiment of the present invention. 
         FIG. 8  is an exploded view of a second air cleaner according to the first embodiment of the present invention. 
         FIG. 9  is a view showing the first air cleaner fixed to a first fixing part according to the first embodiment of the present invention. 
         FIG. 10  is a view showing the second air cleaner fixed to a second fixing part according to the first embodiment of the present invention. 
         FIG. 11  is a view showing a folding state of the mask device according to the first embodiment of the present invention. 
         FIG. 12  is a cross-sectional view showing a state in which a mask body and an air cleaner are coupled according to the first embodiment of the present invention. 
         FIG. 13  is a cross-sectional view showing a state in which a mask body and an air cleaner are separated according to the first embodiment of the present invention. 
         FIG. 14  is a view showing a folded state of the mask device according to the first embodiment of the present invention. 
         FIG. 15  is a view showing a first catching part according to the first embodiment of the present invention. 
         FIG. 16  is a view showing a second catching part according to the first embodiment of the present invention. 
         FIGS. 17 and 18  are views showing an air flow flowing in the mask device according to the first embodiment of the present invention. 
         FIG. 19  is a view showing a locking portion of the mask device according to a second embodiment of the present invention. 
         FIG. 20  is a view showing a mask device according to a third embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to the components of the drawings, it should be noted that the same reference numerals may be used even though they are shown in different drawings. In addition, in describing the embodiments of the present invention, when it is determined that a detailed description of the well-known configuration or function interferes with the understanding of the embodiments of the present invention, the detailed description thereof may be omitted. 
     In addition, in describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being “connected”, “coupled” or “connected” to another component, it should be understood that the component may be directly connected or connected to that other component, but having other components there between. 
       FIG. 1  is a left side perspective view of a mask device according to a first embodiment of the present invention,  FIG. 2  is a right side perspective view of the mask device according to the first embodiment of the present invention,  FIG. 3  is a rear side perspective view of the mask device according to the first embodiment of the present invention, and  FIG. 4  is a frontal exploded view of the mask device according the first embodiment of the present invention. 
     Referring to  FIGS. 1 to 4 , the mask device  1  according to the embodiment may include a mask body  10 . The mask body  10  may be in close contact with a face of a user. When the mask body  10  is in close contact with the user&#39;s face, the mask body  10  may cover or wrap around the user&#39;s mouth and nose. 
     The mask body  10  may include a frame  11  and a front cover  12 . The frame  11  and the front cover  12  may be detachably coupled to each other. The frame  11  may be located in front of the user&#39;s nose and mouth, and may define a breathing space for receiving filtered air between the frame  11  and the user&#39;s nose and mouth. The front cover  12  may be positioned in a direction toward the outside environment and may form an outer appearance of the mask body  10 . A flow path through which air is supplied to the breathing space passes may be formed between the front cover  12  and the frame  11 . Air passing through the flow path formed between the front cover  12  and the frame  11  may enter the breathing space. In the present embodiment, the frame  11  may be referred to as a rear cover corresponding to the front cover  12 . In addition, when the front cover  12  is referred to as one side cover, first cover, front side, one side, etc., the frame  11  may be referred to as the other side cover, the second cover, the rear side, the other side, etc. 
     The frame  11  may include an inlet  111   a  and  111   b , and an outlet  112   a  and  112   b . The inlet  111   a  and  112   b  may be an opening that supplies air filtered from a first air cleaner  20  and a second air cleaner  40  in the direction toward the user&#39;s nose and mouth. The outlet  112   a  and  112   b  may be an opening for discharging air discharged from the user&#39;s nose and mouth to the outside environment. The inlet  111   a  and  111   b  may be located in front of the user&#39;s nose and the outlet  112   a  and  112   b  may be located in front of the user&#39;s mouth. The inlet  111   a  and  111   b  may be formed with an opening larger than the outlet  112   a  and  112   b  to facilitate the inflow of filtered air. When the inlet  111   a  and  111   b  is located in front of the user&#39;s nose, the filtered air may be quickly supplied to the user&#39;s nose. When the outlet  112   a  and  112   b  is located in front of the user&#39;s mouth, the air discharged from the user&#39;s mouth and the air discharged from the user&#39;s nose may be quickly discharged through the outlet  112   a  and  112   b . The air flowing from the mask body  10  toward the inlet  111   a  and  111   b , and the air discharged from the outlet  112   a  and  112   b  to the outside environment may flow in a state separated from each other vertically in the breathing space. Further description of the mask body  10  will be described with respect to  FIG. 4 . 
     The mask body  10  may include a first fixing part  13  and a second fixing part  14 . The first fixing part  13  and the second fixing part  14  may allow the first air cleaner  20  and the second air cleaner  40  to be fixed to the mask body  10 . In the present embodiment, the first fixing part  13  may be disposed on one side of the mask body  10 , and the second fixing part  14  may be disposed on the other side of the mask body  10 . The one side of the mask body  10  may be defined as a left end of the mask device  1  and the other side of the mask body  10  may be defined as the right end of the mask device  1 . 
     The first fixing part  13  and the second fixing part  14  may be fixed between the front cover  12  and the frame  11 . When the front cover  12  and the frame  11  are coupled to each other, insertion space may be formed at the left and right ends of the mask body  10  in which the first fixing part  13  and the second fixing part  14  may be inserted and fixed. The first fixing part  13  may be inserted into and fixed to the insertion space formed at the left end of the mask body. The second fixing part  14  may be inserted into and fixed to the insertion space formed at the right end of the mask body  10 . The insertion space formed between the frame  11  and the front cover  12  may be referred to as a fixing recess  129   a  and  129   b  (see  FIG. 5 ). Further description of the first fixing part  13  and the second fixing part  14  will be provided with respect to  FIGS. 9 and 10 . 
     The mask body  10  may include a packing  15 . The packing  15  may be coupled to the frame  11 . The packing  15  may be interposed between the frame  11  and the user&#39;s face when the mask body  10  is worn by the user. The packing  15  may be made of a material that may deform in shape corresponding to the user&#39;s face when the mask body  10  makes contact with the user&#39;s face. The packing  15  may be detachably mounted to the frame  11 . For example, the packing  15  may be mounted on the frame  11  or attached to one side of the frame  11 . The packing  15  may prevent a gap between the frame  11  and the user&#39;s face. Further description of the packing  15  will be provided with respect to  FIGS. 6A and 6B . 
     The mask device  1  may include the first air cleaner  20  and the second air cleaner  40 . The first air cleaner  20  and the second air cleaner  40  may be disposed at both sides of the mask body  10 , respectively. In the present embodiment, the first air cleaner  20  may be disposed at the left end of the mask body  10 , and the second air cleaner  40  may be disposed at the right end of the mask body  10 . 
     The first air cleaner  20  and the second air cleaner  40  may be detachably mounted to the first fixing part  13  and the second fixing part  14 . The first air cleaner  20  and the second air cleaner  40  may be movably coupled to the first fixing part  13  and the second fixing part  14 . That is, the first air cleaner  20  and the second air cleaner  40  may be moved in the direction toward the frame  11  on both sides of the mask body  10 . For example, the first air cleaner  20  may be folded with respect to the first fixing part  13 , and the second air cleaner  40  may be folded with respect to the second fixing part  14 . In the present embodiment, the first air cleaner  20  and the second air cleaner  40  are described as being folded with respect to the first fixing part  13  and the second fixing part  14 , however they may be rotatable. 
     When the first air cleaner  20  and the second air cleaner  40  are folded, the mask device  1  may be easily stored. When the first air cleaner  20  and the second air cleaner  40  are folded in the direction toward the frame  11  at both ends of the mask body  10 , the breathing space of the frame  11  may be shielded. When the breathing space of the frame  11  is shielded by the first air cleaner  20  and the second air cleaner  40 , foreign matter from the outside environment may be prevented from being attached to the surface of the frame  11  defining a surface of the breathing space. 
     The first air cleaner  20  and the second air cleaner  40  may suck air in from the outside environment and filter the sucked in air. The filtered air may flow to the inside of the mask body  10  and through the inlet  111   a  and  111   b  to be supplied to the nose and mouth of the user. Since the filtered air is supplied to the user through each of the first air cleaner  20  and the second air cleaner  40 , the flow rate of the filtered air may be increased, and a large amount of filtered air may be supplied to the user. This may help the user to breathe smoothly. 
     The first air cleaner  20  includes a first cleaner body  21  and a first cleaner cover  22 , and the second air cleaner  40  includes a second cleaner body  41  and a second cleaner cover  42 . The first and second cleaner bodies  21  and  41  and the first and second cleaner covers  22  and  42  may be detachably coupled to each other. When the first and second cleaner covers  22  and  42  are separated from the first and second cleaner bodies  21  and  41 , the insides of the first and second cleaner bodies  21  and  41  may be exposed to the outside. 
     The first and second cleaner bodies  21  and  41  may have an internal space in which a plurality of components may be accommodated. The internal spaces of the first and second cleaner bodies  21  and  41  may be shielded by the first and second cleaner covers  22  and  42 . First and second fan modules  24  and  44  (see  FIGS. 7 and 8 ) and first and second filter modules  25  and  45  may be disposed in the first and second cleaner bodies  21  and  41 . The first and second fan modules  24  and  44  may generate suction force for sucking in outside air. The first and second filter modules  25  and  45  may filter foreign matter from the sucked in air. The first and second filter modules  25  and  45  may be located upstream of the first and second fan modules  24  and  44  based on the flow direction of air. Alternatively, the first and second filter modules  25  and  45  may be located downstream of the first and second fan modules  24  and  44  based on the flow direction of air. 
     A battery  26  may be disposed inside the first cleaner body  21 . The space where the first fan module  24  and the first filter module  25  are disposed and the space where the battery  26  is disposed may be formed in the first cleaner body  21 . When the space in which the first fan module  24  and the first filter module  25  are disposed and the space in which the battery  26  is disposed are separated, it may be possible to limit the mixing of air in different spaces. The battery  26  may supply power for operating at least one of the first air cleaner  20  and the second air cleaner  40 . The battery  26  may be coupled to at least one of the first air cleaner  20  and the second air cleaner  40  by an electric wire  19  (see  FIG. 14 ). 
     A circuit board  46  (see  FIG. 8 ) may be positioned inside the second cleaner body  41 . The space where the second fan module  44  and the second filter module  45  are disposed and the space where the circuit board  46  is disposed may be formed in the second cleaner body  41 . When the space in which the second fan module  44  and the second filter module  45  are disposed and the space in which the circuit board  46  is disposed are separated, it may be possible to limit the mixing of air in different spaces. The circuit board  46  may control the operation of at least one of the first air cleaner  20  and the second air cleaner  40 . The circuit board  46  may be connected to at least one of the first air cleaner  20  and the second air cleaner  40  by the electric wire  19 . On the other hand, the circuit board  46  may be provided in plurality. The plurality of circuit boards  46  may include a first circuit board for controlling the first air cleaner  20  and a second circuit board for controlling the second air cleaner  40 . 
     When the battery  26  is disposed in any one of the first air cleaner  20  and the second air cleaner  40 , the circuit board  46  may be disposed in the other one of the first air cleaner  20  and the second air cleaner  40 . In other words, the battery  26  and the circuit board  46  balancing the weight of the battery  26  may be disposed inside different air cleaners to balance the weight of the mask device  10 . 
     The first and second cleaner covers  22  and  42  may include first and second suction openings  221  and  421 . The first and second suction openings  221  and  421  may be formed with a plurality of holes. A portion of the holes of the first and second suction openings  221  and  421  may communicate between the outside environment and the space in which the first and second fan modules  24  and  44  and the first and second filter modules  25  and  45  are disposed, respectively. A remaining portion of the holes of the first and second suction openings  221  and  421  may communicate between the outside environment and a space in which the battery  26  and the circuit board  46  are disposed, respectively. Air passing through the portion of the holes of the first and second suction openings  221  and  421  is supplied to the nose and mouth of the user, and air passing through the remaining portion of the holes of the first and second suction openings  221  and  421  may cool the battery  26  and the circuit board  46 . 
     The first and second cleaner covers  22  and  42  may include first and second switches  222  and  422 . The first and second switches  222  and  422  may be operation switches for operating the first and second air cleaners  20  and  40 . For example, the first switch  222  may operate the first air cleaner  20 , and the second switch  422  may operate the second air cleaner  40 . Alternatively, the first switch  222  may operate the first and second air cleaners  20  and  40  together in which case, the second switch  422  may not be necessary. Alternatively, the second switch  422  may operate the first and second air cleaners  20  and  40  together in which case the first switch  222  may not be necessary. The output and operation of the first and second fan modules  24  and  44  may be controlled according to how long the first and second switches  222  and  422  are pressed or the number of times the first and second switches  222  and  422  are pressed. Further description of the first air cleaner  20  and the second air cleaner  40  will be provided with respect to  FIGS. 7 and 8 . 
     The mask device  1  may include a first separation preventing part  28  and a second separation preventing part  48 . The first separation prevention part  28  may connect the first fixing part  13  and the first cleaner body  21 . The second separation preventing part  48  may connect the second fixing part  14  and the second cleaner body  41 . The first separation preventing part  28  and the second separation preventing part  48  may have a predetermined length. The first separation preventing part  28  may prevent the first cleaner body  21  from being separated from the first fixing part  13  by a specified distance or less. The second separation preventing part  48  may prevent the second cleaner body  41  from being separated from the second fixing part  14  by a specified distance or less. 
     The first separation preventing part  28  may be provided in plurality, spaced apart from each other between the first fixing part  13  and the first cleaner body  21 . The second separation preventing part  48  may be provided in plurality, spaced apart from each other between the second fixing part  14  and the second cleaner body  41 . One end portions of the first and second separation preventing parts  28  and  48  may be fixed to the first and second fixing parts  13  and  14 , and the other end portions of the first and second separation preventing parts  28  and  48  may be respectively fixed to the first and second cleaner bodies  21  and  41 . The first and second cleaner bodies  21  and  41  may move with respect to the first and second fixing parts  13  and  14  by the specified distance or less set by the first and second separation preventing parts  28  and  48 . 
     The first separation prevention part  28  may be separated from at least one of the first fixing part  13  and the first cleaner body  21 . The second separation preventing part  48  may be separated from at least one of the second fixing part  14  and the second cleaner body  41 . When the first and second separation prevention parts  28  and  48  are separated from at least one of the first and second fixing parts  13  and  14  and the first and second cleaner bodies  21  and  41 , the first and second air cleaners  20  and  40  may be separated from the mask body  10 . When the first and second air cleaners  20  and  40  are separated from the mask body  10 , first and second catcher parts  30  and  50  that are attached to the mask body  10  by the first and second air cleaners  20  and  40  may be detached. Thus, the first and second air cleaners  20  and  40  including the first and second catching parts  30  and  50  may be detachably mounted to the mask body  10  by the first and second separation preventing parts  28  and  48 . Further descriptions of the first separation preventing part  28  and the second separation preventing part  48  will be described with respect to  FIGS. 9 and 10 . 
     The mask device  1  may include the first catching part  30  and the second catching part  50 . The first catching part  30  and the second catching part  50  may be mounted to the first air cleaner  20  and the second air cleaner  40 , respectively. The first catching part  30  may be mounted on the first air cleaner  20 , and the second catching part  50  may be mounted on the second air cleaner  40 . The first air cleaner  20  may be mounted on one side of the first catching part  30 , and the second air cleaner  40  may be mounted on one side of the second catching part  50 . The first catching part  30  may be configured to mount the first air cleaner  20  on the inside. The second catching part  50  may be configured to mount the second air cleaner  40  on the inside. The first catching part  30  may be fixed to the user&#39;s left ear, and the second catching part  50  may be fixed to the user&#39;s right ear. The mask body  10  may be fixed to the user&#39;s face by the first catching part  30  and the second catching part  50 . 
     The first catching part  30  may include a first hanger body  31 . The second catching part  50  may include a second hanger body  51 . The first hanger body  31  and the second hanger body  51  may be formed to be fixed to the user&#39;s ears. For example, the first and second hanger bodies  31  and  51  may be provided in a string or ring shape to be fixed to the user&#39;s ears. One side of the first and second hanger body  31  and  51  may be fixed to the first and second air cleaner  20  and  40 , the other side of the first and second hanger body  31  and  51  may be fixed to the user&#39;s ears. Between the first and second air cleaners  20  and  40  and the ears of the user, the first and second hanger bodies  31  and  51  may stretch or shrink in the longitudinal direction so that the mask body  10  may be fixed to the user&#39;s face. 
     A portion of the first air cleaner  20  may be locked to the first hanger body  31 , and a portion of the second air cleaner  40  may be locked to the second hanger body  51 . The first and second hanger bodies  31  and  51  and the first and second air cleaners  20  and  40  may be detachably coupled to each other. The first hanger body  31  may include a first handle  314  and a first contact part  32 . The second hanger body  51  may include a second handle  514  and a second contact part  52 . The first and second handles  314  and  514  may be parts that the user grasps when the first and second hanger bodies  31  and  51  are mounted on the user&#39;s ears. The first and second handles  314  and  514  may protrude from the other side of the first and second hanger bodies  31  and  51 . The first and second contact parts  32  and  52  may be parts that contact the user&#39;s ears when the first and second hanger bodies  31  and  51  are mounted on the user&#39;s ears. The first and second contact parts  32  and  52  may be disposed on inner surfaces of the first and second hanger bodies  31  and  51 . The load of the mask device  1  applied to the ears of the user may be distributed by the first and second contact parts  32  and  52 . Further description of the first catching part  30  and the second catching part  50  will be described with respect to  FIGS. 15 and 16 . 
       FIG. 5  is a rear exploded view of the mask body according to the first embodiment of the present invention. 
     Referring to  FIG. 5 , the mask body  10  according to the embodiment may combine the frame  11  and the front cover  12  to form the body. The frame  11  and the front cover  12  may be detachably coupled to each other. 
     Flow passages  124   a ,  124   b  and  124   c  through which air passes may be disposed between the frame  11  and the front cover  12 . The flow passages may include a flow passage for supplying filtered air to the user and a flow passage for discharging air to the outside environment. A partition may be formed between the frame  11  and the front cover  12  to form a flow path. The partition may be disposed on at least one of the frame  11  and the front cover  12 . When the front cover  12  is coupled to the frame  11 , the partition may define a flow passage between the front cover  12  and the frame  11 . 
     The partition may include a first partition plate  121  and a second partition plate  122 . The first partition plate  121  and the second partition plate  122  may start from one of the front cover  12  and the frame  11  and protrude to the other of the front cover  12  and the frame  11 . For example, the first partition plate  121  and the second partition plate  122  may protrude from one surface of the front cover  12  facing the frame  11  toward the frame  11 . The first partition plate  121  and the second partition plate  122  may be in contact with the frame  11  when the frame  11  and the front cover  12  are coupled to each other. The first partition plate  121  and the second partition plate  122  may be spaced apart from each other at regular intervals. The distance between the first partition plate  121  and the second partition plate  122  may define the flow cross-sectional areas of the flow passages  124   a  and  124   b . The distance between the first partition plate  121  and the second partition plate  122  may be adjusted in consideration of the flow rate of air passing through the flow passages  124   a  and  124   b . When the flow cross-sectional area of the flow passages  124   a  and  124   b  is kept constant, a decrease in the flow rate of air passing through the flow passages  124   a  and  124   b  may be prevented. 
     The second partition plate  122  may partition a space between the front cover  12  and the frame  11  into an upper space and a lower space. A flow passage for supplying air to the user&#39;s nose and mouth may be located in the upper space. A flow passage for discharging air discharged to the outside environment may be located in the lower space. 
     In the present embodiment, the first compartment plate  121  may be disposed above the second compartment plate  122 . A first flow passage  124   a  and a second flow passage  124   b  may be formed between the first partition plate  121  and the second partition plate  122  to supply filtered air to the user. The first flow passage  124   a  and the second flow passage  124   b  may be passages through which air flowing toward the inlet  111   a  and  111   b  passes. 
     The first partition plate  121  may divide the upper space into a space in which the first flow passage  124   a  and the second flow passage  124   b  are formed and a space in which no flow passage is formed. A plurality of components may be disposed in the space where no flow passage is formed. For example, the plurality of components may include a fragrance module for supplying a fragrance, an ionizer for sterilizing air, and the like. 
     For example, the fragrance module may be provided on any one of the front cover  12  and the frame  11 . The fragrance module may provide fragrance to air introduced into a user&#39;s nose and mouth through at least one of the first flow passage  124   a  and the second flow passage  124   b . A porous part may be formed in the first partition plate  121  so that the fragrance of the fragrance module may be supplied to at least one of the first flow passage  124   a  and the second flow passage  124   b . In addition, the porous part may be formed in at least one of a first inflow guide  123   a  and a second inflow guide  123   b . The fragrance module may be removed and be replaced when the front cover  12  and the frame  11  are separated. 
     A third flow passage  124   c  may be formed in the lower space. The third flow passage  124   c  may be a passage through which air discharged through the outlet  112   a  and  112   b  passes. That is, the second partition plate  122  may partition the first flow passage  124   a , the flow second passage  124   b , and the third flow passage  124   c.    
     The first partition plate  121  and the second partition plate  122  may perform a function of a support rib supporting the frame  11  and the front cover  12 . The first partition plate  121  and the second partition plate  122  may function as reinforcing ribs to reinforce strength of at least one of the front cover  12  and the frame  11 . 
     In the present embodiment, the second partition plate  122  may partition into the upper space and the lower space, and may be referred to as an “up and down partition plate”. The first partition plate  121  may be a part of the first flow passage  124   a  and the second flow passage  124   b  and may perform a function for reinforcing strength. The first partition plate  121  may be referred to as a “reinforcement partition plate”. For example, in configuring the partition of the upper space, if the first partition plate  121  is not provided, the flow rate of air that passes through the upper space may be increased. 
     The first inflow guide  123   a  and the second inflow guide  123   b  may be provided between the first partition plate  121  and the second partition plate  122 . The first inflow guide  123   a  and the second inflow guide  123   b  may connect the first partition plate  121  and the second partition plate  122 . The first inflow guide  123   a  and the second inflow guide  123   b  may be formed from any one of the first and second partition plates  121  and  122  and may extend toward the other one of the first and second partition plates  121  and  122 . An extension length of the first inflow guide  123   a  and the second inflow guide  123   b  may correspond to the separation distance between the first compartment plate  121  and the second compartment plate  122 . The first inflow guide  123   a  and the second inflow guide  123   b  may extend in a direction toward the front cover  12  and the frame  11 , and may extend to the front cover  12  and the frame  11 . 
     The first inflow guide  123   a  and the second inflow guide  123   b  may fill the space between the first partition plate  121  and the second partition plate  122  with the first flow passage  124   a  and the second flow passage  124   b . The first inflow guide  123   a  and the second inflow guide  123   b  may be spaced apart from each other in both directions. For example, the first inflow guide  123   a  may be located in the left direction of the user&#39;s nose. The second inflow guide  123   b  may be located in the right direction of the user&#39;s nose. Thus, a user&#39;s nose may be located between the first inflow guide  123   a  and the second inflow guide  123   b.    
     The first inlet guide  123   a  may guide an air flow direction such that air supplied from the first air cleaner  20  may flow to the first inlet  111   a  among the inlet  111   a  and  111   b . The second inflow guide  123   b  may guide the air flow direction such that the air supplied from the second air cleaner  40  flows to the second inlet  111   b  of the inlet  111   a  and  111   b . The first inflow guide  123   a  and the second inflow guide  123   b  may be formed to be inclined such that air flows in a direction toward the first and second inlets  111   a  and  111   b . For example, the first inflow guide  123   a  and the second inflow guide  123   b  may be inclined in a direction from the front cover  12  toward the frame  11 . When the front cover  12  and the frame  11  are coupled to each other, the first inflow guide  123   a  and the second inflow guide  123   b  may connect the first flow passage  124   a  and the second flow passage  124   b . In the present embodiment, the first inlet  111   a  may be located at the left side of the user&#39;s nose, and the second inlet  111   b  may be located at the right side of the user&#39;s nose. 
     Air passing through the outlet  112   a  and  112   b  may be introduced into the third passage  124   c . The outlet  112   a  and  112   b  may include a first outlet  112   a  disposed at the left side and a second outlet  112   b  disposed at the right side with respect to the center of the mask body  10 . The first outlet  112   a  may be spaced apart from the user&#39;s nose in the direction toward the user&#39;s mouth. The second outlet  112   b  may be spaced apart from the user&#39;s nose in the direction toward the user&#39;s mouth. The air discharged from the user&#39;s nose and mouth may pass through the first and second outlet  112   a  and  112   b  and then enter the third passage  124   c.    
     The mask body  10  may be provided with a discharge port  128   a  and  128   b  for discharging the air introduced into the third passage  124   c  to the external environment. The discharge port  128   a  and  128   b  may include a first discharge port  128   a  disposed on the left side and a second discharge port  128   b  disposed on the right side with respect to the center of the mask body  10 . Air discharged from the first outlet  112   a  may be introduced into the first discharge port  128   a . Air discharged from the second outlet  112   b  may be introduced into the second discharge port  128   b . The discharge port  128   a  and  128   b  may be formed in any one of the front cover  12  and the frame  11 . In the present embodiment, the discharge port  128   a  and  128   b  is described as being formed in the front cover  12 . The discharge port  128   a  and  128   b  may be formed at the lower portion of the front cover  12 . When the discharge port  128   a  and  128   b  is formed at the lower portion of the front cover  12 , it may be possible to minimize the mixing of the air discharged from the mask device  1  with the air sucked into the mask device  1 . In addition, the noise of the air being discharged from the discharge port  128   a  and  128   b  may be limited. It should be noted that the position of the discharge port  128   a  and  128   b  may be variously changed. 
     One of the discharge port  128   a  and  128   b  and the outlet  112   a  and  112   b  may be provided with a check valve  118 . The check valve  118  may prevent discharged air from flowing back into the mask device  1 . The check valve  118  may prevent unfiltered air from the outside environment from entering the user&#39;s nose and mouth through any one of the discharge port  128   a  and  128   b  and the outlet  112   a  and  112   b . The check valve  118  may be closed when the user inhales the filtered air to prevent the outside air from flowing into any one of the discharge port  128   a  and  128   b  and the outlet  112   a  and  112   b . The check valve  118  may be opened to discharge the air exhaled by the user to be discharged to the outside environment. The check valve  118  may be disposed on at least one side of the discharge port  128   a  and  128   b  and the outlet  112   a  and  112   b , and may open or close at least one of the discharge port  128   a  and  128   b  and the outlet  112   a  and  112   b.    
     The front cover  12  may include an upper fastener  126  and a lower fastener  127 . The upper fastener  126  and the lower fastener  127  may be provided in plural. The upper fastener  126  may be located at a upper portion of the front cover  12 . A plurality of upper fasteners  126  may be spaced apart from each other in both directions of the front cover  12 . The lower fastener  127  may be located at the lower portion of the front cover  12 . A plurality of lower fasteners  127  may be spaced apart from each other in both directions of the front cover  12 . The upper and lower portions of the front cover  12  may further include support ribs on which the upper fastener  126  and the lower fastener  127  are located. The support ribs may protrude from the upper and lower portions of the front cover  12 . The upper fastener  126  may be positioned to face an upper fixture  113 . The lower fastener  127  may be positioned to face a lower fixture  114 . 
     The frame  11  may include the upper fixture  113  and a lower fixture  114 . The upper fixture  113  and the lower fixture  114  may be provided in plural. The upper fixture  113  may be disposed at the upper portion of the frame  11 . A plurality of upper fixtures  113  may be spaced apart from each other in both directions. The lower fixture  114  may be disposed at the lower portion of the frame  11 . A plurality of lower fixtures  114  may be spaced apart from each other in both directions. The upper fixture  113  may be disposed at a position corresponding to the upper fastener  126 , and the lower fixture  114  may be disposed at a position corresponding to the lower fastener  127 . Alternatively, the upper fastener  126  and the lower fastener  127  may be disposed on the frame  11 , and the upper fixture  113  and the lower fixture  114  may be disposed on the front cover  12 . 
     In the present embodiment, the upper fixture  113 , the lower fixture  114 , the upper fastener  126 , and the lower fastener  127  may be provided as a magnet member. Alternatively, the upper fastener  126  and the lower fastener  127  may be provided as a fastening member, and the upper fixture  113  and the lower fixture  114  may be provided as fastening grooves to which the fastening member is fastened. When the upper fastener  126  is coupled to the upper fixture  113 , the upper portion of the frame  11  and the upper portion of the front cover  12  may be fixed to each other. When the lower fastener  127  is coupled to the lower fixture  114 , the lower portion of the frame  11  and the lower portion of the front cover  12  may be fixed to each other. 
     The mask body  10  may include a first fixing recess  129   a  and a second fixing recess  129   b . The first fixing part  13  may be fixed to the first fixing recess  129   a , and the second fixing part  14  may be fixed to the second fixing recess  129   b . The first fixing recess  129   a  and the second fixing recess  129   b  may be disposed between the front cover  12  and the frame  11 . A portion of the first fixing recess  129   a  and the second fixing recess  129   b  may be defined by the front cover  12 , and the remaining portion of the first fixing recess  129   a  and the second fixing recess  129   b  may be defined by the frame  11 . The first fixing recess  129   a  and the second fixing recess  129   b  may be disposed at both sides of the mask body  10 , respectively. 
     When the front cover  12  and the frame  11  are coupled to each other, the end portions of the first fixing part  13  and the second fixing part  14  may be fixed between the front cover  12  and the frame  11 . The first fixing recess  129   a  may be disposed at the left end of the mask body  10 . The second fixing recess  129   b  may be disposed at the right end of the mask body  10 . The first fixing recess  129   a  and the second fixing recess  129  provided for fixing the first fixing part  13  and the second fixing part  14  to the mask body  10 . 
     A plurality of fixing protrusions  119  may provide for fixing the first fixing part  13  and the second fixing part  14  to the mask body  10 . The plurality of fixing protrusions  119  may be disposed on at least one of the front cover  12  and the frame  11 . In the present embodiment, the plurality of fixing protrusions  119  may be provided in the frame  11 . The plurality of fixing protrusions  119  may be disposed at both ends of the frame  11 , respectively. The plurality of fixing protrusions  119  may be spaced apart from each other. A plurality of fixing protrusion insertion holes into which the plurality of fixing protrusion  119  may be inserted may be formed in the first fixing part  13  and the second fixing part  14 . The plurality of fixing protrusions  119  are inserted into the respective plurality of fixing protrusion insertion holes so that the first fixing part  13  and the second fixing part  14  are firmly fixed into the first fixing recess  129   a  and the second fixing recess  129   b.    
       FIGS. 6A and 6B  are views showing a packing according to the first embodiment of the present invention. 
     Referring to  FIGS. 6A and 6B , the mask body  10  according to the embodiment may include a packing  15   a  and  15   b . The packing  15   a  and  15   b  may be detachably coupled to the mask body  10 . For example, the packing  15   a  and  15   b  may be detachably coupled to the frame  11 . The packing  15   a  and  15   b  may be disposed between the user&#39;s face and the mask body  10 . The packing  15   a  and  15   b  may disperse the pressure applied to the user&#39;s face when the mask body  10  is in close contact with the user&#39;s face. The packing  15   a  and  15   b  may seal a gap that may form between the user&#39;s face and the mask body  10  when the mask body  10  is in close contact with the user&#39;s face. In the present embodiment, the packing  15   a  and  15   b  may be formed in a configuration shown in  FIG. 6A  and  FIG. 6B .  FIG. 6A  shows an embodiment of the first packing  15   a  and  FIG. 6B  shows an embodiment of the second packing  15   b.    
     Referring to  FIG. 6A , the first packing  15   a  may include a packing body  151  forming a body. The packing body  151  may be mounted at the corner or the outer circumferential surface of the frame  11 . The packing body  151  may be formed to correspond to an edge or outer circumferential surface of the frame  11 . The first packing  15   a  may be made of a material that is easily deformed and may be deformed when the first packing  15   a  is in close contact with the user&#39;s face. For example, the first packing  15   a  may be made of silicon, rubber, or the like. The packing body  151  may be formed to be hollow inside. For example, the packing body  151  may be formed in a ring or ring shape being hollow inside. The frame  11  may be disposed inside the hollow portion of the packing body  151 . The packing body  151  may be formed to have a constant first thickness t 1 . In this case, the first thickness t 1  may be greater than the thickness of the frame  11 . The packing body  151  having the first thickness t 1  may be deformed in thickness between the user&#39;s face and the frame  11 . 
     The packing body  151  may include a frame insertion groove  152 . The frame insertion groove  152  may be understood as a portion in which an edge or an outer circumferential surface of the frame  11  is inserted and fixed. The frame insertion groove  152  may be formed by recessing an inner portion of the packing body  151 . For example, the frame insertion groove  152  may be recessed in a direction from the inner surface of the packing body  151  toward the outer surface of the packing body  151 . 
     When the mask body  10  is in close contact with the user&#39;s face, the packing body  151  may contact the user&#39;s face rather than the frame  11 . In the state of being in contact with the user&#39;s face, the packing body  151  may deform to close the gap and bring the mask body  10  into close contact with the user&#39;s face. 
     Referring to  FIG. 6B , the second packing  15   b  may include a packing body  151  forming a body. The packing body  151  may be formed to have a constant first thickness t 1  with a portion of the packing body  151  being formed to have a second thickness t 2 . The second thickness t 2  may be larger than the first thickness t 1 . The portion of the packing body  151  having the second thickness t 2  may be located in front of the nose of the user, so that a gap that may be formed between the user&#39;s nose and the frame  11  may be more closely sealed. 
     For example, the user&#39;s nose and the frame  11  that is not sealed by the packing body  151  having the first thickness t 1  may have a gap between the user&#39;s nose and the packing body  151 , but having the second thickness t 2  may seal the gap. In addition, a portion of the packing body  151  having the second thickness t 2  may be seated on a user&#39;s nose. When a part of the packing body  151  having the second thickness t 2  is seated on the user&#39;s nose, a supporting function of supporting the mask body  10  on the user&#39;s nose may be performed. Thus, a part of the packing body  151  having the second thickness t 2  may be considered as a nose support  16 . 
     The packing body  151  may include a frame insertion groove  152 . The frame insertion groove  152  may be a part into which the frame  11  is inserted and fixed to the packing. 
     In the present embodiment, the frame  11  is described as being inserted into and fixed to the frame insertion groove  152  of the packing, but the packing is attached to one surface of the frame  11 . Or combination of structures are also possible. The packing may be detachably coupled to the edge or the outer circumferential surface of the frame  11  to be in close contact with the user&#39;s face. 
       FIG. 7  is an exploded view of the first air cleaner according to the first embodiment of the present invention, and  FIG. 8  is an exploded view of the second air cleaner according to the first embodiment of the present invention. 
     Referring to  FIGS. 7 and 8 , the mask device  1  according to the embodiment may include the first air cleaner  20  and the second air cleaner  40 . The first air cleaner  20  and the second air cleaner  40  may suck in outside air from both sides of the mask body  10 . The air sucked into the first air cleaner  20  and the second air cleaner  40  may be filtered inside the first air cleaner  20  and the second air cleaner  40 . Filtered air may flow into the mask body  10 . The filtered air may be supplied to the user&#39;s nose and mouth after passing through the first flow passage  124   a  and the second flow passage  124   b  of the mask body  10 . The first air cleaner  20  and the second air cleaner  40  may be operated together. Alternatively, the first air cleaner  20  and the second air cleaner  40  may be operated individually. 
     Hereinafter, the first air cleaner  20  and the second air cleaner  40  will be described in order. 
     Referring to  FIG. 7 , the first air cleaner  20  may include a first cleaner body  21 . The first cleaner body  21  may be deeply recessed in the interior, and a plurality of components may be stored in the recessed interior. For example, the first fan module  24 , the first filter module  25 , and the battery  26  may be stored in the first cleaner body  21 . In the present embodiment, the first cleaner body  21  may include a bottom face facing the user&#39;s face, a plurality of side surfaces bent from the bottom face, and an upper surface opened to insert a plurality of components. For example, the first cleaner body  21  may be formed in a container shape in which one surface thereof is opened. The first cleaner body  21  may form a body by a bottom surface, a first side surface  21   a , a second side surface  21   b , a third side surface  21   c , and a fourth side surface  21   d . Side surfaces of the first cleaner body  21  may include the first side surface  21   a , the fourth side surface  21   d  facing the first side surface  21   a , the second side surface  21   b  and the third side surface  21   c  coupling the first side surface  21   a  and the fourth side surface  21   d . The bottom surface couples one side of the side surfaces  21   a - 21   d . The upper surface facing the bottom surface may be opened. 
     The first cleaner body  21  may include a first protrusion  210 . The first protrusion  210  may protrude from one surface of the first cleaner body  21 . The first protrusion  210  may be located at the side of the first cleaner body  21 . In the present embodiment, the first protrusion  210  may be located on the first side surface  21   a . When the first cleaner body  21  is coupled to the first fixing part  13 , the first protrusion  210  limits the amount of insertion of a first duct  211  into the first fixing part  13 , and thus may perform as a stopper function. For example, the first protrusion  210  may be formed to have a rectangular cross section. When the first cleaner body  21  is coupled to the first fixing part  13 , the first protrusion  210  may be in contact with a portion of the first fixing part  13 . The first protrusion  210  and the first duct  211  of the first cleaner body  21  is first inserted into a first duct through hole  311  of the first catching part  30  (see  FIG. 4 ), and a part of the first catching part  30  contacts the first fixing part  13  with the first duct  211  being inserted into the first fixing part  13 . A portion of the first cleaner body  21  may be disposed between the hanger body  31  of the first catching part  30 . 
     The first cleaner body  21  may include the first duct  211 . The first duct  211  may be formed to protrude further from the first protrusion  210 . The first duct  211  may have a diameter smaller than the diameter of the first protrusion  210 . The first duct  211  may be inserted into the first fixing part  13  of the mask body  10 . The first duct  211  may couple the first cleaner body  21  and the mask body  10 . The first duct  211  may be an air passage for supplying the air filtered by the first air cleaner  20  to the mask body  10 . When the first duct  211  is inserted into the first fixing part  13  and the first protrusion  210  contacts a part of the first fixing part  13 , the first air cleaner  20  may be fixed to the mask body  10 . When the first duct  211  is separated from the first fixing part  13 , the first air cleaner  20  and the mask body  10  may be separated from each other. For example, the first duct  211  may be formed to have a rectangular cross section. When the first duct  211  is formed to have a rectangular cross section, binding between the first fixing part  13  and the first cleaner body  21  may be facilitated. 
     A first air flow hole  211   a  may be formed in the first duct  211  and the first protrusion  210 . The first air flow hole  211   a  may be formed by opening an interior of the first duct  211  and the first protrusion  210 . The first air flow hole  211   a  may pass through the first duct  211  and the first protrusion  210 . One side of the first air flow hole  211   a  may be in communication with a first air flow space  214  formed in the first cleaner body  21 . The other side of the first air flow hole  211   a  may communicate with the first flow passage  124   a  of the mask body  10 . The first cleaner body  21  and the mask body  10  may communicate with each other by the first air flow hole  211   a.    
     The first cleaner body  21  may include a first fixing hook  212 . The first fixing hook  212  may be formed at the first duct  211 . The first fixing hook  212  may be formed by cutting a portion of the first duct  211 . The first fixing hook  212  may elastically deform with respect to the first duct  211  when the first fixing hook  212  is being mounted or detached from the first fixing part  13 . When the first duct  211  is coupled to the first fixing part  13 , the first fixing hook  212  may be fixed to the first fixing part  13 . The first fixing hook  212  fixed to the first fixing part  13  may be released by a first fixing hook releasing part  133  (see  FIG. 4 ) formed at the first fixing part  13 . 
     The first cleaner body  21  may include a first wire tube  213 . The first wire tube  213  may protrude from the first cleaner body  21 . The first wire tube  213  may protrude from the side of the first cleaner body  21 . The first wire tube  213  may be disposed on the first side surface  21   a  of the first cleaner body  21 . The first wire tube  213  may be disposed at one side of the first duct  211 . The first wire tube  213  may be a passage through which the wire  19  passes. The first wire tube  213  may be an opening into which the first separation preventing part  28  may be inserted in one embodiment. The first wire tube  213  may provide communication between a first accommodation space  215  formed in the first cleaner body  21  and the third flow passage  124   c  formed in the mask body  10 . The first wire tube  213  may be inserted into a part of the first fixing part  13 . For example, the first wire tube  213  may be formed to have a circular or square cross section. 
     The first wire tube  213  may include a first wire through hole  213   a . The first wire through hole  213   a  may be formed by opening an interior of the first wire tube  213 . One side of the first wire through hole  213   a  may communicate with the first accommodation space  215 . The other side of the first wire through hole  213   a  may communicate with the third flow passage  124   c . A portion of the air passing through the third flow passage  124   c  may be introduced into the first accommodating space  215  by the first wire through hole  213   a . When the air flows into the first accommodation space  215 , a plurality of components stored in the first accommodation space  215  may be cooled. 
     The first cleaner body  21  may include a first compartment rib  216 . The first compartment rib  216  may be provided inside the first cleaner body  21 . The first compartment rib  216  may divide the internal space of the first cleaner body  21  into the first air flow space  214  and the first accommodation space  215 . The first compartment rib  216  may protrude from an inner surface of the first cleaner body  21 . For example, the first compartment rib  216  may be formed to protrude in a direction toward an upper surface opened from the bottom of the first cleaner body  21 . The first fan module  24  and the first filter module  25  may be accommodated in the first air flow space  214 , and air may pass therethrough. The first compartment rib  216  may define a shape of the first air flow space  214  to accommodate the first fan module  24  and the first filter module  25 . The first fan module  24  and the first filter module  25  may be mounted in the first air flow space  214 . The first accommodating space  215  may include the battery  26  or a plurality of components including the battery  26 . 
     The first cleaner body  21  may include the first fan module  24  and the first filter module  25 . The first fan module  24  and the first filter module  25  may be disposed in the first air flow space  214  formed by the first compartment rib  216 . The first fan module  24  may generate a suction force for sucking in outside air. The first filter module  25  may filter foreign matter from the outside air sucked in by the first fan module  24 . The first filter module  25  may be located upstream of the first fan module  24  based on the flow direction of air. The filtered air filtered by the first filter module  25  may flow through the first air flow hole  211   a  into the first flow passage  124   a . The first fan module  24  may include a fan and a motor, and the first filter module  25  may include various filters. 
     The first cleaner body  21  may include the battery  26 . The battery  26  may be disposed inside the first accommodation space  215 . The battery  26  may be disposed to be detachable from the first cleaner body  21 . The battery  26  may supply power to at least one of the first air cleaner  20  and the second air cleaner  40 . 
     The first cleaner body  21  may include a first locking hook  217 . The first locking hook  217  may be provided in plurality. The first locking hook  217  may allow the first catching part  30  and the first cleaner body  21  to be coupled to each other. The first locking hook  217  may protrude from the side of the first cleaner body  21 . The plurality of first locking hooks  217  may be located on the second side  21   b  and the third side  21   c  of the first cleaner body  21 . A portion of the first locking hook  217  protruding outward may be bent in a direction toward the first protrusion  210 . The first locking hook  217  may protrude outward from the second side surface  21   b  and the third side surface  21   c  and then be bent in a direction toward the first side surface  21   a . The first locking hook  217  may be fixed to the first catching part  30  by the bent portion of the first locking hook  217 , and separation of the first locking hook  217  from the first catching part  30  may be prevented. 
     The first cleaner body  21  may include a first opening  219 . The first opening  219  may be an opening through which a first separation preventing strap  281  of the first separation preventing part  28  passes. The first opening  219  may be located on the first side surface  21   a . The first opening  219  may be formed in a size corresponding to the first separation prevention strap  281 . For example, an opening of any one of the plurality of first openings  219  may be located near the first protrusion  210 , and the other opening may be located near the first wire tube  213 . The first wire tube  213  and the first protrusion  210  may be positioned between any one opening and the other opening. The first air cleaner  20  is easily folded with respect to the mask body  10  by the first separation preventing part  28  provided in the one opening and in the other opening. In the present embodiment, the first opening  219  positioned in the first cleaner body  21  may be referred to as the other side opening. 
     The first air cleaner  20  may include the first cleaner cover  22 . The first cleaner cover  22  may cover the first cleaner body  21 . The first cleaner cover  22  may be detachably mounted on the opened upper surface of the first cleaner body  21  by the first cover fixing part  207  and the first cover coupling part. When the first cleaner cover  22  is mounted to the first cleaner body  21 , the first cleaner cover  22  may contact the first compartment rib  216 . When the first cleaner cover  22  is mounted on the first cleaner body  21 , the inner space of the first cleaner body  21  may be partitioned into the first air flow space  214  and the first accommodation space  215 . 
     The first cleaner cover  22  may include the first suction opening  221 . The first suction opening  221  may be formed with a plurality of holes or may have a mesh shape at the first cleaner cover  22 . Some of the plurality of first suction openings  221  may communicate with the first air flow space  214 . Those first suction openings  221  may be located above the first air flow space  214 . The remaining of the plurality of first suction openings  221  may communicate the first accommodation space  215 . The remaining plurality of first suction openings  221  may be located above the first accommodation space  215 . Air passing through the some of the plurality of first suction holes  221  may be sucked into the first air flow space  214 . The first accommodation space  215  may be ventilated by the air flowing in or out through the remaining plurality of first suction openings  221 . Large foreign matter contained in the outside air may be filtered by the first suction opening  221 . 
     The first cleaner cover  22  may include a first switch  222 . The first switch  222  may be exposed on the outer side of the first cleaner cover  22 . The first switch  222  may an operation switch for operating the first air cleaner  20 . The first switch  222  may be provided as a power switch to turn on/off the first air cleaner  20 . The first switch  222  may be used as an operation switch for controlling the operation of the first air cleaner  20  according to the duration of the first switch  222  pressed, the number of times of the first switch  222  is pressed, etc. In the present embodiment, the first switch  222  shows as being one, however a plurality of switches may be provided as needed. The plurality of switches may also be referred to as a switch. 
     The first cleaner cover  22  may include a switch circuit board for driving the first switch  222 . The switch circuit board may be located at an inner surface of the first cleaner cover  22  corresponding to the first accommodation space  215 . When the first cleaner body  21  and the first cleaner cover  22  are coupled, the switch circuit board may be stored in the first accommodation space  215 . 
     Referring to  FIG. 8 , the second air cleaner  40  may include a second cleaner body  41 . The second cleaner body  41  may form a body of the second air cleaner  40 . The second cleaner body  41  may be deeply recessed inside, and a plurality of components may be stored in the recessed interior. For example, the second fan module  44 , the second filter module  45 , and the circuit board  46  may be stored in the second cleaner body  41 . In the present embodiment, the second cleaner body  41  may include a bottom facing the user&#39;s face, a plurality of side surfaces bent from the bottom, and an upper surface opened to insert a plurality of components. For example, the second cleaner body  41  may be formed in a container shape in which one surface thereof is opened. The second cleaner body  41  may form a body by a bottom surface, a first side surface  41   a , a second side surface  41   b , a third side surface  41   c , and a fourth side surface  41   d . Side surfaces of the second cleaner body  41  may include the first side surface  41   a , the fourth side surface  41   d  facing the first side surface  41   a , the second side surface  41   b  and the third side surface  41   c  coupling the first side surface  41   a  and the fourth side surface  41   d . The bottom surface couples one surface of the side surfaces  41   a - 41   d . The upper surface facing the bottom surface may be opened. 
     The second cleaner body  41  may include a second protrusion  410 . The second protrusion  410  may protrude from one surface of the second cleaner body  41 . The second protrusion  410  may be located at the side of the second cleaner body  41 . In the present embodiment, the second protrusion  410  may be located on the first side surface  41   a . When the second cleaner body  41  is coupled to the second fixing part  14 , the second protrusion  410  limits the amount of insertion of the second duct  411  inserted into the second fixing part  14 , and thus may perform as a stopper function. For example, the first protrusion  210  may be formed to have a rectangular cross section. When the second cleaner body  41  is coupled to the second fixing part  14 , the second protrusion  410  may be in contact with a portion of the second fixing part  14 . The second protrusion  410  and the second duct  411  of the second cleaner body  41  is first inserted into a second duct through hole  511  of the second catching part  50 , and a part of the second catching part  50  contacts the second fixing part  14  with the second duct  411  being inserted into the second fixing part  14 . A portion of the second cleaner body  41  may be disposed between the hanger body  31  of the second catching part  50 . 
     The second cleaner body  41  may include the second duct  411 . The second duct  411  may formed to protrude further from the second protrusion  410 . The second duct  411  may have a diameter smaller than the diameter of the second protrusion  410 . The second duct  411  may be inserted into the second fixing part  14  of the mask body  10 . The second duct  411  may couple the second cleaner body  41  and the mask body  10 . The second duct  411  may be an air passage for supplying air filtered by the second air cleaner  40  to the mask body  10 . When the second duct  411  is inserted into the second fixing part  14  and the second protrusion  410  contacts a part of the second fixing part  14 , the second air cleaner  40  may be fixed to the mask body  10 . When the second duct  411  is separated from the second fixing part  14 , the second air cleaner  40  and the mask body  10  may be separated from each other. For example, the second duct  411  may be formed to have a rectangular cross section. When the second duct  411  is formed to have a rectangular cross section, binding between the second fixing part  14  and the second cleaner body  41  may be facilitated. 
     A second air flow hole  411   a  may be formed in the second duct  411  and the second protrusion  410 . The second air flow hole  411   a  may be formed by opening an interior of the second duct  411  and the second protrusion  410 . The second air flow hole  411   a  may pass through the second duct  411  and the second protrusion  410 . One side of the second air flow hole  411   a  may be in communication with the second air flow space  414  formed in the second cleaner body  41 . The other side of the second air flow hole  411   a  may be in communication with the second flow passage  124   b  of the mask body  10 . The second cleaner body  41  and the mask body  10  may communicate with each other by the second air flow hole  411   a.    
     The second cleaner body  41  may include a second fixing hook  412 . The second fixing hook  412  may be formed in the second duct  411 . The second fixing hook  412  may be formed by cutting a portion of the second duct  411 . The second fixing hook  412  may elastically deform with respect to the second duct  411  when the second fixing hook  412  is mounted or detached from the second fixing part  14 . When the second duct  411  is connected to the second fixing portion  14 , the second fixing hook  412  may be fixed to the second fixing part  14 . The second fixing hook  412  fixed to the second fixing part  14  may be released by a second fixing hook releasing part  143  formed on the second fixing part  14 . 
     The second cleaner body  41  may include a second wire tube  413 . The second wire tube  413  may protrude from the second cleaner body  41 . The second wire tube  413  may protrude from the side of the second cleaner body  41 . The second wire tube  413  may be disposed on the first side surface  41   a  of the second cleaner body  41 . The second wire tube  413  may be disposed at one side of the second duct  411 . The second wire tube  413  may be a passage through which the wire  19  passes. The second wire tube  413  may be an opening into which the second separation preventing part  48  is inserted in one embodiment. The second wire tube  413  may communicate between the second accommodation space  415  formed in the second cleaner body  41  and the third flow passage  124   c . The second wire tube  413  may be inserted into a part of the second fixing part  14 . For example, the second wire tube  413  may be formed to have a circular or square cross section. 
     The second wire tube  413  may include a second wire through hole  413   a . The second wire through hole  413   a  may be formed by opening an interior of the second wire tube  413 . One side of the second wire through hole  413   a  may communicate with the second accommodation space  415 . The other side of the second wire through hole  413   a  may communicate with the third flow passage  124   c . A portion of the air passing through the third flow passage  124   c  may be introduced into the second accommodation space  415  by the second wire through hole  413   a . When air flows into the second accommodation space  415 , a plurality of components stored in the second accommodation space  415  may be cooled. 
     The second cleaner body  41  may include a second compartment rib  416 . The second compartment rib  416  may be provided inside the second cleaner body  41 . The second compartment rib  416  may divide the internal space of the second cleaner body  41  into a second air flow space  414  and a second accommodation space  415 . The second compartment rib  416  may protrude from an inner surface of the second cleaner body  41 . For example, the second compartment rib  416  may be formed to protrude in a direction toward an upper surface opened from the bottom of the second cleaner body  41 . The second fan module  44  and the second filter module  45  may be accommodated In the second air flow space  414 , and air may pass therethrough. The second compartment rib  416  may define a shape of the second air flow space  414  to accommodate the second fan module  44  and the second filter module  45 . The second fan module  44  and the second filter module  45  may be mounted in the second air flow space  414 . The second accommodating space  415  may include the circuit board  46  or a plurality of components including the circuit board  46 . 
     The second cleaner body  41  may include a second fan module  44  and a second filter module  45 . The second fan module  44  and the second filter module  45  may be disposed in the second air flow space  414  formed by the second compartment rib  416 . The second fan module  44  may generate a suction force for sucking outside air. The second filter module  45  may filter foreign matter from the outside air sucked in by the second fan module  44 . The second filter module  45  may be located upstream of the second fan module  44  based on the flow direction of air. The filtered air filtered by the second fan module  44  may pass through the second air flow hole  411   a  and flow into the second flow passage  124   b . The second fan module  44  may include a fan and a motor, and the second filter module  45  may include various filters. 
     The second cleaner body  41  may include the circuit board  46 . The circuit board  46  may be disposed inside the second accommodation space  415 . The circuit board  46  may control the operation of at least one of the first air cleaner  20  and the second air cleaner  40 . The circuit board  46  may include a controller, a communication unit, an information storage unit, and the like. The controller may be a microprocessor, an integrated circuit, an electrical circuit, an electrical logic circuit, and the like. The communication unit may be a transmitter and/or a receiver. The information storage unit may be a semiconductor memory. When the operation signal is inputted from at least one of the first switch  222  and the second switch  422 , the circuit board  46  may be activate at least one of the first air cleaner  20  and the second air cleaner  40 . 
     The second cleaner body  41  may include a second locking hook  417 . The second locking hook  417  may be provided in plurality. The second locking hook  417  may allow the second catching part  50  and the second cleaner body  41  to be coupled to each other. The second locking hook  417  may protrude from the side of the second cleaner body  41 . The plurality of second locking hooks  417  may be located on the second side surface  41   b  and the third side surface  41   c  of the second cleaner body  41 . A portion of the second locking hook  417  protruding outward may be bent in a direction toward the second protrusion  410 . The second locking hook  417  may protrude outward from the second side surface  41   b  and the third side surface  41   c  and then be bent in a direction toward the first side surface  41   a . The second locking hook  417  may be fixed to the second catching part  50  by the bent portion of the second locking hook  417 , and separation of the second locking hook  417  from the second catching part  50  may be prevented. 
     The second cleaner body  41  may include a second opening  419 . The second opening  419  may be an opening through which the second separation preventing strap  481  of the second separation preventing part  48  passes. The second opening  419  may be located on the first side surface  41   a . The second opening  419  may be formed in a size corresponding to the second separation prevention strap  481 . For example, an opening of any one of the plurality of second openings  419  may be located near the second protrusion  410 , and the other opening may be located near the second wire tube  413 . The second wire tube  413  and the second protrusion  410  may be located between one opening and the other opening. The second air cleaner  40  may be easily folded to the mask body  10  by the second separation preventing part  48  provided in the one opening and the other opening. In the present embodiment, the second opening  419  positioned in the second cleaner body  41  may be referred to as the other side opening. 
     The second air cleaner  40  may include a second cleaner cover  42 . The second cleaner cover  42  may cover the second cleaner body  41 . The second cleaner cover  42  may be detachably mounted on the opened upper surface of the second cleaner body  41  by the second cover fixing part  407  and the second cover coupling part. When the second cleaner cover  42  is mounted on the second cleaner body  41 , the second cleaner cover  42  may contact the second compartment rib  416 . When the second cleaner cover  42  is mounted to the second cleaner body  41 , the inner space of the second cleaner body  41  may be partitioned into the second air flow space  414  and the second accommodation space  415 . 
     The second cleaner cover  42  may include a second suction opening  421 . The second suction opening  421  may be formed with a plurality of holes or may have a mesh shape at the second cleaner cover  42 . Some of the plurality of second suction openings  421  may communicate the second air flow space  414 . Those second suction openings  421  may be located above the second air flow space  414 . The remaining of the plurality of second suction openings  421  may communicate with the second accommodation space  415 . The remaining plurality of second suction openings  421  may be located above the second accommodation space  415 . Air passing through the some of the plurality of second suction openings  421  may be sucked into the second air flow space  414 . The second accommodation space  415  may be ventilated by the air flowing in or out through the remaining part of the plurality of second suction openings  421 . Large foreign matter included in the outside air may be filtered by the second suction opening  421 . 
     The second cleaner cover  42  may include a second switch  422 . The second switch  422  may be exposed to the outer side of the second cleaner cover  42 . The second switch  422  may be an operation switch for operating the second air cleaner  40 . The second switch  422  may be provided as a power switch to turn on/off the second air cleaner  40 . The second switch  422  may be used as an operation switch for controlling the operation of the second air cleaner  40  in accordance to the duration of the second switch  422  pressed, the number of times the second switch  422  is pressed, etc. In the present embodiment, the second switch  422  shows as being one, however, a plurality of switches may be provided as needed. The plurality of switches may also be referred to as a switch. 
     The second cleaner cover  42  may include a switch circuit board for driving the second switch  422 . The switch circuit board may be located on an inner surface of the second cleaner cover  42  corresponding to the second accommodation space  415 . When the second cleaner body  41  and the second cleaner cover  42  are coupled, the switch circuit board may be stored in the second accommodation space  415 . 
       FIG. 9  is a view showing the first air cleaner fixed to the first fixing part according to the first embodiment of the present invention, and  FIG. 10  is a view showing the second air cleaner fixed to the second fixing part according to the first embodiment of the present invention. 
     The mask body  10  according to the present embodiment may include the first fixing part  13  and the second fixing part  14 . The first fixing part  13  and the second fixing part  14  may allow the first air cleaner  20  and the second air cleaner  40  to be coupled to the mask body  10 . The first air cleaner  20  may be movably coupled to the first fixing part  13 , and the second air cleaner  40  may be movably coupled to the second fixing part  14 . 
     Referring to  FIG. 9 , the first fixing part  13  may include a first fixing body  130  forming a body. The first fixing body  130  may be fixed to the mask body  10 . The first fixing body  130  may be fixed between the front cover  12  and the frame  11 . The first fixing body  130  may be inserted into and fixed to the first fixing recess  129   a  of the mask body  10 . When the first fixing part  13  is fixed to the first fixing recess  129   a , one side of the first flow passage  124   a  and on one side of the third flow passage  124   c  may be shielded. 
     The first fixing body  130  may include a first duct insertion hole  131 . The first duct insertion hole  131  may be an opening into which the first duct  211  of the first air cleaner  20  is inserted. In another embodiment, the first fixing body may include the first duct and the first air cleaner may include the first duct insertion hole. When the first duct  211  is inserted into the first duct insertion hole  131 , the first cleaner body  21  may be fixed to the first fixing body  130 . The first duct insertion hole  131  may be formed in a shape corresponding to the first duct  211 . When the first duct  211  is inserted into the first duct insertion hole  131 , the first flow passage  124   a  of the mask body  10  and the first air flow hole  211   a  of the first duct  211  may be in communication with each other. The first duct insertion hole  131  may be formed by opening a portion of the first fixing body  130 . 
     When the first fixing part  13  and the first cleaner body  21  are coupled to each other, one surface of the first fixing body  130  and the first protrusion  210  of the first cleaner body  21  may be in contact with each other. When the first protrusion  210  contacts one surface of the first fixing body  130 , the first duct  211  may be inserted into the first duct insertion hole  131  and the coupling may be sealingly made. The first protrusion  210  may be positioned between the first fixing part  13  and the first cleaner body  21  to form a space in which a part of the first catching part  30  may be disposed. 
     The first fixing body  130  may include a first wire tube insertion hole  132 . The first wire tube insertion hole  132  may be an opening into which the first wire tube  213  of the first air cleaner  20  may be inserted. The first wire tube insertion hole  132  may be formed in a shape corresponding to the first wire tube  213 . When the first wire tube  213  is inserted into the first wire tube insertion hole  132 , the third flow passage  124   c  of the mask body  10  and the first wire passage hole  213   a  of the first wire tube  213  may be in communication with each other. The first wire tube insertion hole  132  may be formed by opening a portion of the first fixing body  130 . 
     The first fixing body  130  may include a first fixing hook release part  133 . The first fixing hook release part  133  may be located at one side of the first fixing body  130 . For example, the first fixing hook release part  133  may be located at one side of the first fixing body  130  that faces the front cover  12 . The first fixing hook release part  133  may be exposed to the outside environment by passing through a portion of the front cover  12  when the front cover  12  and the frame  11  are coupled to each other (see  FIG. 1 ). An opening may be formed in the front cover  12  to expose the first fixing hook release part  133  to the outside environment. When the first fixing hook release part  133  is operated, the first air cleaner  20  fixed to the first fixing part  13  may be separated. The first fixing hook release part  133  may release the first fixing hook  212  fixed to the first fixing part  13 . For example, the first fixing hook release part  133  may be provided as a button. When the button is pressed, the first fixing hook release part  133  applies an external force to the first fixing hook  212  so as to be released from the first fixing part  13 . The first fixing hook  212  may separate from the first fixing part  13 . 
     The first fixing body  130  may include a third opening  138 . The third opening  138  may be formed by opening a portion of the first fixing body  130 . The third opening  138  may be an opening through which the first separation preventing strap  281  of the first separation preventing part  28  passes. The third opening  138  may be formed in a size such that the first separation preventing strap  281  may be located inside. The third opening  138  may prevent the first separation preventing protrusion  282  from being separated from the first fixing part  13 . The third opening  138  may be formed to have a diameter larger than the diameter of the first separation preventing strap  281  and smaller than the diameter of the first separation preventing protrusion  282 . The first separation preventing protrusion  282  may be prevented from separating at one side of the first fixing part  13  after passing through the third opening  138 . In this embodiment, the third opening  138  located in the first fixing body  130  may be referred to as one side opening. 
     The mask device  1  may include the first separation preventing part  28  coupling the first fixing part  13  and the first air cleaner  20 . The first separation preventing part  28  may be provided in plurality. 
     The first separation preventing part  28  may include a first separation preventing strap  281 , a first separation preventing protrusion  282 , and a second separation preventing protrusion  283 . The first separation preventing protrusion  282  may be referred to as one side separation preventing protrusion, and the third separation preventing protrusion  283  may be referred to as the other separation preventing protrusion. The first separation preventing strap  281  may extend in the longitudinal direction. The first separation preventing protrusion  282  may be provided at one end of the first separation preventing strap  281 , the second separation preventing protrusion  283  may be provided at the other end of the first separation preventing strap  281 . The first separation preventing protrusion  282  and the second separation preventing protrusion  283  may be configured to have a larger diameter or larger size than the first separation preventing strap  281 . 
     The first separation preventing strap  281  may pass through the first opening  219  at the first cleaner body  21  and the third opening  138  at the first fixing part  13 . The first separation prevention protrusion  282  may be located at one side of the first fixing part  13 , and the second separation prevention protrusion  283  may be located at one side of the first cleaner body  21 . The first separation preventing protrusion  282  may limit the separation from the first fixing part  13 . The second separation preventing protrusion  283  may limit the separation from the first cleaner body  21 . 
     In one embodiment, the second separation preventing protrusion  283  may be locked in the first cleaner body  21  and immovable. 
     At least one of the first separation preventing protrusion  282  and the second separation preventing protrusion  283  may be released from at least one of the first fixing part  13  and the first cleaner body  21 . 
     In another embodiment, the first separation preventing part  28  may be located in the first wire tube insertion hole  132  and the first wire passage hole  213   a . In this case, the first separation preventing protrusion  282  and the second separation preventing protrusion  283  may be formed to have a size that may be caught in the first wire tube insertion hole  132  and the first wire passage hole  213   a . The first separation preventing protrusion  282  and the second separation preventing protrusion  283  may be caught by the first wire tube insertion hole  132  and the first wire passage hole  213   a , respectively, so that the release of the first fixing part  13  from the first cleaner body  21  may be limited. 
     Referring to  FIG. 10 , the second fixing part  14  may include a second fixing body  140  forming a body. The second fixing body  140  may be fixed to the mask body  10 . The second fixing body  140  may be fixed between the front cover  12  and the frame  11 . The second fixing body  140  may be inserted into and fixed to the second fixing recess  129   b  of the mask body  10 . When the second fixing part  14  is fixed to the second fixing part mounting groove  129   b , one side of the second flow passage  124   b  and the other side of the third flow passage  124   c  may be shielded. 
     The second fixing body  140  may include a second duct insertion hole  141 . The second duct insertion hole  141  may be an opening into which the second duct  411  of the second air cleaner  40  is inserted. In another embodiment, the second fixing body may include the second duct and the second air cleaner may include the second duct insertion hole. When the second duct  411  is inserted into the second duct insertion hole  141 , the second cleaner body  41  may be fixed to the second fixing body  140 . The second duct insertion hole  141  may be formed in a shape corresponding to the second duct  411 . When the second duct  411  is inserted into the second duct insertion hole  141 , the second flow passage  124   b  of the mask body  10  and the second air flow hole  411   a  of the second duct  411  may be in communication with each other. The second duct insertion hole  141  may be formed by opening a portion of the second fixing body  140 . 
     When the second fixing part  14  and the second cleaner body  41  are coupled to each other, one surface of the second fixing body  140  and the second protrusion  410  of the second cleaner body  41  may be in contact with each other. When the second protrusion  410  contacts one surface of the second fixing body  140 , the second duct  411  may be inserted into the second duct insertion hole  141  and the coupling may be sealingly made. The second protrusion  410  may be positioned between the second fixing part  14  and the second cleaner body  41  to form a space in which a part of the second catching part  50  may be disposed. 
     The second fixing body  140  may include a second wire tube insertion hole  142 . The second wire insertion hole  142  may be an opening into which the second wire tube  413  of the second air cleaner  40  may be inserted. The second wire tube insertion hole  142  may be formed in a shape corresponding to the second wire tube  413 . When the second wire tube  413  is inserted into the second wire tube insertion hole  142 , the third flow passage  124   c  of the mask body  10  and the second wire passage hole  413   a  of the second wire tube  413  may be in communication with each other. The second wire tube insertion hole  142  may be formed by opening a portion of the second fixing body  140 . 
     The second fixing body  140  may include a second fixing hook release part  143 . The second fixing hook release part  143  may be located at one side of the second fixing body  140 . For example, the second fixing hook release part  143  may be located at one side of the first fixing body  130  facing the front cover  12 . The second fixing hook release part  143  may be exposed to the outside environment by passing through a portion of the front cover  12  when the front cover  12  and the frame  11  are coupled to each other (see  FIG. 2 ). An opening may be formed in the front cover  12  to expose the second fixing hook release part  143  to the outside environment. When the second fixing hook release part  143  is operated, the second air cleaner  40  fixed to the second fixing part  14  may be separated. The second fixing hook release part  143  may release the second fixing hook  412  fixed to the second fixing part  14 . For example, the second fixing hook release part  143  may be provided as a button. When the button is pressed, the second fixing hook release part  143  applies an external force to the second fixing hook  412  so as to be released from the second fixing part  14 . The second fixing hook  412  may separate from the second fixing part  14 . 
     The second fixing body  140  may include a fourth opening  148 . The fourth opening  148  may be formed by opening a portion of the second fixing body  140 . The fourth opening  148  may be an opening through which the second separation preventing strap  481  of the second separation preventing part  48  passes. The fourth opening  148  may be formed in a size such that the second separation preventing strap  481  may be located inside. The fourth opening  148  may prevent the third separation preventing protrusion  482  from being separated from the second fixing part  14 . The fourth opening  148  may be formed to have a diameter larger than the diameter of the second separation preventing strap  481  and smaller than the diameter of the third separation preventing protrusion  482 . The third separation preventing protrusion  482  may be prevented from separating at one side of the second fixing part  14  after passing through the fourth opening  148 . In this embodiment, the fourth opening  148  located in the second fixing body  140  may be referred to as one side opening. 
     The mask device  1  may include a second separation preventing part  48  coupling the second fixing part  14  and the second air cleaner  40 . The second separation preventing part  48  may be provided in plurality. 
     The second separation prevention part  48  may include a second separation prevention strap  481 , a third separation prevention protrusion  482 , and a fourth separation prevention protrusion  483 . The second separation prevention strap  481  may extend in the longitudinal direction. The third separation prevention protrusion  482  may be provided at one end of the second separation prevention strap  481 , and the fourth separation prevention protrusion  483  may be provided at the other end of the second separation prevention strap  481 . The third separation preventing protrusion  482  and the fourth separation preventing protrusion  483  may have a larger diameter or larger size than the second separation preventing strap  481 . 
     The second separation preventing strap  481  may pass through the second opening  419  at the second cleaner body  41  and the fourth opening  148  at the second fixing part  14 . The third separation prevention protrusion  482  may be located at one side of the second fixing part  14 , and the fourth separation prevention protrusion  483  may be located at one side of the second cleaner body  41 . The third separation preventing protrusion  482  may limit the separation from the second fixing part  14 . The fourth separation preventing protrusion  483  may limit the separation from the second cleaner body  41 . 
     In one embodiment, the fourth separation preventing protrusion  483  may be locked in the second cleaner body  41  and immovable. 
     At least one of the third separation preventing protrusion  482  and the fourth separation preventing protrusion  483  may be released from at least one of the second fixing part  14  and the second cleaner body  41 . 
     In another embodiment, the second separation preventing part  48  may be located in the second wire tube insertion hole  142  and the second wire passage hole  413   a . In this case, the third separation preventing protrusion  482  and the fourth separation preventing protrusion  483  may be formed to have a size that may be caught by the second wire tube insertion hole  142  and the second wire passing hole  413   a . The third separation preventing protrusion  482  and the fourth separation preventing protrusion  483  may be caught by the second wire tube insertion hole  142  and the second wire passage hole  413   a , respectively, so that the release of the second fixing part  14  and the second cleaner body  41  may be limited. 
       FIG. 11  is a view showing a folding state of the mask device according to the first embodiment of the present invention. 
     Referring to  FIG. 11 , when the fixing hook release parts  133  and  143  are operated, the first air cleaner  20  and the second air cleaner  40  may move with respect to the mask body  10 . The first catching part  30  coupled to the first air cleaner  20  and the second catching part  50  coupled to the second air cleaner  40  may also move relative to the mask body  10 . In the present embodiment, “move” refers to the first air cleaner  20 , the first catching part  30 , the second air cleaner  40  and the second catching part  50  moved to be folded or rotated to fold. 
     The first duct  211  of the first air cleaner  20  may be inserted into and fixed to one end portion of the mask body  10 . A second duct  411  of the second air cleaner  40  may be inserted into and fixed to the other end portion of the mask body  10 . One side of the mask body  10  may be defined as the left side, and the other side of the mask body  10  may be defined as the right side. The first catching part  30  may be coupled to the first air cleaner  20 , and a portion of the first catching part  30  may be disposed between one end portion of the first air cleaner  20  and the mask body  10 . The second catching part  50  may be coupled to the second air cleaner  40 , and a portion of the second catching portion  50  may be disposed between one end portion of the second air cleaner  40  and the mask body  10 . 
     The first catching part  30  may be spaced apart from the mask body  10  together with the first air cleaner  20  when the first air cleaner  20  is spaced apart from the mask body  10 . The second catching part  50  may be spaced apart from the mask body  10  together with the second air cleaner  40  when the second air cleaner  40  is spaced apart from the mask body  10 . The first air cleaner  20  and the first catching part  30  may be moved in a direction toward the frame  11  of the mask body  10  while being spaced apart from the mask body  10 . The first air cleaner  20  and the first catching part  30  may rotate counterclockwise with reference to  FIG. 11 . The second air cleaner  40  and the second catching part  50  may be moved in a direction toward the frame  11  of the mask body  10  while being spaced apart from the mask body  10 . The second air cleaner  40  and the second catching part  50  may rotate clockwise with reference to  FIG. 11 . 
     The first air cleaner  20  may be fixed to the mask body  10  by the first fixing hook  212  of the first duct  211 . The second air cleaner  40  may be fixed to the mask body  10  by the second fixing hook  412  of the second duct  411 . The first fixing hook  212  may be released by the first fixing hook release part  133  of the mask body  10 . The second fixing hook  412  may be released by the second fixing hook release part  143  of the mask body  10 . For example, the first fixing hook release part  133  and the second fixing hook release part  143  may be configured as push buttons. When the user presses P the first fixing hook release part  133  and the second fixing hook release part  143 , the first fixing hook  212  and the second fixing hook  412  may be released from the mask body  10 . When the first fixing hook  212  and the second fixing hook  412  are separated from the mask body  10 , the first duct  211  and the second duct  411  may be separated from the mask body  10 . The first and second fixing hooks  212  and  412  and the first and second fixed hook release parts  133  and  143  will be further described with reference to  FIGS. 12 and 13 . 
     The first air cleaner  20 , the first catching part  30 , the second air cleaner  40 , and the second catching part  50  may shield an external space of the frame  11  from foreign matter. 
       FIG. 12  is a cross-sectional view showing a state in which a mask body and an air cleaner are coupled according to the first embodiment of the present invention, and  FIG. 13  is a cross-sectional view showing a state in which a mask body and an air cleaner are separated according to the first embodiment of the present invention. 
     Referring to  FIG. 12 , a first air cleaner  20  may be mounted on one side of the mask body  10 , and a second air cleaner  40  may be mounted on the other side of the mask body  10 . The air cleaners  20  and  40  of any one of the first air cleaner  20  and the second air cleaner  40 . The ducts  211  and  411  of the air cleaners  20  and  40  may be inserted into the duct insertion holes  131  and  141  of the mask body  10 . The duct insertion holes  131  and  141  may be formed in the fixing parts  13  and  14  of the mask body  10 . The ducts  211  and  411  and the duct insertion holes  131  and  141  may be formed in sizes corresponding to each other. Air flow holes  211   a  and  411   a  may be formed inside the ducts  211  and  411 , and the air flow holes  211   a  and  411   a  may communicate with air flow spaces  214  and  414  of the air cleaners  20  and  40 . 
     The air filtered in the air flow spaces  214  and  414  of the air cleaners  20  and  40  may pass through the air flow holes  211   a  and  411   a  and then flow into the mask body  10 . The mask body  10  may include flow paths  124   a  and  124   b  communicating with the duct insertion holes  131  and  141 . The filtered air passing through the air flow holes  211   a  and  411   a  may flow into the flow paths  124   a  and  124   b . The filtered air may flow through the air flow holes  211   a  and  411   a  and the flow passages  124   a  and  124   b  and flow to the inlets  111   a  and  111   b  of the frame  11  to be supplied to the user. 
     The ducts  211  and  411  may include fixing hooks  212  and  412 , and the duct insertion holes  131  and  141  may include hook coupling grooves  135  and  145 . The hook coupling grooves  135  and  145  may include a first hook coupling groove  135  disposed at the first fixing part  13  and a second hook coupling groove  145  disposed at the second fixing part  14 . The fixing hook release parts  133  and  143  may be disposed in the hook coupling grooves  135  and  145  into which the fixing hooks  212  and  412  are inserted. When the ducts  211  and  411  are inserted into the duct insertion holes  131  and  141 , the fixing hooks  212  and  412  may elastically deform and get caught in the hook coupling grooves  135  and  145 . The fixing hook release parts  133  and  143  may allow the fixing hooks  212  and  412  that are fixed to the hook coupling grooves  135  and  145  to be released from the hook coupling grooves  135  and  145 . 
     The fixing hook release parts  133  and  143  may be exposed to the outside through a portion of the fixing body  130  and  140 . The fixed hook release parts  133  and  143  exposed to the outside may be manipulated by a user so that the fixing hooks  212  and  412  may be separated from the hook coupling grooves  135  and  145 . In order to expose the fixing hook release parts  133  and  143  to the outside, a portion of the front cover  12  may include openings  120   a  and  120   b . The openings  120   a  and  120   b  may be located at both sides of the front cover  12 . 
     A portion of the catching parts  30  and  50  may be positioned between the mask body  10  and the air cleaners  20  and  40 . The portion of the catching parts  30  and  50  may prevent the air filtered between the mask body  10  and the air cleaners  20  and  40  from leaking into the outer environment. Portion of the catching parts  30  and  50  may include duct through holes  311  and  511  through which the ducts  211  and  411  pass, and through holes  318  and  518  through which the separation preventing parts  28  and  48  pass. The portion of the catching parts  30  and  50  may include the duct through holes  311  and  511  and the through holes  318  and  518 , and may be positioned between the fixing parts  13  and  14  and the air cleaners  20  and  40 . 
     In the present embodiment, the ducts  211  and  411  are disposed in the air cleaners  20  and  40 , and the duct insertion holes  131  and  141  are disposed in the fixing parts  13  and  14 . 
     Referring to  FIG. 13 , the fixing hook release parts  133  and  143  may be manipulated to separate the ducts  211  and  411  from the duct insertion holes  131  and  141 . When the fixing hooks  212  and  412  are separated from the hook coupling grooves  135  and  145  by the fixing hook release parts  133  and  143 , the ducts  211  and  411  may be separated from the duct insertion holes  131  and  141 . When the ducts  211  and  411  are separated from the duct insertion holes  131  and  141 , the air cleaners  20  and  40  may move away from the fixing parts  13  and  14 . The catching parts  30  and  50  to which the air cleaners  20  and  40  are coupled may move away from the fixing parts  13  and  14  together with the air cleaners  20  and  40 . The fixing hooks  212  and  412  may elastically deform when passing through the duct insertion holes  131  and  141 . When the fixing hooks  212  and  412  are separated from the duct insertion holes  131  and  141 , the mask body  10  may be spaced apart from the air cleaners  20  and  40 , and the catching parts  30  and  50 . 
     The mask body  10  and the air cleaners  20  and  40  may be coupled by the separation preventing parts  28  and  48 . When the air cleaners  20  and  40  are separated from the mask body  10 , the separation preventing parts  28  and  48  limit separation of the air cleaners  20  and  40  from the mask body  10  by a predetermined distance or less. One side of the separation preventing part  28 ,  48  may be fixed to the fixing part  13 ,  14  of the mask body  10 , and the other side of the separation preventing part  28 ,  48  may be the air cleaner  20 ,  40 . 
     The air cleaners  20  and  40  may rotate in a state spaced apart from the mask body  10  by a predetermined distance from the separation preventing parts  28  and  48 . The catching parts  30  and  50  to which the air cleaners  20  and  40  are coupled may rotate with respect to the mask body  10  together with the air cleaners  20  and  40 . When the air cleaners  20  and  40  and the catching parts  30  and  50  are rotated with respect to the mask body  10 , the mask device  1  may be considered folded. When the air cleaners  20  and  40  are folded with respect to the mask body  10 , the size of the mask device  1  may be reduced. The air cleaners  20  and  40  may cover one surface of the mask body  10  to prevent foreign substances from being introduced into the one surface of the mask body  10 . 
       FIG. 14  is a view showing a folded state of the mask device according to the first embodiment of the present invention. 
     Referring to  FIG. 14 , in the mask device  1  according to the embodiment, the first air cleaner  20  and the second air cleaner  40  may be folded with respect to the mask body  10 . When the mask device  1  is being used, the first air cleaner  20  and the second air cleaner  40  may be fixed to both end portions of the mask body  10 . The user&#39;s face may be located between the first air cleaner  20  and the second air cleaner  40  fixed to both end portions of the mask body  10 . 
     The first fixing part  13  of the mask body  10  may include the first duct insertion hole  131  and the first wire tube insertion hole  132 . When the first air cleaner  20  is fixed to the first fixing part  13 , the first duct  211  of the first air cleaner  20  may be inserted into the first duct insertion hole  131 . The first wire tube  213  may be inserted into the first wire tube insertion hole  132 . When the first duct  211  and the first wire tube  213  are inserted, the first protrusion  210  of the first air cleaner  20  may contact the first fixing part  13  to limit the amount the first duct  211  may be inserted into the first duct insertion hole  131 . When the first duct  211  is inserted into the first duct insertion hole  131 , the first fixing hook  212  of the first air cleaner  20  may lock to the first fixing part  13 . A portion of the first catching part  30  is disposed between the first air cleaner  20  and the first fixing part  13 , and the mask device may be mounted on the user&#39;s face by the first catching part  30 . 
     The second fixing part  14  of the mask body  10  may include the second duct insertion hole  141  and the second wire tube insertion hole  142 . When the second air cleaner  40  is fixed to the second fixing part  14 , the second duct  411  of the second air cleaner  40  may be inserted into the second duct insertion hole  141 . The second wire tube  413  may be inserted into the second wire tube insertion hole  142 . When the second duct  411  and the second wire tube  413  are inserted, the second protrusion  410  of the second air cleaner  40  may contact the second fixing part  14  to limit the amount of the second duct  411  may be inserted into the second duct insertion hole  141 . When the second duct  411  is inserted into the second duct insertion hole  141 , the second fixing hook  412  of the second air cleaner  40  may lock to the second fixing part  14 . A portion of the second catching part  50  is disposed between the second air cleaner  40  and the second fixing part  14 , and a mask device may be mounted on the user&#39;s face by the second catching part  50 . 
     When the mask device  1  is not used, the first air cleaner  20  and the second air cleaner  40  may be folded with respect to the mask body  10 . When the first air cleaner  20  and the second air cleaner  40  are folded, the first air cleaner  20  and the second air cleaner  40  may cover the frame  11  of the mask body  10 . The first air cleaner  20  may be folded by rotating at the left end of the mask body  10  in a direction toward the frame  11 . The second air cleaner  40  may be folded by rotating at the right end of the mask body  10  in the direction toward the frame  11 . In the present embodiment, the first air cleaner  20  and the second air cleaner  40  may be rotatably coupled to the mask body  10  by the first separation preventing part  28  and the second separation preventing part  48  to close a part of the breathing space of the mask body  10  covering the user&#39;s nose and mouth. Thus, by closing the part of the breathing space of the mask body  10  from the outside environment, exposure to contamination may be minimized. 
     When the first fixing hook release part  133  of the first fixing part  13  is operated, the first fixing hook  212  that is locked to the first fixing part  13  may be released. When the first fixing hook  212  is released, the first duct  211  may be separated from the first fixing part  13 . The first cleaner body  21  separated from the first fixing part  13  may be rotated in a direction toward the frame  11 . Since the first fixing part  13  and the first cleaner body  21  are coupled to each other by the first separation preventing part  28 , the first fixing part  13  and the first cleaner body  21  may be limited in being spaced apart by a predetermined distance or less. 
     When the second fixing hook release part  143  of the second fixing part  14  is operated, the second fixing hook  412  that is locked to the second fixing part  14  may be released. When the second fixing hook  412  is released, the second duct  411  may be separated from the second fixing part  14 . The second cleaner body  41  separated from the second fixing part  14  may be rotated in a direction toward the frame  11 . Since the second fixing part  14  and the second cleaner body  41  are coupled to each other by the second separation preventing part  48 , the second fixing part  14  and the second cleaner body  41  may be limited in being spaced apart by a predetermined distance or less. 
     In the present embodiment, the first air cleaner  20  and the second air cleaner  40  are connected to the mask body  10  by the first separation preventing part  28  and the second separation preventing part  48 , and described as being rotated toward and folded. However, in another embodiment, a hinge may be provided between the first air cleaner  20  and the first fixing part  13 , and a hinge may be provided between the second air cleaner  40  and the second fixing part  14 . The first air cleaner  20  and the second air cleaner  40  may be rotated and folded with respect to the mask body  10  by the hinges. 
       FIG. 15  is a view showing the first catching part according to the first embodiment of the present invention, and  FIG. 16  is a view showing the second catching part according to the first embodiment of the present invention. 
     Referring to  FIGS. 15 and 16 , the mask device  1  according to the embodiment may include the first catching part  30  and the second catching part  50 . The first catching part  30  may be detachably mounted to the first air cleaner  20 , and the second catching part  50  may be detachably mounted to the second air cleaner  40 . The first catching part  30  and the second catching part  50  may allow the first air cleaner  20  and the second air cleaner  40  to be supported by the user&#39;s ears. For example, the first catching part  30  and the second catching part  50  may be formed in a ring shape that is fixed to the user&#39;s ears. The first catching part  30  and the second catching part  50  may be formed in a leg shape to be fixed to a part of the user&#39;s ears. The leg may be formed in a structure such as a pair of glasses that are fastened to a part of the user&#39;s ears. 
     Hereinafter, the first catching part  30  and the second catching part  50  will be described in order. 
     Referring to  FIG. 15 , the first catching part  30  may include the first hanger body  31  forming the body. In the present embodiment, the first hanger body  31  may be formed in a ring shape having a closed curve. The first cleaner body  21  may be mounted on one side of the first hanger body  31 , and may be fixed to the user&#39;s ear on the other side of the first hanger body  31 . The first cleaner body  21  may be located inside one side of the first hanger body  31 , and the user&#39;s ear may be located inside the other side of the first hanger body  31 . A part of the first hanger body  31  may be in contact with the first cleaner body  21 . A portion of the first hanger body  31  may be in contact with the first side surface  21   a , the second side surface  21   b , and the third side surface  21   c  of the first cleaner body  21 . 
     The first hanger body  31  may include a first body  31   a , a second body  31   b , a third body  31   c , and a fourth body  31   d . The first hanger body  31  may be formed by connecting the first to the fourth body. The first body  31   a  may be a part disposed between the first air cleaner  20  and the first fixing part  13 . The fourth body  31   d  may be a part which is fixed to the user&#39;s ear. The second body  31   b  and the third body  31   c  may be parts connecting the first body  31   a  and the fourth body  31   d.    
     The first hanger body  31  may include a first duct through hole  311 . The first duct through hole  311  may be disposed in the first body  31   a  of the first hanger body  31 . The first duct  211  of the first cleaner body  21  may pass through the first duct through hole  311 . The first duct through hole  311  may be an opening into which the first protrusion  210  of the first cleaner body  21  is inserted and fixed. The first duct through hole  311  may be formed to correspond to the first protrusion  210 . The first duct  211  may be inserted into the first duct insertion hole  131  with the first protrusion  210  being inserted into the first duct through hole  311 . 
     The first body  31   a  of the first hanger body  31  may have one surface in contact with the first cleaner body  21  and the other surface in contact with the first fixing body  130 . The first body  31   a  of the first hanger body  31  may be interposed between the first cleaner body  21  and the first fixing body  130  to perform a packing function. The first hanger body  31  may be interposed between the first cleaner body  21  and the first fixing body  130  to support the left end of the mask body  10 . The first protrusion  210  may be inserted into and fixed to the first duct through hole  311 . In the present embodiment, the first duct through hole  311  may be referred to as the first protrusion part insertion hole to which the first protrusion  210  is inserted and fixed. 
     The first hanger body  31  may include a first wire tube through hole  312 . The first wire tube through hole  312  may be disposed in the first body  31   a  of the first hanger body  31 . The first wire tube through hole  312  may be an opening through which the first wire tube  213  of the first cleaner body  21  passes. The first wire tube through hole  312  may be formed to correspond to the first wire tube  213 . The first wire tube  213  may be inserted into the first wire tube insertion hole  131  while the first wire tube  213  is being inserted into the first wire tube through hole  312 . The first hanger body  31  may be interposed between the first cleaner body  21  and the first fixing body  130  to support a left end of the mask body  10 . 
     The first hanger body  31  may include a first through hole  318 . The first through hole  318  may be an opening through which the first separation preventing strap  281  of the first separation preventing part  28  passes. The first through hole  318  may be formed to correspond to the first separation prevention strap  281 . The first through hole  318  may be disposed in the first body  31   a  of the first hanger body  31 . The first through hole  318  may be disposed at one side of the first duct through hole  311 , and the first wire tube insertion hole  132  may be disposed at the other side of the first duct through hole  311 . 
     The first hanger body  31  may include a first handle  314 . The first handle  314  may be located on the fourth body  31   d  of the first hanger body  31 . The first handle  314  may be formed by protruding a portion of the first hanger body  31  outward. The fourth body  31   d  of the first hanger body  31  may include one surface facing the user&#39;s ear and the other surface facing the outside. The first handle  314  may protrude outward from the other surface of the fourth body  31   d . The first handle  314  may be a part that the user grabs when the first hanger body  31  is mounted on the user&#39;s ear. 
     The first hanger body  31  may include a first hook groove  317 . The first hook groove  317  may be provided in plurality. The first locking hook  217  of the first cleaner body  21  may be locked into the first hook groove  317 . The first hook groove  317  may be disposed at a position corresponding to the first locking hook  217 . The first hook groove  317  may be disposed at the second body  31   b  and the third body  31   c  of the first hanger body  31 . The first hook groove  317  may be formed by recessing a portion of the first hanger body  31  so that the first locking hook  217  may be inserted therein. In detail, the second body  31   b  and the third body  31   c  may be defined as an inner surface and an outer surface. The first hook groove  317  may be formed by recessing the inner surfaces of the second body  31   b  and the third body  31   c  toward the outer surface. The first hook groove  317  may be recessed in a shape corresponding to a bent portion so that the bent portion of the first locking hook  217  may be inserted and locked. That is, the first hook groove  317  may be opened to a shape corresponding to the first locking hook  217  so that the first locking hook  217  may be fitted and locked. 
     The first catching part  30  may include a first contact part  32 . The first contact part  32  may be provided on an inner surface of the first hanger body  31 . The inner surface of the first hanger body  31  may be a surface in contact with the user&#39;s ear. The first contact part  32  may be disposed on the fourth body  31   d  of the first catching part  30 . The first contact part  32  may further extend from the fourth body  31   d  of the first catching part  30  toward at least one of the second body  31   b  and the third body  31   c . The first contact part  32  may be disposed between the user&#39;s ear and the first catching part  30  to distribute a pressure applied to the user&#39;s ear. The first contact part  32  may be made with a material having a predetermined elastic force to distribute the pressure applied to the user&#39;s ear. 
     In one embodiment, the first contact part  32  may further include a sensor for obtaining biometric information from a user&#39;s ear. The sensor may be provided inside the first contact part  32  and may contact the user&#39;s ear to obtain biometric information. For example, the operation of the mask device  1  may be controlled by the controller based on the biometric information obtained through the sensor. 
     The first hanger body  31  may include a first recessed part  319 . The first recessed part  319  may be formed by recessing a portion of the first hanger body  31 . Y in  FIG. 15  is a cross-sectional view showing a part of the first hanger body  31 . Referring to Y of  FIG. 15 , the first recessed part  319  may be formed by recessing an outer surface of the first hanger body  31  toward an inner surface. The first recessed part  319  may be disposed at the second body  31   b  and the fourth body  31   d  of the first hanger body  31 . The first recessed part  319  may be a space in which the glasses legs of the glasses may be seated when the glasses are worn after the first catching part  30  is attached to the user&#39;s ear. 
     Referring to  FIG. 16 , the second catching part  50  may include a second hanger body  51  forming a body. In the present embodiment, the second hanger body  51  may be formed in a ring shape having a closed curve. The second cleaner body  41  may be mounted on one side of the second hanger body  51 , and may be fixed to the user&#39;s ear on the other side of the second hanger body  51 . The second cleaner body  41  may be located inside one side of the second hanger body  51 , and the user&#39;s ear may be located inside the other side of the second hanger body  51 . A part of the second hanger body  51  may be in contact with the second cleaner body  41 . A part of the second hanger body  51  may be in contact with the first side surface  41   a , the second side surface  41   b , and the third side surface  41   c  of the second cleaner body  41 . 
     The second hanger body  51  may include a first body  51   a , a second body  51   b , a third body  51   c , and a fourth body  51   d . The second hanger body  51  may be formed by connecting the first to the fourth body. The first body  51   a  may be a part disposed between the second air cleaner  40  and the second fixing part  14 . The fourth body  51   d  may be a part which is fixed to the user&#39;s ear. The second body  51   b  and the third body  51   c  may be parts connecting the first body  51   a  and the fourth body  51   d.    
     The second hanger body  51  may include a second duct through hole  511 . The second duct through hole  511  may be disposed in the first body  51   a  of the second hanger body  51 . The second duct  411  of the second cleaner body  41  may pass through the second duct through hole  511 . The second duct through hole  511  may be an opening into which the second protrusion  410  of the second cleaner body  41  is inserted and fixed. The second duct through hole  511  may be formed to correspond to the second protrusion  410 . The second duct  411  may be inserted into the second duct insertion hole  141  while the second protrusion  410  is being inserted into the second duct through hole  511 . 
     The first body  51   a  of the second hanger body  51  may have one surface in contact with the second cleaner body  41  and the other surface in contact with the second fixing body  140 . The first body  51   a  of the second hanger body  51  may be interposed between the second cleaner body  41  and the second fixing body  140  to perform a packing function. The second hanger body  51  may be interposed between the second cleaner body  41  and the second fixing body  140  to support the right end of the mask body  10 . The second protrusion  410  may be inserted into and fixed to the second duct through hole  511 . In the present embodiment, the second duct through hole  511  may be referred to as a second protrusion insertion hole to which the second protrusion  410  is inserted and fixed. 
     The second hanger body  51  may include a second wire tube through hole  512 . The second wire tube through hole  512  may be disposed in the first body  51   a  of the second hanger body  51 . The second wire tube through hole  512  may be an opening through which the second wire tube  413  of the second cleaner body  41  passes. The second wire through hole  512  may be formed to correspond to the second wire tube  413 . The second wire tube  413  may be inserted into the second wire tube insertion hole  141  while the second wire tube  413  is being inserted into the second wire tube through hole  512 . The second hanger body  51  may be interposed between the second cleaner body  41  and the second fixing body  140  to support the right end of the mask body  10 . 
     The second hanger body  51  may include a second through hole  518 . The second through hole  518  may be an opening through which the second separation preventing strap  481  of the second separation preventing part  48  passes. The second through hole  518  may be formed to correspond to the second separation prevention strap  481 . The second through hole  518  may be disposed in the second body  51   a  of the second hanger body  51 . The second through hole  518  may be disposed on one side of the second duct through hole  511 , and the second wire tube insertion hole  142  may be disposed on the other side of the second duct through hole  511 . 
     The second hanger body  51  may include a second handle  514 . The second handle  514  may be located on the fourth body  51   d  of the second hanger body  51 . The second handle  514  may be formed by protruding a portion of the second hook body  51  outward. The fourth body  51   d  of the second hanger body  51  may include one surface facing the user&#39;s ear and the other surface facing the outside. The second handle  514  may protrude outward from the other surface of the fourth body  51   d . The second handle  514  may be a part that the user grabs when the second hanger body  51  is mounted on the user&#39;s ear. 
     The second hanger body  51  may include a second hook groove  517 . The second hook groove  517  may be provided in plurality. The second locking hook  417  of the second cleaner body  41  may be locked to the second hook groove  517 . The second hook groove  517  may be disposed at a position corresponding to the second locking hook  417 . The second hook groove  517  may be disposed at the second body  51   b  and the third body  51   c  of the second hanger body  51 . The second hook groove  517  may be formed by recessing a portion of the second hanger body  51  so that the second locking hook  417  may be inserted therein. In detail, the second body  51   b  and the third body  51   c  may be defined as an inner surface and an outer surface. The second hook groove  517  may be formed by recessing the inner surfaces of the second body  51   b  and the third body  51   c  toward the outer surface. The second hook groove  517  may be recessed in a shape corresponding to a bent portion so that the bent portion of the second locking hook  417  may be inserted and locked. That is, the second hook groove  517  may be opened to a shape corresponding to the second locking hook  417  so that the second locking hook  417  may be fitted and locked. 
     The second catching part  50  may include a second contact part  52 . The second contact part  52  may be provided on an inner surface of the second hanger body  51 . The inner surface of the second hanger body  51  may be a surface in contact with the user&#39;s ear. The second contact part  52  may be disposed on the fourth body  51   d  of the second catching part  50 . The second contact part  52  may further extend from the fourth body  51   d  of the second catching part  50  toward at least one of the second body  51   b  and the third body  51   c . The second contact part  52  may be disposed between the user&#39;s ear and the second catching part  50  to distribute a pressure applied to the user&#39;s ear. The second contact part  52  may be made with a material having a predetermined elastic force to distribute the pressure applied to the user&#39;s ear. 
     In one embodiment, the second contact part  52  may further include a sensor for obtaining biometric information from the user&#39;s ear. The sensor may be provided inside the second contact part  52  and may contact the user&#39;s ear to obtain biometric information. For example, the operation of the mask device  1  may be controlled based on the biometric information obtained through the sensor. 
     The second hanger body  51  may include a second recessed portion  519 . The second recessed part  519  may be formed by recessing a portion of the second hanger body  51 . Z in  FIG. 16  is a cross-sectional view showing a part of the second hanger body  51 . Referring to Z of  FIG. 16 , the second recess  519  may be formed by recessing an outer surface of the second hanger body  51  toward an inner surface. The second recessed part  519  may be disposed at the second body  51   b  and the fourth body  51   d  of the second hanger body  51 . The second recessed part  519  may be a space in which the glasses legs of the glasses may be seated when the glasses are worn after the second catching part  50  is mounted on the user&#39;s ear. 
       FIGS. 17 and 18  are views showing an air flow flowing in the mask device according to the first embodiment of the present invention. 
     Referring to  FIGS. 17 and 18 , the mask device  1  according to the embodiment may be in close contact with the user&#39;s face while covering the user&#39;s nose and mouth. The mask device  1  may be supported by the user&#39;s ears by the first catching part  30  and the second catching part  50  while the packing is in contact with the user&#39;s face. The user may operate the mask device  1  by turning on/off at least one of the first switch  222  and the second switch  422  while the mask device  1  is in close contact with the user&#39;s face. Although the mask device  1  is described as being mounted on the user&#39;s nose and mouth, the mask device  1  may also be mounted on a pet. In this case, the mask device  1  may be configured to be mounted on the head of the pet. 
     When the mask device  1  is operated, the first fan module  24  and the second fan module  44  may be operated to suck in outside air. The first fan module  24  and the second fan module  44  may be operated to suck in outside air into the first suction opening  221  and the second suction opening  421 . A flow direction of the outside air introduced through the first suction opening  221  and the second suction opening  421  is indicated by A in  FIG. 17 . The first air cleaner  20  may suck in outside air at the left side of the user&#39;s face, and the second air cleaner  40  may suck in outside air at the right side of the user&#39;s face. 
     The outside air sucked into the first suction opening  221  may be filtered by the first filter module  25 , and the outside air sucked into the second suction opening  421  may be filtered by the second filter module  45 . The filtered air may be discharged to the inlet  111   a  and  111   b  of the mask body  10  after passing through the first flow passage  124   a  and the second flow passage  124   b . The air flowing through the first flow passage  124   a  and the second flow passage  124   b  and discharged to the inlet  111   a  and  111   b  is represented by B in  FIG. 18 . The air filtered by the first air cleaner  30  may be supplied through the first inlet  111   a , and the air filtered by the second air cleaner  40  may be supplied through the second inlet  111   b . The air discharged to the inlet  111   a  and  111   b  is supplied to the user&#39;s nose and mouth, and the user may inhale in the filtered air. Since the filtered air is forced to flow by the first fan module  24  and the second fan module  44 , filtered air may be abundantly supplied to the breathing space of the mask body  10 . 
     Air exhaled from the user&#39;s nose and mouth may flow into the outlet  112   a  and  112   b  of the mask body  10 . Because the filtered air is continuously being supplied through the inlet  111   a  and  111   b  in the upper space of the breathing space of the mask body  10 , the exhaled air may flow in the lower space in the direction toward the outlet  112   a  and  112   b . Since the outlet  112   a  and  112   b  is located in front of the user&#39;s mouth, the exhaled air may be discharged through the outlet  112   a  and  112   b  quickly. The air discharged through the outlet  112   a  and  112   b  may flow into the third passage  124   c  of the mask body  10 . The flow direction of air exhaled from the user&#39;s nose and mouth is indicated by C in  FIG. 18 . The third passage  124   c  may be separated from the first passage  124   a  and the second passage  124   b  to prevent mixing of the filtered air and the discharged air. 
     The discharge port  128   a  and  128   b  may discharge the discharged air from the user&#39;s nose and mouth from the third flow passage  124   c  to the outside environment. The discharged air from the third flow passage  124   c  passes through the discharge port  128   a  and  128   b  and is discharged to the outside, and the flow direction of the air is represented by D in  FIG. 18 . In the present embodiment, since the discharge port  128   a  and  128   b  is located at the lower portion of the mask body  1 , the air discharged to the outside may be prevented from entering back into the first air cleaner  20  and the second air cleaner  40 . 
     At least one of the discharge port  128   a  and  128   b  and the outlet  112   a  and  112   b  may be provided with a check valve  118 . In this embodiment, the check valve  118  may be provided to the outlet  112   a  and  112   b . The check valve  118  may prevent backflow of discharged air back into at least one of the outlet  128   a  and  128   b  and the outlet  112   a  and  112   b . The check valve  118  may be closed when the user inhales the filtered air and may be open when the user exhales the air to be discharged. 
       FIG. 19  is a view showing a locking portion of a mask device according to a second embodiment of the present invention. 
     Some parts of the mask device according to the second embodiment of the present invention may be the same or similar as the mask device  1  according to the first embodiment. Therefore, parts being the same or similar as in the mask device  1  may be omitted from the description of the mask device  2  according to the second embodiment. Hereinafter, a specific part of the mask device  2  according to the second embodiment modified from the mask device  1  according to the first embodiment will be described. 
     The mask device  2  according to the embodiment may include a third catching part and a fourth catching part. The third catching part may be coupled to the first air cleaner  20 , and the fourth catching part may be coupled to the second air cleaner  40 . The third catching part and the fourth catching part may be in different positions of the mask device  2 , that is left and right side of the mask device  2 , but the configuration may be the same. Therefore, the third catching part and the fourth catching part will be described as the catching part  60 . 
     Referring to  FIG. 19 , the catching part  60  may include a hanger body  61  forming a body. An air cleaner may be coupled to one side of the hanger body  61 , and the user&#39;s ear may be fixed to the other side of the hanger body  61 . 
     The hanger body  61  may include an upper hanger  611  and a lower hanger  612 . One side of the upper hanger  611  and the lower hanger  612  may be connected to the air cleaner. The other side of the upper hanger  611  and the lower hanger  612  may be detachably coupled to each other. The upper hanger  611  may be a part located above the user&#39;s ear, and the lower hanger  612  may be a part located below the user&#39;s ear. 
     The hanger body  61  may include a contact part  62 . The contact part  62  may be provided on at least one of the upper hanger  611  and the lower hanger  612 . The contact part  62  may intervene between at least one of the upper hanger  611  and the lower hanger  612  and the user&#39;s ear to distribute the pressure applied to the user&#39;s ear. The contact part  62  may be made of a material that may be easily deformed and has elasticity to disperse the pressure applied to the user&#39;s ear. 
     The hanger body  61  may include a length adjusting part  70 . The length adjusting part  70  may adjust the length of the hanger body  61  fixed to the user&#39;s ear. The length adjusting part  70  may be used to adjust the length of the hanger body  61  so that the mask body  10  may be in close contact with the user&#39;s face. The length adjusting part  70  may be adjusted to correspond to various users having faces of different sizes. In the present embodiment, the length adjusting part  70  may adjust the length of the hanger body  61  by adjustably inserting the other end of the lower hanger  612  into the other end of the upper hanger  611 . 
     The length adjusting part  70  may include a lower hanger insertion part  71 . The lower hanger insertion part  71  may be disposed at the other end of the upper hanger  611 . The lower hanger insertion part  71  and the upper hanger  611  may have a diameter or size larger than that of the lower hanger  612  so that the lower hanger  612  may be inserted into the lower hanger insertion part  71  of the length adjusting part  70 . The lower hanger  612  may move into the upper hanger  611  after being inserted into the lower hanger insertion part  71 . Although the lower hanger  612  is described as being inserted into the lower hanger insertion portion  71 , the configuration may be reversed and upper hanger  611  may be inserted into the lower hanger  612 . Although referred to as the lower hanger insertion portion  71 , in this embodiment, it may be referred to as a buckle for adjusting the insertion length of the lower hanger  612 . 
     The lower hanger insertion part  71  may include a lower hanger insertion hole  711 . The lower hanger insertion hole  711  may be an opening into which the lower hanger  612  may be inserted. The lower hanger insertion hole  711  may be formed to correspond to the lower hanger  612 . The lower hanger insertion hole  711  may extend from the lower hanger insertion part  71  to the inside of the upper hanger  611 . The lower hanger  612  inserted into the lower hanger insertion hole  711  may be inserted up to the inside of the upper hanger  611 . 
     A guide groove  72  may be provided on one surface of the lower hanger  612 . A plurality of guide grooves  72  may be inserted into the lower hanger insertion part  71  together with the lower hanger  612 . The plurality of guide grooves  72  may limit separation of the lower hanger  612  from the lower hanger insertion part  71 . The plurality of guide grooves  72  inserted into the lower hanger insertion part  71  may lock onto a protrusion provided in the lower hanger insertion part  71 . Thus, the user may adjust the length of the hanger body  61  by using a method in which the protrusion of the lower hanger insertion part  71  is fixed to the plurality of guide grooves  72  inserted into the lower hanger insertion part  71 . In the present embodiment, the plurality of guide grooves may be referred to as racks. 
     The length adjusting part  70  may include an adjusting switch  73 . The adjusting switch  73  may be provided on one side of the lower hanger insertion part  71 . The adjusting switch  73  may adjust whether the protrusion provided inside the lower hanger insertion part  71  is fixed to the plurality of guide grooves  72 . For example, when the adjusting switch  73  is operated, the protrusion fixed to any one of the guide grooves of the plurality of guide grooves  72  may be released. When the protrusion is released from the plurality of guide grooves  72 , the lower hanger  612  may be separated from the lower hanger insertion part  71 . The user may manipulate the adjusting switch  73  to separate the protrusion fixed to any one of the guide grooves  72  of the plurality of guide grooves  72 , thereby adjusting the length of the hanger body  61 . 
     When the length adjusting part  70  is provided to the catching part  60 , the length of the hanger body  61  may be freely adjusted. The mask device  2  may be in close contact with various faces of users by adjusting the length of the hanger body  61 . The upper hanger  611  may be extended or shortened from the lower hanger  612 , so that the mask device  2  may be easily worn on the user&#39;s ear. 
       FIG. 20  is a view showing a mask device according to a third embodiment of the present invention. 
     Some parts of the mask device according to the third embodiment of the present invention may be the same or similar as the mask device  1  according to the first embodiment. Therefore, parts being the same or similar as in the mask device  1  may be omitted from the description of the mask device  3  according to the third embodiment. Hereinafter, a specific part of the mask device  3  according to the third embodiment modified from the mask device  1  according to the first embodiment will be described. 
     Referring to  FIG. 20 , the mask device  3  according to the third embodiment of the present invention may include a mask body  10 , a first air cleaner  20 , and a second air cleaner  40 . The mask device  3  may include a fifth catching part  80  coupled to the first air cleaner  20 , and a sixth catching part  90  coupled to the second air cleaner  40 . The mask device  3  may include a coupling module  100  coupling the fifth catching part  80  and the sixth catching part  90  to each other. In the present embodiment, the fifth catching part  80 , the sixth catching part  90 , and the coupling module  100  may allow the mask body  10  to be supported by the user&#39;s head. Alternatively, the fifth catching part  80 , the sixth catching part  90 , and the coupling module  100  may allow the mask body  10  to be supported on a hat, a helmet, or the like on the user&#39;s head. 
     The fifth catching part  80  may include a fifth hanger body  81  forming a body. The first air cleaner  20  may be detachably mounted to the fifth hanger body  81 . One side of the fifth hanger body  81  may be coupled to the first air cleaner  20 . The other side of the fifth hanger body  81  may be coupled to the coupling module  100 . The fifth hanger body  81  may be formed in a ring or ring shape. The user&#39;s ear may be positioned inside the fifth hanger body  81  or the user&#39;s ear may not be positioned inside the fifth hanger body  81 . The fifth hanger body  81  may include a duct through hole, a through hole, a wire tube through hole, and a hook groove for mounting the first air cleaner  20 , which has been described in the first embodiment. 
     The other side of the fifth hanger body  81  may include a first connector  811 . The first connector  811  may be for coupling the fifth hanger body  81  to one side of the coupling module  100 . The first connector  811  may be detachably fixed to one side of the coupling module  100 . For example, one side of the coupling module  100  may be configured such that the first connector  811  is inserted and fixed thereto. The distance between the coupling module  100  and the mask body  10  may be adjusted by the insertion length of the first connector  811  inserted into one side of the coupling module  100 . In other words, the length of the fifth hanger body  81  may be adjusted in the longitudinal direction by the insertion length of the first connector  811  inserted into one side of the coupling module  100 . When the length of the fifth hanger body  81  is adjusted, the mask body  10  may be stably fixed to the user&#39;s head, helmet, hat, and the like. 
     The sixth catching part  90  may include a sixth hanger body  91  forming a body. The second air cleaner  40  may be detachably mounted to the sixth hanger body  91 . One side of the sixth hanger body  91  may be coupled to the second air cleaner  40 . The other side of the sixth hanger body  91  may be coupled to the coupling module  100 . The sixth hanger body  91  may be formed in a ring or ring shape. The user&#39;s ear may be positioned inside the sixth hanger body  91  or the user&#39;s ear may not be positioned inside the sixth hanger body  91 . The sixth hanger body  91  may include a duct through hole, a through hole, a wire tube through hole, and a hook groove for mounting the second air cleaner  40 . 
     The other side of the sixth hanger body  91  may include a second connector  911 . The second connector  911  may be coupling the sixth hanger body  91  to the other side of the coupling module  100 . The second connector  911  may be detachably fixed to the other side of the coupling module  100 . For example, the other side of the coupling module  100  may be configured such that the second connector  911  is inserted and fixed thereto. The distance between the coupling module  100  and the mask body  10  may be adjusted by an insertion length in which the second connector  911  is inserted into the other side of the coupling module  100 . In other words, the length of the sixth hanger body  91  may be adjusted in the longitudinal direction by the insertion length of the second connector  911  inserted into the other side of the coupling module  100 . When the length of the sixth hanger body  91  is adjusted, the mask body  10  may be stably fixed to the user&#39;s head, helmet, hat, and the like. 
     The coupling module  100  may include a coupling module body  101  forming a body. The coupling module  100  may couple one end of the fifth hanger body  81  and one end of the sixth hanger body  91 . 
     The coupling module body  101  may include a first connector inserting part  1011  into which the first connector  811  is inserted and a second connector inserting part  1012  into which the second connector  911  is inserted. The first connector inserting part  1011  may be disposed at one side of the coupling module body  101 , and the second connector inserting part  1012  may be disposed at the other side of the coupling module body  101 . The first connector  811  may be inserted into and fixed to the first connector inserting part  1011 , and the second connector  911  may be inserted into and fixed to the second connector inserting part  1012 . 
     The coupling module body  101  may include a first adjusting part  1013  and a second adjusting part  1014 . The first adjusting part  1013  may be a button for separating the first connector  811  inserted into and fixed to the first connector insertion part  1011 . The second adjusting part  1014  may be a button for separating the second connector  911  inserted into the second connector inserting part  1012  and fixed thereto. The first connector  811  and the second connector  911  may be fixed to the user&#39;s face according to the length being inserted into the first connector insertion part  1011  and the second connector insertion part  1012  through which the length may be adjusted. 
     The coupling module body  101  may include an auxiliary battery  105 . The auxiliary battery  105  may supply power to at least one of the first air cleaner  20  and the second air cleaner  40 . The auxiliary battery  105  may be detachably coupled to the coupling module body  101 . The coupling module body  101  may include a battery mounting groove  1015  in which the auxiliary battery  105  is mounted. 
     The battery mounting groove  1015  may be formed to correspond to a shape of the auxiliary battery  105 . The battery mounting groove  1015  may be formed by recessing a portion of the coupling module body  101 . The auxiliary battery  105  may be mounted in the battery mounting groove  1015  and mounted on the coupling module body  101 . 
     The coupling module body  101  may supply power of the auxiliary battery  105  to at least one of the first connector  811  and the second connector  911 . For example, at least one of the first connector  811  and the second connector  911  and the coupling module body  101  may be configured as a socket. When at least one of the first connector  811  and the second connector  911  is coupled to the coupling module body  101 , it may be electrically connected. Inside the fifth hanger body  81  and the sixth hanger body  91  are provided electrical wires for transmitting the power of the auxiliary battery  105  to the first air cleaner  20  and the second air cleaner  40 . 
     When the auxiliary battery  105  is mounted on the coupling module  100 , power may be additionally supplied to the mask device  3 . The operation time of the mask device  3  may be extended by the auxiliary battery  105 . Since the auxiliary battery  105  is disposed on the coupling module  100  which may be centered in the mask device  3 , the auxiliary battery  105  may not cause the weight of the mask device  3  from being unevenly balanced. In one embodiment, the battery  26  of the mask device  3  may be charged by using the auxiliary battery  105  or by consuming the power of the auxiliary battery  105 . 
     While preferred embodiments of the present invention have been described above with reference to the drawings, the present invention is not limited to the above-described embodiments, and it will be apparent to those skilled in the art that the embodiments of the present invention may be modified without departing from the spirit and scope of the present invention. It will be understood that modifications and variations are possible. Therefore, the scope of the present invention should not be defined by the described embodiments, but should be determined by the technical spirit described in the claims.