Patent Publication Number: US-2022226762-A1

Title: Air purifier and filter assembly thereof

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority of Taiwan Patent Application No. 110102382, filed on Jan. 21, 2021, the disclosure of which is incorporated herein by reference. 
     FIELD OF INVENTION 
     The present disclosure relates to the technical field of filtering, which particularly relates to an air purifier and a filter assembly thereof that integrate the function of a fire escape filter mask. 
     BACKGROUND OF INVENTION 
     According to statistics, nearly 80% of the fatal causes of fires are caused by dense smoke rather than direct contact with flames. Most of the reasons for death in fire are first inhaling toxic gas, and then being suffocated and losing unconsciousness. 
     For example, when a flame burns furniture and other objects, toxic gases are generated, resulting toxic gases in high concentrations in the dense smoke of the fire, especially carbon monoxide. After the toxic gas enters the human body, it quickly combines with red blood cells, making the blood unable to deliver oxygen, causing the human body to die due to lack of oxygen. 
     However, ordinary households rarely have smoke protection masks needed to escape from fire. The reason is that the existing smoke protection masks require a strong smoke filtering function and have an independently designed filter. Although ordinary households may have air purifiers, due to different functional orientations, filters with smoke protection functions cannot be directly used in the existing air purifiers. In the past, there were some single-function products, but they still need to be improved. 
     As a result, it is necessary to provide a technical solution different from the past to solve the problems existing in the conventional technology. 
     SUMMARY OF INVENTION 
     An object of the present disclosure is to provide an air purifier, so that a filter is suitable for different situations of ventilating for fixed-locations and being worn for protection from smoke. 
     Another object of the present disclosure is to provide a filter assembly, so that a filter is suitable for different situations of ventilating for fixed-locations and being worn for protection from smoke. 
     To achieve the above object, the present disclosure provides an air purifier. The air purifier comprises a housing comprising a casing and a shell being detachable from each other, wherein the casing comprises a venting portion, a cover comprising at least one breathable part, a filter assembly configured in a space defined by the casing and the cover, wherein the filter assembly comprises a transformable body and at least one filter, the transformable body comprises two passage portions, the filter is located between the two passage portions, the transformable body is configured to be transformable to change airflow through the filter, and the venting portion, the two passage portions, and the breathable part are coupled in fluid communication, and a fan disposed in the housing and configured to generate airflow. 
     In one embodiment of the present disclosure, the casing, the cover, and the filter assembly are configured to form a filter mask. 
     In one embodiment of the present disclosure, the transformable body comprises a frame and at least one deflector. The frame contains the filter inside, wherein the frame comprises at least one opening adjacent to at least one side of the filter. The at least one deflector is configured to pivotally connected to the frame, wherein the at least one deflector pivots relative to the frame toward a first rotation direction or a second rotation direction, so that the at least one opening is in an open state or a closed state to expose or cover the at least one side of the filter. 
     In one embodiment of the present disclosure, the filter assembly further comprises a sliding element and an elastic element. The sliding element is configured to slide along a guiding portion, wherein the guiding portion is perpendicular to a rotating shaft of the deflector; in response to the at least one opening in the closed state, the at least one deflector pivots toward the first rotation direction to expose the filter during the sliding element sliding and approaching the rotating shaft. The elastic element is configured to combine between the frame and the at least one deflector, wherein the at least one elastic element applies a pulling force to the at least one deflector in response to the at least one opening in the open state, the at least one deflector pivots toward the second rotation direction to cover the filter during the sliding element sliding away from the rotating shaft. 
     In one embodiment of the present disclosure, the guiding portion is disposed on one side of the frame, the sliding element comprises a combining portion, at least one arm, and a towing portion; the combining portion slidably combines the guiding portion, the at least one arm is provided at an end of the combining portion and located on at least one side of the combining portion, the at least one arm is configured to support the at least one deflector, and the towing portion is located at another end of the combining portion and stretches out of the cover. 
     In one embodiment of the present disclosure, one side of the frame is provided with a first joining portion, one end of the arm is provided with a second joining portion, one side of the deflector is provided with at least one third joining portion and a fourth joining portion, the at least one third joining portion is located between the fourth joining portion and the rotating shaft, the elastic element is disposed between the fourth joining portion and the first joining portion, and the second joining portion and the third joining portion are detachably coupled. 
     In one embodiment of the present disclosure, the guiding portion is configured as a strip flange, the combining portion is configured as an elongated groove coupled with the strip flange. 
     In one embodiment of the present disclosure, the filter assembly further comprises head fitting element including two ends, one end is coupled with the towing portion, and another end is coupled with the cover. 
     In one embodiment of the present disclosure, the at least on deflector comprises a first deflector and a second deflector, one of the two passage portions is integrated with the first deflector, and another of the two passage portions is separated from the second deflector. 
     In one embodiment of the present disclosure, the at least one filter comprises a single filter, the two passage portions are adjacent to two opposite sides of the filter, and the passage portions are adjacent to two opposite ends of the filter. 
     In one embodiment of the present disclosure, the at least one filter comprises a plurality of filters arranged side by side, one of the filters is defined as a specific filter, the two passage portions are adjacent to two opposite sides of the specific filter, and the passage portions are adjacent to two opposite ends of the specific filter. 
     In one embodiment of the present disclosure, the cover is provided with a face-fitting structure, and the breathable part is located in the face-fitting structure. 
     In one embodiment of the present disclosure, the face-fitting structure is provided with a skin contact portion. 
     To achieve the above object, the present disclosure provides a filter assembly. The filter assembly comprises a transformable body comprising two passage portions, and at least one filter located between the two passage portions, wherein the transformable body is configured to be transformable to change airflow through the filter. 
     In one embodiment of the present disclosure, the transformable body comprises a frame and at least one deflector. The frame contains the filter inside, wherein the frame comprises at least one opening adjacent to at least one side of the filter. The at least one deflector is configured to pivotally connected to the frame, wherein the at least one deflector pivots relative to the frame toward a first rotation direction or a second rotation direction, so that the at least one opening is in an open state or a closed state to expose or cover the at least one side of the filter. 
     In one embodiment of the present disclosure, the filter assembly further comprises a sliding element and an elastic element. The sliding element is configured to slide along a guiding portion, wherein the guiding portion is perpendicular to a rotating shaft of the deflector, in response to the at least one opening in the closed state, the at least one deflector pivots toward the first rotation direction to expose the filter during the sliding element sliding and approaching the rotating shaft. The elastic element is configured to combined between the frame and the at least one deflector, wherein the at least one elastic element applies a pulling force to the at least one deflector in response to the at least one opening in the open state, and the at least one deflector pivots toward the second rotation direction to cover the filter during the sliding element sliding away from the rotating shaft. 
     In one embodiment of the present disclosure, the guiding portion is disposed on one side of the frame, the sliding element comprises a combining portion, at least one arm, and a towing portion; the combining portion slidably combines with the guiding portion, the at least one arm is provided at an end of the combining portion and located on at least one side of the combining portion, the at least one arm is configured to support the at least one deflector, and the towing portion is located at another end of the combining portion. 
     In one embodiment of the present disclosure, one side of the frame is provided with a first joining portion, one end of the arm is provided with a second joining portion, one side of the deflector is provided with at least one third joining portion and a fourth joining portion, the at least one third joining portion is located between the fourth joining portion and the rotating shaft, the elastic element is disposed between the fourth joining portion and the first joining portion, and the second joining portion and the third joining portion are detachably coupled. 
     In one embodiment of the present disclosure, the guiding portion is configured as a strip flange, the combining portion is configured as an elongated groove coupled with the strip flange. 
     In one embodiment of the present disclosure, the at least on deflector comprises a first deflector and a second deflector, one of the two passage portions is integrated with the first deflector, and another of the two passage portions is separated from the second deflector. 
     In one embodiment of the present disclosure, the at least one filter comprises a single filter, the two passage portions are adjacent to two opposite sides of the filter, and the passage portions are adjacent to two opposite ends of the filter. 
     In one embodiment of the present disclosure, the at least one filter comprises a plurality of filters arranged side by side, one of the filters is defined as a specific filter, the two passage portions are adjacent to two opposite sides of the specific filter, and the passage portions are adjacent to two opposite ends of the specific filter. 
     The air purifier and the filter assembly thereof according to the present disclosure, the filter assembly includes a transformable body and at least one filter. The transformable body is provided with two passage portions, the filter is located between the two passage portions, and the transformable body is configured to be transformable to change the flow rate of air flowing through the filter. Therefore, the filter is suitable for different situations of fixed-location ventilation and smoke protection. The transformable body covers the filter and is used as an escape filter mask. The transformable body reveals the filter and is used in an air purifier, so that the air purifier may integrate the function of an escape filter mask for emergency needs. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a schematic diagram of an air purifier according to an embodiment of the present disclosure. 
         FIG. 2  is a schematic diagram of an escape filter mask of the air purifier according to an embodiment of the present disclosure. 
         FIG. 3  is an exploded schematic diagram of the escape filter mask in  FIG. 2 . 
         FIG. 4  is an exploded schematic diagram of a filter assembly composed of a single filter according to an embodiment of the present disclosure. 
         FIG. 5A  is a schematic diagram of the filter in  FIG. 4  in a purifier mode. 
         FIG. 5B  is a schematic diagram of an airflow direction of the filter in  FIG. 5A . 
         FIG. 6A  is a schematic diagram of the filter in  FIG. 4  in a smoke filter mode. 
         FIG. 6B  is a schematic diagram of an airflow direction of the filter in  FIG. 6A . 
         FIG. 7  is a schematic diagram of use of the escape filter mask according to an embodiment of the present disclosure. 
         FIG. 8A  is a schematic diagram ( 1 ) of a filter assembly composed of several filters in the purifier mode according to an embodiment of the present disclosure. 
         FIG. 8B  is a schematic diagram ( 2 ) of a filter assembly composed of several filters in the purifier mode according to an embodiment of the present disclosure. 
         FIG. 9A  is a schematic diagram ( 1 ) of a filter assembly composed of several filters in the smoke filter according to an embodiment of the present disclosure. 
         FIG. 9B  is a schematic diagram ( 2 ) of a filter assembly composed of several filters in the smoke filter according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The structure and the technical means adopted by the present disclosure to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings. Furthermore, directional terms described by the present disclosure, such as upper, lower, front, back, left, right, inner, outer, side, longitudinal/vertical, transverse/horizontal, etc., are only directions by referring to the accompanying drawings, and thus the used directional terms are used to describe and understand the present disclosure, but the present disclosure is not limited thereto. 
     Referring to  FIG. 1  to  FIG. 3 , one aspect of present disclosure provides an air purifier. The air purifier comprises a housing  1 , a cover  2 , and a filter assembly  3 . The housing  1  is used to install the cover  2  and the filter assembly  3 , but not limited to this. The housing  1  is also used to install a fan  4 , such as an axial flow fan or a blower fan, etc., to assist in generating airflow. The following examples illustrate the implementation of the above-mentioned embodiment of the air purifier of the present disclosure, but it is not limited thereto. 
     Referring to  FIG. 1  to  FIG. 3 , the housing  1  may be made of plastic. The housing  1  may be composed of multiple components. For example, the housing  1  includes a casing  1   a  and a shell  1   b . For example, the casing  1   a  has a chamber  11 , a venting portion  12 , and a holding port  13 . The chamber  11  accommodates the filter assembly  3 , the venting portion  12  and the holding port  13  are connected to the chamber  11 , and the holding port  13  is combined with the cover  2 . The casing  1   a  and the shell  1   b  may be assembled into a specific type of housing. It should be understood that the housing has a portion for letting air in and out. For example, the venting portion  12  of the casing  1   a  may be used as a first air portion. The shell  1   b  is also be provided with a through hole portion (not shown in the figures, such as formed by a plurality if through holes) as a second air portion to assist the passage of air. Thereby, the housing of the air purifier may be composed of multiple components for disassembly, repair, or maintenance operations. 
     Optionally, in an embodiment, as shown in  FIG. 1 , the housing  1  is also provided with a control unit  14 , for example, the control unit  14  is configured as a control module. The control unit  14  includes a microcontroller and a human-machine interface (such as a touch panel or a combination of buttons and a display). The control unit  14  is also electrically connected to other electrical components, such as power components (such as fans or motors, etc.), power supply sources (such as wires or batteries, etc.), communication units (such as wired or wireless communication transceivers, etc.) and specific functions components (such as negative ion generators, etc.), as the basis for regulating the operation mode of the air purifier. In the embodiment, the control unit  14  is disposed on the shell  1   b , and the control unit  14  is electrically connected to the fan  4 , but is not limited to this. The fan  4  may also be directly connected to an external power source. As a result, the control unit can centrally control the operation modes of the air purifier, such as start, stop, air volume, timing, and operation mode settings. 
     Optionally, in an embodiment, as shown in  FIG. 1 , the partial structure of the housing  1  is also configured into a structure that makes it easy to take out the internal articles. For example, a part of the shell  1   b  is mortised to form a liftable portion  15  so as to cover and remove a part of the casing  1   a  and its combined components, such as the cover  2  and the filter assembly  3 , but not limited to this. In this way, it is convenient to move and take out the components containing the filter assembly, so as to facilitate the use and maintenance. 
     Optionally, in an embodiment, as shown in  FIG. 2 , the housing  1   a , the cover  2 , and the filter assembly  3  are configured to form a filter mask, for example, the filter assembly  3  is located in the chamber  11  of the housing  1   a , and the filter assembly  3  is combined with the cover  2 . The cover  2  is detachably coupled to the holding port  13  of the housing  1   a , so that the above-mentioned embodiment implicitly includes the filter mask, which may be taken out from the air purifier in specific situations. For example, separating the casing  1   a  forming the filter mask from the shell  1   b  not belonging to the filter mask facilitates emergency escape and other purposes. 
     Optionally, in an embodiment, as shown in  FIG. 3 , the housing  1  is also provided with at least one partition  16  which divides the chamber  11  into several compartments. For example, one of the compartments may accommodate the filter assembly  3 . In this way, in addition to making good use of the space inside the housing, different types of objects may be isolated to avoid interference of different functional elements during operation. 
     Referring to  FIG. 3 , the cover  2  may be made of plastic. For example, the cover  2  is detachably coupled to the holding port  13  of the housing  1 . For example, by detachably combining bolts and screw holes, the cover  2  may be provided with a breathable part  21 . The breathable part  21  is configured into a shape suitable for nostril breathing. For example, the breathable part  21  is configured as two breathable holes in a face-fitting structure  2   a . For example, each breathable hole may be equipped with a filter, so that the user may inhale or exhale air through the breathable part  21 . No limited to this, for example, the face-fitting structure  2   a  may also be provided with a skin contact portion  22 , such as a ring-shaped flexible material (such as a cotton pad, etc.), so as to improve the user&#39;s face contact comfort. Not limited to this, the cover  2  is also be provided with a vent  23  to assist in the passage of air. 
     Referring to  FIG. 3  to  FIG. 4 , the filter assembly  3  is composed of plastic and filter elements to form an air filter assembly, and the filter assembly  3  is arranged in a space defined by the casing  1   a  and the cover  2 . For example, the filter assembly  3  is placed in the chamber  11  of the housing  1 , and the filter assembly  3  is detachably combined with the cover  2 , For example, it can be detachably combined with bolts and screw holes. The filter assembly  3  includes a transformable body  31  and at least one filter  32 , and the filter  32  has an air filtering function. For example, the filter  32  may be at least one pleated filter made of randomly arranged chemical fibers or glass fibers, such as a high-efficiency particulate air filter (H EPA) but is not limited thereto. 
     Referring to  FIG. 3  to  FIG. 4 , the transformable body  31  may be made of plastic, and, for example, the transformable body  31  is provided with two passage portions  311  and  312 . It should be understood that in this example, the number of the passage portions is only two for air in and out as an example, but is not limited to this, the passage portions may also be modified into other shapes as required. For example, a single passage portion (such as the passage portion  311  or passage portion  312 ) may be split into multiple sub-passage portions (such as through holes), for air to flow into or out of the filter  32 . For example, the filter  32  is provided between the two passage portions  311  and  312  of the transformable body  31 . The transformable body  31  is configured to be transformable. For example, the transformable body  31  may be provided with at least one gate formed by at least one movable member (such as a plate body, a sheet body, a cover body and/or a membrane body, etc.) to expose or cover at least a part of the filter  32  to change the air flow through the filter  32 . The venting portion  12 , the two passage portions  311 ,  312 , and the breathable part  21  are configured to be coupled in fluid communication. For example, the passage portions  311  and the venting portion  12  are close to each other to be coupled with each other. An air guide  312   a  (such as a tube body, a cover body, or a combination thereof) may be used between the breathable part  21  and the passage portion  312  to couple with each other, but is not limited to this, so that the air can in communication with each other. 
     Referring to  FIG. 3 , in an airflow path passing through the filter assembly  3 , for example, the airflow path formed by the venting portion  12  of the housing  1 , the two passage portions  311  and  312  of the filter assembly  3 , and the breathable part  21  of the cover  2 , or the air flow path formed by the venting portion  12 , the filter assembly  3 , and the vent  23  may be controlled by the fan  4 . For example, the fan  4  may be arranged in the housing  1 , such as near the venting portion  12 , but not is limited to this. The fan  4  is also be adapted to be arranged near the cover  2  or the filter assembly  3  for generating air flow through the filter  32 . 
     The air passing through the air flow path may be filtered by the filter. When the transformable body is configured to transform to reveal the filter, the flow of air filtered through the filter may be increased to adapt to different usage scenarios, such as an air purifier with a fixed-location ventilation function or an escape filter with a smoke protection protection function. 
     Optionally, in an embodiment, as shown in  FIG. 3  and  FIG. 4 , in the filter assembly  3 , the transformable body  31  includes, for example, a frame  313  and at least one deflector  314 . For example, the frame  313  may be made of plastic, and the filter  32  may be accommodated in the frame  313 . For example, the frame  313  may be formed with a structure (such as a groove, etc.) for accommodating the filter  32  and structures used to guide airflow (such as windows, holes, or pipes, etc.). The frame  313  may also have at least one opening  313   a , and the at least one opening  313   a  is adjacent to at least one side  32   s  (for example, a filter side) of the filter  32 . The at least one opening  313   a  allows at least one side  32   s  of the filter  32  to be exposed, allowing air to flow into the filter  32  or out of the filter  32  through the at least one opening  313   a . For example, the at least one deflector  314  may be made of plastic. The specifications (such as size and shape, etc.) of the at least one deflector  314  and the at least one opening  313   a  are compatible with each other, and the at least one deflector  314  is configured to be pivotally connected to the frame  313 . For example, a rotating shaft and a shaft hole structure that may pivot to each other are used, the at least one deflector  314  may pivot relative to the frame  313  toward a first rotation direction (for example, counterclockwise), so that the at least one deflector  314  is opposite to each other. The at least one opening  313   a  is opened to form at least one opened gate. The at least one opening  313   a  is in an open state (as shown in  FIG. 5A ) to reveal the at least one side  32   s  of the filter  32 . The at least one deflector  314  and the at least one opening  313   a  may jointly form at least one air guide portion. For example, the more the at least one deflector  314  pivots away from the filter  32 , the more air may be guided to filter through the filter  32 . On the other hand, the at least one deflector  314  may pivot in a second rotation direction (for example, clockwise) relative to the frame  313 , so that the at least one deflector  314  is covered back relative to the at least one opening  313   a  to form at least one closed gate. As a result, the at least one opening  313   a  is in a closed state (as shown in  FIG. 6A ) to cover the at least one side  32   s  of the filter  32 , so that air may be repeatedly filtered through the filter  32 . 
     Since the at least one deflector is configured to be able to pivot in different directions relative to the frame, the at least one opening is in the open state or the closed state. The air flow of the filter is adjusted according to different usage requirements to adapt to different usage scenarios. 
     In an embodiment, as shown in  FIG. 4  and  FIG. 5A , a single filter  32  is taken as an example. The filter  32  has both air cleaning and fire and smoke protection functions. For the convenience of description, the at least one deflector  314  includes a first deflector  314 A and a second deflector  314 B. The two passage portions  311  and  312  are a first passage portion  311  and a second passage portion  312 , and the first passage portion  311  and the first deflector  314 A may be integrated with each other. The first passage portion  311  is adjacent to one end  32   e   1  of the filter  32 , and the second passage portion  312  and the second deflector  314 B may be separated from each other. The second passage portion  312  is adjacent to the other end  32   e   2  of the filter  32 , and, for example, the first passage portion  311  and the second passage portion  312  are respectively adjacent to two opposite sides  32   s   1 ,  32   s   2  of the filter  32 . The second passage portion  312  and the first passage portion  311  are respectively adjacent to the opposite ends  32   e   1 ,  32   e   2  of the filter  32 , so that the filter  32  may filter air at a larger portion but is not limited thereto. Thereby, the air passing through the filter may be filtered to the greatest extent, so as to improve the filtering effect. 
     As shown in  FIG. 5A , when the two sides (such as the upper and lower sides) of the filter  32  are exposed, the first deflector  314 A and the second deflector  314 B respectively pivot towards the two openings  313   a  away from the frame  313 , so that the two openings  313   a  can be in the open state. The two openings  313   a  may guide air through the first deflector  314 A and the second deflector  314 B, so that a large amount of airflow may flow longitudinally through the filter  32  in a large-area filtering manner (as shown in  FIG. 5B ). Multiple arrows exemplarily indicate the directions of the airflow, which may also be the opposite directions, to improve the ventilation efficiency, so that the filter assembly  3  is in a purifier mode, for example, it may be adapted to be configured for an air purifier. As shown in  FIG. 6A , when the two sides (such as the upper and lower sides) of the filter  32  are covered, for example, the first deflector  314 A and the second deflector  314 B respectively pivot toward the two openings  313   a  of the frame  313 , so that the two openings  313   a  may be in the closed state. The air may flow through the filter  32  from the two passage portions ( 311  as shown in the figure) and the surrounding air guide ( 312   a  as shown in the figure), allowing an appropriate amount of air flow through the filter  32  in a repeated filtering manner (as shown in  FIG. 6B , multiple arrows exemplarily indicate the directions of the air flow, and the directions of the air flow may also be the opposite directions) to improve the filtering effect. The filter assembly  3  is in a smoke filter mode. For example, it can be adapted to be configured as an escape filter mask. The structure of the filter assembly  3  to switch between different modes is illustrated as an example below but is not limited to this. 
     For example, as shown in  FIG. 3  and  FIG. 4 , the filter assembly  3  further include a sliding element  315  and at least one elastic element  316  for making the at least one opening  313   a  in the open state or the closed state. The sliding element  315  may be configured to slide along a guiding portion  313   b , for example, the guiding portion  313   b  is perpendicular to a rotating shaft  314   a  of the deflector  314 . The at least one opening  313   a  is in the closed state. During the sliding element  315  sliding and approaching the rotating shaft  314   a , the at least one deflector  314  pivots toward the first rotation direction to be away from the opening  313   a  until the at least one deflector  314  is supported by the sliding element  315 , the at least one opening  313   a  is in the open state to reveal the filter  32 . In addition, the at least one elastic element  316  may be configured to be combined between the frame  313  and the at least one deflector  314 . The elastic element  316  is an elastic element (such as a tension spring, etc.) that may be extended to provide tension, and the at least one opening  313   a  is in the open state. The at least one elastic element  316  is elongated, so that the at least one elastic element  316  may provide a pulling force to the at least one deflector  314 . During the sliding element  315  sliding away from the rotating shaft  314   a , the at least one deflector  314  pivots toward the second steering to approach the opening  313   a  until the at least one deflector  314  is blocked by the frame  313 , and the at least one opening  313   a  is in the closed state to cover the filter  32 . 
     Optionally, in an embodiment, as shown in  FIG. 3  and  FIG. 4 , The guiding portion  313   b  is provided on one side of the frame  313 , and the guiding portion  313   b  is configured as a strip-shaped flange or the like to form a track capable of guiding the sliding element  315  to slide. The sliding element  315  has a combining portion  315   a , at least one arm  315   b , and a towing portion  315   c . The combining portion  315   a  is configured as an elongated groove. The elongated groove may extend from one end of the sliding element  315  to the inside of the sliding element  315 . The elongated groove is slidably combined with the strip flange, so that the sliding element  315  may slide back and forth along the track of the guiding portion  313   b . The at least one arm  315   b  is provided at an end of the combining portion  315   a  and located on at least one side of the combining portion  315   a , and the at least one arm  315   b  is configured to support the at least one deflector  314 . For example, the two arms  315   b  are located on both sides of the combining portion  315   a  and are used to support the two deflectors  314 . The towing portion  315   c  (for example, forming a ring or hook, etc.) is located at the other end of the combining portion  315   a . The towing portion  315   c  may extend through the cover  2 , the sliding element  315  may be moved away from the rotating shaft  314   a  by external pulling force, or the sliding element  315  may be moved closer to the rotating shaft  314   a  by the elastic element  316  exerting a pulling force. Thereby, the sliding element may use the combining portion to slide along the guiding portion, so that the at least one opening is in the closed state or the open state. 
     Optionally, in an embodiment, as shown in  FIG. 4 , one side of the frame  313  is provided with a first coupling portion  313   c  (such as a hook, etc.), and one end of the arm  315   b  is provided with a second coupling portion  315   d  (such as a guide groove). At least one third coupling portion  314   b  (such as a bump, etc.) and a fourth coupling portion  314   c  (such as a bump, etc.) are provided on one side of the deflector  314 . The at least one third coupling portion  314   b  is located between the fourth coupling portion  314   c  and the rotating shaft  314   a . Taking several third coupling portions as an example, the several third coupling portions may be located equidistantly between the fourth coupling portion  314   c  and the rotating shaft  314   a , so as to adjust the deflector  314  to show a different degree of opening relative to the frame  313 . As shown in  FIG. 5A  and  FIG. 6A , the movement of the arm  315   b  may be designed to be limited by the third coupling portion  314   b  and the fourth coupling portion  314   c . The elastic element  316  is provided between the fourth coupling portion  314   c  and the first coupling portion  313   c , and two ends of the elastic element  316  are detachably fixed between the fourth coupling portion  314   c  forming the protrusion and the first coupling portion  313   c  forming the hook body. The second coupling portion  315   d  and the third coupling portion  314   b  are detachably coupled. For example, the third coupling portion  314   b  forming the protrusion and the second coupling portion  315   d  forming the guide groove are engaged with each other, but is not limited thereto. 
     When the deflector is pushed to make the at least one opening in the open state, the elastic element provides the pulling force required to restore the closed state. The third coupling portion forming the bump is moved away from the second coupling portion forming the guide groove, and the deflector may be covered by the pulling force to cover the opening. As a result, the overall movable structure may be simplified to reduce manufacturing costs and maintenance difficulty. 
     In one embodiment, as shown in  FIG. 2  and  FIG. 7 , the air purifier also includes a head fitting element  5 , such as a rubber belt body, etc., the head fitting element  5  has two ends, one of which is connected to the towing portion  315   c , and the other end is connected to a suitable coupling portion  24  (such as a ring body or a hook body, etc.) of the cover  2 . The user may use the head fitting element to firmly combine the escape filter mask containing the housing, the filter assembly, and the cover on the face, so as not to be easily loosened and to reliably perform breathing and ventilation through the filter assembly. 
     Optionally, in addition to pulling the sliding element through the head fitting element, the actuation method of the sliding element may also be carried out electrically. For example, a linear motor may be arranged near the sliding element, the linear motor may be controlled (for example, controlled by a microcontroller, etc.), so that the linear motor may be extended and contracted to cause the sliding element to slide by pushing or pulling, but not limited to this. Thereby, the linear motor may be used to adjust the degree of opening of the deflector relative to the frame. 
     Referring to  FIG. 1 , in general use, the user operates the above-mentioned embodiment as a fixed-location ventilation function. For example, the filter assembly  3  may be in the purifier mode, and the two openings  313   a  of the frame  313  are in the open state (as shown in  FIG. 5A ), so that a large amount of airflow flows longitudinally through the filter  32  (as shown in  FIG. 5B ) in the large-area filtering manner to improve the ventilation efficiency. On the other hand, in the case of emergency filtering of poisonous gas, such as a fire, the user may operate the above embodiment in a smoke-proof situation. For example, the filter assembly  3  may be in the smoke filter mode. The filter mask formed by the configuration of the housing  1   a , the cover  2  and the filter assembly  3  may be separated from the shell  1   b  and taken out separately (as shown in  FIG. 2 ). As shown in  FIG. 7 , the head fitting element  5  may be pulled and secured to a user&#39;s head H. The towing portion  315   c  may be pulled to extend the cover  2 , so that the filter assembly  3  is in the smoke filter mode. The two deflectors  314  abut the edges of the two openings  313   a , so that the two openings  313   a  of the frame  313  are in the closed state (as shown in  FIG. 5A  and  FIG. 6A ). A proper amount of airflow flows laterally through the filter  32  (as shown in  FIG. 6B ) in the repeated filtering manner to improve the filtering effect, so that the user may breathe the repeatedly filtered air. 
     In another embodiment, the number of filters in the filter assembly may also be several, as shown in  FIG. 8A ,  FIG. 8B ,  FIG. 9A , and  FIG. 9B . One filter assembly  3 ′ may be used to replace the above-mentioned filter assembly  3 . The difference between the two filter assemblies  3  and  3 ′ is mainly explained. The number of filters and correspondingly changed passage portions and deflectors, etc., the remaining components of the filter assembly  3 ′ are the same as the above-mentioned filter assembly  3  or have corresponding functions. The filter assembly  3 ′ includes a transformable body  31 ′ and several filters. Taking two filters as an example, the filter assembly includes a first filter  32   a ′ and a second filter  32   b ′. The second filter  32   b ′ may be a specific filter with a fire alarm and smoke protection function. The first filter  32   a ′ has an air purifier function, but is not limited to this. The transformable body  31 ′ may be provided with appropriate partitions or compartments for separately disposing the first filter  32   a ′ and the second filter  32   b ′. The transformable body  31 ′ is provided with a first passage portion  311 ′, a second passage portion  312 ′, two openings  313   a ′, a first deflector  314 A′, and a second deflector  3146 ′. The first deflector  314 A′, the second deflector  3146 ′, and the two openings  313   a ′ are compatible with each other. Taking the side-by-side arrangement of the first filter  32   a ′ and the second filter  32   b ′ as an example, the areas of the two openings  313   a ′ may be different (but may also be the same). The two openings  313   a ′ are adjacent to the two side portions formed together of the first filter  32   a ′ and the second filter  32   b ′. For any side, one of the two openings  313   a ′ may be opened or closed, for example, to expose or cover the entire side of the first filter  32   a ′ and the partial side of the second filter  32   b ′. In addition, the first passage portion  311 ′ and the second passage portion  312 ′ are adjacent to one of the two filters, and, for example, are adjacent to opposite ends of the second filter  32   b ′. The first passage portion  311 ′ is adjacent to one end  32   b   1 ′ of the second filter  32   b ′, and the second passage portion  312 ′ is adjacent to the other end  32   b   2 ′ of the second filter  32   b ′. The first passage portion  311 ′ and the first deflector  314 A′ may be integrated with each other (as shown in  FIG. 8A ). The second passage portion  312 ′ and the second deflector  314 B′ may be separated from each other (as shown in  FIG. 8B ). 
     For example, as shown in  FIG. 8A  and  FIG. 8B , when the two sides (such as upper and lower sides) of the first filter  32   a ′ and the second filter  32   b ′ are exposed, the two openings  313   a ′ are in the open state. A large amount of airflow may be provided to flow longitudinally through the first filter  32   a ′ and the second filter  32   b ′ in the large-area filtering manner to improve the ventilation efficiency and make the filter assembly  3 ′ in the purifier mode. For example, as shown in  FIG. 9A  and  FIG. 9B , when the two sides (such as upper and lower sides) of the first filter  32   a ′ and the second filter  32   b ′ are covered, the two openings  313   a ′ are in the closed state. Air may flow through the second filter  32   b ′ from the two passage portions  311 ′ and  312 ′, allowing a proper amount of air flow to flow laterally through the second filter  32   b ′ in the repeated filtering manner. Air may flow-in from the first passage portion  311 ′, and then flow-out from the second passage portion  312 ′ to improve the filtering effect, so that the filter assembly  3 ′ is in the smoke filter mode. 
     On the other hand, the present disclosure also provides a filter assembly. The implementation and effects of the filter assembly have been described above and will not be repeated. 
     The air purifier and the filter assembly thereof according to the above-mentioned embodiment of the present disclosure, the filter assembly includes a transformable body and at least one filter. The transformable body is provided with two passage portions, the filter is located between the two passage portions, and the transformable body is configured to be transformable to change the flow rate of air flowing through the filter. Therefore, the filter is suitable for different situations of fixed-location ventilation and smoke protection. The transformable body covers the filter and is used as an escape filter mask. The transformable body reveals that the filter is used in an air purifier, so that the air purifier may integrate the function of an escape filter mask for emergency needs. 
     Although the present disclosure has been disclosed in preferred embodiments, it is not intended to limit the present invention. Anyone who is familiar with this technique may make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be subject to the definition of the attached patent scope.