CN111701158A

CN111701158A - Electric breathing equipment and air filtering device thereof

Info

Publication number: CN111701158A
Application number: CN202010704664.1A
Authority: CN
Inventors: 吴子乾
Original assignee: Tekman Nanjing Electronics Co ltd
Current assignee: Tecman Nanjing Safety Protection Equipment Co ltd
Priority date: 2020-07-21
Filing date: 2020-07-21
Publication date: 2020-09-25

Abstract

The application discloses an electric breathing equipment and an air filtering device thereof, wherein the air filtering device comprises a main machine, the main machine comprises a shell; and an air filter cartridge detachably connected to the host, the housing including an interface surface facing the air filter cartridge when the host is connected to the air filter cartridge, the housing of the air filter cartridge including a filter screen surface facing the host when the host is connected to the air filter cartridge, the housing of the host further including a first set of hall sensors positioned in the interface surface, the first set of hall sensors including N hall sensors spaced from each other, wherein N is an integer greater than or equal to 2, the housing of the air filter cartridge further comprises N alignment positions in the screen face, when the filtration box is connected with the shell of the host machine, N alignment positions are respectively aligned with N Hall sensors, the filtration box comprises one or N magnetic pieces selectively arranged at the N alignment positions, and the arrangement mode of the magnetic pieces at the N alignment positions corresponds to the operation mode of the host machine for the filtration box.

Description

Electric breathing equipment and air filtering device thereof

Technical Field

The present application relates generally to electrically powered breathing apparatus, and more particularly to air filtration devices for electrically powered breathing apparatus.

Background

The electric breathing equipment is used as a component of a life environment supporting system and widely applied to various harmful occasions, so that a user can safely and reliably breathe clean air at sites harmful to human health, such as severe welding work sites or even emergency medical diagnosis sites with respiratory disease infection risks.

The electric breathing equipment generally comprises a main machine which can be worn on the waist of a human body, a filter box which is detachably arranged on the main machine, a breathing mask (a welding mask for a welding field), and a connecting pipe which is positioned between the main machine and the breathing mask. Ambient air is filtered and sucked into the main machine through the filter box under the driving of components in the main machine, and then is supplied to the breathing mask through the connecting pipe for the user to inhale.

The filter cassette, as a consumable, must be replaced after a certain period of use. However, in the case where the filter cassette is not mounted in place although it is mounted to the main unit, there is a high possibility that air that is not effectively filtered is sucked into the main unit and sucked by a user through the connection pipe, resulting in impaired health. In busy construction or work sites, it is often not time for a user to check that the filter cassette is in place after it is installed on the host machine, and so it is desirable to avoid this. Otherwise, if the connection pipe is not installed in place with the main unit and the main unit is started up, harmful air is breathed into the user, and health is damaged.

In addition, after the user purchases the electric breathing apparatus, the user may need to work in different working occasions. Because different filter cartridges need to be equipped in different operation occasions and the operation mode of the host needs to be reset correspondingly for different filter cartridges, users are often required to manually adjust the configuration of the host. This puts high demands on the operating skill of the user, and is not favorable for the user to equip the electric breathing equipment to quickly adapt to the changing working occasions.

Disclosure of Invention

To above problem, the present application provides an improved electronic respiratory equipment to can ensure that each component part of electronic respiratory equipment can only start under the prerequisite of installing each other to take one's place, and can adjust the mode of operation of host computer automatically after the different filter cartridges are assembled, bring very big convenience for the user.

According to an aspect of the present application, there is provided an air filtering device of a powered breathing apparatus, comprising:

the host comprises a shell, and an electric fan is arranged in the shell; and

an air filter cartridge detachably connected to the host, the housing of the host including an interface facing the air filter cartridge when the host is connected to the air filter cartridge, the air filter cartridge having a housing including a screen surface facing the host when the host is connected to the air filter cartridge, the housing of the host further including a first set of hall sensors located in the interface, the first set of hall sensors including N hall sensors spaced apart from each other, where N is an integer greater than or equal to 2, the housing of the air filter cartridge further including N aligning positions located in the screen surface, the N aligning positions being aligned with the N hall sensors respectively when the air filter cartridge is connected to the housing of the host, the air filter cartridge including one or N magnetic members selectively provided at the N aligning positions, the arrangement mode of the magnetic pieces at the N alignment positions corresponds to the operation mode of the host machine for the air filter box.

Optionally, the magnetic member has 2 in the N alignment positions^N1 arrangement.

Optionally, the hall sensor is hidden in a housing of the host; and/or the magnetic member is disposed concealed within a housing of the air filtration cassette.

Optionally, the housing of the host further comprises a second set of hall sensors in the interface, the second set of hall sensors comprising at least one hall sensor, and the housing of the air-filter cartridge further comprises at least one additional alignment position in the screen face, the at least one additional alignment position being aligned with the hall sensors of the second set of hall sensors respectively when the air-filter cartridge and the host are mounted in place, one additional magnet being provided at each of the at least one additional alignment positions, respectively.

Optionally, the housing of the host machine includes a ring of first flanges around the interface, and the housing of the air filtration cassette includes a ring of second flanges around the screen face, the first flanges fully contacting the second flanges when the air filtration cassette is in place with the host machine.

Optionally, the first set of hall sensors and/or the second set of hall sensors are located within an area surrounded by the first flange, and/or the N alignment positions and/or the at least one additional alignment position are located within an area surrounded by the second flange.

Optionally, the air filtering device further includes a connection port to detachably connect with a joint of a connection hose of the electrical breathing apparatus, the connection port is configured with a third group of hall sensors, the third group of hall sensors includes at least one hall sensor, the joint includes at least one additional alignment position, when the joint and the connection port are installed in place, the at least one additional alignment position of the joint is respectively aligned with the hall sensors of the third group of hall sensors, and an additional magnetic member is correspondingly disposed at each of the at least one additional alignment position of the joint.

Optionally, the magnetic member comprises magnetic beads or magnetic flakes made of a permanent magnetic material.

According to another aspect of the present application, there is also provided an air filtering device of a powered breathing apparatus, comprising:

the host comprises a shell, and an electric fan is arranged in the shell; and

with the air filter cartridge that the host computer can dismantle ground and link to each other, the shell of host computer includes the host computer with when air filter cartridge links to each other the orientation interface of air filter cartridge, air filter cartridge has the shell, air filter cartridge's shell includes the host computer with when air filter cartridge links to each other the orientation screen face of host computer, the shell of host computer still includes to be located first set of proximity switch in the interface, first set of proximity switch includes N proximity switch of interval each other, and wherein, N is the integer more than or equal to 2, air filter cartridge's shell still includes to be located N in the screen face is to the position, when air filter cartridge with the shell of host computer links to each other, N is to the position with N proximity switch is respectively to the position, air filter cartridge include in N is to one or N that the position selectively set up of adjusting to the position department can with the cooperation of proximity switch interact A counterpart, the counterpart being arranged at the N registration positions in a manner corresponding to a manner in which the host computer operates with respect to the air filtration cassette.

According to another aspect of the present application, there is also provided a motorized breathing apparatus, comprising:

the aforementioned air filtration device;

a respiratory mask; and

a connection hose connected between the respirator and the air filtration device.

According to another aspect of the present application, there is also provided an operating method of the air filter device according to the foregoing, including:

connecting the air filter box with a host;

on the premise that N aligning positions of the air filter box are respectively aligned with N Hall sensors of a first group of Hall sensors of the host, wherein N is an integer greater than or equal to 2, monitoring the condition that magnetic parts exist at the N aligning positions by using the N Hall sensors;

comparing the monitoring result with the distribution condition of the magnetic pieces stored in advance to determine the type of the air filter box;

based on the model of the air filtration cartridge, the operating mode of the host is modified.

Optionally, after connecting the air filtration cassette to the host computer and before determining the model of the air filtration cassette, monitoring whether a second set of hall sensors of the host computer are aligned with additional magnetic members of the air filtration cassette in additional alignment positions to determine whether the air filtration cassette is in place on the host computer.

Optionally, if the air filtration cassette is not in place on the host computer, an alarm is raised and/or operation of the host computer is stopped.

Adopt above-mentioned technical means of this application, not only can ensure that whether filtration box and host computer, coupling hose and air filter install in place, thereby the operation mode of the model resetting host computer that can also automatic identification filtration box has improved the use reliability and the convenience of the electronic breathing equipment of this application.

Drawings

The principles and aspects of the present application will be more fully understood from the following detailed description, taken in conjunction with the accompanying drawings. It is noted that the drawings may not be to scale for clarity of illustration and will not detract from the understanding of the present application. In the drawings:

fig. 1 schematically illustrates a motorized breathing apparatus according to an embodiment of the present application;

fig. 2 is a perspective view schematically illustrating a filter cassette of a motorized breathing apparatus according to one example of the present application;

fig. 3 is a perspective view schematically illustrating a main body of a motorized breathing apparatus according to an example of the present application;

FIG. 4 schematically illustrates a host of a powered breathing apparatus according to one example of the present application, wherein the host will be connected to a joint of a connecting tube;

FIG. 5 schematically illustrates a combination of magnetic elements according to one example of the present application;

FIG. 6 schematically illustrates a control operation method according to one example of the present application.

Detailed Description

In the various figures of the present application, features that are structurally identical or functionally similar are denoted by the same reference numerals.

Fig. 1 schematically illustrates a motorized breathing apparatus 100 according to one embodiment of the present application. The electrical breathing apparatus 100 mainly includes an air filter device 200, a breathing mask 400, and a connection hose 300 connected between the air filter device 200 and the breathing mask 400. The air filter device 200 is worn by a user, for example, at the waist. The respiratory mask 400 is worn on the head by the user. For example, the respiratory mask 400 may be a medical epidemic isolation mask, a gas mask, a welding mask, or the like. The air filtration device 200 is driven by an internal electric fan (described below) to draw air from the environment, filtered and then provided to the respirator 400 via the connector hose 300 for inhalation by the user.

The air filter device 200 has a connection port 210 for detachably connecting with a nipple 310 of a connection hose 300. It should be clear to those skilled in the art that the shape of the connection port 210 is not limited to the form shown in fig. 1, but may be other shapes (as shown in fig. 3 and 4); similarly, the connector 310 may take any suitable shape as shown in fig. 1, 3 or 4, as long as the connection port 210 and the connector 310 can be removably connected as described below.

With further reference to fig. 2 and 3, according to an example of the present application, air filtration device 200 includes a host 220 and an air filtration cassette 230 that are removably attachable to one another. Host 220 includes a housing 2210. For example, the connection port 210 of the air filtration device 200 is located in the housing 2210. An interior space is defined in the housing 2210 to house an electric fan 2220 (only partially visible in fig. 2). In addition, an intake port 2230 is formed in the housing 2210. The housing 2210 is configured such that, in case the blower 2220 is powered on, gas can be sucked into the inner space where the blower 2220 is located through the suction port 2230 and discharged outside through the connection port 210. A rechargeable battery 240 is removably attached to the housing 2210 for powering the fan. A display screen 2214 for displaying various parameters and control buttons 2215 for controlling associated components in the host 220, such as the blower 2220, are included on the host 220.

Suction port 2230 is formed in an interface 2211 of housing 2210. A ring of flanges 2212 is disposed about the interface 2211. For example, the ring of flange 2212 may be integrally formed with housing 2210 or may also be formed of a resilient sealing material and then attached to a surface of housing 2210. Meanwhile, a plurality of latching portions, for example, three latching

portions

2213a, 2213b, 2213c are formed on the outer surface of the housing 2210 near the ring of the flange 2212, respectively.

The air-filter cassette 230 includes a housing 2310, which is generally square box shaped. It should be apparent to those skilled in the art that housing 2310 may also take other suitable shapes such as flat, etc. As further shown in fig. 3, housing 2310 of air-filter cassette 230 defines a space therein for receiving a filter media (not shown). The filter media may vary depending on the intended application of the powered breathing apparatus 100. A screen face 2311 is formed on the housing 2310. In contrast to the screen surface 2311, a suction surface (not shown in fig. 3) is formed on the housing 2310, and a plurality of openings are formed in the suction surface so that air can only pass through the suction surface, be filtered through the filter media, and then be discharged from the screen surface 2311.

A ring of flanges 2312 are also provided around the screening surface 2311. For example, the collar 2312 may be integrally formed with the housing 2310 or may also be formed of a resilient sealing material and then attached to a surface of the housing 2310. Further, a plurality of snaps, for example, three

snaps

2313a, 2313b, 2313c, are formed on the outer surface of the housing 2310, respectively, near the ring of the flange 2312. These

snaps

2313a, 2313b, 2313c of the air-filter cassette 230 are paired with those

snaps

2213a, 2213b, 2213c of the host computer 220 so that the air-filter cassette 230 can be snap-connected to the host computer 220 via a corresponding fit therebetween. When the air-filter cartridge 230 is properly connected (i.e., mounted in place) with the host 220, the interface 2211 of the filter face 2311 of the air-filter cartridge 230 and the host 220 face each other; and the flange 2312 of the air filter cassette 230 and the flange 2212 of the host 220 are in full contact with each other to form a sealed mating surface. This ensures that air filtered by the air filter cassette 230 is driven into the air inlet 2230 of the main unit 220 without coming into contact with the outside.

However, in the event that the air filter cassette 230 is not installed in place with the host 220, although the

snaps

2313a, 2313b, 2313c and the

snaps

2213a, 2213b, 2213c may engage with one another to connect the air filter cassette 230 with the host 220, it is possible that the flange 2312 of the air filter cassette 230 and the flange 2212 of the host 220 may not be in full contact with one another. Thus, a gap that may exist between flange 2312 and flange 2212 may cause harmful ambient air to be drawn into the host 220 and thus inhaled by the user.

Furthermore, as mentioned above, the filter media of the air filter cassette are different for different applications, which means that the fan of the host machine operates differently for air filter cassettes with different filter media, for example, the fan speed, the interval run time period, etc. In the prior art, this therefore required the user to manually reset the mode of operation of the main unit, and in particular of its fan, after changing a different air filter cassette. This firstly results in increased complexity for the user to use the powered breathing apparatus and secondly risks insufficient cleanliness of the air being inhaled if the user forgets to reset the main unit.

In view of the above, according to the solution of the present application, a plurality of proximity switches spaced apart from each other are arranged between the air filtration cassette 230 and the host 220, so that only when all of these proximity switches are correctly identified as the counterparts cooperating therewith, it is considered that the air filtration cassette 230 and the host 220 have been installed in place and that, according to the identification combination of the proximity switches, the type of the air filtration cassette 230 is automatically identified and accordingly the operating mode of the host 220, in particular the fan 2220 of the host, cooperating therewith is automatically reset.

In the embodiment of the present application, the proximity switch is preferably a hall sensor, and thus the following description will be given only by way of example of the hall sensor. However, it will be clear to a person skilled in the art that the proximity switch or similar devices that can be used in the solution of the present application can also be an electro-optical proximity switch, a vortex proximity switch, etc.

As shown in fig. 2 and 3, according to an embodiment of the present application, a plurality of hall sensors, for example, three

hall sensors

250a, 250b, 250c, are provided in a housing 2210 of the host 220. These hall sensors are electrically connected to a central processing unit (ECU) for controlling the main unit 220. For example, the

hall sensors

250a, 250b, 250c can be disposed in an interface 2211 of the housing 2210. Preferably, the

hall sensors

250a, 250b, 250c may be arranged hidden within the interface 2211, e.g. embedded within the housing 2210, such that the presence of these hall sensors is not visible from the outside. The air filter cartridge 230 is provided with a plurality of spaced registration positions at which a plurality of magnetic members may be selectively positioned as desired. For example, these alignment positions are in the plane of the screen face 2311 of the air-filter cartridge 230, so that they can be aligned with the respective plurality of hall sensors on the host 220 when the air-filter cartridge 230 is in place on the host 220. For example, three

registration positions

260a, 260b, 260c are provided on the air filter cassette 230.

Fig. 2 and 3 show the arrangement of the

hall sensors

250a, 250b, 250c and the

alignment positions

260a, 260b, 260c for illustrative purposes only, but it will be clear to those skilled in the art that the

hall sensors

250a, 250b, 250c may also be more dispersedly arranged in the host 220 in positions that can be respectively aligned with the air-filter cassette 230 when properly connected with the air-filter cassette 230, and that the

alignment positions

260a, 260b, 260c on the air-filter cassette 230 may also be rearranged accordingly.

First, the magnetic member is disposed at each of the three

alignment positions

260a, 260b, and 260c of the air filter cassette 230. For example, each magnetic member may be a member made of a permanent magnetic material such as a magnetic sheet or a magnetic bead. Preferably, the magnetic members may also be disposed in the housing 2310 of the air-filter cassette 230 in a concealed manner, for example, embedded in the housing 2310, so that the presence of the magnetic members is not visible from the outside. When the main machine 220 is energized, the ECU of the main machine 220 constantly monitors the states of the

hall sensors

250a, 250b, 250 c. Thus, when the air filter cartridge 230 and the host 220 are installed in place, the magnetic members at each

alignment position

260a, 260b, 260c are aligned in close proximity to each

hall sensor

250a, 250b, 250c, such that each

hall sensor

250a, 250b, 250c generates a trigger signal. When the ECU of the host 220 determines that all the

hall sensors

250a, 250b, and 250c generate the trigger signals, it is determined that the air filter cartridge 230 and the host 220 are installed in place, and a prompt device such as a display 2214, a buzzer (not shown), or a vibrator may be used to prompt the user; and/or only then can the user press the start key of the host 220 for further operation.

It should be clear to those skilled in the art that to ensure in-place mounting monitoring between the air-filtration cassette 230 and the host computer 220, only one such magnetic member may be provided on the air-filtration cassette 230 to cooperate with one hall sensor on the host computer 220. Of course, the accuracy of the in-place mounting monitoring can be further enhanced if two or more magnetic elements are disposed on the air-filter cartridge 230 and cooperate with corresponding two or more hall sensors on the host 220.

Alternatively and/or additionally, the following will describe how the host 220 according to the present application can automatically identify different models of air filtration cartridges, again taking as an example the selective arrangement of

hall sensors

250a, 250b, 250c and magnetic elements at

registration locations

260a, 260b, 260c on the air filtration cartridges 230.

Referring to fig. 5, it is assumed that three

hall sensors

250a, 250b, 250c are disposed on the host 220 exclusively for identifying the model of the air-filter cassette 230. In this application, different models of air filtration cassette mean that the filter media inside the air filtration cassette is arranged in different ways. There are three

registration positions

260a, 260b, 260c on the air filter cassette 230, but it is not necessary to provide a magnetic member at each registration position. In this way, different combinations of magnetic element layouts can be created on the air filter cassette 230. For example, it is shown in FIG. 5 that 2 can be generated on air filtration cassette 230³And 7 layout modes are defined as-1. If a hall sensor can generate a "1" trigger signal when it detects a magnetic member cooperating with the hall sensor, but can generate a "0" trigger signal when it cannot detect a magnetic member cooperating with the hall sensor, the combinations of the trigger signals generated by the three

hall sensors

250a, 250b, and 250c are "100", "010", "001", "110", "101", and "0", respectively11 "and" 111 ". The manufacturer of the air filtration cassette 230 can distinguish between different sizes of air filtration cassettes based on these combinations of trigger signals. For example, for a first type of air filtration cassette, the magnetic member is disposed only at the registration position 260 a; for the second type of air-filter cassette, the magnetic members are disposed only at the

registration positions

260a and 260 b; for the third type of air-filter cartridge, the magnetic members are disposed at all of the

registration positions

260a, 260b, 260c, so that when the

hall sensors

250a, 250b, 250c detect the trigger signal combinations "100", "110", and "111", respectively, it is possible to confirm the types of the air-filter cartridges as the first, second, and third types, respectively.

That is, for the purpose of determining the specification of the air-filtering cartridge, if N of the above-described hall sensors are present on the main unit 220 and N of the aligned positions in the air-filtering cartridge can selectively dispose the magnetic member (where N is an integer of 2 or more), 2 may be present on the air-filtering cartridge 230^N1 magnetic element in order to distinguish the type of air-filter cassette 230.

Referring to fig. 6, a method of controlling operation of the motorized breathing apparatus 100 according to one example of the present application is described below. It should be clear to those skilled in the art that this control method example may be stored as an execution code in a memory of the ECU so as to be read by the ECU and control the relevant components to execute.

According to the present application, a plurality of hall sensors are provided on the main unit 220, and a plurality of alignment positions are set on the air-filter cartridge 230 at locations where the air-filter cartridge 230 and the main unit 220 can be mounted in place, respectively, wherein the plurality of hall sensors may be divided into a first subset of hall sensors for determining whether the air-filter cartridge 230 is mounted in place with the main unit 220; and a second subset of hall sensors for determining the model of the air-filter cartridge 230. The first subset of hall sensors can include one or more hall sensors and the second subset of hall sensors can include N hall sensors, where N is an integer greater than or equal to 2. Thus, the plurality of aligned positions of the air-filter cartridge 230 are also divided into a first sub-group of aligned positions corresponding to the first sub-group of hall sensors, respectively; and a second subset of alignment positions corresponding to the second subset of hall sensors.

For air-filtration cassette 230, one magnetic member is disposed at each of the first subset of registration positions, while the magnetic members are selectively disposed at the second subset of registration positions in a manner similar to that shown in FIG. 5, depending on the model of air-filtration cassette 230. In addition, a library of operating modes corresponding to the specifications of the different air filtration cartridges (i.e., the arrangement of the magnetic elements at the second subset of aligned positions of the air filtration cartridges, such as the trigger signal combination of FIG. 5) is stored in advance on the memory of the host 220.

In step S10, the air-filter cartridge 230 is loaded onto the host computer 220. In step S20, it is determined whether the first set of hall sensors each monitor a corresponding magnetic member. If the corresponding magnetic members are not detected, it is determined that the air filter cartridge 230 is not installed in place on the host 220, and a prompt device such as a display 2214, a buzzer (not shown), or a vibrator may be provided to prompt the user to return to step S10 to reinstall the air filter cartridge 230. If all the first hall sensors monitor the corresponding magnetic members at step S20, go to step S30. In step S30, the layout of the corresponding magnetic elements monitored by the second group of hall sensors, i.e., the corresponding trigger signal combination, is determined. In step S40, it is queried according to the layout of the magnetic members determined in step S30 whether there is a layout corresponding to the previously stored library of operation patterns, and if so, the process goes to step S50, and if not, the process goes to step S60. At step S50, the host computer 220 automatically corrects the operating mode that matches the currently identified model of the air filter cartridge and allows the user to further control the operation of the host computer 220. At step S60, a prompt may be sent to the user via the display screen 2214, a buzzer (not shown), or a vibrator, etc., to prompt the user that the model of the current air filter cartridge is not recognized, and to prompt the user to replace the air filter cartridge or to prohibit the user from further controlling the operation of the host computer 220.

Similar to that shown above, a similar proximity switch design, such as a hall sensor and magnetic design, may also be employed between the fitting 310 of the connection hose 300 and the connection port 210 of the air filtration device 200. As shown in fig. 4, an engagement structure 210a is provided at the connection port 210, and a mating structure 310a for engaging with the engagement structure 210a is also provided on the joint 310. Meanwhile, one or more hall sensors 210b are disposed on the connection port 210 at or near the junction structure 210a, and correspondingly, one or more magnetic members are disposed on the connector 310 at or near the matching structure 310a (similar to fig. 2, the design can be hidden). These magnetic members are arranged to align with the hall sensor 210 of the connection port 210 when the connector 310 is properly installed in place with the connection port 210, thereby ensuring that the hall sensor 210b can generate a trigger signal accordingly. In a manner similar to that described with respect to fig. 6, it is determined whether the connector 310 is in place on the connection port 210 by monitoring the hall sensors 210b for the generation of a trigger signal with respect to the corresponding magnetic member.

Therefore, adopt the technical scheme of this application, not only can ensure that whether air filter box and host computer, coupling hose and air filter install in place, thereby the operation mode of the model resetting host computer that can also automatic identification air filter box has improved the use reliability and the convenience of the electronic breathing equipment of this application.

Although specific embodiments of the present application have been described herein in detail, they have been presented for purposes of illustration only and are not to be construed as limiting the scope of the application. Further, it should be clear to those skilled in the art that the various embodiments described in this specification can be used in combination with each other. Various substitutions, alterations, and modifications may be conceived without departing from the spirit and scope of the present application.

Claims

1. An air filtration device (200) for a powered breathing apparatus (100), comprising:

a host (220) comprising a housing (2210) within which is disposed an electric fan (2220); and

an air-filter cassette (230) removably connectable to the host (220), the housing (2210) of the host (220) comprising an interface surface (2211) facing the air-filter cassette (230) when the host (220) is connected to the air-filter cassette (230), the air-filter cassette (230) having a housing (2310), the housing (2310) of the air-filter cassette (230) comprising a filter screen surface (2311) facing the host (220) when the host (220) is connected to the air-filter cassette (230), characterized in that the housing (2210) of the host (220) further comprises a first set of hall sensors in the interface surface (2211), the first set of hall sensors comprising N hall sensors spaced from each other, where N is an integer greater than or equal to 2, the housing (2310) of the air-filter cassette (230) further comprising N alignment positions in the filter screen surface (2211), the N alignment positions are aligned with the N hall sensors respectively when the air-filter cartridge (230) is coupled to the housing (2210) of the host computer (220), the air-filter cartridge (230) including one or N magnetic members selectively disposed at the N alignment positions, the arrangement of the magnetic members at the N alignment positions corresponding to the manner in which the host computer (220) operates with respect to the air-filter cartridge (230).

2. The air filtration device (200) of claim 1 wherein said magnetic member has 2 in said N registration positions^N1 arrangement.

3. The air filtration device (200) of claim 1 or 2, wherein the hall sensor is provided hidden in a housing (2210) of the host machine (220); and/or the magnetic member is concealed within a housing (2310) of the air-filter cassette (230).

4. The air filtration device (200) of claim 1 or 2, wherein the housing (2210) of the host machine (220) further comprises a second set of hall sensors in the interface (2211), the second set of hall sensors comprising at least one hall sensor, and wherein the housing (2310) of the air filter cassette (230) further comprises at least one additional alignment position in the screen face (2310), the at least one additional alignment position respectively aligning the hall sensors of the second set of hall sensors when the air filter cassette (230) is mounted in position with the host machine (220), one additional magnet being provided at each of the at least one additional alignment positions, respectively.

5. The air filtration device (200) of claim 4, wherein the housing (2210) of the host machine (220) includes a ring of first flanges (2212) around the interface (2211), and the housing (2310) of the air filter cassette (230) includes a ring of second flanges (2312) around the screen face (2311), the first flanges (2212) fully contacting the second flanges (2312) when the air filter cassette (230) is installed in place with the host machine (220).

6. The air filtration device (200) of claim 5, wherein the first and/or second set of Hall sensors are located within an area surrounded by the first flange (2212), and/or wherein the N alignment positions and/or the at least one additional alignment position are located within an area surrounded by the second flange (2312).

7. An air filtration device (200) according to claim 5, further comprising a connection port (210) for detachable connection to a fitting (310) of a connection hose (300) of the motorized breathing apparatus (100), the connection port (210) being configured with a third set of Hall sensors comprising at least one Hall sensor, the fitting (310) comprising at least one additional alignment position, the at least one additional alignment position of the fitting (310) being aligned with the Hall sensors of the third set of Hall sensors respectively when the fitting (310) is in place with the connection port (210), one additional magnet being provided at each of the at least one additional alignment positions of the fitting (310) respectively.

8. The air filtration device (200) of claim 7, wherein the magnetic member comprises magnetic beads or magnetic flakes made of a permanent magnetic material.

9. An air filtration device for a powered breathing apparatus (100), comprising:

an air-filter cassette (230) removably connectable to said host (220), said housing (2210) of said host (220) comprising an interface surface (2211) facing said air-filter cassette (230) when said host (220) is connected to said air-filter cassette (230), said air-filter cassette (230) having a housing (2310), said housing (2310) of said air-filter cassette (230) comprising a filter screen surface (2311) facing said host (220) when said host (220) is connected to said air-filter cassette (230), characterized in that said housing (2210) of said host (220) further comprises a first set of proximity switches located in said interface surface (2211), said first set of proximity switches comprising N proximity switches spaced apart from each other, wherein N is an integer greater than or equal to 2, said housing (2310) of said air-filter cassette (230) further comprising N aligned positions located in said filter screen surface (2311), the N alignment positions are respectively aligned with the N proximity switches when the air-filter cassette (230) is coupled to the housing (2210) of the host computer (220), the air-filter cassette (230) including one or N counterparts capable of interacting with the proximity switches selectively disposed at the N alignment positions, the counterparts in the N alignment positions being arranged in a manner corresponding to an operation manner of the host computer (220) with respect to the air-filter cassette (230).

10. A powered breathing apparatus (100), comprising:

an air filtration device according to any one of claims 1 to 9;

a respiratory mask (400); and

a connection hose (300) connected between the breathing mask (400) and the air filtering device.

11. A method of operating an air filtration device (200) according to any one of claims 1 to 9 comprising:

connecting the air filtration cassette (230) to a host machine (220);

on the premise that N aligning positions of the air filter box (230) are respectively aligned with N Hall sensors of a first group of Hall sensors of the host (220), wherein N is an integer greater than or equal to 2, and the N Hall sensors are used for monitoring the condition that magnetic parts exist at the N aligning positions;

comparing the monitoring result with a magnetic member distribution stored in advance to determine the model of the air filter box (230);

altering the manner of operation of the host (220) based on the model of the air filtration cassette (230).

12. The method of claim 11, wherein after connecting the air-filter cartridge (230) to the host computer (220) and prior to determining the model of the air-filter cartridge (230), monitoring whether a second set of hall sensors of the host computer (220) are aligned with additional magnets of the air-filter cartridge (230) in additional alignment positions to determine whether the air-filter cartridge (230) is in place on the host computer (220).

13. The operating method according to claim 12, characterized in that if the air-filter cartridge (230) is not mounted in place on the host machine (220), an alarm is issued and/or the operation of the host machine (220) is stopped.